tools/perf/perf-with-kcore.sh

   1 #!/bin/bash
   2 # perf-with-kcore: use perf with a copy of kcore
   3 # Copyright (c) 2014, Intel Corporation.
   4 #
   5 # This program is free software; you can redistribute it and/or modify it
   6 # under the terms and conditions of the GNU General Public License,
   7 # version 2, as published by the Free Software Foundation.
   8 #
   9 # This program is distributed in the hope it will be useful, but WITHOUT
  10 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 # more details.
  13
  14 set -e
  15
  16 usage()
  17 {
  18         echo "Usage: perf-with-kcore <perf sub-command> <perf.data directory> [<sub-command options> [ -- <workload>]]" >&2
  19         echo "       <perf sub-command> can be record, script, report or inject" >&2
  20         echo "   or: perf-with-kcore fix_buildid_cache_permissions" >&2
  21         exit 1
  22 }
  23
  24 find_perf()
  25 {
  26         if [ -n "$PERF" ] ; then
  27                 return
  28         fi
  29         PERF=`which perf || true`
  30         if [ -z "$PERF" ] ; then
  31                 echo "Failed to find perf" >&2
  32                 exit 1
  33         fi
  34         if [ ! -x "$PERF" ] ; then
  35                 echo "Failed to find perf" >&2
  36                 exit 1
  37         fi
  38         echo "Using $PERF"
  39         "$PERF" version
  40 }
  41
  42 copy_kcore()
  43 {
  44         echo "Copying kcore"
  45
  46         if [ $EUID -eq 0 ] ; then
  47                 SUDO=""
  48         else
  49                 SUDO="sudo"
  50         fi
  51
  52         rm -f perf.data.junk
  53         ("$PERF" record -o perf.data.junk $PERF_OPTIONS -- sleep 60) >/dev/null 2>/dev/null &
  54         PERF_PID=$!
  55
  56         # Need to make sure that perf has started
  57         sleep 1
  58
  59         KCORE=$(($SUDO "$PERF" buildid-cache -v -f -k /proc/kcore >/dev/null) 2>&1)
  60         case "$KCORE" in
  61         "kcore added to build-id cache directory "*)
  62                 KCORE_DIR=${KCORE#"kcore added to build-id cache directory "}
  63         ;;
  64         *)
  65                 kill $PERF_PID
  66                 wait >/dev/null 2>/dev/null || true
  67                 rm perf.data.junk
  68                 echo "$KCORE"
  69                 echo "Failed to find kcore" >&2
  70                 exit 1
  71         ;;
  72         esac
  73
  74         kill $PERF_PID
  75         wait >/dev/null 2>/dev/null || true
  76         rm perf.data.junk
  77
  78         $SUDO cp -a "$KCORE_DIR" "$(pwd)/$PERF_DATA_DIR"
  79         $SUDO rm -f "$KCORE_DIR/kcore"
  80         $SUDO rm -f "$KCORE_DIR/kallsyms"
  81         $SUDO rm -f "$KCORE_DIR/modules"
  82         $SUDO rmdir "$KCORE_DIR"
  83
  84         KCORE_DIR_BASENAME=$(basename "$KCORE_DIR")
  85         KCORE_DIR="$(pwd)/$PERF_DATA_DIR/$KCORE_DIR_BASENAME"
  86
  87         $SUDO chown $UID "$KCORE_DIR"
  88         $SUDO chown $UID "$KCORE_DIR/kcore"
  89         $SUDO chown $UID "$KCORE_DIR/kallsyms"
  90         $SUDO chown $UID "$KCORE_DIR/modules"
  91
  92         $SUDO chgrp $GROUPS "$KCORE_DIR"
  93         $SUDO chgrp $GROUPS "$KCORE_DIR/kcore"
  94         $SUDO chgrp $GROUPS "$KCORE_DIR/kallsyms"
  95         $SUDO chgrp $GROUPS "$KCORE_DIR/modules"
  96
  97         ln -s "$KCORE_DIR_BASENAME" "$PERF_DATA_DIR/kcore_dir"
  98 }
  99
 100 fix_buildid_cache_permissions()
 101 {
 102         if [ $EUID -ne 0 ] ; then
 103                 echo "This script must be run as root via sudo " >&2
 104                 exit 1
 105         fi
 106
 107         if [ -z "$SUDO_USER" ] ; then
 108                 echo "This script must be run via sudo" >&2
 109                 exit 1
 110         fi
 111
 112         USER_HOME=$(bash <<< "echo ~$SUDO_USER")
 113
 114         if [ "$HOME" != "$USER_HOME" ] ; then
 115                 echo "Fix unnecessary because root has a home: $HOME" >&2
 116                 exit 1
 117         fi
 118
 119         echo "Fixing buildid cache permissions"
 120
 121         find "$USER_HOME/.debug" -xdev -type d          ! -user "$SUDO_USER" -ls -exec chown    "$SUDO_USER" \{\} \;
 122         find "$USER_HOME/.debug" -xdev -type f -links 1 ! -user "$SUDO_USER" -ls -exec chown    "$SUDO_USER" \{\} \;
 123         find "$USER_HOME/.debug" -xdev -type l          ! -user "$SUDO_USER" -ls -exec chown -h "$SUDO_USER" \{\} \;
 124
 125         if [ -n "$SUDO_GID" ] ; then
 126                 find "$USER_HOME/.debug" -xdev -type d          ! -group "$SUDO_GID" -ls -exec chgrp    "$SUDO_GID" \{\} \;
 127                 find "$USER_HOME/.debug" -xdev -type f -links 1 ! -group "$SUDO_GID" -ls -exec chgrp    "$SUDO_GID" \{\} \;
 128                 find "$USER_HOME/.debug" -xdev -type l          ! -group "$SUDO_GID" -ls -exec chgrp -h "$SUDO_GID" \{\} \;
