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Date: Sun, 12 Sep 2010 15:26:51 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 3/3] disk: don't read from disk until the
	guest	starts
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, Juan Quintela <quintela@redhat.com>

  On 09/12/2010 03:08 PM, Anthony Liguori wrote:
>> This can cause a disk read, no?  Shouldn't it be made asynchronous?
>
>
> Yes, it should.  I'm not sure there's an easy way to make it 
> asynchronous though not because of the block layer but because of how 
> these functions are called.

Sorry to harp on the subject, but that's the standard problem with state 
machines.  Every time you want to do a blocking operation in a function, 
you have to put all its locals in some structure, split the function 
into two, do some scheduling, etc.

>>
>> Or just move it to just before the guest starts?
>
> We don't really have a notion of "guest starts" today although maybe 
> we should.

Wasn't there some qdev callback that represents this?  Faint memory from 
the reset thread.

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