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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; | |
bb3bf705 PM |
167 | module_param(rcutorture_runnable, int, 0444); |
168 | MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot"); | |
31a72bce | 169 | |
3acf4a9a | 170 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 171 | #define rcu_can_boost() 1 |
3acf4a9a | 172 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 173 | #define rcu_can_boost() 0 |
3acf4a9a | 174 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 175 | |
d5f546d8 | 176 | static unsigned long shutdown_time; /* jiffies to system shutdown. */ |
8e8be45e PM |
177 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
178 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
179 | /* and boost task create/destroy. */ | |
180 | ||
c9d557c1 PM |
181 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
182 | ||
183 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
184 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
185 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
186 | static int fullstop = FULLSTOP_RMMOD; | |
0ddea0ea PM |
187 | /* |
188 | * Protect fullstop transitions and spawning of kthreads. | |
189 | */ | |
190 | static DEFINE_MUTEX(fullstop_mutex); | |
343e9099 | 191 | |
d5f546d8 PM |
192 | /* Forward reference. */ |
193 | static void rcu_torture_cleanup(void); | |
194 | ||
343e9099 | 195 | /* |
c9d557c1 | 196 | * Detect and respond to a system shutdown. |
343e9099 PM |
197 | */ |
198 | static int | |
199 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
200 | unsigned long unused2, void *unused3) | |
201 | { | |
c59ab97e | 202 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 203 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 204 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 PM |
205 | else |
206 | printk(KERN_WARNING /* but going down anyway, so... */ | |
207 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
c59ab97e | 208 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
209 | return NOTIFY_DONE; |
210 | } | |
211 | ||
c9d557c1 PM |
212 | /* |
213 | * Absorb kthreads into a kernel function that won't return, so that | |
214 | * they won't ever access module text or data again. | |
215 | */ | |
216 | static void rcutorture_shutdown_absorb(char *title) | |
217 | { | |
218 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
219 | printk(KERN_NOTICE | |
220 | "rcutorture thread %s parking due to system shutdown\n", | |
221 | title); | |
222 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
223 | } | |
224 | } | |
225 | ||
a241ec65 PM |
226 | /* |
227 | * Allocate an element from the rcu_tortures pool. | |
228 | */ | |
97a41e26 | 229 | static struct rcu_torture * |
a241ec65 PM |
230 | rcu_torture_alloc(void) |
231 | { | |
232 | struct list_head *p; | |
233 | ||
adac1665 | 234 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
235 | if (list_empty(&rcu_torture_freelist)) { |
236 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 237 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
238 | return NULL; |
239 | } | |
240 | atomic_inc(&n_rcu_torture_alloc); | |
241 | p = rcu_torture_freelist.next; | |
242 | list_del_init(p); | |
adac1665 | 243 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
244 | return container_of(p, struct rcu_torture, rtort_free); |
245 | } | |
246 | ||
247 | /* | |
248 | * Free an element to the rcu_tortures pool. | |
249 | */ | |
250 | static void | |
251 | rcu_torture_free(struct rcu_torture *p) | |
252 | { | |
253 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 254 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 255 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 256 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
257 | } |
258 | ||
a241ec65 PM |
259 | struct rcu_random_state { |
260 | unsigned long rrs_state; | |
75cfef32 | 261 | long rrs_count; |
a241ec65 PM |
262 | }; |
263 | ||
264 | #define RCU_RANDOM_MULT 39916801 /* prime */ | |
265 | #define RCU_RANDOM_ADD 479001701 /* prime */ | |
266 | #define RCU_RANDOM_REFRESH 10000 | |
267 | ||
268 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } | |
269 | ||
270 | /* | |
271 | * Crude but fast random-number generator. Uses a linear congruential | |
c17ac855 | 272 | * generator, with occasional help from cpu_clock(). |
a241ec65 | 273 | */ |
75cfef32 | 274 | static unsigned long |
a241ec65 PM |
275 | rcu_random(struct rcu_random_state *rrsp) |
276 | { | |
a241ec65 | 277 | if (--rrsp->rrs_count < 0) { |
c676329a | 278 | rrsp->rrs_state += (unsigned long)local_clock(); |
a241ec65 PM |
279 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
280 | } | |
281 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; | |
282 | return swahw32(rrsp->rrs_state); | |
283 | } | |
284 | ||
d120f65f | 285 | static void |
c9d557c1 | 286 | rcu_stutter_wait(char *title) |
d120f65f | 287 | { |
c9d557c1 | 288 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
289 | if (rcutorture_runnable) |
290 | schedule_timeout_interruptible(1); | |
291 | else | |
3ccf79f4 | 292 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 293 | rcutorture_shutdown_absorb(title); |
343e9099 | 294 | } |
d120f65f PM |
295 | } |
296 | ||
72e9bb54 PM |
297 | /* |
298 | * Operations vector for selecting different types of tests. | |
299 | */ | |
300 | ||
301 | struct rcu_torture_ops { | |
302 | void (*init)(void); | |
303 | void (*cleanup)(void); | |
304 | int (*readlock)(void); | |
0acc512c | 305 | void (*read_delay)(struct rcu_random_state *rrsp); |
72e9bb54 PM |
306 | void (*readunlock)(int idx); |
307 | int (*completed)(void); | |
0acc512c | 308 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 309 | void (*sync)(void); |
2326974d | 310 | void (*cb_barrier)(void); |
bf66f18e | 311 | void (*fqs)(void); |
72e9bb54 | 312 | int (*stats)(char *page); |
0acc512c | 313 | int irq_capable; |
8e8be45e | 314 | int can_boost; |
72e9bb54 PM |
315 | char *name; |
316 | }; | |
a71fca58 PM |
317 | |
318 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
319 | |
320 | /* | |
321 | * Definitions for rcu torture testing. | |
322 | */ | |
323 | ||
a49a4af7 | 324 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
325 | { |
326 | rcu_read_lock(); | |
327 | return 0; | |
328 | } | |
329 | ||
b2896d2e PM |
330 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
331 | { | |
b8d57a76 JT |
332 | const unsigned long shortdelay_us = 200; |
333 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 334 | |
b8d57a76 JT |
335 | /* We want a short delay sometimes to make a reader delay the grace |
336 | * period, and we want a long delay occasionally to trigger | |
337 | * force_quiescent_state. */ | |
b2896d2e | 338 | |
b8d57a76 JT |
339 | if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
340 | mdelay(longdelay_ms); | |
341 | if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) | |
342 | udelay(shortdelay_us); | |
e546f485 LJ |
343 | #ifdef CONFIG_PREEMPT |
344 | if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000))) | |
345 | preempt_schedule(); /* No QS if preempt_disable() in effect */ | |
346 | #endif | |
b2896d2e PM |
347 | } |
348 | ||
a49a4af7 | 349 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
350 | { |
351 | rcu_read_unlock(); | |
352 | } | |
353 | ||
354 | static int rcu_torture_completed(void) | |
355 | { | |
356 | return rcu_batches_completed(); | |
357 | } | |
