Collect real process and processor utilization values when virtualization is enabled.

Olof Johansson olof at
Wed Jan 12 15:06:28 EST 2005

Hi Manish,

On Tue, Jan 11, 2005 at 07:08:13PM -0600, Manish Ahuja wrote:

> The patch also calculates how much real cpu time each process uses and 
> stores this value in a ppc64 specific struct. 

I was going to ask a couple of questions about this and noticed Andrew
Morton's reply pointing at cputime. That answered most of them (how
other archs might be doing it).

> The value is needed by CKRM to do further calculations.

How will CKRM use this? Does it have architecture-specific code to
dig this out of the thread_struct again? Could they use the cputime
interface if we hooked into that instead?

Finally: There's two ways to read PURR on our platform: One is to read
the SPR value, the other to get it from the hypervisor via the H_PURR
call. Do they measure the same thing and stay consistent?


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