Commit | Line | Data |
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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 | * | |
20 | * Author: Paul E. McKenney <paulmck@us.ibm.com> | |
21 | * Based on kernel/rcu/torture.c. | |
22 | */ | |
23 | #include <linux/types.h> | |
24 | #include <linux/kernel.h> | |
25 | #include <linux/init.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/kthread.h> | |
28 | #include <linux/err.h> | |
29 | #include <linux/spinlock.h> | |
42ddc75d | 30 | #include <linux/mutex.h> |
0af3fe1e PM |
31 | #include <linux/smp.h> |
32 | #include <linux/interrupt.h> | |
33 | #include <linux/sched.h> | |
34 | #include <linux/atomic.h> | |
35 | #include <linux/bitops.h> | |
36 | #include <linux/completion.h> | |
37 | #include <linux/moduleparam.h> | |
38 | #include <linux/percpu.h> | |
39 | #include <linux/notifier.h> | |
40 | #include <linux/reboot.h> | |
41 | #include <linux/freezer.h> | |
42 | #include <linux/cpu.h> | |
43 | #include <linux/delay.h> | |
44 | #include <linux/stat.h> | |
45 | #include <linux/slab.h> | |
46 | #include <linux/trace_clock.h> | |
47 | #include <asm/byteorder.h> | |
48 | #include <linux/torture.h> | |
49 | ||
50 | MODULE_LICENSE("GPL"); | |
51 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>"); | |
52 | ||
53 | torture_param(int, nwriters_stress, -1, | |
54 | "Number of write-locking stress-test threads"); | |
4f6332c1 DB |
55 | torture_param(int, nreaders_stress, -1, |
56 | "Number of read-locking stress-test threads"); | |
0af3fe1e PM |
57 | torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); |
58 | torture_param(int, onoff_interval, 0, | |
59 | "Time between CPU hotplugs (s), 0=disable"); | |
60 | torture_param(int, shuffle_interval, 3, | |
61 | "Number of jiffies between shuffles, 0=disable"); | |
62 | torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable."); | |
63 | torture_param(int, stat_interval, 60, | |
64 | "Number of seconds between stats printk()s"); | |
65 | torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable"); | |
66 | torture_param(bool, verbose, true, | |
67 | "Enable verbose debugging printk()s"); | |
68 | ||
f095bfc0 | 69 | static bool debug_lock = false; |
0af3fe1e PM |
70 | static char *torture_type = "spin_lock"; |
71 | module_param(torture_type, charp, 0444); | |
72 | MODULE_PARM_DESC(torture_type, | |
42ddc75d | 73 | "Type of lock to torture (spin_lock, spin_lock_irq, mutex_lock, ...)"); |
0af3fe1e PM |
74 | |
75 | static atomic_t n_lock_torture_errors; | |
76 | ||
77 | static struct task_struct *stats_task; | |
78 | static struct task_struct **writer_tasks; | |
4f6332c1 | 79 | static struct task_struct **reader_tasks; |
0af3fe1e PM |
80 | |
81 | static int nrealwriters_stress; | |
82 | static bool lock_is_write_held; | |
4f6332c1 DB |
83 | static int nrealreaders_stress; |
84 | static bool lock_is_read_held; | |
0af3fe1e | 85 | |
1e6757a9 DB |
86 | struct lock_stress_stats { |
87 | long n_lock_fail; | |
88 | long n_lock_acquired; | |
0af3fe1e | 89 | }; |
1e6757a9 | 90 | static struct lock_stress_stats *lwsa; /* writer statistics */ |
4f6332c1 | 91 | static struct lock_stress_stats *lrsa; /* reader statistics */ |
0af3fe1e | 92 | |
d065eacf | 93 | #if defined(MODULE) |
0af3fe1e PM |
