Hi,
在 2025/04/19 0:36, Ming Lei 写道:
Move blk_mq_add_queue_tag_set() after blk_mq_map_swqueue(), and publish
this request queue to tagset after everything is setup.
This way is safe because BLK_MQ_F_TAG_QUEUE_SHARED isn't used by
blk_mq_map_swqueue(), and this flag is mainly checked in fast IO code
path.
Prepare for removing ->elevator_lock from blk_mq_map_swqueue() which
is supposed to be called when elevator switch isn't possible.
I think you mean *is* possible? Or to protect against switching
elevator concurrently?
Reported-by: Nilay Shroff <nilay@xxxxxxxxxxxxx>
Closes: https://lore.kernel.org/linux-block/567cb7ab-23d6-4cee-a915-c8cdac903ddd@xxxxxxxxxxxxx/
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-mq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index e0fe12f1320f..7cda919fafba 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -4561,8 +4561,8 @@ int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
q->nr_requests = set->queue_depth;
blk_mq_init_cpu_queues(q, set->nr_hw_queues);
- blk_mq_add_queue_tag_set(set, q);
blk_mq_map_swqueue(q);
+ blk_mq_add_queue_tag_set(set, q);
return 0;
err_hctxs:
