Release 4.14 kernel/trace/trace.c

/*
 * ring buffer based function tracer
 *
 * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com>
 * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
 *
 * Originally taken from the RT patch by:
 *    Arnaldo Carvalho de Melo <acme@redhat.com>
 *
 * Based on code from the latency_tracer, that is:
 *  Copyright (C) 2004-2006 Ingo Molnar
 *  Copyright (C) 2004 Nadia Yvette Chambers
 */
#include <linux/ring_buffer.h>
#include <generated/utsrelease.h>
#include <linux/stacktrace.h>
#include <linux/writeback.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
#include <linux/notifier.h>
#include <linux/irqflags.h>
#include <linux/debugfs.h>
#include <linux/tracefs.h>
#include <linux/pagemap.h>
#include <linux/hardirq.h>
#include <linux/linkage.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/ftrace.h>
#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/splice.h>
#include <linux/kdebug.h>
#include <linux/string.h>
#include <linux/mount.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/nmi.h>
#include <linux/fs.h>
#include <linux/trace.h>
#include <linux/sched/rt.h>

#include "trace.h"
#include "trace_output.h"

/*
 * On boot up, the ring buffer is set to the minimum size, so that
 * we do not waste memory on systems that are not using tracing.
 */

bool ring_buffer_expanded;

/*
 * We need to change this state when a selftest is running.
 * A selftest will lurk into the ring-buffer to count the
 * entries inserted during the selftest although some concurrent
 * insertions into the ring-buffer such as trace_printk could occurred
 * at the same time, giving false positive or negative results.
 */

static bool __read_mostly tracing_selftest_running;

/*
 * If a tracer is running, we do not want to run SELFTEST.
 */

bool __read_mostly tracing_selftest_disabled;

/* Pipe tracepoints to printk */

struct trace_iterator *tracepoint_print_iter;

int tracepoint_printk;
static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key);

/* For tracers that don't implement custom flags */

static struct tracer_opt dummy_tracer_opt[] = {
	{ }
};


static int

dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
{
	return 0;
}

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/*
 * To prevent the comm cache from being overwritten when no
 * tracing is active, only save the comm when a trace event
 * occurred.
 */
static DEFINE_PER_CPU(bool, trace_taskinfo_save);

/*
 * Kill all tracing for good (never come back).
 * It is initialized to 1 but will turn to zero if the initialization
 * of the tracer is successful. But that is the only place that sets
 * this back to zero.
 */

static int tracing_disabled = 1;


cpumask_var_t __read_mostly	tracing_buffer_mask;

/*
 * ftrace_dump_on_oops - variable to dump ftrace buffer on oops
 *
 * If there is an oops (or kernel panic) and the ftrace_dump_on_oops
 * is set, then ftrace_dump is called. This will output the contents
 * of the ftrace buffers to the console.  This is very useful for
 * capturing traces that lead to crashes and outputing it to a
 * serial console.
 *
 * It is default off, but you can enable it with either specifying
 * "ftrace_dump_on_oops" in the kernel command line, or setting
 * /proc/sys/kernel/ftrace_dump_on_oops
 * Set 1 if you want to dump buffers of all CPUs
 * Set 2 if you want to dump the buffer of the CPU that triggered oops
 */


enum ftrace_dump_mode ftrace_dump_on_oops;

/* When set, tracing will stop when a WARN*() is hit */

int __disable_trace_on_warning;

#ifdef CONFIG_TRACE_EVAL_MAP_FILE
/* Map of enums to their values, for "eval_map" file */

struct trace_eval_map_head {
	
struct module			*mod;
	
unsigned long			length;
};

union trace_eval_map_item;


struct trace_eval_map_tail {
	/*
         * "end" is first and points to NULL as it must be different
         * than "mod" or "eval_string"
         */
	
union trace_eval_map_item	*next;
	
const char			*end;	/* points to NULL */
};

static DEFINE_MUTEX(trace_eval_mutex);

/*
 * The trace_eval_maps are saved in an array with two extra elements,
 * one at the beginning, and one at the end. The beginning item contains
 * the count of the saved maps (head.length), and the module they
 * belong to if not built in (head.mod). The ending item contains a
 * pointer to the next array of saved eval_map items.
 */

union trace_eval_map_item {
	
struct trace_eval_map		map;
	
struct trace_eval_map_head	head;
	
struct trace_eval_map_tail	tail;
};


static union trace_eval_map_item *trace_eval_maps;
#endif /* CONFIG_TRACE_EVAL_MAP_FILE */

static int tracing_set_tracer(struct trace_array *tr, const char *buf);


#define MAX_TRACER_SIZE		100

static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;

static char *default_bootup_tracer;


static bool allocate_snapshot;



static int __init set_cmdline_ftrace(char *str)
{
	strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
	default_bootup_tracer = bootup_tracer_buf;
	/* We are using ftrace early, expand it */
	ring_buffer_expanded = true;
	return 1;
}
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__setup("ftrace=", set_cmdline_ftrace);



static int __init set_ftrace_dump_on_oops(char *str)
{
	if (*str++ != '=' || !*str) {
		ftrace_dump_on_oops = DUMP_ALL;
		return 1;
	}

	if (!strcmp("orig_cpu", str)) {
		ftrace_dump_on_oops = DUMP_ORIG;
                return 1;
        }

        return 0;
}
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__setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);



static int __init stop_trace_on_warning(char *str)
{
	if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0))
		__disable_trace_on_warning = 1;
	return 1;
}
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__setup("traceoff_on_warning", stop_trace_on_warning);



static int __init boot_alloc_snapshot(char *str)
{
	allocate_snapshot = true;
	/* We also need the main ring buffer expanded */
	ring_buffer_expanded = true;
	return 1;
}
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__setup("alloc_snapshot", boot_alloc_snapshot);



static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata;



static int __init set_trace_boot_options(char *str)
{
	strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
	return 0;
}
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__setup("trace_options=", set_trace_boot_options);


static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata;

static char *trace_boot_clock __initdata;



static int __init set_trace_boot_clock(char *str)
{
	strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE);
	trace_boot_clock = trace_boot_clock_buf;
	return 0;
}
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__setup("trace_clock=", set_trace_boot_clock);



static int __init set_tracepoint_printk(char *str)
{
	if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0))
		tracepoint_printk = 1;
	return 1;
}
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__setup("tp_printk", set_tracepoint_printk);



unsigned long long ns2usecs(u64 nsec)
{
	nsec += 500;
	do_div(nsec, 1000);
	return nsec;
}

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/* trace_flags holds trace_options default values */

#define TRACE_DEFAULT_FLAGS						\
	(FUNCTION_DEFAULT_FLAGS |                                       \
         TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |                  \
         TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO |                \
         TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE |                 \
         TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS)

/* trace_options that are only supported by global_trace */

#define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK |                    \
               TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD)

/* trace_flags that are default zero for instances */

#define ZEROED_TRACE_FLAGS \
	(TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK)

/*
 * The global_trace is the descriptor that holds the top-level tracing
 * buffers for the live tracing.
 */

static struct trace_array global_trace = {
	.trace_flags = TRACE_DEFAULT_FLAGS,
};


LIST_HEAD(ftrace_trace_arrays);



int trace_array_get(struct trace_array *this_tr)
{
	struct trace_array *tr;
	int ret = -ENODEV;

	mutex_lock(&trace_types_lock);
	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
		if (tr == this_tr) {
			tr->ref++;
			ret = 0;
			break;
		}
	}
	mutex_unlock(&trace_types_lock);

	return ret;
}

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static void __trace_array_put(struct trace_array *this_tr)
{
	WARN_ON(!this_tr->ref);
	this_tr->ref--;
}

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void trace_array_put(struct trace_array *this_tr)
{
	mutex_lock(&trace_types_lock);
	__trace_array_put(this_tr);
	mutex_unlock(&trace_types_lock);
}

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int call_filter_check_discard(struct trace_event_call *call, void *rec,
			      struct ring_buffer *buffer,
			      struct ring_buffer_event *event)
{
	if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
	    !filter_match_preds(call->filter, rec)) {
		__trace_event_discard_commit(buffer, event);
		return 1;
	}

	return 0;
}

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void trace_free_pid_list(struct trace_pid_list *pid_list)
{
	vfree(pid_list->pids);
	kfree(pid_list);
}

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/**
 * trace_find_filtered_pid - check if a pid exists in a filtered_pid list
 * @filtered_pids: The list of pids to check
 * @search_pid: The PID to find in @filtered_pids
 *
 * Returns true if @search_pid is fonud in @filtered_pids, and false otherwis.
 */

bool

trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid)
{
	/*
         * If pid_max changed after filtered_pids was created, we
         * by default ignore all pids greater than the previous pid_max.
         */
	if (search_pid >= filtered_pids->pid_max)
		return false;

	return test_bit(search_pid, filtered_pids->pids);
}

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/**
 * trace_ignore_this_task - should a task be ignored for tracing
 * @filtered_pids: The list of pids to check
 * @task: The task that should be ignored if not filtered
 *
 * Checks if @task should be traced or not from @filtered_pids.
 * Returns true if @task should *NOT* be traced.
 * Returns false if @task should be traced.
 */

bool

trace_ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct *task)
{
	/*
         * Return false, because if filtered_pids does not exist,
         * all pids are good to trace.
         */
	if (!filtered_pids)
		return false;

	return !trace_find_filtered_pid(filtered_pids, task->pid);
}

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/**
 * trace_pid_filter_add_remove - Add or remove a task from a pid_list
 * @pid_list: The list to modify
 * @self: The current task for fork or NULL for exit
 * @task: The task to add or remove
 *
 * If adding a task, if @self is defined, the task is only added if @self
 * is also included in @pid_list. This happens on fork and tasks should
 * only be added when the parent is listed. If @self is NULL, then the
 * @task pid will be removed from the list, which would happen on exit
 * of a task.
 */


void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
				  struct task_struct *self,
				  struct task_struct *task)
{
	if (!pid_list)
		return;

	/* For forks, we only add if the forking task is listed */
	if (self) {
		if (!trace_find_filtered_pid(pid_list, self->pid))
			return;
	}

	/* Sorry, but we don't support pid_max changing after setting */
	if (task->pid >= pid_list->pid_max)
		return;

	/* "self" is set for forks, and NULL for exits */
	if (self)
		set_bit(task->pid, pid_list->pids);
	else
		clear_bit(task->pid, pid_list->pids);
}

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/**
 * trace_pid_next - Used for seq_file to get to the next pid of a pid_list
 * @pid_list: The pid list to show
 * @v: The last pid that was shown (+1 the actual pid to let zero be displayed)
 * @pos: The position of the file
 *
 * This is used by the seq_file "next" operation to iterate the pids
 * listed in a trace_pid_list structure.
 *
 * Returns the pid+1 as we want to display pid of zero, but NULL would
 * stop the iteration.
 */


void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos)
{
	unsigned long pid = (unsigned long)v;

	(*pos)++;

	/* pid already is +1 of the actual prevous bit */
	pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid);

	/* Return pid + 1 to allow zero to be represented */
	if (pid < pid_list->pid_max)
		return (void *)(pid + 1);

	return NULL;
}

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/**
 * trace_pid_start - Used for seq_file to start reading pid lists
 * @pid_list: The pid list to show
 * @pos: The position of the file
 *
 * This is used by seq_file "start" operation to start the iteration
 * of listing pids.
 *
 * Returns the pid+1 as we want to display pid of zero, but NULL would
 * stop the iteration.
 */


void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos)
{
	unsigned long pid;
	loff_t l = 0;

	pid = find_first_bit(pid_list->pids, pid_list->pid_max);
	if (pid >= pid_list->pid_max)
		return NULL;

	/* Return pid + 1 so that zero can be the exit value */
	for (pid++; pid && l < *pos;
	     pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l))
		;
	return (void *)pid;
}

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/**
 * trace_pid_show - show the current pid in seq_file processing
 * @m: The seq_file structure to write into
 * @v: A void pointer of the pid (+1) value to display
 *
 * Can be directly used by seq_file operations to display the current
 * pid value.
 */


int trace_pid_show(struct seq_file *m, void *v)
{
	unsigned long pid = (unsigned long)v - 1;

	seq_printf(m, "%lu\n", pid);
	return 0;
}

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/* 128 should be much more than enough */

#define PID_BUF_SIZE		127



int trace_pid_write(struct trace_pid_list *filtered_pids,
		    struct trace_pid_list **new_pid_list,
		    const char __user *ubuf, size_t cnt)
{
	struct trace_pid_list *pid_list;
	struct trace_parser parser;
	unsigned long val;
	int nr_pids = 0;
	ssize_t read = 0;
	ssize_t ret = 0;
	loff_t pos;
	pid_t pid;

	if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1))
		return -ENOMEM;

	/*
         * Always recreate a new array. The write is an all or nothing
         * operation. Always create a new array when adding new pids by
         * the user. If the operation fails, then the current list is
         * not modified.
         */
	pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
	if (!pid_list)
		return -ENOMEM;

	pid_list->pid_max = READ_ONCE(pid_max);

	/* Only truncating will shrink pid_max */
	if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max)
		pid_list->pid_max = filtered_pids->pid_max;

	pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3);
	if (!pid_list->pids) {
		kfree(pid_list);
		return -ENOMEM;
	}

	if (filtered_pids) {
		/* copy the current bits to the new max */
		for_each_set_bit(pid, filtered_pids->pids,
				 filtered_pids->pid_max) {
			set_bit(pid, pid_list->pids);
			nr_pids++;
		}
	}

	while (cnt > 0) {

		pos = 0;

		ret = trace_get_user(&parser, ubuf, cnt, &pos);
		if (ret < 0 || !trace_parser_loaded(&parser))
			break;

		read += ret;
		ubuf += ret;
		cnt -= ret;

		parser.buffer[parser.idx] = 0;

		ret = -EINVAL;
		if (kstrtoul(parser.buffer, 0, &val))
			break;
		if (val >= pid_list->pid_max)
			break;

		pid = (pid_t)val;

		set_bit(pid, pid_list->pids);
		nr_pids++;

		trace_parser_clear(&parser);
		ret = 0;
	}
	trace_parser_put(&parser);

	if (ret < 0) {
		trace_free_pid_list(pid_list);
		return ret;
	}

	if (!nr_pids) {
		/* Cleared the list of pids */
		trace_free_pid_list(pid_list);
		read = ret;
		pid_list = NULL;
	}

	*new_pid_list = pid_list;

	return read;
}

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static u64 buffer_ftrace_now(struct trace_buffer *buf, int cpu)
{
	u64 ts;

	/* Early boot up does not have a buffer yet */
	if (!buf->buffer)
		return trace_clock_local();

	ts = ring_buffer_time_stamp(buf->buffer, cpu);
	ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts);

	return ts;
}

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u64 ftrace_now(int cpu)
{
	return buffer_ftrace_now(&global_trace.trace_buffer, cpu);
}

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/**
 * tracing_is_enabled - Show if global_trace has been disabled
 *
 * Shows if the global trace has been enabled or not. It uses the
 * mirror flag "buffer_disabled" to be used in fast paths such as for
 * the irqsoff tracer. But it may be inaccurate due to races. If you
 * need to know the accurate state, use tracing_is_on() which is a little
 * slower, but accurate.
 */


int tracing_is_enabled(void)
{
	/*
         * For quick access (irqsoff uses this in fast path), just
         * return the mirror variable of the state of the ring buffer.
         * It's a little racy, but we don't really care.
         */
	smp_rmb();
	return !global_trace.buffer_disabled;
}

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/*
 * trace_buf_size is the size in bytes that is allocated
 * for a buffer. Note, the number of bytes is always rounded
 * to page size.
 *
 * This number is purposely set to a low number of 16384.
 * If the dump on oops happens, it will be much appreciated
 * to not have to wait for all that output. Anyway this can be
 * boot time and run time configurable.
 */

#define TRACE_BUF_SIZE_DEFAULT	1441792UL 
/* 16384 * 88 (sizeof(entry)) */


static unsigned long		trace_buf_size = TRACE_BUF_SIZE_DEFAULT;

/* trace_types holds a link list of available tracers. */

static struct tracer		*trace_types __read_mostly;

/*
 * trace_types_lock is used to protect the trace_types list.
 */

DEFINE_MUTEX(trace_types_lock);

/*
 * serialize the access of the ring buffer
 *
 * ring buffer serializes readers, but it is low level protection.
 * The validity of the events (which returns by ring_buffer_peek() ..etc)
 * are not protected by ring buffer.
 *
 * The content of events may become garbage if we allow other process consumes
 * these events concurrently:
 *   A) the page of the consumed events may become a normal page
 *      (not reader page) in ring buffer, and this page will be rewrited
 *      by events producer.
 *   B) The page of the consumed events may become a page for splice_read,
 *      and this page will be returned to system.
 *
 * These primitives allow multi process access to different cpu ring buffer
 * concurrently.
 *
 * These primitives don't distinguish read-only and read-consume access.
 * Multi read-only access are also serialized.
 */

#ifdef CONFIG_SMP
static DECLARE_RWSEM(all_cpu_access_lock);
static DEFINE_PER_CPU(struct mutex, cpu_access_lock);



static inline void trace_access_lock(int cpu)
{
	if (cpu == RING_BUFFER_ALL_CPUS) {
		/* gain it for accessing the whole ring buffer. */
		down_write(&all_cpu_access_lock);
	} else {
		/* gain it for accessing a cpu ring buffer. */

		/* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */
		down_read(&all_cpu_access_lock);

		/* Secondly block other access to this @cpu ring buffer. */
		mutex_lock(&per_cpu(cpu_access_lock, cpu));
	}
}

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static inline void trace_access_unlock(int cpu)
{
	if (cpu == RING_BUFFER_ALL_CPUS) {
		up_write(&all_cpu_access_lock);
	} else {
		mutex_unlock(&per_cpu(cpu_access_lock, cpu));
		up_read(&all_cpu_access_lock);
	}
}

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static inline void trace_access_lock_init(void)
{
	int cpu;

	for_each_possible_cpu(cpu)
		mutex_init(&per_cpu(cpu_access_lock, cpu));
}

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#else

static DEFINE_MUTEX(access_lock);



static inline void trace_access_lock(int cpu)
{
	(void)cpu;
	mutex_lock(&access_lock);
}

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static inline void trace_access_unlock(int cpu)
{
	(void)cpu;
	mutex_unlock(&access_lock);
}

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static inline void trace_access_lock_init(void)
{
}

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#endif

#ifdef CONFIG_STACKTRACE
static void __ftrace_trace_stack(struct ring_buffer *buffer,
				 unsigned long flags,
				 int skip, int pc, struct pt_regs *regs);
static inline void ftrace_trace_stack(struct trace_array *tr,
				      struct ring_buffer *buffer,
				      unsigned long flags,
				      int skip, int pc, struct pt_regs *regs);

#else


static inline void __ftrace_trace_stack(struct ring_buffer *buffer,
					unsigned long flags,
					int skip, int pc, struct pt_regs *regs)
{
}
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static inline void ftrace_trace_stack(struct trace_array *tr,
				      struct ring_buffer *buffer,
				      unsigned long flags,
				      int skip, int pc, struct pt_regs *regs)
{
}

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#endif


static __always_inline void

trace_event_setup(struct ring_buffer_event *event,
		  int type, unsigned long flags, int pc)
{
	struct trace_entry *ent = ring_buffer_event_data(event);

	tracing_generic_entry_update(ent, flags, pc);
	ent->type = type;
}

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static __always_inline struct ring_buffer_event *

__trace_buffer_lock_reserve(struct ring_buffer *buffer,
			  int type,
			  unsigned long len,
			  unsigned long flags, int pc)
{
        struct ring_buffer_event *event;

	event = ring_buffer_lock_reserve(buffer, len);
	if (event != NULL)
		trace_event_setup(event, type, flags, pc);

	return event;
}

void 
tracer_tracing_on(struct trace_array *tr)
{
	if (tr->trace_buffer.buffer)
		ring_buffer_record_on(tr->trace_buffer.buffer);
	/*
         * This flag is looked at when buffers haven't been allocated
         * yet, or by some tracers (like irqsoff), that just want to
         * know if the ring buffer has been disabled, but it can handle
         * races of where it gets disabled but we still do a record.
         * As the check is in the fast path of the tracers, it is more
         * important to be fast than accurate.
         */
	tr->buffer_disabled = 0;
	/* Make the flag seen by readers */
	smp_wmb();
}

/**
 * tracing_on - enable tracing buffers
 *
 * This function enables tracing buffers that may have been
 * disabled with tracing_off.
 */


void tracing_on(void)
{
	tracer_tracing_on(&global_trace);
}
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EXPORT_SYMBOL_GPL(tracing_on);



static __always_inline void

__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event)
{
	__this_cpu_write(trace_taskinfo_save, true);

	/* If this is the temp buffer, we need to commit fully */
	if (this_cpu_read(trace_buffered_event) == event) {
		/* Length is in event->array[0] */
		ring_buffer_write(buffer, event->array[0], &event->array[1]);
		/* Release the temp buffer */
		this_cpu_dec(trace_buffered_event_cnt);
	} else
		ring_buffer_unlock_commit(buffer, event);
}

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/**
 * __trace_puts - write a constant string into the trace buffer.
 * @ip:    The address of the caller
 * @str:   The constant string to write
 * @size:  The size of the string.
 */


int __trace_puts(unsigned long ip, const char *str, int size)
{
	struct ring_buffer_event *event;
	struct ring_buffer *buffer;
	struct print_entry *entry;
	unsigned long irq_flags;
	int alloc;
	int pc;

	if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
		return 0;

	pc = preempt_count();

	if (unlikely(tracing_selftest_running || tracing_disabled))
		return 0;

	alloc = sizeof(*entry) + size + 2; /* possible \n added */

	local_save_flags(irq_flags);
	buffer = global_trace.trace_buffer.buffer;
	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, 
					    irq_flags, pc);
	if (!event)
		return 0;

	entry = ring_buffer_event_data(event);
	entry->ip = ip;

	memcpy(&entry->buf, str, size);

	/* Add a newline if necessary */
	if (entry->buf[size - 1] != '\n') {
		entry->buf[size] = '\n';
		entry->buf[size + 1] = '\0';
	} else
		entry->buf[size] = '\0';

	__buffer_unlock_commit(buffer, event);
	ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL);

	return size;
}
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84.93%
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EXPORT_SYMBOL_GPL(__trace_puts);

/**
 * __trace_bputs - write the pointer to a constant string into trace buffer
 * @ip:    The address of the caller
 * @str:   The constant string to write to the buffer to
 */


int __trace_bputs(unsigned long ip, const char *str)
{
	struct ring_buffer_event *event;
	struct ring_buffer *buffer;
	struct bputs_entry *entry;
	unsigned long irq_flags;
	int size = sizeof(struct bputs_entry);
	int pc;

	if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
		return 0;

	pc = preempt_count();

	if (unlikely(tracing_selftest_running || tracing_disabled))
		return 0;

	local_save_flags(irq_flags);
	buffer = global_trace.trace_buffer.buffer;
	event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size,
					    irq_flags, pc);
	if (!event)
		return 0;

	entry = ring_buffer_event_data(event);
	entry->ip			= ip;
	entry->str			= str;

	__buffer_unlock_commit(buffer, event);
	ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL);

	return 1;
}
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20.38%
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EXPORT_SYMBOL_GPL(__trace_bputs);

#ifdef CONFIG_TRACER_SNAPSHOT


static void tracing_snapshot_instance(struct trace_array *tr)
{
	struct tracer *tracer = tr->current_trace;
	unsigned long flags;

	if (in_nmi()) {
		internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n");
		internal_trace_puts("*** snapshot is being ignored        ***\n");
		return;
	}

	if (!tr->allocated_snapshot) {
		internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n");
		internal_trace_puts("*** stopping trace here!   ***\n");
		tracing_off();
		return;
	}

	/* Note, snapshot can not be used when the tracer uses it */
	if (tracer->use_max_tr) {
		internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n");
		internal_trace_puts("*** Can not use snapshot (sorry) ***\n");
		return;
	}

	local_irq_save(flags);
	update_max_tr(tr, current, smp_processor_id());
	local_irq_restore(flags);
}

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19
18.10%
1
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Zhao Lei
3
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/**
 * trace_snapshot - take a snapshot of the current buffer.
 *
 * This causes a swap between the snapshot buffer and the current live
 * tracing buffer. You can use this to take snapshots of the live
 * trace when some condition is triggered, but continue to trace.
 *
 * Note, make sure to allocate the snapshot with either
 * a tracing_snapshot_alloc(), or by doing it manually
 * with: echo 1 > /sys/kernel/debug/tracing/snapshot
 *
 * If the snapshot buffer is not allocated, it will stop tracing.
 * Basically making a permanent snapshot.
 */


void tracing_snapshot(void)
{
	struct trace_array *tr = &global_trace;

	tracing_snapshot_instance(tr);
}
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EXPORT_SYMBOL_GPL(tracing_snapshot);

static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf,
					struct trace_buffer *size_buf, int cpu_id);
static void set_buffer_entries(struct trace_buffer *buf, unsigned long val);



static int alloc_snapshot(struct trace_array *tr)
{
	int ret;

	if (!tr->allocated_snapshot) {

		/* allocate spare buffer */
		ret = resize_buffer_duplicate_size(&tr->max_buffer,
				   &tr->trace_buffer, RING_BUFFER_ALL_CPUS);
		if (ret < 0)
			return ret;

		tr->allocated_snapshot = true;
	}

	return 0;
}

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static void free_snapshot(struct trace_array *tr)
{
	/*
         * We don't free the ring buffer. instead, resize it because
         * The max_tr ring buffer has some state (e.g. ring->clock) and
         * we want preserve it.
         */
	ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS);
	set_buffer_entries(&tr->max_buffer, 1);
	tracing_reset_online_cpus(&tr->max_buffer);
	tr->allocated_snapshot = false;
}

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4
8.16%
1
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Fabian Frederick
1
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/**
 * tracing_alloc_snapshot - allocate snapshot buffer.
 *
 * This only allocates the snapshot buffer if it isn't already
 * allocated - it doesn't also take a snapshot.
 *
 * This is meant to be used in cases where the snapshot buffer needs
 * to be set up for events that can't sleep but need to be able to
 * trigger a snapshot.
 */


int tracing_alloc_snapshot(void)
{
	struct trace_array *tr = &global_trace;
	int ret;

	ret = alloc_snapshot(tr);
	WARN_ON(ret < 0);

	return ret;
}
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EXPORT_SYMBOL_GPL(tracing_alloc_snapshot);

/**
 * trace_snapshot_alloc - allocate and take a snapshot of the current buffer.
 *
 * This is similar to trace_snapshot(), but it will allocate the
 * snapshot buffer if it isn't already allocated. Use this only
 * where it is safe to sleep, as the allocation may sleep.
 *
 * This causes a swap between the snapshot buffer and the current live
 * tracing buffer. You can use this to take snapshots of the live
 * trace when some condition is triggered, but continue to trace.
 */


void tracing_snapshot_alloc(void)
{
	int ret;

	ret = tracing_alloc_snapshot();
	if (ret < 0)
		return;

	tracing_snapshot();
}
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EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
#else


void tracing_snapshot(void)
{
	WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used");
}
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EXPORT_SYMBOL_GPL(tracing_snapshot);


int tracing_alloc_snapshot(void)
{
	WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used");
	return -ENODEV;
}
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EXPORT_SYMBOL_GPL(tracing_alloc_snapshot);


void tracing_snapshot_alloc(void)
{
	/* Give warning */
	tracing_snapshot();
}
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EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
#endif /* CONFIG_TRACER_SNAPSHOT */



void tracer_tracing_off(struct trace_array *tr)
{
	if (tr->trace_buffer.buffer)
		ring_buffer_record_off(tr->trace_buffer.buffer);
	/*
         * This flag is looked at when buffers haven't been allocated
         * yet, or by some tracers (like irqsoff), that just want to
         * know if the ring buffer has been disabled, but it can handle
         * races of where it gets disabled but we still do a record.
         * As the check is in the fast path of the tracers, it is more
         * important to be fast than accurate.
         */
	tr->buffer_disabled = 1;
	/* Make the flag seen by readers */
	smp_wmb();
}

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/**
 * tracing_off - turn off tracing buffers
 *
 * This function stops the tracing buffers from recording data.
 * It does not disable any overhead the tracers themselves may
 * be causing. This function simply causes all recording to
 * the ring buffers to fail.
 */


void tracing_off(void)
{
	tracer_tracing_off(&global_trace);
}
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EXPORT_SYMBOL_GPL(tracing_off);



void disable_trace_on_warning(void)
{
	if (__disable_trace_on_warning)
		tracing_off();
}

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/**
 * tracer_tracing_is_on - show real state of ring buffer enabled
 * @tr : the trace array to know if ring buffer is enabled
 *
 * Shows real state of the ring buffer if it is enabled or not.
 */


int tracer_tracing_is_on(struct trace_array *tr)
{
	if (tr->trace_buffer.buffer)
		return ring_buffer_record_is_on(tr->trace_buffer.buffer);
	return !tr->buffer_disabled;
}

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/**
 * tracing_is_on - show state of ring buffers enabled
 */


int tracing_is_on(void)
{
	return tracer_tracing_is_on(&global_trace);
}
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EXPORT_SYMBOL_GPL(tracing_is_on);



static int __init set_buf_size(char *str)
{
	unsigned long buf_size;

	if (!str)
		return 0;
	buf_size = memparse(str, &str);
	/* nr_entries can not be zero */
	if (buf_size == 0)
		return 0;
	trace_buf_size = buf_size;
	return 1;
}
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__setup("trace_buf_size=", set_buf_size);



static int __init set_tracing_thresh(char *str)
{
	unsigned long threshold;
	int ret;

	if (!str)
		return 0;
	ret = kstrtoul(str, 0, &threshold);
	if (ret < 0)
		return 0;
	tracing_thresh = threshold * 1000;
	return 1;
}
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Eduard - Gabriel Munteanu
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37.50%
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Wang Tianhong
3
5.36%
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20.00%
Daniel Walter
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__setup("tracing_thresh=", set_tracing_thresh);



unsigned long nsecs_to_usecs(unsigned long nsecs)
{
	return nsecs / 1000;
}

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/*
 * TRACE_FLAGS is defined as a tuple matching bit masks with strings.
 * It uses C(a, b) where 'a' is the eval (enum) name and 'b' is the string that
 * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list
 * of strings in the order that the evals (enum) were defined.
 */

#undef C

#define C(a, b) b

/* These must match the bit postions in trace_iterator_flags */

static const char *trace_options[] = {
	TRACE_FLAGS
	NULL
};

static struct {
	
u64 (*func)(void);
	
const char *name;
	
int in_ns;		/* is this clock in nanoseconds? */

} trace_clocks[] = {
	{ trace_clock_local,		"local",	1 },
	{ trace_clock_global,		"global",	1 },
	{ trace_clock_counter,		"counter",	0 },
	{ trace_clock_jiffies,		"uptime",	0 },
	{ trace_clock,			"perf",		1 },
	{ ktime_get_mono_fast_ns,	"mono",		1 },
	{ ktime_get_raw_fast_ns,	"mono_raw",	1 },
	{ ktime_get_boot_fast_ns,	"boot",		1 },
	ARCH_TRACE_CLOCKS
};

/*
 * trace_parser_get_init - gets the buffer for trace parser
 */


int trace_parser_get_init(struct trace_parser *parser, int size)
{
	memset(parser, 0, sizeof(*parser));

	parser->buffer = kmalloc(size, GFP_KERNEL);
	if (!parser->buffer)
		return 1;

	parser->size = size;
	return 0;
}

Contributors
Person
Tokens
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Commits
CommitProp
Jiri Olsa
39
69.64%
1
33.33%
Steven Rostedt
17
30.36%
2
66.67%
Total
56
100.00%
3
100.00%

/*
 * trace_parser_put - frees the buffer for trace parser
 */


void trace_parser_put(struct trace_parser *parser)
{
	kfree(parser->buffer);
	parser->buffer = NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
9
39.13%
2
50.00%
Ingo Molnar
9
39.13%
1
25.00%
Jiri Olsa
5
21.74%
1
25.00%
Total
23
100.00%
4
100.00%

/*
 * trace_get_user - reads the user input string separated by  space
 * (matched by isspace(ch))
 *
 * For each string found the 'struct trace_parser' is updated,
 * and the function returns.
 *
 * Returns number of bytes read.
 *
 * See kernel/trace/trace.h for 'struct trace_parser' details.
 */


int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
	size_t cnt, loff_t *ppos)
{
	char ch;
	size_t read = 0;
	ssize_t ret;

	if (!*ppos)
		trace_parser_clear(parser);

	ret = get_user(ch, ubuf++);
	if (ret)
		goto out;

	read++;
	cnt--;

	/*
         * The parser is not finished with the last write,
         * continue reading the user input without skipping spaces.
         */
	if (!parser->cont) {
		/* skip white space */
		while (cnt && isspace(ch)) {
			ret = get_user(ch, ubuf++);
			if (ret)
				goto out;
			read++;
			cnt--;
		}

		/* only spaces were written */
		if (isspace(ch)) {
			*ppos += read;
			ret = read;
			goto out;
		}

		parser->idx = 0;
	}

	/* read the non-space input */
	while (cnt && !isspace(ch)) {
		if (parser->idx < parser->size - 1)
			parser->buffer[parser->idx++] = ch;
		else {
			ret = -EINVAL;
			goto out;
		}
		ret = get_user(ch, ubuf++);
		if (ret)
			goto out;
		read++;
		cnt--;
	}

	/* We either got finished input or we have to wait for another call. */
	if (isspace(ch)) {
		parser->buffer[parser->idx] = 0;
		parser->cont = false;
	} else if (parser->idx < parser->size - 1) {
		parser->cont = true;
		parser->buffer[parser->idx++] = ch;
	} else {
		ret = -EINVAL;
		goto out;
	}

	*ppos += read;
	ret = read;

out:
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jiri Olsa
213
71.72%
1
7.69%
Steven Rostedt
58
19.53%
7
53.85%
Ingo Molnar
16
5.39%
1
7.69%
Motohiro Kosaki
4
1.35%
1
7.69%
Harvey Harrison
4
1.35%
1
7.69%
Hiraku Toyooka
1
0.34%
1
7.69%
Li Zefan
1
0.34%
1
7.69%
Total
297
100.00%
13
100.00%

/* TODO add a seq_buf_to_buffer() */


static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
{
	int len;

	if (trace_seq_used(s) <= s->seq.readpos)
		return -EBUSY;

	len = trace_seq_used(s) - s->seq.readpos;
	if (cnt > len)
		cnt = len;
	memcpy(buf, s->buffer + s->seq.readpos, cnt);

	s->seq.readpos += cnt;
	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Eduard - Gabriel Munteanu
48
53.93%
1
7.14%
Steven Rostedt
29
32.58%
8
57.14%
Pekka Paalanen
7
7.87%
1
7.14%
Frédéric Weisbecker
2
2.25%
1
7.14%
Hiraku Toyooka
1
1.12%
1
7.14%
Vaibhav Nagarnaik
1
1.12%
1
7.14%
Dmitri Vorobiev
1
1.12%
1
7.14%
Total
89
100.00%
14
100.00%


unsigned long __read_mostly	tracing_thresh;

