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"); | |
5cf05ad7 | 52 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>"); |
a241ec65 | 53 | |
4802211c | 54 | static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ |
b772e1dd | 55 | static int nfakewriters = 4; /* # fake writer threads */ |
d84f5203 | 56 | static int stat_interval; /* Interval between stats, in seconds. */ |
a241ec65 | 57 | /* Defaults to "only at end of test". */ |
d8e8ed95 RR |
58 | static bool verbose; /* Print more debug info. */ |
59 | static bool test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ | |
d120f65f PM |
60 | static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ |
61 | static int stutter = 5; /* Start/stop testing interval (in sec) */ | |
0729fbf3 | 62 | static int irqreader = 1; /* RCU readers from irq (timers). */ |
d5f546d8 PM |
63 | static int fqs_duration; /* Duration of bursts (us), 0 to disable. */ |
64 | static int fqs_holdoff; /* Hold time within burst (us). */ | |
bf66f18e | 65 | static int fqs_stutter = 3; /* Wait time between bursts (s). */ |
fae4b54f | 66 | static int n_barrier_cbs; /* Number of callbacks to test RCU barriers. */ |
b58bdcca | 67 | static int onoff_interval; /* Wait time between CPU hotplugs, 0=disable. */ |
9b9ec9b9 | 68 | static int onoff_holdoff; /* Seconds after boot before CPU hotplugs. */ |
d5f546d8 | 69 | static int shutdown_secs; /* Shutdown time (s). <=0 for no shutdown. */ |
c13f3757 PM |
70 | static int stall_cpu; /* CPU-stall duration (s). 0 for no stall. */ |
71 | static int stall_cpu_holdoff = 10; /* Time to wait until stall (s). */ | |
8e8be45e PM |
72 | static int test_boost = 1; /* Test RCU prio boost: 0=no, 1=maybe, 2=yes. */ |
73 | static int test_boost_interval = 7; /* Interval between boost tests, seconds. */ | |
74 | static int test_boost_duration = 4; /* Duration of each boost test, seconds. */ | |
20d2e428 | 75 | static char *torture_type = "rcu"; /* What RCU implementation to torture. */ |
a241ec65 | 76 | |
d6ad6711 | 77 | module_param(nreaders, int, 0444); |
a241ec65 | 78 | MODULE_PARM_DESC(nreaders, "Number of RCU reader threads"); |
d6ad6711 | 79 | module_param(nfakewriters, int, 0444); |
b772e1dd | 80 | MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads"); |
3721bc1d | 81 | module_param(stat_interval, int, 0644); |
a241ec65 | 82 | MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s"); |
d6ad6711 | 83 | module_param(verbose, bool, 0444); |
a241ec65 | 84 | MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s"); |
d6ad6711 | 85 | module_param(test_no_idle_hz, bool, 0444); |
d84f5203 | 86 | MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs"); |
d6ad6711 | 87 | module_param(shuffle_interval, int, 0444); |
d84f5203 | 88 | MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles"); |
d120f65f PM |
89 | module_param(stutter, int, 0444); |
90 | MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test"); | |
0729fbf3 PM |
91 | module_param(irqreader, int, 0444); |
92 | MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers"); | |
bf66f18e PM |
93 | module_param(fqs_duration, int, 0444); |
94 | MODULE_PARM_DESC(fqs_duration, "Duration of fqs bursts (us)"); | |
95 | module_param(fqs_holdoff, int, 0444); | |
96 | MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)"); | |
97 | module_param(fqs_stutter, int, 0444); | |
98 | MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)"); | |
fae4b54f PM |
99 | module_param(n_barrier_cbs, int, 0444); |
100 | MODULE_PARM_DESC(n_barrier_cbs, "# of callbacks/kthreads for barrier testing"); | |
b58bdcca PM |
101 | module_param(onoff_interval, int, 0444); |
102 | MODULE_PARM_DESC(onoff_interval, "Time between CPU hotplugs (s), 0=disable"); | |
9b9ec9b9 PM |
103 | module_param(onoff_holdoff, int, 0444); |
104 | MODULE_PARM_DESC(onoff_holdoff, "Time after boot before CPU hotplugs (s)"); | |
d5f546d8 PM |
105 | module_param(shutdown_secs, int, 0444); |
106 | MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), zero to disable."); | |
c13f3757 PM |
107 | module_param(stall_cpu, int, 0444); |
108 | MODULE_PARM_DESC(stall_cpu, "Stall duration (s), zero to disable."); | |
109 | module_param(stall_cpu_holdoff, int, 0444); | |
110 | MODULE_PARM_DESC(stall_cpu_holdoff, "Time to wait before starting stall (s)."); | |
8e8be45e PM |
111 | module_param(test_boost, int, 0444); |
112 | MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); | |
113 | module_param(test_boost_interval, int, 0444); | |
114 | MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds."); | |
115 | module_param(test_boost_duration, int, 0444); | |
116 | MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds."); | |
d6ad6711 | 117 | module_param(torture_type, charp, 0444); |
b2896d2e | 118 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); |
72e9bb54 PM |
119 | |
120 | #define TORTURE_FLAG "-torture:" | |
a241ec65 | 121 | #define PRINTK_STRING(s) \ |
72e9bb54 | 122 | do { printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 123 | #define VERBOSE_PRINTK_STRING(s) \ |
72e9bb54 | 124 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
a241ec65 | 125 | #define VERBOSE_PRINTK_ERRSTRING(s) \ |
72e9bb54 | 126 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) |
a241ec65 PM |
127 | |
128 | static char printk_buf[4096]; | |
129 | ||
130 | static int nrealreaders; | |
131 | static struct task_struct *writer_task; | |
b772e1dd | 132 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
133 | static struct task_struct **reader_tasks; |
134 | static struct task_struct *stats_task; | |
d84f5203 | 135 | static struct task_struct *shuffler_task; |
d120f65f | 136 | static struct task_struct *stutter_task; |
bf66f18e | 137 | static struct task_struct *fqs_task; |
8e8be45e | 138 | static struct task_struct *boost_tasks[NR_CPUS]; |
d5f546d8 | 139 | static struct task_struct *shutdown_task; |
b58bdcca PM |
140 | #ifdef CONFIG_HOTPLUG_CPU |
141 | static struct task_struct *onoff_task; | |
142 | #endif /* #ifdef CONFIG_HOTPLUG_CPU */ | |
c13f3757 | 143 | static struct task_struct *stall_task; |
fae4b54f PM |
144 | static struct task_struct **barrier_cbs_tasks; |
145 | static struct task_struct *barrier_task; | |
a241ec65 PM |
146 | |
147 | #define RCU_TORTURE_PIPE_LEN 10 | |
148 | ||
149 | struct rcu_torture { | |
150 | struct rcu_head rtort_rcu; | |
151 | int rtort_pipe_count; | |
152 | struct list_head rtort_free; | |
996417d2 | 153 | int rtort_mbtest; |
a241ec65 PM |
154 | }; |
155 | ||
a241ec65 | 156 | static LIST_HEAD(rcu_torture_freelist); |
0ddea0ea | 157 | static struct rcu_torture __rcu *rcu_torture_current; |
4a298656 | 158 | static unsigned long rcu_torture_current_version; |
a241ec65 PM |
159 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
160 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
161 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = | |
162 | { 0 }; | |
163 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = | |
164 | { 0 }; | |
165 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; | |
b2896d2e PM |
166 | static atomic_t n_rcu_torture_alloc; |
167 | static atomic_t n_rcu_torture_alloc_fail; | |
168 | static atomic_t n_rcu_torture_free; | |
169 | static atomic_t n_rcu_torture_mberror; | |
170 | static atomic_t n_rcu_torture_error; | |
fae4b54f | 171 | static long n_rcu_torture_barrier_error; |
8e8be45e PM |
172 | static long n_rcu_torture_boost_ktrerror; |
173 | static long n_rcu_torture_boost_rterror; | |
8e8be45e PM |
174 | static long n_rcu_torture_boost_failure; |
175 | static long n_rcu_torture_boosts; | |
a71fca58 | 176 | static long n_rcu_torture_timers; |
b58bdcca PM |
177 | static long n_offline_attempts; |
178 | static long n_offline_successes; | |
179 | static long n_online_attempts; | |
180 | static long n_online_successes; | |
fae4b54f PM |
181 | static long n_barrier_attempts; |
182 | static long n_barrier_successes; | |
e3033736 | 183 | static struct list_head rcu_torture_removed; |
73d0a4b1 | 184 | static cpumask_var_t shuffle_tmp_mask; |
a241ec65 | 185 | |
a71fca58 | 186 | static int stutter_pause_test; |
d120f65f | 187 | |
31a72bce PM |
188 | #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) |
189 | #define RCUTORTURE_RUNNABLE_INIT 1 | |
190 | #else | |
191 | #define RCUTORTURE_RUNNABLE_INIT 0 | |
192 | #endif | |
193 | int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; | |
bb3bf705 PM |
194 | module_param(rcutorture_runnable, int, 0444); |
195 | MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot"); | |
31a72bce | 196 | |
3acf4a9a | 197 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 198 | #define rcu_can_boost() 1 |
3acf4a9a | 199 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 200 | #define rcu_can_boost() 0 |
3acf4a9a | 201 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 202 | |
d5f546d8 | 203 | static unsigned long shutdown_time; /* jiffies to system shutdown. */ |
8e8be45e PM |
204 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
205 | DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ | |
206 | /* and boost task create/destroy. */ | |
fae4b54f | 207 | static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */ |
c6ebcbb6 | 208 | static bool barrier_phase; /* Test phase. */ |
fae4b54f PM |
209 | static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */ |
210 | static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */ | |
211 | static DECLARE_WAIT_QUEUE_HEAD(barrier_wq); | |
8e8be45e | 212 | |
c9d557c1 PM |
213 | /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ |
214 | ||
215 | #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ | |
216 | #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ | |
217 | #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ | |
218 | static int fullstop = FULLSTOP_RMMOD; | |
0ddea0ea PM |
219 | /* |
220 | * Protect fullstop transitions and spawning of kthreads. | |
221 | */ | |
222 | static DEFINE_MUTEX(fullstop_mutex); | |
343e9099 | 223 | |
d5f546d8 PM |
224 | /* Forward reference. */ |
225 | static void rcu_torture_cleanup(void); | |
226 | ||
343e9099 | 227 | /* |
c9d557c1 | 228 | * Detect and respond to a system shutdown. |
343e9099 PM |
229 | */ |
230 | static int | |
231 | rcutorture_shutdown_notify(struct notifier_block *unused1, | |
232 | unsigned long unused2, void *unused3) | |
233 | { | |
c59ab97e | 234 | mutex_lock(&fullstop_mutex); |
c9d557c1 | 235 | if (fullstop == FULLSTOP_DONTSTOP) |
c59ab97e | 236 | fullstop = FULLSTOP_SHUTDOWN; |
c9d557c1 PM |
237 | else |
238 | printk(KERN_WARNING /* but going down anyway, so... */ | |
239 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
c59ab97e | 240 | mutex_unlock(&fullstop_mutex); |
