* Todd Poynor <[EMAIL PROTECTED]> wrote:

> +static int
> +powerop_centrino_get_point(struct powerop_point *point)
> +{
> +     unsigned l, h;
> +     unsigned cpu_freq;
> +
> +     rdmsr(MSR_IA32_PERF_STATUS, l, h);
> +     if (unlikely((cpu_freq = ((l >> 8) & 0xff) * 100) == 0)) {
> +             /*
> +              * On some CPUs, we can see transient MSR values (which are
> +              * not present in _PSS), while CPU is doing some automatic
> +              * P-state transition (like TM2). Get the last freq set 
> +              * in PERF_CTL.
> +              */
> +             rdmsr(MSR_IA32_PERF_CTL, l, h);
> +             cpu_freq = ((l >> 8) & 0xff) * 100;
> +     }
> +
> +     point->param[POWEROP_CPU + smp_processor_id()] = cpu_freq;
> +     point->param[POWEROP_V + smp_processor_id()] = ((l & 0xff) * 16) + 700;
> +     return 0;
> +}

doesnt seem to be SMP-safe, nor PREEMPT-safe. You probably want to do 
the locking in the highlevel functions.

        Ingo
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