diff mbox

[10/12] SRP transport, scsi-mq: Wait for .queue_rq() if necessary

Message ID 0cd77719-1f11-d5c3-3186-1c7c3cfd6886@sandisk.com (mailing list archive)
State New, archived
Headers show

Commit Message

Bart Van Assche Oct. 26, 2016, 10:55 p.m. UTC 
Ensure that if scsi-mq is enabled that scsi_wait_for_queuecommand()
waits until ongoing shost->hostt->queuecommand() calls have finished.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: James Bottomley <jejb@linux.vnet.ibm.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Doug Ledford <dledford@redhat.com>
---
 drivers/scsi/scsi_lib.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

Comments

Johannes Thumshirn Oct. 27, 2016, 8:27 a.m. UTC | #1 
On Wed, Oct 26, 2016 at 03:55:34PM -0700, Bart Van Assche wrote:
> Ensure that if scsi-mq is enabled that scsi_wait_for_queuecommand()
> waits until ongoing shost->hostt->queuecommand() calls have finished.
> 
> Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Sagi Grimberg Oct. 27, 2016, 12:19 p.m. UTC | #2 
Thanks for moving it,

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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diff mbox

Patch

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index c1561e7..9b8b19e 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2724,8 +2724,6 @@  EXPORT_SYMBOL_GPL(sdev_evt_send_simple);
 /**
  * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn()
  * @shost: SCSI host for which to count the number of scsi_request_fn() callers.
- *
- * To do: add support for scsi-mq in this function.
  */
 static int scsi_request_fn_active(struct Scsi_Host *shost)
 {
@@ -2744,12 +2742,20 @@  static int scsi_request_fn_active(struct Scsi_Host *shost)
 	return request_fn_active;
 }
 
+static void scsi_mq_wait_for_queuecommand(struct Scsi_Host *shost)
+{
+	struct scsi_device *sdev;
+
+	shost_for_each_device(sdev, shost)
+		blk_mq_quiesce_queue(sdev->request_queue);
+}
+
 /**
  * scsi_wait_for_queuecommand() - wait for ongoing queuecommand() calls
  * @shost: SCSI host pointer.
  *
  * Wait until the ongoing shost->hostt->queuecommand() calls that are
- * invoked from scsi_request_fn() have finished.
+ * invoked from either scsi_request_fn() or scsi_queue_rq() have finished.
  *
  * To do: avoid that scsi_send_eh_cmnd() calls queuecommand() after
  * scsi_internal_device_block() has blocked a SCSI device and remove and also
@@ -2757,8 +2763,12 @@  static int scsi_request_fn_active(struct Scsi_Host *shost)
  */
 void scsi_wait_for_queuecommand(struct Scsi_Host *shost)
 {
-	while (scsi_request_fn_active(shost))
-		msleep(20);
+	if (shost->use_blk_mq) {
+		scsi_mq_wait_for_queuecommand(shost);
+	} else {
+		while (scsi_request_fn_active(shost))
+			msleep(20);
+	}
 }
 EXPORT_SYMBOL(scsi_wait_for_queuecommand);