text: #!/bin/bash
  #
  # This test runs on Intel x86 based hardware which support the intel_pstate
  # driver.  The test checks the frequency settings from the maximum turbo
  # state to the minimum supported frequency, in decrements of 100MHz.  The
  # test runs the aperf.c program to put load on each processor.
  #
  # The results are displayed in a table which indicate the "Target" state,
  # or the requested frequency in MHz, the Actual frequency, as read from
  # /proc/cpuinfo, the difference between the Target and Actual frequencies,
  # and the value of MSR 0x199 (MSR_IA32_PERF_CTL) which indicates what
  # pstate the cpu is in, and the value of
  # /sys/devices/system/cpu/intel_pstate/max_perf_pct X maximum turbo state
  #
  # Notes: In some cases several frequency values may be placed in the
  # /tmp/result.X files.  This is done on purpose in order to catch cases
  # where the pstate driver may not be working at all.  There is the case
  # where, for example, several "similar" frequencies are in the file:
  #
  #
  #/tmp/result.3100:1:cpu MHz              : 2899.980
  #/tmp/result.3100:2:cpu MHz              : 2900.000
  #/tmp/result.3100:3:msr 0x199: 0x1e00
  #/tmp/result.3100:4:max_perf_pct 94
  #
  # and the test will error out in those cases.  The result.X file can be checked
  # for consistency and modified to remove the extra MHz values.  The result.X
  # files can be re-evaluated by setting EVALUATE_ONLY to 1 below.
  
  EVALUATE_ONLY=0
  
  max_cpus=$(($(nproc)-1))
  
  # compile programs
  gcc aperf.c -Wall -D_GNU_SOURCE -o aperf  -lm
  [ $? -ne 0 ] && echo "Problem compiling aperf.c." && exit 1
  gcc -o msr msr.c -lm
  [ $? -ne 0 ] && echo "Problem compiling msr.c." && exit 1
  
  function run_test () {
  
  	file_ext=$1
  	for cpu in `seq 0 $max_cpus`
  	do
  		echo "launching aperf load on $cpu"
  		./aperf $cpu &
  	done
  
  	echo "sleeping for 5 seconds"
  	sleep 5
  	num_freqs=$(cat /proc/cpuinfo | grep MHz | sort -u | wc -l)
  	if [ $num_freqs -le 2 ]; then
  		cat /proc/cpuinfo | grep MHz | sort -u | tail -1 > /tmp/result.$1
  	else
  		cat /proc/cpuinfo | grep MHz | sort -u > /tmp/result.$1
  	fi
  	./msr 0 >> /tmp/result.$1
  
  	max_perf_pct=$(cat /sys/devices/system/cpu/intel_pstate/max_perf_pct)
  	echo "max_perf_pct $max_perf_pct" >> /tmp/result.$1
  
  	for job in `jobs -p`
  	do
  		echo "waiting for job id $job"
  		wait $job
  	done
  }
  
  #
  # MAIN (ALL UNITS IN MHZ)
  #
  
  # Get the marketing frequency
  _mkt_freq=$(cat /proc/cpuinfo | grep -m 1 "model name" | awk '{print $NF}')
  _mkt_freq=$(echo $_mkt_freq | tr -d [:alpha:][:punct:])
  mkt_freq=${_mkt_freq}0
  
  # Get the ranges from cpupower
  _min_freq=$(cpupower frequency-info -l | tail -1 | awk ' { print $1 } ')
  min_freq=$(($_min_freq / 1000))
  _max_freq=$(cpupower frequency-info -l | tail -1 | awk ' { print $2 } ')
  max_freq=$(($_max_freq / 1000))
  
  
  for freq in `seq $max_freq -100 $min_freq`
  do
  	echo "Setting maximum frequency to $freq"
  	cpupower frequency-set -g powersave --max=${freq}MHz >& /dev/null
  	[ $EVALUATE_ONLY -eq 0 ] && run_test $freq
  done
  
  echo "=============================================================================="
  
  echo "The marketing frequency of the cpu is $mkt_freq MHz"
  echo "The maximum frequency of the cpu is $max_freq MHz"
  echo "The minimum frequency of the cpu is $min_freq MHz"
  
  cpupower frequency-set -g powersave --max=${max_freq}MHz >& /dev/null
  
  # make a pretty table
  echo "Target      Actual      Difference     MSR(0x199)     max_perf_pct"
  for freq in `seq $max_freq -100 $min_freq`
  do
  	result_freq=$(cat /tmp/result.${freq} | grep "cpu MHz" | awk ' { print $4 } ' | awk -F "." ' { print $1 } ')
  	msr=$(cat /tmp/result.${freq} | grep "msr" | awk ' { print $3 } ')
  	max_perf_pct=$(cat /tmp/result.${freq} | grep "max_perf_pct" | awk ' { print $2 } ' )
  	if [ $result_freq -eq $freq ]; then
  		echo " $freq        $result_freq             0          $msr         $(($max_perf_pct*3300))"
  	else
  		echo " $freq        $result_freq          $(($result_freq-$freq))          $msr          $(($max_perf_pct*$max_freq))"
  	fi
  done
  exit 0
  