358 | ||
359 | static void | |
360 | rcu_torture_cb(struct rcu_head *p) | |
361 | { | |
362 | int i; | |
363 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
364 | ||
c9d557c1 | 365 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
366 | /* Test is ending, just drop callbacks on the floor. */ |
367 | /* The next initialization will pick up the pieces. */ | |
368 | return; | |
369 | } | |
370 | i = rp->rtort_pipe_count; | |
371 | if (i > RCU_TORTURE_PIPE_LEN) | |
372 | i = RCU_TORTURE_PIPE_LEN; | |
373 | atomic_inc(&rcu_torture_wcount[i]); | |
374 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
375 | rp->rtort_mbtest = 0; | |
376 | rcu_torture_free(rp); | |
377 | } else | |
0acc512c | 378 | cur_ops->deferred_free(rp); |
72e9bb54 PM |
379 | } |
380 | ||
d9a3da06 PM |
381 | static int rcu_no_completed(void) |
382 | { | |
383 | return 0; | |
384 | } | |
385 | ||
72e9bb54 PM |
386 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
387 | { | |
388 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
389 | } | |
390 | ||
391 | static struct rcu_torture_ops rcu_ops = { | |
0acc512c PM |
392 | .init = NULL, |
393 | .cleanup = NULL, | |
394 | .readlock = rcu_torture_read_lock, | |
395 | .read_delay = rcu_read_delay, | |
396 | .readunlock = rcu_torture_read_unlock, | |
397 | .completed = rcu_torture_completed, | |
398 | .deferred_free = rcu_torture_deferred_free, | |
399 | .sync = synchronize_rcu, | |
400 | .cb_barrier = rcu_barrier, | |
bf66f18e | 401 | .fqs = rcu_force_quiescent_state, |
0acc512c | 402 | .stats = NULL, |
a71fca58 | 403 | .irq_capable = 1, |
8e8be45e | 404 | .can_boost = rcu_can_boost(), |
a71fca58 | 405 | .name = "rcu" |
72e9bb54 PM |
406 | }; |
407 | ||
e3033736 JT |
408 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
409 | { | |
410 | int i; | |
411 | struct rcu_torture *rp; | |
412 | struct rcu_torture *rp1; | |
413 | ||
414 | cur_ops->sync(); | |
415 | list_add(&p->rtort_free, &rcu_torture_removed); | |
416 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
417 | i = rp->rtort_pipe_count; | |
418 | if (i > RCU_TORTURE_PIPE_LEN) | |
419 | i = RCU_TORTURE_PIPE_LEN; | |
420 | atomic_inc(&rcu_torture_wcount[i]); | |
421 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
422 | rp->rtort_mbtest = 0; | |
423 | list_del(&rp->rtort_free); | |
424 | rcu_torture_free(rp); | |
425 | } | |
426 | } | |
427 | } | |
428 | ||
429 | static void rcu_sync_torture_init(void) | |
430 | { | |
431 | INIT_LIST_HEAD(&rcu_torture_removed); | |
432 | } | |
433 | ||
20d2e428 | 434 | static struct rcu_torture_ops rcu_sync_ops = { |
0acc512c PM |
435 | .init = rcu_sync_torture_init, |
436 | .cleanup = NULL, | |
437 | .readlock = rcu_torture_read_lock, | |
438 | .read_delay = rcu_read_delay, | |
439 | .readunlock = rcu_torture_read_unlock, | |
440 | .completed = rcu_torture_completed, | |
441 | .deferred_free = rcu_sync_torture_deferred_free, | |
442 | .sync = synchronize_rcu, | |
443 | .cb_barrier = NULL, | |
bf66f18e | 444 | .fqs = rcu_force_quiescent_state, |
0acc512c PM |
445 | .stats = NULL, |
446 | .irq_capable = 1, | |
8e8be45e | 447 | .can_boost = rcu_can_boost(), |
0acc512c | 448 | .name = "rcu_sync" |
20d2e428 JT |
449 | }; |
450 | ||
d9a3da06 PM |
451 | static struct rcu_torture_ops rcu_expedited_ops = { |
452 | .init = rcu_sync_torture_init, | |
453 | .cleanup = NULL, | |
454 | .readlock = rcu_torture_read_lock, | |
455 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
456 | .readunlock = rcu_torture_read_unlock, | |
457 | .completed = rcu_no_completed, | |
458 | .deferred_free = rcu_sync_torture_deferred_free, | |
459 | .sync = synchronize_rcu_expedited, | |
460 | .cb_barrier = NULL, | |
bf66f18e | 461 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
462 | .stats = NULL, |
463 | .irq_capable = 1, | |
8e8be45e | 464 | .can_boost = rcu_can_boost(), |
d9a3da06 PM |
465 | .name = "rcu_expedited" |
466 | }; | |
467 | ||
c32e0660 PM |
468 | /* |
469 | * Definitions for rcu_bh torture testing. | |
470 | */ | |
471 | ||
a49a4af7 | 472 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
473 | { |
474 | rcu_read_lock_bh(); | |
475 | return 0; | |
476 | } | |
477 | ||
a49a4af7 | 478 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
479 | { |
480 | rcu_read_unlock_bh(); | |
481 | } | |
482 | ||
483 | static int rcu_bh_torture_completed(void) | |
484 | { | |
485 | return rcu_batches_completed_bh(); | |
486 | } | |
487 | ||
488 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
489 | { | |
490 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
491 | } | |
492 | ||
493 | static struct rcu_torture_ops rcu_bh_ops = { | |
0acc512c PM |
494 | .init = NULL, |
495 | .cleanup = NULL, | |
496 | .readlock = rcu_bh_torture_read_lock, | |
497 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
498 | .readunlock = rcu_bh_torture_read_unlock, | |
499 | .completed = rcu_bh_torture_completed, | |
500 | .deferred_free = rcu_bh_torture_deferred_free, | |
bdf2a436 | 501 | .sync = synchronize_rcu_bh, |
0acc512c | 502 | .cb_barrier = rcu_barrier_bh, |
bf66f18e | 503 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
504 | .stats = NULL, |
505 | .irq_capable = 1, | |
506 | .name = "rcu_bh" | |
c32e0660 PM |
507 | }; |
508 | ||
11a14701 | 509 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
0acc512c PM |
510 | .init = rcu_sync_torture_init, |
511 | .cleanup = NULL, | |
512 | .readlock = rcu_bh_torture_read_lock, | |
513 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
514 | .readunlock = rcu_bh_torture_read_unlock, | |
515 | .completed = rcu_bh_torture_completed, | |
516 | .deferred_free = rcu_sync_torture_deferred_free, | |
bdf2a436 | 517 | .sync = synchronize_rcu_bh, |
0acc512c | 518 | .cb_barrier = NULL, |
bf66f18e | 519 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
520 | .stats = NULL, |
521 | .irq_capable = 1, | |
522 | .name = "rcu_bh_sync" | |
11a14701 JT |
523 | }; |
524 | ||
bdf2a436 PM |
525 | static struct rcu_torture_ops rcu_bh_expedited_ops = { |
526 | .init = rcu_sync_torture_init, | |
527 | .cleanup = NULL, | |
528 | .readlock = rcu_bh_torture_read_lock, | |
529 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
530 | .readunlock = rcu_bh_torture_read_unlock, | |
531 | .completed = rcu_bh_torture_completed, | |
532 | .deferred_free = rcu_sync_torture_deferred_free, | |
533 | .sync = synchronize_rcu_bh_expedited, | |
534 | .cb_barrier = NULL, | |
535 | .fqs = rcu_bh_force_quiescent_state, | |
536 | .stats = NULL, | |
537 | .irq_capable = 1, | |
538 | .name = "rcu_bh_expedited" | |
539 | }; | |
540 | ||
b2896d2e PM |
541 | /* |
542 | * Definitions for srcu torture testing. | |
543 | */ | |
544 | ||
545 | static struct srcu_struct srcu_ctl; | |
b2896d2e PM |
546 | |
547 | static void srcu_torture_init(void) | |
548 | { | |
549 | init_srcu_struct(&srcu_ctl); | |
e3033736 | 550 | rcu_sync_torture_init(); |
b2896d2e PM |
551 | } |
552 | ||
553 | static void srcu_torture_cleanup(void) | |
554 | { | |
555 | synchronize_srcu(&srcu_ctl); | |
556 | cleanup_srcu_struct(&srcu_ctl); | |
557 | } | |
558 | ||
012d3ca8 | 559 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
560 | { |
561 | return srcu_read_lock(&srcu_ctl); | |
562 | } | |
563 | ||
564 | static void srcu_read_delay(struct rcu_random_state *rrsp) | |
565 | { | |
566 | long delay; | |
567 | const long uspertick = 1000000 / HZ; | |
568 | const long longdelay = 10; | |
569 | ||
