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Date: Mon, 07 Feb 2011 17:30:50 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] Re: [RFC: 0/2] patch for QEMU HPET periodic timer
	emulation to alleviate time drift
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: kvm <kvm@vger.kernel.org>, Glauber Costa <glommer@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, Ulrich Obergfell <uobergfe@redhat.com>

On 02/07/2011 05:20 PM, Jan Kiszka wrote:
> On 2011-02-07 16:13, Avi Kivity wrote:
> >>
> >>  PeriodicTimer *periodic_timer_new(PeriodicTimerFunc *cb, void *opaque);
> >>
> >
> >  void periodic_timer_init(PeriodicTimer *timer, PeriodicTimerFunc *cb);
> >
> >  It is better to embed than to reference.
>
> And embedding means making the layout (at least the size) of
> PeriodicTimer public. I guess that's why QEMUTimer works via new.

Why do we care?  We don't have an stable module interface.

(the way to provide a size-stable interface is

     struct PeriodicTimer {
         struct PeriodicTimerImpl *impl
     };

though of course it negates some of the advantages of embedding).

-- 
error compiling committee.c: too many arguments to function