#!/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 ${FUNCNAME[1]}"	cleanup	exit 1}trap trap_cleanup EXIT TERM INT test_user_branches() {	echo "Testing user branch stack sampling" 	perf record -o "$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 "${expected[@]}"	do		if ! tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep -E -m1 -q "$x"		then			echo "Branches missing $x"			err=1		fi	done	# some branch types are still not being tested:	# IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX} # 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 "$TMPDIR/perf.script" ]	then		echo "Empty script output"		err=1		return	fi	# Look for lines not matching test_filter_expect ignoring issues caused	# by empty output	tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep '.' | \	  grep -E -vm1 "^[^ ]*/($test_filter_expect|-|( *))/.*$" \	  > "$TMPDIR/perf.script-filtered" || true	if [ -s "$TMPDIR/perf.script-filtered" ]	then		echo "Unexpected branch filter in script output"		cat "$TMPDIR/perf.script"		err=1		return	fi} set -e test_user_branches test_filter "any_call"	"CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"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"		"CALL|IND_CALL|COND_CALL|IRQ|SYSCALL|COND"test_filter "cond,any_call,any_ret"	"COND|CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|RET|COND_RET|SYSRET|ERET" cleanupexit $err