From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Jens Axboe To: , CC: , Jens Axboe Subject: [PATCH 2/2] blk-mq: add flag for drivers wanting blocking ->queue_rq() Date: Thu, 22 Sep 2016 08:53:00 -0600 Message-ID: <1474555980-2787-3-git-send-email-axboe@fb.com> In-Reply-To: <1474555980-2787-1-git-send-email-axboe@fb.com> References: <1474555980-2787-1-git-send-email-axboe@fb.com> MIME-Version: 1.0 Content-Type: text/plain List-ID: If a driver sets BLK_MQ_F_BLOCKING, it is allowed to block in its ->queue_rq() handler. For that case, blk-mq ensures that we always calls it from a safe context. Signed-off-by: Jens Axboe --- block/blk-mq.c | 2 +- include/linux/blk-mq.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index c29700010b5c..eae2f12f011f 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -908,7 +908,7 @@ void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) !blk_mq_hw_queue_mapped(hctx))) return; - if (!async) { + if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) { int cpu = get_cpu(); if (cpumask_test_cpu(cpu, hctx->cpumask)) { __blk_mq_run_hw_queue(hctx); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index fbcfdf323243..5daa0ef756dd 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -155,6 +155,7 @@ enum { BLK_MQ_F_TAG_SHARED = 1 << 1, BLK_MQ_F_SG_MERGE = 1 << 2, BLK_MQ_F_DEFER_ISSUE = 1 << 4, + BLK_MQ_F_BLOCKING = 1 << 5, BLK_MQ_F_ALLOC_POLICY_START_BIT = 8, BLK_MQ_F_ALLOC_POLICY_BITS = 1, -- 2.7.4