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

From: Nathan Lynch <[email-masked]>
Date: Fri, 21 Feb 2020 10:55:07 -0600

"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:

                        /sys/devices/system/cpu/cpuX/idle_spurr

> +Date:		Nov 2019

And I suppose Nov 2019 is no longer accurate.

> +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