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    SubjectRe: [patch 1/2] i386: use asm() like the other atomic operations already do.
    Herbert Xu wrote:
    > Andi Kleen <ak@suse.de> 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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