1#!/bin/sh
2# Check branch stack sampling
3
4# SPDX-License-Identifier: GPL-2.0
5# German Gomez <german.gomez@arm.com>, 2022
6
7# skip the test if the hardware doesn't support branch stack sampling
8# and if the architecture doesn't support filter types: any,save_type,u
9if ! perf record -o- --no-buildid --branch-filter any,save_type,u -- true > /dev/null 2>&1 ; then
10	echo "skip: system doesn't support filter types: any,save_type,u"
11	exit 2
12fi
13
14TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)
15TESTPROG="perf test -w brstack"
16
17cleanup() {
18	rm -rf $TMPDIR
19}
20
21trap cleanup EXIT TERM INT
22
23test_user_branches() {
24	echo "Testing user branch stack sampling"
25
26	perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u -- ${TESTPROG} > /dev/null 2>&1
27	perf script -i $TMPDIR/perf.data --fields brstacksym | xargs -n1 > $TMPDIR/perf.script
28
29	# example of branch entries:
30	# 	brstack_foo+0x14/brstack_bar+0x40/P/-/-/0/CALL
31
32	set -x
33	grep -E -m1 "^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/IND_CALL/.*$"	$TMPDIR/perf.script
34	grep -E -m1 "^brstack_foo\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$"	$TMPDIR/perf.script
35	grep -E -m1 "^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/CALL/.*$"	$TMPDIR/perf.script
36	grep -E -m1 "^brstack_bench\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$"	$TMPDIR/perf.script
37	grep -E -m1 "^brstack_bar\+[^ ]*/brstack_foo\+[^ ]*/RET/.*$"		$TMPDIR/perf.script
38	grep -E -m1 "^brstack_foo\+[^ ]*/brstack_bench\+[^ ]*/RET/.*$"	$TMPDIR/perf.script
39	grep -E -m1 "^brstack_bench\+[^ ]*/brstack_bench\+[^ ]*/COND/.*$"	$TMPDIR/perf.script
40	grep -E -m1 "^brstack\+[^ ]*/brstack\+[^ ]*/UNCOND/.*$"		$TMPDIR/perf.script
41	set +x
42
43	# some branch types are still not being tested:
44	# IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX
45}
46
47# first argument <arg0> is the argument passed to "--branch-stack <arg0>,save_type,u"
48# second argument are the expected branch types for the given filter
49test_filter() {
50	test_filter_filter=$1
51	test_filter_expect=$2
52
53	echo "Testing branch stack filtering permutation ($test_filter_filter,$test_filter_expect)"
54
55	perf record -o $TMPDIR/perf.data --branch-filter $test_filter_filter,save_type,u -- ${TESTPROG} > /dev/null 2>&1
56	perf script -i $TMPDIR/perf.data --fields brstack | xargs -n1 > $TMPDIR/perf.script
57
58	# fail if we find any branch type that doesn't match any of the expected ones
59	# also consider UNKNOWN branch types (-)
60	if grep -E -vm1 "^[^ ]*/($test_filter_expect|-|( *))/.*$" $TMPDIR/perf.script; then
61		return 1
62	fi
63}
64
65set -e
66
67test_user_branches
68
69test_filter "any_call"	"CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"
70test_filter "call"	"CALL|SYSCALL"
71test_filter "cond"	"COND"
72test_filter "any_ret"	"RET|COND_RET|SYSRET|ERET"
73
74test_filter "call,cond"		"CALL|SYSCALL|COND"
75test_filter "any_call,cond"		"CALL|IND_CALL|COND_CALL|IRQ|SYSCALL|COND"
76test_filter "cond,any_call,any_ret"	"COND|CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|RET|COND_RET|SYSRET|ERET"
77