[PATCH] tools/power/x86: Debug utility for intel_pstate driver

[Srinivas Pandruvada]

This utility can be used to debug and tune the performance of the
intel_pstate driver.
This utility can be used in two ways:
- If there is Linux trace file with pstate_sample events enabled, then
this utility can parse the trace file and generate performance plots.
- If user has not specified a trace file as input via command line
parameters, then this utility enables and collects trace data for a user
specified interval and generates performance plots.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
 .../x86/intel_pstate_tracer/intel_pstate_tracer.py | 287 +++++++++++++++++++++
 1 file changed, 287 insertions(+)
 create mode 100755 tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py

diff --git a/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py b/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py
new file mode 100755
index 0000000..00ed159
--- /dev/null
+++ b/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py
@@ -0,0 +1,287 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+""" This utility can be used to debug and tune the performance of the
+intel_pstate driver. This utility can be used in two ways:
+- If there is Linux trace file with pstate_sample events enabled, then
+this utility can parse the trace file and generate performance plots.
+- If user has not specified a trace file as input via command line parameters,
+then this utility enables and collects trace data for a user specified interval
+and generates performance plots.
+
+Prerequisites:
+    Python version 2.7.x
+    gnuplot 5.0 or higher
+    gnuplot-py 1.8
+    (Most of the distributions have these required packages)
+
+    HWP (Hardware P-States are disabled)
+    Kernel config for Linux trace is enabled
+
+    Usage:
+        If the trace file is available, then to simply parse and plot, use
+            sudo ./intel_pstate_tracer.py -t <trace_file>
+        To generate trace file, parse and plot, use
+            sudo ./intel_pstate_tracer.py -i <interval>
+    Output:
+        Creates a "data" folder in the current working directory and copies:
+        cpu*.dat           - Raw performance data
+        cpu_perf_busy*.png - Plots of P-States, Performance, busy
+	                     and io_busy
+        all_cpu_per.png    - Plot of P-State transition on each CPU
+
+"""
+from __future__ import print_function
+import os
+import time
+import re
+import sys
+import getopt
+import Gnuplot
+
+__author__ = "Srinivas Pandruvada"
+__copyright__ = " Copyright (c) 2017, Intel Corporation. "
+__license__ = "GPL version 2"
+
+
+MAX_CPUS = 256
+
+def plot_perf_busy(cpu_index):
+    """ Plot method to per cpu information """
+
+    file_name = 'cpu' + str(cpu_index) + '.dat'
+    if os.path.exists(file_name):
+
+        output_png = "cpu_perf_busy%d.png" % cpu_index
+        g_plot = Gnuplot.Gnuplot(persist=1)
+        g_plot('set yrange [0:40]')
+        g_plot('set y2range [0:100]')
+        g_plot('set y2tics 0, 10')
+        g_plot('set ytics nomirror')
+        g_plot('set xlabel "Samples"')
+        g_plot('set ylabel "P-State"')
+        g_plot('set y2label "Scaled Busy"')
+        g_plot('set term png size 1280, 720')
+        g_plot('set output "' + output_png + '"')
+
+        g_plot.plot(Gnuplot.File(file_name, using='1',
+                                 with_="lines linecolor 'green' axis x1y2",
+                                 title='performance'),
+                    Gnuplot.File(file_name,
+                                 using='2', with_="lines linecolor 'red' axis x1y2",
+                                 title='scaled-busy'),
+                    Gnuplot.File(file_name,
+                                 using='4',
+                                 with_="lines linecolor 'purple' axis x1y2",
+                                 title='io-busy'),
+                    Gnuplot.File(file_name, using='3',
+                                 with_="lines linecolor 'blue' axis x1y1",
+                                 title='P-State'))
+
+
+def plot_perf_cpu():
+    """ Plot all cpu information """
+
+    if os.path.exists('cpu.dat'):
+        output_png = 'all_cpu_perf.png'
+        g_plot = Gnuplot.Gnuplot(persist=1)
+        g_plot('set yrange [0:30]')
+        g_plot('set xlabel "Samples"')
+        g_plot('set ylabel "P-State"')
+        g_plot('set term png size 1280, 720')
+        g_plot('set output "' + output_png + '"')
+
+        plot_str = 'plot for [col=1:' + str(current_max_cpu + 1) \
+                              + "] 'cpu.dat' using 0:col with lines title columnheader"
+
+        g_plot.__call__(plot_str)
+
+def store_per_cpu_information(cup_index, perf, busy, pstate, io_boost_pct):
+    """ Store information for each CPU """
+
+    try:
+        f_handle = open('cpu' + cup_index + '.dat', 'a')
+        sep = "\t";
+        f_handle.write(sep.join((perf, busy, pstate, io_boost_pct)) + '\n');
