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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> | |
a71fca58 | 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 | 52 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and " |
a71fca58 | 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 | 112 | static LIST_HEAD(rcu_torture_freelist); |
a71fca58 PM |
113 | static struct rcu_torture *rcu_torture_current; |
114 | static long rcu_torture_current_version; | |
a241ec65 PM |
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; | |
a71fca58 | 127 | static long n_rcu_torture_timers; |
e3033736 | 128 | static struct list_head rcu_torture_removed; |
73d0a4b1 | 129 | static cpumask_var_t shuffle_tmp_mask; |
a241ec65 | 130 | |
a71fca58 | 131 | static int stutter_pause_test; |
d120f65f | 132 | |
31a72bce PM |
133 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
134 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
135 | #else | |
136 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
137 | #endif | |
138 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
139 | ||
c9d557c1 PM |
140 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
141 | ||
142 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
143 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
144 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
145 | static int fullstop = FULLSTOP_RMMOD; | |
146 | DEFINE_MUTEX(fullstop_mutex); /* Protect fullstop transitions and spawning */ | |
147 | /* of kthreads. */ | |
343e9099 PM |
148 | |
149 | /* | |
c9d557c1 | 150 | * Detect and respond to a system shutdown. |
343e9099 PM |
151 | */ |
152 | static int | |
153 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
154 | unsigned long unused2, void *unused3) | |
155 | { | |
c59ab97e | 156 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 157 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 158 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 PM |
159 | else |
160 | printk(KERN_WARNING /* but going down anyway, so... */ | |
161 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
c59ab97e | 162 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
163 | return NOTIFY_DONE; |
164 | } | |
165 | ||
c9d557c1 PM |
166 | /* |
167 | * Absorb kthreads into a kernel function that won't return, so that | |
168 | * they won't ever access module text or data again. | |
169 | */ | |
170 | static void rcutorture_shutdown_absorb(char *title) | |
171 | { | |
172 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
173 | printk(KERN_NOTICE | |
174 | "rcutorture thread %s parking due to system shutdown\n", | |
175 | title); | |
176 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
177 | } | |
178 | } | |
179 | ||
a241ec65 PM |
180 | /* |
181 | * Allocate an element from the rcu_tortures pool. | |
182 | */ | |
97a41e26 | 183 | static struct rcu_torture * |
a241ec65 PM |
184 | rcu_torture_alloc(void) |
185 | { | |
186 | struct list_head *p; | |
187 | ||
adac1665 | 188 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
189 | if (list_empty(&rcu_torture_freelist)) { |
190 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 191 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
192 | return NULL; |
193 | } | |
194 | atomic_inc(&n_rcu_torture_alloc); | |
195 | p = rcu_torture_freelist.next; | |
196 | list_del_init(p); | |
adac1665 | 197 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
198 | return container_of(p, struct rcu_torture, rtort_free); |
199 | } | |
200 | ||
201 | /* | |
202 | * Free an element to the rcu_tortures pool. | |
203 | */ | |
204 | static void | |
205 | rcu_torture_free(struct rcu_torture *p) | |
206 | { | |
207 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 208 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 209 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 210 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
211 | } |
212 | ||
a241ec65 PM |
213 | struct rcu_random_state { |
214 | unsigned long rrs_state; | |
75cfef32 | 215 | long rrs_count; |
a241ec65 PM |
216 | }; |
217 | ||
218 | #define RCU_RANDOM_MULT 39916801 /* prime */ | |
219 | #define RCU_RANDOM_ADD 479001701 /* prime */ | |
220 | #define RCU_RANDOM_REFRESH 10000 | |
221 | ||
222 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } | |
223 | ||
224 | /* | |
225 | * Crude but fast random-number generator. Uses a linear congruential | |
c17ac855 | 226 | * generator, with occasional help from cpu_clock(). |
a241ec65 | 227 | */ |
75cfef32 | 228 | static unsigned long |
a241ec65 PM |
229 | rcu_random(struct rcu_random_state *rrsp) |
230 | { | |
a241ec65 | 231 | if (--rrsp->rrs_count < 0) { |
c17ac855 PM |
232 | rrsp->rrs_state += |
233 | (unsigned long)cpu_clock(raw_smp_processor_id()); | |
a241ec65 PM |
234 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
235 | } | |
236 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; | |
237 | return swahw32(rrsp->rrs_state); | |
238 | } | |
239 | ||
d120f65f | 240 | static void |
c9d557c1 | 241 | rcu_stutter_wait(char *title) |
d120f65f | 242 | { |
c9d557c1 | 243 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
244 | if (rcutorture_runnable) |
245 | schedule_timeout_interruptible(1); | |
246 | else | |
3ccf79f4 | 247 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 248 | rcutorture_shutdown_absorb(title); |
343e9099 | 249 | } |