94 | #define LOCKTORTURE_RUNNABLE_INIT 1 |
95 | #else | |
96 | #define LOCKTORTURE_RUNNABLE_INIT 0 | |
97 | #endif | |
23a8e5c2 DB |
98 | int torture_runnable = LOCKTORTURE_RUNNABLE_INIT; |
99 | module_param(torture_runnable, int, 0444); | |
100 | MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init"); | |
0af3fe1e PM |
101 | |
102 | /* Forward reference. */ | |
103 | static void lock_torture_cleanup(void); | |
104 | ||
105 | /* | |
106 | * Operations vector for selecting different types of tests. | |
107 | */ | |
108 | struct lock_torture_ops { | |
109 | void (*init)(void); | |
110 | int (*writelock)(void); | |
111 | void (*write_delay)(struct torture_random_state *trsp); | |
112 | void (*writeunlock)(void); | |
4f6332c1 DB |
113 | int (*readlock)(void); |
114 | void (*read_delay)(struct torture_random_state *trsp); | |
115 | void (*readunlock)(void); | |
0af3fe1e PM |
116 | unsigned long flags; |
117 | const char *name; | |
118 | }; | |
119 | ||
120 | static struct lock_torture_ops *cur_ops; | |
121 | ||
122 | /* | |
123 | * Definitions for lock torture testing. | |
124 | */ | |
125 | ||
e086481b PM |
126 | static int torture_lock_busted_write_lock(void) |
127 | { | |
128 | return 0; /* BUGGY, do not use in real life!!! */ | |
129 | } | |
130 | ||
131 | static void torture_lock_busted_write_delay(struct torture_random_state *trsp) | |
132 | { | |
133 | const unsigned long longdelay_us = 100; | |
134 | ||
135 | /* We want a long delay occasionally to force massive contention. */ | |
136 | if (!(torture_random(trsp) % | |
137 | (nrealwriters_stress * 2000 * longdelay_us))) | |
138 | mdelay(longdelay_us); | |
139 | #ifdef CONFIG_PREEMPT | |
140 | if (!(torture_random(trsp) % (nrealwriters_stress * 20000))) | |
141 | preempt_schedule(); /* Allow test to be preempted. */ | |
142 | #endif | |
143 | } | |
144 | ||
145 | static void torture_lock_busted_write_unlock(void) | |
146 | { | |
147 | /* BUGGY, do not use in real life!!! */ | |
148 | } | |
149 | ||
150 | static struct lock_torture_ops lock_busted_ops = { | |
151 | .writelock = torture_lock_busted_write_lock, | |
152 | .write_delay = torture_lock_busted_write_delay, | |
153 | .writeunlock = torture_lock_busted_write_unlock, | |
4f6332c1 DB |
154 | .readlock = NULL, |
155 | .read_delay = NULL, | |
156 | .readunlock = NULL, | |
e086481b PM |
157 | .name = "lock_busted" |
158 | }; | |
159 | ||
0af3fe1e PM |
160 | static DEFINE_SPINLOCK(torture_spinlock); |
161 | ||
162 | static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock) | |
163 | { | |
164 | spin_lock(&torture_spinlock); | |
165 | return 0; | |
166 | } | |
167 | ||
168 | static void torture_spin_lock_write_delay(struct torture_random_state *trsp) | |
169 | { | |
170 | const unsigned long shortdelay_us = 2; | |
171 | const unsigned long longdelay_us = 100; | |
172 | ||
173 | /* We want a short delay mostly to emulate likely code, and | |
174 | * we want a long delay occasionally to force massive contention. | |
175 | */ | |
176 | if (!(torture_random(trsp) % | |
177 | (nrealwriters_stress * 2000 * longdelay_us))) | |
178 | mdelay(longdelay_us); | |
179 | if (!(torture_random(trsp) % | |
180 | (nrealwriters_stress * 2 * shortdelay_us))) | |
181 | udelay(shortdelay_us); | |
182 | #ifdef CONFIG_PREEMPT | |
