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0af3fe1e PM |
1 | /* |
2 | * Module-based torture test facility for locking | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, you can access it online at | |
16 | * http://www.gnu.org/licenses/gpl-2.0.html. | |
17 | * | |
18 | * Copyright (C) IBM Corporation, 2014 | |
19 | * | |
095777c4 DB |
20 | * Authors: Paul E. McKenney <paulmck@us.ibm.com> |
21 | * Davidlohr Bueso <dave@stgolabs.net> | |
0af3fe1e PM |
22 | * Based on kernel/rcu/torture.c. |
23 | */ | |
0af3fe1e | 24 | #include <linux/kernel.h> |
0af3fe1e PM |
25 | #include <linux/module.h> |
26 | #include <linux/kthread.h> | |
095777c4 | 27 | #include <linux/sched/rt.h> |
0af3fe1e | 28 | #include <linux/spinlock.h> |
e34191fa | 29 | #include <linux/rwlock.h> |
42ddc75d | 30 | #include <linux/mutex.h> |
c98fed9f | 31 | #include <linux/rwsem.h> |
0af3fe1e PM |
32 | #include <linux/smp.h> |
33 | #include <linux/interrupt.h> | |
34 | #include <linux/sched.h> | |
35 | #include <linux/atomic.h> | |
0af3fe1e | 36 | #include <linux/moduleparam.h> |
0af3fe1e | 37 | #include <linux/delay.h> |
0af3fe1e | 38 | #include <linux/slab.h> |
617783dd | 39 | #include <linux/percpu-rwsem.h> |
0af3fe1e PM |
40 | #include <linux/torture.h> |
41 | ||
42 | MODULE_LICENSE("GPL"); | |
43 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>"); | |
44 | ||
45 | torture_param(int, nwriters_stress, -1, | |
46 | "Number of write-locking stress-test threads"); | |
4f6332c1 DB |
47 | torture_param(int, nreaders_stress, -1, |
48 | "Number of read-locking stress-test threads"); | |
0af3fe1e PM |
49 | torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); |
50 | torture_param(int, onoff_interval, 0, | |
51 | "Time between CPU hotplugs (s), 0=disable"); | |
52 | torture_param(int, shuffle_interval, 3, | |
53 | "Number of jiffies between shuffles, 0=disable"); | |
54 | torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable."); | |
55 | torture_param(int, stat_interval, 60, | |
56 | "Number of seconds between stats printk()s"); | |
57 | torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable"); | |
58 | torture_param(bool, verbose, true, | |
59 | "Enable verbose debugging printk()s"); | |
60 | ||
61 | static char *torture_type = "spin_lock"; | |
62 | module_param(torture_type, charp, 0444); | |
63 | MODULE_PARM_DESC(torture_type, | |
42ddc75d | 64 | "Type of lock to torture (spin_lock, spin_lock_irq, mutex_lock, ...)"); |
0af3fe1e | 65 | |
0af3fe1e PM |
66 | static struct task_struct *stats_task; |
67 | static struct task_struct **writer_tasks; | |
4f6332c1 | 68 | static struct task_struct **reader_tasks; |
0af3fe1e | 69 | |
0af3fe1e | 70 | static bool lock_is_write_held; |
4f6332c1 | 71 | static bool lock_is_read_held; |
0af3fe1e | 72 | |
1e6757a9 DB |
73 | struct lock_stress_stats { |
74 | long n_lock_fail; | |
75 | long n_lock_acquired; | |
0af3fe1e | 76 | }; |
0af3fe1e | 77 | |
5db42981 | 78 | int torture_runnable = IS_ENABLED(MODULE); |
23a8e5c2 DB |
79 | module_param(torture_runnable, int, 0444); |
80 | MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init"); | |
0af3fe1e PM |
81 | |
82 | /* Forward reference. */ | |
83 | static void lock_torture_cleanup(void); | |
84 | ||
85 | /* | |
86 | * Operations vector for selecting different types of tests. | |
87 | */ | |
88 | struct lock_torture_ops { | |
89 | void (*init)(void); | |
90 | int (*writelock)(void); | |
91 | void (*write_delay)(struct torture_random_state *trsp); | |
095777c4 | 92 | void (*task_boost)(struct torture_random_state *trsp); |
0af3fe1e | 93 | void (*writeunlock)(void); |
4f6332c1 DB |
94 | int (*readlock)(void); |
95 | void (*read_delay)(struct torture_random_state *trsp); | |
96 | void (*readunlock)(void); | |
095777c4 DB |
97 | |
98 | unsigned long flags; /* for irq spinlocks */ | |
0af3fe1e PM |
99 | const char *name; |
100 | }; | |
101 | ||
630952c2 DB |
102 | struct lock_torture_cxt { |
103 | int nrealwriters_stress; | |
104 | int nrealreaders_stress; | |
105 | bool debug_lock; | |
106 | atomic_t n_lock_torture_errors; | |
107 | struct lock_torture_ops *cur_ops; | |
108 | struct lock_stress_stats *lwsa; /* writer statistics */ | |
109 | struct lock_stress_stats *lrsa; /* reader statistics */ | |
110 | }; | |
111 | static struct lock_torture_cxt cxt = { 0, 0, false, | |
112 | ATOMIC_INIT(0), | |
113 | NULL, NULL}; | |
0af3fe1e PM |
114 | /* |
115 | * Definitions for lock torture testing. | |
116 | */ | |
117 | ||
e086481b PM |
118 | static int torture_lock_busted_write_lock(void) |
119 | { | |
120 | return 0; /* BUGGY, do not use in real life!!! */ | |
121 | } | |
122 | ||
123 | static void torture_lock_busted_write_delay(struct torture_random_state *trsp) | |
124 | { | |
61d49d2f | 125 | const unsigned long longdelay_ms = 100; |
e086481b PM |
126 | |
127 | /* We want a long delay occasionally to force massive contention. */ | |
128 | if (!(torture_random(trsp) % | |
61d49d2f PM |
129 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
130 | mdelay(longdelay_ms); | |
e086481b | 131 | #ifdef CONFIG_PREEMPT |
630952c2 | 132 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
e086481b PM |
133 | preempt_schedule(); /* Allow test to be preempted. */ |
134 | #endif | |
135 | } | |
136 | ||
137 | static void torture_lock_busted_write_unlock(void) | |
138 | { | |
139 | /* BUGGY, do not use in real life!!! */ | |
140 | } | |
141 | ||
095777c4 DB |
142 | static void torture_boost_dummy(struct torture_random_state *trsp) |
143 | { | |
144 | /* Only rtmutexes care about priority */ | |
145 | } | |
146 | ||
e086481b PM |
147 | static struct lock_torture_ops lock_busted_ops = { |
148 | .writelock = torture_lock_busted_write_lock, | |
149 | .write_delay = torture_lock_busted_write_delay, | |
095777c4 | 150 | .task_boost = torture_boost_dummy, |
e086481b | 151 | .writeunlock = torture_lock_busted_write_unlock, |
4f6332c1 DB |
152 | .readlock = NULL, |
153 | .read_delay = NULL, | |
154 | .readunlock = NULL, | |
e086481b PM |
155 | .name = "lock_busted" |
156 | }; | |
157 | ||
0af3fe1e PM |
158 | static DEFINE_SPINLOCK(torture_spinlock); |
159 | ||
160 | static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock) | |
161 | { | |
162 | spin_lock(&torture_spinlock); | |
163 | return 0; | |
164 | } | |
165 | ||
166 | static void torture_spin_lock_write_delay(struct torture_random_state *trsp) | |
167 | { | |
168 | const unsigned long shortdelay_us = 2; | |
61d49d2f | 169 | const unsigned long longdelay_ms = 100; |
0af3fe1e PM |
170 | |
171 | /* We want a short delay mostly to emulate likely code, and | |
172 | * we want a long delay occasionally to force massive contention. | |
173 | */ | |
174 | if (!(torture_random(trsp) % | |
61d49d2f PM |
175 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
176 | mdelay(longdelay_ms); | |
0af3fe1e | 177 | if (!(torture_random(trsp) % |
630952c2 | 178 | (cxt.nrealwriters_stress * 2 * shortdelay_us))) |
0af3fe1e PM |
179 | udelay(shortdelay_us); |
180 | #ifdef CONFIG_PREEMPT | |
630952c2 | 181 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
0af3fe1e PM |
182 | preempt_schedule(); /* Allow test to be preempted. */ |
183 | #endif | |
184 | } | |
185 | ||
186 | static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock) | |
187 | { | |
188 | spin_unlock(&torture_spinlock); | |
189 | } | |
190 | ||
191 | static struct lock_torture_ops spin_lock_ops = { | |
192 | .writelock = torture_spin_lock_write_lock, | |
193 | .write_delay = torture_spin_lock_write_delay, | |
095777c4 | 194 | .task_boost = torture_boost_dummy, |
0af3fe1e | 195 | .writeunlock = torture_spin_lock_write_unlock, |
4f6332c1 DB |
196 | .readlock = NULL, |
197 | .read_delay = NULL, | |
198 | .readunlock = NULL, | |
0af3fe1e PM |
199 | .name = "spin_lock" |
200 | }; | |
201 | ||
202 | static int torture_spin_lock_write_lock_irq(void) | |
219f800f | 203 | __acquires(torture_spinlock) |
0af3fe1e PM |
204 | { |
205 | unsigned long flags; | |
206 | ||
207 | spin_lock_irqsave(&torture_spinlock, flags); | |
630952c2 | 208 | cxt.cur_ops->flags = flags; |
0af3fe1e PM |
209 | return 0; |
210 | } | |
211 | ||
212 | static void torture_lock_spin_write_unlock_irq(void) | |
213 | __releases(torture_spinlock) | |
214 | { | |
630952c2 | 215 | spin_unlock_irqrestore(&torture_spinlock, cxt.cur_ops->flags); |
0af3fe1e PM |
216 | } |
217 | ||
218 | static struct lock_torture_ops spin_lock_irq_ops = { | |
219 | .writelock = torture_spin_lock_write_lock_irq, | |
220 | .write_delay = torture_spin_lock_write_delay, | |
095777c4 | 221 | .task_boost = torture_boost_dummy, |
0af3fe1e | 222 | .writeunlock = torture_lock_spin_write_unlock_irq, |
4f6332c1 DB |
223 | .readlock = NULL, |
224 | .read_delay = NULL, | |
225 | .readunlock = NULL, | |
0af3fe1e PM |
226 | .name = "spin_lock_irq" |
227 | }; | |
228 | ||
e34191fa DB |
229 | static DEFINE_RWLOCK(torture_rwlock); |
230 | ||
231 | static int torture_rwlock_write_lock(void) __acquires(torture_rwlock) | |
232 | { | |
233 | write_lock(&torture_rwlock); | |
234 | return 0; | |
235 | } | |
236 | ||
237 | static void torture_rwlock_write_delay(struct torture_random_state *trsp) | |
238 | { | |
239 | const unsigned long shortdelay_us = 2; | |
240 | const unsigned long longdelay_ms = 100; | |
