From patchwork Thu Apr 13 06:28:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chengming Zhou X-Patchwork-Id: 82824 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp826577vqo; Wed, 12 Apr 2023 23:34:59 -0700 (PDT) X-Google-Smtp-Source: AKy350ZXdlN3i0OnSFs5oGzZ7ZOndeVegtWeERSI0isEn0SE+SPBPySzW9rOTKDyqDg6KqSkQ82e X-Received: by 2002:a17:90a:c78f:b0:23e:f8e2:9ed3 with SMTP id gn15-20020a17090ac78f00b0023ef8e29ed3mr755573pjb.43.1681367698835; Wed, 12 Apr 2023 23:34:58 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681367698; cv=none; d=google.com; s=arc-20160816; b=jJqOgeksFy5A6q3M1VNNtALMnFE7Hq13WGUV+5RnaGH1hkc0npn1JkkUWR20sQCnma G6OHrDoegVT8IVrC95wSLuyJeUvDrD4oBVd2FMAtKOzGZqm/PGGv3U7h8AP2NPB3T116 3nUttviQgvHW8O/ugKgY2gAjdRk/vaJQbmUOUZWxfA36e3X/fwJ1SnsgJwZyhy/LRhay mIKeesErWbm/vnQ/M4c5NQJ3lLYqvIVf4JpwdpneYuJo6cM9CuZlomZzX7e/GE2KqH3G nrfXtPYwZPXwrdIRMkwaUU6Vpv26yoMd8kXELwk78A1NGOAtGn42ziK0dhel65+g4uH8 cJpA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from:dkim-signature; bh=egK6cQcoNaTUC/dkRvlJHjCoro533vXXKI06JsMHHhk=; b=A6bTGvKbYYkbEqKHf5BUmpHDQqAYszWvpYaVordi2MPQA7axwtVdGm2IEfi2w6Kei6 MZvYG/nseBQSvxp6QiKEB9AUlDCFLHoLMLlOUzJgTO+Ruk6Y6FtF0x4wsAyEJYznJy+e waoOex1jkl0wNZ3aH0IIIr19qvvFYHpaLAwJTLZhpLTZ8zVSz84SrCKZ4fsznxNCzf5z OJZJhI32lKM8rVCjkzjNl3M7+ftswFWtTM9jcm+6cchOowCuznzvilJHPPTBcbtYU0Uk m9mPK5qsMEqhGGxFtL9x2aFx2Zo+4ACcLK30C/CUK56rrFV1NQzb37/kYkb8oMyCxTow zfLQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=OLgzKgqo; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id mz3-20020a17090b378300b002402e91b437si1172645pjb.147.2023.04.12.23.34.44; Wed, 12 Apr 2023 23:34:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=OLgzKgqo; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229642AbjDMG2p (ORCPT + 99 others); Thu, 13 Apr 2023 02:28:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229441AbjDMG2o (ORCPT ); Thu, 13 Apr 2023 02:28:44 -0400 X-Greylist: delayed 11079 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 12 Apr 2023 23:28:39 PDT Received: from out-50.mta1.migadu.com (out-50.mta1.migadu.com [IPv6:2001:41d0:203:375::32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A20AD83FE for ; Wed, 12 Apr 2023 23:28:39 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1681367316; 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; bh=egK6cQcoNaTUC/dkRvlJHjCoro533vXXKI06JsMHHhk=; b=OLgzKgqo5RxBuxyyghem3Zr+nBfFIoz4x9MKZJJi9MVi/e3ETG7sXqdslYi9DYw1I1X1nH vIKa37IM3boWd8Vmt0udwAuuErkdq+EvP+gwE3dG//cSdwtDfTWQEFrVepocn8VC0wAGXk OdeaTC1QfLAE/f+X4ExEbHVfkF7qUsc= From: chengming.zhou@linux.dev To: axboe@kernel.dk, tj@kernel.org Cc: josef@toxicpanda.com, osandov@fb.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Chengming Zhou , stable@vger.kernel.org Subject: [PATCH v2 1/2] blk-stat: fix QUEUE_FLAG_STATS clear Date: Thu, 13 Apr 2023 14:28:04 +0800 Message-Id: <20230413062805.2081970-1-chengming.zhou@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762989585845621443?