Re: [Bug 350] New: i386 context switch very slow compared to 2.4 due to wrmsr (performance)

Linus Torvalds
2003-02-12T17:17:44Z

In article <20030212101831.GB10422@bjl1.jlokier.co.uk>,
Jamie Lokier <jamie@shareable.org> wrote:
>
>I meant: the trampoline _stack_ lives in the TSS.
>
>There is no trampoline _code_.

Ahh, ok. That sounds quite doable, and all my complaints go away.

It still leaves the debug exception and NMI issue.

The debug exception case is easy to trigger: use gdb to single-step
through the user-lebel fast system call code, and you _will_ get a debug
exception on the very first kernel instruction (which is also the one
that doesn't have a valid stack).

So anybody want to actually try to implement this?

Linus