Re: [PATCH] backing_dev: Fix hung task on sync

[Tejun Heo]

Hello, Jan.

On Wed, Feb 19, 2014 at 10:27:31AM +0100, Jan Kara wrote:
>   You are the workqueue expert so you may know better ;) But the way I
> understand it is that queue_delayed_work() does nothing if the timer is
> already running. Since we queue flusher work to run either immediately or
> after dirty_writeback_interval we are safe to run queue_delayed_work()
> whenever we want it to run after dirty_writeback_interval and
> mod_delayed_work() whenever we want to run it immediately.

Ah, okay, so it's always mod on immediate and queue on delayed.  Yeah,
that should work.

> But it's subtle and some interface where we could say queue delayed work
> after no later than X would be easier to grasp.

Yeah, I think it'd be better if we had something like
mod_delayed_work_if_later().  Hmm...

Thanks.

-- 
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/