= X-GMAIL-MSGID: =?utf-8?q?1763041816144954550?= From: Chengming Zhou We need to set QUEUE_FLAG_STATS for two cases: 1. blk_stat_enable_accounting() 2. blk_stat_add_callback() So we should clear it only when ((q->stats->accounting == 0) && list_empty(&q->stats->callbacks)). blk_stat_disable_accounting() only check if q->stats->accounting is 0 before clear the flag, this patch fix it. Also add list_empty(&q->stats->callbacks)) check when enable, or the flag is already set. The bug can be reproduced on kernel without BLK_DEV_THROTTLING (since it unconditionally enable accounting, see the next patch). # cat /sys/block/sr0/queue/scheduler none mq-deadline [bfq] # cat /sys/kernel/debug/block/sr0/state SAME_COMP|IO_STAT|INIT_DONE|STATS|REGISTERED|NOWAIT|30 # echo none > /sys/block/sr0/queue/scheduler # cat /sys/kernel/debug/block/sr0/state SAME_COMP|IO_STAT|INIT_DONE|REGISTERED|NOWAIT # cat /sys/block/sr0/queue/wbt_lat_usec 75000 We can see that after changing elevator from "bfq" to "none", "STATS" flag is lost even though WBT callback still need it. Fixes: 68497092bde9 ("block: make queue stat accounting a reference") Cc: # v5.17+ Signed-off-by: Chengming Zhou Acked-by: Tejun Heo --- block/blk-stat.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-stat.c b/block/blk-stat.c index 74a1a8c32d86..bc7e0ed81642 100644 --- a/block/blk-stat.c +++ b/block/blk-stat.c @@ -190,7 +190,7 @@ void blk_stat_disable_accounting(struct request_queue *q) unsigned long flags; spin_lock_irqsave(&q->stats->lock, flags); - if (!--q->stats->accounting) + if (!--q->stats->accounting && list_empty(&q->stats->callbacks)) blk_queue_flag_clear(QUEUE_FLAG_STATS, q); spin_unlock_irqrestore(&q->stats->lock, flags); } @@ -201,7 +201,7 @@ void blk_stat_enable_accounting(struct request_queue *q) unsigned long flags; spin_lock_irqsave(&q->stats->lock, flags); - if (!q->stats->accounting++) + if (!q->stats->accounting++ && list_empty(&q->stats->callbacks)) blk_queue_flag_set(QUEUE_FLAG_STATS, q); spin_unlock_irqrestore(&q->stats->lock, flags); } From patchwork Thu Apr 13 06:28:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chengming Zhou X-Patchwork-Id: 82828 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp837042vqo; Thu, 13 Apr 2023 00:01:15 -0700 (PDT) X-Google-Smtp-Source: AKy350bmzDjBXY5J1qB5vg1zIi0BET6FjsK9QeCGQd51Uxjmuk3ZJ4bexMdQL0i64LSKXOuPxMSp X-Received: by 2002:aa7:cad5:0:b0:506:73bf:c8b with SMTP id l21-20020aa7cad5000000b0050673bf0c8bmr652901edt.29.1681369274972; Thu, 13 Apr 2023 00:01:14 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681369274; cv=none; d=google.com; s=arc-20160816; b=kzQBSOyiPoVZQIaKex1r3n3ek46ctFPeZY0Ww6UXYhiKYy8Y6KFs01DzKYJhebC1M1 knJegN/s4iyX9819AmIA9OATBCP3NE1/xK1bFgsYvo/IQ4dSM4OozJhWSnyKsZVnOHHj rdqTVrXf9ZfW+JYEPkMLD0dww66O9c//i0ZGNGZv0XY5rYtwaI2DRCvatZPmzfNWuUjx 0KcoVKgZTcwT/JDExPd5LcMwlhtX285brCn4lB+1OPpyYJoXEzPh6LEtV8d2RnuhskZo POf0eNoInEGD9tn46jmbPsGCPFkUdSYUVkTHBytG4fWycgBpy380+BHnGfgUwPuc+lDA