diff options
| author | James Hogan <james.hogan@imgtec.com> | 2013-02-27 16:16:38 +0000 |
|---|---|---|
| committer | James Hogan <james.hogan@imgtec.com> | 2013-03-15 13:19:54 +0000 |
| commit | c43ca04b5e7854b3996f84a495e4553941e76266 (patch) | |
| tree | 73cd4ed7b8ef214b8d9cd366611b566303628a2e /arch/metag/kernel/perf/perf_event.c | |
| parent | 3424dabb6508d538e9ec1a2aa889fefbd83df2d0 (diff) | |
metag: perf: fix wrap handling in delta calculation
When calculating the delta, mask with MAX_PERIOD (24 bits) to handle
wrapping, which particularly happens with periodic sampling since the
value is intentionally set so that it will overflow soon.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Diffstat (limited to 'arch/metag/kernel/perf/perf_event.c')
| -rw-r--r-- | arch/metag/kernel/perf/perf_event.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/metag/kernel/perf/perf_event.c b/arch/metag/kernel/perf/perf_event.c index f38bf6d4dc5..8096db2a550 100644 --- a/arch/metag/kernel/perf/perf_event.c +++ b/arch/metag/kernel/perf/perf_event.c @@ -211,7 +211,7 @@ again: /* * Calculate the delta and add it to the counter. */ - delta = new_raw_count - prev_raw_count; + delta = (new_raw_count - prev_raw_count) & MAX_PERIOD; local64_add(delta, &event->count); } |