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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 | |
d065eacf | 78 | #if defined(MODULE) |
0af3fe1e PM |
79 | #define LOCKTORTURE_RUNNABLE_INIT 1 |
80 | #else | |
81 | #define LOCKTORTURE_RUNNABLE_INIT 0 | |
82 | #endif | |
23a8e5c2 DB |
83 | int torture_runnable = LOCKTORTURE_RUNNABLE_INIT; |
84 | module_param(torture_runnable, int, 0444); | |
85 | MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init"); | |
0af3fe1e PM |
86 | |
87 | /* Forward reference. */ | |
88 | static void lock_torture_cleanup(void); | |
89 | ||
90 | /* | |
91 | * Operations vector for selecting different types of tests. | |
92 | */ | |
93 | struct lock_torture_ops { | |
94 | void (*init)(void); | |
95 | int (*writelock)(void); | |
96 | void (*write_delay)(struct torture_random_state *trsp); | |
095777c4 | 97 | void (*task_boost)(struct torture_random_state *trsp); |
0af3fe1e | 98 | void (*writeunlock)(void); |
4f6332c1 DB |
99 | int (*readlock)(void); |
100 | void (*read_delay)(struct torture_random_state *trsp); | |
101 | void (*readunlock)(void); | |
095777c4 DB |
102 | |
103 | unsigned long flags; /* for irq spinlocks */ | |
0af3fe1e PM |
104 | const char *name; |
105 | }; | |
106 | ||
630952c2 DB |
107 | struct lock_torture_cxt { |
108 | int nrealwriters_stress; | |
109 | int nrealreaders_stress; | |
110 | bool debug_lock; | |
111 | atomic_t n_lock_torture_errors; | |
112 | struct lock_torture_ops *cur_ops; | |
113 | struct lock_stress_stats *lwsa; /* writer statistics */ | |
114 | struct lock_stress_stats *lrsa; /* reader statistics */ | |
115 | }; | |
116 | static struct lock_torture_cxt cxt = { 0, 0, false, | |
117 | ATOMIC_INIT(0), | |
118 | NULL, NULL}; | |
0af3fe1e PM |
119 | /* |
120 | * Definitions for lock torture testing. | |
121 | */ | |
122 | ||
e086481b PM |
123 | static int torture_lock_busted_write_lock(void) |
124 | { | |
125 | return 0; /* BUGGY, do not use in real life!!! */ | |
126 | } | |
127 | ||
128 | static void torture_lock_busted_write_delay(struct torture_random_state *trsp) | |
129 | { | |
61d49d2f | 130 | const unsigned long longdelay_ms = 100; |
e086481b PM |
131 | |
132 | /* We want a long delay occasionally to force massive contention. */ | |
133 | if (!(torture_random(trsp) % | |
61d49d2f PM |
134 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
135 | mdelay(longdelay_ms); | |
e086481b | 136 | #ifdef CONFIG_PREEMPT |
630952c2 | 137 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
e086481b PM |
138 | preempt_schedule(); /* Allow test to be preempted. */ |
139 | #endif | |
140 | } | |
141 | ||
142 | static void torture_lock_busted_write_unlock(void) | |
143 | { | |
144 | /* BUGGY, do not use in real life!!! */ | |
145 | } | |
146 | ||
095777c4 DB |
147 | static void torture_boost_dummy(struct torture_random_state *trsp) |
148 | { | |
149 | /* Only rtmutexes care about priority */ | |
150 | } | |
151 | ||
e086481b PM |
152 | static struct lock_torture_ops lock_busted_ops = { |
153 | .writelock = torture_lock_busted_write_lock, | |
154 | .write_delay = torture_lock_busted_write_delay, | |
095777c4 | 155 | .task_boost = torture_boost_dummy, |
e086481b | 156 | .writeunlock = torture_lock_busted_write_unlock, |
4f6332c1 DB |
157 | .readlock = NULL, |
158 | .read_delay = NULL, | |
159 | .readunlock = NULL, | |
e086481b PM |
160 | .name = "lock_busted" |
161 | }; | |
162 | ||
0af3fe1e PM |
163 | static DEFINE_SPINLOCK(torture_spinlock); |
164 | ||
165 | static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock) | |
166 | { | |
167 | spin_lock(&torture_spinlock); | |
168 | return 0; | |
169 | } | |
170 | ||
171 | static void torture_spin_lock_write_delay(struct torture_random_state *trsp) | |
172 | { | |
173 | const unsigned long shortdelay_us = 2; | |
61d49d2f | 174 | const unsigned long longdelay_ms = 100; |
0af3fe1e PM |
175 | |
176 | /* We want a short delay mostly to emulate likely code, and | |
177 | * we want a long delay occasionally to force massive contention. | |
178 | */ | |
179 | if (!(torture_random(trsp) % | |
61d49d2f PM |
180 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
181 | mdelay(longdelay_ms); | |
0af3fe1e | 182 | if (!(torture_random(trsp) % |
630952c2 | 183 | (cxt.nrealwriters_stress * 2 * shortdelay_us))) |
0af3fe1e PM |
184 | udelay(shortdelay_us); |
185 | #ifdef CONFIG_PREEMPT | |
630952c2 | 186 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
0af3fe1e PM |
187 | preempt_schedule(); /* Allow test to be preempted. */ |
188 | #endif | |
189 | } | |
190 | ||
191 | static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock) | |
192 | { | |
193 | spin_unlock(&torture_spinlock); | |
194 | } | |
195 | ||
196 | static struct lock_torture_ops spin_lock_ops = { | |
197 | .writelock = torture_spin_lock_write_lock, | |
198 | .write_delay = torture_spin_lock_write_delay, | |
095777c4 | 199 | .task_boost = torture_boost_dummy, |
0af3fe1e | 200 | .writeunlock = torture_spin_lock_write_unlock, |
4f6332c1 DB |
201 | .readlock = NULL, |
202 | .read_delay = NULL, | |
203 | .readunlock = NULL, | |
0af3fe1e PM |
204 | .name = "spin_lock" |
205 | }; | |
206 | ||
207 | static int torture_spin_lock_write_lock_irq(void) | |
219f800f | 208 | __acquires(torture_spinlock) |
0af3fe1e PM |
209 | { |
210 | unsigned long flags; | |
211 | ||
212 | spin_lock_irqsave(&torture_spinlock, flags); | |
630952c2 | 213 | cxt.cur_ops->flags = flags; |
0af3fe1e PM |
214 | return 0; |
215 | } | |
216 | ||
217 | static void torture_lock_spin_write_unlock_irq(void) | |
218 | __releases(torture_spinlock) | |
219 | { | |
630952c2 | 220 | spin_unlock_irqrestore(&torture_spinlock, cxt.cur_ops->flags); |
0af3fe1e PM |
221 | } |
222 | ||
223 | static struct lock_torture_ops spin_lock_irq_ops = { | |
224 | .writelock = torture_spin_lock_write_lock_irq, | |
225 | .write_delay = torture_spin_lock_write_delay, | |
095777c4 | 226 | .task_boost = torture_boost_dummy, |
0af3fe1e | 227 | .writeunlock = torture_lock_spin_write_unlock_irq, |
4f6332c1 DB |
228 | .readlock = NULL, |
229 | .read_delay = NULL, | |
230 | .readunlock = NULL, | |
0af3fe1e PM |
231 | .name = "spin_lock_irq" |
232 | }; | |
233 | ||
e34191fa DB |
234 | static DEFINE_RWLOCK(torture_rwlock); |
235 | ||
236 | static int torture_rwlock_write_lock(void) __acquires(torture_rwlock) | |
237 | { | |
238 | write_lock(&torture_rwlock); | |
239 | return 0; | |
240 | } | |
241 | ||
242 | static void torture_rwlock_write_delay(struct torture_random_state *trsp) | |
243 | { | |
244 | const unsigned long shortdelay_us = 2; | |
245 | const unsigned long longdelay_ms = 100; | |
246 | ||
247 | /* We want a short delay mostly to emulate likely code, and | |
248 | * we want a long delay occasionally to force massive contention. | |
249 | */ | |
250 | if (!(torture_random(trsp) % | |
251 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) | |
252 | mdelay(longdelay_ms); | |
253 | else | |
254 | udelay(shortdelay_us); | |
255 | } | |
256 | ||
257 | static void torture_rwlock_write_unlock(void) __releases(torture_rwlock) | |
258 | { | |
259 | write_unlock(&torture_rwlock); | |
260 | } | |
261 | ||
262 | static int torture_rwlock_read_lock(void) __acquires(torture_rwlock) | |
263 | { | |
264 | read_lock(&torture_rwlock); | |
265 | return 0; | |
266 | } | |
267 | ||
268 | static void torture_rwlock_read_delay(struct torture_random_state *trsp) | |
269 | { | |
270 | const unsigned long shortdelay_us = 10; | |
271 | const unsigned long longdelay_ms = 100; | |
272 | ||
273 | /* We want a short delay mostly to emulate likely code, and | |
274 | * we want a long delay occasionally to force massive contention. | |
275 | */ | |
276 | if (!(torture_random(trsp) % | |
277 | (cxt.nrealreaders_stress * 2000 * longdelay_ms))) | |
278 | mdelay(longdelay_ms); | |
279 | else | |
280 | udelay(shortdelay_us); | |
281 | } | |
282 | ||
283 | static void torture_rwlock_read_unlock(void) __releases(torture_rwlock) | |
284 | { | |
285 | read_unlock(&torture_rwlock); | |
286 | } | |
287 | ||
288 | static struct lock_torture_ops rw_lock_ops = { | |
289 | .writelock = torture_rwlock_write_lock, | |
290 | .write_delay = torture_rwlock_write_delay, | |
095777c4 | 291 | .task_boost = torture_boost_dummy, |
e34191fa DB |
292 | .writeunlock = torture_rwlock_write_unlock, |
293 | .readlock = torture_rwlock_read_lock, | |
294 | .read_delay = torture_rwlock_read_delay, | |
295 | .readunlock = torture_rwlock_read_unlock, | |
