On 10/22/15 6:57 AM, Peter Zijlstra wrote:
On Wed, Oct 21, 2015 at 03:58:03PM -0700, Alexei Starovoitov wrote:diff --git a/kernel/events/core.c b/kernel/events/core.c index 64754bfecd70..0b6333265872 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3258,7 +3258,7 @@ static inline u64 perf_event_count(struct perf_event *event) u64 perf_event_read_local(struct perf_event *event) { unsigned long flags; - u64 val; + u64 val = -EINVAL;No, you cannot do this, -EINVAL is a valid count value. You simply must not call this function on !local events, ever.
agree. Will keep perf_event_read_local() as-is and do all safety checks on bpf side. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
