From: Ross Zwisler Subject: Re: [PATCH v4 00/12] re-enable DAX PMD support Date: Mon, 3 Oct 2016 12:54:03 -0600 Message-ID: <20161003185403.GD2044@linux.intel.com> References: <1475189370-31634-1-git-send-email-ross.zwisler@linux.intel.com> <20160929234345.GG27872@dastard> <20160930030343.GA12464@linux.intel.com> <20160930040055.GE9309@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Ross Zwisler , Dave Chinner , linux-kernel@vger.kernel.org, Theodore Ts'o , Alexander Viro , Andreas Dilger , Andrew Morton , Christoph Hellwig , Dan Williams , Jan Kara , Matthew Wilcox , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@ml01.01.org, linux-xfs@vger.kernel.org To: "Darrick J. Wong" Return-path: Content-Disposition: inline In-Reply-To: <20160930040055.GE9309@birch.djwong.org> Sender: owner-linux-mm@kvack.org List-Id: linux-ext4.vger.kernel.org On Thu, Sep 29, 2016 at 09:00:55PM -0700, Darrick J. Wong wrote: > On Thu, Sep 29, 2016 at 09:03:43PM -0600, Ross Zwisler wrote: > > On Fri, Sep 30, 2016 at 09:43:45AM +1000, Dave Chinner wrote: > > > Finally: none of the patches in your tree have reviewed-by tags. > > > That says to me that none of this code has been reviewed yet. > > > Reviewed-by tags are non-negotiable requirement for anything going > > > through my trees. I don't have time right now to review this code, > > > so you're going to need to chase up other reviewers before merging. > > > > > > And, really, this is getting very late in the cycle to be merging > > > new code - we're less than one working day away from the merge > > > window opening and we've missed the last linux-next build. I'd > > > suggest that we'd might be best served by slipping this to the PMD > > > support code to the next cycle when there's no time pressure for > > > review and we can get a decent linux-next soak on the code. > > > > I absolutely support your policy of only sending code to Linux that has passed > > peer review. > > > > However, I do feel compelled to point out that this is not new code. I didn't > > just spring it on everyone in the hours before the v4.8 merge window. I > > posted the first version of this patch set on August 15th, *seven weeks ago*: > > > > https://lkml.org/lkml/2016/8/15/613 > > > > This was the day after v4.7-rc2 was released. > > > > Since then I have responded promptly to the little review feedback > > that I've received. I've also reviewed and tested other DAX changes, > > like the struct iomap changes from Christoph. Those changes were > > first posted to the mailing list on September 9th, four weeks after > > mine. Nevertheless, I was happy to rebase my changes on top of his, > > which meant a full rewrite of the DAX PMD fault handler so it would be > > based on struct iomap. His changes are going to be merged for v4.9, > > and mine are not. > > I'm not knocking the iomap migration, but it did cause a fair amount of > churn in the XFS reflink patchset -- and that's for a filesystem that > already /had/ iomap implemented. It'd be neat to have all(?) the DAX > filesystems (ext[24], XFS) move over to iomap so that you wouldn't have > to support multiple ways of talking to FSes. AFAICT ext4 hasn't gotten > iomap, which complicates things. But that's my opinion, maybe you're > fine with supporting iomap and not-iomap. I agree that we want to move everything over to be iomap based. I think Christoph is already working on moving ext4 over, but as of this set PMD support explicitly depends on the iomap interface, and I'm itching to remove the struct buffer_head + get_block_t PTE path and I/O path as well. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org