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Ts'o" To: Konstantin Khlebnikov CC: , Andreas Dilger , , Subject: Re: [PATCH] ext4: add sysfs attr /sys/fs/ext4//journal_task Message-ID: <20190221165258.GE10245@mit.edu> Mail-Followup-To: "Theodore Y. Ts'o" , Konstantin Khlebnikov , linux-fsdevel@vger.kernel.org, Andreas Dilger , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org References: <154927546304.133377.2385004506198637025.stgit@buzz> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <154927546304.133377.2385004506198637025.stgit@buzz> User-Agent: Mutt/1.10.1 (2018-07-13) X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:18.9.28.11;IPV:CAL;SCL:-1;CTRY:US;EFV:NLI;SFV:NSPM;SFS:(10019020)(346002)(136003)(376002)(39860400002)(396003)(2980300002)(189003)(199004)(8676002)(46406003)(11346002)(126002)(106466001)(8936002)(2616005)(97756001)(305945005)(50466002)(476003)(246002)(88552002)(33656002)(356004)(76176011)(26826003)(478600001)(486006)(2906002)(75432002)(23726003)(47776003)(336012)(4744005)(90966002)(106002)(26005)(186003)(4326008)(16586007)(42186006)(316002)(786003)(36756003)(58126008)(36906005)(14444005)(6266002)(6246003)(54906003)(5660300002)(6916009)(229853002)(103686004)(52956003)(86362001)(1076003)(446003)(18370500001)(42866002);DIR:OUT;SFP:1102;SCL:1;SRVR:BYAPR01MB3990;H:outgoing.mit.edu;FPR:;SPF:Pass;LANG:en;PTR:outgoing-auth-1.mit.edu;MX:1;A:1; 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if the file system does not have a journal, reading the /sys/fs/ext4//journal_task will return "" instead of returning a ESRCH error. - Ted