570 | /* We want there to be long-running readers, but not all the time. */ | |
571 | ||
572 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); | |
573 | if (!delay) | |
574 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
575 | else |
576 | rcu_read_delay(rrsp); | |
b2896d2e PM |
577 | } |
578 | ||
012d3ca8 | 579 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
580 | { |
581 | srcu_read_unlock(&srcu_ctl, idx); | |
582 | } | |
583 | ||
584 | static int srcu_torture_completed(void) | |
585 | { | |
586 | return srcu_batches_completed(&srcu_ctl); | |
587 | } | |
588 | ||
b772e1dd JT |
589 | static void srcu_torture_synchronize(void) |
590 | { | |
591 | synchronize_srcu(&srcu_ctl); | |
592 | } | |
593 | ||
b2896d2e PM |
594 | static int srcu_torture_stats(char *page) |
595 | { | |
596 | int cnt = 0; | |
597 | int cpu; | |
598 | int idx = srcu_ctl.completed & 0x1; | |
599 | ||
600 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", | |
601 | torture_type, TORTURE_FLAG, idx); | |
602 | for_each_possible_cpu(cpu) { | |
603 | cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu, | |
604 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], | |
605 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
606 | } | |
607 | cnt += sprintf(&page[cnt], "\n"); | |
608 | return cnt; | |
609 | } | |
610 | ||
611 | static struct rcu_torture_ops srcu_ops = { | |
0acc512c PM |
612 | .init = srcu_torture_init, |
613 | .cleanup = srcu_torture_cleanup, | |
614 | .readlock = srcu_torture_read_lock, | |
615 | .read_delay = srcu_read_delay, | |
616 | .readunlock = srcu_torture_read_unlock, | |
617 | .completed = srcu_torture_completed, | |
618 | .deferred_free = rcu_sync_torture_deferred_free, | |
619 | .sync = srcu_torture_synchronize, | |
620 | .cb_barrier = NULL, | |
621 | .stats = srcu_torture_stats, | |
622 | .name = "srcu" | |
b2896d2e PM |
623 | }; |
624 | ||
804bb837 PM |
625 | static void srcu_torture_synchronize_expedited(void) |
626 | { | |
627 | synchronize_srcu_expedited(&srcu_ctl); | |
628 | } | |
629 | ||
630 | static struct rcu_torture_ops srcu_expedited_ops = { | |
631 | .init = srcu_torture_init, | |
632 | .cleanup = srcu_torture_cleanup, | |
633 | .readlock = srcu_torture_read_lock, | |
634 | .read_delay = srcu_read_delay, | |
635 | .readunlock = srcu_torture_read_unlock, | |
636 | .completed = srcu_torture_completed, | |
637 | .deferred_free = rcu_sync_torture_deferred_free, | |
638 | .sync = srcu_torture_synchronize_expedited, | |
639 | .cb_barrier = NULL, | |
640 | .stats = srcu_torture_stats, | |
641 | .name = "srcu_expedited" | |
642 | }; | |
643 | ||
4b6c2cca JT |
644 | /* |
645 | * Definitions for sched torture testing. | |
646 | */ | |
647 | ||
648 | static int sched_torture_read_lock(void) | |
649 | { | |
650 | preempt_disable(); | |
651 | return 0; | |
652 | } | |
653 | ||
654 | static void sched_torture_read_unlock(int idx) | |
655 | { | |
656 | preempt_enable(); | |
657 | } | |
658 | ||
2326974d PM |
659 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
660 | { | |
661 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
662 | } | |
663 | ||
4b6c2cca | 664 | static struct rcu_torture_ops sched_ops = { |
0acc512c PM |
665 | .init = rcu_sync_torture_init, |
666 | .cleanup = NULL, | |
667 | .readlock = sched_torture_read_lock, | |
668 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
669 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 670 | .completed = rcu_no_completed, |
0acc512c | 671 | .deferred_free = rcu_sched_torture_deferred_free, |
bdf2a436 | 672 | .sync = synchronize_sched, |
0acc512c | 673 | .cb_barrier = rcu_barrier_sched, |
bf66f18e | 674 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
675 | .stats = NULL, |
676 | .irq_capable = 1, | |
677 | .name = "sched" | |
4b6c2cca JT |
678 | }; |
679 | ||
804bb837 | 680 | static struct rcu_torture_ops sched_sync_ops = { |
0acc512c PM |
681 | .init = rcu_sync_torture_init, |
682 | .cleanup = NULL, | |
683 | .readlock = sched_torture_read_lock, | |
684 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
685 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 686 | .completed = rcu_no_completed, |
0acc512c | 687 | .deferred_free = rcu_sync_torture_deferred_free, |
bdf2a436 | 688 | .sync = synchronize_sched, |
0acc512c | 689 | .cb_barrier = NULL, |
bf66f18e | 690 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
691 | .stats = NULL, |
692 | .name = "sched_sync" | |
693 | }; | |
694 | ||
0acc512c PM |
695 | static struct rcu_torture_ops sched_expedited_ops = { |
696 | .init = rcu_sync_torture_init, | |
697 | .cleanup = NULL, | |
698 | .readlock = sched_torture_read_lock, | |
699 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
700 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 701 | .completed = rcu_no_completed, |
0acc512c PM |
702 | .deferred_free = rcu_sync_torture_deferred_free, |
703 | .sync = synchronize_sched_expedited, | |
704 | .cb_barrier = NULL, | |
bf66f18e | 705 | .fqs = rcu_sched_force_quiescent_state, |
969c7921 | 706 | .stats = NULL, |
0acc512c PM |
707 | .irq_capable = 1, |
708 | .name = "sched_expedited" | |
2326974d PM |
709 | }; |
710 | ||
8e8be45e PM |
711 | /* |
712 | * RCU torture priority-boost testing. Runs one real-time thread per | |
713 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
714 | * spinning waiting for them to be invoked. If a given callback takes | |
715 | * too long to be invoked, we assume that priority inversion has occurred. | |
716 | */ | |
717 | ||
718 | struct rcu_boost_inflight { | |
719 | struct rcu_head rcu; | |
720 | int inflight; | |
721 | }; | |
722 | ||
723 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
724 | { | |
725 | struct rcu_boost_inflight *rbip = | |
726 | container_of(head, struct rcu_boost_inflight, rcu); | |
727 | ||
728 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
729 | rbip->inflight = 0; | |
730 | } | |
731 | ||
732 | static int rcu_torture_boost(void *arg) | |
733 | { | |
734 | unsigned long call_rcu_time; | |
735 | unsigned long endtime; | |
736 | unsigned long oldstarttime; | |
737 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
738 | struct sched_param sp; | |
739 | ||
740 | VERBOSE_PRINTK_STRING("rcu_torture_boost started"); | |
741 | ||
742 | /* Set real-time priority. */ | |
743 | sp.sched_priority = 1; | |
744 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
745 | VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!"); | |
746 | n_rcu_torture_boost_rterror++; | |
747 | } | |
748 | ||
561190e3 | 749 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
750 | /* Each pass through the following loop does one boost-test cycle. */ |
751 | do { | |
752 | /* Wait for the next test interval. */ | |
753 | oldstarttime = boost_starttime; | |
93898fb1 | 754 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
8e8be45e PM |
755 | schedule_timeout_uninterruptible(1); |
756 | rcu_stutter_wait("rcu_torture_boost"); | |
757 | if (kthread_should_stop() || | |
758 | fullstop != FULLSTOP_DONTSTOP) | |
759 | goto checkwait; | |
760 | } | |
761 | ||
762 | /* Do one boost-test interval. */ | |
763 | endtime = oldstarttime + test_boost_duration * HZ; | |
764 | call_rcu_time = jiffies; | |
93898fb1 | 765 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e PM |
766 | /* If we don't have a callback in flight, post one. */ |
767 | if (!rbi.inflight) { | |
768 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
