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a241ec65 | 1 | /* |
29766f1e | 2 | * Read-Copy Update module-based torture test facility |
a241ec65 PM |
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, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
b772e1dd | 18 | * Copyright (C) IBM Corporation, 2005, 2006 |
a241ec65 PM |
19 | * |
20 | * Authors: Paul E. McKenney <paulmck@us.ibm.com> | |
b772e1dd | 21 | * Josh Triplett <josh@freedesktop.org> |
a241ec65 PM |
22 | * |
23 | * See also: Documentation/RCU/torture.txt | |
24 | */ | |
25 | #include <linux/types.h> | |
26 | #include <linux/kernel.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/kthread.h> | |
30 | #include <linux/err.h> | |
31 | #include <linux/spinlock.h> | |
32 | #include <linux/smp.h> | |
33 | #include <linux/rcupdate.h> | |
34 | #include <linux/interrupt.h> | |
35 | #include <linux/sched.h> | |
36 | #include <asm/atomic.h> | |
37 | #include <linux/bitops.h> | |
a241ec65 PM |
38 | #include <linux/completion.h> |
39 | #include <linux/moduleparam.h> | |
40 | #include <linux/percpu.h> | |
41 | #include <linux/notifier.h> | |
343e9099 | 42 | #include <linux/reboot.h> |
83144186 | 43 | #include <linux/freezer.h> |
a241ec65 | 44 | #include <linux/cpu.h> |
a241ec65 | 45 | #include <linux/delay.h> |
a241ec65 | 46 | #include <linux/stat.h> |
b2896d2e | 47 | #include <linux/srcu.h> |
1aeb272c | 48 | #include <linux/slab.h> |
f07767fd | 49 | #include <asm/byteorder.h> |
a241ec65 PM |
50 | |
51 | MODULE_LICENSE("GPL"); | |
b772e1dd JT |
52 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and " |
53 | "Josh Triplett <josh@freedesktop.org>"); | |
a241ec65 | 54 | |
4802211c | 55 | static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ |
b772e1dd | 56 | static int nfakewriters = 4; /* # fake writer threads */ |
d84f5203 | 57 | static int stat_interval; /* Interval between stats, in seconds. */ |
a241ec65 | 58 | /* Defaults to "only at end of test". */ |
d84f5203 SV |
59 | static int verbose; /* Print more debug info. */ |
60 | static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ | |
d120f65f PM |
61 | static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ |
62 | static int stutter = 5; /* Start/stop testing interval (in sec) */ | |
0729fbf3 | 63 | static int irqreader = 1; /* RCU readers from irq (timers). */ |
20d2e428 | 64 | static char *torture_type = "rcu"; /* What RCU implementation to torture. */ |
a241ec65 | 65 | |
d6ad6711 | 66 | module_param(nreaders, int, 0444); |
a241ec65 | 67 | MODULE_PARM_DESC(nreaders, "Number of RCU reader threads"); |
d6ad6711 | 68 | module_param(nfakewriters, int, 0444); |
b772e1dd | 69 | MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads"); |
d6ad6711 | 70 | module_param(stat_interval, int, 0444); |
a241ec65 | 71 | MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s"); |
d6ad6711 | 72 | module_param(verbose, bool, 0444); |
a241ec65 | 73 | MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s"); |
d6ad6711 | 74 | module_param(test_no_idle_hz, bool, 0444); |
d84f5203 | 75 | MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs"); |
d6ad6711 | 76 | module_param(shuffle_interval, int, 0444); |
d84f5203 | 77 | MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles"); |
d120f65f PM |
78 | module_param(stutter, int, 0444); |
79 | MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test"); | |
0729fbf3 PM |
80 | module_param(irqreader, int, 0444); |
81 | MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers"); | |
d6ad6711 | 82 | module_param(torture_type, charp, 0444); |
b2896d2e | 83 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); |
72e9bb54 PM |
84 | |
85 | #define TORTURE_FLAG "-torture:" | |
a241ec65 | 86 | #define PRINTK_STRING(s) \ |
72e9bb54 | 87 | do { printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 88 | #define VERBOSE_PRINTK_STRING(s) \ |
72e9bb54 | 89 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 90 | #define VERBOSE_PRINTK_ERRSTRING(s) \ |
72e9bb54 | 91 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) |
a241ec65 PM |
92 | |
93 | static char printk_buf[4096]; | |
94 | ||
95 | static int nrealreaders; | |
96 | static struct task_struct *writer_task; | |
b772e1dd | 97 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
98 | static struct task_struct **reader_tasks; |
99 | static struct task_struct *stats_task; | |
d84f5203 | 100 | static struct task_struct *shuffler_task; |
d120f65f | 101 | static struct task_struct *stutter_task; |
a241ec65 PM |
102 | |
103 | #define RCU_TORTURE_PIPE_LEN 10 | |
104 | ||
105 | struct rcu_torture { | |
106 | struct rcu_head rtort_rcu; | |
107 | int rtort_pipe_count; | |
108 | struct list_head rtort_free; | |
996417d2 | 109 | int rtort_mbtest; |
a241ec65 PM |
110 | }; |
111 | ||
a241ec65 PM |
112 | static LIST_HEAD(rcu_torture_freelist); |
113 | static struct rcu_torture *rcu_torture_current = NULL; | |
114 | static long rcu_torture_current_version = 0; | |
115 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; | |
116 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
117 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = | |
118 | { 0 }; | |
119 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = | |
120 | { 0 }; | |
121 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; | |
b2896d2e PM |
122 | static atomic_t n_rcu_torture_alloc; |
123 | static atomic_t n_rcu_torture_alloc_fail; | |
124 | static atomic_t n_rcu_torture_free; | |
125 | static atomic_t n_rcu_torture_mberror; | |
126 | static atomic_t n_rcu_torture_error; | |
0729fbf3 | 127 | static long n_rcu_torture_timers = 0; |
e3033736 | 128 | static struct list_head rcu_torture_removed; |
a241ec65 | 129 | |
d120f65f PM |
130 | static int stutter_pause_test = 0; |
131 | ||
31a72bce PM |
