On 05/05, Tom Zanussi wrote: > > This patch makes relay use timers instead of workqueues for reader > waking.
A couple of very minor nits, > @@ -337,11 +334,11 @@ static void __relay_reset(struct rchan_buf *buf, > unsigned int init) > if (init) { > init_waitqueue_head(&buf->read_wait); > kref_init(&buf->kref); > - INIT_DELAYED_WORK(&buf->wake_readers, NULL); > - } else { > - cancel_delayed_work(&buf->wake_readers); > - flush_scheduled_work(); > - } > + init_timer(&buf->timer); > + buf->timer.data = (unsigned long)buf; > + buf->timer.function = wakeup_readers; I'd suggest to use setup_timer(&buf->timer, wakeup_readers, buf); > @@ -609,9 +605,16 @@ size_t relay_switch_subbuf(struct rchan_buf *buf, size_t > length) > buf->padding[old_subbuf]; > smp_mb(); > if (waitqueue_active(&buf->read_wait)) { > - PREPARE_DELAYED_WORK(&buf->wake_readers, > - wakeup_readers); > - schedule_delayed_work(&buf->wake_readers, 1); > + /* > + * Calling wake_up_interruptible() from here > + * will deadlock if we happen to be logging > + * from the scheduler (trying to re-grab > + * rq->lock), so defer it. > + */ > + if (!timer_pending(&buf->timer)) { > + buf->timer.expires = jiffies + 1; > + add_timer(&buf->timer); > + } I think it is better to use __mod_timer(&buf->timer, jiffies + 1). In that case this "if (!timer_pending(&buf->timer))" is not strictly needed, yes? Imho, add_timer() is almost never should be used. The only valid usage is when timer->expires was already set by somebody else. Btw, thanks for your explanation about deferred wakeup. Oleg. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/