From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: [PATCH v2] xen: arm32: reduce default size of the
	xenheap
Date: Thu, 5 Feb 2015 15:34:31 +0000
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To: Julien Grall <julien.grall@linaro.org>
Cc: stefano.stabellini@eu.citrix.com, tim@xen.org, Jintack Lim <jintack@cs.columbia.edu>, Jan Beulich <JBeulich@suse.com>, xen-devel@lists.xen.org
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On Thu, 2015-02-05 at 22:01 +0800, Julien Grall wrote:
> If the user requests a xenheap of 0MB, we will use the default size, 
> right? It may be worth to explain this case.

I think it's pretty generally understood that 0 generally means the
default, unless otherwise specified.

> Also with the algorithm to find a range, the Xen heap may be smaller. I 
> would explain that too.

True.

> > +        xenheap_pages = opt_xenheap_megabytes << (20-PAGE_SHIFT);
> > +    else
> > +    {
> > +        xenheap_pages = (heap_pages/32 + 0x1fffUL) & ~0x1fffUL;
> > +        xenheap_pages = max(xenheap_pages, 32UL<<(20-PAGE_SHIFT));
> > +        xenheap_pages = min(xenheap_pages, 1UL<<(30-PAGE_SHIFT));
> > +    }
> >       do
> >       {
> 
> You seem to have forgotten to update the condition in the do/while:
> 
> xenheap_pages > 128 << (20 - PAGE_SHIFT);

Seems like I need to refactor this number into a constant somewhere.

Ian.