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

From: Gautham R Shenoy <[email-masked]>
Date: Mon, 24 Feb 2020 10:45:35 +0530

On Fri, Feb 21, 2020 at 10:55:07AM -0600, Nathan Lynch wrote:
> "Gautham R. Shenoy" <[email-masked]> 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 <[email-masked]>
> > +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 <[email-masked]>
> > +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 <[email-masked]>
> > +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 <[email-masked]>
> > +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