On 7/21/2020 10:31 AM, pet...@infradead.org wrote:
On Tue, Jul 21, 2020 at 10:23:36AM -0400, Liang, Kan wrote:
Patch 13 forces the slots event to be part of a metric group. In patch 7,
for a metric group, we only update the values once with slots event.
I think the normal case mentioned above should not happen.
+ /* Only need to call update_topdown_event() once for group read. */
+ if ((cpuc->txn_flags & PERF_PMU_TXN_READ) &&
+ !is_slots_event(event))
+ return;
+
+ perf_pmu_disable(event->pmu);
+ x86_pmu.update_topdown_event(event);
+ perf_pmu_enable(event->pmu);
Ah, I missed that.
That also requires SLOTS to be the leader so that it will be the first
read. Did we enforce that somewhere?
I think it's missed in the current patch set. The suggested code in
patch 11 forces SLOTS to be the leader. I will apply it in V7.
Thanks,
Kan
