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a241ec65 | 1 | /* |
29766f1e | 2 | * Read-Copy Update module-based torture test facility |
a241ec65 PM |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
b772e1dd | 18 | * Copyright (C) IBM Corporation, 2005, 2006 |
a241ec65 PM |
19 | * |
20 | * Authors: Paul E. McKenney <paulmck@us.ibm.com> | |
a71fca58 | 21 | * Josh Triplett <josh@freedesktop.org> |
a241ec65 PM |
22 | * |
23 | * See also: Documentation/RCU/torture.txt | |
24 | */ | |
25 | #include <linux/types.h> | |
26 | #include <linux/kernel.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/kthread.h> | |
30 | #include <linux/err.h> | |
31 | #include <linux/spinlock.h> | |
32 | #include <linux/smp.h> | |
33 | #include <linux/rcupdate.h> | |
34 | #include <linux/interrupt.h> | |
35 | #include <linux/sched.h> | |
36 | #include <asm/atomic.h> | |
37 | #include <linux/bitops.h> | |
a241ec65 PM |
38 | #include <linux/completion.h> |
39 | #include <linux/moduleparam.h> | |
40 | #include <linux/percpu.h> | |
41 | #include <linux/notifier.h> | |
343e9099 | 42 | #include <linux/reboot.h> |
83144186 | 43 | #include <linux/freezer.h> |
a241ec65 | 44 | #include <linux/cpu.h> |
a241ec65 | 45 | #include <linux/delay.h> |
a241ec65 | 46 | #include <linux/stat.h> |
b2896d2e | 47 | #include <linux/srcu.h> |
1aeb272c | 48 | #include <linux/slab.h> |
f07767fd | 49 | #include <asm/byteorder.h> |
8e8be45e | 50 | #include <linux/sched.h> |
a241ec65 PM |
51 | |
52 | MODULE_LICENSE("GPL"); | |
b772e1dd | 53 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and " |
a71fca58 | 54 | "Josh Triplett <josh@freedesktop.org>"); |
a241ec65 | 55 | |
4802211c | 56 | static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ |
b772e1dd | 57 | static int nfakewriters = 4; /* # fake writer threads */ |
d84f5203 | 58 | static int stat_interval; /* Interval between stats, in seconds. */ |
a241ec65 | 59 | /* Defaults to "only at end of test". */ |
d84f5203 SV |
60 | static int verbose; /* Print more debug info. */ |
61 | static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ | |
d120f65f PM |
62 | static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ |
63 | static int stutter = 5; /* Start/stop testing interval (in sec) */ | |
0729fbf3 | 64 | static int irqreader = 1; /* RCU readers from irq (timers). */ |
bf66f18e PM |
65 | static int fqs_duration = 0; /* Duration of bursts (us), 0 to disable. */ |
66 | static int fqs_holdoff = 0; /* Hold time within burst (us). */ | |
67 | static int fqs_stutter = 3; /* Wait time between bursts (s). */ | |
8e8be45e PM |
68 | static int test_boost = 1; /* Test RCU prio boost: 0=no, 1=maybe, 2=yes. */ |
69 | static int test_boost_interval = 7; /* Interval between boost tests, seconds. */ | |
70 | static int test_boost_duration = 4; /* Duration of each boost test, seconds. */ | |
20d2e428 | 71 | static char *torture_type = "rcu"; /* What RCU implementation to torture. */ |
a241ec65 | 72 | |
d6ad6711 | 73 | module_param(nreaders, int, 0444); |
a241ec65 | 74 | MODULE_PARM_DESC(nreaders, "Number of RCU reader threads"); |
d6ad6711 | 75 | module_param(nfakewriters, int, 0444); |
b772e1dd | 76 | MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads"); |
d6ad6711 | 77 | module_param(stat_interval, int, 0444); |
a241ec65 | 78 | MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s"); |
d6ad6711 | 79 | module_param(verbose, bool, 0444); |
a241ec65 | 80 | MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s"); |
d6ad6711 | 81 | module_param(test_no_idle_hz, bool, 0444); |
d84f5203 | 82 | MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs"); |
d6ad6711 | 83 | module_param(shuffle_interval, int, 0444); |
d84f5203 | 84 | MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles"); |
d120f65f PM |
85 | module_param(stutter, int, 0444); |
86 | MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test"); | |
0729fbf3 PM |
87 | module_param(irqreader, int, 0444); |
88 | MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers"); | |
bf66f18e PM |
89 | module_param(fqs_duration, int, 0444); |
90 | MODULE_PARM_DESC(fqs_duration, "Duration of fqs bursts (us)"); | |
91 | module_param(fqs_holdoff, int, 0444); | |
92 | MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)"); | |
93 | module_param(fqs_stutter, int, 0444); | |
94 | MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)"); | |
8e8be45e PM |
95 | module_param(test_boost, int, 0444); |
96 | MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); | |
97 | module_param(test_boost_interval, int, 0444); | |
98 | MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds."); | |
99 | module_param(test_boost_duration, int, 0444); | |
100 | MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds."); | |
d6ad6711 | 101 | module_param(torture_type, charp, 0444); |
b2896d2e | 102 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); |
72e9bb54 PM |
103 | |
104 | #define TORTURE_FLAG "-torture:" | |
a241ec65 | 105 | #define PRINTK_STRING(s) \ |
72e9bb54 | 106 | do { printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 107 | #define VERBOSE_PRINTK_STRING(s) \ |
72e9bb54 | 108 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 109 | #define VERBOSE_PRINTK_ERRSTRING(s) \ |
72e9bb54 | 110 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) |
a241ec65 PM |
111 | |
112 | static char printk_buf[4096]; | |
113 | ||
114 | static int nrealreaders; | |
115 | static struct task_struct *writer_task; | |
b772e1dd | 116 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
117 | static struct task_struct **reader_tasks; |
118 | static struct task_struct *stats_task; | |
d84f5203 | 119 | static struct task_struct *shuffler_task; |
d120f65f | 120 | static struct task_struct *stutter_task; |
bf66f18e | 121 | static struct task_struct *fqs_task; |
8e8be45e | 122 | static struct task_struct *boost_tasks[NR_CPUS]; |
a241ec65 PM |
123 | |
124 | #define RCU_TORTURE_PIPE_LEN 10 | |
125 | ||
126 | struct rcu_torture { | |
127 | struct rcu_head rtort_rcu; | |
128 | int rtort_pipe_count; | |
129 | struct list_head rtort_free; | |
996417d2 | 130 | int rtort_mbtest; |
a241ec65 PM |
131 | }; |
132 | ||
a241ec65 | 133 | static LIST_HEAD(rcu_torture_freelist); |
0ddea0ea | 134 | static struct rcu_torture __rcu *rcu_torture_current; |
a71fca58 | 135 | static long rcu_torture_current_version; |
a241ec65 PM |
136 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
137 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
138 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = | |
139 | { 0 }; | |
140 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = | |
141 | { 0 }; | |
142 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; | |
b2896d2e PM |
143 | static atomic_t n_rcu_torture_alloc; |
144 | static atomic_t n_rcu_torture_alloc_fail; | |
145 | static atomic_t n_rcu_torture_free; | |
146 | static atomic_t n_rcu_torture_mberror; | |
147 | static atomic_t n_rcu_torture_error; | |
8e8be45e PM |
148 | static long n_rcu_torture_boost_ktrerror; |
149 | static long n_rcu_torture_boost_rterror; | |
150 | static long n_rcu_torture_boost_allocerror; | |
151 | static long n_rcu_torture_boost_afferror; | |
152 | static long n_rcu_torture_boost_failure; | |
153 | static long n_rcu_torture_boosts; | |
a71fca58 | 154 | static long n_rcu_torture_timers; |
e3033736 | 155 | static struct list_head rcu_torture_removed; |
73d0a4b1 | 156 | static cpumask_var_t shuffle_tmp_mask; |
a241ec65 | 157 | |
a71fca58 | 158 | static int stutter_pause_test; |
d120f65f | 159 | |
31a72bce PM |
160 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
161 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
162 | #else | |
163 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
164 | #endif | |
165 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
166 | ||
8e8be45e PM |
167 | #ifdef CONFIG_RCU_BOOST |
168 | #define rcu_can_boost() 1 | |
169 | #else /* #ifdef CONFIG_RCU_BOOST */ | |
170 | #define rcu_can_boost() 0 | |
