Release 4.15 kernel/trace/trace_sched_wakeup.c

// SPDX-License-Identifier: GPL-2.0
/*
 * trace task wakeup timings
 *
 * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
 * Copyright (C) 2008 Ingo Molnar <mingo@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/module.h>
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
#include <linux/sched/rt.h>
#include <linux/sched/deadline.h>
#include <trace/events/sched.h>
#include "trace.h"


static struct trace_array	*wakeup_trace;

static int __read_mostly	tracer_enabled;


static struct task_struct	*wakeup_task;

static int			wakeup_cpu;

static int			wakeup_current_cpu;

static unsigned			wakeup_prio = -1;

static int			wakeup_rt;

static int			wakeup_dl;

static int			tracing_dl = 0;


static arch_spinlock_t wakeup_lock =
	(arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;

static void wakeup_reset(struct trace_array *tr);
static void __wakeup_reset(struct trace_array *tr);


static int save_flags;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static int wakeup_display_graph(struct trace_array *tr, int set);

# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH)
#else


static inline int wakeup_display_graph(struct trace_array *tr, int set)
{
	return 0;
}
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# define is_graph(tr) false
#endif


#ifdef CONFIG_FUNCTION_TRACER

static int wakeup_graph_entry(struct ftrace_graph_ent *trace);
static void wakeup_graph_return(struct ftrace_graph_ret *trace);


static bool function_enabled;

/*
 * Prologue for the wakeup function tracers.
 *
 * Returns 1 if it is OK to continue, and preemption
 *            is disabled and data->disabled is incremented.
 *         0 if the trace is to be ignored, and preemption
 *            is not disabled and data->disabled is
 *            kept the same.
 *
 * Note, this function is also used outside this ifdef but
 *  inside the #ifdef of the function graph tracer below.
 *  This is OK, since the function graph tracer is
 *  dependent on the function tracer.
 */

static int

func_prolog_preempt_disable(struct trace_array *tr,
			    struct trace_array_cpu **data,
			    int *pc)
{
	long disabled;
	int cpu;

	if (likely(!wakeup_task))
		return 0;

	*pc = preempt_count();
	preempt_disable_notrace();

	cpu = raw_smp_processor_id();
	if (cpu != wakeup_current_cpu)
		goto out_enable;

	*data = per_cpu_ptr(tr->trace_buffer.data, cpu);
	disabled = atomic_inc_return(&(*data)->disabled);
	if (unlikely(disabled != 1))
		goto out;

	return 1;

out:
	atomic_dec(&(*data)->disabled);

out_enable:
	preempt_enable_notrace();
	return 0;
}

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/*
 * wakeup uses its own tracer function to keep the overhead down:
 */

static void

wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
		   struct ftrace_ops *op, struct pt_regs *pt_regs)
{
	struct trace_array *tr = wakeup_trace;
	struct trace_array_cpu *data;
	unsigned long flags;
	int pc;

	if (!func_prolog_preempt_disable(tr, &data, &pc))
		return;

	local_irq_save(flags);
	trace_function(tr, ip, parent_ip, flags, pc);
	local_irq_restore(flags);

	atomic_dec(&data->disabled);
	preempt_enable_notrace();
}

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static int register_wakeup_function(struct trace_array *tr, int graph, int set)
{
	int ret;

	/* 'set' is set if TRACE_ITER_FUNCTION is about to be set */
	if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION)))
		return 0;

	if (graph)
		ret = register_ftrace_graph(&wakeup_graph_return,
					    &wakeup_graph_entry);
	else
		ret = register_ftrace_function(tr->ops);

	if (!ret)
		function_enabled = true;

	return ret;
}

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static void unregister_wakeup_function(struct trace_array *tr, int graph)
{
	if (!function_enabled)
		return;

	if (graph)
		unregister_ftrace_graph();
	else
		unregister_ftrace_function(tr->ops);

	function_enabled = false;
}

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static int wakeup_function_set(struct trace_array *tr, u32 mask, int set)
{
	if (!(mask & TRACE_ITER_FUNCTION))
		return 0;

	if (set)
		register_wakeup_function(tr, is_graph(tr), 1);
	else
		unregister_wakeup_function(tr, is_graph(tr));
	return 1;
}
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#else


static int register_wakeup_function(struct trace_array *tr, int graph, int set)
{
	return 0;
}
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static void unregister_wakeup_function(struct trace_array *tr, int graph) { }
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static int wakeup_function_set(struct trace_array *tr, u32 mask, int set)
{
	return 0;
}
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#endif /* CONFIG_FUNCTION_TRACER */



static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
{
	struct tracer *tracer = tr->current_trace;

	if (wakeup_function_set(tr, mask, set))
		return 0;

