From a0235d230f3245aa4bd70b514d5effb24be61acd Mon Sep 17 00:00:00 2001 From: John Garry Date: Wed, 19 Aug 2020 23:20:25 +0800 Subject: blk-mq: Relocate hctx_may_queue() blk-mq.h and blk-mq-tag.h include on each other, which is less than ideal. Locate hctx_may_queue() to blk-mq.h, as it is not really tag specific code. In this way, we can drop the blk-mq-tag.h include of blk-mq.h Signed-off-by: John Garry Tested-by: Douglas Gilbert Signed-off-by: Jens Axboe --- block/blk-mq.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'block/blk-mq.h') diff --git a/block/blk-mq.h b/block/blk-mq.h index 3acdb56065e1..56dc37c21908 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -259,4 +259,36 @@ static inline struct blk_plug *blk_mq_plug(struct request_queue *q, return NULL; } +/* + * For shared tag users, we track the number of currently active users + * and attempt to provide a fair share of the tag depth for each of them. + */ +static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, + struct sbitmap_queue *bt) +{ + unsigned int depth, users; + + if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) + return true; + if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) + return true; + + /* + * Don't try dividing an ant + */ + if (bt->sb.depth == 1) + return true; + + users = atomic_read(&hctx->tags->active_queues); + if (!users) + return true; + + /* + * Allow at least some tags + */ + depth = max((bt->sb.depth + users - 1) / users, 4U); + return atomic_read(&hctx->nr_active) < depth; +} + + #endif -- cgit v1.2.3