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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 | |
ad0dc7f9 PM |
141 | static int rcu_torture_writer_state; |
142 | #define RTWS_FIXED_DELAY 0 | |
143 | #define RTWS_DELAY 1 | |
144 | #define RTWS_REPLACE 2 | |
145 | #define RTWS_DEF_FREE 3 | |
146 | #define RTWS_EXP_SYNC 4 | |
147 | #define RTWS_STUTTER 5 | |
148 | #define RTWS_STOPPING 6 | |
149 | ||
31a72bce PM |
150 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
151 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
152 | #else | |
153 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
154 | #endif | |
155 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
bb3bf705 PM |
156 | module_param(rcutorture_runnable, int, 0444); |
157 | MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot"); | |
31a72bce | 158 | |
3acf4a9a | 159 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 160 | #define rcu_can_boost() 1 |
3acf4a9a | 161 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 162 | #define rcu_can_boost() 0 |
3acf4a9a | 163 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 164 | |
e4aa0da3 SR |
165 | #ifdef CONFIG_RCU_TRACE |
166 | static u64 notrace rcu_trace_clock_local(void) | |
167 | { | |
168 | u64 ts = trace_clock_local(); | |
169 | unsigned long __maybe_unused ts_rem = do_div(ts, NSEC_PER_USEC); | |
170 | return ts; | |
171 | } | |
172 | #else /* #ifdef CONFIG_RCU_TRACE */ | |
173 | static u64 notrace rcu_trace_clock_local(void) | |
174 | { | |
175 | return 0ULL; | |
176 | } | |
177 | #endif /* #else #ifdef CONFIG_RCU_TRACE */ | |
178 | ||
8e8be45e PM |
179 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
180 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
181 | /* and boost task create/destroy. */ | |
fae4b54f | 182 | static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */ |
c6ebcbb6 | 183 | static bool barrier_phase; /* Test phase. */ |
fae4b54f PM |
184 | static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */ |
185 | static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */ | |
186 | static DECLARE_WAIT_QUEUE_HEAD(barrier_wq); | |
8e8be45e | 187 | |
a241ec65 PM |
188 | /* |
189 | * Allocate an element from the rcu_tortures pool. | |
190 | */ | |
97a41e26 | 191 | static struct rcu_torture * |
a241ec65 PM |
192 | rcu_torture_alloc(void) |
193 | { | |
194 | struct list_head *p; | |
195 | ||
adac1665 | 196 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
197 | if (list_empty(&rcu_torture_freelist)) { |
198 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 199 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
200 | return NULL; |
201 | } | |
202 | atomic_inc(&n_rcu_torture_alloc); | |
203 | p = rcu_torture_freelist.next; | |
204 | list_del_init(p); | |
adac1665 | 205 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
206 | return container_of(p, struct rcu_torture, rtort_free); |
207 | } | |
208 | ||
209 | /* | |
210 | * Free an element to the rcu_tortures pool. | |
211 | */ | |
212 | static void | |
213 | rcu_torture_free(struct rcu_torture *p) | |
214 | { | |
215 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 216 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 217 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 218 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
219 | } |
220 | ||
72e9bb54 PM |
221 | /* |
222 | * Operations vector for selecting different types of tests. | |
223 | */ | |
224 | ||
225 | struct rcu_torture_ops { | |
ad0dc7f9 | 226 | int ttype; |
72e9bb54 | 227 | void (*init)(void); |
72e9bb54 | 228 | int (*readlock)(void); |
51b1130e | 229 | void (*read_delay)(struct torture_random_state *rrsp); |
72e9bb54 PM |
230 | void (*readunlock)(int idx); |
231 | int (*completed)(void); | |
0acc512c | 232 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 233 | void (*sync)(void); |
2ec1f2d9 | 234 | void (*exp_sync)(void); |
fae4b54f | 235 | void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); |
2326974d | 236 | void (*cb_barrier)(void); |
bf66f18e | 237 | void (*fqs)(void); |
d1008950 | 238 | void (*stats)(char *page); |
0acc512c | 239 | int irq_capable; |
8e8be45e | 240 | int can_boost; |
e66c33d5 | 241 | const char *name; |
72e9bb54 | 242 | }; |
a71fca58 PM |
243 | |
244 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
245 | |
246 | /* | |
247 | * Definitions for rcu torture testing. | |
248 | */ | |
249 | ||
a49a4af7 | 250 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
251 | { |
252 | rcu_read_lock(); | |
253 | return 0; | |
254 | } | |
255 | ||
51b1130e | 256 | static void rcu_read_delay(struct torture_random_state *rrsp) |
b2896d2e | 257 | { |
b8d57a76 JT |
258 | const unsigned long shortdelay_us = 200; |
259 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 260 | |
b8d57a76 JT |
261 | /* We want a short delay sometimes to make a reader delay the grace |
262 | * period, and we want a long delay occasionally to trigger | |
263 | * force_quiescent_state. */ | |
b2896d2e | 264 | |
51b1130e | 265 | if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
b8d57a76 | 266 | mdelay(longdelay_ms); |
51b1130e | 267 | if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) |
b8d57a76 | 268 | udelay(shortdelay_us); |
e546f485 | 269 | #ifdef CONFIG_PREEMPT |
51b1130e PM |
270 | if (!preempt_count() && |
271 | !(torture_random(rrsp) % (nrealreaders * 20000))) | |
e546f485 LJ |
272 | preempt_schedule(); /* No QS if preempt_disable() in effect */ |
273 | #endif | |
b2896d2e PM |
274 | } |
275 | ||
a49a4af7 | 276 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
277 | { |
278 | rcu_read_unlock(); | |
279 | } | |
280 | ||
281 | static int rcu_torture_completed(void) | |
282 | { | |
283 | return rcu_batches_completed(); | |
284 | } | |
285 | ||
286 | static void | |
287 | rcu_torture_cb(struct rcu_head *p) | |
288 | { | |
289 | int i; | |
290 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
291 | ||
36970bb9 | 292 | if (torture_must_stop_irq()) { |
72e9bb54 PM |
293 | /* Test is ending, just drop callbacks on the floor. */ |
294 | /* The next initialization will pick up the pieces. */ | |
295 | return; | |
296 | } | |
297 | i = rp->rtort_pipe_count; | |
298 | if (i > RCU_TORTURE_PIPE_LEN) | |
299 | i = RCU_TORTURE_PIPE_LEN; | |
300 | atomic_inc(&rcu_torture_wcount[i]); | |
301 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
302 | rp->rtort_mbtest = 0; | |
303 | rcu_torture_free(rp); | |
c701d5d9 | 304 | } else { |
0acc512c | 305 | cur_ops->deferred_free(rp); |
c701d5d9 | 306 | } |
72e9bb54 PM |
307 | } |
308 | ||
d9a3da06 PM |
309 | static int rcu_no_completed(void) |
310 | { | |
311 | return 0; | |
312 | } | |
313 | ||
72e9bb54 PM |
314 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
315 | { | |
316 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
317 | } | |
318 | ||
e3033736 JT |
319 | static void rcu_sync_torture_init(void) |
320 | { | |
321 | INIT_LIST_HEAD(&rcu_torture_removed); | |
322 | } | |
323 | ||
2ec1f2d9 | 324 | static struct rcu_torture_ops rcu_ops = { |
ad0dc7f9 | 325 | .ttype = RCU_FLAVOR, |
0acc512c | 326 | .init = rcu_sync_torture_init, |
0acc512c PM |
327 | .readlock = rcu_torture_read_lock, |
328 | .read_delay = rcu_read_delay, | |
329 | .readunlock = rcu_torture_read_unlock, | |
330 | .completed = rcu_torture_completed, | |
2ec1f2d9 | 331 | .deferred_free = rcu_torture_deferred_free, |
