From: Nick Piggin <npiggin@suse.de>
To: Jan Beulich <JBeulich@novell.com>
Cc: Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
hpa@zytor.com, linux-kernel@vger.kernel.org
Subject: Re: uses of cmpxchg/xadd in spinlock.h and rwsem.h vs. CONFIG_M386
Date: Tue, 12 May 2009 17:37:32 +0200 [thread overview]
Message-ID: <20090512153732.GA31131@wotan.suse.de> (raw)
In-Reply-To: <4A09AF8402000078000007DC@vpn.id2.novell.com>
On Tue, May 12, 2009 at 04:19:00PM +0100, Jan Beulich wrote:
> While looking at a completely different issue I happened to grep for uses of
> xadd, and it would appear to me that there got uses added that would make
> a M386-configured SMP kernel die on an actual i386.
>
> Oh, for the rwsem case I see - it would use the RWSEM_GENERIC_SPINLOCK case
> when selecting M386. But I see nothing similar for the ticket spinlocks - am
> I overlooking something?
Oh, hmm, we do actually attempt to support 386 SMP kernels... I thought
that config wasn't allowed, but looking at the atomic.h code, it has
ifdef fallbacks.
I guess some similar hacks could be added to spinlock.h code.
next prev parent reply other threads:[~2009-05-12 15:37 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-12 15:19 Jan Beulich
2009-05-12 15:37 ` Nick Piggin [this message]
2009-05-12 15:57 ` Alan Cox
2009-05-12 16:02 ` Peter Zijlstra
2009-05-12 15:51 ` H. Peter Anvin
2009-05-12 15:57 ` Nick Piggin
2009-05-12 16:04 ` H. Peter Anvin
2009-05-12 16:16 ` Jan Beulich
2009-05-12 16:18 ` Andreas Schwab
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