diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/perf_event.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 3472bb1a070c..0c714226ae0c 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -941,6 +941,7 @@ static void perf_group_attach(struct perf_event *event) static void list_del_event(struct perf_event *event, struct perf_event_context *ctx) { + struct perf_cpu_context *cpuctx; /* * We can have double detach due to exit/hot-unplug + close. */ @@ -949,8 +950,17 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx) event->attach_state &= ~PERF_ATTACH_CONTEXT; - if (is_cgroup_event(event)) + if (is_cgroup_event(event)) { ctx->nr_cgroups--; + cpuctx = __get_cpu_context(ctx); + /* + * if there are no more cgroup events + * then cler cgrp to avoid stale pointer + * in update_cgrp_time_from_cpuctx() + */ + if (!ctx->nr_cgroups) + cpuctx->cgrp = NULL; + } ctx->nr_events--; if (event->attr.inherit_stat) |