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2e24ce88 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
a241ec65 | 2 | /* |
29766f1e | 3 | * Read-Copy Update module-based torture test facility |
a241ec65 | 4 | * |
b772e1dd | 5 | * Copyright (C) IBM Corporation, 2005, 2006 |
a241ec65 | 6 | * |
2e24ce88 | 7 | * Authors: Paul E. McKenney <paulmck@linux.ibm.com> |
e0198b29 | 8 | * Josh Triplett <josh@joshtriplett.org> |
a241ec65 PM |
9 | * |
10 | * See also: Documentation/RCU/torture.txt | |
11 | */ | |
60500037 PM |
12 | |
13 | #define pr_fmt(fmt) fmt | |
14 | ||
a241ec65 PM |
15 | #include <linux/types.h> |
16 | #include <linux/kernel.h> | |
17 | #include <linux/init.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/kthread.h> | |
20 | #include <linux/err.h> | |
21 | #include <linux/spinlock.h> | |
22 | #include <linux/smp.h> | |
23 | #include <linux/rcupdate.h> | |
24 | #include <linux/interrupt.h> | |
174cd4b1 | 25 | #include <linux/sched/signal.h> |
ae7e81c0 | 26 | #include <uapi/linux/sched/types.h> |
60063497 | 27 | #include <linux/atomic.h> |
a241ec65 | 28 | #include <linux/bitops.h> |
a241ec65 PM |
29 | #include <linux/completion.h> |
30 | #include <linux/moduleparam.h> | |
31 | #include <linux/percpu.h> | |
32 | #include <linux/notifier.h> | |
343e9099 | 33 | #include <linux/reboot.h> |
83144186 | 34 | #include <linux/freezer.h> |
a241ec65 | 35 | #include <linux/cpu.h> |
a241ec65 | 36 | #include <linux/delay.h> |
a241ec65 | 37 | #include <linux/stat.h> |
b2896d2e | 38 | #include <linux/srcu.h> |
1aeb272c | 39 | #include <linux/slab.h> |
52494535 | 40 | #include <linux/trace_clock.h> |
f07767fd | 41 | #include <asm/byteorder.h> |
51b1130e | 42 | #include <linux/torture.h> |
38706bc5 | 43 | #include <linux/vmalloc.h> |
0032f4e8 | 44 | #include <linux/sched/debug.h> |
450efca7 | 45 | #include <linux/sched/sysctl.h> |
e0aff973 | 46 | #include <linux/oom.h> |
d38e6dc6 | 47 | #include <linux/tick.h> |
a241ec65 | 48 | |
25c36329 PM |
49 | #include "rcu.h" |
50 | ||
a241ec65 | 51 | MODULE_LICENSE("GPL"); |
2e24ce88 | 52 | MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com> and Josh Triplett <josh@joshtriplett.org>"); |
a241ec65 | 53 | |
4102adab | 54 | |
2397d072 PM |
55 | /* Bits for ->extendables field, extendables param, and related definitions. */ |
56 | #define RCUTORTURE_RDR_SHIFT 8 /* Put SRCU index in upper bits. */ | |
57 | #define RCUTORTURE_RDR_MASK ((1 << RCUTORTURE_RDR_SHIFT) - 1) | |
2ceebc03 PM |
58 | #define RCUTORTURE_RDR_BH 0x01 /* Extend readers by disabling bh. */ |
59 | #define RCUTORTURE_RDR_IRQ 0x02 /* ... disabling interrupts. */ | |
60 | #define RCUTORTURE_RDR_PREEMPT 0x04 /* ... disabling preemption. */ | |
61 | #define RCUTORTURE_RDR_RBH 0x08 /* ... rcu_read_lock_bh(). */ | |
62 | #define RCUTORTURE_RDR_SCHED 0x10 /* ... rcu_read_lock_sched(). */ | |
63 | #define RCUTORTURE_RDR_RCU 0x20 /* ... entering another RCU reader. */ | |
64 | #define RCUTORTURE_RDR_NBITS 6 /* Number of bits defined above. */ | |
65 | #define RCUTORTURE_MAX_EXTEND \ | |
66 | (RCUTORTURE_RDR_BH | RCUTORTURE_RDR_IRQ | RCUTORTURE_RDR_PREEMPT | \ | |
67 | RCUTORTURE_RDR_RBH | RCUTORTURE_RDR_SCHED) | |
2397d072 PM |
68 | #define RCUTORTURE_RDR_MAX_LOOPS 0x7 /* Maximum reader extensions. */ |
69 | /* Must be power of two minus one. */ | |
c116dba6 | 70 | #define RCUTORTURE_RDR_MAX_SEGS (RCUTORTURE_RDR_MAX_LOOPS + 3) |
2397d072 | 71 | |
2397d072 PM |
72 | torture_param(int, extendables, RCUTORTURE_MAX_EXTEND, |
73 | "Extend readers by disabling bh (1), irqs (2), or preempt (4)"); | |
9e250225 PM |
74 | torture_param(int, fqs_duration, 0, |
75 | "Duration of fqs bursts (us), 0 to disable"); | |
76 | torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)"); | |
77 | torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)"); | |
1b27291b PM |
78 | torture_param(bool, fwd_progress, 1, "Test grace-period forward progress"); |
79 | torture_param(int, fwd_progress_div, 4, "Fraction of CPU stall to wait"); | |
80 | torture_param(int, fwd_progress_holdoff, 60, | |
81 | "Time between forward-progress tests (s)"); | |
82 | torture_param(bool, fwd_progress_need_resched, 1, | |
83 | "Hide cond_resched() behind need_resched()"); | |
a48f3fad | 84 | torture_param(bool, gp_cond, false, "Use conditional/async GP wait primitives"); |
9e250225 PM |
85 | torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); |
86 | torture_param(bool, gp_normal, false, | |
87 | "Use normal (non-expedited) GP wait primitives"); | |
f0bf8fab | 88 | torture_param(bool, gp_sync, false, "Use synchronous GP wait primitives"); |
9e250225 PM |
89 | torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers"); |
90 | torture_param(int, n_barrier_cbs, 0, | |
91 | "# of callbacks/kthreads for barrier testing"); | |
92 | torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads"); | |
93 | torture_param(int, nreaders, -1, "Number of RCU reader threads"); | |
94 | torture_param(int, object_debug, 0, | |
95 | "Enable debug-object double call_rcu() testing"); | |
96 | torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); | |
97 | torture_param(int, onoff_interval, 0, | |
028be12b | 98 | "Time between CPU hotplugs (jiffies), 0=disable"); |
9e250225 PM |
99 | torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); |
100 | torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); | |
101 | torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); | |
102 | torture_param(int, stall_cpu_holdoff, 10, | |
103 | "Time to wait before starting stall (s)."); | |
2b1516e5 | 104 | torture_param(int, stall_cpu_irqsoff, 0, "Disable interrupts while stalling."); |
9e250225 PM |
105 | torture_param(int, stat_interval, 60, |
106 | "Number of seconds between stats printk()s"); | |
107 | torture_param(int, stutter, 5, "Number of seconds to run/halt test"); | |
108 | torture_param(int, test_boost, 1, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); | |
109 | torture_param(int, test_boost_duration, 4, | |
110 | "Duration of each boost test, seconds."); | |
111 | torture_param(int, test_boost_interval, 7, | |
112 | "Interval between boost tests, seconds."); | |
113 | torture_param(bool, test_no_idle_hz, true, | |
114 | "Test support for tickless idle CPUs"); | |
90127d60 | 115 | torture_param(int, verbose, 1, |
b5daa8f3 | 116 | "Enable verbose debugging printk()s"); |
9e250225 | 117 | |
d10453e9 | 118 | static char *torture_type = "rcu"; |
d6ad6711 | 119 | module_param(torture_type, charp, 0444); |
c770c82a | 120 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, srcu, ...)"); |
a241ec65 | 121 | |
a241ec65 PM |
122 | static int nrealreaders; |
123 | static struct task_struct *writer_task; | |
b772e1dd | 124 | static struct task_struct **fakewriter_tasks; |
a241ec65 PM |
125 | static struct task_struct **reader_tasks; |
126 | static struct task_struct *stats_task; | |
bf66f18e | 127 | static struct task_struct *fqs_task; |
8e8be45e | 128 | static struct task_struct *boost_tasks[NR_CPUS]; |
c13f3757 | 129 | static struct task_struct *stall_task; |
1b27291b | 130 | static struct task_struct *fwd_prog_task; |
fae4b54f PM |
131 | static struct task_struct **barrier_cbs_tasks; |
