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[2620:137:e000::1:20]) by mx.google.com with ESMTP id n7-20020a6543c7000000b0055b82bb0bbdsi2569625pgp.879.2023.08.10.20.22.42; Thu, 10 Aug 2023 20:22:54 -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=@gmail.com header.s=20221208 header.b=f1Rx5ylL; 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=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232218AbjHKCfx (ORCPT + 99 others); Thu, 10 Aug 2023 22:35:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229929AbjHKCfw (ORCPT ); Thu, 10 Aug 2023 22:35:52 -0400 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F3AF171D; Thu, 10 Aug 2023 19:35:52 -0700 (PDT) Received: by mail-pl1-x643.google.com with SMTP id d9443c01a7336-1bc73a2b0easo12200245ad.0; Thu, 10 Aug 2023 19:35:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1691721352; x=1692326152; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=udzCkL4eC0y3DNVQdpkulppZYCE1gWkbBMtzmbo6Y/g=; b=f1Rx5ylLWpDeFvr5Owo0LL90bdr1UNyB2XZeMTDd7ep/0cVWe1PIi0r6TPqpEu6dF+ 26rfrEtGWBeMq/A8TMtRXUQ/87Y5NyPN1xoT3+O2ScTo60NggS2HdnkeUv2pY3eyRNha c3dXsXJpBrcWrxHDbxqDI5xJMGPsy928ruQjKU3OPLmUTM3F2VEU1qlhIcxjuDS7pSSA Z+IDRo0G00O68EJGLyV2rRi5Ij6v0vDlOgqf/Y9mYD19jjDAj9qZTL7D9sBfMW51HvxP 3e/EbLJgbX8aW3I/5vp6/2aXnF8FGosXaxLe6MVh9f8pqUxi7JYprjFmiO0qBFxIo1R4 J4ng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691721352; x=1692326152; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=udzCkL4eC0y3DNVQdpkulppZYCE1gWkbBMtzmbo6Y/g=; b=iD6yw3taITb1tFXk/L2ML4BP7MkuXT8Q4787inGJV53LjLWsTqWrBLX/BLqwrBzcwK WdcZGDqtYmNz2Sk+Lx2AzP19NzjehAMMAChnvQdcAyMpa9ey9Y0hwL/yAa32vDR+h35s fwfNI7BFkypomrq6gCDYe0lVzm/iJ5V2Lb77Ky1SECAs655ZHo9vZ67KAzBK2Vdv2QxD PTbFZDxqzK+UncBU5dFDhA+QDF4/8yyUVg5Y/yXS+2Vq0qDmjQcYUnAGtzXM9K9taN7v Yl6stAJ36UxVNsDfEQvPGN8SUJ1+rRFLnSFDq+/XXC2engnM49OyeYpL1mPORz0sZ9+Z W6Mw== X-Gm-Message-State: AOJu0YwtuhNZYdVDMVX0N1eprRC8PvbnYhaVVYI5n0jVqz+C9+V+1AhT xgmqcUZaRmgG6U37dNgMM9s= X-Received: by 2002:a17:902:c409:b0:1bd:b8c0:b57e with SMTP id k9-20020a170902c40900b001bdb8c0b57emr246501plk.40.1691721351754; Thu, 10 Aug 2023 19:35:51 -0700 (PDT) Received: from localhost.localdomain ([218.66.91.195]) by smtp.gmail.com with ESMTPSA id b13-20020a170903228d00b001ab2b4105ddsm2503071plh.60.2023.08.10.19.35.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Aug 2023 19:35:51 -0700 (PDT) From: xiaoshoukui To: dsterba@suse.cz Cc: clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, xiaoshoukui@gmail.com, xiaoshoukui@ruijie.com.cn Subject: Re: [PATCH] btrfs: fix return value when race occur between balance and cancel/pause Date: Thu, 10 Aug 2023 22:35:47 -0400 Message-Id: <20230811023547.25423-1-xiaoshoukui@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230810120501.GA2420@suse.cz> References: <20230810120501.GA2420@suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 The first thought to solve the problem was to use locks, but after practice, it turn it out that this would made the original code even more complex. The way of tracking status may just a workaround solution. The better solution may is to refactor balance relevant code. I think interface provided to the user is very important for reliability. Looking forward to a better solution, If needed, I can take some effort for testing and reproducing.