0acc512c | 332 | .sync = synchronize_rcu, |
2ec1f2d9 PM |
333 | .exp_sync = synchronize_rcu_expedited, |
334 | .call = call_rcu, | |
335 | .cb_barrier = rcu_barrier, | |
bf66f18e | 336 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
337 | .stats = NULL, |
338 | .irq_capable = 1, | |
8e8be45e | 339 | .can_boost = rcu_can_boost(), |
2ec1f2d9 | 340 | .name = "rcu" |
d9a3da06 PM |
341 | }; |
342 | ||
c32e0660 PM |
343 | /* |
344 | * Definitions for rcu_bh torture testing. | |
345 | */ | |
346 | ||
a49a4af7 | 347 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
348 | { |
349 | rcu_read_lock_bh(); | |
350 | return 0; | |
351 | } | |
352 | ||
a49a4af7 | 353 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
354 | { |
355 | rcu_read_unlock_bh(); | |
356 | } | |
357 | ||
358 | static int rcu_bh_torture_completed(void) | |
359 | { | |
360 | return rcu_batches_completed_bh(); | |
361 | } | |
362 | ||
363 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
364 | { | |
365 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
366 | } | |
367 | ||
368 | static struct rcu_torture_ops rcu_bh_ops = { | |
ad0dc7f9 | 369 | .ttype = RCU_BH_FLAVOR, |
2ec1f2d9 | 370 | .init = rcu_sync_torture_init, |
0acc512c PM |
371 | .readlock = rcu_bh_torture_read_lock, |
372 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
373 | .readunlock = rcu_bh_torture_read_unlock, | |
374 | .completed = rcu_bh_torture_completed, | |
375 | .deferred_free = rcu_bh_torture_deferred_free, | |
bdf2a436 | 376 | .sync = synchronize_rcu_bh, |
2ec1f2d9 | 377 | .exp_sync = synchronize_rcu_bh_expedited, |
fae4b54f | 378 | .call = call_rcu_bh, |
0acc512c | 379 | .cb_barrier = rcu_barrier_bh, |
bf66f18e | 380 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
381 | .stats = NULL, |
382 | .irq_capable = 1, | |
383 | .name = "rcu_bh" | |
c32e0660 PM |
384 | }; |
385 | ||
ff20e251 PM |
386 | /* |
387 | * Don't even think about trying any of these in real life!!! | |
388 | * The names includes "busted", and they really means it! | |
389 | * The only purpose of these functions is to provide a buggy RCU | |
390 | * implementation to make sure that rcutorture correctly emits | |
391 | * buggy-RCU error messages. | |
392 | */ | |
393 | static void rcu_busted_torture_deferred_free(struct rcu_torture *p) | |
394 | { | |
395 | /* This is a deliberate bug for testing purposes only! */ | |
396 | rcu_torture_cb(&p->rtort_rcu); | |
397 | } | |
398 | ||
399 | static void synchronize_rcu_busted(void) | |
400 | { | |
401 | /* This is a deliberate bug for testing purposes only! */ | |
402 | } | |
403 | ||
404 | static void | |
405 | call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) | |
406 | { | |
407 | /* This is a deliberate bug for testing purposes only! */ | |
408 | func(head); | |
409 | } | |
410 | ||
411 | static struct rcu_torture_ops rcu_busted_ops = { | |
ad0dc7f9 | 412 | .ttype = INVALID_RCU_FLAVOR, |
ff20e251 PM |
413 | .init = rcu_sync_torture_init, |
414 | .readlock = rcu_torture_read_lock, | |
415 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
416 | .readunlock = rcu_torture_read_unlock, | |
417 | .completed = rcu_no_completed, | |
418 | .deferred_free = rcu_busted_torture_deferred_free, | |
419 | .sync = synchronize_rcu_busted, | |
420 | .exp_sync = synchronize_rcu_busted, | |
421 | .call = call_rcu_busted, | |
422 | .cb_barrier = NULL, | |
423 | .fqs = NULL, | |
424 | .stats = NULL, | |
425 | .irq_capable = 1, | |
426 | .name = "rcu_busted" | |
427 | }; | |
428 | ||
b2896d2e PM |
429 | /* |
430 | * Definitions for srcu torture testing. | |
431 | */ | |
432 | ||
cda4dc81 | 433 | DEFINE_STATIC_SRCU(srcu_ctl); |
b2896d2e | 434 | |
012d3ca8 | 435 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
436 | { |
437 | return srcu_read_lock(&srcu_ctl); | |
438 | } | |
439 | ||
51b1130e | 440 | static void srcu_read_delay(struct torture_random_state *rrsp) |
b2896d2e PM |
441 | { |
442 | long delay; | |
443 | const long uspertick = 1000000 / HZ; | |
444 | const long longdelay = 10; | |
445 | ||
446 | /* We want there to be long-running readers, but not all the time. */ | |
447 | ||
51b1130e PM |
448 | delay = torture_random(rrsp) % |
449 | (nrealreaders * 2 * longdelay * uspertick); | |
b2896d2e PM |
450 | if (!delay) |
451 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
452 | else |
453 | rcu_read_delay(rrsp); | |
b2896d2e PM |
454 | } |
455 | ||
012d3ca8 | 456 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
457 | { |
458 | srcu_read_unlock(&srcu_ctl, idx); | |
459 | } | |
460 | ||
461 | static int srcu_torture_completed(void) | |
462 | { | |
463 | return srcu_batches_completed(&srcu_ctl); | |
464 | } | |
465 | ||
9059c940 LJ |
466 | static void srcu_torture_deferred_free(struct rcu_torture *rp) |
467 | { | |
468 | call_srcu(&srcu_ctl, &rp->rtort_rcu, rcu_torture_cb); | |
469 | } | |
470 | ||
b772e1dd JT |
471 | static void srcu_torture_synchronize(void) |
472 | { | |
473 | synchronize_srcu(&srcu_ctl); | |
474 | } | |
475 | ||
e3f8d378 PM |
476 | static void srcu_torture_call(struct rcu_head *head, |
477 | void (*func)(struct rcu_head *head)) | |
478 | { | |
479 | call_srcu(&srcu_ctl, head, func); | |
480 | } | |
481 | ||
482 | static void srcu_torture_barrier(void) | |
483 | { | |
484 | srcu_barrier(&srcu_ctl); | |
485 | } | |
486 | ||
d1008950 | 487 | static void srcu_torture_stats(char *page) |
b2896d2e | 488 | { |
b2896d2e PM |
489 | int cpu; |
490 | int idx = srcu_ctl.completed & 0x1; | |
491 | ||
d1008950 | 492 | page += sprintf(page, "%s%s per-CPU(idx=%d):", |
b2896d2e PM |
493 | torture_type, TORTURE_FLAG, idx); |
494 | for_each_possible_cpu(cpu) { | |
d1008950 | 495 | page += sprintf(page, " %d(%lu,%lu)", cpu, |
b2896d2e PM |
496 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], |
497 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
498 | } | |
d1008950 | 499 | sprintf(page, "\n"); |
b2896d2e PM |
500 | } |
501 | ||
2ec1f2d9 PM |
502 | static void srcu_torture_synchronize_expedited(void) |
503 | { | |
504 | synchronize_srcu_expedited(&srcu_ctl); | |
505 | } | |
506 | ||
b2896d2e | 507 | static struct rcu_torture_ops srcu_ops = { |
ad0dc7f9 | 508 | .ttype = SRCU_FLAVOR, |
cda4dc81 | 509 | .init = rcu_sync_torture_init, |
0acc512c PM |
510 | .readlock = srcu_torture_read_lock, |
511 | .read_delay = srcu_read_delay, | |
512 | .readunlock = srcu_torture_read_unlock, | |
513 | .completed = srcu_torture_completed, | |
9059c940 | 514 | .deferred_free = srcu_torture_deferred_free, |
0acc512c | 515 | .sync = srcu_torture_synchronize, |
2ec1f2d9 | 516 | .exp_sync = srcu_torture_synchronize_expedited, |
e3f8d378 PM |
517 | .call = srcu_torture_call, |
518 | .cb_barrier = srcu_torture_barrier, | |
0acc512c PM |
519 | .stats = srcu_torture_stats, |
520 | .name = "srcu" | |
b2896d2e PM |
521 | }; |
522 | ||
4b6c2cca JT |
523 | /* |
524 | * Definitions for sched torture testing. | |
525 | */ | |
526 | ||
527 | static int sched_torture_read_lock(void) | |
528 | { | |
529 | preempt_disable(); | |
530 | return 0; | |
531 | } | |
532 | ||
533 | static void sched_torture_read_unlock(int idx) | |
534 | { | |
535 | preempt_enable(); | |
536 | } | |
537 | ||
2326974d PM |
538 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
539 | { | |
540 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
541 | } | |
542 | ||
4b6c2cca | 543 | static struct rcu_torture_ops sched_ops = { |
