From patchwork Thu Dec 16 16:38:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 12682097 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E903DC4332F for ; Thu, 16 Dec 2021 16:39:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233284AbhLPQjF (ORCPT ); Thu, 16 Dec 2021 11:39:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229480AbhLPQjF (ORCPT ); Thu, 16 Dec 2021 11:39:05 -0500 Received: from mail-il1-x130.google.com (mail-il1-x130.google.com [IPv6:2607:f8b0:4864:20::130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C51B2C061574 for ; Thu, 16 Dec 2021 08:39:04 -0800 (PST) Received: by mail-il1-x130.google.com with SMTP id d14so20172226ila.1 for ; Thu, 16 Dec 2021 08:39:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=/pPKkXtT6Xrl9aqdgr4UGNl+ZJEtLSBkw/CIGk0Ps8Y=; b=OrdIjvCOXY0D0TMhorH3nRbwYFZcB54ze7TN98Pgntko5rub26f5OWcC/o8nw+ATvJ ROzMEapHo1abx6igYSx+SJv5yWUw2fodYo3ajfEfxj9MofnbX3x2lrp3et8IeSYo48CS ti1UsKR7wA0orUTz52eSlAWp7e0C9m0rtZBJHbUNIq6TzSNBvArOFDLElnPV0DsZ6yDj I44eRTDecpJ1D/pLGhoMs6EEa3oNO59aebTWElSx6pYfkf+Oq99xFlTxEy7Q1d/7INDQ kC3Fdr2lz8524jQZtl0KlShO4HoqGMtJMi59DNh8isyZ0fBJuGPEjmoyjPZHnCu7/lvT m5ZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=/pPKkXtT6Xrl9aqdgr4UGNl+ZJEtLSBkw/CIGk0Ps8Y=; b=cSq7Zu53RWQzSEZYn7qTWyfrYSRIdazn7zWoGxQDOxpQLaXs2fYVa/bRORxoVIyQo0 0Io7LoYeinJFVTMlBVH/zu2ZJ6UKwkPkj/NYhZjcZmhlztPhk7wGgytmsD5do/AE8aJG x+W63bFiuI9V/dWH3tsLJLX3ALdCyzIZ9n8TjS7JN6mS56gKhMHrlXOu1/eaa8GuY8ha 9D+x4JbO/+xWU3hIGzTKRukXOg3etbcOBe730LwrsHBrtNsFlGZeZ4tFt9CcY8fwZPs4 wbux7dgZL47nqikky40YjjiFYylSNQrnscHzhbvfEUEoo2LDDJTJ5yLHJBzSBeOOVvXj twGw== X-Gm-Message-State: AOAM532mS1hx0nverMC6fpbCTSWhwMTidLPuWD3C9Z7YvEGvsxwMofLj kxVg7cCN+y5JuqKCg1s/85MxJA== X-Google-Smtp-Source: ABdhPJwQb6QdZqPg4FFtSRHmv+JA7S9z28uquNJFXf+nY1Sz3Gy2ArQ3OY+7RONlUp8vi3Km9w7CEQ== X-Received: by 2002:a05:6e02:15c8:: with SMTP id q8mr10367323ilu.21.1639672744121; Thu, 16 Dec 2021 08:39:04 -0800 (PST) Received: from x1.localdomain ([207.135.234.126]) by smtp.gmail.com with ESMTPSA id t17sm71816ilm.46.2021.12.16.08.39.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Dec 2021 08:39:03 -0800 (PST) From: Jens Axboe To: io-uring@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org Cc: Jens Axboe , Christoph Hellwig Subject: [PATCH 1/4] block: add mq_ops->queue_rqs hook Date: Thu, 16 Dec 2021 09:38:58 -0700 Message-Id: <20211216163901.81845-2-axboe@kernel.dk> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211216163901.81845-1-axboe@kernel.dk> References: <20211216163901.81845-1-axboe@kernel.dk> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org If we have a list of requests in our plug list, send it to the driver in one go, if possible. The driver must set mq_ops->queue_rqs() to support this, if not the usual one-by-one path is used. Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq.c | 26 +++++++++++++++++++++++--- include/linux/blk-mq.h | 8 ++++++++ 2 files changed, 31 insertions(+), 3 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 75154cc788db..51991232824a 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2553,6 +2553,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) { struct blk_mq_hw_ctx *this_hctx; struct blk_mq_ctx *this_ctx; + struct request *rq; unsigned int depth; LIST_HEAD(list); @@ -2561,7 +2562,28 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) plug->rq_count = 0; if (!plug->multiple_queues && !plug->has_elevator && !from_schedule) { - struct request_queue *q = rq_list_peek(&plug->mq_list)->q; + struct request_queue *q; + + rq = rq_list_peek(&plug->mq_list); + q = rq->q; + + /* + * Peek first request and see if we have a ->queue_rqs() hook. + * If we do, we can dispatch the whole plug list in one go. We + * already know at this point that all requests belong to the + * same queue, caller must ensure that's the case. + * + * Since we pass off the full list to the driver at this point, + * we do not increment the active request count for the queue. + * Bypass shared tags for now because of that. + */ + if (q->mq_ops->queue_rqs && + !(rq->mq_hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { + blk_mq_run_dispatch_ops(q, + q->mq_ops->queue_rqs(&plug->mq_list)); + if (rq_list_empty(plug->mq_list)) + return; + } blk_mq_run_dispatch_ops(q, blk_mq_plug_issue_direct(plug, false)); @@ -2573,8 +2595,6 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) this_ctx = NULL; depth = 0; do { - struct request *rq; - rq = rq_list_pop(&plug->mq_list); if (!this_hctx) { diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 772f8f921526..550996cf419c 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -492,6 +492,14 @@ struct blk_mq_ops { */ void (*commit_rqs)(struct blk_mq_hw_ctx *); + /** + * @queue_rqs: Queue a list of new requests. Driver is guaranteed + * that each request belongs to the same queue. If the driver doesn't + * empty the @rqlist completely, then the rest will be queued + * individually by the block layer upon return. + */ + void (*queue_rqs)(struct request **rqlist); + /** * @get_budget: Reserve budget before queue request, once .queue_rq is * run, it is driver's responsibility to release the