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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 10:17:26 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 10:17:26 -0800
commit28d9bfc37c861aa9c8386dff1ac7e9a10e5c5162 (patch)
tree85bcc2db18ff20e380a40aba375e70d14c2671b4 /Documentation
parentf3b0cfa9b017a9d4686c9b14b908a1685f97a077 (diff)
parent4b95f135f606c87e4056b6d7fd3c5781c818858b (diff)
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (146 commits) tools, perf: Documentation for the power events API perf: Add calls to suspend trace point perf script: Make some lists static perf script: Use the default lost event handler perf session: Warn about errors when processing pipe events too perf tools: Fix perf_event.h header usage perf test: Clarify some error reports in the open syscall test x86, NMI: Add touch_nmi_watchdog to io_check_error delay x86: Avoid calling arch_trigger_all_cpu_backtrace() at the same time x86: Only call smp_processor_id in non-preempt cases perf timechart: Adjust perf timechart to the new power events perf: Clean up power events by introducing new, more generic ones perf: Do not export power_frequency, but power_start event perf test: Add test for counting open syscalls perf evsel: Auto allocate resources needed for some methods perf evsel: Use {cpu,thread}_map to shorten list of parameters perf tools: Refactor all_tids to hold nr and the map perf tools: Refactor cpumap to hold nr and the map perf evsel: Introduce per cpu and per thread open helpers perf evsel: Steal the counter reading routines from stat ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/kernel-parameters.txt10
-rw-r--r--Documentation/trace/events-power.txt90
2 files changed, 91 insertions, 9 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 01ece1b9213..992cda68fa6 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1579,20 +1579,12 @@ and is between 256 and 4096 characters. It is defined in the file
nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
Format: [panic,][num]
- Valid num: 0,1,2
+ Valid num: 0
0 - turn nmi_watchdog off
- 1 - use the IO-APIC timer for the NMI watchdog
- 2 - use the local APIC for the NMI watchdog using
- a performance counter. Note: This will use one
- performance counter and the local APIC's performance
- vector.
When panic is specified, panic when an NMI watchdog
timeout occurs.
This is useful when you use a panic=... timeout and
need the box quickly up again.
- Instead of 1 and 2 it is possible to use the following
- symbolic names: lapic and ioapic
- Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
netpoll.carrier_timeout=
[NET] Specifies amount of time (in seconds) that
diff --git a/Documentation/trace/events-power.txt b/Documentation/trace/events-power.txt
new file mode 100644
index 00000000000..96d87b67fe3
--- /dev/null
+++ b/Documentation/trace/events-power.txt
@@ -0,0 +1,90 @@
+
+ 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, /* Fequency 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.
+