769 | rbi.inflight = 1; | |
770 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
771 | if (jiffies - call_rcu_time > | |
772 | test_boost_duration * HZ - HZ / 2) { | |
773 | VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed"); | |
774 | n_rcu_torture_boost_failure++; | |
775 | } | |
776 | call_rcu_time = jiffies; | |
777 | } | |
778 | cond_resched(); | |
779 | rcu_stutter_wait("rcu_torture_boost"); | |
780 | if (kthread_should_stop() || | |
781 | fullstop != FULLSTOP_DONTSTOP) | |
782 | goto checkwait; | |
783 | } | |
784 | ||
785 | /* | |
786 | * Set the start time of the next test interval. | |
787 | * Yes, this is vulnerable to long delays, but such | |
788 | * delays simply cause a false negative for the next | |
789 | * interval. Besides, we are running at RT priority, | |
790 | * so delays should be relatively rare. | |
791 | */ | |
ab8f11e5 PM |
792 | while (oldstarttime == boost_starttime && |
793 | !kthread_should_stop()) { | |
8e8be45e PM |
794 | if (mutex_trylock(&boost_mutex)) { |
795 | boost_starttime = jiffies + | |
796 | test_boost_interval * HZ; | |
797 | n_rcu_torture_boosts++; | |
798 | mutex_unlock(&boost_mutex); | |
799 | break; | |
800 | } | |
801 | schedule_timeout_uninterruptible(1); | |
802 | } | |
803 | ||
804 | /* Go do the stutter. */ | |
805 | checkwait: rcu_stutter_wait("rcu_torture_boost"); | |
806 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
807 | ||
808 | /* Clean up and exit. */ | |
809 | VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping"); | |
810 | rcutorture_shutdown_absorb("rcu_torture_boost"); | |
811 | while (!kthread_should_stop() || rbi.inflight) | |
812 | schedule_timeout_uninterruptible(1); | |
813 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ | |
9d68197c | 814 | destroy_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
815 | return 0; |
816 | } | |
817 | ||
bf66f18e PM |
818 | /* |
819 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
820 | * bursts of calls to force_quiescent_state(), increasing the probability | |
821 | * of occurrence of some important types of race conditions. | |
822 | */ | |
823 | static int | |
824 | rcu_torture_fqs(void *arg) | |
825 | { | |
826 | unsigned long fqs_resume_time; | |
827 | int fqs_burst_remaining; | |
828 | ||
829 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task started"); | |
830 | do { | |
831 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
832 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
833 | !kthread_should_stop()) { | |
bf66f18e PM |
834 | schedule_timeout_interruptible(1); |
835 | } | |
836 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
837 | while (fqs_burst_remaining > 0 && |
838 | !kthread_should_stop()) { | |
bf66f18e PM |
839 | cur_ops->fqs(); |
840 | udelay(fqs_holdoff); | |
841 | fqs_burst_remaining -= fqs_holdoff; | |
842 | } | |
843 | rcu_stutter_wait("rcu_torture_fqs"); | |
844 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
845 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping"); | |
846 | rcutorture_shutdown_absorb("rcu_torture_fqs"); | |
847 | while (!kthread_should_stop()) | |
848 | schedule_timeout_uninterruptible(1); | |
849 | return 0; | |
850 | } | |
851 | ||
a241ec65 PM |
852 | /* |
853 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
854 | * for that pointed to by rcu_torture_current, freeing the old structure | |
855 | * after a series of grace periods (the "pipeline"). | |
856 | */ | |
857 | static int | |
858 | rcu_torture_writer(void *arg) | |
859 | { | |
860 | int i; | |
861 | long oldbatch = rcu_batches_completed(); | |
862 | struct rcu_torture *rp; | |
863 | struct rcu_torture *old_rp; | |
864 | static DEFINE_RCU_RANDOM(rand); | |
865 | ||
866 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
867 | set_user_nice(current, 19); |
868 | ||
a241ec65 PM |
869 | do { |
870 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
871 | rp = rcu_torture_alloc(); |
872 | if (rp == NULL) | |
a241ec65 PM |
873 | continue; |
874 | rp->rtort_pipe_count = 0; | |
875 | udelay(rcu_random(&rand) & 0x3ff); | |
0ddea0ea PM |
876 | old_rp = rcu_dereference_check(rcu_torture_current, |
877 | current == writer_task); | |
996417d2 | 878 | rp->rtort_mbtest = 1; |
a241ec65 | 879 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 880 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 881 | if (old_rp) { |
a241ec65 PM |
882 | i = old_rp->rtort_pipe_count; |
883 | if (i > RCU_TORTURE_PIPE_LEN) | |
884 | i = RCU_TORTURE_PIPE_LEN; | |
885 | atomic_inc(&rcu_torture_wcount[i]); | |
886 | old_rp->rtort_pipe_count++; | |
0acc512c | 887 | cur_ops->deferred_free(old_rp); |
a241ec65 | 888 | } |
4a298656 | 889 | rcutorture_record_progress(++rcu_torture_current_version); |
72e9bb54 | 890 | oldbatch = cur_ops->completed(); |
c9d557c1 PM |
891 | rcu_stutter_wait("rcu_torture_writer"); |
892 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 893 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
894 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
895 | while (!kthread_should_stop()) | |
a241ec65 PM |
896 | schedule_timeout_uninterruptible(1); |
897 | return 0; | |
898 | } | |
899 | ||
b772e1dd JT |
900 | /* |
901 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
902 | * delay between calls. | |
903 | */ | |
904 | static int | |
905 | rcu_torture_fakewriter(void *arg) | |
906 | { | |
907 | DEFINE_RCU_RANDOM(rand); | |
908 | ||
909 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
910 | set_user_nice(current, 19); | |
911 | ||
912 | do { | |
913 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); | |
914 | udelay(rcu_random(&rand) & 0x3ff); | |
915 | cur_ops->sync(); | |
c9d557c1 PM |
916 | rcu_stutter_wait("rcu_torture_fakewriter"); |
917 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
918 | |
919 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
920 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
921 | while (!kthread_should_stop()) | |
b772e1dd JT |
922 | schedule_timeout_uninterruptible(1); |
923 | return 0; | |
924 | } | |
925 | ||
91afaf30 PM |
926 | void rcutorture_trace_dump(void) |
927 | { | |
928 | static atomic_t beenhere = ATOMIC_INIT(0); | |
929 | ||
930 | if (atomic_read(&beenhere)) | |
931 | return; | |
932 | if (atomic_xchg(&beenhere, 1) != 0) | |
933 | return; | |
934 | do_trace_rcu_torture_read(cur_ops->name, (struct rcu_head *)~0UL); | |
935 | ftrace_dump(DUMP_ALL); | |
936 | } | |
937 | ||
0729fbf3 PM |
938 | /* |
939 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
940 | * incrementing the corresponding element of the pipeline array. The | |
941 | * counter in the element should never be greater than 1, otherwise, the | |
942 | * RCU implementation is broken. | |
943 | */ | |
944 | static void rcu_torture_timer(unsigned long unused) | |
945 | { | |
946 | int idx; | |
947 | int completed; | |
948 | static DEFINE_RCU_RANDOM(rand); | |
949 | static DEFINE_SPINLOCK(rand_lock); | |
950 | struct rcu_torture *p; | |
951 | int pipe_count; | |
952 | ||
953 | idx = cur_ops->readlock(); | |
954 | completed = cur_ops->completed(); | |
632ee200 | 955 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
956 | rcu_read_lock_bh_held() || |
957 | rcu_read_lock_sched_held() || | |
958 | srcu_read_lock_held(&srcu_ctl)); | |
91afaf30 | 959 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); |
0729fbf3 PM |
960 | if (p == NULL) { |
961 | /* Leave because rcu_torture_writer is not yet underway */ | |
