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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249#!/bin/bash# Check branch stack sampling
# SPDX-License-Identifier: GPL-2.0# German Gomez <german.gomez@arm.com>, 2022
shelldir=$(dirname "$0")# shellcheck source=lib/perf_has_symbol.sh. "${shelldir}"/lib/perf_has_symbol.sh
# skip the test if the hardware doesn't support branch stack sampling# and if the architecture doesn't support filter types: any,save_type,uif ! perf record -o- --no-buildid --branch-filter any,save_type,u -- true > /dev/null 2>&1 ; then echo "skip: system doesn't support filter types: any,save_type,u" exit 2fi
skip_test_missing_symbol brstack_bench
err=0TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)TESTPROG="perf test -w brstack"
cleanup() { rm -rf $TMPDIR trap - EXIT TERM INT}
trap_cleanup() { set +e echo "Unexpected signal in ${FUNCNAME[1]}" cleanup exit 1}trap trap_cleanup EXIT TERM INT
is_arm64() { [ "$(uname -m)" = "aarch64" ];}
has_kaslr_bug() { [ "$(uname -m)" != "aarch64" ];}
check_branches() { if ! tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep -E -m1 -q "$1"; then echo "ERROR: Branches missing $1" err=1 fi}
test_user_branches() { echo "Testing user branch stack sampling"
start_err=$err err=0 perf record -o "$TMPDIR/perf.data" --branch-filter any,save_type,u -- ${TESTPROG} > "$TMPDIR/record.txt" 2>&1 perf script -i "$TMPDIR/perf.data" --fields brstacksym > "$TMPDIR/perf.script"
# example of branch entries: # brstack_foo+0x14/brstack_bar+0x40/P/-/-/0/CALL
expected=( "^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/IND_CALL/.*$" "^brstack_foo\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$" "^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/CALL/.*$" "^brstack_bench\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$" "^brstack_bar\+[^ ]*/brstack_foo\+[^ ]*/RET/.*$" "^brstack_foo\+[^ ]*/brstack_bench\+[^ ]*/RET/.*$" "^brstack_bench\+[^ ]*/brstack_bench\+[^ ]*/COND/.*$" "^brstack\+[^ ]*/brstack\+[^ ]*/UNCOND/.*$" ) for x in "${expected[@]}" do check_branches "$x" done
# Dump addresses only this time perf script -i "$TMPDIR/perf.data" --fields brstack | \ tr ' ' '\n' > "$TMPDIR/perf.script"
# There should be no kernel addresses in the target with the u option. local regex="0x[89a-f][0-9a-f]{15}" if has_kaslr_bug; then # If the system has a kaslr bug that may leak kernel addresses # in the source of something like an ERET/SYSRET. Make the regex # more specific and just check the target address is in user # code. regex="^0x[0-9a-f]{0,16}/0x[89a-f][0-9a-f]{15}/" fi if grep -q -E -m1 "$regex" $TMPDIR/perf.script; then echo "Testing user branch stack sampling [Failed kernel address found in user mode]" err=1 fi # some branch types are still not being tested: # IND COND_CALL COND_RET SYSRET SERROR NO_TX if [ $err -eq 0 ]; then echo "Testing user branch stack sampling [Passed]" err=$start_err else echo "Testing user branch stack sampling [Failed]" fi}
test_trap_eret_branches() { echo "Testing trap & eret branches"
if ! is_arm64; then echo "Testing trap & eret branches [Skipped not arm64]" return fi start_err=$err err=0 perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u,k -- \ perf test -w traploop 1000 > "$TMPDIR/record.txt" 2>&1 perf script -i $TMPDIR/perf.data --fields brstacksym | \ tr ' ' '\n' > $TMPDIR/perf.script
# BRBINF<n>.TYPE == TRAP are mapped to PERF_BR_IRQ by the BRBE driver check_branches "^trap_bench\+[^ ]+/[^ ]/IRQ/" check_branches "^[^ ]+/trap_bench\+[^ ]+/ERET/" if [ $err -eq 0 ]; then echo "Testing trap & eret branches [Passed]" err=$start_err else echo "Testing trap & eret branches [Failed]" fi}
test_kernel_branches() { echo "Testing kernel branch sampling"
if ! perf record --branch-filter any,k -o- -- true > "$TMPDIR/record.txt" 2>&1; then echo "Testing that k option [Skipped not enough privileges]" return fi start_err=$err err=0 perf record -o $TMPDIR/perf.data --branch-filter any,k -- \ perf bench syscall basic --loop 1000 > "$TMPDIR/record.txt" 2>&1 perf script -i $TMPDIR/perf.data --fields brstack | \ tr ' ' '\n' > $TMPDIR/perf.script
# Example of branch entries: # "0xffffffff93bda241/0xffffffff93bda20f/M/-/-/..." # Source addresses come first in user or kernel code. Next is the target # address that must be in the kernel.