132 | static struct task_struct *barrier_task; | |
a241ec65 PM |
133 | |
134 | #define RCU_TORTURE_PIPE_LEN 10 | |
135 | ||
136 | struct rcu_torture { | |
137 | struct rcu_head rtort_rcu; | |
138 | int rtort_pipe_count; | |
139 | struct list_head rtort_free; | |
996417d2 | 140 | int rtort_mbtest; |
a241ec65 PM |
141 | }; |
142 | ||
a241ec65 | 143 | static LIST_HEAD(rcu_torture_freelist); |
0ddea0ea | 144 | static struct rcu_torture __rcu *rcu_torture_current; |
4a298656 | 145 | static unsigned long rcu_torture_current_version; |
a241ec65 PM |
146 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
147 | static DEFINE_SPINLOCK(rcu_torture_lock); | |
67522bee PM |
148 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count); |
149 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch); | |
a241ec65 | 150 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; |
b2896d2e PM |
151 | static atomic_t n_rcu_torture_alloc; |
152 | static atomic_t n_rcu_torture_alloc_fail; | |
153 | static atomic_t n_rcu_torture_free; | |
154 | static atomic_t n_rcu_torture_mberror; | |
155 | static atomic_t n_rcu_torture_error; | |
fae4b54f | 156 | static long n_rcu_torture_barrier_error; |
8e8be45e PM |
157 | static long n_rcu_torture_boost_ktrerror; |
158 | static long n_rcu_torture_boost_rterror; | |
8e8be45e PM |
159 | static long n_rcu_torture_boost_failure; |
160 | static long n_rcu_torture_boosts; | |
8da9a595 | 161 | static atomic_long_t n_rcu_torture_timers; |
fae4b54f | 162 | static long n_barrier_attempts; |
bf5b6435 | 163 | static long n_barrier_successes; /* did rcu_barrier test succeed? */ |
e3033736 | 164 | static struct list_head rcu_torture_removed; |
60013d5d | 165 | static unsigned long shutdown_jiffies; |
d120f65f | 166 | |
ad0dc7f9 PM |
167 | static int rcu_torture_writer_state; |
168 | #define RTWS_FIXED_DELAY 0 | |
169 | #define RTWS_DELAY 1 | |
170 | #define RTWS_REPLACE 2 | |
171 | #define RTWS_DEF_FREE 3 | |
172 | #define RTWS_EXP_SYNC 4 | |
a48f3fad PM |
173 | #define RTWS_COND_GET 5 |
174 | #define RTWS_COND_SYNC 6 | |
f0bf8fab PM |
175 | #define RTWS_SYNC 7 |
176 | #define RTWS_STUTTER 8 | |
177 | #define RTWS_STOPPING 9 | |
18aff33e PM |
178 | static const char * const rcu_torture_writer_state_names[] = { |
179 | "RTWS_FIXED_DELAY", | |
180 | "RTWS_DELAY", | |
181 | "RTWS_REPLACE", | |
182 | "RTWS_DEF_FREE", | |
183 | "RTWS_EXP_SYNC", | |
184 | "RTWS_COND_GET", | |
185 | "RTWS_COND_SYNC", | |
186 | "RTWS_SYNC", | |
187 | "RTWS_STUTTER", | |
188 | "RTWS_STOPPING", | |
189 | }; | |
190 | ||
c116dba6 PM |
191 | /* Record reader segment types and duration for first failing read. */ |
192 | struct rt_read_seg { | |
193 | int rt_readstate; | |
194 | unsigned long rt_delay_jiffies; | |
195 | unsigned long rt_delay_ms; | |
196 | unsigned long rt_delay_us; | |
197 | bool rt_preempted; | |
198 | }; | |
199 | static int err_segs_recorded; | |
200 | static struct rt_read_seg err_segs[RCUTORTURE_RDR_MAX_SEGS]; | |
201 | static int rt_read_nsegs; | |
202 | ||
18aff33e PM |
203 | static const char *rcu_torture_writer_state_getname(void) |
204 | { | |
205 | unsigned int i = READ_ONCE(rcu_torture_writer_state); | |
206 | ||
207 | if (i >= ARRAY_SIZE(rcu_torture_writer_state_names)) | |
208 | return "???"; | |
209 | return rcu_torture_writer_state_names[i]; | |
210 | } | |
ad0dc7f9 | 211 | |
3acf4a9a | 212 | #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) |
8e8be45e | 213 | #define rcu_can_boost() 1 |
3acf4a9a | 214 | #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 215 | #define rcu_can_boost() 0 |
3acf4a9a | 216 | #endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ |
8e8be45e | 217 | |
e4aa0da3 SR |
218 | #ifdef CONFIG_RCU_TRACE |
219 | static u64 notrace rcu_trace_clock_local(void) | |
220 | { | |
221 | u64 ts = trace_clock_local(); | |
a3b7b6c2 PM |
222 | |
223 | (void)do_div(ts, NSEC_PER_USEC); | |
e4aa0da3 SR |
224 | return ts; |
225 | } | |
226 | #else /* #ifdef CONFIG_RCU_TRACE */ | |
227 | static u64 notrace rcu_trace_clock_local(void) | |
228 | { | |
229 | return 0ULL; | |
230 | } | |
231 | #endif /* #else #ifdef CONFIG_RCU_TRACE */ | |
232 | ||
60013d5d PM |
233 | /* |
234 | * Stop aggressive CPU-hog tests a bit before the end of the test in order | |
235 | * to avoid interfering with test shutdown. | |
236 | */ | |
237 | static bool shutdown_time_arrived(void) | |
238 | { | |
239 | return shutdown_secs && time_after(jiffies, shutdown_jiffies - 30 * HZ); | |
240 | } | |
241 | ||
8e8be45e | 242 | static unsigned long boost_starttime; /* jiffies of next boost test start. */ |
58ade2db | 243 | static DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ |
8e8be45e | 244 | /* and boost task create/destroy. */ |
fae4b54f | 245 | static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */ |
c6ebcbb6 | 246 | static bool barrier_phase; /* Test phase. */ |
fae4b54f PM |
247 | static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */ |
248 | static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */ | |
249 | static DECLARE_WAIT_QUEUE_HEAD(barrier_wq); | |
8e8be45e | 250 | |
48718485 PM |
251 | static bool rcu_fwd_cb_nodelay; /* Short rcu_torture_delay() delays. */ |
252 | ||
a241ec65 PM |
253 | /* |
254 | * Allocate an element from the rcu_tortures pool. | |
255 | */ | |
97a41e26 | 256 | static struct rcu_torture * |
a241ec65 PM |
257 | rcu_torture_alloc(void) |
258 | { | |
259 | struct list_head *p; | |
260 | ||
adac1665 | 261 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 PM |
262 | if (list_empty(&rcu_torture_freelist)) { |
263 | atomic_inc(&n_rcu_torture_alloc_fail); | |
adac1665 | 264 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
265 | return NULL; |
266 | } | |
267 | atomic_inc(&n_rcu_torture_alloc); | |
268 | p = rcu_torture_freelist.next; | |
269 | list_del_init(p); | |
adac1665 | 270 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
271 | return container_of(p, struct rcu_torture, rtort_free); |
272 | } | |
273 | ||
274 | /* | |
275 | * Free an element to the rcu_tortures pool. | |
276 | */ | |
277 | static void | |
278 | rcu_torture_free(struct rcu_torture *p) | |
279 | { | |
280 | atomic_inc(&n_rcu_torture_free); | |
adac1665 | 281 | spin_lock_bh(&rcu_torture_lock); |
a241ec65 | 282 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
adac1665 | 283 | spin_unlock_bh(&rcu_torture_lock); |
a241ec65 PM |
284 | } |
285 | ||
72e9bb54 PM |
286 | /* |
287 | * Operations vector for selecting different types of tests. | |
288 | */ | |
289 | ||
290 | struct rcu_torture_ops { | |
ad0dc7f9 | 291 | int ttype; |
72e9bb54 | 292 | void (*init)(void); |
ca1d51ed | 293 | void (*cleanup)(void); |
72e9bb54 | 294 | int (*readlock)(void); |
c116dba6 PM |
295 | void (*read_delay)(struct torture_random_state *rrsp, |
296 | struct rt_read_seg *rtrsp); | |
72e9bb54 | 297 | void (*readunlock)(int idx); |
17ef2fe9 | 298 | unsigned long (*get_gp_seq)(void); |
d7219312 | 299 | unsigned long (*gp_diff)(unsigned long new, unsigned long old); |
0acc512c | 300 | void (*deferred_free)(struct rcu_torture *p); |
b772e1dd | 301 | void (*sync)(void); |
2ec1f2d9 | 302 | void (*exp_sync)(void); |
a48f3fad PM |
303 | unsigned long (*get_state)(void); |