962 | cur_ops->readunlock(idx); | |
963 | return; | |
964 | } | |
965 | if (p->rtort_mbtest == 0) | |
966 | atomic_inc(&n_rcu_torture_mberror); | |
967 | spin_lock(&rand_lock); | |
0acc512c | 968 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
969 | n_rcu_torture_timers++; |
970 | spin_unlock(&rand_lock); | |
971 | preempt_disable(); | |
972 | pipe_count = p->rtort_pipe_count; | |
973 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
974 | /* Should not happen, but... */ | |
975 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
976 | } | |
91afaf30 PM |
977 | if (pipe_count > 1) |
978 | rcutorture_trace_dump(); | |
dd17c8f7 | 979 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
0729fbf3 PM |
980 | completed = cur_ops->completed() - completed; |
981 | if (completed > RCU_TORTURE_PIPE_LEN) { | |
982 | /* Should not happen, but... */ | |
983 | completed = RCU_TORTURE_PIPE_LEN; | |
984 | } | |
dd17c8f7 | 985 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
986 | preempt_enable(); |
987 | cur_ops->readunlock(idx); | |
988 | } | |
989 | ||
a241ec65 PM |
990 | /* |
991 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
992 | * incrementing the corresponding element of the pipeline array. The | |
993 | * counter in the element should never be greater than 1, otherwise, the | |
994 | * RCU implementation is broken. | |
995 | */ | |
996 | static int | |
997 | rcu_torture_reader(void *arg) | |
998 | { | |
999 | int completed; | |
72e9bb54 | 1000 | int idx; |
a241ec65 PM |
1001 | DEFINE_RCU_RANDOM(rand); |
1002 | struct rcu_torture *p; | |
1003 | int pipe_count; | |
0729fbf3 | 1004 | struct timer_list t; |
a241ec65 PM |
1005 | |
1006 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 1007 | set_user_nice(current, 19); |
0acc512c | 1008 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1009 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 1010 | |
a241ec65 | 1011 | do { |
0acc512c | 1012 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 1013 | if (!timer_pending(&t)) |
6155fec9 | 1014 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 1015 | } |
72e9bb54 PM |
1016 | idx = cur_ops->readlock(); |
1017 | completed = cur_ops->completed(); | |
632ee200 | 1018 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
1019 | rcu_read_lock_bh_held() || |
1020 | rcu_read_lock_sched_held() || | |
1021 | srcu_read_lock_held(&srcu_ctl)); | |
91afaf30 | 1022 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); |
a241ec65 PM |
1023 | if (p == NULL) { |
1024 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 1025 | cur_ops->readunlock(idx); |
a241ec65 PM |
1026 | schedule_timeout_interruptible(HZ); |
1027 | continue; | |
1028 | } | |
996417d2 PM |
1029 | if (p->rtort_mbtest == 0) |
1030 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 1031 | cur_ops->read_delay(&rand); |
a241ec65 PM |
1032 | preempt_disable(); |
1033 | pipe_count = p->rtort_pipe_count; | |
1034 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
1035 | /* Should not happen, but... */ | |
1036 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
1037 | } | |
91afaf30 PM |
1038 | if (pipe_count > 1) |
1039 | rcutorture_trace_dump(); | |
dd17c8f7 | 1040 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
72e9bb54 | 1041 | completed = cur_ops->completed() - completed; |
a241ec65 PM |
1042 | if (completed > RCU_TORTURE_PIPE_LEN) { |
1043 | /* Should not happen, but... */ | |
1044 | completed = RCU_TORTURE_PIPE_LEN; | |
1045 | } | |
dd17c8f7 | 1046 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 1047 | preempt_enable(); |
72e9bb54 | 1048 | cur_ops->readunlock(idx); |
a241ec65 | 1049 | schedule(); |
c9d557c1 PM |
1050 | rcu_stutter_wait("rcu_torture_reader"); |
1051 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 1052 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 1053 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0acc512c | 1054 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1055 | del_timer_sync(&t); |
c9d557c1 | 1056 | while (!kthread_should_stop()) |
a241ec65 PM |
1057 | schedule_timeout_uninterruptible(1); |
1058 | return 0; | |
1059 | } | |
1060 | ||
1061 | /* | |
1062 | * Create an RCU-torture statistics message in the specified buffer. | |
1063 | */ | |
1064 | static int | |
1065 | rcu_torture_printk(char *page) | |
1066 | { | |
1067 | int cnt = 0; | |
1068 | int cpu; | |
1069 | int i; | |
1070 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1071 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1072 | ||
0a945022 | 1073 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1074 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1075 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
1076 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
1077 | } | |
1078 | } | |
1079 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
1080 | if (pipesummary[i] != 0) | |
1081 | break; | |
1082 | } | |
72e9bb54 | 1083 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1084 | cnt += sprintf(&page[cnt], |
4a298656 | 1085 | "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d " |
67b98dba | 1086 | "rtmbe: %d rtbke: %ld rtbre: %ld " |
8e8be45e | 1087 | "rtbf: %ld rtb: %ld nt: %ld", |
a241ec65 PM |
1088 | rcu_torture_current, |
1089 | rcu_torture_current_version, | |
1090 | list_empty(&rcu_torture_freelist), | |
1091 | atomic_read(&n_rcu_torture_alloc), | |
1092 | atomic_read(&n_rcu_torture_alloc_fail), | |
996417d2 | 1093 | atomic_read(&n_rcu_torture_free), |
0729fbf3 | 1094 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e PM |
1095 | n_rcu_torture_boost_ktrerror, |
1096 | n_rcu_torture_boost_rterror, | |
8e8be45e PM |
1097 | n_rcu_torture_boost_failure, |
1098 | n_rcu_torture_boosts, | |
0729fbf3 | 1099 | n_rcu_torture_timers); |
8e8be45e PM |
1100 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
1101 | n_rcu_torture_boost_ktrerror != 0 || | |
1102 | n_rcu_torture_boost_rterror != 0 || | |
8e8be45e | 1103 | n_rcu_torture_boost_failure != 0) |
996417d2 | 1104 | cnt += sprintf(&page[cnt], " !!!"); |
72e9bb54 | 1105 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
996417d2 | 1106 | if (i > 1) { |
a241ec65 | 1107 | cnt += sprintf(&page[cnt], "!!! "); |
996417d2 | 1108 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 1109 | WARN_ON_ONCE(1); |
996417d2 | 1110 | } |
a241ec65 PM |
1111 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
1112 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) | |
1113 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); | |
72e9bb54 | 1114 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1115 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
72e9bb54 | 1116 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
a241ec65 | 1117 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
72e9bb54 | 1118 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 PM |
1119 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
1120 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { | |
1121 | cnt += sprintf(&page[cnt], " %d", | |
1122 | atomic_read(&rcu_torture_wcount[i])); | |
1123 | } | |
1124 | cnt += sprintf(&page[cnt], "\n"); | |
c8e5b163 | 1125 | if (cur_ops->stats) |
72e9bb54 | 1126 | cnt += cur_ops->stats(&page[cnt]); |
a241ec65 PM |
1127 | return cnt; |
1128 | } | |
1129 | ||
1130 | /* | |
1131 | * Print torture statistics. Caller must ensure that there is only | |
