From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx147.postini.com [74.125.245.147]) by kanga.kvack.org (Postfix) with SMTP id 7D28B6B0044 for ; Fri, 2 Nov 2012 19:31:16 -0400 (EDT) Received: by mail-ia0-f169.google.com with SMTP id h37so3769621iak.14 for ; Fri, 02 Nov 2012 16:31:15 -0700 (PDT) Date: Fri, 2 Nov 2012 16:31:18 -0700 (PDT) From: Hugh Dickins Subject: Re: [PATCH] memcg: fix hotplugged memory zone oops In-Reply-To: <20121102102159.GA24073@dhcp22.suse.cz> Message-ID: References: <505187D4.7070404@cn.fujitsu.com> <20120913205935.GK1560@cmpxchg.org> <507CF789.6050307@cn.fujitsu.com> <20121018220306.GA1739@cmpxchg.org> <20121102102159.GA24073@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Andrew Morton , Johannes Weiner , Wen Congyang , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Jiang Liu , bsingharora@gmail.com, KAMEZAWA Hiroyuki , Konstantin Khlebnikov , paul.gortmaker@windriver.com, Tang Chen On Fri, 2 Nov 2012, Michal Hocko wrote: > > OK, it adds "an overhead" also when there is no hotadd going on but this > is just one additional mem access&cmp&je so it shouldn't be noticable > (lruvec->zone is used most of the time later so it not a pointless > load). I think so too. > It is also easier to backport for stable. Yes. > But is there any reason to fix it later properly in the hotadd hook? I don't know. Not everybody liked it fixed this way: it's not unreasonable to see this as a quick hack rather than the right fix. I was expecting objectors to post alternative hotadd hook patches, then we could compare and decide. That didn't happen; but we can certainly look to taking out these lines later if something we agree is better comes along. Not high on anyone's agenda, I think. > > Anyway > Acked-by: Michal Hocko Thanks, Hugh -- 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