183 | if (!(torture_random(trsp) % (nrealwriters_stress * 20000))) | |
184 | preempt_schedule(); /* Allow test to be preempted. */ | |
185 | #endif | |
186 | } | |
187 | ||
188 | static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock) | |
189 | { | |
190 | spin_unlock(&torture_spinlock); | |
191 | } | |
192 | ||
193 | static struct lock_torture_ops spin_lock_ops = { | |
194 | .writelock = torture_spin_lock_write_lock, | |
195 | .write_delay = torture_spin_lock_write_delay, | |
196 | .writeunlock = torture_spin_lock_write_unlock, | |
4f6332c1 DB |
197 | .readlock = NULL, |
198 | .read_delay = NULL, | |
199 | .readunlock = NULL, | |
0af3fe1e PM |
200 | .name = "spin_lock" |
201 | }; | |
202 | ||
203 | static int torture_spin_lock_write_lock_irq(void) | |
204 | __acquires(torture_spinlock_irq) | |
205 | { | |
206 | unsigned long flags; | |
207 | ||
208 | spin_lock_irqsave(&torture_spinlock, flags); | |
209 | cur_ops->flags = flags; | |
210 | return 0; | |
211 | } | |
212 | ||
213 | static void torture_lock_spin_write_unlock_irq(void) | |
214 | __releases(torture_spinlock) | |
215 | { | |
216 | spin_unlock_irqrestore(&torture_spinlock, cur_ops->flags); | |
217 | } | |
218 | ||
219 | static struct lock_torture_ops spin_lock_irq_ops = { | |
220 | .writelock = torture_spin_lock_write_lock_irq, | |
221 | .write_delay = torture_spin_lock_write_delay, | |
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 | ||
42ddc75d DB |
229 | static DEFINE_MUTEX(torture_mutex); |
230 | ||
231 | static int torture_mutex_lock(void) __acquires(torture_mutex) | |
232 | { | |
233 | mutex_lock(&torture_mutex); | |
234 | return 0; | |
235 | } | |
236 | ||
237 | static void torture_mutex_delay(struct torture_random_state *trsp) | |
238 | { | |
239 | const unsigned long longdelay_ms = 100; | |
240 | ||
241 | /* We want a long delay occasionally to force massive contention. */ | |
242 | if (!(torture_random(trsp) % | |
243 | (nrealwriters_stress * 2000 * longdelay_ms))) | |
244 | mdelay(longdelay_ms * 5); | |
245 | else | |
246 | mdelay(longdelay_ms / 5); | |
247 | #ifdef CONFIG_PREEMPT | |
248 | if (!(torture_random(trsp) % (nrealwriters_stress * 20000))) | |
249 | preempt_schedule(); /* Allow test to be preempted. */ | |
250 | #endif | |
251 | } | |
252 | ||
253 | static void torture_mutex_unlock(void) __releases(torture_mutex) | |
254 | { | |
255 | mutex_unlock(&torture_mutex); | |
256 | } | |
257 | ||
258 | static struct lock_torture_ops mutex_lock_ops = { | |
259 | .writelock = torture_mutex_lock, | |
260 | .write_delay = torture_mutex_delay, | |
261 | .writeunlock = torture_mutex_unlock, | |
4f6332c1 DB |
262 | .readlock = NULL, |
263 | .read_delay = NULL, | |
264 | .readunlock = NULL, | |
42ddc75d DB |
265 | .name = "mutex_lock" |
266 | }; | |
267 | ||
0af3fe1e PM |
268 | /* |
269 | * Lock torture writer kthread. Repeatedly acquires and releases | |
270 | * the lock, checking for duplicate acquisitions. | |
271 | */ | |
272 | static int lock_torture_writer(void *arg) | |
273 | { | |
1e6757a9 | 274 | struct lock_stress_stats *lwsp = arg; |
0af3fe1e PM |
275 | static DEFINE_TORTURE_RANDOM(rand); |
276 | ||
277 | VERBOSE_TOROUT_STRING("lock_torture_writer task started"); | |
8698a745 | 278 | set_user_nice(current, MAX_NICE); |
0af3fe1e PM |