#ifdef CONFIG_TRACER_MAX_TRACE
/*
 * Copy the new maximum trace into the separate maximum-trace
 * structure. (this way the maximum trace is permanently saved,
 * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
 */

static void

__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
	struct trace_buffer *trace_buf = &tr->trace_buffer;
	struct trace_buffer *max_buf = &tr->max_buffer;
	struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu);
	struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu);

	max_buf->cpu = cpu;
	max_buf->time_start = data->preempt_timestamp;

	max_data->saved_latency = tr->max_latency;
	max_data->critical_start = data->critical_start;
	max_data->critical_end = data->critical_end;

	memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN);
	max_data->pid = tsk->pid;
	/*
         * If tsk == current, then use current_uid(), as that does not use
         * RCU. The irq tracer can be called out of RCU scope.
         */
	if (tsk == current)
		max_data->uid = current_uid();
	else
		max_data->uid = task_uid(tsk);

	max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
	max_data->policy = tsk->policy;
	max_data->rt_priority = tsk->rt_priority;

	/* record this tasks comm */
	tracing_record_cmdline(tsk);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
183
99.46%
7
87.50%
Arnaldo Carvalho de Melo
1
0.54%
1
12.50%
Total
184
100.00%
8
100.00%

/**
 * update_max_tr - snapshot all trace buffers from global_trace to max_tr
 * @tr: tracer
 * @tsk: the task with the latency
 * @cpu: The cpu that initiated the trace.
 *
 * Flip the buffers between the @tr and the max_tr and record information
 * about which task was the cause of this latency.
 */

void

update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
	struct ring_buffer *buf;

	if (tr->stop_count)
		return;

	WARN_ON_ONCE(!irqs_disabled());

	if (!tr->allocated_snapshot) {
		/* Only the nop tracer should hit this when disabling */
		WARN_ON_ONCE(tr->current_trace != &nop_trace);
		return;
	}

	arch_spin_lock(&tr->max_lock);

	buf = tr->trace_buffer.buffer;
	tr->trace_buffer.buffer = tr->max_buffer.buffer;
	tr->max_buffer.buffer = buf;

	__update_max_tr(tr, tsk, cpu);
	arch_spin_unlock(&tr->max_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
80
72.07%
10
58.82%
Hiraku Toyooka
12
10.81%
2
11.76%
Ingo Molnar
6
5.41%
1
5.88%
Motohiro Kosaki
5
4.50%
1
5.88%
Peter Zijlstra
4
3.60%
1
5.88%
Pekka J Enberg
2
1.80%
1
5.88%
Thomas Gleixner
2
1.80%
1
5.88%
Total
111
100.00%
17
100.00%

/**
 * update_max_tr_single - only copy one trace over, and reset the rest
 * @tr - tracer
 * @tsk - task with the latency
 * @cpu - the cpu of the buffer to copy.
 *
 * Flip the trace of a single CPU buffer between the @tr and the max_tr.
 */

void

update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
	int ret;

	if (tr->stop_count)
		return;

	WARN_ON_ONCE(!irqs_disabled());
	if (!tr->allocated_snapshot) {
		/* Only the nop tracer should hit this when disabling */
		WARN_ON_ONCE(tr->current_trace != &nop_trace);
		return;
	}

	arch_spin_lock(&tr->max_lock);

	ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu);

	if (ret == -EBUSY) {
		/*
                 * We failed to swap the buffer due to a commit taking
                 * place on this CPU. We fail to record, but we reset
                 * the max trace buffer (no one writes directly to it)
                 * and flag that it failed.
                 */
		trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_,
			"Failed to swap buffers due to commit in progress\n");
	}

	WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);

	__update_max_tr(tr, tsk, cpu);
	arch_spin_unlock(&tr->max_lock);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
101
73.19%
9
60.00%
Ingo Molnar
14
10.14%
1
6.67%
Linus Torvalds
12
8.70%
1
6.67%
Motohiro Kosaki
4
2.90%
1
6.67%
Harvey Harrison
3
2.17%
1
6.67%
Thomas Gleixner
2
1.45%
1
6.67%
Hiraku Toyooka
2
1.45%
1
6.67%
Total
138
100.00%
15
100.00%

#endif /* CONFIG_TRACER_MAX_TRACE */



static int wait_on_pipe(struct trace_iterator *iter, bool full)
{
	/* Iterators are static, they should be filled or empty */
	if (trace_buffer_iter(iter, iter->cpu_file))
		return 0;

	return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file,
				full);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
36
80.00%
8
72.73%
Rabin Vincent
5
11.11%
1
9.09%
Török Edwin
3
6.67%
1
9.09%
Ingo Molnar
1
2.22%
1
9.09%
Total
45
100.00%
11
100.00%

#ifdef CONFIG_FTRACE_STARTUP_TEST

static bool selftests_can_run;


struct trace_selftests {
	
struct list_head		list;
	
struct tracer			*type;
};

static LIST_HEAD(postponed_selftests);



static int save_selftest(struct tracer *type)
{
	struct trace_selftests *selftest;

	selftest = kmalloc(sizeof(*selftest), GFP_KERNEL);
	if (!selftest)
		return -ENOMEM;

	selftest->type = type;
	list_add(&selftest->list, &postponed_selftests);
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
58
100.00%
1
100.00%
Total
58
100.00%
1
100.00%



static int run_tracer_selftest(struct tracer *type)
{
	struct trace_array *tr = &global_trace;
	struct tracer *saved_tracer = tr->current_trace;
	int ret;

	if (!type->selftest || tracing_selftest_disabled)
		return 0;

	/*
         * If a tracer registers early in boot up (before scheduling is
         * initialized and such), then do not run its selftests yet.
         * Instead, run it a little later in the boot process.
         */
	if (!selftests_can_run)
		return save_selftest(type);

	/*
         * Run a selftest on this tracer.
         * Here we reset the trace buffer, and set the current
         * tracer to be this tracer. The tracer can then run some
         * internal tracing to verify that everything is in order.
         * If we fail, we do not register this tracer.
         */
	tracing_reset_online_cpus(&tr->trace_buffer);

	tr->current_trace = type;

#ifdef CONFIG_TRACER_MAX_TRACE
	if (type->use_max_tr) {
		/* If we expanded the buffers, make sure the max is expanded too */
		if (ring_buffer_expanded)
			ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size,
					   RING_BUFFER_ALL_CPUS);
		tr->allocated_snapshot = true;
	}
#endif

	/* the test is responsible for initializing and enabling */
	pr_info("Testing tracer %s: ", type->name);
	ret = type->selftest(type, tr);
	/* the test is responsible for resetting too */
	tr->current_trace = saved_tracer;
	if (ret) {
		printk(KERN_CONT "FAILED!\n");
		/* Add the warning after printing 'FAILED' */
		WARN_ON(1);
		return -1;
	}
	/* Only reset on passing, to avoid touching corrupted buffers */
	tracing_reset_online_cpus(&tr->trace_buffer);

#ifdef CONFIG_TRACER_MAX_TRACE
	if (type->use_max_tr) {
		tr->allocated_snapshot = false;

		/* Shrink the max buffer again */
		if (ring_buffer_expanded)
			ring_buffer_resize(tr->max_buffer.buffer, 1,
					   RING_BUFFER_ALL_CPUS);
	}
#endif

	printk(KERN_CONT "PASSED\n");
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
194
91.51%
10
76.92%
Ingo Molnar
13
6.13%
1
7.69%
Frédéric Weisbecker
3
1.42%
1
7.69%
Carsten Emde
2
0.94%
1
7.69%
Total
212
100.00%
13
100.00%



static __init int init_trace_selftests(void)
{
	struct trace_selftests *p, *n;
	struct tracer *t, **last;
	int ret;

	selftests_can_run = true;

	mutex_lock(&trace_types_lock);

	if (list_empty(&postponed_selftests))
		goto out;

	pr_info("Running postponed tracer tests:\n");

	list_for_each_entry_safe(p, n, &postponed_selftests, list) {
		ret = run_tracer_selftest(p->type);
		/* If the test fails, then warn and remove from available_tracers */
		if (ret < 0) {
			WARN(1, "tracer: %s failed selftest, disabling\n",
			     p->type->name);
			last = &trace_types;
			for (t = trace_types; t; t = t->next) {
				if (t == p->type) {
					*last = t->next;
					break;
				}
				last = &t->next;
			}
		}
		list_del(&p->list);
		kfree(p);
	}

 out:
	mutex_unlock(&trace_types_lock);

	return 0;
}
Contributors
Person
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CommitProp
Steven Rostedt
168
100.00%
1
100.00%
Total
168
100.00%
1
100.00%


core_initcall(init_trace_selftests);
#else


static inline int run_tracer_selftest(struct tracer *type)
{
	return 0;
}
Contributors
Person
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CommitProp
Steven Rostedt
15
100.00%
2
100.00%
Total
15
100.00%
2
100.00%

#endif /* CONFIG_FTRACE_STARTUP_TEST */

static void add_tracer_options(struct trace_array *tr, struct tracer *t);

static void __init apply_trace_boot_options(void);

/**
 * register_tracer - register a tracer with the ftrace system.
 * @type - the plugin for the tracer
 *
 * Register a new plugin tracer.
 */


int __init register_tracer(struct tracer *type)
{
	struct tracer *t;
	int ret = 0;

	if (!type->name) {
		pr_info("Tracer must have a name\n");
		return -1;
	}

	if (strlen(type->name) >= MAX_TRACER_SIZE) {
		pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
		return -1;
	}

	mutex_lock(&trace_types_lock);

	tracing_selftest_running = true;

	for (t = trace_types; t; t = t->next) {
		if (strcmp(type->name, t->name) == 0) {
			/* already found */
			pr_info("Tracer %s already registered\n",
				type->name);
			ret = -1;
			goto out;
		}
	}

	if (!type->set_flag)
		type->set_flag = &dummy_set_flag;
	if (!type->flags) {
		/*allocate a dummy tracer_flags*/
		type->flags = kmalloc(sizeof(*type->flags), GFP_KERNEL);
		if (!type->flags) {
			ret = -ENOMEM;
			goto out;
		}
		type->flags->val = 0;
		type->flags->opts = dummy_tracer_opt;
	} else
		if (!type->flags->opts)
			type->flags->opts = dummy_tracer_opt;

	/* store the tracer for __set_tracer_option */
	type->flags->trace = type;

	ret = run_tracer_selftest(type);
	if (ret < 0)
		goto out;

	type->next = trace_types;
	trace_types = type;
	add_tracer_options(&global_trace, type);

 out:
	tracing_selftest_running = false;
	mutex_unlock(&trace_types_lock);

	if (ret || !default_bootup_tracer)
		goto out_unlock;

	if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE))
		goto out_unlock;

	printk(KERN_INFO "Starting tracer '%s'\n", type->name);
	/* Do we want this tracer to start on bootup? */
	tracing_set_tracer(&global_trace, type->name);
	default_bootup_tracer = NULL;

	apply_trace_boot_options();

	/* disable other selftests, since this will break it. */
	tracing_selftest_disabled = true;
#ifdef CONFIG_FTRACE_STARTUP_TEST
	printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n",
	       type->name);
#endif

 out_unlock:
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
216
61.71%
12
46.15%
Chunyu Hu
56
16.00%
2
7.69%
Li Zefan
20
5.71%
1
3.85%
Török Edwin
14
4.00%
1
3.85%
Ingo Molnar
11
3.14%
2
7.69%
Pekka Paalanen
11
3.14%
1
3.85%
Frédéric Weisbecker
9
2.57%
1
3.85%
Thomas Gleixner
5
1.43%
2
7.69%
Jiaxing Wang
4
1.14%
1
3.85%
Heiko Carstens
2
0.57%
1
3.85%
Carsten Emde
1
0.29%
1
3.85%
Dan Carpenter
1
0.29%
1
3.85%
Total
350
100.00%
26
100.00%



void tracing_reset(struct trace_buffer *buf, int cpu)
{
	struct ring_buffer *buffer = buf->buffer;

	if (!buffer)
		return;

	ring_buffer_record_disable(buffer);

	/* Make sure all commits have finished */
	synchronize_sched();
	ring_buffer_reset_cpu(buffer, cpu);

	ring_buffer_record_enable(buffer);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
42
85.71%
9
81.82%
Ingo Molnar
6
12.24%
1
9.09%
Hiraku Toyooka
1
2.04%
1
9.09%
Total
49
100.00%
11
100.00%



void tracing_reset_online_cpus(struct trace_buffer *buf)
{
	struct ring_buffer *buffer = buf->buffer;
	int cpu;

	if (!buffer)
		return;

	ring_buffer_record_disable(buffer);

	/* Make sure all commits have finished */
	synchronize_sched();

	buf->time_start = buffer_ftrace_now(buf, buf->cpu);

	for_each_online_cpu(cpu)
		ring_buffer_reset_cpu(buffer, cpu);

	ring_buffer_record_enable(buffer);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
34
51.52%
7
50.00%
Ingo Molnar
10
15.15%
1
7.14%
Frédéric Weisbecker
8
12.12%
2
14.29%
Hiraku Toyooka
6
9.09%
1
7.14%
Pekka J Enberg
3
4.55%
1
7.14%
Alexander Z Lam
3
4.55%
1
7.14%
Peter Zijlstra
2
3.03%
1
7.14%
Total
66
100.00%
14
100.00%

/* Must have trace_types_lock held */


void tracing_reset_all_online_cpus(void)
{
	struct trace_array *tr;

	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
		if (!tr->clear_trace)
			continue;
		tr->clear_trace = false;
		tracing_reset_online_cpus(&tr->trace_buffer);
#ifdef CONFIG_TRACER_MAX_TRACE
		tracing_reset_online_cpus(&tr->max_buffer);
#endif
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
45
78.95%
4
80.00%
Arnaldo Carvalho de Melo
12
21.05%
1
20.00%
Total
57
100.00%
5
100.00%


static int *tgid_map;


#define SAVED_CMDLINES_DEFAULT 128

#define NO_CMDLINE_MAP UINT_MAX

static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED;

struct saved_cmdlines_buffer {
	
unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
	
unsigned *map_cmdline_to_pid;
	
unsigned cmdline_num;
	
int cmdline_idx;
	
char *saved_cmdlines;
};

static struct saved_cmdlines_buffer *savedcmd;

/* temporary disable recording */

static atomic_t trace_record_taskinfo_disabled __read_mostly;



static inline char *get_saved_cmdlines(int idx)
{
	return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN];
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
20
90.91%
1
33.33%
Steven Rostedt
2
9.09%
2
66.67%
Total
22
100.00%
3
100.00%



static inline void set_cmdline(int idx, const char *cmdline)
{
	memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
26
96.30%
1
50.00%
Steven Rostedt
1
3.70%
1
50.00%
Total
27
100.00%
2
100.00%



static int allocate_cmdlines_buffer(unsigned int val,
				    struct saved_cmdlines_buffer *s)
{
	s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid),
					GFP_KERNEL);
	if (!s->map_cmdline_to_pid)
		return -ENOMEM;

	s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL);
	if (!s->saved_cmdlines) {
		kfree(s->map_cmdline_to_pid);
		return -ENOMEM;
	}

	s->cmdline_idx = 0;
	s->cmdline_num = val;
	memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP,
	       sizeof(s->map_pid_to_cmdline));
	memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP,
	       val * sizeof(*s->map_cmdline_to_pid));

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
102
79.07%
1
14.29%
Steven Rostedt
24
18.60%
4
57.14%
Thomas Gleixner
2
1.55%
1
14.29%
Török Edwin
1
0.78%
1
14.29%
Total
129
100.00%
7
100.00%



static int trace_create_savedcmd(void)
{
	int ret;

	savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL);
	if (!savedcmd)
		return -ENOMEM;

	ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd);
	if (ret < 0) {
		kfree(savedcmd);
		savedcmd = NULL;
		return -ENOMEM;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
60
90.91%
1
20.00%
Steven Rostedt
4
6.06%
3
60.00%
Namhyung Kim
2
3.03%
1
20.00%
Total
66
100.00%
5
100.00%



int is_tracing_stopped(void)
{
	return global_trace.stop_count;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Carsten Emde
8
66.67%
1
33.33%
Steven Rostedt
3
25.00%
1
33.33%
Arnaldo Carvalho de Melo
1
8.33%
1
33.33%
Total
12
100.00%
3
100.00%

/**
 * tracing_start - quick start of the tracer
 *
 * If tracing is enabled but was stopped by tracing_stop,
 * this will start the tracer back up.
 */


void tracing_start(void)
{
	struct ring_buffer *buffer;
	unsigned long flags;

	if (tracing_disabled)
		return;

	raw_spin_lock_irqsave(&global_trace.start_lock, flags);
	if (--global_trace.stop_count) {
		if (global_trace.stop_count < 0) {
			/* Someone screwed up their debugging */
			WARN_ON_ONCE(1);
			global_trace.stop_count = 0;
		}
		goto out;
	}

	/* Prevent the buffers from switching */
	arch_spin_lock(&global_trace.max_lock);

	buffer = global_trace.trace_buffer.buffer;
	if (buffer)
		ring_buffer_record_enable(buffer);

#ifdef CONFIG_TRACER_MAX_TRACE
	buffer = global_trace.max_buffer.buffer;
	if (buffer)
		ring_buffer_record_enable(buffer);
#endif

	arch_spin_unlock(&global_trace.max_lock);

 out:
	raw_spin_unlock_irqrestore(&global_trace.start_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
105
78.95%
17
85.00%
Masami Hiramatsu
14
10.53%
1
5.00%
Frédéric Weisbecker
12
9.02%
1
5.00%
Thomas Gleixner
2
1.50%
1
5.00%
Total
133
100.00%
20
100.00%



static void tracing_start_tr(struct trace_array *tr)
{
	struct ring_buffer *buffer;
	unsigned long flags;

	if (tracing_disabled)
		return;

	/* If global, we need to also start the max tracer */
	if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
		return tracing_start();

	raw_spin_lock_irqsave(&tr->start_lock, flags);

	if (--tr->stop_count) {
		if (tr->stop_count < 0) {
			/* Someone screwed up their debugging */
			WARN_ON_ONCE(1);
			tr->stop_count = 0;
		}
		goto out;
	}

	buffer = tr->trace_buffer.buffer;
	if (buffer)
		ring_buffer_record_enable(buffer);

 out:
	raw_spin_unlock_irqrestore(&tr->start_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
82
73.87%
7
46.67%
Ingo Molnar
11
9.91%
4
26.67%
Frédéric Weisbecker
11
9.91%
1
6.67%
Tom Zanussi
4
3.60%
1
6.67%
Arnaldo Carvalho de Melo
2
1.80%
1
6.67%
Török Edwin
1
0.90%
1
6.67%
Total
111
100.00%
15
100.00%

/**
 * tracing_stop - quick stop of the tracer
 *
 * Light weight way to stop tracing. Use in conjunction with
 * tracing_start.
 */


void tracing_stop(void)
{
	struct ring_buffer *buffer;
	unsigned long flags;

	raw_spin_lock_irqsave(&global_trace.start_lock, flags);
	if (global_trace.stop_count++)
		goto out;

	/* Prevent the buffers from switching */
	arch_spin_lock(&global_trace.max_lock);

	buffer = global_trace.trace_buffer.buffer;
	if (buffer)
		ring_buffer_record_disable(buffer);

#ifdef CONFIG_TRACER_MAX_TRACE
	buffer = global_trace.max_buffer.buffer;
	if (buffer)
		ring_buffer_record_disable(buffer);
#endif

	arch_spin_unlock(&global_trace.max_lock);

 out:
	raw_spin_unlock_irqrestore(&global_trace.start_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
72
69.23%
7
50.00%
Ingo Molnar
19
18.27%
2
14.29%
Frédéric Weisbecker
10
9.62%
3
21.43%
Thomas Gleixner
2
1.92%
1
7.14%
Török Edwin
1
0.96%
1
7.14%
Total
104
100.00%
14
100.00%



static void tracing_stop_tr(struct trace_array *tr)
{
	struct ring_buffer *buffer;
	unsigned long flags;

	/* If global, we need to also stop the max tracer */
	if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
		return tracing_stop();

	raw_spin_lock_irqsave(&tr->start_lock, flags);
	if (tr->stop_count++)
		goto out;

	buffer = tr->trace_buffer.buffer;
	if (buffer)
		ring_buffer_record_disable(buffer);

 out:
	raw_spin_unlock_irqrestore(&tr->start_lock, flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
75
91.46%
9
81.82%
Ingo Molnar
6
7.32%
1
9.09%
Masami Hiramatsu
1
1.22%
1
9.09%
Total
82
100.00%
11
100.00%



static int trace_save_cmdline(struct task_struct *tsk)
{
	unsigned pid, idx;

	/* treat recording of idle task as a success */
	if (!tsk->pid)
		return 1;

	if (unlikely(tsk->pid > PID_MAX_DEFAULT))
		return 0;

	/*
         * It's not the end of the world if we don't get
         * the lock, but we also don't want to spin
         * nor do we want to disable interrupts,
         * so if we miss here, then better luck next time.
         */
	if (!arch_spin_trylock(&trace_cmdline_lock))
		return 0;

	idx = savedcmd->map_pid_to_cmdline[tsk->pid];
	if (idx == NO_CMDLINE_MAP) {
		idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num;

		/*
                 * Check whether the cmdline buffer at idx has a pid
                 * mapped. We are going to overwrite that entry so we
                 * need to clear the map_pid_to_cmdline. Otherwise we
                 * would read the new comm for the old pid.
                 */
		pid = savedcmd->map_cmdline_to_pid[idx];
		if (pid != NO_CMDLINE_MAP)
			savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP;

		savedcmd->map_cmdline_to_pid[idx] = tsk->pid;
		savedcmd->map_pid_to_cmdline[tsk->pid] = idx;

		savedcmd->cmdline_idx = idx;
	}

	set_cmdline(idx, tsk->comm);

	arch_spin_unlock(&trace_cmdline_lock);

	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
105
66.46%
9
45.00%
Yoshihiro Yunomae
18
11.39%
1
5.00%
Carsten Emde
12
7.59%
1
5.00%
Joel Fernandes
7
4.43%
1
5.00%
Thomas Gleixner
4
2.53%
2
10.00%
Masami Hiramatsu
4
2.53%
1
5.00%
Ingo Molnar
4
2.53%
1
5.00%
Tom Zanussi
2
1.27%
2
10.00%
Peter Zijlstra
1
0.63%
1
5.00%
Frédéric Weisbecker
1
0.63%
1
5.00%
Total
158
100.00%
20
100.00%



static void __trace_find_cmdline(int pid, char comm[])
{
	unsigned map;

	if (!pid) {
		strcpy(comm, "<idle>");
		return;
	}

	if (WARN_ON_ONCE(pid < 0)) {
		strcpy(comm, "<XXX>");
		return;
	}

	if (pid > PID_MAX_DEFAULT) {
		strcpy(comm, "<...>");
		return;
	}

	map = savedcmd->map_pid_to_cmdline[pid];
	if (map != NO_CMDLINE_MAP)
		strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN);
	else
		strcpy(comm, "<...>");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
58
57.43%
10
62.50%
Masami Hiramatsu
17
16.83%
1
6.25%
Frédéric Weisbecker
9
8.91%
1
6.25%
Thomas Gleixner
9
8.91%
2
12.50%
Yoshihiro Yunomae
5
4.95%
1
6.25%
Amey Telawane
3
2.97%
1
6.25%
Total
101
100.00%
16
100.00%



void trace_find_cmdline(int pid, char comm[])
{
	preempt_disable();
	arch_spin_lock(&trace_cmdline_lock);

	__trace_find_cmdline(pid, comm);

	arch_spin_unlock(&trace_cmdline_lock);
	preempt_enable();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
33
89.19%
4
66.67%
Heiko Carstens
3
8.11%
1
16.67%
Thomas Gleixner
1
2.70%
1
16.67%
Total
37
100.00%
6
100.00%



int trace_find_tgid(int pid)
{
	if (unlikely(!tgid_map || !pid || pid > PID_MAX_DEFAULT))
		return 0;

	return tgid_map[pid];
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
32
100.00%
1
100.00%
Total
32
100.00%
1
100.00%



static int trace_save_tgid(struct task_struct *tsk)
{
	/* treat recording of idle task as a success */
	if (!tsk->pid)
		return 1;

	if (unlikely(!tgid_map || tsk->pid > PID_MAX_DEFAULT))
		return 0;

	tgid_map[tsk->pid] = tsk->tgid;
	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
44
83.02%
2
40.00%
Steven Rostedt
7
13.21%
2
40.00%
Ingo Molnar
2
3.77%
1
20.00%
Total
53
100.00%
5
100.00%



static bool tracing_record_taskinfo_skip(int flags)
{
	if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID))))
		return true;
	if (atomic_read(&trace_record_taskinfo_disabled) || !tracing_is_on())
		return true;
	if (!__this_cpu_read(trace_taskinfo_save))
		return true;
	return false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
43
75.44%
1
16.67%
Steven Rostedt
12
21.05%
4
66.67%
Ingo Molnar
2
3.51%
1
16.67%
Total
57
100.00%
6
100.00%

/**
 * tracing_record_taskinfo - record the task info of a task
 *
 * @task  - task to record
 * @flags - TRACE_RECORD_CMDLINE for recording comm
 *        - TRACE_RECORD_TGID for recording tgid
 */


void tracing_record_taskinfo(struct task_struct *task, int flags)
{
	bool done;

	if (tracing_record_taskinfo_skip(flags))
		return;

	/*
         * Record as much task information as possible. If some fail, continue
         * to try to record the others.
         */
	done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task);
	done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task);

	/* If recording any information failed, retry again soon. */
	if (!done)
		return;

	__this_cpu_write(trace_taskinfo_save, false);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
62
92.54%
2
40.00%
Steven Rostedt
5
7.46%
3
60.00%
Total
67
100.00%
5
100.00%

/**
 * tracing_record_taskinfo_sched_switch - record task info for sched_switch
 *
 * @prev - previous task during sched_switch
 * @next - next task during sched_switch
 * @flags - TRACE_RECORD_CMDLINE for recording comm
 *          TRACE_RECORD_TGID for recording tgid
 */


void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
					  struct task_struct *next, int flags)
{
	bool done;

	if (tracing_record_taskinfo_skip(flags))
		return;

	/*
         * Record as much task information as possible. If some fail, continue
         * to try to record the others.
         */
	done  = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev);
	done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next);
	done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev);
	done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next);

	/* If recording any information failed, retry again soon. */
	if (!done)
		return;

	__this_cpu_write(trace_taskinfo_save, false);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
91
91.00%
2
28.57%
Steven Rostedt
7
7.00%
3
42.86%
Ingo Molnar
1
1.00%
1
14.29%
Masami Hiramatsu
1
1.00%
1
14.29%
Total
100
100.00%
7
100.00%

/* Helpers to record a specific task information */


void tracing_record_cmdline(struct task_struct *task)
{
	tracing_record_taskinfo(task, TRACE_RECORD_CMDLINE);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%



void tracing_record_tgid(struct task_struct *task)
{
	tracing_record_taskinfo(task, TRACE_RECORD_TGID);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
17
100.00%
1
100.00%
Total
17
100.00%
1
100.00%

/*
 * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq
 * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function
 * simplifies those functions and keeps them in sync.
 */


enum print_line_t trace_handle_return(struct trace_seq *s)
{
	return trace_seq_has_overflowed(s) ?
		TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
21
100.00%
1
100.00%
Total
21
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(trace_handle_return);


void

tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
			     int pc)
{
	struct task_struct *tsk = current;

	entry->preempt_count		= pc & 0xff;
	entry->pid			= (tsk) ? tsk->pid : 0;
	entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
		(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
#else
		TRACE_FLAG_IRQS_NOSUPPORT |
#endif
		((pc & NMI_MASK    ) ? TRACE_FLAG_NMI     : 0) |
		((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
		((pc & SOFTIRQ_OFFSET) ? TRACE_FLAG_SOFTIRQ : 0) |
		(tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
		(test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
91
73.39%
7
46.67%
Peter Zijlstra
22
17.74%
2
13.33%
Ingo Molnar
5
4.03%
2
13.33%
Al Viro
2
1.61%
1
6.67%
Tom Zanussi
2
1.61%
1
6.67%
Pavankumar Kondeti
1
0.81%
1
6.67%
Frédéric Weisbecker
1
0.81%
1
6.67%
Total
124
100.00%
15
100.00%


EXPORT_SYMBOL_GPL(tracing_generic_entry_update);


struct ring_buffer_event *

trace_buffer_lock_reserve(struct ring_buffer *buffer,
			  int type,
			  unsigned long len,
			  unsigned long flags, int pc)
{
	return __trace_buffer_lock_reserve(buffer, type, len, flags, pc);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Arnaldo Carvalho de Melo
23
57.50%
1
14.29%
Steven Rostedt
12
30.00%
3
42.86%
Tom Zanussi
4
10.00%
2
28.57%
Li Zefan
1
2.50%
1
14.29%
Total
40
100.00%
7
100.00%

DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
DEFINE_PER_CPU(int, trace_buffered_event_cnt);

static int trace_buffered_event_ref;

/**
 * trace_buffered_event_enable - enable buffering events
 *
 * When events are being filtered, it is quicker to use a temporary
 * buffer to write the event data into if there's a likely chance
 * that it will not be committed. The discard of the ring buffer
 * is not as fast as committing, and is much slower than copying
 * a commit.
 *
 * When an event is to be filtered, allocate per cpu buffers to
 * write the event data into, and if the event is filtered and discarded
 * it is simply dropped, otherwise, the entire data is to be committed
 * in one shot.
 */


void trace_buffered_event_enable(void)
{
	struct ring_buffer_event *event;
	struct page *page;
	int cpu;

	WARN_ON_ONCE(!mutex_is_locked(&event_mutex));

	if (trace_buffered_event_ref++)
		return;

	for_each_tracing_cpu(cpu) {
		page = alloc_pages_node(cpu_to_node(cpu),
					GFP_KERNEL | __GFP_NORETRY, 0);
		if (!page)
			goto failed;

		event = page_address(page);
		memset(event, 0, sizeof(*event));

		per_cpu(trace_buffered_event, cpu) = event;

		preempt_disable();
		if (cpu == smp_processor_id() &&
		    this_cpu_read(trace_buffered_event) !=
		    per_cpu(trace_buffered_event, cpu))
			WARN_ON_ONCE(1);
		preempt_enable();
	}

	return;
 failed:
	trace_buffered_event_disable();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
128
97.71%
3
75.00%
Arnaldo Carvalho de Melo
3
2.29%
1
25.00%
Total
131
100.00%
4
100.00%



static void enable_trace_buffered_event(void *data)
{
	/* Probably not needed, but do it anyway */
	smp_rmb();
	this_cpu_dec(trace_buffered_event_cnt);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
19
100.00%
2
100.00%
Total
19
100.00%
2
100.00%



static void disable_trace_buffered_event(void *data)
{
	this_cpu_inc(trace_buffered_event_cnt);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
15
100.00%
1
100.00%
Total
15
100.00%
1
100.00%

/**
 * trace_buffered_event_disable - disable buffering events
 *
 * When a filter is removed, it is faster to not use the buffered
 * events, and to commit directly into the ring buffer. Free up
 * the temp buffers when there are no more users. This requires
 * special synchronization with current events.
 */


void trace_buffered_event_disable(void)
{
	int cpu;

	WARN_ON_ONCE(!mutex_is_locked(&event_mutex));

	if (WARN_ON_ONCE(!trace_buffered_event_ref))
		return;

	if (--trace_buffered_event_ref)
		return;

	preempt_disable();
	/* For each CPU, set the buffer as used. */
	smp_call_function_many(tracing_buffer_mask,
			       disable_trace_buffered_event, NULL, 1);
	preempt_enable();

	/* Wait for all current users to finish */
	synchronize_sched();

	for_each_tracing_cpu(cpu) {
		free_page((unsigned long)per_cpu(trace_buffered_event, cpu));
		per_cpu(trace_buffered_event, cpu) = NULL;
	}
	/*
         * Make sure trace_buffered_event is NULL before clearing
         * trace_buffered_event_cnt.
         */
	smp_wmb();

	preempt_disable();
	/* Do the work on each cpu */
	smp_call_function_many(tracing_buffer_mask,
			       enable_trace_buffered_event, NULL, 1);
	preempt_enable();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
103
95.37%
3
75.00%
Arnaldo Carvalho de Melo
5
4.63%
1
25.00%
Total
108
100.00%
4
100.00%


static struct ring_buffer *temp_buffer;


struct ring_buffer_event *

trace_event_buffer_lock_reserve(struct ring_buffer **current_rb,
			  struct trace_event_file *trace_file,
			  int type, unsigned long len,
			  unsigned long flags, int pc)
{
	struct ring_buffer_event *entry;
	int val;

	*current_rb = trace_file->tr->trace_buffer.buffer;

	if ((trace_file->flags &
	     (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) &&
	    (entry = this_cpu_read(trace_buffered_event))) {
		/* Try to use the per cpu buffer first */
		val = this_cpu_inc_return(trace_buffered_event_cnt);
		if (val == 1) {
			trace_event_setup(entry, type, flags, pc);
			entry->array[0] = len;
			return entry;
		}
		this_cpu_dec(trace_buffered_event_cnt);
	}

	entry = __trace_buffer_lock_reserve(*current_rb,
					    type, len, flags, pc);
	/*
         * If tracing is off, but we have triggers enabled
         * we still need to look at the event data. Use the temp_buffer
         * to store the trace event for the tigger to use. It's recusive
         * safe and will not be recorded anywhere.
         */
	if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) {
		*current_rb = temp_buffer;
		entry = __trace_buffer_lock_reserve(*current_rb,
						    type, len, flags, pc);
	}
	return entry;
}
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Steven Rostedt
174
100.00%
9
100.00%
Total
174
100.00%
9
100.00%


EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve);

static DEFINE_SPINLOCK(tracepoint_iter_lock);
static DEFINE_MUTEX(tracepoint_printk_mutex);



static void output_printk(struct trace_event_buffer *fbuffer)
{
	struct trace_event_call *event_call;
	struct trace_event *event;
	unsigned long flags;
	struct trace_iterator *iter = tracepoint_print_iter;

	/* We should never get here if iter is NULL */
	if (WARN_ON_ONCE(!iter))
		return;

	event_call = fbuffer->trace_file->event_call;
	if (!event_call || !event_call->event.funcs ||
	    !event_call->event.funcs->trace)
		return;

	event = &fbuffer->trace_file->event_call->event;

	spin_lock_irqsave(&tracepoint_iter_lock, flags);
	trace_seq_init(&iter->seq);
	iter->ent = fbuffer->entry;
	event_call->event.funcs->trace(iter, 0, event);
	trace_seq_putc(&iter->seq, 0);
	printk("%s", iter->seq.buffer);

	spin_unlock_irqrestore(&tracepoint_iter_lock, flags);
}

Contributors
Person
Tokens
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Commits
CommitProp
Steven Rostedt
126
83.44%
5
83.33%
Masami Hiramatsu
25
16.56%
1
16.67%
Total
151
100.00%
6
100.00%



int tracepoint_printk_sysctl(struct ctl_table *table, int write,
			     void __user *buffer, size_t *lenp,
			     loff_t *ppos)
{
	int save_tracepoint_printk;
	int ret;

	mutex_lock(&tracepoint_printk_mutex);
	save_tracepoint_printk = tracepoint_printk;

	ret = proc_dointvec(table, write, buffer, lenp, ppos);

