Commit | Line | Data |
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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> |
f07767fd | 49 | #include <asm/byteorder.h> |
a241ec65 PM |
50 | |
51 | MODULE_LICENSE("GPL"); | |
b772e1dd | 52 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and " |
a71fca58 | 53 | "Josh Triplett <josh@freedesktop.org>"); |
a241ec65 | 54 | |
4802211c | 55 | static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ |
b772e1dd | 56 | static int nfakewriters = 4; /* # fake writer threads */ |
d84f5203 | 57 | static int stat_interval; /* Interval between stats, in seconds. */ |
a241ec65 | 58 | /* Defaults to "only at end of test". */ |
d84f5203 SV |
59 | static int verbose; /* Print more debug info. */ |
60 | static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ | |
d120f65f PM |
61 | static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ |
62 | static int stutter = 5; /* Start/stop testing interval (in sec) */ | |
0729fbf3 | 63 | static int irqreader = 1; /* RCU readers from irq (timers). */ |
d5f546d8 PM |
64 | static int fqs_duration; /* Duration of bursts (us), 0 to disable. */ |
65 | static int fqs_holdoff; /* Hold time within burst (us). */ | |
bf66f18e | 66 | static int fqs_stutter = 3; /* Wait time between bursts (s). */ |
d5f546d8 | 67 | static int shutdown_secs; /* Shutdown time (s). <=0 for no shutdown. */ |
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"); |
3721bc1d | 77 | module_param(stat_interval, int, 0644); |
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)"); | |
d5f546d8 PM |
95 | module_param(shutdown_secs, int, 0444); |
96 | MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), zero to disable."); | |
8e8be45e PM |
97 | module_param(test_boost, int, 0444); |
98 | MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); | |
99 | module_param(test_boost_interval, int, 0444); | |
100 | MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds."); | |
101 | module_param(test_boost_duration, int, 0444); | |
102 | MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds."); | |
d6ad6711 | 103 | module_param(torture_type, charp, 0444); |
b2896d2e | 104 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); |
72e9bb54 PM |
105 | |
106 | #define TORTURE_FLAG "-torture:" | |
a241ec65 | 107 | #define PRINTK_STRING(s) \ |
72e9bb54 | 108 | do { printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 109 | #define VERBOSE_PRINTK_STRING(s) \ |
72e9bb54 | 110 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 111 | #define VERBOSE_PRINTK_ERRSTRING(s) \ |
72e9bb54 | 112 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) |
a241ec65 PM |
113 | |
114 | static char printk_buf[4096]; | |
115 | ||
116 | static int nrealreaders; | |
117 | static struct task_struct *writer_task; | |
b772e1dd | 118 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
119 | static struct task_struct **reader_tasks; |
120 | static struct task_struct *stats_task; | |
d84f5203 | 121 | static struct task_struct *shuffler_task; |
d120f65f | 122 | static struct task_struct *stutter_task; |
bf66f18e | 123 | static struct task_struct *fqs_task; |
8e8be45e | 124 | static struct task_struct *boost_tasks[NR_CPUS]; |
d5f546d8 | 125 | static struct task_struct *shutdown_task; |
a241ec65 PM |
126 | |
127 | #define RCU_TORTURE_PIPE_LEN 10 | |
128 | ||
129 | struct rcu_torture { | |
130 | struct rcu_head rtort_rcu; | |
131 | int rtort_pipe_count; | |
132 | struct list_head rtort_free; | |
996417d2 | 133 | int rtort_mbtest; |
a241ec65 PM |
134 | }; |
135 | ||
a241ec65 | 136 | static LIST_HEAD(rcu_torture_freelist); |
0ddea0ea | 137 | static struct rcu_torture __rcu *rcu_torture_current; |
4a298656 | 138 | static unsigned long rcu_torture_current_version; |
a241ec65 PM |
139 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
140 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
141 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = | |
142 | { 0 }; | |
143 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = | |
144 | { 0 }; | |
145 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; | |
b2896d2e PM |
146 | static atomic_t n_rcu_torture_alloc; |
147 | static atomic_t n_rcu_torture_alloc_fail; | |
148 | static atomic_t n_rcu_torture_free; | |
149 | static atomic_t n_rcu_torture_mberror; | |
150 | static atomic_t n_rcu_torture_error; | |
8e8be45e PM |
151 | static long n_rcu_torture_boost_ktrerror; |
152 | static long n_rcu_torture_boost_rterror; | |
8e8be45e PM |
153 | static long n_rcu_torture_boost_failure; |
154 | static long n_rcu_torture_boosts; | |
a71fca58 | 155 | static long n_rcu_torture_timers; |
e3033736 | 156 | static struct list_head rcu_torture_removed; |
73d0a4b1 | 157 | static cpumask_var_t shuffle_tmp_mask; |
a241ec65 | 158 | |
a71fca58 | 159 | static int stutter_pause_test; |
d120f65f | 160 | |
31a72bce PM |
161 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
162 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
163 | #else | |
164 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
165 | #endif | |
166 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
167 | ||
3acf4a9a | 168 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 169 | #define rcu_can_boost() 1 |
3acf4a9a | 170 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 171 | #define rcu_can_boost() 0 |
3acf4a9a | 172 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 173 | |
d5f546d8 | 174 | static unsigned long shutdown_time; /* jiffies to system shutdown. */ |
8e8be45e PM |
175 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
176 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
177 | /* and boost task create/destroy. */ | |
178 | ||
c9d557c1 PM |
179 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
180 | ||
181 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
182 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
183 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
184 | static int fullstop = FULLSTOP_RMMOD; | |
0ddea0ea PM |
185 | /* |
186 | * Protect fullstop transitions and spawning of kthreads. | |
187 | */ | |
188 | static DEFINE_MUTEX(fullstop_mutex); | |
343e9099 | 189 | |
d5f546d8 PM |
190 | /* Forward reference. */ |
191 | static void rcu_torture_cleanup(void); | |
192 | ||
343e9099 | 193 | /* |
c9d557c1 | 194 | * Detect and respond to a system shutdown. |
343e9099 PM |
195 | */ |
196 | static int | |
197 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
198 | unsigned long unused2, void *unused3) | |
199 | { | |
c59ab97e | 200 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 201 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 202 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 PM |
203 | else |
204 | printk(KERN_WARNING /* but going down anyway, so... */ | |
205 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
c59ab97e | 206 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
207 | return NOTIFY_DONE; |
208 | } | |
209 | ||
c9d557c1 PM |
210 | /* |
211 | * Absorb kthreads into a kernel function that won't return, so that | |
212 | * they won't ever access module text or data again. | |
213 | */ | |
214 | static void rcutorture_shutdown_absorb(char *title) | |
215 | { | |
216 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
217 | printk(KERN_NOTICE | |
218 | "rcutorture thread %s parking due to system shutdown\n", | |
219 | title); | |
220 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
221 | } | |
222 | } | |
223 | ||
a241ec65 PM |
224 | /* |
225 | * Allocate an element from the rcu_tortures pool. | |
226 | */ | |
97a41e26 | 227 | static struct rcu_torture * |
a241ec65 PM |
228 | rcu_torture_alloc(void) |
229 | { | |
230 | struct list_head *p; | |
231 | ||
adac1665 | 232 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
233 | if (list_empty(&rcu_torture_freelist)) { |
234 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 235 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
236 | return NULL; |
237 | } | |
238 | atomic_inc(&n_rcu_torture_alloc); | |