279 | |
280 | do { | |
da601c63 PM |
281 | if ((torture_random(&rand) & 0xfffff) == 0) |
282 | schedule_timeout_uninterruptible(1); | |
0af3fe1e PM |
283 | cur_ops->writelock(); |
284 | if (WARN_ON_ONCE(lock_is_write_held)) | |
1e6757a9 | 285 | lwsp->n_lock_fail++; |
0af3fe1e | 286 | lock_is_write_held = 1; |
1e6757a9 | 287 | lwsp->n_lock_acquired++; |
0af3fe1e PM |
288 | cur_ops->write_delay(&rand); |
289 | lock_is_write_held = 0; | |
290 | cur_ops->writeunlock(); | |
291 | stutter_wait("lock_torture_writer"); | |
292 | } while (!torture_must_stop()); | |
293 | torture_kthread_stopping("lock_torture_writer"); | |
294 | return 0; | |
295 | } | |
296 | ||
4f6332c1 DB |
297 | /* |
298 | * Lock torture reader kthread. Repeatedly acquires and releases | |
299 | * the reader lock. | |
300 | */ | |
301 | static int lock_torture_reader(void *arg) | |
302 | { | |
303 | struct lock_stress_stats *lrsp = arg; | |
304 | static DEFINE_TORTURE_RANDOM(rand); | |
305 | ||
306 | VERBOSE_TOROUT_STRING("lock_torture_reader task started"); | |
307 | set_user_nice(current, MAX_NICE); | |
308 | ||
309 | do { | |
310 | if ((torture_random(&rand) & 0xfffff) == 0) | |
311 | schedule_timeout_uninterruptible(1); | |
312 | cur_ops->readlock(); | |
313 | lock_is_read_held = 1; | |
314 | lrsp->n_lock_acquired++; | |
315 | cur_ops->read_delay(&rand); | |
316 | lock_is_read_held = 0; | |
317 | cur_ops->readunlock(); | |
318 | stutter_wait("lock_torture_reader"); | |
319 | } while (!torture_must_stop()); | |
320 | torture_kthread_stopping("lock_torture_reader"); | |
321 | return 0; | |
322 | } | |
323 | ||
0af3fe1e PM |
324 | /* |
325 | * Create an lock-torture-statistics message in the specified buffer. | |
326 | */ | |
4f6332c1 DB |
327 | static void __torture_print_stats(char *page, |
328 | struct lock_stress_stats *statp, bool write) | |
0af3fe1e PM |
329 | { |
330 | bool fail = 0; | |
4f6332c1 | 331 | int i, n_stress; |
0af3fe1e | 332 | long max = 0; |
4f6332c1 | 333 | long min = statp[0].n_lock_acquired; |
0af3fe1e PM |
334 | long long sum = 0; |
335 | ||
4f6332c1 DB |
336 | n_stress = write ? nrealwriters_stress : nrealreaders_stress; |
337 | for (i = 0; i < n_stress; i++) { | |
338 | if (statp[i].n_lock_fail) | |
0af3fe1e | 339 | fail = true; |
4f6332c1 DB |
340 | sum += statp[i].n_lock_acquired; |
341 | if (max < statp[i].n_lock_fail) | |
342 | max = statp[i].n_lock_fail; | |
343 | if (min > statp[i].n_lock_fail) | |
344 | min = statp[i].n_lock_fail; | |
0af3fe1e | 345 | } |
0af3fe1e | 346 | page += sprintf(page, |
4f6332c1 DB |
347 | "%s: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n", |
348 | write ? "Writes" : "Reads ", | |
0af3fe1e PM |
349 | sum, max, min, max / 2 > min ? "???" : "", |
350 | fail, fail ? "!!!" : ""); | |
351 | if (fail) | |
352 | atomic_inc(&n_lock_torture_errors); | |
353 | } | |
354 | ||
355 | /* | |
356 | * Print torture statistics. Caller must ensure that there is only one | |
357 | * call to this function at a given time!!! This is normally accomplished | |
358 | * by relying on the module system to only have one copy of the module | |
359 | * loaded, and then by giving the lock_torture_stats kthread full control | |
360 | * (or the init/cleanup functions when lock_torture_stats thread is not | |
361 | * running). | |
362 | */ | |
363 | static void lock_torture_stats_print(void) | |
364 | { | |
365 | int size = nrealwriters_stress * 200 + 8192; | |
366 | char *buf; | |
367 | ||
4f6332c1 DB |
368 | if (cur_ops->readlock) |
369 | size += nrealreaders_stress * 200 + 8192; | |
370 | ||
0af3fe1e PM |
371 | buf = kmalloc(size, GFP_KERNEL); |
372 | if (!buf) { | |
373 | pr_err("lock_torture_stats_print: Out of memory, need: %d", | |
374 | size); | |
375 | return; | |
376 | } | |
4f6332c1 DB |
377 | |
378 | __torture_print_stats(buf, lwsa, true); | |
0af3fe1e PM |
379 | pr_alert("%s", buf); |
380 | kfree(buf); | |
4f6332c1 DB |
381 | |
382 | if (cur_ops->readlock) { | |
383 | buf = kmalloc(size, GFP_KERNEL); | |
384 | if (!buf) { | |
385 | pr_err("lock_torture_stats_print: Out of memory, need: %d", | |
386 | size); | |
387 | return; | |
388 | } | |
389 | ||
390 | __torture_print_stats(buf, lrsa, false); | |
391 | pr_alert("%s", buf); | |
392 | kfree(buf); | |
393 | } | |
0af3fe1e PM |
394 | } |
395 | ||
396 | /* | |
397 | * Periodically prints torture statistics, if periodic statistics printing | |
398 | * was specified via the stat_interval module parameter. | |
399 | * | |
400 | * No need to worry about fullstop here, since this one doesn't reference | |
401 | * volatile state or register callbacks. | |
402 | */ | |
403 | static int lock_torture_stats(void *arg) | |
404 | { | |
405 | VERBOSE_TOROUT_STRING("lock_torture_stats task started"); | |
406 | do { | |
407 | schedule_timeout_interruptible(stat_interval * HZ); | |
408 | lock_torture_stats_print(); | |
409 | torture_shutdown_absorb("lock_torture_stats"); | |
410 | } while (!torture_must_stop()); | |
411 | torture_kthread_stopping("lock_torture_stats"); | |
412 | return 0; | |
413 | } | |
414 | ||
415 | static inline void | |
416 | lock_torture_print_module_parms(struct lock_torture_ops *cur_ops, | |
417 | const char *tag) | |
418 | { | |
419 | pr_alert("%s" TORTURE_FLAG | |
4f6332c1 | 420 | "--- %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", |
f095bfc0 | 421 | torture_type, tag, debug_lock ? " [debug]": "", |
4f6332c1 DB |
422 | nrealwriters_stress, nrealreaders_stress, stat_interval, |
423 | verbose, shuffle_interval, stutter, shutdown_secs, | |
0af3fe1e PM |
424 | onoff_interval, onoff_holdoff); |
425 | } | |
426 | ||
427 | static void lock_torture_cleanup(void) | |
428 | { | |
429 | int i; | |
430 | ||
d36a7a0d | 431 | if (torture_cleanup_begin()) |
0af3fe1e PM |
432 | return; |
433 | ||
434 | if (writer_tasks) { | |
435 | for (i = 0; i < nrealwriters_stress; i++) | |
436 | torture_stop_kthread(lock_torture_writer, | |
437 | writer_tasks[i]); | |
438 | kfree(writer_tasks); | |
439 | writer_tasks = NULL; | |
440 | } | |
441 | ||
4f6332c1 DB |
442 | if (reader_tasks) { |
443 | for (i = 0; i < nrealreaders_stress; i++) | |
444 | torture_stop_kthread(lock_torture_reader, | |
445 | reader_tasks[i]); | |
446 | kfree(reader_tasks); | |
447 | reader_tasks = NULL; | |
448 | } | |
449 | ||
0af3fe1e PM |
450 | torture_stop_kthread(lock_torture_stats, stats_task); |
451 | lock_torture_stats_print(); /* -After- the stats thread is stopped! */ | |
452 | ||
453 | if (atomic_read(&n_lock_torture_errors)) | |
454 | lock_torture_print_module_parms(cur_ops, | |
