swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: f22e6e847115abc3a0e2ad7bb18d243d42275af1 authored by Linus Torvalds on 06 April 2015, 22:39:45 UTC
Linux 4.0-rc7
Linux 4.0-rc7
Tip revision: f22e6e8
perf-with-kcore.sh
#!/bin/bash
# perf-with-kcore: use perf with a copy of kcore
# Copyright (c) 2014, Intel Corporation.
#
# This program is free software; you can redistribute it and/or modify it
# under the terms and conditions of the GNU General Public License,
# version 2, as published by the Free Software Foundation.
#
# This program is distributed in the hope it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
# more details.
set -e
usage()
{
echo "Usage: perf-with-kcore <perf sub-command> <perf.data directory> [<sub-command options> [ -- <workload>]]" >&2
echo " <perf sub-command> can be record, script, report or inject" >&2
echo " or: perf-with-kcore fix_buildid_cache_permissions" >&2
exit 1
}
find_perf()
{
if [ -n "$PERF" ] ; then
return
fi
PERF=`which perf || true`
if [ -z "$PERF" ] ; then
echo "Failed to find perf" >&2
exit 1
fi
if [ ! -x "$PERF" ] ; then
echo "Failed to find perf" >&2
exit 1
fi
echo "Using $PERF"
"$PERF" version
}
copy_kcore()
{
echo "Copying kcore"
if [ $EUID -eq 0 ] ; then
SUDO=""
else
SUDO="sudo"
fi
rm -f perf.data.junk
("$PERF" record -o perf.data.junk $PERF_OPTIONS -- sleep 60) >/dev/null 2>/dev/null &
PERF_PID=$!
# Need to make sure that perf has started
sleep 1
KCORE=$(($SUDO "$PERF" buildid-cache -v -f -k /proc/kcore >/dev/null) 2>&1)
case "$KCORE" in
"kcore added to build-id cache directory "*)
KCORE_DIR=${KCORE#"kcore added to build-id cache directory "}
;;
*)
kill $PERF_PID
wait >/dev/null 2>/dev/null || true
rm perf.data.junk
echo "$KCORE"
echo "Failed to find kcore" >&2
exit 1
;;
esac
kill $PERF_PID
wait >/dev/null 2>/dev/null || true
rm perf.data.junk
$SUDO cp -a "$KCORE_DIR" "$(pwd)/$PERF_DATA_DIR"
$SUDO rm -f "$KCORE_DIR/kcore"
$SUDO rm -f "$KCORE_DIR/kallsyms"
$SUDO rm -f "$KCORE_DIR/modules"
$SUDO rmdir "$KCORE_DIR"
KCORE_DIR_BASENAME=$(basename "$KCORE_DIR")
KCORE_DIR="$(pwd)/$PERF_DATA_DIR/$KCORE_DIR_BASENAME"
$SUDO chown $UID "$KCORE_DIR"
$SUDO chown $UID "$KCORE_DIR/kcore"
$SUDO chown $UID "$KCORE_DIR/kallsyms"
$SUDO chown $UID "$KCORE_DIR/modules"
$SUDO chgrp $GROUPS "$KCORE_DIR"
$SUDO chgrp $GROUPS "$KCORE_DIR/kcore"
$SUDO chgrp $GROUPS "$KCORE_DIR/kallsyms"
$SUDO chgrp $GROUPS "$KCORE_DIR/modules"
ln -s "$KCORE_DIR_BASENAME" "$PERF_DATA_DIR/kcore_dir"
}
fix_buildid_cache_permissions()
{
if [ $EUID -ne 0 ] ; then
echo "This script must be run as root via sudo " >&2
exit 1
fi
if [ -z "$SUDO_USER" ] ; then
echo "This script must be run via sudo" >&2
exit 1
fi
USER_HOME=$(bash <<< "echo ~$SUDO_USER")
if [ "$HOME" != "$USER_HOME" ] ; then
echo "Fix unnecessary because root has a home: $HOME" >&2
exit 1
fi
echo "Fixing buildid cache permissions"
find "$USER_HOME/.debug" -xdev -type d ! -user "$SUDO_USER" -ls -exec chown "$SUDO_USER" \{\} \;
find "$USER_HOME/.debug" -xdev -type f -links 1 ! -user "$SUDO_USER" -ls -exec chown "$SUDO_USER" \{\} \;
find "$USER_HOME/.debug" -xdev -type l ! -user "$SUDO_USER" -ls -exec chown -h "$SUDO_USER" \{\} \;
if [ -n "$SUDO_GID" ] ; then
find "$USER_HOME/.debug" -xdev -type d ! -group "$SUDO_GID" -ls -exec chgrp "$SUDO_GID" \{\} \;
