diff options
| author | Ming Lei <ming.lei@redhat.com> | 2025-05-05 22:17:58 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-05-06 07:43:43 -0600 |
| commit | 21eed794ab4bd1a6c82a55df4416d18fb4d21da9 (patch) | |
| tree | 4e3247f892a8c34f3d2058e2a39b81d864890ea1 /include/linux/blkdev.h | |
| parent | 5c3d858cdc57196e6d438e5ad47a732216e81a9c (diff) | |
block: add new helper for disabling elevator switch when deleting disk
Add new helper disable_elv_switch() and new flag QUEUE_FLAG_NO_ELV_SWITCH
for disabling elevator switch before deleting disk:
- originally flag QUEUE_FLAG_REGISTERED is added for preventing elevator
switch during removing disk, but this flag has been used widely for
other purposes, so add one new flag for disabling elevator switch only
- for avoiding deadlock risk, we have to move elevator queue
register/unregister out of elevator lock and queue freeze, which will be
done in next patch. However, this way adds small race window between elevator
switch and deleting ->queue_kobj, in which elevator queue register/unregister
could be run concurrently. The added helper will be used for avoiding the race
in the following patch.
- drain in-progress elevator switch before deleting disk
Suggested-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250505141805.2751237-21-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux/blkdev.h')
| -rw-r--r-- | include/linux/blkdev.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c36d7a1c2cc0..3aa1fd637d57 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -642,6 +642,7 @@ enum { QUEUE_FLAG_HCTX_ACTIVE, /* at least one blk-mq hctx is active */ QUEUE_FLAG_SQ_SCHED, /* single queue style io dispatch */ QUEUE_FLAG_DISABLE_WBT_DEF, /* for sched to disable/enable wbt */ + QUEUE_FLAG_NO_ELV_SWITCH, /* can't switch elevator any more */ QUEUE_FLAG_MAX }; @@ -679,6 +680,8 @@ void blk_queue_flag_clear(unsigned int flag, struct request_queue *q); ((q)->limits.features & BLK_FEAT_SKIP_TAGSET_QUIESCE) #define blk_queue_disable_wbt(q) \ test_bit(QUEUE_FLAG_DISABLE_WBT_DEF, &(q)->queue_flags) +#define blk_queue_no_elv_switch(q) \ + test_bit(QUEUE_FLAG_NO_ELV_SWITCH, &(q)->queue_flags) extern void blk_set_pm_only(struct request_queue *q); extern void blk_clear_pm_only(struct request_queue *q); |