d120f65f PM |
250 | } |
251 | ||
72e9bb54 PM |
252 | /* |
253 | * Operations vector for selecting different types of tests. | |
254 | */ | |
255 | ||
256 | struct rcu_torture_ops { | |
257 | void (*init)(void); | |
258 | void (*cleanup)(void); | |
259 | int (*readlock)(void); | |
0acc512c | 260 | void (*read_delay)(struct rcu_random_state *rrsp); |
72e9bb54 PM |
261 | void (*readunlock)(int idx); |
262 | int (*completed)(void); | |
0acc512c | 263 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 264 | void (*sync)(void); |
2326974d | 265 | void (*cb_barrier)(void); |
72e9bb54 | 266 | int (*stats)(char *page); |
0acc512c | 267 | int irq_capable; |
72e9bb54 PM |
268 | char *name; |
269 | }; | |
a71fca58 PM |
270 | |
271 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
272 | |
273 | /* | |
274 | * Definitions for rcu torture testing. | |
275 | */ | |
276 | ||
a49a4af7 | 277 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
278 | { |
279 | rcu_read_lock(); | |
280 | return 0; | |
281 | } | |
282 | ||
b2896d2e PM |
283 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
284 | { | |
b8d57a76 JT |
285 | const unsigned long shortdelay_us = 200; |
286 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 287 | |
b8d57a76 JT |
288 | /* We want a short delay sometimes to make a reader delay the grace |
289 | * period, and we want a long delay occasionally to trigger | |
290 | * force_quiescent_state. */ | |
b2896d2e | 291 | |
b8d57a76 JT |
292 | if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
293 | mdelay(longdelay_ms); | |
294 | if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) | |
295 | udelay(shortdelay_us); | |
b2896d2e PM |
296 | } |
297 | ||
a49a4af7 | 298 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
299 | { |
300 | rcu_read_unlock(); | |
301 | } | |
302 | ||
303 | static int rcu_torture_completed(void) | |
304 | { | |
305 | return rcu_batches_completed(); | |
306 | } | |
307 | ||
308 | static void | |
309 | rcu_torture_cb(struct rcu_head *p) | |
310 | { | |
311 | int i; | |
312 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
313 | ||
c9d557c1 | 314 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
315 | /* Test is ending, just drop callbacks on the floor. */ |
316 | /* The next initialization will pick up the pieces. */ | |
317 | return; | |
318 | } | |
319 | i = rp->rtort_pipe_count; | |
320 | if (i > RCU_TORTURE_PIPE_LEN) | |
321 | i = RCU_TORTURE_PIPE_LEN; | |
322 | atomic_inc(&rcu_torture_wcount[i]); | |
323 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
324 | rp->rtort_mbtest = 0; | |
325 | rcu_torture_free(rp); | |
326 | } else | |
0acc512c | 327 | cur_ops->deferred_free(rp); |
72e9bb54 PM |
328 | } |
329 | ||
330 | static void rcu_torture_deferred_free(struct rcu_torture *p) | |
331 | { | |
332 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
333 | } | |
334 | ||
335 | static struct rcu_torture_ops rcu_ops = { | |
0acc512c PM |
336 | .init = NULL, |
337 | .cleanup = NULL, | |
338 | .readlock = rcu_torture_read_lock, | |
339 | .read_delay = rcu_read_delay, | |
340 | .readunlock = rcu_torture_read_unlock, | |
341 | .completed = rcu_torture_completed, | |
342 | .deferred_free = rcu_torture_deferred_free, | |
343 | .sync = synchronize_rcu, | |
344 | .cb_barrier = rcu_barrier, | |
345 | .stats = NULL, | |
a71fca58 PM |
346 | .irq_capable = 1, |
347 | .name = "rcu" | |
72e9bb54 PM |
348 | }; |
349 | ||
e3033736 JT |
350 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
351 | { | |
352 | int i; | |
353 | struct rcu_torture *rp; | |
354 | struct rcu_torture *rp1; | |
355 | ||
356 | cur_ops->sync(); | |
357 | list_add(&p->rtort_free, &rcu_torture_removed); | |
358 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
359 | i = rp->rtort_pipe_count; | |
360 | if (i > RCU_TORTURE_PIPE_LEN) | |
361 | i = RCU_TORTURE_PIPE_LEN; | |
362 | atomic_inc(&rcu_torture_wcount[i]); | |
363 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
364 | rp->rtort_mbtest = 0; | |
365 | list_del(&rp->rtort_free); | |
366 | rcu_torture_free(rp); | |
367 | } | |
368 | } | |
369 | } | |
370 | ||
371 | static void rcu_sync_torture_init(void) | |
372 | { | |
373 | INIT_LIST_HEAD(&rcu_torture_removed); | |
374 | } | |
375 | ||
20d2e428 | 376 | static struct rcu_torture_ops rcu_sync_ops = { |
0acc512c PM |
377 | .init = rcu_sync_torture_init, |
378 | .cleanup = NULL, | |
379 | .readlock = rcu_torture_read_lock, | |
380 | .read_delay = rcu_read_delay, | |
381 | .readunlock = rcu_torture_read_unlock, | |
382 | .completed = rcu_torture_completed, | |
383 | .deferred_free = rcu_sync_torture_deferred_free, | |
384 | .sync = synchronize_rcu, | |
385 | .cb_barrier = NULL, | |
386 | .stats = NULL, | |
387 | .irq_capable = 1, | |
388 | .name = "rcu_sync" | |
20d2e428 JT |
389 | }; |
390 | ||
c32e0660 PM |
391 | /* |
392 | * Definitions for rcu_bh torture testing. | |
393 | */ | |
394 | ||
a49a4af7 | 395 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
396 | { |
397 | rcu_read_lock_bh(); | |
398 | return 0; | |
399 | } | |
400 | ||
a49a4af7 | 401 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
402 | { |
403 | rcu_read_unlock_bh(); | |
404 | } | |
405 | ||
406 | static int rcu_bh_torture_completed(void) | |
407 | { | |
408 | return rcu_batches_completed_bh(); | |
409 | } | |
410 | ||
411 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
