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a241ec65 | 1 | /* |
29766f1e | 2 | * Read-Copy Update module-based torture test facility |
a241ec65 PM |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
b772e1dd | 18 | * Copyright (C) IBM Corporation, 2005, 2006 |
a241ec65 PM |
19 | * |
20 | * Authors: Paul E. McKenney <paulmck@us.ibm.com> | |
a71fca58 | 21 | * Josh Triplett <josh@freedesktop.org> |
a241ec65 PM |
22 | * |
23 | * See also: Documentation/RCU/torture.txt | |
24 | */ | |
25 | #include <linux/types.h> | |
26 | #include <linux/kernel.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/kthread.h> | |
30 | #include <linux/err.h> | |
31 | #include <linux/spinlock.h> | |
32 | #include <linux/smp.h> | |
33 | #include <linux/rcupdate.h> | |
34 | #include <linux/interrupt.h> | |
35 | #include <linux/sched.h> | |
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 PM |
56 | MODULE_ALIAS("rcutorture"); |
57 | #ifdef MODULE_PARAM_PREFIX | |
58 | #undef MODULE_PARAM_PREFIX | |
59 | #endif | |
60 | #define MODULE_PARAM_PREFIX "rcutorture." | |
61 | ||
9e250225 PM |
62 | torture_param(int, fqs_duration, 0, |
63 | "Duration of fqs bursts (us), 0 to disable"); | |
64 | torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)"); | |
65 | torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)"); | |
66 | torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); | |
67 | torture_param(bool, gp_normal, false, | |
68 | "Use normal (non-expedited) GP wait primitives"); | |
69 | torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers"); | |
70 | torture_param(int, n_barrier_cbs, 0, | |
71 | "# of callbacks/kthreads for barrier testing"); | |
72 | torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads"); | |
73 | torture_param(int, nreaders, -1, "Number of RCU reader threads"); | |
74 | torture_param(int, object_debug, 0, | |
75 | "Enable debug-object double call_rcu() testing"); | |
76 | torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); | |
77 | torture_param(int, onoff_interval, 0, | |
78 | "Time between CPU hotplugs (s), 0=disable"); | |
79 | torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); | |
80 | torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); | |
81 | torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); | |
82 | torture_param(int, stall_cpu_holdoff, 10, | |
83 | "Time to wait before starting stall (s)."); | |
84 | torture_param(int, stat_interval, 60, | |
85 | "Number of seconds between stats printk()s"); | |
86 | torture_param(int, stutter, 5, "Number of seconds to run/halt test"); | |
87 | torture_param(int, test_boost, 1, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); | |
88 | torture_param(int, test_boost_duration, 4, | |
89 | "Duration of each boost test, seconds."); | |
90 | torture_param(int, test_boost_interval, 7, | |
91 | "Interval between boost tests, seconds."); | |
92 | torture_param(bool, test_no_idle_hz, true, | |
93 | "Test support for tickless idle CPUs"); | |
94 | torture_param(bool, verbose, false, "Enable verbose debugging printk()s"); | |
95 | ||
d10453e9 | 96 | static char *torture_type = "rcu"; |
d6ad6711 | 97 | module_param(torture_type, charp, 0444); |
d10453e9 | 98 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, ...)"); |
72e9bb54 PM |
99 | |
100 | #define TORTURE_FLAG "-torture:" | |
a241ec65 | 101 | #define PRINTK_STRING(s) \ |
2caa1e44 | 102 | do { pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 103 | #define VERBOSE_PRINTK_STRING(s) \ |
2caa1e44 | 104 | do { if (verbose) pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 105 | #define VERBOSE_PRINTK_ERRSTRING(s) \ |
2caa1e44 | 106 | do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) |
a241ec65 | 107 | |
a241ec65 PM |
108 | static int nrealreaders; |
109 | static struct task_struct *writer_task; | |
b772e1dd | 110 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
111 | static struct task_struct **reader_tasks; |
112 | static struct task_struct *stats_task; | |
d84f5203 | 113 | static struct task_struct *shuffler_task; |
d120f65f | 114 | static struct task_struct *stutter_task; |
bf66f18e | 115 | static struct task_struct *fqs_task; |
8e8be45e | 116 | static struct task_struct *boost_tasks[NR_CPUS]; |
d5f546d8 | 117 | static struct task_struct *shutdown_task; |
b58bdcca PM |
118 | #ifdef CONFIG_HOTPLUG_CPU |
119 | static struct task_struct *onoff_task; | |
120 | #endif /* #ifdef CONFIG_HOTPLUG_CPU */ | |
c13f3757 | 121 | static struct task_struct *stall_task; |
fae4b54f PM |
122 | static struct task_struct **barrier_cbs_tasks; |
123 | static struct task_struct *barrier_task; | |
a241ec65 PM |
124 | |
125 | #define RCU_TORTURE_PIPE_LEN 10 | |
126 | ||
127 | struct rcu_torture { | |
128 | struct rcu_head rtort_rcu; | |
129 | int rtort_pipe_count; | |
130 | struct list_head rtort_free; | |
996417d2 | 131 | int rtort_mbtest; |
a241ec65 PM |
132 | }; |
133 | ||
a241ec65 | 134 | static LIST_HEAD(rcu_torture_freelist); |
0ddea0ea | 135 | static struct rcu_torture __rcu *rcu_torture_current; |
4a298656 | 136 | static unsigned long rcu_torture_current_version; |
a241ec65 PM |
137 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
138 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
806274c0 PM |
139 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], |
140 | rcu_torture_count) = { 0 }; | |
141 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], | |
142 | rcu_torture_batch) = { 0 }; | |
a241ec65 | 143 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; |
b2896d2e PM |
144 | static atomic_t n_rcu_torture_alloc; |
145 | static atomic_t n_rcu_torture_alloc_fail; | |
146 | static atomic_t n_rcu_torture_free; | |
147 | static atomic_t n_rcu_torture_mberror; | |
148 | static atomic_t n_rcu_torture_error; | |
fae4b54f | 149 | static long n_rcu_torture_barrier_error; |
8e8be45e PM |
150 | static long n_rcu_torture_boost_ktrerror; |
151 | static long n_rcu_torture_boost_rterror; | |
8e8be45e PM |
152 | static long n_rcu_torture_boost_failure; |
153 | static long n_rcu_torture_boosts; | |
a71fca58 | 154 | static long n_rcu_torture_timers; |
b58bdcca PM |
155 | static long n_offline_attempts; |
156 | static long n_offline_successes; | |
13dbf914 PM |
157 | static unsigned long sum_offline; |
158 | static int min_offline = -1; | |
159 | static int max_offline; | |
b58bdcca PM |
160 | static long n_online_attempts; |
161 | static long n_online_successes; | |
13dbf914 PM |
162 | static unsigned long sum_online; |
163 | static int min_online = -1; | |
164 | static int max_online; | |
fae4b54f PM |
165 | static long n_barrier_attempts; |
166 | static long n_barrier_successes; | |
e3033736 | 167 | static struct list_head rcu_torture_removed; |
73d0a4b1 | 168 | static cpumask_var_t shuffle_tmp_mask; |
a241ec65 | 169 | |
a71fca58 | 170 | static int stutter_pause_test; |
d120f65f | 171 | |
31a72bce PM |
172 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
173 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
174 | #else | |
175 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
176 | #endif | |
177 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
bb3bf705 PM |
178 | module_param(rcutorture_runnable, int, 0444); |
179 | MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot"); | |
31a72bce | 180 | |
3acf4a9a | 181 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 182 | #define rcu_can_boost() 1 |
3acf4a9a | 183 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 184 | #define rcu_can_boost() 0 |
3acf4a9a | 185 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 186 | |
e4aa0da3 SR |
187 | #ifdef CONFIG_RCU_TRACE |
188 | static u64 notrace rcu_trace_clock_local(void) | |
189 | { | |
190 | u64 ts = trace_clock_local(); | |
191 | unsigned long __maybe_unused ts_rem = do_div(ts, NSEC_PER_USEC); | |
192 | return ts; | |
193 | } | |
194 | #else /* #ifdef CONFIG_RCU_TRACE */ | |
195 | static u64 notrace rcu_trace_clock_local(void) | |
196 | { | |
197 | return 0ULL; | |
198 | } | |
199 | #endif /* #else #ifdef CONFIG_RCU_TRACE */ | |
200 | ||
d5f546d8 | 201 | static unsigned long shutdown_time; /* jiffies to system shutdown. */ |
8e8be45e PM |
202 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
203 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
204 | /* and boost task create/destroy. */ | |
fae4b54f | 205 | static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */ |
c6ebcbb6 | 206 | static bool barrier_phase; /* Test phase. */ |
fae4b54f PM |
207 | static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */ |
208 | static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */ | |
209 | static DECLARE_WAIT_QUEUE_HEAD(barrier_wq); | |
8e8be45e | 210 | |
c9d557c1 PM |
211 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
212 | ||
213 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
214 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
215 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
216 | static int fullstop = FULLSTOP_RMMOD; | |
0ddea0ea PM |
217 | /* |
218 | * Protect fullstop transitions and spawning of kthreads. | |
219 | */ | |
220 | static DEFINE_MUTEX(fullstop_mutex); | |
343e9099 | 221 | |
d5f546d8 PM |
222 | /* Forward reference. */ |
223 | static void rcu_torture_cleanup(void); | |
224 | ||
343e9099 | 225 | /* |
c9d557c1 | 226 | * Detect and respond to a system shutdown. |
343e9099 PM |
227 | */ |
228 | static int | |
229 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
230 | unsigned long unused2, void *unused3) | |
231 | { | |
c59ab97e | 232 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 233 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 234 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 | 235 | else |
2caa1e44 | 236 | pr_warn(/* but going down anyway, so... */ |
c9d557c1 | 237 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); |
c59ab97e | 238 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
239 | return NOTIFY_DONE; |
240 | } | |
241 | ||
c9d557c1 PM |
242 | /* |
243 | * Absorb kthreads into a kernel function that won't return, so that | |
244 | * they won't ever access module text or data again. | |
245 | */ | |
e66c33d5 | 246 | static void rcutorture_shutdown_absorb(const char *title) |
c9d557c1 PM |
247 | { |