	/*
         * This will force exiting early, as tracepoint_printk
         * is always zero when tracepoint_printk_iter is not allocated
         */
	if (!tracepoint_print_iter)
		tracepoint_printk = 0;

	if (save_tracepoint_printk == tracepoint_printk)
		goto out;

	if (tracepoint_printk)
		static_key_enable(&tracepoint_printk_key.key);
	else
		static_key_disable(&tracepoint_printk_key.key);

 out:
	mutex_unlock(&tracepoint_printk_mutex);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
105
97.22%
2
50.00%
Frédéric Weisbecker
3
2.78%
2
50.00%
Total
108
100.00%
4
100.00%



void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
{
	if (static_key_false(&tracepoint_printk_key.key))
		output_printk(fbuffer);

	event_trigger_unlock_commit(fbuffer->trace_file, fbuffer->buffer,
				    fbuffer->event, fbuffer->entry,
				    fbuffer->flags, fbuffer->pc);
}
Contributors
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Steven Rostedt
52
100.00%
1
100.00%
Total
52
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(trace_event_buffer_commit);



void trace_buffer_unlock_commit_regs(struct trace_array *tr,
				     struct ring_buffer *buffer,
				     struct ring_buffer_event *event,
				     unsigned long flags, int pc,
				     struct pt_regs *regs)
{
	__buffer_unlock_commit(buffer, event);

	/*
         * If regs is not set, then skip the following callers:
         *   trace_buffer_unlock_commit_regs
         *   event_trigger_unlock_commit
         *   trace_event_buffer_commit
         *   trace_event_raw_event_sched_switch
         * Note, we can still get here via blktrace, wakeup tracer
         * and mmiotrace, but that's ok if they lose a function or
         * two. They are that meaningful.
         */
	ftrace_trace_stack(tr, buffer, flags, regs ? 0 : 4, pc, regs);
	ftrace_trace_userstack(buffer, flags, pc);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Masami Hiramatsu
44
64.71%
1
10.00%
Steven Rostedt
24
35.29%
9
90.00%
Total
68
100.00%
10
100.00%

/*
 * Similar to trace_buffer_unlock_commit_regs() but do not dump stack.
 */

void

trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
				   struct ring_buffer_event *event)
{
	__buffer_unlock_commit(buffer, event);
}

Contributors
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Steven Rostedt
22
100.00%
1
100.00%
Total
22
100.00%
1
100.00%


static void

trace_process_export(struct trace_export *export,
	       struct ring_buffer_event *event)
{
	struct trace_entry *entry;
	unsigned int size = 0;

	entry = ring_buffer_event_data(event);
	size = ring_buffer_event_length(event);
	export->write(entry, size);
}

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Chunyan Zhang
50
100.00%
1
100.00%
Total
50
100.00%
1
100.00%

static DEFINE_MUTEX(ftrace_export_lock);


static struct trace_export __rcu *ftrace_exports_list __read_mostly;

static DEFINE_STATIC_KEY_FALSE(ftrace_exports_enabled);



static inline void ftrace_exports_enable(void)
{
	static_branch_enable(&ftrace_exports_enabled);
}

Contributors
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Chunyan Zhang
15
100.00%
1
100.00%
Total
15
100.00%
1
100.00%



static inline void ftrace_exports_disable(void)
{
	static_branch_disable(&ftrace_exports_enabled);
}

Contributors
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Chunyan Zhang
15
100.00%
1
100.00%
Total
15
100.00%
1
100.00%



void ftrace_exports(struct ring_buffer_event *event)
{
	struct trace_export *export;

	preempt_disable_notrace();

	export = rcu_dereference_raw_notrace(ftrace_exports_list);
	while (export) {
		trace_process_export(export, event);
		export = rcu_dereference_raw_notrace(export->next);
	}

	preempt_enable_notrace();
}

Contributors
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Chunyan Zhang
50
100.00%
1
100.00%
Total
50
100.00%
1
100.00%


static inline void

add_trace_export(struct trace_export **list, struct trace_export *export)
{
	rcu_assign_pointer(export->next, *list);
	/*
         * We are entering export into the list but another
         * CPU might be walking that list. We need to make sure
         * the export->next pointer is valid before another CPU sees
         * the export pointer included into the list.
         */
	rcu_assign_pointer(*list, export);
}

Contributors
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Chunyan Zhang
37
100.00%
1
100.00%
Total
37
100.00%
1
100.00%


static inline int

rm_trace_export(struct trace_export **list, struct trace_export *export)
{
	struct trace_export **p;

	for (p = list; *p != NULL; p = &(*p)->next)
		if (*p == export)
			break;

	if (*p != export)
		return -1;

	rcu_assign_pointer(*p, (*p)->next);

	return 0;
}

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Chunyan Zhang
80
100.00%
1
100.00%
Total
80
100.00%
1
100.00%


static inline void

add_ftrace_export(struct trace_export **list, struct trace_export *export)
{
	if (*list == NULL)
		ftrace_exports_enable();

	add_trace_export(list, export);
}

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Chunyan Zhang
35
100.00%
1
100.00%
Total
35
100.00%
1
100.00%


static inline int

rm_ftrace_export(struct trace_export **list, struct trace_export *export)
{
	int ret;

	ret = rm_trace_export(list, export);
	if (*list == NULL)
		ftrace_exports_disable();

	return ret;
}

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Chunyan Zhang
43
100.00%
1
100.00%
Total
43
100.00%
1
100.00%



int register_ftrace_export(struct trace_export *export)
{
	if (WARN_ON_ONCE(!export->write))
		return -1;

	mutex_lock(&ftrace_export_lock);

	add_ftrace_export(&ftrace_exports_list, export);

	mutex_unlock(&ftrace_export_lock);

	return 0;
}
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Chunyan Zhang
47
100.00%
1
100.00%
Total
47
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(register_ftrace_export);



int unregister_ftrace_export(struct trace_export *export)
{
	int ret;

	mutex_lock(&ftrace_export_lock);

	ret = rm_ftrace_export(&ftrace_exports_list, export);

	mutex_unlock(&ftrace_export_lock);

	return ret;
}
Contributors
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Chunyan Zhang
38
100.00%
1
100.00%
Total
38
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(unregister_ftrace_export);


void

trace_function(struct trace_array *tr,
	       unsigned long ip, unsigned long parent_ip, unsigned long flags,
	       int pc)
{
	struct trace_event_call *call = &event_function;
	struct ring_buffer *buffer = tr->trace_buffer.buffer;
	struct ring_buffer_event *event;
	struct ftrace_entry *entry;

	event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
					    flags, pc);
	if (!event)
		return;
	entry	= ring_buffer_event_data(event);
	entry->ip			= ip;
	entry->parent_ip		= parent_ip;

	if (!call_filter_check_discard(call, entry, buffer, event)) {
		if (static_branch_unlikely(&ftrace_exports_enabled))
			ftrace_exports(event);
		__buffer_unlock_commit(buffer, event);
	}
}

Contributors
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Tokens
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CommitProp
Frédéric Weisbecker
59
44.03%
2
10.53%
Steven Rostedt
36
26.87%
10
52.63%
Tom Zanussi
19
14.18%
3
15.79%
Chunyan Zhang
15
11.19%
1
5.26%
Ingo Molnar
3
2.24%
1
5.26%
Arnaldo Carvalho de Melo
1
0.75%
1
5.26%
Török Edwin
1
0.75%
1
5.26%
Total
134
100.00%
19
100.00%

#ifdef CONFIG_STACKTRACE


#define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long))

struct ftrace_stack {
	
unsigned long		calls[FTRACE_STACK_MAX_ENTRIES];
};

static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack);
static DEFINE_PER_CPU(int, ftrace_stack_reserve);



static void __ftrace_trace_stack(struct ring_buffer *buffer,
				 unsigned long flags,
				 int skip, int pc, struct pt_regs *regs)
{
	struct trace_event_call *call = &event_kernel_stack;
	struct ring_buffer_event *event;
	struct stack_entry *entry;
	struct stack_trace trace;
	int use_stack;
	int size = FTRACE_STACK_ENTRIES;

	trace.nr_entries	= 0;
	trace.skip		= skip;

	/*
         * Add two, for this function and the call to save_stack_trace()
         * If regs is set, then these functions will not be in the way.
         */
	if (!regs)
		trace.skip += 2;

	/*
         * Since events can happen in NMIs there's no safe way to
         * use the per cpu ftrace_stacks. We reserve it and if an interrupt
         * or NMI comes in, it will just have to use the default
         * FTRACE_STACK_SIZE.
         */
	preempt_disable_notrace();

	use_stack = __this_cpu_inc_return(ftrace_stack_reserve);
	/*
         * We don't need any atomic variables, just a barrier.
         * If an interrupt comes in, we don't care, because it would
         * have exited and put the counter back to what we want.
         * We just need a barrier to keep gcc from moving things
         * around.
         */
	barrier();
	if (use_stack == 1) {
		trace.entries		= this_cpu_ptr(ftrace_stack.calls);
		trace.max_entries	= FTRACE_STACK_MAX_ENTRIES;

		if (regs)
			save_stack_trace_regs(regs, &trace);
		else
			save_stack_trace(&trace);

		if (trace.nr_entries > size)
			size = trace.nr_entries;
	} else
		/* From now on, use_stack is a boolean */
		use_stack = 0;

	size *= sizeof(unsigned long);

	event = __trace_buffer_lock_reserve(buffer, TRACE_STACK,
					    sizeof(*entry) + size, flags, pc);
	if (!event)
		goto out;
	entry = ring_buffer_event_data(event);

	memset(&entry->caller, 0, size);

	if (use_stack)
		memcpy(&entry->caller, trace.entries,
		       trace.nr_entries * sizeof(unsigned long));
	else {
		trace.max_entries	= FTRACE_STACK_ENTRIES;
		trace.entries		= entry->caller;
		if (regs)
			save_stack_trace_regs(regs, &trace);
		else
			save_stack_trace(&trace);
	}

	entry->size = trace.nr_entries;

	if (!call_filter_check_discard(call, entry, buffer, event))
		__buffer_unlock_commit(buffer, event);

 out:
	/* Again, don't let gcc optimize things here */
	barrier();
	__this_cpu_dec(ftrace_stack_reserve);
	preempt_enable_notrace();

}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
200
62.50%
15
55.56%
Frédéric Weisbecker
66
20.62%
1
3.70%
Tom Zanussi
22
6.88%
3
11.11%
Masami Hiramatsu
14
4.38%
1
3.70%
Ingo Molnar
8
2.50%
1
3.70%
Carsten Emde
3
0.94%
1
3.70%
Peter Zijlstra
2
0.62%
2
7.41%
Christoph Lameter
2
0.62%
1
3.70%
Shan Wei
2
0.62%
1
3.70%
Arnaldo Carvalho de Melo
1
0.31%
1
3.70%
Total
320
100.00%
27
100.00%



static inline void ftrace_trace_stack(struct trace_array *tr,
				      struct ring_buffer *buffer,
				      unsigned long flags,
				      int skip, int pc, struct pt_regs *regs)
{
	if (!(tr->trace_flags & TRACE_ITER_STACKTRACE))
		return;

	__ftrace_trace_stack(buffer, flags, skip, pc, regs);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
43
75.44%
5
83.33%
Frédéric Weisbecker
14
24.56%
1
16.67%
Total
57
100.00%
6
100.00%



void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
		   int pc)
{
	struct ring_buffer *buffer = tr->trace_buffer.buffer;

	if (rcu_is_watching()) {
		__ftrace_trace_stack(buffer, flags, skip, pc, NULL);
		return;
	}

	/*
         * When an NMI triggers, RCU is enabled via rcu_nmi_enter(),
         * but if the above rcu_is_watching() failed, then the NMI
         * triggered someplace critical, and rcu_irq_enter() should
         * not be called from NMI.
         */
	if (unlikely(in_nmi()))
		return;

	/*
         * It is possible that a function is being traced in a
         * location that RCU is not watching. A call to
         * rcu_irq_enter() will make sure that it is, but there's
         * a few internal rcu functions that could be traced
         * where that wont work either. In those cases, we just
         * do nothing.
         */
	if (unlikely(rcu_irq_enter_disabled()))
		return;

	rcu_irq_enter_irqson();
	__ftrace_trace_stack(buffer, flags, skip, pc, NULL);
	rcu_irq_exit_irqson();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
77
84.62%
10
83.33%
Frédéric Weisbecker
12
13.19%
1
8.33%
Masami Hiramatsu
2
2.20%
1
8.33%
Total
91
100.00%
12
100.00%

/**
 * trace_dump_stack - record a stack back trace in the trace buffer
 * @skip: Number of functions to skip (helper handlers)
 */


void trace_dump_stack(int skip)
{
	unsigned long flags;

	if (tracing_disabled || tracing_selftest_running)
		return;

	local_save_flags(flags);

	/*
         * Skip 3 more, seems to get us at the caller of
         * this function.
         */
	skip += 3;
	__ftrace_trace_stack(global_trace.trace_buffer.buffer,
			     flags, skip, preempt_count(), NULL);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
42
89.36%
5
62.50%
Frédéric Weisbecker
2
4.26%
1
12.50%
Masami Hiramatsu
2
4.26%
1
12.50%
Thomas Gleixner
1
2.13%
1
12.50%
Total
47
100.00%
8
100.00%

static DEFINE_PER_CPU(int, user_stack_count);


void

ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
{
	struct trace_event_call *call = &event_user_stack;
	struct ring_buffer_event *event;
	struct userstack_entry *entry;
	struct stack_trace trace;

	if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE))
		return;

	/*
         * NMIs can not handle page faults, even with fix ups.
         * The save user stack can (and often does) fault.
         */
	if (unlikely(in_nmi()))
		return;

	/*
         * prevent recursion, since the user stack tracing may
         * trigger other kernel events.
         */
	preempt_disable();
	if (__this_cpu_read(user_stack_count))
		goto out;

	__this_cpu_inc(user_stack_count);

	event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
					    sizeof(*entry), flags, pc);
	if (!event)
		goto out_drop_count;
	entry	= ring_buffer_event_data(event);

	entry->tgid		= current->tgid;
	memset(&entry->caller, 0, sizeof(entry->caller));

	trace.nr_entries	= 0;
	trace.max_entries	= FTRACE_STACK_ENTRIES;
	trace.skip		= 0;
	trace.entries		= entry->caller;

	save_stack_trace_user(&trace);
	if (!call_filter_check_discard(call, entry, buffer, event))
		__buffer_unlock_commit(buffer, event);

 out_drop_count:
	__this_cpu_dec(user_stack_count);
 out:
	preempt_enable();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
165
80.88%
16
66.67%
Tom Zanussi
14
6.86%
3
12.50%
Frédéric Weisbecker
11
5.39%
1
4.17%
Li Zefan
5
2.45%
1
4.17%
Arnaldo Carvalho de Melo
4
1.96%
1
4.17%
Ingo Molnar
4
1.96%
1
4.17%
Pekka Paalanen
1
0.49%
1
4.17%
Total
204
100.00%
24
100.00%

#ifdef UNUSED


static void __trace_userstack(struct trace_array *tr, unsigned long flags)
{
	ftrace_trace_userstack(tr, flags, preempt_count());
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
22
88.00%
5
71.43%
Ingo Molnar
2
8.00%
1
14.29%
Hannes Eder
1
4.00%
1
14.29%
Total
25
100.00%
7
100.00%

#endif /* UNUSED */

#endif /* CONFIG_STACKTRACE */

/* created for use with alloc_percpu */

struct trace_buffer_struct {
	
int nesting;
	
char buffer[4][TRACE_BUF_SIZE];
};


static struct trace_buffer_struct *trace_percpu_buffer;

/*
 * Thise allows for lockless recording.  If we're nested too deeply, then
 * this returns NULL.
 */


static char *get_trace_buf(void)
{
	struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer);

	if (!buffer || buffer->nesting >= 4)
		return NULL;

	buffer->nesting++;

	/* Interrupts must see nesting incremented before we use the buffer */
	barrier();
	return &buffer->buffer[buffer->nesting][0];
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
29
51.79%
6
66.67%
Andrew Lutomirski
19
33.93%
1
11.11%
Shan Wei
5
8.93%
1
11.11%
Török Edwin
3
5.36%
1
11.11%
Total
56
100.00%
9
100.00%



static void put_trace_buf(void)
{
	/* Don't let the decrement of nesting leak before this */
	barrier();
	this_cpu_dec(trace_percpu_buffer->nesting);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Lutomirski
15
78.95%
1
50.00%
Steven Rostedt
4
21.05%
1
50.00%
Total
19
100.00%
2
100.00%



static int alloc_percpu_trace_buffer(void)
{
	struct trace_buffer_struct *buffers;

	buffers = alloc_percpu(struct trace_buffer_struct);
	if (WARN(!buffers, "Could not allocate percpu trace_printk buffer"))
		return -ENOMEM;

	trace_percpu_buffer = buffers;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
34
80.95%
3
75.00%
Andrew Lutomirski
8
19.05%
1
25.00%
Total
42
100.00%
4
100.00%


static int buffers_allocated;



void trace_printk_init_buffers(void)
{
	if (buffers_allocated)
		return;

	if (alloc_percpu_trace_buffer())
		return;

	/* trace_printk() is for debug use only. Don't use it in production. */

	pr_warn("\n");
	pr_warn("**********************************************************\n");
	pr_warn("**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **\n");
	pr_warn("**                                                      **\n");
	pr_warn("** trace_printk() being used. Allocating extra memory.  **\n");
	pr_warn("**                                                      **\n");
	pr_warn("** This means that this is a DEBUG kernel and it is     **\n");
	pr_warn("** unsafe for production use.                           **\n");
	pr_warn("**                                                      **\n");
	pr_warn("** If you see this message and you are not debugging    **\n");
	pr_warn("** the kernel, report this immediately to your vendor!  **\n");
	pr_warn("**                                                      **\n");
	pr_warn("**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **\n");
	pr_warn("**********************************************************\n");

	/* Expand the buffers to set size */
	tracing_update_buffers();

	buffers_allocated = 1;

	/*
         * trace_printk_init_buffers() can be called by modules.
         * If that happens, then we need to start cmdline recording
         * directly here. If the global_trace.buffer is already
         * allocated here, then this was called by module code.
         */
	if (global_trace.trace_buffer.buffer)
		tracing_start_cmdline_record();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
80
73.39%
8
53.33%
Joe Perches
14
12.84%
1
6.67%
Borislav Petkov
5
4.59%
1
6.67%
Hiraku Toyooka
4
3.67%
1
6.67%
Frédéric Weisbecker
3
2.75%
1
6.67%
Török Edwin
1
0.92%
1
6.67%
Lai Jiangshan
1
0.92%
1
6.67%
Frans Klaver
1
0.92%
1
6.67%
Total
109
100.00%
15
100.00%



void trace_printk_start_comm(void)
{
	/* Start tracing comms if trace printk is set */
	if (!buffers_allocated)
		return;
	tracing_start_cmdline_record();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
14
82.35%
3
60.00%
Lai Jiangshan
2
11.76%
1
20.00%
Török Edwin
1
5.88%
1
20.00%
Total
17
100.00%
5
100.00%



static void trace_printk_start_stop_comm(int enabled)
{
	if (!buffers_allocated)
		return;

	if (enabled)
		tracing_start_cmdline_record();
	else
		tracing_stop_cmdline_record();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
16
61.54%
3
50.00%
Hiraku Toyooka
7
26.92%
1
16.67%
Lai Jiangshan
3
11.54%
2
33.33%
Total
26
100.00%
6
100.00%

/**
 * trace_vbprintk - write binary msg to tracing buffer
 *
 */


int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
{
	struct trace_event_call *call = &event_bprint;
	struct ring_buffer_event *event;
	struct ring_buffer *buffer;
	struct trace_array *tr = &global_trace;
	struct bprint_entry *entry;
	unsigned long flags;
	char *tbuffer;
	int len = 0, size, pc;

	if (unlikely(tracing_selftest_running || tracing_disabled))
		return 0;

	/* Don't pollute graph traces with trace_vprintk internals */
	pause_graph_tracing();

	pc = preempt_count();
	preempt_disable_notrace();

	tbuffer = get_trace_buf();
	if (!tbuffer) {
		len = 0;
		goto out_nobuffer;
	}

	len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args);

	if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0)
		goto out;

	local_save_flags(flags);
	size = sizeof(*entry) + sizeof(u32) * len;
	buffer = tr->trace_buffer.buffer;
	event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
					    flags, pc);
	if (!event)
		goto out;
	entry = ring_buffer_event_data(event);
	entry->ip			= ip;
	entry->fmt			= fmt;

	memcpy(entry->buf, tbuffer, sizeof(u32) * len);
	if (!call_filter_check_discard(call, entry, buffer, event)) {
		__buffer_unlock_commit(buffer, event);
		ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL);
	}

out:
	put_trace_buf();

out_nobuffer:
	preempt_enable_notrace();
	unpause_graph_tracing();

	return len;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
142
49.31%
16
72.73%
Frédéric Weisbecker
124
43.06%
2
9.09%
Tom Zanussi
16
5.56%
3
13.64%
Andrew Lutomirski
6
2.08%
1
4.55%
Total
288
100.00%
22
100.00%


EXPORT_SYMBOL_GPL(trace_vbprintk);


static int

__trace_array_vprintk(struct ring_buffer *buffer,
		      unsigned long ip, const char *fmt, va_list args)
{
	struct trace_event_call *call = &event_print;
	struct ring_buffer_event *event;
	int len = 0, size, pc;
	struct print_entry *entry;
	unsigned long flags;
	char *tbuffer;

	if (tracing_disabled || tracing_selftest_running)
		return 0;

	/* Don't pollute graph traces with trace_vprintk internals */
	pause_graph_tracing();

	pc = preempt_count();
	preempt_disable_notrace();


	tbuffer = get_trace_buf();
	if (!tbuffer) {
		len = 0;
		goto out_nobuffer;
	}

	len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);

	local_save_flags(flags);
	size = sizeof(*entry) + len + 1;
	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
					    flags, pc);
	if (!event)
		goto out;
	entry = ring_buffer_event_data(event);
	entry->ip = ip;

	memcpy(&entry->buf, tbuffer, len + 1);
	if (!call_filter_check_discard(call, entry, buffer, event)) {
		__buffer_unlock_commit(buffer, event);
		ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL);
	}

out:
	put_trace_buf();

out_nobuffer:
	preempt_enable_notrace();
	unpause_graph_tracing();

	return len;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
102
43.78%
18
62.07%
Frédéric Weisbecker
95
40.77%
1
3.45%
Tom Zanussi
12
5.15%
3
10.34%
Ingo Molnar
8
3.43%
2
6.90%
Andrew Lutomirski
6
2.58%
1
3.45%
Dan Carpenter
3
1.29%
1
3.45%
Carsten Emde
3
1.29%
1
3.45%
Török Edwin
2
0.86%
1
3.45%
Peter Zijlstra
2
0.86%
1
3.45%
Total
233
100.00%
29
100.00%



int trace_array_vprintk(struct trace_array *tr,
			unsigned long ip, const char *fmt, va_list args)
{
	return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
37
97.37%
5
83.33%
Török Edwin
1
2.63%
1
16.67%
Total
38
100.00%
6
100.00%



int trace_array_printk(struct trace_array *tr,
		       unsigned long ip, const char *fmt, ...)
{
	int ret;
	va_list ap;

	if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
		return 0;

	va_start(ap, fmt);
	ret = trace_array_vprintk(tr, ip, fmt, ap);
	va_end(ap);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
67
97.10%
7
87.50%
Pekka Paalanen
2
2.90%
1
12.50%
Total
69
100.00%
8
100.00%



int trace_array_printk_buf(struct ring_buffer *buffer,
			   unsigned long ip, const char *fmt, ...)
{
	int ret;
	va_list ap;

	if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
		return 0;

	va_start(ap, fmt);
	ret = __trace_array_vprintk(buffer, ip, fmt, ap);
	va_end(ap);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
69
100.00%
6
100.00%
Total
69
100.00%
6
100.00%



int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
{
	return trace_array_vprintk(&global_trace, ip, fmt, args);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
25
83.33%
3
42.86%
Ingo Molnar
3
10.00%
2
28.57%
Arnaldo Carvalho de Melo
1
3.33%
1
14.29%
Frédéric Weisbecker
1
3.33%
1
14.29%
Total
30
100.00%
7
100.00%


EXPORT_SYMBOL_GPL(trace_vprintk);



static void trace_iterator_increment(struct trace_iterator *iter)
{
	struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu);

	iter->idx++;
	if (buf_iter)
		ring_buffer_read(buf_iter, NULL);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Ingo Molnar
20
48.78%
2
22.22%
Steven Rostedt
11
26.83%
4
44.44%
Frédéric Weisbecker
8
19.51%
1
11.11%
Peter Zijlstra
2
4.88%
2
22.22%
Total
41
100.00%
9
100.00%


static struct trace_entry *

peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts,
		unsigned long *lost_events)
{
	struct ring_buffer_event *event;
	struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu);

	if (buf_iter)
		event = ring_buffer_iter_peek(buf_iter, ts);
	else
		event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts,
					 lost_events);

	if (event) {
		iter->ent_size = ring_buffer_event_length(event);
		return ring_buffer_event_data(event);
	}
	iter->ent_size = 0;
	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
50
48.54%
10
71.43%
Frédéric Weisbecker
38
36.89%
2
14.29%
Ingo Molnar
13
12.62%
1
7.14%
Arnaldo Carvalho de Melo
2
1.94%
1
7.14%
Total
103
100.00%
14
100.00%


static struct trace_entry *

__find_next_entry(struct trace_iterator *iter, int *ent_cpu,
		  unsigned long *missing_events, u64 *ent_ts)
{
	struct ring_buffer *buffer = iter->trace_buffer->buffer;
	struct trace_entry *ent, *next = NULL;
	unsigned long lost_events = 0, next_lost = 0;
	int cpu_file = iter->cpu_file;
	u64 next_ts = 0, ts;
	int next_cpu = -1;
	int next_size = 0;
	int cpu;

	/*
         * If we are in a per_cpu trace file, don't bother by iterating over
         * all cpu and peek directly.
         */
	if (cpu_file > RING_BUFFER_ALL_CPUS) {
		if (ring_buffer_empty_cpu(buffer, cpu_file))
			return NULL;
		ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events);
		if (ent_cpu)
			*ent_cpu = cpu_file;

		return ent;
	}

	for_each_tracing_cpu(cpu) {

		if (ring_buffer_empty_cpu(buffer, cpu))
			continue;

		ent = peek_next_entry(iter, cpu, &ts, &lost_events);

		/*
                 * Pick the entry with the smallest timestamp:
                 */
		if (ent && (!next || ts < next_ts)) {
			next = ent;
			next_cpu = cpu;
			next_ts = ts;
			next_lost = lost_events;
			next_size = iter->ent_size;
		}
	}

	iter->ent_size = next_size;

	if (ent_cpu)
		*ent_cpu = next_cpu;

	if (ent_ts)
		*ent_ts = next_ts;

	if (missing_events)
		*missing_events = next_lost;

	return next;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
181
76.69%
14
77.78%
Frédéric Weisbecker
30
12.71%
1
5.56%
Ingo Molnar
17
7.20%
1
5.56%
Pekka Paalanen
6
2.54%
1
5.56%
Lai Jiangshan
2
0.85%
1
5.56%
Total
236
100.00%
18
100.00%

/* Find the next real entry, without updating the iterator itself */


struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
					  int *ent_cpu, u64 *ent_ts)
{
	return __find_next_entry(iter, ent_cpu, NULL, ent_ts);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
31
96.88%
4
80.00%
Frédéric Weisbecker
1
3.12%
1
20.00%
Total
32
100.00%
5
100.00%

/* Find the next real entry, and increment the iterator to the next entry */


void *trace_find_next_entry_inc(struct trace_iterator *iter)
{
	iter->ent = __find_next_entry(iter, &iter->cpu,
				      &iter->lost_events, &iter->ts);

	if (iter->ent)
		trace_iterator_increment(iter);

	return iter->ent ? iter : NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
34
61.82%
4
40.00%
Frédéric Weisbecker
7
12.73%
3
30.00%
Ingo Molnar
7
12.73%
1
10.00%
Thomas Gleixner
6
10.91%
1
10.00%
Jason Wessel
1
1.82%
1
10.00%
Total
55
100.00%
10
100.00%



static void trace_consume(struct trace_iterator *iter)
{
	ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts,
			    &iter->lost_events);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
25
73.53%
6
60.00%
Frédéric Weisbecker
5
14.71%
2
20.00%
Ingo Molnar
4
11.76%
2
20.00%
Total
34
100.00%
10
100.00%



static void *s_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct trace_iterator *iter = m->private;
	int i = (int)*pos;
	void *ent;

	WARN_ON_ONCE(iter->leftover);

	(*pos)++;

	/* can't go backwards */
	if (iter->idx > i)
		return NULL;

	if (iter->idx < 0)
		ent = trace_find_next_entry_inc(iter);
	else
		ent = iter;

	while (ent && iter->idx < i)
		ent = trace_find_next_entry_inc(iter);

	iter->pos = *pos;

	return ent;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
62
54.39%
5
45.45%
Jiri Olsa
36
31.58%
1
9.09%
Török Edwin
13
11.40%
3
27.27%
Jason Wessel
2
1.75%
1
9.09%
Pekka Paalanen
1
0.88%
1
9.09%
Total
114
100.00%
11
100.00%



void tracing_iter_reset(struct trace_iterator *iter, int cpu)
{
	struct ring_buffer_event *event;
	struct ring_buffer_iter *buf_iter;
	unsigned long entries = 0;
	u64 ts;

	per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0;

	buf_iter = trace_buffer_iter(iter, cpu);
	if (!buf_iter)
		return;

	ring_buffer_iter_reset(buf_iter);

	/*
         * We could have the case with the max latency tracers
         * that a reset never took place on a cpu. This is evident
         * by the timestamp being before the start of the buffer.
         */
	while ((event = ring_buffer_iter_peek(buf_iter, &ts))) {
		if (ts >= iter->trace_buffer->time_start)
			break;
		entries++;
		ring_buffer_read(buf_iter, NULL);
	}

	per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
87
72.50%
6
85.71%
Jiri Olsa
33
27.50%
1
14.29%
Total
120
100.00%
7
100.00%

/*
 * The current tracer is copied to avoid a global locking
 * all around.
 */


static void *s_start(struct seq_file *m, loff_t *pos)
{
	struct trace_iterator *iter = m->private;
	struct trace_array *tr = iter->tr;
	int cpu_file = iter->cpu_file;
	void *p = NULL;
	loff_t l = 0;
	int cpu;

	/*
         * copy the tracer to avoid using a global lock all around.
         * iter->trace is a copy of current_trace, the pointer to the
         * name may be used instead of a strcmp(), as iter->trace->name
         * will point to the same string as current_trace->name.
         */
	mutex_lock(&trace_types_lock);
	if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name))
		*iter->trace = *tr->current_trace;
	mutex_unlock(&trace_types_lock);

#ifdef CONFIG_TRACER_MAX_TRACE
	if (iter->snapshot && iter->trace->use_max_tr)
		return ERR_PTR(-EBUSY);
#endif

	if (!iter->snapshot)
		atomic_inc(&trace_record_taskinfo_disabled);

	if (*pos != iter->pos) {
		iter->ent = NULL;
		iter->cpu = 0;
		iter->idx = -1;

		if (cpu_file == RING_BUFFER_ALL_CPUS) {
			for_each_tracing_cpu(cpu)
				tracing_iter_reset(iter, cpu);
		} else
			tracing_iter_reset(iter, cpu_file);

		iter->leftover = 0;
		for (p = iter; p && l < *pos; p = s_next(m, p, &l))
			;

	} else {
		/*
                 * If we overflowed the seq_file before, then we want
                 * to just reuse the trace_seq buffer again.
                 */
		if (iter->leftover)
			p = iter;
		else {
			l = *pos - 1;
			p = s_next(m, p, &l);
		}
	}

	trace_event_read_lock();
	trace_access_lock(cpu_file);
	return p;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
194
71.32%
13
54.17%
Hiraku Toyooka
26
9.56%
2
8.33%
Frédéric Weisbecker
23
8.46%
2
8.33%
Török Edwin
14
5.15%
2
8.33%
Lai Jiangshan
12
4.41%
3
12.50%
Ingo Molnar
2
0.74%
1
4.17%
Joel Fernandes
1
0.37%
1
4.17%
Total
272
100.00%
24
100.00%



static void s_stop(struct seq_file *m, void *p)
{
	struct trace_iterator *iter = m->private;

#ifdef CONFIG_TRACER_MAX_TRACE
	if (iter->snapshot && iter->trace->use_max_tr)
		return;
#endif

	if (!iter->snapshot)
		atomic_dec(&trace_record_taskinfo_disabled);

	trace_access_unlock(iter->cpu_file);
	trace_event_read_unlock();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
45
69.23%
6
60.00%
Hiraku Toyooka
10
15.38%
1
10.00%
Lai Jiangshan
9
13.85%
2
20.00%
Joel Fernandes
1
1.54%
1
10.00%
Total
65
100.00%
10
100.00%


static void

get_total_entries(struct trace_buffer *buf,
		  unsigned long *total, unsigned long *entries)
{
	unsigned long count;
	int cpu;