find "$USER_HOME/.debug" -xdev -type f -links 1 ! -group "$SUDO_GID" -ls -exec chgrp "$SUDO_GID" \{\} \;
find "$USER_HOME/.debug" -xdev -type l ! -group "$SUDO_GID" -ls -exec chgrp -h "$SUDO_GID" \{\} \;
fi
echo "Done"
}
check_buildid_cache_permissions()
{
if [ $EUID -eq 0 ] ; then
return
fi
PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type d ! -user "$USER" -print -quit)
PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type f -links 1 ! -user "$USER" -print -quit)
PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type l ! -user "$USER" -print -quit)
PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type d ! -group "$GROUPS" -print -quit)
PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type f -links 1 ! -group "$GROUPS" -print -quit)
PERMISSIONS_OK+=$(find "$HOME/.debug" -xdev -type l ! -group "$GROUPS" -print -quit)
if [ -n "$PERMISSIONS_OK" ] ; then
echo "*** WARNING *** buildid cache permissions may need fixing" >&2
fi
}
record()
{
echo "Recording"
if [ $EUID -ne 0 ] ; then
if [ "$(cat /proc/sys/kernel/kptr_restrict)" -ne 0 ] ; then
echo "*** WARNING *** /proc/sys/kernel/kptr_restrict prevents access to kernel addresses" >&2
fi
if echo "$PERF_OPTIONS" | grep -q ' -a \|^-a \| -a$\|^-a$\| --all-cpus \|^--all-cpus \| --all-cpus$\|^--all-cpus$' ; then
echo "*** WARNING *** system-wide tracing without root access will not be able to read all necessary information from /proc" >&2
fi
if echo "$PERF_OPTIONS" | grep -q 'intel_pt\|intel_bts\| -I\|^-I' ; then
if [ "$(cat /proc/sys/kernel/perf_event_paranoid)" -gt -1 ] ; then
echo "*** WARNING *** /proc/sys/kernel/perf_event_paranoid restricts buffer size and tracepoint (sched_switch) use" >&2
fi
if echo "$PERF_OPTIONS" | grep -q ' --per-thread \|^--per-thread \| --per-thread$\|^--per-thread$' ; then
true
elif echo "$PERF_OPTIONS" | grep -q ' -t \|^-t \| -t$\|^-t$' ; then
true
elif [ ! -r /sys/kernel/debug -o ! -x /sys/kernel/debug ] ; then
echo "*** WARNING *** /sys/kernel/debug permissions prevent tracepoint (sched_switch) use" >&2
fi
fi
fi
if [ -z "$1" ] ; then
echo "Workload is required for recording" >&2
usage
fi
if [ -e "$PERF_DATA_DIR" ] ; then
echo "'$PERF_DATA_DIR' exists" >&2
exit 1
fi
find_perf
mkdir "$PERF_DATA_DIR"
echo "$PERF record -o $PERF_DATA_DIR/perf.data $PERF_OPTIONS -- $*"
"$PERF" record -o "$PERF_DATA_DIR/perf.data" $PERF_OPTIONS -- $* || true
if rmdir "$PERF_DATA_DIR" > /dev/null 2>/dev/null ; then
exit 1
fi
copy_kcore
echo "Done"
}
subcommand()
{
find_perf
check_buildid_cache_permissions
echo "$PERF $PERF_SUB_COMMAND -i $PERF_DATA_DIR/perf.data --kallsyms=$PERF_DATA_DIR/kcore_dir/kallsyms $*"
"$PERF" $PERF_SUB_COMMAND -i "$PERF_DATA_DIR/perf.data" "--kallsyms=$PERF_DATA_DIR/kcore_dir/kallsyms" $*
}
if [ "$1" = "fix_buildid_cache_permissions" ] ; then
fix_buildid_cache_permissions
exit 0
fi
PERF_SUB_COMMAND=$1
PERF_DATA_DIR=$2
shift || true
shift || true
if [ -z "$PERF_SUB_COMMAND" ] ; then
usage
fi
if [ -z "$PERF_DATA_DIR" ] ; then
usage
fi
case "$PERF_SUB_COMMAND" in
"record")
while [ "$1" != "--" ] ; do
PERF_OPTIONS+="$1 "
shift || break
done
if [ "$1" != "--" ] ; then
echo "Options and workload are required for recording" >&2
usage
fi
shift
record $*
;;
"script")
subcommand $*
;;
"report")
subcommand $*
;;
"inject")
subcommand $*
;;
*)
usage
;;
esac