1#!/bin/bash 2# perf record LBR tests (exclusive) 3# SPDX-License-Identifier: GPL-2.0 4 5set -e 6 7ParanoidAndNotRoot() { 8 [ "$(id -u)" != 0 ] && [ "$(cat /proc/sys/kernel/perf_event_paranoid)" -gt $1 ] 9} 10 11if [ ! -f /sys/bus/event_source/devices/cpu/caps/branches ] && 12 [ ! -f /sys/bus/event_source/devices/cpu_core/caps/branches ] 13then 14 echo "Skip: only x86 CPUs support LBR" 15 exit 2 16fi 17 18err=0 19perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX) 20 21cleanup() { 22 rm -rf "${perfdata}" 23 rm -rf "${perfdata}".old 24 rm -rf "${perfdata}".txt 25 26 trap - EXIT TERM INT 27} 28 29trap_cleanup() { 30 echo "Unexpected signal in ${FUNCNAME[1]}" 31 cleanup 32 exit 1 33} 34trap trap_cleanup EXIT TERM INT 35 36 37lbr_callgraph_test() { 38 test="LBR callgraph" 39 40 echo "$test" 41 if ! perf record -e cycles --call-graph lbr -o "${perfdata}" perf test -w thloop 42 then 43 echo "$test [Failed support missing]" 44 if [ $err -eq 0 ] 45 then 46 err=2 47 fi 48 return 49 fi 50 51 if ! perf report --stitch-lbr -i "${perfdata}" > "${perfdata}".txt 52 then 53 cat "${perfdata}".txt 54 echo "$test [Failed in perf report]" 55 err=1 56 return 57 fi 58 59 echo "$test [Success]" 60} 61 62lbr_test() { 63 local branch_flags=$1 64 local test="LBR $2 test" 65 local threshold=$3 66 local out 67 local sam_nr 68 local bs_nr 69 local zero_nr 70 local r 71 72 echo "$test" 73 if ! perf record -e cycles $branch_flags -o "${perfdata}" perf test -w thloop 74 then 75 echo "$test [Failed support missing]" 76 perf record -e cycles $branch_flags -o "${perfdata}" perf test -w thloop || true 77 if [ $err -eq 0 ] 78 then 79 err=2 80 fi 81 return 82 fi 83 84 out=$(perf report -D -i "${perfdata}" 2> /dev/null | grep -A1 'PERF_RECORD_SAMPLE') 85 sam_nr=$(echo "$out" | grep -c 'PERF_RECORD_SAMPLE' || true) 86 if [ $sam_nr -eq 0 ] 87 then 88 echo "$test [Failed no samples captured]" 89 err=1 90 return 91 fi 92 echo "$test: $sam_nr samples" 93 94 bs_nr=$(echo "$out" | grep -c 'branch stack: nr:' || true) 95 if [ $sam_nr -ne $bs_nr ] 96 then 97 echo "$test [Failed samples missing branch stacks]" 98 err=1 99 return 100 fi 101 102 zero_nr=$(echo "$out" | grep -A3 'branch stack: nr:0' | grep thread | grep -cv swapper || true) 103 r=$(($zero_nr * 100 / $bs_nr)) 104 if [ $r -gt $threshold ]; then 105 echo "$test [Failed empty br stack ratio exceed $threshold%: $r%]" 106 err=1 107 return 108 fi 109 110 echo "$test [Success]" 111} 112 113parallel_lbr_test() { 114 err=0 115 perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX) 116 lbr_test "$1" "$2" "$3" 117 cleanup 118 exit $err 119} 120 121lbr_callgraph_test 122 123# Sequential 124lbr_test "-b" "any branch" 2 125lbr_test "-j any_call" "any call" 2 126lbr_test "-j any_ret" "any ret" 2 127lbr_test "-j ind_call" "any indirect call" 2 128lbr_test "-j ind_jmp" "any indirect jump" 100 129lbr_test "-j call" "direct calls" 2 130lbr_test "-j ind_call,u" "any indirect user call" 100 131if ! ParanoidAndNotRoot 1 132then 133 lbr_test "-a -b" "system wide any branch" 2 134 lbr_test "-a -j any_call" "system wide any call" 2 135fi 136 137# Parallel 138parallel_lbr_test "-b" "parallel any branch" 100 & 139pid1=$! 140parallel_lbr_test "-j any_call" "parallel any call" 100 & 141pid2=$! 142parallel_lbr_test "-j any_ret" "parallel any ret" 100 & 143pid3=$! 144parallel_lbr_test "-j ind_call" "parallel any indirect call" 100 & 145pid4=$! 146parallel_lbr_test "-j ind_jmp" "parallel any indirect jump" 100 & 147pid5=$! 148parallel_lbr_test "-j call" "parallel direct calls" 100 & 149pid6=$! 150parallel_lbr_test "-j ind_call,u" "parallel any indirect user call" 100 & 151pid7=$! 152if ParanoidAndNotRoot 1 153then 154 pid8= 155 pid9= 156else 157 parallel_lbr_test "-a -b" "parallel system wide any branch" 100 & 158 pid8=$! 159 parallel_lbr_test "-a -j any_call" "parallel system wide any call" 100 & 160 pid9=$! 161fi 162 163for pid in $pid1 $pid2 $pid3 $pid4 $pid5 $pid6 $pid7 $pid8 $pid9 164do 165 set +e 166 wait $pid 167 child_err=$? 168 set -e 169 if ([ $err -eq 2 ] && [ $child_err -eq 1 ]) || [ $err -eq 0 ] 170 then 171 err=$child_err 172 fi 173done 174 175cleanup 176exit $err 177