	*total = 0;
	*entries = 0;

	for_each_tracing_cpu(cpu) {
		count = ring_buffer_entries_cpu(buf->buffer, cpu);
		/*
                 * If this buffer has skipped entries, then we hold all
                 * entries for the trace and we need to ignore the
                 * ones before the time stamp.
                 */
		if (per_cpu_ptr(buf->data, cpu)->skipped_entries) {
			count -= per_cpu_ptr(buf->data, cpu)->skipped_entries;
			/* total is the same as the entries */
			*total += count;
		} else
			*total += count +
				ring_buffer_overrun_cpu(buf->buffer, cpu);
		*entries += count;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
104
94.55%
6
85.71%
Markus Metzger
6
5.45%
1
14.29%
Total
110
100.00%
7
100.00%



static void print_lat_help_header(struct seq_file *m)
{
	seq_puts(m, "#                  _------=> CPU#            \n"
		    "#                 / _-----=> irqs-off        \n"
		    "#                | / _----=> need-resched    \n"
		    "#                || / _---=> hardirq/softirq \n"
		    "#                ||| / _--=> preempt-depth   \n"
		    "#                |||| /     delay            \n"
		    "#  cmd     pid   ||||| time  |   caller      \n"
		    "#     \\   /      |||||  \\    |   /         \n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
17
68.00%
3
50.00%
Michael Ellerman
5
20.00%
1
16.67%
Rasmus Villemoes
2
8.00%
1
16.67%
Ingo Molnar
1
4.00%
1
16.67%
Total
25
100.00%
6
100.00%



static void print_event_info(struct trace_buffer *buf, struct seq_file *m)
{
	unsigned long total;
	unsigned long entries;

	get_total_entries(buf, &total, &entries);
	seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu   #P:%d\n",
		   entries, total, num_online_cpus());
	seq_puts(m, "#\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
52
92.86%
6
75.00%
Jiri Olsa
3
5.36%
1
12.50%
Frédéric Weisbecker
1
1.79%
1
12.50%
Total
56
100.00%
8
100.00%



static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m,
				   unsigned int flags)
{
	bool tgid = flags & TRACE_ITER_RECORD_TGID;

	print_event_info(buf, m);

	seq_printf(m, "#           TASK-PID   CPU#   %s  TIMESTAMP  FUNCTION\n", tgid ? "TGID     " : "");
	seq_printf(m, "#              | |       |    %s     |         |\n",	 tgid ? "  |      " : "");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
32
53.33%
1
12.50%
Steven Rostedt
25
41.67%
5
62.50%
Frédéric Weisbecker
2
3.33%
1
12.50%
Ingo Molnar
1
1.67%
1
12.50%
Total
60
100.00%
8
100.00%



static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m,
				       unsigned int flags)
{
	bool tgid = flags & TRACE_ITER_RECORD_TGID;
	const char tgid_space[] = "          ";
	const char space[] = "  ";

	seq_printf(m, "#                          %s  _-----=> irqs-off\n",
		   tgid ? tgid_space : space);
	seq_printf(m, "#                          %s / _----=> need-resched\n",
		   tgid ? tgid_space : space);
	seq_printf(m, "#                          %s| / _---=> hardirq/softirq\n",
		   tgid ? tgid_space : space);
	seq_printf(m, "#                          %s|| / _--=> preempt-depth\n",
		   tgid ? tgid_space : space);
	seq_printf(m, "#                          %s||| /     delay\n",
		   tgid ? tgid_space : space);
	seq_printf(m, "#           TASK-PID   CPU#%s||||    TIMESTAMP  FUNCTION\n",
		   tgid ? "   TGID   " : space);
	seq_printf(m, "#              | |       | %s||||       |         |\n",
		   tgid ? "     |    " : space);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Joel Fernandes
80
60.61%
1
14.29%
Steven Rostedt
48
36.36%
4
57.14%
Frédéric Weisbecker
4
3.03%
2
28.57%
Total
132
100.00%
7
100.00%


void

print_trace_header(struct seq_file *m, struct trace_iterator *iter)
{
	unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK);
	struct trace_buffer *buf = iter->trace_buffer;
	struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu);
	struct tracer *type = iter->trace;
	unsigned long entries;
	unsigned long total;
	const char *name = "preemption";

	name = type->name;

	get_total_entries(buf, &total, &entries);

	seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
		   name, UTS_RELEASE);
	seq_puts(m, "# -----------------------------------"
		 "---------------------------------\n");
	seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |"
		   " (M:%s VP:%d, KP:%d, SP:%d HP:%d",
		   nsecs_to_usecs(data->saved_latency),
		   entries,
		   total,
		   buf->cpu,
#if defined(CONFIG_PREEMPT_NONE)
		   "server",
#elif defined(CONFIG_PREEMPT_VOLUNTARY)
		   "desktop",
#elif defined(CONFIG_PREEMPT)
		   "preempt",
#else
		   "unknown",
#endif
		   /* These are reserved for later use */
		   0, 0, 0, 0);
#ifdef CONFIG_SMP
	seq_printf(m, " #P:%d)\n", num_online_cpus());
#else
	seq_puts(m, ")\n");
#endif
	seq_puts(m, "#    -----------------\n");
	seq_printf(m, "#    | task: %.16s-%d "
		   "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n",
		   data->comm, data->pid,
		   from_kuid_munged(seq_user_ns(m), data->uid), data->nice,
		   data->policy, data->rt_priority);
	seq_puts(m, "#    -----------------\n");

	if (data->critical_start) {
		seq_puts(m, "#  => started at: ");
		seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags);
		trace_print_seq(m, &iter->seq);
		seq_puts(m, "\n#  => ended at:   ");
		seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
		trace_print_seq(m, &iter->seq);
		seq_puts(m, "\n#\n");
	}

	seq_puts(m, "#\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
268
79.76%
21
58.33%
Frédéric Weisbecker
19
5.65%
3
8.33%
Motohiro Kosaki
9
2.68%
1
2.78%
Ingo Molnar
9
2.68%
3
8.33%
Markus Metzger
6
1.79%
1
2.78%
Eric W. Biedermann
6
1.79%
1
2.78%
Török Edwin
5
1.49%
1
2.78%
David S. Miller
5
1.49%
1
2.78%
Jiri Olsa
4
1.19%
1
2.78%
Hiraku Toyooka
3
0.89%
1
2.78%
Julia Lawall
1
0.30%
1
2.78%
Peter Zijlstra
1
0.30%
1
2.78%
Total
336
100.00%
36
100.00%



static void test_cpu_buff_start(struct trace_iterator *iter)
{
	struct trace_seq *s = &iter->seq;
	struct trace_array *tr = iter->tr;

	if (!(tr->trace_flags & TRACE_ITER_ANNOTATE))
		return;

	if (!(iter->iter_flags & TRACE_FILE_ANNOTATE))
		return;

	if (cpumask_available(iter->started) &&
	    cpumask_test_cpu(iter->cpu, iter->started))
		return;

	if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries)
		return;

	if (cpumask_available(iter->started))
		cpumask_set_cpu(iter->cpu, iter->started);

	/* Don't print started cpu buffer for the first entry of the trace */
	if (iter->idx > 1)
		trace_seq_printf(s, "##### CPU %u buffer started ####\n",
				iter->cpu);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
107
80.45%
10
62.50%
Sasha Levin
10
7.52%
1
6.25%
Frédéric Weisbecker
6
4.51%
1
6.25%
Matthias Kaehlcke
6
4.51%
1
6.25%
Ingo Molnar
2
1.50%
1
6.25%
Hiraku Toyooka
1
0.75%
1
6.25%
Pekka Paalanen
1
0.75%
1
6.25%
Total
133
100.00%
16
100.00%



static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
{
	struct trace_array *tr = iter->tr;
	struct trace_seq *s = &iter->seq;
	unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK);
	struct trace_entry *entry;
	struct trace_event *event;

	entry = iter->ent;

	test_cpu_buff_start(iter);

	event = ftrace_find_event(entry->type);

	if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) {
		if (iter->iter_flags & TRACE_FILE_LAT_FMT)
			trace_print_lat_context(iter);
		else
			trace_print_context(iter);
	}

	if (trace_seq_has_overflowed(s))
		return TRACE_TYPE_PARTIAL_LINE;

	if (event)
		return event->funcs->trace(iter, sym_flags, event);

	trace_seq_printf(s, "Unknown type %d\n", entry->type);

	return trace_handle_return(s);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
123
83.67%
9
56.25%
Frédéric Weisbecker
12
8.16%
3
18.75%
Ingo Molnar
7
4.76%
2
12.50%
Arnaldo Carvalho de Melo
5
3.40%
2
12.50%
Total
147
100.00%
16
100.00%



static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
{
	struct trace_array *tr = iter->tr;
	struct trace_seq *s = &iter->seq;
	struct trace_entry *entry;
	struct trace_event *event;

	entry = iter->ent;

	if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO)
		trace_seq_printf(s, "%d %d %llu ",
				 entry->pid, iter->cpu, iter->ts);

	if (trace_seq_has_overflowed(s))
		return TRACE_TYPE_PARTIAL_LINE;

	event = ftrace_find_event(entry->type);
	if (event)
		return event->funcs->raw(iter, 0, event);

	trace_seq_printf(s, "%d ?\n", entry->type);

	return trace_handle_return(s);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
81
63.28%
7
46.67%
Ingo Molnar
36
28.12%
2
13.33%
Frédéric Weisbecker
5
3.91%
2
13.33%
Peter Zijlstra
3
2.34%
2
13.33%
Arnaldo Carvalho de Melo
3
2.34%
2
13.33%
Total
128
100.00%
15
100.00%



static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
{
	struct trace_array *tr = iter->tr;
	struct trace_seq *s = &iter->seq;
	unsigned char newline = '\n';
	struct trace_entry *entry;
	struct trace_event *event;

	entry = iter->ent;

	if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) {
		SEQ_PUT_HEX_FIELD(s, entry->pid);
		SEQ_PUT_HEX_FIELD(s, iter->cpu);
		SEQ_PUT_HEX_FIELD(s, iter->ts);
		if (trace_seq_has_overflowed(s))
			return TRACE_TYPE_PARTIAL_LINE;
	}

	event = ftrace_find_event(entry->type);
	if (event) {
		enum print_line_t ret = event->funcs->hex(iter, 0, event);
		if (ret != TRACE_TYPE_HANDLED)
			return ret;
	}

	SEQ_PUT_FIELD(s, newline);

	return trace_handle_return(s);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
105
68.18%
8
50.00%
Ingo Molnar
27
17.53%
2
12.50%
Arnaldo Carvalho de Melo
11
7.14%
3
18.75%
Frédéric Weisbecker
8
5.19%
1
6.25%
Peter Zijlstra
3
1.95%
2
12.50%
Total
154
100.00%
16
100.00%



static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
{
	struct trace_array *tr = iter->tr;
	struct trace_seq *s = &iter->seq;
	struct trace_entry *entry;
	struct trace_event *event;

	entry = iter->ent;

	if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) {
		SEQ_PUT_FIELD(s, entry->pid);
		SEQ_PUT_FIELD(s, iter->cpu);
		SEQ_PUT_FIELD(s, iter->ts);
		if (trace_seq_has_overflowed(s))
			return TRACE_TYPE_PARTIAL_LINE;
	}

	event = ftrace_find_event(entry->type);
	return event ? event->funcs->binary(iter, 0, event) :
		TRACE_TYPE_HANDLED;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
51
42.15%
9
45.00%
Ingo Molnar
47
38.84%
3
15.00%
Slava Pestov
11
9.09%
1
5.00%
Arnaldo Carvalho de Melo
5
4.13%
3
15.00%
Frédéric Weisbecker
5
4.13%
2
10.00%
Peter Zijlstra
1
0.83%
1
5.00%
Arnd Bergmann
1
0.83%
1
5.00%
Total
121
100.00%
20
100.00%



int trace_empty(struct trace_iterator *iter)
{
	struct ring_buffer_iter *buf_iter;
	int cpu;

	/* If we are looking at one CPU buffer, only check that one */
	if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
		cpu = iter->cpu_file;
		buf_iter = trace_buffer_iter(iter, cpu);
		if (buf_iter) {
			if (!ring_buffer_iter_empty(buf_iter))
				return 0;
		} else {
			if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu))
				return 0;
		}
		return 1;
	}

	for_each_tracing_cpu(cpu) {
		buf_iter = trace_buffer_iter(iter, cpu);
		if (buf_iter) {
			if (!ring_buffer_iter_empty(buf_iter))
				return 0;
		} else {
			if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu))
				return 0;
		}
	}

	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
107
76.98%
8
72.73%
Ingo Molnar
31
22.30%
2
18.18%
Frédéric Weisbecker
1
0.72%
1
9.09%
Total
139
100.00%
11
100.00%

/*  Called with trace_event_read_lock() held. */


enum print_line_t print_trace_line(struct trace_iterator *iter)
{
	struct trace_array *tr = iter->tr;
	unsigned long trace_flags = tr->trace_flags;
	enum print_line_t ret;

	if (iter->lost_events) {
		trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
				 iter->cpu, iter->lost_events);
		if (trace_seq_has_overflowed(&iter->seq))
			return TRACE_TYPE_PARTIAL_LINE;
	}

	if (iter->trace && iter->trace->print_line) {
		ret = iter->trace->print_line(iter);
		if (ret != TRACE_TYPE_UNHANDLED)
			return ret;
	}

	if (iter->ent->type == TRACE_BPUTS &&
			trace_flags & TRACE_ITER_PRINTK &&
			trace_flags & TRACE_ITER_PRINTK_MSGONLY)
		return trace_print_bputs_msg_only(iter);

	if (iter->ent->type == TRACE_BPRINT &&
			trace_flags & TRACE_ITER_PRINTK &&
			trace_flags & TRACE_ITER_PRINTK_MSGONLY)
		return trace_print_bprintk_msg_only(iter);

	if (iter->ent->type == TRACE_PRINT &&
			trace_flags & TRACE_ITER_PRINTK &&
			trace_flags & TRACE_ITER_PRINTK_MSGONLY)
		return trace_print_printk_msg_only(iter);

	if (trace_flags & TRACE_ITER_BIN)
		return print_bin_fmt(iter);

	if (trace_flags & TRACE_ITER_HEX)
		return print_hex_fmt(iter);

	if (trace_flags & TRACE_ITER_RAW)
		return print_raw_fmt(iter);

	return print_trace_fmt(iter);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
68
31.05%
5
27.78%
Ingo Molnar
60
27.40%
5
27.78%
Frédéric Weisbecker
54
24.66%
3
16.67%
Thomas Gleixner
19
8.68%
1
5.56%
Rusty Russell
14
6.39%
1
5.56%
Vaibhav Nagarnaik
2
0.91%
1
5.56%
Li Zefan
1
0.46%
1
5.56%
Jiri Olsa
1
0.46%
1
5.56%
Total
219
100.00%
18
100.00%



void trace_latency_header(struct seq_file *m)
{
	struct trace_iterator *iter = m->private;
	struct trace_array *tr = iter->tr;

	/* print nothing if the buffers are empty */
	if (trace_empty(iter))
		return;

	if (iter->iter_flags & TRACE_FILE_LAT_FMT)
		print_trace_header(m, iter);

	if (!(tr->trace_flags & TRACE_ITER_VERBOSE))
		print_lat_help_header(m);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
33
48.53%
3
60.00%
Jiri Olsa
31
45.59%
1
20.00%
Li Zefan
4
5.88%
1
20.00%
Total
68
100.00%
5
100.00%



void trace_default_header(struct seq_file *m)
{
	struct trace_iterator *iter = m->private;
	struct trace_array *tr = iter->tr;
	unsigned long trace_flags = tr->trace_flags;

	if (!(trace_flags & TRACE_ITER_CONTEXT_INFO))
		return;

	if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
		/* print nothing if the buffers are empty */
		if (trace_empty(iter))
			return;
		print_trace_header(m, iter);
		if (!(trace_flags & TRACE_ITER_VERBOSE))
			print_lat_help_header(m);
	} else {
		if (!(trace_flags & TRACE_ITER_VERBOSE)) {
			if (trace_flags & TRACE_ITER_IRQ_INFO)
				print_func_help_header_irq(iter->trace_buffer,
							   m, trace_flags);
			else
				print_func_help_header(iter->trace_buffer, m,
						       trace_flags);
		}
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jiri Olsa
70
54.26%
2
18.18%
Steven Rostedt
40
31.01%
6
54.55%
Frédéric Weisbecker
13
10.08%
1
9.09%
Joel Fernandes
4
3.10%
1
9.09%
Li Zefan
2
1.55%
1
9.09%
Total
129
100.00%
11
100.00%



static void test_ftrace_alive(struct seq_file *m)
{
	if (!ftrace_is_dead())
		return;
	seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"
		    "#          MAY BE MISSING FUNCTION EVENTS\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
14
53.85%
1
25.00%
Li Zefan
7
26.92%
1
25.00%
Frédéric Weisbecker
4
15.38%
1
25.00%
Rasmus Villemoes
1
3.85%
1
25.00%
Total
26
100.00%
4
100.00%

#ifdef CONFIG_TRACER_MAX_TRACE


static void show_snapshot_main_help(struct seq_file *m)
{
	seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"
		    "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"
		    "#                      Takes a snapshot of the main buffer.\n"
		    "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"
		    "#                      (Doesn't have to be '2' works with any number that\n"
		    "#                       is not a '0' or '1')\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
15
65.22%
3
50.00%
Frédéric Weisbecker
6
26.09%
1
16.67%
Rasmus Villemoes
1
4.35%
1
16.67%
Wang YanQing
1
4.35%
1
16.67%
Total
23
100.00%
6
100.00%



static void show_snapshot_percpu_help(struct seq_file *m)
{
	seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n");
#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
	seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"
		    "#                      Takes a snapshot of the main buffer for this cpu.\n");
#else
	seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n"
		    "#                     Must use main snapshot file to allocate.\n");
#endif
	seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"
		    "#                      (Doesn't have to be '2' works with any number that\n"
		    "#                       is not a '0' or '1')\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
42
84.00%
6
66.67%
Rasmus Villemoes
4
8.00%
1
11.11%
Li Zefan
2
4.00%
1
11.11%
David Sharp
2
4.00%
1
11.11%
Total
50
100.00%
9
100.00%



static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter)
{
	if (iter->tr->allocated_snapshot)
		seq_puts(m, "#\n# * Snapshot is allocated *\n#\n");
	else
		seq_puts(m, "#\n# * Snapshot is freed *\n#\n");

	seq_puts(m, "# Snapshot commands:\n");
	if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
		show_snapshot_main_help(m);
	else
		show_snapshot_percpu_help(m);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
56
86.15%
7
70.00%
Rasmus Villemoes
3
4.62%
1
10.00%
Ingo Molnar
3
4.62%
1
10.00%
Frédéric Weisbecker
3
4.62%
1
10.00%
Total
65
100.00%
10
100.00%

#else
/* Should never be called */


static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { }
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
16
100.00%
2
100.00%
Total
16
100.00%
2
100.00%

#endif



static int s_show(struct seq_file *m, void *v)
{
	struct trace_iterator *iter = v;
	int ret;

	if (iter->ent == NULL) {
		if (iter->tr) {
			seq_printf(m, "# tracer: %s\n", iter->trace->name);
			seq_puts(m, "#\n");
			test_ftrace_alive(m);
		}
		if (iter->snapshot && trace_empty(iter))
			print_snapshot_help(m, iter);
		else if (iter->trace && iter->trace->print_header)
			iter->trace->print_header(m);
		else
			trace_default_header(m);

	} else if (iter->leftover) {
		/*
                 * If we filled the seq_file buffer earlier, we
                 * want to just show it now.
                 */
		ret = trace_print_seq(m, &iter->seq);

		/* ret should this time be zero, but you never know */
		iter->leftover = ret;

	} else {
		print_trace_line(iter);
		ret = trace_print_seq(m, &iter->seq);
		/*
                 * If we overflow the seq_file buffer, then it will
                 * ask us for this data again at start up.
                 * Use that instead.
                 *  ret is 0 if seq_file write succeeded.
                 *        -1 otherwise.
                 */
		iter->leftover = ret;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
142
82.08%
8
61.54%
Markus Metzger
17
9.83%
1
7.69%
Li Zefan
9
5.20%
1
7.69%
Frédéric Weisbecker
3
1.73%
1
7.69%
Ingo Molnar
1
0.58%
1
7.69%
Jiri Olsa
1
0.58%
1
7.69%
Total
173
100.00%
13
100.00%

/*
 * Should be used after trace_array_get(), trace_types_lock
 * ensures that i_cdev was already initialized.
 */


static inline int tracing_get_cpu(struct inode *inode)
{
	if (inode->i_cdev) /* See trace_create_cpu_file() */
		return (long)inode->i_cdev - 1;
	return RING_BUFFER_ALL_CPUS;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Oleg Nesterov
32
100.00%
1
100.00%
Total
32
100.00%
1
100.00%


static const struct seq_operations tracer_seq_ops = {
	.start		= s_start,
	.next		= s_next,
	.stop		= s_stop,
	.show		= s_show,
};


static struct trace_iterator *

__tracing_open(struct inode *inode, struct file *file, bool snapshot)
{
	struct trace_array *tr = inode->i_private;
	struct trace_iterator *iter;
	int cpu;

	if (tracing_disabled)
		return ERR_PTR(-ENODEV);

	iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter));
	if (!iter)
		return ERR_PTR(-ENOMEM);

	iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter),
				    GFP_KERNEL);
	if (!iter->buffer_iter)
		goto release;

	/*
         * We make a copy of the current tracer to avoid concurrent
         * changes on it while we are reading.
         */
	mutex_lock(&trace_types_lock);
	iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL);
	if (!iter->trace)
		goto fail;

	*iter->trace = *tr->current_trace;

	if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL))
		goto fail;

	iter->tr = tr;

#ifdef CONFIG_TRACER_MAX_TRACE
	/* Currently only the top directory has a snapshot */
	if (tr->current_trace->print_max || snapshot)
		iter->trace_buffer = &tr->max_buffer;
	else
#endif
		iter->trace_buffer = &tr->trace_buffer;
	iter->snapshot = snapshot;
	iter->pos = -1;
	iter->cpu_file = tracing_get_cpu(inode);
	mutex_init(&iter->mutex);

	/* Notify the tracer early; before we stop tracing. */
	if (iter->trace && iter->trace->open)
		iter->trace->open(iter);

	/* Annotate start of buffers if we had overruns */
	if (ring_buffer_overruns(iter->trace_buffer->buffer))
		iter->iter_flags |= TRACE_FILE_ANNOTATE;

	/* Output in nanoseconds only if we are using a clock in nanoseconds. */
	if (trace_clocks[tr->clock_id].in_ns)
		iter->iter_flags |= TRACE_FILE_TIME_IN_NS;

	/* stop the trace while dumping if we are not opening "snapshot" */
	if (!iter->snapshot)
		tracing_stop_tr(tr);

	if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
		for_each_tracing_cpu(cpu) {
			iter->buffer_iter[cpu] =
				ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
		}
		ring_buffer_read_prepare_sync();
		for_each_tracing_cpu(cpu) {
			ring_buffer_read_start(iter->buffer_iter[cpu]);
			tracing_iter_reset(iter, cpu);
		}
	} else {
		cpu = iter->cpu_file;
		iter->buffer_iter[cpu] =
			ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
		ring_buffer_read_prepare_sync();
		ring_buffer_read_start(iter->buffer_iter[cpu]);
		tracing_iter_reset(iter, cpu);
	}

	mutex_unlock(&trace_types_lock);

	return iter;

 fail:
	mutex_unlock(&trace_types_lock);
	kfree(iter->trace);
	kfree(iter->buffer_iter);
release:
	seq_release_private(inode, file);
	return ERR_PTR(-ENOMEM);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
167
36.15%
10
32.26%
Frédéric Weisbecker
76
16.45%
3
9.68%
Hiraku Toyooka
54
11.69%
2
6.45%
Avadh Patel
34
7.36%
1
3.23%
David S. Miller
20
4.33%
1
3.23%
Markus Metzger
19
4.11%
1
3.23%
Oleg Nesterov
18
3.90%
1
3.23%
David Sharp
15
3.25%
1
3.23%
Jiri Olsa
14
3.03%
1
3.23%
Ingo Molnar
10
2.16%
1
3.23%
Vaibhav Nagarnaik
8
1.73%
1
3.23%
Dan Carpenter
8
1.73%
1
3.23%
Arnaldo Carvalho de Melo
7
1.52%
1
3.23%
Julia Lawall
4
0.87%
1
3.23%
Gil Fruchter
3
0.65%
2
6.45%
Yoshihiro Yunomae
3
0.65%
1
3.23%
Li Zefan
1
0.22%
1
3.23%
Arnd Bergmann
1
0.22%
1
3.23%
Total
462
100.00%
31
100.00%



int tracing_open_generic(struct inode *inode, struct file *filp)
{
	if (tracing_disabled)
		return -ENODEV;

	filp->private_data = inode->i_private;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
33
97.06%
4
80.00%
Vaibhav Nagarnaik
1
2.94%
1
20.00%
Total
34
100.00%
5
100.00%



bool tracing_is_disabled(void)
{
	return (tracing_disabled) ? true: false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Geyslan G. Bem
16
100.00%
1
100.00%
Total
16
100.00%
1
100.00%

/*
 * Open and update trace_array ref count.
 * Must have the current trace_array passed to it.
 */


static int tracing_open_generic_tr(struct inode *inode, struct file *filp)
{
	struct trace_array *tr = inode->i_private;

	if (tracing_disabled)
		return -ENODEV;

	if (trace_array_get(tr) < 0)
		return -ENODEV;

	filp->private_data = inode->i_private;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
57
100.00%
2
100.00%
Total
57
100.00%
2
100.00%



static int tracing_release(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;
	struct seq_file *m = file->private_data;
	struct trace_iterator *iter;
	int cpu;

	if (!(file->f_mode & FMODE_READ)) {
		trace_array_put(tr);
		return 0;
	}

	/* Writes do not use seq_file */
	iter = m->private;
	mutex_lock(&trace_types_lock);

	for_each_tracing_cpu(cpu) {
		if (iter->buffer_iter[cpu])
			ring_buffer_read_finish(iter->buffer_iter[cpu]);
	}

	if (iter->trace && iter->trace->close)
		iter->trace->close(iter);

	if (!iter->snapshot)
		/* reenable tracing if it was previously enabled */
		tracing_start_tr(tr);

	__trace_array_put(tr);

	mutex_unlock(&trace_types_lock);

	mutex_destroy(&iter->mutex);
	free_cpumask_var(iter->started);
	kfree(iter->trace);
	kfree(iter->buffer_iter);
	seq_release_private(inode, file);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
105
56.76%
7
41.18%
Vaibhav Nagarnaik
33
17.84%
2
11.76%
Frédéric Weisbecker
15
8.11%
2
11.76%
Oleg Nesterov
10
5.41%
1
5.88%
Hiraku Toyooka
6
3.24%
1
5.88%
Motohiro Kosaki
6
3.24%
1
5.88%
Alexander Z Lam
5
2.70%
1
5.88%
Jiri Olsa
4
2.16%
1
5.88%
Hannes Eder
1
0.54%
1
5.88%
Total
185
100.00%
17
100.00%



static int tracing_release_generic_tr(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;

	trace_array_put(tr);
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%



static int tracing_single_release_tr(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;

	trace_array_put(tr);

	return single_release(inode, file);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
38
100.00%
1
100.00%
Total
38
100.00%
1
100.00%



static int tracing_open(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;
	struct trace_iterator *iter;
	int ret = 0;

	if (trace_array_get(tr) < 0)
		return -ENODEV;

	/* If this file was open for write, then erase contents */
	if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
		int cpu = tracing_get_cpu(inode);
		struct trace_buffer *trace_buf = &tr->trace_buffer;

#ifdef CONFIG_TRACER_MAX_TRACE
		if (tr->current_trace->print_max)
			trace_buf = &tr->max_buffer;
#endif

		if (cpu == RING_BUFFER_ALL_CPUS)
			tracing_reset_online_cpus(trace_buf);
		else
			tracing_reset(trace_buf, cpu);
	}

	if (file->f_mode & FMODE_READ) {
		iter = __tracing_open(inode, file, false);
		if (IS_ERR(iter))
			ret = PTR_ERR(iter);
		else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT)
			iter->iter_flags |= TRACE_FILE_LAT_FMT;
	}

	if (ret < 0)
		trace_array_put(tr);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
145
76.32%
10
71.43%
Bo Yan
32
16.84%
1
7.14%
Oleg Nesterov
10
5.26%
1
7.14%
Hiraku Toyooka
2
1.05%
1
7.14%
Vaibhav Nagarnaik
1
0.53%
1
7.14%
Total
190
100.00%
14
100.00%

/*
 * Some tracers are not suitable for instance buffers.
 * A tracer is always available for the global array (toplevel)
 * or if it explicitly states that it is.
 */

static bool

trace_ok_for_array(struct tracer *t, struct trace_array *tr)
{
	return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
29
100.00%
1
100.00%
Total
29
100.00%
1
100.00%

/* Find the next tracer that this trace array may use */

static struct tracer *

get_tracer_for_array(struct trace_array *tr, struct tracer *t)
{
	while (t && !trace_ok_for_array(t, tr))
		t = t->next;

	return t;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
39
100.00%
1
100.00%
Total
39
100.00%
1
100.00%


static void *

t_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct trace_array *tr = m->private;
	struct tracer *t = v;

	(*pos)++;

	if (t)
		t = get_tracer_for_array(tr, t->next);

	return t;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
58
96.67%
3
60.00%
Li Zefan
1
1.67%
1
20.00%
Ingo Molnar
1
1.67%
1
20.00%
Total
60
100.00%
5
100.00%



static void *t_start(struct seq_file *m, loff_t *pos)
{
	struct trace_array *tr = m->private;
	struct tracer *t;
	loff_t l = 0;

	mutex_lock(&trace_types_lock);

	t = get_tracer_for_array(tr, trace_types);
	for (; t && l < *pos; t = t_next(m, t, &l))
			;

	return t;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
74
97.37%
3
75.00%
Peter Zijlstra
2
2.63%
1
25.00%
Total
76
100.00%
4
100.00%



static void t_stop(struct seq_file *m, void *p)
{
	mutex_unlock(&trace_types_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
18
85.71%
1
50.00%
Frédéric Weisbecker
3
14.29%
1
50.00%
Total
21
100.00%
2
100.00%



static int t_show(struct seq_file *m, void *v)
{
	struct tracer *t = v;

	if (!t)
		return 0;

	seq_puts(m, t->name);
	if (t->next)
		seq_putc(m, ' ');
	else
		seq_putc(m, '\n');

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
51
80.95%
2
33.33%
Motohiro Kosaki
6
9.52%
1
16.67%
Vaibhav Nagarnaik
3
4.76%
1
16.67%
Hiraku Toyooka
2
3.17%
1
16.67%
Rasmus Villemoes
1
1.59%
1
16.67%
Total
63
100.00%
6
100.00%


static const struct seq_operations show_traces_seq_ops = {
	.start		= t_start,
	.next		= t_next,
	.stop		= t_stop,
	.show		= t_show,
};



static int show_traces_open(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;
	struct seq_file *m;
	int ret;

	if (tracing_disabled)
		return -ENODEV;

	ret = seq_open(file, &show_traces_seq_ops);
	if (ret)
		return ret;

	m = file->private_data;
	m->private = tr;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
68
93.15%
3
60.00%
Frédéric Weisbecker
3
4.11%
1
20.00%
Peter Zijlstra
2
2.74%
1
20.00%
Total
73
100.00%
5
100.00%


static ssize_t

tracing_write_stub(struct file *filp, const char __user *ubuf,
		   size_t count, loff_t *ppos)
{
	return count;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Peter Zijlstra
21
77.78%
1
50.00%
Steven Rostedt
6
22.22%
1
50.00%
Total
27
100.00%
2
100.00%



loff_t tracing_lseek(struct file *file, loff_t offset, int whence)
{
	int ret;

	if (file->f_mode & FMODE_READ)
		ret = seq_lseek(file, offset, whence);
	else
		file->f_pos = ret = 0;

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Slava Pestov
23
46.00%
1
25.00%
Steven Rostedt
18
36.00%
1
25.00%
Peter Zijlstra
8
16.00%
1
25.00%
Frédéric Weisbecker
1
2.00%
1
25.00%
Total
50
100.00%
4
100.00%


static const struct file_operations tracing_fops = {
	.open		= tracing_open,
	.read		= seq_read,
	.write		= tracing_write_stub,
	.llseek		= tracing_lseek,
	.release	= tracing_release,
};


static const struct file_operations show_traces_fops = {
	.open		= show_traces_open,
	.read		= seq_read,
	.release	= seq_release,
	.llseek		= seq_lseek,
};

/*
 * The tracer itself will not take this lock, but still we want
 * to provide a consistent cpumask to user-space:
 */
static DEFINE_MUTEX(tracing_cpumask_update_lock);

/*
 * Temporary storage for the character representation of the
 * CPU bitmask (and one more byte for the newline):
 */

static char mask_str[NR_CPUS + 1];


static ssize_t

tracing_cpumask_read(struct file *filp, char __user *ubuf,
		     size_t count, loff_t *ppos)
{
	struct trace_array *tr = file_inode(filp)->i_private;
	int len;

	mutex_lock(&tracing_cpumask_update_lock);

	len = snprintf(mask_str, count, "%*pb\n",
		       cpumask_pr_args(tr->tracing_cpumask));
	if (len >= count) {
		count = -EINVAL;
		goto out_err;
	}
	count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1);

out_err:
	mutex_unlock(&tracing_cpumask_update_lock);

	return count;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
43
40.57%
2
33.33%
Ingo Molnar
41
38.68%
2
33.33%
Alexander Z Lam
14
13.21%
1
16.67%
Tejun Heo
8
7.55%
1
16.67%
Total
106
100.00%
6
100.00%


static ssize_t

tracing_cpumask_write(struct file *filp, const char __user *ubuf,
		      size_t count, loff_t *ppos)
{
	struct trace_array *tr = file_inode(filp)->i_private;
	cpumask_var_t tracing_cpumask_new;
	int err, cpu;

	if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
		return -ENOMEM;

	err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
	if (err)
		goto err_unlock;

	mutex_lock(&tracing_cpumask_update_lock);

	local_irq_disable();
	arch_spin_lock(&tr->max_lock);
	for_each_tracing_cpu(cpu) {
		/*
                 * Increase/decrease the disabled counter if we are
                 * about to flip a bit in the cpumask:
                 */
		if (cpumask_test_cpu(cpu, tr->tracing_cpumask) &&
				!cpumask_test_cpu(cpu, tracing_cpumask_new)) {
			atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled);
			ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu);
		}
		if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) &&
				cpumask_test_cpu(cpu, tracing_cpumask_new)) {
			atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled);
			ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu);
		}
	}
	arch_spin_unlock(&tr->max_lock);
	local_irq_enable();

	cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new);

	mutex_unlock(&tracing_cpumask_update_lock);
	free_cpumask_var(tracing_cpumask_new);

	return count;

err_unlock:
	free_cpumask_var(tracing_cpumask_new);

	return err;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
92
37.86%
13
52.00%
Ingo Molnar
67
27.57%
2
8.00%
Frédéric Weisbecker
28
11.52%
2
8.00%
Rusty Russell
25
10.29%
2
8.00%
Vaibhav Nagarnaik
12
4.94%
1
4.00%
Alexander Z Lam
10
4.12%
1
4.00%
Arnd Bergmann
4
1.65%
1
4.00%
Thomas Gleixner
3
1.23%
2
8.00%
Li Zefan
2
0.82%
1
4.00%
Total
243
100.00%
25
100.00%


static const struct file_operations tracing_cpumask_fops = {
	.open		= tracing_open_generic_tr,
	.read		= tracing_cpumask_read,
	.write		= tracing_cpumask_write,
	.release	= tracing_release_generic_tr,
	.llseek		= generic_file_llseek,
};



static int tracing_trace_options_show(struct seq_file *m, void *v)
{
	struct tracer_opt *trace_opts;
	struct trace_array *tr = m->private;
	u32 tracer_flags;
	int i;

	mutex_lock(&trace_types_lock);
	tracer_flags = tr->current_trace->flags->val;
	trace_opts = tr->current_trace->flags->opts;

	for (i = 0; trace_options[i]; i++) {
		if (tr->trace_flags & (1 << i))
			seq_printf(m, "%s\n", trace_options[i]);
		else
			seq_printf(m, "no%s\n", trace_options[i]);
	}

	for (i = 0; trace_opts[i].name; i++) {
		if (tracer_flags & trace_opts[i].bit)
			seq_printf(m, "%s\n", trace_opts[i].name);
		else
			seq_printf(m, "no%s\n", trace_opts[i].name);
	}
	mutex_unlock(&trace_types_lock);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
100
55.25%
7
58.33%
Frédéric Weisbecker
67
37.02%
3
25.00%
Li Zefan
13
7.18%
1
8.33%
Rusty Russell
1
0.55%
1
8.33%
Total
181
100.00%
12
100.00%



static int __set_tracer_option(struct trace_array *tr,
			       struct tracer_flags *tracer_flags,
			       struct tracer_opt *opts, int neg)
{
	struct tracer *trace = tracer_flags->trace;
	int ret;

	ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg);
	if (ret)
		return ret;

	if (neg)
		tracer_flags->val &= ~opts->bit;
	else
		tracer_flags->val |= opts->bit;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Li Zefan
45
51.14%
1
16.67%
Soeren Sandmann Pedersen
24
27.27%
1
16.67%
Steven Rostedt
11
12.50%
1
16.67%
Frédéric Weisbecker
5
5.68%
1
16.67%
Chunyu Hu
2
2.27%
1
16.67%
Zhao Lei
1
1.14%
1
16.67%
Total
88
100.00%
6
100.00%

