Commit 9551fbb6 authored by Ravi Bangoria's avatar Ravi Bangoria Committed by Peter Zijlstra
Browse files

perf/core: Remove pmu linear searching code 



Searching for the right pmu by iterating over all pmus is no longer
required since all pmus now *must* be present in the 'pmu_idr' list.
So, remove linear searching code.

Signed-off-by: default avatarRavi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230504110003.2548-4-ravi.bangoria@amd.com
parent 2fad201f

kernel/events/core.c

+13 −24
Original line number Diff line number Diff line
@@ -11630,10 +11630,13 @@ static struct pmu *perf_init_event(struct perf_event *event) 
	}



again:

	ret = -ENOENT;

	rcu_read_lock();

	pmu = idr_find(&pmu_idr, type);

	rcu_read_unlock();

	if (pmu) {

	if (!pmu)

		goto fail;



	if (event->attr.type != type && type != PERF_TYPE_RAW &&

	    !(pmu->capabilities & PERF_PMU_CAP_EXTENDED_HW_TYPE))

		goto fail;
@@ -11644,24 +11647,10 @@ static struct pmu *perf_init_event(struct perf_event *event) 
		goto again;

	}



fail:

	if (ret)

		pmu = ERR_PTR(ret);



		goto unlock;

	}



	list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) {

		ret = perf_try_init_event(pmu, event);

		if (!ret)

			goto unlock;



		if (ret != -ENOENT) {

			pmu = ERR_PTR(ret);

			goto unlock;

		}

	}

fail:

	pmu = ERR_PTR(-ENOENT);

unlock:

	srcu_read_unlock(&pmus_srcu, idx);