From 36e3cf273977da34a760d513e1bef8431a9abaa0 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Fri, 7 Apr 2017 11:16:53 -0700 Subject: [PATCH] scsi: Avoid that SCSI queues get stuck If a .queue_rq() function returns BLK_MQ_RQ_QUEUE_BUSY then the block driver that implements that function is responsible for rerunning the hardware queue once requests can be queued again successfully. commit 52d7f1b5c2f3 ("blk-mq: Avoid that requeueing starts stopped queues") removed the blk_mq_stop_hw_queue() call from scsi_queue_rq() for the BLK_MQ_RQ_QUEUE_BUSY case. Hence change all calls to functions that are intended to rerun a busy queue such that these examine all hardware queues instead of only stopped queues. Since no other functions than scsi_internal_device_block() and scsi_internal_device_unblock() should ever stop or restart a SCSI queue, change the blk_mq_delay_queue() call into a blk_mq_delay_run_hw_queue() call. Fixes: commit 52d7f1b5c2f3 ("blk-mq: Avoid that requeueing starts stopped queues") Fixes: commit 7e79dadce222 ("blk-mq: stop hardware queue in blk_mq_delay_queue()") Signed-off-by: Bart Van Assche Cc: Martin K. Petersen Cc: James Bottomley Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Sagi Grimberg Cc: Long Li Cc: K. Y. Srinivasan Signed-off-by: Jens Axboe --- drivers/scsi/scsi_lib.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 19125d72f322..e5a2d590a104 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -496,7 +496,7 @@ static void scsi_run_queue(struct request_queue *q) scsi_starved_list_run(sdev->host); if (q->mq_ops) - blk_mq_start_stopped_hw_queues(q, false); + blk_mq_run_hw_queues(q, false); else blk_run_queue(q); } @@ -667,7 +667,7 @@ static bool scsi_end_request(struct request *req, int error, !list_empty(&sdev->host->starved_list)) kblockd_schedule_work(&sdev->requeue_work); else - blk_mq_start_stopped_hw_queues(q, true); + blk_mq_run_hw_queues(q, true); } else { unsigned long flags; @@ -1974,7 +1974,7 @@ out: case BLK_MQ_RQ_QUEUE_BUSY: if (atomic_read(&sdev->device_busy) == 0 && !scsi_device_blocked(sdev)) - blk_mq_delay_queue(hctx, SCSI_QUEUE_DELAY); + blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY); break; case BLK_MQ_RQ_QUEUE_ERROR: /* -- 2.20.1