block: cache request queue in bdev
There are tons of places where we need to get a request_queue only
having bdev, which turns into bdev->bd_disk->queue. There are probably a
hundred of such places considering inline helpers, and enough of them
are in hot paths.
Cache queue pointer in struct block_device and make use of it in
bdev_get_queue().
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a3bfaecdd28956f03629d0ca5c63ebc096e1c809.1634219547.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/genhd.c b/block/genhd.c
index ffbdb9b..d148c38 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1267,6 +1267,9 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
if (!disk->bdi)
goto out_free_disk;
+ /* bdev_alloc() might need the queue, set before the first call */
+ disk->queue = q;
+
disk->part0 = bdev_alloc(disk, 0);
if (!disk->part0)
goto out_free_bdi;
@@ -1282,7 +1285,6 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
disk_to_dev(disk)->type = &disk_type;
device_initialize(disk_to_dev(disk));
inc_diskseq(disk);
- disk->queue = q;
q->disk = disk;
lockdep_init_map(&disk->lockdep_map, "(bio completion)", lkclass, 0);
#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
