Messages in this thread | | | Date | Thu, 30 Dec 1999 19:19:58 +0100 (CET) | From | Rik van Riel <> | Subject | Re: spin_unlock optimization |
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On Thu, 30 Dec 1999, Gabor Lenart wrote: > On Wed, Dec 29, 1999 at 07:44:02PM +0100, Oliver Henning wrote:
> > as was mentioned on Kernel Traffic, the spin_unlock optimization (movb $0,%0 > > instead of lock; btrl $0,%0) is not used at last. But could there be a > > detection routine (I know this is not a completely new and innovative idea) > > for those older PPro CPUs that require the slow version so that in the sane > > cases the optimization would be used. > > Yes. Runtime option is not acceptable imho. movb $0,%0 can be fast > but if you need a conditional instruction to test if the fast > version can be used uses more and more cycles.
Self-modifying code?
/me runs
Rik -- The Internet is not a network of computers. It is a network of people. That is its real strength.
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