Re: [PATCH v2 5/5] Documentation: Document sysfs interfaces purr, spurr, idle_purr, idle_spurr

From: Gautham R Shenoy
Date: Mon Feb 24 2020 - 00:15:50 EST


On Fri, Feb 21, 2020 at 10:55:07AM -0600, Nathan Lynch wrote:
> "Gautham R. Shenoy" <ego@xxxxxxxxxxxxxxxxxx> writes:
> > diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
> > index 2e0e3b4..799dc737a 100644
> > --- a/Documentation/ABI/testing/sysfs-devices-system-cpu
> > +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
> > @@ -580,3 +580,42 @@ Description: Secure Virtual Machine
> > If 1, it means the system is using the Protected Execution
> > Facility in POWER9 and newer processors. i.e., it is a Secure
> > Virtual Machine.
> > +
> > +What: /sys/devices/system/cpu/cpuX/purr
> > +Date: Apr 2005
> > +Contact: Linux for PowerPC mailing list <linuxppc-dev@xxxxxxxxxx>
> > +Description: PURR ticks for this CPU since the system boot.
> > +
> > + The Processor Utilization Resources Register (PURR) is
> > + a 64-bit counter which provides an estimate of the
> > + resources used by the CPU thread. The contents of this
> > + register increases monotonically. This sysfs interface
> > + exposes the number of PURR ticks for cpuX.
> > +
> > +What: /sys/devices/system/cpu/cpuX/spurr
> > +Date: Dec 2006
> > +Contact: Linux for PowerPC mailing list <linuxppc-dev@xxxxxxxxxx>
> > +Description: SPURR ticks for this CPU since the system boot.
> > +
> > + The Scaled Processor Utilization Resources Register
> > + (SPURR) is a 64-bit counter that provides a frequency
> > + invariant estimate of the resources used by the CPU
> > + thread. The contents of this register increases
> > + monotonically. This sysfs interface exposes the number
> > + of SPURR ticks for cpuX.
> > +
> > +What: /sys/devices/system/cpu/cpuX/idle_purr
> > +Date: Nov 2019
> > +Contact: Linux for PowerPC mailing list <linuxppc-dev@xxxxxxxxxx>
> > +Description: PURR ticks for cpuX when it was idle.
> > +
> > + This sysfs interface exposes the number of PURR ticks
> > + for cpuX when it was idle.
> > +
> > +What: /sys/devices/system/cpu/cpuX/spurr
>
> Copy-paste error? This should be:

Yes, this should have been idle_spurr. Will fix it in the next
version.

>
> /sys/devices/system/cpu/cpuX/idle_spurr
>
> > +Date: Nov 2019
>
> And I suppose Nov 2019 is no longer accurate.

My bad. I will resend this with the updated date.


>
>
> > +Contact: Linux for PowerPC mailing list <linuxppc-dev@xxxxxxxxxx>
> > +Description: SPURR ticks for cpuX when it was idle.
> > +
> > + This sysfs interface exposes the number of SPURR ticks
> > + for cpuX when it was idle.
> > --
> > 1.9.4