296 | .name = "rw_lock" | |
297 | }; | |
298 | ||
299 | static int torture_rwlock_write_lock_irq(void) __acquires(torture_rwlock) | |
300 | { | |
301 | unsigned long flags; | |
302 | ||
303 | write_lock_irqsave(&torture_rwlock, flags); | |
304 | cxt.cur_ops->flags = flags; | |
305 | return 0; | |
306 | } | |
307 | ||
308 | static void torture_rwlock_write_unlock_irq(void) | |
309 | __releases(torture_rwlock) | |
310 | { | |
311 | write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags); | |
312 | } | |
313 | ||
314 | static int torture_rwlock_read_lock_irq(void) __acquires(torture_rwlock) | |
315 | { | |
316 | unsigned long flags; | |
317 | ||
318 | read_lock_irqsave(&torture_rwlock, flags); | |
319 | cxt.cur_ops->flags = flags; | |
320 | return 0; | |
321 | } | |
322 | ||
323 | static void torture_rwlock_read_unlock_irq(void) | |
324 | __releases(torture_rwlock) | |
325 | { | |
f548d99e | 326 | read_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags); |
e34191fa DB |
327 | } |
328 | ||
329 | static struct lock_torture_ops rw_lock_irq_ops = { | |
330 | .writelock = torture_rwlock_write_lock_irq, | |
331 | .write_delay = torture_rwlock_write_delay, | |
095777c4 | 332 | .task_boost = torture_boost_dummy, |
e34191fa DB |
333 | .writeunlock = torture_rwlock_write_unlock_irq, |
334 | .readlock = torture_rwlock_read_lock_irq, | |
335 | .read_delay = torture_rwlock_read_delay, | |
336 | .readunlock = torture_rwlock_read_unlock_irq, | |
337 | .name = "rw_lock_irq" | |
338 | }; | |
339 | ||
42ddc75d DB |
340 | static DEFINE_MUTEX(torture_mutex); |
341 | ||
342 | static int torture_mutex_lock(void) __acquires(torture_mutex) | |
343 | { | |
344 | mutex_lock(&torture_mutex); | |
345 | return 0; | |
346 | } | |
347 | ||
348 | static void torture_mutex_delay(struct torture_random_state *trsp) | |
349 | { | |
350 | const unsigned long longdelay_ms = 100; | |
351 | ||
352 | /* We want a long delay occasionally to force massive contention. */ | |
353 | if (!(torture_random(trsp) % | |
630952c2 | 354 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
42ddc75d DB |
355 | mdelay(longdelay_ms * 5); |
356 | else | |
357 | mdelay(longdelay_ms / 5); | |
358 | #ifdef CONFIG_PREEMPT | |
630952c2 | 359 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
42ddc75d DB |
360 | preempt_schedule(); /* Allow test to be preempted. */ |
361 | #endif | |
362 | } | |
363 | ||
364 | static void torture_mutex_unlock(void) __releases(torture_mutex) | |
365 | { | |
366 | mutex_unlock(&torture_mutex); | |
367 | } | |
368 | ||
369 | static struct lock_torture_ops mutex_lock_ops = { | |
370 | .writelock = torture_mutex_lock, | |
371 | .write_delay = torture_mutex_delay, | |
095777c4 | 372 | .task_boost = torture_boost_dummy, |
42ddc75d | 373 | .writeunlock = torture_mutex_unlock, |
4f6332c1 DB |
374 | .readlock = NULL, |
375 | .read_delay = NULL, | |
376 | .readunlock = NULL, | |
42ddc75d DB |
377 | .name = "mutex_lock" |
378 | }; | |
379 | ||
095777c4 DB |
380 | #ifdef CONFIG_RT_MUTEXES |
381 | static DEFINE_RT_MUTEX(torture_rtmutex); | |
382 | ||
383 | static int torture_rtmutex_lock(void) __acquires(torture_rtmutex) | |
384 | { | |
385 | rt_mutex_lock(&torture_rtmutex); | |
386 | return 0; | |
387 | } | |
388 | ||
389 | static void torture_rtmutex_boost(struct torture_random_state *trsp) | |
390 | { | |
391 | int policy; | |
392 | struct sched_param param; | |
393 | const unsigned int factor = 50000; /* yes, quite arbitrary */ | |
394 | ||
395 | if (!rt_task(current)) { | |
396 | /* | |
397 | * (1) Boost priority once every ~50k operations. When the | |
398 | * task tries to take the lock, the rtmutex it will account | |
399 | * for the new priority, and do any corresponding pi-dance. | |
400 | */ | |
401 | if (!(torture_random(trsp) % | |
402 | (cxt.nrealwriters_stress * factor))) { | |
403 | policy = SCHED_FIFO; | |
404 | param.sched_priority = MAX_RT_PRIO - 1; | |
405 | } else /* common case, do nothing */ | |
406 | return; | |
407 | } else { | |
408 | /* | |
409 | * The task will remain boosted for another ~500k operations, | |
410 | * then restored back to its original prio, and so forth. | |
411 | * | |
412 | * When @trsp is nil, we want to force-reset the task for | |
413 | * stopping the kthread. | |
414 | */ | |
415 | if (!trsp || !(torture_random(trsp) % | |
416 | (cxt.nrealwriters_stress * factor * 2))) { | |
417 | policy = SCHED_NORMAL; | |
418 | param.sched_priority = 0; | |
419 | } else /* common case, do nothing */ | |
420 | return; | |
421 | } | |
422 | ||
423 | sched_setscheduler_nocheck(current, policy, ¶m); | |
424 | } | |
425 | ||
426 | static void torture_rtmutex_delay(struct torture_random_state *trsp) | |
427 | { | |
428 | const unsigned long shortdelay_us = 2; | |
429 | const unsigned long longdelay_ms = 100; | |
430 | ||
431 | /* | |
432 | * We want a short delay mostly to emulate likely code, and | |
433 | * we want a long delay occasionally to force massive contention. | |
434 | */ | |
435 | if (!(torture_random(trsp) % | |
436 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) | |
437 | mdelay(longdelay_ms); | |
438 | if (!(torture_random(trsp) % | |
439 | (cxt.nrealwriters_stress * 2 * shortdelay_us))) | |
440 | udelay(shortdelay_us); | |
441 | #ifdef CONFIG_PREEMPT | |
442 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) | |
443 | preempt_schedule(); /* Allow test to be preempted. */ | |
444 | #endif | |
445 | } | |
446 | ||
447 | static void torture_rtmutex_unlock(void) __releases(torture_rtmutex) | |
448 | { | |
449 | rt_mutex_unlock(&torture_rtmutex); | |
450 | } | |
451 | ||
452 | static struct lock_torture_ops rtmutex_lock_ops = { | |
453 | .writelock = torture_rtmutex_lock, | |
454 | .write_delay = torture_rtmutex_delay, | |
455 | .task_boost = torture_rtmutex_boost, | |
456 | .writeunlock = torture_rtmutex_unlock, | |
457 | .readlock = NULL, | |
458 | .read_delay = NULL, | |
459 | .readunlock = NULL, | |
460 | .name = "rtmutex_lock" | |
461 | }; | |
462 | #endif | |
463 | ||
4a3b427f DB |
464 | static DECLARE_RWSEM(torture_rwsem); |
465 | static int torture_rwsem_down_write(void) __acquires(torture_rwsem) | |
466 | { | |
467 | down_write(&torture_rwsem); | |
468 | return 0; | |
469 | } | |
470 | ||
471 | static void torture_rwsem_write_delay(struct torture_random_state *trsp) | |
472 | { | |
473 | const unsigned long longdelay_ms = 100; | |
474 | ||
475 | /* We want a long delay occasionally to force massive contention. */ | |
476 | if (!(torture_random(trsp) % | |
630952c2 | 477 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
4a3b427f DB |
478 | mdelay(longdelay_ms * 10); |
479 | else | |
480 | mdelay(longdelay_ms / 10); | |
481 | #ifdef CONFIG_PREEMPT | |
630952c2 | 482 | if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) |
4a3b427f DB |
483 | preempt_schedule(); /* Allow test to be preempted. */ |
484 | #endif | |
485 | } | |
486 | ||
487 | static void torture_rwsem_up_write(void) __releases(torture_rwsem) | |
488 | { | |
489 | up_write(&torture_rwsem); | |
490 | } | |
491 | ||
492 | static int torture_rwsem_down_read(void) __acquires(torture_rwsem) | |
493 | { | |
494 | down_read(&torture_rwsem); | |
495 | return 0; | |
496 | } | |
497 | ||
498 | static void torture_rwsem_read_delay(struct torture_random_state *trsp) | |
499 | { | |
500 | const unsigned long longdelay_ms = 100; | |
501 | ||
502 | /* We want a long delay occasionally to force massive contention. */ | |
503 | if (!(torture_random(trsp) % | |
630952c2 | 504 | (cxt.nrealwriters_stress * 2000 * longdelay_ms))) |
4a3b427f DB |
505 | mdelay(longdelay_ms * 2); |
506 | else | |
507 | mdelay(longdelay_ms / 2); | |
508 | #ifdef CONFIG_PREEMPT | |
630952c2 | 509 | if (!(torture_random(trsp) % (cxt.nrealreaders_stress * 20000))) |
4a3b427f DB |
510 | preempt_schedule(); /* Allow test to be preempted. */ |
511 | #endif | |
512 | } | |
513 | ||
514 | static void torture_rwsem_up_read(void) __releases(torture_rwsem) | |
515 | { | |
516 | up_read(&torture_rwsem); | |
517 | } | |
518 | ||
519 | static struct lock_torture_ops rwsem_lock_ops = { | |
520 | .writelock = torture_rwsem_down_write, | |
521 | .write_delay = torture_rwsem_write_delay, | |
095777c4 | 522 | .task_boost = torture_boost_dummy, |
4a3b427f DB |
523 | .writeunlock = torture_rwsem_up_write, |
524 | .readlock = torture_rwsem_down_read, | |
525 | .read_delay = torture_rwsem_read_delay, | |
526 | .readunlock = torture_rwsem_up_read, | |
