linux/Documentation/trace/events-msr.rst

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MSR Trace Events
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The x86 kernel supports tracing most MSR (Model Specific Register) accesses.
To see the definition of the MSRs on Intel systems please see the SDM
at https://www.intel.com/sdm (Volume 3)

Available trace points:

/sys/kernel/debug/tracing/events/msr/

Trace MSR reads:

read_msr

  - msr: MSR number
  - val: Value written
  - failed: 1 if the access failed, otherwise 0


Trace MSR writes:

write_msr

  - msr: MSR number
  - val: Value written
  - failed: 1 if the access failed, otherwise 0


Trace RDPMC in kernel:

rdpmc

The trace data can be post processed with the postprocess/decode_msr.py script::

  cat /sys/kernel/debug/tracing/trace | decode_msr.py /usr/src/linux/include/asm/msr-index.h

to add symbolic MSR names.