171 | #endif /* #else #ifdef CONFIG_RCU_BOOST */ | |
172 | ||
173 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ | |
174 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
175 | /* and boost task create/destroy. */ | |
176 | ||
c9d557c1 PM |
177 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
178 | ||
179 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
180 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
181 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
182 | static int fullstop = FULLSTOP_RMMOD; | |
0ddea0ea PM |
183 | /* |
184 | * Protect fullstop transitions and spawning of kthreads. | |
185 | */ | |
186 | static DEFINE_MUTEX(fullstop_mutex); | |
343e9099 PM |
187 | |
188 | /* | |
c9d557c1 | 189 | * Detect and respond to a system shutdown. |
343e9099 PM |
190 | */ |
191 | static int | |
192 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
193 | unsigned long unused2, void *unused3) | |
194 | { | |
c59ab97e | 195 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 196 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 197 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 PM |
198 | else |
199 | printk(KERN_WARNING /* but going down anyway, so... */ | |
200 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
c59ab97e | 201 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
202 | return NOTIFY_DONE; |
203 | } | |
204 | ||
c9d557c1 PM |
205 | /* |
206 | * Absorb kthreads into a kernel function that won't return, so that | |
207 | * they won't ever access module text or data again. | |
208 | */ | |
209 | static void rcutorture_shutdown_absorb(char *title) | |
210 | { | |
211 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
212 | printk(KERN_NOTICE | |
213 | "rcutorture thread %s parking due to system shutdown\n", | |
214 | title); | |
215 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
216 | } | |
217 | } | |
218 | ||
a241ec65 PM |
219 | /* |
220 | * Allocate an element from the rcu_tortures pool. | |
221 | */ | |
97a41e26 | 222 | static struct rcu_torture * |
a241ec65 PM |
223 | rcu_torture_alloc(void) |
224 | { | |
225 | struct list_head *p; | |
226 | ||
adac1665 | 227 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
228 | if (list_empty(&rcu_torture_freelist)) { |
229 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 230 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
231 | return NULL; |
232 | } | |
233 | atomic_inc(&n_rcu_torture_alloc); | |
234 | p = rcu_torture_freelist.next; | |
235 | list_del_init(p); | |
adac1665 | 236 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
237 | return container_of(p, struct rcu_torture, rtort_free); |
238 | } | |
239 | ||
240 | /* | |
241 | * Free an element to the rcu_tortures pool. | |
242 | */ | |
243 | static void | |
244 | rcu_torture_free(struct rcu_torture *p) | |
245 | { | |
246 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 247 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 248 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 249 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
250 | } |
251 | ||
a241ec65 PM |
252 | struct rcu_random_state { |
253 | unsigned long rrs_state; | |
75cfef32 | 254 | long rrs_count; |
a241ec65 PM |
255 | }; |
256 | ||
257 | #define RCU_RANDOM_MULT 39916801 /* prime */ | |
258 | #define RCU_RANDOM_ADD 479001701 /* prime */ | |
259 | #define RCU_RANDOM_REFRESH 10000 | |
260 | ||
261 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } | |
262 | ||
263 | /* | |
264 | * Crude but fast random-number generator. Uses a linear congruential | |
c17ac855 | 265 | * generator, with occasional help from cpu_clock(). |
a241ec65 | 266 | */ |
75cfef32 | 267 | static unsigned long |
a241ec65 PM |
268 | rcu_random(struct rcu_random_state *rrsp) |
269 | { | |
a241ec65 | 270 | if (--rrsp->rrs_count < 0) { |
c676329a | 271 | rrsp->rrs_state += (unsigned long)local_clock(); |
a241ec65 PM |
272 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
273 | } | |
274 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; | |
275 | return swahw32(rrsp->rrs_state); | |
276 | } | |
277 | ||
d120f65f | 278 | static void |
c9d557c1 | 279 | rcu_stutter_wait(char *title) |
d120f65f | 280 | { |
c9d557c1 | 281 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
282 | if (rcutorture_runnable) |
283 | schedule_timeout_interruptible(1); | |
284 | else | |
3ccf79f4 | 285 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 286 | rcutorture_shutdown_absorb(title); |
343e9099 | 287 | } |
d120f65f PM |
288 | } |
289 | ||
72e9bb54 PM |
290 | /* |
291 | * Operations vector for selecting different types of tests. | |
292 | */ | |
293 | ||
294 | struct rcu_torture_ops { | |
295 | void (*init)(void); | |
296 | void (*cleanup)(void); | |
297 | int (*readlock)(void); | |
0acc512c | 298 | void (*read_delay)(struct rcu_random_state *rrsp); |
72e9bb54 PM |
299 | void (*readunlock)(int idx); |
300 | int (*completed)(void); | |
0acc512c | 301 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 302 | void (*sync)(void); |
2326974d | 303 | void (*cb_barrier)(void); |
bf66f18e | 304 | void (*fqs)(void); |
72e9bb54 | 305 | int (*stats)(char *page); |
0acc512c | 306 | int irq_capable; |
8e8be45e | 307 | int can_boost; |
72e9bb54 PM |
308 | char *name; |
309 | }; | |
a71fca58 PM |
310 | |
311 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
312 | |
313 | /* | |
314 | * Definitions for rcu torture testing. | |
315 | */ | |
316 | ||
a49a4af7 | 317 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
318 | { |
319 | rcu_read_lock(); | |
320 | return 0; | |
321 | } | |
322 | ||
b2896d2e PM |
323 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
324 | { | |
b8d57a76 JT |
325 | const unsigned long shortdelay_us = 200; |
326 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 327 | |
b8d57a76 JT |
328 | /* We want a short delay sometimes to make a reader delay the grace |
329 | * period, and we want a long delay occasionally to trigger | |
330 | * force_quiescent_state. */ | |
b2896d2e | 331 | |
b8d57a76 JT |
332 | if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
333 | mdelay(longdelay_ms); | |
334 | if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) | |
335 | udelay(shortdelay_us); | |
e546f485 LJ |
336 | #ifdef CONFIG_PREEMPT |
337 | if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000))) | |
338 | preempt_schedule(); /* No QS if preempt_disable() in effect */ | |
339 | #endif | |
b2896d2e PM |
340 | } |
341 | ||
a49a4af7 | 342 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
343 | { |
344 | rcu_read_unlock(); | |
345 | } | |
346 | ||
347 | static int rcu_torture_completed(void) | |
348 | { | |
349 | return rcu_batches_completed(); | |
350 | } | |
351 | ||
352 | static void | |
353 | rcu_torture_cb(struct rcu_head *p) | |
354 | { | |
355 | int i; | |
356 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
357 | ||
c9d557c1 | 358 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
359 | /* Test is ending, just drop callbacks on the floor. */ |
360 | /* The next initialization will pick up the pieces. */ | |
361 | return; | |
362 | } | |
363 | i = rp->rtort_pipe_count; | |
364 | if (i > RCU_TORTURE_PIPE_LEN) | |
365 | i = RCU_TORTURE_PIPE_LEN; | |
366 | atomic_inc(&rcu_torture_wcount[i]); | |
367 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
368 | rp->rtort_mbtest = 0; | |
369 | rcu_torture_free(rp); | |
370 | } else | |
0acc512c | 371 | cur_ops->deferred_free(rp); |
72e9bb54 PM |
372 | } |
373 | ||
d9a3da06 PM |
374 | static int rcu_no_completed(void) |
375 | { | |
376 | return 0; | |
377 | } | |
378 | ||
72e9bb54 PM |
379 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
380 | { | |
381 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
382 | } | |
383 | ||
384 | static struct rcu_torture_ops rcu_ops = { | |
0acc512c PM |
385 | .init = NULL, |
386 | .cleanup = NULL, | |
387 | .readlock = rcu_torture_read_lock, | |
388 | .read_delay = rcu_read_delay, | |