241 | ||
242 | /* We want a short delay mostly to emulate likely code, and | |
243 | * we want a long delay occasionally to force massive contention. | |
244 | */ | |
245 | if (!(torture_random(trsp) % | |
246 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) | |
247 | mdelay(longdelay_ms); | |
248 | else | |
249 | udelay(shortdelay_us); | |
250 | } | |
251 | ||
252 | static void torture_rwlock_write_unlock(void) __releases(torture_rwlock) | |
253 | { | |
254 | write_unlock(&torture_rwlock); | |
255 | } | |
256 | ||
257 | static int torture_rwlock_read_lock(void) __acquires(torture_rwlock) | |
258 | { | |
259 | read_lock(&torture_rwlock); | |
260 | return 0; | |
261 | } | |
262 | ||
263 | static void torture_rwlock_read_delay(struct torture_random_state *trsp) | |
264 | { | |
265 | const unsigned long shortdelay_us = 10; | |
266 | const unsigned long longdelay_ms = 100; | |
267 | ||
268 | /* We want a short delay mostly to emulate likely code, and | |
269 | * we want a long delay occasionally to force massive contention. | |
270 | */ | |
271 | if (!(torture_random(trsp) % | |
272 | (cxt.nrealreaders_stress * 2000 * longdelay_ms))) | |
273 | mdelay(longdelay_ms); | |
274 | else | |
275 | udelay(shortdelay_us); | |
276 | } | |
277 | ||
278 | static void torture_rwlock_read_unlock(void) __releases(torture_rwlock) | |
279 | { | |
280 | read_unlock(&torture_rwlock); | |
281 | } | |
282 | ||
283 | static struct lock_torture_ops rw_lock_ops = { | |
284 | .writelock = torture_rwlock_write_lock, | |
285 | .write_delay = torture_rwlock_write_delay, | |
095777c4 | 286 | .task_boost = torture_boost_dummy, |
e34191fa DB |
287 | .writeunlock = torture_rwlock_write_unlock, |
288 | .readlock = torture_rwlock_read_lock, | |
289 | .read_delay = torture_rwlock_read_delay, | |
290 | .readunlock = torture_rwlock_read_unlock, | |
291 | .name = "rw_lock" | |
292 | }; | |
293 | ||
294 | static int torture_rwlock_write_lock_irq(void) __acquires(torture_rwlock) | |
295 | { | |
296 | unsigned long flags; | |
297 | ||
298 | write_lock_irqsave(&torture_rwlock, flags); | |
299 | cxt.cur_ops->flags = flags; | |
300 | return 0; | |
301 | } | |
302 | ||
303 | static void torture_rwlock_write_unlock_irq(void) | |
304 | __releases(torture_rwlock) | |
305 | { | |
306 | write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags); | |
307 | } | |
308 | ||
309 | static int torture_rwlock_read_lock_irq(void) __acquires(torture_rwlock) | |
310 | { | |
311 | unsigned long flags; | |
312 | ||
313 | read_lock_irqsave(&torture_rwlock, flags); | |
314 | cxt.cur_ops->flags = flags; | |
315 | return 0; | |
316 | } | |
317 | ||
318 | static void torture_rwlock_read_unlock_irq(void) | |
319 | __releases(torture_rwlock) | |
320 | { | |
f548d99e | 321 | read_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags); |
e34191fa DB |
322 | } |
323 | ||
324 | static struct lock_torture_ops rw_lock_irq_ops = { | |
325 | .writelock = torture_rwlock_write_lock_irq, | |
326 | .write_delay = torture_rwlock_write_delay, | |
095777c4 | 327 | .task_boost = torture_boost_dummy, |
e34191fa DB |
328 | .writeunlock = torture_rwlock_write_unlock_irq, |
329 | .readlock = torture_rwlock_read_lock_irq, | |
330 | .read_delay = torture_rwlock_read_delay, | |
331 | .readunlock = torture_rwlock_read_unlock_irq, | |
332 | .name = "rw_lock_irq" | |
333 | }; | |
334 | ||
42ddc75d DB |
335 | static DEFINE_MUTEX(torture_mutex); |
336 | ||
337 | static int torture_mutex_lock(void) __acquires(torture_mutex) | |
338 | { | |
339 | mutex_lock(&torture_mutex); | |
340 | return 0; | |
341 | } | |
342 | ||
343 | static void torture_mutex_delay(struct torture_random_state *trsp) | |
344 | { | |
345 | const unsigned long longdelay_ms = 100; | |
346 | ||
347 | /* We want a long delay occasionally to force massive contention. */ | |
348 | if (!(torture_random(trsp) % | |
630952c2 | 349 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
42ddc75d DB |
350 | mdelay(longdelay_ms * 5); |
351 | else | |
352 | mdelay(longdelay_ms / 5); | |
353 | #ifdef CONFIG_PREEMPT | |
630952c2 | 354 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
42ddc75d DB |
355 | preempt_schedule(); /* Allow test to be preempted. */ |
356 | #endif | |
357 | } | |
358 | ||
359 | static void torture_mutex_unlock(void) __releases(torture_mutex) | |
360 | { | |
361 | mutex_unlock(&torture_mutex); | |
362 | } | |
363 | ||
364 | static struct lock_torture_ops mutex_lock_ops = { | |
365 | .writelock = torture_mutex_lock, | |
366 | .write_delay = torture_mutex_delay, | |
095777c4 | 367 | .task_boost = torture_boost_dummy, |