132 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
133 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
134 | #else | |
135 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
136 | #endif | |
137 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
138 | ||
c9d557c1 PM |
139 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
140 | ||
141 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
142 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
143 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
144 | static int fullstop = FULLSTOP_RMMOD; | |
145 | DEFINE_MUTEX(fullstop_mutex); /* Protect fullstop transitions and spawning */ | |
146 | /* of kthreads. */ | |
343e9099 PM |
147 | |
148 | /* | |
c9d557c1 | 149 | * Detect and respond to a system shutdown. |
343e9099 PM |
150 | */ |
151 | static int | |
152 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
153 | unsigned long unused2, void *unused3) | |
154 | { | |
c59ab97e | 155 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 156 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 157 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 PM |
158 | else |
159 | printk(KERN_WARNING /* but going down anyway, so... */ | |
160 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
c59ab97e | 161 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
162 | return NOTIFY_DONE; |
163 | } | |
164 | ||
c9d557c1 PM |
165 | /* |
166 | * Absorb kthreads into a kernel function that won't return, so that | |
167 | * they won't ever access module text or data again. | |
168 | */ | |
169 | static void rcutorture_shutdown_absorb(char *title) | |
170 | { | |
171 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
172 | printk(KERN_NOTICE | |
173 | "rcutorture thread %s parking due to system shutdown\n", | |
174 | title); | |
175 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
176 | } | |
177 | } | |
178 | ||
a241ec65 PM |
179 | /* |
180 | * Allocate an element from the rcu_tortures pool. | |
181 | */ | |
97a41e26 | 182 | static struct rcu_torture * |
a241ec65 PM |
183 | rcu_torture_alloc(void) |
184 | { | |
185 | struct list_head *p; | |
186 | ||
adac1665 | 187 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
188 | if (list_empty(&rcu_torture_freelist)) { |
189 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 190 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
191 | return NULL; |
192 | } | |
193 | atomic_inc(&n_rcu_torture_alloc); | |
194 | p = rcu_torture_freelist.next; | |
195 | list_del_init(p); | |
adac1665 | 196 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
197 | return container_of(p, struct rcu_torture, rtort_free); |
198 | } | |
199 | ||
200 | /* | |
201 | * Free an element to the rcu_tortures pool. | |
202 | */ | |
203 | static void | |
204 | rcu_torture_free(struct rcu_torture *p) | |
205 | { | |
206 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 207 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 208 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 209 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
210 | } |
211 | ||
a241ec65 PM |
212 | struct rcu_random_state { |
213 | unsigned long rrs_state; | |
75cfef32 | 214 | long rrs_count; |
a241ec65 PM |
215 | }; |
216 | ||
217 | #define RCU_RANDOM_MULT 39916801 /* prime */ | |
218 | #define RCU_RANDOM_ADD 479001701 /* prime */ | |
219 | #define RCU_RANDOM_REFRESH 10000 | |
220 | ||
221 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } | |
222 | ||
223 | /* | |
224 | * Crude but fast random-number generator. Uses a linear congruential | |
c17ac855 | 225 | * generator, with occasional help from cpu_clock(). |
a241ec65 | 226 | */ |
75cfef32 | 227 | static unsigned long |
a241ec65 PM |
228 | rcu_random(struct rcu_random_state *rrsp) |
229 | { | |
a241ec65 | 230 | if (--rrsp->rrs_count < 0) { |
c17ac855 PM |
231 | rrsp->rrs_state += |
232 | (unsigned long)cpu_clock(raw_smp_processor_id()); | |
a241ec65 PM |
233 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
234 | } | |
235 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; | |
236 | return swahw32(rrsp->rrs_state); | |
237 | } | |
238 | ||
d120f65f | 239 | static void |
c9d557c1 | 240 | rcu_stutter_wait(char *title) |
d120f65f | 241 | { |
c9d557c1 | 242 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
243 | if (rcutorture_runnable) |
244 | schedule_timeout_interruptible(1); | |
245 | else | |
3ccf79f4 | 246 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 247 | rcutorture_shutdown_absorb(title); |
343e9099 | 248 | } |
d120f65f PM |
249 | } |
250 | ||
72e9bb54 PM |
251 | /* |
252 | * Operations vector for selecting different types of tests. | |
253 | */ | |
254 | ||
255 | struct rcu_torture_ops { | |
256 | void (*init)(void); | |
257 | void (*cleanup)(void); | |
258 | int (*readlock)(void); | |
b2896d2e | 259 | void (*readdelay)(struct rcu_random_state *rrsp); |
72e9bb54 PM |
260 | void (*readunlock)(int idx); |
261 | int (*completed)(void); | |
262 | void (*deferredfree)(struct rcu_torture *p); | |
b772e1dd | 263 | void (*sync)(void); |
2326974d | 264 | void (*cb_barrier)(void); |
72e9bb54 | 265 | int (*stats)(char *page); |
0729fbf3 | 266 | int irqcapable; |
72e9bb54 PM |
267 | char *name; |
268 | }; | |
269 | static struct rcu_torture_ops *cur_ops = NULL; | |
270 | ||
271 | /* | |
272 | * Definitions for rcu torture testing. | |
273 | */ | |
274 | ||
a49a4af7 | 275 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
276 | { |
277 | rcu_read_lock(); | |
278 | return 0; | |
279 | } | |
280 | ||
b2896d2e PM |
281 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
282 | { | |
283 | long delay; | |
284 | const long longdelay = 200; | |
285 | ||
286 | /* We want there to be long-running readers, but not all the time. */ | |
287 | ||
288 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay); | |