304 | void (*cond_sync)(unsigned long oldstate); | |
db3e8db4 | 305 | call_rcu_func_t call; |
2326974d | 306 | void (*cb_barrier)(void); |
bf66f18e | 307 | void (*fqs)(void); |
eea203fe | 308 | void (*stats)(void); |
1b27291b | 309 | int (*stall_dur)(void); |
0acc512c | 310 | int irq_capable; |
8e8be45e | 311 | int can_boost; |
2397d072 | 312 | int extendables; |
5eabea59 | 313 | int slow_gps; |
e66c33d5 | 314 | const char *name; |
72e9bb54 | 315 | }; |
a71fca58 PM |
316 | |
317 | static struct rcu_torture_ops *cur_ops; | |
72e9bb54 PM |
318 | |
319 | /* | |
320 | * Definitions for rcu torture testing. | |
321 | */ | |
322 | ||
a49a4af7 | 323 | static int rcu_torture_read_lock(void) __acquires(RCU) |
72e9bb54 PM |
324 | { |
325 | rcu_read_lock(); | |
326 | return 0; | |
327 | } | |
328 | ||
c116dba6 PM |
329 | static void |
330 | rcu_read_delay(struct torture_random_state *rrsp, struct rt_read_seg *rtrsp) | |
b2896d2e | 331 | { |
d0af39e8 PM |
332 | unsigned long started; |
333 | unsigned long completed; | |
b8d57a76 | 334 | const unsigned long shortdelay_us = 200; |
1e696765 | 335 | unsigned long longdelay_ms = 300; |
d0af39e8 | 336 | unsigned long long ts; |
b2896d2e | 337 | |
b8d57a76 JT |
338 | /* We want a short delay sometimes to make a reader delay the grace |
339 | * period, and we want a long delay occasionally to trigger | |
340 | * force_quiescent_state. */ | |
b2896d2e | 341 | |
102c14d2 | 342 | if (!READ_ONCE(rcu_fwd_cb_nodelay) && |
48718485 | 343 | !(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) { |
17ef2fe9 | 344 | started = cur_ops->get_gp_seq(); |
d0af39e8 | 345 | ts = rcu_trace_clock_local(); |
1e696765 PM |
346 | if (preempt_count() & (SOFTIRQ_MASK | HARDIRQ_MASK)) |
347 | longdelay_ms = 5; /* Avoid triggering BH limits. */ | |
b8d57a76 | 348 | mdelay(longdelay_ms); |
c116dba6 | 349 | rtrsp->rt_delay_ms = longdelay_ms; |
17ef2fe9 | 350 | completed = cur_ops->get_gp_seq(); |
d0af39e8 PM |
351 | do_trace_rcu_torture_read(cur_ops->name, NULL, ts, |
352 | started, completed); | |
353 | } | |
c116dba6 | 354 | if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) { |
b8d57a76 | 355 | udelay(shortdelay_us); |
c116dba6 PM |
356 | rtrsp->rt_delay_us = shortdelay_us; |
357 | } | |
51b1130e | 358 | if (!preempt_count() && |
c116dba6 | 359 | !(torture_random(rrsp) % (nrealreaders * 500))) { |
cc1321c9 | 360 | torture_preempt_schedule(); /* QS only if preemptible. */ |
c116dba6 PM |
361 | rtrsp->rt_preempted = true; |
362 | } | |
b2896d2e PM |
363 | } |
364 | ||
a49a4af7 | 365 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
72e9bb54 PM |
366 | { |
367 | rcu_read_unlock(); | |
368 | } | |
369 | ||
a48f3fad PM |
370 | /* |
371 | * Update callback in the pipe. This should be invoked after a grace period. | |
372 | */ | |
373 | static bool | |
374 | rcu_torture_pipe_update_one(struct rcu_torture *rp) | |
375 | { | |
376 | int i; | |
377 | ||
20248910 | 378 | i = READ_ONCE(rp->rtort_pipe_count); |
a48f3fad PM |
379 | if (i > RCU_TORTURE_PIPE_LEN) |
380 | i = RCU_TORTURE_PIPE_LEN; | |
381 | atomic_inc(&rcu_torture_wcount[i]); | |
20248910 PM |
382 | WRITE_ONCE(rp->rtort_pipe_count, i + 1); |
383 | if (rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { | |
a48f3fad PM |
384 | rp->rtort_mbtest = 0; |
385 | return true; | |
386 | } | |
387 | return false; | |
388 | } | |
389 | ||
390 | /* | |
391 | * Update all callbacks in the pipe. Suitable for synchronous grace-period | |
392 | * primitives. | |
393 | */ | |
394 | static void | |
395 | rcu_torture_pipe_update(struct rcu_torture *old_rp) | |
396 | { | |
397 | struct rcu_torture *rp; | |
398 | struct rcu_torture *rp1; | |
399 | ||
400 | if (old_rp) | |
401 | list_add(&old_rp->rtort_free, &rcu_torture_removed); | |
402 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { | |
403 | if (rcu_torture_pipe_update_one(rp)) { | |
404 | list_del(&rp->rtort_free); | |
405 | rcu_torture_free(rp); | |
406 | } | |
407 | } | |
408 | } | |
409 | ||
72e9bb54 PM |
410 | static void |
411 | rcu_torture_cb(struct rcu_head *p) | |
412 | { | |
72e9bb54 PM |
413 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); |
414 | ||
36970bb9 | 415 | if (torture_must_stop_irq()) { |
72e9bb54 PM |
416 | /* Test is ending, just drop callbacks on the floor. */ |
417 | /* The next initialization will pick up the pieces. */ | |
418 | return; | |
419 | } | |
a48f3fad | 420 | if (rcu_torture_pipe_update_one(rp)) |
72e9bb54 | 421 | rcu_torture_free(rp); |
a48f3fad | 422 | else |
0acc512c | 423 | cur_ops->deferred_free(rp); |
72e9bb54 PM |
424 | } |
425 | ||
6b80da42 | 426 | static unsigned long rcu_no_completed(void) |
d9a3da06 PM |
427 | { |
428 | return 0; | |
429 | } | |
430 | ||
72e9bb54 PM |
431 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
432 | { | |
433 | call_rcu(&p->rtort_rcu, rcu_torture_cb); | |
434 | } | |
435 | ||
e3033736 JT |
436 | static void rcu_sync_torture_init(void) |
437 | { | |
438 | INIT_LIST_HEAD(&rcu_torture_removed); | |
439 | } | |
440 | ||
2ec1f2d9 | 441 | static struct rcu_torture_ops rcu_ops = { |
ad0dc7f9 | 442 | .ttype = RCU_FLAVOR, |
0acc512c | 443 | .init = rcu_sync_torture_init, |
0acc512c PM |
444 | .readlock = rcu_torture_read_lock, |
445 | .read_delay = rcu_read_delay, | |
446 | .readunlock = rcu_torture_read_unlock, | |
17ef2fe9 | 447 | .get_gp_seq = rcu_get_gp_seq, |
d7219312 | 448 | .gp_diff = rcu_seq_diff, |
2ec1f2d9 | 449 | .deferred_free = rcu_torture_deferred_free, |
0acc512c | 450 | .sync = synchronize_rcu, |
2ec1f2d9 | 451 | .exp_sync = synchronize_rcu_expedited, |
a48f3fad PM |
452 | .get_state = get_state_synchronize_rcu, |
453 | .cond_sync = cond_synchronize_rcu, | |
2ec1f2d9 PM |
454 | .call = call_rcu, |
455 | .cb_barrier = rcu_barrier, | |
bf66f18e | 456 | .fqs = rcu_force_quiescent_state, |
d9a3da06 | 457 | .stats = NULL, |
1b27291b | 458 | .stall_dur = rcu_jiffies_till_stall_check, |
d9a3da06 | 459 | .irq_capable = 1, |
8e8be45e | 460 | .can_boost = rcu_can_boost(), |
c0335743 | 461 | .extendables = RCUTORTURE_MAX_EXTEND, |
2ec1f2d9 | 462 | .name = "rcu" |
d9a3da06 PM |
463 | }; |
464 | ||
ff20e251 PM |
465 | /* |
466 | * Don't even think about trying any of these in real life!!! | |
467 | * The names includes "busted", and they really means it! | |
468 | * The only purpose of these functions is to provide a buggy RCU | |
469 | * implementation to make sure that rcutorture correctly emits | |
470 | * buggy-RCU error messages. | |
471 | */ | |
472 | static void rcu_busted_torture_deferred_free(struct rcu_torture *p) | |
473 | { | |
474 | /* This is a deliberate bug for testing purposes only! */ | |
475 | rcu_torture_cb(&p->rtort_rcu); | |
476 | } | |
477 | ||
478 | static void synchronize_rcu_busted(void) | |
479 | { | |
480 | /* This is a deliberate bug for testing purposes only! */ | |
481 | } | |
482 | ||
483 | static void | |
b6a4ae76 | 484 | call_rcu_busted(struct rcu_head *head, rcu_callback_t func) |
ff20e251 PM |
485 | { |
486 | /* This is a deliberate bug for testing purposes only! */ | |
487 | func(head); | |
488 | } | |
489 | ||
490 | static struct rcu_torture_ops rcu_busted_ops = { | |
ad0dc7f9 | 491 | .ttype = INVALID_RCU_FLAVOR, |