ad0dc7f9 | 544 | .ttype = RCU_SCHED_FLAVOR, |
0acc512c | 545 | .init = rcu_sync_torture_init, |
0acc512c PM |
546 | .readlock = sched_torture_read_lock, |
547 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
548 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 549 | .completed = rcu_no_completed, |
0acc512c | 550 | .deferred_free = rcu_sched_torture_deferred_free, |
bdf2a436 | 551 | .sync = synchronize_sched, |
2ec1f2d9 PM |
552 | .exp_sync = synchronize_sched_expedited, |
553 | .call = call_rcu_sched, | |
0acc512c | 554 | .cb_barrier = rcu_barrier_sched, |
bf66f18e | 555 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
556 | .stats = NULL, |
557 | .irq_capable = 1, | |
558 | .name = "sched" | |
4b6c2cca JT |
559 | }; |
560 | ||
8e8be45e PM |
561 | /* |
562 | * RCU torture priority-boost testing. Runs one real-time thread per | |
563 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
564 | * spinning waiting for them to be invoked. If a given callback takes | |
565 | * too long to be invoked, we assume that priority inversion has occurred. | |
566 | */ | |
567 | ||
568 | struct rcu_boost_inflight { | |
569 | struct rcu_head rcu; | |
570 | int inflight; | |
571 | }; | |
572 | ||
573 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
574 | { | |
575 | struct rcu_boost_inflight *rbip = | |
576 | container_of(head, struct rcu_boost_inflight, rcu); | |
577 | ||
578 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
579 | rbip->inflight = 0; | |
580 | } | |
581 | ||
582 | static int rcu_torture_boost(void *arg) | |
583 | { | |
584 | unsigned long call_rcu_time; | |
585 | unsigned long endtime; | |
586 | unsigned long oldstarttime; | |
587 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
588 | struct sched_param sp; | |
589 | ||
5ccf60f2 | 590 | VERBOSE_TOROUT_STRING("rcu_torture_boost started"); |
8e8be45e PM |
591 | |
592 | /* Set real-time priority. */ | |
593 | sp.sched_priority = 1; | |
594 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
5ccf60f2 | 595 | VERBOSE_TOROUT_STRING("rcu_torture_boost RT prio failed!"); |
8e8be45e PM |
596 | n_rcu_torture_boost_rterror++; |
597 | } | |
598 | ||
561190e3 | 599 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
600 | /* Each pass through the following loop does one boost-test cycle. */ |
601 | do { | |
602 | /* Wait for the next test interval. */ | |
603 | oldstarttime = boost_starttime; | |
93898fb1 | 604 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
0e11c8e8 | 605 | schedule_timeout_interruptible(oldstarttime - jiffies); |
628edaa5 | 606 | stutter_wait("rcu_torture_boost"); |
36970bb9 | 607 | if (torture_must_stop()) |
8e8be45e PM |
608 | goto checkwait; |
609 | } | |
610 | ||
611 | /* Do one boost-test interval. */ | |
612 | endtime = oldstarttime + test_boost_duration * HZ; | |
613 | call_rcu_time = jiffies; | |
93898fb1 | 614 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e PM |
615 | /* If we don't have a callback in flight, post one. */ |
616 | if (!rbi.inflight) { | |
617 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
618 | rbi.inflight = 1; | |
619 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
620 | if (jiffies - call_rcu_time > | |
621 | test_boost_duration * HZ - HZ / 2) { | |
5ccf60f2 | 622 | VERBOSE_TOROUT_STRING("rcu_torture_boost boosting failed"); |
8e8be45e PM |
623 | n_rcu_torture_boost_failure++; |
624 | } | |
625 | call_rcu_time = jiffies; | |
626 | } | |
627 | cond_resched(); | |
628edaa5 | 628 | stutter_wait("rcu_torture_boost"); |
36970bb9 | 629 | if (torture_must_stop()) |
8e8be45e PM |
630 | goto checkwait; |
631 | } | |
632 | ||
633 | /* | |
634 | * Set the start time of the next test interval. | |
635 | * Yes, this is vulnerable to long delays, but such | |
636 | * delays simply cause a false negative for the next | |
637 | * interval. Besides, we are running at RT priority, | |
638 | * so delays should be relatively rare. | |
639 | */ | |
ab8f11e5 PM |
640 | while (oldstarttime == boost_starttime && |
641 | !kthread_should_stop()) { | |
8e8be45e PM |
642 | if (mutex_trylock(&boost_mutex)) { |
643 | boost_starttime = jiffies + | |
644 | test_boost_interval * HZ; | |
645 | n_rcu_torture_boosts++; | |
646 | mutex_unlock(&boost_mutex); | |
647 | break; | |
648 | } | |
649 | schedule_timeout_uninterruptible(1); | |
650 | } | |
651 | ||
652 | /* Go do the stutter. */ | |
628edaa5 | 653 | checkwait: stutter_wait("rcu_torture_boost"); |
36970bb9 | 654 | } while (!torture_must_stop()); |
8e8be45e PM |
655 | |
656 | /* Clean up and exit. */ | |
7fafaac5 PM |
657 | while (!kthread_should_stop() || rbi.inflight) { |
658 | torture_shutdown_absorb("rcu_torture_boost"); | |
8e8be45e | 659 | schedule_timeout_uninterruptible(1); |
7fafaac5 | 660 | } |
8e8be45e | 661 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ |
9d68197c | 662 | destroy_rcu_head_on_stack(&rbi.rcu); |
7fafaac5 | 663 | torture_kthread_stopping("rcu_torture_boost"); |
8e8be45e PM |
664 | return 0; |
665 | } | |
666 | ||
bf66f18e PM |
667 | /* |
668 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
669 | * bursts of calls to force_quiescent_state(), increasing the probability | |
670 | * of occurrence of some important types of race conditions. | |
671 | */ | |
672 | static int | |
673 | rcu_torture_fqs(void *arg) | |
674 | { | |
675 | unsigned long fqs_resume_time; | |
676 | int fqs_burst_remaining; | |
677 | ||
5ccf60f2 | 678 | VERBOSE_TOROUT_STRING("rcu_torture_fqs task started"); |
bf66f18e PM |
679 | do { |
680 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
681 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
682 | !kthread_should_stop()) { | |
bf66f18e PM |
683 | schedule_timeout_interruptible(1); |
684 | } | |
685 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
686 | while (fqs_burst_remaining > 0 && |
687 | !kthread_should_stop()) { | |
bf66f18e PM |
688 | cur_ops->fqs(); |
689 | udelay(fqs_holdoff); | |
690 | fqs_burst_remaining -= fqs_holdoff; | |
691 | } | |
628edaa5 | 692 | stutter_wait("rcu_torture_fqs"); |
36970bb9 | 693 | } while (!torture_must_stop()); |
7fafaac5 | 694 | torture_kthread_stopping("rcu_torture_fqs"); |
bf66f18e PM |
695 | return 0; |
696 | } | |
697 | ||
a241ec65 PM |
698 | /* |
699 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
700 | * for that pointed to by rcu_torture_current, freeing the old structure | |
701 | * after a series of grace periods (the "pipeline"). | |
702 | */ | |
703 | static int | |
704 | rcu_torture_writer(void *arg) | |
705 | { | |
2ec1f2d9 | 706 | bool exp; |
a241ec65 | 707 | int i; |
a241ec65 | 708 | struct rcu_torture *rp; |
2ec1f2d9 | 709 | struct rcu_torture *rp1; |
a241ec65 | 710 | struct rcu_torture *old_rp; |
51b1130e | 711 | static DEFINE_TORTURE_RANDOM(rand); |
a241ec65 | 712 | |
5ccf60f2 | 713 | VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); |
d277d868 | 714 | set_user_nice(current, MAX_NICE); |
dbdf65b1 | 715 | |
a241ec65 | 716 | do { |
ad0dc7f9 | 717 | rcu_torture_writer_state = RTWS_FIXED_DELAY; |
a241ec65 | 718 | schedule_timeout_uninterruptible(1); |
a71fca58 PM |
719 | rp = rcu_torture_alloc(); |
720 | if (rp == NULL) | |
a241ec65 PM |
721 | continue; |
722 | rp->rtort_pipe_count = 0; | |
ad0dc7f9 | 723 | rcu_torture_writer_state = RTWS_DELAY; |
51b1130e | 724 | udelay(torture_random(&rand) & 0x3ff); |
ad0dc7f9 | 725 | rcu_torture_writer_state = RTWS_REPLACE; |
