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Date: Wed, 23 Nov 2011 08:44:31 -0800
From: Tejun Heo <tj@kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Ingo Molnar <mingo@redhat.com>, Jiri Olsa <jolsa@redhat.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] trace_events_filter: use rcu_assign_pointer() when
 setting ftrace_event_call->filter
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Hello,

On Wed, Nov 23, 2011 at 05:40:17PM +0100, Eric Dumazet wrote:
> > -		call->filter = NULL;
> > +		rcu_assign_pointer(call->filter, NULL);
> 
> Its a minor point, but setting a pointer to NULL certainly doesnt need a
> smp_wmb() barrier, so you can use RCU_INIT_POINTER(call->filter, NULL);

Yeap, we don't need it for NULL.  Did that anyway for consistency /
documentation.  Didn't know we had a macro for that.  Neat.  Updating
the patch....

Thanks.

-- 
tejun