289 | if (!delay) | |
290 | udelay(longdelay); | |
291 | } | |
292 | ||
a49a4af7 | 293 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
294 | { |
295 | rcu_read_unlock(); | |
296 | } | |
297 | ||
298 | static int rcu_torture_completed(void) | |
299 | { | |
300 | return rcu_batches_completed(); | |
301 | } | |
302 | ||
303 | static void | |
304 | rcu_torture_cb(struct rcu_head *p) | |
305 | { | |
306 | int i; | |
307 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
308 | ||
c9d557c1 | 309 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
310 | /* Test is ending, just drop callbacks on the floor. */ |
311 | /* The next initialization will pick up the pieces. */ | |
312 | return; | |
313 | } | |
314 | i = rp->rtort_pipe_count; | |
315 | if (i > RCU_TORTURE_PIPE_LEN) | |
316 | i = RCU_TORTURE_PIPE_LEN; | |
317 | atomic_inc(&rcu_torture_wcount[i]); | |
318 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
319 | rp->rtort_mbtest = 0; | |
320 | rcu_torture_free(rp); | |
321 | } else | |
322 | cur_ops->deferredfree(rp); | |
323 | } | |
324 | ||
325 | static void rcu_torture_deferred_free(struct rcu_torture *p) | |
326 | { | |
327 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
328 | } | |
329 | ||
330 | static struct rcu_torture_ops rcu_ops = { | |
331 | .init = NULL, | |
332 | .cleanup = NULL, | |
333 | .readlock = rcu_torture_read_lock, | |
b2896d2e | 334 | .readdelay = rcu_read_delay, |
72e9bb54 PM |
335 | .readunlock = rcu_torture_read_unlock, |
336 | .completed = rcu_torture_completed, | |
337 | .deferredfree = rcu_torture_deferred_free, | |
b772e1dd | 338 | .sync = synchronize_rcu, |
2326974d | 339 | .cb_barrier = rcu_barrier, |
72e9bb54 | 340 | .stats = NULL, |
0729fbf3 | 341 | .irqcapable = 1, |
72e9bb54 PM |
342 | .name = "rcu" |
343 | }; | |
344 | ||
e3033736 JT |
345 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
346 | { | |
347 | int i; | |
348 | struct rcu_torture *rp; | |
349 | struct rcu_torture *rp1; | |
350 | ||
351 | cur_ops->sync(); | |
352 | list_add(&p->rtort_free, &rcu_torture_removed); | |
353 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
354 | i = rp->rtort_pipe_count; | |
355 | if (i > RCU_TORTURE_PIPE_LEN) | |
356 | i = RCU_TORTURE_PIPE_LEN; | |
357 | atomic_inc(&rcu_torture_wcount[i]); | |
358 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
359 | rp->rtort_mbtest = 0; | |
360 | list_del(&rp->rtort_free); | |
361 | rcu_torture_free(rp); | |
362 | } | |
363 | } | |
364 | } | |
365 | ||
366 | static void rcu_sync_torture_init(void) | |
367 | { | |
368 | INIT_LIST_HEAD(&rcu_torture_removed); | |
369 | } | |
370 | ||
20d2e428 JT |
371 | static struct rcu_torture_ops rcu_sync_ops = { |
372 | .init = rcu_sync_torture_init, | |
373 | .cleanup = NULL, | |
374 | .readlock = rcu_torture_read_lock, | |
375 | .readdelay = rcu_read_delay, | |
376 | .readunlock = rcu_torture_read_unlock, | |
377 | .completed = rcu_torture_completed, | |
378 | .deferredfree = rcu_sync_torture_deferred_free, | |
379 | .sync = synchronize_rcu, | |
2326974d | 380 | .cb_barrier = NULL, |
20d2e428 | 381 | .stats = NULL, |
0729fbf3 | 382 | .irqcapable = 1, |
20d2e428 JT |
383 | .name = "rcu_sync" |
384 | }; | |
385 | ||
c32e0660 PM |
386 | /* |
387 | * Definitions for rcu_bh torture testing. | |
388 | */ | |
389 | ||
a49a4af7 | 390 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
391 | { |
392 | rcu_read_lock_bh(); | |
393 | return 0; | |
394 | } | |
395 | ||
a49a4af7 | 396 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
397 | { |
398 | rcu_read_unlock_bh(); | |
399 | } | |
400 | ||
401 | static int rcu_bh_torture_completed(void) | |
402 | { | |
403 | return rcu_batches_completed_bh(); | |
404 | } | |
405 | ||
406 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
407 | { | |
408 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
409 | } | |
410 | ||
b772e1dd JT |
411 | struct rcu_bh_torture_synchronize { |
412 | struct rcu_head head; | |
413 | struct completion completion; | |
414 | }; | |
415 | ||
416 | static void rcu_bh_torture_wakeme_after_cb(struct rcu_head *head) | |
417 | { | |
418 | struct rcu_bh_torture_synchronize *rcu; | |
419 | ||
420 | rcu = container_of(head, struct rcu_bh_torture_synchronize, head); | |
421 | complete(&rcu->completion); | |
422 | } | |
423 | ||
424 | static void rcu_bh_torture_synchronize(void) | |
425 | { | |
426 | struct rcu_bh_torture_synchronize rcu; | |
427 | ||
428 | init_completion(&rcu.completion); | |
429 | call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb); | |
430 | wait_for_completion(&rcu.completion); | |
431 | } | |
432 | ||
c32e0660 PM |
433 | static struct rcu_torture_ops rcu_bh_ops = { |
434 | .init = NULL, | |
435 | .cleanup = NULL, | |
436 | .readlock = rcu_bh_torture_read_lock, | |
b2896d2e | 437 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ |
c32e0660 PM |
438 | .readunlock = rcu_bh_torture_read_unlock, |
439 | .completed = rcu_bh_torture_completed, | |
440 | .deferredfree = rcu_bh_torture_deferred_free, | |
b772e1dd | 441 | .sync = rcu_bh_torture_synchronize, |
2326974d | 442 | .cb_barrier = rcu_barrier_bh, |
c32e0660 | 443 | .stats = NULL, |
0729fbf3 | 444 | .irqcapable = 1, |
c32e0660 PM |
445 | .name = "rcu_bh" |
446 | }; | |
447 | ||
11a14701 JT |
448 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
449 | .init = rcu_sync_torture_init, | |
450 | .cleanup = NULL, | |
451 | .readlock = rcu_bh_torture_read_lock, | |
452 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ | |
453 | .readunlock = rcu_bh_torture_read_unlock, | |
454 | .completed = rcu_bh_torture_completed, | |
455 | .deferredfree = rcu_sync_torture_deferred_free, | |
456 | .sync = rcu_bh_torture_synchronize, | |
2326974d | 457 | .cb_barrier = NULL, |
11a14701 | 458 | .stats = NULL, |