248 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
2caa1e44 | 249 | pr_notice( |
c9d557c1 PM |
250 | "rcutorture thread %s parking due to system shutdown\n", |
251 | title); | |
252 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
253 | } | |
254 | } | |
255 | ||
a241ec65 PM |
256 | /* |
257 | * Allocate an element from the rcu_tortures pool. | |
258 | */ | |
97a41e26 | 259 | static struct rcu_torture * |
a241ec65 PM |
260 | rcu_torture_alloc(void) |
261 | { | |
262 | struct list_head *p; | |
263 | ||
adac1665 | 264 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
265 | if (list_empty(&rcu_torture_freelist)) { |
266 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 267 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
268 | return NULL; |
269 | } | |
270 | atomic_inc(&n_rcu_torture_alloc); | |
271 | p = rcu_torture_freelist.next; | |
272 | list_del_init(p); | |
adac1665 | 273 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
274 | return container_of(p, struct rcu_torture, rtort_free); |
275 | } | |
276 | ||
277 | /* | |
278 | * Free an element to the rcu_tortures pool. | |
279 | */ | |
280 | static void | |
281 | rcu_torture_free(struct rcu_torture *p) | |
282 | { | |
283 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 284 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 285 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 286 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
287 | } |
288 | ||
d120f65f | 289 | static void |
e66c33d5 | 290 | rcu_stutter_wait(const char *title) |
d120f65f | 291 | { |
c9d557c1 | 292 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
293 | if (rcutorture_runnable) |
294 | schedule_timeout_interruptible(1); | |
295 | else | |
3ccf79f4 | 296 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 297 | rcutorture_shutdown_absorb(title); |
343e9099 | 298 | } |
d120f65f PM |
299 | } |
300 | ||
72e9bb54 PM |
301 | /* |
302 | * Operations vector for selecting different types of tests. | |
303 | */ | |
304 | ||
305 | struct rcu_torture_ops { | |
306 | void (*init)(void); | |
72e9bb54 | 307 | int (*readlock)(void); |
51b1130e | 308 | void (*read_delay)(struct torture_random_state *rrsp); |
72e9bb54 PM |
309 | void (*readunlock)(int idx); |
310 | int (*completed)(void); | |
0acc512c | 311 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 312 | void (*sync)(void); |
2ec1f2d9 | 313 | void (*exp_sync)(void); |
fae4b54f | 314 | void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); |
2326974d | 315 | void (*cb_barrier)(void); |
bf66f18e | 316 | void (*fqs)(void); |
d1008950 | 317 | void (*stats)(char *page); |
0acc512c | 318 | int irq_capable; |
8e8be45e | 319 | int can_boost; |
e66c33d5 | 320 | const char *name; |
72e9bb54 | 321 | }; |
a71fca58 PM |
322 | |
323 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
324 | |
325 | /* | |
326 | * Definitions for rcu torture testing. | |
327 | */ | |
328 | ||
a49a4af7 | 329 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
330 | { |
331 | rcu_read_lock(); | |
332 | return 0; | |
333 | } | |
334 | ||
51b1130e | 335 | static void rcu_read_delay(struct torture_random_state *rrsp) |
b2896d2e | 336 | { |
b8d57a76 JT |
337 | const unsigned long shortdelay_us = 200; |
338 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 339 | |
b8d57a76 JT |
340 | /* We want a short delay sometimes to make a reader delay the grace |
341 | * period, and we want a long delay occasionally to trigger | |
342 | * force_quiescent_state. */ | |
b2896d2e | 343 | |
51b1130e | 344 | if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
b8d57a76 | 345 | mdelay(longdelay_ms); |
51b1130e | 346 | if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) |
b8d57a76 | 347 | udelay(shortdelay_us); |
e546f485 | 348 | #ifdef CONFIG_PREEMPT |
51b1130e PM |
349 | if (!preempt_count() && |
350 | !(torture_random(rrsp) % (nrealreaders * 20000))) | |
e546f485 LJ |
351 | preempt_schedule(); /* No QS if preempt_disable() in effect */ |
352 | #endif | |
b2896d2e PM |
353 | } |
354 | ||
a49a4af7 | 355 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
356 | { |
357 | rcu_read_unlock(); | |
358 | } | |
359 | ||
360 | static int rcu_torture_completed(void) | |
361 | { | |
362 | return rcu_batches_completed(); | |
363 | } | |
364 | ||
365 | static void | |
366 | rcu_torture_cb(struct rcu_head *p) | |
367 | { | |
368 | int i; | |
369 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
370 | ||
c9d557c1 | 371 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
372 | /* Test is ending, just drop callbacks on the floor. */ |
373 | /* The next initialization will pick up the pieces. */ | |
374 | return; | |
375 | } | |
376 | i = rp->rtort_pipe_count; | |
377 | if (i > RCU_TORTURE_PIPE_LEN) | |
378 | i = RCU_TORTURE_PIPE_LEN; | |
379 | atomic_inc(&rcu_torture_wcount[i]); | |
380 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
381 | rp->rtort_mbtest = 0; | |
382 | rcu_torture_free(rp); | |
c701d5d9 | 383 | } else { |
0acc512c | 384 | cur_ops->deferred_free(rp); |
c701d5d9 | 385 | } |
72e9bb54 PM |
386 | } |
387 | ||
d9a3da06 PM |
388 | static int rcu_no_completed(void) |
389 | { | |
390 | return 0; | |
391 | } | |
392 | ||
72e9bb54 PM |
393 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
394 | { | |
395 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
396 | } | |
397 | ||
e3033736 JT |
398 | static void rcu_sync_torture_init(void) |
399 | { | |
400 | INIT_LIST_HEAD(&rcu_torture_removed); | |
401 | } | |
402 | ||
2ec1f2d9 | 403 | static struct rcu_torture_ops rcu_ops = { |
0acc512c | 404 | .init = rcu_sync_torture_init, |
0acc512c PM |
405 | .readlock = rcu_torture_read_lock, |
406 | .read_delay = rcu_read_delay, | |
407 | .readunlock = rcu_torture_read_unlock, | |
408 | .completed = rcu_torture_completed, | |
2ec1f2d9 | 409 | .deferred_free = rcu_torture_deferred_free, |
0acc512c | 410 | .sync = synchronize_rcu, |
2ec1f2d9 PM |
411 | .exp_sync = synchronize_rcu_expedited, |
412 | .call = call_rcu, | |
413 | .cb_barrier = rcu_barrier, | |
bf66f18e | 414 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
415 | .stats = NULL, |
416 | .irq_capable = 1, | |
8e8be45e | 417 | .can_boost = rcu_can_boost(), |
2ec1f2d9 | 418 | .name = "rcu" |
d9a3da06 PM |
419 | }; |
420 | ||
c32e0660 PM |
421 | /* |
422 | * Definitions for rcu_bh torture testing. | |
423 | */ | |
424 | ||
a49a4af7 | 425 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
426 | { |
427 | rcu_read_lock_bh(); | |
428 | return 0; | |
429 | } | |
430 | ||
a49a4af7 | 431 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
432 | { |
433 | rcu_read_unlock_bh(); | |
434 | } | |
435 | ||
436 | static int rcu_bh_torture_completed(void) | |
437 | { | |
438 | return rcu_batches_completed_bh(); | |
439 | } | |
440 | ||
441 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
442 | { | |
443 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
444 | } | |
445 | ||
446 | static struct rcu_torture_ops rcu_bh_ops = { | |
2ec1f2d9 | 447 | .init = rcu_sync_torture_init, |
0acc512c PM |
448 | .readlock = rcu_bh_torture_read_lock, |
449 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
450 | .readunlock = rcu_bh_torture_read_unlock, | |
451 | .completed = rcu_bh_torture_completed, | |
452 | .deferred_free = rcu_bh_torture_deferred_free, | |
bdf2a436 | 453 | .sync = synchronize_rcu_bh, |
2ec1f2d9 | 454 | .exp_sync = synchronize_rcu_bh_expedited, |
fae4b54f | 455 | .call = call_rcu_bh, |
0acc512c | 456 | .cb_barrier = rcu_barrier_bh, |
bf66f18e | 457 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
458 | .stats = NULL, |
459 | .irq_capable = 1, | |
460 | .name = "rcu_bh" | |
c32e0660 PM |
461 | }; |
462 | ||
b2896d2e PM |
463 | /* |
464 | * Definitions for srcu torture testing. | |
465 | */ | |
466 | ||
cda4dc81 | 467 | DEFINE_STATIC_SRCU(srcu_ctl); |
b2896d2e | 468 | |
012d3ca8 | 469 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
470 | { |
471 | return srcu_read_lock(&srcu_ctl); | |
472 | } | |
473 | ||
51b1130e | 474 | static void srcu_read_delay(struct torture_random_state *rrsp) |
b2896d2e PM |
475 | { |
476 | long delay; | |
477 | const long uspertick = 1000000 / HZ; | |
478 | const long longdelay = 10; | |
479 | ||
480 | /* We want there to be long-running readers, but not all the time. */ | |
481 | ||
51b1130e PM |
482 | delay = torture_random(rrsp) % |
483 | (nrealreaders * 2 * longdelay * uspertick); | |
b2896d2e PM |
484 | if (!delay) |
485 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
486 | else |
487 | rcu_read_delay(rrsp); | |
b2896d2e PM |
488 | } |
489 | ||
012d3ca8 | 490 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
491 | { |
492 | srcu_read_unlock(&srcu_ctl, idx); | |
493 | } | |
494 | ||
495 | static int srcu_torture_completed(void) | |
496 | { | |
497 | return srcu_batches_completed(&srcu_ctl); | |
498 | } | |
499 | ||
9059c940 LJ |
500 | static void srcu_torture_deferred_free(struct rcu_torture *rp) |
501 | { | |
502 | call_srcu(&srcu_ctl, &rp->rtort_rcu, rcu_torture_cb); | |
503 | } | |
504 | ||
b772e1dd JT |
505 | static void srcu_torture_synchronize(void) |
506 | { | |
507 | synchronize_srcu(&srcu_ctl); | |
508 | } | |
509 | ||
e3f8d378 PM |
510 | static void srcu_torture_call(struct rcu_head *head, |
511 | void (*func)(struct rcu_head *head)) | |
512 | { | |
513 | call_srcu(&srcu_ctl, head, func); | |
514 | } | |
515 | ||
516 | static void srcu_torture_barrier(void) | |
517 | { | |
518 | srcu_barrier(&srcu_ctl); | |
519 | } | |
520 | ||
d1008950 | 521 | static void srcu_torture_stats(char *page) |
b2896d2e | 522 | { |
b2896d2e PM |
523 | int cpu; |
524 | int idx = srcu_ctl.completed & 0x1; | |
525 | ||
d1008950 | 526 | page += sprintf(page, "%s%s per-CPU(idx=%d):", |
b2896d2e PM |
527 | torture_type, TORTURE_FLAG, idx); |
528 | for_each_possible_cpu(cpu) { | |
d1008950 | 529 | page += sprintf(page, " %d(%lu,%lu)", cpu, |
b2896d2e PM |
530 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], |
531 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
532 | } | |
d1008950 | 533 | sprintf(page, "\n"); |
b2896d2e PM |
534 | } |
535 | ||
2ec1f2d9 PM |
536 | static void srcu_torture_synchronize_expedited(void) |
537 | { | |
538 | synchronize_srcu_expedited(&srcu_ctl); | |
539 | } | |
540 | ||
