Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4d92a9be authored by Jens Axboe's avatar Jens Axboe
Browse files

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: default avatarJens Axboe <axboe@fb.com>
parent cdef54dd

block/blk-core.c

+0 −5
Original line number Diff line number Diff line
@@ -2957,8 +2957,6 @@ int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, 
}

EXPORT_SYMBOL(kblockd_schedule_delayed_work_on);



#define PLUG_MAGIC	0x91827364



/**

 * blk_start_plug - initialize blk_plug and track it inside the task_struct

 * @plug:	The &struct blk_plug that needs to be initialized
@@ -2977,7 +2975,6 @@ void blk_start_plug(struct blk_plug *plug) 
{

	struct task_struct *tsk = current;



	plug->magic = PLUG_MAGIC;

	INIT_LIST_HEAD(&plug->list);

	INIT_LIST_HEAD(&plug->mq_list);

	INIT_LIST_HEAD(&plug->cb_list);
@@ -3074,8 +3071,6 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) 
	LIST_HEAD(list);

	unsigned int depth;



	BUG_ON(plug->magic != PLUG_MAGIC);



	flush_plug_callbacks(plug, from_schedule);



	if (!list_empty(&plug->mq_list))

include/linux/blkdev.h

+0 −1
Original line number Diff line number Diff line
@@ -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 */