42ddc75d | 368 | .writeunlock = torture_mutex_unlock, |
4f6332c1 DB |
369 | .readlock = NULL, |
370 | .read_delay = NULL, | |
371 | .readunlock = NULL, | |
42ddc75d DB |
372 | .name = "mutex_lock" |
373 | }; | |
374 | ||
095777c4 DB |
375 | #ifdef CONFIG_RT_MUTEXES |
376 | static DEFINE_RT_MUTEX(torture_rtmutex); | |
377 | ||
378 | static int torture_rtmutex_lock(void) __acquires(torture_rtmutex) | |
379 | { | |
380 | rt_mutex_lock(&torture_rtmutex); | |
381 | return 0; | |
382 | } | |
383 | ||
384 | static void torture_rtmutex_boost(struct torture_random_state *trsp) | |
385 | { | |
386 | int policy; | |
387 | struct sched_param param; | |
388 | const unsigned int factor = 50000; /* yes, quite arbitrary */ | |
389 | ||
390 | if (!rt_task(current)) { | |
391 | /* | |
1f190931 | 392 | * Boost priority once every ~50k operations. When the |
095777c4 DB |
393 | * task tries to take the lock, the rtmutex it will account |
394 | * for the new priority, and do any corresponding pi-dance. | |
395 | */ | |
1f190931 DB |
396 | if (trsp && !(torture_random(trsp) % |
397 | (cxt.nrealwriters_stress * factor))) { | |
095777c4 DB |
398 | policy = SCHED_FIFO; |
399 | param.sched_priority = MAX_RT_PRIO - 1; | |
400 | } else /* common case, do nothing */ | |
401 | return; | |
402 | } else { | |
403 | /* | |
404 | * The task will remain boosted for another ~500k operations, | |
405 | * then restored back to its original prio, and so forth. | |
406 | * | |
407 | * When @trsp is nil, we want to force-reset the task for | |
408 | * stopping the kthread. | |
409 | */ | |
410 | if (!trsp || !(torture_random(trsp) % | |
411 | (cxt.nrealwriters_stress * factor * 2))) { | |
412 | policy = SCHED_NORMAL; | |
413 | param.sched_priority = 0; | |
414 | } else /* common case, do nothing */ | |
415 | return; | |
416 | } | |
417 | ||
418 | sched_setscheduler_nocheck(current, policy, ¶m); | |
419 | } | |
420 | ||
421 | static void torture_rtmutex_delay(struct torture_random_state *trsp) | |
422 | { | |
423 | const unsigned long shortdelay_us = 2; | |
424 | const unsigned long longdelay_ms = 100; | |
425 | ||
426 | /* | |
427 | * We want a short delay mostly to emulate likely code, and | |
428 | * we want a long delay occasionally to force massive contention. | |
429 | */ | |
430 | if (!(torture_random(trsp) % | |
431 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) | |
432 | mdelay(longdelay_ms); | |
433 | if (!(torture_random(trsp) % | |
434 | (cxt.nrealwriters_stress * 2 * shortdelay_us))) | |
435 | udelay(shortdelay_us); | |
436 | #ifdef CONFIG_PREEMPT | |
437 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) | |
438 | preempt_schedule(); /* Allow test to be preempted. */ | |
439 | #endif | |
440 | } | |
441 | ||
442 | static void torture_rtmutex_unlock(void) __releases(torture_rtmutex) | |
443 | { | |
444 | rt_mutex_unlock(&torture_rtmutex); | |
445 | } | |
446 | ||
447 | static struct lock_torture_ops rtmutex_lock_ops = { | |
448 | .writelock = torture_rtmutex_lock, | |
449 | .write_delay = torture_rtmutex_delay, | |
450 | .task_boost = torture_rtmutex_boost, | |
451 | .writeunlock = torture_rtmutex_unlock, | |
452 | .readlock = NULL, | |
453 | .read_delay = NULL, | |
454 | .readunlock = NULL, | |
455 | .name = "rtmutex_lock" | |
456 | }; | |
457 | #endif | |
458 | ||
4a3b427f DB |
459 | static DECLARE_RWSEM(torture_rwsem); |
460 | static int torture_rwsem_down_write(void) __acquires(torture_rwsem) | |
461 | { | |
462 | down_write(&torture_rwsem); | |
463 | return 0; | |
464 | } | |
465 | ||
466 | static void torture_rwsem_write_delay(struct torture_random_state *trsp) | |
467 | { | |
468 | const unsigned long longdelay_ms = 100; | |
469 | ||
470 | /* We want a long delay occasionally to force massive contention. */ | |
471 | if (!(torture_random(trsp) % | |
630952c2 | 472 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
4a3b427f DB |
473 | mdelay(longdelay_ms * 10); |
474 | else | |
475 | mdelay(longdelay_ms / 10); | |
476 | #ifdef CONFIG_PREEMPT | |
630952c2 | 477 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
4a3b427f DB |
478 | preempt_schedule(); /* Allow test to be preempted. */ |
479 | #endif | |
480 | } | |
481 | ||
482 | static void torture_rwsem_up_write(void) __releases(torture_rwsem) | |
483 | { | |
484 | up_write(&torture_rwsem); | |
485 | } | |
486 | ||
487 | static int torture_rwsem_down_read(void) __acquires(torture_rwsem) | |
488 | { | |
489 | down_read(&torture_rwsem); | |
490 | return 0; | |
491 | } | |
492 | ||
493 | static void torture_rwsem_read_delay(struct torture_random_state *trsp) | |
494 | { | |
495 | const unsigned long longdelay_ms = 100; | |
