Commit 1c20b1d1 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Arnaldo Carvalho de Melo
Browse files

perf probe: Show trace event definition 



Add --definition/-D option for showing the trace-event definition in
stdout. This can be useful in debugging or combined with a shell script.

e.g.
  ----
  # perf probe --definition 'do_sys_open $params'
  p:probe/do_sys_open _text+2261728 dfd=%di:s32 filename=%si:u64 flags=%dx:s32 mode=%cx:u16
  ----

Suggested-and-Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214226712.23638.2240534040014013658.stgit@devbox


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 893c5c79

tools/perf/Documentation/perf-probe.txt

+7 −0
Original line number Diff line number Diff line
@@ -21,6 +21,8 @@ or 
'perf probe' [options] --vars='PROBEPOINT'

or

'perf probe' [options] --funcs

or

'perf probe' [options] --definition='PROBE' [...]



DESCRIPTION

-----------
@@ -96,6 +98,11 @@ OPTIONS 
	can also list functions in a user space executable / shared library.

	This also can accept a FILTER rule argument.



-D::

--definition=::

	Show trace-event definition converted from given probe-event instead

	of write it into tracing/[k,u]probe_events.



--filter=FILTER::

	(Only for --vars and --funcs) Set filter. FILTER is a combination of glob

	pattern, see FILTER PATTERN for detail.

tools/perf/builtin-probe.c

+19 −7
Original line number Diff line number Diff line
@@ -326,6 +326,11 @@ static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs) 
	if (ret < 0)

		goto out_cleanup;



	if (params.command == 'D') {	/* it shows definition */

		ret = show_probe_trace_events(pevs, npevs);

		goto out_cleanup;

	}



	ret = apply_perf_probe_events(pevs, npevs);

	if (ret < 0)

		goto out_cleanup;
@@ -454,6 +459,14 @@ out: 
	return ret;

}



#ifdef HAVE_DWARF_SUPPORT

#define PROBEDEF_STR	\

	"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"

#else

#define PROBEDEF_STR	"[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"

#endif





static int

__cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)

{
@@ -479,13 +492,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) 
			     opt_set_filter_with_command, DEFAULT_LIST_FILTER),

	OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",

		     opt_set_filter_with_command),

	OPT_CALLBACK('a', "add", NULL,

#ifdef HAVE_DWARF_SUPPORT

		"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT"

		" [[NAME=]ARG ...]",

#else

		"[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]",

#endif

	OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,

		"probe point definition, where\n"

		"\t\tGROUP:\tGroup name (optional)\n"

		"\t\tEVENT:\tEvent name\n"
@@ -503,6 +510,9 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) 
		"\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",

#endif

		opt_add_probe_event),

	OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,

		"Show trace event definition of given traceevent for k/uprobe_events.",

		opt_add_probe_event),

	OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"

		    " with existing name"),

	OPT_CALLBACK('L', "line", NULL,
@@ -548,6 +558,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) 


	set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);

	set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);

	set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);

	set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);

#ifdef HAVE_DWARF_SUPPORT

	set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
@@ -644,6 +655,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) 
		}

		break;

	case 'a':

	case 'D':

		/* Ensure the last given target is used */

		if (params.target && !params.target_used) {

			pr_err("  Error: -x/-m must follow the probe definitions.\n");

tools/perf/util/probe-event.c

+46 −0
Original line number Diff line number Diff line
@@ -3207,6 +3207,52 @@ int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs) 
	return 0;

}



static int show_probe_trace_event(struct probe_trace_event *tev)

{

	char *buf = synthesize_probe_trace_command(tev);



	if (!buf) {

		pr_debug("Failed to synthesize probe trace event.\n");

		return -EINVAL;

	}



	/* Showing definition always go stdout */

	printf("%s\n", buf);

	free(buf);



	return 0;

}



int show_probe_trace_events(struct perf_probe_event *pevs, int npevs)

{

	struct strlist *namelist = strlist__new(NULL, NULL);

	struct probe_trace_event *tev;

	struct perf_probe_event *pev;

	int i, j, ret = 0;



	if (!namelist)

		return -ENOMEM;



	for (j = 0; j < npevs && !ret; j++) {

		pev = &pevs[j];

		for (i = 0; i < pev->ntevs && !ret; i++) {

			tev = &pev->tevs[i];

			/* Skip if the symbol is out of .text or blacklisted */

			if (!tev->point.symbol && !pev->uprobes)

				continue;



			/* Set new name for tev (and update namelist) */

			ret = probe_trace_event__set_name(tev, pev,

							  namelist, true);

			if (!ret)

				ret = show_probe_trace_event(tev);

		}

	}

	strlist__delete(namelist);



	return ret;

}



int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)

{

	int i, ret = 0;

tools/perf/util/probe-event.h

+1 −0
Original line number Diff line number Diff line
@@ -147,6 +147,7 @@ int line_range__init(struct line_range *lr); 
int add_perf_probe_events(struct perf_probe_event *pevs, int npevs);

int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs);

int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs);

int show_probe_trace_events(struct perf_probe_event *pevs, int npevs);

void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs);

int del_perf_probe_events(struct strfilter *filter);

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