It is nontrivial to derive from the blk-mq source code when
blk_mq_tags.active_queues is decremented. Hence add a comment that
explains this.
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
---
block/blk-mq.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f84d145490bf..b86d2cafc355 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -834,6 +834,10 @@ static void blk_mq_timeout_work(struct work_struct *work)
} else {
struct blk_mq_hw_ctx *hctx;
+ /*
+ * All requests finished (latest request timeout) seconds ago,
+ * so mark each hctx as idle.
+ */
queue_for_each_hw_ctx(q, hctx, i) {
/* the hctx may be unmapped, so check it here */
if (blk_mq_hw_queue_mapped(hctx))
--
2.14.0
