On Wed, Jul 31, 2019 at 05:30:35PM +0300, Alexander Shishkin wrote:
> +static void perf_put_aux_event(struct perf_event *event)
> +{
> + struct perf_event_context *ctx = event->ctx;
> + struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
> + struct perf_event *iter = NULL;
> +
> + /*
> + * If event uses aux_event tear down the link
> + */
> + if (event->aux_event) {
> + put_event(event->aux_event);
> + event->aux_event = NULL;
Those lines should probably be reversed; put_event() should be done
after clearing the link.
It probably doesn't matter, but it is confusing.
> + return;
> + }
> +
> + /*
> + * If the event is an aux_event, tear down all links to
> + * it from other events.
> + */
> + for_each_sibling_event(iter, event->group_leader) {
> + if (iter->aux_event != event)
> + continue;
> +
> + iter->aux_event = NULL;
> + put_event(event);
> +
> + /*
> + * If it's ACTIVE, schedule it out. It won't schedule
> + * again because !aux_event.
> + */
> + event_sched_out(iter, cpuctx, ctx);
> + }
> +}
