From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=fromorbit-com.20230601.gappssmtp.com header.i=@fromorbit-com.20230601.gappssmtp.com header.b="K1nmfMaY" Received: from mail-pl1-x632.google.com (mail-pl1-x632.google.com [IPv6:2607:f8b0:4864:20::632]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57D4712A for ; Wed, 22 Nov 2023 14:26:48 -0800 (PST) Received: by mail-pl1-x632.google.com with SMTP id d9443c01a7336-1ce3084c2d1so2093525ad.3 for ; Wed, 22 Nov 2023 14:26:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fromorbit-com.20230601.gappssmtp.com; s=20230601; t=1700692008; x=1701296808; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=EPKxp1wHu2X0l3z9q2thW4znkTvrAEpmGlqWbMXtNbI=; b=K1nmfMaYP9ss6mjH+3DHBwAgdllDAMo0MMMuwkTGvikGXypBIaRObThkDJC69ZnB5O oXaHdq3Ep1QJ9XyIqVvMYS7g7tS6ZJ15jqAQGL3ZfA/XfRU8VGgbd7h9+J5ZGM3TKKpj o+n7qmqabs/Yte/TRFSpHnLsOO2fTvpTcimM1/IkQq8RtDyhxRRetlHz92DncQgVFOEV 8Flpmcx5FiQy6YEG/8TnRbg2z1S/0QoBdOfBPKM/jtHXbqa24H516H1O7T17dFenhRsO 2hSLbcKuQk7mNYiTJx99ERf9q9nz+gQR1W4Kw+GW2czYW+1v+Y3D/J2moXhGkZdp2Iwr QzUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700692008; x=1701296808; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=EPKxp1wHu2X0l3z9q2thW4znkTvrAEpmGlqWbMXtNbI=; b=elltK48S1v6Ho86e+x19ZZQf7/jSjNBtfqKZkEPW3lSqjptuVJMMFEPAPiw11Oau2+ 8JB3yciOJx+5UOEepv1D1/s6gWuqZsJjTu4han5TGWVw0TWMjKUUyBDO0cxtrfQCqKVn q7HuMqQDQgddSN4xWUp8tG3uRd0f8OvwRr6fxxeNrQNMNtX6aGrk0nRtDEjhHCqg97/e V5yQXfvUPsbQpdRgXWXJ1431LWxBiPO4p11Om0dMS6iXplUa6SHSUmgtEmwdwsM3GPUB pwASmUX5doUuNmyGXl1aKXvBqIbFLH/fXUzHiZIRKSK77mzeqAm2OQYZN3liQ/RLIgNs yW3A== X-Gm-Message-State: AOJu0Yx2ScZMZAFz0EKk+epPaIMVom3HcBIPQkrpRQwycJzSLJjt6NDj Mys7cvc9SgScf0jXNkufmOqz8wdUnWFXCZT4VVc= X-Google-Smtp-Source: AGHT+IGJj4E4nSH8dpmDgva7z7MZT3uUEdfdUQu+dt8cC71QACDytNujG1h6BtgWAoV+3cpm75iHUw== X-Received: by 2002:a17:902:ea8b:b0:1cf:8546:3376 with SMTP id x11-20020a170902ea8b00b001cf85463376mr1224073plb.5.1700692007804; Wed, 22 Nov 2023 14:26:47 -0800 (PST) Received: from dread.disaster.area (pa49-180-125-5.pa.nsw.optusnet.com.au. [49.180.125.5]) by smtp.gmail.com with ESMTPSA id ja21-20020a170902efd500b001cc47c1c29csm189754plb.84.2023.11.22.14.26.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Nov 2023 14:26:47 -0800 (PST) Received: from dave by dread.disaster.area with local (Exim 4.96) (envelope-from ) id 1r5vgD-00GBwK-01; Thu, 23 Nov 2023 09:26:45 +1100 Date: Thu, 23 Nov 2023 09:26:44 +1100 From: Dave Chinner To: Christoph Hellwig Cc: Jan Kara , "Ritesh Harjani (IBM)" , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [RFC 2/3] ext2: Convert ext2 regular file buffered I/O to use iomap Message-ID: References: <20231122122946.wg3jqvem6fkg3tgw@quack3> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Nov 22, 2023 at 05:11:18AM -0800, Christoph Hellwig wrote: > On Wed, Nov 22, 2023 at 01:29:46PM +0100, Jan Kara wrote: > > writeback bit set. XFS plays the revalidation sequence counter games > > because of this so we'd have to do something similar for ext2. Not that I'd > > care as much about ext2 writeback performance but it should not be that > > hard and we'll definitely need some similar solution for ext4 anyway. Can > > you give that a try (as a followup "performance improvement" patch). > > Darrick has mentioned that he is looking into lifting more of the > validation sequence counter validation into iomap. I think that was me, as part of aligning the writeback path with the ->iomap_valid() checks in the write path after we lock the folio we instantiated for the write. It's basically the same thing - once we have a locked folio, we have to check that the cached iomap is still valid before we use it for anything. I need to find the time to get back to that, though. -Dave. -- Dave Chinner david@fromorbit.com