0729fbf3 | 459 | .irqcapable = 1, |
11a14701 JT |
460 | .name = "rcu_bh_sync" |
461 | }; | |
462 | ||
b2896d2e PM |
463 | /* |
464 | * Definitions for srcu torture testing. | |
465 | */ | |
466 | ||
467 | static struct srcu_struct srcu_ctl; | |
b2896d2e PM |
468 | |
469 | static void srcu_torture_init(void) | |
470 | { | |
471 | init_srcu_struct(&srcu_ctl); | |
e3033736 | 472 | rcu_sync_torture_init(); |
b2896d2e PM |
473 | } |
474 | ||
475 | static void srcu_torture_cleanup(void) | |
476 | { | |
477 | synchronize_srcu(&srcu_ctl); | |
478 | cleanup_srcu_struct(&srcu_ctl); | |
479 | } | |
480 | ||
012d3ca8 | 481 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
482 | { |
483 | return srcu_read_lock(&srcu_ctl); | |
484 | } | |
485 | ||
486 | static void srcu_read_delay(struct rcu_random_state *rrsp) | |
487 | { | |
488 | long delay; | |
489 | const long uspertick = 1000000 / HZ; | |
490 | const long longdelay = 10; | |
491 | ||
492 | /* We want there to be long-running readers, but not all the time. */ | |
493 | ||
494 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); | |
495 | if (!delay) | |
496 | schedule_timeout_interruptible(longdelay); | |
497 | } | |
498 | ||
012d3ca8 | 499 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
500 | { |
501 | srcu_read_unlock(&srcu_ctl, idx); | |
502 | } | |
503 | ||
504 | static int srcu_torture_completed(void) | |
505 | { | |
506 | return srcu_batches_completed(&srcu_ctl); | |
507 | } | |
508 | ||
b772e1dd JT |
509 | static void srcu_torture_synchronize(void) |
510 | { | |
511 | synchronize_srcu(&srcu_ctl); | |
512 | } | |
513 | ||
b2896d2e PM |
514 | static int srcu_torture_stats(char *page) |
515 | { | |
516 | int cnt = 0; | |
517 | int cpu; | |
518 | int idx = srcu_ctl.completed & 0x1; | |
519 | ||
520 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", | |
521 | torture_type, TORTURE_FLAG, idx); | |
522 | for_each_possible_cpu(cpu) { | |
523 | cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu, | |
524 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], | |
525 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
526 | } | |
527 | cnt += sprintf(&page[cnt], "\n"); | |
528 | return cnt; | |
529 | } | |
530 | ||
531 | static struct rcu_torture_ops srcu_ops = { | |
532 | .init = srcu_torture_init, | |
533 | .cleanup = srcu_torture_cleanup, | |
534 | .readlock = srcu_torture_read_lock, | |
535 | .readdelay = srcu_read_delay, | |
536 | .readunlock = srcu_torture_read_unlock, | |
537 | .completed = srcu_torture_completed, | |
e3033736 | 538 | .deferredfree = rcu_sync_torture_deferred_free, |
b772e1dd | 539 | .sync = srcu_torture_synchronize, |
2326974d | 540 | .cb_barrier = NULL, |
b2896d2e PM |
541 | .stats = srcu_torture_stats, |
542 | .name = "srcu" | |
543 | }; | |
544 | ||
4b6c2cca JT |
545 | /* |
546 | * Definitions for sched torture testing. | |
547 | */ | |
548 | ||
549 | static int sched_torture_read_lock(void) | |
550 | { | |
551 | preempt_disable(); | |
552 | return 0; | |
553 | } | |
554 | ||
555 | static void sched_torture_read_unlock(int idx) | |
556 | { | |
557 | preempt_enable(); | |
558 | } | |
559 | ||
560 | static int sched_torture_completed(void) | |
561 | { | |
562 | return 0; | |
563 | } | |
564 | ||
2326974d PM |
565 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
566 | { | |
567 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
568 | } | |
569 | ||
4b6c2cca JT |
570 | static void sched_torture_synchronize(void) |
571 | { | |
572 | synchronize_sched(); | |
573 | } | |
574 | ||
575 | static struct rcu_torture_ops sched_ops = { | |
576 | .init = rcu_sync_torture_init, | |
577 | .cleanup = NULL, | |
578 | .readlock = sched_torture_read_lock, | |
579 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ | |
580 | .readunlock = sched_torture_read_unlock, | |
581 | .completed = sched_torture_completed, | |
2326974d | 582 | .deferredfree = rcu_sched_torture_deferred_free, |
4b6c2cca | 583 | .sync = sched_torture_synchronize, |
2326974d | 584 | .cb_barrier = rcu_barrier_sched, |
4b6c2cca | 585 | .stats = NULL, |
0729fbf3 | 586 | .irqcapable = 1, |
4b6c2cca JT |
587 | .name = "sched" |
588 | }; | |
589 | ||
2326974d PM |
590 | static struct rcu_torture_ops sched_ops_sync = { |
591 | .init = rcu_sync_torture_init, | |
592 | .cleanup = NULL, | |
593 | .readlock = sched_torture_read_lock, | |
594 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ | |
595 | .readunlock = sched_torture_read_unlock, | |
596 | .completed = sched_torture_completed, | |
597 | .deferredfree = rcu_sync_torture_deferred_free, | |
598 | .sync = sched_torture_synchronize, | |
599 | .cb_barrier = NULL, | |
600 | .stats = NULL, | |
601 | .name = "sched_sync" | |
602 | }; | |
603 | ||
a241ec65 PM |
604 | /* |
605 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
606 | * for that pointed to by rcu_torture_current, freeing the old structure | |
607 | * after a series of grace periods (the "pipeline"). | |
608 | */ | |
609 | static int | |
610 | rcu_torture_writer(void *arg) | |
611 | { | |
612 | int i; | |
613 | long oldbatch = rcu_batches_completed(); | |
614 | struct rcu_torture *rp; | |
615 | struct rcu_torture *old_rp; | |
616 | static DEFINE_RCU_RANDOM(rand); | |
617 | ||
618 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
619 | set_user_nice(current, 19); |
620 | ||
a241ec65 PM |
621 | do { |
622 | schedule_timeout_uninterruptible(1); | |
a241ec65 PM |
623 | if ((rp = rcu_torture_alloc()) == NULL) |
624 | continue; | |
625 | rp->rtort_pipe_count = 0; | |
626 | udelay(rcu_random(&rand) & 0x3ff); | |
627 | old_rp = rcu_torture_current; | |
996417d2 | 628 | rp->rtort_mbtest = 1; |
a241ec65 PM |
629 | rcu_assign_pointer(rcu_torture_current, rp); |
630 | smp_wmb(); | |
c8e5b163 | 631 | if (old_rp) { |
a241ec65 PM |
