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authorChangbin Du <changbin.du@intel.com>2018-02-17 13:39:44 +0800
committerJonathan Corbet <corbet@lwn.net>2018-03-07 10:25:59 -0700
commit47e073d2adcc73f4ad275f17af440d72ba652c2c (patch)
treea2217328d90daf2ee684a5d1e438f4b565754ab6 /Documentation/trace
parent3cdd868ec6fd24b103e0c7a435a99f5bd75ba6d9 (diff)
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trace doc: convert trace/events-power.txt to rst format
This converts the plain text documentation to reStructuredText format and add it into Sphinx TOC tree. No essential content change. Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/trace')
-rw-r--r--Documentation/trace/events-power.rst (renamed from Documentation/trace/events-power.txt)52
-rw-r--r--Documentation/trace/index.rst1
2 files changed, 31 insertions, 22 deletions
diff --git a/Documentation/trace/events-power.txt b/Documentation/trace/events-power.rst
index 21d514ced212..a77daca75e30 100644
--- a/Documentation/trace/events-power.txt
+++ b/Documentation/trace/events-power.rst
@@ -1,13 +1,14 @@
-
- Subsystem Trace Points: power
+=============================
+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
+ - Power state switch which reports events related to suspend (S-states),
+ cpuidle (C-states) and cpufreq (P-states)
+ - System clock related changes
+ - Power domains related changes and transitions
This document describes what each of the tracepoints is and why they
might be useful.
@@ -22,14 +23,16 @@ Cf. include/trace/events/power.h for the events definitions.
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"
+ 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"
+ machine_suspend "state=%lu"
Note: the value of '-1' or '4294967295' for state means an exit from the current state,
@@ -45,10 +48,11 @@ correctly draw the states diagrams and to calculate accurate statistics etc.
================
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"
+ 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
@@ -57,8 +61,9 @@ 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"
+ 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.
@@ -67,28 +72,31 @@ The second parameter is the power domain target state.
================
The PM QoS events are used for QoS add/update/remove request and for
target/flags update.
+::
-pm_qos_add_request "pm_qos_class=%s value=%d"
-pm_qos_update_request "pm_qos_class=%s value=%d"
-pm_qos_remove_request "pm_qos_class=%s value=%d"
-pm_qos_update_request_timeout "pm_qos_class=%s value=%d, timeout_us=%ld"
+ pm_qos_add_request "pm_qos_class=%s value=%d"
+ pm_qos_update_request "pm_qos_class=%s value=%d"
+ pm_qos_remove_request "pm_qos_class=%s value=%d"
+ pm_qos_update_request_timeout "pm_qos_class=%s value=%d, timeout_us=%ld"
The first parameter gives the QoS class name (e.g. "CPU_DMA_LATENCY").
The second parameter is value to be added/updated/removed.
The third parameter is timeout value in usec.
+::
-pm_qos_update_target "action=%s prev_value=%d curr_value=%d"
-pm_qos_update_flags "action=%s prev_value=0x%x curr_value=0x%x"
+ pm_qos_update_target "action=%s prev_value=%d curr_value=%d"
+ pm_qos_update_flags "action=%s prev_value=0x%x curr_value=0x%x"
The first parameter gives the QoS action name (e.g. "ADD_REQ").
The second parameter is the previous QoS value.
The third parameter is the current QoS value to update.
And, there are also events used for device PM QoS add/update/remove request.
+::
-dev_pm_qos_add_request "device=%s type=%s new_value=%d"
-dev_pm_qos_update_request "device=%s type=%s new_value=%d"
-dev_pm_qos_remove_request "device=%s type=%s new_value=%d"
+ dev_pm_qos_add_request "device=%s type=%s new_value=%d"
+ dev_pm_qos_update_request "device=%s type=%s new_value=%d"
+ dev_pm_qos_remove_request "device=%s type=%s new_value=%d"
The first parameter gives the device name which tries to add/update/remove
QoS requests.
diff --git a/Documentation/trace/index.rst b/Documentation/trace/index.rst
index 95586aaa9a5f..309c9c5b85a0 100644
--- a/Documentation/trace/index.rst
+++ b/Documentation/trace/index.rst
@@ -14,3 +14,4 @@ Linux Tracing Technologies
tracepoints
events
events-kmem
+ events-power