# Look for source addresses with top bit set if ! grep -q -E -m1 "^0x[89a-f][0-9a-f]{15}" $TMPDIR/perf.script; then echo "Testing kernel branch sampling [Failed kernel branches missing]" err=1 fi # Look for no target addresses without top bit set if grep -q -E -m1 "^0x[0-9a-f]{0,16}/0x[0-7][0-9a-f]{1,15}/" $TMPDIR/perf.script; then echo "Testing kernel branch sampling [Failed user branches found]" err=1 fi if [ $err -eq 0 ]; then echo "Testing kernel branch sampling [Passed]" err=$start_err else echo "Testing kernel branch sampling [Failed]" fi}
# first argument <arg0> is the argument passed to "--branch-stack <arg0>,save_type,u"# second argument are the expected branch types for the given filtertest_filter() { test_filter_filter=$1 test_filter_expect=$2
echo "Testing branch stack filtering permutation ($test_filter_filter,$test_filter_expect)" perf record -o "$TMPDIR/perf.data" --branch-filter "$test_filter_filter,save_type,u" -- \ ${TESTPROG} > "$TMPDIR/record.txt" 2>&1 perf script -i "$TMPDIR/perf.data" --fields brstack > "$TMPDIR/perf.script"
# fail if we find any branch type that doesn't match any of the expected ones # also consider UNKNOWN branch types (-) if [ ! -s "$TMPDIR/perf.script" ] then echo "Testing branch stack filtering [Failed empty script output]" err=1 return fi # Look for lines not matching test_filter_expect ignoring issues caused # by empty output tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep '.' | \ grep -E -vm1 "^[^ ]*/($test_filter_expect|-|( *))/.*$" \ > "$TMPDIR/perf.script-filtered" || true if [ -s "$TMPDIR/perf.script-filtered" ] then echo "Testing branch stack filtering [Failed unexpected branch filter]" cat "$TMPDIR/perf.script" err=1 return fi echo "Testing branch stack filtering [Passed]"}
test_syscall() { echo "Testing syscalls" # skip if perf doesn't have enough privileges if ! perf record --branch-filter any,k -o- -- true > "$TMPDIR/record.txt" 2>&1; then echo "Testing syscalls [Skipped: not enough privileges]" return fi start_err=$err err=0 perf record -o $TMPDIR/perf.data --branch-filter \ any_call,save_type,u,k -c 10007 -- \ perf bench syscall basic --loop 8000 > "$TMPDIR/record.txt" 2>&1 perf script -i $TMPDIR/perf.data --fields brstacksym | \ tr ' ' '\n' > $TMPDIR/perf.script
check_branches "getppid[^ ]*/SYSCALL/"
if [ $err -eq 0 ]; then echo "Testing syscalls [Passed]" err=$start_err else echo "Testing syscalls [Failed]" fi}set -e
test_user_branchestest_syscalltest_kernel_branchestest_trap_eret_branches
any_call="CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"
if is_arm64; then any_call="$any_call|FAULT_DATA|FAULT_INST"fi
test_filter "any_call" "$any_call"test_filter "call" "CALL|SYSCALL"test_filter "cond" "COND"test_filter "any_ret" "RET|COND_RET|SYSRET|ERET"
test_filter "call,cond" "CALL|SYSCALL|COND"test_filter "any_call,cond" "$any_call|COND"test_filter "any_call,cond,any_ret" "$any_call|COND|RET|COND_RET"
cleanupexit $err