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Date: Fri, 16 Mar 2007 10:20:54 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>, Andrew Morton <akpm@linux-foundation.org>,
       linux-kernel@vger.kernel.org, virtualization@lists.osdl.org,
       xen-devel@lists.xensource.com, Chris Wright <chrisw@sous-sol.org>,
       Zachary Amsden <zach@vmware.com>, Rusty Russell <rusty@rustcorp.com.au>,
       Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: [patch 14/26] Xen-paravirt_ops: add common patching machinery
Message-ID: <20070316092054.GK23174@elte.hu>
References: <20070301232443.195603797@goop.org> <20070301232528.055105942@goop.org>
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* Jeremy Fitzhardinge <jeremy@goop.org> wrote:

> Implement the actual patching machinery.  paravirt_patch_default() 
> contains the logic to automatically patch a callsite based on a few 
> simple rules:
> 
>  - if the paravirt_op function is paravirt_nop, then patch nops
>  - if the paravirt_op function is a jmp target, then jmp to it
>  - if the paravirt_op function is callable and doesn't clobber too much
>     for the callsite, call it directly
> 
> paravirt_patch_default is suitable as a default implementation of 
> paravirt_ops.patch, will remove most of the expensive indirect calls 
> in favour of either a direct call or a pile of nops.

Acked-by: Ingo Molnar <mingo@elte.hu>

	Ingo