block: improve logic around when to sort a plug list

Only do it if we have requests for multiple queues in the same
plug.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 02732cae6080..08d940f85fa0 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1131,6 +1131,7 @@ struct blk_plug {
         struct list_head mq_list; /* blk-mq requests */
         struct list_head cb_list; /* md requires an unplug callback */
         unsigned short rq_count;
+        bool multiple_queues;
 };
 #define BLK_MAX_REQUEST_COUNT 16
 #define BLK_PLUG_FLUSH_SIZE (128 * 1024)