0ddea0ea PM |
726 | old_rp = rcu_dereference_check(rcu_torture_current, |
727 | current == writer_task); | |
996417d2 | 728 | rp->rtort_mbtest = 1; |
a241ec65 | 729 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 730 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 731 | if (old_rp) { |
a241ec65 PM |
732 | i = old_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 | old_rp->rtort_pipe_count++; | |
2ec1f2d9 | 737 | if (gp_normal == gp_exp) |
51b1130e | 738 | exp = !!(torture_random(&rand) & 0x80); |
2ec1f2d9 PM |
739 | else |
740 | exp = gp_exp; | |
741 | if (!exp) { | |
ad0dc7f9 | 742 | rcu_torture_writer_state = RTWS_DEF_FREE; |
2ec1f2d9 PM |
743 | cur_ops->deferred_free(old_rp); |
744 | } else { | |
ad0dc7f9 | 745 | rcu_torture_writer_state = RTWS_EXP_SYNC; |
2ec1f2d9 PM |
746 | cur_ops->exp_sync(); |
747 | list_add(&old_rp->rtort_free, | |
748 | &rcu_torture_removed); | |
749 | list_for_each_entry_safe(rp, rp1, | |
750 | &rcu_torture_removed, | |
751 | rtort_free) { | |
752 | i = rp->rtort_pipe_count; | |
753 | if (i > RCU_TORTURE_PIPE_LEN) | |
754 | i = RCU_TORTURE_PIPE_LEN; | |
755 | atomic_inc(&rcu_torture_wcount[i]); | |
756 | if (++rp->rtort_pipe_count >= | |
757 | RCU_TORTURE_PIPE_LEN) { | |
758 | rp->rtort_mbtest = 0; | |
759 | list_del(&rp->rtort_free); | |
760 | rcu_torture_free(rp); | |
761 | } | |
762 | } | |
763 | } | |
a241ec65 | 764 | } |
4a298656 | 765 | rcutorture_record_progress(++rcu_torture_current_version); |
ad0dc7f9 | 766 | rcu_torture_writer_state = RTWS_STUTTER; |
628edaa5 | 767 | stutter_wait("rcu_torture_writer"); |
36970bb9 | 768 | } while (!torture_must_stop()); |
ad0dc7f9 | 769 | rcu_torture_writer_state = RTWS_STOPPING; |
7fafaac5 | 770 | torture_kthread_stopping("rcu_torture_writer"); |
a241ec65 PM |
771 | return 0; |
772 | } | |
773 | ||
b772e1dd JT |
774 | /* |
775 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
776 | * delay between calls. | |
777 | */ | |
778 | static int | |
779 | rcu_torture_fakewriter(void *arg) | |
780 | { | |
51b1130e | 781 | DEFINE_TORTURE_RANDOM(rand); |
b772e1dd | 782 | |
5ccf60f2 | 783 | VERBOSE_TOROUT_STRING("rcu_torture_fakewriter task started"); |
d277d868 | 784 | set_user_nice(current, MAX_NICE); |
b772e1dd JT |
785 | |
786 | do { | |
51b1130e PM |
787 | schedule_timeout_uninterruptible(1 + torture_random(&rand)%10); |
788 | udelay(torture_random(&rand) & 0x3ff); | |
72472a02 | 789 | if (cur_ops->cb_barrier != NULL && |
51b1130e | 790 | torture_random(&rand) % (nfakewriters * 8) == 0) { |
72472a02 | 791 | cur_ops->cb_barrier(); |
2ec1f2d9 | 792 | } else if (gp_normal == gp_exp) { |
51b1130e | 793 | if (torture_random(&rand) & 0x80) |
2ec1f2d9 PM |
794 | cur_ops->sync(); |
795 | else | |
796 | cur_ops->exp_sync(); | |
797 | } else if (gp_normal) { | |
72472a02 | 798 | cur_ops->sync(); |
2ec1f2d9 PM |
799 | } else { |
800 | cur_ops->exp_sync(); | |
801 | } | |
628edaa5 | 802 | stutter_wait("rcu_torture_fakewriter"); |
36970bb9 | 803 | } while (!torture_must_stop()); |
b772e1dd | 804 | |
7fafaac5 | 805 | torture_kthread_stopping("rcu_torture_fakewriter"); |
b772e1dd JT |
806 | return 0; |
807 | } | |
808 | ||
b3b8a4d4 | 809 | static void rcutorture_trace_dump(void) |
91afaf30 PM |
810 | { |
811 | static atomic_t beenhere = ATOMIC_INIT(0); | |
812 | ||
813 | if (atomic_read(&beenhere)) | |
814 | return; | |
815 | if (atomic_xchg(&beenhere, 1) != 0) | |
816 | return; | |
91afaf30 PM |
817 | ftrace_dump(DUMP_ALL); |
818 | } | |
819 | ||
0729fbf3 PM |
820 | /* |
821 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
822 | * incrementing the corresponding element of the pipeline array. The | |
823 | * counter in the element should never be greater than 1, otherwise, the | |
824 | * RCU implementation is broken. | |
825 | */ | |
826 | static void rcu_torture_timer(unsigned long unused) | |
827 | { | |
828 | int idx; | |
829 | int completed; | |
52494535 | 830 | int completed_end; |
51b1130e | 831 | static DEFINE_TORTURE_RANDOM(rand); |
0729fbf3 PM |
832 | static DEFINE_SPINLOCK(rand_lock); |
833 | struct rcu_torture *p; | |
834 | int pipe_count; | |
52494535 | 835 | unsigned long long ts; |
0729fbf3 PM |
836 | |
837 | idx = cur_ops->readlock(); | |
838 | completed = cur_ops->completed(); | |
e4aa0da3 | 839 | ts = rcu_trace_clock_local(); |
632ee200 | 840 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
841 | rcu_read_lock_bh_held() || |
842 | rcu_read_lock_sched_held() || | |
843 | srcu_read_lock_held(&srcu_ctl)); | |
0729fbf3 PM |
844 | if (p == NULL) { |
845 | /* Leave because rcu_torture_writer is not yet underway */ | |
846 | cur_ops->readunlock(idx); | |
847 | return; | |
848 | } | |
849 | if (p->rtort_mbtest == 0) | |
850 | atomic_inc(&n_rcu_torture_mberror); | |
851 | spin_lock(&rand_lock); | |
0acc512c | 852 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
853 | n_rcu_torture_timers++; |
854 | spin_unlock(&rand_lock); | |
855 | preempt_disable(); | |
856 | pipe_count = p->rtort_pipe_count; | |
857 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
858 | /* Should not happen, but... */ | |
859 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
860 | } | |
52494535 PM |
861 | completed_end = cur_ops->completed(); |
862 | if (pipe_count > 1) { | |
52494535 PM |
863 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts, |
864 | completed, completed_end); | |
91afaf30 | 865 | rcutorture_trace_dump(); |
52494535 | 866 | } |
dd17c8f7 | 867 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
52494535 | 868 | completed = completed_end - completed; |
0729fbf3 PM |
869 | if (completed > RCU_TORTURE_PIPE_LEN) { |
870 | /* Should not happen, but... */ | |
871 | completed = RCU_TORTURE_PIPE_LEN; | |
872 | } | |
dd17c8f7 | 873 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
874 | preempt_enable(); |
875 | cur_ops->readunlock(idx); | |
876 | } | |
877 | ||
a241ec65 PM |
878 | /* |
879 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
880 | * incrementing the corresponding element of the pipeline array. The | |
881 | * counter in the element should never be greater than 1, otherwise, the | |
882 | * RCU implementation is broken. | |
883 | */ | |
884 | static int | |
885 | rcu_torture_reader(void *arg) | |
886 | { | |
887 | int completed; | |
52494535 | 888 | int completed_end; |
72e9bb54 | 889 | int idx; |
51b1130e | 890 | DEFINE_TORTURE_RANDOM(rand); |
a241ec65 PM |
891 | struct rcu_torture *p; |
892 | int pipe_count; | |
0729fbf3 | 893 | struct timer_list t; |
52494535 | 894 | unsigned long long ts; |
a241ec65 | 895 | |
5ccf60f2 | 896 | VERBOSE_TOROUT_STRING("rcu_torture_reader task started"); |
d277d868 | 897 | set_user_nice(current, MAX_NICE); |
0acc512c | 898 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 899 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 900 | |
a241ec65 | 901 | do { |
0acc512c | 902 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 903 | if (!timer_pending(&t)) |
6155fec9 | 904 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 905 | } |
72e9bb54 PM |
906 | idx = cur_ops->readlock(); |
907 | completed = cur_ops->completed(); | |
e4aa0da3 | 908 | ts = rcu_trace_clock_local(); |
632ee200 | 909 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
910 | rcu_read_lock_bh_held() || |
911 | rcu_read_lock_sched_held() || | |
912 | srcu_read_lock_held(&srcu_ctl)); | |
a241ec65 PM |