389 | .readunlock = rcu_torture_read_unlock, | |
390 | .completed = rcu_torture_completed, | |
391 | .deferred_free = rcu_torture_deferred_free, | |
392 | .sync = synchronize_rcu, | |
393 | .cb_barrier = rcu_barrier, | |
bf66f18e | 394 | .fqs = rcu_force_quiescent_state, |
0acc512c | 395 | .stats = NULL, |
a71fca58 | 396 | .irq_capable = 1, |
8e8be45e | 397 | .can_boost = rcu_can_boost(), |
a71fca58 | 398 | .name = "rcu" |
72e9bb54 PM |
399 | }; |
400 | ||
e3033736 JT |
401 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
402 | { | |
403 | int i; | |
404 | struct rcu_torture *rp; | |
405 | struct rcu_torture *rp1; | |
406 | ||
407 | cur_ops->sync(); | |
408 | list_add(&p->rtort_free, &rcu_torture_removed); | |
409 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
410 | i = rp->rtort_pipe_count; | |
411 | if (i > RCU_TORTURE_PIPE_LEN) | |
412 | i = RCU_TORTURE_PIPE_LEN; | |
413 | atomic_inc(&rcu_torture_wcount[i]); | |
414 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
415 | rp->rtort_mbtest = 0; | |
416 | list_del(&rp->rtort_free); | |
417 | rcu_torture_free(rp); | |
418 | } | |
419 | } | |
420 | } | |
421 | ||
422 | static void rcu_sync_torture_init(void) | |
423 | { | |
424 | INIT_LIST_HEAD(&rcu_torture_removed); | |
425 | } | |
426 | ||
20d2e428 | 427 | static struct rcu_torture_ops rcu_sync_ops = { |
0acc512c PM |
428 | .init = rcu_sync_torture_init, |
429 | .cleanup = NULL, | |
430 | .readlock = rcu_torture_read_lock, | |
431 | .read_delay = rcu_read_delay, | |
432 | .readunlock = rcu_torture_read_unlock, | |
433 | .completed = rcu_torture_completed, | |
434 | .deferred_free = rcu_sync_torture_deferred_free, | |
435 | .sync = synchronize_rcu, | |
436 | .cb_barrier = NULL, | |
bf66f18e | 437 | .fqs = rcu_force_quiescent_state, |
0acc512c PM |
438 | .stats = NULL, |
439 | .irq_capable = 1, | |
8e8be45e | 440 | .can_boost = rcu_can_boost(), |
0acc512c | 441 | .name = "rcu_sync" |
20d2e428 JT |
442 | }; |
443 | ||
d9a3da06 PM |
444 | static struct rcu_torture_ops rcu_expedited_ops = { |
445 | .init = rcu_sync_torture_init, | |
446 | .cleanup = NULL, | |
447 | .readlock = rcu_torture_read_lock, | |
448 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
449 | .readunlock = rcu_torture_read_unlock, | |
450 | .completed = rcu_no_completed, | |
451 | .deferred_free = rcu_sync_torture_deferred_free, | |
452 | .sync = synchronize_rcu_expedited, | |
453 | .cb_barrier = NULL, | |
bf66f18e | 454 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
455 | .stats = NULL, |
456 | .irq_capable = 1, | |
8e8be45e | 457 | .can_boost = rcu_can_boost(), |
d9a3da06 PM |
458 | .name = "rcu_expedited" |
459 | }; | |
460 | ||
c32e0660 PM |
461 | /* |
462 | * Definitions for rcu_bh torture testing. | |
463 | */ | |
464 | ||
a49a4af7 | 465 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
466 | { |
467 | rcu_read_lock_bh(); | |
468 | return 0; | |
469 | } | |
470 | ||
a49a4af7 | 471 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
472 | { |
473 | rcu_read_unlock_bh(); | |
474 | } | |
475 | ||
476 | static int rcu_bh_torture_completed(void) | |
477 | { | |
478 | return rcu_batches_completed_bh(); | |
479 | } | |
480 | ||
481 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
482 | { | |
483 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
484 | } | |
485 | ||
b772e1dd JT |
486 | struct rcu_bh_torture_synchronize { |
487 | struct rcu_head head; | |
488 | struct completion completion; | |
489 | }; | |
490 | ||
491 | static void rcu_bh_torture_wakeme_after_cb(struct rcu_head *head) | |
492 | { | |
493 | struct rcu_bh_torture_synchronize *rcu; | |
494 | ||
495 | rcu = container_of(head, struct rcu_bh_torture_synchronize, head); | |
496 | complete(&rcu->completion); | |
497 | } | |
498 | ||
499 | static void rcu_bh_torture_synchronize(void) | |
500 | { | |
501 | struct rcu_bh_torture_synchronize rcu; | |
502 | ||
72d5a9f7 | 503 | init_rcu_head_on_stack(&rcu.head); |
b772e1dd JT |
504 | init_completion(&rcu.completion); |
505 | call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb); | |
506 | wait_for_completion(&rcu.completion); | |
72d5a9f7 | 507 | destroy_rcu_head_on_stack(&rcu.head); |
b772e1dd JT |
508 | } |
509 | ||
c32e0660 | 510 | static struct rcu_torture_ops rcu_bh_ops = { |
0acc512c PM |
511 | .init = NULL, |
512 | .cleanup = NULL, | |
513 | .readlock = rcu_bh_torture_read_lock, | |
514 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
515 | .readunlock = rcu_bh_torture_read_unlock, | |
516 | .completed = rcu_bh_torture_completed, | |
517 | .deferred_free = rcu_bh_torture_deferred_free, | |
518 | .sync = rcu_bh_torture_synchronize, | |
519 | .cb_barrier = rcu_barrier_bh, | |
bf66f18e | 520 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
521 | .stats = NULL, |
522 | .irq_capable = 1, | |
523 | .name = "rcu_bh" | |
c32e0660 PM |
524 | }; |
525 | ||
11a14701 | 526 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
0acc512c PM |
527 | .init = rcu_sync_torture_init, |
528 | .cleanup = NULL, | |
529 | .readlock = rcu_bh_torture_read_lock, | |
530 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
531 | .readunlock = rcu_bh_torture_read_unlock, | |
532 | .completed = rcu_bh_torture_completed, | |
533 | .deferred_free = rcu_sync_torture_deferred_free, | |
534 | .sync = rcu_bh_torture_synchronize, | |
535 | .cb_barrier = NULL, | |
bf66f18e | 536 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
537 | .stats = NULL, |
538 | .irq_capable = 1, | |
539 | .name = "rcu_bh_sync" | |
11a14701 JT |
540 | }; |
541 | ||
b2896d2e PM |
542 | /* |
543 | * Definitions for srcu torture testing. | |
544 | */ | |
545 | ||
546 | static struct srcu_struct srcu_ctl; | |
b2896d2e PM |
547 | |
548 | static void srcu_torture_init(void) | |
549 | { | |
550 | init_srcu_struct(&srcu_ctl); | |
e3033736 | 551 | rcu_sync_torture_init(); |
b2896d2e PM |
552 | } |
553 | ||
554 | static void srcu_torture_cleanup(void) | |
555 | { | |
556 | synchronize_srcu(&srcu_ctl); | |
557 | cleanup_srcu_struct(&srcu_ctl); | |
558 | } | |
559 | ||
012d3ca8 | 560 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
561 | { |
562 | return srcu_read_lock(&srcu_ctl); | |
563 | } | |
564 | ||
565 | static void srcu_read_delay(struct rcu_random_state *rrsp) | |
566 | { | |
567 | long delay; | |
568 | const long uspertick = 1000000 / HZ; | |
569 | const long longdelay = 10; | |
570 | ||
571 | /* We want there to be long-running readers, but not all the time. */ | |
572 | ||
573 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); | |
574 | if (!delay) | |
575 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
576 | else |
577 | rcu_read_delay(rrsp); | |
b2896d2e PM |
578 | } |
579 | ||
012d3ca8 | 580 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
581 | { |
582 | srcu_read_unlock(&srcu_ctl, idx); | |
583 | } | |
584 | ||
585 | static int srcu_torture_completed(void) | |
586 | { | |
587 | return srcu_batches_completed(&srcu_ctl); | |
588 | } | |
589 | ||
b772e1dd JT |
590 | static void srcu_torture_synchronize(void) |
591 | { | |
592 | synchronize_srcu(&srcu_ctl); | |
593 | } | |
594 | ||
b2896d2e PM |
595 | static int srcu_torture_stats(char *page) |
596 | { | |
597 | int cnt = 0; | |
598 | int cpu; | |
599 | int idx = srcu_ctl.completed & 0x1; | |
600 | ||
601 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", | |
602 | torture_type, TORTURE_FLAG, idx); | |
603 | for_each_possible_cpu(cpu) { | |
604 | cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu, | |
605 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], | |
606 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
607 | } | |
608 | cnt += sprintf(&page[cnt], "\n"); | |
609 | return cnt; | |
610 | } | |
611 | ||
612 | static struct rcu_torture_ops srcu_ops = { | |
0acc512c PM |
613 | .init = srcu_torture_init, |
614 | .cleanup = srcu_torture_cleanup, | |
615 | .readlock = srcu_torture_read_lock, | |
616 | .read_delay = srcu_read_delay, | |
617 | .readunlock = srcu_torture_read_unlock, | |
