diff options
Diffstat (limited to 'block/blk-core.c')
| -rw-r--r-- | block/blk-core.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index fd4749391e1..6804fdf27ef 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -771,9 +771,12 @@ static struct request *get_request(struct request_queue *q, int rw_flags, { struct request *rq = NULL; struct request_list *rl = &q->rq; - struct io_context *ioc = NULL; + struct io_context *ioc; const bool is_sync = rw_is_sync(rw_flags) != 0; + bool retried = false; int may_queue; +retry: + ioc = current->io_context; if (unlikely(blk_queue_dead(q))) return NULL; @@ -784,7 +787,20 @@ static struct request *get_request(struct request_queue *q, int rw_flags, if (rl->count[is_sync]+1 >= queue_congestion_on_threshold(q)) { if (rl->count[is_sync]+1 >= q->nr_requests) { - ioc = current_io_context(GFP_ATOMIC, q->node); + /* + * We want ioc to record batching state. If it's + * not already there, creating a new one requires + * dropping queue_lock, which in turn requires + * retesting conditions to avoid queue hang. + */ + if (!ioc && !retried) { + spin_unlock_irq(q->queue_lock); + create_io_context(current, gfp_mask, q->node); + spin_lock_irq(q->queue_lock); + retried = true; + goto retry; + } + /* * The queue will fill after this allocation, so set * it as full, and mark this process as "batching". @@ -892,7 +908,6 @@ static struct request *get_request_wait(struct request_queue *q, int rw_flags, rq = get_request(q, rw_flags, bio, GFP_NOIO); while (!rq) { DEFINE_WAIT(wait); - struct io_context *ioc; struct request_list *rl = &q->rq; if (unlikely(blk_queue_dead(q))) @@ -912,8 +927,8 @@ static struct request *get_request_wait(struct request_queue *q, int rw_flags, * up to a big batch of them for a small period time. * See ioc_batching, ioc_set_batching */ - ioc = current_io_context(GFP_NOIO, q->node); - ioc_set_batching(q, ioc); + create_io_context(current, GFP_NOIO, q->node); + ioc_set_batching(q, current->io_context); spin_lock_irq(q->queue_lock); finish_wait(&rl->wait[is_sync], &wait); |