Commit fb1587d8 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Ingo Molnar
Browse files

perf probe: List probes with line number and file name 



Improve --list to show current exist probes with line number and
file name. This enables user easily to check which line is
already probed.

for example:

 ./perf probe --list
 probe:vfs_read       (on vfs_read:8@linux-2.6-tip/fs/read_write.c)

Signed-off-by: default avatarMasami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220619.32050.48702.stgit@localhost6.localdomain6>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 4235b045

tools/perf/util/probe-event.c

+42 −13
Original line number Diff line number Diff line
@@ -70,7 +70,6 @@ static int e_snprintf(char *str, size_t size, const char *format, ...) 
	return ret;

}





static struct map_groups kmap_groups;

static struct map *kmaps[MAP__NR_TYPES];
@@ -357,27 +356,39 @@ void parse_kprobe_trace_command(const char *cmd, struct kprobe_trace_event *tev) 
/* Compose only probe point (not argument) */

static char *synthesize_perf_probe_point(struct perf_probe_point *pp)

{

	char *buf;

	char offs[64] = "", line[64] = "";

	int ret;

	char *buf, *tmp;

	char offs[32] = "", line[32] = "", file[32] = "";

	int ret, len;



	buf = xzalloc(MAX_CMDLEN);

	if (pp->offset) {

		ret = e_snprintf(offs, 64, "+%lu", pp->offset);

		ret = e_snprintf(offs, 32, "+%lu", pp->offset);

		if (ret <= 0)

			goto error;

	}

	if (pp->line) {

		ret = e_snprintf(line, 64, ":%d", pp->line);

		ret = e_snprintf(line, 32, ":%d", pp->line);

		if (ret <= 0)

			goto error;

	}

	if (pp->file) {

		len = strlen(pp->file) - 32;

		if (len < 0)

			len = 0;

		tmp = strchr(pp->file + len, '/');

		if (!tmp)

			tmp = pp->file + len - 1;

		ret = e_snprintf(file, 32, "@%s", tmp + 1);

		if (ret <= 0)

			goto error;

	}



	if (pp->function)

		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->function,

				 offs, pp->retprobe ? "%return" : "", line);

		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,

				 offs, pp->retprobe ? "%return" : "", line,

				 file);

	else

		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", pp->file, line);

		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);

	if (ret <= 0)

		goto error;
@@ -511,15 +522,32 @@ void convert_to_perf_probe_event(struct kprobe_trace_event *tev, 
{

	char buf[64];

	int i;

#ifndef NO_DWARF_SUPPORT

	struct symbol *sym;

	int fd, ret = 0;



	pev->event = xstrdup(tev->event);

	pev->group = xstrdup(tev->group);



	sym = map__find_symbol_by_name(kmaps[MAP__FUNCTION],

				       tev->point.symbol, NULL);

	if (sym) {

		fd = open_vmlinux();

		ret = find_perf_probe_point(fd, sym->start + tev->point.offset,

					    &pev->point);

		close(fd);

	}

	if (ret <= 0) {

		pev->point.function = xstrdup(tev->point.symbol);

		pev->point.offset = tev->point.offset;

	}

#else

	/* Convert trace_point to probe_point */

	pev->point.function = xstrdup(tev->point.symbol);

	pev->point.offset = tev->point.offset;

#endif

	pev->point.retprobe = tev->point.retprobe;



	pev->event = xstrdup(tev->event);

	pev->group = xstrdup(tev->group);



	/* Convert trace_arg to probe_arg */

	pev->nargs = tev->nargs;

	pev->args = xzalloc(sizeof(struct perf_probe_arg) * pev->nargs);
@@ -650,7 +678,7 @@ static void show_perf_probe_event(struct perf_probe_event *pev) 
	ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);

	if (ret < 0)

		die("Failed to copy event: %s", strerror(-ret));

	printf("  %-40s (on %s", buf, place);

	printf("  %-20s (on %s", buf, place);



	if (pev->nargs > 0) {

		printf(" with");
@@ -671,6 +699,7 @@ void show_perf_probe_events(void) 
	struct str_node *ent;



	setup_pager();

	init_vmlinux();



	memset(&tev, 0, sizeof(tev));

	memset(&pev, 0, sizeof(pev));

tools/perf/util/probe-finder.c

+70 −0
Original line number Diff line number Diff line
@@ -693,6 +693,76 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev, 
	return pf.ntevs;

}



/* Reverse search */

int find_perf_probe_point(int fd, unsigned long addr,

			  struct perf_probe_point *ppt)

{

	Dwarf_Die cudie, spdie, indie;

	Dwarf *dbg;

	Dwarf_Line *line;

	Dwarf_Addr laddr, eaddr;

	const char *tmp;

	int lineno, ret = 0;



	dbg = dwarf_begin(fd, DWARF_C_READ);

	if (!dbg)

		return -ENOENT;



	/* Find cu die */

	if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie))

		return -EINVAL;



	/* Find a corresponding line */

	line = dwarf_getsrc_die(&cudie, (Dwarf_Addr)addr);

	if (line) {

		dwarf_lineaddr(line, &laddr);

		if ((Dwarf_Addr)addr == laddr) {

			dwarf_lineno(line, &lineno);

			ppt->line = lineno;



			tmp = dwarf_linesrc(line, NULL, NULL);

			DIE_IF(!tmp);

			ppt->file = xstrdup(tmp);

			ret = 1;

		}

	}



	/* Find a corresponding function */

	if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) {

		tmp = dwarf_diename(&spdie);

		if (!tmp)

			goto end;



		dwarf_entrypc(&spdie, &eaddr);

		if (!lineno) {

			/* We don't have a line number, let's use offset */

			ppt->function = xstrdup(tmp);

			ppt->offset = addr - (unsigned long)eaddr;

			ret = 1;

			goto end;

		}

		if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr, &indie)) {

			/* addr in an inline function */

			tmp = dwarf_diename(&indie);

			if (!tmp)

				goto end;

			dwarf_decl_line(&indie, &lineno);

		} else {

			if (eaddr == addr)	/* No offset: function entry */

				lineno = ppt->line;

			else

				dwarf_decl_line(&spdie, &lineno);

		}

		ppt->function = xstrdup(tmp);

		ppt->line -= lineno;	/* Make a relative line number */

	}



end:

	dwarf_end(dbg);

	return ret;

}





/* Find line range from its line number */

static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)

{

tools/perf/util/probe-finder.h

+4 −0
Original line number Diff line number Diff line
@@ -20,6 +20,10 @@ static inline int is_c_varname(const char *name) 
extern int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,

				    struct kprobe_trace_event **tevs);



/* Find a perf_probe_point from debuginfo */

extern int find_perf_probe_point(int fd, unsigned long addr,

				 struct perf_probe_point *ppt);



extern int find_line_range(int fd, struct line_range *lr);



#include <dwarf.h>

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