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Date: Tue, 18 Jun 2013 11:31:07 +0200
From: Stefan Hajnoczi <stefanha@gmail.com>
Message-ID: <20130618093107.GB7649@stefanha-thinkpad.redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 2/2] QEMUBH: make AioContext's bh
 re-entrant
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To: liu ping fan <qemulist@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org, Anthony Liguori <anthony@codemonkey.ws>

On Tue, Jun 18, 2013 at 10:19:40AM +0800, liu ping fan wrote:
> On Mon, Jun 17, 2013 at 11:28 PM, Stefan Hajnoczi <stefanha@gmail.com> wrote:
> > On Sun, Jun 16, 2013 at 07:21:21PM +0800, Liu Ping Fan wrote:
> > Why lock bh_lock before assigning bh->next?  Could you lock the mutex
> > here and then drop the smp_wmb() since the pthread function already does
> > that?
> >
> As Paolo's explain, it will open race gap for writers.

Right, thanks!