• Jiri Olsa's avatar
    perf record: Fix poll return value propagation · a515114f
    Jiri Olsa authored
    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: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    Acked-by: default avatarNamhyung 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.orgSigned-off-by: default avatarJiri Olsa <jolsa@kernel.org>
    a515114f
builtin-record.c 24.2 KB