913 | if (p == NULL) { |
914 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 915 | cur_ops->readunlock(idx); |
a241ec65 PM |
916 | schedule_timeout_interruptible(HZ); |
917 | continue; | |
918 | } | |
996417d2 PM |
919 | if (p->rtort_mbtest == 0) |
920 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 921 | cur_ops->read_delay(&rand); |
a241ec65 PM |
922 | preempt_disable(); |
923 | pipe_count = p->rtort_pipe_count; | |
924 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
925 | /* Should not happen, but... */ | |
926 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
927 | } | |
52494535 PM |
928 | completed_end = cur_ops->completed(); |
929 | if (pipe_count > 1) { | |
52494535 PM |
930 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, |
931 | ts, completed, completed_end); | |
91afaf30 | 932 | rcutorture_trace_dump(); |
52494535 | 933 | } |
dd17c8f7 | 934 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
52494535 | 935 | completed = completed_end - completed; |
a241ec65 PM |
936 | if (completed > RCU_TORTURE_PIPE_LEN) { |
937 | /* Should not happen, but... */ | |
938 | completed = RCU_TORTURE_PIPE_LEN; | |
939 | } | |
dd17c8f7 | 940 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 941 | preempt_enable(); |
72e9bb54 | 942 | cur_ops->readunlock(idx); |
a241ec65 | 943 | schedule(); |
628edaa5 | 944 | stutter_wait("rcu_torture_reader"); |
36970bb9 | 945 | } while (!torture_must_stop()); |
0acc512c | 946 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 947 | del_timer_sync(&t); |
7fafaac5 | 948 | torture_kthread_stopping("rcu_torture_reader"); |
a241ec65 PM |
949 | return 0; |
950 | } | |
951 | ||
952 | /* | |
953 | * Create an RCU-torture statistics message in the specified buffer. | |
954 | */ | |
d1008950 | 955 | static void |
a241ec65 PM |
956 | rcu_torture_printk(char *page) |
957 | { | |
a241ec65 PM |
958 | int cpu; |
959 | int i; | |
960 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
961 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
ad0dc7f9 | 962 | static unsigned long rtcv_snap = ULONG_MAX; |
a241ec65 | 963 | |
0a945022 | 964 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
965 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
966 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
967 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
968 | } | |
969 | } | |
970 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
971 | if (pipesummary[i] != 0) | |
972 | break; | |
973 | } | |
d1008950 CG |
974 | page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG); |
975 | page += sprintf(page, | |
5cf05ad7 | 976 | "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", |
a241ec65 PM |
977 | rcu_torture_current, |
978 | rcu_torture_current_version, | |
979 | list_empty(&rcu_torture_freelist), | |
980 | atomic_read(&n_rcu_torture_alloc), | |
981 | atomic_read(&n_rcu_torture_alloc_fail), | |
5cf05ad7 | 982 | atomic_read(&n_rcu_torture_free)); |
d1008950 | 983 | page += sprintf(page, "rtmbe: %d rtbke: %ld rtbre: %ld ", |
0729fbf3 | 984 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e | 985 | n_rcu_torture_boost_ktrerror, |
5cf05ad7 | 986 | n_rcu_torture_boost_rterror); |
d1008950 | 987 | page += sprintf(page, "rtbf: %ld rtb: %ld nt: %ld ", |
8e8be45e PM |
988 | n_rcu_torture_boost_failure, |
989 | n_rcu_torture_boosts, | |
5cf05ad7 | 990 | n_rcu_torture_timers); |
2e9e8081 | 991 | page = torture_onoff_stats(page); |
d1008950 | 992 | page += sprintf(page, "barrier: %ld/%ld:%ld", |
fae4b54f PM |
993 | n_barrier_successes, |
994 | n_barrier_attempts, | |
995 | n_rcu_torture_barrier_error); | |
d1008950 | 996 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); |
8e8be45e | 997 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
fae4b54f | 998 | n_rcu_torture_barrier_error != 0 || |
8e8be45e PM |
999 | n_rcu_torture_boost_ktrerror != 0 || |
1000 | n_rcu_torture_boost_rterror != 0 || | |
fae4b54f PM |
1001 | n_rcu_torture_boost_failure != 0 || |
1002 | i > 1) { | |
d1008950 | 1003 | page += sprintf(page, "!!! "); |
996417d2 | 1004 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 1005 | WARN_ON_ONCE(1); |
996417d2 | 1006 | } |
d1008950 | 1007 | page += sprintf(page, "Reader Pipe: "); |
a241ec65 | 1008 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
d1008950 CG |
1009 | page += sprintf(page, " %ld", pipesummary[i]); |
1010 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); | |
1011 | page += sprintf(page, "Reader Batch: "); | |
72e9bb54 | 1012 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
d1008950 CG |
1013 | page += sprintf(page, " %ld", batchsummary[i]); |
1014 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); | |
1015 | page += sprintf(page, "Free-Block Circulation: "); | |
a241ec65 | 1016 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
d1008950 | 1017 | page += sprintf(page, " %d", |
a241ec65 PM |
1018 | atomic_read(&rcu_torture_wcount[i])); |
1019 | } | |
d1008950 | 1020 | page += sprintf(page, "\n"); |
c8e5b163 | 1021 | if (cur_ops->stats) |
d1008950 | 1022 | cur_ops->stats(page); |
ad0dc7f9 PM |
1023 | if (rtcv_snap == rcu_torture_current_version && |
1024 | rcu_torture_current != NULL) { | |
1025 | int __maybe_unused flags; | |
1026 | unsigned long __maybe_unused gpnum; | |
1027 | unsigned long __maybe_unused completed; | |
1028 | ||
1029 | rcutorture_get_gp_data(cur_ops->ttype, | |
1030 | &flags, &gpnum, &completed); | |
1031 | page += sprintf(page, | |
1032 | "??? Writer stall state %d g%lu c%lu f%#x\n", | |
1033 | rcu_torture_writer_state, | |
1034 | gpnum, completed, flags); | |
1035 | } | |
1036 | rtcv_snap = rcu_torture_current_version; | |
a241ec65 PM |
1037 | } |
1038 | ||
1039 | /* | |
1040 | * Print torture statistics. Caller must ensure that there is only | |
1041 | * one call to this function at a given time!!! This is normally | |
1042 | * accomplished by relying on the module system to only have one copy | |
1043 | * of the module loaded, and then by giving the rcu_torture_stats | |
1044 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1045 | * thread is not running). | |
1046 | */ | |
1047 | static void | |
1048 | rcu_torture_stats_print(void) | |
1049 | { | |
d1008950 CG |
1050 | int size = nr_cpu_ids * 200 + 8192; |
1051 | char *buf; | |
a241ec65 | 1052 | |
d1008950 CG |
1053 | buf = kmalloc(size, GFP_KERNEL); |
1054 | if (!buf) { | |
1055 | pr_err("rcu-torture: Out of memory, need: %d", size); | |
1056 | return; | |
1057 | } | |
1058 | rcu_torture_printk(buf); | |
1059 | pr_alert("%s", buf); | |
1060 | kfree(buf); | |
a241ec65 PM |
1061 | } |
1062 | ||
1063 | /* | |
1064 | * Periodically prints torture statistics, if periodic statistics printing | |
1065 | * was specified via the stat_interval module parameter. | |
a241ec65 PM |
1066 | */ |
1067 | static int | |
1068 | rcu_torture_stats(void *arg) | |
1069 | { | |
5ccf60f2 | 1070 | VERBOSE_TOROUT_STRING("rcu_torture_stats task started"); |
a241ec65 PM |
1071 | do { |
1072 | schedule_timeout_interruptible(stat_interval * HZ); | |
1073 | rcu_torture_stats_print(); | |
f67a3356 | 1074 | torture_shutdown_absorb("rcu_torture_stats"); |
36970bb9 | 1075 | } while (!torture_must_stop()); |
7fafaac5 | 1076 | torture_kthread_stopping("rcu_torture_stats"); |
d120f65f PM |
1077 | return 0; |
1078 | } | |
1079 | ||
95c38322 | 1080 | static inline void |