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
	if (mask & TRACE_ITER_DISPLAY_GRAPH)
		return wakeup_display_graph(tr, set);
#endif

	return trace_keep_overwrite(tracer, mask, set);
}

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static int start_func_tracer(struct trace_array *tr, int graph)
{
	int ret;

	ret = register_wakeup_function(tr, graph, 0);

	if (!ret && tracing_is_enabled())
		tracer_enabled = 1;
	else
		tracer_enabled = 0;

	return ret;
}

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static void stop_func_tracer(struct trace_array *tr, int graph)
{
	tracer_enabled = 0;

	unregister_wakeup_function(tr, graph);
}

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#ifdef CONFIG_FUNCTION_GRAPH_TRACER


static int wakeup_display_graph(struct trace_array *tr, int set)
{
	if (!(is_graph(tr) ^ set))
		return 0;

	stop_func_tracer(tr, !set);

	wakeup_reset(wakeup_trace);
	tr->max_latency = 0;

	return start_func_tracer(tr, set);
}

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static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
{
	struct trace_array *tr = wakeup_trace;
	struct trace_array_cpu *data;
	unsigned long flags;
	int pc, ret = 0;

	if (ftrace_graph_ignore_func(trace))
		return 0;
	/*
         * Do not trace a function if it's filtered by set_graph_notrace.
         * Make the index of ret stack negative to indicate that it should
         * ignore further functions.  But it needs its own ret stack entry
         * to recover the original index in order to continue tracing after
         * returning from the function.
         */
	if (ftrace_graph_notrace_addr(trace->func))
		return 1;

	if (!func_prolog_preempt_disable(tr, &data, &pc))
		return 0;

	local_save_flags(flags);
	ret = __trace_graph_entry(tr, trace, flags, pc);
	atomic_dec(&data->disabled);
	preempt_enable_notrace();

	return ret;
}

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static void wakeup_graph_return(struct ftrace_graph_ret *trace)
{
	struct trace_array *tr = wakeup_trace;
	struct trace_array_cpu *data;
	unsigned long flags;
	int pc;

	if (!func_prolog_preempt_disable(tr, &data, &pc))
		return;

	local_save_flags(flags);
	__trace_graph_return(tr, trace, flags, pc);
	atomic_dec(&data->disabled);

	preempt_enable_notrace();
	return;
}

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static void wakeup_trace_open(struct trace_iterator *iter)
{
	if (is_graph(iter->tr))
		graph_trace_open(iter);
}

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static void wakeup_trace_close(struct trace_iterator *iter)
{
	if (iter->private)
		graph_trace_close(iter);
}

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#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \
                            TRACE_GRAPH_PRINT_ABS_TIME | \
                            TRACE_GRAPH_PRINT_DURATION)



static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
{
	/*
         * In graph mode call the graph tracer output function,
         * otherwise go with the TRACE_FN event handler
         */
	if (is_graph(iter->tr))
		return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS);

	return TRACE_TYPE_UNHANDLED;
}

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static void wakeup_print_header(struct seq_file *s)
{
	if (is_graph(wakeup_trace))
		print_graph_headers_flags(s, GRAPH_TRACER_FLAGS);
	else
		trace_default_header(s);
}

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static void

__trace_function(struct trace_array *tr,
		 unsigned long ip, unsigned long parent_ip,
		 unsigned long flags, int pc)
{
	if (is_graph(tr))
		trace_graph_function(tr, ip, parent_ip, flags, pc);
	else
		trace_function(tr, ip, parent_ip, flags, pc);
}
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#else