ff20e251 PM |
492 | .init = rcu_sync_torture_init, |
493 | .readlock = rcu_torture_read_lock, | |
494 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
495 | .readunlock = rcu_torture_read_unlock, | |
17ef2fe9 | 496 | .get_gp_seq = rcu_no_completed, |
ff20e251 PM |
497 | .deferred_free = rcu_busted_torture_deferred_free, |
498 | .sync = synchronize_rcu_busted, | |
499 | .exp_sync = synchronize_rcu_busted, | |
500 | .call = call_rcu_busted, | |
501 | .cb_barrier = NULL, | |
502 | .fqs = NULL, | |
503 | .stats = NULL, | |
504 | .irq_capable = 1, | |
b3c98314 | 505 | .name = "busted" |
ff20e251 PM |
506 | }; |
507 | ||
b2896d2e PM |
508 | /* |
509 | * Definitions for srcu torture testing. | |
510 | */ | |
511 | ||
cda4dc81 | 512 | DEFINE_STATIC_SRCU(srcu_ctl); |
ca1d51ed PM |
513 | static struct srcu_struct srcu_ctld; |
514 | static struct srcu_struct *srcu_ctlp = &srcu_ctl; | |
b2896d2e | 515 | |
ca1d51ed | 516 | static int srcu_torture_read_lock(void) __acquires(srcu_ctlp) |
b2896d2e | 517 | { |
ca1d51ed | 518 | return srcu_read_lock(srcu_ctlp); |
b2896d2e PM |
519 | } |
520 | ||
c116dba6 PM |
521 | static void |
522 | srcu_read_delay(struct torture_random_state *rrsp, struct rt_read_seg *rtrsp) | |
b2896d2e PM |
523 | { |
524 | long delay; | |
525 | const long uspertick = 1000000 / HZ; | |
526 | const long longdelay = 10; | |
527 | ||
528 | /* We want there to be long-running readers, but not all the time. */ | |
529 | ||
51b1130e PM |
530 | delay = torture_random(rrsp) % |
531 | (nrealreaders * 2 * longdelay * uspertick); | |
c116dba6 | 532 | if (!delay && in_task()) { |
b2896d2e | 533 | schedule_timeout_interruptible(longdelay); |
c116dba6 PM |
534 | rtrsp->rt_delay_jiffies = longdelay; |
535 | } else { | |
536 | rcu_read_delay(rrsp, rtrsp); | |
537 | } | |
b2896d2e PM |
538 | } |
539 | ||
ca1d51ed | 540 | static void srcu_torture_read_unlock(int idx) __releases(srcu_ctlp) |
b2896d2e | 541 | { |
ca1d51ed | 542 | srcu_read_unlock(srcu_ctlp, idx); |
b2896d2e PM |
543 | } |
544 | ||
6b80da42 | 545 | static unsigned long srcu_torture_completed(void) |
b2896d2e | 546 | { |
ca1d51ed | 547 | return srcu_batches_completed(srcu_ctlp); |
b2896d2e PM |
548 | } |
549 | ||
9059c940 LJ |
550 | static void srcu_torture_deferred_free(struct rcu_torture *rp) |
551 | { | |
ca1d51ed | 552 | call_srcu(srcu_ctlp, &rp->rtort_rcu, rcu_torture_cb); |
9059c940 LJ |
553 | } |
554 | ||
b772e1dd JT |
555 | static void srcu_torture_synchronize(void) |
556 | { | |
ca1d51ed | 557 | synchronize_srcu(srcu_ctlp); |
b772e1dd JT |
558 | } |
559 | ||
e3f8d378 | 560 | static void srcu_torture_call(struct rcu_head *head, |
b6a4ae76 | 561 | rcu_callback_t func) |
e3f8d378 | 562 | { |
ca1d51ed | 563 | call_srcu(srcu_ctlp, head, func); |
e3f8d378 PM |
564 | } |
565 | ||
566 | static void srcu_torture_barrier(void) | |
567 | { | |
ca1d51ed | 568 | srcu_barrier(srcu_ctlp); |
e3f8d378 PM |
569 | } |
570 | ||
eea203fe | 571 | static void srcu_torture_stats(void) |
b2896d2e | 572 | { |
115a1a52 | 573 | srcu_torture_stats_print(srcu_ctlp, torture_type, TORTURE_FLAG); |
b2896d2e PM |
574 | } |
575 | ||
2ec1f2d9 PM |
576 | static void srcu_torture_synchronize_expedited(void) |
577 | { | |
ca1d51ed | 578 | synchronize_srcu_expedited(srcu_ctlp); |
2ec1f2d9 PM |
579 | } |
580 | ||
b2896d2e | 581 | static struct rcu_torture_ops srcu_ops = { |
ad0dc7f9 | 582 | .ttype = SRCU_FLAVOR, |
cda4dc81 | 583 | .init = rcu_sync_torture_init, |
0acc512c PM |
584 | .readlock = srcu_torture_read_lock, |
585 | .read_delay = srcu_read_delay, | |
586 | .readunlock = srcu_torture_read_unlock, | |
17ef2fe9 | 587 | .get_gp_seq = srcu_torture_completed, |
9059c940 | 588 | .deferred_free = srcu_torture_deferred_free, |
0acc512c | 589 | .sync = srcu_torture_synchronize, |
2ec1f2d9 | 590 | .exp_sync = srcu_torture_synchronize_expedited, |
e3f8d378 PM |
591 | .call = srcu_torture_call, |
592 | .cb_barrier = srcu_torture_barrier, | |
0acc512c | 593 | .stats = srcu_torture_stats, |
5e741fa9 | 594 | .irq_capable = 1, |
0acc512c | 595 | .name = "srcu" |
b2896d2e PM |
596 | }; |
597 | ||
ca1d51ed PM |
598 | static void srcu_torture_init(void) |
599 | { | |
600 | rcu_sync_torture_init(); | |
601 | WARN_ON(init_srcu_struct(&srcu_ctld)); | |
602 | srcu_ctlp = &srcu_ctld; | |
603 | } | |
604 | ||
605 | static void srcu_torture_cleanup(void) | |
606 | { | |
f5ad3991 | 607 | cleanup_srcu_struct(&srcu_ctld); |
ca1d51ed PM |
608 | srcu_ctlp = &srcu_ctl; /* In case of a later rcutorture run. */ |
609 | } | |
610 | ||
611 | /* As above, but dynamically allocated. */ | |
612 | static struct rcu_torture_ops srcud_ops = { | |
613 | .ttype = SRCU_FLAVOR, | |
614 | .init = srcu_torture_init, | |
615 | .cleanup = srcu_torture_cleanup, | |
616 | .readlock = srcu_torture_read_lock, | |
617 | .read_delay = srcu_read_delay, | |
618 | .readunlock = srcu_torture_read_unlock, | |
17ef2fe9 | 619 | .get_gp_seq = srcu_torture_completed, |
ca1d51ed PM |
620 | .deferred_free = srcu_torture_deferred_free, |
621 | .sync = srcu_torture_synchronize, | |
622 | .exp_sync = srcu_torture_synchronize_expedited, | |
623 | .call = srcu_torture_call, | |
624 | .cb_barrier = srcu_torture_barrier, | |
625 | .stats = srcu_torture_stats, | |
5e741fa9 | 626 | .irq_capable = 1, |
ca1d51ed PM |
627 | .name = "srcud" |
628 | }; | |
629 | ||
2397d072 PM |
630 | /* As above, but broken due to inappropriate reader extension. */ |
631 | static struct rcu_torture_ops busted_srcud_ops = { | |
632 | .ttype = SRCU_FLAVOR, | |
633 | .init = srcu_torture_init, | |
634 | .cleanup = srcu_torture_cleanup, | |
635 | .readlock = srcu_torture_read_lock, | |
636 | .read_delay = rcu_read_delay, | |
637 | .readunlock = srcu_torture_read_unlock, | |
638 | .get_gp_seq = srcu_torture_completed, | |
639 | .deferred_free = srcu_torture_deferred_free, | |
640 | .sync = srcu_torture_synchronize, | |
641 | .exp_sync = srcu_torture_synchronize_expedited, | |
642 | .call = srcu_torture_call, | |
643 | .cb_barrier = srcu_torture_barrier, | |
644 | .stats = srcu_torture_stats, | |
645 | .irq_capable = 1, | |
646 | .extendables = RCUTORTURE_MAX_EXTEND, | |
647 | .name = "busted_srcud" | |
648 | }; | |
649 | ||
69c60455 PM |
650 | /* |
651 | * Definitions for RCU-tasks torture testing. | |
652 | */ | |
653 | ||
654 | static int tasks_torture_read_lock(void) | |
655 | { | |
656 | return 0; | |
657 | } | |
658 | ||
659 | static void tasks_torture_read_unlock(int idx) | |
660 | { | |
661 | } | |
662 | ||
663 | static void rcu_tasks_torture_deferred_free(struct rcu_torture *p) | |
664 | { | |
665 | call_rcu_tasks(&p->rtort_rcu, rcu_torture_cb); | |
666 | } | |
667 | ||
668 | static struct rcu_torture_ops tasks_ops = { | |
669 | .ttype = RCU_TASKS_FLAVOR, | |
670 | .init = rcu_sync_torture_init, | |
671 | .readlock = tasks_torture_read_lock, | |
672 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
673 | .readunlock = tasks_torture_read_unlock, | |
17ef2fe9 | 674 | .get_gp_seq = rcu_no_completed, |
69c60455 PM |
675 | .deferred_free = rcu_tasks_torture_deferred_free, |
676 | .sync = synchronize_rcu_tasks, | |
677 | .exp_sync = synchronize_rcu_tasks, | |
678 | .call = call_rcu_tasks, | |
679 | .cb_barrier = rcu_barrier_tasks, | |
