[PATCH 6.7 413/713] perf record: Check conflict between '--timestamp-filename' option and pipe mode before recording

Sasha Levin
2024-03-24T22:54:08Z

From: Yang Jihong <yangjihong1@huawei.com>

[ Upstream commit 02f9b50e04812782fd006ed21c6da1c5e3e373da ]

In pipe mode, no need to switch perf data output, therefore,
'--timestamp-filename' option should not take effect.
Check the conflict before recording and output WARNING.
In this case, the check pipe mode in perf_data__switch() can be removed.

Before:

# perf record --timestamp-filename -o- perf test -w noploop | perf report -i- --percent-limit=1
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Dump -.2024011812110182 ]
#
# Total Lost Samples: 0
#
# Samples: 4K of event 'cycles:P'
# Event count (approx.): 2176784359
#
# Overhead Command Shared Object Symbol
# ........ ....... .................... ......................................
#
97.83% perf perf [.] noploop

#
# (Tip: Print event counts in CSV format with: perf stat -x,)
#

After:

# perf record --timestamp-filename -o- perf test -w noploop | perf report -i- --percent-limit=1
WARNING: --timestamp-filename option is not available in pipe mode.
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
#
# Total Lost Samples: 0
#
# Samples: 4K of event 'cycles:P'
# Event count (approx.): 2185575421
#
# Overhead Command Shared Object Symbol
# ........ ....... ..................... .............................................
#
97.75% perf perf [.] noploop

#
# (Tip: Profiling branch (mis)predictions with: perf record -b / perf report)
#

Fixes: ecfd7a9c044e ("perf record: Add '--timestamp-filename' option to append timestamp to output file name")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240119040304.3708522-3-yangjihong1@huawei.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/perf/builtin-record.c | 5 +++++
tools/perf/util/data.c | 2 --
2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index b7f8c94d052d0..5d86aa5ff5367 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -2449,6 +2449,11 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
if (data->is_pipe && rec->evlist->core.nr_entries == 1)
rec->opts.sample_id = true;

+ if (rec->timestamp_filename && perf_data__is_pipe(data)) {
+ rec->timestamp_filename = false;
+ pr_warning("WARNING: --timestamp-filename option is not available in pipe mode.\n");
+ }
+
evlist__uniquify_name(rec->evlist);

/* Debug message used by test scripts */
diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c
index c29d8a382b196..550675ce0b787 100644
--- a/tools/perf/util/data.c
+++ b/tools/perf/util/data.c
@@ -430,8 +430,6 @@ int perf_data__switch(struct perf_data *data,
{
int ret;

- if (check_pipe(data))
- return -EINVAL;
if (perf_data__is_read(data))
return -EINVAL;

--
2.43.0