/* Try to assign a tracer specific option */


static int set_tracer_option(struct trace_array *tr, char *cmp, int neg)
{
	struct tracer *trace = tr->current_trace;
	struct tracer_flags *tracer_flags = trace->flags;
	struct tracer_opt *opts = NULL;
	int i;

	for (i = 0; tracer_flags->opts[i].name; i++) {
		opts = &tracer_flags->opts[i];

		if (strcmp(cmp, opts->name) == 0)
			return __set_tracer_option(tr, trace->flags, opts, neg);
	}

	return -EINVAL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Frédéric Weisbecker
61
57.01%
3
42.86%
Eduard - Gabriel Munteanu
25
23.36%
1
14.29%
Steven Rostedt
12
11.21%
1
14.29%
Li Zefan
6
5.61%
1
14.29%
Zhao Lei
3
2.80%
1
14.29%
Total
107
100.00%
7
100.00%

/* Some tracers require overwrite to stay enabled */


int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set)
{
	if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set)
		return -1;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
37
97.37%
2
66.67%
Pekka Paalanen
1
2.63%
1
33.33%
Total
38
100.00%
3
100.00%



int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
{
	/* do nothing if flag is already set */
	if (!!(tr->trace_flags & mask) == !!enabled)
		return 0;

	/* Give the tracer a chance to approve the change */
	if (tr->current_trace->flag_changed)
		if (tr->current_trace->flag_changed(tr, mask, !!enabled))
			return -EINVAL;

	if (enabled)
		tr->trace_flags |= mask;
	else
		tr->trace_flags &= ~mask;

	if (mask == TRACE_ITER_RECORD_CMD)
		trace_event_enable_cmd_record(enabled);

	if (mask == TRACE_ITER_RECORD_TGID) {
		if (!tgid_map)
			tgid_map = kzalloc((PID_MAX_DEFAULT + 1) * sizeof(*tgid_map),
					   GFP_KERNEL);
		if (!tgid_map) {
			tr->trace_flags &= ~TRACE_ITER_RECORD_TGID;
			return -ENOMEM;
		}

		trace_event_enable_tgid_record(enabled);
	}

	if (mask == TRACE_ITER_EVENT_FORK)
		trace_event_follow_fork(tr, enabled);

	if (mask == TRACE_ITER_FUNC_FORK)
		ftrace_pid_follow_fork(tr, enabled);

	if (mask == TRACE_ITER_OVERWRITE) {
		ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled);
#ifdef CONFIG_TRACER_MAX_TRACE
		ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled);
#endif
	}

	if (mask == TRACE_ITER_PRINTK) {
		trace_printk_start_stop_comm(enabled);
		trace_printk_control(enabled);
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
146
62.66%
13
59.09%
Joel Fernandes
55
23.61%
1
4.55%
David Sharp
7
3.00%
1
4.55%
Namhyung Kim
6
2.58%
1
4.55%
Frédéric Weisbecker
5
2.15%
1
4.55%
Li Zefan
5
2.15%
1
4.55%
Lai Jiangshan
4
1.72%
1
4.55%
Pekka Paalanen
2
0.86%
1
4.55%
Hiraku Toyooka
2
0.86%
1
4.55%
Eduard - Gabriel Munteanu
1
0.43%
1
4.55%
Total
233
100.00%
22
100.00%



static int trace_set_options(struct trace_array *tr, char *option)
{
	char *cmp;
	int neg = 0;
	int ret = -ENODEV;
	int i;
	size_t orig_len = strlen(option);

	cmp = strstrip(option);

	if (strncmp(cmp, "no", 2) == 0) {
		neg = 1;
		cmp += 2;
	}

	mutex_lock(&trace_types_lock);

	for (i = 0; trace_options[i]; i++) {
		if (strcmp(cmp, trace_options[i]) == 0) {
			ret = set_tracer_flag(tr, 1 << i, !neg);
			break;
		}
	}

	/* If no option could be set, test the specific tracer options */
	if (!trace_options[i])
		ret = set_tracer_option(tr, cmp, neg);

	mutex_unlock(&trace_types_lock);

	/*
         * If the first trailing whitespace is replaced with '\0' by strstrip,
         * turn it back into a space.
         */
	if (orig_len > strlen(option))
		option[strlen(option)] = ' ';

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
117
67.63%
11
55.00%
Jiaxing Wang
28
16.18%
1
5.00%
Frédéric Weisbecker
11
6.36%
2
10.00%
Ingo Molnar
6
3.47%
2
10.00%
Li Zefan
4
2.31%
1
5.00%
Pekka Paalanen
4
2.31%
1
5.00%
Jiri Olsa
2
1.16%
1
5.00%
Lai Jiangshan
1
0.58%
1
5.00%
Total
173
100.00%
20
100.00%



static void __init apply_trace_boot_options(void)
{
	char *buf = trace_boot_options_buf;
	char *option;

	while (true) {
		option = strsep(&buf, ",");

		if (!option)
			break;

		if (*option)
			trace_set_options(&global_trace, option);

		/* Put back the comma to allow this to be called again */
		if (buf)
			*(buf - 1) = ',';
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jiaxing Wang
68
100.00%
1
100.00%
Total
68
100.00%
1
100.00%


static ssize_t

tracing_trace_options_write(struct file *filp, const char __user *ubuf,
			size_t cnt, loff_t *ppos)
{
	struct seq_file *m = filp->private_data;
	struct trace_array *tr = m->private;
	char buf[64];
	int ret;

	if (cnt >= sizeof(buf))
		return -EINVAL;

	if (copy_from_user(buf, ubuf, cnt))
		return -EFAULT;

	buf[cnt] = 0;

	ret = trace_set_options(tr, buf);
	if (ret < 0)
		return ret;

	*ppos += cnt;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
102
91.07%
5
55.56%
Eduard - Gabriel Munteanu
3
2.68%
1
11.11%
Frédéric Weisbecker
3
2.68%
1
11.11%
Jiri Olsa
2
1.79%
1
11.11%
Ingo Molnar
2
1.79%
1
11.11%
Total
112
100.00%
9
100.00%



static int tracing_trace_options_open(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;
	int ret;

	if (tracing_disabled)
		return -ENODEV;

	if (trace_array_get(tr) < 0)
		return -ENODEV;

	ret = single_open(file, tracing_trace_options_show, inode->i_private);
	if (ret < 0)
		trace_array_put(tr);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
27
35.53%
3
50.00%
Li Zefan
23
30.26%
1
16.67%
Alexander Z Lam
19
25.00%
1
16.67%
Eduard - Gabriel Munteanu
7
9.21%
1
16.67%
Total
76
100.00%
6
100.00%


static const struct file_operations tracing_iter_fops = {
	.open		= tracing_trace_options_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= tracing_single_release_tr,
	.write		= tracing_trace_options_write,
};


static const char readme_msg[] =
	"tracing mini-HOWTO:\n\n"
	"# echo 0 > tracing_on : quick way to disable tracing\n"
	"# echo 1 > tracing_on : quick way to re-enable tracing\n\n"
	" Important files:\n"
	"  trace\t\t\t- The static contents of the buffer\n"
	"\t\t\t  To clear the buffer write into this file: echo > trace\n"
	"  trace_pipe\t\t- A consuming read to see the contents of the buffer\n"
	"  current_tracer\t- function and latency tracers\n"
	"  available_tracers\t- list of configured tracers for current_tracer\n"
	"  buffer_size_kb\t- view and modify size of per cpu buffer\n"
	"  buffer_total_size_kb  - view total size of all cpu buffers\n\n"
	"  trace_clock\t\t-change the clock used to order events\n"
	"       local:   Per cpu clock but may not be synced across CPUs\n"
	"      global:   Synced across CPUs but slows tracing down.\n"
	"     counter:   Not a clock, but just an increment\n"
	"      uptime:   Jiffy counter from time of boot\n"
	"        perf:   Same clock that perf events use\n"
#ifdef CONFIG_X86_64
	"     x86-tsc:   TSC cycle counter\n"
#endif
	"\n  trace_marker\t\t- Writes into this file writes into the kernel buffer\n"
	"\n  trace_marker_raw\t\t- Writes into this file writes binary data into the kernel buffer\n"
	"  tracing_cpumask\t- Limit which CPUs to trace\n"
	"  instances\t\t- Make sub-buffers with: mkdir instances/foo\n"
	"\t\t\t  Remove sub-buffer with rmdir\n"
	"  trace_options\t\t- Set format or modify how tracing happens\n"
	"\t\t\t  Disable an option by adding a suffix 'no' to the\n"
	"\t\t\t  option name\n"
	"  saved_cmdlines_size\t- echo command number in here to store comm-pid list\n"
#ifdef CONFIG_DYNAMIC_FTRACE
	"\n  available_filter_functions - list of functions that can be filtered on\n"
	"  set_ftrace_filter\t- echo function name in here to only trace these\n"
	"\t\t\t  functions\n"
	"\t     accepts: func_full_name or glob-matching-pattern\n"
	"\t     modules: Can select a group via module\n"
	"\t      Format: :mod:<module-name>\n"
	"\t     example: echo :mod:ext3 > set_ftrace_filter\n"
	"\t    triggers: a command to perform when function is hit\n"
	"\t      Format: <function>:<trigger>[:count]\n"
	"\t     trigger: traceon, traceoff\n"
	"\t\t      enable_event:<system>:<event>\n"
	"\t\t      disable_event:<system>:<event>\n"
#ifdef CONFIG_STACKTRACE
	"\t\t      stacktrace\n"
#endif
#ifdef CONFIG_TRACER_SNAPSHOT
	"\t\t      snapshot\n"
#endif
	"\t\t      dump\n"
	"\t\t      cpudump\n"
	"\t     example: echo do_fault:traceoff > set_ftrace_filter\n"
	"\t              echo do_trap:traceoff:3 > set_ftrace_filter\n"
	"\t     The first one will disable tracing every time do_fault is hit\n"
	"\t     The second will disable tracing at most 3 times when do_trap is hit\n"
	"\t       The first time do trap is hit and it disables tracing, the\n"
	"\t       counter will decrement to 2. If tracing is already disabled,\n"
	"\t       the counter will not decrement. It only decrements when the\n"
	"\t       trigger did work\n"
	"\t     To remove trigger without count:\n"
	"\t       echo '!<function>:<trigger> > set_ftrace_filter\n"
	"\t     To remove trigger with a count:\n"
	"\t       echo '!<function>:<trigger>:0 > set_ftrace_filter\n"
	"  set_ftrace_notrace\t- echo function name in here to never trace.\n"
	"\t    accepts: func_full_name, *func_end, func_begin*, *func_middle*\n"
	"\t    modules: Can select a group via module command :mod:\n"
	"\t    Does not accept triggers\n"
#endif /* CONFIG_DYNAMIC_FTRACE */
#ifdef CONFIG_FUNCTION_TRACER
	"  set_ftrace_pid\t- Write pid(s) to only function trace those pids\n"
	"\t\t    (function)\n"
#endif
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
	"  set_graph_function\t- Trace the nested calls of a function (function_graph)\n"
	"  set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n"
	"  max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n"
#endif
#ifdef CONFIG_TRACER_SNAPSHOT
	"\n  snapshot\t\t- Like 'trace' but shows the content of the static\n"
	"\t\t\t  snapshot buffer. Read the contents for more\n"
	"\t\t\t  information\n"
#endif
#ifdef CONFIG_STACK_TRACER
	"  stack_trace\t\t- Shows the max stack trace when active\n"
	"  stack_max_size\t- Shows current max stack size that was traced\n"
	"\t\t\t  Write into this file to reset the max size (trigger a\n"
	"\t\t\t  new trace)\n"
#ifdef CONFIG_DYNAMIC_FTRACE
	"  stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n"
	"\t\t\t  traces\n"
#endif
#endif /* CONFIG_STACK_TRACER */
#ifdef CONFIG_KPROBE_EVENTS
	"  kprobe_events\t\t- Add/remove/show the kernel dynamic events\n"
	"\t\t\t  Write into this file to define/undefine new trace events.\n"
#endif
#ifdef CONFIG_UPROBE_EVENTS
	"  uprobe_events\t\t- Add/remove/show the userspace dynamic events\n"
	"\t\t\t  Write into this file to define/undefine new trace events.\n"
#endif
#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
	"\t  accepts: event-definitions (one definition per line)\n"
	"\t   Format: p[:[<group>/]<event>] <place> [<args>]\n"
	"\t           r[maxactive][:[<group>/]<event>] <place> [<args>]\n"
	"\t           -:[<group>/]<event>\n"
#ifdef CONFIG_KPROBE_EVENTS
	"\t    place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
  "place (kretprobe): [<module>:]<symbol>[+<offset>]|<memaddr>\n"
#endif
#ifdef CONFIG_UPROBE_EVENTS
	"\t    place: <path>:<offset>\n"
#endif
	"\t     args: <name>=fetcharg[:type]\n"
	"\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n"
	"\t           $stack<index>, $stack, $retval, $comm\n"
	"\t     type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string,\n"
	"\t           b<bit-width>@<bit-offset>/<container-size>\n"
#endif
	"  events/\t\t- Directory containing all trace event subsystems:\n"
	"      enable\t\t- Write 0/1 to enable/disable tracing of all events\n"
	"  events/<system>/\t- Directory containing all trace events for <system>:\n"
	"      enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n"
	"\t\t\t  events\n"
	"      filter\t\t- If set, only events passing filter are traced\n"
	"  events/<system>/<event>/\t- Directory containing control files for\n"
	"\t\t\t  <event>:\n"
	"      enable\t\t- Write 0/1 to enable/disable tracing of <event>\n"
	"      filter\t\t- If set, only events passing filter are traced\n"
	"      trigger\t\t- If set, a command to perform when event is hit\n"
	"\t    Format: <trigger>[:count][if <filter>]\n"
	"\t   trigger: traceon, traceoff\n"
	"\t            enable_event:<system>:<event>\n"
	"\t            disable_event:<system>:<event>\n"
#ifdef CONFIG_HIST_TRIGGERS
	"\t            enable_hist:<system>:<event>\n"
	"\t            disable_hist:<system>:<event>\n"
#endif
#ifdef CONFIG_STACKTRACE
	"\t\t    stacktrace\n"
#endif
#ifdef CONFIG_TRACER_SNAPSHOT
	"\t\t    snapshot\n"
#endif
#ifdef CONFIG_HIST_TRIGGERS
	"\t\t    hist (see below)\n"
#endif
	"\t   example: echo traceoff > events/block/block_unplug/trigger\n"
	"\t            echo traceoff:3 > events/block/block_unplug/trigger\n"
	"\t            echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n"
	"\t                  events/block/block_unplug/trigger\n"
	"\t   The first disables tracing every time block_unplug is hit.\n"
	"\t   The second disables tracing the first 3 times block_unplug is hit.\n"
	"\t   The third enables the kmalloc event the first 3 times block_unplug\n"
	"\t     is hit and has value of greater than 1 for the 'nr_rq' event field.\n"
	"\t   Like function triggers, the counter is only decremented if it\n"
	"\t    enabled or disabled tracing.\n"
	"\t   To remove a trigger without a count:\n"
	"\t     echo '!<trigger> > <system>/<event>/trigger\n"
	"\t   To remove a trigger with a count:\n"
	"\t     echo '!<trigger>:0 > <system>/<event>/trigger\n"
	"\t   Filters can be ignored when removing a trigger.\n"
#ifdef CONFIG_HIST_TRIGGERS
	"      hist trigger\t- If set, event hits are aggregated into a hash table\n"
	"\t    Format: hist:keys=<field1[,field2,...]>\n"
	"\t            [:values=<field1[,field2,...]>]\n"
	"\t            [:sort=<field1[,field2,...]>]\n"
	"\t            [:size=#entries]\n"
	"\t            [:pause][:continue][:clear]\n"
	"\t            [:name=histname1]\n"
	"\t            [if <filter>]\n\n"
	"\t    When a matching event is hit, an entry is added to a hash\n"
	"\t    table using the key(s) and value(s) named, and the value of a\n"
	"\t    sum called 'hitcount' is incremented.  Keys and values\n"
	"\t    correspond to fields in the event's format description.  Keys\n"
	"\t    can be any field, or the special string 'stacktrace'.\n"
	"\t    Compound keys consisting of up to two fields can be specified\n"
	"\t    by the 'keys' keyword.  Values must correspond to numeric\n"
	"\t    fields.  Sort keys consisting of up to two fields can be\n"
	"\t    specified using the 'sort' keyword.  The sort direction can\n"
	"\t    be modified by appending '.descending' or '.ascending' to a\n"
	"\t    sort field.  The 'size' parameter can be used to specify more\n"
	"\t    or fewer than the default 2048 entries for the hashtable size.\n"
	"\t    If a hist trigger is given a name using the 'name' parameter,\n"
	"\t    its histogram data will be shared with other triggers of the\n"
	"\t    same name, and trigger hits will update this common data.\n\n"
	"\t    Reading the 'hist' file for the event will dump the hash\n"
	"\t    table in its entirety to stdout.  If there are multiple hist\n"
	"\t    triggers attached to an event, there will be a table for each\n"
	"\t    trigger in the output.  The table displayed for a named\n"
	"\t    trigger will be the same as any other instance having the\n"
	"\t    same name.  The default format used to display a given field\n"
	"\t    can be modified by appending any of the following modifiers\n"
	"\t    to the field name, as applicable:\n\n"
	"\t            .hex        display a number as a hex value\n"
	"\t            .sym        display an address as a symbol\n"
	"\t            .sym-offset display an address as a symbol and offset\n"
	"\t            .execname   display a common_pid as a program name\n"
	"\t            .syscall    display a syscall id as a syscall name\n\n"
	"\t            .log2       display log2 value rather than raw number\n\n"
	"\t    The 'pause' parameter can be used to pause an existing hist\n"
	"\t    trigger or to start a hist trigger but not log any events\n"
	"\t    until told to do so.  'continue' can be used to start or\n"
	"\t    restart a paused hist trigger.\n\n"
	"\t    The 'clear' parameter will clear the contents of a running\n"
	"\t    hist trigger and leave its current paused/active state\n"
	"\t    unchanged.\n\n"
	"\t    The enable_hist and disable_hist triggers can be used to\n"
	"\t    have one event conditionally start and stop another event's\n"
	"\t    already-attached hist trigger.  The syntax is analagous to\n"
	"\t    the enable_event and disable_event triggers.\n"
#endif
;


static ssize_t

tracing_readme_read(struct file *filp, char __user *ubuf,
		       size_t cnt, loff_t *ppos)
{
	return simple_read_from_buffer(ubuf, cnt, ppos,
					readme_msg, strlen(readme_msg));
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Ingo Molnar
40
100.00%
1
100.00%
Total
40
100.00%
1
100.00%


static const struct file_operations tracing_readme_fops = {
	.open		= tracing_open_generic,
	.read		= tracing_readme_read,
	.llseek		= generic_file_llseek,
};



static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos)
{
	int *ptr = v;

	if (*pos || m->count)
		ptr++;

	(*pos)++;

	for (; ptr <= &tgid_map[PID_MAX_DEFAULT]; ptr++) {
		if (trace_find_tgid(*ptr))
			return ptr;
	}

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Michael Sartain
74
100.00%
1
100.00%
Total
74
100.00%
1
100.00%



static void *saved_tgids_start(struct seq_file *m, loff_t *pos)
{
	void *v;
	loff_t l = 0;

	if (!tgid_map)
		return NULL;

	v = &tgid_map[0];
	while (l <= *pos) {
		v = saved_tgids_next(m, v, &l);
		if (!v)
			return NULL;
	}

	return v;
}

Contributors
Person
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CommitProp
Michael Sartain
73
100.00%
1
100.00%
Total
73
100.00%
1
100.00%



static void saved_tgids_stop(struct seq_file *m, void *v)
{
}

Contributors
Person
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CommitProp
Michael Sartain
14
100.00%
1
100.00%
Total
14
100.00%
1
100.00%



static int saved_tgids_show(struct seq_file *m, void *v)
{
	int pid = (int *)v - tgid_map;

	seq_printf(m, "%d %d\n", pid, trace_find_tgid(pid));
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Michael Sartain
43
100.00%
1
100.00%
Total
43
100.00%
1
100.00%


static const struct seq_operations tracing_saved_tgids_seq_ops = {
	.start		= saved_tgids_start,
	.stop		= saved_tgids_stop,
	.next		= saved_tgids_next,
	.show		= saved_tgids_show,
};



static int tracing_saved_tgids_open(struct inode *inode, struct file *filp)
{
	if (tracing_disabled)
		return -ENODEV;

	return seq_open(filp, &tracing_saved_tgids_seq_ops);
}


Contributors
Person
Tokens
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Commits
CommitProp
Michael Sartain
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%


static const struct file_operations tracing_saved_tgids_fops = {
	.open		= tracing_saved_tgids_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};



static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos)
{
	unsigned int *ptr = v;

	if (*pos || m->count)
		ptr++;

	(*pos)++;

	for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num];
	     ptr++) {
		if (*ptr == -1 || *ptr == NO_CMDLINE_MAP)
			continue;

		return ptr;
	}

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
62
72.94%
2
40.00%
Steven Rostedt
17
20.00%
2
40.00%
Avadh Patel
6
7.06%
1
20.00%
Total
85
100.00%
5
100.00%



static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos)
{
	void *v;
	loff_t l = 0;

	preempt_disable();
	arch_spin_lock(&trace_cmdline_lock);

	v = &savedcmd->map_cmdline_to_pid[0];
	while (l <= *pos) {
		v = saved_cmdlines_next(m, v, &l);
		if (!v)
			return NULL;
	}

	return v;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
59
77.63%
2
33.33%
Steven Rostedt
15
19.74%
3
50.00%
Avadh Patel
2
2.63%
1
16.67%
Total
76
100.00%
6
100.00%



static void saved_cmdlines_stop(struct seq_file *m, void *v)
{
	arch_spin_unlock(&trace_cmdline_lock);
	preempt_enable();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
24
100.00%
1
100.00%
Total
24
100.00%
1
100.00%



static int saved_cmdlines_show(struct seq_file *m, void *v)
{
	char buf[TASK_COMM_LEN];
	unsigned int *pid = v;

	__trace_find_cmdline(*pid, buf);
	seq_printf(m, "%d %s\n", *pid, buf);
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
51
100.00%
1
100.00%
Total
51
100.00%
1
100.00%


static const struct seq_operations tracing_saved_cmdlines_seq_ops = {
	.start		= saved_cmdlines_start,
	.next		= saved_cmdlines_next,
	.stop		= saved_cmdlines_stop,
	.show		= saved_cmdlines_show,
};



static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp)
{
	if (tracing_disabled)
		return -ENODEV;

	return seq_open(filp, &tracing_saved_cmdlines_seq_ops);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%


static const struct file_operations tracing_saved_cmdlines_fops = {
	.open		= tracing_saved_cmdlines_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};


static ssize_t

tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf,
				 size_t cnt, loff_t *ppos)
{
	char buf[64];
	int r;

	arch_spin_lock(&trace_cmdline_lock);
	r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num);
	arch_spin_unlock(&trace_cmdline_lock);

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
70
92.11%
1
50.00%
Namhyung Kim
6
7.89%
1
50.00%
Total
76
100.00%
2
100.00%



static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s)
{
	kfree(s->saved_cmdlines);
	kfree(s->map_cmdline_to_pid);
	kfree(s);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
30
100.00%
1
100.00%
Total
30
100.00%
1
100.00%



static int tracing_resize_saved_cmdlines(unsigned int val)
{
	struct saved_cmdlines_buffer *s, *savedcmd_temp;

	s = kmalloc(sizeof(*s), GFP_KERNEL);
	if (!s)
		return -ENOMEM;

	if (allocate_cmdlines_buffer(val, s) < 0) {
		kfree(s);
		return -ENOMEM;
	}

	arch_spin_lock(&trace_cmdline_lock);
	savedcmd_temp = savedcmd;
	savedcmd = s;
	arch_spin_unlock(&trace_cmdline_lock);
	free_saved_cmdlines_buffer(savedcmd_temp);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
77
85.56%
2
28.57%
Steven Rostedt
10
11.11%
3
42.86%
Namhyung Kim
2
2.22%
1
14.29%
Avadh Patel
1
1.11%
1
14.29%
Total
90
100.00%
7
100.00%


static ssize_t

tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf,
				  size_t cnt, loff_t *ppos)
{
	unsigned long val;
	int ret;

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	/* must have at least 1 entry or less than PID_MAX_DEFAULT */
	if (!val || val > PID_MAX_DEFAULT)
		return -EINVAL;

	ret = tracing_resize_saved_cmdlines((unsigned int)val);
	if (ret < 0)
		return ret;

	*ppos += cnt;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Yoshihiro Yunomae
85
90.43%
2
50.00%
Avadh Patel
5
5.32%
1
25.00%
Steven Rostedt
4
4.26%
1
25.00%
Total
94
100.00%
4
100.00%


static const struct file_operations tracing_saved_cmdlines_size_fops = {
	.open		= tracing_open_generic,
	.read		= tracing_saved_cmdlines_size_read,
	.write		= tracing_saved_cmdlines_size_write,
};

#ifdef CONFIG_TRACE_EVAL_MAP_FILE

static union trace_eval_map_item *

update_eval_map(union trace_eval_map_item *ptr)
{
	if (!ptr->map.eval_string) {
		if (ptr->tail.next) {
			ptr = ptr->tail.next;
			/* Set ptr to the next real item (skip head) */
			ptr++;
		} else
			return NULL;
	}
	return ptr;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
43
81.13%
3
33.33%
Jeremy Linton
4
7.55%
3
33.33%
Frédéric Weisbecker
2
3.77%
1
11.11%
Hiraku Toyooka
2
3.77%
1
11.11%
Eduard - Gabriel Munteanu
2
3.77%
1
11.11%
Total
53
100.00%
9
100.00%



static void *eval_map_next(struct seq_file *m, void *v, loff_t *pos)
{
	union trace_eval_map_item *ptr = v;

	/*
         * Paranoid! If ptr points to end, we don't want to increment past it.
         * This really should never happen.
         */
	ptr = update_eval_map(ptr);
	if (WARN_ON_ONCE(!ptr))
		return NULL;

	ptr++;

	(*pos)++;

	ptr = update_eval_map(ptr);

	return ptr;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
40
61.54%
4
40.00%
Arnaldo Carvalho de Melo
12
18.46%
1
10.00%
Frédéric Weisbecker
6
9.23%
1
10.00%
Jeremy Linton
4
6.15%
2
20.00%
Eduard - Gabriel Munteanu
2
3.08%
1
10.00%
Jens Axboe
1
1.54%
1
10.00%
Total
65
100.00%
10
100.00%



static void *eval_map_start(struct seq_file *m, loff_t *pos)
{
	union trace_eval_map_item *v;
	loff_t l = 0;

	mutex_lock(&trace_eval_mutex);

	v = trace_eval_maps;
	if (v)
		v++;

	while (v && l < *pos) {
		v = eval_map_next(m, v, &l);
	}

	return v;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
53
76.81%
1
12.50%
Vaibhav Nagarnaik
7
10.14%
1
12.50%
Jeremy Linton
5
7.25%
3
37.50%
Frédéric Weisbecker
2
2.90%
1
12.50%
Arnaldo Carvalho de Melo
1
1.45%
1
12.50%
Eduard - Gabriel Munteanu
1
1.45%
1
12.50%
Total
69
100.00%
8
100.00%



static void eval_map_stop(struct seq_file *m, void *v)
{
	mutex_unlock(&trace_eval_mutex);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
19
90.48%
1
33.33%
Jeremy Linton
2
9.52%
2
66.67%
Total
21
100.00%
3
100.00%



static int eval_map_show(struct seq_file *m, void *v)
{
	union trace_eval_map_item *ptr = v;

	seq_printf(m, "%s %ld (%s)\n",
		   ptr->map.eval_string, ptr->map.eval_value,
		   ptr->map.system);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
46
92.00%
1
25.00%
Jeremy Linton
4
8.00%
3
75.00%
Total
50
100.00%
4
100.00%


static const struct seq_operations tracing_eval_map_seq_ops = {
	.start		= eval_map_start,
	.next		= eval_map_next,
	.stop		= eval_map_stop,
	.show		= eval_map_show,
};



static int tracing_eval_map_open(struct inode *inode, struct file *filp)
{
	if (tracing_disabled)
		return -ENODEV;

	return seq_open(filp, &tracing_eval_map_seq_ops);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
31
93.94%
1
50.00%
Jeremy Linton
2
6.06%
1
50.00%
Total
33
100.00%
2
100.00%


static const struct file_operations tracing_eval_map_fops = {
	.open		= tracing_eval_map_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};


static inline union trace_eval_map_item *

trace_eval_jmp_to_tail(union trace_eval_map_item *ptr)
{
	/* Return tail of array given the head */
	return ptr + ptr->head.length + 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
23
88.46%
1
33.33%
Jeremy Linton
3
11.54%
2
66.67%
Total
26
100.00%
3
100.00%


static void

trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start,
			   int len)
{
	struct trace_eval_map **stop;
	struct trace_eval_map **map;
	union trace_eval_map_item *map_array;
	union trace_eval_map_item *ptr;

	stop = start + len;

	/*
         * The trace_eval_maps contains the map plus a head and tail item,
         * where the head holds the module and length of array, and the
         * tail holds a pointer to the next list.
         */
	map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL);
	if (!map_array) {
		pr_warn("Unable to allocate trace eval mapping\n");
		return;
	}

	mutex_lock(&trace_eval_mutex);

	if (!trace_eval_maps)
		trace_eval_maps = map_array;
	else {
		ptr = trace_eval_maps;
		for (;;) {
			ptr = trace_eval_jmp_to_tail(ptr);
			if (!ptr->tail.next)
				break;
			ptr = ptr->tail.next;

		}
		ptr->tail.next = map_array;
	}
	map_array->head.mod = mod;
	map_array->head.length = len;
	map_array++;

	for (map = start; (unsigned long)map < (unsigned long)stop; map++) {
		map_array->map = **map;
		map_array++;
	}
	memset(map_array, 0, sizeof(*map_array));

	mutex_unlock(&trace_eval_mutex);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
200
93.02%
1
14.29%
Jeremy Linton
14
6.51%
5
71.43%
Joe Perches
1
0.47%
1
14.29%
Total
215
100.00%
7
100.00%



static void trace_create_eval_file(struct dentry *d_tracer)
{
	trace_create_file("eval_map", 0444, d_tracer,
			  NULL, &tracing_eval_map_fops);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
22
88.00%
1
33.33%
Jeremy Linton
3
12.00%
2
66.67%
Total
25
100.00%
3
100.00%

#else /* CONFIG_TRACE_EVAL_MAP_FILE */


static inline void trace_create_eval_file(struct dentry *d_tracer) { }
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
10
90.91%
1
50.00%
Jeremy Linton
1
9.09%
1
50.00%
Total
11
100.00%
2
100.00%



static inline void trace_insert_eval_map_file(struct module *mod,
			      struct trace_eval_map **start, int len) { }
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
18
90.00%
1
33.33%
Jeremy Linton
2
10.00%
2
66.67%
Total
20
100.00%
3
100.00%

#endif /* !CONFIG_TRACE_EVAL_MAP_FILE */



static void trace_insert_eval_map(struct module *mod,
				  struct trace_eval_map **start, int len)
{
	struct trace_eval_map **map;

	if (len <= 0)
		return;

	map = start;

	trace_event_eval_update(map, len);

	trace_insert_eval_map_file(mod, start, len);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
48
90.57%
1
33.33%
Jeremy Linton
5
9.43%
2
66.67%
Total
53
100.00%
3
100.00%


static ssize_t

tracing_set_trace_read(struct file *filp, char __user *ubuf,
		       size_t cnt, loff_t *ppos)
{
	struct trace_array *tr = filp->private_data;
	char buf[MAX_TRACER_SIZE+2];
	int r;

	mutex_lock(&trace_types_lock);
	r = sprintf(buf, "%s\n", tr->current_trace->name);
	mutex_unlock(&trace_types_lock);

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
84
100.00%
1
100.00%
Total
84
100.00%
1
100.00%



int tracer_init(struct tracer *t, struct trace_array *tr)
{
	tracing_reset_online_cpus(&tr->trace_buffer);
	return t->init(tr);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
20
64.52%
2
40.00%
Arnaldo Carvalho de Melo
8
25.81%
1
20.00%
Frédéric Weisbecker
2
6.45%
1
20.00%
Eduard - Gabriel Munteanu
1
3.23%
1
20.00%
Total
31
100.00%
5
100.00%



static void set_buffer_entries(struct trace_buffer *buf, unsigned long val)
{
	int cpu;

	for_each_tracing_cpu(cpu)
		per_cpu_ptr(buf->data, cpu)->entries = val;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Vaibhav Nagarnaik
25
71.43%
1
25.00%
Eduard - Gabriel Munteanu
5
14.29%
1
25.00%
Steven Rostedt
5
14.29%
2
50.00%
Total
35
100.00%
4
100.00%

#ifdef CONFIG_TRACER_MAX_TRACE
/* resize @tr's buffer to the size of @size_tr's entries */


static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf,
					struct trace_buffer *size_buf, int cpu_id)
{
	int cpu, ret = 0;

	if (cpu_id == RING_BUFFER_ALL_CPUS) {
		for_each_tracing_cpu(cpu) {
			ret = ring_buffer_resize(trace_buf->buffer,
				 per_cpu_ptr(size_buf->data, cpu)->entries, cpu);
			if (ret < 0)
				break;
			per_cpu_ptr(trace_buf->data, cpu)->entries =
				per_cpu_ptr(size_buf->data, cpu)->entries;
		}
	} else {
		ret = ring_buffer_resize(trace_buf->buffer,
				 per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id);
		if (ret == 0)
			per_cpu_ptr(trace_buf->data, cpu_id)->entries =
				per_cpu_ptr(size_buf->data, cpu_id)->entries;
	}

	return ret;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Hiraku Toyooka
73
49.66%
1
12.50%
Eduard - Gabriel Munteanu
36
24.49%
1
12.50%
Steven Rostedt
25
17.01%
3
37.50%
Lai Jiangshan
6
4.08%
1
12.50%
Jens Axboe
6
4.08%
1
12.50%
Frédéric Weisbecker
1
0.68%
1
12.50%
Total
147
100.00%
8
100.00%

#endif /* CONFIG_TRACER_MAX_TRACE */



static int __tracing_resize_ring_buffer(struct trace_array *tr,
					unsigned long size, int cpu)
{
	int ret;

	/*
         * If kernel or user changes the size of the ring buffer
         * we use the size that was given, and we can forget about
         * expanding it later.
         */
	ring_buffer_expanded = true;

	/* May be called before buffers are initialized */
	if (!tr->trace_buffer.buffer)
		return 0;

	ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu);
	if (ret < 0)
		return ret;

#ifdef CONFIG_TRACER_MAX_TRACE
	if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) ||
	    !tr->current_trace->use_max_tr)
		goto out;

	ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu);
	if (ret < 0) {
		int r = resize_buffer_duplicate_size(&tr->trace_buffer,
						     &tr->trace_buffer, cpu);
		if (r < 0) {
			/*
                         * AARGH! We are left with different
                         * size max buffer!!!!
                         * The max buffer is our "snapshot" buffer.
                         * When a tracer needs a snapshot (one of the
                         * latency tracers), it swaps the max buffer
                         * with the saved snap shot. We succeeded to
                         * update the size of the main buffer, but failed to
                         * update the size of the max buffer. But when we tried
                         * to reset the main buffer to the original size, we
                         * failed there too. This is very unlikely to
                         * happen, but if it does, warn and kill all
                         * tracing.
                         */
			WARN_ON(1);
			tracing_disabled = 1;
		}
		return ret;
	}

	if (cpu == RING_BUFFER_ALL_CPUS)
		set_buffer_entries(&tr->max_buffer, size);
	else
		per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size;

 out:
#endif /* CONFIG_TRACER_MAX_TRACE */

	if (cpu == RING_BUFFER_ALL_CPUS)
		set_buffer_entries(&tr->trace_buffer, size);
	else
		per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size;

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
105
47.51%
8
61.54%
Vaibhav Nagarnaik
85
38.46%
2
15.38%
Eduard - Gabriel Munteanu
15
6.79%
1
7.69%
Motohiro Kosaki
14
6.33%
1
7.69%
Hiraku Toyooka
2
0.90%
1
7.69%
Total
221
100.00%
13
100.00%



static ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
					  unsigned long size, int cpu_id)
{
	int ret = size;

	mutex_lock(&trace_types_lock);

	if (cpu_id != RING_BUFFER_ALL_CPUS) {
		/* make sure, this cpu is enabled in the mask */
		if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) {
			ret = -EINVAL;
			goto out;
		}
	}

	ret = __tracing_resize_ring_buffer(tr, size, cpu_id);
	if (ret < 0)
		ret = -ENOMEM;

out:
	mutex_unlock(&trace_types_lock);

	return ret;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Vaibhav Nagarnaik
49
53.85%
2
20.00%
Steven Rostedt
30
32.97%
7
70.00%
Eduard - Gabriel Munteanu
12
13.19%
1
10.00%
Total
91
100.00%
10
100.00%

/**
 * tracing_update_buffers - used by tracing facility to expand ring buffers
 *
 * To save on memory when the tracing is never used on a system with it
 * configured in. The ring buffers are set to a minimum size. But once
 * a user starts to use the tracing facility, then they need to grow
 * to their default size.
 *
 * This function is to be called when a tracer is about to be used.
 */


int tracing_update_buffers(void)
{
	int ret = 0;

	mutex_lock(&trace_types_lock);
	if (!ring_buffer_expanded)
		ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size,
						RING_BUFFER_ALL_CPUS);
	mutex_unlock(&trace_types_lock);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Vaibhav Nagarnaik
31
70.45%
3
50.00%
Steven Rostedt
13
29.55%
3
50.00%
Total
44
100.00%
6
100.00%

struct trace_option_dentry;

static void
create_trace_option_files(struct trace_array *tr, struct tracer *tracer);

/*
 * Used to clear out the tracer before deletion of an instance.
 * Must have trace_types_lock held.
 */


static void tracing_set_nop(struct trace_array *tr)
{
	if (tr->current_trace == &nop_trace)
		return;
	
	tr->current_trace->enabled--;

	if (tr->current_trace->reset)
		tr->current_trace->reset(tr);

	tr->current_trace = &nop_trace;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
52
100.00%
2
100.00%
Total
52
100.00%
2
100.00%



static void add_tracer_options(struct trace_array *tr, struct tracer *t)
{
	/* Only enable if the directory has been created already. */
	if (!tr->dir)
		return;

	create_trace_option_files(tr, t);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
27
84.38%
3
75.00%
Pekka Paalanen
5
15.62%
1
25.00%
Total
32
100.00%
4
100.00%



static int tracing_set_tracer(struct trace_array *tr, const char *buf)
{
	struct tracer *t;
#ifdef CONFIG_TRACER_MAX_TRACE
	bool had_max_tr;
#endif
	int ret = 0;

	mutex_lock(&trace_types_lock);

	if (!ring_buffer_expanded) {
		ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
						RING_BUFFER_ALL_CPUS);
		if (ret < 0)
			goto out;
		ret = 0;
	}

	for (t = trace_types; t; t = t->next) {
		if (strcmp(t->name, buf) == 0)
			break;
	}
	if (!t) {
		ret = -EINVAL;
		goto out;
	}
	if (t == tr->current_trace)
		goto out;

	/* Some tracers won't work on kernel command line */
	if (system_state < SYSTEM_RUNNING && t->noboot) {
		pr_warn("Tracer '%s' is not allowed on command line, ignored\n",
			t->name);
		goto out;
	}

	/* Some tracers are only allowed for the top level buffer */
	if (!trace_ok_for_array(t, tr)) {
		ret = -EINVAL;
		goto out;
	}

	/* If trace pipe files are being read, we can't change the tracer */
	if (tr->current_trace->ref) {
		ret = -EBUSY;
		goto out;
	}

	trace_branch_disable();

	tr->current_trace->enabled--;

	if (tr->current_trace->reset)
		tr->current_trace->reset(tr);

	/* Current trace needs to be nop_trace before synchronize_sched */
	tr->current_trace = &nop_trace;

#ifdef CONFIG_TRACER_MAX_TRACE
	had_max_tr = tr->allocated_snapshot;

	if (had_max_tr && !t->use_max_tr) {
		/*
                 * We need to make sure that the update_max_tr sees that
                 * current_trace changed to nop_trace to keep it from
                 * swapping the buffers after we resize it.
                 * The update_max_tr is called from interrupts disabled
                 * so a synchronized_sched() is sufficient.
                 */
		synchronize_sched();
		free_snapshot(tr);
	}
#endif

#ifdef CONFIG_TRACER_MAX_TRACE
	if (t->use_max_tr && !had_max_tr) {
		ret = alloc_snapshot(tr);
		if (ret < 0)
			goto out;
	}
#endif

	if (t->init) {
		ret = tracer_init(t, tr);
		if (ret)
			goto out;
	}

	tr->current_trace = t;
	tr->current_trace->enabled++;
	trace_branch_enable(tr);
 out:
	mutex_unlock(&trace_types_lock);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
245
71.43%
18
58.06%
Ziqian SUN (Zamir)
25
7.29%
1
3.23%
Frédéric Weisbecker
21
6.12%
3
9.68%
Motohiro Kosaki
18
5.25%
1
3.23%
Pekka Paalanen
11
3.21%
1
3.23%
Mandeep Singh Baines
6
1.75%
1
3.23%
Anton Vorontsov
5
1.46%
1
3.23%
Peter Zijlstra
4
1.17%
1
3.23%
Vaibhav Nagarnaik
4
1.17%
2
6.45%
Arnaldo Carvalho de Melo
3
0.87%
1
3.23%
Hiraku Toyooka
1
0.29%
1
3.23%
Total
343
100.00%
31
100.00%


static ssize_t

tracing_set_trace_write(struct file *filp, const char __user *ubuf,
			size_t cnt, loff_t *ppos)
{
	struct trace_array *tr = filp->private_data;
	char buf[MAX_TRACER_SIZE+1];
	int i;
	size_t ret;
	int err;

	ret = cnt;

	if (cnt > MAX_TRACER_SIZE)
		cnt = MAX_TRACER_SIZE;

	if (copy_from_user(buf, ubuf, cnt))
		return -EFAULT;

	buf[cnt] = 0;

	/* strip ending whitespace. */
	for (i = cnt - 1; i > 0 && isspace(buf[i]); i--)
		buf[i] = 0;

	err = tracing_set_tracer(tr, buf);
	if (err)
		return err;

	*ppos += ret;

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Peter Zijlstra
88
62.41%
1
9.09%
Steven Rostedt
31
21.99%
5
45.45%
Frédéric Weisbecker
16
11.35%
2
18.18%
Li Zefan
3
2.13%
1
9.09%
Jiri Olsa
2
1.42%
1
9.09%
Pekka Paalanen
1
0.71%
1
9.09%
Total
141
100.00%
11
100.00%


static ssize_t

tracing_nsecs_read(unsigned long *ptr, char __user *ubuf,
		   size_t cnt, loff_t *ppos)
{
	char buf[64];
	int r;

	r = snprintf(buf, sizeof(buf), "%ld\n",
		     *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr));
	if (r > sizeof(buf))
		r = sizeof(buf);
	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
91
95.79%
2
66.67%
Stanislav Fomichev
4
4.21%
1
33.33%
Total
95
100.00%
3
100.00%


static ssize_t

tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf,
		    size_t cnt, loff_t *ppos)
{
	unsigned long val;
	int ret;

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	*ptr = val * 1000;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
54
87.10%
2
40.00%
Stanislav Fomichev
4
6.45%
1
20.00%
Peter Hüwe
3
4.84%
1
20.00%
Hannes Eder
1
1.61%
1
20.00%
Total
62
100.00%
5
100.00%


static ssize_t

tracing_thresh_read(struct file *filp, char __user *ubuf,
		    size_t cnt, loff_t *ppos)
{
	return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Stanislav Fomichev
36
100.00%
1
100.00%
Total
36
100.00%
1
100.00%


static ssize_t

tracing_thresh_write(struct file *filp, const char __user *ubuf,
		     size_t cnt, loff_t *ppos)
{
	struct trace_array *tr = filp->private_data;
	int ret;

	mutex_lock(&trace_types_lock);
	ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos);
	if (ret < 0)
		goto out;

	if (tr->current_trace->update_thresh) {
		ret = tr->current_trace->update_thresh(tr);
		if (ret < 0)
			goto out;
	}

	ret = cnt;
out:
	mutex_unlock(&trace_types_lock);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Stanislav Fomichev
110
100.00%
1
100.00%
Total
110
100.00%
1
100.00%

#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)


static ssize_t

tracing_max_lat_read(struct file *filp, char __user *ubuf,
		     size_t cnt, loff_t *ppos)
{
	return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Stanislav Fomichev
37
100.00%
1
100.00%
Total
37
100.00%
1
100.00%


static ssize_t

tracing_max_lat_write(struct file *filp, const char __user *ubuf,
		      size_t cnt, loff_t *ppos)
{
	return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Stanislav Fomichev
38
100.00%
1
100.00%
Total
38
100.00%
1
100.00%

#endif



static int tracing_open_pipe(struct inode *inode, struct file *filp)
{
	struct trace_array *tr = inode->i_private;
	struct trace_iterator *iter;
	int ret = 0;

	if (tracing_disabled)
		return -ENODEV;

	if (trace_array_get(tr) < 0)
		return -ENODEV;

	mutex_lock(&trace_types_lock);

	/* create a buffer to store the information to pass to userspace */
	iter = kzalloc(sizeof(*iter), GFP_KERNEL);
	if (!iter) {
		ret = -ENOMEM;
		__trace_array_put(tr);
		goto out;
	}

	trace_seq_init(&iter->seq);
	iter->trace = tr->current_trace;

	if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) {
		ret = -ENOMEM;
		goto fail;
	}

	/* trace pipe does not show start of buffer */
	cpumask_setall(iter->started);

	if (tr->trace_flags & TRACE_ITER_LATENCY_FMT)
		iter->iter_flags |= TRACE_FILE_LAT_FMT;

	/* Output in nanoseconds only if we are using a clock in nanoseconds. */
	if (trace_clocks[tr->clock_id].in_ns)
		iter->iter_flags |= TRACE_FILE_TIME_IN_NS;

	iter->tr = tr;
	iter->trace_buffer = &tr->trace_buffer;
	iter->cpu_file = tracing_get_cpu(inode);
	mutex_init(&iter->mutex);
	filp->private_data = iter;

	if (iter->trace->pipe_open)
		iter->trace->pipe_open(iter);

	nonseekable_open(inode, filp);

	tr->current_trace->ref++;
out:
	mutex_unlock(&trace_types_lock);
	return ret;

fail:
	kfree(iter->trace);
	kfree(iter);
	__trace_array_put(tr);
	mutex_unlock(&trace_types_lock);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
160
56.54%
11
55.00%
Frédéric Weisbecker
62
21.91%
2
10.00%
Rusty Russell
17
6.01%
1
5.00%
David Sharp
15
5.30%
1
5.00%
Oleg Nesterov
11
3.89%
1
5.00%
Arnd Bergmann
7
2.47%
1
5.00%
Alexander Z Lam
5
1.77%
1
5.00%
Thomas Gleixner
3
1.06%
1
5.00%
Yoshihiro Yunomae
3
1.06%
1
5.00%
Total
283
100.00%
20
100.00%



static int tracing_release_pipe(struct inode *inode, struct file *file)
{
	struct trace_iterator *iter = file->private_data;
	struct trace_array *tr = inode->i_private;

	mutex_lock(&trace_types_lock);

	tr->current_trace->ref--;

	if (iter->trace->pipe_close)
		iter->trace->pipe_close(iter);

	mutex_unlock(&trace_types_lock);

	free_cpumask_var(iter->started);
	mutex_destroy(&iter->mutex);
	kfree(iter);

	trace_array_put(tr);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
64
65.31%
5
55.56%
Frédéric Weisbecker
29
29.59%
2
22.22%
Rusty Russell
3
3.06%
1
11.11%
Oleg Nesterov
2
2.04%
1
11.11%
Total
98
100.00%
9
100.00%


static unsigned int

trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table)
{
	struct trace_array *tr = iter->tr;

	/* Iterators are static, they should be filled or empty */
	if (trace_buffer_iter(iter, iter->cpu_file))
		return POLLIN | POLLRDNORM;

	if (tr->trace_flags & TRACE_ITER_BLOCK)
		/*
                 * Always select as readable when in blocking mode
                 */
		return POLLIN | POLLRDNORM;
	else
		return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file,
					     filp, poll_table);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
43
53.75%
4
80.00%
Soeren Sandmann Pedersen
37
46.25%
1
20.00%
Total
80
100.00%
5
100.00%


static unsigned int

tracing_poll_pipe(struct file *filp, poll_table *poll_table)
{
	struct trace_iterator *iter = filp->private_data;

	return trace_poll(iter, filp, poll_table);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
35
100.00%
1
100.00%
Total
35
100.00%
1
100.00%

/* Must be called with iter->mutex held. */


static int tracing_wait_pipe(struct file *filp)
{
	struct trace_iterator *iter = filp->private_data;
	int ret;

	while (trace_empty(iter)) {

		if ((filp->f_flags & O_NONBLOCK)) {
			return -EAGAIN;
		}

		/*
                 * We block until we read something and tracing is disabled.
                 * We still block if tracing is disabled, but we have never
                 * read anything. This allows a user to cat this file, and
                 * then enable tracing. But after we have read something,
                 * we give an EOF when tracing is again disabled.
                 *
                 * iter->pos will be 0 if we haven't read anything.
                 */
		if (!tracer_tracing_is_on(iter->tr) && iter->pos)
			break;

		mutex_unlock(&iter->mutex);

		ret = wait_on_pipe(iter, false);

		mutex_lock(&iter->mutex);

		if (ret)
			return ret;
	}

	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Eduard - Gabriel Munteanu
63
63.64%
1
12.50%
Steven Rostedt
21
21.21%
3
37.50%
Frédéric Weisbecker
7
7.07%
2
25.00%
Tahsin Erdogan
6
6.06%
1
12.50%
Rabin Vincent
2
2.02%
1
12.50%
Total
99
100.00%
8
100.00%

/*
 * Consumer reader.
 */

static ssize_t

tracing_read_pipe(struct file *filp, char __user *ubuf,
		  size_t cnt, loff_t *ppos)
{
	struct trace_iterator *iter = filp->private_data;
	ssize_t sret;

	/*
         * Avoid more than one consumer on a single file descriptor
         * This is just a matter of traces coherency, the ring buffer itself
         * is protected.
         */
	mutex_lock(&iter->mutex);

	/* return any leftover data */
	sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
	if (sret != -EBUSY)
		goto out;

	trace_seq_init(&iter->seq);

	if (iter->trace->read) {
		sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
		if (sret)
			goto out;
	}

waitagain:
	sret = tracing_wait_pipe(filp);
	if (sret <= 0)
		goto out;

	/* stop when tracing is finished */
	if (trace_empty(iter)) {
		sret = 0;
		goto out;
	}

	if (cnt >= PAGE_SIZE)
		cnt = PAGE_SIZE - 1;

	/* reset all but tr, trace, and overruns */
	memset(&iter->seq, 0,
	       sizeof(struct trace_iterator) -
	       offsetof(struct trace_iterator, seq));
	cpumask_clear(iter->started);
	iter->pos = -1;

	trace_event_read_lock();
	trace_access_lock(iter->cpu_file);
	while (trace_find_next_entry_inc(iter) != NULL) {
		enum print_line_t ret;
		int save_len = iter->seq.seq.len;

		ret = print_trace_line(iter);
		if (ret == TRACE_TYPE_PARTIAL_LINE) {
			/* don't print partial lines */
			iter->seq.seq.len = save_len;
			break;
		}
		if (ret != TRACE_TYPE_NO_CONSUME)
			trace_consume(iter);

		if (trace_seq_used(&iter->seq) >= cnt)
			break;

		/*
                 * Setting the full flag means we reached the trace_seq buffer
                 * size and we should leave by partial output condition above.
                 * One of the trace_seq_* functions is not used properly.
                 */
		WARN_ONCE(iter->seq.full, "full flag set for trace type %d",
			  iter->ent->type);
	}
	trace_access_unlock(iter->cpu_file);
	trace_event_read_unlock();

	/* Now copy what we have to the user */
	sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
	if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq))
		trace_seq_init(&iter->seq);

	/*
         * If there was nothing to send to user, in spite of consuming trace
         * entries, go back to wait for more entries.
         */
	if (sret == -EBUSY)
		goto waitagain;

out:
	mutex_unlock(&iter->mutex);

	return sret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
265
69.92%
12
48.00%
Pekka Paalanen
42
11.08%
2
8.00%
Lai Jiangshan
20
5.28%
2
8.00%
Jiri Olsa
18
4.75%
1
4.00%
Frédéric Weisbecker
15
3.96%
3
12.00%
Eduard - Gabriel Munteanu
9
2.37%
1
4.00%
Andrey Vagin
7
1.85%
1
4.00%
Ingo Molnar
1
0.26%
1
4.00%
Jason Wessel
1
0.26%
1
4.00%
Lucas De Marchi
1
0.26%
1
4.00%
Total
379
100.00%
25
100.00%



static void tracing_spd_release_pipe(struct splice_pipe_desc *spd,
				     unsigned int idx)
{
	__free_page(spd->pages[idx]);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Eduard - Gabriel Munteanu
22
88.00%
1
50.00%
Steven Rostedt
3
12.00%
1
50.00%
Total
25
100.00%
2
100.00%


static const struct pipe_buf_operations tracing_pipe_buf_ops = {
	.can_merge		= 0,
	.confirm		= generic_pipe_buf_confirm,
	.release		= generic_pipe_buf_release,
	.steal			= generic_pipe_buf_steal,
	.get			= generic_pipe_buf_get,
};


static size_t

tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
{
	size_t count;
	int save_len;
	int ret;

	/* Seq buffer is page-sized, exactly what we need. */
	for (;;) {
		save_len = iter->seq.seq.len;
		ret = print_trace_line(iter);

		if (trace_seq_has_overflowed(&iter->seq)) {
			iter->seq.seq.len = save_len;
			break;
		}

		/*
                 * This should not be hit, because it should only
                 * be set if the iter->seq overflowed. But check it
                 * anyway to be safe.
                 */
		if (ret == TRACE_TYPE_PARTIAL_LINE) {
			iter->seq.seq.len = save_len;
			break;
		}

		count = trace_seq_used(&iter->seq) - save_len;
		if (rem < count) {
			rem = 0;
			iter->seq.seq.len = save_len;
			break;
		}

		if (ret != TRACE_TYPE_NO_CONSUME)
			trace_consume(iter);
		rem -= count;
		if (!trace_find_next_entry_inc(iter))	{
			rem = 0;
			iter->ent = NULL;
			break;
		}
	}

	return rem;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
158
95.76%
4
66.67%
Lai Jiangshan
6
3.64%
1
16.67%
Jason Wessel
1
0.61%
1
16.67%
Total
165
100.00%
6
100.00%



static ssize_t tracing_splice_read_pipe(struct file *filp,
					loff_t *ppos,
					struct pipe_inode_info *pipe,
					size_t len,
					unsigned int flags)
{
	struct page *pages_def[PIPE_DEF_BUFFERS];
	struct partial_page partial_def[PIPE_DEF_BUFFERS];
	struct trace_iterator *iter = filp->private_data;
	struct splice_pipe_desc spd = {
		.pages		= pages_def,
		.partial	= partial_def,
		.nr_pages	= 0, /* This gets updated below. */
		.nr_pages_max	= PIPE_DEF_BUFFERS,
		.ops		= &tracing_pipe_buf_ops,
		.spd_release	= tracing_spd_release_pipe,
        };
	ssize_t ret;
	size_t rem;
	unsigned int i;

	if (splice_grow_spd(pipe, &spd))
		return -ENOMEM;

	mutex_lock(&iter->mutex);

	if (iter->trace->splice_read) {
		ret = iter->trace->splice_read(iter, filp,
					       ppos, pipe, len, flags);
		if (ret)
			goto out_err;
	}

	ret = tracing_wait_pipe(filp);
	if (ret <= 0)
		goto out_err;

	if (!iter->ent && !trace_find_next_entry_inc(iter)) {
		ret = -EFAULT;
		goto out_err;
	}

	trace_event_read_lock();
	trace_access_lock(iter->cpu_file);

	/* Fill as many pages as possible. */
	for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) {
		spd.pages[i] = alloc_page(GFP_KERNEL);
		if (!spd.pages[i])
			break;

		rem = tracing_fill_pipe_page(rem, iter);

		/* Copy the data into the page, so we can start over. */
		ret = trace_seq_to_buffer(&iter->seq,
					  page_address(spd.pages[i]),
					  trace_seq_used(&iter->seq));
		if (ret < 0) {
			__free_page(spd.pages[i]);
			break;
		}
		spd.partial[i].offset = 0;
		spd.partial[i].len = trace_seq_used(&iter->seq);

		trace_seq_init(&iter->seq);
	}

	trace_access_unlock(iter->cpu_file);
	trace_event_read_unlock();
	mutex_unlock(&iter->mutex);

	spd.nr_pages = i;

	if (i)
		ret = splice_to_pipe(pipe, &spd);
	else
		ret = 0;
out:
	splice_shrink_spd(&spd);
	return ret;

out_err:
	mutex_unlock(&iter->mutex);
	goto out;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Eduard - Gabriel Munteanu
273
65.78%
1
6.67%
Steven Rostedt
49
11.81%
7
46.67%
Jens Axboe
48
11.57%
1
6.67%
Lai Jiangshan
20
4.82%
2
13.33%
Frédéric Weisbecker
16
3.86%
1
6.67%
Eric Dumazet
5
1.20%
1
6.67%
Al Viro
3
0.72%
1
6.67%
Jason Wessel
1
0.24%
1
6.67%
Total
415
100.00%
15
100.00%


static ssize_t

tracing_entries_read(struct file *filp, char __user *ubuf,
		     size_t cnt, loff_t *ppos)
{
	struct inode *inode = file_inode(filp);
	struct trace_array *tr = inode->i_private;
	int cpu = tracing_get_cpu(inode);
	char buf[64];
	int r = 0;
	ssize_t ret;

	mutex_lock(&trace_types_lock);

	if (cpu == RING_BUFFER_ALL_CPUS) {
		int cpu, buf_size_same;
		unsigned long size;

		size = 0;
		buf_size_same = 1;
		/* check if all cpu sizes are same */
		for_each_tracing_cpu(cpu) {
			/* fill in the size from first enabled cpu */
			if (size == 0)
				size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries;
			if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) {
				buf_size_same = 0;
				break;
			}
		}

		if (buf_size_same) {
			if (!ring_buffer_expanded)
				r = sprintf(buf, "%lu (expanded: %lu)\n",
					    size >> 10,
					    trace_buf_size >> 10);
			else
				r = sprintf(buf, "%lu\n", size >> 10);
		} else
			r = sprintf(buf, "X\n");
	} else
		r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10);

	mutex_unlock(&trace_types_lock);

	ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Vaibhav Nagarnaik
106
42.57%
1
14.29%
Steven Rostedt
90
36.14%
4
57.14%
Eduard - Gabriel Munteanu
38
15.26%
1
14.29%
Oleg Nesterov
15
6.02%
1
14.29%
Total
249
100.00%
7
100.00%


static ssize_t

tracing_entries_write(struct file *filp, const char __user *ubuf,
		      size_t cnt, loff_t *ppos)
{
	struct inode *inode = file_inode(filp);
	struct trace_array *tr = inode->i_private;
	unsigned long val;
	int ret;

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	/* must have at least 1 entry */
	if (!val)
		return -EINVAL;

	/* value is in KB */
	val <<= 10;
	ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode));
	if (ret < 0)
		return ret;

	*ppos += cnt;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
53
45.30%
9
60.00%
Eduard - Gabriel Munteanu
30
25.64%
1
6.67%
Oleg Nesterov
17
14.53%
1
6.67%
Vaibhav Nagarnaik
12
10.26%
2
13.33%
Peter Hüwe
3
2.56%
1
6.67%
Jiri Olsa
2
1.71%
1
6.67%
Total
117
100.00%
15
100.00%


static ssize_t

tracing_total_entries_read(struct file *filp, char __user *ubuf,
				size_t cnt, loff_t *ppos)
{
	struct trace_array *tr = filp->private_data;
	char buf[64];
	int r, cpu;
	unsigned long size = 0, expanded_size = 0;

	mutex_lock(&trace_types_lock);
	for_each_tracing_cpu(cpu) {
		size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10;
		if (!ring_buffer_expanded)
			expanded_size += trace_buf_size >> 10;
	}
	if (ring_buffer_expanded)
		r = sprintf(buf, "%lu\n", size);
	else
		r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size);
	mutex_unlock(&trace_types_lock);

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Vaibhav Nagarnaik
136
95.77%
3
60.00%
Steven Rostedt
6
4.23%
2
40.00%
Total
142
100.00%
5
100.00%


static ssize_t

tracing_free_buffer_write(struct file *filp, const char __user *ubuf,
			  size_t cnt, loff_t *ppos)
{
	/*
         * There is no need to read what the user has written, this function
         * is just to make sure that there is no error when "echo" is used
         */

	*ppos += cnt;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Vaibhav Nagarnaik
30
90.91%
2
66.67%
Steven Rostedt
3
9.09%
1
33.33%
Total
33
100.00%
3
100.00%


static int

tracing_free_buffer_release(struct inode *inode, struct file *filp)
{
	struct trace_array *tr = inode->i_private;

	/* disable tracing ? */
	if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE)
		tracer_tracing_off(tr);
	/* resize the ring buffer to 0 */
	tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS);

	trace_array_put(tr);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
30
52.63%
6
66.67%
Vaibhav Nagarnaik
23
40.35%
2
22.22%
Alexander Z Lam
4
7.02%
1
11.11%
Total
57
100.00%
9
100.00%


static ssize_t

tracing_mark_write(struct file *filp, const char __user *ubuf,
					size_t cnt, loff_t *fpos)
{
	struct trace_array *tr = filp->private_data;
	struct ring_buffer_event *event;
	struct ring_buffer *buffer;
	struct print_entry *entry;
	unsigned long irq_flags;
	const char faulted[] = "<faulted>";
	ssize_t written;
	int size;
	int len;

/* Used in tracing_mark_raw_write() as well */

#define FAULTED_SIZE (sizeof(faulted) - 1) /* '\0' is already accounted for */

	if (tracing_disabled)
		return -EINVAL;

	if (!(tr->trace_flags & TRACE_ITER_MARKERS))
		return -EINVAL;

	if (cnt > TRACE_BUF_SIZE)
		cnt = TRACE_BUF_SIZE;

	BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);

	local_save_flags(irq_flags);
	size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */

	/* If less than "<faulted>", then make sure we can still add that */
	if (cnt < FAULTED_SIZE)
		size += FAULTED_SIZE - cnt;

	buffer = tr->trace_buffer.buffer;
	event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
					    irq_flags, preempt_count());
	if (unlikely(!event))
		/* Ring buffer disabled, return as if not open for write */
		return -EBADF;

	entry = ring_buffer_event_data(event);
	entry->ip = _THIS_IP_;

	len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt);
	if (len) {
		memcpy(&entry->buf, faulted, FAULTED_SIZE);
		cnt = FAULTED_SIZE;
		written = -EFAULT;
	} else
		written = cnt;
	len = cnt;

	if (entry->buf[cnt - 1] != '\n') {
		entry->buf[cnt] = '\n';
		entry->buf[cnt + 1] = '\0';
	} else
		entry->buf[cnt] = '\0';

	__buffer_unlock_commit(buffer, event);

	if (written > 0)
		*fpos += written;

	return written;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
208
66.88%
11
61.11%
Vaibhav Nagarnaik
67
21.54%
3
16.67%
Pekka Paalanen
20
6.43%
1
5.56%
Mandeep Singh Baines
12
3.86%
1
5.56%
Marcin Ślusarz
3
0.96%
1
5.56%
Alexander Z Lam
1
0.32%
1
5.56%
Total
311
100.00%
18
100.00%

/* Limit it for now to 3K (including tag) */

#define RAW_DATA_MAX_SIZE (1024*3)


static ssize_t

tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
					size_t cnt, loff_t *fpos)
{
	struct trace_array *tr = filp->private_data;
	struct ring_buffer_event *event;
	struct ring_buffer *buffer;
	struct raw_data_entry *entry;
	const char faulted[] = "<faulted>";
	unsigned long irq_flags;
	ssize_t written;
	int size;
	int len;


#define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int))

	if (tracing_disabled)
		return -EINVAL;

	if (!(tr->trace_flags & TRACE_ITER_MARKERS))
		return -EINVAL;

	/* The marker must at least have a tag id */
	if (cnt < sizeof(unsigned int) || cnt > RAW_DATA_MAX_SIZE)
		return -EINVAL;

	if (cnt > TRACE_BUF_SIZE)
		cnt = TRACE_BUF_SIZE;

	BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);

	local_save_flags(irq_flags);
	size = sizeof(*entry) + cnt;
	if (cnt < FAULT_SIZE_ID)
		size += FAULT_SIZE_ID - cnt;

	buffer = tr->trace_buffer.buffer;
	event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size,
					    irq_flags, preempt_count());
	if (!event)
		/* Ring buffer disabled, return as if not open for write */
		return -EBADF;

	entry = ring_buffer_event_data(event);

	len = __copy_from_user_inatomic(&entry->id, ubuf, cnt);
	if (len) {
		entry->id = -1;
		memcpy(&entry->buf, faulted, FAULTED_SIZE);
		written = -EFAULT;
	} else
		written = cnt;

	__buffer_unlock_commit(buffer, event);

	if (written > 0)
		*fpos += written;

	return written;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
176
65.43%
7
58.33%
Pekka Paalanen
60
22.30%
1
8.33%
Mandeep Singh Baines
13
4.83%
1
8.33%
Alexander Z Lam
11
4.09%
1
8.33%
Marcin Ślusarz
6
2.23%
1
8.33%
Carsten Emde
3
1.12%
1
8.33%
Total
269
100.00%
12
100.00%



static int tracing_clock_show(struct seq_file *m, void *v)
{
	struct trace_array *tr = m->private;
	int i;

	for (i = 0; i < ARRAY_SIZE(trace_clocks); i++)
		seq_printf(m,
			"%s%s%s%s", i ? " " : "",
			i == tr->clock_id ? "[" : "", trace_clocks[i].name,
			i == tr->clock_id ? "]" : "");
	seq_putc(m, '\n');

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Zhao Lei
66
70.97%
1
33.33%
Steven Rostedt
15
16.13%
1
33.33%
Li Zefan
12
12.90%
1
33.33%
Total
93
100.00%
3
100.00%



static int tracing_set_clock(struct trace_array *tr, const char *clockstr)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) {
		if (strcmp(trace_clocks[i].name, clockstr) == 0)
			break;
	}
	if (i == ARRAY_SIZE(trace_clocks))
		return -EINVAL;

	mutex_lock(&trace_types_lock);

	tr->clock_id = i;

	ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func);

	/*
         * New clock may not be consistent with the previous clock.
         * Reset the buffer so that it doesn't have incomparable timestamps.
         */
	tracing_reset_online_cpus(&tr->trace_buffer);

#ifdef CONFIG_TRACER_MAX_TRACE
	if (tr->max_buffer.buffer)
		ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func);
	tracing_reset_online_cpus(&tr->max_buffer);
#endif

	mutex_unlock(&trace_types_lock);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Zhao Lei
100
66.67%
1
16.67%
Steven Rostedt
41
27.33%
3
50.00%
David Sharp
5
3.33%
1
16.67%
Alexander Z Lam
4
2.67%
1
16.67%
Total
150
100.00%
6
100.00%



static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
				   size_t cnt, loff_t *fpos)
{
	struct seq_file *m = filp->private_data;
	struct trace_array *tr = m->private;
	char buf[64];
	const char *clockstr;
	int ret;

	if (cnt >= sizeof(buf))
		return -EINVAL;

	if (copy_from_user(buf, ubuf, cnt))
		return -EFAULT;

	buf[cnt] = 0;

	clockstr = strstrip(buf);

	ret = tracing_set_clock(tr, clockstr);
	if (ret)
		return ret;

	*fpos += cnt;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
113
92.62%
1
50.00%
Zhao Lei
9
7.38%
1
50.00%
Total
122
100.00%
2
100.00%



static int tracing_clock_open(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;
	int ret;

	if (tracing_disabled)
		return -ENODEV;

	if (trace_array_get(tr))
		return -ENODEV;

	ret = single_open(file, tracing_clock_show, inode->i_private);
	if (ret < 0)
		trace_array_put(tr);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
41
55.41%
2
66.67%
Li Zefan
33
44.59%
1
33.33%
Total
74
100.00%
3
100.00%


struct ftrace_buffer_info {
	
struct trace_iterator	iter;
	
void			*spare;
	
unsigned int		spare_cpu;
	
unsigned int		read;
};

#ifdef CONFIG_TRACER_SNAPSHOT


static int tracing_snapshot_open(struct inode *inode, struct file *file)
{
	struct trace_array *tr = inode->i_private;
	struct trace_iterator *iter;
	struct seq_file *m;
	int ret = 0;

	if (trace_array_get(tr) < 0)
		return -ENODEV;

	if (file->f_mode & FMODE_READ) {
		iter = __tracing_open(inode, file, true);
		if (IS_ERR(iter))
			ret = PTR_ERR(iter);
	} else {
		/* Writes still need the seq_file to hold the private data */
		ret = -ENOMEM;
		m = kzalloc(sizeof(*m), GFP_KERNEL);
		if (!m)
			goto out;
		iter = kzalloc(sizeof(*iter), GFP_KERNEL);
		if (!iter) {
			kfree(m);
			goto out;
		}
		ret = 0;

		iter->tr = tr;
		iter->trace_buffer = &tr->max_buffer;
		iter->cpu_file = tracing_get_cpu(inode);
		m->private = iter;
		file->private_data = m;
	}
out:
	if (ret < 0)
		trace_array_put(tr);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
124
61.39%
5
55.56%
Hiraku Toyooka
54
26.73%
1
11.11%
Alexander Z Lam
17
8.42%
1
11.11%
Oleg Nesterov
6
2.97%
1
11.11%
Arnd Bergmann
1
0.50%
1
11.11%
Total
202
100.00%
9
100.00%


static ssize_t

tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
		       loff_t *ppos)
{
	struct seq_file *m = filp->private_data;
	struct trace_iterator *iter = m->private;
	struct trace_array *tr = iter->tr;
	unsigned long val;
	int ret;

	ret = tracing_update_buffers();
	if (ret < 0)
		return ret;

