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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 | |
87de1cfd PM |
15 | * along with this program; if not, you can access it online at |
16 | * http://www.gnu.org/licenses/gpl-2.0.html. | |
a241ec65 | 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> | |
60063497 | 36 | #include <linux/atomic.h> |
a241ec65 | 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> |
52494535 | 49 | #include <linux/trace_clock.h> |
f07767fd | 50 | #include <asm/byteorder.h> |
51b1130e | 51 | #include <linux/torture.h> |
a241ec65 PM |
52 | |
53 | MODULE_LICENSE("GPL"); | |
5cf05ad7 | 54 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>"); |
a241ec65 | 55 | |
4102adab | 56 | |
9e250225 PM |
57 | torture_param(int, fqs_duration, 0, |
58 | "Duration of fqs bursts (us), 0 to disable"); | |
59 | torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)"); | |
60 | torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)"); | |
61 | torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); | |
62 | torture_param(bool, gp_normal, false, | |
63 | "Use normal (non-expedited) GP wait primitives"); | |
64 | torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers"); | |
65 | torture_param(int, n_barrier_cbs, 0, | |
66 | "# of callbacks/kthreads for barrier testing"); | |
67 | torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads"); | |
68 | torture_param(int, nreaders, -1, "Number of RCU reader threads"); | |
69 | torture_param(int, object_debug, 0, | |
70 | "Enable debug-object double call_rcu() testing"); | |
71 | torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); | |
72 | torture_param(int, onoff_interval, 0, | |
73 | "Time between CPU hotplugs (s), 0=disable"); | |
74 | torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); | |
75 | torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); | |
76 | torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); | |
77 | torture_param(int, stall_cpu_holdoff, 10, | |
78 | "Time to wait before starting stall (s)."); | |
79 | torture_param(int, stat_interval, 60, | |
80 | "Number of seconds between stats printk()s"); | |
81 | torture_param(int, stutter, 5, "Number of seconds to run/halt test"); | |
82 | torture_param(int, test_boost, 1, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); | |
83 | torture_param(int, test_boost_duration, 4, | |
84 | "Duration of each boost test, seconds."); | |
85 | torture_param(int, test_boost_interval, 7, | |
86 | "Interval between boost tests, seconds."); | |
87 | torture_param(bool, test_no_idle_hz, true, | |
88 | "Test support for tickless idle CPUs"); | |
b5daa8f3 PM |
89 | torture_param(bool, verbose, true, |
90 | "Enable verbose debugging printk()s"); | |
9e250225 | 91 | |
d10453e9 | 92 | static char *torture_type = "rcu"; |
d6ad6711 | 93 | module_param(torture_type, charp, 0444); |
d10453e9 | 94 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, ...)"); |
a241ec65 | 95 | |
a241ec65 PM |
96 | static int nrealreaders; |
97 | static struct task_struct *writer_task; | |
b772e1dd | 98 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
99 | static struct task_struct **reader_tasks; |
100 | static struct task_struct *stats_task; | |
bf66f18e | 101 | static struct task_struct *fqs_task; |
8e8be45e | 102 | static struct task_struct *boost_tasks[NR_CPUS]; |
c13f3757 | 103 | static struct task_struct *stall_task; |
fae4b54f PM |
104 | static struct task_struct **barrier_cbs_tasks; |
105 | static struct task_struct *barrier_task; | |
a241ec65 PM |
106 | |
107 | #define RCU_TORTURE_PIPE_LEN 10 | |
108 | ||
109 | struct rcu_torture { | |
110 | struct rcu_head rtort_rcu; | |
111 | int rtort_pipe_count; | |
112 | struct list_head rtort_free; | |
996417d2 | 113 | int rtort_mbtest; |
a241ec65 PM |
114 | }; |
115 | ||
a241ec65 | 116 | static LIST_HEAD(rcu_torture_freelist); |
0ddea0ea | 117 | static struct rcu_torture __rcu *rcu_torture_current; |
4a298656 | 118 | static unsigned long rcu_torture_current_version; |
a241ec65 PM |
119 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
120 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
806274c0 PM |
121 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], |
122 | rcu_torture_count) = { 0 }; | |
123 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], | |
124 | rcu_torture_batch) = { 0 }; | |
a241ec65 | 125 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; |
b2896d2e PM |
126 | static atomic_t n_rcu_torture_alloc; |
127 | static atomic_t n_rcu_torture_alloc_fail; | |
128 | static atomic_t n_rcu_torture_free; | |
129 | static atomic_t n_rcu_torture_mberror; | |
130 | static atomic_t n_rcu_torture_error; | |
fae4b54f | 131 | static long n_rcu_torture_barrier_error; |
8e8be45e PM |
132 | static long n_rcu_torture_boost_ktrerror; |
133 | static long n_rcu_torture_boost_rterror; | |
8e8be45e PM |
134 | static long n_rcu_torture_boost_failure; |
135 | static long n_rcu_torture_boosts; | |
a71fca58 | 136 | static long n_rcu_torture_timers; |
fae4b54f PM |
137 | static long n_barrier_attempts; |
138 | static long n_barrier_successes; | |
e3033736 | 139 | static struct list_head rcu_torture_removed; |
d120f65f | 140 | |
31a72bce PM |
141 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
142 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
143 | #else | |
144 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
145 | #endif | |
146 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
bb3bf705 PM |
147 | module_param(rcutorture_runnable, int, 0444); |
148 | MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot"); | |
31a72bce | 149 | |
3acf4a9a | 150 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 151 | #define rcu_can_boost() 1 |
3acf4a9a | 152 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 153 | #define rcu_can_boost() 0 |
3acf4a9a | 154 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 155 | |
e4aa0da3 SR |
156 | #ifdef CONFIG_RCU_TRACE |
157 | static u64 notrace rcu_trace_clock_local(void) | |
158 | { | |
159 | u64 ts = trace_clock_local(); | |
160 | unsigned long __maybe_unused ts_rem = do_div(ts, NSEC_PER_USEC); | |
161 | return ts; | |
162 | } | |
163 | #else /* #ifdef CONFIG_RCU_TRACE */ | |
164 | static u64 notrace rcu_trace_clock_local(void) | |
165 | { | |
166 | return 0ULL; | |
167 | } | |
168 | #endif /* #else #ifdef CONFIG_RCU_TRACE */ | |
169 | ||
8e8be45e PM |
170 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
171 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
172 | /* and boost task create/destroy. */ | |
fae4b54f | 173 | static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */ |
c6ebcbb6 | 174 | static bool barrier_phase; /* Test phase. */ |
fae4b54f PM |
175 | static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */ |
176 | static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */ | |
177 | static DECLARE_WAIT_QUEUE_HEAD(barrier_wq); | |
8e8be45e | 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 | ||
72e9bb54 PM |
212 | /* |
213 | * Operations vector for selecting different types of tests. | |
214 | */ | |
215 | ||
216 | struct rcu_torture_ops { | |
217 | void (*init)(void); | |
72e9bb54 | 218 | int (*readlock)(void); |
51b1130e | 219 | void (*read_delay)(struct torture_random_state *rrsp); |
72e9bb54 PM |
220 | void (*readunlock)(int idx); |
221 | int (*completed)(void); | |
0acc512c | 222 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 223 | void (*sync)(void); |
2ec1f2d9 | 224 | void (*exp_sync)(void); |
fae4b54f | 225 | void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); |
2326974d | 226 | void (*cb_barrier)(void); |
bf66f18e | 227 | void (*fqs)(void); |
