1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/*
* Kernel module for testing static keys.
*
* Copyright 2015 Akamai Technologies Inc. All Rights Reserved
*
* Authors:
* Jason Baron <jbaron@akamai.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/jump_label.h>
/* old keys */
struct static_key old_true_key = STATIC_KEY_INIT_TRUE;
struct static_key old_false_key = STATIC_KEY_INIT_FALSE;
/* new api */
DEFINE_STATIC_KEY_TRUE(true_key);
DEFINE_STATIC_KEY_FALSE(false_key);
/* external */
extern struct static_key base_old_true_key;
extern struct static_key base_inv_old_true_key;
extern struct static_key base_old_false_key;
extern struct static_key base_inv_old_false_key;
/* new api */
extern struct static_key_true base_true_key;
extern struct static_key_true base_inv_true_key;
extern struct static_key_false base_false_key;
extern struct static_key_false base_inv_false_key;
struct test_key {
bool init_state;
struct static_key *key;
bool (*test_key)(void);
};
#define test_key_func(key, branch) \
({bool func(void) { return branch(key); } func; })
static void invert_key(struct static_key *key)
{
if (static_key_enabled(key))
static_key_disable(key);
else
static_key_enable(key);
}
static void invert_keys(struct test_key *keys, int size)
{
struct static_key *previous = NULL;
int i;
for (i = 0; i < size; i++) {
if (previous != keys[i].key) {
invert_key(keys[i].key);
previous = keys[i].key;
}
}
}
int verify_keys(struct test_key *keys, int size, bool invert)
{
int i;
bool ret, init;
for (i = 0; i < size; i++) {
ret = static_key_enabled(keys[i].key);
init = keys[i].init_state;
if (ret != (invert ? !init : init))
return -EINVAL;
ret = keys[i].test_key();
if (static_key_enabled(keys[i].key)) {
if (!ret)
return -EINVAL;
} else {
if (ret)
return -EINVAL;
}
}
return 0;
}
static int __init test_static_key_init(void)
{
int ret;
int size;
struct test_key static_key_tests[] = {
/* internal keys - old keys */
{
.init_state = true,
.key = &old_true_key,
.test_key = test_key_func(&old_true_key, static_key_true),
},
{
.init_state = false,
.key = &old_false_key,
.test_key = test_key_func(&old_false_key, static_key_false),
},
/* internal keys - new keys */
{
.init_state = true,
.key = &true_key.key,
.test_key = test_key_func(&true_key, static_branch_likely),
},
{
.init_state = true,
.key = &true_key.key,
.test_key = test_key_func(&true_key, static_branch_unlikely),
},
{
.init_state = false,
.key = &false_key.key,
.test_key = test_key_func(&false_key, static_branch_likely),
},
{
.init_state = false,
.key = &false_key.key,
.test_key = test_key_func(&false_key, static_branch_unlikely),
},
/* external keys - old keys */
{
.init_state = true,
.key = &base_old_true_key,
.test_key = test_key_func(&base_old_true_key, static_key_true),
},
{
.init_state = false,
.key = &base_inv_old_true_key,
.test_key = test_key_func(&base_inv_old_true_key, static_key_true),
},
{
.init_state = false,
.key = &base_old_false_key,
.test_key = test_key_func(&base_old_false_key, static_key_false),
},
{
.init_state = true,
.key = &base_inv_old_false_key,
.test_key = test_key_func(&base_inv_old_false_key, static_key_false),
},
/* external keys - new keys */
{
.init_state = true,
.key = &base_true_key.key,
.test_key = test_key_func(&base_true_key, static_branch_likely),
},
{
.init_state = true,
.key = &base_true_key.key,
.test_key = test_key_func(&base_true_key, static_branch_unlikely),
},
{
.init_state = false,
.key = &base_inv_true_key.key,
.test_key = test_key_func(&base_inv_true_key, static_branch_likely),
},
{
.init_state = false,
.key = &base_inv_true_key.key,
.test_key = test_key_func(&base_inv_true_key, static_branch_unlikely),
},
{
.init_state = false,
.key = &base_false_key.key,
.test_key = test_key_func(&base_false_key, static_branch_likely),
},
{
.init_state = false,
.key = &base_false_key.key,
.test_key = test_key_func(&base_false_key, static_branch_unlikely),
},
{
.init_state = true,
.key = &base_inv_false_key.key,
.test_key = test_key_func(&base_inv_false_key, static_branch_likely),
},
{
.init_state = true,
.key = &base_inv_false_key.key,
.test_key = test_key_func(&base_inv_false_key, static_branch_unlikely),
},
};
size = ARRAY_SIZE(static_key_tests);
ret = verify_keys(static_key_tests, size, false);
if (ret)
goto out;
invert_keys(static_key_tests, size);
ret = verify_keys(static_key_tests, size, true);
if (ret)
goto out;
invert_keys(static_key_tests, size);
ret = verify_keys(static_key_tests, size, false);
if (ret)
goto out;
return 0;
out:
return ret;
}
static void __exit test_static_key_exit(void)
{
}
module_init(test_static_key_init);
module_exit(test_static_key_exit);
MODULE_AUTHOR("Jason Baron <jbaron@akamai.com>");
MODULE_LICENSE("GPL");
|
