Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'perf_urgent_for_v6.3_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Fix "same task" check when redirecting event output
- Do not wait unconditionally for RCU on the event migration path if
there are no events to migrate
* tag 'perf_urgent_for_v6.3_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix the same task check in perf_event_set_output
perf: Optimize perf_pmu_migrate_context()
+8
-6
+8
-6
kernel/events/core.c
+8
-6
kernel/events/core.c
···
12173
12173
/*
12174
12174
* If its not a per-cpu rb, it must be the same task.
12175
12175
*/
12176
-
if (output_event->cpu == -1 && output_event->ctx != event->ctx)
12176
+
if (output_event->cpu == -1 && output_event->hw.target != event->hw.target)
12177
12177
goto out;
12178
12178
12179
12179
/*
···
12893
12893
__perf_pmu_remove(src_ctx, src_cpu, pmu, &src_ctx->pinned_groups, &events);
12894
12894
__perf_pmu_remove(src_ctx, src_cpu, pmu, &src_ctx->flexible_groups, &events);
12895
12895
12896
-
/*
12897
-
* Wait for the events to quiesce before re-instating them.
12898
-
*/
12899
-
synchronize_rcu();
12896
+
if (!list_empty(&events)) {
12897
+
/*
12898
+
* Wait for the events to quiesce before re-instating them.
12899
+
*/
12900
+
synchronize_rcu();
12900
12901
12901
-
__perf_pmu_install(dst_ctx, dst_cpu, pmu, &events);
12902
+
__perf_pmu_install(dst_ctx, dst_cpu, pmu, &events);
12903
+
}
12902
12904
12903
12905
mutex_unlock(&dst_ctx->mutex);
12904
12906
mutex_unlock(&src_ctx->mutex);