Re: [RFC] New locking primitive for 2.5

From: Alan Cox (alan@lxorguk.ukuu.org.uk)
Date: Fri Feb 08 2002 - 19:09:04 EST


> SMP 486s would need that (if there is such a beast). What point does x86
> get the 64 bit instructions? If after 586, then it would definately need a
> spinlock or somesuch in those functions.

There are SMP 486 class x86 machines that are MP 1.1 compliant. They are
sufficiently rare that I think its quite acceptable to "implement" a
cmpxchg8b macro on 486 as spin_lock_irqsave/blah/spin_unlock_irqrestore. It
would be wrong to cripple the other 99.99% of SMP users
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Fri Feb 15 2002 - 21:00:24 EST