Without this patch, the last output doesn't have timestamp appended if --timestamp-filename is not explicitly provided. For example:
# perf record -a --switch-output & [1] 11224 # kill -s SIGUSR2 11224 [ perf record: dump data: Woken up 1 times ] # [ perf record: Dump perf.data.2015122622372823 ] # fg perf record -a --switch-output ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.027 MB perf.data (540 samples) ] # ls -l total 836 -rw------- 1 root root 33256 Dec 26 22:37 perf.data <---- *Odd* -rw------- 1 root root 817156 Dec 26 22:37 perf.data.2015122622372823 Signed-off-by: Wang Nan <wangn...@huawei.com> Tested-by: Arnaldo Carvalho de Melo <a...@redhat.com> Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Masami Hiramatsu <mhira...@kernel.org> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Zefan Li <lize...@huawei.com> Cc: pi3or...@163.com Link: http://lkml.kernel.org/r/1460643725-167413-4-git-send-email-wangn...@huawei.com Signed-off-by: He Kuang <heku...@huawei.com> [ Updated man page, that also got an entry for --timestamp-filename ] Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/Documentation/perf-record.txt | 5 +++++ tools/perf/builtin-record.c | 3 +++ 2 files changed, 8 insertions(+) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index a77a431..79a8a14 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -347,6 +347,9 @@ Configure all used events to run in kernel space. --all-user:: Configure all used events to run in user space. +--timestamp-filename +Append timestamp to output file name. + --switch-output:: Generate multiple perf.data files, timestamp prefixed, switching to a new one when receiving a SIGUSR2. @@ -355,6 +358,8 @@ A possible use case is to, given an external event, slice the perf.data file that gets then processed, possibly via a perf script, to decide if that particular perf.data snapshot should be kept or not. +Implies --timestamp-filename. + SEE ALSO -------- linkperf:perf-stat[1], linkperf:perf-list[1] diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 72246e2..3676af4 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1344,6 +1344,9 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused) return -EINVAL; } + if (rec->switch_output) + rec->timestamp_filename = true; + if (!rec->itr) { rec->itr = auxtrace_record__init(rec->evlist, &err); if (err) -- 1.8.3.4
