Re: [PATCH 2/4] blk-mq: introduce blk_mq_get_queue_depth()
From: Omar Sandoval <osandov@osandov.com>
Date: 2017-05-03 16:55:32
On Fri, Apr 28, 2017 at 11:15:37PM +0800, Ming Lei wrote:
The hardware queue depth can be resized via blk_mq_update_nr_requests(), so introduce this helper for retrieving queue's depth easily.
One nit below. If the per-hardware queue tag space situation changes, we can revisit this and the similar thing in Kyber. Reviewed-by: Omar Sandoval <redacted>
quoted hunk ↗ jump to hunk
Signed-off-by: Ming Lei <redacted> --- block/blk-mq.c | 12 ++++++++++++ block/blk-mq.h | 1 + 2 files changed, 13 insertions(+)diff --git a/block/blk-mq.c b/block/blk-mq.c index e530bc54f0d9..04761fb76ab4 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c@@ -2637,6 +2637,18 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set) } EXPORT_SYMBOL(blk_mq_free_tag_set); +/* + * Queue depth can be changed via blk_mq_update_nr_requests(), + * so use this helper to retrieve queue's depth. + */ +int blk_mq_get_queue_depth(struct request_queue *q) +{ + /* All queues have same queue depth */ + struct blk_mq_tags *tags = q->tag_set->tags[0];
Not sure what's going on with the spacing here. Tab instead of a space?
quoted hunk ↗ jump to hunk
+ return tags->bitmap_tags.sb.depth; +} + int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) { struct blk_mq_tag_set *set = q->tag_set;diff --git a/block/blk-mq.h b/block/blk-mq.h index 2814a14e529c..8085d5989cf5 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h@@ -166,6 +166,7 @@ void __blk_mq_finish_request(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, void blk_mq_finish_request(struct request *rq); struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data, unsigned int op); +int blk_mq_get_queue_depth(struct request_queue *q); static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx) {-- 2.9.3