d1008950 | 228 | void (*stats)(char *page); |
0acc512c | 229 | int irq_capable; |
8e8be45e | 230 | int can_boost; |
e66c33d5 | 231 | const char *name; |
72e9bb54 | 232 | }; |
a71fca58 PM |
233 | |
234 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
235 | |
236 | /* | |
237 | * Definitions for rcu torture testing. | |
238 | */ | |
239 | ||
a49a4af7 | 240 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
241 | { |
242 | rcu_read_lock(); | |
243 | return 0; | |
244 | } | |
245 | ||
51b1130e | 246 | static void rcu_read_delay(struct torture_random_state *rrsp) |
b2896d2e | 247 | { |
b8d57a76 JT |
248 | const unsigned long shortdelay_us = 200; |
249 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 250 | |
b8d57a76 JT |
251 | /* We want a short delay sometimes to make a reader delay the grace |
252 | * period, and we want a long delay occasionally to trigger | |
253 | * force_quiescent_state. */ | |
b2896d2e | 254 | |
51b1130e | 255 | if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
b8d57a76 | 256 | mdelay(longdelay_ms); |
51b1130e | 257 | if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) |
b8d57a76 | 258 | udelay(shortdelay_us); |
e546f485 | 259 | #ifdef CONFIG_PREEMPT |
51b1130e PM |
260 | if (!preempt_count() && |
261 | !(torture_random(rrsp) % (nrealreaders * 20000))) | |
e546f485 LJ |
262 | preempt_schedule(); /* No QS if preempt_disable() in effect */ |
263 | #endif | |
b2896d2e PM |
264 | } |
265 | ||
a49a4af7 | 266 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
267 | { |
268 | rcu_read_unlock(); | |
269 | } | |
270 | ||
271 | static int rcu_torture_completed(void) | |
272 | { | |
273 | return rcu_batches_completed(); | |
274 | } | |
275 | ||
276 | static void | |
277 | rcu_torture_cb(struct rcu_head *p) | |
278 | { | |
279 | int i; | |
280 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
281 | ||
36970bb9 | 282 | if (torture_must_stop_irq()) { |
72e9bb54 PM |
283 | /* Test is ending, just drop callbacks on the floor. */ |
284 | /* The next initialization will pick up the pieces. */ | |
285 | return; | |
286 | } | |
287 | i = rp->rtort_pipe_count; | |
288 | if (i > RCU_TORTURE_PIPE_LEN) | |
289 | i = RCU_TORTURE_PIPE_LEN; | |
290 | atomic_inc(&rcu_torture_wcount[i]); | |
291 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
292 | rp->rtort_mbtest = 0; | |
293 | rcu_torture_free(rp); | |
c701d5d9 | 294 | } else { |
0acc512c | 295 | cur_ops->deferred_free(rp); |
c701d5d9 | 296 | } |
72e9bb54 PM |
297 | } |
298 | ||
d9a3da06 PM |
299 | static int rcu_no_completed(void) |
300 | { | |
301 | return 0; | |
302 | } | |
303 | ||
72e9bb54 PM |
304 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
305 | { | |
306 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
307 | } | |
308 | ||
e3033736 JT |
309 | static void rcu_sync_torture_init(void) |
310 | { | |
311 | INIT_LIST_HEAD(&rcu_torture_removed); | |
312 | } | |
313 | ||
2ec1f2d9 | 314 | static struct rcu_torture_ops rcu_ops = { |
0acc512c | 315 | .init = rcu_sync_torture_init, |
0acc512c PM |
316 | .readlock = rcu_torture_read_lock, |
317 | .read_delay = rcu_read_delay, | |
318 | .readunlock = rcu_torture_read_unlock, | |
319 | .completed = rcu_torture_completed, | |
2ec1f2d9 | 320 | .deferred_free = rcu_torture_deferred_free, |
0acc512c | 321 | .sync = synchronize_rcu, |
2ec1f2d9 PM |
322 | .exp_sync = synchronize_rcu_expedited, |
323 | .call = call_rcu, | |
324 | .cb_barrier = rcu_barrier, | |
bf66f18e | 325 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
326 | .stats = NULL, |
327 | .irq_capable = 1, | |
8e8be45e | 328 | .can_boost = rcu_can_boost(), |
2ec1f2d9 | 329 | .name = "rcu" |
d9a3da06 PM |
330 | }; |
331 | ||
c32e0660 PM |
332 | /* |
333 | * Definitions for rcu_bh torture testing. | |
334 | */ | |
335 | ||
a49a4af7 | 336 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
337 | { |
338 | rcu_read_lock_bh(); | |
339 | return 0; | |
340 | } | |
341 | ||
a49a4af7 | 342 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
343 | { |
344 | rcu_read_unlock_bh(); | |
345 | } | |
346 | ||
347 | static int rcu_bh_torture_completed(void) | |
348 | { | |
349 | return rcu_batches_completed_bh(); | |
350 | } | |
351 | ||
352 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
353 | { | |
354 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
355 | } | |
356 | ||
357 | static struct rcu_torture_ops rcu_bh_ops = { | |
2ec1f2d9 | 358 | .init = rcu_sync_torture_init, |
0acc512c PM |
359 | .readlock = rcu_bh_torture_read_lock, |
360 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
361 | .readunlock = rcu_bh_torture_read_unlock, | |
362 | .completed = rcu_bh_torture_completed, | |
363 | .deferred_free = rcu_bh_torture_deferred_free, | |
bdf2a436 | 364 | .sync = synchronize_rcu_bh, |
2ec1f2d9 | 365 | .exp_sync = synchronize_rcu_bh_expedited, |
fae4b54f | 366 | .call = call_rcu_bh, |
0acc512c | 367 | .cb_barrier = rcu_barrier_bh, |
bf66f18e | 368 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
369 | .stats = NULL, |
370 | .irq_capable = 1, | |
371 | .name = "rcu_bh" | |
c32e0660 PM |
372 | }; |
373 | ||
ff20e251 PM |
374 | /* |
375 | * Don't even think about trying any of these in real life!!! | |
376 | * The names includes "busted", and they really means it! | |
377 | * The only purpose of these functions is to provide a buggy RCU | |
378 | * implementation to make sure that rcutorture correctly emits | |
379 | * buggy-RCU error messages. | |
380 | */ | |
381 | static void rcu_busted_torture_deferred_free(struct rcu_torture *p) | |
382 | { | |
383 | /* This is a deliberate bug for testing purposes only! */ | |
384 | rcu_torture_cb(&p->rtort_rcu); | |
385 | } | |
386 | ||
387 | static void synchronize_rcu_busted(void) | |
388 | { | |
389 | /* This is a deliberate bug for testing purposes only! */ | |
390 | } | |
391 | ||
392 | static void | |
393 | call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) | |
394 | { | |
395 | /* This is a deliberate bug for testing purposes only! */ | |
396 | func(head); | |
397 | } | |
398 | ||
399 | static struct rcu_torture_ops rcu_busted_ops = { | |
400 | .init = rcu_sync_torture_init, | |
401 | .readlock = rcu_torture_read_lock, | |
402 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
403 | .readunlock = rcu_torture_read_unlock, | |
404 | .completed = rcu_no_completed, | |
405 | .deferred_free = rcu_busted_torture_deferred_free, | |
406 | .sync = synchronize_rcu_busted, | |
407 | .exp_sync = synchronize_rcu_busted, | |
408 | .call = call_rcu_busted, | |
409 | .cb_barrier = NULL, | |
410 | .fqs = NULL, | |
411 | .stats = NULL, | |
412 | .irq_capable = 1, | |
413 | .name = "rcu_busted" | |
414 | }; | |
415 | ||
b2896d2e PM |
416 | /* |
417 | * Definitions for srcu torture testing. | |
418 | */ | |
419 | ||
cda4dc81 | 420 | DEFINE_STATIC_SRCU(srcu_ctl); |
b2896d2e | 421 | |
012d3ca8 | 422 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
423 | { |
424 | return srcu_read_lock(&srcu_ctl); | |
425 | } | |
426 | ||
51b1130e | 427 | static void srcu_read_delay(struct torture_random_state *rrsp) |
b2896d2e PM |
428 | { |
429 | long delay; | |
430 | const long uspertick = 1000000 / HZ; | |
431 | const long longdelay = 10; | |
432 | ||
433 | /* We want there to be long-running readers, but not all the time. */ | |
434 | ||
51b1130e PM |
435 | delay = torture_random(rrsp) % |
436 | (nrealreaders * 2 * longdelay * uspertick); | |
b2896d2e PM |
437 | if (!delay) |
438 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
439 | else |
440 | rcu_read_delay(rrsp); | |
b2896d2e PM |
441 | } |
442 | ||
012d3ca8 | 443 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
444 | { |