618 | .completed = srcu_torture_completed, | |
619 | .deferred_free = rcu_sync_torture_deferred_free, | |
620 | .sync = srcu_torture_synchronize, | |
621 | .cb_barrier = NULL, | |
622 | .stats = srcu_torture_stats, | |
623 | .name = "srcu" | |
b2896d2e PM |
624 | }; |
625 | ||
804bb837 PM |
626 | static void srcu_torture_synchronize_expedited(void) |
627 | { | |
628 | synchronize_srcu_expedited(&srcu_ctl); | |
629 | } | |
630 | ||
631 | static struct rcu_torture_ops srcu_expedited_ops = { | |
632 | .init = srcu_torture_init, | |
633 | .cleanup = srcu_torture_cleanup, | |
634 | .readlock = srcu_torture_read_lock, | |
635 | .read_delay = srcu_read_delay, | |
636 | .readunlock = srcu_torture_read_unlock, | |
637 | .completed = srcu_torture_completed, | |
638 | .deferred_free = rcu_sync_torture_deferred_free, | |
639 | .sync = srcu_torture_synchronize_expedited, | |
640 | .cb_barrier = NULL, | |
641 | .stats = srcu_torture_stats, | |
642 | .name = "srcu_expedited" | |
643 | }; | |
644 | ||
4b6c2cca JT |
645 | /* |
646 | * Definitions for sched torture testing. | |
647 | */ | |
648 | ||
649 | static int sched_torture_read_lock(void) | |
650 | { | |
651 | preempt_disable(); | |
652 | return 0; | |
653 | } | |
654 | ||
655 | static void sched_torture_read_unlock(int idx) | |
656 | { | |
657 | preempt_enable(); | |
658 | } | |
659 | ||
2326974d PM |
660 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
661 | { | |
662 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
663 | } | |
664 | ||
4b6c2cca JT |
665 | static void sched_torture_synchronize(void) |
666 | { | |
667 | synchronize_sched(); | |
668 | } | |
669 | ||
670 | static struct rcu_torture_ops sched_ops = { | |
0acc512c PM |
671 | .init = rcu_sync_torture_init, |
672 | .cleanup = NULL, | |
673 | .readlock = sched_torture_read_lock, | |
674 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
675 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 676 | .completed = rcu_no_completed, |
0acc512c PM |
677 | .deferred_free = rcu_sched_torture_deferred_free, |
678 | .sync = sched_torture_synchronize, | |
679 | .cb_barrier = rcu_barrier_sched, | |
bf66f18e | 680 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
681 | .stats = NULL, |
682 | .irq_capable = 1, | |
683 | .name = "sched" | |
4b6c2cca JT |
684 | }; |
685 | ||
804bb837 | 686 | static struct rcu_torture_ops sched_sync_ops = { |
0acc512c PM |
687 | .init = rcu_sync_torture_init, |
688 | .cleanup = NULL, | |
689 | .readlock = sched_torture_read_lock, | |
690 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
691 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 692 | .completed = rcu_no_completed, |
0acc512c PM |
693 | .deferred_free = rcu_sync_torture_deferred_free, |
694 | .sync = sched_torture_synchronize, | |
695 | .cb_barrier = NULL, | |
bf66f18e | 696 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
697 | .stats = NULL, |
698 | .name = "sched_sync" | |
699 | }; | |
700 | ||
0acc512c PM |
701 | static struct rcu_torture_ops sched_expedited_ops = { |
702 | .init = rcu_sync_torture_init, | |
703 | .cleanup = NULL, | |
704 | .readlock = sched_torture_read_lock, | |
705 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
706 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 707 | .completed = rcu_no_completed, |
0acc512c PM |
708 | .deferred_free = rcu_sync_torture_deferred_free, |
709 | .sync = synchronize_sched_expedited, | |
710 | .cb_barrier = NULL, | |
bf66f18e | 711 | .fqs = rcu_sched_force_quiescent_state, |
969c7921 | 712 | .stats = NULL, |
0acc512c PM |
713 | .irq_capable = 1, |
714 | .name = "sched_expedited" | |
2326974d PM |
715 | }; |
716 | ||
8e8be45e PM |
717 | /* |
718 | * RCU torture priority-boost testing. Runs one real-time thread per | |
719 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
720 | * spinning waiting for them to be invoked. If a given callback takes | |
721 | * too long to be invoked, we assume that priority inversion has occurred. | |
722 | */ | |
723 | ||
724 | struct rcu_boost_inflight { | |
725 | struct rcu_head rcu; | |
726 | int inflight; | |
727 | }; | |
728 | ||
729 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
730 | { | |
731 | struct rcu_boost_inflight *rbip = | |
732 | container_of(head, struct rcu_boost_inflight, rcu); | |
733 | ||
734 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
735 | rbip->inflight = 0; | |
736 | } | |
737 | ||
738 | static int rcu_torture_boost(void *arg) | |
739 | { | |
740 | unsigned long call_rcu_time; | |
741 | unsigned long endtime; | |
742 | unsigned long oldstarttime; | |
743 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
744 | struct sched_param sp; | |
745 | ||
746 | VERBOSE_PRINTK_STRING("rcu_torture_boost started"); | |
747 | ||
748 | /* Set real-time priority. */ | |
749 | sp.sched_priority = 1; | |
750 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
751 | VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!"); | |
752 | n_rcu_torture_boost_rterror++; | |
753 | } | |
754 | ||
755 | /* Each pass through the following loop does one boost-test cycle. */ | |
756 | do { | |
757 | /* Wait for the next test interval. */ | |
758 | oldstarttime = boost_starttime; | |
759 | while (jiffies - oldstarttime > ULONG_MAX / 2) { | |
760 | schedule_timeout_uninterruptible(1); | |
761 | rcu_stutter_wait("rcu_torture_boost"); | |
762 | if (kthread_should_stop() || | |
763 | fullstop != FULLSTOP_DONTSTOP) | |
764 | goto checkwait; | |
765 | } | |
766 | ||
767 | /* Do one boost-test interval. */ | |
768 | endtime = oldstarttime + test_boost_duration * HZ; | |
769 | call_rcu_time = jiffies; | |
770 | while (jiffies - endtime > ULONG_MAX / 2) { | |
771 | /* If we don't have a callback in flight, post one. */ | |
772 | if (!rbi.inflight) { | |
773 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
774 | rbi.inflight = 1; | |
775 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
776 | if (jiffies - call_rcu_time > | |
777 | test_boost_duration * HZ - HZ / 2) { | |
778 | VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed"); | |
779 | n_rcu_torture_boost_failure++; | |
780 | } | |
781 | call_rcu_time = jiffies; | |
782 | } | |
783 | cond_resched(); | |
784 | rcu_stutter_wait("rcu_torture_boost"); | |
785 | if (kthread_should_stop() || | |
786 | fullstop != FULLSTOP_DONTSTOP) | |
787 | goto checkwait; | |
788 | } | |
789 | ||
790 | /* | |
791 | * Set the start time of the next test interval. | |
792 | * Yes, this is vulnerable to long delays, but such | |
793 | * delays simply cause a false negative for the next | |
794 | * interval. Besides, we are running at RT priority, | |
795 | * so delays should be relatively rare. | |
796 | */ | |
797 | while (oldstarttime == boost_starttime) { | |
798 | if (mutex_trylock(&boost_mutex)) { | |
799 | boost_starttime = jiffies + | |
800 | test_boost_interval * HZ; | |
801 | n_rcu_torture_boosts++; | |
802 | mutex_unlock(&boost_mutex); | |
803 | break; | |
804 | } | |
805 | schedule_timeout_uninterruptible(1); | |
806 | } | |
807 | ||
808 | /* Go do the stutter. */ | |
809 | checkwait: rcu_stutter_wait("rcu_torture_boost"); | |
810 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
811 | ||
812 | /* Clean up and exit. */ | |
813 | VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping"); | |
814 | rcutorture_shutdown_absorb("rcu_torture_boost"); | |
815 | while (!kthread_should_stop() || rbi.inflight) | |
816 | schedule_timeout_uninterruptible(1); | |
817 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ | |
818 | return 0; | |
819 | } | |
820 | ||
bf66f18e PM |
821 | /* |
822 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
823 | * bursts of calls to force_quiescent_state(), increasing the probability | |
824 | * of occurrence of some important types of race conditions. | |
825 | */ | |
826 | static int | |
827 | rcu_torture_fqs(void *arg) | |
828 | { | |
829 | unsigned long fqs_resume_time; | |
830 | int fqs_burst_remaining; | |
831 | ||
832 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task started"); | |