455 | "End of test: FAILURE"); | |
456 | else if (torture_onoff_failures()) | |
457 | lock_torture_print_module_parms(cur_ops, | |
458 | "End of test: LOCK_HOTPLUG"); | |
459 | else | |
460 | lock_torture_print_module_parms(cur_ops, | |
461 | "End of test: SUCCESS"); | |
d36a7a0d | 462 | torture_cleanup_end(); |
0af3fe1e PM |
463 | } |
464 | ||
465 | static int __init lock_torture_init(void) | |
466 | { | |
4f6332c1 | 467 | int i, j; |
0af3fe1e PM |
468 | int firsterr = 0; |
469 | static struct lock_torture_ops *torture_ops[] = { | |
42ddc75d | 470 | &lock_busted_ops, &spin_lock_ops, &spin_lock_irq_ops, &mutex_lock_ops, |
0af3fe1e PM |
471 | }; |
472 | ||
23a8e5c2 | 473 | if (!torture_init_begin(torture_type, verbose, &torture_runnable)) |
5228084e | 474 | return -EBUSY; |
0af3fe1e PM |
475 | |
476 | /* Process args and tell the world that the torturer is on the job. */ | |
477 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { | |
478 | cur_ops = torture_ops[i]; | |
479 | if (strcmp(torture_type, cur_ops->name) == 0) | |
480 | break; | |
481 | } | |
482 | if (i == ARRAY_SIZE(torture_ops)) { | |
483 | pr_alert("lock-torture: invalid torture type: \"%s\"\n", | |
484 | torture_type); | |
485 | pr_alert("lock-torture types:"); | |
486 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
487 | pr_alert(" %s", torture_ops[i]->name); | |
488 | pr_alert("\n"); | |
489 | torture_init_end(); | |
490 | return -EINVAL; | |
491 | } | |
492 | if (cur_ops->init) | |
493 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ | |
494 | ||
495 | if (nwriters_stress >= 0) | |
496 | nrealwriters_stress = nwriters_stress; | |
497 | else | |
498 | nrealwriters_stress = 2 * num_online_cpus(); | |
f095bfc0 DB |
499 | |
500 | #ifdef CONFIG_DEBUG_MUTEXES | |
501 | if (strncmp(torture_type, "mutex", 5) == 0) | |
502 | debug_lock = true; | |
503 | #endif | |
504 | #ifdef CONFIG_DEBUG_SPINLOCK | |
505 | if (strncmp(torture_type, "spin", 4) == 0) | |
506 | debug_lock = true; | |
507 | #endif | |
0af3fe1e PM |
508 | |
509 | /* Initialize the statistics so that each run gets its own numbers. */ | |
510 | ||
511 | lock_is_write_held = 0; | |
512 | lwsa = kmalloc(sizeof(*lwsa) * nrealwriters_stress, GFP_KERNEL); | |
513 | if (lwsa == NULL) { | |
514 | VERBOSE_TOROUT_STRING("lwsa: Out of memory"); | |
515 | firsterr = -ENOMEM; | |
516 | goto unwind; | |
517 | } | |
518 | for (i = 0; i < nrealwriters_stress; i++) { | |
1e6757a9 DB |
519 | lwsa[i].n_lock_fail = 0; |
520 | lwsa[i].n_lock_acquired = 0; | |
0af3fe1e PM |
521 | } |
522 | ||
4f6332c1 DB |
523 | if (cur_ops->readlock) { |
524 | if (nreaders_stress >= 0) | |
525 | nrealreaders_stress = nreaders_stress; | |
526 | else { | |
527 | /* | |
528 | * By default distribute evenly the number of | |
529 | * readers and writers. We still run the same number | |
530 | * of threads as the writer-only locks default. | |
531 | */ | |
532 | if (nwriters_stress < 0) /* user doesn't care */ | |
533 | nrealwriters_stress = num_online_cpus(); | |
534 | nrealreaders_stress = nrealwriters_stress; | |
535 | } | |
536 | ||
537 | lock_is_read_held = 0; | |
538 | lrsa = kmalloc(sizeof(*lrsa) * nrealreaders_stress, GFP_KERNEL); | |
539 | if (lrsa == NULL) { | |
540 | VERBOSE_TOROUT_STRING("lrsa: Out of memory"); | |
