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| author | Jiri Olsa <jolsa@kernel.org> | 2014-06-02 13:44:23 -0400 |
|---|---|---|
| committer | Jiri Olsa <jolsa@kernel.org> | 2014-06-03 21:35:05 +0200 |
| commit | a515114fa3cff8f1da10cd68914d55c10879c3e0 (patch) | |
| tree | aeb310420822d6a7ca0ec2bf7d8d5dae80588f54 /tools | |
| parent | f29984226978313039d7dfe9b45eaa55a3aad03d (diff) | |
| download | linux-a515114fa3cff8f1da10cd68914d55c10879c3e0.tar.bz2 | |
perf record: Fix poll return value propagation
If the perf record command is interrupted in record__mmap_read_all
function, the 'done' is set and err has the latest poll return
value, which is most likely positive number (= number of pollfds
ready to read).
This 'positive err' is then propagated to the exit code, resulting
in not finishing the perf.data header properly, causing following
error in report:
# perf record -F 50000 -a
---
make the system real busy, so there's more chance
to interrupt perf in event writing code
---
^C[ perf record: Woken up 16 times to write data ]
[ perf record: Captured and wrote 30.292 MB perf.data (~1323468 samples) ]
# perf report --stdio > /dev/null
WARNING: The perf.data file's data size field is 0 which is unexpected.
Was the 'perf record' command properly terminated?
Fixing this by checking for positive poll return value
and setting err to 0.
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1401732126-19465-1-git-send-email-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/builtin-record.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index e4c85b8f46c2..ce2cfec5c764 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -454,7 +454,11 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) if (done) break; err = poll(rec->evlist->pollfd, rec->evlist->nr_fds, -1); - if (err < 0 && errno == EINTR) + /* + * Propagate error, only if there's any. Ignore positive + * number of returned events and interrupt error. + */ + if (err > 0 || (err < 0 && errno == EINTR)) err = 0; waking++; } |