Release 4.15 kernel/trace/trace_probe.c

/*
 * Common code for probe-based Dynamic events.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * This code was copied from kernel/trace/trace_kprobe.c written by
 * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
 *
 * Updates to make this generic:
 * Copyright (C) IBM Corporation, 2010-2011
 * Author:     Srikar Dronamraju
 */

#define pr_fmt(fmt)	"trace_probe: " fmt

#include "trace_probe.h"


const char *reserved_field_names[] = {
	"common_type",
	"common_flags",
	"common_preempt_count",
	"common_pid",
	"common_tgid",
	FIELD_STRING_IP,
	FIELD_STRING_RETIP,
	FIELD_STRING_FUNC,
};

/* Printing  in basic type function template */

#define DEFINE_BASIC_PRINT_TYPE_FUNC(tname, type, fmt)			\
int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, const char *name,  \
                                void *data, void *ent)                  \
{                                                                       \
        trace_seq_printf(s, " %s=" fmt, name, *(type *)data);           \
        return !trace_seq_has_overflowed(s);                            \
}                                                                       \
const char PRINT_TYPE_FMT_NAME(tname)[] = fmt;                          \
NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(tname));

DEFINE_BASIC_PRINT_TYPE_FUNC(u8,  u8,  "%u")
DEFINE_BASIC_PRINT_TYPE_FUNC(u16, u16, "%u")
DEFINE_BASIC_PRINT_TYPE_FUNC(u32, u32, "%u")
DEFINE_BASIC_PRINT_TYPE_FUNC(u64, u64, "%Lu")
DEFINE_BASIC_PRINT_TYPE_FUNC(s8,  s8,  "%d")
DEFINE_BASIC_PRINT_TYPE_FUNC(s16, s16, "%d")
DEFINE_BASIC_PRINT_TYPE_FUNC(s32, s32, "%d")
DEFINE_BASIC_PRINT_TYPE_FUNC(s64, s64, "%Ld")
DEFINE_BASIC_PRINT_TYPE_FUNC(x8,  u8,  "0x%x")
DEFINE_BASIC_PRINT_TYPE_FUNC(x16, u16, "0x%x")
DEFINE_BASIC_PRINT_TYPE_FUNC(x32, u32, "0x%x")
DEFINE_BASIC_PRINT_TYPE_FUNC(x64, u64, "0x%Lx")

/* Print type function for string type */


int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name,
				 void *data, void *ent)
{
	int len = *(u32 *)data >> 16;

	if (!len)
		trace_seq_printf(s, " %s=(fault)", name);
	else
		trace_seq_printf(s, " %s=\"%s\"", name,
				 (const char *)get_loc_data(data, ent));
	return !trace_seq_has_overflowed(s);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
73
90.12%
1
50.00%
Steven Rostedt
8
9.88%
1
50.00%
Total
81
100.00%
2
100.00%

NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(string));

const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";


#define CHECK_FETCH_FUNCS(method, fn)			\
	(((FETCH_FUNC_NAME(method, u8) == fn) ||        \
          (FETCH_FUNC_NAME(method, u16) == fn) ||       \
          (FETCH_FUNC_NAME(method, u32) == fn) ||       \
          (FETCH_FUNC_NAME(method, u64) == fn) ||       \
          (FETCH_FUNC_NAME(method, string) == fn) ||    \
          (FETCH_FUNC_NAME(method, string_size) == fn)) \
         && (fn != NULL))

/* Data fetch function templates */

#define DEFINE_FETCH_reg(type)						\
void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, void *offset, void *dest) \
{                                                                       \
        *(type *)dest = (type)regs_get_register(regs,                   \
                                (unsigned int)((unsigned long)offset)); \
}                                                                       \
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(reg, type));

DEFINE_BASIC_FETCH_FUNCS(reg)
/* No string on the register */

#define fetch_reg_string	NULL

#define fetch_reg_string_size	NULL


#define DEFINE_FETCH_retval(type)					\
void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,                \
                                   void *dummy, void *dest)             \
{                                                                       \
        *(type *)dest = (type)regs_return_value(regs);                  \
}                                                                       \
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(retval, type));
DEFINE_BASIC_FETCH_FUNCS(retval)
/* No string on the retval */

#define fetch_retval_string		NULL

#define fetch_retval_string_size	NULL

/* Dereference memory access function */
struct deref_fetch_param {
	struct fetch_param	orig;
	long			offset;
	fetch_func_t		fetch;
	fetch_func_t		fetch_size;
};