412 | { | |
413 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
414 | } | |
415 | ||
b772e1dd JT |
416 | struct rcu_bh_torture_synchronize { |
417 | struct rcu_head head; | |
418 | struct completion completion; | |
419 | }; | |
420 | ||
421 | static void rcu_bh_torture_wakeme_after_cb(struct rcu_head *head) | |
422 | { | |
423 | struct rcu_bh_torture_synchronize *rcu; | |
424 | ||
425 | rcu = container_of(head, struct rcu_bh_torture_synchronize, head); | |
426 | complete(&rcu->completion); | |
427 | } | |
428 | ||
429 | static void rcu_bh_torture_synchronize(void) | |
430 | { | |
431 | struct rcu_bh_torture_synchronize rcu; | |
432 | ||
433 | init_completion(&rcu.completion); | |
434 | call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb); | |
435 | wait_for_completion(&rcu.completion); | |
436 | } | |
437 | ||
c32e0660 | 438 | static struct rcu_torture_ops rcu_bh_ops = { |
0acc512c PM |
439 | .init = NULL, |
440 | .cleanup = NULL, | |
441 | .readlock = rcu_bh_torture_read_lock, | |
442 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
443 | .readunlock = rcu_bh_torture_read_unlock, | |
444 | .completed = rcu_bh_torture_completed, | |
445 | .deferred_free = rcu_bh_torture_deferred_free, | |
446 | .sync = rcu_bh_torture_synchronize, | |
447 | .cb_barrier = rcu_barrier_bh, | |
448 | .stats = NULL, | |
449 | .irq_capable = 1, | |
450 | .name = "rcu_bh" | |
c32e0660 PM |
451 | }; |
452 | ||
11a14701 | 453 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
0acc512c PM |
454 | .init = rcu_sync_torture_init, |
455 | .cleanup = NULL, | |
456 | .readlock = rcu_bh_torture_read_lock, | |
457 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
458 | .readunlock = rcu_bh_torture_read_unlock, | |
459 | .completed = rcu_bh_torture_completed, | |
460 | .deferred_free = rcu_sync_torture_deferred_free, | |
461 | .sync = rcu_bh_torture_synchronize, | |
462 | .cb_barrier = NULL, | |
463 | .stats = NULL, | |
464 | .irq_capable = 1, | |
465 | .name = "rcu_bh_sync" | |
11a14701 JT |
466 | }; |
467 | ||
b2896d2e PM |
468 | /* |
469 | * Definitions for srcu torture testing. | |
470 | */ | |
471 | ||
472 | static struct srcu_struct srcu_ctl; | |
b2896d2e PM |
473 | |
474 | static void srcu_torture_init(void) | |
475 | { | |
476 | init_srcu_struct(&srcu_ctl); | |
e3033736 | 477 | rcu_sync_torture_init(); |
b2896d2e PM |
478 | } |
479 | ||
480 | static void srcu_torture_cleanup(void) | |
481 | { | |
482 | synchronize_srcu(&srcu_ctl); | |
483 | cleanup_srcu_struct(&srcu_ctl); | |
484 | } | |
485 | ||
012d3ca8 | 486 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
487 | { |
488 | return srcu_read_lock(&srcu_ctl); | |
489 | } | |
490 | ||
491 | static void srcu_read_delay(struct rcu_random_state *rrsp) | |
492 | { | |
493 | long delay; | |
494 | const long uspertick = 1000000 / HZ; | |
495 | const long longdelay = 10; | |
496 | ||
497 | /* We want there to be long-running readers, but not all the time. */ | |
498 | ||
499 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); | |
500 | if (!delay) | |
501 | schedule_timeout_interruptible(longdelay); | |
502 | } | |
503 | ||
012d3ca8 | 504 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
505 | { |
506 | srcu_read_unlock(&srcu_ctl, idx); | |
507 | } | |
508 | ||
509 | static int srcu_torture_completed(void) | |
510 | { | |
511 | return srcu_batches_completed(&srcu_ctl); | |
512 | } | |
513 | ||
b772e1dd JT |
514 | static void srcu_torture_synchronize(void) |
515 | { | |
516 | synchronize_srcu(&srcu_ctl); | |
517 | } | |
518 | ||
b2896d2e PM |
519 | static int srcu_torture_stats(char *page) |
520 | { | |
521 | int cnt = 0; | |
522 | int cpu; | |
523 | int idx = srcu_ctl.completed & 0x1; | |
524 | ||
525 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", | |
526 | torture_type, TORTURE_FLAG, idx); | |
527 | for_each_possible_cpu(cpu) { | |
528 | cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu, | |
529 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], | |
530 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
531 | } | |
532 | cnt += sprintf(&page[cnt], "\n"); | |
533 | return cnt; | |
534 | } | |
535 | ||
536 | static struct rcu_torture_ops srcu_ops = { | |
0acc512c PM |
537 | .init = srcu_torture_init, |
538 | .cleanup = srcu_torture_cleanup, | |
539 | .readlock = srcu_torture_read_lock, | |
540 | .read_delay = srcu_read_delay, | |
541 | .readunlock = srcu_torture_read_unlock, | |
542 | .completed = srcu_torture_completed, | |
543 | .deferred_free = rcu_sync_torture_deferred_free, | |
544 | .sync = srcu_torture_synchronize, | |
545 | .cb_barrier = NULL, | |
546 | .stats = srcu_torture_stats, | |
547 | .name = "srcu" | |
b2896d2e PM |
548 | }; |
549 | ||
4b6c2cca JT |
550 | /* |
551 | * Definitions for sched torture testing. | |
552 | */ | |
553 | ||
554 | static int sched_torture_read_lock(void) | |
555 | { | |
556 | preempt_disable(); | |
557 | return 0; | |
558 | } | |
559 | ||
560 | static void sched_torture_read_unlock(int idx) | |
561 | { | |
562 | preempt_enable(); | |
563 | } | |
564 | ||
565 | static int sched_torture_completed(void) | |
566 | { | |
567 | return 0; | |
568 | } | |
569 | ||
2326974d PM |
570 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
571 | { | |
572 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
573 | } | |
574 | ||
4b6c2cca JT |
575 | static void sched_torture_synchronize(void) |