b2896d2e | 541 | static struct rcu_torture_ops srcu_ops = { |
cda4dc81 | 542 | .init = rcu_sync_torture_init, |
0acc512c PM |
543 | .readlock = srcu_torture_read_lock, |
544 | .read_delay = srcu_read_delay, | |
545 | .readunlock = srcu_torture_read_unlock, | |
546 | .completed = srcu_torture_completed, | |
9059c940 | 547 | .deferred_free = srcu_torture_deferred_free, |
0acc512c | 548 | .sync = srcu_torture_synchronize, |
2ec1f2d9 | 549 | .exp_sync = srcu_torture_synchronize_expedited, |
e3f8d378 PM |
550 | .call = srcu_torture_call, |
551 | .cb_barrier = srcu_torture_barrier, | |
0acc512c PM |
552 | .stats = srcu_torture_stats, |
553 | .name = "srcu" | |
b2896d2e PM |
554 | }; |
555 | ||
4b6c2cca JT |
556 | /* |
557 | * Definitions for sched torture testing. | |
558 | */ | |
559 | ||
560 | static int sched_torture_read_lock(void) | |
561 | { | |
562 | preempt_disable(); | |
563 | return 0; | |
564 | } | |
565 | ||
566 | static void sched_torture_read_unlock(int idx) | |
567 | { | |
568 | preempt_enable(); | |
569 | } | |
570 | ||
2326974d PM |
571 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
572 | { | |
573 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
574 | } | |
575 | ||
4b6c2cca | 576 | static struct rcu_torture_ops sched_ops = { |
0acc512c | 577 | .init = rcu_sync_torture_init, |
0acc512c PM |
578 | .readlock = sched_torture_read_lock, |
579 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
580 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 581 | .completed = rcu_no_completed, |
0acc512c | 582 | .deferred_free = rcu_sched_torture_deferred_free, |
bdf2a436 | 583 | .sync = synchronize_sched, |
2ec1f2d9 PM |
584 | .exp_sync = synchronize_sched_expedited, |
585 | .call = call_rcu_sched, | |
0acc512c | 586 | .cb_barrier = rcu_barrier_sched, |
bf66f18e | 587 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
588 | .stats = NULL, |
589 | .irq_capable = 1, | |
590 | .name = "sched" | |
4b6c2cca JT |
591 | }; |
592 | ||
8e8be45e PM |
593 | /* |
594 | * RCU torture priority-boost testing. Runs one real-time thread per | |
595 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
596 | * spinning waiting for them to be invoked. If a given callback takes | |
597 | * too long to be invoked, we assume that priority inversion has occurred. | |
598 | */ | |
599 | ||
600 | struct rcu_boost_inflight { | |
601 | struct rcu_head rcu; | |
602 | int inflight; | |
603 | }; | |
604 | ||
605 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
606 | { | |
607 | struct rcu_boost_inflight *rbip = | |
608 | container_of(head, struct rcu_boost_inflight, rcu); | |
609 | ||
610 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
611 | rbip->inflight = 0; | |
612 | } | |
613 | ||
614 | static int rcu_torture_boost(void *arg) | |
615 | { | |
616 | unsigned long call_rcu_time; | |
617 | unsigned long endtime; | |
618 | unsigned long oldstarttime; | |
619 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
620 | struct sched_param sp; | |
621 | ||
622 | VERBOSE_PRINTK_STRING("rcu_torture_boost started"); | |
623 | ||
624 | /* Set real-time priority. */ | |
625 | sp.sched_priority = 1; | |
626 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
627 | VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!"); | |
628 | n_rcu_torture_boost_rterror++; | |
629 | } | |
630 | ||
561190e3 | 631 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
632 | /* Each pass through the following loop does one boost-test cycle. */ |
633 | do { | |
634 | /* Wait for the next test interval. */ | |
635 | oldstarttime = boost_starttime; | |
93898fb1 | 636 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
0e11c8e8 | 637 | schedule_timeout_interruptible(oldstarttime - jiffies); |
8e8be45e PM |
638 | rcu_stutter_wait("rcu_torture_boost"); |
639 | if (kthread_should_stop() || | |
640 | fullstop != FULLSTOP_DONTSTOP) | |
641 | goto checkwait; | |
642 | } | |
643 | ||
644 | /* Do one boost-test interval. */ | |
645 | endtime = oldstarttime + test_boost_duration * HZ; | |
646 | call_rcu_time = jiffies; | |
93898fb1 | 647 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e PM |
648 | /* If we don't have a callback in flight, post one. */ |
649 | if (!rbi.inflight) { | |
650 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
651 | rbi.inflight = 1; | |
652 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
653 | if (jiffies - call_rcu_time > | |
654 | test_boost_duration * HZ - HZ / 2) { | |
655 | VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed"); | |
656 | n_rcu_torture_boost_failure++; | |
657 | } | |
658 | call_rcu_time = jiffies; | |
659 | } | |
660 | cond_resched(); | |
661 | rcu_stutter_wait("rcu_torture_boost"); | |
662 | if (kthread_should_stop() || | |
663 | fullstop != FULLSTOP_DONTSTOP) | |
664 | goto checkwait; | |
665 | } | |
666 | ||
667 | /* | |
668 | * Set the start time of the next test interval. | |
669 | * Yes, this is vulnerable to long delays, but such | |
670 | * delays simply cause a false negative for the next | |
671 | * interval. Besides, we are running at RT priority, | |
672 | * so delays should be relatively rare. | |
673 | */ | |
ab8f11e5 PM |
674 | while (oldstarttime == boost_starttime && |
675 | !kthread_should_stop()) { | |
8e8be45e PM |
676 | if (mutex_trylock(&boost_mutex)) { |
677 | boost_starttime = jiffies + | |
678 | test_boost_interval * HZ; | |
679 | n_rcu_torture_boosts++; | |
680 | mutex_unlock(&boost_mutex); | |
681 | break; | |
682 | } | |
683 | schedule_timeout_uninterruptible(1); | |
684 | } | |
685 | ||
686 | /* Go do the stutter. */ | |
687 | checkwait: rcu_stutter_wait("rcu_torture_boost"); | |
688 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
689 | ||
690 | /* Clean up and exit. */ | |
691 | VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping"); | |
692 | rcutorture_shutdown_absorb("rcu_torture_boost"); | |
693 | while (!kthread_should_stop() || rbi.inflight) | |
694 | schedule_timeout_uninterruptible(1); | |
695 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ | |
9d68197c | 696 | destroy_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
697 | return 0; |
698 | } | |
699 | ||
bf66f18e PM |
700 | /* |
701 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
702 | * bursts of calls to force_quiescent_state(), increasing the probability | |
703 | * of occurrence of some important types of race conditions. | |
704 | */ | |
705 | static int | |
706 | rcu_torture_fqs(void *arg) | |
707 | { | |
708 | unsigned long fqs_resume_time; | |
709 | int fqs_burst_remaining; | |
710 | ||
711 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task started"); | |
712 | do { | |
713 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
714 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
715 | !kthread_should_stop()) { | |
bf66f18e PM |
716 | schedule_timeout_interruptible(1); |
717 | } | |
718 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
719 | while (fqs_burst_remaining > 0 && |
720 | !kthread_should_stop()) { | |
bf66f18e PM |
721 | cur_ops->fqs(); |
722 | udelay(fqs_holdoff); | |
723 | fqs_burst_remaining -= fqs_holdoff; | |
724 | } | |
725 | rcu_stutter_wait("rcu_torture_fqs"); | |
726 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
727 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping"); | |
728 | rcutorture_shutdown_absorb("rcu_torture_fqs"); | |
729 | while (!kthread_should_stop()) | |
730 | schedule_timeout_uninterruptible(1); | |
731 | return 0; | |
732 | } | |
733 | ||
a241ec65 PM |
734 | /* |
735 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
736 | * for that pointed to by rcu_torture_current, freeing the old structure | |
737 | * after a series of grace periods (the "pipeline"). | |
738 | */ | |
739 | static int | |
740 | rcu_torture_writer(void *arg) | |
741 | { | |
2ec1f2d9 | 742 | bool exp; |
a241ec65 | 743 | int i; |
a241ec65 | 744 | struct rcu_torture *rp; |
2ec1f2d9 | 745 | struct rcu_torture *rp1; |
a241ec65 | 746 | struct rcu_torture *old_rp; |
51b1130e | 747 | static DEFINE_TORTURE_RANDOM(rand); |
a241ec65 PM |
748 | |
749 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
750 | set_user_nice(current, 19); |
751 | ||
a241ec65 PM |
752 | do { |
753 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
754 | rp = rcu_torture_alloc(); |
755 | if (rp == NULL) | |
a241ec65 PM |
756 | continue; |
757 | rp->rtort_pipe_count = 0; | |
51b1130e | 758 | udelay(torture_random(&rand) & 0x3ff); |
0ddea0ea PM |
759 | old_rp = rcu_dereference_check(rcu_torture_current, |
760 | current == writer_task); | |
996417d2 | 761 | rp->rtort_mbtest = 1; |
a241ec65 | 762 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 763 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 764 | if (old_rp) { |
a241ec65 PM |
765 | i = old_rp->rtort_pipe_count; |
766 | if (i > RCU_TORTURE_PIPE_LEN) | |
767 | i = RCU_TORTURE_PIPE_LEN; | |
768 | atomic_inc(&rcu_torture_wcount[i]); | |
769 | old_rp->rtort_pipe_count++; | |
2ec1f2d9 | 770 | if (gp_normal == gp_exp) |
51b1130e | 771 | exp = !!(torture_random(&rand) & 0x80); |
2ec1f2d9 PM |
772 | else |
773 | exp = gp_exp; | |
774 | if (!exp) { | |
775 | cur_ops->deferred_free(old_rp); | |
776 | } else { | |
777 | cur_ops->exp_sync(); | |
778 | list_add(&old_rp->rtort_free, | |
779 | &rcu_torture_removed); | |
780 | list_for_each_entry_safe(rp, rp1, | |
781 | &rcu_torture_removed, | |
782 | rtort_free) { | |
783 | i = rp->rtort_pipe_count; | |
784 | if (i > RCU_TORTURE_PIPE_LEN) | |
785 | i = RCU_TORTURE_PIPE_LEN; | |
786 | atomic_inc(&rcu_torture_wcount[i]); | |
787 | if (++rp->rtort_pipe_count >= | |
788 | RCU_TORTURE_PIPE_LEN) { | |
789 | rp->rtort_mbtest = 0; | |
790 | list_del(&rp->rtort_free); | |
791 | rcu_torture_free(rp); | |
792 | } | |
793 | } | |
794 | } | |
a241ec65 | 795 | } |
4a298656 | 796 | rcutorture_record_progress(++rcu_torture_current_version); |
c9d557c1 PM |
797 | rcu_stutter_wait("rcu_torture_writer"); |
798 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 799 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
800 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
801 | while (!kthread_should_stop()) | |
a241ec65 PM |
802 | schedule_timeout_uninterruptible(1); |
803 | return 0; | |
804 | } | |
805 | ||
b772e1dd JT |
806 | /* |