239 | p = rcu_torture_freelist.next; | |
240 | list_del_init(p); | |
adac1665 | 241 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
242 | return container_of(p, struct rcu_torture, rtort_free); |
243 | } | |
244 | ||
245 | /* | |
246 | * Free an element to the rcu_tortures pool. | |
247 | */ | |
248 | static void | |
249 | rcu_torture_free(struct rcu_torture *p) | |
250 | { | |
251 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 252 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 253 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 254 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
255 | } |
256 | ||
a241ec65 PM |
257 | struct rcu_random_state { |
258 | unsigned long rrs_state; | |
75cfef32 | 259 | long rrs_count; |
a241ec65 PM |
260 | }; |
261 | ||
262 | #define RCU_RANDOM_MULT 39916801 /* prime */ | |
263 | #define RCU_RANDOM_ADD 479001701 /* prime */ | |
264 | #define RCU_RANDOM_REFRESH 10000 | |
265 | ||
266 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } | |
267 | ||
268 | /* | |
269 | * Crude but fast random-number generator. Uses a linear congruential | |
c17ac855 | 270 | * generator, with occasional help from cpu_clock(). |
a241ec65 | 271 | */ |
75cfef32 | 272 | static unsigned long |
a241ec65 PM |
273 | rcu_random(struct rcu_random_state *rrsp) |
274 | { | |
a241ec65 | 275 | if (--rrsp->rrs_count < 0) { |
c676329a | 276 | rrsp->rrs_state += (unsigned long)local_clock(); |
a241ec65 PM |
277 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
278 | } | |
279 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; | |
280 | return swahw32(rrsp->rrs_state); | |
281 | } | |
282 | ||
d120f65f | 283 | static void |
c9d557c1 | 284 | rcu_stutter_wait(char *title) |
d120f65f | 285 | { |
c9d557c1 | 286 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
287 | if (rcutorture_runnable) |
288 | schedule_timeout_interruptible(1); | |
289 | else | |
3ccf79f4 | 290 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 291 | rcutorture_shutdown_absorb(title); |
343e9099 | 292 | } |
d120f65f PM |
293 | } |
294 | ||
72e9bb54 PM |
295 | /* |
296 | * Operations vector for selecting different types of tests. | |
297 | */ | |
298 | ||
299 | struct rcu_torture_ops { | |
300 | void (*init)(void); | |
301 | void (*cleanup)(void); | |
302 | int (*readlock)(void); | |
0acc512c | 303 | void (*read_delay)(struct rcu_random_state *rrsp); |
72e9bb54 PM |
304 | void (*readunlock)(int idx); |
305 | int (*completed)(void); | |
0acc512c | 306 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 307 | void (*sync)(void); |
2326974d | 308 | void (*cb_barrier)(void); |
bf66f18e | 309 | void (*fqs)(void); |
72e9bb54 | 310 | int (*stats)(char *page); |
0acc512c | 311 | int irq_capable; |
8e8be45e | 312 | int can_boost; |
72e9bb54 PM |
313 | char *name; |
314 | }; | |
a71fca58 PM |
315 | |
316 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
317 | |
318 | /* | |
319 | * Definitions for rcu torture testing. | |
320 | */ | |
321 | ||
a49a4af7 | 322 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
323 | { |
324 | rcu_read_lock(); | |
325 | return 0; | |
326 | } | |
327 | ||
b2896d2e PM |
328 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
329 | { | |
b8d57a76 JT |
330 | const unsigned long shortdelay_us = 200; |
331 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 332 | |
b8d57a76 JT |
333 | /* We want a short delay sometimes to make a reader delay the grace |
334 | * period, and we want a long delay occasionally to trigger | |
335 | * force_quiescent_state. */ | |
b2896d2e | 336 | |
b8d57a76 JT |
337 | if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
338 | mdelay(longdelay_ms); | |
339 | if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) | |
340 | udelay(shortdelay_us); | |
e546f485 LJ |
341 | #ifdef CONFIG_PREEMPT |
342 | if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000))) | |
343 | preempt_schedule(); /* No QS if preempt_disable() in effect */ | |
344 | #endif | |
b2896d2e PM |
345 | } |
346 | ||
a49a4af7 | 347 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
348 | { |
349 | rcu_read_unlock(); | |
350 | } | |
351 | ||
352 | static int rcu_torture_completed(void) | |
353 | { | |
354 | return rcu_batches_completed(); | |
355 | } | |
356 | ||
357 | static void | |
358 | rcu_torture_cb(struct rcu_head *p) | |
359 | { | |
360 | int i; | |
361 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
362 | ||
c9d557c1 | 363 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
364 | /* Test is ending, just drop callbacks on the floor. */ |
365 | /* The next initialization will pick up the pieces. */ | |
366 | return; | |
367 | } | |
368 | i = rp->rtort_pipe_count; | |
369 | if (i > RCU_TORTURE_PIPE_LEN) | |
370 | i = RCU_TORTURE_PIPE_LEN; | |
371 | atomic_inc(&rcu_torture_wcount[i]); | |
372 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
373 | rp->rtort_mbtest = 0; | |
374 | rcu_torture_free(rp); | |
375 | } else | |
0acc512c | 376 | cur_ops->deferred_free(rp); |
72e9bb54 PM |
377 | } |
378 | ||
d9a3da06 PM |
379 | static int rcu_no_completed(void) |
380 | { | |
381 | return 0; | |
382 | } | |
383 | ||
72e9bb54 PM |
384 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
385 | { | |
386 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
387 | } | |
388 | ||
389 | static struct rcu_torture_ops rcu_ops = { | |
0acc512c PM |
390 | .init = NULL, |
391 | .cleanup = NULL, | |
392 | .readlock = rcu_torture_read_lock, | |
393 | .read_delay = rcu_read_delay, | |
394 | .readunlock = rcu_torture_read_unlock, | |
395 | .completed = rcu_torture_completed, | |
396 | .deferred_free = rcu_torture_deferred_free, | |
397 | .sync = synchronize_rcu, | |
398 | .cb_barrier = rcu_barrier, | |
bf66f18e | 399 | .fqs = rcu_force_quiescent_state, |
0acc512c | 400 | .stats = NULL, |
a71fca58 | 401 | .irq_capable = 1, |
8e8be45e | 402 | .can_boost = rcu_can_boost(), |
a71fca58 | 403 | .name = "rcu" |
72e9bb54 PM |
404 | }; |
405 | ||
e3033736 JT |
406 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
407 | { | |
408 | int i; | |
409 | struct rcu_torture *rp; | |
410 | struct rcu_torture *rp1; | |
411 | ||
412 | cur_ops->sync(); | |
413 | list_add(&p->rtort_free, &rcu_torture_removed); | |
414 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
415 | i = rp->rtort_pipe_count; | |
416 | if (i > RCU_TORTURE_PIPE_LEN) | |
417 | i = RCU_TORTURE_PIPE_LEN; | |
418 | atomic_inc(&rcu_torture_wcount[i]); | |
419 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
420 | rp->rtort_mbtest = 0; | |
421 | list_del(&rp->rtort_free); | |
422 | rcu_torture_free(rp); | |
423 | } | |
424 | } | |
425 | } | |
426 | ||
427 | static void rcu_sync_torture_init(void) | |
428 | { | |
429 | INIT_LIST_HEAD(&rcu_torture_removed); | |
430 | } | |
431 | ||
20d2e428 | 432 | static struct rcu_torture_ops rcu_sync_ops = { |
0acc512c PM |
433 | .init = rcu_sync_torture_init, |
434 | .cleanup = NULL, | |
435 | .readlock = rcu_torture_read_lock, | |
436 | .read_delay = rcu_read_delay, | |
437 | .readunlock = rcu_torture_read_unlock, | |
438 | .completed = rcu_torture_completed, | |
439 | .deferred_free = rcu_sync_torture_deferred_free, | |
440 | .sync = synchronize_rcu, | |
441 | .cb_barrier = NULL, | |
bf66f18e | 442 | .fqs = rcu_force_quiescent_state, |
0acc512c PM |
443 | .stats = NULL, |
444 | .irq_capable = 1, | |
8e8be45e | 445 | .can_boost = rcu_can_boost(), |
0acc512c | 446 | .name = "rcu_sync" |
20d2e428 JT |
447 | }; |
448 | ||
d9a3da06 PM |
449 | static struct rcu_torture_ops rcu_expedited_ops = { |
450 | .init = rcu_sync_torture_init, | |
451 | .cleanup = NULL, | |
452 | .readlock = rcu_torture_read_lock, | |
453 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
454 | .readunlock = rcu_torture_read_unlock, | |
455 | .completed = rcu_no_completed, | |
456 | .deferred_free = rcu_sync_torture_deferred_free, | |
457 | .sync = synchronize_rcu_expedited, | |
458 | .cb_barrier = NULL, | |
bf66f18e | 459 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
460 | .stats = NULL, |
