From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f174.google.com (mail-wi0-f174.google.com [209.85.212.174]) by kanga.kvack.org (Postfix) with ESMTP id AF53482F64 for ; Thu, 1 Oct 2015 03:35:55 -0400 (EDT) Received: by wicfx3 with SMTP id fx3so19366484wic.1 for ; Thu, 01 Oct 2015 00:35:55 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id ph6si2074193wic.113.2015.10.01.00.35.54 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 01 Oct 2015 00:35:54 -0700 (PDT) Subject: Re: [PATCH 03/10] mm, page_alloc: Remove unnecessary taking of a seqlock when cpusets are disabled References: <1442832762-7247-1-git-send-email-mgorman@techsingularity.net> <1442832762-7247-4-git-send-email-mgorman@techsingularity.net> From: Vlastimil Babka Message-ID: <560CE255.80303@suse.cz> Date: Thu, 1 Oct 2015 09:35:49 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes , Mel Gorman Cc: Andrew Morton , Johannes Weiner , Rik van Riel , Joonsoo Kim , Michal Hocko , Linux-MM , LKML On 10/01/2015 12:22 AM, David Rientjes wrote: > On Mon, 21 Sep 2015, Mel Gorman wrote: >> @@ -115,6 +118,9 @@ static inline unsigned int read_mems_allowed_begin(void) >> */ >> static inline bool read_mems_allowed_retry(unsigned int seq) >> { >> + if (!cpusets_enabled()) >> + return false; >> + >> return read_seqcount_retry(¤t->mems_allowed_seq, seq); >> } >> > > I thought this was going to test nr_cpusets() <= 1? That was another patch in prior iteration of the series, but turns out it was unnecessary, because cpusets_enabled() is already only true when nr_cpusets() > 1 - see https://lkml.org/lkml/2015/8/25/300 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org