576 | { | |
577 | synchronize_sched(); | |
578 | } | |
579 | ||
580 | static struct rcu_torture_ops sched_ops = { | |
0acc512c PM |
581 | .init = rcu_sync_torture_init, |
582 | .cleanup = NULL, | |
583 | .readlock = sched_torture_read_lock, | |
584 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
585 | .readunlock = sched_torture_read_unlock, | |
586 | .completed = sched_torture_completed, | |
587 | .deferred_free = rcu_sched_torture_deferred_free, | |
588 | .sync = sched_torture_synchronize, | |
589 | .cb_barrier = rcu_barrier_sched, | |
590 | .stats = NULL, | |
591 | .irq_capable = 1, | |
592 | .name = "sched" | |
4b6c2cca JT |
593 | }; |
594 | ||
2326974d | 595 | static struct rcu_torture_ops sched_ops_sync = { |
0acc512c PM |
596 | .init = rcu_sync_torture_init, |
597 | .cleanup = NULL, | |
598 | .readlock = sched_torture_read_lock, | |
599 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
600 | .readunlock = sched_torture_read_unlock, | |
601 | .completed = sched_torture_completed, | |
602 | .deferred_free = rcu_sync_torture_deferred_free, | |
603 | .sync = sched_torture_synchronize, | |
604 | .cb_barrier = NULL, | |
605 | .stats = NULL, | |
606 | .name = "sched_sync" | |
607 | }; | |
608 | ||
609 | extern int rcu_expedited_torture_stats(char *page); | |
610 | ||
611 | static struct rcu_torture_ops sched_expedited_ops = { | |
612 | .init = rcu_sync_torture_init, | |
613 | .cleanup = NULL, | |
614 | .readlock = sched_torture_read_lock, | |
615 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
616 | .readunlock = sched_torture_read_unlock, | |
617 | .completed = sched_torture_completed, | |
618 | .deferred_free = rcu_sync_torture_deferred_free, | |
619 | .sync = synchronize_sched_expedited, | |
620 | .cb_barrier = NULL, | |
621 | .stats = rcu_expedited_torture_stats, | |
622 | .irq_capable = 1, | |
623 | .name = "sched_expedited" | |
2326974d PM |
624 | }; |
625 | ||
a241ec65 PM |
626 | /* |
627 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
628 | * for that pointed to by rcu_torture_current, freeing the old structure | |
629 | * after a series of grace periods (the "pipeline"). | |
630 | */ | |
631 | static int | |
632 | rcu_torture_writer(void *arg) | |
633 | { | |
634 | int i; | |
635 | long oldbatch = rcu_batches_completed(); | |
636 | struct rcu_torture *rp; | |
637 | struct rcu_torture *old_rp; | |
638 | static DEFINE_RCU_RANDOM(rand); | |
639 | ||
640 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
641 | set_user_nice(current, 19); |
642 | ||
a241ec65 PM |
643 | do { |
644 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
645 | rp = rcu_torture_alloc(); |
646 | if (rp == NULL) | |
a241ec65 PM |
647 | continue; |
648 | rp->rtort_pipe_count = 0; | |
649 | udelay(rcu_random(&rand) & 0x3ff); | |
650 | old_rp = rcu_torture_current; | |
996417d2 | 651 | rp->rtort_mbtest = 1; |
a241ec65 PM |
652 | rcu_assign_pointer(rcu_torture_current, rp); |
653 | smp_wmb(); | |
c8e5b163 | 654 | if (old_rp) { |
a241ec65 PM |
655 | i = old_rp->rtort_pipe_count; |
656 | if (i > RCU_TORTURE_PIPE_LEN) | |
657 | i = RCU_TORTURE_PIPE_LEN; | |
658 | atomic_inc(&rcu_torture_wcount[i]); | |
659 | old_rp->rtort_pipe_count++; | |
0acc512c | 660 | cur_ops->deferred_free(old_rp); |
a241ec65 PM |
661 | } |
662 | rcu_torture_current_version++; | |
72e9bb54 | 663 | oldbatch = cur_ops->completed(); |
c9d557c1 PM |
664 | rcu_stutter_wait("rcu_torture_writer"); |
665 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 666 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
667 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
668 | while (!kthread_should_stop()) | |
a241ec65 PM |
669 | schedule_timeout_uninterruptible(1); |
670 | return 0; | |
671 | } | |
672 | ||
b772e1dd JT |
673 | /* |
674 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
675 | * delay between calls. | |
676 | */ | |
677 | static int | |
678 | rcu_torture_fakewriter(void *arg) | |
679 | { | |
680 | DEFINE_RCU_RANDOM(rand); | |
681 | ||
682 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
683 | set_user_nice(current, 19); | |
684 | ||
685 | do { | |
686 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); | |
687 | udelay(rcu_random(&rand) & 0x3ff); | |
688 | cur_ops->sync(); | |
c9d557c1 PM |
689 | rcu_stutter_wait("rcu_torture_fakewriter"); |
690 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
691 | |
692 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
693 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
694 | while (!kthread_should_stop()) | |
b772e1dd JT |
695 | schedule_timeout_uninterruptible(1); |
696 | return 0; | |
697 | } | |
698 | ||
0729fbf3 PM |
699 | /* |
700 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
701 | * incrementing the corresponding element of the pipeline array. The | |
702 | * counter in the element should never be greater than 1, otherwise, the | |
703 | * RCU implementation is broken. | |
704 | */ | |
705 | static void rcu_torture_timer(unsigned long unused) | |
706 | { | |
707 | int idx; | |
708 | int completed; | |
709 | static DEFINE_RCU_RANDOM(rand); | |
710 | static DEFINE_SPINLOCK(rand_lock); | |
711 | struct rcu_torture *p; | |
712 | int pipe_count; | |
713 | ||
714 | idx = cur_ops->readlock(); | |
715 | completed = cur_ops->completed(); | |
716 | p = rcu_dereference(rcu_torture_current); | |