#define DEFINE_FETCH_deref(type)					\
void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,                 \
                                  void *data, void *dest)               \
{                                                                       \
        struct deref_fetch_param *dprm = data;                          \
        unsigned long addr;                                             \
        call_fetch(&dprm->orig, regs, &addr);                           \
        if (addr) {                                                     \
                addr += dprm->offset;                                   \
                dprm->fetch(regs, (void *)addr, dest);                  \
        } else                                                          \
                *(type *)dest = 0;                                      \
}                                                                       \
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(deref, type));

DEFINE_BASIC_FETCH_FUNCS(deref)
DEFINE_FETCH_deref(string)

void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs,
					 void *data, void *dest)
{
	struct deref_fetch_param *dprm = data;
	unsigned long addr;

	call_fetch(&dprm->orig, regs, &addr);
	if (addr && dprm->fetch_size) {
		addr += dprm->offset;
		dprm->fetch_size(regs, (void *)addr, dest);
	} else
		*(string_size *)dest = 0;
}
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(deref, string_size));



static void update_deref_fetch_param(struct deref_fetch_param *data)
{
	if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
		update_deref_fetch_param(data->orig.data);
	else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
		update_symbol_cache(data->orig.data);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
56
100.00%
1
100.00%
Total
56
100.00%
1
100.00%


NOKPROBE_SYMBOL(update_deref_fetch_param);



static void free_deref_fetch_param(struct deref_fetch_param *data)
{
	if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
		free_deref_fetch_param(data->orig.data);
	else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
		free_symbol_cache(data->orig.data);
	kfree(data);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
61
100.00%
1
100.00%
Total
61
100.00%
1
100.00%


NOKPROBE_SYMBOL(free_deref_fetch_param);

/* Bitfield fetch function */

struct bitfield_fetch_param {
	
struct fetch_param	orig;
	
unsigned char		hi_shift;
	
unsigned char		low_shift;
};


#define DEFINE_FETCH_bitfield(type)					\
void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,              \
                                     void *data, void *dest)            \
{                                                                       \
        struct bitfield_fetch_param *bprm = data;                       \
        type buf = 0;                                                   \
        call_fetch(&bprm->orig, regs, &buf);                            \
        if (buf) {                                                      \
                buf <<= bprm->hi_shift;                                 \
                buf >>= bprm->low_shift;                                \
        }                                                               \
        *(type *)dest = buf;                                            \
}                                                                       \
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(bitfield, type));
DEFINE_BASIC_FETCH_FUNCS(bitfield)

#define fetch_bitfield_string		NULL

#define fetch_bitfield_string_size	NULL


static void

update_bitfield_fetch_param(struct bitfield_fetch_param *data)
{
	/*
         * Don't check the bitfield itself, because this must be the
         * last fetch function.
         */
	if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
		update_deref_fetch_param(data->orig.data);
	else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
		update_symbol_cache(data->orig.data);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
57
100.00%
1
100.00%
Total
57
100.00%
1
100.00%


static void

free_bitfield_fetch_param(struct bitfield_fetch_param *data)
{
	/*
         * Don't check the bitfield itself, because this must be the
         * last fetch function.
         */
	if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
		free_deref_fetch_param(data->orig.data);
	else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
		free_symbol_cache(data->orig.data);

	kfree(data);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
62
100.00%
1
100.00%
Total
62
100.00%
1
100.00%


void FETCH_FUNC_NAME(comm, string)(struct pt_regs *regs,
					  void *data, void *dest)
{
	int maxlen = get_rloc_len(*(u32 *)dest);
	u8 *dst = get_rloc_data(dest);
	long ret;

	if (!maxlen)
		return;

	ret = strlcpy(dst, current->comm, maxlen);
	*(u32 *)dest = make_data_rloc(ret, get_rloc_offs(*(u32 *)dest));
}
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(comm, string));


void FETCH_FUNC_NAME(comm, string_size)(struct pt_regs *regs,
					       void *data, void *dest)
{
	*(u32 *)dest = strlen(current->comm) + 1;
}
NOKPROBE_SYMBOL(FETCH_FUNC_NAME(comm, string_size));



static const struct fetch_type *find_fetch_type(const char *type,
						const struct fetch_type *ftbl)
{
	int i;

	if (!type)
		type = DEFAULT_FETCH_TYPE_STR;

