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-rw-r--r--Documentation/tools/rtla/common_timerlat_description.rst10
-rw-r--r--Documentation/tools/rtla/rtla-timerlat.rst57
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+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
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+================
+rtla-timerlat
+================
+-------------------------------------------
+Measures the operating system timer latency
+-------------------------------------------
+
+:Manual section: 1
+
+SYNOPSIS
+========
+**rtla timerlat** [*MODE*] ...
+
+DESCRIPTION
+===========
+
+.. 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.
+
+MODES
+=====
+**top**
+
+ Prints the summary from *timerlat* tracer.
+
+**hist**
+
+ Prints a histogram of timerlat samples.
+
+If no *MODE* is given, the top mode is called, passing the arguments.
+
+OPTIONS
+=======
+**-h**, **--help**
+
+ Display the help text.
+
+For other options, see the man page for the corresponding mode.
+
+SEE ALSO
+========
+**rtla-timerlat-top**\(1), **rtla-timerlat-hist**\(1)
+
+*timerlat* tracer documentation: <https://www.kernel.org/doc/html/latest/trace/timerlat-tracer.html>
+
+AUTHOR
+======
+Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst