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SubjectRe: [patch] checksum P6 asm buffer overflow fix + 686 improvements
Hi!

> Yes it improved performances, but I am not sure if it worth since I still
> have to add the fpu_save trick.
>
> Adding the ftp_save trick should be quite easy, I think we could do only
> what we do in schedule:
>
> unlazy_fpu(current);
> mmx_checksum(); /* play with FPU as you like without saving */

You could do even more clever trick, something like

if (!current->used_math) {
unlazy_fpu(current);
mmx_checksum();
} else normal_checksum();

is pretty easy to do, yet it should work _very_ well.

> But with the mmx done as above if somebody is going to use opengl +
> network heavily then he will go slower than using the current cksum 686
> code (also considering the many exceptions that will generate the unlazy
> trick). A router alone probably will run faster instead but the
> improvement is not large enough to convince me to use MMX...

I think above method has no disadvantages ;-), what do you think?

Pavel

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