833 | do { | |
834 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
835 | while (jiffies - fqs_resume_time > LONG_MAX) { | |
836 | schedule_timeout_interruptible(1); | |
837 | } | |
838 | fqs_burst_remaining = fqs_duration; | |
839 | while (fqs_burst_remaining > 0) { | |
840 | cur_ops->fqs(); | |
841 | udelay(fqs_holdoff); | |
842 | fqs_burst_remaining -= fqs_holdoff; | |
843 | } | |
844 | rcu_stutter_wait("rcu_torture_fqs"); | |
845 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
846 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping"); | |
847 | rcutorture_shutdown_absorb("rcu_torture_fqs"); | |
848 | while (!kthread_should_stop()) | |
849 | schedule_timeout_uninterruptible(1); | |
850 | return 0; | |
851 | } | |
852 | ||
a241ec65 PM |
853 | /* |
854 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
855 | * for that pointed to by rcu_torture_current, freeing the old structure | |
856 | * after a series of grace periods (the "pipeline"). | |
857 | */ | |
858 | static int | |
859 | rcu_torture_writer(void *arg) | |
860 | { | |
861 | int i; | |
862 | long oldbatch = rcu_batches_completed(); | |
863 | struct rcu_torture *rp; | |
864 | struct rcu_torture *old_rp; | |
865 | static DEFINE_RCU_RANDOM(rand); | |
866 | ||
867 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
868 | set_user_nice(current, 19); |
869 | ||
a241ec65 PM |
870 | do { |
871 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
872 | rp = rcu_torture_alloc(); |
873 | if (rp == NULL) | |
a241ec65 PM |
874 | continue; |
875 | rp->rtort_pipe_count = 0; | |
876 | udelay(rcu_random(&rand) & 0x3ff); | |
0ddea0ea PM |
877 | old_rp = rcu_dereference_check(rcu_torture_current, |
878 | current == writer_task); | |
996417d2 | 879 | rp->rtort_mbtest = 1; |
a241ec65 | 880 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 881 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 882 | if (old_rp) { |
a241ec65 PM |
883 | i = old_rp->rtort_pipe_count; |
884 | if (i > RCU_TORTURE_PIPE_LEN) | |
885 | i = RCU_TORTURE_PIPE_LEN; | |
886 | atomic_inc(&rcu_torture_wcount[i]); | |
887 | old_rp->rtort_pipe_count++; | |
0acc512c | 888 | cur_ops->deferred_free(old_rp); |
a241ec65 PM |
889 | } |
890 | rcu_torture_current_version++; | |
72e9bb54 | 891 | oldbatch = cur_ops->completed(); |
c9d557c1 PM |
892 | rcu_stutter_wait("rcu_torture_writer"); |
893 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 894 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
895 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
896 | while (!kthread_should_stop()) | |
a241ec65 PM |
897 | schedule_timeout_uninterruptible(1); |
898 | return 0; | |
899 | } | |
900 | ||
b772e1dd JT |
901 | /* |
902 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
903 | * delay between calls. | |
904 | */ | |
905 | static int | |
906 | rcu_torture_fakewriter(void *arg) | |
907 | { | |
908 | DEFINE_RCU_RANDOM(rand); | |
909 | ||
910 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
911 | set_user_nice(current, 19); | |
912 | ||
913 | do { | |
914 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); | |
915 | udelay(rcu_random(&rand) & 0x3ff); | |
916 | cur_ops->sync(); | |
c9d557c1 PM |
917 | rcu_stutter_wait("rcu_torture_fakewriter"); |
918 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
919 | |
920 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
921 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
922 | while (!kthread_should_stop()) | |
b772e1dd JT |
923 | schedule_timeout_uninterruptible(1); |
924 | return 0; | |
925 | } | |
926 | ||
0729fbf3 PM |
927 | /* |
928 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
929 | * incrementing the corresponding element of the pipeline array. The | |
930 | * counter in the element should never be greater than 1, otherwise, the | |
931 | * RCU implementation is broken. | |
932 | */ | |
933 | static void rcu_torture_timer(unsigned long unused) | |
934 | { | |
935 | int idx; | |
936 | int completed; | |
937 | static DEFINE_RCU_RANDOM(rand); | |
938 | static DEFINE_SPINLOCK(rand_lock); | |
939 | struct rcu_torture *p; | |
940 | int pipe_count; | |
941 | ||
942 | idx = cur_ops->readlock(); | |
943 | completed = cur_ops->completed(); | |
632ee200 PM |
944 | p = rcu_dereference_check(rcu_torture_current, |
945 | rcu_read_lock_held() || | |
946 | rcu_read_lock_bh_held() || | |
947 | rcu_read_lock_sched_held() || | |
948 | srcu_read_lock_held(&srcu_ctl)); | |
0729fbf3 PM |
949 | if (p == NULL) { |
950 | /* Leave because rcu_torture_writer is not yet underway */ | |
951 | cur_ops->readunlock(idx); | |
952 | return; | |
953 | } | |
954 | if (p->rtort_mbtest == 0) | |
955 | atomic_inc(&n_rcu_torture_mberror); | |
956 | spin_lock(&rand_lock); | |
0acc512c | 957 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
958 | n_rcu_torture_timers++; |
959 | spin_unlock(&rand_lock); | |
960 | preempt_disable(); | |
961 | pipe_count = p->rtort_pipe_count; | |
962 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
963 | /* Should not happen, but... */ | |
964 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
965 | } | |
dd17c8f7 | 966 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
0729fbf3 PM |
967 | completed = cur_ops->completed() - completed; |
968 | if (completed > RCU_TORTURE_PIPE_LEN) { | |
969 | /* Should not happen, but... */ | |
970 | completed = RCU_TORTURE_PIPE_LEN; | |
971 | } | |
dd17c8f7 | 972 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
973 | preempt_enable(); |
974 | cur_ops->readunlock(idx); | |
975 | } | |
976 | ||
a241ec65 PM |
977 | /* |
978 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
979 | * incrementing the corresponding element of the pipeline array. The | |
980 | * counter in the element should never be greater than 1, otherwise, the | |
981 | * RCU implementation is broken. | |
982 | */ | |
983 | static int | |
984 | rcu_torture_reader(void *arg) | |
985 | { | |
986 | int completed; | |
72e9bb54 | 987 | int idx; |
a241ec65 PM |
988 | DEFINE_RCU_RANDOM(rand); |
989 | struct rcu_torture *p; | |
990 | int pipe_count; | |
0729fbf3 | 991 | struct timer_list t; |
a241ec65 PM |
992 | |
993 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 994 | set_user_nice(current, 19); |
0acc512c | 995 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 996 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 997 | |
a241ec65 | 998 | do { |
0acc512c | 999 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 1000 | if (!timer_pending(&t)) |
6155fec9 | 1001 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 1002 | } |
72e9bb54 PM |
1003 | idx = cur_ops->readlock(); |
1004 | completed = cur_ops->completed(); | |
632ee200 PM |
1005 | p = rcu_dereference_check(rcu_torture_current, |
1006 | rcu_read_lock_held() || | |
1007 | rcu_read_lock_bh_held() || | |
1008 | rcu_read_lock_sched_held() || | |
1009 | srcu_read_lock_held(&srcu_ctl)); | |
a241ec65 PM |
1010 | if (p == NULL) { |
1011 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 1012 | cur_ops->readunlock(idx); |
a241ec65 PM |
1013 | schedule_timeout_interruptible(HZ); |
1014 | continue; | |
1015 | } | |
996417d2 PM |
1016 | if (p->rtort_mbtest == 0) |
1017 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 1018 | cur_ops->read_delay(&rand); |
a241ec65 PM |
1019 | preempt_disable(); |
1020 | pipe_count = p->rtort_pipe_count; | |
1021 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
1022 | /* Should not happen, but... */ | |
1023 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
1024 | } | |
dd17c8f7 | 1025 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
72e9bb54 | 1026 | completed = cur_ops->completed() - completed; |
a241ec65 PM |
1027 | if (completed > RCU_TORTURE_PIPE_LEN) { |
1028 | /* Should not happen, but... */ | |
1029 | completed = RCU_TORTURE_PIPE_LEN; | |
1030 | } | |
dd17c8f7 | 1031 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 1032 | preempt_enable(); |
72e9bb54 | 1033 | cur_ops->readunlock(idx); |
