From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 3ED1D7CBF for ; Mon, 16 Nov 2015 08:41:42 -0600 (CST) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay2.corp.sgi.com (Postfix) with ESMTP id 1836C30404E for ; Mon, 16 Nov 2015 06:41:41 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by cuda.sgi.com with ESMTP id pFDQmMhhGDmFZ4t9 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 16 Nov 2015 06:41:34 -0800 (PST) Date: Mon, 16 Nov 2015 15:41:30 +0100 From: Jan Kara Subject: Re: [PATCH v2 00/11] DAX fsynx/msync support Message-ID: <20151116144130.GD3443@quack.suse.cz> References: <1447459610-14259-1-git-send-email-ross.zwisler@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1447459610-14259-1-git-send-email-ross.zwisler@linux.intel.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Ross Zwisler Cc: Dave Hansen , "J. Bruce Fields" , linux-mm@kvack.org, Andreas Dilger , "H. Peter Anvin" , Jeff Layton , Dan Williams , linux-nvdimm@lists.01.org, x86@kernel.org, Ingo Molnar , Matthew Wilcox , linux-ext4@vger.kernel.org, xfs@oss.sgi.com, Alexander Viro , Thomas Gleixner , Theodore Ts'o , linux-kernel@vger.kernel.org, Jan Kara , linux-fsdevel@vger.kernel.org, Andrew Morton , Matthew Wilcox On Fri 13-11-15 17:06:39, Ross Zwisler wrote: > This patch series adds support for fsync/msync to DAX. > > Patches 1 through 7 add various utilities that the DAX code will eventually > need, and the DAX code itself is added by patch 8. Patches 9-11 update the > three filesystems that currently support DAX, ext2, ext4 and XFS, to use > the new DAX fsync/msync code. > > These patches build on the recent DAX locking changes from Dave Chinner, > Jan Kara and myself. Dave's changes for XFS and my changes for ext2 have > been merged in the v4.4 window, but Jan's are still unmerged. You can grab > them here: > > http://www.spinics.net/lists/linux-ext4/msg49951.html I had a quick look and the patches look sane to me. I'll try to give them more detailed look later this week. When thinking about the general design I was wondering: When we have this infrastructure to track data potentially lingering in CPU caches, would not it be a performance win to use standard cached stores in dax_io() and mark corresponding pages as dirty in page cache the same way as this patch set does it for mmaped writes? I have no idea how costly are non-temporal stores compared to cached ones and how would this compare to the cost of dirty tracking so this may be just completely bogus... Honza -- Jan Kara SUSE Labs, CR _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs