From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [PATCH] xen: cache current vcpu
Date: Tue, 30 Oct 2007 10:54:15 +0000
Message-ID: <47271B67.76E4.0078.0@novell.com>
References: <200710291643.45546.Christoph.Egger@amd.com>
	<C34BC77D.17957%Keir.Fraser@cl.cam.ac.uk>
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To: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>
Cc: Christoph Egger <Christoph.Egger@amd.com>, xen-devel@lists.xensource.com
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>>> Keir Fraser <Keir.Fraser@cl.cam.ac.uk> 29.10.07 18:23 >>>
>Gcc is quite capable of eliminating common subexpressions involving
>current(), ...

I have to partly disagree here: While gcc is capable of doing this, it =
cannot
do anything about uses of current that have function calls in between, and
I also don't think making get_current() an __attribute__((__pure__)) =
inline
function would be correct.

I do agree that in certain places using current is more readable, albeit I
think that there are quite a few places where it is already non-obvious =
that
'v' denotes 'current' (perhaps naming might just help here - if 'v' only =
ever
gets set from 'current' in a function, renaming it to 'cur' might be =
reasonable
to consider).

Jan