name : lock_contention.sh #!/bin/sh # kernel lock contention analysis test # SPDX-License-Identifier: GPL-2.0 set -e err=0 perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX) result=$(mktemp /tmp/__perf_test.result.XXXXX) cleanup() { rm -f ${perfdata} rm -f ${result} trap - EXIT TERM INT } trap_cleanup() { cleanup exit ${err} } trap trap_cleanup EXIT TERM INT check() { if [ "$(id -u)" != 0 ]; then echo "[Skip] No root permission" err=2 exit fi if ! perf list | grep -q lock:contention_begin; then echo "[Skip] No lock contention tracepoints" err=2 exit fi # shellcheck disable=SC2046 if [ `nproc` -lt 4 ]; then echo "[Skip] Low number of CPUs (`nproc`), lock event cannot be triggered certainly" err=2 exit fi } test_record() { echo "Testing perf lock record and perf lock contention" perf lock record -o ${perfdata} -- perf bench sched messaging > /dev/null 2>&1 # the output goes to the stderr and we expect only 1 output (-E 1) perf lock contention -i ${perfdata} -E 1 -q 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] Recorded result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi } test_bpf() { echo "Testing perf lock contention --use-bpf" if ! perf lock con -b true > /dev/null 2>&1 ; then echo "[Skip] No BPF support" return fi # the perf lock contention output goes to the stderr perf lock con -a -b -E 1 -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi } test_record_concurrent() { echo "Testing perf lock record and perf lock contention at the same time" perf lock record -o- -- perf bench sched messaging 2> /dev/null | \ perf lock contention -i- -E 1 -q 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] Recorded result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi } test_aggr_task() { echo "Testing perf lock contention --threads" perf lock contention -i ${perfdata} -t -E 1 -q 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] Recorded result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then return fi # the perf lock contention output goes to the stderr perf lock con -a -b -t -E 1 -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi } test_aggr_addr() { echo "Testing perf lock contention --lock-addr" perf lock contention -i ${perfdata} -l -E 1 -q 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] Recorded result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then return fi # the perf lock contention output goes to the stderr perf lock con -a -b -l -E 1 -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi } test_aggr_cgroup() { echo "Testing perf lock contention --lock-cgroup" if ! perf lock con -b true > /dev/null 2>&1 ; then echo "[Skip] No BPF support" return fi # the perf lock contention output goes to the stderr perf lock con -a -b -g -E 1 -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result count is not 1:" "$(cat "${result}" | wc -l)" err=1 exit fi } test_type_filter() { echo "Testing perf lock contention --type-filter (w/ spinlock)" perf lock contention -i ${perfdata} -Y spinlock -q 2> ${result} if [ "$(grep -c -v spinlock "${result}")" != "0" ]; then echo "[Fail] Recorded result should not have non-spinlocks:" "$(cat "${result}")" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then return fi perf lock con -a -b -Y spinlock -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(grep -c -v spinlock "${result}")" != "0" ]; then echo "[Fail] BPF result should not have non-spinlocks:" "$(cat "${result}")" err=1 exit fi } test_lock_filter() { echo "Testing perf lock contention --lock-filter (w/ tasklist_lock)" perf lock contention -i ${perfdata} -l -q 2> ${result} if [ "$(grep -c tasklist_lock "${result}")" != "1" ]; then echo "[Skip] Could not find 'tasklist_lock'" return fi perf lock contention -i ${perfdata} -L tasklist_lock -q 2> ${result} # find out the type of tasklist_lock test_lock_filter_type=$(head -1 "${result}" | awk '{ print $8 }' | sed -e 's/:.*//') if [ "$(grep -c -v "${test_lock_filter_type}" "${result}")" != "0" ]; then echo "[Fail] Recorded result should not have non-${test_lock_filter_type} locks:" "$(cat "${result}")" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then return fi perf lock con -a -b -L tasklist_lock -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(grep -c -v "${test_lock_filter_type}" "${result}")" != "0" ]; then echo "[Fail] BPF result should not have non-${test_lock_filter_type} locks:" "$(cat "${result}")" err=1 exit fi } test_stack_filter() { echo "Testing perf lock contention --callstack-filter (w/ unix_stream)" perf lock contention -i ${perfdata} -v -q 2> ${result} if [ "$(grep -c unix_stream "${result}")" = "0" ]; then echo "[Skip] Could not find 'unix_stream'" return fi perf lock contention -i ${perfdata} -E 1 -S unix_stream -q 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] Recorded result should have a lock from unix_stream:" "$(cat "${result}")" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then return fi perf lock con -a -b -S unix_stream -E 1 -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result should have a lock from unix_stream:" "$(cat "${result}")" err=1 exit fi } test_aggr_task_stack_filter() { echo "Testing perf lock contention --callstack-filter with task aggregation" perf lock contention -i ${perfdata} -v -q 2> ${result} if [ "$(grep -c unix_stream "${result}")" = "0" ]; then echo "[Skip] Could not find 'unix_stream'" return fi perf lock contention -i ${perfdata} -t -E 1 -S unix_stream -q 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] Recorded result should have a task from unix_stream:" "$(cat "${result}")" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then return fi perf lock con -a -b -t -S unix_stream -E 1 -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result should have a task from unix_stream:" "$(cat "${result}")" err=1 exit fi } test_cgroup_filter() { echo "Testing perf lock contention --cgroup-filter" if ! perf lock con -b true > /dev/null 2>&1 ; then echo "[Skip] No BPF support" return fi perf lock con -a -b -g -E 1 -F wait_total -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result should have a cgroup result:" "$(cat "${result}")" err=1 exit fi cgroup=$(cat "${result}" | awk '{ print $3 }') perf lock con -a -b -g -E 1 -G "${cgroup}" -q -- perf bench sched messaging > /dev/null 2> ${result} if [ "$(cat "${result}" | wc -l)" != "1" ]; then echo "[Fail] BPF result should have a result with cgroup filter:" "$(cat "${cgroup}")" err=1 exit fi } test_csv_output() { echo "Testing perf lock contention CSV output" perf lock contention -i ${perfdata} -E 1 -x , --output ${result} # count the number of commas in the header # it should have 5: contended, total-wait, max-wait, avg-wait, type, caller header=$(grep "# output:" ${result} | tr -d -c , | wc -c) if [ "${header}" != "5" ]; then echo "[Fail] Recorded result does not have enough output columns: ${header} != 5" err=1 exit fi # count the number of commas in the output output=$(grep -v "^#" ${result} | tr -d -c , | wc -c) if [ "${header}" != "${output}" ]; then echo "[Fail] Recorded result does not match the number of commas: ${header} != ${output}" err=1 exit fi if ! perf lock con -b true > /dev/null 2>&1 ; then echo "[Skip] No BPF support" return fi # the perf lock contention output goes to the stderr perf lock con -a -b -E 1 -x , --output ${result} -- perf bench sched messaging > /dev/null 2>&1 output=$(grep -v "^#" ${result} | tr -d -c , | wc -c) if [ "${header}" != "${output}" ]; then echo "[Fail] BPF result does not match the number of commas: ${header} != ${output}" err=1 exit fi } check test_record test_bpf test_record_concurrent test_aggr_task test_aggr_addr test_aggr_cgroup test_type_filter test_lock_filter test_stack_filter test_aggr_task_stack_filter test_cgroup_filter test_csv_output exit ${err}