496 | ||
497 | /* We want a long delay occasionally to force massive contention. */ | |
498 | if (!(torture_random(trsp) % | |
630952c2 | 499 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
4a3b427f DB |
500 | mdelay(longdelay_ms * 2); |
501 | else | |
502 | mdelay(longdelay_ms / 2); | |
503 | #ifdef CONFIG_PREEMPT | |
630952c2 | 504 | if (!(torture_random(trsp) % (cxt.nrealreaders_stress * 20000))) |
4a3b427f DB |
505 | preempt_schedule(); /* Allow test to be preempted. */ |
506 | #endif | |
507 | } | |
508 | ||
509 | static void torture_rwsem_up_read(void) __releases(torture_rwsem) | |
510 | { | |
511 | up_read(&torture_rwsem); | |
512 | } | |
513 | ||
514 | static struct lock_torture_ops rwsem_lock_ops = { | |
515 | .writelock = torture_rwsem_down_write, | |
516 | .write_delay = torture_rwsem_write_delay, | |
095777c4 | 517 | .task_boost = torture_boost_dummy, |
4a3b427f DB |
518 | .writeunlock = torture_rwsem_up_write, |
519 | .readlock = torture_rwsem_down_read, | |
520 | .read_delay = torture_rwsem_read_delay, | |
521 | .readunlock = torture_rwsem_up_read, | |
522 | .name = "rwsem_lock" | |
523 | }; | |
524 | ||
617783dd PM |
525 | #include <linux/percpu-rwsem.h> |
526 | static struct percpu_rw_semaphore pcpu_rwsem; | |
527 | ||
528 | void torture_percpu_rwsem_init(void) | |
529 | { | |
530 | BUG_ON(percpu_init_rwsem(&pcpu_rwsem)); | |
531 | } | |
532 | ||
533 | static int torture_percpu_rwsem_down_write(void) __acquires(pcpu_rwsem) | |
534 | { | |
535 | percpu_down_write(&pcpu_rwsem); | |
536 | return 0; | |
537 | } | |
538 | ||
539 | static void torture_percpu_rwsem_up_write(void) __releases(pcpu_rwsem) | |
540 | { | |
541 | percpu_up_write(&pcpu_rwsem); | |
542 | } | |
543 | ||
544 | static int torture_percpu_rwsem_down_read(void) __acquires(pcpu_rwsem) | |
545 | { | |
546 | percpu_down_read(&pcpu_rwsem); | |
547 | return 0; | |
548 | } | |
549 | ||
550 | static void torture_percpu_rwsem_up_read(void) __releases(pcpu_rwsem) | |
551 | { | |
552 | percpu_up_read(&pcpu_rwsem); | |
553 | } | |
554 | ||
555 | static struct lock_torture_ops percpu_rwsem_lock_ops = { | |
556 | .init = torture_percpu_rwsem_init, | |
557 | .writelock = torture_percpu_rwsem_down_write, | |
558 | .write_delay = torture_rwsem_write_delay, | |
559 | .task_boost = torture_boost_dummy, | |
560 | .writeunlock = torture_percpu_rwsem_up_write, | |
561 | .readlock = torture_percpu_rwsem_down_read, | |
562 | .read_delay = torture_rwsem_read_delay, | |
563 | .readunlock = torture_percpu_rwsem_up_read, | |
564 | .name = "percpu_rwsem_lock" | |
565 | }; | |
566 | ||
0af3fe1e PM |
567 | /* |
568 | * Lock torture writer kthread. Repeatedly acquires and releases | |
569 | * the lock, checking for duplicate acquisitions. | |
570 | */ | |
571 | static int lock_torture_writer(void *arg) | |
572 | { | |
1e6757a9 | 573 | struct lock_stress_stats *lwsp = arg; |
0af3fe1e PM |
574 | static DEFINE_TORTURE_RANDOM(rand); |
575 | ||
576 | VERBOSE_TOROUT_STRING("lock_torture_writer task started"); | |
8698a745 | 577 | set_user_nice(current, MAX_NICE); |
0af3fe1e PM |
578 | |
579 | do { | |
da601c63 PM |
580 | if ((torture_random(&rand) & 0xfffff) == 0) |
581 | schedule_timeout_uninterruptible(1); | |
a1229491 | 582 | |
095777c4 | 583 | cxt.cur_ops->task_boost(&rand); |
630952c2 | 584 | cxt.cur_ops->writelock(); |
0af3fe1e | 585 | if (WARN_ON_ONCE(lock_is_write_held)) |
1e6757a9 | 586 | lwsp->n_lock_fail++; |
0af3fe1e | 587 | lock_is_write_held = 1; |
a1229491 DB |
588 | if (WARN_ON_ONCE(lock_is_read_held)) |
589 | lwsp->n_lock_fail++; /* rare, but... */ | |
590 | ||
1e6757a9 | 591 | lwsp->n_lock_acquired++; |
630952c2 | 592 | cxt.cur_ops->write_delay(&rand); |
0af3fe1e | 593 | lock_is_write_held = 0; |
630952c2 | 594 | cxt.cur_ops->writeunlock(); |
a1229491 | 595 | |
0af3fe1e PM |
596 | stutter_wait("lock_torture_writer"); |
597 | } while (!torture_must_stop()); | |
095777c4 DB |
598 | |
599 | cxt.cur_ops->task_boost(NULL); /* reset prio */ | |
0af3fe1e PM |
600 | torture_kthread_stopping("lock_torture_writer"); |
601 | return 0; | |
602 | } | |
603 | ||
4f6332c1 DB |
604 | /* |
605 | * Lock torture reader kthread. Repeatedly acquires and releases | |
606 | * the reader lock. | |
607 | */ | |
608 | static int lock_torture_reader(void *arg) | |
609 | { | |
610 | struct lock_stress_stats *lrsp = arg; | |
611 | static DEFINE_TORTURE_RANDOM(rand); | |
612 | ||
613 | VERBOSE_TOROUT_STRING("lock_torture_reader task started"); | |
614 | set_user_nice(current, MAX_NICE); | |
615 | ||
616 | do { | |
617 | if ((torture_random(&rand) & 0xfffff) == 0) | |
618 | schedule_timeout_uninterruptible(1); | |
a1229491 | 619 | |
630952c2 | 620 | cxt.cur_ops->readlock(); |
4f6332c1 | 621 | lock_is_read_held = 1; |
a1229491 DB |
622 | if (WARN_ON_ONCE(lock_is_write_held)) |
623 | lrsp->n_lock_fail++; /* rare, but... */ | |
624 | ||
4f6332c1 | 625 | lrsp->n_lock_acquired++; |
630952c2 | 626 | cxt.cur_ops->read_delay(&rand); |
4f6332c1 | 627 | lock_is_read_held = 0; |
630952c2 | 628 | cxt.cur_ops->readunlock(); |
a1229491 | 629 | |
4f6332c1 DB |
630 | stutter_wait("lock_torture_reader"); |
631 | } while (!torture_must_stop()); | |
632 | torture_kthread_stopping("lock_torture_reader"); | |
633 | return 0; | |
634 | } | |
635 | ||
0af3fe1e PM |
636 | /* |
637 | * Create an lock-torture-statistics message in the specified buffer. | |
638 | */ | |
4f6332c1 DB |
639 | static void __torture_print_stats(char *page, |
640 | struct lock_stress_stats *statp, bool write) | |
0af3fe1e PM |
641 | { |
642 | bool fail = 0; | |
4f6332c1 | 643 | int i, n_stress; |
0af3fe1e | 644 | long max = 0; |
4f6332c1 | 645 | long min = statp[0].n_lock_acquired; |
0af3fe1e PM |
646 | long long sum = 0; |
647 | ||
630952c2 | 648 | n_stress = write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress; |
4f6332c1 DB |
649 | for (i = 0; i < n_stress; i++) { |
650 | if (statp[i].n_lock_fail) | |
0af3fe1e | 651 | fail = true; |
4f6332c1 DB |
652 | sum += statp[i].n_lock_acquired; |
653 | if (max < statp[i].n_lock_fail) | |
654 | max = statp[i].n_lock_fail; | |
655 | if (min > statp[i].n_lock_fail) | |
656 | min = statp[i].n_lock_fail; | |
0af3fe1e | 657 | } |
0af3fe1e | 658 | page += sprintf(page, |
4f6332c1 DB |
659 | "%s: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n", |
660 | write ? "Writes" : "Reads ", | |
0af3fe1e PM |
661 | sum, max, min, max / 2 > min ? "???" : "", |
662 | fail, fail ? "!!!" : ""); | |
663 | if (fail) | |
630952c2 | 664 | atomic_inc(&cxt.n_lock_torture_errors); |
0af3fe1e PM |
665 | } |
666 | ||
667 | /* | |
668 | * Print torture statistics. Caller must ensure that there is only one | |
669 | * call to this function at a given time!!! This is normally accomplished | |
670 | * by relying on the module system to only have one copy of the module | |
671 | * loaded, and then by giving the lock_torture_stats kthread full control | |
672 | * (or the init/cleanup functions when lock_torture_stats thread is not | |
673 | * running). | |
674 | */ | |
675 | static void lock_torture_stats_print(void) | |
676 | { | |
630952c2 | 677 | int size = cxt.nrealwriters_stress * 200 + 8192; |
0af3fe1e PM |
678 | char *buf; |
679 | ||
630952c2 DB |
680 | if (cxt.cur_ops->readlock) |
681 | size += cxt.nrealreaders_stress * 200 + 8192; | |
4f6332c1 | 682 | |
0af3fe1e PM |
683 | buf = kmalloc(size, GFP_KERNEL); |
684 | if (!buf) { | |
685 | pr_err("lock_torture_stats_print: Out of memory, need: %d", | |
686 | size); | |
687 | return; | |
688 | } | |
4f6332c1 | 689 | |
630952c2 | 690 | __torture_print_stats(buf, cxt.lwsa, true); |
0af3fe1e PM |
691 | pr_alert("%s", buf); |
692 | kfree(buf); | |
4f6332c1 | 693 | |
630952c2 | 694 | if (cxt.cur_ops->readlock) { |
4f6332c1 DB |
695 | buf = kmalloc(size, GFP_KERNEL); |
696 | if (!buf) { | |
697 | pr_err("lock_torture_stats_print: Out of memory, need: %d", | |
698 | size); | |
699 | return; | |
700 | } | |
701 | ||
630952c2 | 702 | __torture_print_stats(buf, cxt.lrsa, false); |
4f6332c1 DB |
703 | pr_alert("%s", buf); |
704 | kfree(buf); | |
705 | } | |
0af3fe1e PM |
706 | } |
707 | ||
708 | /* | |
709 | * Periodically prints torture statistics, if periodic statistics printing | |
710 | * was specified via the stat_interval module parameter. | |
711 | * | |
712 | * No need to worry about fullstop here, since this one doesn't reference | |
713 | * volatile state or register callbacks. | |
714 | */ | |
715 | static int lock_torture_stats(void *arg) | |
716 | { | |
717 | VERBOSE_TOROUT_STRING("lock_torture_stats task started"); | |
718 | do { | |
719 | schedule_timeout_interruptible(stat_interval * HZ); | |
720 | lock_torture_stats_print(); | |
721 | torture_shutdown_absorb("lock_torture_stats"); | |
722 | } while (!torture_must_stop()); | |
723 | torture_kthread_stopping("lock_torture_stats"); | |
724 | return 0; | |
725 | } | |
726 | ||
727 | static inline void | |
728 | lock_torture_print_module_parms(struct lock_torture_ops *cur_ops, | |
729 | const char *tag) | |
730 | { | |
731 | pr_alert("%s" TORTURE_FLAG | |
4f6332c1 | 732 | "--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n", |
630952c2 DB |
733 | torture_type, tag, cxt.debug_lock ? " [debug]": "", |
