[PATCH v4 5/6] Documentation: Document sysfs interfaces purr, spurr, idle_purr, idle_spurr

[Naveen N. Rao]

Gautham R. Shenoy wrote:
> From: "Gautham R. Shenoy" <ego at linux.vnet.ibm.com>
> 
> Add documentation for the following sysfs interfaces:
> /sys/devices/system/cpu/cpuX/purr
> /sys/devices/system/cpu/cpuX/spurr
> /sys/devices/system/cpu/cpuX/idle_purr
> /sys/devices/system/cpu/cpuX/idle_spurr
> 
> Signed-off-by: Gautham R. Shenoy <ego at linux.vnet.ibm.com>
> ---
>  Documentation/ABI/testing/sysfs-devices-system-cpu | 39 ++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
> index 2e0e3b4..bc07677 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 at ozlabs.org>
> +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 at ozlabs.org>
> +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:		Mar 2020
> +Contact:	Linux for PowerPC mailing list <linuxppc-dev at ozlabs.org>
> +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/idle_spurr
> +Date:		Mar 2020
> +Contact:	Linux for PowerPC mailing list <linuxppc-dev at ozlabs.org>
> +Description:	SPURR ticks for cpuX when it was idle.
> +
> +		This sysfs interface exposes the number of SPURR ticks
> +		for cpuX when it was idle.

Apart from the minor comment on patches 2 and 3, from the sysfs 
interface standpoint, for patches 1 to 5:
Acked-by: Naveen N. Rao <naveen.n.rao at linux.vnet.ibm.com>

- Naveen