	/* Special case: bitfield */
	if (*type == 'b') {
		unsigned long bs;

		type = strchr(type, '/');
		if (!type)
			goto fail;

		type++;
		if (kstrtoul(type, 0, &bs))
			goto fail;

		switch (bs) {
		case 8:
			return find_fetch_type("u8", ftbl);
		case 16:
			return find_fetch_type("u16", ftbl);
		case 32:
			return find_fetch_type("u32", ftbl);
		case 64:
			return find_fetch_type("u64", ftbl);
		default:
			goto fail;
		}
	}

	for (i = 0; ftbl[i].name; i++) {
		if (strcmp(type, ftbl[i].name) == 0)
			return &ftbl[i];
	}

fail:
	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
157
86.74%
1
33.33%
Namhyung Kim
23
12.71%
1
33.33%
Daniel Walter
1
0.55%
1
33.33%
Total
181
100.00%
3
100.00%

/* Special function : only accept unsigned long */


static void fetch_kernel_stack_address(struct pt_regs *regs, void *dummy, void *dest)
{
	*(unsigned long *)dest = kernel_stack_pointer(regs);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
31
96.88%
1
50.00%
Namhyung Kim
1
3.12%
1
50.00%
Total
32
100.00%
2
100.00%


NOKPROBE_SYMBOL(fetch_kernel_stack_address);



static void fetch_user_stack_address(struct pt_regs *regs, void *dummy, void *dest)
{
	*(unsigned long *)dest = user_stack_pointer(regs);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Namhyung Kim
32
100.00%
1
100.00%
Total
32
100.00%
1
100.00%


NOKPROBE_SYMBOL(fetch_user_stack_address);



static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
					    fetch_func_t orig_fn,
					    const struct fetch_type *ftbl)
{
	int i;

	if (type != &ftbl[FETCH_TYPE_STRING])
		return NULL;	/* Only string type needs size function */

	for (i = 0; i < FETCH_MTD_END; i++)
		if (type->fetch[i] == orig_fn)
			return ftbl[FETCH_TYPE_STRSIZE].fetch[i];

	WARN_ON(1);	/* This should not happen */

	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
74
90.24%
1
50.00%
Namhyung Kim
8
9.76%
1
50.00%
Total
82
100.00%
2
100.00%

/* Split symbol and offset. */


int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset)
{
	char *tmp;
	int ret;

	if (!offset)
		return -EINVAL;

	tmp = strchr(symbol, '+');
	if (tmp) {
		/* skip sign because kstrtoul doesn't accept '+' */
		ret = kstrtoul(tmp + 1, 0, offset);
		if (ret)
			return ret;

		*tmp = '\0';
	} else
		*offset = 0;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
78
97.50%
1
50.00%
Daniel Walter
2
2.50%
1
50.00%
Total
80
100.00%
2
100.00%


#define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))



static int parse_probe_vars(char *arg, const struct fetch_type *t,
			    struct fetch_param *f, bool is_return,
			    bool is_kprobe)
{
	int ret = 0;
	unsigned long param;

	if (strcmp(arg, "retval") == 0) {
		if (is_return)
			f->fn = t->fetch[FETCH_MTD_retval];
		else
			ret = -EINVAL;
	} else if (strncmp(arg, "stack", 5) == 0) {
		if (arg[5] == '\0') {
			if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR))
				return -EINVAL;

			if (is_kprobe)
				f->fn = fetch_kernel_stack_address;
			else
				f->fn = fetch_user_stack_address;
		} else if (isdigit(arg[5])) {
			ret = kstrtoul(arg + 5, 10, &param);
			if (ret || (is_kprobe && param > PARAM_MAX_STACK))
				ret = -EINVAL;
			else {
				f->fn = t->fetch[FETCH_MTD_stack];
				f->data = (void *)param;
			}
		} else
			ret = -EINVAL;
	} else if (strcmp(arg, "comm") == 0) {
		if (strcmp(t->name, "string") != 0 &&
		    strcmp(t->name, "string_size") != 0)
			return -EINVAL;
		f->fn = t->fetch[FETCH_MTD_comm];
	} else
		ret = -EINVAL;

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
191
72.08%
1
25.00%
Omar Sandoval
53
20.00%
1
25.00%
Namhyung Kim
20
7.55%
1
25.00%
Daniel Walter
1
0.38%
1
25.00%
Total
265
100.00%
4
100.00%

