Re: Intel P6 vs P7 system call performance

Linus Torvalds
2002-12-18T04:07:05Z

On Tue, 17 Dec 2002, Linus Torvalds wrote:
>
> How about this diff? It does both the 6-parameter thing _and_ the
> AT_SYSINFO addition.

The 6-parameter thing is broken. It's clever, but playing games with %ebp
is not going to work with restarting of the system call - we need to
restart with the proper %ebp.

I pushed out the AT_SYSINFO stuff, but we're back to the "needs to use
'int $0x80' for system calls that take 6 arguments" drawing board.

The only sane way I see to fix the %ebp problem is to actually expand the
kernel "struct ptregs" to have separate "ebp" and "arg6" fields (so that
we can re-start with the right ebp, and have arg6 as the right argument on
the stack). That would work but is not really worth it.

Linus