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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 13:17:26 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 13:17:26 -0500
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 01ece1b9213e..992cda68fa63 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
1579 1579
1580 nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels 1580 nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
1581 Format: [panic,][num] 1581 Format: [panic,][num]
1582 Valid num: 0,1,2 1582 Valid num: 0
1583 0 - turn nmi_watchdog off 1583 0 - turn nmi_watchdog off
1584 1 - use the IO-APIC timer for the NMI watchdog
1585 2 - use the local APIC for the NMI watchdog using
1586 a performance counter. Note: This will use one
1587 performance counter and the local APIC's performance
1588 vector.
1589 When panic is specified, panic when an NMI watchdog 1584 When panic is specified, panic when an NMI watchdog
1590 timeout occurs. 1585 timeout occurs.
1591 This is useful when you use a panic=... timeout and 1586 This is useful when you use a panic=... timeout and
1592 need the box quickly up again. 1587 need the box quickly up again.
1593 Instead of 1 and 2 it is possible to use the following
1594 symbolic names: lapic and ioapic
1595 Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
1596 1588
1597 netpoll.carrier_timeout= 1589 netpoll.carrier_timeout=
1598 [NET] Specifies amount of time (in seconds) that 1590 [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 000000000000..96d87b67fe37
--- /dev/null
+++ b/Documentation/trace/events-power.txt
@@ -0,0 +1,90 @@
1
2 Subsystem Trace Points: power
3
4The power tracing system captures events related to power transitions
5within the kernel. Broadly speaking there are three major subheadings:
6
7 o Power state switch which reports events related to suspend (S-states),
8 cpuidle (C-states) and cpufreq (P-states)
9 o System clock related changes
10 o Power domains related changes and transitions
11
12This document describes what each of the tracepoints is and why they
13might be useful.
14
15Cf. include/trace/events/power.h for the events definitions.
16
171. Power state switch events
18============================
19
201.1 New trace API
21-----------------
22
23A 'cpu' event class gathers the CPU-related events: cpuidle and
24cpufreq.
25
26cpu_idle "state=%lu cpu_id=%lu"
27cpu_frequency "state=%lu cpu_id=%lu"
28
29A suspend event is used to indicate the system going in and out of the
30suspend mode:
31
32machine_suspend "state=%lu"
33
34
35Note: the value of '-1' or '4294967295' for state means an exit from the current state,
36i.e. trace_cpu_idle(4, smp_processor_id()) means that the system
37enters the idle state 4, while trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id())
38means that the system exits the previous idle state.
39
40The event which has 'state=4294967295' in the trace is very important to the user
41space tools which are using it to detect the end of the current state, and so to
42correctly draw the states diagrams and to calculate accurate statistics etc.
43
441.2 DEPRECATED trace API
45------------------------
46
47A new Kconfig option CONFIG_EVENT_POWER_TRACING_DEPRECATED with the default value of
48'y' has been created. This allows the legacy trace power API to be used conjointly
49with the new trace API.
50The Kconfig option, the old trace API (in include/trace/events/power.h) and the
51old trace points will disappear in a future release (namely 2.6.41).
52
53power_start "type=%lu state=%lu cpu_id=%lu"
54power_frequency "type=%lu state=%lu cpu_id=%lu"
55power_end "cpu_id=%lu"
56
57The 'type' parameter takes one of those macros:
58 . POWER_NONE = 0,
59 . POWER_CSTATE = 1, /* C-State */
60 . POWER_PSTATE = 2, /* Fequency change or DVFS */
61
62The 'state' parameter is set depending on the type:
63 . Target C-state for type=POWER_CSTATE,
64 . Target frequency for type=POWER_PSTATE,
65
66power_end is used to indicate the exit of a state, corresponding to the latest
67power_start event.
68
692. Clocks events
70================
71The clock events are used for clock enable/disable and for
72clock rate change.
73
74clock_enable "%s state=%lu cpu_id=%lu"
75clock_disable "%s state=%lu cpu_id=%lu"
76clock_set_rate "%s state=%lu cpu_id=%lu"
77
78The first parameter gives the clock name (e.g. "gpio1_iclk").
79The second parameter is '1' for enable, '0' for disable, the target
80clock rate for set_rate.
81
823. Power domains events
83=======================
84The power domain events are used for power domains transitions
85
86power_domain_target "%s state=%lu cpu_id=%lu"
87
88The first parameter gives the power domain name (e.g. "mpu_pwrdm").
89The second parameter is the power domain target state.
90