perf: Annotate cpuctx->ctx.mutex to avoid a lockdep splat

[mirror_ubuntu-bionic-kernel.git] / kernel / perf_event.c

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 244ca3acb0ee2117db88c96d57182a22e750ba1b..c5fa717cf0991ecba0ca9d6244d386f1e8fda4a6 100644 (file)
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -5380,6 +5380,8 @@ free_dev:
        goto out;
 }
 
+static struct lock_class_key cpuctx_mutex;
+
 int perf_pmu_register(struct pmu *pmu, char *name, int type)
 {
        int cpu, ret;
@@ -5428,6 +5430,7 @@ skip_type:
 
                cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu);
                __perf_event_init_context(&cpuctx->ctx);
+               lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex);
                cpuctx->ctx.type = cpu_context;
                cpuctx->ctx.pmu = pmu;
                cpuctx->jiffies_interval = 1;