461 | .irq_capable = 1, | |
8e8be45e | 462 | .can_boost = rcu_can_boost(), |
d9a3da06 PM |
463 | .name = "rcu_expedited" |
464 | }; | |
465 | ||
c32e0660 PM |
466 | /* |
467 | * Definitions for rcu_bh torture testing. | |
468 | */ | |
469 | ||
a49a4af7 | 470 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
471 | { |
472 | rcu_read_lock_bh(); | |
473 | return 0; | |
474 | } | |
475 | ||
a49a4af7 | 476 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
477 | { |
478 | rcu_read_unlock_bh(); | |
479 | } | |
480 | ||
481 | static int rcu_bh_torture_completed(void) | |
482 | { | |
483 | return rcu_batches_completed_bh(); | |
484 | } | |
485 | ||
486 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
487 | { | |
488 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
489 | } | |
490 | ||
491 | static struct rcu_torture_ops rcu_bh_ops = { | |
0acc512c PM |
492 | .init = NULL, |
493 | .cleanup = NULL, | |
494 | .readlock = rcu_bh_torture_read_lock, | |
495 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
496 | .readunlock = rcu_bh_torture_read_unlock, | |
497 | .completed = rcu_bh_torture_completed, | |
498 | .deferred_free = rcu_bh_torture_deferred_free, | |
bdf2a436 | 499 | .sync = synchronize_rcu_bh, |
0acc512c | 500 | .cb_barrier = rcu_barrier_bh, |
bf66f18e | 501 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
502 | .stats = NULL, |
503 | .irq_capable = 1, | |
504 | .name = "rcu_bh" | |
c32e0660 PM |
505 | }; |
506 | ||
11a14701 | 507 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
0acc512c PM |
508 | .init = rcu_sync_torture_init, |
509 | .cleanup = NULL, | |
510 | .readlock = rcu_bh_torture_read_lock, | |
511 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
512 | .readunlock = rcu_bh_torture_read_unlock, | |
513 | .completed = rcu_bh_torture_completed, | |
514 | .deferred_free = rcu_sync_torture_deferred_free, | |
bdf2a436 | 515 | .sync = synchronize_rcu_bh, |
0acc512c | 516 | .cb_barrier = NULL, |
bf66f18e | 517 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
518 | .stats = NULL, |
519 | .irq_capable = 1, | |
520 | .name = "rcu_bh_sync" | |
11a14701 JT |
521 | }; |
522 | ||
bdf2a436 PM |
523 | static struct rcu_torture_ops rcu_bh_expedited_ops = { |
524 | .init = rcu_sync_torture_init, | |
525 | .cleanup = NULL, | |
526 | .readlock = rcu_bh_torture_read_lock, | |
527 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
528 | .readunlock = rcu_bh_torture_read_unlock, | |
529 | .completed = rcu_bh_torture_completed, | |
530 | .deferred_free = rcu_sync_torture_deferred_free, | |
531 | .sync = synchronize_rcu_bh_expedited, | |
532 | .cb_barrier = NULL, | |
533 | .fqs = rcu_bh_force_quiescent_state, | |
534 | .stats = NULL, | |
535 | .irq_capable = 1, | |
536 | .name = "rcu_bh_expedited" | |
537 | }; | |
538 | ||
b2896d2e PM |
539 | /* |
540 | * Definitions for srcu torture testing. | |
541 | */ | |
542 | ||
543 | static struct srcu_struct srcu_ctl; | |
b2896d2e PM |
544 | |
545 | static void srcu_torture_init(void) | |
546 | { | |
547 | init_srcu_struct(&srcu_ctl); | |
e3033736 | 548 | rcu_sync_torture_init(); |
b2896d2e PM |
549 | } |
550 | ||
551 | static void srcu_torture_cleanup(void) | |
552 | { | |
553 | synchronize_srcu(&srcu_ctl); | |
554 | cleanup_srcu_struct(&srcu_ctl); | |
555 | } | |
556 | ||
012d3ca8 | 557 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
558 | { |
559 | return srcu_read_lock(&srcu_ctl); | |
560 | } | |
561 | ||
562 | static void srcu_read_delay(struct rcu_random_state *rrsp) | |
563 | { | |
564 | long delay; | |
565 | const long uspertick = 1000000 / HZ; | |
566 | const long longdelay = 10; | |
567 | ||
568 | /* We want there to be long-running readers, but not all the time. */ | |
569 | ||
570 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); | |
571 | if (!delay) | |
572 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
573 | else |
574 | rcu_read_delay(rrsp); | |
b2896d2e PM |
575 | } |
576 | ||
012d3ca8 | 577 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
578 | { |
579 | srcu_read_unlock(&srcu_ctl, idx); | |
580 | } | |
581 | ||
582 | static int srcu_torture_completed(void) | |
583 | { | |
584 | return srcu_batches_completed(&srcu_ctl); | |
585 | } | |
586 | ||
b772e1dd JT |
587 | static void srcu_torture_synchronize(void) |
588 | { | |
589 | synchronize_srcu(&srcu_ctl); | |
590 | } | |
591 | ||
b2896d2e PM |
592 | static int srcu_torture_stats(char *page) |
593 | { | |
594 | int cnt = 0; | |
595 | int cpu; | |
596 | int idx = srcu_ctl.completed & 0x1; | |
597 | ||
598 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", | |
599 | torture_type, TORTURE_FLAG, idx); | |
600 | for_each_possible_cpu(cpu) { | |
601 | cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu, | |
602 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], | |
603 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
604 | } | |
605 | cnt += sprintf(&page[cnt], "\n"); | |
606 | return cnt; | |
607 | } | |
608 | ||
609 | static struct rcu_torture_ops srcu_ops = { | |
0acc512c PM |
610 | .init = srcu_torture_init, |
611 | .cleanup = srcu_torture_cleanup, | |
612 | .readlock = srcu_torture_read_lock, | |
613 | .read_delay = srcu_read_delay, | |
614 | .readunlock = srcu_torture_read_unlock, | |
615 | .completed = srcu_torture_completed, | |
616 | .deferred_free = rcu_sync_torture_deferred_free, | |
617 | .sync = srcu_torture_synchronize, | |
618 | .cb_barrier = NULL, | |
619 | .stats = srcu_torture_stats, | |
620 | .name = "srcu" | |
b2896d2e PM |
621 | }; |
622 | ||
804bb837 PM |
623 | static void srcu_torture_synchronize_expedited(void) |
624 | { | |
625 | synchronize_srcu_expedited(&srcu_ctl); | |
626 | } | |
627 | ||
628 | static struct rcu_torture_ops srcu_expedited_ops = { | |
629 | .init = srcu_torture_init, | |
630 | .cleanup = srcu_torture_cleanup, | |
631 | .readlock = srcu_torture_read_lock, | |
632 | .read_delay = srcu_read_delay, | |
633 | .readunlock = srcu_torture_read_unlock, | |
634 | .completed = srcu_torture_completed, | |
635 | .deferred_free = rcu_sync_torture_deferred_free, | |
636 | .sync = srcu_torture_synchronize_expedited, | |
637 | .cb_barrier = NULL, | |
638 | .stats = srcu_torture_stats, | |
639 | .name = "srcu_expedited" | |
640 | }; | |
641 | ||
4b6c2cca JT |
642 | /* |
643 | * Definitions for sched torture testing. | |
644 | */ | |
645 | ||
646 | static int sched_torture_read_lock(void) | |
647 | { | |
648 | preempt_disable(); | |
649 | return 0; | |
650 | } | |
651 | ||
652 | static void sched_torture_read_unlock(int idx) | |
653 | { | |
654 | preempt_enable(); | |
655 | } | |
656 | ||
2326974d PM |
657 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
658 | { | |
659 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
660 | } | |
661 | ||
4b6c2cca | 662 | static struct rcu_torture_ops sched_ops = { |
0acc512c PM |
663 | .init = rcu_sync_torture_init, |
664 | .cleanup = NULL, | |
665 | .readlock = sched_torture_read_lock, | |
666 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
667 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 668 | .completed = rcu_no_completed, |
0acc512c | 669 | .deferred_free = rcu_sched_torture_deferred_free, |
bdf2a436 | 670 | .sync = synchronize_sched, |
0acc512c | 671 | .cb_barrier = rcu_barrier_sched, |
bf66f18e | 672 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
673 | .stats = NULL, |
674 | .irq_capable = 1, | |
675 | .name = "sched" | |
4b6c2cca JT |
676 | }; |
677 | ||
804bb837 | 678 | static struct rcu_torture_ops sched_sync_ops = { |
0acc512c PM |
679 | .init = rcu_sync_torture_init, |
680 | .cleanup = NULL, | |
681 | .readlock = sched_torture_read_lock, | |
682 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
683 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 684 | .completed = rcu_no_completed, |
0acc512c | 685 | .deferred_free = rcu_sync_torture_deferred_free, |
bdf2a436 | 686 | .sync = synchronize_sched, |
0acc512c | 687 | .cb_barrier = NULL, |
bf66f18e | 688 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
689 | .stats = NULL, |
