diff options
| author | Jan Kara <jack@suse.cz> | 2014-02-24 16:39:54 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2014-02-24 14:46:42 -0800 |
| commit | 6d113398dcf4dfcd9787a4ead738b186f7b7ff0f (patch) | |
| tree | 6d49945269bf454cf1682890d1f10789f23ca26d | |
| parent | d9a74df512e44580a34bf6e70f5d08c126507354 (diff) | |
| download | linux-6d113398dcf4dfcd9787a4ead738b186f7b7ff0f.tar.bz2 | |
block: Stop abusing rq->csd.list in blk-softirq
Abusing rq->csd.list for a list of requests to complete is rather ugly.
We use rq->queuelist instead which is much cleaner. It is safe because
queuelist is used by the block layer only for requests waiting to be
submitted to a device. Thus it is unused when irq reports the request IO
is finished.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | block/blk-softirq.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/block/blk-softirq.c b/block/blk-softirq.c index 57790c1a97eb..b5c37d96cf0e 100644 --- a/block/blk-softirq.c +++ b/block/blk-softirq.c @@ -30,8 +30,8 @@ static void blk_done_softirq(struct softirq_action *h) while (!list_empty(&local_list)) { struct request *rq; - rq = list_entry(local_list.next, struct request, csd.list); - list_del_init(&rq->csd.list); + rq = list_entry(local_list.next, struct request, queuelist); + list_del_init(&rq->queuelist); rq->q->softirq_done_fn(rq); } } @@ -45,9 +45,14 @@ static void trigger_softirq(void *data) local_irq_save(flags); list = this_cpu_ptr(&blk_cpu_done); - list_add_tail(&rq->csd.list, list); + /* + * We reuse queuelist for a list of requests to process. Since the + * queuelist is used by the block layer only for requests waiting to be + * submitted to the device it is unused now. + */ + list_add_tail(&rq->queuelist, list); - if (list->next == &rq->csd.list) + if (list->next == &rq->queuelist) raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_restore(flags); @@ -136,7 +141,7 @@ void __blk_complete_request(struct request *req) struct list_head *list; do_local: list = this_cpu_ptr(&blk_cpu_done); - list_add_tail(&req->csd.list, list); + list_add_tail(&req->queuelist, list); /* * if the list only contains our just added request, @@ -144,7 +149,7 @@ do_local: * entries there, someone already raised the irq but it * hasn't run yet. */ - if (list->next == &req->csd.list) + if (list->next == &req->queuelist) raise_softirq_irqoff(BLOCK_SOFTIRQ); } else if (raise_blk_irq(ccpu, req)) goto do_local; |