445 | srcu_read_unlock(&srcu_ctl, idx); | |
446 | } | |
447 | ||
448 | static int srcu_torture_completed(void) | |
449 | { | |
450 | return srcu_batches_completed(&srcu_ctl); | |
451 | } | |
452 | ||
9059c940 LJ |
453 | static void srcu_torture_deferred_free(struct rcu_torture *rp) |
454 | { | |
455 | call_srcu(&srcu_ctl, &rp->rtort_rcu, rcu_torture_cb); | |
456 | } | |
457 | ||
b772e1dd JT |
458 | static void srcu_torture_synchronize(void) |
459 | { | |
460 | synchronize_srcu(&srcu_ctl); | |
461 | } | |
462 | ||
e3f8d378 PM |
463 | static void srcu_torture_call(struct rcu_head *head, |
464 | void (*func)(struct rcu_head *head)) | |
465 | { | |
466 | call_srcu(&srcu_ctl, head, func); | |
467 | } | |
468 | ||
469 | static void srcu_torture_barrier(void) | |
470 | { | |
471 | srcu_barrier(&srcu_ctl); | |
472 | } | |
473 | ||
d1008950 | 474 | static void srcu_torture_stats(char *page) |
b2896d2e | 475 | { |
b2896d2e PM |
476 | int cpu; |
477 | int idx = srcu_ctl.completed & 0x1; | |
478 | ||
d1008950 | 479 | page += sprintf(page, "%s%s per-CPU(idx=%d):", |
b2896d2e PM |
480 | torture_type, TORTURE_FLAG, idx); |
481 | for_each_possible_cpu(cpu) { | |
d1008950 | 482 | page += sprintf(page, " %d(%lu,%lu)", cpu, |
b2896d2e PM |
483 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], |
484 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
485 | } | |
d1008950 | 486 | sprintf(page, "\n"); |
b2896d2e PM |
487 | } |
488 | ||
2ec1f2d9 PM |
489 | static void srcu_torture_synchronize_expedited(void) |
490 | { | |
491 | synchronize_srcu_expedited(&srcu_ctl); | |
492 | } | |
493 | ||
b2896d2e | 494 | static struct rcu_torture_ops srcu_ops = { |
cda4dc81 | 495 | .init = rcu_sync_torture_init, |
0acc512c PM |
496 | .readlock = srcu_torture_read_lock, |
497 | .read_delay = srcu_read_delay, | |
498 | .readunlock = srcu_torture_read_unlock, | |
499 | .completed = srcu_torture_completed, | |
9059c940 | 500 | .deferred_free = srcu_torture_deferred_free, |
0acc512c | 501 | .sync = srcu_torture_synchronize, |
2ec1f2d9 | 502 | .exp_sync = srcu_torture_synchronize_expedited, |
e3f8d378 PM |
503 | .call = srcu_torture_call, |
504 | .cb_barrier = srcu_torture_barrier, | |
0acc512c PM |
505 | .stats = srcu_torture_stats, |
506 | .name = "srcu" | |
b2896d2e PM |
507 | }; |
508 | ||
4b6c2cca JT |
509 | /* |
510 | * Definitions for sched torture testing. | |
511 | */ | |
512 | ||
513 | static int sched_torture_read_lock(void) | |
514 | { | |
515 | preempt_disable(); | |
516 | return 0; | |
517 | } | |
518 | ||
519 | static void sched_torture_read_unlock(int idx) | |
520 | { | |
521 | preempt_enable(); | |
522 | } | |
523 | ||
2326974d PM |
524 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
525 | { | |
526 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
527 | } | |
528 | ||
4b6c2cca | 529 | static struct rcu_torture_ops sched_ops = { |
0acc512c | 530 | .init = rcu_sync_torture_init, |
0acc512c PM |
531 | .readlock = sched_torture_read_lock, |
532 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
533 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 534 | .completed = rcu_no_completed, |
0acc512c | 535 | .deferred_free = rcu_sched_torture_deferred_free, |
bdf2a436 | 536 | .sync = synchronize_sched, |
2ec1f2d9 PM |
537 | .exp_sync = synchronize_sched_expedited, |
538 | .call = call_rcu_sched, | |
0acc512c | 539 | .cb_barrier = rcu_barrier_sched, |
bf66f18e | 540 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
541 | .stats = NULL, |
542 | .irq_capable = 1, | |
543 | .name = "sched" | |
4b6c2cca JT |
544 | }; |
545 | ||
8e8be45e PM |
546 | /* |
547 | * RCU torture priority-boost testing. Runs one real-time thread per | |
548 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
549 | * spinning waiting for them to be invoked. If a given callback takes | |
550 | * too long to be invoked, we assume that priority inversion has occurred. | |
551 | */ | |
552 | ||
553 | struct rcu_boost_inflight { | |
554 | struct rcu_head rcu; | |
555 | int inflight; | |
556 | }; | |
557 | ||
558 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
559 | { | |
560 | struct rcu_boost_inflight *rbip = | |
561 | container_of(head, struct rcu_boost_inflight, rcu); | |
562 | ||
563 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
564 | rbip->inflight = 0; | |
565 | } | |
566 | ||
567 | static int rcu_torture_boost(void *arg) | |
568 | { | |
569 | unsigned long call_rcu_time; | |
570 | unsigned long endtime; | |
571 | unsigned long oldstarttime; | |
572 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
573 | struct sched_param sp; | |
574 | ||
5ccf60f2 | 575 | VERBOSE_TOROUT_STRING("rcu_torture_boost started"); |
8e8be45e PM |
576 | |
577 | /* Set real-time priority. */ | |
578 | sp.sched_priority = 1; | |
579 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
5ccf60f2 | 580 | VERBOSE_TOROUT_STRING("rcu_torture_boost RT prio failed!"); |
8e8be45e PM |
581 | n_rcu_torture_boost_rterror++; |
582 | } | |
583 | ||
561190e3 | 584 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
585 | /* Each pass through the following loop does one boost-test cycle. */ |
586 | do { | |
587 | /* Wait for the next test interval. */ | |
588 | oldstarttime = boost_starttime; | |
93898fb1 | 589 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
0e11c8e8 | 590 | schedule_timeout_interruptible(oldstarttime - jiffies); |
628edaa5 | 591 | stutter_wait("rcu_torture_boost"); |
36970bb9 | 592 | if (torture_must_stop()) |
8e8be45e PM |
593 | goto checkwait; |
594 | } | |
595 | ||
596 | /* Do one boost-test interval. */ | |
597 | endtime = oldstarttime + test_boost_duration * HZ; | |
598 | call_rcu_time = jiffies; | |
93898fb1 | 599 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e PM |
600 | /* If we don't have a callback in flight, post one. */ |
601 | if (!rbi.inflight) { | |
602 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
603 | rbi.inflight = 1; | |
604 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
605 | if (jiffies - call_rcu_time > | |
606 | test_boost_duration * HZ - HZ / 2) { | |
5ccf60f2 | 607 | VERBOSE_TOROUT_STRING("rcu_torture_boost boosting failed"); |
8e8be45e PM |
608 | n_rcu_torture_boost_failure++; |
609 | } | |
610 | call_rcu_time = jiffies; | |
611 | } | |
612 | cond_resched(); | |
628edaa5 | 613 | stutter_wait("rcu_torture_boost"); |
36970bb9 | 614 | if (torture_must_stop()) |
8e8be45e PM |
615 | goto checkwait; |
616 | } | |
617 | ||
618 | /* | |
619 | * Set the start time of the next test interval. | |
620 | * Yes, this is vulnerable to long delays, but such | |
621 | * delays simply cause a false negative for the next | |
622 | * interval. Besides, we are running at RT priority, | |
623 | * so delays should be relatively rare. | |
624 | */ | |
ab8f11e5 PM |
625 | while (oldstarttime == boost_starttime && |
626 | !kthread_should_stop()) { | |
8e8be45e PM |
627 | if (mutex_trylock(&boost_mutex)) { |
628 | boost_starttime = jiffies + | |
629 | test_boost_interval * HZ; | |
630 | n_rcu_torture_boosts++; | |
631 | mutex_unlock(&boost_mutex); | |
632 | break; | |
633 | } | |
634 | schedule_timeout_uninterruptible(1); | |
635 | } | |
636 | ||
637 | /* Go do the stutter. */ | |
628edaa5 | 638 | checkwait: stutter_wait("rcu_torture_boost"); |
36970bb9 | 639 | } while (!torture_must_stop()); |
8e8be45e PM |
640 | |
641 | /* Clean up and exit. */ | |
7fafaac5 PM |
642 | while (!kthread_should_stop() || rbi.inflight) { |
643 | torture_shutdown_absorb("rcu_torture_boost"); | |
8e8be45e | 644 | schedule_timeout_uninterruptible(1); |
7fafaac5 | 645 | } |
8e8be45e | 646 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ |
9d68197c | 647 | destroy_rcu_head_on_stack(&rbi.rcu); |
7fafaac5 | 648 | torture_kthread_stopping("rcu_torture_boost"); |
8e8be45e PM |
649 | return 0; |
650 | } | |
651 | ||
bf66f18e PM |
652 | /* |
653 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
654 | * bursts of calls to force_quiescent_state(), increasing the probability | |
655 | * of occurrence of some important types of race conditions. | |
656 | */ | |
657 | static int | |
658 | rcu_torture_fqs(void *arg) | |
659 | { | |
660 | unsigned long fqs_resume_time; | |
661 | int fqs_burst_remaining; | |
662 | ||
5ccf60f2 | 663 | VERBOSE_TOROUT_STRING("rcu_torture_fqs task started"); |
bf66f18e PM |
664 | do { |
665 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
666 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
667 | !kthread_should_stop()) { | |
bf66f18e PM |
668 | schedule_timeout_interruptible(1); |
669 | } | |
670 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
671 | while (fqs_burst_remaining > 0 && |
672 | !kthread_should_stop()) { | |
bf66f18e PM |
673 | cur_ops->fqs(); |
674 | udelay(fqs_holdoff); | |
675 | fqs_burst_remaining -= fqs_holdoff; | |
676 | } | |
628edaa5 | 677 | stutter_wait("rcu_torture_fqs"); |
36970bb9 | 678 | } while (!torture_must_stop()); |
7fafaac5 | 679 | torture_kthread_stopping("rcu_torture_fqs"); |
bf66f18e PM |
680 | return 0; |
681 | } | |
682 | ||
a241ec65 PM |
683 | /* |
684 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
685 | * for that pointed to by rcu_torture_current, freeing the old structure | |
686 | * after a series of grace periods (the "pipeline"). | |
687 | */ | |
688 | static int | |
689 | rcu_torture_writer(void *arg) | |
690 | { | |
2ec1f2d9 | 691 | bool exp; |
a241ec65 | 692 | int i; |
a241ec65 | 693 | struct rcu_torture *rp; |
2ec1f2d9 | 694 | struct rcu_torture *rp1; |
a241ec65 | 695 | struct rcu_torture *old_rp; |
51b1130e | 696 | static DEFINE_TORTURE_RANDOM(rand); |
a241ec65 | 697 | |
5ccf60f2 | 698 | VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); |
d277d868 | 699 | set_user_nice(current, MAX_NICE); |
dbdf65b1 | 700 | |
a241ec65 PM |
701 | do { |
702 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
703 | rp = rcu_torture_alloc(); |
704 | if (rp == NULL) | |
a241ec65 PM |
705 | continue; |
706 | rp->rtort_pipe_count = 0; | |
51b1130e | 707 | udelay(torture_random(&rand) & 0x3ff); |
0ddea0ea PM |
708 | old_rp = rcu_dereference_check(rcu_torture_current, |
709 | current == writer_task); | |
996417d2 | 710 | rp->rtort_mbtest = 1; |
a241ec65 | 711 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 712 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 713 | if (old_rp) { |
a241ec65 PM |
714 | i = old_rp->rtort_pipe_count; |
715 | if (i > RCU_TORTURE_PIPE_LEN) | |
716 | i = RCU_TORTURE_PIPE_LEN; | |
717 | atomic_inc(&rcu_torture_wcount[i]); | |
718 | old_rp->rtort_pipe_count++; | |
2ec1f2d9 | 719 | if (gp_normal == gp_exp) |
51b1130e | 720 | exp = !!(torture_random(&rand) & 0x80); |
2ec1f2d9 PM |
721 | else |
722 | exp = gp_exp; | |
723 | if (!exp) { | |
724 | cur_ops->deferred_free(old_rp); | |
725 | } else { | |
726 | cur_ops->exp_sync(); | |
727 | list_add(&old_rp->rtort_free, | |
728 | &rcu_torture_removed); | |
729 | list_for_each_entry_safe(rp, rp1, | |
730 | &rcu_torture_removed, | |
731 | rtort_free) { | |
732 | i = rp->rtort_pipe_count; | |
733 | if (i > RCU_TORTURE_PIPE_LEN) | |
734 | i = RCU_TORTURE_PIPE_LEN; | |
735 | atomic_inc(&rcu_torture_wcount[i]); | |
736 | if (++rp->rtort_pipe_count >= | |
737 | RCU_TORTURE_PIPE_LEN) { | |
738 | rp->rtort_mbtest = 0; | |
739 | list_del(&rp->rtort_free); | |
740 | rcu_torture_free(rp); | |
741 | } | |
742 | } | |
743 | } | |
a241ec65 | 744 | } |
4a298656 | 745 | rcutorture_record_progress(++rcu_torture_current_version); |
628edaa5 | 746 | stutter_wait("rcu_torture_writer"); |
36970bb9 | 747 | } while (!torture_must_stop()); |
7fafaac5 | 748 | torture_kthread_stopping("rcu_torture_writer"); |
a241ec65 PM |
749 | return 0; |
750 | } | |
751 | ||
b772e1dd JT |
752 | /* |
753 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
754 | * delay between calls. | |
755 | */ | |
756 | static int | |
757 | rcu_torture_fakewriter(void *arg) | |
758 | { | |
51b1130e | 759 | DEFINE_TORTURE_RANDOM(rand); |
b772e1dd | 760 | |
5ccf60f2 | 761 | VERBOSE_TOROUT_STRING("rcu_torture_fakewriter task started"); |
d277d868 | 762 | set_user_nice(current, MAX_NICE); |
b772e1dd JT |
763 | |
764 | do { | |
51b1130e PM |
765 | schedule_timeout_uninterruptible(1 + torture_random(&rand)%10); |
766 | udelay(torture_random(&rand) & 0x3ff); | |
72472a02 | 767 | if (cur_ops->cb_barrier != NULL && |
51b1130e | 768 | torture_random(&rand) % (nfakewriters * 8) == 0) { |
72472a02 | 769 | cur_ops->cb_barrier(); |
2ec1f2d9 | 770 | } else if (gp_normal == gp_exp) { |
51b1130e | 771 | if (torture_random(&rand) & 0x80) |
2ec1f2d9 PM |
772 | cur_ops->sync(); |
773 | else | |
774 | cur_ops->exp_sync(); | |
775 | } else if (gp_normal) { | |
72472a02 | 776 | cur_ops->sync(); |
2ec1f2d9 PM |
777 | } else { |
778 | cur_ops->exp_sync(); | |
779 | } | |
628edaa5 | 780 | stutter_wait("rcu_torture_fakewriter"); |
36970bb9 | 781 | } while (!torture_must_stop()); |
b772e1dd | 782 | |
7fafaac5 | 783 | torture_kthread_stopping("rcu_torture_fakewriter"); |
b772e1dd JT |
784 | return 0; |
785 | } | |
786 | ||
91afaf30 PM |
787 | void rcutorture_trace_dump(void) |
788 | { | |
789 | static atomic_t beenhere = ATOMIC_INIT(0); | |
790 | ||
791 | if (atomic_read(&beenhere)) | |
792 | return; | |
793 | if (atomic_xchg(&beenhere, 1) != 0) | |
794 | return; | |
91afaf30 PM |
795 | ftrace_dump(DUMP_ALL); |
796 | } | |
797 | ||
0729fbf3 PM |
798 | /* |
799 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
800 | * incrementing the corresponding element of the pipeline array. The | |
801 | * counter in the element should never be greater than 1, otherwise, the | |
802 | * RCU implementation is broken. | |
803 | */ | |
804 | static void rcu_torture_timer(unsigned long unused) | |
805 | { | |
806 | int idx; | |
807 | int completed; | |
52494535 | 808 | int completed_end; |
51b1130e | 809 | static DEFINE_TORTURE_RANDOM(rand); |
0729fbf3 PM |
810 | static DEFINE_SPINLOCK(rand_lock); |
811 | struct rcu_torture *p; | |
812 | int pipe_count; | |
52494535 | 813 | unsigned long long ts; |
0729fbf3 PM |
814 | |
815 | idx = cur_ops->readlock(); | |
816 | completed = cur_ops->completed(); | |
e4aa0da3 | 817 | ts = rcu_trace_clock_local(); |
632ee200 | 818 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
819 | rcu_read_lock_bh_held() || |
820 | rcu_read_lock_sched_held() || | |
821 | srcu_read_lock_held(&srcu_ctl)); | |
0729fbf3 PM |
822 | if (p == NULL) { |
823 | /* Leave because rcu_torture_writer is not yet underway */ | |
824 | cur_ops->readunlock(idx); | |
825 | return; | |
826 | } | |
827 | if (p->rtort_mbtest == 0) | |
828 | atomic_inc(&n_rcu_torture_mberror); | |
829 | spin_lock(&rand_lock); | |
0acc512c | 830 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
831 | n_rcu_torture_timers++; |
832 | spin_unlock(&rand_lock); | |
833 | preempt_disable(); | |
834 | pipe_count = p->rtort_pipe_count; | |
835 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
836 | /* Should not happen, but... */ | |
837 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
838 | } | |
52494535 PM |
839 | completed_end = cur_ops->completed(); |
840 | if (pipe_count > 1) { | |
52494535 PM |
841 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts, |
842 | completed, completed_end); | |
91afaf30 | 843 | rcutorture_trace_dump(); |
52494535 | 844 | } |
dd17c8f7 | 845 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