690 | .name = "sched_sync" | |
691 | }; | |
692 | ||
0acc512c PM |
693 | static struct rcu_torture_ops sched_expedited_ops = { |
694 | .init = rcu_sync_torture_init, | |
695 | .cleanup = NULL, | |
696 | .readlock = sched_torture_read_lock, | |
697 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
698 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 699 | .completed = rcu_no_completed, |
0acc512c PM |
700 | .deferred_free = rcu_sync_torture_deferred_free, |
701 | .sync = synchronize_sched_expedited, | |
702 | .cb_barrier = NULL, | |
bf66f18e | 703 | .fqs = rcu_sched_force_quiescent_state, |
969c7921 | 704 | .stats = NULL, |
0acc512c PM |
705 | .irq_capable = 1, |
706 | .name = "sched_expedited" | |
2326974d PM |
707 | }; |
708 | ||
8e8be45e PM |
709 | /* |
710 | * RCU torture priority-boost testing. Runs one real-time thread per | |
711 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
712 | * spinning waiting for them to be invoked. If a given callback takes | |
713 | * too long to be invoked, we assume that priority inversion has occurred. | |
714 | */ | |
715 | ||
716 | struct rcu_boost_inflight { | |
717 | struct rcu_head rcu; | |
718 | int inflight; | |
719 | }; | |
720 | ||
721 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
722 | { | |
723 | struct rcu_boost_inflight *rbip = | |
724 | container_of(head, struct rcu_boost_inflight, rcu); | |
725 | ||
726 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
727 | rbip->inflight = 0; | |
728 | } | |
729 | ||
730 | static int rcu_torture_boost(void *arg) | |
731 | { | |
732 | unsigned long call_rcu_time; | |
733 | unsigned long endtime; | |
734 | unsigned long oldstarttime; | |
735 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
736 | struct sched_param sp; | |
737 | ||
738 | VERBOSE_PRINTK_STRING("rcu_torture_boost started"); | |
739 | ||
740 | /* Set real-time priority. */ | |
741 | sp.sched_priority = 1; | |
742 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
743 | VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!"); | |
744 | n_rcu_torture_boost_rterror++; | |
745 | } | |
746 | ||
561190e3 | 747 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
748 | /* Each pass through the following loop does one boost-test cycle. */ |
749 | do { | |
750 | /* Wait for the next test interval. */ | |
751 | oldstarttime = boost_starttime; | |
93898fb1 | 752 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
8e8be45e PM |
753 | schedule_timeout_uninterruptible(1); |
754 | rcu_stutter_wait("rcu_torture_boost"); | |
755 | if (kthread_should_stop() || | |
756 | fullstop != FULLSTOP_DONTSTOP) | |
757 | goto checkwait; | |
758 | } | |
759 | ||
760 | /* Do one boost-test interval. */ | |
761 | endtime = oldstarttime + test_boost_duration * HZ; | |
762 | call_rcu_time = jiffies; | |
93898fb1 | 763 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e PM |
764 | /* If we don't have a callback in flight, post one. */ |
765 | if (!rbi.inflight) { | |
766 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
767 | rbi.inflight = 1; | |
768 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
769 | if (jiffies - call_rcu_time > | |
770 | test_boost_duration * HZ - HZ / 2) { | |
771 | VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed"); | |
772 | n_rcu_torture_boost_failure++; | |
773 | } | |
774 | call_rcu_time = jiffies; | |
775 | } | |
776 | cond_resched(); | |
777 | rcu_stutter_wait("rcu_torture_boost"); | |
778 | if (kthread_should_stop() || | |
779 | fullstop != FULLSTOP_DONTSTOP) | |
780 | goto checkwait; | |
781 | } | |
782 | ||
783 | /* | |
784 | * Set the start time of the next test interval. | |
785 | * Yes, this is vulnerable to long delays, but such | |
786 | * delays simply cause a false negative for the next | |
787 | * interval. Besides, we are running at RT priority, | |
788 | * so delays should be relatively rare. | |
789 | */ | |
ab8f11e5 PM |
790 | while (oldstarttime == boost_starttime && |
791 | !kthread_should_stop()) { | |
8e8be45e PM |
792 | if (mutex_trylock(&boost_mutex)) { |
793 | boost_starttime = jiffies + | |
794 | test_boost_interval * HZ; | |
795 | n_rcu_torture_boosts++; | |
796 | mutex_unlock(&boost_mutex); | |
797 | break; | |
798 | } | |
799 | schedule_timeout_uninterruptible(1); | |
800 | } | |
801 | ||
802 | /* Go do the stutter. */ | |
803 | checkwait: rcu_stutter_wait("rcu_torture_boost"); | |
804 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
805 | ||
806 | /* Clean up and exit. */ | |
807 | VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping"); | |
808 | rcutorture_shutdown_absorb("rcu_torture_boost"); | |
809 | while (!kthread_should_stop() || rbi.inflight) | |
810 | schedule_timeout_uninterruptible(1); | |
811 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ | |
9d68197c | 812 | destroy_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
813 | return 0; |
814 | } | |
815 | ||
bf66f18e PM |
816 | /* |
817 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
818 | * bursts of calls to force_quiescent_state(), increasing the probability | |
819 | * of occurrence of some important types of race conditions. | |
820 | */ | |
821 | static int | |
822 | rcu_torture_fqs(void *arg) | |
823 | { | |
824 | unsigned long fqs_resume_time; | |
825 | int fqs_burst_remaining; | |
826 | ||
827 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task started"); | |
828 | do { | |
829 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
830 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
831 | !kthread_should_stop()) { | |
bf66f18e PM |
832 | schedule_timeout_interruptible(1); |
833 | } | |
834 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
835 | while (fqs_burst_remaining > 0 && |
836 | !kthread_should_stop()) { | |
bf66f18e PM |
837 | cur_ops->fqs(); |
838 | udelay(fqs_holdoff); | |
839 | fqs_burst_remaining -= fqs_holdoff; | |
840 | } | |
841 | rcu_stutter_wait("rcu_torture_fqs"); | |
842 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
843 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping"); | |
844 | rcutorture_shutdown_absorb("rcu_torture_fqs"); | |
845 | while (!kthread_should_stop()) | |
846 | schedule_timeout_uninterruptible(1); | |
847 | return 0; | |
848 | } | |
849 | ||
a241ec65 PM |
850 | /* |
851 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
852 | * for that pointed to by rcu_torture_current, freeing the old structure | |
853 | * after a series of grace periods (the "pipeline"). | |
854 | */ | |
855 | static int | |
856 | rcu_torture_writer(void *arg) | |
857 | { | |
858 | int i; | |
859 | long oldbatch = rcu_batches_completed(); | |
860 | struct rcu_torture *rp; | |
861 | struct rcu_torture *old_rp; | |
862 | static DEFINE_RCU_RANDOM(rand); | |
863 | ||
864 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
865 | set_user_nice(current, 19); |
866 | ||
a241ec65 PM |
867 | do { |
868 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
869 | rp = rcu_torture_alloc(); |
870 | if (rp == NULL) | |
a241ec65 PM |
871 | continue; |
872 | rp->rtort_pipe_count = 0; | |
873 | udelay(rcu_random(&rand) & 0x3ff); | |
0ddea0ea PM |
874 | old_rp = rcu_dereference_check(rcu_torture_current, |
875 | current == writer_task); | |
996417d2 | 876 | rp->rtort_mbtest = 1; |
a241ec65 | 877 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 878 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 879 | if (old_rp) { |
a241ec65 PM |
880 | i = old_rp->rtort_pipe_count; |
881 | if (i > RCU_TORTURE_PIPE_LEN) | |
882 | i = RCU_TORTURE_PIPE_LEN; | |
883 | atomic_inc(&rcu_torture_wcount[i]); | |
884 | old_rp->rtort_pipe_count++; | |
0acc512c | 885 | cur_ops->deferred_free(old_rp); |
a241ec65 | 886 | } |
4a298656 | 887 | rcutorture_record_progress(++rcu_torture_current_version); |
72e9bb54 | 888 | oldbatch = cur_ops->completed(); |
c9d557c1 PM |
889 | rcu_stutter_wait("rcu_torture_writer"); |
890 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 891 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
892 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
