Re: Intel P6 vs P7 system call performance

[Richard B. Johnson]

On Tue, 17 Dec 2002, Manfred Spraul wrote:

> >
> >
> >   pushl %ebp
> >   movl $0xfffff000, %ebp
> >   call *%ebp
> >   popl %ebp
> >  
> >
> 
> You could avoid clobbering a register with something like
> 
> pushl $0xfffff000
> call *(%esp)
> addl %esp,4
> 

This is a near 'call'.

	pushl $0xfffff000
	ret

This is a 'far' 'call' that I think you will need to reload the segment
back to user-mode segments on the return.

	pushl	$KERNEL_CS
	pushl	$0xfffff000
	lret

Cheers,
Dick Johnson
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