527 | .name = "rwsem_lock" | |
528 | }; | |
529 | ||
617783dd PM |
530 | #include <linux/percpu-rwsem.h> |
531 | static struct percpu_rw_semaphore pcpu_rwsem; | |
532 | ||
533 | void torture_percpu_rwsem_init(void) | |
534 | { | |
535 | BUG_ON(percpu_init_rwsem(&pcpu_rwsem)); | |
536 | } | |
537 | ||
538 | static int torture_percpu_rwsem_down_write(void) __acquires(pcpu_rwsem) | |
539 | { | |
540 | percpu_down_write(&pcpu_rwsem); | |
541 | return 0; | |
542 | } | |
543 | ||
544 | static void torture_percpu_rwsem_up_write(void) __releases(pcpu_rwsem) | |
545 | { | |
546 | percpu_up_write(&pcpu_rwsem); | |
547 | } | |
548 | ||
549 | static int torture_percpu_rwsem_down_read(void) __acquires(pcpu_rwsem) | |
550 | { | |
551 | percpu_down_read(&pcpu_rwsem); | |
552 | return 0; | |
553 | } | |
554 | ||
555 | static void torture_percpu_rwsem_up_read(void) __releases(pcpu_rwsem) | |
556 | { | |
557 | percpu_up_read(&pcpu_rwsem); | |
558 | } | |
559 | ||
560 | static struct lock_torture_ops percpu_rwsem_lock_ops = { | |
561 | .init = torture_percpu_rwsem_init, | |
562 | .writelock = torture_percpu_rwsem_down_write, | |
563 | .write_delay = torture_rwsem_write_delay, | |
564 | .task_boost = torture_boost_dummy, | |
565 | .writeunlock = torture_percpu_rwsem_up_write, | |
566 | .readlock = torture_percpu_rwsem_down_read, | |
567 | .read_delay = torture_rwsem_read_delay, | |
568 | .readunlock = torture_percpu_rwsem_up_read, | |
569 | .name = "percpu_rwsem_lock" | |
570 | }; | |
571 | ||
0af3fe1e PM |
572 | /* |
573 | * Lock torture writer kthread. Repeatedly acquires and releases | |
574 | * the lock, checking for duplicate acquisitions. | |
575 | */ | |
576 | static int lock_torture_writer(void *arg) | |
577 | { | |
1e6757a9 | 578 | struct lock_stress_stats *lwsp = arg; |
0af3fe1e PM |
579 | static DEFINE_TORTURE_RANDOM(rand); |
580 | ||
581 | VERBOSE_TOROUT_STRING("lock_torture_writer task started"); | |
8698a745 | 582 | set_user_nice(current, MAX_NICE); |
0af3fe1e PM |
583 | |
584 | do { | |
da601c63 PM |
585 | if ((torture_random(&rand) & 0xfffff) == 0) |
586 | schedule_timeout_uninterruptible(1); | |
a1229491 | 587 | |
095777c4 | 588 | cxt.cur_ops->task_boost(&rand); |
630952c2 | 589 | cxt.cur_ops->writelock(); |
0af3fe1e | 590 | if (WARN_ON_ONCE(lock_is_write_held)) |
1e6757a9 | 591 | lwsp->n_lock_fail++; |
0af3fe1e | 592 | lock_is_write_held = 1; |
a1229491 DB |
593 | if (WARN_ON_ONCE(lock_is_read_held)) |
594 | lwsp->n_lock_fail++; /* rare, but... */ | |
595 | ||
1e6757a9 | 596 | lwsp->n_lock_acquired++; |
630952c2 | 597 | cxt.cur_ops->write_delay(&rand); |
0af3fe1e | 598 | lock_is_write_held = 0; |
630952c2 | 599 | cxt.cur_ops->writeunlock(); |
a1229491 | 600 | |
0af3fe1e PM |
601 | stutter_wait("lock_torture_writer"); |
602 | } while (!torture_must_stop()); | |
095777c4 DB |
603 | |
604 | cxt.cur_ops->task_boost(NULL); /* reset prio */ | |
0af3fe1e PM |
605 | torture_kthread_stopping("lock_torture_writer"); |
606 | return 0; | |
607 | } | |
608 | ||
4f6332c1 DB |
609 | /* |
610 | * Lock torture reader kthread. Repeatedly acquires and releases | |
611 | * the reader lock. | |
612 | */ | |
613 | static int lock_torture_reader(void *arg) | |
614 | { | |
615 | struct lock_stress_stats *lrsp = arg; | |
616 | static DEFINE_TORTURE_RANDOM(rand); | |
617 | ||
618 | VERBOSE_TOROUT_STRING("lock_torture_reader task started"); | |
619 | set_user_nice(current, MAX_NICE); | |
620 | ||
621 | do { | |
622 | if ((torture_random(&rand) & 0xfffff) == 0) | |
623 | schedule_timeout_uninterruptible(1); | |
a1229491 | 624 | |
630952c2 | 625 | cxt.cur_ops->readlock(); |
4f6332c1 | 626 | lock_is_read_held = 1; |
a1229491 DB |
627 | if (WARN_ON_ONCE(lock_is_write_held)) |
628 | lrsp->n_lock_fail++; /* rare, but... */ | |
629 | ||
4f6332c1 | 630 | lrsp->n_lock_acquired++; |
630952c2 | 631 | cxt.cur_ops->read_delay(&rand); |
4f6332c1 | 632 | lock_is_read_held = 0; |
630952c2 | 633 | cxt.cur_ops->readunlock(); |
a1229491 | 634 | |
4f6332c1 DB |
635 | stutter_wait("lock_torture_reader"); |
636 | } while (!torture_must_stop()); | |
637 | torture_kthread_stopping("lock_torture_reader"); | |
638 | return 0; | |
639 | } | |
640 | ||
0af3fe1e PM |
641 | /* |
