1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2014 Google, Inc.
4 */
5
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8 #include <linux/delay.h>
9 #include <linux/init.h>
10 #include <linux/hrtimer.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/time.h>
14 #include <linux/numa.h>
15 #include <linux/nodemask.h>
16 #include <linux/topology.h>
17
18 #define TEST_PROBE_DELAY (5 * 1000) /* 5 sec */
19 #define TEST_PROBE_THRESHOLD (TEST_PROBE_DELAY / 2)
20
21 static atomic_t warnings, errors, timeout, async_completed;
22
test_probe(struct platform_device * pdev)23 static int test_probe(struct platform_device *pdev)
24 {
25 struct device *dev = &pdev->dev;
26
27 /*
28 * Determine if we have hit the "timeout" limit for the test if we
29 * have then report it as an error, otherwise we wil sleep for the
30 * required amount of time and then report completion.
31 */
32 if (atomic_read(&timeout)) {
33 dev_err(dev, "async probe took too long\n");
34 atomic_inc(&errors);
35 } else {
36 dev_dbg(&pdev->dev, "sleeping for %d msecs in probe\n",
37 TEST_PROBE_DELAY);
38 msleep(TEST_PROBE_DELAY);
39 dev_dbg(&pdev->dev, "done sleeping\n");
40 }
41
42 /*
43 * Report NUMA mismatch if device node is set and we are not
44 * performing an async init on that node.
45 */
46 if (dev->driver->probe_type == PROBE_PREFER_ASYNCHRONOUS) {
47 if (IS_ENABLED(CONFIG_NUMA) &&
48 dev_to_node(dev) != numa_node_id()) {
49 dev_warn(dev, "NUMA node mismatch %d != %d\n",
50 dev_to_node(dev), numa_node_id());
51 atomic_inc(&warnings);
52 }
53
54 atomic_inc(&async_completed);
55 }
56
57 return 0;
58 }
59
60 static struct platform_driver async_driver = {
61 .driver = {
62 .name = "test_async_driver",
63 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
64 },
65 .probe = test_probe,
66 };
67
68 static struct platform_driver sync_driver = {
69 .driver = {
70 .name = "test_sync_driver",
71 .probe_type = PROBE_FORCE_SYNCHRONOUS,
72 },
73 .probe = test_probe,
74 };
75
76 static struct platform_device *async_dev[NR_CPUS * 2];
77 static struct platform_device *sync_dev[2];
78
79 static struct platform_device *
test_platform_device_register_node(char * name,int id,int nid)80 test_platform_device_register_node(char *name, int id, int nid)
81 {
82 struct platform_device *pdev;
83 int ret;
84
85 pdev = platform_device_alloc(name, id);
86 if (!pdev)
87 return NULL;
88
89 if (nid != NUMA_NO_NODE)
90 set_dev_node(&pdev->dev, nid);
91
92 ret = platform_device_add(pdev);
93 if (ret) {
94 platform_device_put(pdev);
95 return ERR_PTR(ret);
96 }
97
98 return pdev;
99
100 }
101
test_async_probe_init(void)102 static int __init test_async_probe_init(void)
103 {
104 struct platform_device **pdev = NULL;
105 int async_id = 0, sync_id = 0;
106 unsigned long long duration;
107 ktime_t calltime, delta;
108 int err, nid, cpu;
109
110 pr_info("registering first set of asynchronous devices...\n");
111
112 for_each_online_cpu(cpu) {
113 nid = cpu_to_node(cpu);
114 pdev = &async_dev[async_id];
115 *pdev = test_platform_device_register_node("test_async_driver",
116 async_id,
117 nid);
118 if (IS_ERR(*pdev)) {
119 err = PTR_ERR(*pdev);
120 *pdev = NULL;
121 pr_err("failed to create async_dev: %d\n", err);
122 goto err_unregister_async_devs;
123 }
124
125 async_id++;
126 }
127
128 pr_info("registering asynchronous driver...\n");
129 calltime = ktime_get();
130 err = platform_driver_register(&async_driver);
131 if (err) {
132 pr_err("Failed to register async_driver: %d\n", err);
133 goto err_unregister_async_devs;
134 }
135
136 delta = ktime_sub(ktime_get(), calltime);
137 duration = (unsigned long long) ktime_to_ms(delta);
138 pr_info("registration took %lld msecs\n", duration);
139 if (duration > TEST_PROBE_THRESHOLD) {
140 pr_err("test failed: probe took too long\n");
141 err = -ETIMEDOUT;
142 goto err_unregister_async_driver;
143 }
144
145 pr_info("registering second set of asynchronous devices...\n");
146 calltime = ktime_get();
147 for_each_online_cpu(cpu) {
148 nid = cpu_to_node(cpu);
149 pdev = &sync_dev[sync_id];
150
151 *pdev = test_platform_device_register_node("test_async_driver",
152 async_id,
153 nid);
154 if (IS_ERR(*pdev)) {
155 err = PTR_ERR(*pdev);
156 *pdev = NULL;
157 pr_err("failed to create async_dev: %d\n", err);
158 goto err_unregister_async_driver;
159 }
160
161 async_id++;
162 }
163
