From patchwork Mon Nov 30 02:46:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 11939581 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 EB89AC64E90 for ; Mon, 30 Nov 2020 02:47:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C0A3C20809 for ; Mon, 30 Nov 2020 02:47:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726995AbgK3CrX (ORCPT ); Sun, 29 Nov 2020 21:47:23 -0500 Received: from mail-pj1-f68.google.com ([209.85.216.68]:38656 "EHLO mail-pj1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726691AbgK3CrW (ORCPT ); Sun, 29 Nov 2020 21:47:22 -0500 Received: by mail-pj1-f68.google.com with SMTP id j13so433189pjz.3; Sun, 29 Nov 2020 18:47:07 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=4JgpHAM7ijqDR/daqOEIIKcPlm8O8muBHkiT8mO3EUY=; b=OU5hFKJ7Pj125/WpCiIgABuKzjbZT7By+/pnOy8fcyfCBDBJGfr+UmppqJhn8oslp1 rvlZjQFJ7DyLz1pKjysRBA/eASVE0CYuIQr/G0Ku+1xMQx07w27IBtgmtp65nL6ng+Fy jO/oo7dUBZ9wL5rVspSncizF8FKd/tpoSknAFDyEKsKiOughgYolzSBZVQmLQd7gJPtd 8B+ANvFToIhYVY0tVrOY8LwPorig/bUu77eD8iG7VBf99taGU3Ns3IIYJlJ6K9ABfnqG /rHCAMVRgRgUE4srDWJtdpeX4XgY/nI9Gih+wyvUW/PMHUyJkAnwLD6zr8zd3t9j612+ c4Wg== X-Gm-Message-State: AOAM533fmR1+szOtJG4es6TCVM8DjY+e/CANNB7UeHEpU8jOhsQCN7Er gu2Tarp4ZFU7DS4V73Ygg48= X-Google-Smtp-Source: ABdhPJySzFwaS9kN5Nehx4yAWHDsKt0CycJXycGTqD+OB5huQZiDmvnMpZPa38YaDmL3k1FJ6d0fow== X-Received: by 2002:a17:90a:aa14:: with SMTP id k20mr23553945pjq.131.1606704401812; Sun, 29 Nov 2020 18:46:41 -0800 (PST) Received: from asus.hsd1.ca.comcast.net (c-73-241-217-19.hsd1.ca.comcast.net. [73.241.217.19]) by smtp.gmail.com with ESMTPSA id n127sm14734659pfd.143.2020.11.29.18.46.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 29 Nov 2020 18:46:40 -0800 (PST) From: Bart Van Assche To: "Martin K . Petersen" Cc: "James E . J . Bottomley" , Jens Axboe , Christoph Hellwig , Ming Lei , linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, Bart Van Assche , Alan Stern , Can Guo , Stanley Chu , "Rafael J . Wysocki" , Martin Kepplinger Subject: [PATCH v4 9/9] block: Do not accept any requests while suspended Date: Sun, 29 Nov 2020 18:46:15 -0800 Message-Id: <20201130024615.29171-10-bvanassche@acm.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201130024615.29171-1-bvanassche@acm.org> References: <20201130024615.29171-1-bvanassche@acm.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Alan Stern blk_queue_enter() accepts BLK_MQ_REQ_PM requests independent of the runtime power management state. Now that SCSI domain validation no longer depends on this behavior, modify the behavior of blk_queue_enter() as follows: - Do not accept any requests while suspended. - Only process power management requests while suspending or resuming. Submitting BLK_MQ_REQ_PM requests to a device that is runtime suspended causes runtime-suspended devices not to resume as they should. The request which should cause a runtime resume instead gets issued directly, without resuming the device first. Of course the device can't handle it properly, the I/O fails, and the device remains suspended. The problem is fixed by checking that the queue's runtime-PM status isn't RPM_SUSPENDED before allowing a request to be issued, and queuing a runtime-resume request if it is. In particular, the inline blk_pm_request_resume() routine is renamed blk_pm_resume_queue() and the code is unified by merging the surrounding checks into the routine. If the queue isn't set up for runtime PM, or there currently is no restriction on allowed requests, the request is allowed. Likewise if the BLK_MQ_REQ_PM flag is set and the status isn't RPM_SUSPENDED. Otherwise a runtime resume is queued and the request is blocked until conditions are more suitable. Reviewed-by: Christoph Hellwig Reviewed-by: Can Guo Reviewed-by: Stanley Chu Cc: Ming Lei Cc: Rafael J. Wysocki Reported-and-tested-by: Martin Kepplinger Signed-off-by: Alan Stern Signed-off-by: Bart Van Assche [ bvanassche: modified commit message and removed Cc: stable because without the previous patches from this series this patch would break parallel SCSI domain validation ] Reviewed-by: Hannes Reinecke --- block/blk-core.c | 6 +++--- block/blk-pm.h | 14 +++++++++----- 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index a00bce9f46d8..230880cbf8c8 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -440,7 +440,8 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) * responsible for ensuring that that counter is * globally visible before the queue is unfrozen. */ - if (pm || !blk_queue_pm_only(q)) { + if ((pm && q->rpm_status != RPM_SUSPENDED) || + !blk_queue_pm_only(q)) { success = true; } else { percpu_ref_put(&q->q_usage_counter); @@ -465,8 +466,7 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) wait_event(q->mq_freeze_wq, (!q->mq_freeze_depth && - (pm || (blk_pm_request_resume(q), - !blk_queue_pm_only(q)))) || + blk_pm_resume_queue(pm, q)) || blk_queue_dying(q)); if (blk_queue_dying(q)) return -ENODEV; diff --git a/block/blk-pm.h b/block/blk-pm.h index ea5507d23e75..a2283cc9f716 100644 --- a/block/blk-pm.h +++ b/block/blk-pm.h @@ -6,11 +6,14 @@ #include #ifdef CONFIG_PM -static inline void blk_pm_request_resume(struct request_queue *q) +static inline int blk_pm_resume_queue(const bool pm, struct request_queue *q) { - if (q->dev && (q->rpm_status == RPM_SUSPENDED || - q->rpm_status == RPM_SUSPENDING)) - pm_request_resume(q->dev); + if (!q->dev || !blk_queue_pm_only(q)) + return 1; /* Nothing to do */ + if (pm && q->rpm_status != RPM_SUSPENDED) + return 1; /* Request allowed */ + pm_request_resume(q->dev); + return 0; } static inline void blk_pm_mark_last_busy(struct request *rq) @@ -44,8 +47,9 @@ static inline void blk_pm_put_request(struct request *rq) --rq->q->nr_pending; } #else -static inline void blk_pm_request_resume(struct request_queue *q) +static inline int blk_pm_resume_queue(const bool pm, struct request_queue *q) { + return 1; } static inline void blk_pm_mark_last_busy(struct request *rq)