On Thu, Jun 04, 2015 at 12:49:02PM +0200, Peter Zijlstra wrote: > Needs more comments at the very least, its fully of trickery. > > @@ -1118,10 +1125,16 @@ static void __run_hrtimer(struct hrtimer > enum hrtimer_restart (*fn)(struct hrtimer *); > int restart; > > - WARN_ON(!irqs_disabled()); > + lockdep_assert_held(&cpu_base->lock); > > debug_deactivate(timer); > - base->running = timer; > + cpu_base->running = timer; > + > + /* > + * separate the ->running assignment from the ->state assignment > + */ > + write_seqcount_begin(&cpu_base->seq);
Maybe these need to be raw_write_seqcount_latch().. > + > __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0); > timer_stats_account_hrtimer(timer); > fn = timer->function; > @@ -1150,8 +1163,13 @@ static void __run_hrtimer(struct hrtimer > !(timer->state & HRTIMER_STATE_ENQUEUED)) > enqueue_hrtimer(timer, base); > > - WARN_ON_ONCE(base->running != timer); > - base->running = NULL; > + /* > + * separate the ->running assignment from the ->state assignment > + */ > + write_seqcount_end(&cpu_base->seq); > + > + WARN_ON_ONCE(cpu_base->running != timer); > + cpu_base->running = NULL; > } > > static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t > now) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
