From cf4b50afc28cc4629f82f5591bef1db2ce129fdc Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 9 May 2014 14:54:08 -0600 Subject: [PATCH] blk-mq: fix race in IO start accounting Commit c6d600c6 opened up a small race where we could attempt to account IO completion on a request, racing with IO start accounting. Fix this up by ensuring that we've accounted for IO start before inserting the request. Signed-off-by: Jens Axboe --- block/blk-mq.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 9f07a266f7ab..526feee31bff 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1088,17 +1088,15 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio) } if (!(hctx->flags & BLK_MQ_F_SHOULD_MERGE)) { - init_request_from_bio(rq, bio); - + blk_mq_bio_to_request(rq, bio); spin_lock(&ctx->lock); insert_rq: __blk_mq_insert_request(hctx, rq, false); spin_unlock(&ctx->lock); - blk_account_io_start(rq, 1); } else { spin_lock(&ctx->lock); if (!blk_mq_attempt_merge(q, ctx, bio)) { - init_request_from_bio(rq, bio); + blk_mq_bio_to_request(rq, bio); goto insert_rq; } -- GitLab