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perf: Fix event multiplexing for exclusive groups

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Commit 9e6302056f ("perf: Use hrtimers for event multiplexing")
placed the hrtimer (re)start call in the wrong place.  Instead of
capturing all scheduling failures, it only considered the PMU failure.

The result is that groups using perf_event_attr::exclusive are no
longer rotated.

Fixes: 9e6302056f ("perf: Use hrtimers for event multiplexing")
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201029162902.038667689@infradead.org
This commit is contained in:
Peter Zijlstra 2020-10-29 16:29:53 +01:00
parent 251ff2d493
commit 2714c3962f
1 changed files with 1 additions and 1 deletions
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2
kernel/events/core.c
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@ -2612,7 +2612,6 @@ group_sched_in(struct perf_event *group_event,
error:
pmu->cancel_txn(pmu);
perf_mux_hrtimer_restart(cpuctx);
return -EAGAIN;
}
@ -3672,6 +3671,7 @@ static int merge_sched_in(struct perf_event *event, void *data)
*can_add_hw = 0;
ctx->rotate_necessary = 1;
perf_mux_hrtimer_restart(cpuctx);
}
return 0;