#!/bin/sh
# Check Arm CoreSight trace data recording and synthesized samples
# Uses the 'perf record' to record trace data with Arm CoreSight sinks;
# then verify if there have any branch samples and instruction samples
# are generated by CoreSight with 'perf script' and 'perf report'
# commands.
# SPDX-License-Identifier: GPL-2.0
# Leo Yan <[email protected]>, 2020
glb_err=0
skip_if_no_cs_etm_event() {
perf list | grep -q 'cs_etm//' && return 0
# cs_etm event doesn't exist
return 2
}
skip_if_no_cs_etm_event || exit 2
perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
file=$(mktemp /tmp/temporary_file.XXXXX)
cleanup_files()
{
rm -f ${perfdata}
rm -f ${file}
rm -f "${perfdata}.old"
trap - EXIT TERM INT
exit $glb_err
}
trap cleanup_files EXIT TERM INT
record_touch_file() {
echo "Recording trace (only user mode) with path: CPU$2 => $1"
rm -f $file
perf record -o ${perfdata} -e cs_etm/@$1/u --per-thread \
-- taskset -c $2 touch $file > /dev/null 2>&1
}
perf_script_branch_samples() {
echo "Looking at perf.data file for dumping branch samples:"
# Below is an example of the branch samples dumping:
# touch 6512 1 branches:u: ffffb220824c strcmp+0xc (/lib/aarch64-linux-gnu/ld-2.27.so)
# touch 6512 1 branches:u: ffffb22082e0 strcmp+0xa0 (/lib/aarch64-linux-gnu/ld-2.27.so)
# touch 6512 1 branches:u: ffffb2208320 strcmp+0xe0 (/lib/aarch64-linux-gnu/ld-2.27.so)
perf script -F,-time -i ${perfdata} 2>&1 | \
grep -E " +$1 +[0-9]+ .* +branches:(.*:)? +" > /dev/null 2>&1
}
perf_report_branch_samples() {
echo "Looking at perf.data file for reporting branch samples:"
# Below is an example of the branch samples reporting:
# 73.04% 73.04% touch libc-2.27.so [.] _dl_addr
# 7.71% 7.71% touch libc-2.27.so [.] getenv
# 2.59% 2.59% touch ld-2.27.so [.] strcmp
perf report --stdio -i ${perfdata} 2>&1 | \
grep -E " +[0-9]+\.[0-9]+% +[0-9]+\.[0-9]+% +$1 " > /dev/null 2>&1
}
perf_report_instruction_samples() {
echo "Looking at perf.data file for instruction samples:"
# Below is an example of the instruction samples reporting:
# 68.12% touch libc-2.27.so [.] _dl_addr
# 5.80% touch libc-2.27.so [.] getenv
# 4.35% touch ld-2.27.so [.] _dl_fixup
perf report --itrace=i20i --stdio -i ${perfdata} 2>&1 | \
grep -E " +[0-9]+\.[0-9]+% +$1" > /dev/null 2>&1
}
arm_cs_report() {
if [ $2 != 0 ]; then
echo "$1: FAIL"
glb_err=$2
else
echo "$1: PASS"
fi
}
is_device_sink() {
# If the node of "enable_sink" is existed under the device path, this
# means the device is a sink device. Need to exclude 'tpiu' since it
# cannot support perf PMU.
echo "$1" | grep -E -q -v "tpiu"
if [ $? -eq 0 ] && [ -e "$1/enable_sink" ]; then
pmu_dev="/sys/bus/event_source/devices/cs_etm/sinks/$2"
# Warn if the device is not supported by PMU
if ! [ -f $pmu_dev ]; then
echo "PMU doesn't support $pmu_dev"
fi
return 0
fi
# Otherwise, it's not a sink device
return 1
}
arm_cs_iterate_devices() {
for dev in $1/connections/out\:*; do
# Skip testing if it's not a directory
! [ -d $dev ] && continue;
# Read out its symbol link file name
path=`readlink -f $dev`
# Extract device name from path, e.g.
# path = '/sys/devices/platform/20010000.etf/tmc_etf0'
# `> device_name = 'tmc_etf0'
device_name=$(basename $path)
if is_device_sink $path $device_name; then
record_touch_file $device_name $2 &&
perf_script_branch_samples touch &&
perf_report_branch_samples touch &&
perf_report_instruction_samples touch
err=$?
arm_cs_report "CoreSight path testing (CPU$2 -> $device_name)" $err
fi
arm_cs_iterate_devices $dev $2
done
}
arm_cs_etm_traverse_path_test() {
# Iterate for every ETM device
for dev in /sys/bus/event_source/devices/cs_etm/cpu*; do
# Canonicalize the path
dev=`readlink -f $dev`
# Find the ETM device belonging to which CPU
cpu=`cat $dev/cpu`
# Use depth-first search (DFS) to iterate outputs
arm_cs_iterate_devices $dev $cpu
done
}
arm_cs_etm_system_wide_test() {
echo "Recording trace with system wide mode"
perf record -o ${perfdata} -e cs_etm// -a -- ls > /dev/null 2>&1
# System-wide mode should include perf samples so test for that
# instead of ls
perf_script_branch_samples perf &&
perf_report_branch_samples perf &&
perf_report_instruction_samples perf
err=$?
arm_cs_report "CoreSight system wide testing" $err
}
arm_cs_etm_snapshot_test() {
echo "Recording trace with snapshot mode"
perf record -o ${perfdata} -e cs_etm// -S \
-- dd if=/dev/zero of=/dev/null > /dev/null 2>&1 &
PERFPID=$!
# Wait for perf program
sleep 1
# Send signal to snapshot trace data
kill -USR2 $PERFPID
# Stop perf program
kill $PERFPID
wait $PERFPID
perf_script_branch_samples dd &&
perf_report_branch_samples dd &&
perf_report_instruction_samples dd
err=$?
arm_cs_report "CoreSight snapshot testing" $err
}
arm_cs_etm_basic_test() {
echo "Recording trace with '$*'"
perf record -o ${perfdata} "$@" -m,8M -- ls > /dev/null 2>&1
perf_script_branch_samples ls &&
perf_report_branch_samples ls &&
perf_report_instruction_samples ls
err=$?
arm_cs_report "CoreSight basic testing with '$*'" $err
}
arm_cs_etm_traverse_path_test
arm_cs_etm_system_wide_test
arm_cs_etm_snapshot_test
# Test all combinations of per-thread, system-wide and normal mode with
# and without timestamps
arm_cs_etm_basic_test -e cs_etm/timestamp=0/ --per-thread
arm_cs_etm_basic_test -e cs_etm/timestamp=1/ --per-thread
arm_cs_etm_basic_test -e cs_etm/timestamp=0/ -a
arm_cs_etm_basic_test -e cs_etm/timestamp=1/ -a
arm_cs_etm_basic_test -e cs_etm/timestamp=0/
arm_cs_etm_basic_test -e cs_etm/timestamp=1/
exit $glb_err
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