343e9099 PM |
241 | return NOTIFY_DONE; |
242 | } | |
243 | ||
c9d557c1 PM |
244 | /* |
245 | * Absorb kthreads into a kernel function that won't return, so that | |
246 | * they won't ever access module text or data again. | |
247 | */ | |
248 | static void rcutorture_shutdown_absorb(char *title) | |
249 | { | |
250 | if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { | |
251 | printk(KERN_NOTICE | |
252 | "rcutorture thread %s parking due to system shutdown\n", | |
253 | title); | |
254 | schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); | |
255 | } | |
256 | } | |
257 | ||
a241ec65 PM |
258 | /* |
259 | * Allocate an element from the rcu_tortures pool. | |
260 | */ | |
97a41e26 | 261 | static struct rcu_torture * |
a241ec65 PM |
262 | rcu_torture_alloc(void) |
263 | { | |
264 | struct list_head *p; | |
265 | ||
adac1665 | 266 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
267 | if (list_empty(&rcu_torture_freelist)) { |
268 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 269 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
270 | return NULL; |
271 | } | |
272 | atomic_inc(&n_rcu_torture_alloc); | |
273 | p = rcu_torture_freelist.next; | |
274 | list_del_init(p); | |
adac1665 | 275 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
276 | return container_of(p, struct rcu_torture, rtort_free); |
277 | } | |
278 | ||
279 | /* | |
280 | * Free an element to the rcu_tortures pool. | |
281 | */ | |
282 | static void | |
283 | rcu_torture_free(struct rcu_torture *p) | |
284 | { | |
285 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 286 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 287 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 288 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
289 | } |
290 | ||
a241ec65 PM |
291 | struct rcu_random_state { |
292 | unsigned long rrs_state; | |
75cfef32 | 293 | long rrs_count; |
a241ec65 PM |
294 | }; |
295 | ||
296 | #define RCU_RANDOM_MULT 39916801 /* prime */ | |
297 | #define RCU_RANDOM_ADD 479001701 /* prime */ | |
298 | #define RCU_RANDOM_REFRESH 10000 | |
299 | ||
300 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } | |
301 | ||
302 | /* | |
303 | * Crude but fast random-number generator. Uses a linear congruential | |
c17ac855 | 304 | * generator, with occasional help from cpu_clock(). |
a241ec65 | 305 | */ |
75cfef32 | 306 | static unsigned long |
a241ec65 PM |
307 | rcu_random(struct rcu_random_state *rrsp) |
308 | { | |
a241ec65 | 309 | if (--rrsp->rrs_count < 0) { |
c676329a | 310 | rrsp->rrs_state += (unsigned long)local_clock(); |
a241ec65 PM |
311 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
312 | } | |
313 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; | |
314 | return swahw32(rrsp->rrs_state); | |
315 | } | |
316 | ||
d120f65f | 317 | static void |
c9d557c1 | 318 | rcu_stutter_wait(char *title) |
d120f65f | 319 | { |
c9d557c1 | 320 | while (stutter_pause_test || !rcutorture_runnable) { |
e3d7be27 PM |
321 | if (rcutorture_runnable) |
322 | schedule_timeout_interruptible(1); | |
323 | else | |
3ccf79f4 | 324 | schedule_timeout_interruptible(round_jiffies_relative(HZ)); |
c9d557c1 | 325 | rcutorture_shutdown_absorb(title); |
343e9099 | 326 | } |
d120f65f PM |
327 | } |
328 | ||
72e9bb54 PM |
329 | /* |
330 | * Operations vector for selecting different types of tests. | |
331 | */ | |
332 | ||
333 | struct rcu_torture_ops { | |
334 | void (*init)(void); | |
335 | void (*cleanup)(void); | |
336 | int (*readlock)(void); | |
0acc512c | 337 | void (*read_delay)(struct rcu_random_state *rrsp); |
72e9bb54 PM |
338 | void (*readunlock)(int idx); |
339 | int (*completed)(void); | |
0acc512c | 340 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 341 | void (*sync)(void); |
fae4b54f | 342 | void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); |
2326974d | 343 | void (*cb_barrier)(void); |
bf66f18e | 344 | void (*fqs)(void); |
72e9bb54 | 345 | int (*stats)(char *page); |
0acc512c | 346 | int irq_capable; |
8e8be45e | 347 | int can_boost; |
72e9bb54 PM |
348 | char *name; |
349 | }; | |
a71fca58 PM |
350 | |
351 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
352 | |
353 | /* | |
354 | * Definitions for rcu torture testing. | |
355 | */ | |
356 | ||
a49a4af7 | 357 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
358 | { |
359 | rcu_read_lock(); | |
360 | return 0; | |
361 | } | |
362 | ||
b2896d2e PM |
363 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
364 | { | |
b8d57a76 JT |
365 | const unsigned long shortdelay_us = 200; |
366 | const unsigned long longdelay_ms = 50; | |
b2896d2e | 367 | |
b8d57a76 JT |
368 | /* We want a short delay sometimes to make a reader delay the grace |
369 | * period, and we want a long delay occasionally to trigger | |
370 | * force_quiescent_state. */ | |
b2896d2e | 371 | |
b8d57a76 JT |
372 | if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) |
373 | mdelay(longdelay_ms); | |
374 | if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) | |
375 | udelay(shortdelay_us); | |
e546f485 LJ |
376 | #ifdef CONFIG_PREEMPT |
377 | if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000))) | |
378 | preempt_schedule(); /* No QS if preempt_disable() in effect */ | |
379 | #endif | |
b2896d2e PM |
380 | } |
381 | ||
a49a4af7 | 382 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
383 | { |
384 | rcu_read_unlock(); | |
385 | } | |
386 | ||
387 | static int rcu_torture_completed(void) | |
388 | { | |
389 | return rcu_batches_completed(); | |
390 | } | |
391 | ||
392 | static void | |
393 | rcu_torture_cb(struct rcu_head *p) | |
394 | { | |
395 | int i; | |
396 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); | |
397 | ||
c9d557c1 | 398 | if (fullstop != FULLSTOP_DONTSTOP) { |
72e9bb54 PM |
399 | /* Test is ending, just drop callbacks on the floor. */ |
400 | /* The next initialization will pick up the pieces. */ | |
401 | return; | |
402 | } | |
403 | i = rp->rtort_pipe_count; | |
404 | if (i > RCU_TORTURE_PIPE_LEN) | |
405 | i = RCU_TORTURE_PIPE_LEN; | |
406 | atomic_inc(&rcu_torture_wcount[i]); | |
407 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
408 | rp->rtort_mbtest = 0; | |
409 | rcu_torture_free(rp); | |
c701d5d9 | 410 | } else { |
0acc512c | 411 | cur_ops->deferred_free(rp); |
c701d5d9 | 412 | } |
72e9bb54 PM |
413 | } |
414 | ||
d9a3da06 PM |
415 | static int rcu_no_completed(void) |
416 | { | |
417 | return 0; | |
418 | } | |
419 | ||
72e9bb54 PM |
420 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
421 | { | |
422 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
423 | } | |
424 | ||
425 | static struct rcu_torture_ops rcu_ops = { | |
0acc512c PM |
426 | .init = NULL, |
427 | .cleanup = NULL, | |
428 | .readlock = rcu_torture_read_lock, | |
429 | .read_delay = rcu_read_delay, | |
430 | .readunlock = rcu_torture_read_unlock, | |
431 | .completed = rcu_torture_completed, | |
432 | .deferred_free = rcu_torture_deferred_free, | |
433 | .sync = synchronize_rcu, | |
fae4b54f | 434 | .call = call_rcu, |
0acc512c | 435 | .cb_barrier = rcu_barrier, |
bf66f18e | 436 | .fqs = rcu_force_quiescent_state, |
0acc512c | 437 | .stats = NULL, |
a71fca58 | 438 | .irq_capable = 1, |
8e8be45e | 439 | .can_boost = rcu_can_boost(), |
a71fca58 | 440 | .name = "rcu" |
72e9bb54 PM |
441 | }; |
442 | ||
e3033736 JT |
443 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
444 | { | |
445 | int i; | |
446 | struct rcu_torture *rp; | |
447 | struct rcu_torture *rp1; | |
448 | ||
449 | cur_ops->sync(); | |
450 | list_add(&p->rtort_free, &rcu_torture_removed); | |
451 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
452 | i = rp->rtort_pipe_count; | |
453 | if (i > RCU_TORTURE_PIPE_LEN) | |
454 | i = RCU_TORTURE_PIPE_LEN; | |
455 | atomic_inc(&rcu_torture_wcount[i]); | |
456 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
457 | rp->rtort_mbtest = 0; | |
458 | list_del(&rp->rtort_free); | |
459 | rcu_torture_free(rp); | |
460 | } | |
461 | } | |
462 | } | |
463 | ||
464 | static void rcu_sync_torture_init(void) | |
465 | { | |
466 | INIT_LIST_HEAD(&rcu_torture_removed); | |
467 | } | |
468 | ||
20d2e428 | 469 | static struct rcu_torture_ops rcu_sync_ops = { |
0acc512c PM |
470 | .init = rcu_sync_torture_init, |
471 | .cleanup = NULL, | |
472 | .readlock = rcu_torture_read_lock, | |
473 | .read_delay = rcu_read_delay, | |
474 | .readunlock = rcu_torture_read_unlock, | |
475 | .completed = rcu_torture_completed, | |
476 | .deferred_free = rcu_sync_torture_deferred_free, | |
477 | .sync = synchronize_rcu, | |
fae4b54f | 478 | .call = NULL, |
0acc512c | 479 | .cb_barrier = NULL, |
bf66f18e | 480 | .fqs = rcu_force_quiescent_state, |
0acc512c PM |
481 | .stats = NULL, |
482 | .irq_capable = 1, | |
8e8be45e | 483 | .can_boost = rcu_can_boost(), |
0acc512c | 484 | .name = "rcu_sync" |
20d2e428 JT |
485 | }; |
486 | ||
d9a3da06 PM |
487 | static struct rcu_torture_ops rcu_expedited_ops = { |
488 | .init = rcu_sync_torture_init, | |
489 | .cleanup = NULL, | |
490 | .readlock = rcu_torture_read_lock, | |
491 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
492 | .readunlock = rcu_torture_read_unlock, | |
493 | .completed = rcu_no_completed, | |
494 | .deferred_free = rcu_sync_torture_deferred_free, | |
495 | .sync = synchronize_rcu_expedited, | |
fae4b54f | 496 | .call = NULL, |
d9a3da06 | 497 | .cb_barrier = NULL, |
bf66f18e | 498 | .fqs = rcu_force_quiescent_state, |
d9a3da06 PM |
499 | .stats = NULL, |
500 | .irq_capable = 1, | |
8e8be45e | 501 | .can_boost = rcu_can_boost(), |
d9a3da06 PM |
502 | .name = "rcu_expedited" |
503 | }; | |
504 | ||
c32e0660 PM |
505 | /* |
506 | * Definitions for rcu_bh torture testing. | |
507 | */ | |
508 | ||
a49a4af7 | 509 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
c32e0660 PM |
510 | { |
511 | rcu_read_lock_bh(); | |
512 | return 0; | |
513 | } | |
514 | ||
a49a4af7 | 515 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
c32e0660 PM |
516 | { |
517 | rcu_read_unlock_bh(); | |
518 | } | |
519 | ||
520 | static int rcu_bh_torture_completed(void) | |
521 | { | |
522 | return rcu_batches_completed_bh(); | |
523 | } | |
524 | ||
525 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) | |
526 | { | |
527 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); | |
528 | } | |
529 | ||
530 | static struct rcu_torture_ops rcu_bh_ops = { | |
0acc512c PM |
531 | .init = NULL, |
532 | .cleanup = NULL, | |
533 | .readlock = rcu_bh_torture_read_lock, | |
534 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
535 | .readunlock = rcu_bh_torture_read_unlock, | |
536 | .completed = rcu_bh_torture_completed, | |