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	mutex_lock(&trace_types_lock);

	if (tr->current_trace->use_max_tr) {
		ret = -EBUSY;
		goto out;
	}

	switch (val) {
	case 0:
		if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
			ret = -EINVAL;
			break;
		}
		if (tr->allocated_snapshot)
			free_snapshot(tr);
		break;
	case 1:
/* Only allow per-cpu swap if the ring buffer supports it */
#ifndef CONFIG_RING_BUFFER_ALLOW_SWAP
		if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
			ret = -EINVAL;
			break;
		}
#endif
		if (!tr->allocated_snapshot) {
			ret = alloc_snapshot(tr);
			if (ret < 0)
				break;
		}
		local_irq_disable();
		/* Now, we're going to swap */
		if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
			update_max_tr(tr, current, smp_processor_id());
		else
			update_max_tr_single(tr, current, iter->cpu_file);
		local_irq_enable();
		break;
	default:
		if (tr->allocated_snapshot) {
			if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
				tracing_reset_online_cpus(&tr->max_buffer);
			else
				tracing_reset(&tr->max_buffer, iter->cpu_file);
		}
		break;
	}

	if (ret >= 0) {
		*ppos += cnt;
		ret = cnt;
	}
out:
	mutex_unlock(&trace_types_lock);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Hiraku Toyooka
173
56.35%
1
16.67%
Steven Rostedt
134
43.65%
5
83.33%
Total
307
100.00%
6
100.00%



static int tracing_snapshot_release(struct inode *inode, struct file *file)
{
	struct seq_file *m = file->private_data;
	int ret;

	ret = tracing_release(inode, file);

	if (file->f_mode & FMODE_READ)
		return ret;

	/* If write only, the seq_file is just a stub */
	if (m)
		kfree(m->private);
	kfree(m);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
68
100.00%
2
100.00%
Total
68
100.00%
2
100.00%

static int tracing_buffers_open(struct inode *inode, struct file *filp);
static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf,
				    size_t count, loff_t *ppos);
static int tracing_buffers_release(struct inode *inode, struct file *file);
static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos,
		   struct pipe_inode_info *pipe, size_t len, unsigned int flags);



static int snapshot_raw_open(struct inode *inode, struct file *filp)
{
	struct ftrace_buffer_info *info;
	int ret;

	ret = tracing_buffers_open(inode, filp);
	if (ret < 0)
		return ret;

	info = filp->private_data;

	if (info->iter.trace->use_max_tr) {
		tracing_buffers_release(inode, filp);
		return -EBUSY;
	}

	info->iter.snapshot = true;
	info->iter.trace_buffer = &info->iter.tr->max_buffer;

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
97
100.00%
1
100.00%
Total
97
100.00%
1
100.00%

#endif /* CONFIG_TRACER_SNAPSHOT */



static const struct file_operations tracing_thresh_fops = {
	.open		= tracing_open_generic,
	.read		= tracing_thresh_read,
	.write		= tracing_thresh_write,
	.llseek		= generic_file_llseek,
};

#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)

static const struct file_operations tracing_max_lat_fops = {
	.open		= tracing_open_generic,
	.read		= tracing_max_lat_read,
	.write		= tracing_max_lat_write,
	.llseek		= generic_file_llseek,
};
#endif


static const struct file_operations set_tracer_fops = {
	.open		= tracing_open_generic,
	.read		= tracing_set_trace_read,
	.write		= tracing_set_trace_write,
	.llseek		= generic_file_llseek,
};


static const struct file_operations tracing_pipe_fops = {
	.open		= tracing_open_pipe,
	.poll		= tracing_poll_pipe,
	.read		= tracing_read_pipe,
	.splice_read	= tracing_splice_read_pipe,
	.release	= tracing_release_pipe,
	.llseek		= no_llseek,
};


static const struct file_operations tracing_entries_fops = {
	.open		= tracing_open_generic_tr,
	.read		= tracing_entries_read,
	.write		= tracing_entries_write,
	.llseek		= generic_file_llseek,
	.release	= tracing_release_generic_tr,
};


static const struct file_operations tracing_total_entries_fops = {
	.open		= tracing_open_generic_tr,
	.read		= tracing_total_entries_read,
	.llseek		= generic_file_llseek,
	.release	= tracing_release_generic_tr,
};


static const struct file_operations tracing_free_buffer_fops = {
	.open		= tracing_open_generic_tr,
	.write		= tracing_free_buffer_write,
	.release	= tracing_free_buffer_release,
};


static const struct file_operations tracing_mark_fops = {
	.open		= tracing_open_generic_tr,
	.write		= tracing_mark_write,
	.llseek		= generic_file_llseek,
	.release	= tracing_release_generic_tr,
};


static const struct file_operations tracing_mark_raw_fops = {
	.open		= tracing_open_generic_tr,
	.write		= tracing_mark_raw_write,
	.llseek		= generic_file_llseek,
	.release	= tracing_release_generic_tr,
};


static const struct file_operations trace_clock_fops = {
	.open		= tracing_clock_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= tracing_single_release_tr,
	.write		= tracing_clock_write,
};

#ifdef CONFIG_TRACER_SNAPSHOT

static const struct file_operations snapshot_fops = {
	.open		= tracing_snapshot_open,
	.read		= seq_read,
	.write		= tracing_snapshot_write,
	.llseek		= tracing_lseek,
	.release	= tracing_snapshot_release,
};


static const struct file_operations snapshot_raw_fops = {
	.open		= snapshot_raw_open,
	.read		= tracing_buffers_read,
	.release	= tracing_buffers_release,
	.splice_read	= tracing_buffers_splice_read,
	.llseek		= no_llseek,
};

#endif /* CONFIG_TRACER_SNAPSHOT */



static int tracing_buffers_open(struct inode *inode, struct file *filp)
{
	struct trace_array *tr = inode->i_private;
	struct ftrace_buffer_info *info;
	int ret;

	if (tracing_disabled)
		return -ENODEV;

	if (trace_array_get(tr) < 0)
		return -ENODEV;

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
		trace_array_put(tr);
		return -ENOMEM;
	}

	mutex_lock(&trace_types_lock);

	info->iter.tr		= tr;
	info->iter.cpu_file	= tracing_get_cpu(inode);
	info->iter.trace	= tr->current_trace;
	info->iter.trace_buffer = &tr->trace_buffer;
	info->spare		= NULL;
	/* Force reading ring buffer for first read */
	info->read		= (unsigned int)-1;

	filp->private_data = info;

	tr->current_trace->ref++;

	mutex_unlock(&trace_types_lock);

	ret = nonseekable_open(inode, filp);
	if (ret < 0)
		trace_array_put(tr);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
167
88.36%
11
64.71%
Pekka Paalanen
9
4.76%
1
5.88%
Oleg Nesterov
6
3.17%
1
5.88%
Lai Jiangshan
5
2.65%
2
11.76%
Carsten Emde
1
0.53%
1
5.88%
Marcin Ślusarz
1
0.53%
1
5.88%
Total
189
100.00%
17
100.00%


static unsigned int

tracing_buffers_poll(struct file *filp, poll_table *poll_table)
{
	struct ftrace_buffer_info *info = filp->private_data;
	struct trace_iterator *iter = &info->iter;

	return trace_poll(iter, filp, poll_table);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
42
93.33%
2
66.67%
Pekka Paalanen
3
6.67%
1
33.33%
Total
45
100.00%
3
100.00%


static ssize_t

tracing_buffers_read(struct file *filp, char __user *ubuf,
		     size_t count, loff_t *ppos)
{
	struct ftrace_buffer_info *info = filp->private_data;
	struct trace_iterator *iter = &info->iter;
	ssize_t ret = 0;
	ssize_t size;

	if (!count)
		return 0;

#ifdef CONFIG_TRACER_MAX_TRACE
	if (iter->snapshot && iter->tr->current_trace->use_max_tr)
		return -EBUSY;
#endif

	if (!info->spare) {
		info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer,
							  iter->cpu_file);
		if (IS_ERR(info->spare)) {
			ret = PTR_ERR(info->spare);
			info->spare = NULL;
		} else {
			info->spare_cpu = iter->cpu_file;
		}
	}
	if (!info->spare)
		return ret;

	/* Do we have previous read data to read? */
	if (info->read < PAGE_SIZE)
		goto read;

 again:
	trace_access_lock(iter->cpu_file);
	ret = ring_buffer_read_page(iter->trace_buffer->buffer,
				    &info->spare,
				    count,
				    iter->cpu_file, 0);
	trace_access_unlock(iter->cpu_file);

	if (ret < 0) {
		if (trace_empty(iter)) {
			if ((filp->f_flags & O_NONBLOCK))
				return -EAGAIN;

			ret = wait_on_pipe(iter, false);
			if (ret)
				return ret;

			goto again;
		}
		return 0;
	}

	info->read = 0;
 read:
	size = PAGE_SIZE - info->read;
	if (size > count)
		size = count;

	ret = copy_to_user(ubuf, info->spare + info->read, size);
	if (ret == size)
		return -EFAULT;

	size -= ret;

	*ppos += size;
	info->read += size;

	return size;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
240
72.73%
13
65.00%
Zhao Lei
53
16.06%
1
5.00%
Lai Jiangshan
30
9.09%
2
10.00%
David Sharp
2
0.61%
1
5.00%
Rabin Vincent
2
0.61%
1
5.00%
Vaibhav Nagarnaik
2
0.61%
1
5.00%
Li Zefan
1
0.30%
1
5.00%
Total
330
100.00%
20
100.00%



static int tracing_buffers_release(struct inode *inode, struct file *file)
{
	struct ftrace_buffer_info *info = file->private_data;
	struct trace_iterator *iter = &info->iter;

	mutex_lock(&trace_types_lock);

	iter->tr->current_trace->ref--;

	__trace_array_put(iter->tr);

	if (info->spare)
		ring_buffer_free_read_page(iter->trace_buffer->buffer,
					   info->spare_cpu, info->spare);
	kfree(info);

	mutex_unlock(&trace_types_lock);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
44
46.81%
8
72.73%
Hiraku Toyooka
34
36.17%
1
9.09%
Li Zefan
14
14.89%
1
9.09%
Lai Jiangshan
2
2.13%
1
9.09%
Total
94
100.00%
11
100.00%


struct buffer_ref {
	
struct ring_buffer	*buffer;
	
void			*page;
	
int			cpu;
	
int			ref;
};



static void buffer_pipe_buf_release(struct pipe_inode_info *pipe,
				    struct pipe_buffer *buf)
{
	struct buffer_ref *ref = (struct buffer_ref *)buf->private;

	if (--ref->ref)
		return;

	ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
	kfree(ref);
	buf->private = 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
50
78.12%
2
66.67%
Hiraku Toyooka
14
21.88%
1
33.33%
Total
64
100.00%
3
100.00%



static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
				struct pipe_buffer *buf)
{
	struct buffer_ref *ref = (struct buffer_ref *)buf->private;

	ref->ref++;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
31
88.57%
1
50.00%
Hiraku Toyooka
4
11.43%
1
50.00%
Total
35
100.00%
2
100.00%

/* Pipe buffer operations for a buffer. */

static const struct pipe_buf_operations buffer_pipe_buf_ops = {
	.can_merge		= 0,
	.confirm		= generic_pipe_buf_confirm,
	.release		= buffer_pipe_buf_release,
	.steal			= generic_pipe_buf_steal,
	.get			= buffer_pipe_buf_get,
};

/*
 * Callback from splice_to_pipe(), if we need to release some pages
 * at the end of the spd in case we error'ed out in filling the pipe.
 */


static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i)
{
	struct buffer_ref *ref =
		(struct buffer_ref *)spd->partial[i].private;

	if (--ref->ref)
		return;

	ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
	kfree(ref);
	spd->partial[i].private = 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
71
97.26%
3
75.00%
Arnd Bergmann
2
2.74%
1
25.00%
Total
73
100.00%
4
100.00%


static ssize_t

tracing_buffers_splice_read(struct file *file, loff_t *ppos,
			    struct pipe_inode_info *pipe, size_t len,
			    unsigned int flags)
{
	struct ftrace_buffer_info *info = file->private_data;
	struct trace_iterator *iter = &info->iter;
	struct partial_page partial_def[PIPE_DEF_BUFFERS];
	struct page *pages_def[PIPE_DEF_BUFFERS];
	struct splice_pipe_desc spd = {
		.pages		= pages_def,
		.partial	= partial_def,
		.nr_pages_max	= PIPE_DEF_BUFFERS,
		.ops		= &buffer_pipe_buf_ops,
		.spd_release	= buffer_spd_release,
        };
	struct buffer_ref *ref;
	int entries, size, i;
	ssize_t ret = 0;

#ifdef CONFIG_TRACER_MAX_TRACE
	if (iter->snapshot && iter->tr->current_trace->use_max_tr)
		return -EBUSY;
#endif

	if (*ppos & (PAGE_SIZE - 1))
		return -EINVAL;

	if (len & (PAGE_SIZE - 1)) {
		if (len < PAGE_SIZE)
			return -EINVAL;
		len &= PAGE_MASK;
	}

	if (splice_grow_spd(pipe, &spd))
		return -ENOMEM;

 again:
	trace_access_lock(iter->cpu_file);
	entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);

	for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) {
		struct page *page;
		int r;

		ref = kzalloc(sizeof(*ref), GFP_KERNEL);
		if (!ref) {
			ret = -ENOMEM;
			break;
		}

		ref->ref = 1;
		ref->buffer = iter->trace_buffer->buffer;
		ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
		if (IS_ERR(ref->page)) {
			ret = PTR_ERR(ref->page);
			ref->page = NULL;
			kfree(ref);
			break;
		}
		ref->cpu = iter->cpu_file;

		r = ring_buffer_read_page(ref->buffer, &ref->page,
					  len, iter->cpu_file, 1);
		if (r < 0) {
			ring_buffer_free_read_page(ref->buffer, ref->cpu,
						   ref->page);
			kfree(ref);
			break;
		}

		/*
                 * zero out any left over data, this is going to
                 * user land.
                 */
		size = ring_buffer_page_len(ref->page);
		if (size < PAGE_SIZE)
			memset(ref->page + size, 0, PAGE_SIZE - size);

		page = virt_to_page(ref->page);

		spd.pages[i] = page;
		spd.partial[i].len = PAGE_SIZE;
		spd.partial[i].offset = 0;
		spd.partial[i].private = (unsigned long)ref;
		spd.nr_pages++;
		*ppos += PAGE_SIZE;

		entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);
	}

	trace_access_unlock(iter->cpu_file);
	spd.nr_pages = i;

	/* did we read anything? */
	if (!spd.nr_pages) {
		if (ret)
			goto out;

		ret = -EAGAIN;
		if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK))
			goto out;

		ret = wait_on_pipe(iter, true);
		if (ret)
			goto out;

		goto again;
	}

	ret = splice_to_pipe(pipe, &spd);
out:
	splice_shrink_spd(&spd);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
450
75.25%
15
45.45%
Lai Jiangshan
53
8.86%
3
9.09%
Al Viro
32
5.35%
2
6.06%
Rabin Vincent
18
3.01%
2
6.06%
Jens Axboe
11
1.84%
1
3.03%
Vaibhav Nagarnaik
9
1.51%
4
12.12%
Hiraku Toyooka
8
1.34%
1
3.03%
Zhao Lei
5
0.84%
1
3.03%
Arnd Bergmann
4
0.67%
1
3.03%
Pekka Paalanen
3
0.50%
1
3.03%
Li Zefan
3
0.50%
1
3.03%
Eric Dumazet
2
0.33%
1
3.03%
Total
598
100.00%
33
100.00%


static const struct file_operations tracing_buffers_fops = {
	.open		= tracing_buffers_open,
	.read		= tracing_buffers_read,
	.poll		= tracing_buffers_poll,
	.release	= tracing_buffers_release,
	.splice_read	= tracing_buffers_splice_read,
	.llseek		= no_llseek,
};


static ssize_t

tracing_stats_read(struct file *filp, char __user *ubuf,
		   size_t count, loff_t *ppos)
{
	struct inode *inode = file_inode(filp);
	struct trace_array *tr = inode->i_private;
	struct trace_buffer *trace_buf = &tr->trace_buffer;
	int cpu = tracing_get_cpu(inode);
	struct trace_seq *s;
	unsigned long cnt;
	unsigned long long t;
	unsigned long usec_rem;

	s = kmalloc(sizeof(*s), GFP_KERNEL);
	if (!s)
		return -ENOMEM;

	trace_seq_init(s);

	cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu);
	trace_seq_printf(s, "entries: %ld\n", cnt);

	cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu);
	trace_seq_printf(s, "overrun: %ld\n", cnt);

	cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu);
	trace_seq_printf(s, "commit overrun: %ld\n", cnt);

	cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu);
	trace_seq_printf(s, "bytes: %ld\n", cnt);

	if (trace_clocks[tr->clock_id].in_ns) {
		/* local or global for trace_clock */
		t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu));
		usec_rem = do_div(t, USEC_PER_SEC);
		trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n",
								t, usec_rem);

		t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu));
		usec_rem = do_div(t, USEC_PER_SEC);
		trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem);
	} else {
		/* counter or tsc mode for trace_clock */
		trace_seq_printf(s, "oldest event ts: %llu\n",
				ring_buffer_oldest_event_ts(trace_buf->buffer, cpu));

		trace_seq_printf(s, "now ts: %llu\n",
				ring_buffer_time_stamp(trace_buf->buffer, cpu));
	}

	cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu);
	trace_seq_printf(s, "dropped events: %ld\n", cnt);

	cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu);
	trace_seq_printf(s, "read events: %ld\n", cnt);

	count = simple_read_from_buffer(ubuf, count, ppos,
					s->buffer, trace_seq_used(s));

	kfree(s);

	return count;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
212
57.14%
8
44.44%
Vaibhav Nagarnaik
78
21.02%
2
11.11%
Yoshihiro Yunomae
33
8.89%
2
11.11%
Lai Jiangshan
21
5.66%
2
11.11%
Oleg Nesterov
15
4.04%
1
5.56%
Slava Pestov
10
2.70%
1
5.56%
Li Zefan
1
0.27%
1
5.56%
Roel Kluin
1
0.27%
1
5.56%
Total
371
100.00%
18
100.00%


static const struct file_operations tracing_stats_fops = {
	.open		= tracing_open_generic_tr,
	.read		= tracing_stats_read,
	.llseek		= generic_file_llseek,
	.release	= tracing_release_generic_tr,
};

#ifdef CONFIG_DYNAMIC_FTRACE


static ssize_t

tracing_read_dyn_info(struct file *filp, char __user *ubuf,
		  size_t cnt, loff_t *ppos)
{
	unsigned long *p = filp->private_data;
	char buf[64]; /* Not too big for a shallow stack */
	int r;

	r = scnprintf(buf, 63, "%ld", *p);
	buf[r++] = '\n';

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
78
100.00%
4
100.00%
Total
78
100.00%
4
100.00%


static const struct file_operations tracing_dyn_info_fops = {
	.open		= tracing_open_generic,
	.read		= tracing_read_dyn_info,
	.llseek		= generic_file_llseek,
};
#endif /* CONFIG_DYNAMIC_FTRACE */

#if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE)

static void

ftrace_snapshot(unsigned long ip, unsigned long parent_ip,
		struct trace_array *tr, struct ftrace_probe_ops *ops,
		void *data)
{
	tracing_snapshot_instance(tr);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
33
100.00%
5
100.00%
Total
33
100.00%
5
100.00%


static void

ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip,
		      struct trace_array *tr, struct ftrace_probe_ops *ops,
		      void *data)
{
	struct ftrace_func_mapper *mapper = data;
	long *count = NULL;

	if (mapper)
		count = (long *)ftrace_func_mapper_find_ip(mapper, ip);

	if (count) {

		if (*count <= 0)
			return;

		(*count)--;
	}

	tracing_snapshot_instance(tr);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
83
100.00%
7
100.00%
Total
83
100.00%
7
100.00%


static int

ftrace_snapshot_print(struct seq_file *m, unsigned long ip,
		      struct ftrace_probe_ops *ops, void *data)
{
	struct ftrace_func_mapper *mapper = data;
	long *count = NULL;

	seq_printf(m, "%ps:", (void *)ip);

	seq_puts(m, "snapshot");

	if (mapper)
		count = (long *)ftrace_func_mapper_find_ip(mapper, ip);

	if (count)
		seq_printf(m, ":count=%ld\n", *count);
	else
		seq_puts(m, ":unlimited\n");

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
88
88.89%
5
55.56%
Lai Jiangshan
7
7.07%
2
22.22%
Jens Axboe
3
3.03%
1
11.11%
Rasmus Villemoes
1
1.01%
1
11.11%
Total
99
100.00%
9
100.00%


static int

ftrace_snapshot_init(struct ftrace_probe_ops *ops, struct trace_array *tr,
		     unsigned long ip, void *init_data, void **data)
{
	struct ftrace_func_mapper *mapper = *data;

	if (!mapper) {
		mapper = allocate_ftrace_func_mapper();
		if (!mapper)
			return -ENOMEM;
		*data = mapper;
	}

	return ftrace_func_mapper_add_ip(mapper, ip, init_data);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
73
100.00%
3
100.00%
Total
73
100.00%
3
100.00%


static void

ftrace_snapshot_free(struct ftrace_probe_ops *ops, struct trace_array *tr,
		     unsigned long ip, void *data)
{
	struct ftrace_func_mapper *mapper = data;

	if (!ip) {
		if (!mapper)
			return;
		free_ftrace_func_mapper(mapper, NULL);
		return;
	}

	ftrace_func_mapper_remove_ip(mapper, ip);
}

Contributors
Person
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CommitProp
Steven Rostedt
59
100.00%
3
100.00%
Total
59
100.00%
3
100.00%


static struct ftrace_probe_ops snapshot_probe_ops = {
	.func			= ftrace_snapshot,
	.print			= ftrace_snapshot_print,
};


static struct ftrace_probe_ops snapshot_count_probe_ops = {
	.func			= ftrace_count_snapshot,
	.print			= ftrace_snapshot_print,
	.init			= ftrace_snapshot_init,
	.free			= ftrace_snapshot_free,
};


static int

ftrace_trace_snapshot_callback(struct trace_array *tr, struct ftrace_hash *hash,
			       char *glob, char *cmd, char *param, int enable)
{
	struct ftrace_probe_ops *ops;
	void *count = (void *)-1;
	char *number;
	int ret;

	if (!tr)
		return -ENODEV;

	/* hash funcs only work with set_ftrace_filter */
	if (!enable)
		return -EINVAL;

	ops = param ? &snapshot_count_probe_ops :  &snapshot_probe_ops;

	if (glob[0] == '!')
		return unregister_ftrace_function_probe_func(glob+1, tr, ops);

	if (!param)
		goto out_reg;

	number = strsep(&param, ":");

	if (!strlen(number))
		goto out_reg;

	/*
         * We use the callback data field (which is a pointer)
         * as our counter.
         */
	ret = kstrtoul(number, 0, (unsigned long *)&count);
	if (ret)
		return ret;

 out_reg:
	ret = alloc_snapshot(tr);
	if (ret < 0)
		goto out;

	ret = register_ftrace_function_probe(glob, tr, ops, count);

 out:
	return ret < 0 ? ret : 0;
}

Contributors
Person
Tokens
Prop
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CommitProp
Steven Rostedt
199
99.50%
9
90.00%
Linus Torvalds
1
0.50%
1
10.00%
Total
200
100.00%
10
100.00%


static struct ftrace_func_command ftrace_snapshot_cmd = {
	.name			= "snapshot",
	.func			= ftrace_trace_snapshot_callback,
};



static __init int register_snapshot_cmd(void)
{
	return register_ftrace_command(&ftrace_snapshot_cmd);
}
Contributors
Person
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CommitProp
Steven Rostedt
15
93.75%
3
75.00%
Tom Zanussi
1
6.25%
1
25.00%
Total
16
100.00%
4
100.00%

#else


static inline __init int register_snapshot_cmd(void) { return 0; }
Contributors
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Steven Rostedt
12
92.31%
1
50.00%
Tom Zanussi
1
7.69%
1
50.00%
Total
13
100.00%
2
100.00%

#endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */



static struct dentry *tracing_get_dentry(struct trace_array *tr)
{
	if (WARN_ON(!tr->dir))
		return ERR_PTR(-ENODEV);

	/* Top directory uses NULL as the parent */
	if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
		return NULL;

	/* All sub buffers have a descriptor */
	return tr->dir;
}

Contributors
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Steven Rostedt
48
100.00%
5
100.00%
Total
48
100.00%
5
100.00%



static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu)
{
	struct dentry *d_tracer;

	if (tr->percpu_dir)
		return tr->percpu_dir;

	d_tracer = tracing_get_dentry(tr);
	if (IS_ERR(d_tracer))
		return NULL;

	tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer);

	WARN_ONCE(!tr->percpu_dir,
		  "Could not create tracefs directory 'per_cpu/%d'\n", cpu);

	return tr->percpu_dir;
}

Contributors
Person
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CommitProp
Steven Rostedt
55
71.43%
5
71.43%
Frédéric Weisbecker
21
27.27%
1
14.29%
Vaibhav Nagarnaik
1
1.30%
1
14.29%
Total
77
100.00%
7
100.00%


static struct dentry *

trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent,
		      void *data, long cpu, const struct file_operations *fops)
{
	struct dentry *ret = trace_create_file(name, mode, parent, data, fops);

	if (ret) /* See tracing_get_cpu() */
		d_inode(ret)->i_cdev = (void *)(cpu + 1);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Oleg Nesterov
73
94.81%
1
33.33%
David Howells
3
3.90%
1
33.33%
Frédéric Weisbecker
1
1.30%
1
33.33%
Total
77
100.00%
3
100.00%


static void

tracing_init_tracefs_percpu(struct trace_array *tr, long cpu)
{
	struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu);
	struct dentry *d_cpu;
	char cpu_dir[30]; /* 30 characters should be more than enough */

	if (!d_percpu)
		return;

	snprintf(cpu_dir, 30, "cpu%ld", cpu);
	d_cpu = tracefs_create_dir(cpu_dir, d_percpu);
	if (!d_cpu) {
		pr_warn("Could not create tracefs '%s' entry\n", cpu_dir);
		return;
	}

	/* per cpu trace_pipe */
	trace_create_cpu_file("trace_pipe", 0444, d_cpu,
				tr, cpu, &tracing_pipe_fops);

	/* per cpu trace */
	trace_create_cpu_file("trace", 0644, d_cpu,
				tr, cpu, &tracing_fops);

	trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu,
				tr, cpu, &tracing_buffers_fops);

	trace_create_cpu_file("stats", 0444, d_cpu,
				tr, cpu, &tracing_stats_fops);

	trace_create_cpu_file("buffer_size_kb", 0444, d_cpu,
				tr, cpu, &tracing_entries_fops);

#ifdef CONFIG_TRACER_SNAPSHOT
	trace_create_cpu_file("snapshot", 0644, d_cpu,
				tr, cpu, &snapshot_fops);

	trace_create_cpu_file("snapshot_raw", 0444, d_cpu,
				tr, cpu, &snapshot_raw_fops);
#endif
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
65
32.83%
9
39.13%
Frédéric Weisbecker
45
22.73%
2
8.70%
Vaibhav Nagarnaik
32
16.16%
2
8.70%
Oleg Nesterov
29
14.65%
6
26.09%
Yoshihiro Yunomae
14
7.07%
1
4.35%
Slava Pestov
6
3.03%
1
4.35%
Namhyung Kim
6
3.03%
1
4.35%
Joe Perches
1
0.51%
1
4.35%
Total
198
100.00%
23
100.00%

#ifdef CONFIG_FTRACE_SELFTEST
/* Let selftest have access to static functions in this file */
#include "trace_selftest.c"
#endif


static ssize_t

trace_options_read(struct file *filp, char __user *ubuf, size_t cnt,
			loff_t *ppos)
{
	struct trace_option_dentry *topt = filp->private_data;
	char *buf;

	if (topt->flags->val & topt->opt->bit)
		buf = "1\n";
	else
		buf = "0\n";

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
73
100.00%
3
100.00%
Total
73
100.00%
3
100.00%


static ssize_t

trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt,
			 loff_t *ppos)
{
	struct trace_option_dentry *topt = filp->private_data;
	unsigned long val;
	int ret;

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	if (val != 0 && val != 1)
		return -EINVAL;

	if (!!(topt->flags->val & topt->opt->bit) != val) {
		mutex_lock(&trace_types_lock);
		ret = __set_tracer_option(topt->tr, topt->flags,
					  topt->opt, !val);
		mutex_unlock(&trace_types_lock);
		if (ret)
			return ret;
	}

	*ppos += cnt;

	return cnt;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
125
86.81%
7
77.78%
Li Zefan
16
11.11%
1
11.11%
Peter Hüwe
3
2.08%
1
11.11%
Total
144
100.00%
9
100.00%


static const struct file_operations trace_options_fops = {
	.open = tracing_open_generic,
	.read = trace_options_read,
	.write = trace_options_write,
	.llseek	= generic_file_llseek,
};

/*
 * In order to pass in both the trace_array descriptor as well as the index
 * to the flag that the trace option file represents, the trace_array
 * has a character array of trace_flags_index[], which holds the index
 * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc.
 * The address of this character array is passed to the flag option file
 * read/write callbacks.
 *
 * In order to extract both the index and the trace_array descriptor,
 * get_tr_index() uses the following algorithm.
 *
 *   idx = *ptr;
 *
 * As the pointer itself contains the address of the index (remember
 * index[1] == 1).
 *
 * Then to get the trace_array descriptor, by subtracting that index
 * from the ptr, we get to the start of the index itself.
 *
 *   ptr - idx == &index[0]
 *
 * Then a simple container_of() from that pointer gets us to the
 * trace_array descriptor.
 */


static void get_tr_index(void *data, struct trace_array **ptr,
			 unsigned int *pindex)
{
	*pindex = *(unsigned char *)data;

	*ptr = container_of(data - *pindex, struct trace_array,
			    trace_flags_index);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
48
100.00%
1
100.00%
Total
48
100.00%
1
100.00%


static ssize_t

trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt,
			loff_t *ppos)
{
	void *tr_index = filp->private_data;
	struct trace_array *tr;
	unsigned int index;
	char *buf;

	get_tr_index(tr_index, &tr, &index);

	if (tr->trace_flags & (1 << index))
		buf = "1\n";
	else
		buf = "0\n";

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
75
83.33%
3
75.00%
Frédéric Weisbecker
15
16.67%
1
25.00%
Total
90
100.00%
4
100.00%


static ssize_t

trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
			 loff_t *ppos)
{
	void *tr_index = filp->private_data;
	struct trace_array *tr;
	unsigned int index;
	unsigned long val;
	int ret;

	get_tr_index(tr_index, &tr, &index);

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	if (val != 0 && val != 1)
		return -EINVAL;

	mutex_lock(&trace_types_lock);
	ret = set_tracer_flag(tr, 1 << index, val);
	mutex_unlock(&trace_types_lock);

	if (ret < 0)
		return ret;

	*ppos += cnt;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
94
69.12%
6
60.00%
Frédéric Weisbecker
29
21.32%
2
20.00%
Zhao Lei
10
7.35%
1
10.00%
Peter Hüwe
3
2.21%
1
10.00%
Total
136
100.00%
10
100.00%


static const struct file_operations trace_options_core_fops = {
	.open = tracing_open_generic,
	.read = trace_options_core_read,
	.write = trace_options_core_write,
	.llseek = generic_file_llseek,
};



struct dentry *trace_create_file(const char *name,
				 umode_t mode,
				 struct dentry *parent,
				 void *data,
				 const struct file_operations *fops)
{
	struct dentry *ret;

	ret = tracefs_create_file(name, mode, parent, data, fops);
	if (!ret)
		pr_warn("Could not create tracefs '%s' entry\n", name);

	return ret;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Frédéric Weisbecker
49
75.38%
2
25.00%
Steven Rostedt
10
15.38%
3
37.50%
Vaibhav Nagarnaik
4
6.15%
1
12.50%
Al Viro
1
1.54%
1
12.50%
Joe Perches
1
1.54%
1
12.50%
Total
65
100.00%
8
100.00%



static struct dentry *trace_options_init_dentry(struct trace_array *tr)
{
	struct dentry *d_tracer;

	if (tr->options)
		return tr->options;

	d_tracer = tracing_get_dentry(tr);
	if (IS_ERR(d_tracer))
		return NULL;

	tr->options = tracefs_create_dir("options", d_tracer);
	if (!tr->options) {
		pr_warn("Could not create tracefs directory 'options'\n");
		return NULL;
	}

	return tr->options;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
78
98.73%
5
83.33%
Joe Perches
1
1.27%
1
16.67%
Total
79
100.00%
6
100.00%


static void

create_trace_option_file(struct trace_array *tr,
			 struct trace_option_dentry *topt,
			 struct tracer_flags *flags,
			 struct tracer_opt *opt)
{
	struct dentry *t_options;

	t_options = trace_options_init_dentry(tr);
	if (!t_options)
		return;

	topt->flags = flags;
	topt->opt = opt;
	topt->tr = tr;

	topt->entry = trace_create_file(opt->name, 0644, t_options, topt,
				    &trace_options_fops);

}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
79
96.34%
3
75.00%
Frédéric Weisbecker
3
3.66%
1
25.00%
Total
82
100.00%
4
100.00%


static void

create_trace_option_files(struct trace_array *tr, struct tracer *tracer)
{
	struct trace_option_dentry *topts;
	struct trace_options *tr_topts;
	struct tracer_flags *flags;
	struct tracer_opt *opts;
	int cnt;
	int i;

	if (!tracer)
		return;

	flags = tracer->flags;

	if (!flags || !flags->opts)
		return;

	/*
         * If this is an instance, only create flags for tracers
         * the instance may have.
         */
	if (!trace_ok_for_array(tracer, tr))
		return;

	for (i = 0; i < tr->nr_topts; i++) {
		/* Make sure there's no duplicate flags. */
		if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags))
			return;
	}

	opts = flags->opts;

	for (cnt = 0; opts[cnt].name; cnt++)
		;

	topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL);
	if (!topts)
		return;

	tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1),
			    GFP_KERNEL);
	if (!tr_topts) {
		kfree(topts);
		return;
	}

	tr->topts = tr_topts;
	tr->topts[tr->nr_topts].tracer = tracer;
	tr->topts[tr->nr_topts].topts = topts;
	tr->nr_topts++;

	for (cnt = 0; opts[cnt].name; cnt++) {
		create_trace_option_file(tr, &topts[cnt], flags,
					 &opts[cnt]);
		WARN_ONCE(topts[cnt].entry == NULL,
			  "Failed to create trace option: %s",
			  opts[cnt].name);
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
292
98.32%
6
75.00%
Chunyu Hu
4
1.35%
1
12.50%
Peter Hüwe
1
0.34%
1
12.50%
Total
297
100.00%
8
100.00%


static struct dentry *

create_trace_option_core_file(struct trace_array *tr,
			      const char *option, long index)
{
	struct dentry *t_options;

	t_options = trace_options_init_dentry(tr);
	if (!t_options)
		return NULL;

	return trace_create_file(option, 0644, t_options,
				 (void *)&tr->trace_flags_index[index],
				 &trace_options_core_fops);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
65
98.48%
4
80.00%
Frédéric Weisbecker
1
1.52%
1
20.00%
Total
66
100.00%
5
100.00%



static void create_trace_options_dir(struct trace_array *tr)
{
	struct dentry *t_options;
	bool top_level = tr == &global_trace;
	int i;

	t_options = trace_options_init_dentry(tr);
	if (!t_options)
		return;

	for (i = 0; trace_options[i]; i++) {
		if (top_level ||
		    !((1 << i) & TOP_LEVEL_TRACE_FLAGS))
			create_trace_option_core_file(tr, trace_options[i], i);
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
82
98.80%
3
75.00%
Arnd Bergmann
1
1.20%
1
25.00%
Total
83
100.00%
4
100.00%


static ssize_t

rb_simple_read(struct file *filp, char __user *ubuf,
	       size_t cnt, loff_t *ppos)
{
	struct trace_array *tr = filp->private_data;
	char buf[64];
	int r;

	r = tracer_tracing_is_on(tr);
	r = sprintf(buf, "%d\n", r);

