Re: [patch] __volatile__ needed in get_cycles()?

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>On Tue, 30 Mar 1999, Ingo Molnar wrote:
>
>>to have 'exact' get_cycles() we need both the compiler-level barrier, and
>>both a pre- and post- rdtsc bus-level barrier, because both preceding and
>
>Are you really sure the post- rdtsc is needed? Sure theorically is needed,
>but maybe the CPU isn't so smart as theory.

My guess was right, Intel never uses the post- cpuid. And Intel _always_
uses cpuid _before_ rdtsc.

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