632 | i = old_rp->rtort_pipe_count; |
633 | if (i > RCU_TORTURE_PIPE_LEN) | |
634 | i = RCU_TORTURE_PIPE_LEN; | |
635 | atomic_inc(&rcu_torture_wcount[i]); | |
636 | old_rp->rtort_pipe_count++; | |
72e9bb54 | 637 | cur_ops->deferredfree(old_rp); |
a241ec65 PM |
638 | } |
639 | rcu_torture_current_version++; | |
72e9bb54 | 640 | oldbatch = cur_ops->completed(); |
c9d557c1 PM |
641 | rcu_stutter_wait("rcu_torture_writer"); |
642 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 643 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
644 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
645 | while (!kthread_should_stop()) | |
a241ec65 PM |
646 | schedule_timeout_uninterruptible(1); |
647 | return 0; | |
648 | } | |
649 | ||
b772e1dd JT |
650 | /* |
651 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
652 | * delay between calls. | |
653 | */ | |
654 | static int | |
655 | rcu_torture_fakewriter(void *arg) | |
656 | { | |
657 | DEFINE_RCU_RANDOM(rand); | |
658 | ||
659 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
660 | set_user_nice(current, 19); | |
661 | ||
662 | do { | |
663 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); | |
664 | udelay(rcu_random(&rand) & 0x3ff); | |
665 | cur_ops->sync(); | |
c9d557c1 PM |
666 | rcu_stutter_wait("rcu_torture_fakewriter"); |
667 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
668 | |
669 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
670 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
671 | while (!kthread_should_stop()) | |
b772e1dd JT |
672 | schedule_timeout_uninterruptible(1); |
673 | return 0; | |
674 | } | |
675 | ||
0729fbf3 PM |
676 | /* |
677 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
678 | * incrementing the corresponding element of the pipeline array. The | |
679 | * counter in the element should never be greater than 1, otherwise, the | |
680 | * RCU implementation is broken. | |
681 | */ | |
682 | static void rcu_torture_timer(unsigned long unused) | |
683 | { | |
684 | int idx; | |
685 | int completed; | |
686 | static DEFINE_RCU_RANDOM(rand); | |
687 | static DEFINE_SPINLOCK(rand_lock); | |
688 | struct rcu_torture *p; | |
689 | int pipe_count; | |
690 | ||
691 | idx = cur_ops->readlock(); | |
692 | completed = cur_ops->completed(); | |
693 | p = rcu_dereference(rcu_torture_current); | |
694 | if (p == NULL) { | |
695 | /* Leave because rcu_torture_writer is not yet underway */ | |
696 | cur_ops->readunlock(idx); | |
697 | return; | |
698 | } | |
699 | if (p->rtort_mbtest == 0) | |
700 | atomic_inc(&n_rcu_torture_mberror); | |
701 | spin_lock(&rand_lock); | |
702 | cur_ops->readdelay(&rand); | |
703 | n_rcu_torture_timers++; | |
704 | spin_unlock(&rand_lock); | |
705 | preempt_disable(); | |
706 | pipe_count = p->rtort_pipe_count; | |
707 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
708 | /* Should not happen, but... */ | |
709 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
710 | } | |
711 | ++__get_cpu_var(rcu_torture_count)[pipe_count]; | |
712 | completed = cur_ops->completed() - completed; | |
713 | if (completed > RCU_TORTURE_PIPE_LEN) { | |
714 | /* Should not happen, but... */ | |
715 | completed = RCU_TORTURE_PIPE_LEN; | |
716 | } | |
717 | ++__get_cpu_var(rcu_torture_batch)[completed]; | |
718 | preempt_enable(); | |
719 | cur_ops->readunlock(idx); | |
720 | } | |
721 | ||
a241ec65 PM |
722 | /* |
723 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
724 | * incrementing the corresponding element of the pipeline array. The | |
725 | * counter in the element should never be greater than 1, otherwise, the | |
726 | * RCU implementation is broken. | |
727 | */ | |
728 | static int | |
729 | rcu_torture_reader(void *arg) | |
730 | { | |
731 | int completed; | |
72e9bb54 | 732 | int idx; |
a241ec65 PM |
733 | DEFINE_RCU_RANDOM(rand); |
734 | struct rcu_torture *p; | |
735 | int pipe_count; | |
0729fbf3 | 736 | struct timer_list t; |
a241ec65 PM |
737 | |
738 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 739 | set_user_nice(current, 19); |
0729fbf3 PM |
740 | if (irqreader && cur_ops->irqcapable) |
741 | setup_timer_on_stack(&t, rcu_torture_timer, 0); | |
dbdf65b1 | 742 | |
a241ec65 | 743 | do { |
0729fbf3 PM |
744 | if (irqreader && cur_ops->irqcapable) { |
745 | if (!timer_pending(&t)) | |
746 | mod_timer(&t, 1); | |
747 | } | |
72e9bb54 PM |
748 | idx = cur_ops->readlock(); |
749 | completed = cur_ops->completed(); | |
a241ec65 PM |
750 | p = rcu_dereference(rcu_torture_current); |
751 | if (p == NULL) { | |
752 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 753 | cur_ops->readunlock(idx); |
a241ec65 PM |
754 | schedule_timeout_interruptible(HZ); |
755 | continue; | |
756 | } | |
996417d2 PM |
757 | if (p->rtort_mbtest == 0) |
758 | atomic_inc(&n_rcu_torture_mberror); | |
b2896d2e | 759 | cur_ops->readdelay(&rand); |
a241ec65 PM |
760 | preempt_disable(); |
761 | pipe_count = p->rtort_pipe_count; | |
762 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
763 | /* Should not happen, but... */ | |
764 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
765 | } | |
766 | ++__get_cpu_var(rcu_torture_count)[pipe_count]; | |
72e9bb54 | 767 | completed = cur_ops->completed() - completed; |
a241ec65 PM |
768 | if (completed > RCU_TORTURE_PIPE_LEN) { |
769 | /* Should not happen, but... */ | |
770 | completed = RCU_TORTURE_PIPE_LEN; | |
771 | } | |
772 | ++__get_cpu_var(rcu_torture_batch)[completed]; | |
773 | preempt_enable(); | |
72e9bb54 | 774 | cur_ops->readunlock(idx); |
a241ec65 | 775 | schedule(); |
c9d557c1 PM |
776 | rcu_stutter_wait("rcu_torture_reader"); |
777 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 778 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 779 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0729fbf3 PM |