893 | while (!kthread_should_stop()) | |
a241ec65 PM |
894 | schedule_timeout_uninterruptible(1); |
895 | return 0; | |
896 | } | |
897 | ||
b772e1dd JT |
898 | /* |
899 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
900 | * delay between calls. | |
901 | */ | |
902 | static int | |
903 | rcu_torture_fakewriter(void *arg) | |
904 | { | |
905 | DEFINE_RCU_RANDOM(rand); | |
906 | ||
907 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
908 | set_user_nice(current, 19); | |
909 | ||
910 | do { | |
911 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); | |
912 | udelay(rcu_random(&rand) & 0x3ff); | |
913 | cur_ops->sync(); | |
c9d557c1 PM |
914 | rcu_stutter_wait("rcu_torture_fakewriter"); |
915 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
916 | |
917 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
918 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
919 | while (!kthread_should_stop()) | |
b772e1dd JT |
920 | schedule_timeout_uninterruptible(1); |
921 | return 0; | |
922 | } | |
923 | ||
91afaf30 PM |
924 | void rcutorture_trace_dump(void) |
925 | { | |
926 | static atomic_t beenhere = ATOMIC_INIT(0); | |
927 | ||
928 | if (atomic_read(&beenhere)) | |
929 | return; | |
930 | if (atomic_xchg(&beenhere, 1) != 0) | |
931 | return; | |
932 | do_trace_rcu_torture_read(cur_ops->name, (struct rcu_head *)~0UL); | |
933 | ftrace_dump(DUMP_ALL); | |
934 | } | |
935 | ||
0729fbf3 PM |
936 | /* |
937 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
938 | * incrementing the corresponding element of the pipeline array. The | |
939 | * counter in the element should never be greater than 1, otherwise, the | |
940 | * RCU implementation is broken. | |
941 | */ | |
942 | static void rcu_torture_timer(unsigned long unused) | |
943 | { | |
944 | int idx; | |
945 | int completed; | |
946 | static DEFINE_RCU_RANDOM(rand); | |
947 | static DEFINE_SPINLOCK(rand_lock); | |
948 | struct rcu_torture *p; | |
949 | int pipe_count; | |
950 | ||
951 | idx = cur_ops->readlock(); | |
952 | completed = cur_ops->completed(); | |
632ee200 | 953 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
954 | rcu_read_lock_bh_held() || |
955 | rcu_read_lock_sched_held() || | |
956 | srcu_read_lock_held(&srcu_ctl)); | |
91afaf30 | 957 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); |
0729fbf3 PM |
958 | if (p == NULL) { |
959 | /* Leave because rcu_torture_writer is not yet underway */ | |
960 | cur_ops->readunlock(idx); | |
961 | return; | |
962 | } | |
963 | if (p->rtort_mbtest == 0) | |
964 | atomic_inc(&n_rcu_torture_mberror); | |
965 | spin_lock(&rand_lock); | |
0acc512c | 966 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
967 | n_rcu_torture_timers++; |
968 | spin_unlock(&rand_lock); | |
969 | preempt_disable(); | |
970 | pipe_count = p->rtort_pipe_count; | |
971 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
972 | /* Should not happen, but... */ | |
973 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
974 | } | |
91afaf30 PM |
975 | if (pipe_count > 1) |
976 | rcutorture_trace_dump(); | |
dd17c8f7 | 977 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
0729fbf3 PM |
978 | completed = cur_ops->completed() - completed; |
979 | if (completed > RCU_TORTURE_PIPE_LEN) { | |
980 | /* Should not happen, but... */ | |
981 | completed = RCU_TORTURE_PIPE_LEN; | |
982 | } | |
dd17c8f7 | 983 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
984 | preempt_enable(); |
985 | cur_ops->readunlock(idx); | |
986 | } | |
987 | ||
a241ec65 PM |
988 | /* |
989 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
990 | * incrementing the corresponding element of the pipeline array. The | |
991 | * counter in the element should never be greater than 1, otherwise, the | |
992 | * RCU implementation is broken. | |
993 | */ | |
994 | static int | |
995 | rcu_torture_reader(void *arg) | |
996 | { | |
997 | int completed; | |
72e9bb54 | 998 | int idx; |
a241ec65 PM |
999 | DEFINE_RCU_RANDOM(rand); |
1000 | struct rcu_torture *p; | |
1001 | int pipe_count; | |
0729fbf3 | 1002 | struct timer_list t; |
a241ec65 PM |
1003 | |
1004 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 1005 | set_user_nice(current, 19); |
0acc512c | 1006 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1007 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 1008 | |
a241ec65 | 1009 | do { |
0acc512c | 1010 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 1011 | if (!timer_pending(&t)) |
6155fec9 | 1012 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 1013 | } |
72e9bb54 PM |
1014 | idx = cur_ops->readlock(); |
1015 | completed = cur_ops->completed(); | |
632ee200 | 1016 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
1017 | rcu_read_lock_bh_held() || |
1018 | rcu_read_lock_sched_held() || | |
1019 | srcu_read_lock_held(&srcu_ctl)); | |
91afaf30 | 1020 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); |
a241ec65 PM |
1021 | if (p == NULL) { |
1022 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 1023 | cur_ops->readunlock(idx); |
a241ec65 PM |
1024 | schedule_timeout_interruptible(HZ); |
1025 | continue; | |
1026 | } | |
996417d2 PM |
1027 | if (p->rtort_mbtest == 0) |
1028 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 1029 | cur_ops->read_delay(&rand); |
a241ec65 PM |
1030 | preempt_disable(); |
1031 | pipe_count = p->rtort_pipe_count; | |
1032 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
1033 | /* Should not happen, but... */ | |
1034 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
1035 | } | |
91afaf30 PM |
1036 | if (pipe_count > 1) |
1037 | rcutorture_trace_dump(); | |
dd17c8f7 | 1038 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
72e9bb54 | 1039 | completed = cur_ops->completed() - completed; |
a241ec65 PM |
1040 | if (completed > RCU_TORTURE_PIPE_LEN) { |
1041 | /* Should not happen, but... */ | |
1042 | completed = RCU_TORTURE_PIPE_LEN; | |
1043 | } | |
dd17c8f7 | 1044 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 1045 | preempt_enable(); |
72e9bb54 | 1046 | cur_ops->readunlock(idx); |
a241ec65 | 1047 | schedule(); |
c9d557c1 PM |
1048 | rcu_stutter_wait("rcu_torture_reader"); |
1049 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 1050 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 1051 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0acc512c | 1052 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1053 | del_timer_sync(&t); |
c9d557c1 | 1054 | while (!kthread_should_stop()) |
a241ec65 PM |
1055 | schedule_timeout_uninterruptible(1); |
1056 | return 0; | |
1057 | } | |
1058 | ||
1059 | /* | |
1060 | * Create an RCU-torture statistics message in the specified buffer. | |
1061 | */ | |
1062 | static int | |
1063 | rcu_torture_printk(char *page) | |
1064 | { | |
1065 | int cnt = 0; | |
1066 | int cpu; | |
1067 | int i; | |
1068 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1069 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1070 | ||
0a945022 | 1071 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1072 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1073 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
1074 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
1075 | } | |
1076 | } | |
1077 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
1078 | if (pipesummary[i] != 0) | |
1079 | break; | |
1080 | } | |
72e9bb54 | 1081 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1082 | cnt += sprintf(&page[cnt], |
4a298656 | 1083 | "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d " |
67b98dba | 1084 | "rtmbe: %d rtbke: %ld rtbre: %ld " |
8e8be45e | 1085 | "rtbf: %ld rtb: %ld nt: %ld", |
a241ec65 PM |
1086 | rcu_torture_current, |
1087 | rcu_torture_current_version, | |
1088 | list_empty(&rcu_torture_freelist), | |
1089 | atomic_read(&n_rcu_torture_alloc), | |
1090 | atomic_read(&n_rcu_torture_alloc_fail), | |
996417d2 | 1091 | atomic_read(&n_rcu_torture_free), |
0729fbf3 | 1092 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e PM |
1093 | n_rcu_torture_boost_ktrerror, |