52494535 | 846 | completed = completed_end - completed; |
0729fbf3 PM |
847 | if (completed > RCU_TORTURE_PIPE_LEN) { |
848 | /* Should not happen, but... */ | |
849 | completed = RCU_TORTURE_PIPE_LEN; | |
850 | } | |
dd17c8f7 | 851 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
852 | preempt_enable(); |
853 | cur_ops->readunlock(idx); | |
854 | } | |
855 | ||
a241ec65 PM |
856 | /* |
857 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
858 | * incrementing the corresponding element of the pipeline array. The | |
859 | * counter in the element should never be greater than 1, otherwise, the | |
860 | * RCU implementation is broken. | |
861 | */ | |
862 | static int | |
863 | rcu_torture_reader(void *arg) | |
864 | { | |
865 | int completed; | |
52494535 | 866 | int completed_end; |
72e9bb54 | 867 | int idx; |
51b1130e | 868 | DEFINE_TORTURE_RANDOM(rand); |
a241ec65 PM |
869 | struct rcu_torture *p; |
870 | int pipe_count; | |
0729fbf3 | 871 | struct timer_list t; |
52494535 | 872 | unsigned long long ts; |
a241ec65 | 873 | |
5ccf60f2 | 874 | VERBOSE_TOROUT_STRING("rcu_torture_reader task started"); |
d277d868 | 875 | set_user_nice(current, MAX_NICE); |
0acc512c | 876 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 877 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 878 | |
a241ec65 | 879 | do { |
0acc512c | 880 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 881 | if (!timer_pending(&t)) |
6155fec9 | 882 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 883 | } |
72e9bb54 PM |
884 | idx = cur_ops->readlock(); |
885 | completed = cur_ops->completed(); | |
e4aa0da3 | 886 | ts = rcu_trace_clock_local(); |
632ee200 | 887 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
888 | rcu_read_lock_bh_held() || |
889 | rcu_read_lock_sched_held() || | |
890 | srcu_read_lock_held(&srcu_ctl)); | |
a241ec65 PM |
891 | if (p == NULL) { |
892 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 893 | cur_ops->readunlock(idx); |
a241ec65 PM |
894 | schedule_timeout_interruptible(HZ); |
895 | continue; | |
896 | } | |
996417d2 PM |
897 | if (p->rtort_mbtest == 0) |
898 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 899 | cur_ops->read_delay(&rand); |
a241ec65 PM |
900 | preempt_disable(); |
901 | pipe_count = p->rtort_pipe_count; | |
902 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
903 | /* Should not happen, but... */ | |
904 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
905 | } | |
52494535 PM |
906 | completed_end = cur_ops->completed(); |
907 | if (pipe_count > 1) { | |
52494535 PM |
908 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, |
909 | ts, completed, completed_end); | |
91afaf30 | 910 | rcutorture_trace_dump(); |
52494535 | 911 | } |
dd17c8f7 | 912 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
52494535 | 913 | completed = completed_end - completed; |
a241ec65 PM |
914 | if (completed > RCU_TORTURE_PIPE_LEN) { |
915 | /* Should not happen, but... */ | |
916 | completed = RCU_TORTURE_PIPE_LEN; | |
917 | } | |
dd17c8f7 | 918 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 919 | preempt_enable(); |
72e9bb54 | 920 | cur_ops->readunlock(idx); |
a241ec65 | 921 | schedule(); |
628edaa5 | 922 | stutter_wait("rcu_torture_reader"); |
36970bb9 | 923 | } while (!torture_must_stop()); |
0acc512c | 924 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 925 | del_timer_sync(&t); |
7fafaac5 | 926 | torture_kthread_stopping("rcu_torture_reader"); |
a241ec65 PM |
927 | return 0; |
928 | } | |
929 | ||
930 | /* | |
931 | * Create an RCU-torture statistics message in the specified buffer. | |
932 | */ | |
d1008950 | 933 | static void |
a241ec65 PM |
934 | rcu_torture_printk(char *page) |
935 | { | |
a241ec65 PM |
936 | int cpu; |
937 | int i; | |
938 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
939 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
940 | ||
0a945022 | 941 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
942 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
943 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
944 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
945 | } | |
946 | } | |
947 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
948 | if (pipesummary[i] != 0) | |
949 | break; | |
950 | } | |
d1008950 CG |
951 | page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG); |
952 | page += sprintf(page, | |
5cf05ad7 | 953 | "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", |
a241ec65 PM |
954 | rcu_torture_current, |
955 | rcu_torture_current_version, | |
956 | list_empty(&rcu_torture_freelist), | |
957 | atomic_read(&n_rcu_torture_alloc), | |
958 | atomic_read(&n_rcu_torture_alloc_fail), | |
5cf05ad7 | 959 | atomic_read(&n_rcu_torture_free)); |
d1008950 | 960 | page += sprintf(page, "rtmbe: %d rtbke: %ld rtbre: %ld ", |
0729fbf3 | 961 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e | 962 | n_rcu_torture_boost_ktrerror, |
5cf05ad7 | 963 | n_rcu_torture_boost_rterror); |
d1008950 | 964 | page += sprintf(page, "rtbf: %ld rtb: %ld nt: %ld ", |
8e8be45e PM |
965 | n_rcu_torture_boost_failure, |
966 | n_rcu_torture_boosts, | |
5cf05ad7 | 967 | n_rcu_torture_timers); |
2e9e8081 | 968 | page = torture_onoff_stats(page); |
d1008950 | 969 | page += sprintf(page, "barrier: %ld/%ld:%ld", |
fae4b54f PM |
970 | n_barrier_successes, |
971 | n_barrier_attempts, | |
972 | n_rcu_torture_barrier_error); | |
d1008950 | 973 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); |
8e8be45e | 974 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
fae4b54f | 975 | n_rcu_torture_barrier_error != 0 || |
8e8be45e PM |
976 | n_rcu_torture_boost_ktrerror != 0 || |
977 | n_rcu_torture_boost_rterror != 0 || | |
fae4b54f PM |
978 | n_rcu_torture_boost_failure != 0 || |
979 | i > 1) { | |
d1008950 | 980 | page += sprintf(page, "!!! "); |
996417d2 | 981 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 982 | WARN_ON_ONCE(1); |
996417d2 | 983 | } |
d1008950 | 984 | page += sprintf(page, "Reader Pipe: "); |
a241ec65 | 985 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
d1008950 CG |
986 | page += sprintf(page, " %ld", pipesummary[i]); |
987 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); | |
988 | page += sprintf(page, "Reader Batch: "); | |
72e9bb54 | 989 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
d1008950 CG |
990 | page += sprintf(page, " %ld", batchsummary[i]); |
991 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); | |
992 | page += sprintf(page, "Free-Block Circulation: "); | |
a241ec65 | 993 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
d1008950 | 994 | page += sprintf(page, " %d", |
a241ec65 PM |
995 | atomic_read(&rcu_torture_wcount[i])); |
996 | } | |
d1008950 | 997 | page += sprintf(page, "\n"); |
c8e5b163 | 998 | if (cur_ops->stats) |
d1008950 | 999 | cur_ops->stats(page); |
a241ec65 PM |
1000 | } |
1001 | ||
1002 | /* | |
1003 | * Print torture statistics. Caller must ensure that there is only | |
1004 | * one call to this function at a given time!!! This is normally | |
1005 | * accomplished by relying on the module system to only have one copy | |
1006 | * of the module loaded, and then by giving the rcu_torture_stats | |
1007 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1008 | * thread is not running). | |
1009 | */ | |
1010 | static void | |
1011 | rcu_torture_stats_print(void) | |
1012 | { | |
d1008950 CG |
1013 | int size = nr_cpu_ids * 200 + 8192; |
1014 | char *buf; | |
a241ec65 | 1015 | |
d1008950 CG |
1016 | buf = kmalloc(size, GFP_KERNEL); |
1017 | if (!buf) { | |
1018 | pr_err("rcu-torture: Out of memory, need: %d", size); | |
1019 | return; | |
1020 | } | |
1021 | rcu_torture_printk(buf); | |