807 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
808 | * delay between calls. | |
809 | */ | |
810 | static int | |
811 | rcu_torture_fakewriter(void *arg) | |
812 | { | |
51b1130e | 813 | DEFINE_TORTURE_RANDOM(rand); |
b772e1dd JT |
814 | |
815 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
816 | set_user_nice(current, 19); | |
817 | ||
818 | do { | |
51b1130e PM |
819 | schedule_timeout_uninterruptible(1 + torture_random(&rand)%10); |
820 | udelay(torture_random(&rand) & 0x3ff); | |
72472a02 | 821 | if (cur_ops->cb_barrier != NULL && |
51b1130e | 822 | torture_random(&rand) % (nfakewriters * 8) == 0) { |
72472a02 | 823 | cur_ops->cb_barrier(); |
2ec1f2d9 | 824 | } else if (gp_normal == gp_exp) { |
51b1130e | 825 | if (torture_random(&rand) & 0x80) |
2ec1f2d9 PM |
826 | cur_ops->sync(); |
827 | else | |
828 | cur_ops->exp_sync(); | |
829 | } else if (gp_normal) { | |
72472a02 | 830 | cur_ops->sync(); |
2ec1f2d9 PM |
831 | } else { |
832 | cur_ops->exp_sync(); | |
833 | } | |
c9d557c1 PM |
834 | rcu_stutter_wait("rcu_torture_fakewriter"); |
835 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
836 | |
837 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
838 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
839 | while (!kthread_should_stop()) | |
b772e1dd JT |
840 | schedule_timeout_uninterruptible(1); |
841 | return 0; | |
842 | } | |
843 | ||
91afaf30 PM |
844 | void rcutorture_trace_dump(void) |
845 | { | |
846 | static atomic_t beenhere = ATOMIC_INIT(0); | |
847 | ||
848 | if (atomic_read(&beenhere)) | |
849 | return; | |
850 | if (atomic_xchg(&beenhere, 1) != 0) | |
851 | return; | |
91afaf30 PM |
852 | ftrace_dump(DUMP_ALL); |
853 | } | |
854 | ||
0729fbf3 PM |
855 | /* |
856 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
857 | * incrementing the corresponding element of the pipeline array. The | |
858 | * counter in the element should never be greater than 1, otherwise, the | |
859 | * RCU implementation is broken. | |
860 | */ | |
861 | static void rcu_torture_timer(unsigned long unused) | |
862 | { | |
863 | int idx; | |
864 | int completed; | |
52494535 | 865 | int completed_end; |
51b1130e | 866 | static DEFINE_TORTURE_RANDOM(rand); |
0729fbf3 PM |
867 | static DEFINE_SPINLOCK(rand_lock); |
868 | struct rcu_torture *p; | |
869 | int pipe_count; | |
52494535 | 870 | unsigned long long ts; |
0729fbf3 PM |
871 | |
872 | idx = cur_ops->readlock(); | |
873 | completed = cur_ops->completed(); | |
e4aa0da3 | 874 | ts = rcu_trace_clock_local(); |
632ee200 | 875 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
876 | rcu_read_lock_bh_held() || |
877 | rcu_read_lock_sched_held() || | |
878 | srcu_read_lock_held(&srcu_ctl)); | |
0729fbf3 PM |
879 | if (p == NULL) { |
880 | /* Leave because rcu_torture_writer is not yet underway */ | |
881 | cur_ops->readunlock(idx); | |
882 | return; | |
883 | } | |
884 | if (p->rtort_mbtest == 0) | |
885 | atomic_inc(&n_rcu_torture_mberror); | |
886 | spin_lock(&rand_lock); | |
0acc512c | 887 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
888 | n_rcu_torture_timers++; |
889 | spin_unlock(&rand_lock); | |
890 | preempt_disable(); | |
891 | pipe_count = p->rtort_pipe_count; | |
892 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
893 | /* Should not happen, but... */ | |
894 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
895 | } | |
52494535 PM |
896 | completed_end = cur_ops->completed(); |
897 | if (pipe_count > 1) { | |
52494535 PM |
898 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts, |
899 | completed, completed_end); | |
91afaf30 | 900 | rcutorture_trace_dump(); |
52494535 | 901 | } |
dd17c8f7 | 902 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
52494535 | 903 | completed = completed_end - completed; |
0729fbf3 PM |
904 | if (completed > RCU_TORTURE_PIPE_LEN) { |
905 | /* Should not happen, but... */ | |
906 | completed = RCU_TORTURE_PIPE_LEN; | |
907 | } | |
dd17c8f7 | 908 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
909 | preempt_enable(); |
910 | cur_ops->readunlock(idx); | |
911 | } | |
912 | ||
a241ec65 PM |
913 | /* |
914 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
915 | * incrementing the corresponding element of the pipeline array. The | |
916 | * counter in the element should never be greater than 1, otherwise, the | |
917 | * RCU implementation is broken. | |
918 | */ | |
919 | static int | |
920 | rcu_torture_reader(void *arg) | |
921 | { | |
922 | int completed; | |
52494535 | 923 | int completed_end; |
72e9bb54 | 924 | int idx; |
51b1130e | 925 | DEFINE_TORTURE_RANDOM(rand); |
a241ec65 PM |
926 | struct rcu_torture *p; |
927 | int pipe_count; | |
0729fbf3 | 928 | struct timer_list t; |
52494535 | 929 | unsigned long long ts; |
a241ec65 PM |
930 | |
931 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 932 | set_user_nice(current, 19); |
0acc512c | 933 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 934 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 935 | |
a241ec65 | 936 | do { |
0acc512c | 937 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 938 | if (!timer_pending(&t)) |
6155fec9 | 939 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 940 | } |
72e9bb54 PM |
941 | idx = cur_ops->readlock(); |
942 | completed = cur_ops->completed(); | |
e4aa0da3 | 943 | ts = rcu_trace_clock_local(); |
632ee200 | 944 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
945 | rcu_read_lock_bh_held() || |
946 | rcu_read_lock_sched_held() || | |
947 | srcu_read_lock_held(&srcu_ctl)); | |
a241ec65 PM |
948 | if (p == NULL) { |
949 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 950 | cur_ops->readunlock(idx); |
a241ec65 PM |
951 | schedule_timeout_interruptible(HZ); |
952 | continue; | |
953 | } | |
996417d2 PM |
954 | if (p->rtort_mbtest == 0) |
955 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 956 | cur_ops->read_delay(&rand); |
a241ec65 PM |
957 | preempt_disable(); |
958 | pipe_count = p->rtort_pipe_count; | |
959 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
960 | /* Should not happen, but... */ | |
961 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
962 | } | |
52494535 PM |
963 | completed_end = cur_ops->completed(); |
964 | if (pipe_count > 1) { | |
52494535 PM |
965 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, |
966 | ts, completed, completed_end); | |
91afaf30 | 967 | rcutorture_trace_dump(); |
52494535 | 968 | } |
dd17c8f7 | 969 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
52494535 | 970 | completed = completed_end - completed; |
a241ec65 PM |
971 | if (completed > RCU_TORTURE_PIPE_LEN) { |
972 | /* Should not happen, but... */ | |
973 | completed = RCU_TORTURE_PIPE_LEN; | |
974 | } | |
dd17c8f7 | 975 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 976 | preempt_enable(); |
72e9bb54 | 977 | cur_ops->readunlock(idx); |
a241ec65 | 978 | schedule(); |
c9d557c1 PM |
979 | rcu_stutter_wait("rcu_torture_reader"); |
980 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 981 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 982 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0acc512c | 983 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 984 | del_timer_sync(&t); |
c9d557c1 | 985 | while (!kthread_should_stop()) |
a241ec65 PM |
986 | schedule_timeout_uninterruptible(1); |
987 | return 0; | |
988 | } | |
989 | ||
990 | /* | |
991 | * Create an RCU-torture statistics message in the specified buffer. | |
992 | */ | |
d1008950 | 993 | static void |
a241ec65 PM |
994 | rcu_torture_printk(char *page) |
995 | { | |
a241ec65 PM |
996 | int cpu; |
997 | int i; | |
998 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
999 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1000 | ||
0a945022 | 1001 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1002 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1003 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
1004 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
1005 | } | |
1006 | } | |
1007 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
1008 | if (pipesummary[i] != 0) | |
1009 | break; | |
1010 | } | |
d1008950 CG |
1011 | page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG); |
1012 | page += sprintf(page, | |
5cf05ad7 | 1013 | "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", |
a241ec65 PM |
1014 | rcu_torture_current, |
1015 | rcu_torture_current_version, | |
1016 | list_empty(&rcu_torture_freelist), | |
1017 | atomic_read(&n_rcu_torture_alloc), | |
1018 | atomic_read(&n_rcu_torture_alloc_fail), | |
5cf05ad7 | 1019 | atomic_read(&n_rcu_torture_free)); |
d1008950 | 1020 | page += sprintf(page, "rtmbe: %d rtbke: %ld rtbre: %ld ", |
0729fbf3 | 1021 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e | 1022 | n_rcu_torture_boost_ktrerror, |
5cf05ad7 | 1023 | n_rcu_torture_boost_rterror); |
d1008950 | 1024 | page += sprintf(page, "rtbf: %ld rtb: %ld nt: %ld ", |
8e8be45e PM |
1025 | n_rcu_torture_boost_failure, |
1026 | n_rcu_torture_boosts, | |
5cf05ad7 | 1027 | n_rcu_torture_timers); |
d1008950 | 1028 | page += sprintf(page, |
13dbf914 PM |
1029 | "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ", |
1030 | n_online_successes, n_online_attempts, | |
1031 | n_offline_successes, n_offline_attempts, | |
1032 | min_online, max_online, | |
1033 | min_offline, max_offline, | |
1034 | sum_online, sum_offline, HZ); | |
d1008950 | 1035 | page += sprintf(page, "barrier: %ld/%ld:%ld", |
fae4b54f PM |
1036 | n_barrier_successes, |
1037 | n_barrier_attempts, | |
1038 | n_rcu_torture_barrier_error); | |
d1008950 | 1039 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); |
8e8be45e | 1040 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
fae4b54f | 1041 | n_rcu_torture_barrier_error != 0 || |
8e8be45e PM |
1042 | n_rcu_torture_boost_ktrerror != 0 || |
1043 | n_rcu_torture_boost_rterror != 0 || | |
fae4b54f PM |
1044 | n_rcu_torture_boost_failure != 0 || |
1045 | i > 1) { | |
d1008950 | 1046 | page += sprintf(page, "!!! "); |
996417d2 | 1047 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 1048 | WARN_ON_ONCE(1); |
996417d2 | 1049 | } |
d1008950 | 1050 | page += sprintf(page, "Reader Pipe: "); |
a241ec65 | 1051 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
d1008950 CG |
