From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [RFC/PATCH] XENMEM_claim_pages (subop of an
	existing) hypercall
Date: Wed, 14 Nov 2012 07:23:56 +0000
Message-ID: <CCC8F78C.44A23%keir.xen@gmail.com>
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To: Dan Magenheimer <dan.magenheimer@oracle.com>, Jan Beulich <JBeulich@suse.com>, TimDeegan <tim@xen.org>
Cc: Zhigang Wang <zhigang.x.wang@oracle.com>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, xen-devel@lists.xen.org
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On 13/11/2012 22:23, "Dan Magenheimer" <dan.magenheimer@oracle.com> wrote:

> The key variables (d->unclaimed_pages and total_unclaimed_pages)
> start at zero if no claim has yet been staked for any domain.
> (Perhaps a better name is "claimed_but_not_yet_possessed" but that's
> a bit unwieldy.)  If no claim hypercalls are executed, there
> should be no impact on existing usage.

It would be nice if d->tot_pages adjustments didn't take the global
heap_lock in this case. There's probably some way to bail out of those new
update functions before doing the locked work, in that case.

 -- Keir