1094 | n_rcu_torture_boost_rterror, | |
8e8be45e PM |
1095 | n_rcu_torture_boost_failure, |
1096 | n_rcu_torture_boosts, | |
0729fbf3 | 1097 | n_rcu_torture_timers); |
8e8be45e PM |
1098 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
1099 | n_rcu_torture_boost_ktrerror != 0 || | |
1100 | n_rcu_torture_boost_rterror != 0 || | |
8e8be45e | 1101 | n_rcu_torture_boost_failure != 0) |
996417d2 | 1102 | cnt += sprintf(&page[cnt], " !!!"); |
72e9bb54 | 1103 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
996417d2 | 1104 | if (i > 1) { |
a241ec65 | 1105 | cnt += sprintf(&page[cnt], "!!! "); |
996417d2 | 1106 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 1107 | WARN_ON_ONCE(1); |
996417d2 | 1108 | } |
a241ec65 PM |
1109 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
1110 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) | |
1111 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); | |
72e9bb54 | 1112 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1113 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
72e9bb54 | 1114 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
a241ec65 | 1115 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
72e9bb54 | 1116 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 PM |
1117 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
1118 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { | |
1119 | cnt += sprintf(&page[cnt], " %d", | |
1120 | atomic_read(&rcu_torture_wcount[i])); | |
1121 | } | |
1122 | cnt += sprintf(&page[cnt], "\n"); | |
c8e5b163 | 1123 | if (cur_ops->stats) |
72e9bb54 | 1124 | cnt += cur_ops->stats(&page[cnt]); |
a241ec65 PM |
1125 | return cnt; |
1126 | } | |
1127 | ||
1128 | /* | |
1129 | * Print torture statistics. Caller must ensure that there is only | |
1130 | * one call to this function at a given time!!! This is normally | |
1131 | * accomplished by relying on the module system to only have one copy | |
1132 | * of the module loaded, and then by giving the rcu_torture_stats | |
1133 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1134 | * thread is not running). | |
1135 | */ | |
1136 | static void | |
1137 | rcu_torture_stats_print(void) | |
1138 | { | |
1139 | int cnt; | |
1140 | ||
1141 | cnt = rcu_torture_printk(printk_buf); | |
1142 | printk(KERN_ALERT "%s", printk_buf); | |
1143 | } | |
1144 | ||
1145 | /* | |
1146 | * Periodically prints torture statistics, if periodic statistics printing | |
1147 | * was specified via the stat_interval module parameter. | |
1148 | * | |
1149 | * No need to worry about fullstop here, since this one doesn't reference | |
1150 | * volatile state or register callbacks. | |
1151 | */ | |
1152 | static int | |
1153 | rcu_torture_stats(void *arg) | |
1154 | { | |
1155 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
1156 | do { | |
1157 | schedule_timeout_interruptible(stat_interval * HZ); | |
1158 | rcu_torture_stats_print(); | |
c9d557c1 PM |
1159 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
1160 | } while (!kthread_should_stop()); | |
a241ec65 PM |
1161 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
1162 | return 0; | |
1163 | } | |
1164 | ||
d84f5203 SV |
1165 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
1166 | ||
1167 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
1168 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
1169 | */ | |
b2896d2e | 1170 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 1171 | { |
d84f5203 SV |
1172 | int i; |
1173 | ||
73d0a4b1 | 1174 | cpumask_setall(shuffle_tmp_mask); |
86ef5c9a | 1175 | get_online_cpus(); |
d84f5203 SV |
1176 | |
1177 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
1178 | if (num_online_cpus() == 1) { |
1179 | put_online_cpus(); | |
1180 | return; | |
1181 | } | |
d84f5203 SV |
1182 | |
1183 | if (rcu_idle_cpu != -1) | |
73d0a4b1 | 1184 | cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); |
d84f5203 | 1185 | |
73d0a4b1 | 1186 | set_cpus_allowed_ptr(current, shuffle_tmp_mask); |
d84f5203 | 1187 | |
c8e5b163 | 1188 | if (reader_tasks) { |
d84f5203 SV |
1189 | for (i = 0; i < nrealreaders; i++) |
1190 | if (reader_tasks[i]) | |
f70316da | 1191 | set_cpus_allowed_ptr(reader_tasks[i], |
73d0a4b1 | 1192 | shuffle_tmp_mask); |
d84f5203 SV |
1193 | } |
1194 | ||
c8e5b163 | 1195 | if (fakewriter_tasks) { |
b772e1dd JT |
1196 | for (i = 0; i < nfakewriters; i++) |
1197 | if (fakewriter_tasks[i]) | |
f70316da | 1198 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
73d0a4b1 | 1199 | shuffle_tmp_mask); |
b772e1dd JT |
1200 | } |
1201 | ||
d84f5203 | 1202 | if (writer_task) |
73d0a4b1 | 1203 | set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); |
d84f5203 SV |
1204 | |
1205 | if (stats_task) | |
73d0a4b1 | 1206 | set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); |
d84f5203 SV |
1207 | |
1208 | if (rcu_idle_cpu == -1) | |
1209 | rcu_idle_cpu = num_online_cpus() - 1; | |
1210 | else | |
1211 | rcu_idle_cpu--; | |
1212 | ||
86ef5c9a | 1213 | put_online_cpus(); |
d84f5203 SV |
1214 | } |
1215 | ||
1216 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
1217 | * system to become idle at a time and cut off its timer ticks. This is meant | |
1218 | * to test the support for such tickless idle CPU in RCU. | |
1219 | */ | |
1220 | static int | |
1221 | rcu_torture_shuffle(void *arg) | |
1222 | { | |
1223 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
1224 | do { | |
1225 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
1226 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
1227 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
1228 | } while (!kthread_should_stop()); | |
d84f5203 SV |
1229 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
1230 | return 0; | |
1231 | } | |
1232 | ||
d120f65f PM |
1233 | /* Cause the rcutorture test to "stutter", starting and stopping all |
1234 | * threads periodically. | |
1235 | */ | |
1236 | static int | |
1237 | rcu_torture_stutter(void *arg) | |
1238 | { | |
1239 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
1240 | do { | |
1241 | schedule_timeout_interruptible(stutter * HZ); | |
1242 | stutter_pause_test = 1; | |
c9d557c1 | 1243 | if (!kthread_should_stop()) |
d120f65f PM |
1244 | schedule_timeout_interruptible(stutter * HZ); |
1245 | stutter_pause_test = 0; | |
c9d557c1 PM |
1246 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
1247 | } while (!kthread_should_stop()); | |
d120f65f PM |
1248 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
1249 | return 0; | |
1250 | } | |
1251 | ||
95c38322 | 1252 | static inline void |
8e8be45e | 1253 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag) |
95c38322 | 1254 | { |
b772e1dd JT |
1255 | printk(KERN_ALERT "%s" TORTURE_FLAG |
1256 | "--- %s: nreaders=%d nfakewriters=%d " | |
95c38322 | 1257 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
bf66f18e | 1258 | "shuffle_interval=%d stutter=%d irqreader=%d " |
8e8be45e PM |
1259 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " |
1260 | "test_boost=%d/%d test_boost_interval=%d " | |
d5f546d8 | 1261 | "test_boost_duration=%d shutdown_secs=%d\n", |
b772e1dd | 1262 | torture_type, tag, nrealreaders, nfakewriters, |
d120f65f | 1263 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, |
8e8be45e PM |
1264 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, |
1265 | test_boost, cur_ops->can_boost, | |
d5f546d8 | 1266 | test_boost_interval, test_boost_duration, shutdown_secs); |
95c38322 PM |
1267 | } |
1268 | ||
8e8be45e | 1269 | static struct notifier_block rcutorture_shutdown_nb = { |
343e9099 PM |
1270 | .notifier_call = rcutorture_shutdown_notify, |
1271 | }; | |
1272 | ||
8e8be45e PM |
1273 | static void rcutorture_booster_cleanup(int cpu) |
1274 | { | |
1275 | struct task_struct *t; | |
1276 | ||
1277 | if (boost_tasks[cpu] == NULL) | |
1278 | return; | |
1279 | mutex_lock(&boost_mutex); | |
1280 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task"); | |
1281 | t = boost_tasks[cpu]; | |
1282 | boost_tasks[cpu] = NULL; | |