1132 | * one call to this function at a given time!!! This is normally | |
1133 | * accomplished by relying on the module system to only have one copy | |
1134 | * of the module loaded, and then by giving the rcu_torture_stats | |
1135 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1136 | * thread is not running). | |
1137 | */ | |
1138 | static void | |
1139 | rcu_torture_stats_print(void) | |
1140 | { | |
1141 | int cnt; | |
1142 | ||
1143 | cnt = rcu_torture_printk(printk_buf); | |
1144 | printk(KERN_ALERT "%s", printk_buf); | |
1145 | } | |
1146 | ||
1147 | /* | |
1148 | * Periodically prints torture statistics, if periodic statistics printing | |
1149 | * was specified via the stat_interval module parameter. | |
1150 | * | |
1151 | * No need to worry about fullstop here, since this one doesn't reference | |
1152 | * volatile state or register callbacks. | |
1153 | */ | |
1154 | static int | |
1155 | rcu_torture_stats(void *arg) | |
1156 | { | |
1157 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
1158 | do { | |
1159 | schedule_timeout_interruptible(stat_interval * HZ); | |
1160 | rcu_torture_stats_print(); | |
c9d557c1 PM |
1161 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
1162 | } while (!kthread_should_stop()); | |
a241ec65 PM |
1163 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
1164 | return 0; | |
1165 | } | |
1166 | ||
d84f5203 SV |
1167 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
1168 | ||
1169 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
1170 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
1171 | */ | |
b2896d2e | 1172 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 1173 | { |
d84f5203 SV |
1174 | int i; |
1175 | ||
73d0a4b1 | 1176 | cpumask_setall(shuffle_tmp_mask); |
86ef5c9a | 1177 | get_online_cpus(); |
d84f5203 SV |
1178 | |
1179 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
1180 | if (num_online_cpus() == 1) { |
1181 | put_online_cpus(); | |
1182 | return; | |
1183 | } | |
d84f5203 SV |
1184 | |
1185 | if (rcu_idle_cpu != -1) | |
73d0a4b1 | 1186 | cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); |
d84f5203 | 1187 | |
73d0a4b1 | 1188 | set_cpus_allowed_ptr(current, shuffle_tmp_mask); |
d84f5203 | 1189 | |
c8e5b163 | 1190 | if (reader_tasks) { |
d84f5203 SV |
1191 | for (i = 0; i < nrealreaders; i++) |
1192 | if (reader_tasks[i]) | |
f70316da | 1193 | set_cpus_allowed_ptr(reader_tasks[i], |
73d0a4b1 | 1194 | shuffle_tmp_mask); |
d84f5203 SV |
1195 | } |
1196 | ||
c8e5b163 | 1197 | if (fakewriter_tasks) { |
b772e1dd JT |
1198 | for (i = 0; i < nfakewriters; i++) |
1199 | if (fakewriter_tasks[i]) | |
f70316da | 1200 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
73d0a4b1 | 1201 | shuffle_tmp_mask); |
b772e1dd JT |
1202 | } |
1203 | ||
d84f5203 | 1204 | if (writer_task) |
73d0a4b1 | 1205 | set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); |
d84f5203 SV |
1206 | |
1207 | if (stats_task) | |
73d0a4b1 | 1208 | set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); |
d84f5203 SV |
1209 | |
1210 | if (rcu_idle_cpu == -1) | |
1211 | rcu_idle_cpu = num_online_cpus() - 1; | |
1212 | else | |
1213 | rcu_idle_cpu--; | |
1214 | ||
86ef5c9a | 1215 | put_online_cpus(); |
d84f5203 SV |
1216 | } |
1217 | ||
1218 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
1219 | * system to become idle at a time and cut off its timer ticks. This is meant | |
1220 | * to test the support for such tickless idle CPU in RCU. | |
1221 | */ | |
1222 | static int | |
1223 | rcu_torture_shuffle(void *arg) | |
1224 | { | |
1225 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
1226 | do { | |
1227 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
1228 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
1229 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
1230 | } while (!kthread_should_stop()); | |
d84f5203 SV |
1231 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
1232 | return 0; | |
1233 | } | |
1234 | ||
d120f65f PM |
1235 | /* Cause the rcutorture test to "stutter", starting and stopping all |
1236 | * threads periodically. | |
1237 | */ | |
1238 | static int | |
1239 | rcu_torture_stutter(void *arg) | |
1240 | { | |
1241 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
1242 | do { | |
1243 | schedule_timeout_interruptible(stutter * HZ); | |
1244 | stutter_pause_test = 1; | |
c9d557c1 | 1245 | if (!kthread_should_stop()) |
d120f65f PM |
1246 | schedule_timeout_interruptible(stutter * HZ); |
1247 | stutter_pause_test = 0; | |
c9d557c1 PM |
1248 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
1249 | } while (!kthread_should_stop()); | |
d120f65f PM |
1250 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
1251 | return 0; | |
1252 | } | |
1253 | ||
95c38322 | 1254 | static inline void |
8e8be45e | 1255 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag) |
95c38322 | 1256 | { |
b772e1dd JT |
1257 | printk(KERN_ALERT "%s" TORTURE_FLAG |
1258 | "--- %s: nreaders=%d nfakewriters=%d " | |
95c38322 | 1259 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
bf66f18e | 1260 | "shuffle_interval=%d stutter=%d irqreader=%d " |
8e8be45e PM |
1261 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " |
1262 | "test_boost=%d/%d test_boost_interval=%d " | |
d5f546d8 | 1263 | "test_boost_duration=%d shutdown_secs=%d\n", |
b772e1dd | 1264 | torture_type, tag, nrealreaders, nfakewriters, |
d120f65f | 1265 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, |
8e8be45e PM |
1266 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, |
1267 | test_boost, cur_ops->can_boost, | |
d5f546d8 | 1268 | test_boost_interval, test_boost_duration, shutdown_secs); |
95c38322 PM |
1269 | } |
1270 | ||
8e8be45e | 1271 | static struct notifier_block rcutorture_shutdown_nb = { |
343e9099 PM |
1272 | .notifier_call = rcutorture_shutdown_notify, |
1273 | }; | |
1274 | ||
8e8be45e PM |
1275 | static void rcutorture_booster_cleanup(int cpu) |
1276 | { | |
1277 | struct task_struct *t; | |
1278 | ||
1279 | if (boost_tasks[cpu] == NULL) | |
1280 | return; | |
1281 | mutex_lock(&boost_mutex); | |
1282 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task"); | |
1283 | t = boost_tasks[cpu]; | |
1284 | boost_tasks[cpu] = NULL; | |
1285 | mutex_unlock(&boost_mutex); | |
1286 | ||
1287 | /* This must be outside of the mutex, otherwise deadlock! */ | |
1288 | kthread_stop(t); | |
1289 | } | |
1290 | ||
1291 | static int rcutorture_booster_init(int cpu) | |
1292 | { | |
1293 | int retval; | |
1294 | ||
1295 | if (boost_tasks[cpu] != NULL) | |
1296 | return 0; /* Already created, nothing more to do. */ | |
1297 | ||
1298 | /* Don't allow time recalculation while creating a new task. */ | |
1299 | mutex_lock(&boost_mutex); | |
1300 | VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task"); | |
1f288094 ED |
1301 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1302 | cpu_to_node(cpu), | |
1303 | "rcu_torture_boost"); | |
8e8be45e PM |
1304 | if (IS_ERR(boost_tasks[cpu])) { |
1305 | retval = PTR_ERR(boost_tasks[cpu]); | |
1306 | VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed"); | |
1307 | n_rcu_torture_boost_ktrerror++; | |
1308 | boost_tasks[cpu] = NULL; | |
1309 | mutex_unlock(&boost_mutex); | |
1310 | return retval; | |
1311 | } | |
1312 | kthread_bind(boost_tasks[cpu], cpu); | |
1313 | wake_up_process(boost_tasks[cpu]); | |
1314 | mutex_unlock(&boost_mutex); | |
1315 | return 0; | |
1316 | } | |
1317 | ||
d5f546d8 PM |