734 | cxt.nrealwriters_stress, cxt.nrealreaders_stress, stat_interval, | |
4f6332c1 | 735 | verbose, shuffle_interval, stutter, shutdown_secs, |
0af3fe1e PM |
736 | onoff_interval, onoff_holdoff); |
737 | } | |
738 | ||
739 | static void lock_torture_cleanup(void) | |
740 | { | |
741 | int i; | |
742 | ||
d36a7a0d | 743 | if (torture_cleanup_begin()) |
0af3fe1e PM |
744 | return; |
745 | ||
c1c33b92 DB |
746 | /* |
747 | * Indicates early cleanup, meaning that the test has not run, | |
748 | * such as when passing bogus args when loading the module. As | |
749 | * such, only perform the underlying torture-specific cleanups, | |
750 | * and avoid anything related to locktorture. | |
751 | */ | |
752 | if (!cxt.lwsa) | |
753 | goto end; | |
754 | ||
0af3fe1e | 755 | if (writer_tasks) { |
630952c2 | 756 | for (i = 0; i < cxt.nrealwriters_stress; i++) |
0af3fe1e PM |
757 | torture_stop_kthread(lock_torture_writer, |
758 | writer_tasks[i]); | |
759 | kfree(writer_tasks); | |
760 | writer_tasks = NULL; | |
761 | } | |
762 | ||
4f6332c1 | 763 | if (reader_tasks) { |
630952c2 | 764 | for (i = 0; i < cxt.nrealreaders_stress; i++) |
4f6332c1 DB |
765 | torture_stop_kthread(lock_torture_reader, |
766 | reader_tasks[i]); | |
767 | kfree(reader_tasks); | |
768 | reader_tasks = NULL; | |
769 | } | |
770 | ||
0af3fe1e PM |
771 | torture_stop_kthread(lock_torture_stats, stats_task); |
772 | lock_torture_stats_print(); /* -After- the stats thread is stopped! */ | |
773 | ||
630952c2 DB |
774 | if (atomic_read(&cxt.n_lock_torture_errors)) |
775 | lock_torture_print_module_parms(cxt.cur_ops, | |
0af3fe1e PM |
776 | "End of test: FAILURE"); |
777 | else if (torture_onoff_failures()) | |
630952c2 | 778 | lock_torture_print_module_parms(cxt.cur_ops, |
0af3fe1e PM |
779 | "End of test: LOCK_HOTPLUG"); |
780 | else | |
630952c2 | 781 | lock_torture_print_module_parms(cxt.cur_ops, |
0af3fe1e | 782 | "End of test: SUCCESS"); |
c1c33b92 | 783 | end: |
d36a7a0d | 784 | torture_cleanup_end(); |
0af3fe1e PM |
785 | } |
786 | ||
787 | static int __init lock_torture_init(void) | |
788 | { | |
4f6332c1 | 789 | int i, j; |
0af3fe1e PM |
790 | int firsterr = 0; |
791 | static struct lock_torture_ops *torture_ops[] = { | |
e34191fa DB |
792 | &lock_busted_ops, |
793 | &spin_lock_ops, &spin_lock_irq_ops, | |
794 | &rw_lock_ops, &rw_lock_irq_ops, | |
795 | &mutex_lock_ops, | |
095777c4 DB |
796 | #ifdef CONFIG_RT_MUTEXES |
797 | &rtmutex_lock_ops, | |
798 | #endif | |
e34191fa | 799 | &rwsem_lock_ops, |
617783dd | 800 | &percpu_rwsem_lock_ops, |
0af3fe1e PM |
801 | }; |
802 | ||
23a8e5c2 | 803 | if (!torture_init_begin(torture_type, verbose, &torture_runnable)) |
5228084e | 804 | return -EBUSY; |
0af3fe1e PM |
805 | |
806 | /* Process args and tell the world that the torturer is on the job. */ | |
807 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { | |
630952c2 DB |
808 | cxt.cur_ops = torture_ops[i]; |
809 | if (strcmp(torture_type, cxt.cur_ops->name) == 0) | |
0af3fe1e PM |
810 | break; |
811 | } | |
812 | if (i == ARRAY_SIZE(torture_ops)) { | |
813 | pr_alert("lock-torture: invalid torture type: \"%s\"\n", | |
814 | torture_type); | |
815 | pr_alert("lock-torture types:"); | |
816 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
817 | pr_alert(" %s", torture_ops[i]->name); | |
818 | pr_alert("\n"); | |
a36a9961 PM |
819 | firsterr = -EINVAL; |
820 | goto unwind; | |
0af3fe1e | 821 | } |
630952c2 | 822 | if (cxt.cur_ops->init) |
a36a9961 | 823 | cxt.cur_ops->init(); |
0af3fe1e PM |
824 | |
825 | if (nwriters_stress >= 0) | |
630952c2 | 826 | cxt.nrealwriters_stress = nwriters_stress; |
0af3fe1e | 827 | else |
630952c2 | 828 | cxt.nrealwriters_stress = 2 * num_online_cpus(); |
f095bfc0 DB |
829 | |
830 | #ifdef CONFIG_DEBUG_MUTEXES | |
831 | if (strncmp(torture_type, "mutex", 5) == 0) | |
630952c2 | 832 | cxt.debug_lock = true; |
f095bfc0 | 833 | #endif |
095777c4 DB |
834 | #ifdef CONFIG_DEBUG_RT_MUTEXES |
835 | if (strncmp(torture_type, "rtmutex", 7) == 0) | |
836 | cxt.debug_lock = true; | |
837 | #endif | |
f095bfc0 | 838 | #ifdef CONFIG_DEBUG_SPINLOCK |
e34191fa DB |
839 | if ((strncmp(torture_type, "spin", 4) == 0) || |
840 | (strncmp(torture_type, "rw_lock", 7) == 0)) | |
630952c2 | 841 | cxt.debug_lock = true; |
f095bfc0 | 842 | #endif |
0af3fe1e PM |
843 | |
844 | /* Initialize the statistics so that each run gets its own numbers. */ | |
845 | ||
846 | lock_is_write_held = 0; | |
630952c2 DB |
847 | cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL); |
848 | if (cxt.lwsa == NULL) { | |
849 | VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory"); | |
0af3fe1e PM |