1052 | page += sprintf(page, " %ld", pipesummary[i]); |
1053 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); | |
1054 | page += sprintf(page, "Reader Batch: "); | |
72e9bb54 | 1055 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
d1008950 CG |
1056 | page += sprintf(page, " %ld", batchsummary[i]); |
1057 | page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); | |
1058 | page += sprintf(page, "Free-Block Circulation: "); | |
a241ec65 | 1059 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
d1008950 | 1060 | page += sprintf(page, " %d", |
a241ec65 PM |
1061 | atomic_read(&rcu_torture_wcount[i])); |
1062 | } | |
d1008950 | 1063 | page += sprintf(page, "\n"); |
c8e5b163 | 1064 | if (cur_ops->stats) |
d1008950 | 1065 | cur_ops->stats(page); |
a241ec65 PM |
1066 | } |
1067 | ||
1068 | /* | |
1069 | * Print torture statistics. Caller must ensure that there is only | |
1070 | * one call to this function at a given time!!! This is normally | |
1071 | * accomplished by relying on the module system to only have one copy | |
1072 | * of the module loaded, and then by giving the rcu_torture_stats | |
1073 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1074 | * thread is not running). | |
1075 | */ | |
1076 | static void | |
1077 | rcu_torture_stats_print(void) | |
1078 | { | |
d1008950 CG |
1079 | int size = nr_cpu_ids * 200 + 8192; |
1080 | char *buf; | |
a241ec65 | 1081 | |
d1008950 CG |
1082 | buf = kmalloc(size, GFP_KERNEL); |
1083 | if (!buf) { | |
1084 | pr_err("rcu-torture: Out of memory, need: %d", size); | |
1085 | return; | |
1086 | } | |
1087 | rcu_torture_printk(buf); | |
1088 | pr_alert("%s", buf); | |
1089 | kfree(buf); | |
a241ec65 PM |
1090 | } |
1091 | ||
1092 | /* | |
1093 | * Periodically prints torture statistics, if periodic statistics printing | |
1094 | * was specified via the stat_interval module parameter. | |
1095 | * | |
1096 | * No need to worry about fullstop here, since this one doesn't reference | |
1097 | * volatile state or register callbacks. | |
1098 | */ | |
1099 | static int | |
1100 | rcu_torture_stats(void *arg) | |
1101 | { | |
1102 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
1103 | do { | |
1104 | schedule_timeout_interruptible(stat_interval * HZ); | |
1105 | rcu_torture_stats_print(); | |
c9d557c1 PM |
1106 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
1107 | } while (!kthread_should_stop()); | |
a241ec65 PM |
1108 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
1109 | return 0; | |
1110 | } | |
1111 | ||
d84f5203 SV |
1112 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
1113 | ||
1114 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
1115 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
1116 | */ | |
b2896d2e | 1117 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 1118 | { |
d84f5203 SV |
1119 | int i; |
1120 | ||
73d0a4b1 | 1121 | cpumask_setall(shuffle_tmp_mask); |
86ef5c9a | 1122 | get_online_cpus(); |
d84f5203 SV |
1123 | |
1124 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
1125 | if (num_online_cpus() == 1) { |
1126 | put_online_cpus(); | |
1127 | return; | |
1128 | } | |
d84f5203 SV |
1129 | |
1130 | if (rcu_idle_cpu != -1) | |
73d0a4b1 | 1131 | cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); |
d84f5203 | 1132 | |
73d0a4b1 | 1133 | set_cpus_allowed_ptr(current, shuffle_tmp_mask); |
d84f5203 | 1134 | |
c8e5b163 | 1135 | if (reader_tasks) { |
d84f5203 SV |
1136 | for (i = 0; i < nrealreaders; i++) |
1137 | if (reader_tasks[i]) | |
f70316da | 1138 | set_cpus_allowed_ptr(reader_tasks[i], |
73d0a4b1 | 1139 | shuffle_tmp_mask); |
d84f5203 | 1140 | } |
c8e5b163 | 1141 | if (fakewriter_tasks) { |
b772e1dd JT |
1142 | for (i = 0; i < nfakewriters; i++) |
1143 | if (fakewriter_tasks[i]) | |
f70316da | 1144 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
73d0a4b1 | 1145 | shuffle_tmp_mask); |
b772e1dd | 1146 | } |
d84f5203 | 1147 | if (writer_task) |
73d0a4b1 | 1148 | set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); |
d84f5203 | 1149 | if (stats_task) |
73d0a4b1 | 1150 | set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); |
0e11c8e8 PM |
1151 | if (stutter_task) |
1152 | set_cpus_allowed_ptr(stutter_task, shuffle_tmp_mask); | |
1153 | if (fqs_task) | |
1154 | set_cpus_allowed_ptr(fqs_task, shuffle_tmp_mask); | |
1155 | if (shutdown_task) | |
1156 | set_cpus_allowed_ptr(shutdown_task, shuffle_tmp_mask); | |
1157 | #ifdef CONFIG_HOTPLUG_CPU | |
1158 | if (onoff_task) | |
1159 | set_cpus_allowed_ptr(onoff_task, shuffle_tmp_mask); | |
1160 | #endif /* #ifdef CONFIG_HOTPLUG_CPU */ | |
1161 | if (stall_task) | |
1162 | set_cpus_allowed_ptr(stall_task, shuffle_tmp_mask); | |
1163 | if (barrier_cbs_tasks) | |
1164 | for (i = 0; i < n_barrier_cbs; i++) | |
1165 | if (barrier_cbs_tasks[i]) | |
1166 | set_cpus_allowed_ptr(barrier_cbs_tasks[i], | |
1167 | shuffle_tmp_mask); | |
1168 | if (barrier_task) | |
1169 | set_cpus_allowed_ptr(barrier_task, shuffle_tmp_mask); | |
d84f5203 SV |
1170 | |
1171 | if (rcu_idle_cpu == -1) | |
1172 | rcu_idle_cpu = num_online_cpus() - 1; | |
1173 | else | |
1174 | rcu_idle_cpu--; | |
1175 | ||
86ef5c9a | 1176 | put_online_cpus(); |
d84f5203 SV |
1177 | } |
1178 | ||
1179 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
1180 | * system to become idle at a time and cut off its timer ticks. This is meant | |
1181 | * to test the support for such tickless idle CPU in RCU. | |
1182 | */ | |
1183 | static int | |
1184 | rcu_torture_shuffle(void *arg) | |
1185 | { | |
1186 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
1187 | do { | |
1188 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
1189 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
1190 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
1191 | } while (!kthread_should_stop()); | |
d84f5203 SV |
1192 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
1193 | return 0; | |
1194 | } | |
1195 | ||
d120f65f PM |
1196 | /* Cause the rcutorture test to "stutter", starting and stopping all |
1197 | * threads periodically. | |
1198 | */ | |
1199 | static int | |
1200 | rcu_torture_stutter(void *arg) | |
1201 | { | |
1202 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
1203 | do { | |
1204 | schedule_timeout_interruptible(stutter * HZ); | |
1205 | stutter_pause_test = 1; | |
c9d557c1 | 1206 | if (!kthread_should_stop()) |
d120f65f PM |
1207 | schedule_timeout_interruptible(stutter * HZ); |
1208 | stutter_pause_test = 0; | |
c9d557c1 PM |
1209 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
1210 | } while (!kthread_should_stop()); | |
d120f65f PM |
1211 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
1212 | return 0; | |
1213 | } | |
1214 | ||
95c38322 | 1215 | static inline void |
e66c33d5 | 1216 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) |
95c38322 | 1217 | { |
2caa1e44 PM |
1218 | pr_alert("%s" TORTURE_FLAG |
1219 | "--- %s: nreaders=%d nfakewriters=%d " | |
1220 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " | |
1221 | "shuffle_interval=%d stutter=%d irqreader=%d " | |
1222 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " | |
1223 | "test_boost=%d/%d test_boost_interval=%d " | |
1224 | "test_boost_duration=%d shutdown_secs=%d " | |
67afeed2 PM |
1225 | "stall_cpu=%d stall_cpu_holdoff=%d " |
1226 | "n_barrier_cbs=%d " | |
2caa1e44 PM |
1227 | "onoff_interval=%d onoff_holdoff=%d\n", |
1228 | torture_type, tag, nrealreaders, nfakewriters, | |
1229 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, | |
1230 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, | |
1231 | test_boost, cur_ops->can_boost, | |
1232 | test_boost_interval, test_boost_duration, shutdown_secs, | |
67afeed2 PM |
1233 | stall_cpu, stall_cpu_holdoff, |
1234 | n_barrier_cbs, | |
2caa1e44 | 1235 | onoff_interval, onoff_holdoff); |
95c38322 PM |
1236 | } |
1237 | ||
8e8be45e | 1238 | static struct notifier_block rcutorture_shutdown_nb = { |
343e9099 PM |
1239 | .notifier_call = rcutorture_shutdown_notify, |
1240 | }; | |
1241 | ||
8e8be45e PM |
1242 | static void rcutorture_booster_cleanup(int cpu) |
1243 | { | |
1244 | struct task_struct *t; | |
1245 | ||
1246 | if (boost_tasks[cpu] == NULL) | |
1247 | return; | |
1248 | mutex_lock(&boost_mutex); | |
1249 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task"); | |
1250 | t = boost_tasks[cpu]; | |
1251 | boost_tasks[cpu] = NULL; | |
1252 | mutex_unlock(&boost_mutex); | |
1253 | ||
1254 | /* This must be outside of the mutex, otherwise deadlock! */ | |
1255 | kthread_stop(t); | |
37e377d2 | 1256 | boost_tasks[cpu] = NULL; |
8e8be45e PM |
1257 | } |
1258 | ||
1259 | static int rcutorture_booster_init(int cpu) | |
1260 | { | |
1261 | int retval; | |
1262 | ||
1263 | if (boost_tasks[cpu] != NULL) | |
1264 | return 0; /* Already created, nothing more to do. */ | |
1265 | ||
1266 | /* Don't allow time recalculation while creating a new task. */ | |
1267 | mutex_lock(&boost_mutex); | |
1268 | VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task"); | |
1f288094 ED |
1269 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1270 | cpu_to_node(cpu), | |
1271 | "rcu_torture_boost"); | |
8e8be45e PM |
1272 | if (IS_ERR(boost_tasks[cpu])) { |
1273 | retval = PTR_ERR(boost_tasks[cpu]); | |
1274 | VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed"); | |
1275 | n_rcu_torture_boost_ktrerror++; | |
1276 | boost_tasks[cpu] = NULL; | |
1277 | mutex_unlock(&boost_mutex); | |
1278 | return retval; | |
1279 | } | |
1280 | kthread_bind(boost_tasks[cpu], cpu); | |
1281 | wake_up_process(boost_tasks[cpu]); | |
1282 | mutex_unlock(&boost_mutex); | |
1283 | return 0; | |
1284 | } | |
1285 | ||
d5f546d8 PM |
1286 | /* |
1287 | * Cause the rcutorture test to shutdown the system after the test has | |
1288 | * run for the time specified by the shutdown_secs module parameter. | |
1289 | */ | |
1290 | static int | |
1291 | rcu_torture_shutdown(void *arg) | |
1292 | { | |
1293 | long delta; | |
1294 | unsigned long jiffies_snap; | |
1295 | ||
1296 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started"); | |
1297 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1298 | while (ULONG_CMP_LT(jiffies_snap, shutdown_time) && | |
1299 | !kthread_should_stop()) { | |
1300 | delta = shutdown_time - jiffies_snap; | |