#define __trace_function trace_function



static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
{
	return TRACE_TYPE_UNHANDLED;
}

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static void wakeup_trace_open(struct trace_iterator *iter) { }
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static void wakeup_trace_close(struct trace_iterator *iter) { }

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#ifdef CONFIG_FUNCTION_TRACER


static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
{
	return -1;
}
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static void wakeup_graph_return(struct ftrace_graph_ret *trace) { }
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static void wakeup_print_header(struct seq_file *s)
{
	trace_default_header(s);
}
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#else


static void wakeup_print_header(struct seq_file *s)
{
	trace_latency_header(s);
}
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#endif /* CONFIG_FUNCTION_TRACER */
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

/*
 * Should this new latency be reported/recorded?
 */


static bool report_latency(struct trace_array *tr, u64 delta)
{
	if (tracing_thresh) {
		if (delta < tracing_thresh)
			return false;
	} else {
		if (delta <= tr->max_latency)
			return false;
	}
	return true;
}

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static void

probe_wakeup_migrate_task(void *ignore, struct task_struct *task, int cpu)
{
	if (task != wakeup_task)
		return;

	wakeup_current_cpu = cpu;
}

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static void

tracing_sched_switch_trace(struct trace_array *tr,
			   struct task_struct *prev,
			   struct task_struct *next,
			   unsigned long flags, int pc)
{
	struct trace_event_call *call = &event_context_switch;
	struct ring_buffer *buffer = tr->trace_buffer.buffer;
	struct ring_buffer_event *event;
	struct ctx_switch_entry *entry;

	event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
					  sizeof(*entry), flags, pc);
	if (!event)
		return;
	entry	= ring_buffer_event_data(event);
	entry->prev_pid			= prev->pid;
	entry->prev_prio		= prev->prio;
	entry->prev_state		= task_state_index(prev);
	entry->next_pid			= next->pid;
	entry->next_prio		= next->prio;
	entry->next_state		= task_state_index(next);
	entry->next_cpu	= task_cpu(next);

	if (!call_filter_check_discard(call, entry, buffer, event))
		trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
}

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static void

tracing_sched_wakeup_trace(struct trace_array *tr,
			   struct task_struct *wakee,
			   struct task_struct *curr,
			   unsigned long flags, int pc)
{
	struct trace_event_call *call = &event_wakeup;
	struct ring_buffer_event *event;
	struct ctx_switch_entry *entry;
	struct ring_buffer *buffer = tr->trace_buffer.buffer;

	event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
					  sizeof(*entry), flags, pc);
	if (!event)
		return;
	entry	= ring_buffer_event_data(event);
	entry->prev_pid			= curr->pid;
	entry->prev_prio		= curr->prio;
	entry->prev_state		= task_state_index(curr);
	entry->next_pid			= wakee->pid;
	entry->next_prio		= wakee->prio;
	entry->next_state		= task_state_index(wakee);
	entry->next_cpu			= task_cpu(wakee);

	if (!call_filter_check_discard(call, entry, buffer, event))
		trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
}

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static void notrace

probe_wakeup_sched_switch(void *ignore, bool preempt,
			  struct task_struct *prev, struct task_struct *next)
{
	struct trace_array_cpu *data;
	u64 T0, T1, delta;
	unsigned long flags;
	long disabled;
	int cpu;
	int pc;

	tracing_record_cmdline(prev);

	if (unlikely(!tracer_enabled))
		return;

	/*
         * When we start a new trace, we set wakeup_task to NULL
         * and then set tracer_enabled = 1. We want to make sure
         * that another CPU does not see the tracer_enabled = 1
         * and the wakeup_task with an older task, that might
         * actually be the same as next.
         */
	smp_rmb();

	if (next != wakeup_task)
		return;

	pc = preempt_count();

	/* disable local data, not wakeup_cpu data */
	cpu = raw_smp_processor_id();
	disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
	if (likely(disabled != 1))
		goto out;

	local_irq_save(flags);
	arch_spin_lock(&wakeup_lock);

	/* We could race with grabbing wakeup_lock */
	if (unlikely(!tracer_enabled || next != wakeup_task))
		goto out_unlock;

