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Date: Thu, 20 Jun 2013 09:46:03 +0200
From: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20130620074603.GC15082@stefanha-thinkpad.redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 2/6] net: introduce lock to protect
 NetClientState's peer's access
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To: liu ping fan <qemulist@gmail.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org, mdroth <mdroth@linux.vnet.ibm.com>

On Thu, Jun 20, 2013 at 02:30:30PM +0800, liu ping fan wrote:
> On Tue, Jun 18, 2013 at 8:25 PM, Stefan Hajnoczi <stefanha@gmail.com> wrote:
> > On Thu, Jun 13, 2013 at 05:03:02PM +0800, Liu Ping Fan wrote:
> >> + * And flush out peer's queue.
> >> + */
> >> +static void qemu_net_client_detach_flush(NetClientState *nc)
> >> +{
> >> +    NetClientState *peer;
> >> +
> >> +    /* reader of self's peer field , fixme? the deleters are not concurrent,
> >> +         * so this pair lock can save.
> >> +         */
> >
> > Indentation, also please resolve the fixme.
> >
> So, here can I take the assumption that the deleters are serialized by
> biglock, and remove the lock following this comment?

Ah, I understand the comment now.  Is there any advantage to dropping
the lock?  IMO it's clearer to take the lock consistently instead of
"optimizing" cases we think only get called from the main loop.