537 | .deferred_free = rcu_bh_torture_deferred_free, | |
bdf2a436 | 538 | .sync = synchronize_rcu_bh, |
fae4b54f | 539 | .call = call_rcu_bh, |
0acc512c | 540 | .cb_barrier = rcu_barrier_bh, |
bf66f18e | 541 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
542 | .stats = NULL, |
543 | .irq_capable = 1, | |
544 | .name = "rcu_bh" | |
c32e0660 PM |
545 | }; |
546 | ||
11a14701 | 547 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
0acc512c PM |
548 | .init = rcu_sync_torture_init, |
549 | .cleanup = NULL, | |
550 | .readlock = rcu_bh_torture_read_lock, | |
551 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
552 | .readunlock = rcu_bh_torture_read_unlock, | |
553 | .completed = rcu_bh_torture_completed, | |
554 | .deferred_free = rcu_sync_torture_deferred_free, | |
bdf2a436 | 555 | .sync = synchronize_rcu_bh, |
fae4b54f | 556 | .call = NULL, |
0acc512c | 557 | .cb_barrier = NULL, |
bf66f18e | 558 | .fqs = rcu_bh_force_quiescent_state, |
0acc512c PM |
559 | .stats = NULL, |
560 | .irq_capable = 1, | |
561 | .name = "rcu_bh_sync" | |
11a14701 JT |
562 | }; |
563 | ||
bdf2a436 PM |
564 | static struct rcu_torture_ops rcu_bh_expedited_ops = { |
565 | .init = rcu_sync_torture_init, | |
566 | .cleanup = NULL, | |
567 | .readlock = rcu_bh_torture_read_lock, | |
568 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
569 | .readunlock = rcu_bh_torture_read_unlock, | |
570 | .completed = rcu_bh_torture_completed, | |
571 | .deferred_free = rcu_sync_torture_deferred_free, | |
572 | .sync = synchronize_rcu_bh_expedited, | |
fae4b54f | 573 | .call = NULL, |
bdf2a436 PM |
574 | .cb_barrier = NULL, |
575 | .fqs = rcu_bh_force_quiescent_state, | |
576 | .stats = NULL, | |
577 | .irq_capable = 1, | |
578 | .name = "rcu_bh_expedited" | |
579 | }; | |
580 | ||
b2896d2e PM |
581 | /* |
582 | * Definitions for srcu torture testing. | |
583 | */ | |
584 | ||
585 | static struct srcu_struct srcu_ctl; | |
b2896d2e PM |
586 | |
587 | static void srcu_torture_init(void) | |
588 | { | |
589 | init_srcu_struct(&srcu_ctl); | |
e3033736 | 590 | rcu_sync_torture_init(); |
b2896d2e PM |
591 | } |
592 | ||
593 | static void srcu_torture_cleanup(void) | |
594 | { | |
595 | synchronize_srcu(&srcu_ctl); | |
596 | cleanup_srcu_struct(&srcu_ctl); | |
597 | } | |
598 | ||
012d3ca8 | 599 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
b2896d2e PM |
600 | { |
601 | return srcu_read_lock(&srcu_ctl); | |
602 | } | |
603 | ||
604 | static void srcu_read_delay(struct rcu_random_state *rrsp) | |
605 | { | |
606 | long delay; | |
607 | const long uspertick = 1000000 / HZ; | |
608 | const long longdelay = 10; | |
609 | ||
610 | /* We want there to be long-running readers, but not all the time. */ | |
611 | ||
612 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); | |
613 | if (!delay) | |
614 | schedule_timeout_interruptible(longdelay); | |
e546f485 LJ |
615 | else |
616 | rcu_read_delay(rrsp); | |
b2896d2e PM |
617 | } |
618 | ||
012d3ca8 | 619 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
b2896d2e PM |
620 | { |
621 | srcu_read_unlock(&srcu_ctl, idx); | |
622 | } | |
623 | ||
624 | static int srcu_torture_completed(void) | |
625 | { | |
626 | return srcu_batches_completed(&srcu_ctl); | |
627 | } | |
628 | ||
9059c940 LJ |
629 | static void srcu_torture_deferred_free(struct rcu_torture *rp) |
630 | { | |
631 | call_srcu(&srcu_ctl, &rp->rtort_rcu, rcu_torture_cb); | |
632 | } | |
633 | ||
b772e1dd JT |
634 | static void srcu_torture_synchronize(void) |
635 | { | |
636 | synchronize_srcu(&srcu_ctl); | |
637 | } | |
638 | ||
e3f8d378 PM |
639 | static void srcu_torture_call(struct rcu_head *head, |
640 | void (*func)(struct rcu_head *head)) | |
641 | { | |
642 | call_srcu(&srcu_ctl, head, func); | |
643 | } | |
644 | ||
645 | static void srcu_torture_barrier(void) | |
646 | { | |
647 | srcu_barrier(&srcu_ctl); | |
648 | } | |
649 | ||
b2896d2e PM |
650 | static int srcu_torture_stats(char *page) |
651 | { | |
652 | int cnt = 0; | |
653 | int cpu; | |
654 | int idx = srcu_ctl.completed & 0x1; | |
655 | ||
656 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", | |
657 | torture_type, TORTURE_FLAG, idx); | |
658 | for_each_possible_cpu(cpu) { | |
cef50120 | 659 | cnt += sprintf(&page[cnt], " %d(%lu,%lu)", cpu, |
b2896d2e PM |
660 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], |
661 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); | |
662 | } | |
663 | cnt += sprintf(&page[cnt], "\n"); | |
664 | return cnt; | |
665 | } | |
666 | ||
667 | static struct rcu_torture_ops srcu_ops = { | |
0acc512c PM |
668 | .init = srcu_torture_init, |
669 | .cleanup = srcu_torture_cleanup, | |
670 | .readlock = srcu_torture_read_lock, | |
671 | .read_delay = srcu_read_delay, | |
672 | .readunlock = srcu_torture_read_unlock, | |
673 | .completed = srcu_torture_completed, | |
9059c940 | 674 | .deferred_free = srcu_torture_deferred_free, |
0acc512c | 675 | .sync = srcu_torture_synchronize, |
e3f8d378 PM |
676 | .call = srcu_torture_call, |
677 | .cb_barrier = srcu_torture_barrier, | |
0acc512c PM |
678 | .stats = srcu_torture_stats, |
679 | .name = "srcu" | |
b2896d2e PM |
680 | }; |
681 | ||
9059c940 LJ |
682 | static struct rcu_torture_ops srcu_sync_ops = { |
683 | .init = srcu_torture_init, | |
684 | .cleanup = srcu_torture_cleanup, | |
685 | .readlock = srcu_torture_read_lock, | |
686 | .read_delay = srcu_read_delay, | |
687 | .readunlock = srcu_torture_read_unlock, | |
688 | .completed = srcu_torture_completed, | |
689 | .deferred_free = rcu_sync_torture_deferred_free, | |
690 | .sync = srcu_torture_synchronize, | |
691 | .call = NULL, | |
692 | .cb_barrier = NULL, | |
693 | .stats = srcu_torture_stats, | |
694 | .name = "srcu_sync" | |
695 | }; | |
696 | ||
101db7b4 PM |
697 | static int srcu_torture_read_lock_raw(void) __acquires(&srcu_ctl) |
698 | { | |
699 | return srcu_read_lock_raw(&srcu_ctl); | |
700 | } | |
701 | ||
702 | static void srcu_torture_read_unlock_raw(int idx) __releases(&srcu_ctl) | |
703 | { | |
704 | srcu_read_unlock_raw(&srcu_ctl, idx); | |
705 | } | |
706 | ||
707 | static struct rcu_torture_ops srcu_raw_ops = { | |
708 | .init = srcu_torture_init, | |
709 | .cleanup = srcu_torture_cleanup, | |
710 | .readlock = srcu_torture_read_lock_raw, | |
711 | .read_delay = srcu_read_delay, | |
712 | .readunlock = srcu_torture_read_unlock_raw, | |
713 | .completed = srcu_torture_completed, | |
9059c940 | 714 | .deferred_free = srcu_torture_deferred_free, |
101db7b4 | 715 | .sync = srcu_torture_synchronize, |
fae4b54f | 716 | .call = NULL, |
101db7b4 PM |
717 | .cb_barrier = NULL, |
718 | .stats = srcu_torture_stats, | |
719 | .name = "srcu_raw" | |
720 | }; | |
721 | ||
9059c940 LJ |
722 | static struct rcu_torture_ops srcu_raw_sync_ops = { |
723 | .init = srcu_torture_init, | |
724 | .cleanup = srcu_torture_cleanup, | |
725 | .readlock = srcu_torture_read_lock_raw, | |
726 | .read_delay = srcu_read_delay, | |
727 | .readunlock = srcu_torture_read_unlock_raw, | |
728 | .completed = srcu_torture_completed, | |
729 | .deferred_free = rcu_sync_torture_deferred_free, | |
730 | .sync = srcu_torture_synchronize, | |
731 | .call = NULL, | |
732 | .cb_barrier = NULL, | |
733 | .stats = srcu_torture_stats, | |
734 | .name = "srcu_raw_sync" | |
735 | }; | |
736 | ||
804bb837 PM |
737 | static void srcu_torture_synchronize_expedited(void) |
738 | { | |
739 | synchronize_srcu_expedited(&srcu_ctl); | |
740 | } | |
741 | ||
742 | static struct rcu_torture_ops srcu_expedited_ops = { | |
743 | .init = srcu_torture_init, | |
744 | .cleanup = srcu_torture_cleanup, | |
745 | .readlock = srcu_torture_read_lock, | |
746 | .read_delay = srcu_read_delay, | |
747 | .readunlock = srcu_torture_read_unlock, | |
748 | .completed = srcu_torture_completed, | |
749 | .deferred_free = rcu_sync_torture_deferred_free, | |
750 | .sync = srcu_torture_synchronize_expedited, | |
fae4b54f | 751 | .call = NULL, |
804bb837 PM |
752 | .cb_barrier = NULL, |
753 | .stats = srcu_torture_stats, | |
754 | .name = "srcu_expedited" | |
755 | }; | |
756 | ||
4b6c2cca JT |
757 | /* |
758 | * Definitions for sched torture testing. | |
759 | */ | |
760 | ||
761 | static int sched_torture_read_lock(void) | |
762 | { | |
763 | preempt_disable(); | |
764 | return 0; | |
765 | } | |
766 | ||
767 | static void sched_torture_read_unlock(int idx) | |
768 | { | |
769 | preempt_enable(); | |
770 | } | |
771 | ||
2326974d PM |
772 | static void rcu_sched_torture_deferred_free(struct rcu_torture *p) |
773 | { | |
774 | call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); | |
775 | } | |
776 | ||
4b6c2cca | 777 | static struct rcu_torture_ops sched_ops = { |
0acc512c PM |
778 | .init = rcu_sync_torture_init, |
779 | .cleanup = NULL, | |
780 | .readlock = sched_torture_read_lock, | |
781 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
782 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 783 | .completed = rcu_no_completed, |
0acc512c | 784 | .deferred_free = rcu_sched_torture_deferred_free, |
bdf2a436 | 785 | .sync = synchronize_sched, |
0acc512c | 786 | .cb_barrier = rcu_barrier_sched, |
bf66f18e | 787 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
788 | .stats = NULL, |
789 | .irq_capable = 1, | |
790 | .name = "sched" | |
4b6c2cca JT |
791 | }; |
792 | ||
804bb837 | 793 | static struct rcu_torture_ops sched_sync_ops = { |
0acc512c PM |
794 | .init = rcu_sync_torture_init, |
795 | .cleanup = NULL, | |
796 | .readlock = sched_torture_read_lock, | |
797 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
798 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 799 | .completed = rcu_no_completed, |
0acc512c | 800 | .deferred_free = rcu_sync_torture_deferred_free, |
bdf2a436 | 801 | .sync = synchronize_sched, |
0acc512c | 802 | .cb_barrier = NULL, |
bf66f18e | 803 | .fqs = rcu_sched_force_quiescent_state, |
0acc512c PM |
804 | .stats = NULL, |
805 | .name = "sched_sync" | |
806 | }; | |
807 | ||
0acc512c PM |
808 | static struct rcu_torture_ops sched_expedited_ops = { |
809 | .init = rcu_sync_torture_init, | |
810 | .cleanup = NULL, | |
811 | .readlock = sched_torture_read_lock, | |
812 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
813 | .readunlock = sched_torture_read_unlock, | |
d9a3da06 | 814 | .completed = rcu_no_completed, |
0acc512c PM |
815 | .deferred_free = rcu_sync_torture_deferred_free, |
816 | .sync = synchronize_sched_expedited, | |
817 | .cb_barrier = NULL, | |
bf66f18e | 818 | .fqs = rcu_sched_force_quiescent_state, |
969c7921 | 819 | .stats = NULL, |
0acc512c PM |
820 | .irq_capable = 1, |
821 | .name = "sched_expedited" | |
2326974d PM |
822 | }; |
823 | ||
8e8be45e PM |
824 | /* |