642 | * Create an lock-torture-statistics message in the specified buffer. | |
643 | */ | |
4f6332c1 DB |
644 | static void __torture_print_stats(char *page, |
645 | struct lock_stress_stats *statp, bool write) | |
0af3fe1e PM |
646 | { |
647 | bool fail = 0; | |
4f6332c1 | 648 | int i, n_stress; |
0af3fe1e | 649 | long max = 0; |
4f6332c1 | 650 | long min = statp[0].n_lock_acquired; |
0af3fe1e PM |
651 | long long sum = 0; |
652 | ||
630952c2 | 653 | n_stress = write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress; |
4f6332c1 DB |
654 | for (i = 0; i < n_stress; i++) { |
655 | if (statp[i].n_lock_fail) | |
0af3fe1e | 656 | fail = true; |
4f6332c1 DB |
657 | sum += statp[i].n_lock_acquired; |
658 | if (max < statp[i].n_lock_fail) | |
659 | max = statp[i].n_lock_fail; | |
660 | if (min > statp[i].n_lock_fail) | |
661 | min = statp[i].n_lock_fail; | |
0af3fe1e | 662 | } |
0af3fe1e | 663 | page += sprintf(page, |
4f6332c1 DB |
664 | "%s: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n", |
665 | write ? "Writes" : "Reads ", | |
0af3fe1e PM |
666 | sum, max, min, max / 2 > min ? "???" : "", |
667 | fail, fail ? "!!!" : ""); | |
668 | if (fail) | |
630952c2 | 669 | atomic_inc(&cxt.n_lock_torture_errors); |
0af3fe1e PM |
670 | } |
671 | ||
672 | /* | |
673 | * Print torture statistics. Caller must ensure that there is only one | |
674 | * call to this function at a given time!!! This is normally accomplished | |
675 | * by relying on the module system to only have one copy of the module | |
676 | * loaded, and then by giving the lock_torture_stats kthread full control | |
677 | * (or the init/cleanup functions when lock_torture_stats thread is not | |
678 | * running). | |
679 | */ | |
680 | static void lock_torture_stats_print(void) | |
681 | { | |
630952c2 | 682 | int size = cxt.nrealwriters_stress * 200 + 8192; |
0af3fe1e PM |
683 | char *buf; |
684 | ||
630952c2 DB |
685 | if (cxt.cur_ops->readlock) |
686 | size += cxt.nrealreaders_stress * 200 + 8192; | |
4f6332c1 | 687 | |
0af3fe1e PM |
688 | buf = kmalloc(size, GFP_KERNEL); |
689 | if (!buf) { | |
690 | pr_err("lock_torture_stats_print: Out of memory, need: %d", | |
691 | size); | |
692 | return; | |
693 | } | |
4f6332c1 | 694 | |
630952c2 | 695 | __torture_print_stats(buf, cxt.lwsa, true); |
0af3fe1e PM |
696 | pr_alert("%s", buf); |
697 | kfree(buf); | |
4f6332c1 | 698 | |
630952c2 | 699 | if (cxt.cur_ops->readlock) { |
4f6332c1 DB |
700 | buf = kmalloc(size, GFP_KERNEL); |
701 | if (!buf) { | |
702 | pr_err("lock_torture_stats_print: Out of memory, need: %d", | |
703 | size); | |
704 | return; | |
705 | } | |
706 | ||
630952c2 | 707 | __torture_print_stats(buf, cxt.lrsa, false); |
4f6332c1 DB |
708 | pr_alert("%s", buf); |
709 | kfree(buf); | |
710 | } | |
0af3fe1e PM |
711 | } |
712 | ||
713 | /* | |
714 | * Periodically prints torture statistics, if periodic statistics printing | |
715 | * was specified via the stat_interval module parameter. | |
716 | * | |
717 | * No need to worry about fullstop here, since this one doesn't reference | |
718 | * volatile state or register callbacks. | |
719 | */ | |
720 | static int lock_torture_stats(void *arg) | |
721 | { | |
722 | VERBOSE_TOROUT_STRING("lock_torture_stats task started"); | |
723 | do { | |
724 | schedule_timeout_interruptible(stat_interval * HZ); | |
725 | lock_torture_stats_print(); | |
726 | torture_shutdown_absorb("lock_torture_stats"); | |
727 | } while (!torture_must_stop()); | |
728 | torture_kthread_stopping("lock_torture_stats"); | |
729 | return 0; | |
730 | } | |
731 | ||
732 | static inline void | |
733 | lock_torture_print_module_parms(struct lock_torture_ops *cur_ops, | |
734 | const char *tag) | |
735 | { | |
736 | pr_alert("%s" TORTURE_FLAG | |
4f6332c1 | 737 | "--- %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 |
738 | torture_type, tag, cxt.debug_lock ? " [debug]": "", |
739 | cxt.nrealwriters_stress, cxt.nrealreaders_stress, stat_interval, | |
4f6332c1 | 740 | verbose, shuffle_interval, stutter, shutdown_secs, |
0af3fe1e PM |
741 | onoff_interval, onoff_holdoff); |
742 | } | |
743 | ||
744 | static void lock_torture_cleanup(void) | |
745 | { | |
746 | int i; | |
747 | ||
d36a7a0d | 748 | if (torture_cleanup_begin()) |
0af3fe1e PM |
