From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 40DA1900137 for ; Tue, 9 Aug 2011 06:00:40 -0400 (EDT) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id E55213EE0AE for ; Tue, 9 Aug 2011 19:00:36 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id C862345DEB7 for ; Tue, 9 Aug 2011 19:00:36 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id AC4A145DEB4 for ; Tue, 9 Aug 2011 19:00:36 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 9BFFF1DB8037 for ; Tue, 9 Aug 2011 19:00:36 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.240.81.134]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 5F30C1DB8041 for ; Tue, 9 Aug 2011 19:00:36 +0900 (JST) Date: Tue, 9 Aug 2011 18:53:13 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH RFC] memcg: fix drain_all_stock crash Message-Id: <20110809185313.dc784d70.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110809094503.GD7463@tiehlicka.suse.cz> References: <20110808184738.GA7749@redhat.com> <20110808214704.GA4396@tiehlicka.suse.cz> <20110808231912.GA29002@redhat.com> <20110809072615.GA7463@tiehlicka.suse.cz> <20110809093150.GC7463@tiehlicka.suse.cz> <20110809183216.97daf2b0.kamezawa.hiroyu@jp.fujitsu.com> <20110809094503.GD7463@tiehlicka.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Johannes Weiner , linux-mm@kvack.org, Balbir Singh , Andrew Morton , linux-kernel@vger.kernel.org On Tue, 9 Aug 2011 11:45:03 +0200 Michal Hocko wrote: > On Tue 09-08-11 18:32:16, KAMEZAWA Hiroyuki wrote: > > On Tue, 9 Aug 2011 11:31:50 +0200 > > Michal Hocko wrote: > > > > > What do you think about the half backed patch bellow? I didn't manage to > > > test it yet but I guess it should help. I hate asymmetry of drain_lock > > > locking (it is acquired somewhere else than it is released which is > > > not). I will think about a nicer way how to do it. > > > Maybe I should also split the rcu part in a separate patch. > > > > > > What do you think? > > > > > > I'd like to revert 8521fc50 first and consider total design change > > rather than ad-hoc fix. > > Agreed. Revert should go into 3.0 stable as well. Although the global > mutex is buggy we have that behavior for a long time without any reports. > We should address it but it can wait for 3.2. > What "buggy" means here ? "problematic" or "cause OOps ?" > > Personally, I don't like to have spin-lock in per-cpu area. > > spinlock is not that different from what we already have with the bit > lock. maybe. The best is lockless style...but pointer in percpu cache is problem.. Thanks, -Kame -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org