Re: 2.4.20: Proccess stuck in __lock_page ...

[manish]

Andrew Morton wrote:

>Matthias Mueller <[e-mail]> wrote:
>
>>Works fine on my notebook. Good throughput and no mouse hangs anymore.
>>
>
>Interesting.
>
>Could you please work out which change caused it?  Go back to stock 2.4 and
>then apply this:
>
>
>diff -puN drivers/block/ll_rw_blk.c~1 drivers/block/ll_rw_blk.c
>--- 24/drivers/block/ll_rw_blk.c~1	2003-05-28 03:20:42.000000000 -0700
>+++ 24-akpm/drivers/block/ll_rw_blk.c	2003-05-28 03:20:57.000000000 -0700
>@@ -590,10 +590,10 @@ static struct request *__get_request_wai
> 	register struct request *rq;
> 	DECLARE_WAITQUEUE(wait, current);
> 
>-	generic_unplug_device(q);
> 	add_wait_queue_exclusive(&q->wait_for_requests[rw], &wait);
> 	do {
> 		set_current_state(TASK_UNINTERRUPTIBLE);
>+		generic_unplug_device(q);
> 		if (q->rq[rw].count == 0)
> 			schedule();
> 		spin_lock_irq(&io_request_lock);
>
>
>
>then this:
>
>diff -puN drivers/block/ll_rw_blk.c~2 drivers/block/ll_rw_blk.c
>--- 24/drivers/block/ll_rw_blk.c~2	2003-05-28 03:21:03.000000000 -0700
>+++ 24-akpm/drivers/block/ll_rw_blk.c	2003-05-28 03:21:09.000000000 -0700
>@@ -590,7 +590,7 @@ static struct request *__get_request_wai
> 	register struct request *rq;
> 	DECLARE_WAITQUEUE(wait, current);
> 
>-	add_wait_queue_exclusive(&q->wait_for_requests[rw], &wait);
>+	add_wait_queue(&q->wait_for_requests[rw], &wait);
> 	do {
> 		set_current_state(TASK_UNINTERRUPTIBLE);
> 		generic_unplug_device(q);
>
>
>Then this (totally unlikely, don't bother):
>
>diff -puN drivers/block/ll_rw_blk.c~3 drivers/block/ll_rw_blk.c
>--- 24/drivers/block/ll_rw_blk.c~3	2003-05-28 03:21:15.000000000 -0700
>+++ 24-akpm/drivers/block/ll_rw_blk.c	2003-05-28 03:21:39.000000000 -0700
>@@ -829,8 +829,7 @@ void blkdev_release_request(struct reque
> 	 */
> 	if (q) {
> 		list_add(&req->queue, &q->rq[rw].free);
>-		if (++q->rq[rw].count >= q->batch_requests &&
>-				waitqueue_active(&q->wait_for_requests[rw]))
>+		if (++q->rq[rw].count >= q->batch_requests)
> 			wake_up(&q->wait_for_requests[rw]);
> 	}
> }
>
>_
>
Hello !

I have applied patch 1+2+3 and it seemed to have solved the 
stalls/pauses that I was seeing with the stock kernel after long hrs of 
test using bonnie.

Thanks much
Manish