749 | return; |
750 | ||
751 | if (writer_tasks) { | |
630952c2 | 752 | for (i = 0; i < cxt.nrealwriters_stress; i++) |
0af3fe1e PM |
753 | torture_stop_kthread(lock_torture_writer, |
754 | writer_tasks[i]); | |
755 | kfree(writer_tasks); | |
756 | writer_tasks = NULL; | |
757 | } | |
758 | ||
4f6332c1 | 759 | if (reader_tasks) { |
630952c2 | 760 | for (i = 0; i < cxt.nrealreaders_stress; i++) |
4f6332c1 DB |
761 | torture_stop_kthread(lock_torture_reader, |
762 | reader_tasks[i]); | |
763 | kfree(reader_tasks); | |
764 | reader_tasks = NULL; | |
765 | } | |
766 | ||
0af3fe1e PM |
767 | torture_stop_kthread(lock_torture_stats, stats_task); |
768 | lock_torture_stats_print(); /* -After- the stats thread is stopped! */ | |
769 | ||
630952c2 DB |
770 | if (atomic_read(&cxt.n_lock_torture_errors)) |
771 | lock_torture_print_module_parms(cxt.cur_ops, | |
0af3fe1e PM |
772 | "End of test: FAILURE"); |
773 | else if (torture_onoff_failures()) | |
630952c2 | 774 | lock_torture_print_module_parms(cxt.cur_ops, |
0af3fe1e PM |
775 | "End of test: LOCK_HOTPLUG"); |
776 | else | |
630952c2 | 777 | lock_torture_print_module_parms(cxt.cur_ops, |
0af3fe1e | 778 | "End of test: SUCCESS"); |
d36a7a0d | 779 | torture_cleanup_end(); |
0af3fe1e PM |
780 | } |
781 | ||
782 | static int __init lock_torture_init(void) | |
783 | { | |
4f6332c1 | 784 | int i, j; |
0af3fe1e PM |
785 | int firsterr = 0; |
786 | static struct lock_torture_ops *torture_ops[] = { | |
e34191fa DB |
787 | &lock_busted_ops, |
788 | &spin_lock_ops, &spin_lock_irq_ops, | |
789 | &rw_lock_ops, &rw_lock_irq_ops, | |
790 | &mutex_lock_ops, | |
095777c4 DB |
791 | #ifdef CONFIG_RT_MUTEXES |
792 | &rtmutex_lock_ops, | |
793 | #endif | |
e34191fa | 794 | &rwsem_lock_ops, |
617783dd | 795 | &percpu_rwsem_lock_ops, |
0af3fe1e PM |
796 | }; |
797 | ||
23a8e5c2 | 798 | if (!torture_init_begin(torture_type, verbose, &torture_runnable)) |
5228084e | 799 | return -EBUSY; |
0af3fe1e PM |
800 | |
801 | /* Process args and tell the world that the torturer is on the job. */ | |
802 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { | |
630952c2 DB |
803 | cxt.cur_ops = torture_ops[i]; |
804 | if (strcmp(torture_type, cxt.cur_ops->name) == 0) | |
0af3fe1e PM |
805 | break; |
806 | } | |
807 | if (i == ARRAY_SIZE(torture_ops)) { | |
808 | pr_alert("lock-torture: invalid torture type: \"%s\"\n", | |
809 | torture_type); | |
810 | pr_alert("lock-torture types:"); | |
811 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
812 | pr_alert(" %s", torture_ops[i]->name); | |
813 | pr_alert("\n"); | |
a36a9961 PM |
814 | firsterr = -EINVAL; |
815 | goto unwind; | |
0af3fe1e | 816 | } |
630952c2 | 817 | if (cxt.cur_ops->init) |
a36a9961 | 818 | cxt.cur_ops->init(); |
0af3fe1e PM |
819 | |
820 | if (nwriters_stress >= 0) | |
630952c2 | 821 | cxt.nrealwriters_stress = nwriters_stress; |
0af3fe1e | 822 | else |
630952c2 | 823 | cxt.nrealwriters_stress = 2 * num_online_cpus(); |
f095bfc0 DB |
824 | |
825 | #ifdef CONFIG_DEBUG_MUTEXES | |
826 | if (strncmp(torture_type, "mutex", 5) == 0) | |
630952c2 | 827 | cxt.debug_lock = true; |
f095bfc0 | 828 | #endif |
095777c4 DB |
829 | #ifdef CONFIG_DEBUG_RT_MUTEXES |
830 | if (strncmp(torture_type, "rtmutex", 7) == 0) | |
831 | cxt.debug_lock = true; | |
832 | #endif | |
f095bfc0 | 833 | #ifdef CONFIG_DEBUG_SPINLOCK |
e34191fa DB |
834 | if ((strncmp(torture_type, "spin", 4) == 0) || |
835 | (strncmp(torture_type, "rw_lock", 7) == 0)) | |
630952c2 | 836 | cxt.debug_lock = true; |
f095bfc0 | 837 | #endif |
0af3fe1e PM |
838 | |
839 | /* Initialize the statistics so that each run gets its own numbers. */ | |
840 | ||
841 | lock_is_write_held = 0; | |
630952c2 DB |
842 | cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL); |
843 | if (cxt.lwsa == NULL) { | |
844 | VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory"); | |
0af3fe1e PM |
845 | firsterr = -ENOMEM; |
846 | goto unwind; | |
847 | } | |
630952c2 DB |
848 | for (i = 0; i < cxt.nrealwriters_stress; i++) { |
849 | cxt.lwsa[i].n_lock_fail = 0; | |
850 | cxt.lwsa[i].n_lock_acquired = 0; | |
0af3fe1e PM |
851 | } |
852 | ||
630952c2 | 853 | if (cxt.cur_ops->readlock) { |
4f6332c1 | 854 | if (nreaders_stress >= 0) |
