From 02f9b50e04812782fd006ed21c6da1c5e3e373da Mon Sep 17 00:00:00 2001 From: Yang Jihong Date: Fri, 19 Jan 2024 04:03:03 +0000 Subject: perf record: Check conflict between '--timestamp-filename' option and pipe mode before recording 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 Acked-by: Namhyung Kim Link: https://lore.kernel.org/r/20240119040304.3708522-3-yangjihong1@huawei.com Signed-off-by: Namhyung Kim --- tools/perf/util/data.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'tools/perf/util/data.c') diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c index c29d8a382b19..550675ce0b78 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; -- cgit v1.2.3