1301 | if (verbose) | |
2caa1e44 PM |
1302 | pr_alert("%s" TORTURE_FLAG |
1303 | "rcu_torture_shutdown task: %lu jiffies remaining\n", | |
1304 | torture_type, delta); | |
d5f546d8 PM |
1305 | schedule_timeout_interruptible(delta); |
1306 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1307 | } | |
b58bdcca | 1308 | if (kthread_should_stop()) { |
d5f546d8 PM |
1309 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping"); |
1310 | return 0; | |
1311 | } | |
1312 | ||
1313 | /* OK, shut down the system. */ | |
1314 | ||
1315 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system"); | |
1316 | shutdown_task = NULL; /* Avoid self-kill deadlock. */ | |
1317 | rcu_torture_cleanup(); /* Get the success/failure message. */ | |
1318 | kernel_power_off(); /* Shut down the system. */ | |
1319 | return 0; | |
1320 | } | |
1321 | ||
b58bdcca PM |
1322 | #ifdef CONFIG_HOTPLUG_CPU |
1323 | ||
1324 | /* | |
1325 | * Execute random CPU-hotplug operations at the interval specified | |
1326 | * by the onoff_interval. | |
1327 | */ | |
49fb4c62 | 1328 | static int |
b58bdcca PM |
1329 | rcu_torture_onoff(void *arg) |
1330 | { | |
1331 | int cpu; | |
13dbf914 | 1332 | unsigned long delta; |
b58bdcca | 1333 | int maxcpu = -1; |
51b1130e | 1334 | DEFINE_TORTURE_RANDOM(rand); |
48983260 | 1335 | int ret; |
13dbf914 | 1336 | unsigned long starttime; |
b58bdcca PM |
1337 | |
1338 | VERBOSE_PRINTK_STRING("rcu_torture_onoff task started"); | |
1339 | for_each_online_cpu(cpu) | |
1340 | maxcpu = cpu; | |
1341 | WARN_ON(maxcpu < 0); | |
9b9ec9b9 PM |
1342 | if (onoff_holdoff > 0) { |
1343 | VERBOSE_PRINTK_STRING("rcu_torture_onoff begin holdoff"); | |
1344 | schedule_timeout_interruptible(onoff_holdoff * HZ); | |
1345 | VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff"); | |
1346 | } | |
b58bdcca | 1347 | while (!kthread_should_stop()) { |
51b1130e | 1348 | cpu = (torture_random(&rand) >> 4) % (maxcpu + 1); |
f220242a | 1349 | if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) { |
b58bdcca | 1350 | if (verbose) |
2caa1e44 PM |
1351 | pr_alert("%s" TORTURE_FLAG |
1352 | "rcu_torture_onoff task: offlining %d\n", | |
1353 | torture_type, cpu); | |
13dbf914 | 1354 | starttime = jiffies; |
b58bdcca | 1355 | n_offline_attempts++; |
48983260 PM |
1356 | ret = cpu_down(cpu); |
1357 | if (ret) { | |
1358 | if (verbose) | |
1359 | pr_alert("%s" TORTURE_FLAG | |
1360 | "rcu_torture_onoff task: offline %d failed: errno %d\n", | |
1361 | torture_type, cpu, ret); | |
1362 | } else { | |
b58bdcca | 1363 | if (verbose) |
2caa1e44 PM |
1364 | pr_alert("%s" TORTURE_FLAG |
1365 | "rcu_torture_onoff task: offlined %d\n", | |
1366 | torture_type, cpu); | |
b58bdcca | 1367 | n_offline_successes++; |
13dbf914 PM |
1368 | delta = jiffies - starttime; |
1369 | sum_offline += delta; | |
1370 | if (min_offline < 0) { | |
1371 | min_offline = delta; | |
1372 | max_offline = delta; | |
1373 | } | |
1374 | if (min_offline > delta) | |
1375 | min_offline = delta; | |
1376 | if (max_offline < delta) | |
1377 | max_offline = delta; | |
b58bdcca | 1378 | } |
f220242a | 1379 | } else if (cpu_is_hotpluggable(cpu)) { |
b58bdcca | 1380 | if (verbose) |
2caa1e44 PM |
1381 | pr_alert("%s" TORTURE_FLAG |
1382 | "rcu_torture_onoff task: onlining %d\n", | |
1383 | torture_type, cpu); | |
13dbf914 | 1384 | starttime = jiffies; |
b58bdcca | 1385 | n_online_attempts++; |
7a6a4107 PM |
1386 | ret = cpu_up(cpu); |
1387 | if (ret) { | |
1388 | if (verbose) | |
1389 | pr_alert("%s" TORTURE_FLAG | |
1390 | "rcu_torture_onoff task: online %d failed: errno %d\n", | |
1391 | torture_type, cpu, ret); | |
1392 | } else { | |
b58bdcca | 1393 | if (verbose) |
2caa1e44 PM |
1394 | pr_alert("%s" TORTURE_FLAG |
1395 | "rcu_torture_onoff task: onlined %d\n", | |
1396 | torture_type, cpu); | |
b58bdcca | 1397 | n_online_successes++; |
13dbf914 PM |
1398 | delta = jiffies - starttime; |
1399 | sum_online += delta; | |
1400 | if (min_online < 0) { | |
1401 | min_online = delta; | |
1402 | max_online = delta; | |
1403 | } | |
1404 | if (min_online > delta) | |
1405 | min_online = delta; | |
1406 | if (max_online < delta) | |
1407 | max_online = delta; | |
b58bdcca PM |
1408 | } |
1409 | } | |
1410 | schedule_timeout_interruptible(onoff_interval * HZ); | |
1411 | } | |
1412 | VERBOSE_PRINTK_STRING("rcu_torture_onoff task stopping"); | |
1413 | return 0; | |
1414 | } | |
1415 | ||
49fb4c62 | 1416 | static int |
b58bdcca PM |
1417 | rcu_torture_onoff_init(void) |
1418 | { | |
3c1b1ce0 JL |
1419 | int ret; |
1420 | ||
b58bdcca PM |
1421 | if (onoff_interval <= 0) |
1422 | return 0; | |
1423 | onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff"); | |
1424 | if (IS_ERR(onoff_task)) { | |
3c1b1ce0 | 1425 | ret = PTR_ERR(onoff_task); |
b58bdcca | 1426 | onoff_task = NULL; |
3c1b1ce0 | 1427 | return ret; |
b58bdcca PM |
1428 | } |
1429 | return 0; | |
1430 | } | |
1431 | ||
1432 | static void rcu_torture_onoff_cleanup(void) | |
1433 | { | |
1434 | if (onoff_task == NULL) | |
1435 | return; | |
1436 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task"); | |
1437 | kthread_stop(onoff_task); | |
37e377d2 | 1438 | onoff_task = NULL; |
b58bdcca PM |
1439 | } |
1440 | ||
1441 | #else /* #ifdef CONFIG_HOTPLUG_CPU */ | |
1442 | ||
37e377d2 | 1443 | static int |
b58bdcca PM |
1444 | rcu_torture_onoff_init(void) |
1445 | { | |
37e377d2 | 1446 | return 0; |
b58bdcca PM |
1447 | } |
1448 | ||
1449 | static void rcu_torture_onoff_cleanup(void) | |
1450 | { | |
1451 | } | |
1452 | ||
1453 | #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ | |
1454 | ||
c13f3757 PM |
1455 | /* |
1456 | * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then | |
1457 | * induces a CPU stall for the time specified by stall_cpu. | |
1458 | */ | |
49fb4c62 | 1459 | static int rcu_torture_stall(void *args) |
c13f3757 PM |
1460 | { |
1461 | unsigned long stop_at; | |
1462 | ||
1463 | VERBOSE_PRINTK_STRING("rcu_torture_stall task started"); | |
1464 | if (stall_cpu_holdoff > 0) { | |
1465 | VERBOSE_PRINTK_STRING("rcu_torture_stall begin holdoff"); | |
1466 | schedule_timeout_interruptible(stall_cpu_holdoff * HZ); | |
1467 | VERBOSE_PRINTK_STRING("rcu_torture_stall end holdoff"); | |
1468 | } | |
1469 | if (!kthread_should_stop()) { | |
1470 | stop_at = get_seconds() + stall_cpu; | |
1471 | /* RCU CPU stall is expected behavior in following code. */ | |
2caa1e44 | 1472 | pr_alert("rcu_torture_stall start.\n"); |
c13f3757 PM |
1473 | rcu_read_lock(); |
1474 | preempt_disable(); | |
1475 | while (ULONG_CMP_LT(get_seconds(), stop_at)) | |
1476 | continue; /* Induce RCU CPU stall warning. */ | |
1477 | preempt_enable(); | |
1478 | rcu_read_unlock(); | |
2caa1e44 | 1479 | pr_alert("rcu_torture_stall end.\n"); |
c13f3757 PM |
1480 | } |
1481 | rcutorture_shutdown_absorb("rcu_torture_stall"); | |
1482 | while (!kthread_should_stop()) | |
1483 | schedule_timeout_interruptible(10 * HZ); | |
1484 | return 0; | |
1485 | } | |
1486 | ||
1487 | /* Spawn CPU-stall kthread, if stall_cpu specified. */ | |
1488 | static int __init rcu_torture_stall_init(void) | |
1489 | { | |
1490 | int ret; | |
1491 | ||
1492 | if (stall_cpu <= 0) | |
1493 | return 0; | |
1494 | stall_task = kthread_run(rcu_torture_stall, NULL, "rcu_torture_stall"); | |
1495 | if (IS_ERR(stall_task)) { | |
1496 | ret = PTR_ERR(stall_task); | |
1497 | stall_task = NULL; | |
1498 | return ret; | |
1499 | } | |
1500 | return 0; | |
1501 | } | |
1502 | ||
1503 | /* Clean up after the CPU-stall kthread, if one was spawned. */ | |
1504 | static void rcu_torture_stall_cleanup(void) | |
1505 | { | |
1506 | if (stall_task == NULL) | |
1507 | return; | |
1508 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task."); | |
1509 | kthread_stop(stall_task); | |
37e377d2 | 1510 | stall_task = NULL; |
c13f3757 PM |
1511 | } |
1512 | ||
fae4b54f PM |
1513 | /* Callback function for RCU barrier testing. */ |
1514 | void rcu_torture_barrier_cbf(struct rcu_head *rcu) | |
1515 | { | |
1516 | atomic_inc(&barrier_cbs_invoked); | |
1517 | } | |
1518 | ||
1519 | /* kthread function to register callbacks used to test RCU barriers. */ | |
1520 | static int rcu_torture_barrier_cbs(void *arg) | |
1521 | { | |
1522 | long myid = (long)arg; | |
c6ebcbb6 | 1523 | bool lastphase = 0; |
78e4bc34 | 1524 | bool newphase; |
fae4b54f PM |
1525 | struct rcu_head rcu; |
1526 | ||
1527 | init_rcu_head_on_stack(&rcu); | |
1528 | VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task started"); | |
1529 | set_user_nice(current, 19); | |
1530 | do { | |
1531 | wait_event(barrier_cbs_wq[myid], | |
78e4bc34 PM |
1532 | (newphase = |
1533 | ACCESS_ONCE(barrier_phase)) != lastphase || | |
fae4b54f PM |
1534 | kthread_should_stop() || |
1535 | fullstop != FULLSTOP_DONTSTOP); | |
78e4bc34 | 1536 | lastphase = newphase; |
c6ebcbb6 | 1537 | smp_mb(); /* ensure barrier_phase load before ->call(). */ |
fae4b54f PM |
1538 | if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) |
1539 | break; | |
1540 | cur_ops->call(&rcu, rcu_torture_barrier_cbf); | |
1541 | if (atomic_dec_and_test(&barrier_cbs_count)) | |
1542 | wake_up(&barrier_wq); | |
1543 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
1544 | VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task stopping"); | |
1545 | rcutorture_shutdown_absorb("rcu_torture_barrier_cbs"); | |
1546 | while (!kthread_should_stop()) | |
1547 | schedule_timeout_interruptible(1); | |
1548 | cur_ops->cb_barrier(); | |
1549 | destroy_rcu_head_on_stack(&rcu); | |
1550 | return 0; | |
1551 | } | |
1552 | ||
1553 | /* kthread function to drive and coordinate RCU barrier testing. */ | |
1554 | static int rcu_torture_barrier(void *arg) | |
1555 | { | |
1556 | int i; | |
1557 | ||
1558 | VERBOSE_PRINTK_STRING("rcu_torture_barrier task starting"); | |
1559 | do { | |
1560 | atomic_set(&barrier_cbs_invoked, 0); | |
1561 | atomic_set(&barrier_cbs_count, n_barrier_cbs); | |
c6ebcbb6 PM |
1562 | smp_mb(); /* Ensure barrier_phase after prior assignments. */ |
1563 | barrier_phase = !barrier_phase; | |
fae4b54f PM |
1564 | for (i = 0; i < n_barrier_cbs; i++) |
1565 | wake_up(&barrier_cbs_wq[i]); | |
1566 | wait_event(barrier_wq, | |
1567 | atomic_read(&barrier_cbs_count) == 0 || | |
1568 | kthread_should_stop() || | |
