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| author | Ming Lei <ming.lei@redhat.com> | 2021-12-03 16:15:31 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-12-04 00:51:29 +0300 |
| commit | 2a904d00855f94cb85751e45fa494f225d44ae0d (patch) | |
| tree | 0bcc141b19e61b4d536115e274c68da183ae9ff2 /block/blk-mq.h | |
| parent | 0a467d0fdd9594fbb449ebc93852533332c528fd (diff) | |
| download | linux-2a904d00855f94cb85751e45fa494f225d44ae0d.tar.xz | |
blk-mq: remove hctx_lock and hctx_unlock
Remove hctx_lock and hctx_unlock, and add one helper of
blk_mq_run_dispatch_ops() to run code block defined in dispatch_ops
with rcu/srcu read held.
Compared with hctx_lock()/hctx_unlock():
1) remove 2 branch to 1, so we just need to check
(hctx->flags & BLK_MQ_F_BLOCKING) once when running one dispatch_ops
2) srcu_idx needn't to be touched in case of non-blocking
3) might_sleep_if() can be moved to the blocking branch
Also put the added blk_mq_run_dispatch_ops() in private header, so that
the following patch can use it out of blk-mq.c.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211203131534.3668411-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq.h')
| -rw-r--r-- | block/blk-mq.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/block/blk-mq.h b/block/blk-mq.h index d516c7a46f57..e4c396204928 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -374,5 +374,21 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, return __blk_mq_active_requests(hctx) < depth; } +/* run the code block in @dispatch_ops with rcu/srcu read lock held */ +#define blk_mq_run_dispatch_ops(hctx, dispatch_ops) \ +do { \ + if (!((hctx)->flags & BLK_MQ_F_BLOCKING)) { \ + rcu_read_lock(); \ + (dispatch_ops); \ + rcu_read_unlock(); \ + } else { \ + int srcu_idx; \ + \ + might_sleep(); \ + srcu_idx = srcu_read_lock((hctx)->srcu); \ + (dispatch_ops); \ + srcu_read_unlock((hctx)->srcu, srcu_idx); \ + } \ +} while (0) #endif |