From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olaf Hering <olaf@aepfle.de>
Subject: Re: [PATCH] tools/libxc: make volatile keyword for
 bitmap operations optional
Date: Mon, 30 Jan 2012 11:26:21 +0100
Message-ID: <20120130102621.GB9935@aepfle.de>
References: <20120130091002.GA29543@aepfle.de>
	<CB4C13A9.29F65%keir.xen@gmail.com>
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To: Keir Fraser <keir.xen@gmail.com>
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On Mon, Jan 30, Keir Fraser wrote:

> On 30/01/2012 09:10, "Olaf Hering" <olaf@aepfle.de> wrote:
> > Will gcc use the right thing if the array is passed to the hyperviso,
> > and will it reload everything after the hypercall? If yes, the volatile
> > can indeed go.
> 
> Of course. Lots of things would fail to work if calls to outside the current
> linkage unit didn't flush/invalidate cached shared-data accesses. That's a
> fundamental C compiler thing.

You are right, after thinking about it I came to the same conclusion.
I will send an updated patch.

Olaf