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Date: Wed, 9 Apr 2014 19:16:07 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>, Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH 1/5] sched: Convert thread_group_cputime() to use
 for_each_thread()
Message-ID: <20140409171607.GA13498@dyad.arnhem.chello.nl>
References: <1397059882-23063-1-git-send-email-fweisbec@gmail.com>
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On Wed, Apr 09, 2014 at 06:11:18PM +0200, Frederic Weisbecker wrote:
> do_each_thread/while_each_thread iterators are deprecated by
> for_each_thread/for_each_process_thread() APIs.
> 
> Lets convert the callers in the cputime code accounting. The ultimate
> goal is to remove the struct task_struct::thread_group field and
> the corresponding do_each_thread/while_each_thread iterators that are
> RCU unsafe.
> 
> It also makes thread_group_cputime() eventually RCU-safe.

this fails to explain how the current code is broken.