780 | if (irqreader && cur_ops->irqcapable) |
781 | del_timer_sync(&t); | |
c9d557c1 | 782 | while (!kthread_should_stop()) |
a241ec65 PM |
783 | schedule_timeout_uninterruptible(1); |
784 | return 0; | |
785 | } | |
786 | ||
787 | /* | |
788 | * Create an RCU-torture statistics message in the specified buffer. | |
789 | */ | |
790 | static int | |
791 | rcu_torture_printk(char *page) | |
792 | { | |
793 | int cnt = 0; | |
794 | int cpu; | |
795 | int i; | |
796 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
797 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
798 | ||
0a945022 | 799 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
800 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
801 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
802 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
803 | } | |
804 | } | |
805 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
806 | if (pipesummary[i] != 0) | |
807 | break; | |
808 | } | |
72e9bb54 | 809 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 810 | cnt += sprintf(&page[cnt], |
996417d2 | 811 | "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d " |
0729fbf3 | 812 | "rtmbe: %d nt: %ld", |
a241ec65 PM |
813 | rcu_torture_current, |
814 | rcu_torture_current_version, | |
815 | list_empty(&rcu_torture_freelist), | |
816 | atomic_read(&n_rcu_torture_alloc), | |
817 | atomic_read(&n_rcu_torture_alloc_fail), | |
996417d2 | 818 | atomic_read(&n_rcu_torture_free), |
0729fbf3 PM |
819 | atomic_read(&n_rcu_torture_mberror), |
820 | n_rcu_torture_timers); | |
996417d2 PM |
821 | if (atomic_read(&n_rcu_torture_mberror) != 0) |
822 | cnt += sprintf(&page[cnt], " !!!"); | |
72e9bb54 | 823 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
996417d2 | 824 | if (i > 1) { |
a241ec65 | 825 | cnt += sprintf(&page[cnt], "!!! "); |
996417d2 | 826 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 827 | WARN_ON_ONCE(1); |
996417d2 | 828 | } |
a241ec65 PM |
829 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
830 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) | |
831 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); | |
72e9bb54 | 832 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 833 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
72e9bb54 | 834 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
a241ec65 | 835 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
72e9bb54 | 836 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 PM |
837 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
838 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { | |
839 | cnt += sprintf(&page[cnt], " %d", | |
840 | atomic_read(&rcu_torture_wcount[i])); | |
841 | } | |
842 | cnt += sprintf(&page[cnt], "\n"); | |
c8e5b163 | 843 | if (cur_ops->stats) |
72e9bb54 | 844 | cnt += cur_ops->stats(&page[cnt]); |
a241ec65 PM |
845 | return cnt; |
846 | } | |
847 | ||
848 | /* | |
849 | * Print torture statistics. Caller must ensure that there is only | |
850 | * one call to this function at a given time!!! This is normally | |
851 | * accomplished by relying on the module system to only have one copy | |
852 | * of the module loaded, and then by giving the rcu_torture_stats | |
853 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
854 | * thread is not running). | |
855 | */ | |
856 | static void | |
857 | rcu_torture_stats_print(void) | |
858 | { | |
859 | int cnt; | |
860 | ||
861 | cnt = rcu_torture_printk(printk_buf); | |
862 | printk(KERN_ALERT "%s", printk_buf); | |
863 | } | |
864 | ||
865 | /* | |
866 | * Periodically prints torture statistics, if periodic statistics printing | |
867 | * was specified via the stat_interval module parameter. | |
868 | * | |
869 | * No need to worry about fullstop here, since this one doesn't reference | |
870 | * volatile state or register callbacks. | |
871 | */ | |
872 | static int | |
873 | rcu_torture_stats(void *arg) | |
874 | { | |
875 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
876 | do { | |
877 | schedule_timeout_interruptible(stat_interval * HZ); | |
878 | rcu_torture_stats_print(); | |
c9d557c1 PM |
879 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
880 | } while (!kthread_should_stop()); | |
a241ec65 PM |
881 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
882 | return 0; | |
883 | } | |
884 | ||
d84f5203 SV |
885 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
886 | ||
887 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
888 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
889 | */ | |
b2896d2e | 890 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 891 | { |
c9d557c1 | 892 | cpumask_t tmp_mask; |
d84f5203 SV |
893 | int i; |
894 | ||
c9d557c1 | 895 | cpus_setall(tmp_mask); |
86ef5c9a | 896 | get_online_cpus(); |
d84f5203 SV |
897 | |
898 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
899 | if (num_online_cpus() == 1) { |
900 | put_online_cpus(); | |
901 | return; | |
902 | } | |
d84f5203 SV |
903 | |
904 | if (rcu_idle_cpu != -1) | |
c9d557c1 | 905 | cpu_clear(rcu_idle_cpu, tmp_mask); |
d84f5203 | 906 | |
c9d557c1 | 907 | set_cpus_allowed_ptr(current, &tmp_mask); |
d84f5203 | 908 | |
c8e5b163 | 909 | if (reader_tasks) { |
d84f5203 SV |
910 | for (i = 0; i < nrealreaders; i++) |
911 | if (reader_tasks[i]) | |
f70316da | 912 | set_cpus_allowed_ptr(reader_tasks[i], |
c9d557c1 | 913 | &tmp_mask); |
d84f5203 SV |
914 | } |
915 | ||
c8e5b163 | 916 | if (fakewriter_tasks) { |
b772e1dd JT |
917 | for (i = 0; i < nfakewriters; i++) |
918 | if (fakewriter_tasks[i]) | |
f70316da | 919 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
c9d557c1 | 920 | &tmp_mask); |
b772e1dd JT |
921 | } |
922 | ||
d84f5203 | 923 | if (writer_task) |
c9d557c1 | 924 | set_cpus_allowed_ptr(writer_task, &tmp_mask); |
d84f5203 SV |
925 | |
