Debugging Linux Kernel using ftrace Part 2 - Function Tracer

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To enable function tracer, echo "function" to current_tracer file.

$ echo "function" > current_tracer
$ cat current_tracer

To see the kernel trace, cat "trace" file


You can see from the cat output:
  • First line specifies the tracer installed, in our case "function"
  • Next each line prints the following information:
    • Process Name
    • PID
    • CPU that the trace executed on
    • Timestamp in seconds with the decimal places to microseconds. This timestamp is time since boot
    • Function being traced
    • Parent that call the function

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