717 | if (p == NULL) { | |
718 | /* Leave because rcu_torture_writer is not yet underway */ | |
719 | cur_ops->readunlock(idx); | |
720 | return; | |
721 | } | |
722 | if (p->rtort_mbtest == 0) | |
723 | atomic_inc(&n_rcu_torture_mberror); | |
724 | spin_lock(&rand_lock); | |
0acc512c | 725 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
726 | n_rcu_torture_timers++; |
727 | spin_unlock(&rand_lock); | |
728 | preempt_disable(); | |
729 | pipe_count = p->rtort_pipe_count; | |
730 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
731 | /* Should not happen, but... */ | |
732 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
733 | } | |
dd17c8f7 | 734 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
0729fbf3 PM |
735 | completed = cur_ops->completed() - completed; |
736 | if (completed > RCU_TORTURE_PIPE_LEN) { | |
737 | /* Should not happen, but... */ | |
738 | completed = RCU_TORTURE_PIPE_LEN; | |
739 | } | |
dd17c8f7 | 740 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
741 | preempt_enable(); |
742 | cur_ops->readunlock(idx); | |
743 | } | |
744 | ||
a241ec65 PM |
745 | /* |
746 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
747 | * incrementing the corresponding element of the pipeline array. The | |
748 | * counter in the element should never be greater than 1, otherwise, the | |
749 | * RCU implementation is broken. | |
750 | */ | |
751 | static int | |
752 | rcu_torture_reader(void *arg) | |
753 | { | |
754 | int completed; | |
72e9bb54 | 755 | int idx; |
a241ec65 PM |
756 | DEFINE_RCU_RANDOM(rand); |
757 | struct rcu_torture *p; | |
758 | int pipe_count; | |
0729fbf3 | 759 | struct timer_list t; |
a241ec65 PM |
760 | |
761 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 762 | set_user_nice(current, 19); |
0acc512c | 763 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 764 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 765 | |
a241ec65 | 766 | do { |
0acc512c | 767 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 PM |
768 | if (!timer_pending(&t)) |
769 | mod_timer(&t, 1); | |
770 | } | |
72e9bb54 PM |
771 | idx = cur_ops->readlock(); |
772 | completed = cur_ops->completed(); | |
a241ec65 PM |
773 | p = rcu_dereference(rcu_torture_current); |
774 | if (p == NULL) { | |
775 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 776 | cur_ops->readunlock(idx); |
a241ec65 PM |
777 | schedule_timeout_interruptible(HZ); |
778 | continue; | |
779 | } | |
996417d2 PM |
780 | if (p->rtort_mbtest == 0) |
781 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 782 | cur_ops->read_delay(&rand); |
a241ec65 PM |
783 | preempt_disable(); |
784 | pipe_count = p->rtort_pipe_count; | |
785 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
786 | /* Should not happen, but... */ | |
787 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
788 | } | |
dd17c8f7 | 789 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
72e9bb54 | 790 | completed = cur_ops->completed() - completed; |
a241ec65 PM |
791 | if (completed > RCU_TORTURE_PIPE_LEN) { |
792 | /* Should not happen, but... */ | |
793 | completed = RCU_TORTURE_PIPE_LEN; | |
794 | } | |
dd17c8f7 | 795 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 796 | preempt_enable(); |
72e9bb54 | 797 | cur_ops->readunlock(idx); |
a241ec65 | 798 | schedule(); |
c9d557c1 PM |
799 | rcu_stutter_wait("rcu_torture_reader"); |
800 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 801 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 802 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0acc512c | 803 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 804 | del_timer_sync(&t); |
c9d557c1 | 805 | while (!kthread_should_stop()) |
a241ec65 PM |
806 | schedule_timeout_uninterruptible(1); |
807 | return 0; | |
808 | } | |
809 | ||
810 | /* | |
811 | * Create an RCU-torture statistics message in the specified buffer. | |
812 | */ | |
813 | static int | |
814 | rcu_torture_printk(char *page) | |
815 | { | |
816 | int cnt = 0; | |
817 | int cpu; | |
818 | int i; | |
819 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
820 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
821 | ||
0a945022 | 822 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
823 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
824 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
825 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
826 | } | |
827 | } | |
828 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
829 | if (pipesummary[i] != 0) | |
830 | break; | |
831 | } | |
72e9bb54 | 832 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 833 | cnt += sprintf(&page[cnt], |
996417d2 | 834 | "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d " |
0729fbf3 | 835 | "rtmbe: %d nt: %ld", |
a241ec65 PM |
836 | rcu_torture_current, |
837 | rcu_torture_current_version, | |
838 | list_empty(&rcu_torture_freelist), | |
839 | atomic_read(&n_rcu_torture_alloc), | |
840 | atomic_read(&n_rcu_torture_alloc_fail), | |
996417d2 | 841 | atomic_read(&n_rcu_torture_free), |
0729fbf3 PM |
842 | atomic_read(&n_rcu_torture_mberror), |
843 | n_rcu_torture_timers); | |
996417d2 PM |
844 | if (atomic_read(&n_rcu_torture_mberror) != 0) |
845 | cnt += sprintf(&page[cnt], " !!!"); | |
72e9bb54 | 846 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
996417d2 | 847 | if (i > 1) { |
a241ec65 | 848 | cnt += sprintf(&page[cnt], "!!! "); |
