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Subject[PATCH V8 12/14] rtla: Add rtla timerlat documentation
Man page for rtla timerlat tool.

Cc: Steven Rostedt <>
Cc: Ingo Molnar <>
Cc: Tom Zanussi <>
Cc: Masami Hiramatsu <>
Cc: Juri Lelli <>
Cc: Clark Williams <>
Cc: John Kacur <>
Cc: Peter Zijlstra <>
Cc: Thomas Gleixner <>
Cc: Sebastian Andrzej Siewior <>
Cc: Daniel Bristot de Oliveira <>
Signed-off-by: Daniel Bristot de Oliveira <>
.../rtla/common_timerlat_description.rst | 10 ++++
Documentation/tools/rtla/rtla-timerlat.rst | 57 +++++++++++++++++++
2 files changed, 67 insertions(+)
create mode 100644 Documentation/tools/rtla/common_timerlat_description.rst
create mode 100644 Documentation/tools/rtla/rtla-timerlat.rst

diff --git a/Documentation/tools/rtla/common_timerlat_description.rst b/Documentation/tools/rtla/common_timerlat_description.rst
new file mode 100644
index 000000000000..321201cb8597
--- /dev/null
+++ b/Documentation/tools/rtla/common_timerlat_description.rst
@@ -0,0 +1,10 @@
+The **rtla timerlat** tool is an interface for the *timerlat* tracer. The
+*timerlat* tracer dispatches a kernel thread per-cpu. These threads
+set a periodic timer to wake themselves up and go back to sleep. After
+the wakeup, they collect and generate useful information for the
+debugging of operating system timer latency.
+The *timerlat* tracer outputs information in two ways. It periodically
+prints the timer latency at the timer *IRQ* handler and the *Thread*
+handler. It also enable the trace of the most relevant information via
+**osnoise:** tracepoints.
diff --git a/Documentation/tools/rtla/rtla-timerlat.rst b/Documentation/tools/rtla/rtla-timerlat.rst
new file mode 100644
index 000000000000..44a49e6f302b
--- /dev/null
+++ b/Documentation/tools/rtla/rtla-timerlat.rst
@@ -0,0 +1,57 @@
+Measures the operating system timer latency
+:Manual section: 1
+**rtla timerlat** [*MODE*] ...
+.. include:: common_timerlat_description.rst
+The *timerlat* tracer outputs information in two ways. It periodically
+prints the timer latency at the timer *IRQ* handler and the *Thread* handler.
+It also provides information for each noise via the **osnoise:** tracepoints.
+The **rtla timerlat top** mode displays a summary of the periodic output
+from the *timerlat* tracer. The **rtla hist hist** mode displays a histogram
+of each tracer event occurrence. For further details, please refer to the
+respective man page.
+ Prints the summary from *timerlat* tracer.
+ Prints a histogram of timerlat samples.
+If no *MODE* is given, the top mode is called, passing the arguments.
+**-h**, **--help**
+ Display the help text.
+For other options, see the man page for the corresponding mode.
+**rtla-timerlat-top**\(1), **rtla-timerlat-hist**\(1)
+*timerlat* tracer documentation: <>
+Written by Daniel Bristot de Oliveira <>
+.. include:: common_appendix.rst
 \ /
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