1569 | fullstop != FULLSTOP_DONTSTOP); | |
1570 | if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) | |
1571 | break; | |
1572 | n_barrier_attempts++; | |
78e4bc34 | 1573 | cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */ |
fae4b54f PM |
1574 | if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { |
1575 | n_rcu_torture_barrier_error++; | |
1576 | WARN_ON_ONCE(1); | |
1577 | } | |
1578 | n_barrier_successes++; | |
1579 | schedule_timeout_interruptible(HZ / 10); | |
1580 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
1581 | VERBOSE_PRINTK_STRING("rcu_torture_barrier task stopping"); | |
143aa672 | 1582 | rcutorture_shutdown_absorb("rcu_torture_barrier"); |
fae4b54f PM |
1583 | while (!kthread_should_stop()) |
1584 | schedule_timeout_interruptible(1); | |
1585 | return 0; | |
1586 | } | |
1587 | ||
1588 | /* Initialize RCU barrier testing. */ | |
1589 | static int rcu_torture_barrier_init(void) | |
1590 | { | |
1591 | int i; | |
1592 | int ret; | |
1593 | ||
1594 | if (n_barrier_cbs == 0) | |
1595 | return 0; | |
1596 | if (cur_ops->call == NULL || cur_ops->cb_barrier == NULL) { | |
2caa1e44 PM |
1597 | pr_alert("%s" TORTURE_FLAG |
1598 | " Call or barrier ops missing for %s,\n", | |
1599 | torture_type, cur_ops->name); | |
1600 | pr_alert("%s" TORTURE_FLAG | |
1601 | " RCU barrier testing omitted from run.\n", | |
1602 | torture_type); | |
fae4b54f PM |
1603 | return 0; |
1604 | } | |
1605 | atomic_set(&barrier_cbs_count, 0); | |
1606 | atomic_set(&barrier_cbs_invoked, 0); | |
1607 | barrier_cbs_tasks = | |
1608 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_tasks[0]), | |
1609 | GFP_KERNEL); | |
1610 | barrier_cbs_wq = | |
1611 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_wq[0]), | |
1612 | GFP_KERNEL); | |
de5e6437 | 1613 | if (barrier_cbs_tasks == NULL || !barrier_cbs_wq) |
fae4b54f PM |
1614 | return -ENOMEM; |
1615 | for (i = 0; i < n_barrier_cbs; i++) { | |
1616 | init_waitqueue_head(&barrier_cbs_wq[i]); | |
1617 | barrier_cbs_tasks[i] = kthread_run(rcu_torture_barrier_cbs, | |
9059c940 | 1618 | (void *)(long)i, |
fae4b54f PM |
1619 | "rcu_torture_barrier_cbs"); |
1620 | if (IS_ERR(barrier_cbs_tasks[i])) { | |
1621 | ret = PTR_ERR(barrier_cbs_tasks[i]); | |
1622 | VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier_cbs"); | |
1623 | barrier_cbs_tasks[i] = NULL; | |
1624 | return ret; | |
1625 | } | |
1626 | } | |
1627 | barrier_task = kthread_run(rcu_torture_barrier, NULL, | |
1628 | "rcu_torture_barrier"); | |
1629 | if (IS_ERR(barrier_task)) { | |
1630 | ret = PTR_ERR(barrier_task); | |
1631 | VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier"); | |
1632 | barrier_task = NULL; | |
1633 | } | |
1634 | return 0; | |
1635 | } | |
1636 | ||
1637 | /* Clean up after RCU barrier testing. */ | |
1638 | static void rcu_torture_barrier_cleanup(void) | |
1639 | { | |
1640 | int i; | |
1641 | ||
1642 | if (barrier_task != NULL) { | |
1643 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier task"); | |
1644 | kthread_stop(barrier_task); | |
1645 | barrier_task = NULL; | |
1646 | } | |
1647 | if (barrier_cbs_tasks != NULL) { | |
1648 | for (i = 0; i < n_barrier_cbs; i++) { | |
1649 | if (barrier_cbs_tasks[i] != NULL) { | |
1650 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier_cbs task"); | |
1651 | kthread_stop(barrier_cbs_tasks[i]); | |
1652 | barrier_cbs_tasks[i] = NULL; | |
1653 | } | |
1654 | } | |
1655 | kfree(barrier_cbs_tasks); | |
1656 | barrier_cbs_tasks = NULL; | |
1657 | } | |
1658 | if (barrier_cbs_wq != NULL) { | |
1659 | kfree(barrier_cbs_wq); | |
1660 | barrier_cbs_wq = NULL; | |
1661 | } | |
1662 | } | |
1663 | ||
8e8be45e PM |
1664 | static int rcutorture_cpu_notify(struct notifier_block *self, |
1665 | unsigned long action, void *hcpu) | |
1666 | { | |
1667 | long cpu = (long)hcpu; | |
1668 | ||
1669 | switch (action) { | |
1670 | case CPU_ONLINE: | |
1671 | case CPU_DOWN_FAILED: | |
1672 | (void)rcutorture_booster_init(cpu); | |
1673 | break; | |
1674 | case CPU_DOWN_PREPARE: | |
1675 | rcutorture_booster_cleanup(cpu); | |
1676 | break; | |
1677 | default: | |
1678 | break; | |
1679 | } | |
1680 | return NOTIFY_OK; | |
1681 | } | |
1682 | ||
1683 | static struct notifier_block rcutorture_cpu_nb = { | |
1684 | .notifier_call = rcutorture_cpu_notify, | |
1685 | }; | |
1686 | ||
a241ec65 PM |
1687 | static void |
1688 | rcu_torture_cleanup(void) | |
1689 | { | |
1690 | int i; | |
1691 | ||
343e9099 | 1692 | mutex_lock(&fullstop_mutex); |
4a298656 | 1693 | rcutorture_record_test_transition(); |
c9d557c1 | 1694 | if (fullstop == FULLSTOP_SHUTDOWN) { |
2caa1e44 | 1695 | pr_warn(/* but going down anyway, so... */ |
c9d557c1 | 1696 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); |
343e9099 | 1697 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 1698 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1699 | if (cur_ops->cb_barrier != NULL) |
1700 | cur_ops->cb_barrier(); | |
1701 | return; | |
1702 | } | |
c9d557c1 | 1703 | fullstop = FULLSTOP_RMMOD; |
343e9099 | 1704 | mutex_unlock(&fullstop_mutex); |
8e8be45e | 1705 | unregister_reboot_notifier(&rcutorture_shutdown_nb); |
fae4b54f | 1706 | rcu_torture_barrier_cleanup(); |
c13f3757 | 1707 | rcu_torture_stall_cleanup(); |
d120f65f PM |
1708 | if (stutter_task) { |
1709 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1710 | kthread_stop(stutter_task); | |
1711 | } | |
1712 | stutter_task = NULL; | |
c8e5b163 | 1713 | if (shuffler_task) { |
d84f5203 SV |
1714 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1715 | kthread_stop(shuffler_task); | |
73d0a4b1 | 1716 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1717 | } |
1718 | shuffler_task = NULL; | |
1719 | ||
c8e5b163 | 1720 | if (writer_task) { |
a241ec65 PM |
1721 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1722 | kthread_stop(writer_task); | |
1723 | } | |
1724 | writer_task = NULL; | |
1725 | ||
c8e5b163 | 1726 | if (reader_tasks) { |
a241ec65 | 1727 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1728 | if (reader_tasks[i]) { |
a241ec65 PM |
1729 | VERBOSE_PRINTK_STRING( |
1730 | "Stopping rcu_torture_reader task"); | |
1731 | kthread_stop(reader_tasks[i]); | |
1732 | } | |
1733 | reader_tasks[i] = NULL; | |
1734 | } | |
1735 | kfree(reader_tasks); | |
1736 | reader_tasks = NULL; | |
1737 | } | |
1738 | rcu_torture_current = NULL; | |
1739 | ||
c8e5b163 | 1740 | if (fakewriter_tasks) { |
b772e1dd | 1741 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1742 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1743 | VERBOSE_PRINTK_STRING( |
1744 | "Stopping rcu_torture_fakewriter task"); | |
1745 | kthread_stop(fakewriter_tasks[i]); | |
1746 | } | |
1747 | fakewriter_tasks[i] = NULL; | |
1748 | } | |
1749 | kfree(fakewriter_tasks); | |
1750 | fakewriter_tasks = NULL; | |
1751 | } | |
1752 | ||
c8e5b163 | 1753 | if (stats_task) { |
a241ec65 PM |
1754 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1755 | kthread_stop(stats_task); | |
1756 | } | |
1757 | stats_task = NULL; | |
1758 | ||
bf66f18e PM |
1759 | if (fqs_task) { |
1760 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task"); | |
1761 | kthread_stop(fqs_task); | |
1762 | } | |
1763 | fqs_task = NULL; | |
8e8be45e PM |
1764 | if ((test_boost == 1 && cur_ops->can_boost) || |
1765 | test_boost == 2) { | |
1766 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1767 | for_each_possible_cpu(i) | |
1768 | rcutorture_booster_cleanup(i); | |
1769 | } | |
d5f546d8 PM |
1770 | if (shutdown_task != NULL) { |
1771 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task"); | |
1772 | kthread_stop(shutdown_task); | |
1773 | } | |
37e377d2 | 1774 | shutdown_task = NULL; |
b58bdcca | 1775 | rcu_torture_onoff_cleanup(); |
bf66f18e | 1776 | |
a241ec65 | 1777 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1778 | |
1779 | if (cur_ops->cb_barrier != NULL) | |
1780 | cur_ops->cb_barrier(); | |
a241ec65 | 1781 | |
a241ec65 | 1782 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1783 | |
fae4b54f | 1784 | if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error) |
8e8be45e | 1785 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
091541bb PM |
1786 | else if (n_online_successes != n_online_attempts || |
1787 | n_offline_successes != n_offline_attempts) | |
1788 | rcu_torture_print_module_parms(cur_ops, | |
1789 | "End of test: RCU_HOTPLUG"); | |
95c38322 | 1790 | else |
8e8be45e | 1791 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1792 | } |
1793 | ||
d2818df1 PM |
1794 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD |
1795 | static void rcu_torture_leak_cb(struct rcu_head *rhp) | |
1796 | { | |
1797 | } | |
1798 | ||
1799 | static void rcu_torture_err_cb(struct rcu_head *rhp) | |
1800 | { | |
1801 | /* | |
1802 | * This -might- happen due to race conditions, but is unlikely. | |
1803 | * The scenario that leads to this happening is that the | |
1804 | * first of the pair of duplicate callbacks is queued, | |
1805 | * someone else starts a grace period that includes that | |
1806 | * callback, then the second of the pair must wait for the | |
1807 | * next grace period. Unlikely, but can happen. If it | |
1808 | * does happen, the debug-objects subsystem won't have splatted. | |
1809 | */ | |
1810 | pr_alert("rcutorture: duplicated callback was invoked.\n"); | |
1811 | } | |
1812 | #endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1813 | ||
1814 | /* | |
1815 | * Verify that double-free causes debug-objects to complain, but only | |
1816 | * if CONFIG_DEBUG_OBJECTS_RCU_HEAD=y. Otherwise, say that the test | |
1817 | * cannot be carried out. | |
1818 | */ | |
1819 | static void rcu_test_debug_objects(void) | |
1820 | { | |
1821 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD | |
1822 | struct rcu_head rh1; | |
1823 | struct rcu_head rh2; | |
1824 | ||
1825 | init_rcu_head_on_stack(&rh1); | |
1826 | init_rcu_head_on_stack(&rh2); | |
1827 | pr_alert("rcutorture: WARN: Duplicate call_rcu() test starting.\n"); | |
1828 | ||
1829 | /* Try to queue the rh2 pair of callbacks for the same grace period. */ | |
1830 | preempt_disable(); /* Prevent preemption from interrupting test. */ | |
1831 | rcu_read_lock(); /* Make it impossible to finish a grace period. */ | |