996417d2 | 849 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 850 | WARN_ON_ONCE(1); |
996417d2 | 851 | } |
a241ec65 PM |
852 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
853 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) | |
854 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); | |
72e9bb54 | 855 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 856 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
72e9bb54 | 857 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
a241ec65 | 858 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
72e9bb54 | 859 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 PM |
860 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
861 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { | |
862 | cnt += sprintf(&page[cnt], " %d", | |
863 | atomic_read(&rcu_torture_wcount[i])); | |
864 | } | |
865 | cnt += sprintf(&page[cnt], "\n"); | |
c8e5b163 | 866 | if (cur_ops->stats) |
72e9bb54 | 867 | cnt += cur_ops->stats(&page[cnt]); |
a241ec65 PM |
868 | return cnt; |
869 | } | |
870 | ||
871 | /* | |
872 | * Print torture statistics. Caller must ensure that there is only | |
873 | * one call to this function at a given time!!! This is normally | |
874 | * accomplished by relying on the module system to only have one copy | |
875 | * of the module loaded, and then by giving the rcu_torture_stats | |
876 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
877 | * thread is not running). | |
878 | */ | |
879 | static void | |
880 | rcu_torture_stats_print(void) | |
881 | { | |
882 | int cnt; | |
883 | ||
884 | cnt = rcu_torture_printk(printk_buf); | |
885 | printk(KERN_ALERT "%s", printk_buf); | |
886 | } | |
887 | ||
888 | /* | |
889 | * Periodically prints torture statistics, if periodic statistics printing | |
890 | * was specified via the stat_interval module parameter. | |
891 | * | |
892 | * No need to worry about fullstop here, since this one doesn't reference | |
893 | * volatile state or register callbacks. | |
894 | */ | |
895 | static int | |
896 | rcu_torture_stats(void *arg) | |
897 | { | |
898 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
899 | do { | |
900 | schedule_timeout_interruptible(stat_interval * HZ); | |
901 | rcu_torture_stats_print(); | |
c9d557c1 PM |
902 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
903 | } while (!kthread_should_stop()); | |
a241ec65 PM |
904 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
905 | return 0; | |
906 | } | |
907 | ||
d84f5203 SV |
908 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
909 | ||
910 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
911 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
912 | */ | |
b2896d2e | 913 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 914 | { |
d84f5203 SV |
915 | int i; |
916 | ||
73d0a4b1 | 917 | cpumask_setall(shuffle_tmp_mask); |
86ef5c9a | 918 | get_online_cpus(); |
d84f5203 SV |
919 | |
920 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
921 | if (num_online_cpus() == 1) { |
922 | put_online_cpus(); | |
923 | return; | |
924 | } | |
d84f5203 SV |
925 | |
926 | if (rcu_idle_cpu != -1) | |
73d0a4b1 | 927 | cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); |
d84f5203 | 928 | |
73d0a4b1 | 929 | set_cpus_allowed_ptr(current, shuffle_tmp_mask); |
d84f5203 | 930 | |
c8e5b163 | 931 | if (reader_tasks) { |
d84f5203 SV |
932 | for (i = 0; i < nrealreaders; i++) |
933 | if (reader_tasks[i]) | |
f70316da | 934 | set_cpus_allowed_ptr(reader_tasks[i], |
73d0a4b1 | 935 | shuffle_tmp_mask); |
d84f5203 SV |
936 | } |
937 | ||
c8e5b163 | 938 | if (fakewriter_tasks) { |
b772e1dd JT |
939 | for (i = 0; i < nfakewriters; i++) |
940 | if (fakewriter_tasks[i]) | |
f70316da | 941 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
73d0a4b1 | 942 | shuffle_tmp_mask); |
b772e1dd JT |
943 | } |
944 | ||
d84f5203 | 945 | if (writer_task) |
73d0a4b1 | 946 | set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); |
d84f5203 SV |
947 | |
948 | if (stats_task) | |
73d0a4b1 | 949 | set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); |
d84f5203 SV |
950 | |
951 | if (rcu_idle_cpu == -1) | |
952 | rcu_idle_cpu = num_online_cpus() - 1; | |
953 | else | |
954 | rcu_idle_cpu--; | |
955 | ||
86ef5c9a | 956 | put_online_cpus(); |
d84f5203 SV |
957 | } |
958 | ||
959 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
960 | * system to become idle at a time and cut off its timer ticks. This is meant | |
961 | * to test the support for such tickless idle CPU in RCU. | |
962 | */ | |
963 | static int | |
964 | rcu_torture_shuffle(void *arg) | |
965 | { | |
966 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
967 | do { | |
968 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
969 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
970 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
971 | } while (!kthread_should_stop()); | |
d84f5203 SV |
972 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
973 | return 0; | |
974 | } | |
975 | ||
d120f65f PM |
976 | /* Cause the rcutorture test to "stutter", starting and stopping all |
977 | * threads periodically. | |
978 | */ | |
979 | static int | |
980 | rcu_torture_stutter(void *arg) | |
981 | { | |
982 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
983 | do { | |
984 | schedule_timeout_interruptible(stutter * HZ); | |
