Re: [PATCH 4/4] sched: add hooks for workqueue

From: Peter Zijlstra
Date: Mon May 31 2010 - 04:01:11 EST


On Thu, 2010-05-13 at 12:48 +0200, Tejun Heo wrote:
> Concurrency managed workqueue needs to know when workers are going to
> sleep and waking up, and, when a worker goes to sleep, be able to wake
> up another worker to maintain adequate concurrency. This patch
> introduces PF_WQ_WORKER to identify workqueue workers and adds the
> following two hooks.
>
> * wq_worker_waking_up(): called when a worker is woken up.
>
> * wq_worker_sleeping(): called when a worker is going to sleep and may
> return a pointer to a local task which should be woken up. The
> returned task is woken up using try_to_wake_up_local() which is
> simplified ttwu which is called under rq lock and can only wake up
> local tasks.

This changelog seems to lack explanation for why you need the wakeup
callback.
--
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/