tools/perf/perf-with-kcore.sh

   1 #!/bin/bash
   2 # SPDX-License-Identifier: GPL-2.0-only
   3 # perf-with-kcore: use perf with a copy of kcore
   4 # Copyright (c) 2014, Intel Corporation.
   5 #
   6
   7 set -e
   8
   9 usage()
  10 {
  11         echo "Usage: perf-with-kcore <perf sub-command> <perf.data directory> [<sub-command options> [ -- <workload>]]" >&2
  12         echo "       <perf sub-command> can be record, script, report or inject" >&2
  13         echo "   or: perf-with-kcore fix_buildid_cache_permissions" >&2
  14         exit 1
  15 }
  16
  17 find_perf()
  18 {
  19         if [ -n "$PERF" ] ; then
  20                 return
  21         fi
  22         PERF=`which perf || true`
  23         if [ -z "$PERF" ] ; then
  24                 echo "Failed to find perf" >&2
  25                 exit 1
  26         fi
  27         if [ ! -x "$PERF" ] ; then
  28                 echo "Failed to find perf" >&2
  29                 exit 1
  30         fi
  31         echo "Using $PERF"
  32         "$PERF" version
  33 }
  34
  35 copy_kcore()
  36 {
  37         echo "Copying kcore"
  38
  39         if [ $EUID -eq 0 ] ; then
  40                 SUDO=""
  41         else
  42                 SUDO="sudo"
  43         fi
  44
  45         rm -f perf.data.junk
  46         ("$PERF" record -o perf.data.junk "${PERF_OPTIONS[@]}" -- sleep 60) >/dev/null 2>/dev/null &
  47         PERF_PID=$!
  48
  49         # Need to make sure that perf has started
  50         sleep 1
  51
  52         KCORE=$(($SUDO "$PERF" buildid-cache -v -f -k /proc/kcore >/dev/null) 2>&1)
  53         case "$KCORE" in
  54         "kcore added to build-id cache directory "*)
  55                 KCORE_DIR=${KCORE#"kcore added to build-id cache directory "}
  56         ;;
  57         *)
  58                 kill $PERF_PID
  59                 wait >/dev/null 2>/dev/null || true
  60                 rm perf.data.junk
  61                 echo "$KCORE"
  62                 echo "Failed to find kcore" >&2
  63                 exit 1
  64         ;;
  65         esac
  66
  67         kill $PERF_PID
  68         wait >/dev/null 2>/dev/null || true
  69         rm perf.data.junk
  70
  71         $SUDO cp -a "$KCORE_DIR" "$(pwd)/$PERF_DATA_DIR"
  72         $SUDO rm -f "$KCORE_DIR/kcore"
  73         $SUDO rm -f "$KCORE_DIR/kallsyms"
  74         $SUDO rm -f "$KCORE_DIR/modules"
  75         $SUDO rmdir "$KCORE_DIR"
  76
  77         KCORE_DIR_BASENAME=$(basename "$KCORE_DIR")
  78         KCORE_DIR="$(pwd)/$PERF_DATA_DIR/$KCORE_DIR_BASENAME"
  79
  80         $SUDO chown $UID "$KCORE_DIR"
  81         $SUDO chown $UID "$KCORE_DIR/kcore"
  82         $SUDO chown $UID "$KCORE_DIR/kallsyms"
  83         $SUDO chown $UID "$KCORE_DIR/modules"
  84
  85         $SUDO chgrp $GROUPS "$KCORE_DIR"
  86         $SUDO chgrp $GROUPS "$KCORE_DIR/kcore"
  87         $SUDO chgrp $GROUPS "$KCORE_DIR/kallsyms"
  88         $SUDO chgrp $GROUPS "$KCORE_DIR/modules"
  89
  90         ln -s "$KCORE_DIR_BASENAME" "$PERF_DATA_DIR/kcore_dir"
  91 }
  92
  93 fix_buildid_cache_permissions()
  94 {
  95         if [ $EUID -ne 0 ] ; then
  96                 echo "This script must be run as root via sudo " >&2
  97                 exit 1
  98         fi
  99
 100         if [ -z "$SUDO_USER" ] ; then
 101                 echo "This script must be run via sudo" >&2
 102                 exit 1
 103         fi
 104
 105         USER_HOME=$(bash <<< "echo ~$SUDO_USER")
 106
 107         echo "Fixing buildid cache permissions"
 108
 109         find "$USER_HOME/.debug" -xdev -type d          ! -user "$SUDO_USER" -ls -exec chown    "$SUDO_USER" \{\} \;
 110         find "$USER_HOME/.debug" -xdev -type f -links 1 ! -user "$SUDO_USER" -ls -exec chown    "$SUDO_USER" \{\} \;
 111         find "$USER_HOME/.debug" -xdev -type l          ! -user "$SUDO_USER" -ls -exec chown -h "$SUDO_USER" \{\} \;
 112
 113         if [ -n "$SUDO_GID" ] ; then
 114                 find "$USER_HOME/.debug" -xdev -type d          ! -group "$SUDO_GID" -ls -exec chgrp    "$SUDO_GID" \{\} \;
 115                 find "$USER_HOME/.debug" -xdev -type f -links 1 ! -group "$SUDO_GID" -ls -exec chgrp    "$SUDO_GID" \{\} \;
 116                 find "$USER_HOME/.debug" -xdev -type l          ! -group "$SUDO_GID" -ls -exec chgrp -h "$SUDO_GID" \{\} \;
 117         fi
 118
 119         echo "Done"
 120 }
 121
 122 check_buildid_cache_permissions()
 123 {
 124         if [ $EUID -eq 0 ] ; then
 125                 return
 126         fi
 127