1283 | mutex_unlock(&boost_mutex); | |
1284 | ||
1285 | /* This must be outside of the mutex, otherwise deadlock! */ | |
1286 | kthread_stop(t); | |
1287 | } | |
1288 | ||
1289 | static int rcutorture_booster_init(int cpu) | |
1290 | { | |
1291 | int retval; | |
1292 | ||
1293 | if (boost_tasks[cpu] != NULL) | |
1294 | return 0; /* Already created, nothing more to do. */ | |
1295 | ||
1296 | /* Don't allow time recalculation while creating a new task. */ | |
1297 | mutex_lock(&boost_mutex); | |
1298 | VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task"); | |
1f288094 ED |
1299 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1300 | cpu_to_node(cpu), | |
1301 | "rcu_torture_boost"); | |
8e8be45e PM |
1302 | if (IS_ERR(boost_tasks[cpu])) { |
1303 | retval = PTR_ERR(boost_tasks[cpu]); | |
1304 | VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed"); | |
1305 | n_rcu_torture_boost_ktrerror++; | |
1306 | boost_tasks[cpu] = NULL; | |
1307 | mutex_unlock(&boost_mutex); | |
1308 | return retval; | |
1309 | } | |
1310 | kthread_bind(boost_tasks[cpu], cpu); | |
1311 | wake_up_process(boost_tasks[cpu]); | |
1312 | mutex_unlock(&boost_mutex); | |
1313 | return 0; | |
1314 | } | |
1315 | ||
d5f546d8 PM |
1316 | /* |
1317 | * Cause the rcutorture test to shutdown the system after the test has | |
1318 | * run for the time specified by the shutdown_secs module parameter. | |
1319 | */ | |
1320 | static int | |
1321 | rcu_torture_shutdown(void *arg) | |
1322 | { | |
1323 | long delta; | |
1324 | unsigned long jiffies_snap; | |
1325 | ||
1326 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started"); | |
1327 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1328 | while (ULONG_CMP_LT(jiffies_snap, shutdown_time) && | |
1329 | !kthread_should_stop()) { | |
1330 | delta = shutdown_time - jiffies_snap; | |
1331 | if (verbose) | |
1332 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
1333 | "rcu_torture_shutdown task: %lu " | |
1334 | "jiffies remaining\n", | |
1335 | torture_type, delta); | |
1336 | schedule_timeout_interruptible(delta); | |
1337 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1338 | } | |
1339 | if (ULONG_CMP_LT(jiffies, shutdown_time)) { | |
1340 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping"); | |
1341 | return 0; | |
1342 | } | |
1343 | ||
1344 | /* OK, shut down the system. */ | |
1345 | ||
1346 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system"); | |
1347 | shutdown_task = NULL; /* Avoid self-kill deadlock. */ | |
1348 | rcu_torture_cleanup(); /* Get the success/failure message. */ | |
1349 | kernel_power_off(); /* Shut down the system. */ | |
1350 | return 0; | |
1351 | } | |
1352 | ||
8e8be45e PM |
1353 | static int rcutorture_cpu_notify(struct notifier_block *self, |
1354 | unsigned long action, void *hcpu) | |
1355 | { | |
1356 | long cpu = (long)hcpu; | |
1357 | ||
1358 | switch (action) { | |
1359 | case CPU_ONLINE: | |
1360 | case CPU_DOWN_FAILED: | |
1361 | (void)rcutorture_booster_init(cpu); | |
1362 | break; | |
1363 | case CPU_DOWN_PREPARE: | |
1364 | rcutorture_booster_cleanup(cpu); | |
1365 | break; | |
1366 | default: | |
1367 | break; | |
1368 | } | |
1369 | return NOTIFY_OK; | |
1370 | } | |
1371 | ||
1372 | static struct notifier_block rcutorture_cpu_nb = { | |
1373 | .notifier_call = rcutorture_cpu_notify, | |
1374 | }; | |
1375 | ||
a241ec65 PM |
1376 | static void |
1377 | rcu_torture_cleanup(void) | |
1378 | { | |
1379 | int i; | |
1380 | ||
343e9099 | 1381 | mutex_lock(&fullstop_mutex); |
4a298656 | 1382 | rcutorture_record_test_transition(); |
c9d557c1 PM |
1383 | if (fullstop == FULLSTOP_SHUTDOWN) { |
1384 | printk(KERN_WARNING /* but going down anyway, so... */ | |
1385 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
343e9099 | 1386 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 1387 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1388 | if (cur_ops->cb_barrier != NULL) |
1389 | cur_ops->cb_barrier(); | |
1390 | return; | |
1391 | } | |
c9d557c1 | 1392 | fullstop = FULLSTOP_RMMOD; |
343e9099 | 1393 | mutex_unlock(&fullstop_mutex); |
8e8be45e | 1394 | unregister_reboot_notifier(&rcutorture_shutdown_nb); |
d120f65f PM |
1395 | if (stutter_task) { |
1396 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1397 | kthread_stop(stutter_task); | |
1398 | } | |
1399 | stutter_task = NULL; | |
c8e5b163 | 1400 | if (shuffler_task) { |
d84f5203 SV |
1401 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1402 | kthread_stop(shuffler_task); | |
73d0a4b1 | 1403 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1404 | } |
1405 | shuffler_task = NULL; | |
1406 | ||
c8e5b163 | 1407 | if (writer_task) { |
a241ec65 PM |
1408 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1409 | kthread_stop(writer_task); | |
1410 | } | |
1411 | writer_task = NULL; | |
1412 | ||
c8e5b163 | 1413 | if (reader_tasks) { |
a241ec65 | 1414 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1415 | if (reader_tasks[i]) { |
a241ec65 PM |
1416 | VERBOSE_PRINTK_STRING( |
1417 | "Stopping rcu_torture_reader task"); | |
1418 | kthread_stop(reader_tasks[i]); | |
1419 | } | |
1420 | reader_tasks[i] = NULL; | |
1421 | } | |
1422 | kfree(reader_tasks); | |
1423 | reader_tasks = NULL; | |
1424 | } | |
1425 | rcu_torture_current = NULL; | |
1426 | ||
c8e5b163 | 1427 | if (fakewriter_tasks) { |
b772e1dd | 1428 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1429 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1430 | VERBOSE_PRINTK_STRING( |
1431 | "Stopping rcu_torture_fakewriter task"); | |
1432 | kthread_stop(fakewriter_tasks[i]); | |
1433 | } | |
1434 | fakewriter_tasks[i] = NULL; | |
1435 | } | |
1436 | kfree(fakewriter_tasks); | |
1437 | fakewriter_tasks = NULL; | |
1438 | } | |
1439 | ||
c8e5b163 | 1440 | if (stats_task) { |
a241ec65 PM |
1441 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1442 | kthread_stop(stats_task); | |
1443 | } | |
1444 | stats_task = NULL; | |
1445 | ||
bf66f18e PM |
1446 | if (fqs_task) { |
1447 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task"); | |
1448 | kthread_stop(fqs_task); | |
1449 | } | |
1450 | fqs_task = NULL; | |
8e8be45e PM |
1451 | if ((test_boost == 1 && cur_ops->can_boost) || |
1452 | test_boost == 2) { | |
1453 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1454 | for_each_possible_cpu(i) | |
1455 | rcutorture_booster_cleanup(i); | |
1456 | } | |
d5f546d8 PM |
1457 | if (shutdown_task != NULL) { |
1458 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task"); | |
1459 | kthread_stop(shutdown_task); | |
1460 | } | |
bf66f18e | 1461 | |
a241ec65 | 1462 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1463 | |
1464 | if (cur_ops->cb_barrier != NULL) | |
1465 | cur_ops->cb_barrier(); | |
a241ec65 | 1466 | |
a241ec65 | 1467 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1468 | |
c8e5b163 | 1469 | if (cur_ops->cleanup) |
72e9bb54 | 1470 | cur_ops->cleanup(); |
95c38322 | 1471 | if (atomic_read(&n_rcu_torture_error)) |
8e8be45e | 1472 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
95c38322 | 1473 | else |
8e8be45e | 1474 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1475 | } |
1476 | ||
6f8bc500 | 1477 | static int __init |
a241ec65 PM |
1478 | rcu_torture_init(void) |
1479 | { | |
1480 | int i; | |
1481 | int cpu; | |
1482 | int firsterr = 0; | |
ade5fb81 | 1483 | static struct rcu_torture_ops *torture_ops[] = |
d9a3da06 | 1484 | { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, |
bdf2a436 | 1485 | &rcu_bh_ops, &rcu_bh_sync_ops, &rcu_bh_expedited_ops, |
804bb837 PM |
1486 | &srcu_ops, &srcu_expedited_ops, |
1487 | &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; | |
a241ec65 | 1488 | |
343e9099 PM |
1489 | mutex_lock(&fullstop_mutex); |
1490 | ||
a241ec65 | 1491 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1492 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1493 | cur_ops = torture_ops[i]; |
ade5fb81 | 1494 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1495 | break; |
72e9bb54 | 1496 | } |
