From patchwork Wed Jun 3 09:43:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 11585457 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 48667913 for ; Wed, 3 Jun 2020 09:44:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2FB1920734 for ; Wed, 3 Jun 2020 09:44:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FjbDDMPw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726542AbgFCJoU (ORCPT ); Wed, 3 Jun 2020 05:44:20 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:56309 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725854AbgFCJoU (ORCPT ); Wed, 3 Jun 2020 05:44:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591177458; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7pgznPy8EpYuZ3LtOa2bFAOMOanpr7TYXAaMz04cvJ4=; b=FjbDDMPwXujD5M1MRh4/zt87Llrg7h7Ma0qOd6ThqmMo1jLyf421mUwOS4mAC/+qUNjATf 4Sjz1mRdnFpJIfkAkOuHanbJYSbBj8QI5mNz0zSHyzChA+8JditIMV9x7MbYDtF4N6hM0k Gv4wRqMPKT10LGxiPtnnX8RNvsVrbOk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-23-sy9dKoKaPAeR8cb0yw6nHg-1; Wed, 03 Jun 2020 05:44:17 -0400 X-MC-Unique: sy9dKoKaPAeR8cb0yw6nHg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9DDC6107ACCA; Wed, 3 Jun 2020 09:44:15 +0000 (UTC) Received: from localhost (ovpn-12-230.pek2.redhat.com [10.72.12.230]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1F38078B56; Wed, 3 Jun 2020 09:44:11 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Damien Le Moal , Ming Lei , Sagi Grimberg , Baolin Wang , Christoph Hellwig Subject: [PATCH V5 5/6] blk-mq: pass obtained budget count to blk_mq_dispatch_rq_list Date: Wed, 3 Jun 2020 17:43:36 +0800 Message-Id: <20200603094337.2064181-6-ming.lei@redhat.com> In-Reply-To: <20200603094337.2064181-1-ming.lei@redhat.com> References: <20200603094337.2064181-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Pass obtained budget count to blk_mq_dispatch_rq_list(), and prepare for supporting fully batching submission. With the obtained budget count, it is easier to put extra budgets in case of .queue_rq failure. Meantime remove the old 'got_budget' parameter. Cc: Sagi Grimberg Cc: Baolin Wang Cc: Christoph Hellwig Tested-by: Baolin Wang Signed-off-by: Ming Lei --- block/blk-mq-sched.c | 8 ++++---- block/blk-mq.c | 31 +++++++++++++++++++++++++++---- block/blk-mq.h | 3 ++- 3 files changed, 33 insertions(+), 9 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 632c6f8b63f7..4c72073830f3 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -130,7 +130,7 @@ static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) * in blk_mq_dispatch_rq_list(). */ list_add(&rq->queuelist, &rq_list); - } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, true)); + } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, 1)); return ret; } @@ -198,7 +198,7 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) /* round robin for fair dispatch */ ctx = blk_mq_next_ctx(hctx, rq->mq_ctx); - } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, true)); + } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, 1)); WRITE_ONCE(hctx->dispatch_from, ctx); return ret; @@ -238,7 +238,7 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) */ if (!list_empty(&rq_list)) { blk_mq_sched_mark_restart_hctx(hctx); - if (blk_mq_dispatch_rq_list(hctx, &rq_list, false)) { + if (blk_mq_dispatch_rq_list(hctx, &rq_list, 0)) { if (has_sched_dispatch) ret = blk_mq_do_dispatch_sched(hctx); else @@ -251,7 +251,7 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) ret = blk_mq_do_dispatch_ctx(hctx); } else { blk_mq_flush_busy_ctxs(hctx, &rq_list); - blk_mq_dispatch_rq_list(hctx, &rq_list, false); + blk_mq_dispatch_rq_list(hctx, &rq_list, 0); } return ret; diff --git a/block/blk-mq.c b/block/blk-mq.c index 4085dc59bea6..adb2e81c1aac 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1258,7 +1258,12 @@ static enum prep_dispatch blk_mq_prep_dispatch_rq(struct request *rq, * we'll re-run it below. */ if (!blk_mq_mark_tag_wait(hctx, rq)) { - blk_mq_put_dispatch_budget(rq->q); + /* + * All budgets not got from this function will be put + * together during handling partial dispatch + */ + if (need_budget) + blk_mq_put_dispatch_budget(rq->q); return PREP_DISPATCH_NO_TAG; } } @@ -1266,11 +1271,21 @@ static enum prep_dispatch blk_mq_prep_dispatch_rq(struct request *rq, return PREP_DISPATCH_OK; } +/* release all allocated budgets before calling to blk_mq_dispatch_rq_list */ +static void blk_mq_release_budgets(struct request_queue *q, + unsigned int nr_budgets) +{ + int i; + + for (i = 0; i < nr_budgets; i++) + blk_mq_put_dispatch_budget(q); +} + /* * Returns true if we did some work AND can potentially do more. */ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, - bool got_budget) + unsigned int nr_budgets) { enum prep_dispatch prep; struct request_queue *q = hctx->queue; @@ -1282,7 +1297,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, if (list_empty(list)) return false; - WARN_ON(!list_is_singular(list) && got_budget); + WARN_ON(!list_is_singular(list) && nr_budgets); /* * Now process all the entries, sending them to the driver. @@ -1294,7 +1309,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, rq = list_first_entry(list, struct request, queuelist); WARN_ON_ONCE(hctx != rq->mq_hctx); - prep = blk_mq_prep_dispatch_rq(rq, !got_budget); + prep = blk_mq_prep_dispatch_rq(rq, !nr_budgets); if (prep != PREP_DISPATCH_OK) break; @@ -1313,6 +1328,12 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, bd.last = !blk_mq_get_driver_tag(nxt); } + /* + * once the request is queued to lld, no need to cover the + * budget any more + */ + if (nr_budgets) + nr_budgets--; ret = q->mq_ops->queue_rq(hctx, &bd); if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) { blk_mq_handle_dev_resource(rq, list); @@ -1354,6 +1375,8 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, (hctx->flags & BLK_MQ_F_TAG_SHARED); bool no_budget_avail = prep == PREP_DISPATCH_NO_BUDGET; + blk_mq_release_budgets(q, nr_budgets); + /* * If we didn't flush the entire list, we could have told * the driver there was more coming, but that turned out to diff --git a/block/blk-mq.h b/block/blk-mq.h index d2d737b16e0e..f3a93acfad03 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -40,7 +40,8 @@ struct blk_mq_ctx { void blk_mq_exit_queue(struct request_queue *q); int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr); void blk_mq_wake_waiters(struct request_queue *q); -bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *, bool); +bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *, + unsigned int); void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, bool kick_requeue_list); void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);