/* Recursive argument parser */


static int parse_probe_arg(char *arg, const struct fetch_type *t,
		     struct fetch_param *f, bool is_return, bool is_kprobe,
		     const struct fetch_type *ftbl)
{
	unsigned long param;
	long offset;
	char *tmp;
	int ret = 0;

	switch (arg[0]) {
	case '$':
		ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe);
		break;

	case '%':	/* named register */
		ret = regs_query_register_offset(arg + 1);
		if (ret >= 0) {
			f->fn = t->fetch[FETCH_MTD_reg];
			f->data = (void *)(unsigned long)ret;
			ret = 0;
		}
		break;

	case '@':	/* memory, file-offset or symbol */
		if (isdigit(arg[1])) {
			ret = kstrtoul(arg + 1, 0, &param);
			if (ret)
				break;

			f->fn = t->fetch[FETCH_MTD_memory];
			f->data = (void *)param;
		} else if (arg[1] == '+') {
			/* kprobes don't support file offsets */
			if (is_kprobe)
				return -EINVAL;

			ret = kstrtol(arg + 2, 0, &offset);
			if (ret)
				break;

			f->fn = t->fetch[FETCH_MTD_file_offset];
			f->data = (void *)offset;
		} else {
			/* uprobes don't support symbols */
			if (!is_kprobe)
				return -EINVAL;

			ret = traceprobe_split_symbol_offset(arg + 1, &offset);
			if (ret)
				break;

			f->data = alloc_symbol_cache(arg + 1, offset);
			if (f->data)
				f->fn = t->fetch[FETCH_MTD_symbol];
		}
		break;

	case '+':	/* deref memory */
		arg++;	/* Skip '+', because kstrtol() rejects it. */
	case '-':
		tmp = strchr(arg, '(');
		if (!tmp)
			break;

		*tmp = '\0';
		ret = kstrtol(arg, 0, &offset);

		if (ret)
			break;

		arg = tmp + 1;
		tmp = strrchr(arg, ')');

		if (tmp) {
			struct deref_fetch_param	*dprm;
			const struct fetch_type		*t2;

			t2 = find_fetch_type(NULL, ftbl);
			*tmp = '\0';
			dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL);

			if (!dprm)
				return -ENOMEM;

			dprm->offset = offset;
			dprm->fetch = t->fetch[FETCH_MTD_memory];
			dprm->fetch_size = get_fetch_size_function(t,
							dprm->fetch, ftbl);
			ret = parse_probe_arg(arg, t2, &dprm->orig, is_return,
							is_kprobe, ftbl);
			if (ret)
				kfree(dprm);
			else {
				f->fn = t->fetch[FETCH_MTD_deref];
				f->data = (void *)dprm;
			}
		}
		break;
	}
	if (!ret && !f->fn) {	/* Parsed, but do not find fetch method */
		pr_info("%s type has no corresponding fetch method.\n", t->name);
		ret = -EINVAL;
	}

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
423
78.33%
2
25.00%
Namhyung Kim
83
15.37%
3
37.50%
Hyeoncheol Lee
26
4.81%
1
12.50%
Stephen Rothwell
5
0.93%
1
12.50%
Daniel Walter
3
0.56%
1
12.50%
Total
540
100.00%
8
100.00%


#define BYTES_TO_BITS(nb)	((BITS_PER_LONG * (nb)) / sizeof(long))

/* Bitfield type needs to be parsed into a fetch function */


static int __parse_bitfield_probe_arg(const char *bf,
				      const struct fetch_type *t,
				      struct fetch_param *f)
{
	struct bitfield_fetch_param *bprm;
	unsigned long bw, bo;
	char *tail;

	if (*bf != 'b')
		return 0;

	bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
	if (!bprm)
		return -ENOMEM;

	bprm->orig = *f;
	f->fn = t->fetch[FETCH_MTD_bitfield];
	f->data = (void *)bprm;
	bw = simple_strtoul(bf + 1, &tail, 0);	/* Use simple one */

	if (bw == 0 || *tail != '@')
		return -EINVAL;

	bf = tail + 1;
	bo = simple_strtoul(bf, &tail, 0);

	if (tail == bf || *tail != '/')
		return -EINVAL;

	bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
	bprm->low_shift = bprm->hi_shift + bo;

	return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
208
100.00%
1
100.00%
Total
208
100.00%
1
100.00%

