The call to smp_call_function_single in perf_event_read() may fail and, when it does, its error value is the one to return.
Signed-off-by: David Carrillo-Cisneros <[email protected]> Reviewed-by: Stephane Eranian <[email protected]> --- kernel/events/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 9345028..ebc187f 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3469,9 +3469,9 @@ static int perf_event_read(struct perf_event *event, bool group) .group = group, .ret = 0, }; - smp_call_function_single(event->oncpu, - __perf_event_read, &data, 1); + ret = smp_call_function_single(event->oncpu, + __perf_event_read, &data, 1); - ret = data.ret; + ret = ret ? : data.ret; } else if (event->state == PERF_EVENT_STATE_INACTIVE) { struct perf_event_context *ctx = event->ctx; unsigned long flags; -- 2.8.0.rc3.226.g39d4020
