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diff --git a/Documentation/trace/events-power.txt b/Documentation/trace/events-power.txt deleted file mode 100644 index cf794af2285..00000000000 --- a/Documentation/trace/events-power.txt +++ /dev/null @@ -1,90 +0,0 @@ - - Subsystem Trace Points: power - -The power tracing system captures events related to power transitions -within the kernel. Broadly speaking there are three major subheadings: - - o Power state switch which reports events related to suspend (S-states), - cpuidle (C-states) and cpufreq (P-states) - o System clock related changes - o Power domains related changes and transitions - -This document describes what each of the tracepoints is and why they -might be useful. - -Cf. include/trace/events/power.h for the events definitions. - -1. Power state switch events -============================ - -1.1 New trace API ------------------ - -A 'cpu' event class gathers the CPU-related events: cpuidle and -cpufreq. - -cpu_idle "state=%lu cpu_id=%lu" -cpu_frequency "state=%lu cpu_id=%lu" - -A suspend event is used to indicate the system going in and out of the -suspend mode: - -machine_suspend "state=%lu" - - -Note: the value of '-1' or '4294967295' for state means an exit from the current state, -i.e. trace_cpu_idle(4, smp_processor_id()) means that the system -enters the idle state 4, while trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id()) -means that the system exits the previous idle state. - -The event which has 'state=4294967295' in the trace is very important to the user -space tools which are using it to detect the end of the current state, and so to -correctly draw the states diagrams and to calculate accurate statistics etc. - -1.2 DEPRECATED trace API ------------------------- - -A new Kconfig option CONFIG_EVENT_POWER_TRACING_DEPRECATED with the default value of -'y' has been created. This allows the legacy trace power API to be used conjointly -with the new trace API. -The Kconfig option, the old trace API (in include/trace/events/power.h) and the -old trace points will disappear in a future release (namely 2.6.41). - -power_start "type=%lu state=%lu cpu_id=%lu" -power_frequency "type=%lu state=%lu cpu_id=%lu" -power_end "cpu_id=%lu" - -The 'type' parameter takes one of those macros: - . POWER_NONE = 0, - . POWER_CSTATE = 1, /* C-State */ - . POWER_PSTATE = 2, /* Frequency change or DVFS */ - -The 'state' parameter is set depending on the type: - . Target C-state for type=POWER_CSTATE, - . Target frequency for type=POWER_PSTATE, - -power_end is used to indicate the exit of a state, corresponding to the latest -power_start event. - -2. Clocks events -================ -The clock events are used for clock enable/disable and for -clock rate change. - -clock_enable "%s state=%lu cpu_id=%lu" -clock_disable "%s state=%lu cpu_id=%lu" -clock_set_rate "%s state=%lu cpu_id=%lu" - -The first parameter gives the clock name (e.g. "gpio1_iclk"). -The second parameter is '1' for enable, '0' for disable, the target -clock rate for set_rate. - -3. Power domains events -======================= -The power domain events are used for power domains transitions - -power_domain_target "%s state=%lu cpu_id=%lu" - -The first parameter gives the power domain name (e.g. "mpu_pwrdm"). -The second parameter is the power domain target state. - |