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: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami 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: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Masami Hiramatsu 2016-08-26 01:24:27 +09:00 committed by Arnaldo Carvalho de Melo
parent 893c5c798b
commit 1c20b1d154
4 changed files with 73 additions and 7 deletions

View File

@ -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.

View File

@ -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");

View File

@ -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;

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@ -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);