1022 | pr_alert("%s", buf); | |
1023 | kfree(buf); | |
a241ec65 PM |
1024 | } |
1025 | ||
1026 | /* | |
1027 | * Periodically prints torture statistics, if periodic statistics printing | |
1028 | * was specified via the stat_interval module parameter. | |
a241ec65 PM |
1029 | */ |
1030 | static int | |
1031 | rcu_torture_stats(void *arg) | |
1032 | { | |
5ccf60f2 | 1033 | VERBOSE_TOROUT_STRING("rcu_torture_stats task started"); |
a241ec65 PM |
1034 | do { |
1035 | schedule_timeout_interruptible(stat_interval * HZ); | |
1036 | rcu_torture_stats_print(); | |
f67a3356 | 1037 | torture_shutdown_absorb("rcu_torture_stats"); |
36970bb9 | 1038 | } while (!torture_must_stop()); |
7fafaac5 | 1039 | torture_kthread_stopping("rcu_torture_stats"); |
d120f65f PM |
1040 | return 0; |
1041 | } | |
1042 | ||
95c38322 | 1043 | static inline void |
e66c33d5 | 1044 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) |
95c38322 | 1045 | { |
2caa1e44 PM |
1046 | pr_alert("%s" TORTURE_FLAG |
1047 | "--- %s: nreaders=%d nfakewriters=%d " | |
1048 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " | |
1049 | "shuffle_interval=%d stutter=%d irqreader=%d " | |
1050 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " | |
1051 | "test_boost=%d/%d test_boost_interval=%d " | |
1052 | "test_boost_duration=%d shutdown_secs=%d " | |
67afeed2 PM |
1053 | "stall_cpu=%d stall_cpu_holdoff=%d " |
1054 | "n_barrier_cbs=%d " | |
2caa1e44 PM |
1055 | "onoff_interval=%d onoff_holdoff=%d\n", |
1056 | torture_type, tag, nrealreaders, nfakewriters, | |
1057 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, | |
1058 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, | |
1059 | test_boost, cur_ops->can_boost, | |
1060 | test_boost_interval, test_boost_duration, shutdown_secs, | |
67afeed2 PM |
1061 | stall_cpu, stall_cpu_holdoff, |
1062 | n_barrier_cbs, | |
2caa1e44 | 1063 | onoff_interval, onoff_holdoff); |
95c38322 PM |
1064 | } |
1065 | ||
8e8be45e PM |
1066 | static void rcutorture_booster_cleanup(int cpu) |
1067 | { | |
1068 | struct task_struct *t; | |
1069 | ||
1070 | if (boost_tasks[cpu] == NULL) | |
1071 | return; | |
1072 | mutex_lock(&boost_mutex); | |
8e8be45e PM |
1073 | t = boost_tasks[cpu]; |
1074 | boost_tasks[cpu] = NULL; | |
1075 | mutex_unlock(&boost_mutex); | |
1076 | ||
1077 | /* This must be outside of the mutex, otherwise deadlock! */ | |
9c029b86 | 1078 | torture_stop_kthread(rcu_torture_boost, t); |
8e8be45e PM |
1079 | } |
1080 | ||
1081 | static int rcutorture_booster_init(int cpu) | |
1082 | { | |
1083 | int retval; | |
1084 | ||
1085 | if (boost_tasks[cpu] != NULL) | |
1086 | return 0; /* Already created, nothing more to do. */ | |
1087 | ||
1088 | /* Don't allow time recalculation while creating a new task. */ | |
1089 | mutex_lock(&boost_mutex); | |
5ccf60f2 | 1090 | VERBOSE_TOROUT_STRING("Creating rcu_torture_boost task"); |
1f288094 ED |
1091 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1092 | cpu_to_node(cpu), | |
1093 | "rcu_torture_boost"); | |
8e8be45e PM |
1094 | if (IS_ERR(boost_tasks[cpu])) { |
1095 | retval = PTR_ERR(boost_tasks[cpu]); | |
5ccf60f2 | 1096 | VERBOSE_TOROUT_STRING("rcu_torture_boost task create failed"); |
8e8be45e PM |
1097 | n_rcu_torture_boost_ktrerror++; |
1098 | boost_tasks[cpu] = NULL; | |
1099 | mutex_unlock(&boost_mutex); | |
1100 | return retval; | |
1101 | } | |
1102 | kthread_bind(boost_tasks[cpu], cpu); | |
1103 | wake_up_process(boost_tasks[cpu]); | |
1104 | mutex_unlock(&boost_mutex); | |
1105 | return 0; | |
1106 | } | |
1107 | ||
c13f3757 PM |
1108 | /* |
1109 | * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then | |
1110 | * induces a CPU stall for the time specified by stall_cpu. | |
1111 | */ | |
49fb4c62 | 1112 | static int rcu_torture_stall(void *args) |
c13f3757 PM |
1113 | { |
1114 | unsigned long stop_at; | |
1115 | ||
5ccf60f2 | 1116 | VERBOSE_TOROUT_STRING("rcu_torture_stall task started"); |
c13f3757 | 1117 | if (stall_cpu_holdoff > 0) { |
5ccf60f2 | 1118 | VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff"); |
c13f3757 | 1119 | schedule_timeout_interruptible(stall_cpu_holdoff * HZ); |
5ccf60f2 | 1120 | VERBOSE_TOROUT_STRING("rcu_torture_stall end holdoff"); |
c13f3757 PM |
1121 | } |
1122 | if (!kthread_should_stop()) { | |
1123 | stop_at = get_seconds() + stall_cpu; | |
1124 | /* RCU CPU stall is expected behavior in following code. */ | |
2caa1e44 | 1125 | pr_alert("rcu_torture_stall start.\n"); |
c13f3757 PM |
1126 | rcu_read_lock(); |
1127 | preempt_disable(); | |
1128 | while (ULONG_CMP_LT(get_seconds(), stop_at)) | |
1129 | continue; /* Induce RCU CPU stall warning. */ | |
1130 | preempt_enable(); | |
1131 | rcu_read_unlock(); | |
2caa1e44 | 1132 | pr_alert("rcu_torture_stall end.\n"); |
c13f3757 | 1133 | } |
f67a3356 | 1134 | torture_shutdown_absorb("rcu_torture_stall"); |
c13f3757 PM |
1135 | while (!kthread_should_stop()) |
1136 | schedule_timeout_interruptible(10 * HZ); | |
1137 | return 0; | |
1138 | } | |
1139 | ||
1140 | /* Spawn CPU-stall kthread, if stall_cpu specified. */ | |
1141 | static int __init rcu_torture_stall_init(void) | |
1142 | { | |
c13f3757 PM |
1143 | if (stall_cpu <= 0) |
1144 | return 0; | |
47cf29b9 | 1145 | return torture_create_kthread(rcu_torture_stall, NULL, stall_task); |
c13f3757 PM |
1146 | } |
1147 | ||
fae4b54f PM |
1148 | /* Callback function for RCU barrier testing. */ |
1149 | void rcu_torture_barrier_cbf(struct rcu_head *rcu) | |
1150 | { | |
1151 | atomic_inc(&barrier_cbs_invoked); | |
1152 | } | |
1153 | ||
1154 | /* kthread function to register callbacks used to test RCU barriers. */ | |
1155 | static int rcu_torture_barrier_cbs(void *arg) | |
1156 | { | |
1157 | long myid = (long)arg; | |
c6ebcbb6 | 1158 | bool lastphase = 0; |
78e4bc34 | 1159 | bool newphase; |
fae4b54f PM |
1160 | struct rcu_head rcu; |
1161 | ||
1162 | init_rcu_head_on_stack(&rcu); | |
5ccf60f2 | 1163 | VERBOSE_TOROUT_STRING("rcu_torture_barrier_cbs task started"); |
d277d868 | 1164 | set_user_nice(current, MAX_NICE); |
fae4b54f PM |
1165 | do { |
1166 | wait_event(barrier_cbs_wq[myid], | |
78e4bc34 PM |
1167 | (newphase = |
1168 | ACCESS_ONCE(barrier_phase)) != lastphase || | |
36970bb9 | 1169 | torture_must_stop()); |
78e4bc34 | 1170 | lastphase = newphase; |
c6ebcbb6 | 1171 | smp_mb(); /* ensure barrier_phase load before ->call(). */ |
36970bb9 | 1172 | if (torture_must_stop()) |
fae4b54f PM |
1173 | break; |
1174 | cur_ops->call(&rcu, rcu_torture_barrier_cbf); | |
1175 | if (atomic_dec_and_test(&barrier_cbs_count)) | |
1176 | wake_up(&barrier_wq); | |
36970bb9 | 1177 | } while (!torture_must_stop()); |
fae4b54f PM |
1178 | cur_ops->cb_barrier(); |
1179 | destroy_rcu_head_on_stack(&rcu); | |
7fafaac5 | 1180 | torture_kthread_stopping("rcu_torture_barrier_cbs"); |
fae4b54f PM |
1181 | return 0; |
1182 | } | |
1183 | ||
1184 | /* kthread function to drive and coordinate RCU barrier testing. */ | |
1185 | static int rcu_torture_barrier(void *arg) | |
1186 | { | |
1187 | int i; | |
1188 | ||
5ccf60f2 | 1189 | VERBOSE_TOROUT_STRING("rcu_torture_barrier task starting"); |
fae4b54f PM |
1190 | do { |
1191 | atomic_set(&barrier_cbs_invoked, 0); | |
1192 | atomic_set(&barrier_cbs_count, n_barrier_cbs); | |
c6ebcbb6 PM |
1193 | smp_mb(); /* Ensure barrier_phase after prior assignments. */ |
1194 | barrier_phase = !barrier_phase; | |
fae4b54f PM |
1195 | for (i = 0; i < n_barrier_cbs; i++) |
1196 | wake_up(&barrier_cbs_wq[i]); | |
1197 | wait_event(barrier_wq, | |
1198 | atomic_read(&barrier_cbs_count) == 0 || | |
36970bb9 PM |
1199 | torture_must_stop()); |
1200 | if (torture_must_stop()) | |
fae4b54f PM |
1201 | break; |
