From mboxrd@z Thu Jan  1 00:00:00 1970
From: paulmck@linux.vnet.ibm.com (Paul E. McKenney)
Date: Wed, 16 Jun 2010 08:53:16 -0700
Subject: [ltt-dev] [PATCH RFC] Force build failure on unknown
	architectures
In-Reply-To: <4C18C236.3030100@redhat.com>
References: <20100615231423.GA16064@linux.vnet.ibm.com>
	<4C1812E1.5080103@redhat.com>
	<20100616001228.GM2304@linux.vnet.ibm.com>
	<4C18C236.3030100@redhat.com>
Message-ID: <20100616155316.GA2457@linux.vnet.ibm.com>

On Wed, Jun 16, 2010 at 02:23:18PM +0200, Paolo Bonzini wrote:
> On 06/16/2010 02:12 AM, Paul E. McKenney wrote:
> >On Wed, Jun 16, 2010 at 01:55:13AM +0200, Paolo Bonzini wrote:
> >>On 06/16/2010 01:14 AM, Paul E. McKenney wrote:
> >>>Create urcu/arch_unknown.h and urcu/uatomic_arch_unknown.h, which
> >>>contain only #error statements and explanatory comments.  This forces
> >>>build failures on unrecognized architectures in preference to trying
> >>>to guess at what operations might be safe on such architectures.
> >>>
> >>>One other semi-feasible alternative is to use hashed arrays of locks
> >>>that are acquired with signals disabled.  However, this seems a bit
> >>>too ornate, especially for architectures for which the gcc __sync_
> >>>primitives work correctly.
> >>
> >>ia64 is one.
> >
> >Does ia64 work with the current code?  (My guess is "no" -- I believe
> >that you would get build errors.  But I have been surprised before!)
> 
> I don't know. :)
> 
> >If my guess is correct, my thought would be to create urcu/arch_gcc.h
> >and urcu/uatomic_arch_gcc.h files with the appropriate definitions
> >based on __sync_ primitives.  If you can test on IA64, I would also
> >be happy to add support for it based on these new files.
> 
> Sure, thanks!

Very good!!!

What does "uname -m" say on IA46?  My guess is "ia64", but figured that
I should ask.  ;-)

							Thanx, Paul