 129         fi
 130
 131         echo "Done"
 132 }
 133
 134 check_buildid_cache_permissions()
 135 {
 136         if [ $EUID -eq 0 ] ; then
 137                 return
 138         fi
 139
 140         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type d          ! -user "$USER" -print -quit)
 141         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type f -links 1 ! -user "$USER" -print -quit)
 142         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type l          ! -user "$USER" -print -quit)
 143
 144         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type d          ! -group "$GROUPS" -print -quit)
 145         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type f -links 1 ! -group "$GROUPS" -print -quit)
 146         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type l          ! -group "$GROUPS" -print -quit)
 147
 148         if [ -n "$PERMISSIONS_OK" ] ; then
 149                 echo "*** WARNING *** buildid cache permissions may need fixing" >&2
 150         fi
 151 }
 152
 153 record()
 154 {
 155         echo "Recording"
 156
 157         if [ $EUID -ne 0 ] ; then
 158
 159                 if [ "$(cat /proc/sys/kernel/kptr_restrict)" -ne 0 ] ; then
 160                         echo "*** WARNING *** /proc/sys/kernel/kptr_restrict prevents access to kernel addresses" >&2
 161                 fi
 162
 163                 if echo "$PERF_OPTIONS" | grep -q ' -a \|^-a \| -a$\|^-a$\| --all-cpus \|^--all-cpus \| --all-cpus$\|^--all-cpus$' ; then
 164                         echo "*** WARNING *** system-wide tracing without root access will not be able to read all necessary information from /proc" >&2
 165                 fi
 166
 167                 if echo "$PERF_OPTIONS" | grep -q 'intel_pt\|intel_bts\| -I\|^-I' ; then
 168                         if [ "$(cat /proc/sys/kernel/perf_event_paranoid)" -gt -1 ] ; then
 169                                 echo "*** WARNING *** /proc/sys/kernel/perf_event_paranoid restricts buffer size and tracepoint (sched_switch) use" >&2
 170                         fi
 171
 172                         if echo "$PERF_OPTIONS" | grep -q ' --per-thread \|^--per-thread \| --per-thread$\|^--per-thread$' ; then
 173                                 true
 174                         elif echo "$PERF_OPTIONS" | grep -q ' -t \|^-t \| -t$\|^-t$' ; then
 175                                 true
 176                         elif [ ! -r /sys/kernel/debug -o ! -x /sys/kernel/debug ] ; then
 177                                 echo "*** WARNING *** /sys/kernel/debug permissions prevent tracepoint (sched_switch) use" >&2
 178                         fi
 179                 fi
 180         fi
 181
 182         if [ -z "$1" ] ; then
 183                 echo "Workload is required for recording" >&2
 184                 usage
 185         fi
 186
 187         if [ -e "$PERF_DATA_DIR" ] ; then
 188                 echo "'$PERF_DATA_DIR' exists" >&2
 189                 exit 1
 190         fi
 191
 192         find_perf
 193
 194         mkdir "$PERF_DATA_DIR"
 195
 196         echo "$PERF record -o $PERF_DATA_DIR/perf.data $PERF_OPTIONS -- $*"
 197         "$PERF" record -o "$PERF_DATA_DIR/perf.data" $PERF_OPTIONS -- $* || true
 198
 199         if rmdir "$PERF_DATA_DIR" > /dev/null 2>/dev/null ; then
 200                 exit 1
 201         fi
 202
 203         copy_kcore
 204
 205         echo "Done"
 206 }
 207
 208 subcommand()
 209 {
 210         find_perf
 211         check_buildid_cache_permissions
 212         echo "$PERF $PERF_SUB_COMMAND -i $PERF_DATA_DIR/perf.data --kallsyms=$PERF_DATA_DIR/kcore_dir/kallsyms $*"
 213         "$PERF" $PERF_SUB_COMMAND -i "$PERF_DATA_DIR/perf.data" "--kallsyms=$PERF_DATA_DIR/kcore_dir/kallsyms" $*
 214 }
 215
 216 if [ "$1" = "fix_buildid_cache_permissions" ] ; then
 217         fix_buildid_cache_permissions
 218         exit 0
 219 fi
 220
 221 PERF_SUB_COMMAND=$1
 222 PERF_DATA_DIR=$2
 223 shift || true
 224 shift || true
 225
 226 if [ -z "$PERF_SUB_COMMAND" ] ; then
 227         usage
 228 fi
 229
 230 if [ -z "$PERF_DATA_DIR" ] ; then
 231         usage
 232 fi
 233
 234 case "$PERF_SUB_COMMAND" in
 235 "record")
 236         while [ "$1" != "--" ] ; do
 237                 PERF_OPTIONS+="$1 "
 238                 shift || break
 239         done
 240         if [ "$1" != "--" ] ; then
 241                 echo "Options and workload are required for recording" >&2
 242                 usage
 243         fi
 244         shift
 245         record $*
 246 ;;
 247 "script")
 248         subcommand $*
 249 ;;
 250 "report")
 251         subcommand $*
 252 ;;
 253 "inject")
 254         subcommand $*
 255 ;;
 256 *)
 257         usage
 258 ;;
 259 esac