OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

block: drain queue before waiting for q_usage_counter becoming zero 

Now we track legacy requests with .q_usage_counter in commit 055f6e18e0
("block: Make q_usage_counter also track legacy requests"), but that
commit never runs and drains legacy queue before waiting for this counter
becoming zero, then IO hang is caused in the test of pulling disk during IO.

This patch fixes the issue by draining requests before waiting for
q_usage_counter becoming zero, both Mauricio and chenxiang reported this
issue, and observed that it can be fixed by this patch.

Link: https://marc.info/?l=linux-block&m=151192424731797&w=2
Fixes: 055f6e18e08f("block: Make q_usage_counter also track legacy requests")
Cc: Wen Xiong <wenxiong@us.ibm.com>
Tested-by: "chenxiang (M)" <chenxiang66@hisilicon.com>
Tested-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Ming Lei 2017-11-30 07:56:35 +08:00 committed by Jens Axboe
parent 6d0e4827b7
commit 454be724f6
3 changed files with 11 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
block/blk-core.c
View File

@ -562,6 +562,13 @@ static void __blk_drain_queue(struct request_queue *q, bool drain_all)
}
}
void blk_drain_queue(struct request_queue *q)
{
spin_lock_irq(q->queue_lock);
__blk_drain_queue(q, true);
spin_unlock_irq(q->queue_lock);
}
/**
* blk_queue_bypass_start - enter queue bypass mode
* @q: queue of interest
@ -689,8 +696,6 @@ void blk_cleanup_queue(struct request_queue *q)
*/
blk_freeze_queue(q);
spin_lock_irq(lock);
if (!q->mq_ops)
__blk_drain_queue(q, true);
queue_flag_set(QUEUE_FLAG_DEAD, q);
spin_unlock_irq(lock);

2
block/blk-mq.c
View File

@ -161,6 +161,8 @@ void blk_freeze_queue(struct request_queue *q)
* exported to drivers as the only user for unfreeze is blk_mq.
*/
blk_freeze_queue_start(q);
if (!q->mq_ops)
blk_drain_queue(q);
blk_mq_freeze_queue_wait(q);
}

2
block/blk.h
View File

@ -330,4 +330,6 @@ static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
}
#endif /* CONFIG_BOUNCE */
extern void blk_drain_queue(struct request_queue *q);
#endif /* BLK_INTERNAL_H */