e66c33d5 | 1081 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) |
95c38322 | 1082 | { |
2caa1e44 PM |
1083 | pr_alert("%s" TORTURE_FLAG |
1084 | "--- %s: nreaders=%d nfakewriters=%d " | |
1085 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " | |
1086 | "shuffle_interval=%d stutter=%d irqreader=%d " | |
1087 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " | |
1088 | "test_boost=%d/%d test_boost_interval=%d " | |
1089 | "test_boost_duration=%d shutdown_secs=%d " | |
67afeed2 PM |
1090 | "stall_cpu=%d stall_cpu_holdoff=%d " |
1091 | "n_barrier_cbs=%d " | |
2caa1e44 PM |
1092 | "onoff_interval=%d onoff_holdoff=%d\n", |
1093 | torture_type, tag, nrealreaders, nfakewriters, | |
1094 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, | |
1095 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, | |
1096 | test_boost, cur_ops->can_boost, | |
1097 | test_boost_interval, test_boost_duration, shutdown_secs, | |
67afeed2 PM |
1098 | stall_cpu, stall_cpu_holdoff, |
1099 | n_barrier_cbs, | |
2caa1e44 | 1100 | onoff_interval, onoff_holdoff); |
95c38322 PM |
1101 | } |
1102 | ||
8e8be45e PM |
1103 | static void rcutorture_booster_cleanup(int cpu) |
1104 | { | |
1105 | struct task_struct *t; | |
1106 | ||
1107 | if (boost_tasks[cpu] == NULL) | |
1108 | return; | |
1109 | mutex_lock(&boost_mutex); | |
8e8be45e PM |
1110 | t = boost_tasks[cpu]; |
1111 | boost_tasks[cpu] = NULL; | |
1112 | mutex_unlock(&boost_mutex); | |
1113 | ||
1114 | /* This must be outside of the mutex, otherwise deadlock! */ | |
9c029b86 | 1115 | torture_stop_kthread(rcu_torture_boost, t); |
8e8be45e PM |
1116 | } |
1117 | ||
1118 | static int rcutorture_booster_init(int cpu) | |
1119 | { | |
1120 | int retval; | |
1121 | ||
1122 | if (boost_tasks[cpu] != NULL) | |
1123 | return 0; /* Already created, nothing more to do. */ | |
1124 | ||
1125 | /* Don't allow time recalculation while creating a new task. */ | |
1126 | mutex_lock(&boost_mutex); | |
5ccf60f2 | 1127 | VERBOSE_TOROUT_STRING("Creating rcu_torture_boost task"); |
1f288094 ED |
1128 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1129 | cpu_to_node(cpu), | |
1130 | "rcu_torture_boost"); | |
8e8be45e PM |
1131 | if (IS_ERR(boost_tasks[cpu])) { |
1132 | retval = PTR_ERR(boost_tasks[cpu]); | |
5ccf60f2 | 1133 | VERBOSE_TOROUT_STRING("rcu_torture_boost task create failed"); |
8e8be45e PM |
1134 | n_rcu_torture_boost_ktrerror++; |
1135 | boost_tasks[cpu] = NULL; | |
1136 | mutex_unlock(&boost_mutex); | |
1137 | return retval; | |
1138 | } | |
1139 | kthread_bind(boost_tasks[cpu], cpu); | |
1140 | wake_up_process(boost_tasks[cpu]); | |
1141 | mutex_unlock(&boost_mutex); | |
1142 | return 0; | |
1143 | } | |
1144 | ||
c13f3757 PM |
1145 | /* |
1146 | * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then | |
1147 | * induces a CPU stall for the time specified by stall_cpu. | |
1148 | */ | |
49fb4c62 | 1149 | static int rcu_torture_stall(void *args) |
c13f3757 PM |
1150 | { |
1151 | unsigned long stop_at; | |
1152 | ||
5ccf60f2 | 1153 | VERBOSE_TOROUT_STRING("rcu_torture_stall task started"); |
c13f3757 | 1154 | if (stall_cpu_holdoff > 0) { |
5ccf60f2 | 1155 | VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff"); |
c13f3757 | 1156 | schedule_timeout_interruptible(stall_cpu_holdoff * HZ); |
5ccf60f2 | 1157 | VERBOSE_TOROUT_STRING("rcu_torture_stall end holdoff"); |
c13f3757 PM |
1158 | } |
1159 | if (!kthread_should_stop()) { | |
1160 | stop_at = get_seconds() + stall_cpu; | |
1161 | /* RCU CPU stall is expected behavior in following code. */ | |
2caa1e44 | 1162 | pr_alert("rcu_torture_stall start.\n"); |
c13f3757 PM |
1163 | rcu_read_lock(); |
1164 | preempt_disable(); | |
1165 | while (ULONG_CMP_LT(get_seconds(), stop_at)) | |
1166 | continue; /* Induce RCU CPU stall warning. */ | |
1167 | preempt_enable(); | |
1168 | rcu_read_unlock(); | |
2caa1e44 | 1169 | pr_alert("rcu_torture_stall end.\n"); |
c13f3757 | 1170 | } |
f67a3356 | 1171 | torture_shutdown_absorb("rcu_torture_stall"); |
c13f3757 PM |
1172 | while (!kthread_should_stop()) |
1173 | schedule_timeout_interruptible(10 * HZ); | |
1174 | return 0; | |
1175 | } | |
1176 | ||
1177 | /* Spawn CPU-stall kthread, if stall_cpu specified. */ | |
1178 | static int __init rcu_torture_stall_init(void) | |
1179 | { | |
c13f3757 PM |
1180 | if (stall_cpu <= 0) |
1181 | return 0; | |
47cf29b9 | 1182 | return torture_create_kthread(rcu_torture_stall, NULL, stall_task); |
c13f3757 PM |
1183 | } |
1184 | ||
fae4b54f | 1185 | /* Callback function for RCU barrier testing. */ |
b3b8a4d4 | 1186 | static void rcu_torture_barrier_cbf(struct rcu_head *rcu) |
fae4b54f PM |
1187 | { |
1188 | atomic_inc(&barrier_cbs_invoked); | |
1189 | } | |
1190 | ||
1191 | /* kthread function to register callbacks used to test RCU barriers. */ | |
1192 | static int rcu_torture_barrier_cbs(void *arg) | |
1193 | { | |
1194 | long myid = (long)arg; | |
c6ebcbb6 | 1195 | bool lastphase = 0; |
78e4bc34 | 1196 | bool newphase; |
fae4b54f PM |
1197 | struct rcu_head rcu; |
1198 | ||
1199 | init_rcu_head_on_stack(&rcu); | |
5ccf60f2 | 1200 | VERBOSE_TOROUT_STRING("rcu_torture_barrier_cbs task started"); |
d277d868 | 1201 | set_user_nice(current, MAX_NICE); |
fae4b54f PM |
1202 | do { |
1203 | wait_event(barrier_cbs_wq[myid], | |
78e4bc34 PM |
1204 | (newphase = |
1205 | ACCESS_ONCE(barrier_phase)) != lastphase || | |
36970bb9 | 1206 | torture_must_stop()); |
78e4bc34 | 1207 | lastphase = newphase; |
c6ebcbb6 | 1208 | smp_mb(); /* ensure barrier_phase load before ->call(). */ |
36970bb9 | 1209 | if (torture_must_stop()) |
fae4b54f PM |
1210 | break; |
1211 | cur_ops->call(&rcu, rcu_torture_barrier_cbf); | |
1212 | if (atomic_dec_and_test(&barrier_cbs_count)) | |
1213 | wake_up(&barrier_wq); | |
36970bb9 | 1214 | } while (!torture_must_stop()); |
fae4b54f PM |
1215 | cur_ops->cb_barrier(); |
1216 | destroy_rcu_head_on_stack(&rcu); | |
7fafaac5 | 1217 | torture_kthread_stopping("rcu_torture_barrier_cbs"); |
fae4b54f PM |
1218 | return 0; |
1219 | } | |
1220 | ||
1221 | /* kthread function to drive and coordinate RCU barrier testing. */ | |
1222 | static int rcu_torture_barrier(void *arg) | |
1223 | { | |
1224 | int i; | |
1225 | ||
5ccf60f2 | 1226 | VERBOSE_TOROUT_STRING("rcu_torture_barrier task starting"); |
fae4b54f PM |
1227 | do { |
1228 | atomic_set(&barrier_cbs_invoked, 0); | |
1229 | atomic_set(&barrier_cbs_count, n_barrier_cbs); | |
c6ebcbb6 PM |
1230 | smp_mb(); /* Ensure barrier_phase after prior assignments. */ |
1231 | barrier_phase = !barrier_phase; | |
fae4b54f PM |
1232 | for (i = 0; i < n_barrier_cbs; i++) |
1233 | wake_up(&barrier_cbs_wq[i]); | |
1234 | wait_event(barrier_wq, | |
1235 | atomic_read(&barrier_cbs_count) == 0 || | |
36970bb9 PM |
1236 | torture_must_stop()); |
1237 | if (torture_must_stop()) | |
fae4b54f PM |
1238 | break; |
1239 | n_barrier_attempts++; | |
78e4bc34 | 1240 | cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */ |
fae4b54f PM |
1241 | if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { |
1242 | n_rcu_torture_barrier_error++; | |
1243 | WARN_ON_ONCE(1); | |
1244 | } | |
1245 | n_barrier_successes++; | |
1246 | schedule_timeout_interruptible(HZ / 10); | |
36970bb9 | 1247 | } while (!torture_must_stop()); |
7fafaac5 | 1248 | torture_kthread_stopping("rcu_torture_barrier"); |
fae4b54f PM |
1249 | return 0; |
1250 | } | |
1251 | ||
1252 | /* Initialize RCU barrier testing. */ | |
