Re: 2.6.17-rc1-mm1: KEXEC became SMP-only

From: Andrew Morton <akpm@osdl.org>
To: Zachary Amsden <zach@vmware.com>
Cc: ebiederm@xmission.com, bunk@stusta.de,
	linux-kernel@vger.kernel.org, rdunlap@xenotime.net,
	fastboot@osdl.org
Subject: Re: 2.6.17-rc1-mm1: KEXEC became SMP-only
Date: Tue, 4 Apr 2006 15:38:48 -0700	[thread overview]
Message-ID: <20060404153848.55c4811a.akpm@osdl.org> (raw)
In-Reply-To: <4432F469.1040405@vmware.com>

Zachary Amsden <zach@vmware.com> wrote:
>
> Do weak symbols work with all tool chains?
> 

I hope so.  `grep weak */*.c'.

> >   
> >> 2) You don't need #ifdef SUBARCH_FUNC_FOO goo to do this (renaming 
> >> voyager_halt -> default)
> >>     
> >
> > Why would one need that?  Isn't it simply a matter of renaming
> > machine_halt() to subarch_machine_halt() everywhere?
> >   
> 
> No - if you rename machine_halt to subarch_machine_halt, you again can't 
> add a new subarch interface without changing all subarchitectures.  If I 
> add voyager_smp_bless_voyage(), I now need to add #define 
> visws_smp_bless_voyage default_smp_bless_voyage, ... or did you mean 
> subarch_machine_halt literally?

Yes, I meant subarch_machine_halt() literally.

> > I'm just looking for the simplest option here.  Eric has identified a code
> > maintainability problem - it'd be good to fix that, but we shouldn't add
> > runtime cost/complexity unless we actually gain something from it.
> >   
> 
> I think weak symbols are the best approach, if they indeed work with all 
> tool chains.

They do.