825 | * RCU torture priority-boost testing. Runs one real-time thread per | |
826 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
827 | * spinning waiting for them to be invoked. If a given callback takes | |
828 | * too long to be invoked, we assume that priority inversion has occurred. | |
829 | */ | |
830 | ||
831 | struct rcu_boost_inflight { | |
832 | struct rcu_head rcu; | |
833 | int inflight; | |
834 | }; | |
835 | ||
836 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
837 | { | |
838 | struct rcu_boost_inflight *rbip = | |
839 | container_of(head, struct rcu_boost_inflight, rcu); | |
840 | ||
841 | smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ | |
842 | rbip->inflight = 0; | |
843 | } | |
844 | ||
845 | static int rcu_torture_boost(void *arg) | |
846 | { | |
847 | unsigned long call_rcu_time; | |
848 | unsigned long endtime; | |
849 | unsigned long oldstarttime; | |
850 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
851 | struct sched_param sp; | |
852 | ||
853 | VERBOSE_PRINTK_STRING("rcu_torture_boost started"); | |
854 | ||
855 | /* Set real-time priority. */ | |
856 | sp.sched_priority = 1; | |
857 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
858 | VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!"); | |
859 | n_rcu_torture_boost_rterror++; | |
860 | } | |
861 | ||
561190e3 | 862 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
863 | /* Each pass through the following loop does one boost-test cycle. */ |
864 | do { | |
865 | /* Wait for the next test interval. */ | |
866 | oldstarttime = boost_starttime; | |
93898fb1 | 867 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
8e8be45e PM |
868 | schedule_timeout_uninterruptible(1); |
869 | rcu_stutter_wait("rcu_torture_boost"); | |
870 | if (kthread_should_stop() || | |
871 | fullstop != FULLSTOP_DONTSTOP) | |
872 | goto checkwait; | |
873 | } | |
874 | ||
875 | /* Do one boost-test interval. */ | |
876 | endtime = oldstarttime + test_boost_duration * HZ; | |
877 | call_rcu_time = jiffies; | |
93898fb1 | 878 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e PM |
879 | /* If we don't have a callback in flight, post one. */ |
880 | if (!rbi.inflight) { | |
881 | smp_mb(); /* RCU core before ->inflight = 1. */ | |
882 | rbi.inflight = 1; | |
883 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); | |
884 | if (jiffies - call_rcu_time > | |
885 | test_boost_duration * HZ - HZ / 2) { | |
886 | VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed"); | |
887 | n_rcu_torture_boost_failure++; | |
888 | } | |
889 | call_rcu_time = jiffies; | |
890 | } | |
891 | cond_resched(); | |
892 | rcu_stutter_wait("rcu_torture_boost"); | |
893 | if (kthread_should_stop() || | |
894 | fullstop != FULLSTOP_DONTSTOP) | |
895 | goto checkwait; | |
896 | } | |
897 | ||
898 | /* | |
899 | * Set the start time of the next test interval. | |
900 | * Yes, this is vulnerable to long delays, but such | |
901 | * delays simply cause a false negative for the next | |
902 | * interval. Besides, we are running at RT priority, | |
903 | * so delays should be relatively rare. | |
904 | */ | |
ab8f11e5 PM |
905 | while (oldstarttime == boost_starttime && |
906 | !kthread_should_stop()) { | |
8e8be45e PM |
907 | if (mutex_trylock(&boost_mutex)) { |
908 | boost_starttime = jiffies + | |
909 | test_boost_interval * HZ; | |
910 | n_rcu_torture_boosts++; | |
911 | mutex_unlock(&boost_mutex); | |
912 | break; | |
913 | } | |
914 | schedule_timeout_uninterruptible(1); | |
915 | } | |
916 | ||
917 | /* Go do the stutter. */ | |
918 | checkwait: rcu_stutter_wait("rcu_torture_boost"); | |
919 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
920 | ||
921 | /* Clean up and exit. */ | |
922 | VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping"); | |
923 | rcutorture_shutdown_absorb("rcu_torture_boost"); | |
924 | while (!kthread_should_stop() || rbi.inflight) | |
925 | schedule_timeout_uninterruptible(1); | |
926 | smp_mb(); /* order accesses to ->inflight before stack-frame death. */ | |
9d68197c | 927 | destroy_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
928 | return 0; |
929 | } | |
930 | ||
bf66f18e PM |
931 | /* |
932 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
933 | * bursts of calls to force_quiescent_state(), increasing the probability | |
934 | * of occurrence of some important types of race conditions. | |
935 | */ | |
936 | static int | |
937 | rcu_torture_fqs(void *arg) | |
938 | { | |
939 | unsigned long fqs_resume_time; | |
940 | int fqs_burst_remaining; | |
941 | ||
942 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task started"); | |
943 | do { | |
944 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
945 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
946 | !kthread_should_stop()) { | |
bf66f18e PM |
947 | schedule_timeout_interruptible(1); |
948 | } | |
949 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
950 | while (fqs_burst_remaining > 0 && |
951 | !kthread_should_stop()) { | |
bf66f18e PM |
952 | cur_ops->fqs(); |
953 | udelay(fqs_holdoff); | |
954 | fqs_burst_remaining -= fqs_holdoff; | |
955 | } | |
956 | rcu_stutter_wait("rcu_torture_fqs"); | |
957 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
958 | VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping"); | |
959 | rcutorture_shutdown_absorb("rcu_torture_fqs"); | |
960 | while (!kthread_should_stop()) | |
961 | schedule_timeout_uninterruptible(1); | |
962 | return 0; | |
963 | } | |
964 | ||
a241ec65 PM |
965 | /* |
966 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
967 | * for that pointed to by rcu_torture_current, freeing the old structure | |
968 | * after a series of grace periods (the "pipeline"). | |
969 | */ | |
970 | static int | |
971 | rcu_torture_writer(void *arg) | |
972 | { | |
973 | int i; | |
974 | long oldbatch = rcu_batches_completed(); | |
975 | struct rcu_torture *rp; | |
976 | struct rcu_torture *old_rp; | |
977 | static DEFINE_RCU_RANDOM(rand); | |
978 | ||
979 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); | |
dbdf65b1 IM |
980 | set_user_nice(current, 19); |
981 | ||
a241ec65 PM |
982 | do { |
983 | schedule_timeout_uninterruptible(1); | |
a71fca58 PM |
984 | rp = rcu_torture_alloc(); |
985 | if (rp == NULL) | |
a241ec65 PM |
986 | continue; |
987 | rp->rtort_pipe_count = 0; | |
988 | udelay(rcu_random(&rand) & 0x3ff); | |
0ddea0ea PM |
989 | old_rp = rcu_dereference_check(rcu_torture_current, |
990 | current == writer_task); | |
996417d2 | 991 | rp->rtort_mbtest = 1; |
a241ec65 | 992 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 993 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 994 | if (old_rp) { |
a241ec65 PM |
995 | i = old_rp->rtort_pipe_count; |
996 | if (i > RCU_TORTURE_PIPE_LEN) | |
997 | i = RCU_TORTURE_PIPE_LEN; | |
998 | atomic_inc(&rcu_torture_wcount[i]); | |
999 | old_rp->rtort_pipe_count++; | |
0acc512c | 1000 | cur_ops->deferred_free(old_rp); |
a241ec65 | 1001 | } |
4a298656 | 1002 | rcutorture_record_progress(++rcu_torture_current_version); |
72e9bb54 | 1003 | oldbatch = cur_ops->completed(); |
c9d557c1 PM |
1004 | rcu_stutter_wait("rcu_torture_writer"); |
1005 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 1006 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
c9d557c1 PM |
1007 | rcutorture_shutdown_absorb("rcu_torture_writer"); |
1008 | while (!kthread_should_stop()) | |
a241ec65 PM |
1009 | schedule_timeout_uninterruptible(1); |
1010 | return 0; | |
1011 | } | |
1012 | ||
b772e1dd JT |
1013 | /* |
1014 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
1015 | * delay between calls. | |
1016 | */ | |
1017 | static int | |
1018 | rcu_torture_fakewriter(void *arg) | |
1019 | { | |
1020 | DEFINE_RCU_RANDOM(rand); | |
1021 | ||
1022 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); | |
1023 | set_user_nice(current, 19); | |
1024 | ||
1025 | do { | |
1026 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); | |
1027 | udelay(rcu_random(&rand) & 0x3ff); | |
72472a02 PM |
1028 | if (cur_ops->cb_barrier != NULL && |
1029 | rcu_random(&rand) % (nfakewriters * 8) == 0) | |
1030 | cur_ops->cb_barrier(); | |
1031 | else | |
1032 | cur_ops->sync(); | |
c9d557c1 PM |
1033 | rcu_stutter_wait("rcu_torture_fakewriter"); |
1034 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
b772e1dd JT |
1035 | |
1036 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); | |
c9d557c1 PM |
1037 | rcutorture_shutdown_absorb("rcu_torture_fakewriter"); |
1038 | while (!kthread_should_stop()) | |
b772e1dd JT |
1039 | schedule_timeout_uninterruptible(1); |
1040 | return 0; | |
1041 | } | |
1042 | ||
91afaf30 PM |
1043 | void rcutorture_trace_dump(void) |
1044 | { | |
1045 | static atomic_t beenhere = ATOMIC_INIT(0); | |
1046 | ||
1047 | if (atomic_read(&beenhere)) | |
1048 | return; | |
1049 | if (atomic_xchg(&beenhere, 1) != 0) | |
1050 | return; | |
1051 | do_trace_rcu_torture_read(cur_ops->name, (struct rcu_head *)~0UL); | |
1052 | ftrace_dump(DUMP_ALL); | |
1053 | } | |
1054 | ||
0729fbf3 PM |
1055 | /* |
1056 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
1057 | * incrementing the corresponding element of the pipeline array. The | |
1058 | * counter in the element should never be greater than 1, otherwise, the | |
1059 | * RCU implementation is broken. | |
1060 | */ | |
1061 | static void rcu_torture_timer(unsigned long unused) | |
1062 | { | |
1063 | int idx; | |
1064 | int completed; | |
1065 | static DEFINE_RCU_RANDOM(rand); | |
1066 | static DEFINE_SPINLOCK(rand_lock); | |
1067 | struct rcu_torture *p; | |
1068 | int pipe_count; | |
1069 | ||
1070 | idx = cur_ops->readlock(); | |
1071 | completed = cur_ops->completed(); | |
632ee200 | 1072 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
1073 | rcu_read_lock_bh_held() || |
1074 | rcu_read_lock_sched_held() || | |
1075 | srcu_read_lock_held(&srcu_ctl)); | |
0729fbf3 PM |
1076 | if (p == NULL) { |
1077 | /* Leave because rcu_torture_writer is not yet underway */ | |
1078 | cur_ops->readunlock(idx); | |
1079 | return; | |
1080 | } | |
7129d383 | 1081 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); |
0729fbf3 PM |
1082 | if (p->rtort_mbtest == 0) |
1083 | atomic_inc(&n_rcu_torture_mberror); | |
1084 | spin_lock(&rand_lock); | |
0acc512c | 1085 | cur_ops->read_delay(&rand); |
0729fbf3 PM |
1086 | n_rcu_torture_timers++; |
1087 | spin_unlock(&rand_lock); | |
1088 | preempt_disable(); | |
1089 | pipe_count = p->rtort_pipe_count; | |
1090 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
1091 | /* Should not happen, but... */ | |
1092 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
1093 | } | |
91afaf30 PM |
1094 | if (pipe_count > 1) |