	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
73
100.00%
5
100.00%
Total
73
100.00%
5
100.00%


static ssize_t

rb_simple_write(struct file *filp, const char __user *ubuf,
		size_t cnt, loff_t *ppos)
{
	struct trace_array *tr = filp->private_data;
	struct ring_buffer *buffer = tr->trace_buffer.buffer;
	unsigned long val;
	int ret;

	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
	if (ret)
		return ret;

	if (buffer) {
		mutex_lock(&trace_types_lock);
		if (val) {
			tracer_tracing_on(tr);
			if (tr->current_trace->start)
				tr->current_trace->start(tr);
		} else {
			tracer_tracing_off(tr);
			if (tr->current_trace->stop)
				tr->current_trace->stop(tr);
		}
		mutex_unlock(&trace_types_lock);
	}

	(*ppos)++;

	return cnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
144
94.74%
9
81.82%
Zhao Lei
5
3.29%
1
9.09%
Peter Hüwe
3
1.97%
1
9.09%
Total
152
100.00%
11
100.00%


static const struct file_operations rb_simple_fops = {
	.open		= tracing_open_generic_tr,
	.read		= rb_simple_read,
	.write		= rb_simple_write,
	.release	= tracing_release_generic_tr,
	.llseek		= default_llseek,
};


struct dentry *trace_instance_dir;

static void
init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer);


static int

allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size)
{
	enum ring_buffer_flags rb_flags;

	rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;

	buf->tr = tr;

	buf->buffer = ring_buffer_alloc(size, rb_flags);
	if (!buf->buffer)
		return -ENOMEM;

	buf->data = alloc_percpu(struct trace_array_cpu);
	if (!buf->data) {
		ring_buffer_free(buf->buffer);
		return -ENOMEM;
	}

	/* Allocate the first page for all buffers */
	set_buffer_entries(&tr->trace_buffer,
			   ring_buffer_size(tr->trace_buffer.buffer, 0));

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
104
89.66%
6
85.71%
Frédéric Weisbecker
12
10.34%
1
14.29%
Total
116
100.00%
7
100.00%



static int allocate_trace_buffers(struct trace_array *tr, int size)
{
	int ret;

	ret = allocate_trace_buffer(tr, &tr->trace_buffer, size);
	if (ret)
		return ret;

#ifdef CONFIG_TRACER_MAX_TRACE
	ret = allocate_trace_buffer(tr, &tr->max_buffer,
				    allocate_snapshot ? size : 1);
	if (WARN_ON(ret)) {
		ring_buffer_free(tr->trace_buffer.buffer);
		free_percpu(tr->trace_buffer.data);
		return -ENOMEM;
	}
	tr->allocated_snapshot = allocate_snapshot;

	/*
         * Only the top level trace array gets its snapshot allocated
         * from the kernel command line.
         */
	allocate_snapshot = false;
#endif
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
106
100.00%
5
100.00%
Total
106
100.00%
5
100.00%



static void free_trace_buffer(struct trace_buffer *buf)
{
	if (buf->buffer) {
		ring_buffer_free(buf->buffer);
		buf->buffer = NULL;
		free_percpu(buf->data);
		buf->data = NULL;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
45
100.00%
2
100.00%
Total
45
100.00%
2
100.00%



static void free_trace_buffers(struct trace_array *tr)
{
	if (!tr)
		return;

	free_trace_buffer(&tr->trace_buffer);

#ifdef CONFIG_TRACER_MAX_TRACE
	free_trace_buffer(&tr->max_buffer);
#endif
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
38
100.00%
2
100.00%
Total
38
100.00%
2
100.00%



static void init_trace_flags_index(struct trace_array *tr)
{
	int i;

	/* Used by the trace options files */
	for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++)
		tr->trace_flags_index[i] = i;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
37
100.00%
1
100.00%
Total
37
100.00%
1
100.00%



static void __update_tracer_options(struct trace_array *tr)
{
	struct tracer *t;

	for (t = trace_types; t; t = t->next)
		add_tracer_options(tr, t);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
37
100.00%
1
100.00%
Total
37
100.00%
1
100.00%



static void update_tracer_options(struct trace_array *tr)
{
	mutex_lock(&trace_types_lock);
	__update_tracer_options(tr);
	mutex_unlock(&trace_types_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
28
100.00%
1
100.00%
Total
28
100.00%
1
100.00%



static int instance_mkdir(const char *name)
{
	struct trace_array *tr;
	int ret;

	mutex_lock(&trace_types_lock);

	ret = -EEXIST;
	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
		if (tr->name && strcmp(tr->name, name) == 0)
			goto out_unlock;
	}

	ret = -ENOMEM;
	tr = kzalloc(sizeof(*tr), GFP_KERNEL);
	if (!tr)
		goto out_unlock;

	tr->name = kstrdup(name, GFP_KERNEL);
	if (!tr->name)
		goto out_free_tr;

	if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL))
		goto out_free_tr;

	tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS;

	cpumask_copy(tr->tracing_cpumask, cpu_all_mask);

	raw_spin_lock_init(&tr->start_lock);

	tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;

	tr->current_trace = &nop_trace;

	INIT_LIST_HEAD(&tr->systems);
	INIT_LIST_HEAD(&tr->events);

	if (allocate_trace_buffers(tr, trace_buf_size) < 0)
		goto out_free_tr;

	tr->dir = tracefs_create_dir(name, trace_instance_dir);
	if (!tr->dir)
		goto out_free_tr;

	ret = event_trace_add_tracer(tr->dir, tr);
	if (ret) {
		tracefs_remove_recursive(tr->dir);
		goto out_free_tr;
	}

	ftrace_init_trace_array(tr);

	init_tracer_tracefs(tr, tr->dir);
	init_trace_flags_index(tr);
	__update_tracer_options(tr);

	list_add(&tr->list, &ftrace_trace_arrays);

	mutex_unlock(&trace_types_lock);

	return 0;

 out_free_tr:
	free_trace_buffers(tr);
	free_cpumask_var(tr->tracing_cpumask);
	kfree(tr->name);
	kfree(tr);

 out_unlock:
	mutex_unlock(&trace_types_lock);

	return ret;

}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
285
87.42%
13
81.25%
Alexander Z Lam
40
12.27%
2
12.50%
Frédéric Weisbecker
1
0.31%
1
6.25%
Total
326
100.00%
16
100.00%



static int instance_rmdir(const char *name)
{
	struct trace_array *tr;
	int found = 0;
	int ret;
	int i;

	mutex_lock(&trace_types_lock);

	ret = -ENODEV;
	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
		if (tr->name && strcmp(tr->name, name) == 0) {
			found = 1;
			break;
		}
	}
	if (!found)
		goto out_unlock;

	ret = -EBUSY;
	if (tr->ref || (tr->current_trace && tr->current_trace->ref))
		goto out_unlock;

	list_del(&tr->list);

	/* Disable all the flags that were enabled coming in */
	for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) {
		if ((1 << i) & ZEROED_TRACE_FLAGS)
			set_tracer_flag(tr, 1 << i, 0);
	}

	tracing_set_nop(tr);
	clear_ftrace_function_probes(tr);
	event_trace_del_tracer(tr);
	ftrace_clear_pids(tr);
	ftrace_destroy_function_files(tr);
	tracefs_remove_recursive(tr->dir);
	free_trace_buffers(tr);

	for (i = 0; i < tr->nr_topts; i++) {
		kfree(tr->topts[i].topts);
	}
	kfree(tr->topts);

	free_cpumask_var(tr->tracing_cpumask);
	kfree(tr->name);
	kfree(tr);

	ret = 0;

 out_unlock:
	mutex_unlock(&trace_types_lock);

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
240
93.02%
10
71.43%
Chunyu Hu
7
2.71%
1
7.14%
Naveen N. Rao
5
1.94%
1
7.14%
Namhyung Kim
5
1.94%
1
7.14%
Jiaxing Wang
1
0.39%
1
7.14%
Total
258
100.00%
14
100.00%



static __init void create_trace_instances(struct dentry *d_tracer)
{
	trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer,
							 instance_mkdir,
							 instance_rmdir);
	if (WARN_ON(!trace_instance_dir))
		return;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
34
100.00%
3
100.00%
Total
34
100.00%
3
100.00%


static void

init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
{
	int cpu;

	trace_create_file("available_tracers", 0444, d_tracer,
			tr, &show_traces_fops);

	trace_create_file("current_tracer", 0644, d_tracer,
			tr, &set_tracer_fops);

	trace_create_file("tracing_cpumask", 0644, d_tracer,
			  tr, &tracing_cpumask_fops);

	trace_create_file("trace_options", 0644, d_tracer,
			  tr, &tracing_iter_fops);

	trace_create_file("trace", 0644, d_tracer,
			  tr, &tracing_fops);

	trace_create_file("trace_pipe", 0444, d_tracer,
			  tr, &tracing_pipe_fops);

	trace_create_file("buffer_size_kb", 0644, d_tracer,
			  tr, &tracing_entries_fops);

	trace_create_file("buffer_total_size_kb", 0444, d_tracer,
			  tr, &tracing_total_entries_fops);

	trace_create_file("free_buffer", 0200, d_tracer,
			  tr, &tracing_free_buffer_fops);

	trace_create_file("trace_marker", 0220, d_tracer,
			  tr, &tracing_mark_fops);

	trace_create_file("trace_marker_raw", 0220, d_tracer,
			  tr, &tracing_mark_raw_fops);

	trace_create_file("trace_clock", 0644, d_tracer, tr,
			  &trace_clock_fops);

	trace_create_file("tracing_on", 0644, d_tracer,
			  tr, &rb_simple_fops);

	create_trace_options_dir(tr);

#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
	trace_create_file("tracing_max_latency", 0644, d_tracer,
			&tr->max_latency, &tracing_max_lat_fops);
#endif

	if (ftrace_create_function_files(tr, d_tracer))
		WARN(1, "Could not allocate function filter files");

#ifdef CONFIG_TRACER_SNAPSHOT
	trace_create_file("snapshot", 0644, d_tracer,
			  tr, &snapshot_fops);
#endif

	for_each_tracing_cpu(cpu)
		tracing_init_tracefs_percpu(tr, cpu);

	ftrace_init_tracefs(tr, d_tracer);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
259
89.62%
17
80.95%
Alexander Z Lam
14
4.84%
1
4.76%
Frédéric Weisbecker
9
3.11%
1
4.76%
Ingo Molnar
6
2.08%
1
4.76%
Wang YanQing
1
0.35%
1
4.76%
Total
289
100.00%
21
100.00%



static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore)
{
	struct vfsmount *mnt;
	struct file_system_type *type;

	/*
         * To maintain backward compatibility for tools that mount
         * debugfs to get to the tracing facility, tracefs is automatically
         * mounted to the debugfs/tracing directory.
         */
	type = get_fs_type("tracefs");
	if (!type)
		return NULL;
	mnt = vfs_submount(mntpt, type, "tracefs", NULL);
	put_filesystem(type);
	if (IS_ERR(mnt))
		return NULL;
	mntget(mnt);

	return mnt;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
71
89.87%
1
50.00%
Eric W. Biedermann
8
10.13%
1
50.00%
Total
79
100.00%
2
100.00%

/**
 * tracing_init_dentry - initialize top level trace array
 *
 * This is called when creating files or directories in the tracing
 * directory. It is called via fs_initcall() by any of the boot up code
 * and expects to return the dentry of the top level tracing directory.
 */


struct dentry *tracing_init_dentry(void)
{
	struct trace_array *tr = &global_trace;

	/* The top level trace array uses  NULL as parent */
	if (tr->dir)
		return NULL;

	if (WARN_ON(!tracefs_initialized()) ||
		(IS_ENABLED(CONFIG_DEBUG_FS) &&
		 WARN_ON(!debugfs_initialized())))
		return ERR_PTR(-ENODEV);

	/*
         * As there may still be users that expect the tracing
         * files to exist in debugfs/tracing, we must automount
         * the tracefs file system there, so older tools still
         * work with the newer kerenl.
         */
	tr->dir = debugfs_create_automount("tracing", NULL,
					   trace_automount, NULL);
	if (!tr->dir) {
		pr_warn_once("Could not create debugfs directory 'tracing'\n");
		return ERR_PTR(-ENOMEM);
	}

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
74
76.29%
1
33.33%
Jiaxing Wang
14
14.43%
1
33.33%
Linus Torvalds
9
9.28%
1
33.33%
Total
97
100.00%
3
100.00%

extern struct trace_eval_map *__start_ftrace_eval_maps[];
extern struct trace_eval_map *__stop_ftrace_eval_maps[];



static void __init trace_eval_init(void)
{
	int len;

	len = __stop_ftrace_eval_maps - __start_ftrace_eval_maps;
	trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
22
81.48%
3
50.00%
Jeremy Linton
5
18.52%
3
50.00%
Total
27
100.00%
6
100.00%

#ifdef CONFIG_MODULES


static void trace_module_add_evals(struct module *mod)
{
	if (!mod->num_trace_evals)
		return;

	/*
         * Modules with bad taint do not have events created, do
         * not bother with enums either.
         */
	if (trace_module_has_bad_taint(mod))
		return;

	trace_insert_eval_map(mod, mod->trace_evals, mod->num_trace_evals);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
36
87.80%
2
50.00%
Jeremy Linton
5
12.20%
2
50.00%
Total
41
100.00%
4
100.00%

#ifdef CONFIG_TRACE_EVAL_MAP_FILE


static void trace_module_remove_evals(struct module *mod)
{
	union trace_eval_map_item *map;
	union trace_eval_map_item **last = &trace_eval_maps;

	if (!mod->num_trace_evals)
		return;

	mutex_lock(&trace_eval_mutex);

	map = trace_eval_maps;

	while (map) {
		if (map->head.mod == mod)
			break;
		map = trace_eval_jmp_to_tail(map);
		last = &map->tail.next;
		map = map->tail.next;
	}
	if (!map)
		goto out;

	*last = trace_eval_jmp_to_tail(map)->tail.next;
	kfree(map);
 out:
	mutex_unlock(&trace_eval_mutex);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
107
91.45%
2
28.57%
Jeremy Linton
10
8.55%
5
71.43%
Total
117
100.00%
7
100.00%

#else


static inline void trace_module_remove_evals(struct module *mod) { }
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
10
90.91%
1
50.00%
Jeremy Linton
1
9.09%
1
50.00%
Total
11
100.00%
2
100.00%

#endif /* CONFIG_TRACE_EVAL_MAP_FILE */



static int trace_module_notify(struct notifier_block *self,
			       unsigned long val, void *data)
{
	struct module *mod = data;

	switch (val) {
	case MODULE_STATE_COMING:
		trace_module_add_evals(mod);
		break;
	case MODULE_STATE_GOING:
		trace_module_remove_evals(mod);
		break;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
51
96.23%
3
75.00%
Jeremy Linton
2
3.77%
1
25.00%
Total
53
100.00%
4
100.00%


static struct notifier_block trace_module_nb = {
	.notifier_call = trace_module_notify,
	.priority = 0,
};
#endif /* CONFIG_MODULES */



static __init int tracer_init_tracefs(void)
{
	struct dentry *d_tracer;

	trace_access_lock_init();

	d_tracer = tracing_init_dentry();
	if (IS_ERR(d_tracer))
		return 0;

	init_tracer_tracefs(&global_trace, d_tracer);
	ftrace_init_tracefs_toplevel(&global_trace, d_tracer);

	trace_create_file("tracing_thresh", 0644, d_tracer,
			&global_trace, &tracing_thresh_fops);

	trace_create_file("README", 0444, d_tracer,
			NULL, &tracing_readme_fops);

	trace_create_file("saved_cmdlines", 0444, d_tracer,
			NULL, &tracing_saved_cmdlines_fops);

	trace_create_file("saved_cmdlines_size", 0644, d_tracer,
			  NULL, &tracing_saved_cmdlines_size_fops);

	trace_create_file("saved_tgids", 0444, d_tracer,
			NULL, &tracing_saved_tgids_fops);

	trace_eval_init();

	trace_create_eval_file(d_tracer);

#ifdef CONFIG_MODULES
	register_module_notifier(&trace_module_nb);
#endif

#ifdef CONFIG_DYNAMIC_FTRACE
	trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
			&ftrace_update_tot_cnt, &tracing_dyn_info_fops);
#endif

	create_trace_instances(d_tracer);

	update_tracer_options(&global_trace);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
81
47.09%
12
42.86%
Frédéric Weisbecker
24
13.95%
3
10.71%
Yoshihiro Yunomae
14
8.14%
1
3.57%
Michael Sartain
14
8.14%
1
3.57%
Lai Jiangshan
13
7.56%
3
10.71%
Avadh Patel
10
5.81%
1
3.57%
Namhyung Kim
6
3.49%
1
3.57%
Hiraku Toyooka
4
2.33%
1
3.57%
Jeremy Linton
2
1.16%
2
7.14%
Stanislav Fomichev
2
1.16%
1
3.57%
Li Zefan
1
0.58%
1
3.57%
Ingo Molnar
1
0.58%
1
3.57%
Total
172
100.00%
28
100.00%



static int trace_panic_handler(struct notifier_block *this,
			       unsigned long event, void *unused)
{
	if (ftrace_dump_on_oops)
		ftrace_dump(ftrace_dump_on_oops);
	return NOTIFY_OK;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
28
90.32%
4
80.00%
Frédéric Weisbecker
3
9.68%
1
20.00%
Total
31
100.00%
5
100.00%


static struct notifier_block trace_panic_notifier = {
	.notifier_call  = trace_panic_handler,
	.next           = NULL,
	.priority       = 150   /* priority: INT_MAX >= x >= 0 */
};



static int trace_die_handler(struct notifier_block *self,
			     unsigned long val,
			     void *data)
{
	switch (val) {
	case DIE_OOPS:
		if (ftrace_dump_on_oops)
			ftrace_dump(ftrace_dump_on_oops);
		break;
	default:
		break;
	}
	return NOTIFY_OK;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
40
93.02%
3
75.00%
Frédéric Weisbecker
3
6.98%
1
25.00%
Total
43
100.00%
4
100.00%


static struct notifier_block trace_die_notifier = {
	.notifier_call = trace_die_handler,
	.priority = 200
};

/*
 * printk is set to max of 1024, we really don't need it that big.
 * Nothing should be printing 1000 characters anyway.
 */

#define TRACE_MAX_PRINT		1000

/*
 * Define here KERN_TRACE so that we have one place to modify
 * it if we decide to change what log level the ftrace dump
 * should be at.
 */

#define KERN_TRACE		KERN_EMERG


void

trace_printk_seq(struct trace_seq *s)
{
	/* Probably should print a warning here. */
	if (s->seq.len >= TRACE_MAX_PRINT)
		s->seq.len = TRACE_MAX_PRINT;

	/*
         * More paranoid code. Although the buffer size is set to
         * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just
         * an extra layer of protection.
         */
	if (WARN_ON_ONCE(s->seq.len >= s->seq.size))
		s->seq.len = s->seq.size - 1;

	/* should be zero ended, but we are paranoid. */
	s->buffer[s->seq.len] = 0;

	printk(KERN_TRACE "%s", s->buffer);

	trace_seq_init(s);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
88
97.78%
6
85.71%
Jovi Zhangwei
2
2.22%
1
14.29%
Total
90
100.00%
7
100.00%



void trace_init_global_iter(struct trace_iterator *iter)
{
	iter->tr = &global_trace;
	iter->trace = iter->tr->current_trace;
	iter->cpu_file = RING_BUFFER_ALL_CPUS;
	iter->trace_buffer = &global_trace.trace_buffer;

	if (iter->trace && iter->trace->open)
		iter->trace->open(iter);

	/* Annotate start of buffers if we had overruns */
	if (ring_buffer_overruns(iter->trace_buffer->buffer))
		iter->iter_flags |= TRACE_FILE_ANNOTATE;

	/* Output in nanoseconds only if we are using a clock in nanoseconds. */
	if (trace_clocks[iter->tr->clock_id].in_ns)
		iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Cody P Schafer
59
58.42%
1
20.00%
Jason Wessel
29
28.71%
1
20.00%
Steven Rostedt
13
12.87%
3
60.00%
Total
101
100.00%
5
100.00%



void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
{
	/* use static because iter can be a bit big for the stack */
	static struct trace_iterator iter;
	static atomic_t dump_running;
	struct trace_array *tr = &global_trace;
	unsigned int old_userobj;
	unsigned long flags;
	int cnt = 0, cpu;

	/* Only allow one dump user at a time. */
	if (atomic_inc_return(&dump_running) != 1) {
		atomic_dec(&dump_running);
		return;
	}

	/*
         * Always turn off tracing when we dump.
         * We don't need to show trace output of what happens
         * between multiple crashes.
         *
         * If the user does a sysrq-z, then they can re-enable
         * tracing with echo 1 > tracing_on.
         */
	tracing_off();

	local_irq_save(flags);

	/* Simulate the iterator */
	trace_init_global_iter(&iter);

	for_each_tracing_cpu(cpu) {
		atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
	}

	old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ;

	/* don't look at user memory in panic mode */
	tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ;

	switch (oops_dump_mode) {
	case DUMP_ALL:
		iter.cpu_file = RING_BUFFER_ALL_CPUS;
		break;
	case DUMP_ORIG:
		iter.cpu_file = raw_smp_processor_id();
		break;
	case DUMP_NONE:
		goto out_enable;
	default:
		printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n");
		iter.cpu_file = RING_BUFFER_ALL_CPUS;
	}

	printk(KERN_TRACE "Dumping ftrace buffer:\n");

	/* Did function tracer already get disabled? */
	if (ftrace_is_dead()) {
		printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n");
		printk("#          MAY BE MISSING FUNCTION EVENTS\n");
	}

	/*
         * We need to stop all tracing on all CPUS to read the
         * the next buffer. This is a bit expensive, but is
         * not done often. We fill all what we can read,
         * and then release the locks again.
         */

	while (!trace_empty(&iter)) {

		if (!cnt)
			printk(KERN_TRACE "---------------------------------\n");

		cnt++;

		/* reset all but tr, trace, and overruns */
		memset(&iter.seq, 0,
		       sizeof(struct trace_iterator) -
		       offsetof(struct trace_iterator, seq));
		iter.iter_flags |= TRACE_FILE_LAT_FMT;
		iter.pos = -1;

		if (trace_find_next_entry_inc(&iter) != NULL) {
			int ret;

			ret = print_trace_line(&iter);
			if (ret != TRACE_TYPE_NO_CONSUME)
				trace_consume(&iter);
		}
		touch_nmi_watchdog();

		trace_printk_seq(&iter.seq);
	}

	if (!cnt)
		printk(KERN_TRACE "   (ftrace buffer empty)\n");
	else
		printk(KERN_TRACE "---------------------------------\n");

 out_enable:
	tr->trace_flags |= old_userobj;

	for_each_tracing_cpu(cpu) {
		atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
	}
 	atomic_dec(&dump_running);
	local_irq_restore(flags);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
243
68.07%
13
61.90%
Frédéric Weisbecker
84
23.53%
2
9.52%
Lai Jiangshan
11
3.08%
1
4.76%
Jason Wessel
10
2.80%
1
4.76%
Török Edwin
6
1.68%
1
4.76%
Umesh Tiwari
1
0.28%
1
4.76%
Jovi Zhang
1
0.28%
1
4.76%
Ingo Molnar
1
0.28%
1
4.76%
Total
357
100.00%
21
100.00%


EXPORT_SYMBOL_GPL(ftrace_dump);



__init static int tracer_alloc_buffers(void)
{
	int ring_buf_size;
	int ret = -ENOMEM;

	/*
         * Make sure we don't accidently add more trace options
         * than we have bits for.
         */
	BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE);

	if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL))
		goto out;

	if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL))
		goto out_free_buffer_mask;

	/* Only allocate trace_printk buffers if a trace_printk exists */
	if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt)
		/* Must be called before global_trace.buffer is allocated */
		trace_printk_init_buffers();

	/* To save memory, keep the ring buffer size to its minimum */
	if (ring_buffer_expanded)
		ring_buf_size = trace_buf_size;
	else
		ring_buf_size = 1;

	cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
	cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask);

	raw_spin_lock_init(&global_trace.start_lock);

	/*
         * The prepare callbacks allocates some memory for the ring buffer. We
         * don't free the buffer if the if the CPU goes down. If we were to free
         * the buffer, then the user would lose any trace that was in the
         * buffer. The memory will be removed once the "instance" is removed.
         */
	ret = cpuhp_setup_state_multi(CPUHP_TRACE_RB_PREPARE,
				      "trace/RB:preapre", trace_rb_cpu_prepare,
				      NULL);
	if (ret < 0)
		goto out_free_cpumask;
	/* Used for event triggers */
	ret = -ENOMEM;
	temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE);
	if (!temp_buffer)
		goto out_rm_hp_state;

	if (trace_create_savedcmd() < 0)
		goto out_free_temp_buffer;

	/* TODO: make the number of buffers hot pluggable with CPUS */
	if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) {
		printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
		WARN_ON(1);
		goto out_free_savedcmd;
	}

	if (global_trace.buffer_disabled)
		tracing_off();

	if (trace_boot_clock) {
		ret = tracing_set_clock(&global_trace, trace_boot_clock);
		if (ret < 0)
			pr_warn("Trace clock %s not defined, going back to default\n",
				trace_boot_clock);
	}

	/*
         * register_tracer() might reference current_trace, so it
         * needs to be set before we register anything. This is
         * just a bootstrap of current_trace anyway.
         */
	global_trace.current_trace = &nop_trace;

	global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;

	ftrace_init_global_array_ops(&global_trace);

	init_trace_flags_index(&global_trace);

	register_tracer(&nop_trace);

	/* Function tracing may start here (via kernel command line) */
	init_function_trace();

	/* All seems OK, enable tracing */
	tracing_disabled = 0;

	atomic_notifier_chain_register(&panic_notifier_list,
				       &trace_panic_notifier);

	register_die_notifier(&trace_die_notifier);

	global_trace.flags = TRACE_ARRAY_FL_GLOBAL;

	INIT_LIST_HEAD(&global_trace.systems);
	INIT_LIST_HEAD(&global_trace.events);
	list_add(&global_trace.list, &ftrace_trace_arrays);

	apply_trace_boot_options();

	register_snapshot_cmd();

	return 0;

out_free_savedcmd:
	free_saved_cmdlines_buffer(savedcmd);
out_free_temp_buffer:
	ring_buffer_free(temp_buffer);
out_rm_hp_state:
	cpuhp_remove_multi_state(CPUHP_TRACE_RB_PREPARE);
out_free_cpumask:
	free_cpumask_var(global_trace.tracing_cpumask);
out_free_buffer_mask:
	free_cpumask_var(tracing_buffer_mask);
out:
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
235
63.34%
25
71.43%
Rusty Russell
67
18.06%
1
2.86%
Sebastian Andrzej Siewior
31
8.36%
1
2.86%
Yoshihiro Yunomae
18
4.85%
1
2.86%
Alexander Z Lam
6
1.62%
1
2.86%
Dan Carpenter
5
1.35%
1
2.86%
Vaibhav Nagarnaik
4
1.08%
2
5.71%
Frédéric Weisbecker
2
0.54%
1
2.86%
Jiaxing Wang
2
0.54%
1
2.86%
Joe Perches
1
0.27%
1
2.86%
Total
371
100.00%
35
100.00%



void __init early_trace_init(void)
{
	if (tracepoint_printk) {
		tracepoint_print_iter =
			kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL);
		if (WARN_ON(!tracepoint_print_iter))
			tracepoint_printk = 0;
		else
			static_key_enable(&tracepoint_printk_key.key);
	}
	tracer_alloc_buffers();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
51
100.00%
4
100.00%
Total
51
100.00%
4
100.00%



void __init trace_init(void)
{
	trace_event_init();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
11
100.00%
2
100.00%
Total
11
100.00%
2
100.00%



__init static int clear_boot_tracer(void)
{
	/*
         * The default tracer at boot buffer is an init section.
         * This function is called in lateinit. If we did not
         * find the boot tracer, then clear it out, to prevent
         * later registration from accessing the buffer that is
         * about to be freed.
         */
	if (!default_bootup_tracer)
		return 0;

	printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n",
	       default_bootup_tracer);
	default_bootup_tracer = NULL;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%


fs_initcall(tracer_init_tracefs);

late_initcall_sync(clear_boot_tracer);
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
20692
63.57%
311
50.65%
Frédéric Weisbecker
1585
4.87%
32
5.21%
Yoshihiro Yunomae
894
2.75%
4
0.65%
Vaibhav Nagarnaik
811
2.49%
7
1.14%
Ingo Molnar
697
2.14%
19
3.09%
Eduard - Gabriel Munteanu
678
2.08%
2
0.33%
Hiraku Toyooka
597
1.83%
4
0.65%
Jiri Olsa
571
1.75%
7
1.14%
Joel Fernandes
506
1.55%
7
1.14%
Chunyan Zhang
458
1.41%
1
0.16%
Lai Jiangshan
432
1.33%
12
1.95%
Michael Sartain
307
0.94%
1
0.16%
Zhao Lei
306
0.94%
3
0.49%
Tom Zanussi
293
0.90%
19
3.09%
Li Zefan
265
0.81%
14
2.28%
Stanislav Fomichev
259
0.80%
1
0.16%
Oleg Nesterov
249
0.76%
6
0.98%
Pekka Paalanen
206
0.63%
4
0.65%
Peter Zijlstra
203
0.62%
6
0.98%
Alexander Z Lam
193
0.59%
6
0.98%
Masami Hiramatsu
168
0.52%
5
0.81%
Rusty Russell
128
0.39%
2
0.33%
Jiaxing Wang
125
0.38%
3
0.49%
Arnaldo Carvalho de Melo
111
0.34%
7
1.14%
Jeremy Linton
107
0.33%
8
1.30%
Linus Torvalds
93
0.29%
3
0.49%
Arnd Bergmann
77
0.24%
1
0.16%
Tim Bird
77
0.24%
1
0.16%
Thomas Gleixner
76
0.23%
8
1.30%
Avadh Patel
73
0.22%
1
0.16%
Chunyu Hu
69
0.21%
3
0.49%
Jens Axboe
69
0.21%
1
0.16%
Motohiro Kosaki
68
0.21%
2
0.33%
Jovi Zhangwei
68
0.21%
4
0.65%
Török Edwin
67
0.21%
4
0.65%
Soeren Sandmann Pedersen
63
0.19%
1
0.16%
Andrew Lutomirski
61
0.19%
1
0.16%
David Sharp
59
0.18%
4
0.65%
Cody P Schafer
59
0.18%
1
0.16%
Slava Pestov
50
0.15%
2
0.33%
Markus Metzger
48
0.15%
1
0.16%
Jason Wessel
45
0.14%
1
0.16%
Al Viro
39
0.12%
5
0.81%
Namhyung Kim
36
0.11%
7
1.14%
Carsten Emde
33
0.10%
3
0.49%
Bo Yan
32
0.10%
1
0.16%
Mandeep Singh Baines
31
0.10%
1
0.16%
Sebastian Andrzej Siewior
31
0.10%
1
0.16%
Rabin Vincent
27
0.08%
2
0.33%
Ziqian SUN (Zamir)
25
0.08%
1
0.16%
David S. Miller
25
0.08%
1
0.16%
Luis Claudio R. Goncalves
23
0.07%
1
0.16%
Joe Perches
19
0.06%
1
0.16%
Dan Carpenter
17
0.05%
4
0.65%
Geyslan G. Bem
16
0.05%
1
0.16%
Peter Hüwe
16
0.05%
1
0.16%
Eric W. Biedermann
14
0.04%
2
0.33%
Rasmus Villemoes
13
0.04%
2
0.33%
Tejun Heo
12
0.04%
2
0.33%
Hannes Eder
11
0.03%
2
0.33%
Sasha Levin
10
0.03%
1
0.16%
Marcin Ślusarz
10
0.03%
1
0.16%
Chen Gang S
8
0.02%
2
0.33%
Drew Richardson
8
0.02%
1
0.16%
Andrey Vagin
7
0.02%
1
0.16%
Harvey Harrison
7
0.02%
1
0.16%
Shan Wei
7
0.02%
2
0.33%
Eric Dumazet
7
0.02%
1
0.16%
Tahsin Erdogan
6
0.02%
1
0.16%
Anton Blanchard
6
0.02%
1
0.16%
Naveen N. Rao
6
0.02%
2
0.33%
Matthias Kaehlcke
6
0.02%
1
0.16%
Michael Ellerman
5
0.02%
1
0.16%
Pekka J Enberg
5
0.02%
1
0.16%
Heiko Carstens
5
0.02%
1
0.16%
Julia Lawall
5
0.02%
1
0.16%
Anton Vorontsov
5
0.02%
1
0.16%
Borislav Petkov
5
0.02%
1
0.16%
Wei Yongjun
5
0.02%
1
0.16%
Paul E. McKenney
5
0.02%
1
0.16%
Gil Fruchter
3
0.01%
2
0.33%
Clark Williams
3
0.01%
1
0.16%
Amey Telawane
3
0.01%
1
0.16%
David Howells
3
0.01%
1
0.16%
Abhishek Sagar
3
0.01%
1
0.16%
Alexey Dobriyan
3
0.01%
1
0.16%
Wang Tianhong
3
0.01%
1
0.16%
Fabian Frederick
2
0.01%
1
0.16%
Christoph Lameter
2
0.01%
1
0.16%
Dmitri Vorobiev
2
0.01%
1
0.16%
Wang YanQing
2
0.01%
2
0.33%
James Morris
1
0.00%
1
0.16%
Umesh Tiwari
1
0.00%
1
0.16%
Sam Ravnborg
1
0.00%
1
0.16%
Daniel Walter
1
0.00%
1
0.16%
Frans Klaver
1
0.00%
1
0.16%
Lucas De Marchi
1
0.00%
1
0.16%
Pavankumar Kondeti
1
0.00%
1
0.16%
Tony Luck
1
0.00%
1
0.16%
Roel Kluin
1
0.00%
1
0.16%
Jovi Zhang
1
0.00%
1
0.16%
Richard Weinberger
0.00%
0
0.00%
Total
32550
100.00%
614
100.00%
Directory: kernel/trace

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