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We can just traverse >> through all pmu events of both cpu subtrees. > > But imagine the case where we have 50 event for a PMU that can only > schedule 8. Then we have to iterate 42 events for naught instead of > directly jumping to the next PMU. Yes, that needs to be handled. And, IIRC, you proposed maintaining a list of leftmost event from each pmu subtree. Thanks, Ravi