a241ec65 | 1034 | schedule(); |
c9d557c1 PM |
1035 | rcu_stutter_wait("rcu_torture_reader"); |
1036 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 1037 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 1038 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0acc512c | 1039 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1040 | del_timer_sync(&t); |
c9d557c1 | 1041 | while (!kthread_should_stop()) |
a241ec65 PM |
1042 | schedule_timeout_uninterruptible(1); |
1043 | return 0; | |
1044 | } | |
1045 | ||
1046 | /* | |
1047 | * Create an RCU-torture statistics message in the specified buffer. | |
1048 | */ | |
1049 | static int | |
1050 | rcu_torture_printk(char *page) | |
1051 | { | |
1052 | int cnt = 0; | |
1053 | int cpu; | |
1054 | int i; | |
1055 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1056 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1057 | ||
0a945022 | 1058 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1059 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1060 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
1061 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
1062 | } | |
1063 | } | |
1064 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
1065 | if (pipesummary[i] != 0) | |
1066 | break; | |
1067 | } | |
72e9bb54 | 1068 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1069 | cnt += sprintf(&page[cnt], |
996417d2 | 1070 | "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d " |
8e8be45e PM |
1071 | "rtmbe: %d rtbke: %ld rtbre: %ld rtbae: %ld rtbafe: %ld " |
1072 | "rtbf: %ld rtb: %ld nt: %ld", | |
a241ec65 PM |
1073 | rcu_torture_current, |
1074 | rcu_torture_current_version, | |
1075 | list_empty(&rcu_torture_freelist), | |
1076 | atomic_read(&n_rcu_torture_alloc), | |
1077 | atomic_read(&n_rcu_torture_alloc_fail), | |
996417d2 | 1078 | atomic_read(&n_rcu_torture_free), |
0729fbf3 | 1079 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e PM |
1080 | n_rcu_torture_boost_ktrerror, |
1081 | n_rcu_torture_boost_rterror, | |
1082 | n_rcu_torture_boost_allocerror, | |
1083 | n_rcu_torture_boost_afferror, | |
1084 | n_rcu_torture_boost_failure, | |
1085 | n_rcu_torture_boosts, | |
0729fbf3 | 1086 | n_rcu_torture_timers); |
8e8be45e PM |
1087 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
1088 | n_rcu_torture_boost_ktrerror != 0 || | |
1089 | n_rcu_torture_boost_rterror != 0 || | |
1090 | n_rcu_torture_boost_allocerror != 0 || | |
1091 | n_rcu_torture_boost_afferror != 0 || | |
1092 | n_rcu_torture_boost_failure != 0) | |
996417d2 | 1093 | cnt += sprintf(&page[cnt], " !!!"); |
72e9bb54 | 1094 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
996417d2 | 1095 | if (i > 1) { |
a241ec65 | 1096 | cnt += sprintf(&page[cnt], "!!! "); |
996417d2 | 1097 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 1098 | WARN_ON_ONCE(1); |
996417d2 | 1099 | } |
a241ec65 PM |
1100 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
1101 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) | |
1102 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); | |
72e9bb54 | 1103 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1104 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
72e9bb54 | 1105 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
a241ec65 | 1106 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
72e9bb54 | 1107 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 PM |
1108 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
1109 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { | |
1110 | cnt += sprintf(&page[cnt], " %d", | |
1111 | atomic_read(&rcu_torture_wcount[i])); | |
1112 | } | |
1113 | cnt += sprintf(&page[cnt], "\n"); | |
c8e5b163 | 1114 | if (cur_ops->stats) |
72e9bb54 | 1115 | cnt += cur_ops->stats(&page[cnt]); |
a241ec65 PM |
1116 | return cnt; |
1117 | } | |
1118 | ||
1119 | /* | |
1120 | * Print torture statistics. Caller must ensure that there is only | |
1121 | * one call to this function at a given time!!! This is normally | |
1122 | * accomplished by relying on the module system to only have one copy | |
1123 | * of the module loaded, and then by giving the rcu_torture_stats | |
1124 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1125 | * thread is not running). | |
1126 | */ | |
1127 | static void | |
1128 | rcu_torture_stats_print(void) | |
1129 | { | |
1130 | int cnt; | |
1131 | ||
1132 | cnt = rcu_torture_printk(printk_buf); | |
1133 | printk(KERN_ALERT "%s", printk_buf); | |
1134 | } | |
1135 | ||
1136 | /* | |
1137 | * Periodically prints torture statistics, if periodic statistics printing | |
1138 | * was specified via the stat_interval module parameter. | |
1139 | * | |
1140 | * No need to worry about fullstop here, since this one doesn't reference | |
1141 | * volatile state or register callbacks. | |
1142 | */ | |
1143 | static int | |
1144 | rcu_torture_stats(void *arg) | |
1145 | { | |
1146 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
1147 | do { | |
1148 | schedule_timeout_interruptible(stat_interval * HZ); | |
1149 | rcu_torture_stats_print(); | |
c9d557c1 PM |
1150 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
1151 | } while (!kthread_should_stop()); | |
a241ec65 PM |
1152 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
1153 | return 0; | |
1154 | } | |
1155 | ||
d84f5203 SV |
1156 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
1157 | ||
1158 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
1159 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
1160 | */ | |
b2896d2e | 1161 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 1162 | { |
d84f5203 SV |
1163 | int i; |
1164 | ||
73d0a4b1 | 1165 | cpumask_setall(shuffle_tmp_mask); |
86ef5c9a | 1166 | get_online_cpus(); |
d84f5203 SV |
1167 | |
1168 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
1169 | if (num_online_cpus() == 1) { |
1170 | put_online_cpus(); | |
1171 | return; | |
1172 | } | |
d84f5203 SV |
1173 | |
1174 | if (rcu_idle_cpu != -1) | |
73d0a4b1 | 1175 | cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); |
d84f5203 | 1176 | |
73d0a4b1 | 1177 | set_cpus_allowed_ptr(current, shuffle_tmp_mask); |
d84f5203 | 1178 | |
c8e5b163 | 1179 | if (reader_tasks) { |
d84f5203 SV |
1180 | for (i = 0; i < nrealreaders; i++) |
1181 | if (reader_tasks[i]) | |
f70316da | 1182 | set_cpus_allowed_ptr(reader_tasks[i], |
73d0a4b1 | 1183 | shuffle_tmp_mask); |
d84f5203 SV |
1184 | } |
1185 | ||
c8e5b163 | 1186 | if (fakewriter_tasks) { |
b772e1dd JT |
1187 | for (i = 0; i < nfakewriters; i++) |
1188 | if (fakewriter_tasks[i]) | |
f70316da | 1189 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
73d0a4b1 | 1190 | shuffle_tmp_mask); |
b772e1dd JT |
1191 | } |
1192 | ||
d84f5203 | 1193 | if (writer_task) |
73d0a4b1 | 1194 | set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); |
d84f5203 SV |
1195 | |
1196 | if (stats_task) | |
73d0a4b1 | 1197 | set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); |
d84f5203 SV |
1198 | |
1199 | if (rcu_idle_cpu == -1) | |
1200 | rcu_idle_cpu = num_online_cpus() - 1; | |
1201 | else | |
1202 | rcu_idle_cpu--; | |
1203 | ||
86ef5c9a | 1204 | put_online_cpus(); |
d84f5203 SV |
1205 | } |
1206 | ||
1207 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
1208 | * system to become idle at a time and cut off its timer ticks. This is meant | |
1209 | * to test the support for such tickless idle CPU in RCU. | |
1210 | */ | |
1211 | static int | |
1212 | rcu_torture_shuffle(void *arg) | |
1213 | { | |
1214 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
1215 | do { | |
1216 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
1217 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
1218 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
1219 | } while (!kthread_should_stop()); | |
d84f5203 SV |
1220 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
1221 | return 0; | |
1222 | } | |
1223 | ||
d120f65f PM |
1224 | /* Cause the rcutorture test to "stutter", starting and stopping all |