541 | firsterr = -ENOMEM; | |
542 | kfree(lwsa); | |
543 | goto unwind; | |
544 | } | |
0af3fe1e | 545 | |
4f6332c1 DB |
546 | for (i = 0; i < nrealreaders_stress; i++) { |
547 | lrsa[i].n_lock_fail = 0; | |
548 | lrsa[i].n_lock_acquired = 0; | |
549 | } | |
550 | } | |
551 | lock_torture_print_module_parms(cur_ops, "Start of test"); | |
552 | ||
553 | /* Prepare torture context. */ | |
0af3fe1e PM |
554 | if (onoff_interval > 0) { |
555 | firsterr = torture_onoff_init(onoff_holdoff * HZ, | |
556 | onoff_interval * HZ); | |
557 | if (firsterr) | |
558 | goto unwind; | |
559 | } | |
560 | if (shuffle_interval > 0) { | |
561 | firsterr = torture_shuffle_init(shuffle_interval); | |
562 | if (firsterr) | |
563 | goto unwind; | |
564 | } | |
565 | if (shutdown_secs > 0) { | |
566 | firsterr = torture_shutdown_init(shutdown_secs, | |
567 | lock_torture_cleanup); | |
568 | if (firsterr) | |
569 | goto unwind; | |
570 | } | |
571 | if (stutter > 0) { | |
572 | firsterr = torture_stutter_init(stutter); | |
573 | if (firsterr) | |
574 | goto unwind; | |
575 | } | |
576 | ||
577 | writer_tasks = kzalloc(nrealwriters_stress * sizeof(writer_tasks[0]), | |
578 | GFP_KERNEL); | |
579 | if (writer_tasks == NULL) { | |
580 | VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); | |
581 | firsterr = -ENOMEM; | |
582 | goto unwind; | |
583 | } | |
4f6332c1 DB |
584 | |
585 | if (cur_ops->readlock) { | |
586 | reader_tasks = kzalloc(nrealreaders_stress * sizeof(reader_tasks[0]), | |
587 | GFP_KERNEL); | |
588 | if (reader_tasks == NULL) { | |
589 | VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory"); | |
590 | firsterr = -ENOMEM; | |
591 | goto unwind; | |
592 | } | |
593 | } | |
594 | ||
595 | /* | |
596 | * Create the kthreads and start torturing (oh, those poor little locks). | |
597 | * | |
598 | * TODO: Note that we interleave writers with readers, giving writers a | |
599 | * slight advantage, by creating its kthread first. This can be modified | |
600 | * for very specific needs, or even let the user choose the policy, if | |
601 | * ever wanted. | |
602 | */ | |
603 | for (i = 0, j = 0; i < nrealwriters_stress || | |
604 | j < nrealreaders_stress; i++, j++) { | |
605 | if (i >= nrealwriters_stress) | |
606 | goto create_reader; | |
607 | ||
608 | /* Create writer. */ | |
0af3fe1e PM |
609 | firsterr = torture_create_kthread(lock_torture_writer, &lwsa[i], |
610 | writer_tasks[i]); | |
611 | if (firsterr) | |
612 | goto unwind; | |
4f6332c1 DB |
613 | |
614 | create_reader: | |
615 | if (cur_ops->readlock == NULL || (j >= nrealreaders_stress)) | |
616 | continue; | |
617 | /* Create reader. */ | |
618 | firsterr = torture_create_kthread(lock_torture_reader, &lrsa[j], | |
619 | reader_tasks[j]); | |
620 | if (firsterr) | |
621 | goto unwind; | |
0af3fe1e PM |
622 | } |
623 | if (stat_interval > 0) { | |
624 | firsterr = torture_create_kthread(lock_torture_stats, NULL, | |
625 | stats_task); | |
626 | if (firsterr) | |
627 | goto unwind; | |
628 | } | |
629 | torture_init_end(); | |
630 | return 0; | |
631 | ||
632 | unwind: | |
633 | torture_init_end(); | |
634 | lock_torture_cleanup(); | |
635 | return firsterr; | |
636 | } | |
637 | ||
638 | module_init(lock_torture_init); | |
639 | module_exit(lock_torture_cleanup); |