Avoid that it can take 200 ms too long to wait for requests to
finish. Note: blk_mq_freeze_queue() uses a wait queue to wait
for ongoing requests to finish.
Signed-off-by: Bart Van Assche <bart.vanass...@wdc.com>
Cc: Martin K. Petersen <martin.peter...@oracle.com>
Cc: Ming Lei <ming....@redhat.com>
Cc: Christoph Hellwig <h...@lst.de>
Cc: Hannes Reinecke <h...@suse.com>
Cc: Johannes Thumshirn <jthumsh...@suse.de>
---
drivers/scsi/scsi_lib.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index ca84fd2d93ea..c5e66bb0c94d 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2939,10 +2939,20 @@ scsi_device_quiesce(struct scsi_device *sdev)
if (err)
return err;
- scsi_run_queue(q);
- while (atomic_read(&sdev->device_busy)) {
- msleep_interruptible(200);
+ if (q->mq_ops) {
+ /*
+ * Ensure write order of the PREEMPT_ONLY queue flag and
+ * q_usage_counter. See also blk_queue_enter().
+ */
+ smp_wmb();
+ blk_mq_freeze_queue(q);
+ blk_mq_unfreeze_queue(q);
+ } else {
scsi_run_queue(q);
+ while (atomic_read(&sdev->device_busy)) {
+ msleep_interruptible(200);
+ scsi_run_queue(q);
+ }
}
return 0;
}
--
2.14.1