850 | firsterr = -ENOMEM; |
851 | goto unwind; | |
852 | } | |
630952c2 DB |
853 | for (i = 0; i < cxt.nrealwriters_stress; i++) { |
854 | cxt.lwsa[i].n_lock_fail = 0; | |
855 | cxt.lwsa[i].n_lock_acquired = 0; | |
0af3fe1e PM |
856 | } |
857 | ||
630952c2 | 858 | if (cxt.cur_ops->readlock) { |
4f6332c1 | 859 | if (nreaders_stress >= 0) |
630952c2 | 860 | cxt.nrealreaders_stress = nreaders_stress; |
4f6332c1 DB |
861 | else { |
862 | /* | |
863 | * By default distribute evenly the number of | |
864 | * readers and writers. We still run the same number | |
865 | * of threads as the writer-only locks default. | |
866 | */ | |
867 | if (nwriters_stress < 0) /* user doesn't care */ | |
630952c2 DB |
868 | cxt.nrealwriters_stress = num_online_cpus(); |
869 | cxt.nrealreaders_stress = cxt.nrealwriters_stress; | |
4f6332c1 DB |
870 | } |
871 | ||
872 | lock_is_read_held = 0; | |
630952c2 DB |
873 | cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL); |
874 | if (cxt.lrsa == NULL) { | |
875 | VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); | |
4f6332c1 | 876 | firsterr = -ENOMEM; |
630952c2 | 877 | kfree(cxt.lwsa); |
c1c33b92 | 878 | cxt.lwsa = NULL; |
4f6332c1 DB |
879 | goto unwind; |
880 | } | |
0af3fe1e | 881 | |
630952c2 DB |
882 | for (i = 0; i < cxt.nrealreaders_stress; i++) { |
883 | cxt.lrsa[i].n_lock_fail = 0; | |
884 | cxt.lrsa[i].n_lock_acquired = 0; | |
4f6332c1 DB |
885 | } |
886 | } | |
c1c33b92 | 887 | |
630952c2 | 888 | lock_torture_print_module_parms(cxt.cur_ops, "Start of test"); |
4f6332c1 DB |
889 | |
890 | /* Prepare torture context. */ | |
0af3fe1e PM |
891 | if (onoff_interval > 0) { |
892 | firsterr = torture_onoff_init(onoff_holdoff * HZ, | |
893 | onoff_interval * HZ); | |
894 | if (firsterr) | |
895 | goto unwind; | |
896 | } | |
897 | if (shuffle_interval > 0) { | |
898 | firsterr = torture_shuffle_init(shuffle_interval); | |
899 | if (firsterr) | |
900 | goto unwind; | |
901 | } | |
902 | if (shutdown_secs > 0) { | |
903 | firsterr = torture_shutdown_init(shutdown_secs, | |
904 | lock_torture_cleanup); | |
905 | if (firsterr) | |
906 | goto unwind; | |
907 | } | |
908 | if (stutter > 0) { | |
909 | firsterr = torture_stutter_init(stutter); | |
910 | if (firsterr) | |
911 | goto unwind; | |
912 | } | |
913 | ||
630952c2 | 914 | writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]), |
0af3fe1e PM |
915 | GFP_KERNEL); |
916 | if (writer_tasks == NULL) { | |
917 | VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); | |
918 | firsterr = -ENOMEM; | |
919 | goto unwind; | |
920 | } | |
4f6332c1 | 921 | |
630952c2 DB |
922 | if (cxt.cur_ops->readlock) { |
923 | reader_tasks = kzalloc(cxt.nrealreaders_stress * sizeof(reader_tasks[0]), | |
4f6332c1 DB |
924 | GFP_KERNEL); |
925 | if (reader_tasks == NULL) { | |
926 | VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory"); | |
927 | firsterr = -ENOMEM; | |
928 | goto unwind; | |
929 | } | |
930 | } | |
931 | ||
932 | /* | |
933 | * Create the kthreads and start torturing (oh, those poor little locks). | |
934 | * | |
935 | * TODO: Note that we interleave writers with readers, giving writers a | |
936 | * slight advantage, by creating its kthread first. This can be modified | |
937 | * for very specific needs, or even let the user choose the policy, if | |
938 | * ever wanted. | |
939 | */ | |
630952c2 DB |
940 | for (i = 0, j = 0; i < cxt.nrealwriters_stress || |
941 | j < cxt.nrealreaders_stress; i++, j++) { | |
942 | if (i >= cxt.nrealwriters_stress) | |
4f6332c1 DB |
943 | goto create_reader; |
944 | ||
945 | /* Create writer. */ | |
630952c2 | 946 | firsterr = torture_create_kthread(lock_torture_writer, &cxt.lwsa[i], |
0af3fe1e PM |
947 | writer_tasks[i]); |
948 | if (firsterr) | |
949 | goto unwind; | |
4f6332c1 DB |
950 | |
951 | create_reader: | |
630952c2 | 952 | if (cxt.cur_ops->readlock == NULL || (j >= cxt.nrealreaders_stress)) |
4f6332c1 DB |
953 | continue; |
954 | /* Create reader. */ | |
630952c2 | 955 | firsterr = torture_create_kthread(lock_torture_reader, &cxt.lrsa[j], |
4f6332c1 DB |
956 | reader_tasks[j]); |
957 | if (firsterr) | |
958 | goto unwind; | |
0af3fe1e PM |
959 | } |
960 | if (stat_interval > 0) { | |
961 | firsterr = torture_create_kthread(lock_torture_stats, NULL, | |
962 | stats_task); | |
963 | if (firsterr) | |
964 | goto unwind; | |
965 | } | |
966 | torture_init_end(); | |
967 | return 0; | |
968 | ||
969 | unwind: | |
970 | torture_init_end(); | |
971 | lock_torture_cleanup(); | |
972 | return firsterr; | |
973 | } | |
974 | ||
975 | module_init(lock_torture_init); | |
976 | module_exit(lock_torture_cleanup); |