1#!/bin/bash
2# Check branch stack sampling
3
4# SPDX-License-Identifier: GPL-2.0
5# German Gomez <german.gomez@arm.com>, 2022
6
7shelldir=$(dirname "$0")
8# shellcheck source=lib/perf_has_symbol.sh
9. "${shelldir}"/lib/perf_has_symbol.sh
10
11# skip the test if the hardware doesn't support branch stack sampling
12# and if the architecture doesn't support filter types: any,save_type,u
13if ! perf record -o- --no-buildid --branch-filter any,save_type,u -- true > /dev/null 2>&1 ; then
14	echo "skip: system doesn't support filter types: any,save_type,u"
15	exit 2
16fi
17
18skip_test_missing_symbol brstack_bench
19
20err=0
21TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)
22TESTPROG="perf test -w brstack"
23
24cleanup() {
25	rm -rf $TMPDIR
26	trap - EXIT TERM INT
27}
28
29trap_cleanup() {
30	set +e
31	echo "Unexpected signal in ${FUNCNAME[1]}"
32	cleanup
33	exit 1
34}
35trap trap_cleanup EXIT TERM INT
36
37test_user_branches() {
38	echo "Testing user branch stack sampling"
39
40	perf record -o "$TMPDIR/perf.data" --branch-filter any,save_type,u -- ${TESTPROG} > "$TMPDIR/record.txt" 2>&1
41	perf script -i "$TMPDIR/perf.data" --fields brstacksym > "$TMPDIR/perf.script"
42
43	# example of branch entries:
44	# 	brstack_foo+0x14/brstack_bar+0x40/P/-/-/0/CALL
45
46	expected=(
47		"^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/IND_CALL/.*$"
48		"^brstack_foo\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$"
49		"^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/CALL/.*$"
50		"^brstack_bench\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$"
51		"^brstack_bar\+[^ ]*/brstack_foo\+[^ ]*/RET/.*$"
52		"^brstack_foo\+[^ ]*/brstack_bench\+[^ ]*/RET/.*$"
53		"^brstack_bench\+[^ ]*/brstack_bench\+[^ ]*/COND/.*$"
54		"^brstack\+[^ ]*/brstack\+[^ ]*/UNCOND/.*$"
55	)
56	for x in "${expected[@]}"
57	do
58		if ! tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep -E -m1 -q "$x"
59		then
60			echo "Branches missing $x"
61			err=1
62		fi
63	done
64	# some branch types are still not being tested:
65	# IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX
66}
67
68# first argument <arg0> is the argument passed to "--branch-stack <arg0>,save_type,u"
69# second argument are the expected branch types for the given filter
70test_filter() {
71	test_filter_filter=$1
72	test_filter_expect=$2
73
74	echo "Testing branch stack filtering permutation ($test_filter_filter,$test_filter_expect)"
75	perf record -o "$TMPDIR/perf.data" --branch-filter "$test_filter_filter,save_type,u" -- ${TESTPROG}  > "$TMPDIR/record.txt" 2>&1
76	perf script -i "$TMPDIR/perf.data" --fields brstack > "$TMPDIR/perf.script"
77
78	# fail if we find any branch type that doesn't match any of the expected ones
79	# also consider UNKNOWN branch types (-)
80	if [ ! -s "$TMPDIR/perf.script" ]
81	then
82		echo "Empty script output"
83		err=1
84		return
85	fi
86	# Look for lines not matching test_filter_expect ignoring issues caused
87	# by empty output
88	tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep '.' | \
89	  grep -E -vm1 "^[^ ]*/($test_filter_expect|-|( *))/.*$" \
90	  > "$TMPDIR/perf.script-filtered" || true
91	if [ -s "$TMPDIR/perf.script-filtered" ]
92	then
93		echo "Unexpected branch filter in script output"
94		cat "$TMPDIR/perf.script"
95		err=1
96		return
97	fi
98}
99
100set -e
101
102test_user_branches
103
104test_filter "any_call"	"CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"
105test_filter "call"	"CALL|SYSCALL"
106test_filter "cond"	"COND"
107test_filter "any_ret"	"RET|COND_RET|SYSRET|ERET"
108
109test_filter "call,cond"		"CALL|SYSCALL|COND"
110test_filter "any_call,cond"		"CALL|IND_CALL|COND_CALL|IRQ|SYSCALL|COND"
111test_filter "cond,any_call,any_ret"	"COND|CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|RET|COND_RET|SYSRET|ERET"
112
113cleanup
114exit $err
115