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realtime:documentation:howto:debugging:cyclictest:debugging [2018/07/23 14:10]
ebugden Improve phrasing
realtime:documentation:howto:debugging:cyclictest:debugging [2018/08/06 12:26]
ebugden Move explanation in information box
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 ====== Cyclictest - Latency debugging with tracing ====== ====== Cyclictest - Latency debugging with tracing ======
  
-Tracing is useful when trying to determine the cause of a latency because it can reveal relevant details about execution. There are several options in Cyclictest that can be used to produce traces via Ftrace. These traces can then be consulted via tracefs.+Tracing is useful when trying to determine the cause of a latency because it can reveal relevant details about execution. There are several options in Cyclictest that can be used to produce traces via Ftrace.
  
 ===== Break Trace Option ===== ===== Break Trace Option =====
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 <WRAP center round info 60%> <WRAP center round info 60%>
-Ftrace might not behave the same way after using the break trace option. ​+Ftrace might not behave the same way after using the break trace option. When the break trace option is used, Cyclictest changes some Ftrace options to get the desired trace format, such as specifying print-parent and latency-format. The Ftrace options that were set before are not restored after Cyclictest runs.
 </​WRAP>​ </​WRAP>​
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-When the break trace option is used, Cyclictest changes some Ftrace options to get the desired trace format, such as specifying print-parent and latency-format. The Ftrace options that were set before are not restored after Cyclictest runs. 
  
 ===== Selecting Instrumentation ===== ===== Selecting Instrumentation =====