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=-17.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 EE1A1C432BE for ; Fri, 27 Aug 2021 02:22:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA82F60F92 for ; Fri, 27 Aug 2021 02:22:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242967AbhH0CXi (ORCPT ); Thu, 26 Aug 2021 22:23:38 -0400 Received: from mail-pf1-f180.google.com ([209.85.210.180]:38841 "EHLO mail-pf1-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234303AbhH0CX3 (ORCPT ); Thu, 26 Aug 2021 22:23:29 -0400 Received: by mail-pf1-f180.google.com with SMTP id a21so4398185pfh.5 for ; Thu, 26 Aug 2021 19:22:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=4U4flyACKgZlu8CovgHCWn5oQfGf8JWy5/o78NqD2x4=; b=ggiFtPB4vZOeWDvwO151dQY+5cz6rFJRXRiEDlyFTP2gqoI1ceifU5YhGo1CwUgoyY WmH0TRjm26cQJPSIT+Kr6HvXyoLulsi3uNZy4PpziFi9Xwyi4GMXAgtzm/a9Pm5BB/L3 zWHcwg54UCE52JzGF4APAbibvPAbZdHS4uVbIkOQRYaj5cQPh/DgpzlKM2dhx3k5Epir xq3Jut3LkGQ/VsQ+AKTsjdpLUJGf7XHe0oaSxx8pMy+cKBpWmNoTJKyRjn9ax1SUBjM5 GgMDFleKNdKyU/RzFw5tNUhzQsJIVPZc/CsrvKC/N6/VUZk0vgUut21lsCsYxliWP5xY hmkQ== X-Gm-Message-State: AOAM533NXuE7jhvkI+1hb4SHvMiP3nuhgOvhEzfiWFih1RBkVcrQC1nu tvQGMJqzUHCZQrMkL7W2wwI= X-Google-Smtp-Source: ABdhPJzo9okpRck3dkxDResb3ytqA67UOqAebZmFicN0nIqKa4jZDh8VUKDAdyfosvx51md+s/JF0A== X-Received: by 2002:a63:4614:: with SMTP id t20mr5928353pga.372.1630030961142; Thu, 26 Aug 2021 19:22:41 -0700 (PDT) Received: from ?IPv6:2601:647:4000:d7:4949:2f:2d87:ed91? ([2601:647:4000:d7:4949:2f:2d87:ed91]) by smtp.gmail.com with ESMTPSA id q26sm4270461pff.174.2021.08.26.19.22.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 26 Aug 2021 19:22:40 -0700 (PDT) Subject: Re: [PATCH] mq-deadline: Fix request accounting To: Niklas Cassel Cc: Jens Axboe , "linux-block@vger.kernel.org" , Christoph Hellwig , Jaegeuk Kim , Damien Le Moal , Hannes Reinecke References: <20210824170520.1659173-1-bvanassche@acm.org> From: Bart Van Assche Message-ID: <18594aff-4a94-8a48-334c-f21ae32120c6@acm.org> Date: Thu, 26 Aug 2021 19:22:38 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 8/24/21 2:35 PM, Niklas Cassel wrote: > Reviewed-by: Niklas Cassel > Tested-by: Niklas Cassel Hi Niklas, Thank you for the help, that's really appreciated. Earlier today I discovered that this patch does not handle requeuing correctly so I have started testing the patch below. --- block/mq-deadline.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/block/mq-deadline.c b/block/mq-deadline.c index dbd74bae9f11..c4c3c2e3f446 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -712,7 +712,10 @@ static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, blk_req_zone_write_unlock(rq); prio = ioprio_class_to_prio[ioprio_class]; - dd_count(dd, inserted, prio); + if (!rq->elv.priv[0]) { + dd_count(dd, inserted, prio); + rq->elv.priv[0] = (void *)(uintptr_t)1; + } if (blk_mq_sched_try_insert_merge(q, rq, &free)) { blk_mq_free_requests(&free); @@ -761,12 +764,10 @@ static void dd_insert_requests(struct blk_mq_hw_ctx *hctx, spin_unlock(&dd->lock); } -/* - * Nothing to do here. This is defined only to ensure that .finish_request - * method is called upon request completion. - */ +/* Callback from inside blk_mq_rq_ctx_init(). */ static void dd_prepare_request(struct request *rq) { + rq->elv.priv[0] = NULL; } /* @@ -793,6 +794,14 @@ static void dd_finish_request(struct request *rq) const enum dd_prio prio = ioprio_class_to_prio[ioprio_class]; struct dd_per_prio *per_prio = &dd->per_prio[prio]; + /* + * The block layer core may call dd_finish_request() without having + * called dd_insert_requests(). Skip requests that bypassed I/O + * scheduling. See also blk_mq_request_bypass_insert(). + */ + if (!rq->elv.priv[0]) + return; + dd_count(dd, completed, prio); if (blk_queue_is_zoned(q)) {