630952c2 | 855 | cxt.nrealreaders_stress = nreaders_stress; |
4f6332c1 DB |
856 | else { |
857 | /* | |
858 | * By default distribute evenly the number of | |
859 | * readers and writers. We still run the same number | |
860 | * of threads as the writer-only locks default. | |
861 | */ | |
862 | if (nwriters_stress < 0) /* user doesn't care */ | |
630952c2 DB |
863 | cxt.nrealwriters_stress = num_online_cpus(); |
864 | cxt.nrealreaders_stress = cxt.nrealwriters_stress; | |
4f6332c1 DB |
865 | } |
866 | ||
867 | lock_is_read_held = 0; | |
630952c2 DB |
868 | cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL); |
869 | if (cxt.lrsa == NULL) { | |
870 | VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); | |
4f6332c1 | 871 | firsterr = -ENOMEM; |
630952c2 | 872 | kfree(cxt.lwsa); |
4f6332c1 DB |
873 | goto unwind; |
874 | } | |
0af3fe1e | 875 | |
630952c2 DB |
876 | for (i = 0; i < cxt.nrealreaders_stress; i++) { |
877 | cxt.lrsa[i].n_lock_fail = 0; | |
878 | cxt.lrsa[i].n_lock_acquired = 0; | |
4f6332c1 DB |
879 | } |
880 | } | |
630952c2 | 881 | lock_torture_print_module_parms(cxt.cur_ops, "Start of test"); |
4f6332c1 DB |
882 | |
883 | /* Prepare torture context. */ | |
0af3fe1e PM |
884 | if (onoff_interval > 0) { |
885 | firsterr = torture_onoff_init(onoff_holdoff * HZ, | |
886 | onoff_interval * HZ); | |
887 | if (firsterr) | |
888 | goto unwind; | |
889 | } | |
890 | if (shuffle_interval > 0) { | |
891 | firsterr = torture_shuffle_init(shuffle_interval); | |
892 | if (firsterr) | |
893 | goto unwind; | |
894 | } | |
895 | if (shutdown_secs > 0) { | |
896 | firsterr = torture_shutdown_init(shutdown_secs, | |
897 | lock_torture_cleanup); | |
898 | if (firsterr) | |
899 | goto unwind; | |
900 | } | |
901 | if (stutter > 0) { | |
902 | firsterr = torture_stutter_init(stutter); | |
903 | if (firsterr) | |
904 | goto unwind; | |
905 | } | |
906 | ||
630952c2 | 907 | writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]), |
0af3fe1e PM |
908 | GFP_KERNEL); |
909 | if (writer_tasks == NULL) { | |
910 | VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); | |
911 | firsterr = -ENOMEM; | |
912 | goto unwind; | |
913 | } | |
4f6332c1 | 914 | |
630952c2 DB |
915 | if (cxt.cur_ops->readlock) { |
916 | reader_tasks = kzalloc(cxt.nrealreaders_stress * sizeof(reader_tasks[0]), | |
4f6332c1 DB |
917 | GFP_KERNEL); |
918 | if (reader_tasks == NULL) { | |
919 | VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory"); | |
920 | firsterr = -ENOMEM; | |
921 | goto unwind; | |
922 | } | |
923 | } | |
924 | ||
925 | /* | |
926 | * Create the kthreads and start torturing (oh, those poor little locks). | |
927 | * | |
928 | * TODO: Note that we interleave writers with readers, giving writers a | |
929 | * slight advantage, by creating its kthread first. This can be modified | |
930 | * for very specific needs, or even let the user choose the policy, if | |
931 | * ever wanted. | |
932 | */ | |
630952c2 DB |
933 | for (i = 0, j = 0; i < cxt.nrealwriters_stress || |
934 | j < cxt.nrealreaders_stress; i++, j++) { | |
935 | if (i >= cxt.nrealwriters_stress) | |
4f6332c1 DB |
936 | goto create_reader; |
937 | ||
938 | /* Create writer. */ | |
630952c2 | 939 | firsterr = torture_create_kthread(lock_torture_writer, &cxt.lwsa[i], |
0af3fe1e PM |
940 | writer_tasks[i]); |
941 | if (firsterr) | |
942 | goto unwind; | |
4f6332c1 DB |
943 | |
944 | create_reader: | |
630952c2 | 945 | if (cxt.cur_ops->readlock == NULL || (j >= cxt.nrealreaders_stress)) |
4f6332c1 DB |
946 | continue; |
947 | /* Create reader. */ | |
630952c2 | 948 | firsterr = torture_create_kthread(lock_torture_reader, &cxt.lrsa[j], |
4f6332c1 DB |
949 | reader_tasks[j]); |
950 | if (firsterr) | |
951 | goto unwind; | |
0af3fe1e PM |
952 | } |
953 | if (stat_interval > 0) { | |
954 | firsterr = torture_create_kthread(lock_torture_stats, NULL, | |
955 | stats_task); | |
956 | if (firsterr) | |
957 | goto unwind; | |
958 | } | |
959 | torture_init_end(); | |
960 | return 0; | |
961 | ||
962 | unwind: | |
963 | torture_init_end(); | |
964 | lock_torture_cleanup(); | |
965 | return firsterr; | |
966 | } | |
967 | ||
968 | module_init(lock_torture_init); | |
969 | module_exit(lock_torture_cleanup); |