680 | .fqs = NULL, | |
681 | .stats = NULL, | |
682 | .irq_capable = 1, | |
5eabea59 | 683 | .slow_gps = 1, |
69c60455 PM |
684 | .name = "tasks" |
685 | }; | |
686 | ||
c682db55 PM |
687 | /* |
688 | * Definitions for trivial CONFIG_PREEMPT=n-only torture testing. | |
689 | * This implementation does not necessarily work well with CPU hotplug. | |
690 | */ | |
691 | ||
692 | static void synchronize_rcu_trivial(void) | |
693 | { | |
694 | int cpu; | |
695 | ||
696 | for_each_online_cpu(cpu) { | |
697 | rcutorture_sched_setaffinity(current->pid, cpumask_of(cpu)); | |
698 | WARN_ON_ONCE(raw_smp_processor_id() != cpu); | |
699 | } | |
700 | } | |
701 | ||
702 | static int rcu_torture_read_lock_trivial(void) __acquires(RCU) | |
703 | { | |
704 | preempt_disable(); | |
705 | return 0; | |
706 | } | |
707 | ||
708 | static void rcu_torture_read_unlock_trivial(int idx) __releases(RCU) | |
709 | { | |
710 | preempt_enable(); | |
711 | } | |
712 | ||
713 | static struct rcu_torture_ops trivial_ops = { | |
714 | .ttype = RCU_TRIVIAL_FLAVOR, | |
715 | .init = rcu_sync_torture_init, | |
716 | .readlock = rcu_torture_read_lock_trivial, | |
717 | .read_delay = rcu_read_delay, /* just reuse rcu's version. */ | |
718 | .readunlock = rcu_torture_read_unlock_trivial, | |
719 | .get_gp_seq = rcu_no_completed, | |
720 | .sync = synchronize_rcu_trivial, | |
721 | .exp_sync = synchronize_rcu_trivial, | |
722 | .fqs = NULL, | |
723 | .stats = NULL, | |
724 | .irq_capable = 1, | |
725 | .name = "trivial" | |
726 | }; | |
727 | ||
d7219312 PM |
728 | static unsigned long rcutorture_seq_diff(unsigned long new, unsigned long old) |
729 | { | |
730 | if (!cur_ops->gp_diff) | |
731 | return new - old; | |
732 | return cur_ops->gp_diff(new, old); | |
733 | } | |
734 | ||
5be5d1a1 PM |
735 | static bool __maybe_unused torturing_tasks(void) |
736 | { | |
737 | return cur_ops == &tasks_ops; | |
738 | } | |
739 | ||
8e8be45e PM |
740 | /* |
741 | * RCU torture priority-boost testing. Runs one real-time thread per | |
742 | * CPU for moderate bursts, repeatedly registering RCU callbacks and | |
743 | * spinning waiting for them to be invoked. If a given callback takes | |
744 | * too long to be invoked, we assume that priority inversion has occurred. | |
745 | */ | |
746 | ||
747 | struct rcu_boost_inflight { | |
748 | struct rcu_head rcu; | |
749 | int inflight; | |
750 | }; | |
751 | ||
752 | static void rcu_torture_boost_cb(struct rcu_head *head) | |
753 | { | |
754 | struct rcu_boost_inflight *rbip = | |
755 | container_of(head, struct rcu_boost_inflight, rcu); | |
756 | ||
6c7ed42c PM |
757 | /* Ensure RCU-core accesses precede clearing ->inflight */ |
758 | smp_store_release(&rbip->inflight, 0); | |
8e8be45e PM |
759 | } |
760 | ||
450efca7 JFG |
761 | static int old_rt_runtime = -1; |
762 | ||
763 | static void rcu_torture_disable_rt_throttle(void) | |
764 | { | |
765 | /* | |
766 | * Disable RT throttling so that rcutorture's boost threads don't get | |
767 | * throttled. Only possible if rcutorture is built-in otherwise the | |
768 | * user should manually do this by setting the sched_rt_period_us and | |
769 | * sched_rt_runtime sysctls. | |
770 | */ | |
771 | if (!IS_BUILTIN(CONFIG_RCU_TORTURE_TEST) || old_rt_runtime != -1) | |
772 | return; | |
773 | ||
774 | old_rt_runtime = sysctl_sched_rt_runtime; | |
775 | sysctl_sched_rt_runtime = -1; | |
776 | } | |
777 | ||
778 | static void rcu_torture_enable_rt_throttle(void) | |
779 | { | |
780 | if (!IS_BUILTIN(CONFIG_RCU_TORTURE_TEST) || old_rt_runtime == -1) | |
781 | return; | |
782 | ||
783 | sysctl_sched_rt_runtime = old_rt_runtime; | |
784 | old_rt_runtime = -1; | |
785 | } | |
786 | ||
3b745c89 JFG |
787 | static bool rcu_torture_boost_failed(unsigned long start, unsigned long end) |
788 | { | |
789 | if (end - start > test_boost_duration * HZ - HZ / 2) { | |
790 | VERBOSE_TOROUT_STRING("rcu_torture_boost boosting failed"); | |
791 | n_rcu_torture_boost_failure++; | |
792 | ||
793 | return true; /* failed */ | |
794 | } | |
795 | ||
796 | return false; /* passed */ | |
797 | } | |
798 | ||
8e8be45e PM |
799 | static int rcu_torture_boost(void *arg) |
800 | { | |
801 | unsigned long call_rcu_time; | |
802 | unsigned long endtime; | |
803 | unsigned long oldstarttime; | |
804 | struct rcu_boost_inflight rbi = { .inflight = 0 }; | |
805 | struct sched_param sp; | |
806 | ||
5ccf60f2 | 807 | VERBOSE_TOROUT_STRING("rcu_torture_boost started"); |
8e8be45e PM |
808 | |
809 | /* Set real-time priority. */ | |
810 | sp.sched_priority = 1; | |
811 | if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { | |
5ccf60f2 | 812 | VERBOSE_TOROUT_STRING("rcu_torture_boost RT prio failed!"); |
8e8be45e PM |
813 | n_rcu_torture_boost_rterror++; |
814 | } | |
815 | ||
561190e3 | 816 | init_rcu_head_on_stack(&rbi.rcu); |
8e8be45e PM |
817 | /* Each pass through the following loop does one boost-test cycle. */ |
818 | do { | |
3b745c89 JFG |
819 | /* Track if the test failed already in this test interval? */ |
820 | bool failed = false; | |
821 | ||
822 | /* Increment n_rcu_torture_boosts once per boost-test */ | |
823 | while (!kthread_should_stop()) { | |
824 | if (mutex_trylock(&boost_mutex)) { | |
825 | n_rcu_torture_boosts++; | |
826 | mutex_unlock(&boost_mutex); | |
827 | break; | |
828 | } | |
829 | schedule_timeout_uninterruptible(1); | |
830 | } | |
831 | if (kthread_should_stop()) | |
832 | goto checkwait; | |
833 | ||
8e8be45e PM |
834 | /* Wait for the next test interval. */ |
835 | oldstarttime = boost_starttime; | |
93898fb1 | 836 | while (ULONG_CMP_LT(jiffies, oldstarttime)) { |
0e11c8e8 | 837 | schedule_timeout_interruptible(oldstarttime - jiffies); |
628edaa5 | 838 | stutter_wait("rcu_torture_boost"); |
36970bb9 | 839 | if (torture_must_stop()) |
8e8be45e PM |
840 | goto checkwait; |
841 | } | |
842 | ||
843 | /* Do one boost-test interval. */ | |
844 | endtime = oldstarttime + test_boost_duration * HZ; | |
845 | call_rcu_time = jiffies; | |
93898fb1 | 846 | while (ULONG_CMP_LT(jiffies, endtime)) { |
8e8be45e | 847 | /* If we don't have a callback in flight, post one. */ |
6c7ed42c PM |
848 | if (!smp_load_acquire(&rbi.inflight)) { |
849 | /* RCU core before ->inflight = 1. */ | |
850 | smp_store_release(&rbi.inflight, 1); | |
8e8be45e | 851 | call_rcu(&rbi.rcu, rcu_torture_boost_cb); |
3b745c89 JFG |
852 | /* Check if the boost test failed */ |
853 | failed = failed || | |
854 | rcu_torture_boost_failed(call_rcu_time, | |
855 | jiffies); | |
8e8be45e PM |
856 | call_rcu_time = jiffies; |
857 | } | |
628edaa5 | 858 | stutter_wait("rcu_torture_boost"); |
36970bb9 | 859 | if (torture_must_stop()) |
8e8be45e PM |
860 | goto checkwait; |
861 | } | |
862 | ||
3b745c89 JFG |
863 | /* |
864 | * If boost never happened, then inflight will always be 1, in | |
865 | * this case the boost check would never happen in the above | |
866 | * loop so do another one here. | |
867 | */ | |
868 | if (!failed && smp_load_acquire(&rbi.inflight)) | |
869 | rcu_torture_boost_failed(call_rcu_time, jiffies); | |
870 | ||
8e8be45e PM |
871 | /* |
872 | * Set the start time of the next test interval. | |
873 | * Yes, this is vulnerable to long delays, but such | |
