Re: [patch 1/2] i386: use asm() like the other atomic operations already do.

Herbert Xu wrote:

Andi Kleen <[email protected]> wrote:

My config with march=pentium-m and gcc (GCC) 4.1.2 (Gentoo 4.1.2):
  text    data     bss     dec     hex filename
3434150  249176  176128 3859454  3ae3fe atomic_normal/vmlinux
3435308  249176  176128 3860612  3ae884 atomic_inlineasm/vmlinux

What is the difference between atomic_normal and atomic_inlineasm?

The inline asm stops certain optimisations from occuring.

I'm still unconvinced why we need this because nobody has
brought up any examples of kernel code that legitimately
need this.

There's plenty of kernel code that *wants* this though. If we can reduce the need for register-clobbering barriers, shrink our binaries, shrink our code, improve performance, and avoid heisenbugs, I think it's a win, whether or not we *need* it.

	-- Chris
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