Thread (31 messages) 31 messages, 8 authors, 2016-10-11

Re: [PATCH 4/9] block: Move blk_freeze_queue() and blk_unfreeze_queue() code

From: Hannes Reinecke <hare@suse.de>
Date: 2016-09-27 06:26:22
Also in: linux-nvme, linux-rdma, linux-scsi

On 09/26/2016 08:27 PM, Bart Van Assche wrote:
quoted hunk ↗ jump to hunk
Move the blk_freeze_queue() and blk_unfreeze_queue() implementations
from block/blk-mq.c to block/blk-core.c. Drop "_mq" from the name of
the functions that have been moved.

Signed-off-by: Bart Van Assche <redacted>
---
 block/blk-core.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 block/blk-mq.c   | 41 +++--------------------------------------
 block/blk.h      |  3 +++
 3 files changed, 51 insertions(+), 38 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index b75d688..8cc8006 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -682,6 +682,51 @@ static void blk_queue_usage_counter_release(struct percpu_ref *ref)
 	wake_up_all(&q->mq_freeze_wq);
 }
 
+void blk_freeze_queue_start(struct request_queue *q)
+{
+	int freeze_depth;
+
+	freeze_depth = atomic_inc_return(&q->mq_freeze_depth);
+	if (freeze_depth == 1) {
+		percpu_ref_kill(&q->q_usage_counter);
+		blk_mq_run_hw_queues(q, false);
+	}
+}
+
As you dropped the 'mq_' prefix, maybe you should rename the counter to
'freeze_depth', to?
And are you sure this works in the !mq case, too?
+void blk_freeze_queue_wait(struct request_queue *q)
+{
+	wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
+}
+
Same here, rename ->mq_freeze_wq to ->freeze_wq.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare@suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG Nürnberg)
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help