Messages in this thread | | | Date | Mon, 10 Nov 1997 11:16:09 +0000 (GMT/BST) | From | Mike Jagdis <> | Subject | Re: Pentium DEATH in user-mode |
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On Sat, 8 Nov 1997, Andre Derrick Balsa wrote:
> Setting the NO_LOCK bit in CCR1 will prevent the deadlock caused by the > above code sequence. Here is a short call to set6x86 that does this: > > set6x86 -p 0xc1 -s 0x10. > > Page table accesses and interrupt acknowledge cycles will still be > executed in locked cycles, but the xchgl instruction will *not* generate > locked cycles anymore. > > I don't know if setting the NO_LOCK bit will cause problems when running > Linux. I don't think so...
It doesn't. I don't think explicit locks can be relied on to be visible to anything that isn't sitting directly on the memory/CPU bus. The only time Linux cares whether explicit locks are honoured or not is when they are used to synchronize SMP systems. As far as I know there isn't yet a Cyrix based SMP design available.
Mike
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