Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754308Ab3HBUbc (ORCPT ); Fri, 2 Aug 2013 16:31:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:30997 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753701Ab3HBUbb (ORCPT ); Fri, 2 Aug 2013 16:31:31 -0400 Date: Fri, 2 Aug 2013 21:59:59 +0200 From: Andrea Arcangeli To: Johannes Weiner Cc: Andrew Morton , Mel Gorman , Rik van Riel , Zlatko Calusic , Minchan Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch v2 0/3] mm: improve page aging fairness between zones/nodes Message-ID: <20130802195959.GF26919@redhat.com> References: <1375457846-21521-1-git-send-email-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1375457846-21521-1-git-send-email-hannes@cmpxchg.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 968 Lines: 29 On Fri, Aug 02, 2013 at 11:37:23AM -0400, Johannes Weiner wrote: > Changes in version 2: v2 looks great to me. zone->alloc_batch -= 1U << order; 3147: d3 e0 shl %cl,%eax 3149: 29 42 54 sub %eax,0x54(%rdx) gcc builds it as one asm insn too. Considering we depend on gcc to be optimal and to update ptes in a single insn (and if it doesn't we'll corrupt memory), keeping it in C should always provide the update in a single insn. I believe the error introduced when mulptiple CPUs of the same NUMA node step on each other is going to be unmeasurable. ACK the whole series. Signed-off-by: Andrea Arcangeli Thanks, Andrea -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/