1095 | rcutorture_trace_dump(); | |
dd17c8f7 | 1096 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
0729fbf3 PM |
1097 | completed = cur_ops->completed() - completed; |
1098 | if (completed > RCU_TORTURE_PIPE_LEN) { | |
1099 | /* Should not happen, but... */ | |
1100 | completed = RCU_TORTURE_PIPE_LEN; | |
1101 | } | |
dd17c8f7 | 1102 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 PM |
1103 | preempt_enable(); |
1104 | cur_ops->readunlock(idx); | |
1105 | } | |
1106 | ||
a241ec65 PM |
1107 | /* |
1108 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
1109 | * incrementing the corresponding element of the pipeline array. The | |
1110 | * counter in the element should never be greater than 1, otherwise, the | |
1111 | * RCU implementation is broken. | |
1112 | */ | |
1113 | static int | |
1114 | rcu_torture_reader(void *arg) | |
1115 | { | |
1116 | int completed; | |
72e9bb54 | 1117 | int idx; |
a241ec65 PM |
1118 | DEFINE_RCU_RANDOM(rand); |
1119 | struct rcu_torture *p; | |
1120 | int pipe_count; | |
0729fbf3 | 1121 | struct timer_list t; |
a241ec65 PM |
1122 | |
1123 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); | |
dbdf65b1 | 1124 | set_user_nice(current, 19); |
0acc512c | 1125 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1126 | setup_timer_on_stack(&t, rcu_torture_timer, 0); |
dbdf65b1 | 1127 | |
a241ec65 | 1128 | do { |
0acc512c | 1129 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 1130 | if (!timer_pending(&t)) |
6155fec9 | 1131 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 1132 | } |
72e9bb54 PM |
1133 | idx = cur_ops->readlock(); |
1134 | completed = cur_ops->completed(); | |
632ee200 | 1135 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
1136 | rcu_read_lock_bh_held() || |
1137 | rcu_read_lock_sched_held() || | |
1138 | srcu_read_lock_held(&srcu_ctl)); | |
a241ec65 PM |
1139 | if (p == NULL) { |
1140 | /* Wait for rcu_torture_writer to get underway */ | |
72e9bb54 | 1141 | cur_ops->readunlock(idx); |
a241ec65 PM |
1142 | schedule_timeout_interruptible(HZ); |
1143 | continue; | |
1144 | } | |
7129d383 | 1145 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); |
996417d2 PM |
1146 | if (p->rtort_mbtest == 0) |
1147 | atomic_inc(&n_rcu_torture_mberror); | |
0acc512c | 1148 | cur_ops->read_delay(&rand); |
a241ec65 PM |
1149 | preempt_disable(); |
1150 | pipe_count = p->rtort_pipe_count; | |
1151 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { | |
1152 | /* Should not happen, but... */ | |
1153 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
1154 | } | |
91afaf30 PM |
1155 | if (pipe_count > 1) |
1156 | rcutorture_trace_dump(); | |
dd17c8f7 | 1157 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
72e9bb54 | 1158 | completed = cur_ops->completed() - completed; |
a241ec65 PM |
1159 | if (completed > RCU_TORTURE_PIPE_LEN) { |
1160 | /* Should not happen, but... */ | |
1161 | completed = RCU_TORTURE_PIPE_LEN; | |
1162 | } | |
dd17c8f7 | 1163 | __this_cpu_inc(rcu_torture_batch[completed]); |
a241ec65 | 1164 | preempt_enable(); |
72e9bb54 | 1165 | cur_ops->readunlock(idx); |
a241ec65 | 1166 | schedule(); |
c9d557c1 PM |
1167 | rcu_stutter_wait("rcu_torture_reader"); |
1168 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
a241ec65 | 1169 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
c9d557c1 | 1170 | rcutorture_shutdown_absorb("rcu_torture_reader"); |
0acc512c | 1171 | if (irqreader && cur_ops->irq_capable) |
0729fbf3 | 1172 | del_timer_sync(&t); |
c9d557c1 | 1173 | while (!kthread_should_stop()) |
a241ec65 PM |
1174 | schedule_timeout_uninterruptible(1); |
1175 | return 0; | |
1176 | } | |
1177 | ||
1178 | /* | |
1179 | * Create an RCU-torture statistics message in the specified buffer. | |
1180 | */ | |
1181 | static int | |
1182 | rcu_torture_printk(char *page) | |
1183 | { | |
1184 | int cnt = 0; | |
1185 | int cpu; | |
1186 | int i; | |
1187 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1188 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1189 | ||
0a945022 | 1190 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1191 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1192 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; | |
1193 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; | |
1194 | } | |
1195 | } | |
1196 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
1197 | if (pipesummary[i] != 0) | |
1198 | break; | |
1199 | } | |
72e9bb54 | 1200 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1201 | cnt += sprintf(&page[cnt], |
5cf05ad7 | 1202 | "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", |
a241ec65 PM |
1203 | rcu_torture_current, |
1204 | rcu_torture_current_version, | |
1205 | list_empty(&rcu_torture_freelist), | |
1206 | atomic_read(&n_rcu_torture_alloc), | |
1207 | atomic_read(&n_rcu_torture_alloc_fail), | |
5cf05ad7 PM |
1208 | atomic_read(&n_rcu_torture_free)); |
1209 | cnt += sprintf(&page[cnt], "rtmbe: %d rtbke: %ld rtbre: %ld ", | |
0729fbf3 | 1210 | atomic_read(&n_rcu_torture_mberror), |
8e8be45e | 1211 | n_rcu_torture_boost_ktrerror, |
5cf05ad7 PM |
1212 | n_rcu_torture_boost_rterror); |
1213 | cnt += sprintf(&page[cnt], "rtbf: %ld rtb: %ld nt: %ld ", | |
8e8be45e PM |
1214 | n_rcu_torture_boost_failure, |
1215 | n_rcu_torture_boosts, | |
5cf05ad7 PM |
1216 | n_rcu_torture_timers); |
1217 | cnt += sprintf(&page[cnt], "onoff: %ld/%ld:%ld/%ld ", | |
b58bdcca PM |
1218 | n_online_successes, |
1219 | n_online_attempts, | |
1220 | n_offline_successes, | |
5cf05ad7 PM |
1221 | n_offline_attempts); |
1222 | cnt += sprintf(&page[cnt], "barrier: %ld/%ld:%ld", | |
fae4b54f PM |
1223 | n_barrier_successes, |
1224 | n_barrier_attempts, | |
1225 | n_rcu_torture_barrier_error); | |
1226 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); | |
8e8be45e | 1227 | if (atomic_read(&n_rcu_torture_mberror) != 0 || |
fae4b54f | 1228 | n_rcu_torture_barrier_error != 0 || |
8e8be45e PM |
1229 | n_rcu_torture_boost_ktrerror != 0 || |
1230 | n_rcu_torture_boost_rterror != 0 || | |
fae4b54f PM |
1231 | n_rcu_torture_boost_failure != 0 || |
1232 | i > 1) { | |
a241ec65 | 1233 | cnt += sprintf(&page[cnt], "!!! "); |
996417d2 | 1234 | atomic_inc(&n_rcu_torture_error); |
5af970a4 | 1235 | WARN_ON_ONCE(1); |
996417d2 | 1236 | } |
a241ec65 PM |
1237 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
1238 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) | |
1239 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); | |
72e9bb54 | 1240 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 | 1241 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
72e9bb54 | 1242 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
a241ec65 | 1243 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
72e9bb54 | 1244 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
a241ec65 PM |
1245 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
1246 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { | |
1247 | cnt += sprintf(&page[cnt], " %d", | |
1248 | atomic_read(&rcu_torture_wcount[i])); | |
1249 | } | |
1250 | cnt += sprintf(&page[cnt], "\n"); | |
c8e5b163 | 1251 | if (cur_ops->stats) |
72e9bb54 | 1252 | cnt += cur_ops->stats(&page[cnt]); |
a241ec65 PM |
1253 | return cnt; |
1254 | } | |
1255 | ||
1256 | /* | |
1257 | * Print torture statistics. Caller must ensure that there is only | |
1258 | * one call to this function at a given time!!! This is normally | |
1259 | * accomplished by relying on the module system to only have one copy | |
1260 | * of the module loaded, and then by giving the rcu_torture_stats | |
1261 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1262 | * thread is not running). | |
1263 | */ | |
1264 | static void | |
1265 | rcu_torture_stats_print(void) | |
1266 | { | |
1267 | int cnt; | |
1268 | ||
1269 | cnt = rcu_torture_printk(printk_buf); | |
1270 | printk(KERN_ALERT "%s", printk_buf); | |
1271 | } | |
1272 | ||
1273 | /* | |
1274 | * Periodically prints torture statistics, if periodic statistics printing | |
1275 | * was specified via the stat_interval module parameter. | |
1276 | * | |
1277 | * No need to worry about fullstop here, since this one doesn't reference | |
1278 | * volatile state or register callbacks. | |
1279 | */ | |
1280 | static int | |
1281 | rcu_torture_stats(void *arg) | |
1282 | { | |
1283 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); | |
1284 | do { | |
1285 | schedule_timeout_interruptible(stat_interval * HZ); | |
1286 | rcu_torture_stats_print(); | |
c9d557c1 PM |
1287 | rcutorture_shutdown_absorb("rcu_torture_stats"); |
1288 | } while (!kthread_should_stop()); | |
a241ec65 PM |
1289 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
1290 | return 0; | |
1291 | } | |
1292 | ||
d84f5203 SV |
1293 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
1294 | ||
1295 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case | |
1296 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. | |
1297 | */ | |
b2896d2e | 1298 | static void rcu_torture_shuffle_tasks(void) |
d84f5203 | 1299 | { |
d84f5203 SV |
1300 | int i; |
1301 | ||
73d0a4b1 | 1302 | cpumask_setall(shuffle_tmp_mask); |
86ef5c9a | 1303 | get_online_cpus(); |
d84f5203 SV |
1304 | |
1305 | /* No point in shuffling if there is only one online CPU (ex: UP) */ | |
c9d557c1 PM |
1306 | if (num_online_cpus() == 1) { |
1307 | put_online_cpus(); | |
1308 | return; | |
1309 | } | |
d84f5203 SV |
1310 | |
1311 | if (rcu_idle_cpu != -1) | |
73d0a4b1 | 1312 | cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); |
d84f5203 | 1313 | |
73d0a4b1 | 1314 | set_cpus_allowed_ptr(current, shuffle_tmp_mask); |
d84f5203 | 1315 | |
c8e5b163 | 1316 | if (reader_tasks) { |
d84f5203 SV |
1317 | for (i = 0; i < nrealreaders; i++) |
1318 | if (reader_tasks[i]) | |
f70316da | 1319 | set_cpus_allowed_ptr(reader_tasks[i], |
73d0a4b1 | 1320 | shuffle_tmp_mask); |
d84f5203 SV |
1321 | } |
1322 | ||
c8e5b163 | 1323 | if (fakewriter_tasks) { |
b772e1dd JT |
1324 | for (i = 0; i < nfakewriters; i++) |
1325 | if (fakewriter_tasks[i]) | |
f70316da | 1326 | set_cpus_allowed_ptr(fakewriter_tasks[i], |
73d0a4b1 | 1327 | shuffle_tmp_mask); |
b772e1dd JT |
1328 | } |
1329 | ||
d84f5203 | 1330 | if (writer_task) |
73d0a4b1 | 1331 | set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); |
d84f5203 SV |
1332 | |
1333 | if (stats_task) | |
73d0a4b1 | 1334 | set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); |
d84f5203 SV |
1335 | |
1336 | if (rcu_idle_cpu == -1) | |
1337 | rcu_idle_cpu = num_online_cpus() - 1; | |
1338 | else | |
1339 | rcu_idle_cpu--; | |
1340 | ||
86ef5c9a | 1341 | put_online_cpus(); |
d84f5203 SV |
1342 | } |
1343 | ||