874 | * delays simply cause a false negative for the next | |
875 | * interval. Besides, we are running at RT priority, | |
876 | * so delays should be relatively rare. | |
877 | */ | |
ab8f11e5 PM |
878 | while (oldstarttime == boost_starttime && |
879 | !kthread_should_stop()) { | |
8e8be45e PM |
880 | if (mutex_trylock(&boost_mutex)) { |
881 | boost_starttime = jiffies + | |
882 | test_boost_interval * HZ; | |
8e8be45e PM |
883 | mutex_unlock(&boost_mutex); |
884 | break; | |
885 | } | |
886 | schedule_timeout_uninterruptible(1); | |
887 | } | |
888 | ||
889 | /* Go do the stutter. */ | |
628edaa5 | 890 | checkwait: stutter_wait("rcu_torture_boost"); |
36970bb9 | 891 | } while (!torture_must_stop()); |
8e8be45e PM |
892 | |
893 | /* Clean up and exit. */ | |
6c7ed42c | 894 | while (!kthread_should_stop() || smp_load_acquire(&rbi.inflight)) { |
7fafaac5 | 895 | torture_shutdown_absorb("rcu_torture_boost"); |
8e8be45e | 896 | schedule_timeout_uninterruptible(1); |
7fafaac5 | 897 | } |
9d68197c | 898 | destroy_rcu_head_on_stack(&rbi.rcu); |
7fafaac5 | 899 | torture_kthread_stopping("rcu_torture_boost"); |
8e8be45e PM |
900 | return 0; |
901 | } | |
902 | ||
bf66f18e PM |
903 | /* |
904 | * RCU torture force-quiescent-state kthread. Repeatedly induces | |
905 | * bursts of calls to force_quiescent_state(), increasing the probability | |
906 | * of occurrence of some important types of race conditions. | |
907 | */ | |
908 | static int | |
909 | rcu_torture_fqs(void *arg) | |
910 | { | |
911 | unsigned long fqs_resume_time; | |
912 | int fqs_burst_remaining; | |
913 | ||
5ccf60f2 | 914 | VERBOSE_TOROUT_STRING("rcu_torture_fqs task started"); |
bf66f18e PM |
915 | do { |
916 | fqs_resume_time = jiffies + fqs_stutter * HZ; | |
93898fb1 PM |
917 | while (ULONG_CMP_LT(jiffies, fqs_resume_time) && |
918 | !kthread_should_stop()) { | |
bf66f18e PM |
919 | schedule_timeout_interruptible(1); |
920 | } | |
921 | fqs_burst_remaining = fqs_duration; | |
93898fb1 PM |
922 | while (fqs_burst_remaining > 0 && |
923 | !kthread_should_stop()) { | |
bf66f18e PM |
924 | cur_ops->fqs(); |
925 | udelay(fqs_holdoff); | |
926 | fqs_burst_remaining -= fqs_holdoff; | |
927 | } | |
628edaa5 | 928 | stutter_wait("rcu_torture_fqs"); |
36970bb9 | 929 | } while (!torture_must_stop()); |
7fafaac5 | 930 | torture_kthread_stopping("rcu_torture_fqs"); |
bf66f18e PM |
931 | return 0; |
932 | } | |
933 | ||
a241ec65 PM |
934 | /* |
935 | * RCU torture writer kthread. Repeatedly substitutes a new structure | |
936 | * for that pointed to by rcu_torture_current, freeing the old structure | |
937 | * after a series of grace periods (the "pipeline"). | |
938 | */ | |
939 | static int | |
940 | rcu_torture_writer(void *arg) | |
941 | { | |
9efafb88 | 942 | bool can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal(); |
4bb3c5f4 | 943 | int expediting = 0; |
a48f3fad PM |
944 | unsigned long gp_snap; |
945 | bool gp_cond1 = gp_cond, gp_exp1 = gp_exp, gp_normal1 = gp_normal; | |
f0bf8fab | 946 | bool gp_sync1 = gp_sync; |
a241ec65 | 947 | int i; |
a241ec65 PM |
948 | struct rcu_torture *rp; |
949 | struct rcu_torture *old_rp; | |
51b1130e | 950 | static DEFINE_TORTURE_RANDOM(rand); |
f0bf8fab PM |
951 | int synctype[] = { RTWS_DEF_FREE, RTWS_EXP_SYNC, |
952 | RTWS_COND_GET, RTWS_SYNC }; | |
a48f3fad | 953 | int nsynctypes = 0; |
a241ec65 | 954 | |
5ccf60f2 | 955 | VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); |
f7c0e6ad | 956 | if (!can_expedite) |
aa5a8988 | 957 | pr_alert("%s" TORTURE_FLAG |
f7c0e6ad | 958 | " GP expediting controlled from boot/sysfs for %s.\n", |
aa5a8988 | 959 | torture_type, cur_ops->name); |
dbdf65b1 | 960 | |
a48f3fad | 961 | /* Initialize synctype[] array. If none set, take default. */ |
c136f991 | 962 | if (!gp_cond1 && !gp_exp1 && !gp_normal1 && !gp_sync1) |
f0bf8fab | 963 | gp_cond1 = gp_exp1 = gp_normal1 = gp_sync1 = true; |
db0c1a8a | 964 | if (gp_cond1 && cur_ops->get_state && cur_ops->cond_sync) { |
a48f3fad | 965 | synctype[nsynctypes++] = RTWS_COND_GET; |
db0c1a8a PM |
966 | pr_info("%s: Testing conditional GPs.\n", __func__); |
967 | } else if (gp_cond && (!cur_ops->get_state || !cur_ops->cond_sync)) { | |
e0d31a34 | 968 | pr_alert("%s: gp_cond without primitives.\n", __func__); |
db0c1a8a PM |
969 | } |
970 | if (gp_exp1 && cur_ops->exp_sync) { | |
a48f3fad | 971 | synctype[nsynctypes++] = RTWS_EXP_SYNC; |
db0c1a8a PM |
972 | pr_info("%s: Testing expedited GPs.\n", __func__); |
973 | } else if (gp_exp && !cur_ops->exp_sync) { | |
e0d31a34 | 974 | pr_alert("%s: gp_exp without primitives.\n", __func__); |
db0c1a8a PM |
975 | } |
976 | if (gp_normal1 && cur_ops->deferred_free) { | |
a48f3fad | 977 | synctype[nsynctypes++] = RTWS_DEF_FREE; |
db0c1a8a PM |
978 | pr_info("%s: Testing asynchronous GPs.\n", __func__); |
979 | } else if (gp_normal && !cur_ops->deferred_free) { | |
e0d31a34 | 980 | pr_alert("%s: gp_normal without primitives.\n", __func__); |
db0c1a8a PM |
981 | } |
982 | if (gp_sync1 && cur_ops->sync) { | |
f0bf8fab | 983 | synctype[nsynctypes++] = RTWS_SYNC; |
db0c1a8a PM |
984 | pr_info("%s: Testing normal GPs.\n", __func__); |
985 | } else if (gp_sync && !cur_ops->sync) { | |
e0d31a34 | 986 | pr_alert("%s: gp_sync without primitives.\n", __func__); |
db0c1a8a | 987 | } |
a48f3fad PM |
988 | if (WARN_ONCE(nsynctypes == 0, |
989 | "rcu_torture_writer: No update-side primitives.\n")) { | |
f0bf8fab PM |
990 | /* |
991 | * No updates primitives, so don't try updating. | |
992 | * The resulting test won't be testing much, hence the | |
993 | * above WARN_ONCE(). | |
994 | */ | |
a48f3fad PM |
995 | rcu_torture_writer_state = RTWS_STOPPING; |
996 | torture_kthread_stopping("rcu_torture_writer"); | |
997 | } | |
998 | ||
a241ec65 | 999 | do { |
ad0dc7f9 | 1000 | rcu_torture_writer_state = RTWS_FIXED_DELAY; |
a241ec65 | 1001 | schedule_timeout_uninterruptible(1); |
a71fca58 PM |
1002 | rp = rcu_torture_alloc(); |
1003 | if (rp == NULL) | |
a241ec65 PM |
1004 | continue; |
1005 | rp->rtort_pipe_count = 0; | |
ad0dc7f9 | 1006 | rcu_torture_writer_state = RTWS_DELAY; |
51b1130e | 1007 | udelay(torture_random(&rand) & 0x3ff); |
ad0dc7f9 | 1008 | rcu_torture_writer_state = RTWS_REPLACE; |
0ddea0ea PM |
1009 | old_rp = rcu_dereference_check(rcu_torture_current, |
1010 | current == writer_task); | |
996417d2 | 1011 | rp->rtort_mbtest = 1; |
a241ec65 | 1012 | rcu_assign_pointer(rcu_torture_current, rp); |
9b2619af | 1013 | smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ |
c8e5b163 | 1014 | if (old_rp) { |
a241ec65 PM |
1015 | i = old_rp->rtort_pipe_count; |
1016 | if (i > RCU_TORTURE_PIPE_LEN) | |
1017 | i = RCU_TORTURE_PIPE_LEN; | |
1018 | atomic_inc(&rcu_torture_wcount[i]); | |
20248910 PM |
1019 | WRITE_ONCE(old_rp->rtort_pipe_count, |
1020 | old_rp->rtort_pipe_count + 1); | |
a48f3fad PM |
1021 | switch (synctype[torture_random(&rand) % nsynctypes]) { |
1022 | case RTWS_DEF_FREE: | |
ad0dc7f9 | 1023 | rcu_torture_writer_state = RTWS_DEF_FREE; |
2ec1f2d9 | 1024 | cur_ops->deferred_free(old_rp); |
a48f3fad PM |
1025 | break; |
1026 | case RTWS_EXP_SYNC: | |
ad0dc7f9 | 1027 | rcu_torture_writer_state = RTWS_EXP_SYNC; |
