From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH -rt] memcg: use migrate_disable()/migrate_enable( ) in
 memcg_check_events()
Date: Wed, 16 Nov 2011 19:23:43 -0500
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Cc: Luis Henriques <henrix@camandro.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Yong Zhang <yong.zhang0@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-rt-users <linux-rt-users@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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On Thu, 2011-11-17 at 08:48 +0900, KAMEZAWA Hiroyuki wrote:

> > I run a quick test and it looks like the problem is gone.
> > 
> > Cheers,
> 
> Could you CC the final patch to cgroups@vger.kernel.org ?
> Does this fix will go thorugh rt tree rather than -mm ?

This particular fix only goes through the rt tree because it is only a
bug when full rt is enabled. When rt is enabled, spin_locks become
mutexes, and thus can not be used when preemption is disabled. The rt
tree introduced a local_lock() to remove open coded preempt disabling
and also to help annotate places that need per cpu protections.

-- Steve