/* String length checking wrapper */


int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
		struct probe_arg *parg, bool is_return, bool is_kprobe,
		const struct fetch_type *ftbl)
{
	const char *t;
	int ret;

	if (strlen(arg) > MAX_ARGSTR_LEN) {
		pr_info("Argument is too long.: %s\n",  arg);
		return -ENOSPC;
	}
	parg->comm = kstrdup(arg, GFP_KERNEL);
	if (!parg->comm) {
		pr_info("Failed to allocate memory for command '%s'.\n", arg);
		return -ENOMEM;
	}
	t = strchr(parg->comm, ':');
	if (t) {
		arg[t - parg->comm] = '\0';
		t++;
	}
	/*
         * The default type of $comm should be "string", and it can't be
         * dereferenced.
         */
	if (!t && strcmp(arg, "$comm") == 0)
		t = "string";
	parg->type = find_fetch_type(t, ftbl);
	if (!parg->type) {
		pr_info("Unsupported type: %s\n", t);
		return -EINVAL;
	}
	parg->offset = *size;
	*size += parg->type->size;
	ret = parse_probe_arg(arg, parg->type, &parg->fetch, is_return,
			      is_kprobe, ftbl);

	if (ret >= 0 && t != NULL)
		ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);

	if (ret >= 0) {
		parg->fetch_size.fn = get_fetch_size_function(parg->type,
							      parg->fetch.fn,
							      ftbl);
		parg->fetch_size.data = parg->fetch.data;
	}

	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
247
88.21%
2
40.00%
Omar Sandoval
19
6.79%
1
20.00%
Namhyung Kim
9
3.21%
1
20.00%
Stephen Rothwell
5
1.79%
1
20.00%
Total
280
100.00%
5
100.00%

/* Return 1 if name is reserved or already used by another argument */


int traceprobe_conflict_field_name(const char *name,
			       struct probe_arg *args, int narg)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
		if (strcmp(reserved_field_names[i], name) == 0)
			return 1;

	for (i = 0; i < narg; i++)
		if (strcmp(args[i].name, name) == 0)
			return 1;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
89
100.00%
1
100.00%
Total
89
100.00%
1
100.00%



void traceprobe_update_arg(struct probe_arg *arg)
{
	if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
		update_bitfield_fetch_param(arg->fetch.data);
	else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
		update_deref_fetch_param(arg->fetch.data);
	else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
		update_symbol_cache(arg->fetch.data);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
78
100.00%
1
100.00%
Total
78
100.00%
1
100.00%



void traceprobe_free_probe_arg(struct probe_arg *arg)
{
	if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
		free_bitfield_fetch_param(arg->fetch.data);
	else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
		free_deref_fetch_param(arg->fetch.data);
	else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
		free_symbol_cache(arg->fetch.data);

	kfree(arg->name);
	kfree(arg->comm);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
92
100.00%
1
100.00%
Total
92
100.00%
1
100.00%



static int __set_print_fmt(struct trace_probe *tp, char *buf, int len,
			   bool is_return)
{
	int i;
	int pos = 0;

	const char *fmt, *arg;

	if (!is_return) {
		fmt = "(%lx)";
		arg = "REC->" FIELD_STRING_IP;
	} else {
		fmt = "(%lx <- %lx)";
		arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
	}

	/* When len=0, we just calculate the needed length */

#define LEN_OR_ZERO (len ? len - pos : 0)

	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);

	for (i = 0; i < tp->nr_args; i++) {
		pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
				tp->args[i].name, tp->args[i].type->fmt);
	}

	pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);

	for (i = 0; i < tp->nr_args; i++) {
		if (strcmp(tp->args[i].type->name, "string") == 0)
			pos += snprintf(buf + pos, LEN_OR_ZERO,
					", __get_str(%s)",
					tp->args[i].name);
		else
			pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
					tp->args[i].name);
	}


#undef LEN_OR_ZERO

	/* return the length of print_fmt */
	return pos;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Namhyung Kim
241
100.00%
1
100.00%
Total
241
100.00%
1
100.00%



int set_print_fmt(struct trace_probe *tp, bool is_return)
{
	int len;
	char *print_fmt;

	/* First: called with 0 length to calculate the needed length */
	len = __set_print_fmt(tp, NULL, 0, is_return);
	print_fmt = kmalloc(len + 1, GFP_KERNEL);
	if (!print_fmt)
		return -ENOMEM;

	/* Second: actually write the @print_fmt */
	__set_print_fmt(tp, print_fmt, len + 1, is_return);
	tp->call.print_fmt = print_fmt;

	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Namhyung Kim
79
100.00%
1
100.00%
Total
79
100.00%
1
100.00%

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Srikar Dronamraju
2203
69.54%
2
12.50%
Namhyung Kim
498
15.72%
5
31.25%
Omar Sandoval
220
6.94%
1
6.25%
Hyeoncheol Lee
118
3.72%
1
6.25%
Masami Hiramatsu
104
3.28%
4
25.00%
Stephen Rothwell
10
0.32%
1
6.25%
Steven Rostedt
8
0.25%
1
6.25%
Daniel Walter
7
0.22%
1
6.25%
Total
3168
100.00%
16
100.00%
Directory: kernel/trace

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.