apfs/linux-apfs
0
0
Fork 0
mirror of https://github.com/linux-apfs/linux-apfs.git synced 2026-05-01 15:00:59 -07:00
Code Issues Packages Projects Releases Wiki Activity

cpuidle: Add Documentation

Browse Source 
Documentation for cpuidle infrastructure. (resend)

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Venkatesh Pallipadi
2008-02-14 00:16:13 -05:00
committed by Len Brown
parent 4fcb2fcd4d
commit fe8e288a63
5 changed files with 164 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Documentation/cpuidle/sysfs.txt
+79
View File
@@ -0,0 +1,79 @@
Supporting multiple CPU idle levels in kernel
cpuidle sysfs
System global cpuidle related information and tunables are under
/sys/devices/system/cpu/cpuidle
The current interfaces in this directory has self-explanatory names:
* current_driver
* current_governor_ro
With cpuidle_sysfs_switch boot option (meant for developer testing)
following objects are visible instead.
* current_driver
* available_governors
* current_governor
In this case users can switch the governor at run time by writing
to current_governor.
Per logical CPU specific cpuidle information are under
/sys/devices/system/cpu/cpuX/cpuidle
for each online cpu X
--------------------------------------------------------------------------------
# ls -lR /sys/devices/system/cpu/cpu0/cpuidle/
/sys/devices/system/cpu/cpu0/cpuidle/:
total 0
drwxr-xr-x 2 root root 0 Feb 8 10:42 state0
drwxr-xr-x 2 root root 0 Feb 8 10:42 state1
drwxr-xr-x 2 root root 0 Feb 8 10:42 state2
drwxr-xr-x 2 root root 0 Feb 8 10:42 state3
/sys/devices/system/cpu/cpu0/cpuidle/state0:
total 0
-r--r--r-- 1 root root 4096 Feb 8 10:42 desc
-r--r--r-- 1 root root 4096 Feb 8 10:42 latency
-r--r--r-- 1 root root 4096 Feb 8 10:42 name
-r--r--r-- 1 root root 4096 Feb 8 10:42 power
-r--r--r-- 1 root root 4096 Feb 8 10:42 time
-r--r--r-- 1 root root 4096 Feb 8 10:42 usage
/sys/devices/system/cpu/cpu0/cpuidle/state1:
total 0
-r--r--r-- 1 root root 4096 Feb 8 10:42 desc
-r--r--r-- 1 root root 4096 Feb 8 10:42 latency
-r--r--r-- 1 root root 4096 Feb 8 10:42 name
-r--r--r-- 1 root root 4096 Feb 8 10:42 power
-r--r--r-- 1 root root 4096 Feb 8 10:42 time
-r--r--r-- 1 root root 4096 Feb 8 10:42 usage
/sys/devices/system/cpu/cpu0/cpuidle/state2:
total 0
-r--r--r-- 1 root root 4096 Feb 8 10:42 desc
-r--r--r-- 1 root root 4096 Feb 8 10:42 latency
-r--r--r-- 1 root root 4096 Feb 8 10:42 name
-r--r--r-- 1 root root 4096 Feb 8 10:42 power
-r--r--r-- 1 root root 4096 Feb 8 10:42 time
-r--r--r-- 1 root root 4096 Feb 8 10:42 usage
/sys/devices/system/cpu/cpu0/cpuidle/state3:
total 0
-r--r--r-- 1 root root 4096 Feb 8 10:42 desc
-r--r--r-- 1 root root 4096 Feb 8 10:42 latency
-r--r--r-- 1 root root 4096 Feb 8 10:42 name
-r--r--r-- 1 root root 4096 Feb 8 10:42 power
-r--r--r-- 1 root root 4096 Feb 8 10:42 time
-r--r--r-- 1 root root 4096 Feb 8 10:42 usage
--------------------------------------------------------------------------------
* desc : Small description about the idle state (string)
* latency : Latency to exit out of this idle state (in microseconds)
* name : Name of the idle state (string)
* power : Power consumed while in this idle state (in milliwatts)
* time : Total time spent in this idle state (in microseconds)
* usage : Number of times this state was entered (count)