1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0
3
4SYSFS=
5# Kselftest framework requirement - SKIP code is 4.
6ksft_skip=4
7
8prerequisite()
9{
10	msg="skip all tests:"
11
12	if [ $UID != 0 ]; then
13		echo $msg must be run as root >&2
14		exit $ksft_skip
15	fi
16
17	taskset -p 01 $$
18
19	SYSFS=`mount -t sysfs | head -1 | awk '{ print $3 }'`
20
21	if [ ! -d "$SYSFS" ]; then
22		echo $msg sysfs is not mounted >&2
23		exit $ksft_skip
24	fi
25
26	if ! ls $SYSFS/devices/system/cpu/cpu* > /dev/null 2>&1; then
27		echo $msg cpu hotplug is not supported >&2
28		exit $ksft_skip
29	fi
30
31	echo "CPU online/offline summary:"
32	online_cpus=`cat $SYSFS/devices/system/cpu/online`
33	online_max=${online_cpus##*-}
34
35	if [[ "$online_cpus" = "$online_max" ]]; then
36		echo "$msg: since there is only one cpu: $online_cpus"
37		exit $ksft_skip
38	fi
39
40	present_cpus=`cat $SYSFS/devices/system/cpu/present`
41	present_max=${present_cpus##*-}
42	echo "present_cpus = $present_cpus present_max = $present_max"
43
44	echo -e "\t Cpus in online state: $online_cpus"
45
46	offline_cpus=`cat $SYSFS/devices/system/cpu/offline`
47	if [[ "a$offline_cpus" = "a" ]]; then
48		offline_cpus=0
49	else
50		offline_max=${offline_cpus##*-}
51	fi
52	echo -e "\t Cpus in offline state: $offline_cpus"
53}
54
55#
56# list all hot-pluggable CPUs
57#
58hotpluggable_cpus()
59{
60	local state=${1:-.\*}
61
62	for cpu in $SYSFS/devices/system/cpu/cpu*; do
63		if [ -f $cpu/online ] && grep -q $state $cpu/online; then
64			echo ${cpu##/*/cpu}
65		fi
66	done
67}
68
69hotplaggable_offline_cpus()
70{
71	hotpluggable_cpus 0
72}
73
74hotpluggable_online_cpus()
75{
76	hotpluggable_cpus 1
77}
78
79cpu_is_online()
80{
81	grep -q 1 $SYSFS/devices/system/cpu/cpu$1/online
82}
83
84cpu_is_offline()
85{
86	grep -q 0 $SYSFS/devices/system/cpu/cpu$1/online
87}
88
89online_cpu()
90{
91	echo 1 > $SYSFS/devices/system/cpu/cpu$1/online
92}
93
94offline_cpu()
95{
96	echo 0 > $SYSFS/devices/system/cpu/cpu$1/online
97}
98
99online_cpu_expect_success()
100{
101	local cpu=$1
102
103	if ! online_cpu $cpu; then
104		echo $FUNCNAME $cpu: unexpected fail >&2
105		exit 1
106	elif ! cpu_is_online $cpu; then
107		echo $FUNCNAME $cpu: unexpected offline >&2
108		exit 1
109	fi
110}
111
112online_cpu_expect_fail()
113{
114	local cpu=$1
115
116	if online_cpu $cpu 2> /dev/null; then
117		echo $FUNCNAME $cpu: unexpected success >&2
118		exit 1
119	elif ! cpu_is_offline $cpu; then
120		echo $FUNCNAME $cpu: unexpected online >&2
121		exit 1
122	fi
123}
124
125offline_cpu_expect_success()
126{
127	local cpu=$1
128
129	if ! offline_cpu $cpu; then
130		echo $FUNCNAME $cpu: unexpected fail >&2
131		exit 1
132	elif ! cpu_is_offline $cpu; then
133		echo $FUNCNAME $cpu: unexpected offline >&2
134		exit 1
135	fi
136}
137
138offline_cpu_expect_fail()
139{
140	local cpu=$1
141
142	if offline_cpu $cpu 2> /dev/null; then
143		echo $FUNCNAME $cpu: unexpected success >&2
144		exit 1
145	elif ! cpu_is_online $cpu; then
146		echo $FUNCNAME $cpu: unexpected offline >&2
147		exit 1
148	fi
149}
150
151error=-12
152allcpus=0
153priority=0
154online_cpus=0
155online_max=0
156offline_cpus=0
157offline_max=0
158present_cpus=0
159present_max=0
160
161while getopts e:ahp: opt; do
162	case $opt in
163	e)
164		error=$OPTARG
165		;;
166	a)
167		allcpus=1
