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

Gautham R. Shenoy
2020-03-27T11:33:07Z

From: "Gautham R. Shenoy" <ego@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@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@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: Mar 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: Mar 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.
--
1.9.4