2ec1f2d9 | 1028 | cur_ops->exp_sync(); |
a48f3fad PM |
1029 | rcu_torture_pipe_update(old_rp); |
1030 | break; | |
1031 | case RTWS_COND_GET: | |
1032 | rcu_torture_writer_state = RTWS_COND_GET; | |
1033 | gp_snap = cur_ops->get_state(); | |
1034 | i = torture_random(&rand) % 16; | |
1035 | if (i != 0) | |
1036 | schedule_timeout_interruptible(i); | |
1037 | udelay(torture_random(&rand) % 1000); | |
1038 | rcu_torture_writer_state = RTWS_COND_SYNC; | |
1039 | cur_ops->cond_sync(gp_snap); | |
1040 | rcu_torture_pipe_update(old_rp); | |
1041 | break; | |
f0bf8fab PM |
1042 | case RTWS_SYNC: |
1043 | rcu_torture_writer_state = RTWS_SYNC; | |
1044 | cur_ops->sync(); | |
1045 | rcu_torture_pipe_update(old_rp); | |
1046 | break; | |
a48f3fad PM |
1047 | default: |
1048 | WARN_ON_ONCE(1); | |
1049 | break; | |
2ec1f2d9 | 1050 | } |
a241ec65 | 1051 | } |
1b27291b PM |
1052 | WRITE_ONCE(rcu_torture_current_version, |
1053 | rcu_torture_current_version + 1); | |
4bb3c5f4 PM |
1054 | /* Cycle through nesting levels of rcu_expedite_gp() calls. */ |
1055 | if (can_expedite && | |
1056 | !(torture_random(&rand) & 0xff & (!!expediting - 1))) { | |
1057 | WARN_ON_ONCE(expediting == 0 && rcu_gp_is_expedited()); | |
1058 | if (expediting >= 0) | |
1059 | rcu_expedite_gp(); | |
1060 | else | |
1061 | rcu_unexpedite_gp(); | |
1062 | if (++expediting > 3) | |
1063 | expediting = -expediting; | |
f7c0e6ad PM |
1064 | } else if (!can_expedite) { /* Disabled during boot, recheck. */ |
1065 | can_expedite = !rcu_gp_is_expedited() && | |
1066 | !rcu_gp_is_normal(); | |
4bb3c5f4 | 1067 | } |
ad0dc7f9 | 1068 | rcu_torture_writer_state = RTWS_STUTTER; |
e8516c64 | 1069 | if (stutter_wait("rcu_torture_writer") && |
5eabea59 | 1070 | !READ_ONCE(rcu_fwd_cb_nodelay) && |
3432d765 | 1071 | !cur_ops->slow_gps && |
59ee0326 PM |
1072 | !torture_must_stop() && |
1073 | rcu_inkernel_boot_has_ended()) | |
474e59b4 | 1074 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) |
e8516c64 PM |
1075 | if (list_empty(&rcu_tortures[i].rtort_free) && |
1076 | rcu_access_pointer(rcu_torture_current) != | |
34aa34b8 PM |
1077 | &rcu_tortures[i]) { |
1078 | rcu_ftrace_dump(DUMP_ALL); | |
e8516c64 | 1079 | WARN(1, "%s: rtort_pipe_count: %d\n", __func__, rcu_tortures[i].rtort_pipe_count); |
34aa34b8 | 1080 | } |
36970bb9 | 1081 | } while (!torture_must_stop()); |
4bb3c5f4 PM |
1082 | /* Reset expediting back to unexpedited. */ |
1083 | if (expediting > 0) | |
1084 | expediting = -expediting; | |
1085 | while (can_expedite && expediting++ < 0) | |
1086 | rcu_unexpedite_gp(); | |
1087 | WARN_ON_ONCE(can_expedite && rcu_gp_is_expedited()); | |
f7c0e6ad PM |
1088 | if (!can_expedite) |
1089 | pr_alert("%s" TORTURE_FLAG | |
1090 | " Dynamic grace-period expediting was disabled.\n", | |
1091 | torture_type); | |
ad0dc7f9 | 1092 | rcu_torture_writer_state = RTWS_STOPPING; |
7fafaac5 | 1093 | torture_kthread_stopping("rcu_torture_writer"); |
a241ec65 PM |
1094 | return 0; |
1095 | } | |
1096 | ||
b772e1dd JT |
1097 | /* |
1098 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random | |
1099 | * delay between calls. | |
1100 | */ | |
1101 | static int | |
1102 | rcu_torture_fakewriter(void *arg) | |
1103 | { | |
51b1130e | 1104 | DEFINE_TORTURE_RANDOM(rand); |
b772e1dd | 1105 | |
5ccf60f2 | 1106 | VERBOSE_TOROUT_STRING("rcu_torture_fakewriter task started"); |
d277d868 | 1107 | set_user_nice(current, MAX_NICE); |
b772e1dd JT |
1108 | |
1109 | do { | |
51b1130e PM |
1110 | schedule_timeout_uninterruptible(1 + torture_random(&rand)%10); |
1111 | udelay(torture_random(&rand) & 0x3ff); | |
72472a02 | 1112 | if (cur_ops->cb_barrier != NULL && |
51b1130e | 1113 | torture_random(&rand) % (nfakewriters * 8) == 0) { |
72472a02 | 1114 | cur_ops->cb_barrier(); |
2ec1f2d9 | 1115 | } else if (gp_normal == gp_exp) { |
eb033993 | 1116 | if (cur_ops->sync && torture_random(&rand) & 0x80) |
2ec1f2d9 | 1117 | cur_ops->sync(); |
eb033993 | 1118 | else if (cur_ops->exp_sync) |
2ec1f2d9 | 1119 | cur_ops->exp_sync(); |
eb033993 | 1120 | } else if (gp_normal && cur_ops->sync) { |
72472a02 | 1121 | cur_ops->sync(); |
eb033993 | 1122 | } else if (cur_ops->exp_sync) { |
2ec1f2d9 PM |
1123 | cur_ops->exp_sync(); |
1124 | } | |
628edaa5 | 1125 | stutter_wait("rcu_torture_fakewriter"); |
36970bb9 | 1126 | } while (!torture_must_stop()); |
b772e1dd | 1127 | |
7fafaac5 | 1128 | torture_kthread_stopping("rcu_torture_fakewriter"); |
b772e1dd JT |
1129 | return 0; |
1130 | } | |
1131 | ||
f34c8585 PM |
1132 | static void rcu_torture_timer_cb(struct rcu_head *rhp) |
1133 | { | |
1134 | kfree(rhp); | |
1135 | } | |
1136 | ||
0729fbf3 | 1137 | /* |
2397d072 PM |
1138 | * Do one extension of an RCU read-side critical section using the |
1139 | * current reader state in readstate (set to zero for initial entry | |
1140 | * to extended critical section), set the new state as specified by | |
1141 | * newstate (set to zero for final exit from extended critical section), | |
1142 | * and random-number-generator state in trsp. If this is neither the | |
1143 | * beginning or end of the critical section and if there was actually a | |
1144 | * change, do a ->read_delay(). | |
0729fbf3 | 1145 | */ |
2397d072 | 1146 | static void rcutorture_one_extend(int *readstate, int newstate, |
c116dba6 PM |
1147 | struct torture_random_state *trsp, |
1148 | struct rt_read_seg *rtrsp) | |
2397d072 PM |
1149 | { |
1150 | int idxnew = -1; | |
1151 | int idxold = *readstate; | |
1152 | int statesnew = ~*readstate & newstate; | |
1153 | int statesold = *readstate & ~newstate; | |
1154 | ||
1155 | WARN_ON_ONCE(idxold < 0); | |
1156 | WARN_ON_ONCE((idxold >> RCUTORTURE_RDR_SHIFT) > 1); | |
c116dba6 | 1157 | rtrsp->rt_readstate = newstate; |
2397d072 PM |
1158 | |
1159 | /* First, put new protection in place to avoid critical-section gap. */ | |
1160 | if (statesnew & RCUTORTURE_RDR_BH) | |
1161 | local_bh_disable(); | |
1162 | if (statesnew & RCUTORTURE_RDR_IRQ) | |
1163 | local_irq_disable(); | |
1164 | if (statesnew & RCUTORTURE_RDR_PREEMPT) | |
1165 | preempt_disable(); | |
2ceebc03 PM |
1166 | if (statesnew & RCUTORTURE_RDR_RBH) |
1167 | rcu_read_lock_bh(); | |
1168 | if (statesnew & RCUTORTURE_RDR_SCHED) | |
1169 | rcu_read_lock_sched(); | |
2397d072 PM |
1170 | if (statesnew & RCUTORTURE_RDR_RCU) |
1171 | idxnew = cur_ops->readlock() << RCUTORTURE_RDR_SHIFT; | |
1172 | ||
1173 | /* Next, remove old protection, irq first due to bh conflict. */ | |
1174 | if (statesold & RCUTORTURE_RDR_IRQ) | |
1175 | local_irq_enable(); | |
1176 | if (statesold & RCUTORTURE_RDR_BH) | |
1177 | local_bh_enable(); | |
1178 | if (statesold & RCUTORTURE_RDR_PREEMPT) | |
1179 | preempt_enable(); | |
2ceebc03 PM |
1180 | if (statesold & RCUTORTURE_RDR_RBH) |
1181 | rcu_read_unlock_bh(); | |
1182 | if (statesold & RCUTORTURE_RDR_SCHED) | |
1183 | rcu_read_unlock_sched(); | |
2397d072 PM |
1184 | if (statesold & RCUTORTURE_RDR_RCU) |
1185 | cur_ops->readunlock(idxold >> RCUTORTURE_RDR_SHIFT); | |
1186 | ||
1187 | /* Delay if neither beginning nor end and there was a change. */ | |
1188 | if ((statesnew || statesold) && *readstate && newstate) | |
c116dba6 | 1189 | cur_ops->read_delay(trsp, rtrsp); |
