Commit bde752c3 authored by Gautham R. Shenoy's avatar Gautham R. Shenoy Committed by Michael Ellerman
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Documentation: Document sysfs interfaces purr, spurr, idle_purr, idle_spurr 



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: default avatarGautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1586249263-14048-6-git-send-email-ego@linux.vnet.ibm.com
parent 6909f179

Documentation/ABI/testing/sysfs-devices-system-cpu

+39 −0
Original line number Diff line number Diff line
@@ -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@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@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:		Apr 2020

Contact:	Linux for PowerPC mailing list <linuxppc-dev@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:		Apr 2020

Contact:	Linux for PowerPC mailing list <linuxppc-dev@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.