summaryrefslogtreecommitdiff
path: root/tools/perf/perf-with-kcore.sh
diff options
context:
space:
mode:
authorAdrian Hunter <adrian.hunter@intel.com>2014-07-31 10:01:12 +0400
committerArnaldo Carvalho de Melo <acme@redhat.com>2014-09-18 00:08:08 +0400
commitc501e90b4700e4f247ccdcf5ae81f9846a2ef5f9 (patch)
treecc991758edf8e578e9278f0b0ba5ea660fe4638e /tools/perf/perf-with-kcore.sh
parentad96227349901838e1a7f96f1dc22d96a97520c0 (diff)
downloadlinux-c501e90b4700e4f247ccdcf5ae81f9846a2ef5f9.tar.xz
perf tools: Add perf-with-kcore script
Decoding an Intel PT trace of the kernel requires an accurate kernel object image. This is provided by making a copy of kcore. However the copy needs to be made under the same conditions as the original recording, and then it needs to be associated with the perf.data file. The perf-with-kcore script does that. The script also checks the permissions on the buildid cache and can be used to fix them. That is needed for distributions where root does not have a home directory and consequently writes to the same buildid cache as the user, resulting in cached files that the user does not have access to. Example: $ ./perf-with-kcore Usage: perf-with-kcore <perf sub-command> <perf.data directory> [<sub-command options> [ -- <workload>]] <perf sub-command> can be record, script, report or inject or: perf-with-kcore fix_buildid_cache_permissions $ ./perf-with-kcore record pt_uname -e intel_pt// -- uname Recording Using /home/ahunter/bin/perf perf version 3.15.rc3.g4549ba /home/ahunter/bin/perf record -o pt_uname/perf.data -e intel_pt// -- uname Linux [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.023 MB pt_uname/perf.data ] Copying kcore [sudo] password for ahunter: Done $ tools/perf/perf-with-kcore.sh script pt_uname | head Using /home/ahunter/bin/perf perf version 3.15.rc3.g4549ba /home/ahunter/bin/perf script -i pt_uname/perf.data --kallsyms=pt_uname/kcore_dir/kallsyms swapper 0 [002] 161533.969666: sched:sched_switch: swapper/2:0 [120] R ==> perf:11316 [120] :11315 11315 [003] 161533.969704: sched:sched_switch: perf:11315 [120] S ==> swapper/3:0 [120] :11316 11316 [002] 161533.969783: sched:sched_switch: perf:11316 [120] R ==> migration/2:33 [0] :33 33 [002] 161533.969791: sched:sched_switch: migration/2:33 [0] S ==> swapper/2:0 [120] swapper 0 [003] 161533.969792: sched:sched_switch: swapper/3:0 [120] R ==> perf:11316 [120] :11316 11316 [003] 161533.970062: branches: 0 [unknown] ([unknown]) => ffffffff810532fa native_write_msr_safe ([kernel.kallsyms]) :11316 11316 [003] 161533.970062: branches: ffffffff810532fd native_write_msr_safe ([kernel.kallsyms]) => ffffffff81035b31 pt_config_start ([kernel.kallsyms]) Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1406786474-9306-30-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/perf-with-kcore.sh')
-rw-r--r--tools/perf/perf-with-kcore.sh259
1 files changed, 259 insertions, 0 deletions
diff --git a/tools/perf/perf-with-kcore.sh b/tools/perf/perf-with-kcore.sh
new file mode 100644
index 000000000000..c7ff90a90e4e
--- /dev/null
+++ b/tools/perf/perf-with-kcore.sh
@@ -0,0 +1,259 @@
+#!/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