1225 | * threads periodically. | |
1226 | */ | |
1227 | static int | |
1228 | rcu_torture_stutter(void *arg) | |
1229 | { | |
1230 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
1231 | do { | |
1232 | schedule_timeout_interruptible(stutter * HZ); | |
1233 | stutter_pause_test = 1; | |
c9d557c1 | 1234 | if (!kthread_should_stop()) |
d120f65f PM |
1235 | schedule_timeout_interruptible(stutter * HZ); |
1236 | stutter_pause_test = 0; | |
c9d557c1 PM |
1237 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
1238 | } while (!kthread_should_stop()); | |
d120f65f PM |
1239 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
1240 | return 0; | |
1241 | } | |
1242 | ||
95c38322 | 1243 | static inline void |
8e8be45e | 1244 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag) |
95c38322 | 1245 | { |
b772e1dd JT |
1246 | printk(KERN_ALERT "%s" TORTURE_FLAG |
1247 | "--- %s: nreaders=%d nfakewriters=%d " | |
95c38322 | 1248 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
bf66f18e | 1249 | "shuffle_interval=%d stutter=%d irqreader=%d " |
8e8be45e PM |
1250 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " |
1251 | "test_boost=%d/%d test_boost_interval=%d " | |
1252 | "test_boost_duration=%d\n", | |
b772e1dd | 1253 | torture_type, tag, nrealreaders, nfakewriters, |
d120f65f | 1254 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, |
8e8be45e PM |
1255 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, |
1256 | test_boost, cur_ops->can_boost, | |
1257 | test_boost_interval, test_boost_duration); | |
95c38322 PM |
1258 | } |
1259 | ||
8e8be45e | 1260 | static struct notifier_block rcutorture_shutdown_nb = { |
343e9099 PM |
1261 | .notifier_call = rcutorture_shutdown_notify, |
1262 | }; | |
1263 | ||
8e8be45e PM |
1264 | static void rcutorture_booster_cleanup(int cpu) |
1265 | { | |
1266 | struct task_struct *t; | |
1267 | ||
1268 | if (boost_tasks[cpu] == NULL) | |
1269 | return; | |
1270 | mutex_lock(&boost_mutex); | |
1271 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task"); | |
1272 | t = boost_tasks[cpu]; | |
1273 | boost_tasks[cpu] = NULL; | |
1274 | mutex_unlock(&boost_mutex); | |
1275 | ||
1276 | /* This must be outside of the mutex, otherwise deadlock! */ | |
1277 | kthread_stop(t); | |
1278 | } | |
1279 | ||
1280 | static int rcutorture_booster_init(int cpu) | |
1281 | { | |
1282 | int retval; | |
1283 | ||
1284 | if (boost_tasks[cpu] != NULL) | |
1285 | return 0; /* Already created, nothing more to do. */ | |
1286 | ||
1287 | /* Don't allow time recalculation while creating a new task. */ | |
1288 | mutex_lock(&boost_mutex); | |
1289 | VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task"); | |
1290 | boost_tasks[cpu] = kthread_create(rcu_torture_boost, NULL, | |
1291 | "rcu_torture_boost"); | |
1292 | if (IS_ERR(boost_tasks[cpu])) { | |
1293 | retval = PTR_ERR(boost_tasks[cpu]); | |
1294 | VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed"); | |
1295 | n_rcu_torture_boost_ktrerror++; | |
1296 | boost_tasks[cpu] = NULL; | |
1297 | mutex_unlock(&boost_mutex); | |
1298 | return retval; | |
1299 | } | |
1300 | kthread_bind(boost_tasks[cpu], cpu); | |
1301 | wake_up_process(boost_tasks[cpu]); | |
1302 | mutex_unlock(&boost_mutex); | |
1303 | return 0; | |
1304 | } | |
1305 | ||
1306 | static int rcutorture_cpu_notify(struct notifier_block *self, | |
1307 | unsigned long action, void *hcpu) | |
1308 | { | |
1309 | long cpu = (long)hcpu; | |
1310 | ||
1311 | switch (action) { | |
1312 | case CPU_ONLINE: | |
1313 | case CPU_DOWN_FAILED: | |
1314 | (void)rcutorture_booster_init(cpu); | |
1315 | break; | |
1316 | case CPU_DOWN_PREPARE: | |
1317 | rcutorture_booster_cleanup(cpu); | |
1318 | break; | |
1319 | default: | |
1320 | break; | |
1321 | } | |
1322 | return NOTIFY_OK; | |
1323 | } | |
1324 | ||
1325 | static struct notifier_block rcutorture_cpu_nb = { | |
1326 | .notifier_call = rcutorture_cpu_notify, | |
1327 | }; | |
1328 | ||
a241ec65 PM |
1329 | static void |
1330 | rcu_torture_cleanup(void) | |
1331 | { | |
1332 | int i; | |
1333 | ||
343e9099 | 1334 | mutex_lock(&fullstop_mutex); |
c9d557c1 PM |
1335 | if (fullstop == FULLSTOP_SHUTDOWN) { |
1336 | printk(KERN_WARNING /* but going down anyway, so... */ | |
1337 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
343e9099 | 1338 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 1339 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1340 | if (cur_ops->cb_barrier != NULL) |
1341 | cur_ops->cb_barrier(); | |
1342 | return; | |
1343 | } | |
c9d557c1 | 1344 | fullstop = FULLSTOP_RMMOD; |
343e9099 | 1345 | mutex_unlock(&fullstop_mutex); |
8e8be45e | 1346 | unregister_reboot_notifier(&rcutorture_shutdown_nb); |
d120f65f PM |
1347 | if (stutter_task) { |
1348 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1349 | kthread_stop(stutter_task); | |
1350 | } | |
1351 | stutter_task = NULL; | |
c8e5b163 | 1352 | if (shuffler_task) { |
d84f5203 SV |
1353 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1354 | kthread_stop(shuffler_task); | |
73d0a4b1 | 1355 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1356 | } |
1357 | shuffler_task = NULL; | |
1358 | ||
c8e5b163 | 1359 | if (writer_task) { |
a241ec65 PM |
1360 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1361 | kthread_stop(writer_task); | |
1362 | } | |
1363 | writer_task = NULL; | |
1364 | ||
c8e5b163 | 1365 | if (reader_tasks) { |
a241ec65 | 1366 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1367 | if (reader_tasks[i]) { |
a241ec65 PM |
1368 | VERBOSE_PRINTK_STRING( |
1369 | "Stopping rcu_torture_reader task"); | |
1370 | kthread_stop(reader_tasks[i]); | |
1371 | } | |
1372 | reader_tasks[i] = NULL; | |
1373 | } | |
1374 | kfree(reader_tasks); | |
1375 | reader_tasks = NULL; | |
1376 | } | |
1377 | rcu_torture_current = NULL; | |
1378 | ||
c8e5b163 | 1379 | if (fakewriter_tasks) { |
b772e1dd | 1380 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1381 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1382 | VERBOSE_PRINTK_STRING( |
1383 | "Stopping rcu_torture_fakewriter task"); | |
1384 | kthread_stop(fakewriter_tasks[i]); | |
1385 | } | |
1386 | fakewriter_tasks[i] = NULL; | |
1387 | } | |
1388 | kfree(fakewriter_tasks); | |
1389 | fakewriter_tasks = NULL; | |
1390 | } | |
1391 | ||
c8e5b163 | 1392 | if (stats_task) { |
a241ec65 PM |
1393 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1394 | kthread_stop(stats_task); | |
1395 | } | |
1396 | stats_task = NULL; | |
1397 | ||
bf66f18e PM |
1398 | if (fqs_task) { |
1399 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task"); | |
1400 | kthread_stop(fqs_task); | |
1401 | } | |
1402 | fqs_task = NULL; | |
8e8be45e PM |
1403 | if ((test_boost == 1 && cur_ops->can_boost) || |
1404 | test_boost == 2) { | |
1405 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1406 | for_each_possible_cpu(i) | |
1407 | rcutorture_booster_cleanup(i); | |
1408 | } | |
bf66f18e | 1409 | |
a241ec65 | 1410 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1411 | |
1412 | if (cur_ops->cb_barrier != NULL) | |
1413 | cur_ops->cb_barrier(); | |
a241ec65 | 1414 | |
a241ec65 | 1415 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1416 | |
c8e5b163 | 1417 | if (cur_ops->cleanup) |
72e9bb54 | 1418 | cur_ops->cleanup(); |
95c38322 | 1419 | if (atomic_read(&n_rcu_torture_error)) |
8e8be45e | 1420 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
95c38322 | 1421 | else |
8e8be45e | 1422 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1423 | } |
1424 | ||
6f8bc500 | 1425 | static int __init |
a241ec65 PM |
1426 | rcu_torture_init(void) |
1427 | { | |
1428 | int i; | |
1429 | int cpu; | |
1430 | int firsterr = 0; | |
ade5fb81 | 1431 | static struct rcu_torture_ops *torture_ops[] = |
d9a3da06 PM |
1432 | { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, |
1433 | &rcu_bh_ops, &rcu_bh_sync_ops, | |
804bb837 PM |
1434 | &srcu_ops, &srcu_expedited_ops, |
1435 | &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; | |