985 | stutter_pause_test = 1; | |
c9d557c1 | 986 | if (!kthread_should_stop()) |
d120f65f PM |
987 | schedule_timeout_interruptible(stutter * HZ); |
988 | stutter_pause_test = 0; | |
c9d557c1 PM |
989 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
990 | } while (!kthread_should_stop()); | |
d120f65f PM |
991 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
992 | return 0; | |
993 | } | |
994 | ||
95c38322 PM |
995 | static inline void |
996 | rcu_torture_print_module_parms(char *tag) | |
997 | { | |
b772e1dd JT |
998 | printk(KERN_ALERT "%s" TORTURE_FLAG |
999 | "--- %s: nreaders=%d nfakewriters=%d " | |
95c38322 | 1000 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
0729fbf3 | 1001 | "shuffle_interval=%d stutter=%d irqreader=%d\n", |
b772e1dd | 1002 | torture_type, tag, nrealreaders, nfakewriters, |
d120f65f | 1003 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, |
0729fbf3 | 1004 | stutter, irqreader); |
95c38322 PM |
1005 | } |
1006 | ||
343e9099 PM |
1007 | static struct notifier_block rcutorture_nb = { |
1008 | .notifier_call = rcutorture_shutdown_notify, | |
1009 | }; | |
1010 | ||
a241ec65 PM |
1011 | static void |
1012 | rcu_torture_cleanup(void) | |
1013 | { | |
1014 | int i; | |
1015 | ||
343e9099 | 1016 | mutex_lock(&fullstop_mutex); |
c9d557c1 PM |
1017 | if (fullstop == FULLSTOP_SHUTDOWN) { |
1018 | printk(KERN_WARNING /* but going down anyway, so... */ | |
1019 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
343e9099 | 1020 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 1021 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1022 | if (cur_ops->cb_barrier != NULL) |
1023 | cur_ops->cb_barrier(); | |
1024 | return; | |
1025 | } | |
c9d557c1 | 1026 | fullstop = FULLSTOP_RMMOD; |
343e9099 PM |
1027 | mutex_unlock(&fullstop_mutex); |
1028 | unregister_reboot_notifier(&rcutorture_nb); | |
d120f65f PM |
1029 | if (stutter_task) { |
1030 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1031 | kthread_stop(stutter_task); | |
1032 | } | |
1033 | stutter_task = NULL; | |
c8e5b163 | 1034 | if (shuffler_task) { |
d84f5203 SV |
1035 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1036 | kthread_stop(shuffler_task); | |
73d0a4b1 | 1037 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1038 | } |
1039 | shuffler_task = NULL; | |
1040 | ||
c8e5b163 | 1041 | if (writer_task) { |
a241ec65 PM |
1042 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1043 | kthread_stop(writer_task); | |
1044 | } | |
1045 | writer_task = NULL; | |
1046 | ||
c8e5b163 | 1047 | if (reader_tasks) { |
a241ec65 | 1048 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1049 | if (reader_tasks[i]) { |
a241ec65 PM |
1050 | VERBOSE_PRINTK_STRING( |
1051 | "Stopping rcu_torture_reader task"); | |
1052 | kthread_stop(reader_tasks[i]); | |
1053 | } | |
1054 | reader_tasks[i] = NULL; | |
1055 | } | |
1056 | kfree(reader_tasks); | |
1057 | reader_tasks = NULL; | |
1058 | } | |
1059 | rcu_torture_current = NULL; | |
1060 | ||
c8e5b163 | 1061 | if (fakewriter_tasks) { |
b772e1dd | 1062 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1063 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1064 | VERBOSE_PRINTK_STRING( |
1065 | "Stopping rcu_torture_fakewriter task"); | |
1066 | kthread_stop(fakewriter_tasks[i]); | |
1067 | } | |
1068 | fakewriter_tasks[i] = NULL; | |
1069 | } | |
1070 | kfree(fakewriter_tasks); | |
1071 | fakewriter_tasks = NULL; | |
1072 | } | |
1073 | ||
c8e5b163 | 1074 | if (stats_task) { |
a241ec65 PM |
1075 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1076 | kthread_stop(stats_task); | |
1077 | } | |
1078 | stats_task = NULL; | |
1079 | ||
1080 | /* Wait for all RCU callbacks to fire. */ | |
2326974d PM |
1081 | |
1082 | if (cur_ops->cb_barrier != NULL) | |
1083 | cur_ops->cb_barrier(); | |
a241ec65 | 1084 | |
a241ec65 | 1085 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1086 | |
c8e5b163 | 1087 | if (cur_ops->cleanup) |
72e9bb54 | 1088 | cur_ops->cleanup(); |
95c38322 PM |
1089 | if (atomic_read(&n_rcu_torture_error)) |
1090 | rcu_torture_print_module_parms("End of test: FAILURE"); | |
1091 | else | |
1092 | rcu_torture_print_module_parms("End of test: SUCCESS"); | |
a241ec65 PM |
1093 | } |
1094 | ||
6f8bc500 | 1095 | static int __init |
a241ec65 PM |
1096 | rcu_torture_init(void) |
1097 | { | |
1098 | int i; | |
1099 | int cpu; | |
1100 | int firsterr = 0; | |
ade5fb81 JT |
1101 | static struct rcu_torture_ops *torture_ops[] = |
1102 | { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops, | |
0acc512c | 1103 | &sched_expedited_ops, |
2326974d | 1104 | &srcu_ops, &sched_ops, &sched_ops_sync, }; |
a241ec65 | 1105 | |
343e9099 PM |
1106 | mutex_lock(&fullstop_mutex); |
1107 | ||
a241ec65 | 1108 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1109 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1110 | cur_ops = torture_ops[i]; |
ade5fb81 | 1111 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1112 | break; |
72e9bb54 | 1113 | } |
ade5fb81 | 1114 | if (i == ARRAY_SIZE(torture_ops)) { |
72e9bb54 PM |
1115 | printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n", |
1116 | torture_type); | |
343e9099 | 1117 | mutex_unlock(&fullstop_mutex); |
a71fca58 | 1118 | return -EINVAL; |
72e9bb54 | 1119 | } |
c8e5b163 | 1120 | if (cur_ops->init) |
72e9bb54 PM |
