[PATCH 2/5] perf: Move free outside of the mutex

From: Lucas De Marchi
Date: Tue Oct 08 2024 - 14:36:34 EST


It's not needed to hold the mutex to free the percpu variables stored in
pmu. Move them outside of the mutex protection in preparation for
possibly allowing them to live longer, according to the lifecycle of the
object owning/containing the pmu.

Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
---
kernel/events/core.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 3b8b85adb10a..6395dbf67671 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11845,7 +11845,6 @@ void perf_pmu_unregister(struct pmu *pmu)
synchronize_srcu(&pmus_srcu);
synchronize_rcu();

- free_percpu(pmu->pmu_disable_count);
idr_remove(&pmu_idr, pmu->type);
if (pmu_bus_running && pmu->dev && pmu->dev != PMU_NULL_DEV) {
if (pmu->nr_addr_filters)
@@ -11853,8 +11852,11 @@ void perf_pmu_unregister(struct pmu *pmu)
device_del(pmu->dev);
put_device(pmu->dev);
}
- free_pmu_context(pmu);
+
mutex_unlock(&pmus_lock);
+
+ free_percpu(pmu->pmu_disable_count);
+ free_pmu_context(pmu);
}
EXPORT_SYMBOL_GPL(perf_pmu_unregister);

--
2.46.2