164 delta = ktime_sub(ktime_get(), calltime);
165 duration = (unsigned long long) ktime_to_ms(delta);
166 dev_info(&(*pdev)->dev,
167 "registration took %lld msecs\n", duration);
168 if (duration > TEST_PROBE_THRESHOLD) {
169 dev_err(&(*pdev)->dev,
170 "test failed: probe took too long\n");
171 err = -ETIMEDOUT;
172 goto err_unregister_async_driver;
173 }
174
175
176 pr_info("registering first synchronous device...\n");
177 nid = cpu_to_node(cpu);
178 pdev = &sync_dev[sync_id];
179
180 *pdev = test_platform_device_register_node("test_sync_driver",
181 sync_id,
182 NUMA_NO_NODE);
183 if (IS_ERR(*pdev)) {
184 err = PTR_ERR(*pdev);
185 *pdev = NULL;
186 pr_err("failed to create sync_dev: %d\n", err);
187 goto err_unregister_async_driver;
188 }
189
190 sync_id++;
191
192 pr_info("registering synchronous driver...\n");
193 calltime = ktime_get();
194 err = platform_driver_register(&sync_driver);
195 if (err) {
196 pr_err("Failed to register async_driver: %d\n", err);
197 goto err_unregister_sync_devs;
198 }
199
200 delta = ktime_sub(ktime_get(), calltime);
201 duration = (unsigned long long) ktime_to_ms(delta);
202 pr_info("registration took %lld msecs\n", duration);
203 if (duration < TEST_PROBE_THRESHOLD) {
204 dev_err(&(*pdev)->dev,
205 "test failed: probe was too quick\n");
206 err = -ETIMEDOUT;
207 goto err_unregister_sync_driver;
208 }
209
210 pr_info("registering second synchronous device...\n");
211 pdev = &sync_dev[sync_id];
212 calltime = ktime_get();
213
214 *pdev = test_platform_device_register_node("test_sync_driver",
215 sync_id,
216 NUMA_NO_NODE);
217 if (IS_ERR(*pdev)) {
218 err = PTR_ERR(*pdev);
219 *pdev = NULL;
220 pr_err("failed to create sync_dev: %d\n", err);
221 goto err_unregister_sync_driver;
222 }
223
224 sync_id++;
225
226 delta = ktime_sub(ktime_get(), calltime);
227 duration = (unsigned long long) ktime_to_ms(delta);
228 dev_info(&(*pdev)->dev,
229 "registration took %lld msecs\n", duration);
230 if (duration < TEST_PROBE_THRESHOLD) {
231 dev_err(&(*pdev)->dev,
232 "test failed: probe was too quick\n");
233 err = -ETIMEDOUT;
234 goto err_unregister_sync_driver;
235 }
236
237 /*
238 * The async events should have completed while we were taking care
239 * of the synchronous events. We will now terminate any outstanding
240 * asynchronous probe calls remaining by forcing timeout and remove
241 * the driver before we return which should force the flush of the
242 * pending asynchronous probe calls.
243 *
244 * Otherwise if they completed without errors or warnings then
245 * report successful completion.
246 */
247 if (atomic_read(&async_completed) != async_id) {
248 pr_err("async events still pending, forcing timeout\n");
249 atomic_inc(&timeout);
250 err = -ETIMEDOUT;
251 } else if (!atomic_read(&errors) && !atomic_read(&warnings)) {
252 pr_info("completed successfully\n");
253 return 0;
254 }
255
256 err_unregister_sync_driver:
257 platform_driver_unregister(&sync_driver);
258 err_unregister_sync_devs:
259 while (sync_id--)
260 platform_device_unregister(sync_dev[sync_id]);
261 err_unregister_async_driver:
262 platform_driver_unregister(&async_driver);
263 err_unregister_async_devs:
264 while (async_id--)
265 platform_device_unregister(async_dev[async_id]);
266
267 /*
268 * If err is already set then count that as an additional error for
269 * the test. Otherwise we will report an invalid argument error and
270 * not count that as we should have reached here as a result of
271 * errors or warnings being reported by the probe routine.
272 */
273 if (err)
274 atomic_inc(&errors);
275 else
276 err = -EINVAL;
277
278 pr_err("Test failed with %d errors and %d warnings\n",
279 atomic_read(&errors), atomic_read(&warnings));
280
281 return err;
282 }
283 module_init(test_async_probe_init);
284
test_async_probe_exit(void)285 static void __exit test_async_probe_exit(void)
286 {
287 int id = 2;
288
289 platform_driver_unregister(&async_driver);
290 platform_driver_unregister(&sync_driver);
291
292 while (id--)
293 platform_device_unregister(sync_dev[id]);
294
295 id = NR_CPUS * 2;
296 while (id--)
297 platform_device_unregister(async_dev[id]);
298 }
299 module_exit(test_async_probe_exit);
300
301 MODULE_DESCRIPTION("Test module for asynchronous driver probing");
302 MODULE_AUTHOR("Dmitry Torokhov <dtor@chromium.org>");
303 MODULE_LICENSE("GPL");
304
