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Date: Wed, 7 Mar 2012 18:09:17 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [patch 1/2] mm, counters: remove task argument to sync_mm_rss
 and __sync_task_rss_stat
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On Wed, 7 Mar 2012 17:40:04 -0800 (PST) David Rientjes <rientjes@google.com> wrote:

> On Wed, 7 Mar 2012, Andrew Morton wrote:
> 
> > hm, with my gcc it's beneficial to cache `current' in a local.  But
> > when I tried that, Weird Things happened, because gcc has gone and
> > decided to inline __sync_task_rss_stat() into its callers.  I don't see
> > how that could have been the right thing to do.
> > 
> 
> c06b1fca18c3 offers some advice :)

But is it right?  I handled a patch a month or two ago where caching
current made a nice improvement.