1318 | /* |
1319 | * Cause the rcutorture test to shutdown the system after the test has | |
1320 | * run for the time specified by the shutdown_secs module parameter. | |
1321 | */ | |
1322 | static int | |
1323 | rcu_torture_shutdown(void *arg) | |
1324 | { | |
1325 | long delta; | |
1326 | unsigned long jiffies_snap; | |
1327 | ||
1328 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started"); | |
1329 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1330 | while (ULONG_CMP_LT(jiffies_snap, shutdown_time) && | |
1331 | !kthread_should_stop()) { | |
1332 | delta = shutdown_time - jiffies_snap; | |
1333 | if (verbose) | |
1334 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
1335 | "rcu_torture_shutdown task: %lu " | |
1336 | "jiffies remaining\n", | |
1337 | torture_type, delta); | |
1338 | schedule_timeout_interruptible(delta); | |
1339 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1340 | } | |
1341 | if (ULONG_CMP_LT(jiffies, shutdown_time)) { | |
1342 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping"); | |
1343 | return 0; | |
1344 | } | |
1345 | ||
1346 | /* OK, shut down the system. */ | |
1347 | ||
1348 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system"); | |
1349 | shutdown_task = NULL; /* Avoid self-kill deadlock. */ | |
1350 | rcu_torture_cleanup(); /* Get the success/failure message. */ | |
1351 | kernel_power_off(); /* Shut down the system. */ | |
1352 | return 0; | |
1353 | } | |
1354 | ||
8e8be45e PM |
1355 | static int rcutorture_cpu_notify(struct notifier_block *self, |
1356 | unsigned long action, void *hcpu) | |
1357 | { | |
1358 | long cpu = (long)hcpu; | |
1359 | ||
1360 | switch (action) { | |
1361 | case CPU_ONLINE: | |
1362 | case CPU_DOWN_FAILED: | |
1363 | (void)rcutorture_booster_init(cpu); | |
1364 | break; | |
1365 | case CPU_DOWN_PREPARE: | |
1366 | rcutorture_booster_cleanup(cpu); | |
1367 | break; | |
1368 | default: | |
1369 | break; | |
1370 | } | |
1371 | return NOTIFY_OK; | |
1372 | } | |
1373 | ||
1374 | static struct notifier_block rcutorture_cpu_nb = { | |
1375 | .notifier_call = rcutorture_cpu_notify, | |
1376 | }; | |
1377 | ||
a241ec65 PM |
1378 | static void |
1379 | rcu_torture_cleanup(void) | |
1380 | { | |
1381 | int i; | |
1382 | ||
343e9099 | 1383 | mutex_lock(&fullstop_mutex); |
4a298656 | 1384 | rcutorture_record_test_transition(); |
c9d557c1 PM |
1385 | if (fullstop == FULLSTOP_SHUTDOWN) { |
1386 | printk(KERN_WARNING /* but going down anyway, so... */ | |
1387 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
343e9099 | 1388 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 1389 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1390 | if (cur_ops->cb_barrier != NULL) |
1391 | cur_ops->cb_barrier(); | |
1392 | return; | |
1393 | } | |
c9d557c1 | 1394 | fullstop = FULLSTOP_RMMOD; |
343e9099 | 1395 | mutex_unlock(&fullstop_mutex); |
8e8be45e | 1396 | unregister_reboot_notifier(&rcutorture_shutdown_nb); |
d120f65f PM |
1397 | if (stutter_task) { |
1398 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1399 | kthread_stop(stutter_task); | |
1400 | } | |
1401 | stutter_task = NULL; | |
c8e5b163 | 1402 | if (shuffler_task) { |
d84f5203 SV |
1403 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1404 | kthread_stop(shuffler_task); | |
73d0a4b1 | 1405 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1406 | } |
1407 | shuffler_task = NULL; | |
1408 | ||
c8e5b163 | 1409 | if (writer_task) { |
a241ec65 PM |
1410 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1411 | kthread_stop(writer_task); | |
1412 | } | |
1413 | writer_task = NULL; | |
1414 | ||
c8e5b163 | 1415 | if (reader_tasks) { |
a241ec65 | 1416 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1417 | if (reader_tasks[i]) { |
a241ec65 PM |
1418 | VERBOSE_PRINTK_STRING( |
1419 | "Stopping rcu_torture_reader task"); | |
1420 | kthread_stop(reader_tasks[i]); | |
1421 | } | |
1422 | reader_tasks[i] = NULL; | |
1423 | } | |
1424 | kfree(reader_tasks); | |
1425 | reader_tasks = NULL; | |
1426 | } | |
1427 | rcu_torture_current = NULL; | |
1428 | ||
c8e5b163 | 1429 | if (fakewriter_tasks) { |
b772e1dd | 1430 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1431 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1432 | VERBOSE_PRINTK_STRING( |
1433 | "Stopping rcu_torture_fakewriter task"); | |
1434 | kthread_stop(fakewriter_tasks[i]); | |
1435 | } | |
1436 | fakewriter_tasks[i] = NULL; | |
1437 | } | |
1438 | kfree(fakewriter_tasks); | |
1439 | fakewriter_tasks = NULL; | |
1440 | } | |
1441 | ||
c8e5b163 | 1442 | if (stats_task) { |
a241ec65 PM |
1443 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1444 | kthread_stop(stats_task); | |
1445 | } | |
1446 | stats_task = NULL; | |
1447 | ||
bf66f18e PM |
1448 | if (fqs_task) { |
1449 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task"); | |
1450 | kthread_stop(fqs_task); | |
1451 | } | |
1452 | fqs_task = NULL; | |
8e8be45e PM |
1453 | if ((test_boost == 1 && cur_ops->can_boost) || |
1454 | test_boost == 2) { | |
1455 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1456 | for_each_possible_cpu(i) | |
1457 | rcutorture_booster_cleanup(i); | |
1458 | } | |
d5f546d8 PM |
1459 | if (shutdown_task != NULL) { |
1460 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task"); | |
1461 | kthread_stop(shutdown_task); | |
1462 | } | |
bf66f18e | 1463 | |
a241ec65 | 1464 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1465 | |
1466 | if (cur_ops->cb_barrier != NULL) | |
1467 | cur_ops->cb_barrier(); | |
a241ec65 | 1468 | |
a241ec65 | 1469 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1470 | |
c8e5b163 | 1471 | if (cur_ops->cleanup) |
72e9bb54 | 1472 | cur_ops->cleanup(); |
95c38322 | 1473 | if (atomic_read(&n_rcu_torture_error)) |
8e8be45e | 1474 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
95c38322 | 1475 | else |
8e8be45e | 1476 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1477 | } |
1478 | ||
6f8bc500 | 1479 | static int __init |
a241ec65 PM |
1480 | rcu_torture_init(void) |
1481 | { | |
1482 | int i; | |
1483 | int cpu; | |
1484 | int firsterr = 0; | |
ade5fb81 | 1485 | static struct rcu_torture_ops *torture_ops[] = |
d9a3da06 | 1486 | { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, |
bdf2a436 | 1487 | &rcu_bh_ops, &rcu_bh_sync_ops, &rcu_bh_expedited_ops, |
804bb837 PM |
1488 | &srcu_ops, &srcu_expedited_ops, |
1489 | &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; | |
a241ec65 | 1490 | |
343e9099 PM |
1491 | mutex_lock(&fullstop_mutex); |
1492 | ||
a241ec65 | 1493 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1494 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1495 | cur_ops = torture_ops[i]; |
ade5fb81 | 1496 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1497 | break; |
72e9bb54 | 1498 | } |
ade5fb81 | 1499 | if (i == ARRAY_SIZE(torture_ops)) { |
cf886c44 | 1500 | printk(KERN_ALERT "rcu-torture: invalid torture type: \"%s\"\n", |
72e9bb54 | 1501 | torture_type); |
cf886c44 PM |
1502 | printk(KERN_ALERT "rcu-torture types:"); |
1503 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
1504 | printk(KERN_ALERT " %s", torture_ops[i]->name); | |
1505 | printk(KERN_ALERT "\n"); | |
343e9099 | 1506 | mutex_unlock(&fullstop_mutex); |
a71fca58 | 1507 | return -EINVAL; |
72e9bb54 | 1508 | } |
bf66f18e PM |
1509 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
1510 | printk(KERN_ALERT "rcu-torture: ->fqs NULL and non-zero " | |