926 | if (stats_task) | |
c9d557c1 | 927 | set_cpus_allowed_ptr(stats_task, &tmp_mask); |
d84f5203 SV |
928 | |
929 | if (rcu_idle_cpu == -1) | |
930 | rcu_idle_cpu = num_online_cpus() - 1; | |
931 | else | |
932 | rcu_idle_cpu--; | |
933 | ||
86ef5c9a | 934 | put_online_cpus(); |
d84f5203 SV |
935 | } |
936 | ||
937 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
938 | * system to become idle at a time and cut off its timer ticks. This is meant | |
939 | * to test the support for such tickless idle CPU in RCU. | |
940 | */ | |
941 | static int | |
942 | rcu_torture_shuffle(void *arg) | |
943 | { | |
944 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
945 | do { | |
946 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
947 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
948 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
949 | } while (!kthread_should_stop()); | |
d84f5203 SV |
950 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
951 | return 0; | |
952 | } | |
953 | ||
d120f65f PM |
954 | /* Cause the rcutorture test to "stutter", starting and stopping all |
955 | * threads periodically. | |
956 | */ | |
957 | static int | |
958 | rcu_torture_stutter(void *arg) | |
959 | { | |
960 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
961 | do { | |
962 | schedule_timeout_interruptible(stutter * HZ); | |
963 | stutter_pause_test = 1; | |
c9d557c1 | 964 | if (!kthread_should_stop()) |
d120f65f PM |
965 | schedule_timeout_interruptible(stutter * HZ); |
966 | stutter_pause_test = 0; | |
c9d557c1 PM |
967 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
968 | } while (!kthread_should_stop()); | |
d120f65f PM |
969 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
970 | return 0; | |
971 | } | |
972 | ||
95c38322 PM |
973 | static inline void |
974 | rcu_torture_print_module_parms(char *tag) | |
975 | { | |
b772e1dd JT |
976 | printk(KERN_ALERT "%s" TORTURE_FLAG |
977 | "--- %s: nreaders=%d nfakewriters=%d " | |
95c38322 | 978 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
0729fbf3 | 979 | "shuffle_interval=%d stutter=%d irqreader=%d\n", |
b772e1dd | 980 | torture_type, tag, nrealreaders, nfakewriters, |
d120f65f | 981 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, |
0729fbf3 | 982 | stutter, irqreader); |
95c38322 PM |
983 | } |
984 | ||
343e9099 PM |
985 | static struct notifier_block rcutorture_nb = { |
986 | .notifier_call = rcutorture_shutdown_notify, | |
987 | }; | |
988 | ||
a241ec65 PM |
989 | static void |
990 | rcu_torture_cleanup(void) | |
991 | { | |
992 | int i; | |
993 | ||
343e9099 | 994 | mutex_lock(&fullstop_mutex); |
c9d557c1 PM |
995 | if (fullstop == FULLSTOP_SHUTDOWN) { |
996 | printk(KERN_WARNING /* but going down anyway, so... */ | |
997 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
343e9099 | 998 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 999 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1000 | if (cur_ops->cb_barrier != NULL) |
1001 | cur_ops->cb_barrier(); | |
1002 | return; | |
1003 | } | |
c9d557c1 | 1004 | fullstop = FULLSTOP_RMMOD; |
343e9099 PM |
1005 | mutex_unlock(&fullstop_mutex); |
1006 | unregister_reboot_notifier(&rcutorture_nb); | |
d120f65f PM |
1007 | if (stutter_task) { |
1008 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1009 | kthread_stop(stutter_task); | |
1010 | } | |
1011 | stutter_task = NULL; | |
c8e5b163 | 1012 | if (shuffler_task) { |
d84f5203 SV |
1013 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1014 | kthread_stop(shuffler_task); | |
1015 | } | |
1016 | shuffler_task = NULL; | |
1017 | ||
c8e5b163 | 1018 | if (writer_task) { |
a241ec65 PM |
1019 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1020 | kthread_stop(writer_task); | |
1021 | } | |
1022 | writer_task = NULL; | |
1023 | ||
c8e5b163 | 1024 | if (reader_tasks) { |
a241ec65 | 1025 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1026 | if (reader_tasks[i]) { |
a241ec65 PM |
1027 | VERBOSE_PRINTK_STRING( |
1028 | "Stopping rcu_torture_reader task"); | |
1029 | kthread_stop(reader_tasks[i]); | |
1030 | } | |
1031 | reader_tasks[i] = NULL; | |
1032 | } | |
1033 | kfree(reader_tasks); | |
1034 | reader_tasks = NULL; | |
1035 | } | |
1036 | rcu_torture_current = NULL; | |
1037 | ||
c8e5b163 | 1038 | if (fakewriter_tasks) { |
b772e1dd | 1039 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1040 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1041 | VERBOSE_PRINTK_STRING( |
1042 | "Stopping rcu_torture_fakewriter task"); | |
1043 | kthread_stop(fakewriter_tasks[i]); | |
1044 | } | |
1045 | fakewriter_tasks[i] = NULL; | |
1046 | } | |
1047 | kfree(fakewriter_tasks); | |
1048 | fakewriter_tasks = NULL; | |
1049 | } | |
1050 | ||
c8e5b163 | 1051 | if (stats_task) { |
a241ec65 PM |
1052 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1053 | kthread_stop(stats_task); | |
1054 | } | |
1055 | stats_task = NULL; | |
1056 | ||
1057 | /* Wait for all RCU callbacks to fire. */ | |
2326974d PM |
1058 | |
1059 | if (cur_ops->cb_barrier != NULL) | |
1060 | cur_ops->cb_barrier(); | |
a241ec65 | 1061 | |
a241ec65 | 1062 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1063 | |
c8e5b163 | 1064 | if (cur_ops->cleanup) |
72e9bb54 | 1065 | cur_ops->cleanup(); |
95c38322 PM |
1066 | if (atomic_read(&n_rcu_torture_error)) |
1067 | rcu_torture_print_module_parms("End of test: FAILURE"); | |
1068 | else | |
1069 | rcu_torture_print_module_parms("End of test: SUCCESS"); | |
a241ec65 PM |
1070 | } |
1071 | ||
6f8bc500 | 1072 | static int __init |
a241ec65 PM |
1073 | rcu_torture_init(void) |
1074 | { | |
1075 | int i; | |
1076 | int cpu; | |
1077 | int firsterr = 0; | |
ade5fb81 JT |
1078 | static struct rcu_torture_ops *torture_ops[] = |
1079 | { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops, | |
