From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751236AbeEVGlZ (ORCPT ); Tue, 22 May 2018 02:41:25 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:45072 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750954AbeEVGlV (ORCPT ); Tue, 22 May 2018 02:41:21 -0400 Date: Mon, 21 May 2018 23:41:18 -0700 From: Christoph Hellwig To: Kent Overstreet Cc: Mike Snitzer , Jens Axboe , 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 Subject: Re: [PATCH 00/13] convert block layer to bioset_init()/mempool_init() Message-ID: <20180522064118.GA18704@infradead.org> References: <20180521144703.GA19303@redhat.com> <4b343aef-e11c-73ba-1d88-7e73ca838cad@kernel.dk> <20180521150439.GA19379@redhat.com> <61e30dcf-a01c-f47d-087a-12930caf9aef@kernel.dk> <20180521151817.GA19454@redhat.com> <20180521160907.GA19553@redhat.com> <20180521173724.GG11495@kmo-pixel> <20180521182427.GA20013@redhat.com> <20180521233855.GI11495@kmo-pixel> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180521233855.GI11495@kmo-pixel> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 21, 2018 at 07:38:55PM -0400, Kent Overstreet wrote: > On Mon, May 21, 2018 at 02:24:32PM -0400, Mike Snitzer wrote: > > Every single data structure change in this series should be reviewed for > > unforeseen alignment consequences. Jens seemed to say that is > > worthwhile. Not sure if he'll do it or we divide it up. If we divide > > it up a temp topic branch should be published for others to inspect. > > > > Could be alignment hasn't been a historic concern for a bunch of the > > data structures changed in this series.. if so then all we can do is fix > > up any obvious potential for false sharing. > > Honestly, I almost never worry about alignment... the very few times I do care, > I use __cacheline_aligned_in_smp. And that generally is the right stratgey. If Mike really doesn't want a change we can just open code the kmalloc for the bio set there, the important point is that we should not keep the old API around for no good reason.