From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756563AbbDUXHX (ORCPT ); Tue, 21 Apr 2015 19:07:23 -0400 Received: from cantor2.suse.de ([195.135.220.15]:54465 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753428AbbDUXHU (ORCPT ); Tue, 21 Apr 2015 19:07:20 -0400 Date: Wed, 22 Apr 2015 09:06:53 +1000 From: NeilBrown To: Christoph Hellwig Cc: David Howells , Chris Mason , Al Viro , Josef Bacik , David Sterba , linux-cachefs@vger.kernel.org, Dave Chinner , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org Subject: Re: [PATCH 2/3] fscache/cachefiles: optionally use SEEK_DATA instead of ->bmap. Message-ID: <20150422090653.35ad074c@notabene.brown> In-Reply-To: <20150420094539.GA12622@infradead.org> References: <20150420052558.26554.97143.stgit@notabene.brown> <20150420052752.26554.52672.stgit@notabene.brown> <20150420060818.GA32675@infradead.org> <20150420162700.3e69c7db@notabene.brown> <20150420094539.GA12622@infradead.org> X-Mailer: Claws Mail 3.10.1-162-g4d0ed6 (GTK+ 2.24.25; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/34Rpsa0blcVekf+q/NTN0l1"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/34Rpsa0blcVekf+q/NTN0l1 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 20 Apr 2015 02:45:39 -0700 Christoph Hellwig wrote: > On Mon, Apr 20, 2015 at 04:27:00PM +1000, NeilBrown wrote: > > A worthwhile goal, but I certainly wouldn't consider pursuing it until = what I > > have submitted so far as been accepted - let's not reject "good" while > > waiting for "perfect". >=20 > It's still broken. You add conditional flag for the almost right > (almost because the flag in the filesystem type needs to go) Why does it have to go? I suspect you have a reason, but I can't read your mind. > while > leaving the broken option th default.=20 You say it is broken, and yet people are using it and are having a degree of success. Surely the appropriate process is: - introduce a "better" option - examine each relevant filesystem and transition over to use the new opti= on. - remove the "not so good" option. I'm still at step 1. > So what you propose here is not > good, it's at best just as bad as the old version because you don't > remove broken code but add a lot more clutter at the same time. What I propose is measurably better because it works with BTRFS now, and there seems to be a reasonable path towards making to generally better if someone cares enough to examine each filesystem. So I still claim you are pushing back against "good" because you want "perfect". NeilBrown --Sig_/34Rpsa0blcVekf+q/NTN0l1 Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUBVTbYEDnsnt1WYoG5AQIbuQ/+J75ySYqP83GzlIjavqUtdAuAUxF6f1k/ 8tTK5UcaiiCIl4B3i1zt2yavV7g1iP186n9SizND29jESVVMVCYGVtlaV2N6xKWM U3A86AljdUuY4zMIJsoXUdToaaIUBQuUKR5nh1GdL6TqWOwgjwvpaz/dDnDo934K kvIhXx2HFHqAvyNmSJZOe+wmJF9N64C6H9//dUY2QQrUxdf82HAf8j3u5QObhGXt COOIGSf/fDunj3qwaMcBcwOFaXP6BtpMofsPIsnyQ5FtsMrqoEbDLdh7lVoiv1KW 5/sadxbFaDHC2S4mNKyy+8v3jC3lf/l/Npu0bP608UiXHCPjpXRAOKhzbdSUOnNr dHVmx6+4syQG16R+ysGOaVX/8mSQaT+uXaOYSaPwPjPYhU07RwQTRnOwK46I38SF rND1PNbz/C3mC2WKRq1QLpt4uiK8X8z4bJCZrFdMQSwSITirSkjKexaxSlCOCFTf H0gmjcM80dsXoaaGCo4bf+kC/Ac+JS1Ksoxi4rkQy/dy56Hp/VieHZ0ZtQzgryBf Menj3NnLEn22R2WfHk+9oDZ7psKBY2919ZubsvEeqT3t9F2LEgJOrJEjydF94qMi n2L6xClwf1oHmuxrGOgOpBDrNUzmAhrtXvz+huPEOwf3zH6iba6ekx32XxxRPDY4 p2SwDHYJq7E= =1Y6T -----END PGP SIGNATURE----- --Sig_/34Rpsa0blcVekf+q/NTN0l1--