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| author | Jens Axboe <axboe@kernel.dk> | 2021-10-09 13:10:39 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-10-18 06:17:35 -0600 |
| commit | 349302da83529539040d2516de1deec1e09f491c (patch) | |
| tree | 3d8049f24e9c7f2c32ef7ae88322d6828d50af59 /block/blk-mq-tag.h | |
| parent | 9672b0d43782047b1825a96bafee1b6aefa35bc2 (diff) | |
block: improve batched tag allocation
Add a blk_mq_get_tags() helper, which uses the new sbitmap API for
allocating a batch of tags all at once. This both simplifies the block
code for batched allocation, and it is also more efficient than just
doing repeated calls into __sbitmap_queue_get().
This reduces the sbitmap overhead in peak runs from ~3% to ~1% and
yields a performanc increase from 6.6M IOPS to 6.8M IOPS for a single
CPU core.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq-tag.h')
| -rw-r--r-- | block/blk-mq-tag.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index d8ce89fa1686..71c2f7d8e9b7 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -38,6 +38,8 @@ extern int blk_mq_init_bitmaps(struct sbitmap_queue *bitmap_tags, int node, int alloc_policy); extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data); +unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags, + unsigned int *offset); extern void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx, unsigned int tag); extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, |