2326974d | 1080 | &srcu_ops, &sched_ops, &sched_ops_sync, }; |
a241ec65 | 1081 | |
343e9099 PM |
1082 | mutex_lock(&fullstop_mutex); |
1083 | ||
a241ec65 | 1084 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1085 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1086 | cur_ops = torture_ops[i]; |
ade5fb81 | 1087 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1088 | break; |
72e9bb54 | 1089 | } |
ade5fb81 | 1090 | if (i == ARRAY_SIZE(torture_ops)) { |
72e9bb54 PM |
1091 | printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n", |
1092 | torture_type); | |
343e9099 | 1093 | mutex_unlock(&fullstop_mutex); |
72e9bb54 PM |
1094 | return (-EINVAL); |
1095 | } | |
c8e5b163 | 1096 | if (cur_ops->init) |
72e9bb54 PM |
1097 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1098 | ||
a241ec65 PM |
1099 | if (nreaders >= 0) |
1100 | nrealreaders = nreaders; | |
1101 | else | |
1102 | nrealreaders = 2 * num_online_cpus(); | |
95c38322 | 1103 | rcu_torture_print_module_parms("Start of test"); |
c9d557c1 | 1104 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1105 | |
1106 | /* Set up the freelist. */ | |
1107 | ||
1108 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1109 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1110 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1111 | list_add_tail(&rcu_tortures[i].rtort_free, |
1112 | &rcu_torture_freelist); | |
1113 | } | |
1114 | ||
1115 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1116 | ||
1117 | rcu_torture_current = NULL; | |
1118 | rcu_torture_current_version = 0; | |
1119 | atomic_set(&n_rcu_torture_alloc, 0); | |
1120 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1121 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1122 | atomic_set(&n_rcu_torture_mberror, 0); |
1123 | atomic_set(&n_rcu_torture_error, 0); | |
a241ec65 PM |
1124 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1125 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1126 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1127 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1128 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1129 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1130 | } | |
1131 | } | |
1132 | ||
1133 | /* Start up the kthreads. */ | |
1134 | ||
1135 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
1136 | writer_task = kthread_run(rcu_torture_writer, NULL, | |
1137 | "rcu_torture_writer"); | |
1138 | if (IS_ERR(writer_task)) { | |
1139 | firsterr = PTR_ERR(writer_task); | |
1140 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
1141 | writer_task = NULL; | |
1142 | goto unwind; | |
1143 | } | |
b772e1dd JT |
1144 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
1145 | GFP_KERNEL); | |
1146 | if (fakewriter_tasks == NULL) { | |
1147 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1148 | firsterr = -ENOMEM; | |
1149 | goto unwind; | |
1150 | } | |
1151 | for (i = 0; i < nfakewriters; i++) { | |
1152 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
1153 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
1154 | "rcu_torture_fakewriter"); | |
1155 | if (IS_ERR(fakewriter_tasks[i])) { | |
1156 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
1157 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
1158 | fakewriter_tasks[i] = NULL; | |
1159 | goto unwind; | |
1160 | } | |
1161 | } | |
2860aaba | 1162 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1163 | GFP_KERNEL); |
1164 | if (reader_tasks == NULL) { | |
1165 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1166 | firsterr = -ENOMEM; | |
1167 | goto unwind; | |
1168 | } | |
1169 | for (i = 0; i < nrealreaders; i++) { | |
1170 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
1171 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
1172 | "rcu_torture_reader"); | |
1173 | if (IS_ERR(reader_tasks[i])) { | |
1174 | firsterr = PTR_ERR(reader_tasks[i]); | |
1175 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
1176 | reader_tasks[i] = NULL; | |
1177 | goto unwind; | |
1178 | } | |
1179 | } | |
1180 | if (stat_interval > 0) { | |
1181 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
1182 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
1183 | "rcu_torture_stats"); | |
1184 | if (IS_ERR(stats_task)) { | |
1185 | firsterr = PTR_ERR(stats_task); | |
1186 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
1187 | stats_task = NULL; | |
1188 | goto unwind; | |
1189 | } | |
1190 | } | |
d84f5203 SV |
1191 | if (test_no_idle_hz) { |
1192 | rcu_idle_cpu = num_online_cpus() - 1; | |
1193 | /* Create the shuffler thread */ | |
1194 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
1195 | "rcu_torture_shuffle"); | |
1196 | if (IS_ERR(shuffler_task)) { | |
1197 | firsterr = PTR_ERR(shuffler_task); | |
1198 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
1199 | shuffler_task = NULL; | |
1200 | goto unwind; | |
1201 | } | |
1202 | } | |
d120f65f PM |
1203 | if (stutter < 0) |
1204 | stutter = 0; | |
1205 | if (stutter) { | |
1206 | /* Create the stutter thread */ | |
1207 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
1208 | "rcu_torture_stutter"); | |
1209 | if (IS_ERR(stutter_task)) { | |
1210 | firsterr = PTR_ERR(stutter_task); | |
1211 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
1212 | stutter_task = NULL; | |
1213 | goto unwind; | |
1214 | } | |
1215 | } | |
343e9099 PM |
1216 | register_reboot_notifier(&rcutorture_nb); |
1217 | mutex_unlock(&fullstop_mutex); | |
a241ec65 PM |
1218 | return 0; |
1219 | ||
1220 | unwind: | |
343e9099 | 1221 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1222 | rcu_torture_cleanup(); |
1223 | return firsterr; | |
1224 | } | |
1225 | ||
1226 | module_init(rcu_torture_init); | |
1227 | module_exit(rcu_torture_cleanup); |