Message-ID: <47B0EE46.6050208@zytor.com>
Date: Mon, 11 Feb 2008 16:54:30 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Matt Mackall <mpm@selenic.com>
CC: Michael Opdenacker <michael-lists@free-electrons.com>,
       Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>,
       Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
       Linux-tiny@selenic.com
Subject: Re: [PATCH] x86 (Linux Tiny): configure out support for	some	processors
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Matt Mackall wrote:
> On Mon, 2008-02-11 at 15:01 -0800, H. Peter Anvin wrote:
>> Matt Mackall wrote:
>>> Best would be to have no ifdefs and do it all with linker magic, of
>>> course. But that's trickier.
>>>
>> I concur with this, definitely.
> 
> Ok, so let's come up with a plan. We can:
> 
> a) use weak symbols, ala cond_syscall
> b) use a special section
> c) use early_init code (is it early enough?)
> c) have some sort of registration list
> 
> Having a generic cond_call of some sort might be nice for this sort of
> thing.
> 

c) is out, because this has to be executed after the early generic code 
and before the late generic code.

b) would be my first choice, and yes, it would be a good thing to have a 
generalized mechanism for this.  For the registrant, it's pretty easy: 
just add a macro that adds a pointer to a named section.  We then need a 
way to get the base address and length of each such section in order to 
be able to execute each function in sequence.

	-hpa

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