1253 | static int rcu_torture_barrier_init(void) | |
1254 | { | |
1255 | int i; | |
1256 | int ret; | |
1257 | ||
1258 | if (n_barrier_cbs == 0) | |
1259 | return 0; | |
1260 | if (cur_ops->call == NULL || cur_ops->cb_barrier == NULL) { | |
2caa1e44 PM |
1261 | pr_alert("%s" TORTURE_FLAG |
1262 | " Call or barrier ops missing for %s,\n", | |
1263 | torture_type, cur_ops->name); | |
1264 | pr_alert("%s" TORTURE_FLAG | |
1265 | " RCU barrier testing omitted from run.\n", | |
1266 | torture_type); | |
fae4b54f PM |
1267 | return 0; |
1268 | } | |
1269 | atomic_set(&barrier_cbs_count, 0); | |
1270 | atomic_set(&barrier_cbs_invoked, 0); | |
1271 | barrier_cbs_tasks = | |
1272 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_tasks[0]), | |
1273 | GFP_KERNEL); | |
1274 | barrier_cbs_wq = | |
1275 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_wq[0]), | |
1276 | GFP_KERNEL); | |
de5e6437 | 1277 | if (barrier_cbs_tasks == NULL || !barrier_cbs_wq) |
fae4b54f PM |
1278 | return -ENOMEM; |
1279 | for (i = 0; i < n_barrier_cbs; i++) { | |
1280 | init_waitqueue_head(&barrier_cbs_wq[i]); | |
47cf29b9 PM |
1281 | ret = torture_create_kthread(rcu_torture_barrier_cbs, |
1282 | (void *)(long)i, | |
1283 | barrier_cbs_tasks[i]); | |
1284 | if (ret) | |
fae4b54f | 1285 | return ret; |
fae4b54f | 1286 | } |
47cf29b9 | 1287 | return torture_create_kthread(rcu_torture_barrier, NULL, barrier_task); |
fae4b54f PM |
1288 | } |
1289 | ||
1290 | /* Clean up after RCU barrier testing. */ | |
1291 | static void rcu_torture_barrier_cleanup(void) | |
1292 | { | |
1293 | int i; | |
1294 | ||
9c029b86 | 1295 | torture_stop_kthread(rcu_torture_barrier, barrier_task); |
fae4b54f | 1296 | if (barrier_cbs_tasks != NULL) { |
9c029b86 PM |
1297 | for (i = 0; i < n_barrier_cbs; i++) |
1298 | torture_stop_kthread(rcu_torture_barrier_cbs, | |
1299 | barrier_cbs_tasks[i]); | |
fae4b54f PM |
1300 | kfree(barrier_cbs_tasks); |
1301 | barrier_cbs_tasks = NULL; | |
1302 | } | |
1303 | if (barrier_cbs_wq != NULL) { | |
1304 | kfree(barrier_cbs_wq); | |
1305 | barrier_cbs_wq = NULL; | |
1306 | } | |
1307 | } | |
1308 | ||
8e8be45e PM |
1309 | static int rcutorture_cpu_notify(struct notifier_block *self, |
1310 | unsigned long action, void *hcpu) | |
1311 | { | |
1312 | long cpu = (long)hcpu; | |
1313 | ||
1314 | switch (action) { | |
1315 | case CPU_ONLINE: | |
1316 | case CPU_DOWN_FAILED: | |
1317 | (void)rcutorture_booster_init(cpu); | |
1318 | break; | |
1319 | case CPU_DOWN_PREPARE: | |
1320 | rcutorture_booster_cleanup(cpu); | |
1321 | break; | |
1322 | default: | |
1323 | break; | |
1324 | } | |
1325 | return NOTIFY_OK; | |
1326 | } | |
1327 | ||
1328 | static struct notifier_block rcutorture_cpu_nb = { | |
1329 | .notifier_call = rcutorture_cpu_notify, | |
1330 | }; | |
1331 | ||
a241ec65 PM |
1332 | static void |
1333 | rcu_torture_cleanup(void) | |
1334 | { | |
1335 | int i; | |
1336 | ||
4a298656 | 1337 | rcutorture_record_test_transition(); |
cc47ae08 | 1338 | if (torture_cleanup()) { |
343e9099 PM |
1339 | if (cur_ops->cb_barrier != NULL) |
1340 | cur_ops->cb_barrier(); | |
1341 | return; | |
1342 | } | |
d84f5203 | 1343 | |
fae4b54f | 1344 | rcu_torture_barrier_cleanup(); |
9c029b86 | 1345 | torture_stop_kthread(rcu_torture_stall, stall_task); |
9c029b86 | 1346 | torture_stop_kthread(rcu_torture_writer, writer_task); |
a241ec65 | 1347 | |
c8e5b163 | 1348 | if (reader_tasks) { |
9c029b86 PM |
1349 | for (i = 0; i < nrealreaders; i++) |
1350 | torture_stop_kthread(rcu_torture_reader, | |
1351 | reader_tasks[i]); | |
a241ec65 | 1352 | kfree(reader_tasks); |
a241ec65 PM |
1353 | } |
1354 | rcu_torture_current = NULL; | |
1355 | ||
c8e5b163 | 1356 | if (fakewriter_tasks) { |
b772e1dd | 1357 | for (i = 0; i < nfakewriters; i++) { |
9c029b86 PM |
1358 | torture_stop_kthread(rcu_torture_fakewriter, |
1359 | fakewriter_tasks[i]); | |
b772e1dd JT |
1360 | } |
1361 | kfree(fakewriter_tasks); | |
1362 | fakewriter_tasks = NULL; | |
1363 | } | |
1364 | ||
9c029b86 PM |
1365 | torture_stop_kthread(rcu_torture_stats, stats_task); |
1366 | torture_stop_kthread(rcu_torture_fqs, fqs_task); | |
8e8be45e PM |
1367 | if ((test_boost == 1 && cur_ops->can_boost) || |
1368 | test_boost == 2) { | |
1369 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1370 | for_each_possible_cpu(i) | |
1371 | rcutorture_booster_cleanup(i); | |
1372 | } | |
bf66f18e | 1373 | |
a241ec65 | 1374 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1375 | |
1376 | if (cur_ops->cb_barrier != NULL) | |
1377 | cur_ops->cb_barrier(); | |
a241ec65 | 1378 | |
a241ec65 | 1379 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1380 | |
fae4b54f | 1381 | if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error) |
8e8be45e | 1382 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
2e9e8081 | 1383 | else if (torture_onoff_failures()) |
091541bb PM |
1384 | rcu_torture_print_module_parms(cur_ops, |
1385 | "End of test: RCU_HOTPLUG"); | |
95c38322 | 1386 | else |
8e8be45e | 1387 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1388 | } |
1389 | ||
d2818df1 PM |
1390 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD |
1391 | static void rcu_torture_leak_cb(struct rcu_head *rhp) | |
1392 | { | |
1393 | } | |
1394 | ||
1395 | static void rcu_torture_err_cb(struct rcu_head *rhp) | |
1396 | { | |
1397 | /* | |
1398 | * This -might- happen due to race conditions, but is unlikely. | |
1399 | * The scenario that leads to this happening is that the | |
1400 | * first of the pair of duplicate callbacks is queued, | |
1401 | * someone else starts a grace period that includes that | |
1402 | * callback, then the second of the pair must wait for the | |
1403 | * next grace period. Unlikely, but can happen. If it | |
1404 | * does happen, the debug-objects subsystem won't have splatted. | |
1405 | */ | |
1406 | pr_alert("rcutorture: duplicated callback was invoked.\n"); | |
1407 | } | |
1408 | #endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1409 | ||
1410 | /* | |
1411 | * Verify that double-free causes debug-objects to complain, but only | |
1412 | * if CONFIG_DEBUG_OBJECTS_RCU_HEAD=y. Otherwise, say that the test | |
1413 | * cannot be carried out. | |
1414 | */ | |
1415 | static void rcu_test_debug_objects(void) | |
1416 | { | |
1417 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD | |
1418 | struct rcu_head rh1; | |
1419 | struct rcu_head rh2; | |
1420 | ||
1421 | init_rcu_head_on_stack(&rh1); | |
1422 | init_rcu_head_on_stack(&rh2); | |
1423 | pr_alert("rcutorture: WARN: Duplicate call_rcu() test starting.\n"); | |
1424 | ||
1425 | /* Try to queue the rh2 pair of callbacks for the same grace period. */ | |
1426 | preempt_disable(); /* Prevent preemption from interrupting test. */ | |
1427 | rcu_read_lock(); /* Make it impossible to finish a grace period. */ | |
1428 | call_rcu(&rh1, rcu_torture_leak_cb); /* Start grace period. */ | |
1429 | local_irq_disable(); /* Make it harder to start a new grace period. */ | |
1430 | call_rcu(&rh2, rcu_torture_leak_cb); | |
1431 | call_rcu(&rh2, rcu_torture_err_cb); /* Duplicate callback. */ | |
1432 | local_irq_enable(); | |
1433 | rcu_read_unlock(); | |
1434 | preempt_enable(); | |
1435 | ||
1436 | /* Wait for them all to get done so we can safely return. */ | |
1437 | rcu_barrier(); | |
1438 | pr_alert("rcutorture: WARN: Duplicate call_rcu() test complete.\n"); | |
