[tip:perf/core] perf stat record: Add pipe support for record command

tip-bot for Jiri Olsa
2015-12-18T09:12:54Z

Commit-ID: 664c98d4e1c2ff60627d78d4c8ae81cd2df13783
Gitweb: http://git.kernel.org/tip/664c98d4e1c2ff60627d78d4c8ae81cd2df13783
Author: Jiri Olsa <jolsa@kernel.org>
AuthorDate: Thu, 5 Nov 2015 15:40:50 +0100
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 17 Dec 2015 15:15:22 -0300

perf stat record: Add pipe support for record command

Allowing storing stat record data into pipe, so report tools
(report/script) could read data directly from record.

Committer note:

Before this patch:

$ perf stat record -o - usleep 1 | perf report -i -
incompatible file format (rerun with -v to learn more)
$ perf stat record -o - usleep 1 | perf script -i -
incompatible file format (rerun with -v to learn more)
$ ls -la perf.data
ls: cannot access perf.data: No such file or directory
$

After:

$ perf stat record -o - usleep 1 | perf report -i -
# To display the perf.data header info, please use
# --header/--header-only options.
#
Error:
The - file has no samples!
$ perf stat record -o - usleep 1 | perf script -i -
Display of symbols requested but neither sample IP nor sample address
is selected. Hence, no addresses to convert to symbols.
0 [0x80]: failed to process type: 64
$ ls -la perf.data
ls: cannot access perf.data: No such file or directory
$

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Kan Liang <kan.liang@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446734469-11352-7-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-stat.c | 39 ++++++++++++++++++++++++++++-----------
1 file changed, 28 insertions(+), 11 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 39d0c30f..8a2f9ce 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -317,10 +317,19 @@ static void workload_exec_failed_signal(int signo __maybe_unused, siginfo_t *inf
workload_exec_errno = info->si_value.sival_int;
}

-static int perf_stat_synthesize_config(void)
+static int perf_stat_synthesize_config(bool is_pipe)
{
int err;

+ if (is_pipe) {
+ err = perf_event__synthesize_attrs(NULL, perf_stat.session,
+ process_synthesized_event);
+ if (err < 0) {
+ pr_err("Couldn't synthesize attrs.\n");
+ return err;
+ }
+ }
+
err = perf_event__synthesize_thread_map2(NULL, evsel_list->threads,
process_synthesized_event,
NULL);
@@ -388,6 +397,7 @@ static int __run_perf_stat(int argc, const char **argv)
size_t l;
int status = 0;
const bool forks = (argc > 0);
+ bool is_pipe = STAT_RECORD ? perf_stat.file.is_pipe : false;

if (interval) {
ts.tv_sec = interval / 1000;
@@ -398,7 +408,7 @@ static int __run_perf_stat(int argc, const char **argv)
}

if (forks) {
- if (perf_evlist__prepare_workload(evsel_list, &target, argv, false,
+ if (perf_evlist__prepare_workload(evsel_list, &target, argv, is_pipe,
workload_exec_failed_signal) < 0) {
perror("failed to prepare workload");
return -1;
@@ -457,12 +467,17 @@ static int __run_perf_stat(int argc, const char **argv)
if (STAT_RECORD) {
int err, fd = perf_data_file__fd(&perf_stat.file);

- err = perf_session__write_header(perf_stat.session, evsel_list,
- fd, false);
+ if (is_pipe) {
+ err = perf_header__write_pipe(perf_data_file__fd(&perf_stat.file));
+ } else {
+ err = perf_session__write_header(perf_stat.session, evsel_list,
+ fd, false);
+ }
+
if (err < 0)
return err;

- err = perf_stat_synthesize_config();
+ err = perf_stat_synthesize_config(is_pipe);
if (err < 0)
return err;
}
@@ -970,6 +985,10 @@ static void print_counters(struct timespec *ts, int argc, const char **argv)
struct perf_evsel *counter;
char buf[64], *prefix = NULL;

+ /* Do not print anything if we record to the pipe. */
+ if (STAT_RECORD && perf_stat.file.is_pipe)
+ return;
+
if (interval)
print_interval(prefix = buf, ts);
else
@@ -1402,10 +1421,6 @@ static int __cmd_record(int argc, const char **argv)
return -1;
}

- /* No pipe support ATM */
- if (perf_stat.file.is_pipe)
- return -EINVAL;
-
init_features(session);

session->evlist = evsel_list;
@@ -1636,8 +1651,10 @@ int cmd_stat(int argc, const char **argv, const char *prefix __maybe_unused)
"older tools may produce warnings about this file\n.");
}

- perf_stat.session->header.data_size += perf_stat.bytes_written;
- perf_session__write_header(perf_stat.session, evsel_list, fd, true);
+ if (!perf_stat.file.is_pipe) {
+ perf_stat.session->header.data_size += perf_stat.bytes_written;
+ perf_session__write_header(perf_stat.session, evsel_list, fd, true);
+ }

perf_session__delete(perf_stat.session);
}