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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 470B8C54FCC for ; Tue, 21 Apr 2020 21:30:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2BB20206E9 for ; Tue, 21 Apr 2020 21:30:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726373AbgDUVa6 (ORCPT ); Tue, 21 Apr 2020 17:30:58 -0400 Received: from mail105.syd.optusnet.com.au ([211.29.132.249]:42880 "EHLO mail105.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725850AbgDUVa6 (ORCPT ); Tue, 21 Apr 2020 17:30:58 -0400 Received: from dread.disaster.area (pa49-180-0-232.pa.nsw.optusnet.com.au [49.180.0.232]) by mail105.syd.optusnet.com.au (Postfix) with ESMTPS id 456CF3A2DDE; Wed, 22 Apr 2020 07:30:51 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92.3) (envelope-from ) id 1jR0Th-0006DL-Po; Wed, 22 Apr 2020 07:30:49 +1000 Date: Wed, 22 Apr 2020 07:30:49 +1000 From: Dave Chinner To: "Darrick J. Wong" Cc: ira.weiny@intel.com, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, Al Viro , Jan Kara , Dan Williams , Christoph Hellwig , "Theodore Y. Ts'o" , Jeff Moyer , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH V9 10/11] fs/xfs: Update xfs_ioctl_setattr_dax_invalidate() Message-ID: <20200421213049.GC27860@dread.disaster.area> References: <20200421191754.3372370-1-ira.weiny@intel.com> <20200421191754.3372370-11-ira.weiny@intel.com> <20200421203140.GD6742@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200421203140.GD6742@magnolia> User-Agent: Mutt/1.10.1 (2018-07-13) X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.3 cv=W5xGqiek c=1 sm=1 tr=0 a=XYjVcjsg+1UI/cdbgX7I7g==:117 a=XYjVcjsg+1UI/cdbgX7I7g==:17 a=kj9zAlcOel0A:10 a=cl8xLZFz6L8A:10 a=QyXUC8HyAAAA:8 a=7-415B0cAAAA:8 a=ATpMOFRGh5PMBAWjrYMA:9 a=CjuIK1q_8ugA:10 a=biEYGPWJfzWAr4FL6Ov7:22 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Apr 21, 2020 at 01:31:40PM -0700, Darrick J. Wong wrote: > On Tue, Apr 21, 2020 at 12:17:52PM -0700, ira.weiny@intel.com wrote: > > From: Ira Weiny > > > > Because of the separation of FS_XFLAG_DAX from S_DAX and the delayed > > setting of S_DAX, data invalidation no longer needs to happen when > > FS_XFLAG_DAX is changed. > > > > Change xfs_ioctl_setattr_dax_invalidate() to be > > xfs_ioctl_dax_check_set_cache() and alter the code to reflect the new > > functionality. > > > > Furthermore, we no longer need the locking so we remove the join_flags > > logic. > > > > Signed-off-by: Ira Weiny > > > > --- > > Changes from V8: > > Change name of function to xfs_ioctl_dax_check_set_cache() > > Update commit message > > Fix bit manipulations > > > > Changes from V7: > > Use new flag_inode_dontcache() > > Skip don't cache if mount over ride is active. > > > > Changes from v6: > > Fix completely broken implementation and update commit message. > > Use the new VFS layer I_DONTCACHE to facilitate inode eviction > > and S_DAX changing on drop_caches > > > > Changes from v5: > > New patch > > --- > > fs/xfs/xfs_ioctl.c | 108 +++++++++------------------------------------ > > 1 file changed, 20 insertions(+), 88 deletions(-) > > > > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > > index 104495ac187c..b87b571a6748 100644 > > --- a/fs/xfs/xfs_ioctl.c > > +++ b/fs/xfs/xfs_ioctl.c > > @@ -1245,64 +1245,26 @@ xfs_ioctl_setattr_xflags( > > return 0; > > } > > > > -/* > > - * If we are changing DAX flags, we have to ensure the file is clean and any > > - * cached objects in the address space are invalidated and removed. This > > - * requires us to lock out other IO and page faults similar to a truncate > > - * operation. The locks need to be held until the transaction has been committed > > - * so that the cache invalidation is atomic with respect to the DAX flag > > - * manipulation. > > - */ > > -static int > > -xfs_ioctl_setattr_dax_invalidate( > > +static void > > +xfs_ioctl_dax_check_set_cache( > > That's a ... strange name. Set cache on what? > > Oh, this is the function that sets I_DONTCACHE if an FS_XFLAG_DAX change > could have an immediate effect on S_DAX (assuming no other users). What > do you think of the following? > > /* > * If a change to FS_XFLAG_DAX will result in an change to S_DAX > * the next time the incore inode is initialized, set the VFS > * I_DONTCACHE flag to try to hurry that along. > */ > static void > xfs_ioctl_try_change_vfs_dax(...) That doesn't seem any better. This is a preparation function now, in that it can't fail and doesn't change the outcome of the operation being performed. So, IMO, calling it something like xfs_ioctl_setattr_prepare_dax() would be a better name for it. Cheers, Dave. -- Dave Chinner david@fromorbit.com