From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Sterba Subject: Re: [PATCH 00/13] convert block layer to bioset_init()/mempool_init() Date: Mon, 21 May 2018 17:12:51 +0200 Message-ID: <20180521151251.GX6649@twin.jikos.cz> References: <20180520222558.7053-1-kent.overstreet@gmail.com> <20180521140348.GA19069@redhat.com> <686d7df6-c7d1-48a6-b7ff-48dc8aff6a62@kernel.dk> Reply-To: dsterba@suse.cz Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <686d7df6-c7d1-48a6-b7ff-48dc8aff6a62@kernel.dk> Sender: linux-kernel-owner@vger.kernel.org To: Jens Axboe Cc: Mike Snitzer , Kent Overstreet , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, hch@infradead.org, colyli@suse.de, darrick.wong@oracle.com, clm@fb.com, bacik@fb.com, linux-xfs@vger.kernel.org, drbd-dev@lists.linbit.com, linux-btrfs@vger.kernel.org, linux-raid@vger.kernel.org, neilb@suse.com List-Id: linux-raid.ids On Mon, May 21, 2018 at 08:19:58AM -0600, Jens Axboe wrote: > On 5/21/18 8:03 AM, Mike Snitzer wrote: > > On Sun, May 20 2018 at 6:25pm -0400, > > Kent Overstreet wrote: > > > >> Jens - this series does the rest of the conversions that Christoph wanted, and > >> drops bioset_create(). > >> > >> Only lightly tested, but the changes are pretty mechanical. Based on your > >> for-next tree. > > > > By switching 'mempool_t *' to 'mempool_t' and 'bio_set *' to 'bio_set' > > you've altered the alignment of members in data structures. So I'll > > need to audit all the data structures you've modified in DM. > > > > Could we get the backstory on _why_ you're making this change? > > Would go a long way to helping me appreciate why this is a good use of > > anyone's time. > > Yeah, it's in the first series, it gets rid of a pointer indirection. This should to be also mentioned the changelog of each patch. There are 12 subsystems changed, this could be about 10 maintainers and I guess everybody has the same question why the change is made. The conversion is not exactly the same in all patches, the simple pointer -> static variable can be possibly covered by the same generic text but as Mike points out the alignment changes should be at least mentioned for consideration otherwise.