Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names

From: Rusty Russell
Date: Sat Aug 05 2006 - 23:50:38 EST

On Sun, 2006-08-06 at 05:16 +0200, Andi Kleen wrote:
> > Please reconsider. This isn't about being pretty, it's about not
> > having hidden side-effects,
> I wouldn't call it hidden, it's well defined in the architecture.

Sorry Andi, I'm not talking about the asm, which is fine. I'm talking
about the function-style macro which alters its arguments directly.
It's very bad form.

int a, b;
rdtsc(a, b);

> > and having typechecking.
> The existing code will already reject any non integer and I don't
> see a particular need to be more strict than that.


u64 c;
int a,b;

rdtsc(&a, &b);

These macros are badly named and don't check for bad usage. Sure, less
than 1% of uses is wrong at the moment, but I'm volunteering to fix them
because I think it sets a bad example and sets us up for more bugs.

I feel fairly strongly about this, but I'll drop the x86_64 changes.

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