	/* The task we are waiting for is waking up */
	data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu);

	__trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
	tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);

	T0 = data->preempt_timestamp;
	T1 = ftrace_now(cpu);
	delta = T1-T0;

	if (!report_latency(wakeup_trace, delta))
		goto out_unlock;

	if (likely(!is_tracing_stopped())) {
		wakeup_trace->max_latency = delta;
		update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
	}

out_unlock:
	__wakeup_reset(wakeup_trace);
	arch_spin_unlock(&wakeup_lock);
	local_irq_restore(flags);
out:
	atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
}

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static void __wakeup_reset(struct trace_array *tr)
{
	wakeup_cpu = -1;
	wakeup_prio = -1;
	tracing_dl = 0;

	if (wakeup_task)
		put_task_struct(wakeup_task);

	wakeup_task = NULL;
}

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static void wakeup_reset(struct trace_array *tr)
{
	unsigned long flags;

	tracing_reset_online_cpus(&tr->trace_buffer);

	local_irq_save(flags);
	arch_spin_lock(&wakeup_lock);
	__wakeup_reset(tr);
	arch_spin_unlock(&wakeup_lock);
	local_irq_restore(flags);
}

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static void

probe_wakeup(void *ignore, struct task_struct *p)
{
	struct trace_array_cpu *data;
	int cpu = smp_processor_id();
	unsigned long flags;
	long disabled;
	int pc;

	if (likely(!tracer_enabled))
		return;

	tracing_record_cmdline(p);
	tracing_record_cmdline(current);

	/*
         * Semantic is like this:
         *  - wakeup tracer handles all tasks in the system, independently
         *    from their scheduling class;
         *  - wakeup_rt tracer handles tasks belonging to sched_dl and
         *    sched_rt class;
         *  - wakeup_dl handles tasks belonging to sched_dl class only.
         */
	if (tracing_dl || (wakeup_dl && !dl_task(p)) ||
	    (wakeup_rt && !dl_task(p) && !rt_task(p)) ||
	    (!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio)))
		return;

	pc = preempt_count();
	disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
	if (unlikely(disabled != 1))
		goto out;

	/* interrupts should be off from try_to_wake_up */
	arch_spin_lock(&wakeup_lock);

	/* check for races. */
	if (!tracer_enabled || tracing_dl ||
	    (!dl_task(p) && p->prio >= wakeup_prio))
		goto out_locked;

	/* reset the trace */
	__wakeup_reset(wakeup_trace);

	wakeup_cpu = task_cpu(p);
	wakeup_current_cpu = wakeup_cpu;
	wakeup_prio = p->prio;

	/*
         * Once you start tracing a -deadline task, don't bother tracing
         * another task until the first one wakes up.
         */
	if (dl_task(p))
		tracing_dl = 1;
	else
		tracing_dl = 0;

	wakeup_task = p;
	get_task_struct(wakeup_task);

	local_save_flags(flags);

	data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu);
	data->preempt_timestamp = ftrace_now(cpu);
	tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);

	/*
         * We must be careful in using CALLER_ADDR2. But since wake_up
         * is not called by an assembly function  (where as schedule is)
         * it should be safe to use it here.
         */
	__trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);

out_locked:
	arch_spin_unlock(&wakeup_lock);
out:
	atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
224
72.49%
9
64.29%
Dario Faggioli
56
18.12%
1
7.14%
Mathieu Desnoyers
25
8.09%
1
7.14%
Thomas Gleixner
2
0.65%
1
7.14%
Jiri Olsa
1
0.32%
1
7.14%
Ingo Molnar
1
0.32%
1
7.14%
Total
309
100.00%
14
100.00%



static void start_wakeup_tracer(struct trace_array *tr)
{
	int ret;

	ret = register_trace_sched_wakeup(probe_wakeup, NULL);
	if (ret) {
		pr_info("wakeup trace: Couldn't activate tracepoint"
			" probe to kernel_sched_wakeup\n");
		return;
	}

	ret = register_trace_sched_wakeup_new(probe_wakeup, NULL);
	if (ret) {
		pr_info("wakeup trace: Couldn't activate tracepoint"
			" probe to kernel_sched_wakeup_new\n");
		goto fail_deprobe;
	}

	ret = register_trace_sched_switch(probe_wakeup_sched_switch, NULL);
	if (ret) {
		pr_info("sched trace: Couldn't activate tracepoint"
			" probe to kernel_sched_switch\n");
		goto fail_deprobe_wake_new;
	}

	ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
	if (ret) {
		pr_info("wakeup trace: Couldn't activate tracepoint"
			" probe to kernel_sched_migrate_task\n");
		return;
	}

	wakeup_reset(tr);

	/*
         * Don't let the tracer_enabled = 1 show up before
         * the wakeup_task is reset. This may be overkill since
         * wakeup_reset does a spin_unlock after setting the
         * wakeup_task to NULL, but I want to be safe.
         * This is a slow path anyway.
         */
	smp_wmb();

	if (start_func_tracer(tr, is_graph(tr)))
		printk(KERN_ERR "failed to start wakeup tracer\n");

	return;
fail_deprobe_wake_new:
	unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
fail_deprobe:
	unregister_trace_sched_wakeup(probe_wakeup, NULL);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mathieu Desnoyers
80
52.63%
2
20.00%
Steven Rostedt
62
40.79%
6
60.00%
Jiri Olsa
9
5.92%
1
10.00%
Wenji Huang
1
0.66%
1
10.00%
Total
152
100.00%
10
100.00%



static void stop_wakeup_tracer(struct trace_array *tr)
{
	tracer_enabled = 0;
	stop_func_tracer(tr, is_graph(tr));
	unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
	unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
	unregister_trace_sched_wakeup(probe_wakeup, NULL);
	unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
36
67.92%
6
66.67%
Mathieu Desnoyers
15
28.30%
2
22.22%
Jiri Olsa
2
3.77%
1
11.11%
Total
53
100.00%
9
100.00%


static bool wakeup_busy;



static int __wakeup_tracer_init(struct trace_array *tr)
{
	save_flags = tr->trace_flags;

	/* non overwrite screws up the latency tracers */
	set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
	set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);

	tr->max_latency = 0;
	wakeup_trace = tr;
	ftrace_init_array_ops(tr, wakeup_tracer_call);
	start_wakeup_tracer(tr);

	wakeup_busy = true;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
61
93.85%
10
90.91%
Frédéric Weisbecker
4
6.15%
1
9.09%
Total
65
100.00%
11
100.00%



static int wakeup_tracer_init(struct trace_array *tr)
{
	if (wakeup_busy)
		return -EBUSY;

	wakeup_dl = 0;
	wakeup_rt = 0;
	return __wakeup_tracer_init(tr);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
29
87.88%
2
66.67%
Dario Faggioli
4
12.12%
1
33.33%
Total
33
100.00%
3
100.00%



static int wakeup_rt_tracer_init(struct trace_array *tr)
{
	if (wakeup_busy)
		return -EBUSY;

	wakeup_dl = 0;
	wakeup_rt = 1;
	return __wakeup_tracer_init(tr);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
29
87.88%
2
66.67%
Dario Faggioli
4
12.12%
1
33.33%
Total
33
100.00%
3
100.00%



static int wakeup_dl_tracer_init(struct trace_array *tr)
{
	if (wakeup_busy)
		return -EBUSY;

	wakeup_dl = 1;
	wakeup_rt = 0;
	return __wakeup_tracer_init(tr);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Dario Faggioli
25
75.76%
1
50.00%
Steven Rostedt
8
24.24%
1
50.00%
Total
33
100.00%
2
100.00%



static void wakeup_tracer_reset(struct trace_array *tr)
{
	int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT;
	int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE;

	stop_wakeup_tracer(tr);
	/* make sure we put back any tasks we are tracing */
	wakeup_reset(tr);

	set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
	set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
	ftrace_reset_array_ops(tr);
	wakeup_busy = false;
}

Contributors
Person
Tokens
Prop
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CommitProp
Steven Rostedt
63
100.00%
6
100.00%
Total
63
100.00%
6
100.00%



static void wakeup_tracer_start(struct trace_array *tr)
{
	wakeup_reset(tr);
	tracer_enabled = 1;
}

