From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31F50C433E2 for ; Mon, 25 May 2020 09:38:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0FB9E2073B for ; Mon, 25 May 2020 09:38:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QqfyZrmi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389365AbgEYJiq (ORCPT ); Mon, 25 May 2020 05:38:46 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27050 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2389607AbgEYJiq (ORCPT ); Mon, 25 May 2020 05:38:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590399525; 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=t8aU7NqLVWXDrPNslboZq3TKIU4tGVfOYFyWz3OsDiM=; b=QqfyZrmilHd9aYjXaas7Y8LJamWMQUktLWrnR3IW1ZLbo0f33LEXa4U8j3ljvGnmVK+SvB G1YS8qI8jaL+Om+TjdnDuDVsBoXMztLW4QKAua01UOdzBxl0om5pE3nA9s1dFPr4gGIPAs gRMIb5Km5dcyH4kEC3KZ/I/xiuBY5qk= 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-159-dhIbG7MONXuqpuf3tEx1XA-1; Mon, 25 May 2020 05:38:41 -0400 X-MC-Unique: dhIbG7MONXuqpuf3tEx1XA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1B078460; Mon, 25 May 2020 09:38:40 +0000 (UTC) Received: from localhost (ovpn-12-137.pek2.redhat.com [10.72.12.137]) by smtp.corp.redhat.com (Postfix) with ESMTP id BD6BE19D61; Mon, 25 May 2020 09:38:36 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Ming Lei , Sagi Grimberg , Baolin Wang , Christoph Hellwig Subject: [PATCH V2 3/6] blk-mq: move getting driver tag and bugget into one helper Date: Mon, 25 May 2020 17:38:04 +0800 Message-Id: <20200525093807.805155-4-ming.lei@redhat.com> In-Reply-To: <20200525093807.805155-1-ming.lei@redhat.com> References: <20200525093807.805155-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Move code for getting driver tag and bugget into one helper, so blk_mq_dispatch_rq_list gets a bit simpified, and easier to read. Meantime move updating of 'no_tag' and 'no_budget_avaiable' into the branch for handling partial dispatch because that is exactly consumer of the two local variables. Also rename the parameter of 'got_budget' as 'ask_budget'. No functional change. Cc: Sagi Grimberg Cc: Baolin Wang Cc: Christoph Hellwig Reviewed-by: Sagi Grimberg Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei --- block/blk-mq.c | 75 +++++++++++++++++++++++++++++++++----------------- 1 file changed, 49 insertions(+), 26 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index b0049f4d5128..1b257a94b020 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1230,18 +1230,51 @@ static void blk_mq_handle_zone_resource(struct request *rq, __blk_mq_requeue_request(rq); } +enum prep_dispatch { + PREP_DISPATCH_OK, + PREP_DISPATCH_NO_TAG, + PREP_DISPATCH_NO_BUDGET, +}; + +static enum prep_dispatch blk_mq_prep_dispatch_rq(struct request *rq, + bool ask_budget) +{ + struct blk_mq_hw_ctx *hctx = rq->mq_hctx; + + if (ask_budget && !blk_mq_get_dispatch_budget(rq->q)) { + blk_mq_put_driver_tag(rq); + return PREP_DISPATCH_NO_BUDGET; + } + + if (!blk_mq_get_driver_tag(rq)) { + /* + * The initial allocation attempt failed, so we need to + * rerun the hardware queue when a tag is freed. The + * waitqueue takes care of that. If the queue is run + * before we add this entry back on the dispatch list, + * we'll re-run it below. + */ + if (!blk_mq_mark_tag_wait(hctx, rq)) { + /* budget is always obtained before getting tag */ + blk_mq_put_dispatch_budget(rq->q); + return PREP_DISPATCH_NO_TAG; + } + } + + return PREP_DISPATCH_OK; +} + /* * 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) { + enum prep_dispatch prep; struct request_queue *q = hctx->queue; struct request *rq, *nxt; - bool no_tag = false; int errors, queued; blk_status_t ret = BLK_STS_OK; - bool no_budget_avail = false; LIST_HEAD(zone_list); if (list_empty(list)) @@ -1259,31 +1292,9 @@ 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); - if (!got_budget && !blk_mq_get_dispatch_budget(q)) { - blk_mq_put_driver_tag(rq); - no_budget_avail = true; + prep = blk_mq_prep_dispatch_rq(rq, !got_budget); + if (prep != PREP_DISPATCH_OK) break; - } - - if (!blk_mq_get_driver_tag(rq)) { - /* - * The initial allocation attempt failed, so we need to - * rerun the hardware queue when a tag is freed. The - * waitqueue takes care of that. If the queue is run - * before we add this entry back on the dispatch list, - * we'll re-run it below. - */ - if (!blk_mq_mark_tag_wait(hctx, rq)) { - blk_mq_put_dispatch_budget(q); - /* - * For non-shared tags, the RESTART check - * will suffice. - */ - if (hctx->flags & BLK_MQ_F_TAG_SHARED) - no_tag = true; - break; - } - } list_del_init(&rq->queuelist); @@ -1336,6 +1347,18 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, */ if (!list_empty(list)) { bool needs_restart; + bool no_tag = false; + bool no_budget_avail = false; + + /* + * For non-shared tags, the RESTART check + * will suffice. + */ + if (prep == PREP_DISPATCH_NO_TAG && + (hctx->flags & BLK_MQ_F_TAG_SHARED)) + no_tag = true; + if (prep == PREP_DISPATCH_NO_BUDGET) + no_budget_avail = true; /* * If we didn't flush the entire list, we could have told -- 2.25.2