1344 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the | |
1345 | * system to become idle at a time and cut off its timer ticks. This is meant | |
1346 | * to test the support for such tickless idle CPU in RCU. | |
1347 | */ | |
1348 | static int | |
1349 | rcu_torture_shuffle(void *arg) | |
1350 | { | |
1351 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); | |
1352 | do { | |
1353 | schedule_timeout_interruptible(shuffle_interval * HZ); | |
1354 | rcu_torture_shuffle_tasks(); | |
c9d557c1 PM |
1355 | rcutorture_shutdown_absorb("rcu_torture_shuffle"); |
1356 | } while (!kthread_should_stop()); | |
d84f5203 SV |
1357 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
1358 | return 0; | |
1359 | } | |
1360 | ||
d120f65f PM |
1361 | /* Cause the rcutorture test to "stutter", starting and stopping all |
1362 | * threads periodically. | |
1363 | */ | |
1364 | static int | |
1365 | rcu_torture_stutter(void *arg) | |
1366 | { | |
1367 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); | |
1368 | do { | |
1369 | schedule_timeout_interruptible(stutter * HZ); | |
1370 | stutter_pause_test = 1; | |
c9d557c1 | 1371 | if (!kthread_should_stop()) |
d120f65f PM |
1372 | schedule_timeout_interruptible(stutter * HZ); |
1373 | stutter_pause_test = 0; | |
c9d557c1 PM |
1374 | rcutorture_shutdown_absorb("rcu_torture_stutter"); |
1375 | } while (!kthread_should_stop()); | |
d120f65f PM |
1376 | VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); |
1377 | return 0; | |
1378 | } | |
1379 | ||
95c38322 | 1380 | static inline void |
8e8be45e | 1381 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag) |
95c38322 | 1382 | { |
b772e1dd JT |
1383 | printk(KERN_ALERT "%s" TORTURE_FLAG |
1384 | "--- %s: nreaders=%d nfakewriters=%d " | |
95c38322 | 1385 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
bf66f18e | 1386 | "shuffle_interval=%d stutter=%d irqreader=%d " |
8e8be45e PM |
1387 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " |
1388 | "test_boost=%d/%d test_boost_interval=%d " | |
b58bdcca | 1389 | "test_boost_duration=%d shutdown_secs=%d " |
9b9ec9b9 | 1390 | "onoff_interval=%d onoff_holdoff=%d\n", |
b772e1dd | 1391 | torture_type, tag, nrealreaders, nfakewriters, |
d120f65f | 1392 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, |
8e8be45e PM |
1393 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, |
1394 | test_boost, cur_ops->can_boost, | |
b58bdcca | 1395 | test_boost_interval, test_boost_duration, shutdown_secs, |
9b9ec9b9 | 1396 | onoff_interval, onoff_holdoff); |
95c38322 PM |
1397 | } |
1398 | ||
8e8be45e | 1399 | static struct notifier_block rcutorture_shutdown_nb = { |
343e9099 PM |
1400 | .notifier_call = rcutorture_shutdown_notify, |
1401 | }; | |
1402 | ||
8e8be45e PM |
1403 | static void rcutorture_booster_cleanup(int cpu) |
1404 | { | |
1405 | struct task_struct *t; | |
1406 | ||
1407 | if (boost_tasks[cpu] == NULL) | |
1408 | return; | |
1409 | mutex_lock(&boost_mutex); | |
1410 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task"); | |
1411 | t = boost_tasks[cpu]; | |
1412 | boost_tasks[cpu] = NULL; | |
1413 | mutex_unlock(&boost_mutex); | |
1414 | ||
1415 | /* This must be outside of the mutex, otherwise deadlock! */ | |
1416 | kthread_stop(t); | |
37e377d2 | 1417 | boost_tasks[cpu] = NULL; |
8e8be45e PM |
1418 | } |
1419 | ||
1420 | static int rcutorture_booster_init(int cpu) | |
1421 | { | |
1422 | int retval; | |
1423 | ||
1424 | if (boost_tasks[cpu] != NULL) | |
1425 | return 0; /* Already created, nothing more to do. */ | |
1426 | ||
1427 | /* Don't allow time recalculation while creating a new task. */ | |
1428 | mutex_lock(&boost_mutex); | |
1429 | VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task"); | |
1f288094 ED |
1430 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1431 | cpu_to_node(cpu), | |
1432 | "rcu_torture_boost"); | |
8e8be45e PM |
1433 | if (IS_ERR(boost_tasks[cpu])) { |
1434 | retval = PTR_ERR(boost_tasks[cpu]); | |
1435 | VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed"); | |
1436 | n_rcu_torture_boost_ktrerror++; | |
1437 | boost_tasks[cpu] = NULL; | |
1438 | mutex_unlock(&boost_mutex); | |
1439 | return retval; | |
1440 | } | |
1441 | kthread_bind(boost_tasks[cpu], cpu); | |
1442 | wake_up_process(boost_tasks[cpu]); | |
1443 | mutex_unlock(&boost_mutex); | |
1444 | return 0; | |
1445 | } | |
1446 | ||
d5f546d8 PM |
1447 | /* |
1448 | * Cause the rcutorture test to shutdown the system after the test has | |
1449 | * run for the time specified by the shutdown_secs module parameter. | |
1450 | */ | |
1451 | static int | |
1452 | rcu_torture_shutdown(void *arg) | |
1453 | { | |
1454 | long delta; | |
1455 | unsigned long jiffies_snap; | |
1456 | ||
1457 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started"); | |
1458 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1459 | while (ULONG_CMP_LT(jiffies_snap, shutdown_time) && | |
1460 | !kthread_should_stop()) { | |
1461 | delta = shutdown_time - jiffies_snap; | |
1462 | if (verbose) | |
1463 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
5cf05ad7 | 1464 | "rcu_torture_shutdown task: %lu jiffies remaining\n", |
d5f546d8 PM |
1465 | torture_type, delta); |
1466 | schedule_timeout_interruptible(delta); | |
1467 | jiffies_snap = ACCESS_ONCE(jiffies); | |
1468 | } | |
b58bdcca | 1469 | if (kthread_should_stop()) { |
d5f546d8 PM |
1470 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping"); |
1471 | return 0; | |
1472 | } | |
1473 | ||
1474 | /* OK, shut down the system. */ | |
1475 | ||
1476 | VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system"); | |
1477 | shutdown_task = NULL; /* Avoid self-kill deadlock. */ | |
1478 | rcu_torture_cleanup(); /* Get the success/failure message. */ | |
1479 | kernel_power_off(); /* Shut down the system. */ | |
1480 | return 0; | |
1481 | } | |
1482 | ||
b58bdcca PM |
1483 | #ifdef CONFIG_HOTPLUG_CPU |
1484 | ||
1485 | /* | |
1486 | * Execute random CPU-hotplug operations at the interval specified | |
1487 | * by the onoff_interval. | |
1488 | */ | |
44100306 | 1489 | static int __cpuinit |
b58bdcca PM |
1490 | rcu_torture_onoff(void *arg) |
1491 | { | |
1492 | int cpu; | |
1493 | int maxcpu = -1; | |
1494 | DEFINE_RCU_RANDOM(rand); | |
1495 | ||
1496 | VERBOSE_PRINTK_STRING("rcu_torture_onoff task started"); | |
1497 | for_each_online_cpu(cpu) | |
1498 | maxcpu = cpu; | |
1499 | WARN_ON(maxcpu < 0); | |
9b9ec9b9 PM |
1500 | if (onoff_holdoff > 0) { |
1501 | VERBOSE_PRINTK_STRING("rcu_torture_onoff begin holdoff"); | |
1502 | schedule_timeout_interruptible(onoff_holdoff * HZ); | |
1503 | VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff"); | |
1504 | } | |
b58bdcca PM |
1505 | while (!kthread_should_stop()) { |
1506 | cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1); | |
f220242a | 1507 | if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) { |
b58bdcca PM |
1508 | if (verbose) |
1509 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
1510 | "rcu_torture_onoff task: offlining %d\n", | |
1511 | torture_type, cpu); | |
1512 | n_offline_attempts++; | |
1513 | if (cpu_down(cpu) == 0) { | |
1514 | if (verbose) | |
1515 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
5cf05ad7 | 1516 | "rcu_torture_onoff task: offlined %d\n", |
b58bdcca PM |
1517 | torture_type, cpu); |
1518 | n_offline_successes++; | |
1519 | } | |
f220242a | 1520 | } else if (cpu_is_hotpluggable(cpu)) { |
b58bdcca PM |
1521 | if (verbose) |
1522 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
1523 | "rcu_torture_onoff task: onlining %d\n", | |
1524 | torture_type, cpu); | |
1525 | n_online_attempts++; | |
1526 | if (cpu_up(cpu) == 0) { | |
1527 | if (verbose) | |
1528 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
5cf05ad7 | 1529 | "rcu_torture_onoff task: onlined %d\n", |
b58bdcca PM |
1530 | torture_type, cpu); |
1531 | n_online_successes++; | |
1532 | } | |
1533 | } | |
1534 | schedule_timeout_interruptible(onoff_interval * HZ); | |
1535 | } | |
1536 | VERBOSE_PRINTK_STRING("rcu_torture_onoff task stopping"); | |
1537 | return 0; | |
1538 | } | |
1539 | ||
44100306 | 1540 | static int __cpuinit |
b58bdcca PM |
1541 | rcu_torture_onoff_init(void) |
1542 | { | |
3c1b1ce0 JL |
1543 | int ret; |
1544 | ||
b58bdcca PM |
1545 | if (onoff_interval <= 0) |
1546 | return 0; | |
1547 | onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff"); | |
1548 | if (IS_ERR(onoff_task)) { | |
3c1b1ce0 | 1549 | ret = PTR_ERR(onoff_task); |
b58bdcca | 1550 | onoff_task = NULL; |
3c1b1ce0 | 1551 | return ret; |
b58bdcca PM |
1552 | } |
1553 | return 0; | |
1554 | } | |
1555 | ||
1556 | static void rcu_torture_onoff_cleanup(void) | |
1557 | { | |
1558 | if (onoff_task == NULL) | |
1559 | return; | |
1560 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task"); | |
1561 | kthread_stop(onoff_task); | |
37e377d2 | 1562 | onoff_task = NULL; |
b58bdcca PM |
1563 | } |
1564 | ||
1565 | #else /* #ifdef CONFIG_HOTPLUG_CPU */ | |
1566 | ||
37e377d2 | 1567 | static int |
b58bdcca PM |
1568 | rcu_torture_onoff_init(void) |
1569 | { | |
37e377d2 | 1570 | return 0; |
b58bdcca PM |
1571 | } |
1572 | ||
1573 | static void rcu_torture_onoff_cleanup(void) | |
1574 | { | |
1575 | } | |
1576 | ||
1577 | #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ | |
1578 | ||
c13f3757 PM |
1579 | /* |
1580 | * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then | |
1581 | * induces a CPU stall for the time specified by stall_cpu. | |
1582 | */ | |
1583 | static int __cpuinit rcu_torture_stall(void *args) | |
1584 | { | |
1585 | unsigned long stop_at; | |
1586 | ||
1587 | VERBOSE_PRINTK_STRING("rcu_torture_stall task started"); | |
1588 | if (stall_cpu_holdoff > 0) { | |
1589 | VERBOSE_PRINTK_STRING("rcu_torture_stall begin holdoff"); | |
1590 | schedule_timeout_interruptible(stall_cpu_holdoff * HZ); | |
1591 | VERBOSE_PRINTK_STRING("rcu_torture_stall end holdoff"); | |
1592 | } | |
1593 | if (!kthread_should_stop()) { | |
1594 | stop_at = get_seconds() + stall_cpu; | |
1595 | /* RCU CPU stall is expected behavior in following code. */ | |
1596 | printk(KERN_ALERT "rcu_torture_stall start.\n"); | |
1597 | rcu_read_lock(); | |
1598 | preempt_disable(); | |
1599 | while (ULONG_CMP_LT(get_seconds(), stop_at)) | |
1600 | continue; /* Induce RCU CPU stall warning. */ | |
1601 | preempt_enable(); | |
1602 | rcu_read_unlock(); | |
1603 | printk(KERN_ALERT "rcu_torture_stall end.\n"); | |
1604 | } | |
1605 | rcutorture_shutdown_absorb("rcu_torture_stall"); | |
1606 | while (!kthread_should_stop()) | |
1607 | schedule_timeout_interruptible(10 * HZ); | |
1608 | return 0; | |
1609 | } | |
1610 | ||
