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Date: Tue, 23 Oct 2012 14:06:41 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [patch v4 05/16] memory: introduce ref,
	unref interface for MemoryRegionOps
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To: Avi Kivity <avi@redhat.com>
Cc: Liu Ping Fan <pingfank@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@gmail.com>, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, Anthony Liguori <anthony@codemonkey.ws>, Jan Kiszka <jan.kiszka@siemens.com>

Il 23/10/2012 14:02, Avi Kivity ha scritto:
> On 10/23/2012 01:57 PM, Paolo Bonzini wrote:
>> Il 23/10/2012 13:55, Avi Kivity ha scritto:
>>>>> So the stop_machine idea is thrown away?  
>>> IIRC I convinced myself that it's just as bad.
>>
>> It may be just as bad, but it is less code (and less pervasive), which
>> makes it less painful.
> 
> It saves you the ->ref() and ->unref() calls, which are boilerplate, but
> not too onerous. All of the device model and subsystem threading work
> still needs to be done.

I'm not worried about saving the ->ref() and ->unref() calls in the
devices.  I'm worried about saving it in timers, bottom halves and
whatnot.  And also I'm not sure whether all callbacks would have
something to ref/unref as they are implemented now.

Paolo