From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: Re: [PATCH] domain builder: Fix sp_extents allocation
Date: Thu, 31 Jul 2008 12:29:21 +0100
Message-ID: <20080731112921.GF4678@implementation.uk.xensource.com>
References: <20080731111250.GE4678@implementation.uk.xensource.com>
	<C4B75E46.24E81%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>
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Keir Fraser, le Thu 31 Jul 2008 12:19:18 +0100, a =E9crit :
> Doesn't this turn the array allocation into a dynamic allocation? I fee=
l a
> bit dubious about that.

> >          {
> >              long done;
> > -            xen_pfn_t sp_extents[2048 >> SUPERPAGE_PFN_SHIFT];
> > +            xen_pfn_t sp_extents[count >> SUPERPAGE_PFN_SHIFT];
> >              struct xen_memory_reservation sp_req =3D {

Err, I'd think that it just turns a

sub (2048>>SUPERPAGE_PFN_SHIFT) * sizeof(xen_pfn_t), %esp

into a

mov count, %eax
shr SUPERPAGE_PFN_SHIFT - log2(sizeof(xen_pfn_t)), %eax
sub %eax, %esp

Samuel