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Date: Mon, 27 Aug 2012 23:34:32 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 10/10] qdev: fix create in place obj's life
	cycle problem
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To: Avi Kivity <avi@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>, Liu Ping Fan <pingfank@linux.vnet.ibm.com>, Liu Ping Fan <qemulist@gmail.com>, Anthony Liguori <anthony@codemonkey.ws>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

Il 27/08/2012 22:58, Avi Kivity ha scritto:
>> > It's best to start this conversion using very coarse locking.  There's
>> > no need to start with ultra fine grain locking.
> How does it work?  You have to drop this main loop lock to dispatch the
> callback, so the data structure you use for dispatch is no longer protected.

It is protected by a mixture of reference counting, thread-local storage and
careful coding to take care of re-entrancy.

I'm not too sure that we can use it, though.  Mostly because of the reasons Jan
mentioned (it may also not be precise enough, but we can fix that with our own
GSource wrapping POSIX real-time timers or Linux timerfds).

Paolo