1611 | /* Spawn CPU-stall kthread, if stall_cpu specified. */ | |
1612 | static int __init rcu_torture_stall_init(void) | |
1613 | { | |
1614 | int ret; | |
1615 | ||
1616 | if (stall_cpu <= 0) | |
1617 | return 0; | |
1618 | stall_task = kthread_run(rcu_torture_stall, NULL, "rcu_torture_stall"); | |
1619 | if (IS_ERR(stall_task)) { | |
1620 | ret = PTR_ERR(stall_task); | |
1621 | stall_task = NULL; | |
1622 | return ret; | |
1623 | } | |
1624 | return 0; | |
1625 | } | |
1626 | ||
1627 | /* Clean up after the CPU-stall kthread, if one was spawned. */ | |
1628 | static void rcu_torture_stall_cleanup(void) | |
1629 | { | |
1630 | if (stall_task == NULL) | |
1631 | return; | |
1632 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task."); | |
1633 | kthread_stop(stall_task); | |
37e377d2 | 1634 | stall_task = NULL; |
c13f3757 PM |
1635 | } |
1636 | ||
fae4b54f PM |
1637 | /* Callback function for RCU barrier testing. */ |
1638 | void rcu_torture_barrier_cbf(struct rcu_head *rcu) | |
1639 | { | |
1640 | atomic_inc(&barrier_cbs_invoked); | |
1641 | } | |
1642 | ||
1643 | /* kthread function to register callbacks used to test RCU barriers. */ | |
1644 | static int rcu_torture_barrier_cbs(void *arg) | |
1645 | { | |
1646 | long myid = (long)arg; | |
c6ebcbb6 | 1647 | bool lastphase = 0; |
fae4b54f PM |
1648 | struct rcu_head rcu; |
1649 | ||
1650 | init_rcu_head_on_stack(&rcu); | |
1651 | VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task started"); | |
1652 | set_user_nice(current, 19); | |
1653 | do { | |
1654 | wait_event(barrier_cbs_wq[myid], | |
c6ebcbb6 | 1655 | barrier_phase != lastphase || |
fae4b54f PM |
1656 | kthread_should_stop() || |
1657 | fullstop != FULLSTOP_DONTSTOP); | |
c6ebcbb6 PM |
1658 | lastphase = barrier_phase; |
1659 | smp_mb(); /* ensure barrier_phase load before ->call(). */ | |
fae4b54f PM |
1660 | if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) |
1661 | break; | |
1662 | cur_ops->call(&rcu, rcu_torture_barrier_cbf); | |
1663 | if (atomic_dec_and_test(&barrier_cbs_count)) | |
1664 | wake_up(&barrier_wq); | |
1665 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
1666 | VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task stopping"); | |
1667 | rcutorture_shutdown_absorb("rcu_torture_barrier_cbs"); | |
1668 | while (!kthread_should_stop()) | |
1669 | schedule_timeout_interruptible(1); | |
1670 | cur_ops->cb_barrier(); | |
1671 | destroy_rcu_head_on_stack(&rcu); | |
1672 | return 0; | |
1673 | } | |
1674 | ||
1675 | /* kthread function to drive and coordinate RCU barrier testing. */ | |
1676 | static int rcu_torture_barrier(void *arg) | |
1677 | { | |
1678 | int i; | |
1679 | ||
1680 | VERBOSE_PRINTK_STRING("rcu_torture_barrier task starting"); | |
1681 | do { | |
1682 | atomic_set(&barrier_cbs_invoked, 0); | |
1683 | atomic_set(&barrier_cbs_count, n_barrier_cbs); | |
c6ebcbb6 PM |
1684 | smp_mb(); /* Ensure barrier_phase after prior assignments. */ |
1685 | barrier_phase = !barrier_phase; | |
fae4b54f PM |
1686 | for (i = 0; i < n_barrier_cbs; i++) |
1687 | wake_up(&barrier_cbs_wq[i]); | |
1688 | wait_event(barrier_wq, | |
1689 | atomic_read(&barrier_cbs_count) == 0 || | |
1690 | kthread_should_stop() || | |
1691 | fullstop != FULLSTOP_DONTSTOP); | |
1692 | if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) | |
1693 | break; | |
1694 | n_barrier_attempts++; | |
1695 | cur_ops->cb_barrier(); | |
1696 | if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { | |
1697 | n_rcu_torture_barrier_error++; | |
1698 | WARN_ON_ONCE(1); | |
1699 | } | |
1700 | n_barrier_successes++; | |
1701 | schedule_timeout_interruptible(HZ / 10); | |
1702 | } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); | |
1703 | VERBOSE_PRINTK_STRING("rcu_torture_barrier task stopping"); | |
143aa672 | 1704 | rcutorture_shutdown_absorb("rcu_torture_barrier"); |
fae4b54f PM |
1705 | while (!kthread_should_stop()) |
1706 | schedule_timeout_interruptible(1); | |
1707 | return 0; | |
1708 | } | |
1709 | ||
1710 | /* Initialize RCU barrier testing. */ | |
1711 | static int rcu_torture_barrier_init(void) | |
1712 | { | |
1713 | int i; | |
1714 | int ret; | |
1715 | ||
1716 | if (n_barrier_cbs == 0) | |
1717 | return 0; | |
1718 | if (cur_ops->call == NULL || cur_ops->cb_barrier == NULL) { | |
1719 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
1720 | " Call or barrier ops missing for %s,\n", | |
1721 | torture_type, cur_ops->name); | |
1722 | printk(KERN_ALERT "%s" TORTURE_FLAG | |
1723 | " RCU barrier testing omitted from run.\n", | |
1724 | torture_type); | |
1725 | return 0; | |
1726 | } | |
1727 | atomic_set(&barrier_cbs_count, 0); | |
1728 | atomic_set(&barrier_cbs_invoked, 0); | |
1729 | barrier_cbs_tasks = | |
1730 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_tasks[0]), | |
1731 | GFP_KERNEL); | |
1732 | barrier_cbs_wq = | |
1733 | kzalloc(n_barrier_cbs * sizeof(barrier_cbs_wq[0]), | |
1734 | GFP_KERNEL); | |
1735 | if (barrier_cbs_tasks == NULL || barrier_cbs_wq == 0) | |
1736 | return -ENOMEM; | |
1737 | for (i = 0; i < n_barrier_cbs; i++) { | |
1738 | init_waitqueue_head(&barrier_cbs_wq[i]); | |
1739 | barrier_cbs_tasks[i] = kthread_run(rcu_torture_barrier_cbs, | |
9059c940 | 1740 | (void *)(long)i, |
fae4b54f PM |
1741 | "rcu_torture_barrier_cbs"); |
1742 | if (IS_ERR(barrier_cbs_tasks[i])) { | |
1743 | ret = PTR_ERR(barrier_cbs_tasks[i]); | |
1744 | VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier_cbs"); | |
1745 | barrier_cbs_tasks[i] = NULL; | |
1746 | return ret; | |
1747 | } | |
1748 | } | |
1749 | barrier_task = kthread_run(rcu_torture_barrier, NULL, | |
1750 | "rcu_torture_barrier"); | |
1751 | if (IS_ERR(barrier_task)) { | |
1752 | ret = PTR_ERR(barrier_task); | |
1753 | VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier"); | |
1754 | barrier_task = NULL; | |
1755 | } | |
1756 | return 0; | |
1757 | } | |
1758 | ||
1759 | /* Clean up after RCU barrier testing. */ | |
1760 | static void rcu_torture_barrier_cleanup(void) | |
1761 | { | |
1762 | int i; | |
1763 | ||
1764 | if (barrier_task != NULL) { | |
1765 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier task"); | |
1766 | kthread_stop(barrier_task); | |
1767 | barrier_task = NULL; | |
1768 | } | |
1769 | if (barrier_cbs_tasks != NULL) { | |
1770 | for (i = 0; i < n_barrier_cbs; i++) { | |
1771 | if (barrier_cbs_tasks[i] != NULL) { | |
1772 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier_cbs task"); | |
1773 | kthread_stop(barrier_cbs_tasks[i]); | |
1774 | barrier_cbs_tasks[i] = NULL; | |
1775 | } | |
1776 | } | |
1777 | kfree(barrier_cbs_tasks); | |
1778 | barrier_cbs_tasks = NULL; | |
1779 | } | |
1780 | if (barrier_cbs_wq != NULL) { | |
1781 | kfree(barrier_cbs_wq); | |
1782 | barrier_cbs_wq = NULL; | |
1783 | } | |
1784 | } | |
1785 | ||
8e8be45e PM |
1786 | static int rcutorture_cpu_notify(struct notifier_block *self, |
1787 | unsigned long action, void *hcpu) | |
1788 | { | |
1789 | long cpu = (long)hcpu; | |
1790 | ||
1791 | switch (action) { | |
1792 | case CPU_ONLINE: | |
1793 | case CPU_DOWN_FAILED: | |
1794 | (void)rcutorture_booster_init(cpu); | |
1795 | break; | |
1796 | case CPU_DOWN_PREPARE: | |
1797 | rcutorture_booster_cleanup(cpu); | |
1798 | break; | |
1799 | default: | |
1800 | break; | |
1801 | } | |
1802 | return NOTIFY_OK; | |
1803 | } | |
1804 | ||
1805 | static struct notifier_block rcutorture_cpu_nb = { | |
1806 | .notifier_call = rcutorture_cpu_notify, | |
1807 | }; | |
1808 | ||
a241ec65 PM |
1809 | static void |
1810 | rcu_torture_cleanup(void) | |
1811 | { | |
1812 | int i; | |
1813 | ||
343e9099 | 1814 | mutex_lock(&fullstop_mutex); |
4a298656 | 1815 | rcutorture_record_test_transition(); |
c9d557c1 PM |
1816 | if (fullstop == FULLSTOP_SHUTDOWN) { |
1817 | printk(KERN_WARNING /* but going down anyway, so... */ | |
1818 | "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); | |
343e9099 | 1819 | mutex_unlock(&fullstop_mutex); |
c9d557c1 | 1820 | schedule_timeout_uninterruptible(10); |
343e9099 PM |
1821 | if (cur_ops->cb_barrier != NULL) |
1822 | cur_ops->cb_barrier(); | |
1823 | return; | |
1824 | } | |
c9d557c1 | 1825 | fullstop = FULLSTOP_RMMOD; |
343e9099 | 1826 | mutex_unlock(&fullstop_mutex); |
8e8be45e | 1827 | unregister_reboot_notifier(&rcutorture_shutdown_nb); |
fae4b54f | 1828 | rcu_torture_barrier_cleanup(); |
c13f3757 | 1829 | rcu_torture_stall_cleanup(); |
d120f65f PM |
1830 | if (stutter_task) { |
1831 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); | |
1832 | kthread_stop(stutter_task); | |
1833 | } | |
1834 | stutter_task = NULL; | |
c8e5b163 | 1835 | if (shuffler_task) { |
d84f5203 SV |
1836 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
1837 | kthread_stop(shuffler_task); | |
73d0a4b1 | 1838 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
1839 | } |
1840 | shuffler_task = NULL; | |
1841 | ||
c8e5b163 | 1842 | if (writer_task) { |
a241ec65 PM |
1843 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
1844 | kthread_stop(writer_task); | |
1845 | } | |
1846 | writer_task = NULL; | |
1847 | ||
c8e5b163 | 1848 | if (reader_tasks) { |
a241ec65 | 1849 | for (i = 0; i < nrealreaders; i++) { |
c8e5b163 | 1850 | if (reader_tasks[i]) { |
a241ec65 PM |
1851 | VERBOSE_PRINTK_STRING( |
1852 | "Stopping rcu_torture_reader task"); | |
1853 | kthread_stop(reader_tasks[i]); | |
1854 | } | |
1855 | reader_tasks[i] = NULL; | |
1856 | } | |
1857 | kfree(reader_tasks); | |
1858 | reader_tasks = NULL; | |
1859 | } | |
1860 | rcu_torture_current = NULL; | |
1861 | ||
c8e5b163 | 1862 | if (fakewriter_tasks) { |
b772e1dd | 1863 | for (i = 0; i < nfakewriters; i++) { |
c8e5b163 | 1864 | if (fakewriter_tasks[i]) { |
b772e1dd JT |
1865 | VERBOSE_PRINTK_STRING( |
1866 | "Stopping rcu_torture_fakewriter task"); | |
1867 | kthread_stop(fakewriter_tasks[i]); | |
1868 | } | |
1869 | fakewriter_tasks[i] = NULL; | |
1870 | } | |
1871 | kfree(fakewriter_tasks); | |
1872 | fakewriter_tasks = NULL; | |
1873 | } | |
1874 | ||
c8e5b163 | 1875 | if (stats_task) { |
a241ec65 PM |
1876 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
1877 | kthread_stop(stats_task); | |
1878 | } | |
1879 | stats_task = NULL; | |
1880 | ||
bf66f18e PM |
1881 | if (fqs_task) { |
1882 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task"); | |
1883 | kthread_stop(fqs_task); | |
1884 | } | |
1885 | fqs_task = NULL; | |
8e8be45e PM |
1886 | if ((test_boost == 1 && cur_ops->can_boost) || |
1887 | test_boost == 2) { | |
1888 | unregister_cpu_notifier(&rcutorture_cpu_nb); | |
1889 | for_each_possible_cpu(i) | |
1890 | rcutorture_booster_cleanup(i); | |
1891 | } | |
d5f546d8 PM |
1892 | if (shutdown_task != NULL) { |