1511 | "fqs_duration, fqs disabled.\n"); | |
1512 | fqs_duration = 0; | |
1513 | } | |
c8e5b163 | 1514 | if (cur_ops->init) |
72e9bb54 PM |
1515 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1516 | ||
a241ec65 PM |
1517 | if (nreaders >= 0) |
1518 | nrealreaders = nreaders; | |
1519 | else | |
1520 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1521 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
c9d557c1 | 1522 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1523 | |
1524 | /* Set up the freelist. */ | |
1525 | ||
1526 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1527 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1528 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1529 | list_add_tail(&rcu_tortures[i].rtort_free, |
1530 | &rcu_torture_freelist); | |
1531 | } | |
1532 | ||
1533 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1534 | ||
1535 | rcu_torture_current = NULL; | |
1536 | rcu_torture_current_version = 0; | |
1537 | atomic_set(&n_rcu_torture_alloc, 0); | |
1538 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1539 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1540 | atomic_set(&n_rcu_torture_mberror, 0); |
1541 | atomic_set(&n_rcu_torture_error, 0); | |
8e8be45e PM |
1542 | n_rcu_torture_boost_ktrerror = 0; |
1543 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
1544 | n_rcu_torture_boost_failure = 0; |
1545 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1546 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1547 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1548 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1549 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1550 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1551 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1552 | } | |
1553 | } | |
1554 | ||
1555 | /* Start up the kthreads. */ | |
1556 | ||
1557 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
1558 | writer_task = kthread_run(rcu_torture_writer, NULL, | |
1559 | "rcu_torture_writer"); | |
1560 | if (IS_ERR(writer_task)) { | |
1561 | firsterr = PTR_ERR(writer_task); | |
1562 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
1563 | writer_task = NULL; | |
1564 | goto unwind; | |
1565 | } | |
b772e1dd | 1566 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 1567 | GFP_KERNEL); |
b772e1dd JT |
1568 | if (fakewriter_tasks == NULL) { |
1569 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1570 | firsterr = -ENOMEM; | |
1571 | goto unwind; | |
1572 | } | |
1573 | for (i = 0; i < nfakewriters; i++) { | |
1574 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
1575 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
a71fca58 | 1576 | "rcu_torture_fakewriter"); |
b772e1dd JT |
1577 | if (IS_ERR(fakewriter_tasks[i])) { |
1578 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
1579 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
1580 | fakewriter_tasks[i] = NULL; | |
1581 | goto unwind; | |
1582 | } | |
1583 | } | |
2860aaba | 1584 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
1585 | GFP_KERNEL); |
1586 | if (reader_tasks == NULL) { | |
1587 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
1588 | firsterr = -ENOMEM; | |
1589 | goto unwind; | |
1590 | } | |
1591 | for (i = 0; i < nrealreaders; i++) { | |
1592 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
1593 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
1594 | "rcu_torture_reader"); | |
1595 | if (IS_ERR(reader_tasks[i])) { | |
1596 | firsterr = PTR_ERR(reader_tasks[i]); | |
1597 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
1598 | reader_tasks[i] = NULL; | |
1599 | goto unwind; | |
1600 | } | |
1601 | } | |
1602 | if (stat_interval > 0) { | |
1603 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
1604 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
1605 | "rcu_torture_stats"); | |
1606 | if (IS_ERR(stats_task)) { | |
1607 | firsterr = PTR_ERR(stats_task); | |
1608 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
1609 | stats_task = NULL; | |
1610 | goto unwind; | |
1611 | } | |
1612 | } | |
d84f5203 SV |
1613 | if (test_no_idle_hz) { |
1614 | rcu_idle_cpu = num_online_cpus() - 1; | |
73d0a4b1 RR |
1615 | |
1616 | if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { | |
1617 | firsterr = -ENOMEM; | |
1618 | VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); | |
1619 | goto unwind; | |
1620 | } | |
1621 | ||
d84f5203 SV |
1622 | /* Create the shuffler thread */ |
1623 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
1624 | "rcu_torture_shuffle"); | |
1625 | if (IS_ERR(shuffler_task)) { | |
73d0a4b1 | 1626 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1627 | firsterr = PTR_ERR(shuffler_task); |
1628 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
1629 | shuffler_task = NULL; | |
1630 | goto unwind; | |
1631 | } | |
1632 | } | |
d120f65f PM |
1633 | if (stutter < 0) |
1634 | stutter = 0; | |
1635 | if (stutter) { | |
1636 | /* Create the stutter thread */ | |
1637 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
1638 | "rcu_torture_stutter"); | |
1639 | if (IS_ERR(stutter_task)) { | |
1640 | firsterr = PTR_ERR(stutter_task); | |
1641 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
1642 | stutter_task = NULL; | |
1643 | goto unwind; | |
1644 | } | |
1645 | } | |
bf66f18e PM |
1646 | if (fqs_duration < 0) |
1647 | fqs_duration = 0; | |
1648 | if (fqs_duration) { | |
1649 | /* Create the stutter thread */ | |
1650 | fqs_task = kthread_run(rcu_torture_fqs, NULL, | |
1651 | "rcu_torture_fqs"); | |
1652 | if (IS_ERR(fqs_task)) { | |
1653 | firsterr = PTR_ERR(fqs_task); | |
1654 | VERBOSE_PRINTK_ERRSTRING("Failed to create fqs"); | |
1655 | fqs_task = NULL; | |
1656 | goto unwind; | |
1657 | } | |
1658 | } | |
8e8be45e PM |
1659 | if (test_boost_interval < 1) |
1660 | test_boost_interval = 1; | |
1661 | if (test_boost_duration < 2) | |
1662 | test_boost_duration = 2; | |
1663 | if ((test_boost == 1 && cur_ops->can_boost) || | |
1664 | test_boost == 2) { | |
1665 | int retval; | |
1666 | ||
1667 | boost_starttime = jiffies + test_boost_interval * HZ; | |
1668 | register_cpu_notifier(&rcutorture_cpu_nb); | |
1669 | for_each_possible_cpu(i) { | |
1670 | if (cpu_is_offline(i)) | |
1671 | continue; /* Heuristic: CPU can go offline. */ | |
1672 | retval = rcutorture_booster_init(i); | |
1673 | if (retval < 0) { | |
1674 | firsterr = retval; | |
1675 | goto unwind; | |
1676 | } | |
1677 | } | |
1678 | } | |
d5f546d8 PM |
1679 | if (shutdown_secs > 0) { |
1680 | shutdown_time = jiffies + shutdown_secs * HZ; | |
1681 | shutdown_task = kthread_run(rcu_torture_shutdown, NULL, | |
1682 | "rcu_torture_shutdown"); | |
1683 | if (IS_ERR(shutdown_task)) { | |
1684 | firsterr = PTR_ERR(shutdown_task); | |
1685 | VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown"); | |
1686 | shutdown_task = NULL; | |
1687 | goto unwind; | |
1688 | } | |
1689 | } | |
8e8be45e | 1690 | register_reboot_notifier(&rcutorture_shutdown_nb); |
4a298656 | 1691 | rcutorture_record_test_transition(); |
343e9099 | 1692 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1693 | return 0; |
1694 | ||
1695 | unwind: | |
343e9099 | 1696 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
1697 | rcu_torture_cleanup(); |
1698 | return firsterr; | |
1699 | } | |
1700 | ||
1701 | module_init(rcu_torture_init); | |
1702 | module_exit(rcu_torture_cleanup); |