block: remove 'magic' from struct blk_plug

I don't think we've ever caught any bugs with this, and there's the
list poisoning for the plug lists to catch uninitialized cases.
So remove the magic member and save 8 bytes in the struct.

Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 913f1c2d3be0..098304576d51 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1060,7 +1060,6 @@ static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
  * schedule() where blk_schedule_flush_plug() is called.
  */
 struct blk_plug {
-        unsigned long magic; /* detect uninitialized use-cases */
         struct list_head list; /* requests */
         struct list_head mq_list; /* blk-mq requests */
         struct list_head cb_list; /* md requires an unplug callback */