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=-9.9 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,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 06754C10F27 for ; Tue, 10 Mar 2020 13:07:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0FE420409 for ; Tue, 10 Mar 2020 13:07:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=android.com header.i=@android.com header.b="MFD38q7B" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730691AbgCJNHO (ORCPT ); Tue, 10 Mar 2020 09:07:14 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:50289 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730923AbgCJNHL (ORCPT ); Tue, 10 Mar 2020 09:07:11 -0400 Received: by mail-wm1-f66.google.com with SMTP id a5so1334746wmb.0 for ; Tue, 10 Mar 2020 06:07:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=android.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=PP63n4exnMNKX7lpvmvyJwMQWnXIxOlpOmy5QQY9xLA=; b=MFD38q7BzBjfElXqAV7xBgBy4BXd4rBDKr7W+kAopPCUZCNA/zrSAWTJTKbG+oxOPr AmfDSgyk63mq6fscWU8aPQOChW8ehrZdp1sE5NpXlcEV4hUUgdkkGaG8I2hP3td7kksZ zie2znp15Ow4/+KpsIM28rxV5SVJyLX9y4cH2W2iIMBZpg7SsmWGQdU085OXLbZwyws4 eUCwyhhgiT+fpl/lnKbL0axo6NoVsJgrexFSl1X/1mmSXIG+72e8bOG63QW/a+/RuntM hveu9qnbXmI6vIJYuZJSpplVYSeQKraoaKTtH2s2pEEFgQd66L8m2f2iOa4PkmZNzI5N 8kHA== 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:mime-version :content-transfer-encoding; bh=PP63n4exnMNKX7lpvmvyJwMQWnXIxOlpOmy5QQY9xLA=; b=gi1stOWMGrWhYpZUNJaoVdOAGsrz/8XuMsRoEXKxLXk904pTcIrFO9LUrBAHmiN8qZ pnuxv1HGYy8SqZf+A/RVShNta1Q+Xt+AZkrGjDHnsvcWQYgyzZKxPG/4hcMbf/1cRt1V MENjTSKDXRpgesbWGYBl3W7s0h3fgqO7/E5dTEqTIxXqxxZ1AeXz+bkYNqLVPi8wZolO Z2eaHp34XDT09oS7f0n60Q+YB0dyUeXwrGQq5w4Dk0ZplzRPt4Y22TGHQKxSpg6RoUJs KhS2KyZaymZ7RYKgn2t4KUSq5ZHzqFeABzA8iQY2E0zGPiOGrqVFBy5DDJ5xEVOhxKT1 fvSg== X-Gm-Message-State: ANhLgQ2/AGZ1LCcSTlfnp+zpn65ZIBl2u/C9inKTxcddSZHsQwqNbH1O M+QGR7zuWj5MH/Z0PRKRuGwUkA== X-Google-Smtp-Source: ADFU+vtEsPNZPcMrSWBibyD6jxev3SWQJHDu3DoFC+EAYrSBKkEFpF1BuZh38BFU06MmgQFunOgrFQ== X-Received: by 2002:a1c:4642:: with SMTP id t63mr2084570wma.164.1583845628929; Tue, 10 Mar 2020 06:07:08 -0700 (PDT) Received: from maco2.ams.corp.google.com (a83-162-234-235.adsl.xs4all.nl. [83.162.234.235]) by smtp.gmail.com with ESMTPSA id w22sm4129323wmk.34.2020.03.10.06.07.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Mar 2020 06:07:07 -0700 (PDT) From: Martijn Coenen To: axboe@kernel.dk, hch@lst.de Cc: bvanassche@acm.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@android.com, Martijn Coenen Subject: [PATCH] loop: Only freeze block queue when needed. Date: Tue, 10 Mar 2020 14:06:54 +0100 Message-Id: <20200310130654.92205-1-maco@android.com> X-Mailer: git-send-email 2.25.1.481.gfbce0eb801-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __loop_update_dio() can be called as a part of loop_set_fd(), when the block queue is not yet up and running; avoid freezing the block queue in that case, since that is an expensive operation. Signed-off-by: Martijn Coenen --- drivers/block/loop.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 739b372a5112..c1c844ad6b1a 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -214,7 +214,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio) * LO_FLAGS_READ_ONLY, both are set from kernel, and losetup * will get updated by ioctl(LOOP_GET_STATUS) */ - blk_mq_freeze_queue(lo->lo_queue); + if (lo->lo_state == Lo_bound) + blk_mq_freeze_queue(lo->lo_queue); lo->use_dio = use_dio; if (use_dio) { blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, lo->lo_queue); @@ -223,7 +224,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio) blk_queue_flag_set(QUEUE_FLAG_NOMERGES, lo->lo_queue); lo->lo_flags &= ~LO_FLAGS_DIRECT_IO; } - blk_mq_unfreeze_queue(lo->lo_queue); + if (lo->lo_state == Lo_bound) + blk_mq_unfreeze_queue(lo->lo_queue); } static int -- 2.25.1.481.gfbce0eb801-goog