If we are issuing a list of requests, we know if we're at the last one. If we fail issuing, ensure that we call ->commits_rqs() to flush any potential previous requests.
Signed-off-by: Jens Axboe <[email protected]> --- block/blk-core.c | 2 +- block/blk-mq.c | 32 ++++++++++++++++++++++++-------- block/blk-mq.h | 2 +- 3 files changed, 26 insertions(+), 10 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index c9758d185357..808a65d23f1a 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1334,7 +1334,7 @@ blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request * * bypass a potential scheduler on the bottom device for * insert. */ - return blk_mq_request_issue_directly(rq); + return blk_mq_request_issue_directly(rq, true); } EXPORT_SYMBOL_GPL(blk_insert_cloned_request); diff --git a/block/blk-mq.c b/block/blk-mq.c index 6a249bf6ed00..0a12cec0b426 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1260,6 +1260,14 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, if (!list_empty(list)) { bool needs_restart; + /* + * If we didn't flush the entire list, we could have told + * the driver there was more coming, but that turned out to + * be a lie. + */ + if (q->mq_ops->commit_rqs) + q->mq_ops->commit_rqs(hctx); + spin_lock(&hctx->lock); list_splice_init(list, &hctx->dispatch); spin_unlock(&hctx->lock); @@ -1736,12 +1744,12 @@ static blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq) static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, struct request *rq, - blk_qc_t *cookie) + blk_qc_t *cookie, bool last) { struct request_queue *q = rq->q; struct blk_mq_queue_data bd = { .rq = rq, - .last = true, + .last = last, }; blk_qc_t new_cookie; blk_status_t ret; @@ -1776,7 +1784,7 @@ static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, struct request *rq, blk_qc_t *cookie, - bool bypass_insert) + bool bypass_insert, bool last) { struct request_queue *q = rq->q; bool run_queue = true; @@ -1805,7 +1813,7 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, goto insert; } - return __blk_mq_issue_directly(hctx, rq, cookie); + return __blk_mq_issue_directly(hctx, rq, cookie, last); insert: if (bypass_insert) return BLK_STS_RESOURCE; @@ -1824,7 +1832,7 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, hctx_lock(hctx, &srcu_idx); - ret = __blk_mq_try_issue_directly(hctx, rq, cookie, false); + ret = __blk_mq_try_issue_directly(hctx, rq, cookie, false, true); if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) blk_mq_sched_insert_request(rq, false, true, false); else if (ret != BLK_STS_OK) @@ -1833,7 +1841,7 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, hctx_unlock(hctx, srcu_idx); } -blk_status_t blk_mq_request_issue_directly(struct request *rq) +blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last) { blk_status_t ret; int srcu_idx; @@ -1841,7 +1849,7 @@ blk_status_t blk_mq_request_issue_directly(struct request *rq) struct blk_mq_hw_ctx *hctx = rq->mq_hctx; hctx_lock(hctx, &srcu_idx); - ret = __blk_mq_try_issue_directly(hctx, rq, &unused_cookie, true); + ret = __blk_mq_try_issue_directly(hctx, rq, &unused_cookie, true, last); hctx_unlock(hctx, srcu_idx); return ret; @@ -1856,7 +1864,7 @@ void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, queuelist); list_del_init(&rq->queuelist); - ret = blk_mq_request_issue_directly(rq); + ret = blk_mq_request_issue_directly(rq, list_empty(list)); if (ret != BLK_STS_OK) { if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) { @@ -1866,6 +1874,14 @@ void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, blk_mq_end_request(rq, ret); } } + + /* + * If we didn't flush the entire list, we could have told + * the driver there was more coming, but that turned out to + * be a lie. + */ + if (!list_empty(list) && hctx->queue->mq_ops->commit_rqs) + hctx->queue->mq_ops->commit_rqs(hctx); } static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) diff --git a/block/blk-mq.h b/block/blk-mq.h index 9ae8e9f8f8b1..7291e5379358 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -69,7 +69,7 @@ void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, struct list_head *list); /* Used by blk_insert_cloned_request() to issue request directly */ -blk_status_t blk_mq_request_issue_directly(struct request *rq); +blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last); void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, struct list_head *list); -- 2.17.1
