From 229a92873f3afc20b0d91aaaec08cbc11689dd8b Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Fri, 14 Apr 2017 00:59:59 -0700 Subject: [PATCH] blk-mq: add shallow depth option for blk_mq_get_tag() Wire up the sbitmap_get_shallow() operation to the tag code so that a caller can limit the number of tags available to it. Signed-off-by: Omar Sandoval Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 5 ++++- block/blk-mq.h | 1 + 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 9d97bfc4d465..d0be72ccb091 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -96,7 +96,10 @@ static int __blk_mq_get_tag(struct blk_mq_alloc_data *data, if (!(data->flags & BLK_MQ_REQ_INTERNAL) && !hctx_may_queue(data->hctx, bt)) return -1; - return __sbitmap_queue_get(bt); + if (data->shallow_depth) + return __sbitmap_queue_get_shallow(bt, data->shallow_depth); + else + return __sbitmap_queue_get(bt); } unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) diff --git a/block/blk-mq.h b/block/blk-mq.h index 7e6f2e467696..524f44742816 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -141,6 +141,7 @@ struct blk_mq_alloc_data { /* input parameter */ struct request_queue *q; unsigned int flags; + unsigned int shallow_depth; /* input & output parameter */ struct blk_mq_ctx *ctx; -- 2.20.1