From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932837Ab2IDWkg (ORCPT ); Tue, 4 Sep 2012 18:40:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57582 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757813Ab2IDWke (ORCPT ); Tue, 4 Sep 2012 18:40:34 -0400 Date: Wed, 5 Sep 2012 00:40:27 +0200 From: Andrea Arcangeli To: Andrew Morton Cc: Martin Schwidefsky , Gerald Schaefer , Andi Kleen , Hugh Dickins , Hillf Danton , linux-kernel@vger.kernel.org, Heiko Carstens Subject: Re: [RFC v2 PATCH 0/7] thp: transparent hugepages on s390 Message-ID: <20120904224027.GM3334@redhat.com> References: <1346254384-30046-1-git-send-email-gerald.schaefer@de.ibm.com> <20120830125444.86925ef3.akpm@linux-foundation.org> <20120831090757.2e29c834@de.ibm.com> <20120831124702.8980b637.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120831124702.8980b637.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andrew and Martin, On Fri, Aug 31, 2012 at 12:47:02PM -0700, Andrew Morton wrote: > On Fri, 31 Aug 2012 09:07:57 +0200 > Martin Schwidefsky wrote: > > > > I grabbed them all. Patches 1-3 look sane to me and I cheerfully > > > didn't read the s390 changes at all. Hopefully Andrea will be able to > > > review at least patches 1-3 for us. > > > > > > If that all goes well, how do we play this? I'd prefer to merge 1-3 > > > myself, as they do interact with ongoing MM development. I can also > > > merge 4-7 if appropriate s390 maintainer acks are seen. Or I can drop > > > them and the s390 parts can be merged via the s390 tree at a later > > > date? > > > > I would really appreciate if Andrea could have a look at the code. > > Yes please ;) :) Sorry for the delay! I was at the Plumbers until last Friday and I'm catching up with the emails. I finished reviewing them and they look perfectly fine. In fact it was a pleasure to read them. Patch 1 and 2 are noops in x86 context, patch 3 is fine as well. The s390 solution to send a dummy IPIs to wait gup-fast to exit the critical section after setting the splitting bit looks fine as well. The only additional code cleanup suggestion I can give is to also add a HAVE_ARCH_TRANSPARENT_HUGEPAGE on the same lines of: http://git.kernel.org/?p=linux/kernel/git/andrea/aa.git;a=commitdiff;h=36c2d096cce61fcfc1726ea1c1fd6dd65ddf8b08;hp=b2a86603629e2401d85f9ed1acbcf6c0043b2b23 as patch 8. In order to convert the below: + depends on (X86 || (S390 && 64BIT)) && MMU to: depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE The MMU check looks already superflous, even more so after adding the HAVE_ARCH_TRANSPARENT_HUGEPAGE (if something it'll be up to the arch code to add a dependency on it before defining HAVE_ARCH_). Thanks, Andrea