 128         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type d          ! -user "$USER" -print -quit)
 129         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type f -links 1 ! -user "$USER" -print -quit)
 130         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type l          ! -user "$USER" -print -quit)
 131
 132         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type d          ! -group "$GROUPS" -print -quit)
 133         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type f -links 1 ! -group "$GROUPS" -print -quit)
 134         PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type l          ! -group "$GROUPS" -print -quit)
 135
 136         if [ -n "$PERMISSIONS_OK" ] ; then
 137                 echo "*** WARNING *** buildid cache permissions may need fixing" >&2
 138         fi
 139 }
 140
 141 record()
 142 {
 143         echo "Recording"
 144
 145         if [ $EUID -ne 0 ] ; then
 146
 147                 if [ "$(cat /proc/sys/kernel/kptr_restrict)" -ne 0 ] ; then
 148                         echo "*** WARNING *** /proc/sys/kernel/kptr_restrict prevents access to kernel addresses" >&2
 149                 fi
 150
 151                 if echo "${PERF_OPTIONS[@]}" | grep -q ' -a \|^-a \| -a$\|^-a$\| --all-cpus \|^--all-cpus \| --all-cpus$\|^--all-cpus$' ; then
 152                         echo "*** WARNING *** system-wide tracing without root access will not be able to read all necessary information from /proc" >&2
 153                 fi
 154
 155                 if echo "${PERF_OPTIONS[@]}" | grep -q 'intel_pt\|intel_bts\| -I\|^-I' ; then
 156                         if [ "$(cat /proc/sys/kernel/perf_event_paranoid)" -gt -1 ] ; then
 157                                 echo "*** WARNING *** /proc/sys/kernel/perf_event_paranoid restricts buffer size and tracepoint (sched_switch) use" >&2
 158                         fi
 159
 160                         if echo "${PERF_OPTIONS[@]}" | grep -q ' --per-thread \|^--per-thread \| --per-thread$\|^--per-thread$' ; then
 161                                 true
 162                         elif echo "${PERF_OPTIONS[@]}" | grep -q ' -t \|^-t \| -t$\|^-t$' ; then
 163                                 true
 164                         elif [ ! -r /sys/kernel/debug -o ! -x /sys/kernel/debug ] ; then
 165                                 echo "*** WARNING *** /sys/kernel/debug permissions prevent tracepoint (sched_switch) use" >&2
 166                         fi
 167                 fi
 168         fi
 169
 170         if [ -z "$1" ] ; then
 171                 echo "Workload is required for recording" >&2
 172                 usage
 173         fi
 174
 175         if [ -e "$PERF_DATA_DIR" ] ; then
 176                 echo "'$PERF_DATA_DIR' exists" >&2
 177                 exit 1
 178         fi
 179
 180         find_perf
 181
 182         mkdir "$PERF_DATA_DIR"
 183
 184         echo "$PERF record -o $PERF_DATA_DIR/perf.data ${PERF_OPTIONS[@]} -- $@"
 185         "$PERF" record -o "$PERF_DATA_DIR/perf.data" "${PERF_OPTIONS[@]}" -- "$@" || true
 186
 187         if rmdir "$PERF_DATA_DIR" > /dev/null 2>/dev/null ; then
 188                 exit 1
 189         fi
 190
 191         copy_kcore
 192
 193         echo "Done"
 194 }
 195
 196 subcommand()
 197 {
 198         find_perf
 199         check_buildid_cache_permissions
 200         echo "$PERF $PERF_SUB_COMMAND -i $PERF_DATA_DIR/perf.data --kallsyms=$PERF_DATA_DIR/kcore_dir/kallsyms $@"
 201         "$PERF" $PERF_SUB_COMMAND -i "$PERF_DATA_DIR/perf.data" "--kallsyms=$PERF_DATA_DIR/kcore_dir/kallsyms" "$@"
 202 }
 203
 204 if [ "$1" = "fix_buildid_cache_permissions" ] ; then
 205         fix_buildid_cache_permissions
 206         exit 0
 207 fi
 208
 209 PERF_SUB_COMMAND=$1
 210 PERF_DATA_DIR=$2
 211 shift || true
 212 shift || true
 213
 214 if [ -z "$PERF_SUB_COMMAND" ] ; then
 215         usage
 216 fi
 217
 218 if [ -z "$PERF_DATA_DIR" ] ; then
 219         usage
 220 fi
 221
 222 case "$PERF_SUB_COMMAND" in
 223 "record")
 224         while [ "$1" != "--" ] ; do
 225                 PERF_OPTIONS+=("$1")
 226                 shift || break
 227         done
 228         if [ "$1" != "--" ] ; then
 229                 echo "Options and workload are required for recording" >&2
 230                 usage
 231         fi
 232         shift
 233         record "$@"
 234 ;;
 235 "script")
 236         subcommand "$@"
 237 ;;
 238 "report")
 239         subcommand "$@"
 240 ;;
 241 "inject")
 242         subcommand "$@"
 243 ;;
 244 *)
 245         usage
 246 ;;
 247 esac