From: Nick Piggin <npiggin@suse.de>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@novell.com>, Ingo Molnar <mingo@elte.hu>,
Thomas Gleixner <tglx@linutronix.de>,
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 17:57:02 +0200 [thread overview]
Message-ID: <20090512155702.GB31131@wotan.suse.de> (raw)
In-Reply-To: <4A099AF0.8020001@zytor.com>
On Tue, May 12, 2009 at 08:51:12AM -0700, H. Peter Anvin wrote:
> 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?
>
> It's quite possible we break 386 on a regular basis... I'm not sure how
> many people even in the embedded industry run current kernels on
> 386-compatible hardware. Most embedded hardware is at least 486.
Is it time to get rid of attempts to support SMP kernels that run on 386, then?
Considering we don't actually support SMP 386, and if there is any 386 systems
then they're going to be running custom kernels anyway.
next prev parent reply other threads:[~2009-05-12 15:57 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
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 [this message]
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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