a241ec65 | 1436 | |
343e9099 PM |
1437 | mutex_lock(&fullstop_mutex); |
1438 | ||
a241ec65 | 1439 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1440 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1441 | cur_ops = torture_ops[i]; |
ade5fb81 | 1442 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1443 | break; |
72e9bb54 | 1444 | } |
ade5fb81 | 1445 | if (i == ARRAY_SIZE(torture_ops)) { |
cf886c44 | 1446 | printk(KERN_ALERT "rcu-torture: invalid torture type: \"%s\"\n", |
72e9bb54 | 1447 | torture_type); |
cf886c44 PM |
1448 | printk(KERN_ALERT "rcu-torture types:"); |
1449 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
1450 | printk(KERN_ALERT " %s", torture_ops[i]->name); | |
1451 | printk(KERN_ALERT "\n"); | |
343e9099 | 1452 | mutex_unlock(&fullstop_mutex); |
a71fca58 | 1453 | return -EINVAL; |
72e9bb54 | 1454 | } |
bf66f18e PM |
1455 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
1456 | printk(KERN_ALERT "rcu-torture: ->fqs NULL and non-zero " | |
1457 | "fqs_duration, fqs disabled.\n"); | |
1458 | fqs_duration = 0; | |
1459 | } | |
c8e5b163 | 1460 | if (cur_ops->init) |
72e9bb54 PM |
1461 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1462 | ||
a241ec65 PM |
1463 | if (nreaders >= 0) |
1464 | nrealreaders = nreaders; | |
1465 | else | |
1466 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1467 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
c9d557c1 | 1468 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1469 | |
1470 | /* Set up the freelist. */ | |
1471 | ||
1472 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1473 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1474 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1475 | list_add_tail(&rcu_tortures[i].rtort_free, |
1476 | &rcu_torture_freelist); | |
1477 | } | |
1478 | ||
1479 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1480 | ||
1481 | rcu_torture_current = NULL; | |
1482 | rcu_torture_current_version = 0; | |
1483 | atomic_set(&n_rcu_torture_alloc, 0); | |
1484 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1485 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1486 | atomic_set(&n_rcu_torture_mberror, 0); |
1487 | atomic_set(&n_rcu_torture_error, 0); | |
8e8be45e PM |
1488 | n_rcu_torture_boost_ktrerror = 0; |
1489 | n_rcu_torture_boost_rterror = 0; | |
1490 | n_rcu_torture_boost_allocerror = 0; | |
1491 | n_rcu_torture_boost_afferror = 0; | |
1492 | n_rcu_torture_boost_failure = 0; | |
1493 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1494 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1495 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1496 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1497 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1498 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1499 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1500 | } | |
1501 | } | |
1502 | ||
1503 | /* Start up the kthreads. */ | |
1504 | ||
1505 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
1506 | writer_task = kthread_run(rcu_torture_writer, NULL, | |
1507 | "rcu_torture_writer"); | |
1508 | if (IS_ERR(writer_task)) { | |
1509 | firsterr = PTR_ERR(writer_task); | |
1510 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
1511 | writer_task = NULL; | |
1512 | goto unwind; | |
1513 | } | |
b772e1dd | 1514 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1515 | GFP_KERNEL); |
b772e1dd JT |
1516 | if (fakewriter_tasks == NULL) { |
1517 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1518 | firsterr = -ENOMEM; | |
1519 | goto unwind; | |
1520 | } | |
1521 | for (i = 0; i < nfakewriters; i++) { | |
1522 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
1523 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
a71fca58 | 1524 | "rcu_torture_fakewriter"); |
b772e1dd JT |
1525 | if (IS_ERR(fakewriter_tasks[i])) { |
1526 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
1527 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
1528 | fakewriter_tasks[i] = NULL; | |
1529 | goto unwind; | |
1530 | } | |
1531 | } | |
2860aaba | 1532 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1533 | GFP_KERNEL); |
1534 | if (reader_tasks == NULL) { | |
1535 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1536 | firsterr = -ENOMEM; | |
1537 | goto unwind; | |
1538 | } | |
1539 | for (i = 0; i < nrealreaders; i++) { | |
1540 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
1541 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
1542 | "rcu_torture_reader"); | |
1543 | if (IS_ERR(reader_tasks[i])) { | |
1544 | firsterr = PTR_ERR(reader_tasks[i]); | |
1545 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
1546 | reader_tasks[i] = NULL; | |
1547 | goto unwind; | |
1548 | } | |
1549 | } | |
1550 | if (stat_interval > 0) { | |
1551 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
1552 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
1553 | "rcu_torture_stats"); | |
1554 | if (IS_ERR(stats_task)) { | |
1555 | firsterr = PTR_ERR(stats_task); | |
1556 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
1557 | stats_task = NULL; | |
1558 | goto unwind; | |
1559 | } | |
1560 | } | |
d84f5203 SV |
1561 | if (test_no_idle_hz) { |
1562 | rcu_idle_cpu = num_online_cpus() - 1; | |
73d0a4b1 RR |
1563 | |
1564 | if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { | |
1565 | firsterr = -ENOMEM; | |
1566 | VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); | |
1567 | goto unwind; | |
1568 | } | |
1569 | ||
d84f5203 SV |
1570 | /* Create the shuffler thread */ |
1571 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
1572 | "rcu_torture_shuffle"); | |
1573 | if (IS_ERR(shuffler_task)) { | |
73d0a4b1 | 1574 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1575 | firsterr = PTR_ERR(shuffler_task); |
1576 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
1577 | shuffler_task = NULL; | |
1578 | goto unwind; | |
1579 | } | |
1580 | } | |
d120f65f PM |
1581 | if (stutter < 0) |
1582 | stutter = 0; | |
1583 | if (stutter) { | |
1584 | /* Create the stutter thread */ | |
1585 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
1586 | "rcu_torture_stutter"); | |
1587 | if (IS_ERR(stutter_task)) { | |
1588 | firsterr = PTR_ERR(stutter_task); | |
1589 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
1590 | stutter_task = NULL; | |
1591 | goto unwind; | |
1592 | } | |
1593 | } | |
bf66f18e PM |
1594 | if (fqs_duration < 0) |
1595 | fqs_duration = 0; | |
1596 | if (fqs_duration) { | |
1597 | /* Create the stutter thread */ | |
1598 | fqs_task = kthread_run(rcu_torture_fqs, NULL, | |
1599 | "rcu_torture_fqs"); | |
1600 | if (IS_ERR(fqs_task)) { | |
1601 | firsterr = PTR_ERR(fqs_task); | |
1602 | VERBOSE_PRINTK_ERRSTRING("Failed to create fqs"); | |
1603 | fqs_task = NULL; | |
1604 | goto unwind; | |
1605 | } | |
1606 | } | |
8e8be45e PM |
1607 | if (test_boost_interval < 1) |
1608 | test_boost_interval = 1; | |
1609 | if (test_boost_duration < 2) | |
1610 | test_boost_duration = 2; | |
1611 | if ((test_boost == 1 && cur_ops->can_boost) || | |
1612 | test_boost == 2) { | |
1613 | int retval; | |
1614 | ||
1615 | boost_starttime = jiffies + test_boost_interval * HZ; | |
1616 | register_cpu_notifier(&rcutorture_cpu_nb); | |
1617 | for_each_possible_cpu(i) { | |
1618 | if (cpu_is_offline(i)) | |
1619 | continue; /* Heuristic: CPU can go offline. */ | |
1620 | retval = rcutorture_booster_init(i); | |
1621 | if (retval < 0) { | |
1622 | firsterr = retval; | |
1623 | goto unwind; | |
1624 | } | |
1625 | } | |
1626 | } | |
1627 | register_reboot_notifier(&rcutorture_shutdown_nb); | |
343e9099 | 1628 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1629 | return 0; |
1630 | ||
1631 | unwind: | |
343e9099 | 1632 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1633 | rcu_torture_cleanup(); |
1634 | return firsterr; | |
1635 | } | |
1636 | ||
1637 | module_init(rcu_torture_init); | |
1638 | module_exit(rcu_torture_cleanup); |