168		;;
169	h)
170		echo "Usage $0 [ -a ] [ -e errno ] [ -p notifier-priority ]"
171		echo -e "\t default offline one cpu"
172		echo -e "\t run with -a option to offline all cpus"
173		exit
174		;;
175	p)
176		priority=$OPTARG
177		;;
178	esac
179done
180
181if ! [ "$error" -ge -4095 -a "$error" -lt 0 ]; then
182	echo "error code must be -4095 <= errno < 0" >&2
183	exit 1
184fi
185
186prerequisite
187
188#
189# Safe test (default) - offline and online one cpu
190#
191if [ $allcpus -eq 0 ]; then
192	echo "Limited scope test: one hotplug cpu"
193	echo -e "\t (leaves cpu in the original state):"
194	echo -e "\t online to offline to online: cpu $online_max"
195	offline_cpu_expect_success $online_max
196	online_cpu_expect_success $online_max
197
198	if [[ $offline_cpus -gt 0 ]]; then
199		echo -e "\t offline to online to offline: cpu $present_max"
200		online_cpu_expect_success $present_max
201		offline_cpu_expect_success $present_max
202		online_cpu $present_max
203	fi
204	exit 0
205else
206	echo "Full scope test: all hotplug cpus"
207	echo -e "\t online all offline cpus"
208	echo -e "\t offline all online cpus"
209	echo -e "\t online all offline cpus"
210fi
211
212#
213# Online all hot-pluggable CPUs
214#
215for cpu in `hotplaggable_offline_cpus`; do
216	online_cpu_expect_success $cpu
217done
218
219#
220# Offline all hot-pluggable CPUs
221#
222for cpu in `hotpluggable_online_cpus`; do
223	offline_cpu_expect_success $cpu
224done
225
226#
227# Online all hot-pluggable CPUs again
228#
229for cpu in `hotplaggable_offline_cpus`; do
230	online_cpu_expect_success $cpu
231done
232
233#
234# Test with cpu notifier error injection
235#
236
237DEBUGFS=`mount -t debugfs | head -1 | awk '{ print $3 }'`
238NOTIFIER_ERR_INJECT_DIR=$DEBUGFS/notifier-error-inject/cpu
239
240prerequisite_extra()
241{
242	msg="skip extra tests:"
243
244	/sbin/modprobe -q -r cpu-notifier-error-inject
245	/sbin/modprobe -q cpu-notifier-error-inject priority=$priority
246
247	if [ ! -d "$DEBUGFS" ]; then
248		echo $msg debugfs is not mounted >&2
249		exit $ksft_skip
250	fi
251
252	if [ ! -d $NOTIFIER_ERR_INJECT_DIR ]; then
253		echo $msg cpu-notifier-error-inject module is not available >&2
254		exit $ksft_skip
255	fi
256}
257
258prerequisite_extra
259
260#
261# Offline all hot-pluggable CPUs
262#
263echo 0 > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_DOWN_PREPARE/error
264for cpu in `hotpluggable_online_cpus`; do
265	offline_cpu_expect_success $cpu
266done
267
268#
269# Test CPU hot-add error handling (offline => online)
270#
271echo $error > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_UP_PREPARE/error
272for cpu in `hotplaggable_offline_cpus`; do
273	online_cpu_expect_fail $cpu
274done
275
276#
277# Online all hot-pluggable CPUs
278#
279echo 0 > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_UP_PREPARE/error
280for cpu in `hotplaggable_offline_cpus`; do
281	online_cpu_expect_success $cpu
282done
283
284#
285# Test CPU hot-remove error handling (online => offline)
286#
287echo $error > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_DOWN_PREPARE/error
288for cpu in `hotpluggable_online_cpus`; do
289	offline_cpu_expect_fail $cpu
290done
291
292echo 0 > $NOTIFIER_ERR_INJECT_DIR/actions/CPU_DOWN_PREPARE/error
293/sbin/modprobe -q -r cpu-notifier-error-inject
294