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| author | Christoph Hellwig <hch@lst.de> | 2015-10-30 20:57:30 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-12-22 09:38:16 -0700 |
| commit | 287922eb0b186e2a5bf54fdd04b734c25c90035c (patch) | |
| tree | bf7e8976139ac3eacfaab6ace9d1807088463140 /block/blk-mq.c | |
| parent | 8c0b39155048d5a24f25c6c60aa83729927b04cd (diff) | |
| download | linux-287922eb0b186e2a5bf54fdd04b734c25c90035c.tar.gz linux-287922eb0b186e2a5bf54fdd04b734c25c90035c.tar.bz2 linux-287922eb0b186e2a5bf54fdd04b734c25c90035c.zip | |
block: defer timeouts to a workqueue
Timer context is not very useful for drivers to perform any meaningful abort
action from. So instead of calling the driver from this useless context
defer it to a workqueue as soon as possible.
Note that while a delayed_work item would seem the right thing here I didn't
dare to use it due to the magic in blk_add_timer that pokes deep into timer
internals. But maybe this encourages Tejun to add a sensible API for that to
the workqueue API and we'll all be fine in the end :)
Contains a major update from Keith Bush:
"This patch removes synchronizing the timeout work so that the timer can
start a freeze on its own queue. The timer enters the queue, so timer
context can only start a freeze, but not wait for frozen."
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block/blk-mq.c')
| -rw-r--r-- | block/blk-mq.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 93a4e1956915..9cb2894840ab 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -615,15 +615,19 @@ static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, } } -static void blk_mq_rq_timer(unsigned long priv) +static void blk_mq_timeout_work(struct work_struct *work) { - struct request_queue *q = (struct request_queue *)priv; + struct request_queue *q = + container_of(work, struct request_queue, timeout_work); struct blk_mq_timeout_data data = { .next = 0, .next_set = 0, }; int i; + if (blk_queue_enter(q, true)) + return; + blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &data); if (data.next_set) { @@ -638,6 +642,7 @@ static void blk_mq_rq_timer(unsigned long priv) blk_mq_tag_idle(hctx); } } + blk_queue_exit(q); } /* @@ -2015,7 +2020,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, hctxs[i]->queue_num = i; } - setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); + INIT_WORK(&q->timeout_work, blk_mq_timeout_work); blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); q->nr_queues = nr_cpu_ids; |