1832 | call_rcu(&rh1, rcu_torture_leak_cb); /* Start grace period. */ | |
1833 | local_irq_disable(); /* Make it harder to start a new grace period. */ | |
1834 | call_rcu(&rh2, rcu_torture_leak_cb); | |
1835 | call_rcu(&rh2, rcu_torture_err_cb); /* Duplicate callback. */ | |
1836 | local_irq_enable(); | |
1837 | rcu_read_unlock(); | |
1838 | preempt_enable(); | |
1839 | ||
1840 | /* Wait for them all to get done so we can safely return. */ | |
1841 | rcu_barrier(); | |
1842 | pr_alert("rcutorture: WARN: Duplicate call_rcu() test complete.\n"); | |
1843 | destroy_rcu_head_on_stack(&rh1); | |
1844 | destroy_rcu_head_on_stack(&rh2); | |
1845 | #else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1846 | pr_alert("rcutorture: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n"); | |
1847 | #endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
1848 | } | |
1849 | ||
6f8bc500 | 1850 | static int __init |
a241ec65 PM |
1851 | rcu_torture_init(void) |
1852 | { | |
1853 | int i; | |
1854 | int cpu; | |
1855 | int firsterr = 0; | |
fae4b54f | 1856 | int retval; |
2ec1f2d9 PM |
1857 | static struct rcu_torture_ops *torture_ops[] = { |
1858 | &rcu_ops, &rcu_bh_ops, &srcu_ops, &sched_ops, | |
1859 | }; | |
a241ec65 | 1860 | |
343e9099 PM |
1861 | mutex_lock(&fullstop_mutex); |
1862 | ||
a241ec65 | 1863 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1864 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1865 | cur_ops = torture_ops[i]; |
ade5fb81 | 1866 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1867 | break; |
72e9bb54 | 1868 | } |
ade5fb81 | 1869 | if (i == ARRAY_SIZE(torture_ops)) { |
2caa1e44 PM |
1870 | pr_alert("rcu-torture: invalid torture type: \"%s\"\n", |
1871 | torture_type); | |
1872 | pr_alert("rcu-torture types:"); | |
cf886c44 | 1873 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) |
2caa1e44 PM |
1874 | pr_alert(" %s", torture_ops[i]->name); |
1875 | pr_alert("\n"); | |
343e9099 | 1876 | mutex_unlock(&fullstop_mutex); |
a71fca58 | 1877 | return -EINVAL; |
72e9bb54 | 1878 | } |
bf66f18e | 1879 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
2caa1e44 | 1880 | pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); |
bf66f18e PM |
1881 | fqs_duration = 0; |
1882 | } | |
c8e5b163 | 1883 | if (cur_ops->init) |
72e9bb54 PM |
1884 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1885 | ||
a241ec65 PM |
1886 | if (nreaders >= 0) |
1887 | nrealreaders = nreaders; | |
1888 | else | |
1889 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1890 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
c9d557c1 | 1891 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1892 | |
1893 | /* Set up the freelist. */ | |
1894 | ||
1895 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1896 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1897 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1898 | list_add_tail(&rcu_tortures[i].rtort_free, |
1899 | &rcu_torture_freelist); | |
1900 | } | |
1901 | ||
1902 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1903 | ||
1904 | rcu_torture_current = NULL; | |
1905 | rcu_torture_current_version = 0; | |
1906 | atomic_set(&n_rcu_torture_alloc, 0); | |
1907 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1908 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1909 | atomic_set(&n_rcu_torture_mberror, 0); |
1910 | atomic_set(&n_rcu_torture_error, 0); | |
fae4b54f | 1911 | n_rcu_torture_barrier_error = 0; |
8e8be45e PM |
1912 | n_rcu_torture_boost_ktrerror = 0; |
1913 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
1914 | n_rcu_torture_boost_failure = 0; |
1915 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1916 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1917 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1918 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1919 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1920 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1921 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1922 | } | |
1923 | } | |
1924 | ||
1925 | /* Start up the kthreads. */ | |
1926 | ||
1927 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
60f53782 PM |
1928 | writer_task = kthread_create(rcu_torture_writer, NULL, |
1929 | "rcu_torture_writer"); | |
a241ec65 PM |
1930 | if (IS_ERR(writer_task)) { |
1931 | firsterr = PTR_ERR(writer_task); | |
1932 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
1933 | writer_task = NULL; | |
1934 | goto unwind; | |
1935 | } | |
60f53782 | 1936 | wake_up_process(writer_task); |
b772e1dd | 1937 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1938 | GFP_KERNEL); |
b772e1dd JT |
1939 | if (fakewriter_tasks == NULL) { |
1940 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1941 | firsterr = -ENOMEM; | |
1942 | goto unwind; | |
1943 | } | |
1944 | for (i = 0; i < nfakewriters; i++) { | |
1945 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
1946 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
a71fca58 | 1947 | "rcu_torture_fakewriter"); |
b772e1dd JT |
1948 | if (IS_ERR(fakewriter_tasks[i])) { |
1949 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
1950 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
1951 | fakewriter_tasks[i] = NULL; | |
1952 | goto unwind; | |
1953 | } | |
1954 | } | |
2860aaba | 1955 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1956 | GFP_KERNEL); |
1957 | if (reader_tasks == NULL) { | |
1958 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1959 | firsterr = -ENOMEM; | |
1960 | goto unwind; | |
1961 | } | |
1962 | for (i = 0; i < nrealreaders; i++) { | |
1963 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
1964 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
1965 | "rcu_torture_reader"); | |
1966 | if (IS_ERR(reader_tasks[i])) { | |
1967 | firsterr = PTR_ERR(reader_tasks[i]); | |
1968 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
1969 | reader_tasks[i] = NULL; | |
1970 | goto unwind; | |
1971 | } | |
1972 | } | |
1973 | if (stat_interval > 0) { | |
1974 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
1975 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
1976 | "rcu_torture_stats"); | |
1977 | if (IS_ERR(stats_task)) { | |
1978 | firsterr = PTR_ERR(stats_task); | |
1979 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
1980 | stats_task = NULL; | |
1981 | goto unwind; | |
1982 | } | |
1983 | } | |
d84f5203 SV |
1984 | if (test_no_idle_hz) { |
1985 | rcu_idle_cpu = num_online_cpus() - 1; | |
73d0a4b1 RR |
1986 | |
1987 | if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { | |
1988 | firsterr = -ENOMEM; | |
1989 | VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); | |
1990 | goto unwind; | |
1991 | } | |
1992 | ||
d84f5203 SV |
1993 | /* Create the shuffler thread */ |
1994 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
1995 | "rcu_torture_shuffle"); | |
1996 | if (IS_ERR(shuffler_task)) { | |
73d0a4b1 | 1997 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1998 | firsterr = PTR_ERR(shuffler_task); |
1999 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
2000 | shuffler_task = NULL; | |
2001 | goto unwind; | |
2002 | } | |
2003 | } | |
d120f65f PM |
2004 | if (stutter < 0) |
2005 | stutter = 0; | |
2006 | if (stutter) { | |
2007 | /* Create the stutter thread */ | |
2008 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
2009 | "rcu_torture_stutter"); | |
2010 | if (IS_ERR(stutter_task)) { | |
2011 | firsterr = PTR_ERR(stutter_task); | |
2012 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
2013 | stutter_task = NULL; | |
2014 | goto unwind; | |
2015 | } | |
2016 | } | |
bf66f18e PM |
2017 | if (fqs_duration < 0) |
2018 | fqs_duration = 0; | |
2019 | if (fqs_duration) { | |
2020 | /* Create the stutter thread */ | |
2021 | fqs_task = kthread_run(rcu_torture_fqs, NULL, | |
2022 | "rcu_torture_fqs"); | |
2023 | if (IS_ERR(fqs_task)) { | |
2024 | firsterr = PTR_ERR(fqs_task); | |
2025 | VERBOSE_PRINTK_ERRSTRING("Failed to create fqs"); | |
2026 | fqs_task = NULL; | |
2027 | goto unwind; | |
2028 | } | |
2029 | } | |
8e8be45e PM |
2030 | if (test_boost_interval < 1) |
2031 | test_boost_interval = 1; | |
2032 | if (test_boost_duration < 2) | |
2033 | test_boost_duration = 2; | |
2034 | if ((test_boost == 1 && cur_ops->can_boost) || | |
2035 | test_boost == 2) { | |
8e8be45e PM |
2036 | |
2037 | boost_starttime = jiffies + test_boost_interval * HZ; | |
2038 | register_cpu_notifier(&rcutorture_cpu_nb); | |
2039 | for_each_possible_cpu(i) { | |
2040 | if (cpu_is_offline(i)) | |
2041 | continue; /* Heuristic: CPU can go offline. */ | |
2042 | retval = rcutorture_booster_init(i); | |
2043 | if (retval < 0) { | |
2044 | firsterr = retval; | |
2045 | goto unwind; | |
2046 | } | |
2047 | } | |
2048 | } | |
d5f546d8 PM |
2049 | if (shutdown_secs > 0) { |
2050 | shutdown_time = jiffies + shutdown_secs * HZ; | |
60f53782 PM |
2051 | shutdown_task = kthread_create(rcu_torture_shutdown, NULL, |
2052 | "rcu_torture_shutdown"); | |
d5f546d8 PM |
2053 | if (IS_ERR(shutdown_task)) { |
2054 | firsterr = PTR_ERR(shutdown_task); | |
2055 | VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown"); | |
2056 | shutdown_task = NULL; | |
2057 | goto unwind; | |
2058 | } | |
60f53782 | 2059 | wake_up_process(shutdown_task); |
d5f546d8 | 2060 | } |
37e377d2 PM |
2061 | i = rcu_torture_onoff_init(); |
2062 | if (i != 0) { | |
2063 | firsterr = i; | |
2064 | goto unwind; | |
2065 | } | |
8e8be45e | 2066 | register_reboot_notifier(&rcutorture_shutdown_nb); |
37e377d2 PM |
2067 | i = rcu_torture_stall_init(); |
2068 | if (i != 0) { | |
2069 | firsterr = i; | |
2070 | goto unwind; | |
2071 | } | |
fae4b54f PM |
2072 | retval = rcu_torture_barrier_init(); |
2073 | if (retval != 0) { | |
2074 | firsterr = retval; | |
2075 | goto unwind; | |
2076 | } | |
d2818df1 PM |
2077 | if (object_debug) |
2078 | rcu_test_debug_objects(); | |
4a298656 | 2079 | rcutorture_record_test_transition(); |
343e9099 | 2080 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
2081 | return 0; |
2082 | ||
2083 | unwind: | |
343e9099 | 2084 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
2085 | rcu_torture_cleanup(); |
2086 | return firsterr; | |
2087 | } | |
2088 | ||
2089 | module_init(rcu_torture_init); | |
2090 | module_exit(rcu_torture_cleanup); |