From patchwork Mon Oct 9 11:24:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 9992663 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9BAA360244 for ; Mon, 9 Oct 2017 11:25:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8E69C28797 for ; Mon, 9 Oct 2017 11:25:42 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 834EE287A3; Mon, 9 Oct 2017 11:25:42 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 38E5328797 for ; Mon, 9 Oct 2017 11:25:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754114AbdJILYp (ORCPT ); Mon, 9 Oct 2017 07:24:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49002 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754107AbdJILYl (ORCPT ); Mon, 9 Oct 2017 07:24:41 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 70AB54E4D4; Mon, 9 Oct 2017 11:24:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 70AB54E4D4 Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=ming.lei@redhat.com Received: from localhost (ovpn-12-144.pek2.redhat.com [10.72.12.144]) by smtp.corp.redhat.com (Postfix) with ESMTP id B564961547; Mon, 9 Oct 2017 11:24:40 +0000 (UTC) From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org, Christoph Hellwig , Mike Snitzer , dm-devel@redhat.com Cc: Bart Van Assche , Laurence Oberman , Paolo Valente , Oleksandr Natalenko , Tom Nguyen , linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, Omar Sandoval , Ming Lei Subject: [PATCH V6 2/5] blk-mq-sched: move actual dispatching into one helper Date: Mon, 9 Oct 2017 19:24:21 +0800 Message-Id: <20171009112424.30524-3-ming.lei@redhat.com> In-Reply-To: <20171009112424.30524-1-ming.lei@redhat.com> References: <20171009112424.30524-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Mon, 09 Oct 2017 11:24:41 +0000 (UTC) Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP So that it becomes easy to support to dispatch from sw queue in the following patch. No functional change. Reviewed-by: Bart Van Assche Reviewed-by: Omar Sandoval Suggested-by: Christoph Hellwig # for simplifying dispatch logic Signed-off-by: Ming Lei --- block/blk-mq-sched.c | 43 ++++++++++++++++++++++++------------------- 1 file changed, 24 insertions(+), 19 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index eca011fdfa0e..be29ba849408 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -89,12 +89,26 @@ static bool blk_mq_sched_restart_hctx(struct blk_mq_hw_ctx *hctx) return false; } +static void blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) +{ + struct request_queue *q = hctx->queue; + struct elevator_queue *e = q->elevator; + LIST_HEAD(rq_list); + + do { + struct request *rq = e->type->ops.mq.dispatch_request(hctx); + + if (!rq) + break; + list_add(&rq->queuelist, &rq_list); + } while (blk_mq_dispatch_rq_list(q, &rq_list)); +} + void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; struct elevator_queue *e = q->elevator; const bool has_sched_dispatch = e && e->type->ops.mq.dispatch_request; - bool do_sched_dispatch = true; LIST_HEAD(rq_list); /* RCU or SRCU read lock is needed before checking quiesced flag */ @@ -122,30 +136,21 @@ void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) * scheduler, we can no longer merge or sort them. So it's best to * leave them there for as long as we can. Mark the hw queue as * needing a restart in that case. + * + * We want to dispatch from the scheduler if there was nothing + * on the dispatch list or we were able to dispatch from the + * dispatch list. */ if (!list_empty(&rq_list)) { blk_mq_sched_mark_restart_hctx(hctx); - do_sched_dispatch = blk_mq_dispatch_rq_list(q, &rq_list); - } else if (!has_sched_dispatch) { + if (blk_mq_dispatch_rq_list(q, &rq_list) && has_sched_dispatch) + blk_mq_do_dispatch_sched(hctx); + } else if (has_sched_dispatch) { + blk_mq_do_dispatch_sched(hctx); + } else { blk_mq_flush_busy_ctxs(hctx, &rq_list); blk_mq_dispatch_rq_list(q, &rq_list); } - - /* - * We want to dispatch from the scheduler if there was nothing - * on the dispatch list or we were able to dispatch from the - * dispatch list. - */ - if (do_sched_dispatch && has_sched_dispatch) { - do { - struct request *rq; - - rq = e->type->ops.mq.dispatch_request(hctx); - if (!rq) - break; - list_add(&rq->queuelist, &rq_list); - } while (blk_mq_dispatch_rq_list(q, &rq_list)); - } } bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,