1121 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1122 | ||
a241ec65 PM |
1123 | if (nreaders >= 0) |
1124 | nrealreaders = nreaders; | |
1125 | else | |
1126 | nrealreaders = 2 * num_online_cpus(); | |
95c38322 | 1127 | rcu_torture_print_module_parms("Start of test"); |
c9d557c1 | 1128 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1129 | |
1130 | /* Set up the freelist. */ | |
1131 | ||
1132 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1133 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1134 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1135 | list_add_tail(&rcu_tortures[i].rtort_free, |
1136 | &rcu_torture_freelist); | |
1137 | } | |
1138 | ||
1139 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1140 | ||
1141 | rcu_torture_current = NULL; | |
1142 | rcu_torture_current_version = 0; | |
1143 | atomic_set(&n_rcu_torture_alloc, 0); | |
1144 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1145 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1146 | atomic_set(&n_rcu_torture_mberror, 0); |
1147 | atomic_set(&n_rcu_torture_error, 0); | |
a241ec65 PM |
1148 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1149 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1150 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1151 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1152 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1153 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1154 | } | |
1155 | } | |
1156 | ||
1157 | /* Start up the kthreads. */ | |
1158 | ||
1159 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
1160 | writer_task = kthread_run(rcu_torture_writer, NULL, | |
1161 | "rcu_torture_writer"); | |
1162 | if (IS_ERR(writer_task)) { | |
1163 | firsterr = PTR_ERR(writer_task); | |
1164 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
1165 | writer_task = NULL; | |
1166 | goto unwind; | |
1167 | } | |
b772e1dd | 1168 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1169 | GFP_KERNEL); |
b772e1dd JT |
1170 | if (fakewriter_tasks == NULL) { |
1171 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1172 | firsterr = -ENOMEM; | |
1173 | goto unwind; | |
1174 | } | |
1175 | for (i = 0; i < nfakewriters; i++) { | |
1176 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
1177 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
a71fca58 | 1178 | "rcu_torture_fakewriter"); |
b772e1dd JT |
1179 | if (IS_ERR(fakewriter_tasks[i])) { |
1180 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
1181 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
1182 | fakewriter_tasks[i] = NULL; | |
1183 | goto unwind; | |
1184 | } | |
1185 | } | |
2860aaba | 1186 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1187 | GFP_KERNEL); |
1188 | if (reader_tasks == NULL) { | |
1189 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1190 | firsterr = -ENOMEM; | |
1191 | goto unwind; | |
1192 | } | |
1193 | for (i = 0; i < nrealreaders; i++) { | |
1194 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
1195 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
1196 | "rcu_torture_reader"); | |
1197 | if (IS_ERR(reader_tasks[i])) { | |
1198 | firsterr = PTR_ERR(reader_tasks[i]); | |
1199 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
1200 | reader_tasks[i] = NULL; | |
1201 | goto unwind; | |
1202 | } | |
1203 | } | |
1204 | if (stat_interval > 0) { | |
1205 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
1206 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
1207 | "rcu_torture_stats"); | |
1208 | if (IS_ERR(stats_task)) { | |
1209 | firsterr = PTR_ERR(stats_task); | |
1210 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
1211 | stats_task = NULL; | |
1212 | goto unwind; | |
1213 | } | |
1214 | } | |
d84f5203 SV |
1215 | if (test_no_idle_hz) { |
1216 | rcu_idle_cpu = num_online_cpus() - 1; | |
73d0a4b1 RR |
1217 | |
1218 | if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { | |
1219 | firsterr = -ENOMEM; | |
1220 | VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); | |
1221 | goto unwind; | |
1222 | } | |
1223 | ||
d84f5203 SV |
1224 | /* Create the shuffler thread */ |
1225 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
1226 | "rcu_torture_shuffle"); | |
1227 | if (IS_ERR(shuffler_task)) { | |
73d0a4b1 | 1228 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1229 | firsterr = PTR_ERR(shuffler_task); |
1230 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
1231 | shuffler_task = NULL; | |
1232 | goto unwind; | |
1233 | } | |
1234 | } | |
d120f65f PM |
1235 | if (stutter < 0) |
1236 | stutter = 0; | |
1237 | if (stutter) { | |
1238 | /* Create the stutter thread */ | |
1239 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
1240 | "rcu_torture_stutter"); | |
1241 | if (IS_ERR(stutter_task)) { | |
1242 | firsterr = PTR_ERR(stutter_task); | |
1243 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
1244 | stutter_task = NULL; | |
1245 | goto unwind; | |
1246 | } | |
1247 | } | |
343e9099 PM |
1248 | register_reboot_notifier(&rcutorture_nb); |
1249 | mutex_unlock(&fullstop_mutex); | |
a241ec65 PM |
1250 | return 0; |
1251 | ||
1252 | unwind: | |
343e9099 | 1253 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1254 | rcu_torture_cleanup(); |
1255 | return firsterr; | |
1256 | } | |
1257 | ||
1258 | module_init(rcu_torture_init); | |
1259 | module_exit(rcu_torture_cleanup); |