1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0
3
4SYSFS=
5# Kselftest framework requirement - SKIP code is 4.
6ksft_skip=4
7retval=0
8
9prerequisite()
10{
11	msg="skip all tests:"
12
13	if [ $UID != 0 ]; then
14		echo $msg must be run as root >&2
15		exit $ksft_skip
16	fi
17
18	taskset -p 01 $$
19
20	SYSFS=`mount -t sysfs | head -1 | awk '{ print $3 }'`
21
22	if [ ! -d "$SYSFS" ]; then
23		echo $msg sysfs is not mounted >&2
24		exit $ksft_skip
25	fi
26
27	if ! ls $SYSFS/devices/system/cpu/cpu* > /dev/null 2>&1; then
28		echo $msg cpu hotplug is not supported >&2
29		exit $ksft_skip
30	fi
31
32	echo "CPU online/offline summary:"
33	online_cpus=`cat $SYSFS/devices/system/cpu/online`
34	online_max=${online_cpus##*-}
35
36	if [[ "$online_cpus" = "$online_max" ]]; then
37		echo "$msg: since there is only one cpu: $online_cpus"
38		exit $ksft_skip
39	fi
40
41	present_cpus=`cat $SYSFS/devices/system/cpu/present`
42	present_max=${present_cpus##*-}
43	echo "present_cpus = $present_cpus present_max = $present_max"
44
45	echo -e "\t Cpus in online state: $online_cpus"
46
47	offline_cpus=`cat $SYSFS/devices/system/cpu/offline`
48	if [[ "a$offline_cpus" = "a" ]]; then
49		offline_cpus=0
50	else
51		offline_max=${offline_cpus##*-}
52	fi
53	echo -e "\t Cpus in offline state: $offline_cpus"
54}
55
56#
57# list all hot-pluggable CPUs
58#
59hotpluggable_cpus()
60{
61	local state=${1:-.\*}
62
63	for cpu in $SYSFS/devices/system/cpu/cpu*; do
64		if [ -f $cpu/online ] && grep -q $state $cpu/online; then
65			echo ${cpu##/*/cpu}
66		fi
67	done
68}
69
70hotplaggable_offline_cpus()
71{
72	hotpluggable_cpus 0
73}
74
75hotpluggable_online_cpus()
76{
77	hotpluggable_cpus 1
78}
79
80cpu_is_online()
81{
82	grep -q 1 $SYSFS/devices/system/cpu/cpu$1/online
83}
84
85cpu_is_offline()
86{
87	grep -q 0 $SYSFS/devices/system/cpu/cpu$1/online
88}
89
90online_cpu()
91{
92	echo 1 > $SYSFS/devices/system/cpu/cpu$1/online
93}
94
95offline_cpu()
96{
97	echo 0 > $SYSFS/devices/system/cpu/cpu$1/online
98}
99
100online_cpu_expect_success()
101{
102	local cpu=$1
103
104	if ! online_cpu $cpu; then
105		echo $FUNCNAME $cpu: unexpected fail >&2
106		retval=1
107	elif ! cpu_is_online $cpu; then
108		echo $FUNCNAME $cpu: unexpected offline >&2
109		retval=1
110	fi
111}
112
113online_cpu_expect_fail()
114{
115	local cpu=$1
116
117	if online_cpu $cpu 2> /dev/null; then
118		echo $FUNCNAME $cpu: unexpected success >&2
119		retval=1
120	elif ! cpu_is_offline $cpu; then
121		echo $FUNCNAME $cpu: unexpected online >&2
122		retval=1
123	fi
124}
125
126offline_cpu_expect_success()
127{
128	local cpu=$1
129
130	if ! offline_cpu $cpu; then
131		echo $FUNCNAME $cpu: unexpected fail >&2
132		retval=1
133	elif ! cpu_is_offline $cpu; then
134		echo $FUNCNAME $cpu: unexpected offline >&2
135		retval=1
136	fi
137}
138
139offline_cpu_expect_fail()
140{
141	local cpu=$1
142
143	if offline_cpu $cpu 2> /dev/null; then
144		echo $FUNCNAME $cpu: unexpected success >&2
145		retval=1
146	elif ! cpu_is_online $cpu; then
147		echo $FUNCNAME $cpu: unexpected offline >&2
148		retval=1
149	fi
150}
151
152online_all_hot_pluggable_cpus()
153{
154	for cpu in `hotplaggable_offline_cpus`; do
155		online_cpu_expect_success $cpu
156	done
157}
158
159offline_all_hot_pluggable_cpus()
160{
161	local reserve_cpu=$online_max
162	for cpu in `hotpluggable_online_cpus`; do
163		# Reserve one cpu oneline at least.
164		if [ $cpu -eq $reserve_cpu ];then
165			continue
166		fi
167		offline_cpu_expect_success $cpu
168	done
169}
170
171allcpus=0
172online_cpus=0
173online_max=0
174offline_cpus=0
175offline_max=0
176present_cpus=0
177present_max=0
178
179while getopts ah opt; do
180	case $opt in
181	a)
182		allcpus=1
183		;;
184	h)
185		echo "Usage $0 [ -a ]"
186		echo -e "\t default offline one cpu"
187		echo -e "\t run with -a option to offline all cpus"
188		exit
189		;;
190	esac
191done
192
193prerequisite
194
195#
196# Safe test (default) - offline and online one cpu
197#
198if [ $allcpus -eq 0 ]; then
199	echo "Limited scope test: one hotplug cpu"
200	echo -e "\t (leaves cpu in the original state):"
201	echo -e "\t online to offline to online: cpu $online_max"
202	offline_cpu_expect_success $online_max
203	online_cpu_expect_success $online_max
204
205	if [[ $offline_cpus -gt 0 ]]; then
206		echo -e "\t online to offline to online: cpu $present_max"
207		online_cpu_expect_success $present_max
208		offline_cpu_expect_success $present_max
209		online_cpu $present_max
210	fi
211	exit $retval
212else
213	echo "Full scope test: all hotplug cpus"
214	echo -e "\t online all offline cpus"
215	echo -e "\t offline all online cpus"
216	echo -e "\t online all offline cpus"
217fi
218
219online_all_hot_pluggable_cpus
220
221offline_all_hot_pluggable_cpus
222
223online_all_hot_pluggable_cpus
224
225exit $retval
226