From aa5eee355b466cb33f97f79bed9740a472c4ab73 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 29 Nov 2018 22:22:04 +0100 Subject: Documentation: admin-guide: PM: Add cpuidle document Important information is missing from user/admin cpuidle documentation available today, so add a new user/admin document for cpuidle containing current and comprehensive information to admin-guide and drop the old .txt documents it is replacing. Signed-off-by: Rafael J. Wysocki Reviewed-by: Viresh Kumar Reviewed-by: Ulf Hansson --- Documentation/cpuidle/core.txt | 23 ---------- Documentation/cpuidle/sysfs.txt | 98 ----------------------------------------- 2 files changed, 121 deletions(-) delete mode 100644 Documentation/cpuidle/core.txt delete mode 100644 Documentation/cpuidle/sysfs.txt (limited to 'Documentation/cpuidle') diff --git a/Documentation/cpuidle/core.txt b/Documentation/cpuidle/core.txt deleted file mode 100644 index 63ecc5dc9d8a..000000000000 --- a/Documentation/cpuidle/core.txt +++ /dev/null @@ -1,23 +0,0 @@ - - Supporting multiple CPU idle levels in kernel - - cpuidle - -General Information: - -Various CPUs today support multiple idle levels that are differentiated -by varying exit latencies and power consumption during idle. -cpuidle is a generic in-kernel infrastructure that separates -idle policy (governor) from idle mechanism (driver) and provides a -standardized infrastructure to support independent development of -governors and drivers. - -cpuidle resides under drivers/cpuidle. - -Boot options: -"cpuidle_sysfs_switch" -enables current_governor interface in /sys/devices/system/cpu/cpuidle/, -which can be used to switch governors at run time. This boot option -is meant for developer testing only. In normal usage, kernel picks the -best governor based on governor ratings. -SEE ALSO: sysfs.txt in this directory. diff --git a/Documentation/cpuidle/sysfs.txt b/Documentation/cpuidle/sysfs.txt deleted file mode 100644 index d1587f434e7b..000000000000 --- a/Documentation/cpuidle/sysfs.txt +++ /dev/null @@ -1,98 +0,0 @@ - - - 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 --rw-r--r-- 1 root root 4096 Feb 8 10:42 disable --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 residency --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 --rw-r--r-- 1 root root 4096 Feb 8 10:42 disable --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 residency --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 --rw-r--r-- 1 root root 4096 Feb 8 10:42 disable --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 residency --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 --rw-r--r-- 1 root root 4096 Feb 8 10:42 disable --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 residency --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) -* disable : Option to disable this idle state (bool) -> see note below -* latency : Latency to exit out of this idle state (in microseconds) -* residency : Time after which a state becomes more effecient than any - shallower 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) - -Note: -The behavior and the effect of the disable variable depends on the -implementation of a particular governor. In the ladder governor, for -example, it is not coherent, i.e. if one is disabling a light state, -then all deeper states are disabled as well, but the disable variable -does not reflect it. Likewise, if one enables a deep state but a lighter -state still is disabled, then this has no effect. -- cgit v1.2.3