Re: PROBLEM: no cpu MHz in /proc/cpuinfo on 2.6.25.4-rt6

[Mark Hounschell]

Arjan van de Ven wrote:
> On Wed, 11 Jun 2008 16:37:38 -0400
> Mark Hounschell <markh@xxxxxxxxxx> wrote:
> 
>>> Mark 
>>>
>> Ok, what would one use besides the tsc to take a fast high-res time
>> stamp in a kernel module that could also be used in user land (same
>> time source) to for instance calculate  the the time between an event
>> in the kernel to an event in user land?
>>
>> do_gettimeofday / gettimeofday are not really acceptable.
> 
> 
> btw you also changed the problem from "what is the cpu frequency" to
> "how usable is rdtsc for time". My entire point was that these weren't
> related...
> 
> 

If they are not the same how do you know at what rate the tsc is counting.

But back to "how usable is rdtsc for time", is there a

clock_gettime(CLOCK_MONOTONIC, &time) equivalent that can be used in the kernel?

Mark
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