Commit b020771a authored by Jinzhou Su's avatar Jinzhou Su Committed by Rafael J. Wysocki
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Documentation: amd-pstate: add tracer tool introduction 



Add amd pstate tracer tool introduction

Signed-off-by: default avatarJinzhou Su <Jinzhou.Su@amd.com>
Reviewed-by: default avatarHuang Rui <ray.huang@amd.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 5e32adcc

Documentation/admin-guide/pm/amd-pstate.rst

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Original line number Diff line number Diff line
@@ -369,6 +369,32 @@ governor (for the policies it is attached to), or by the ``CPUFreq`` core (for t 
policies with other scaling governors).





Tracer Tool

-------------



``amd_pstate_tracer.py`` can record and parse ``amd-pstate`` trace log, then

generate performance plots. This utility can be used to debug and tune the

performance of ``amd-pstate`` driver. The tracer tool needs to import intel

pstate tracer.



Tracer tool located in ``linux/tools/power/x86/amd_pstate_tracer``. It can be

used in two ways. If trace file is available, then directly parse the file

with command ::



 ./amd_pstate_trace.py [-c cpus] -t <trace_file> -n <test_name>



Or generate trace file with root privilege, then parse and plot with command ::



 sudo ./amd_pstate_trace.py [-c cpus] -n <test_name> -i <interval> [-m kbytes]



The test result can be found in ``results/test_name``. Following is the example

about part of the output. ::



 common_cpu  common_secs  common_usecs  min_perf  des_perf  max_perf  freq    mperf   apef    tsc       load   duration_ms  sample_num  elapsed_time  common_comm

 CPU_005     712          116384        39        49        166       0.7565  9645075 2214891 38431470  25.1   11.646       469         2.496         kworker/5:0-40

 CPU_006     712          116408        39        49        166       0.6769  8950227 1839034 37192089  24.06  11.272       470         2.496         kworker/6:0-1264





Reference

===========