1439 | destroy_rcu_head_on_stack(&rh1); | |
1440 | destroy_rcu_head_on_stack(&rh2); | |
1441 | #else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1442 | pr_alert("rcutorture: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n"); | |
1443 | #endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1444 | } | |
1445 | ||
6f8bc500 | 1446 | static int __init |
a241ec65 PM |
1447 | rcu_torture_init(void) |
1448 | { | |
1449 | int i; | |
1450 | int cpu; | |
1451 | int firsterr = 0; | |
2ec1f2d9 | 1452 | static struct rcu_torture_ops *torture_ops[] = { |
ff20e251 | 1453 | &rcu_ops, &rcu_bh_ops, &rcu_busted_ops, &srcu_ops, &sched_ops, |
2ec1f2d9 | 1454 | }; |
a241ec65 | 1455 | |
628edaa5 | 1456 | torture_init_begin(torture_type, verbose, &rcutorture_runnable); |
343e9099 | 1457 | |
a241ec65 | 1458 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1459 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1460 | cur_ops = torture_ops[i]; |
ade5fb81 | 1461 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1462 | break; |
72e9bb54 | 1463 | } |
ade5fb81 | 1464 | if (i == ARRAY_SIZE(torture_ops)) { |
2caa1e44 PM |
1465 | pr_alert("rcu-torture: invalid torture type: \"%s\"\n", |
1466 | torture_type); | |
1467 | pr_alert("rcu-torture types:"); | |
cf886c44 | 1468 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) |
2caa1e44 PM |
1469 | pr_alert(" %s", torture_ops[i]->name); |
1470 | pr_alert("\n"); | |
b5daa8f3 | 1471 | torture_init_end(); |
a71fca58 | 1472 | return -EINVAL; |
72e9bb54 | 1473 | } |
bf66f18e | 1474 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
2caa1e44 | 1475 | pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); |
bf66f18e PM |
1476 | fqs_duration = 0; |
1477 | } | |
c8e5b163 | 1478 | if (cur_ops->init) |
72e9bb54 PM |
1479 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1480 | ||
a241ec65 PM |
1481 | if (nreaders >= 0) |
1482 | nrealreaders = nreaders; | |
1483 | else | |
1484 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1485 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
a241ec65 PM |
1486 | |
1487 | /* Set up the freelist. */ | |
1488 | ||
1489 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1490 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1491 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1492 | list_add_tail(&rcu_tortures[i].rtort_free, |
1493 | &rcu_torture_freelist); | |
1494 | } | |
1495 | ||
1496 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1497 | ||
1498 | rcu_torture_current = NULL; | |
1499 | rcu_torture_current_version = 0; | |
1500 | atomic_set(&n_rcu_torture_alloc, 0); | |
1501 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1502 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1503 | atomic_set(&n_rcu_torture_mberror, 0); |
1504 | atomic_set(&n_rcu_torture_error, 0); | |
fae4b54f | 1505 | n_rcu_torture_barrier_error = 0; |
8e8be45e PM |
1506 | n_rcu_torture_boost_ktrerror = 0; |
1507 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
1508 | n_rcu_torture_boost_failure = 0; |
1509 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1510 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1511 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1512 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1513 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1514 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1515 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1516 | } | |
1517 | } | |
1518 | ||
1519 | /* Start up the kthreads. */ | |
1520 | ||
47cf29b9 PM |
1521 | firsterr = torture_create_kthread(rcu_torture_writer, NULL, |
1522 | writer_task); | |
1523 | if (firsterr) | |
a241ec65 | 1524 | goto unwind; |
b772e1dd | 1525 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1526 | GFP_KERNEL); |
b772e1dd | 1527 | if (fakewriter_tasks == NULL) { |
5ccf60f2 | 1528 | VERBOSE_TOROUT_ERRSTRING("out of memory"); |
b772e1dd JT |
1529 | firsterr = -ENOMEM; |
1530 | goto unwind; | |
1531 | } | |
1532 | for (i = 0; i < nfakewriters; i++) { | |
47cf29b9 PM |
1533 | firsterr = torture_create_kthread(rcu_torture_fakewriter, |
1534 | NULL, fakewriter_tasks[i]); | |
1535 | if (firsterr) | |
b772e1dd | 1536 | goto unwind; |
b772e1dd | 1537 | } |
2860aaba | 1538 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1539 | GFP_KERNEL); |
1540 | if (reader_tasks == NULL) { | |
5ccf60f2 | 1541 | VERBOSE_TOROUT_ERRSTRING("out of memory"); |
a241ec65 PM |
1542 | firsterr = -ENOMEM; |
1543 | goto unwind; | |
1544 | } | |
1545 | for (i = 0; i < nrealreaders; i++) { | |
47cf29b9 PM |
1546 | firsterr = torture_create_kthread(rcu_torture_reader, NULL, |
1547 | reader_tasks[i]); | |
1548 | if (firsterr) | |
a241ec65 | 1549 | goto unwind; |
a241ec65 PM |
1550 | } |
1551 | if (stat_interval > 0) { | |
47cf29b9 PM |
1552 | firsterr = torture_create_kthread(rcu_torture_stats, NULL, |
1553 | stats_task); | |
1554 | if (firsterr) | |
a241ec65 | 1555 | goto unwind; |
a241ec65 | 1556 | } |
d84f5203 | 1557 | if (test_no_idle_hz) { |
3808dc9f PM |
1558 | firsterr = torture_shuffle_init(shuffle_interval * HZ); |
1559 | if (firsterr) | |
d84f5203 | 1560 | goto unwind; |
d84f5203 | 1561 | } |
d120f65f PM |
1562 | if (stutter < 0) |
1563 | stutter = 0; | |
1564 | if (stutter) { | |
628edaa5 PM |
1565 | firsterr = torture_stutter_init(stutter * HZ); |
1566 | if (firsterr) | |
d120f65f | 1567 | goto unwind; |
d120f65f | 1568 | } |
bf66f18e PM |
1569 | if (fqs_duration < 0) |
1570 | fqs_duration = 0; | |
1571 | if (fqs_duration) { | |
628edaa5 | 1572 | /* Create the fqs thread */ |
47cf29b9 PM |
1573 | torture_create_kthread(rcu_torture_fqs, NULL, fqs_task); |
1574 | if (firsterr) | |
bf66f18e | 1575 | goto unwind; |
bf66f18e | 1576 | } |
8e8be45e PM |
1577 | if (test_boost_interval < 1) |
1578 | test_boost_interval = 1; | |
1579 | if (test_boost_duration < 2) | |
1580 | test_boost_duration = 2; | |
1581 | if ((test_boost == 1 && cur_ops->can_boost) || | |
1582 | test_boost == 2) { | |
8e8be45e PM |
1583 | |
1584 | boost_starttime = jiffies + test_boost_interval * HZ; | |
1585 | register_cpu_notifier(&rcutorture_cpu_nb); | |
1586 | for_each_possible_cpu(i) { | |
1587 | if (cpu_is_offline(i)) | |
1588 | continue; /* Heuristic: CPU can go offline. */ | |
01025ebc PM |
1589 | firsterr = rcutorture_booster_init(i); |
1590 | if (firsterr) | |
8e8be45e | 1591 | goto unwind; |
8e8be45e PM |
1592 | } |
1593 | } | |
01025ebc PM |
1594 | firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup); |
1595 | if (firsterr) | |
37e377d2 | 1596 | goto unwind; |
01025ebc PM |
1597 | firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval * HZ); |
1598 | if (firsterr) | |
37e377d2 | 1599 | goto unwind; |
01025ebc PM |
1600 | firsterr = rcu_torture_stall_init(); |
1601 | if (firsterr) | |
37e377d2 | 1602 | goto unwind; |
01025ebc PM |
1603 | firsterr = rcu_torture_barrier_init(); |
1604 | if (firsterr) | |
fae4b54f | 1605 | goto unwind; |
d2818df1 PM |
1606 | if (object_debug) |
1607 | rcu_test_debug_objects(); | |
4a298656 | 1608 | rcutorture_record_test_transition(); |
b5daa8f3 | 1609 | torture_init_end(); |
a241ec65 PM |
1610 | return 0; |
1611 | ||
1612 | unwind: | |
b5daa8f3 | 1613 | torture_init_end(); |
a241ec65 PM |
1614 | rcu_torture_cleanup(); |
1615 | return firsterr; | |
1616 | } | |
1617 | ||
1618 | module_init(rcu_torture_init); | |
1619 | module_exit(rcu_torture_cleanup); |