+        f_handle.close()
+    except:
+        print('IO error cpu*.dat')
+        return
+
+    try:
+        f_handle = open('cpu.dat', 'a')
+        for index in range(0, int(cup_index)):
+            f_handle.write('0\t')
+
+        f_handle.write(pstate + '\t')
+        for index in range(int(cup_index) + 1, MAX_CPUS):
+            f_handle.write('0\t')
+        f_handle.write('\n')
+        f_handle.close()
+    except:
+        print('IO error cpu.dat')
+        return
+
+def cleanup_data_files():
+    """ clean up existing data files """
+
+    for index in range(0, MAX_CPUS):
+        filename = 'cpu' + str(index) + '.dat'
+        if os.path.exists(filename):
+            os.remove(filename)
+
+    if os.path.exists('cpu.dat'):
+        os.remove('cpu.dat')
+        f_handle = open('cpu.dat', 'a')
+        for index in range(0, MAX_CPUS):
+            f_handle.write('cpu' + str(index) + '\t')
+        f_handle.close()
+
+def clear_trace_file():
+    """ Clear trace file """
+    try:
+        f_handle = open('/sys/kernel/debug/tracing/trace', 'w')
+        f_handle.close()
+    except:
+        print('IO error clearing trace file ')
+        quit()
+
+def enable_trace():
+    """ Enable trace """
+    try:
+       open('/sys/kernel/debug/tracing/events/power/pstate_sample/enable'
+                 , 'w').write("1")
+    except:
+        print('IO error enabling trace ')
+        quit()
+
+def disable_trace():
+    """ Enable trace """
+    try:
+       open('/sys/kernel/debug/tracing/events/power/pstate_sample/enable'
+                 , 'w').write("0")
+    except:
+        print('IO error disabling trace ')
+        quit()
+
+def set_trace_buffer_size():
+    """ Set trace buffer size """
+    try:
+       open('/sys/kernel/debug/tracing/buffer_size_kb'
+                 , 'w').write("10240")
+    except:
+        print('IO error setting trace buffer size ')
+        quit()
+
+def read_and_plot_trace_data(filename):
+    """ Read trace data and call for plot """
+
+    global current_max_cpu
+    try:
+        data = open(filename, 'r').read()
+    except:
+        print('Error opening ', filename)
+        quit()
+
+    for line in data.splitlines():
+        search_obj = \
+            re.search(r'(^(.*?)\[)((\d+)[^\]])(.*?core_busy=)(\d+)(.*?scaled=)(\d+)(.*?from=)(\d+)(.*?to=)(\d+)(.*?mperf=)(\d+)(.*?aperf=)(\d+)(.*?tsc=)(\d+)(.*?freq=)(\d+)'
+                      , line)
+
+        if search_obj:
+            cpu = search_obj.group(3)
+            cpu_int = int(cpu)
+            cpu = str(cpu_int)
+
+            print('[\ncpu : ', cpu)
+
+            core_busy = search_obj.group(6)
+            print('core_busy : ', core_busy)
+
+            scaled = search_obj.group(8)
+            print('scaled : ', scaled)
+
+            _from = search_obj.group(10)
+            print('from : ', _from)
+
+            _to = search_obj.group(12)
+            print('to : ', _to)
+
+            mperf = search_obj.group(14)
+            print('mperf : ', mperf)
+
+            aperf = search_obj.group(16)
+            print('aperf : ', aperf)
+
+            tsc = search_obj.group(18)
+            print('tsc : ', tsc)
+
+            freq = search_obj.group(20)
+            print('freq : ', freq)
+
+            # Not all kernel version has io_boost field
+
+            io_boost = '0'
+            search_obj = re.search(r'.*?io_boost=(\d+)', line)
+            if search_obj:
+                print('io_boost : ', search_obj.group(1))
+
+            store_per_cpu_information(cpu, core_busy, scaled, _to, io_boost)
+
+            if int(cpu) > current_max_cpu:
+                current_max_cpu = int(cpu)
+
+interval = ""
+filename = ""
+valid = False
+
+try:
+    opts, args = getopt.getopt(sys.argv[1:],"ht:i:",["trace_file=","interval="])
+except getopt.GetoptError:
+    print('intel_pstate_tracer.py -t <trace_file>')
+    print('intel_pstate_tracer.py -i <interval>')
+    sys.exit(2)
+for opt, arg in opts:
+    if opt == '-h':
+        print('intel_pstate_tracer.py -t <trace_file>')
+        print('intel_pstate_tracer.py -i <interval>')
+        sys.exit()
+    elif opt in ("-t", "--trace_file"):
+        valid = True
+        filename = arg
+    elif opt in ("-i", "--interval"):
+        valid = True
+        interval = arg
+
+if not valid:
+        print('intel_pstate_tracer.py -t <trace_file>')
+        print('intel_pstate_tracer.py -i <interval>')
+        sys.exit()
+
+if not os.path.exists('data'):
+    os.mkdir('data')
+
+os.chdir('data')
+
+cleanup_data_files()
+
+if interval:
+    filename = "/sys/kernel/debug/tracing/trace"
+    clear_trace_file()
+    set_trace_buffer_size()
+    enable_trace()
+    print('Sleeping for ', interval, 'seconds')
+    time.sleep(int(interval))
+
+current_max_cpu = 0
+
+read_and_plot_trace_data(filename)
+
+if interval:
+    disable_trace()
+
+for cpu_no in range(0, current_max_cpu + 1):
+    plot_perf_busy(cpu_no)
+
+plot_perf_cpu()
+
+os.chdir('../')
-- 
2.7.4