1#!/bin/sh
2#
3# Copyright 2012 the V8 project authors. All rights reserved.
4# Redistribution and use in source and binary forms, with or without
5# modification, are permitted provided that the following conditions are
6# met:
7#
8#     * Redistributions of source code must retain the above copyright
9#       notice, this list of conditions and the following disclaimer.
10#     * Redistributions in binary form must reproduce the above
11#       copyright notice, this list of conditions and the following
12#       disclaimer in the documentation and/or other materials provided
13#       with the distribution.
14#     * Neither the name of Google Inc. nor the names of its
15#       contributors may be used to endorse or promote products derived
16#       from this software without specific prior written permission.
17#
18# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30########## Global variable definitions
31
32# Ensure that <your CPU clock> / $SAMPLE_EVERY_N_CYCLES < $MAXIMUM_SAMPLE_RATE.
33MAXIMUM_SAMPLE_RATE=10000000
34SAMPLE_EVERY_N_CYCLES=10000
35SAMPLE_RATE_CONFIG_FILE="/proc/sys/kernel/perf_event_max_sample_rate"
36KERNEL_MAP_CONFIG_FILE="/proc/sys/kernel/kptr_restrict"
37
38########## Usage
39
40usage() {
41cat << EOF
42usage: $0 <benchmark_command>
43
44Executes <benchmark_command> under observation by the kernel's "perf" \
45framework, then calls the low level tick processor to analyze the results.
46EOF
47}
48
49if [ $# -eq 0 ] || [ "$1" == "-h" ]  || [ "$1" == "--help" ] ; then
50  usage
51  exit 1
52fi
53
54########## Actual script execution
55
56ACTUAL_SAMPLE_RATE=$(cat $SAMPLE_RATE_CONFIG_FILE)
57if [ "$ACTUAL_SAMPLE_RATE" -lt "$MAXIMUM_SAMPLE_RATE" ] ; then
58  echo "Setting appropriate maximum sample rate..."
59  echo $MAXIMUM_SAMPLE_RATE | sudo tee $SAMPLE_RATE_CONFIG_FILE
60fi
61
62ACTUAL_KERNEL_MAP_RESTRICTION=$(cat $KERNEL_MAP_CONFIG_FILE)
63if [ "$ACTUAL_KERNEL_MAP_RESTRICTION" -ne "0" ] ; then
64  echo "Disabling kernel address map restriction..."
65  echo 0 | sudo tee $KERNEL_MAP_CONFIG_FILE
66fi
67
68echo "Running benchmark..."
69perf record -R -e cycles -c $SAMPLE_EVERY_N_CYCLES -i $@ --ll-prof
70