perf record: Add switch-output time option argument

It's now possible to specify the threshold time for perf.data like:

  $ perf record --switch-output=30s ...

Once it's reached, the current data are dumped in to the
perf.data.<timestamp> file and session does on.

  $ perf record --switch-output=30s ...
  [ perf record: dump data: Woken up 44 times ]
  [ perf record: Dump perf.data.2017010213043746 ]
  ...

The time is expected to be a number with appended unit
character - s/m/h/d.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Wang Nan <wangnan0@huawei.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/1483955520-29063-7-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 3d55d2fd48b3..27256bc68eda 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -427,6 +427,8 @@ based on 'mode' value:
   "signal" - when receiving a SIGUSR2 (default value) or
   <size>   - when reaching the size threshold, size is expected to
              be a number with appended unit character - B/K/M/G
+  <time>   - when reaching the time threshold, size is expected to
+             be a number with appended unit character - s/m/h/d
 
              Note: the precision of  the size  threshold  hugely depends
              on your configuration  - the number and size of  your  ring