ade5fb81 | 1497 | if (i == ARRAY_SIZE(torture_ops)) { |
cf886c44 | 1498 | printk(KERN_ALERT "rcu-torture: invalid torture type: \"%s\"\n", |
72e9bb54 | 1499 | torture_type); |
cf886c44 PM |
1500 | printk(KERN_ALERT "rcu-torture types:"); |
1501 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
1502 | printk(KERN_ALERT " %s", torture_ops[i]->name); | |
1503 | printk(KERN_ALERT "\n"); | |
343e9099 | 1504 | mutex_unlock(&fullstop_mutex); |
a71fca58 | 1505 | return -EINVAL; |
72e9bb54 | 1506 | } |
bf66f18e PM |
1507 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
1508 | printk(KERN_ALERT "rcu-torture: ->fqs NULL and non-zero " | |
1509 | "fqs_duration, fqs disabled.\n"); | |
1510 | fqs_duration = 0; | |
1511 | } | |
c8e5b163 | 1512 | if (cur_ops->init) |
72e9bb54 PM |
1513 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1514 | ||
a241ec65 PM |
1515 | if (nreaders >= 0) |
1516 | nrealreaders = nreaders; | |
1517 | else | |
1518 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1519 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
c9d557c1 | 1520 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1521 | |
1522 | /* Set up the freelist. */ | |
1523 | ||
1524 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1525 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1526 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1527 | list_add_tail(&rcu_tortures[i].rtort_free, |
1528 | &rcu_torture_freelist); | |
1529 | } | |
1530 | ||
1531 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1532 | ||
1533 | rcu_torture_current = NULL; | |
1534 | rcu_torture_current_version = 0; | |
1535 | atomic_set(&n_rcu_torture_alloc, 0); | |
1536 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1537 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1538 | atomic_set(&n_rcu_torture_mberror, 0); |
1539 | atomic_set(&n_rcu_torture_error, 0); | |
8e8be45e PM |
1540 | n_rcu_torture_boost_ktrerror = 0; |
1541 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
1542 | n_rcu_torture_boost_failure = 0; |
1543 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1544 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1545 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1546 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1547 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1548 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1549 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1550 | } | |
1551 | } | |
1552 | ||
1553 | /* Start up the kthreads. */ | |
1554 | ||
1555 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
1556 | writer_task = kthread_run(rcu_torture_writer, NULL, | |
1557 | "rcu_torture_writer"); | |
1558 | if (IS_ERR(writer_task)) { | |
1559 | firsterr = PTR_ERR(writer_task); | |
1560 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
1561 | writer_task = NULL; | |
1562 | goto unwind; | |
1563 | } | |
b772e1dd | 1564 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1565 | GFP_KERNEL); |
b772e1dd JT |
1566 | if (fakewriter_tasks == NULL) { |
1567 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1568 | firsterr = -ENOMEM; | |
1569 | goto unwind; | |
1570 | } | |
1571 | for (i = 0; i < nfakewriters; i++) { | |
1572 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
1573 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
a71fca58 | 1574 | "rcu_torture_fakewriter"); |
b772e1dd JT |
1575 | if (IS_ERR(fakewriter_tasks[i])) { |
1576 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
1577 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
1578 | fakewriter_tasks[i] = NULL; | |
1579 | goto unwind; | |
1580 | } | |
1581 | } | |
2860aaba | 1582 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1583 | GFP_KERNEL); |
1584 | if (reader_tasks == NULL) { | |
1585 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1586 | firsterr = -ENOMEM; | |
1587 | goto unwind; | |
1588 | } | |
1589 | for (i = 0; i < nrealreaders; i++) { | |
1590 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
1591 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
1592 | "rcu_torture_reader"); | |
1593 | if (IS_ERR(reader_tasks[i])) { | |
1594 | firsterr = PTR_ERR(reader_tasks[i]); | |
1595 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
1596 | reader_tasks[i] = NULL; | |
1597 | goto unwind; | |
1598 | } | |
1599 | } | |
1600 | if (stat_interval > 0) { | |
1601 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
1602 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
1603 | "rcu_torture_stats"); | |
1604 | if (IS_ERR(stats_task)) { | |
1605 | firsterr = PTR_ERR(stats_task); | |
1606 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
1607 | stats_task = NULL; | |
1608 | goto unwind; | |
1609 | } | |
1610 | } | |
d84f5203 SV |
1611 | if (test_no_idle_hz) { |
1612 | rcu_idle_cpu = num_online_cpus() - 1; | |
73d0a4b1 RR |
1613 | |
1614 | if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { | |
1615 | firsterr = -ENOMEM; | |
1616 | VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); | |
1617 | goto unwind; | |
1618 | } | |
1619 | ||
d84f5203 SV |
1620 | /* Create the shuffler thread */ |
1621 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
1622 | "rcu_torture_shuffle"); | |
1623 | if (IS_ERR(shuffler_task)) { | |
73d0a4b1 | 1624 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1625 | firsterr = PTR_ERR(shuffler_task); |
1626 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
1627 | shuffler_task = NULL; | |
1628 | goto unwind; | |
1629 | } | |
1630 | } | |
d120f65f PM |
1631 | if (stutter < 0) |
1632 | stutter = 0; | |
1633 | if (stutter) { | |
1634 | /* Create the stutter thread */ | |
1635 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
1636 | "rcu_torture_stutter"); | |
1637 | if (IS_ERR(stutter_task)) { | |
1638 | firsterr = PTR_ERR(stutter_task); | |
1639 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
1640 | stutter_task = NULL; | |
1641 | goto unwind; | |
1642 | } | |
1643 | } | |
bf66f18e PM |
1644 | if (fqs_duration < 0) |
1645 | fqs_duration = 0; | |
1646 | if (fqs_duration) { | |
1647 | /* Create the stutter thread */ | |
1648 | fqs_task = kthread_run(rcu_torture_fqs, NULL, | |
1649 | "rcu_torture_fqs"); | |
1650 | if (IS_ERR(fqs_task)) { | |
1651 | firsterr = PTR_ERR(fqs_task); | |
1652 | VERBOSE_PRINTK_ERRSTRING("Failed to create fqs"); | |
1653 | fqs_task = NULL; | |
1654 | goto unwind; | |
1655 | } | |
1656 | } | |
8e8be45e PM |
1657 | if (test_boost_interval < 1) |
1658 | test_boost_interval = 1; | |
1659 | if (test_boost_duration < 2) | |
1660 | test_boost_duration = 2; | |
1661 | if ((test_boost == 1 && cur_ops->can_boost) || | |
1662 | test_boost == 2) { | |
1663 | int retval; | |
1664 | ||
1665 | boost_starttime = jiffies + test_boost_interval * HZ; | |
1666 | register_cpu_notifier(&rcutorture_cpu_nb); | |
1667 | for_each_possible_cpu(i) { | |
1668 | if (cpu_is_offline(i)) | |
1669 | continue; /* Heuristic: CPU can go offline. */ | |
1670 | retval = rcutorture_booster_init(i); | |
1671 | if (retval < 0) { | |
1672 | firsterr = retval; | |
1673 | goto unwind; | |
1674 | } | |
1675 | } | |
1676 | } | |
d5f546d8 PM |
1677 | if (shutdown_secs > 0) { |
1678 | shutdown_time = jiffies + shutdown_secs * HZ; | |
1679 | shutdown_task = kthread_run(rcu_torture_shutdown, NULL, | |
1680 | "rcu_torture_shutdown"); | |
1681 | if (IS_ERR(shutdown_task)) { | |
1682 | firsterr = PTR_ERR(shutdown_task); | |
1683 | VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown"); | |
1684 | shutdown_task = NULL; | |
1685 | goto unwind; | |
1686 | } | |
1687 | } | |
8e8be45e | 1688 | register_reboot_notifier(&rcutorture_shutdown_nb); |
4a298656 | 1689 | rcutorture_record_test_transition(); |
343e9099 | 1690 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1691 | return 0; |
1692 | ||
1693 | unwind: | |
343e9099 | 1694 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1695 | rcu_torture_cleanup(); |
1696 | return firsterr; | |
1697 | } | |
1698 | ||
1699 | module_init(rcu_torture_init); | |
1700 | module_exit(rcu_torture_cleanup); |