diff options
| author | Nelson Elhage <nelhage@nelhage.com> | 2011-12-19 08:39:32 -0500 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2011-12-23 16:53:58 -0200 |
| commit | 41d0d933494ce10eb77758a1168b08e317c42e8e (patch) | |
| tree | f907773714846b5b5cf85b4f450bb6fe07b168d4 /tools/perf/builtin-record.c | |
| parent | 18e6093904abfd51671ff5846c2fdaba9ebbf21b (diff) | |
perf: builtin-record: Document and check that mmap_pages must be a power of two.
Now that we automatically point users at it, let's provide them some
guidance so that they hopefully don't just get mysterious EINVAL's
from the kernel.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1324301972-22740-4-git-send-email-nelhage@nelhage.com
Signed-off-by: Nelson Elhage <nelhage@nelhage.com>
[ committer note: Made it work after 50a682c ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-record.c')
| -rw-r--r-- | tools/perf/builtin-record.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 56bb4476e3b..e873ae2dd54 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -279,6 +279,9 @@ try_again: "/proc/sys/kernel/perf_event_mlock_kb,\n" "or try again with a smaller value of -m/--mmap_pages.\n" "(current value: %d)\n", opts->mmap_pages); + else if (!is_power_of_2(opts->mmap_pages)) + die("--mmap_pages/-m value must be a power of two."); + die("failed to mmap with %d (%s)\n", errno, strerror(errno)); } |