qLvw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=6uuLZUtgeUwzy7HQkKWbC2Y+wAfW1jsm3UvSSwpC9GQ=; b=sARM5MJQFew3hr14ixZ0JnRXWfzZtscr/hV01ATDN/xo05V8gOZc88YqQMK2qRqOkC 0LLniSzE0wAfdxyCVPofYzKjNYCPl2DrPuWiy3kf98Ewlw0x4d+CGvGmJ3NiEABHMU0A BQ7j4bzDpkUwr5+ngJa4tB0gDoOF+O5iZ5W30QqBiaPWZAyRm8Moog8LEztaRbc7LYZt 0jQWP4Y4w4j0nbmIr6kLwmTHCcNJMNlwb0+Je16a5OnKy0/p4k7lQWzCpqE0ojy5o0QD BXGZLrak1XYjoGjgwVqztnkln/cuBm594jVPw2Sx5/OSYdPXx+i/sVGsZFhM7K5lgHd8 ziqA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=KdB0OD7J; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id u1-20020aa7d981000000b004fe96b95bbbsi1173311eds.570.2023.04.13.00.00.50; Thu, 13 Apr 2023 00:01:14 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=KdB0OD7J; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229724AbjDMG2x (ORCPT + 99 others); Thu, 13 Apr 2023 02:28:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229667AbjDMG2v (ORCPT ); Thu, 13 Apr 2023 02:28:51 -0400 Received: from out-8.mta1.migadu.com (out-8.mta1.migadu.com [95.215.58.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C4C57EF8 for ; Wed, 12 Apr 2023 23:28:42 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1681367321; 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=6uuLZUtgeUwzy7HQkKWbC2Y+wAfW1jsm3UvSSwpC9GQ=; b=KdB0OD7JaB79oRR+5d+zVaBx/OkQHm1RI0hi4MuiY0fVYA0qanpEgKP47Ya07PQz7534/g aGRUTTQBYv29sY1tMk+2zU0xsV6T3eukaU7MRE/bcN8yoQ0O50yRYeqmGlUxm0L9kLz0oN tla8TtElBNB6kkQ7rbtyJB2145QiMiA= From: chengming.zhou@linux.dev To: axboe@kernel.dk, tj@kernel.org Cc: josef@toxicpanda.com, osandov@fb.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Chengming Zhou Subject: [PATCH v2 2/2] blk-throttle: only enable blk-stat when BLK_DEV_THROTTLING_LOW Date: Thu, 13 Apr 2023 14:28:05 +0800 Message-Id: <20230413062805.2081970-2-chengming.zhou@linux.dev> In-Reply-To: <20230413062805.2081970-1-chengming.zhou@linux.dev> References: <20230413062805.2081970-1-chengming.zhou@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1763043469239838046?= X-GMAIL-MSGID: =?utf-8?q?1763043469239838046?= From: Chengming Zhou blk_throtl_register() will unconditionally enable blk-stat for gendisk when register, even when we have no BLK_DEV_THROTTLING_LOW config. Since the kernel always has only BLK_DEV_THROTTLING config and the BLK_DEV_THROTTLING_LOW config is still in EXPERIMENTAL state, we can just skip blk-stat when !BLK_DEV_THROTTLING_LOW. Signed-off-by: Chengming Zhou Acked-by: Tejun Heo --- block/blk-throttle.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 47e9d8be68f3..3c07c9cfa70a 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -2439,11 +2439,12 @@ void blk_throtl_register(struct gendisk *disk) #ifndef CONFIG_BLK_DEV_THROTTLING_LOW /* if no low limit, use previous default */ td->throtl_slice = DFL_THROTL_SLICE_HD; -#endif +#else td->track_bio_latency = !queue_is_mq(q); if (!td->track_bio_latency) blk_stat_enable_accounting(q); +#endif } #ifdef CONFIG_BLK_DEV_THROTTLING_LOW