From: Rusty Russell <rusty@rustcorp.com.au>
To: "Glauber de Oliveira Costa" <glommer@gmail.com>
Subject: Re: [PATCH 0/16] lguest: introduce vcpu structure
Date: Mon, 7 Jan 2008 11:53:57 +1100
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Cc: "Glauber de Oliveira Costa" <gcosta@redhat.com>, lguest@ozlabs.org,
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On Monday 07 January 2008 04:33:53 Glauber de Oliveira Costa wrote:
> On Dec 25, 2007 9:54 PM, Rusty Russell <rusty@rustcorp.com.au> wrote:
> >     My only question is whether we should go further and vpu-ify routines
> > like lgread and kill_guest, so that we can avoid more "lg" temporary
> > variables...
>
> Essentially, they don't need it, because they only touch
> globally-visible variables (visible to the guest).
> So it's more of an stylish thing. Using the vcpu in the signature can
> have only one harm:
> It needs the caller to also have a pointer to a vcpu, so we may end up
> using it everywhere, like a domino fall.
>
> Alternatively, in such functions that don't currently receive a vcpu
> (nor they need to), we can convention to always pass
> lg->vcpus[0] to lgread, kill_guest, etc. Which one do you prefer?

I'm happy with a domino effect.  I don't want to see lg->vcpus[0] *anywhere* 
though, because it's non-futureproof.

When I looked through these patches it seems to me that we should accept that 
vcpu is now the basic guest unit, and lg exists to serve it.  Otherwise I 
think you can see the bones of the old UP code poking through, and that's 
ugly.

Thanks!
Rusty.
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