1202 | n_barrier_attempts++; | |
78e4bc34 | 1203 | cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */ |
fae4b54f PM |
1204 | if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { |
1205 | n_rcu_torture_barrier_error++; | |
1206 | WARN_ON_ONCE(1); | |
1207 | } | |
1208 | n_barrier_successes++; | |
1209 | schedule_timeout_interruptible(HZ / 10); | |
36970bb9 | 1210 | } while (!torture_must_stop()); |
7fafaac5 | 1211 | torture_kthread_stopping("rcu_torture_barrier"); |
fae4b54f PM |
1212 | return 0; |
1213 | } | |
1214 | ||
1215 | /* Initialize RCU barrier testing. */ | |
1216 | static int rcu_torture_barrier_init(void) | |
1217 | { | |
1218 | int i; | |
1219 | int ret; | |
1220 | ||
1221 | if (n_barrier_cbs == 0) | |
1222 | return 0; | |
1223 | if (cur_ops->call == NULL || cur_ops->cb_barrier == NULL) { | |
2caa1e44 PM |
1224 | pr_alert("%s" TORTURE_FLAG |
1225 | " Call or barrier ops missing for %s,\n", | |
1226 | torture_type, cur_ops->name); | |
1227 | pr_alert("%s" TORTURE_FLAG | |
1228 | " RCU barrier testing omitted from run.\n", | |
1229 | torture_type); | |
fae4b54f PM |
1230 | return 0; |
1231 | } | |
1232 | atomic_set(&barrier_cbs_count, 0); | |
1233 | atomic_set(&barrier_cbs_invoked, 0); | |
1234 | barrier_cbs_tasks = | |
1235 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_tasks[0]), | |
1236 | GFP_KERNEL); | |
1237 | barrier_cbs_wq = | |
1238 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_wq[0]), | |
1239 | GFP_KERNEL); | |
de5e6437 | 1240 | if (barrier_cbs_tasks == NULL || !barrier_cbs_wq) |
fae4b54f PM |
1241 | return -ENOMEM; |
1242 | for (i = 0; i < n_barrier_cbs; i++) { | |
1243 | init_waitqueue_head(&barrier_cbs_wq[i]); | |
47cf29b9 PM |
1244 | ret = torture_create_kthread(rcu_torture_barrier_cbs, |
1245 | (void *)(long)i, | |
1246 | barrier_cbs_tasks[i]); | |
1247 | if (ret) | |
fae4b54f | 1248 | return ret; |
fae4b54f | 1249 | } |
47cf29b9 | 1250 | return torture_create_kthread(rcu_torture_barrier, NULL, barrier_task); |
fae4b54f PM |
1251 | } |
1252 | ||
1253 | /* Clean up after RCU barrier testing. */ | |
1254 | static void rcu_torture_barrier_cleanup(void) | |
1255 | { | |
1256 | int i; | |
1257 | ||
9c029b86 | 1258 | torture_stop_kthread(rcu_torture_barrier, barrier_task); |
fae4b54f | 1259 | if (barrier_cbs_tasks != NULL) { |
9c029b86 PM |
1260 | for (i = 0; i < n_barrier_cbs; i++) |
1261 | torture_stop_kthread(rcu_torture_barrier_cbs, | |
1262 | barrier_cbs_tasks[i]); | |
fae4b54f PM |
1263 | kfree(barrier_cbs_tasks); |
1264 | barrier_cbs_tasks = NULL; | |
1265 | } | |
1266 | if (barrier_cbs_wq != NULL) { | |
1267 | kfree(barrier_cbs_wq); | |
1268 | barrier_cbs_wq = NULL; | |
1269 | } | |
1270 | } | |
1271 | ||
8e8be45e PM |
1272 | static int rcutorture_cpu_notify(struct notifier_block *self, |
1273 | unsigned long action, void *hcpu) | |
1274 | { | |
1275 | long cpu = (long)hcpu; | |
1276 | ||
1277 | switch (action) { | |
1278 | case CPU_ONLINE: | |
1279 | case CPU_DOWN_FAILED: | |
1280 | (void)rcutorture_booster_init(cpu); | |
1281 | break; | |
1282 | case CPU_DOWN_PREPARE: | |
1283 | rcutorture_booster_cleanup(cpu); | |
1284 | break; | |
1285 | default: | |
1286 | break; | |
1287 | } | |
1288 | return NOTIFY_OK; | |
1289 | } | |
1290 | ||
1291 | static struct notifier_block rcutorture_cpu_nb = { | |
1292 | .notifier_call = rcutorture_cpu_notify, | |
1293 | }; | |
1294 | ||
a241ec65 PM |
1295 | static void |
1296 | rcu_torture_cleanup(void) | |
1297 | { | |
1298 | int i; | |
1299 | ||
4a298656 | 1300 | rcutorture_record_test_transition(); |
cc47ae08 | 1301 | if (torture_cleanup()) { |
343e9099 PM |
1302 | if (cur_ops->cb_barrier != NULL) |
1303 | cur_ops->cb_barrier(); | |
1304 | return; | |
1305 | } | |
d84f5203 | 1306 | |
fae4b54f | 1307 | rcu_torture_barrier_cleanup(); |
9c029b86 | 1308 | torture_stop_kthread(rcu_torture_stall, stall_task); |
9c029b86 | 1309 | torture_stop_kthread(rcu_torture_writer, writer_task); |
a241ec65 | 1310 | |
c8e5b163 | 1311 | if (reader_tasks) { |
9c029b86 PM |
1312 | for (i = 0; i < nrealreaders; i++) |
1313 | torture_stop_kthread(rcu_torture_reader, | |
1314 | reader_tasks[i]); | |
a241ec65 | 1315 | kfree(reader_tasks); |
a241ec65 PM |
1316 | } |
1317 | rcu_torture_current = NULL; | |
1318 | ||
c8e5b163 | 1319 | if (fakewriter_tasks) { |
b772e1dd | 1320 | for (i = 0; i < nfakewriters; i++) { |
9c029b86 PM |
1321 | torture_stop_kthread(rcu_torture_fakewriter, |
1322 | fakewriter_tasks[i]); | |
b772e1dd JT |
1323 | } |
1324 | kfree(fakewriter_tasks); | |
1325 | fakewriter_tasks = NULL; | |
1326 | } | |
1327 | ||
9c029b86 PM |
1328 | torture_stop_kthread(rcu_torture_stats, stats_task); |
1329 | torture_stop_kthread(rcu_torture_fqs, fqs_task); | |
8e8be45e PM |
1330 | if ((test_boost == 1 && cur_ops->can_boost) || |
1331 | test_boost == 2) { | |
1332 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1333 | for_each_possible_cpu(i) | |
1334 | rcutorture_booster_cleanup(i); | |
1335 | } | |
bf66f18e | 1336 | |
a241ec65 | 1337 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1338 | |
1339 | if (cur_ops->cb_barrier != NULL) | |
1340 | cur_ops->cb_barrier(); | |
a241ec65 | 1341 | |
a241ec65 | 1342 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1343 | |
fae4b54f | 1344 | if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error) |
8e8be45e | 1345 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
2e9e8081 | 1346 | else if (torture_onoff_failures()) |
091541bb PM |
1347 | rcu_torture_print_module_parms(cur_ops, |
1348 | "End of test: RCU_HOTPLUG"); | |
95c38322 | 1349 | else |
8e8be45e | 1350 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1351 | } |
1352 | ||
d2818df1 PM |
1353 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD |
1354 | static void rcu_torture_leak_cb(struct rcu_head *rhp) | |
1355 | { | |
1356 | } | |
1357 | ||
1358 | static void rcu_torture_err_cb(struct rcu_head *rhp) | |
1359 | { | |
1360 | /* | |
1361 | * This -might- happen due to race conditions, but is unlikely. | |
1362 | * The scenario that leads to this happening is that the | |
1363 | * first of the pair of duplicate callbacks is queued, | |
1364 | * someone else starts a grace period that includes that | |
1365 | * callback, then the second of the pair must wait for the | |
1366 | * next grace period. Unlikely, but can happen. If it | |
1367 | * does happen, the debug-objects subsystem won't have splatted. | |
1368 | */ | |
1369 | pr_alert("rcutorture: duplicated callback was invoked.\n"); | |
1370 | } | |
1371 | #endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1372 | ||
1373 | /* | |
1374 | * Verify that double-free causes debug-objects to complain, but only | |
1375 | * if CONFIG_DEBUG_OBJECTS_RCU_HEAD=y. Otherwise, say that the test | |
1376 | * cannot be carried out. | |
1377 | */ | |
1378 | static void rcu_test_debug_objects(void) | |
1379 | { | |
1380 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD | |
1381 | struct rcu_head rh1; | |
1382 | struct rcu_head rh2; | |
1383 | ||
1384 | init_rcu_head_on_stack(&rh1); | |
1385 | init_rcu_head_on_stack(&rh2); | |
1386 | pr_alert("rcutorture: WARN: Duplicate call_rcu() test starting.\n"); | |
1387 | ||
1388 | /* Try to queue the rh2 pair of callbacks for the same grace period. */ | |
1389 | preempt_disable(); /* Prevent preemption from interrupting test. */ | |
1390 | rcu_read_lock(); /* Make it impossible to finish a grace period. */ | |
1391 | call_rcu(&rh1, rcu_torture_leak_cb); /* Start grace period. */ | |
1392 | local_irq_disable(); /* Make it harder to start a new grace period. */ | |
1393 | call_rcu(&rh2, rcu_torture_leak_cb); | |
1394 | call_rcu(&rh2, rcu_torture_err_cb); /* Duplicate callback. */ | |
