Messages in this thread Patch in this message | | | From | Yanfei Xu <> | Subject | [PATCH] perf/core: remove a meaningless pair of rcu_read_{,un}lock() | Date | Wed, 8 Jun 2022 17:09:38 +0800 |
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Per the codes, this pair of rcu_read_{,un}lock() protects nothing. Let's remove it.
Further, the variable "pmu" is safe as it is in the SRCU read-side critical scope of "pmus_srcu" and perf_pmu_unregister() delete it after calling synchronize_srcu.
Signed-off-by: Yanfei Xu <yanfei.xu@intel.com> --- kernel/events/core.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index 950b25c3f210..36b0df6feab4 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -11296,9 +11296,7 @@ static struct pmu *perf_init_event(struct perf_event *event) } again: - rcu_read_lock(); pmu = idr_find(&pmu_idr, type); - rcu_read_unlock(); if (pmu) { if (event->attr.type != type && type != PERF_TYPE_RAW && !(pmu->capabilities & PERF_PMU_CAP_EXTENDED_HW_TYPE)) -- 2.32.0
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