1893 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task"); | |
1894 | kthread_stop(shutdown_task); | |
1895 | } | |
37e377d2 | 1896 | shutdown_task = NULL; |
b58bdcca | 1897 | rcu_torture_onoff_cleanup(); |
bf66f18e | 1898 | |
a241ec65 | 1899 | /* Wait for all RCU callbacks to fire. */ |
2326974d PM |
1900 | |
1901 | if (cur_ops->cb_barrier != NULL) | |
1902 | cur_ops->cb_barrier(); | |
a241ec65 | 1903 | |
a241ec65 | 1904 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 1905 | |
c8e5b163 | 1906 | if (cur_ops->cleanup) |
72e9bb54 | 1907 | cur_ops->cleanup(); |
fae4b54f | 1908 | if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error) |
8e8be45e | 1909 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
091541bb PM |
1910 | else if (n_online_successes != n_online_attempts || |
1911 | n_offline_successes != n_offline_attempts) | |
1912 | rcu_torture_print_module_parms(cur_ops, | |
1913 | "End of test: RCU_HOTPLUG"); | |
95c38322 | 1914 | else |
8e8be45e | 1915 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
a241ec65 PM |
1916 | } |
1917 | ||
6f8bc500 | 1918 | static int __init |
a241ec65 PM |
1919 | rcu_torture_init(void) |
1920 | { | |
1921 | int i; | |
1922 | int cpu; | |
1923 | int firsterr = 0; | |
fae4b54f | 1924 | int retval; |
ade5fb81 | 1925 | static struct rcu_torture_ops *torture_ops[] = |
d9a3da06 | 1926 | { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, |
bdf2a436 | 1927 | &rcu_bh_ops, &rcu_bh_sync_ops, &rcu_bh_expedited_ops, |
751a68b2 PM |
1928 | &srcu_ops, &srcu_sync_ops, &srcu_expedited_ops, |
1929 | &srcu_raw_ops, &srcu_raw_sync_ops, | |
804bb837 | 1930 | &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; |
a241ec65 | 1931 | |
343e9099 PM |
1932 | mutex_lock(&fullstop_mutex); |
1933 | ||
a241ec65 | 1934 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 1935 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 1936 | cur_ops = torture_ops[i]; |
ade5fb81 | 1937 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 1938 | break; |
72e9bb54 | 1939 | } |
ade5fb81 | 1940 | if (i == ARRAY_SIZE(torture_ops)) { |
cf886c44 | 1941 | printk(KERN_ALERT "rcu-torture: invalid torture type: \"%s\"\n", |
72e9bb54 | 1942 | torture_type); |
cf886c44 PM |
1943 | printk(KERN_ALERT "rcu-torture types:"); |
1944 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) | |
1945 | printk(KERN_ALERT " %s", torture_ops[i]->name); | |
1946 | printk(KERN_ALERT "\n"); | |
343e9099 | 1947 | mutex_unlock(&fullstop_mutex); |
a71fca58 | 1948 | return -EINVAL; |
72e9bb54 | 1949 | } |
bf66f18e | 1950 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
5cf05ad7 | 1951 | printk(KERN_ALERT "rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); |
bf66f18e PM |
1952 | fqs_duration = 0; |
1953 | } | |
c8e5b163 | 1954 | if (cur_ops->init) |
72e9bb54 PM |
1955 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
1956 | ||
a241ec65 PM |
1957 | if (nreaders >= 0) |
1958 | nrealreaders = nreaders; | |
1959 | else | |
1960 | nrealreaders = 2 * num_online_cpus(); | |
8e8be45e | 1961 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
c9d557c1 | 1962 | fullstop = FULLSTOP_DONTSTOP; |
a241ec65 PM |
1963 | |
1964 | /* Set up the freelist. */ | |
1965 | ||
1966 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 1967 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 1968 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
1969 | list_add_tail(&rcu_tortures[i].rtort_free, |
1970 | &rcu_torture_freelist); | |
1971 | } | |
1972 | ||
1973 | /* Initialize the statistics so that each run gets its own numbers. */ | |
1974 | ||
1975 | rcu_torture_current = NULL; | |
1976 | rcu_torture_current_version = 0; | |
1977 | atomic_set(&n_rcu_torture_alloc, 0); | |
1978 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
1979 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
1980 | atomic_set(&n_rcu_torture_mberror, 0); |
1981 | atomic_set(&n_rcu_torture_error, 0); | |
fae4b54f | 1982 | n_rcu_torture_barrier_error = 0; |
8e8be45e PM |
1983 | n_rcu_torture_boost_ktrerror = 0; |
1984 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
1985 | n_rcu_torture_boost_failure = 0; |
1986 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
1987 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
1988 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 1989 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
1990 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
1991 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
1992 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
1993 | } | |
1994 | } | |
1995 | ||
1996 | /* Start up the kthreads. */ | |
1997 | ||
1998 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); | |
1999 | writer_task = kthread_run(rcu_torture_writer, NULL, | |
2000 | "rcu_torture_writer"); | |
2001 | if (IS_ERR(writer_task)) { | |
2002 | firsterr = PTR_ERR(writer_task); | |
2003 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); | |
2004 | writer_task = NULL; | |
2005 | goto unwind; | |
2006 | } | |
b772e1dd | 2007 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
a71fca58 | 2008 | GFP_KERNEL); |
b772e1dd JT |
2009 | if (fakewriter_tasks == NULL) { |
2010 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
2011 | firsterr = -ENOMEM; | |
2012 | goto unwind; | |
2013 | } | |
2014 | for (i = 0; i < nfakewriters; i++) { | |
2015 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); | |
2016 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, | |
a71fca58 | 2017 | "rcu_torture_fakewriter"); |
b772e1dd JT |
2018 | if (IS_ERR(fakewriter_tasks[i])) { |
2019 | firsterr = PTR_ERR(fakewriter_tasks[i]); | |
2020 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); | |
2021 | fakewriter_tasks[i] = NULL; | |
2022 | goto unwind; | |
2023 | } | |
2024 | } | |
2860aaba | 2025 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
a241ec65 PM |
2026 | GFP_KERNEL); |
2027 | if (reader_tasks == NULL) { | |
2028 | VERBOSE_PRINTK_ERRSTRING("out of memory"); | |
2029 | firsterr = -ENOMEM; | |
2030 | goto unwind; | |
2031 | } | |
2032 | for (i = 0; i < nrealreaders; i++) { | |
2033 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); | |
2034 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, | |
2035 | "rcu_torture_reader"); | |
2036 | if (IS_ERR(reader_tasks[i])) { | |
2037 | firsterr = PTR_ERR(reader_tasks[i]); | |
2038 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); | |
2039 | reader_tasks[i] = NULL; | |
2040 | goto unwind; | |
2041 | } | |
2042 | } | |
2043 | if (stat_interval > 0) { | |
2044 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); | |
2045 | stats_task = kthread_run(rcu_torture_stats, NULL, | |
2046 | "rcu_torture_stats"); | |
2047 | if (IS_ERR(stats_task)) { | |
2048 | firsterr = PTR_ERR(stats_task); | |
2049 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); | |
2050 | stats_task = NULL; | |
2051 | goto unwind; | |
2052 | } | |
2053 | } | |
d84f5203 SV |
2054 | if (test_no_idle_hz) { |
2055 | rcu_idle_cpu = num_online_cpus() - 1; | |
73d0a4b1 RR |
2056 | |
2057 | if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { | |
2058 | firsterr = -ENOMEM; | |
2059 | VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); | |
2060 | goto unwind; | |
2061 | } | |
2062 | ||
d84f5203 SV |
2063 | /* Create the shuffler thread */ |
2064 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, | |
2065 | "rcu_torture_shuffle"); | |
2066 | if (IS_ERR(shuffler_task)) { | |
73d0a4b1 | 2067 | free_cpumask_var(shuffle_tmp_mask); |
d84f5203 SV |
2068 | firsterr = PTR_ERR(shuffler_task); |
2069 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); | |
2070 | shuffler_task = NULL; | |
2071 | goto unwind; | |
2072 | } | |
2073 | } | |
d120f65f PM |
2074 | if (stutter < 0) |
2075 | stutter = 0; | |
2076 | if (stutter) { | |
2077 | /* Create the stutter thread */ | |
2078 | stutter_task = kthread_run(rcu_torture_stutter, NULL, | |
2079 | "rcu_torture_stutter"); | |
2080 | if (IS_ERR(stutter_task)) { | |
2081 | firsterr = PTR_ERR(stutter_task); | |
2082 | VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); | |
2083 | stutter_task = NULL; | |
2084 | goto unwind; | |
2085 | } | |
2086 | } | |
bf66f18e PM |
2087 | if (fqs_duration < 0) |
2088 | fqs_duration = 0; | |
2089 | if (fqs_duration) { | |
2090 | /* Create the stutter thread */ | |
2091 | fqs_task = kthread_run(rcu_torture_fqs, NULL, | |
2092 | "rcu_torture_fqs"); | |
2093 | if (IS_ERR(fqs_task)) { | |
2094 | firsterr = PTR_ERR(fqs_task); | |
2095 | VERBOSE_PRINTK_ERRSTRING("Failed to create fqs"); | |
2096 | fqs_task = NULL; | |
2097 | goto unwind; | |
2098 | } | |
2099 | } | |
8e8be45e PM |
2100 | if (test_boost_interval < 1) |
2101 | test_boost_interval = 1; | |
2102 | if (test_boost_duration < 2) | |
2103 | test_boost_duration = 2; | |
2104 | if ((test_boost == 1 && cur_ops->can_boost) || | |
2105 | test_boost == 2) { | |
8e8be45e PM |
2106 | |
2107 | boost_starttime = jiffies + test_boost_interval * HZ; | |
2108 | register_cpu_notifier(&rcutorture_cpu_nb); | |
2109 | for_each_possible_cpu(i) { | |
2110 | if (cpu_is_offline(i)) | |
2111 | continue; /* Heuristic: CPU can go offline. */ | |
2112 | retval = rcutorture_booster_init(i); | |
2113 | if (retval < 0) { | |
2114 | firsterr = retval; | |
2115 | goto unwind; | |
2116 | } | |
2117 | } | |
2118 | } | |
d5f546d8 PM |
2119 | if (shutdown_secs > 0) { |
2120 | shutdown_time = jiffies + shutdown_secs * HZ; | |
2121 | shutdown_task = kthread_run(rcu_torture_shutdown, NULL, | |
2122 | "rcu_torture_shutdown"); | |
2123 | if (IS_ERR(shutdown_task)) { | |
2124 | firsterr = PTR_ERR(shutdown_task); | |
2125 | VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown"); | |
2126 | shutdown_task = NULL; | |
2127 | goto unwind; | |
2128 | } | |
2129 | } | |
37e377d2 PM |
2130 | i = rcu_torture_onoff_init(); |
2131 | if (i != 0) { | |
2132 | firsterr = i; | |
2133 | goto unwind; | |
2134 | } | |
8e8be45e | 2135 | register_reboot_notifier(&rcutorture_shutdown_nb); |
37e377d2 PM |
2136 | i = rcu_torture_stall_init(); |
2137 | if (i != 0) { | |
2138 | firsterr = i; | |
2139 | goto unwind; | |
2140 | } | |
fae4b54f PM |
2141 | retval = rcu_torture_barrier_init(); |
2142 | if (retval != 0) { | |
2143 | firsterr = retval; | |
2144 | goto unwind; | |
2145 | } | |
4a298656 | 2146 | rcutorture_record_test_transition(); |
343e9099 | 2147 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
2148 | return 0; |
2149 | ||
2150 | unwind: | |
343e9099 | 2151 | mutex_unlock(&fullstop_mutex); |
a241ec65 PM |
2152 | rcu_torture_cleanup(); |
2153 | return firsterr; | |
2154 | } | |
2155 | ||
2156 | module_init(rcu_torture_init); | |
2157 | module_exit(rcu_torture_cleanup); |