1395 | local_irq_enable(); | |
1396 | rcu_read_unlock(); | |
1397 | preempt_enable(); | |
1398 | ||
1399 | /* Wait for them all to get done so we can safely return. */ | |
1400 | rcu_barrier(); | |
1401 | pr_alert("rcutorture: WARN: Duplicate call_rcu() test complete.\n"); | |
1402 | destroy_rcu_head_on_stack(&rh1); | |
1403 | destroy_rcu_head_on_stack(&rh2); | |
1404 | #else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1405 | pr_alert("rcutorture: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n"); | |
1406 | #endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1407 | } | |
1408 | ||
6f8bc500 | 1409 | static int __init |
a241ec65 PM |
1410 | rcu_torture_init(void) |
1411 | { | |
1412 | int i; | |
1413 | int cpu; | |
1414 | int firsterr = 0; | |
2ec1f2d9 | 1415 | static struct rcu_torture_ops *torture_ops[] = { |
ff20e251 | 1416 | &rcu_ops, &rcu_bh_ops, &rcu_busted_ops, &srcu_ops, &sched_ops, |
2ec1f2d9 | 1417 | }; |
a241ec65 | 1418 | |
628edaa5 | 1419 | torture_init_begin(torture_type, verbose, &rcutorture_runnable); |
343e9099 | 1420 | |
a241ec65 | 1421 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1422 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1423 | cur_ops = torture_ops[i]; |
ade5fb81 | 1424 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1425 | break; |
72e9bb54 | 1426 | } |
ade5fb81 | 1427 | if (i == ARRAY_SIZE(torture_ops)) { |
2caa1e44 PM |
1428 | pr_alert("rcu-torture: invalid torture type: \"%s\"\n", |
1429 | torture_type); | |
1430 | pr_alert("rcu-torture types:"); | |
cf886c44 | 1431 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) |
2caa1e44 PM |
1432 | pr_alert(" %s", torture_ops[i]->name); |
1433 | pr_alert("\n"); | |
b5daa8f3 | 1434 | torture_init_end(); |
a71fca58 | 1435 | return -EINVAL; |
72e9bb54 | 1436 | } |
bf66f18e | 1437 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
2caa1e44 | 1438 | pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); |
bf66f18e PM |
1439 | fqs_duration = 0; |
1440 | } | |
c8e5b163 | 1441 | if (cur_ops->init) |
72e9bb54 PM |
1442 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1443 | ||
a241ec65 PM |
1444 | if (nreaders >= 0) |
1445 | nrealreaders = nreaders; | |
1446 | else | |
1447 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1448 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
a241ec65 PM |
1449 | |
1450 | /* Set up the freelist. */ | |
1451 | ||
1452 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1453 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1454 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1455 | list_add_tail(&rcu_tortures[i].rtort_free, |
1456 | &rcu_torture_freelist); | |
1457 | } | |
1458 | ||
1459 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1460 | ||
1461 | rcu_torture_current = NULL; | |
1462 | rcu_torture_current_version = 0; | |
1463 | atomic_set(&n_rcu_torture_alloc, 0); | |
1464 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1465 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1466 | atomic_set(&n_rcu_torture_mberror, 0); |
1467 | atomic_set(&n_rcu_torture_error, 0); | |
fae4b54f | 1468 | n_rcu_torture_barrier_error = 0; |
8e8be45e PM |
1469 | n_rcu_torture_boost_ktrerror = 0; |
1470 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
1471 | n_rcu_torture_boost_failure = 0; |
1472 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1473 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1474 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1475 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1476 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1477 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1478 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1479 | } | |
1480 | } | |
1481 | ||
1482 | /* Start up the kthreads. */ | |
1483 | ||
47cf29b9 PM |
1484 | firsterr = torture_create_kthread(rcu_torture_writer, NULL, |
1485 | writer_task); | |
1486 | if (firsterr) | |
a241ec65 | 1487 | goto unwind; |
b772e1dd | 1488 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1489 | GFP_KERNEL); |
b772e1dd | 1490 | if (fakewriter_tasks == NULL) { |
5ccf60f2 | 1491 | VERBOSE_TOROUT_ERRSTRING("out of memory"); |
b772e1dd JT |
1492 | firsterr = -ENOMEM; |
1493 | goto unwind; | |
1494 | } | |
1495 | for (i = 0; i < nfakewriters; i++) { | |
47cf29b9 PM |
1496 | firsterr = torture_create_kthread(rcu_torture_fakewriter, |
1497 | NULL, fakewriter_tasks[i]); | |
1498 | if (firsterr) | |
b772e1dd | 1499 | goto unwind; |
b772e1dd | 1500 | } |
2860aaba | 1501 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1502 | GFP_KERNEL); |
1503 | if (reader_tasks == NULL) { | |
5ccf60f2 | 1504 | VERBOSE_TOROUT_ERRSTRING("out of memory"); |
a241ec65 PM |
1505 | firsterr = -ENOMEM; |
1506 | goto unwind; | |
1507 | } | |
1508 | for (i = 0; i < nrealreaders; i++) { | |
47cf29b9 PM |
1509 | firsterr = torture_create_kthread(rcu_torture_reader, NULL, |
1510 | reader_tasks[i]); | |
1511 | if (firsterr) | |
a241ec65 | 1512 | goto unwind; |
a241ec65 PM |
1513 | } |
1514 | if (stat_interval > 0) { | |
47cf29b9 PM |
1515 | firsterr = torture_create_kthread(rcu_torture_stats, NULL, |
1516 | stats_task); | |
1517 | if (firsterr) | |
a241ec65 | 1518 | goto unwind; |
a241ec65 | 1519 | } |
d84f5203 | 1520 | if (test_no_idle_hz) { |
3808dc9f PM |
1521 | firsterr = torture_shuffle_init(shuffle_interval * HZ); |
1522 | if (firsterr) | |
d84f5203 | 1523 | goto unwind; |
d84f5203 | 1524 | } |
d120f65f PM |
1525 | if (stutter < 0) |
1526 | stutter = 0; | |
1527 | if (stutter) { | |
628edaa5 PM |
1528 | firsterr = torture_stutter_init(stutter * HZ); |
1529 | if (firsterr) | |
d120f65f | 1530 | goto unwind; |
d120f65f | 1531 | } |
bf66f18e PM |
1532 | if (fqs_duration < 0) |
1533 | fqs_duration = 0; | |
1534 | if (fqs_duration) { | |
628edaa5 | 1535 | /* Create the fqs thread */ |
47cf29b9 PM |
1536 | torture_create_kthread(rcu_torture_fqs, NULL, fqs_task); |
1537 | if (firsterr) | |
bf66f18e | 1538 | goto unwind; |
bf66f18e | 1539 | } |
8e8be45e PM |
1540 | if (test_boost_interval < 1) |
1541 | test_boost_interval = 1; | |
1542 | if (test_boost_duration < 2) | |
1543 | test_boost_duration = 2; | |
1544 | if ((test_boost == 1 && cur_ops->can_boost) || | |
1545 | test_boost == 2) { | |
8e8be45e PM |
1546 | |
1547 | boost_starttime = jiffies + test_boost_interval * HZ; | |
1548 | register_cpu_notifier(&rcutorture_cpu_nb); | |
1549 | for_each_possible_cpu(i) { | |
1550 | if (cpu_is_offline(i)) | |
1551 | continue; /* Heuristic: CPU can go offline. */ | |
01025ebc PM |
1552 | firsterr = rcutorture_booster_init(i); |
1553 | if (firsterr) | |
8e8be45e | 1554 | goto unwind; |
8e8be45e PM |
1555 | } |
1556 | } | |
01025ebc PM |
1557 | firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup); |
1558 | if (firsterr) | |
37e377d2 | 1559 | goto unwind; |
01025ebc PM |
1560 | firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval * HZ); |
1561 | if (firsterr) | |
37e377d2 | 1562 | goto unwind; |
01025ebc PM |
1563 | firsterr = rcu_torture_stall_init(); |
1564 | if (firsterr) | |
37e377d2 | 1565 | goto unwind; |
01025ebc PM |
1566 | firsterr = rcu_torture_barrier_init(); |
1567 | if (firsterr) | |
fae4b54f | 1568 | goto unwind; |
d2818df1 PM |
1569 | if (object_debug) |
1570 | rcu_test_debug_objects(); | |
4a298656 | 1571 | rcutorture_record_test_transition(); |
b5daa8f3 | 1572 | torture_init_end(); |
a241ec65 PM |
1573 | return 0; |
1574 | ||
1575 | unwind: | |
b5daa8f3 | 1576 | torture_init_end(); |
a241ec65 PM |
1577 | rcu_torture_cleanup(); |
1578 | return firsterr; | |
1579 | } | |
1580 | ||
1581 | module_init(rcu_torture_init); | |
1582 | module_exit(rcu_torture_cleanup); |