Re: Semaphore assembly-code bug

[linux-os]

On Fri, 29 Oct 2004, Andreas Steinmetz wrote:

> Linus Torvalds wrote:
> > On Fri, 29 Oct 2004, linux-os wrote:
> >
> > > Linus, please check this out.
> >
> >
> > Yes, I concur. However, I'd suggest changing the "addl $4,%esp" into a 
> > "popl %ecx", which is smaller and apparently faster on some CPU's (ecx 
> > obviously gets immediately overwritten by the next popl).
>
> Hmm, I didn't check the instruction length but modern CPUs usually work best 
> with the following:
>
> leal 4(%esp),%esp
>
> --
> Andreas Steinmetz                       SPAMmers use robotrap@xxxxxxxx

Probably so because I'm pretty certain that the 'pop' (a memory
access) is not going to be faster than a simple register operation.

I'll make another patch and post it (if the machine will boot!)

Cheers,
Dick Johnson
Penguin : Linux version 2.6.9 on an i686 machine (5537.79 BogoMips).
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