From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: [PATCH] percpu ida: Switch to cpumask_t, add some comments Date: Wed, 28 Aug 2013 14:00:10 -0700 Message-ID: <20130828210010.GD1357@kmo-pixel> References: <1376694549-20609-1-git-send-email-nab@linux-iscsi.org> <1376694549-20609-2-git-send-email-nab@linux-iscsi.org> <20130820143157.f91bf59d16352989b54e431e@linux-foundation.org> <20130828195517.GF8032@kmo-pixel> <20130828132550.d0ce4d3a4d40ee07e7e8a1c1@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jens Axboe , Andi Kleen , kvm-devel , "Michael S. Tsirkin" , lkml , lf-virt , target-devel , Christoph Lameter , Oleg Nesterov , Tejun Heo , Christoph Lameter , Ingo Molnar To: Andrew Morton Return-path: Content-Disposition: inline In-Reply-To: <20130828132550.d0ce4d3a4d40ee07e7e8a1c1@linux-foundation.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: kvm.vger.kernel.org On Wed, Aug 28, 2013 at 01:25:50PM -0700, Andrew Morton wrote: > On Wed, 28 Aug 2013 12:55:17 -0700 Kent Overstreet wrote: > > > Fixup patch, addressing Andrew's review feedback: > > Looks reasonable. > > > lib/idr.c | 38 +++++++++++++++++++++----------------- > > I still don't think it should be in this file. > > You say that some as-yet-unmerged patches will tie the new code into > the old ida code. But will it do it in a manner which requires that > the two reside in the same file? Not require, no - but it's just intimate enough with my ida rewrite that I think it makes sense; it makes some use of stuff that should be internal to the ida code. Mostly just sharing the lock though, since I got rid of the ida interfaces that don't do locking, but percpu ida needs a lock that also covers what ida needs. It also makes use of a ganged allocation interface, but there's no real reason ida can't expose that, it's just unlikely to be useful to anything but percpu ida. The other reason I think it makes sense to live in idr.c is more for users of the code; as you pointed out as far as the user's perspective percpu ida isn't doing anything fundamentally different from ida, so I think it makes sense for the code to live in the same place as a kindness to future kernel developers who are trying to find their way around the various library code.