Contributors
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Steven Rostedt
20
100.00%
1
100.00%
Total
20
100.00%
1
100.00%



static void wakeup_tracer_stop(struct trace_array *tr)
{
	tracer_enabled = 0;
}

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Steven Rostedt
15
100.00%
2
100.00%
Total
15
100.00%
2
100.00%


static struct tracer wakeup_tracer __read_mostly =
{
	.name		= "wakeup",
	.init		= wakeup_tracer_init,
	.reset		= wakeup_tracer_reset,
	.start		= wakeup_tracer_start,
	.stop		= wakeup_tracer_stop,
	.print_max	= true,
	.print_header	= wakeup_print_header,
	.print_line	= wakeup_print_line,
	.flag_changed	= wakeup_flag_changed,
#ifdef CONFIG_FTRACE_SELFTEST
	.selftest    = trace_selftest_startup_wakeup,
#endif
	.open		= wakeup_trace_open,
	.close		= wakeup_trace_close,
	.allow_instances = true,
	.use_max_tr	= true,
};


static struct tracer wakeup_rt_tracer __read_mostly =
{
	.name		= "wakeup_rt",
	.init		= wakeup_rt_tracer_init,
	.reset		= wakeup_tracer_reset,
	.start		= wakeup_tracer_start,
	.stop		= wakeup_tracer_stop,
	.print_max	= true,
	.print_header	= wakeup_print_header,
	.print_line	= wakeup_print_line,
	.flag_changed	= wakeup_flag_changed,
#ifdef CONFIG_FTRACE_SELFTEST
	.selftest    = trace_selftest_startup_wakeup,
#endif
	.open		= wakeup_trace_open,
	.close		= wakeup_trace_close,
	.allow_instances = true,
	.use_max_tr	= true,
};


static struct tracer wakeup_dl_tracer __read_mostly =
{
	.name		= "wakeup_dl",
	.init		= wakeup_dl_tracer_init,
	.reset		= wakeup_tracer_reset,
	.start		= wakeup_tracer_start,
	.stop		= wakeup_tracer_stop,
	.print_max	= true,
	.print_header	= wakeup_print_header,
	.print_line	= wakeup_print_line,
	.flag_changed	= wakeup_flag_changed,
#ifdef CONFIG_FTRACE_SELFTEST
	.selftest    = trace_selftest_startup_wakeup,
#endif
	.open		= wakeup_trace_open,
	.close		= wakeup_trace_close,
	.allow_instances = true,
	.use_max_tr	= true,
};



__init static int init_wakeup_tracer(void)
{
	int ret;

	ret = register_tracer(&wakeup_tracer);
	if (ret)
		return ret;

	ret = register_tracer(&wakeup_rt_tracer);
	if (ret)
		return ret;

	ret = register_tracer(&wakeup_dl_tracer);
	if (ret)
		return ret;

	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
45
75.00%
2
66.67%
Dario Faggioli
15
25.00%
1
33.33%
Total
60
100.00%
3
100.00%


core_initcall(init_wakeup_tracer);
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
2163
67.87%
40
61.54%
Jiri Olsa
619
19.42%
3
4.62%
Dario Faggioli
199
6.24%
2
3.08%
Mathieu Desnoyers
136
4.27%
2
3.08%
Peter Zijlstra
15
0.47%
3
4.62%
Thomas Gleixner
11
0.35%
4
6.15%
Carsten Emde
11
0.35%
1
1.54%
Motohiro Kosaki
8
0.25%
1
1.54%
Zhou Chengming
5
0.16%
1
1.54%
Frédéric Weisbecker
4
0.13%
1
1.54%
Hiraku Toyooka
4
0.13%
1
1.54%
Yaowei Bai
4
0.13%
1
1.54%
Clark Williams
3
0.09%
1
1.54%
Ingo Molnar
2
0.06%
1
1.54%
Wenji Huang
1
0.03%
1
1.54%
Nadia Yvette Chambers
1
0.03%
1
1.54%
Greg Kroah-Hartman
1
0.03%
1
1.54%
Total
3187
100.00%
65
100.00%
Directory: kernel/trace

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