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Date: Thu, 2 Oct 2014 11:24:28 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Kirill Tkhai <ktkhai@parallels.com>
Cc: Sasha Levin <sasha.levin@oracle.com>, mingo@kernel.org,
        torvalds@linux-foundation.org, paulmck@linux.vnet.ibm.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched: Use RCU read lock on all calls to dl_bw_of()
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On Tue, Sep 30, 2014 at 12:23:37PM +0400, Kirill Tkhai wrote:
> [PATCH]sched: Use dl_bw_of() under preempt_disable()
> 
> rq->rd is freed using call_rcu_sched(), so rcu_read_lock() to access it
> is not enough. We should use either rcu_read_lock_sched() or preempt_disable().
> 
> We choose preempt_disable()/preempt_enable() like in other places
> where rq->rd is used.

I changed it to rcu_read_lock_sched(), but no biggie, thanks!