Re: [PATCH 1/2] kthread_worker: reorganize to prepare forflush_kthread_work() reimplementation

From: Andy Walls
Date: Sat Jul 21 2012 - 13:16:24 EST


On Thu, 2012-07-19 at 14:15 -0700, Tejun Heo wrote:
> From c9bba34243a86fb3ac82d1bdd0ce4bf796b79559 Mon Sep 17 00:00:00 2001
> From: Tejun Heo <tj@xxxxxxxxxx>
> Date: Thu, 19 Jul 2012 13:52:53 -0700
>
> Make the following two non-functional changes.
>
> * Separate out insert_kthread_work() from queue_kthread_work().
>
> * Relocate struct kthread_flush_work and kthread_flush_work_fn()
> definitions above flush_kthread_work().
>
> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> ---
> kernel/kthread.c | 40 ++++++++++++++++++++++++----------------
> 1 files changed, 24 insertions(+), 16 deletions(-)
>
> diff --git a/kernel/kthread.c b/kernel/kthread.c
> index 3d3de63..7b8a678 100644
> --- a/kernel/kthread.c
> +++ b/kernel/kthread.c
> @@ -378,6 +378,17 @@ repeat:
> }
> EXPORT_SYMBOL_GPL(kthread_worker_fn);
>
> +/* insert @work before @pos in @worker */

Hi Tejun,

Would a comment that the caller should be holding worker->lock be useful
here? Anyway, comment or not:

Acked-by: Andy Walls <awall@xxxxxxxxxxxxxxxx>

Regards,
Andy

> +static void insert_kthread_work(struct kthread_worker *worker,
> + struct kthread_work *work,
> + struct list_head *pos)
> +{
> + list_add_tail(&work->node, pos);
> + work->queue_seq++;
> + if (likely(worker->task))
> + wake_up_process(worker->task);
> +}
> +
> /**
> * queue_kthread_work - queue a kthread_work
> * @worker: target kthread_worker
> @@ -395,10 +406,7 @@ bool queue_kthread_work(struct kthread_worker *worker,
>
> spin_lock_irqsave(&worker->lock, flags);
> if (list_empty(&work->node)) {
> - list_add_tail(&work->node, &worker->work_list);
> - work->queue_seq++;
> - if (likely(worker->task))
> - wake_up_process(worker->task);
> + insert_kthread_work(worker, work, &worker->work_list);
> ret = true;
> }
> spin_unlock_irqrestore(&worker->lock, flags);
> @@ -406,6 +414,18 @@ bool queue_kthread_work(struct kthread_worker *worker,
> }
> EXPORT_SYMBOL_GPL(queue_kthread_work);
>
> +struct kthread_flush_work {
> + struct kthread_work work;
> + struct completion done;
> +};
> +
> +static void kthread_flush_work_fn(struct kthread_work *work)
> +{
> + struct kthread_flush_work *fwork =
> + container_of(work, struct kthread_flush_work, work);
> + complete(&fwork->done);
> +}
> +
> /**
> * flush_kthread_work - flush a kthread_work
> * @work: work to flush
> @@ -436,18 +456,6 @@ void flush_kthread_work(struct kthread_work *work)
> }
> EXPORT_SYMBOL_GPL(flush_kthread_work);
>
> -struct kthread_flush_work {
> - struct kthread_work work;
> - struct completion done;
> -};
> -
> -static void kthread_flush_work_fn(struct kthread_work *work)
> -{
> - struct kthread_flush_work *fwork =
> - container_of(work, struct kthread_flush_work, work);
> - complete(&fwork->done);
> -}
> -
> /**
> * flush_kthread_worker - flush all current works on a kthread_worker
> * @worker: worker to flush


--
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/