2397d072 PM |
1190 | |
1191 | /* Update the reader state. */ | |
1192 | if (idxnew == -1) | |
1193 | idxnew = idxold & ~RCUTORTURE_RDR_MASK; | |
1194 | WARN_ON_ONCE(idxnew < 0); | |
1195 | WARN_ON_ONCE((idxnew >> RCUTORTURE_RDR_SHIFT) > 1); | |
1196 | *readstate = idxnew | newstate; | |
1197 | WARN_ON_ONCE((*readstate >> RCUTORTURE_RDR_SHIFT) < 0); | |
1198 | WARN_ON_ONCE((*readstate >> RCUTORTURE_RDR_SHIFT) > 1); | |
1199 | } | |
1200 | ||
1201 | /* Return the biggest extendables mask given current RCU and boot parameters. */ | |
1202 | static int rcutorture_extend_mask_max(void) | |
1203 | { | |
1204 | int mask; | |
1205 | ||
1206 | WARN_ON_ONCE(extendables & ~RCUTORTURE_MAX_EXTEND); | |
1207 | mask = extendables & RCUTORTURE_MAX_EXTEND & cur_ops->extendables; | |
1208 | mask = mask | RCUTORTURE_RDR_RCU; | |
1209 | return mask; | |
1210 | } | |
1211 | ||
1212 | /* Return a random protection state mask, but with at least one bit set. */ | |
1213 | static int | |
1214 | rcutorture_extend_mask(int oldmask, struct torture_random_state *trsp) | |
1215 | { | |
1216 | int mask = rcutorture_extend_mask_max(); | |
bf1bef50 | 1217 | unsigned long randmask1 = torture_random(trsp) >> 8; |
c116dba6 | 1218 | unsigned long randmask2 = randmask1 >> 3; |
2397d072 PM |
1219 | |
1220 | WARN_ON_ONCE(mask >> RCUTORTURE_RDR_SHIFT); | |
a3b0e1e5 | 1221 | /* Mostly only one bit (need preemption!), sometimes lots of bits. */ |
c116dba6 | 1222 | if (!(randmask1 & 0x7)) |
bf1bef50 PM |
1223 | mask = mask & randmask2; |
1224 | else | |
1225 | mask = mask & (1 << (randmask2 % RCUTORTURE_RDR_NBITS)); | |
2ceebc03 | 1226 | /* Can't enable bh w/irq disabled. */ |
2397d072 | 1227 | if ((mask & RCUTORTURE_RDR_IRQ) && |
2ceebc03 PM |
1228 | ((!(mask & RCUTORTURE_RDR_BH) && (oldmask & RCUTORTURE_RDR_BH)) || |
1229 | (!(mask & RCUTORTURE_RDR_RBH) && (oldmask & RCUTORTURE_RDR_RBH)))) | |
1230 | mask |= RCUTORTURE_RDR_BH | RCUTORTURE_RDR_RBH; | |
2397d072 PM |
1231 | return mask ?: RCUTORTURE_RDR_RCU; |
1232 | } | |
1233 | ||
1234 | /* | |
1235 | * Do a randomly selected number of extensions of an existing RCU read-side | |
1236 | * critical section. | |
1237 | */ | |
c116dba6 PM |
1238 | static struct rt_read_seg * |
1239 | rcutorture_loop_extend(int *readstate, struct torture_random_state *trsp, | |
1240 | struct rt_read_seg *rtrsp) | |
2397d072 PM |
1241 | { |
1242 | int i; | |
c116dba6 | 1243 | int j; |
2397d072 PM |
1244 | int mask = rcutorture_extend_mask_max(); |
1245 | ||
1246 | WARN_ON_ONCE(!*readstate); /* -Existing- RCU read-side critsect! */ | |
1247 | if (!((mask - 1) & mask)) | |
c116dba6 PM |
1248 | return rtrsp; /* Current RCU reader not extendable. */ |
1249 | /* Bias towards larger numbers of loops. */ | |
1250 | i = (torture_random(trsp) >> 3); | |
1251 | i = ((i | (i >> 3)) & RCUTORTURE_RDR_MAX_LOOPS) + 1; | |
1252 | for (j = 0; j < i; j++) { | |
2397d072 | 1253 | mask = rcutorture_extend_mask(*readstate, trsp); |
c116dba6 | 1254 | rcutorture_one_extend(readstate, mask, trsp, &rtrsp[j]); |
2397d072 | 1255 | } |
c116dba6 | 1256 | return &rtrsp[j]; |
2397d072 PM |
1257 | } |
1258 | ||
6b06aa72 PM |
1259 | /* |
1260 | * Do one read-side critical section, returning false if there was | |
1261 | * no data to read. Can be invoked both from process context and | |
1262 | * from a timer handler. | |
1263 | */ | |
1264 | static bool rcu_torture_one_read(struct torture_random_state *trsp) | |
0729fbf3 | 1265 | { |
c116dba6 | 1266 | int i; |
917963d0 | 1267 | unsigned long started; |
6b80da42 | 1268 | unsigned long completed; |
2397d072 | 1269 | int newstate; |
0729fbf3 PM |
1270 | struct rcu_torture *p; |
1271 | int pipe_count; | |
2397d072 | 1272 | int readstate = 0; |
c116dba6 PM |
1273 | struct rt_read_seg rtseg[RCUTORTURE_RDR_MAX_SEGS] = { { 0 } }; |
1274 | struct rt_read_seg *rtrsp = &rtseg[0]; | |
1275 | struct rt_read_seg *rtrsp1; | |
52494535 | 1276 | unsigned long long ts; |
0729fbf3 | 1277 | |
2397d072 | 1278 | newstate = rcutorture_extend_mask(readstate, trsp); |
c116dba6 | 1279 | rcutorture_one_extend(&readstate, newstate, trsp, rtrsp++); |
17ef2fe9 | 1280 | started = cur_ops->get_gp_seq(); |
e4aa0da3 | 1281 | ts = rcu_trace_clock_local(); |
632ee200 | 1282 | p = rcu_dereference_check(rcu_torture_current, |
632ee200 PM |
1283 | rcu_read_lock_bh_held() || |
1284 | rcu_read_lock_sched_held() || | |
5be5d1a1 PM |
1285 | srcu_read_lock_held(srcu_ctlp) || |
1286 | torturing_tasks()); | |
0729fbf3 | 1287 | if (p == NULL) { |
6b06aa72 | 1288 | /* Wait for rcu_torture_writer to get underway */ |
c116dba6 | 1289 | rcutorture_one_extend(&readstate, 0, trsp, rtrsp); |
6b06aa72 | 1290 | return false; |
0729fbf3 PM |
1291 | } |
1292 | if (p->rtort_mbtest == 0) | |
1293 | atomic_inc(&n_rcu_torture_mberror); | |
c116dba6 | 1294 | rtrsp = rcutorture_loop_extend(&readstate, trsp, rtrsp); |
0729fbf3 | 1295 | preempt_disable(); |
20248910 | 1296 | pipe_count = READ_ONCE(p->rtort_pipe_count); |
0729fbf3 PM |
1297 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { |
1298 | /* Should not happen, but... */ | |
1299 | pipe_count = RCU_TORTURE_PIPE_LEN; | |
1300 | } | |
17ef2fe9 | 1301 | completed = cur_ops->get_gp_seq(); |
52494535 | 1302 | if (pipe_count > 1) { |
6b06aa72 PM |
1303 | do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, |
1304 | ts, started, completed); | |
274529ba | 1305 | rcu_ftrace_dump(DUMP_ALL); |
52494535 | 1306 | } |
dd17c8f7 | 1307 | __this_cpu_inc(rcu_torture_count[pipe_count]); |
d7219312 | 1308 | completed = rcutorture_seq_diff(completed, started); |
0729fbf3 PM |
1309 | if (completed > RCU_TORTURE_PIPE_LEN) { |
1310 | /* Should not happen, but... */ | |
1311 | completed = RCU_TORTURE_PIPE_LEN; | |
1312 | } | |
dd17c8f7 | 1313 | __this_cpu_inc(rcu_torture_batch[completed]); |
0729fbf3 | 1314 | preempt_enable(); |
c116dba6 | 1315 | rcutorture_one_extend(&readstate, 0, trsp, rtrsp); |
2397d072 | 1316 | WARN_ON_ONCE(readstate & RCUTORTURE_RDR_MASK); |
c116dba6 PM |
1317 | |
1318 | /* If error or close call, record the sequence of reader protections. */ | |
1319 | if ((pipe_count > 1 || completed > 1) && !xchg(&err_segs_recorded, 1)) { | |
1320 | i = 0; | |
1321 | for (rtrsp1 = &rtseg[0]; rtrsp1 < rtrsp; rtrsp1++) | |
1322 | err_segs[i++] = *rtrsp1; | |
1323 | rt_read_nsegs = i; | |
1324 | } | |
1325 | ||
6b06aa72 PM |
1326 | return true; |
1327 | } | |
1328 | ||
3025520e PM |
1329 | static DEFINE_TORTURE_RANDOM_PERCPU(rcu_torture_timer_rand); |
1330 | ||
0729fbf3 PM |
1331 | /* |
1332 | * RCU torture reader from timer handler. Dereferences rcu_torture_current, | |
1333 | * incrementing the corresponding element of the pipeline array. The | |
1334 | * counter in the element should never be greater than 1, otherwise, the | |
1335 | * RCU implementation is broken. | |
1336 | */ | |
fd30b717 | 1337 | static void rcu_torture_timer(struct timer_list *unused) |
0729fbf3 | 1338 | { |
8da9a595 | 1339 | atomic_long_inc(&n_rcu_torture_timers); |
241b4252 | 1340 | (void)rcu_torture_one_read(this_cpu_ptr(&rcu_torture_timer_rand)); |
f34c8585 PM |
1341 | |
1342 | /* Test call_rcu() invocation from interrupt handler. */ | |
1343 | if (cur_ops->call) { | |
1344 | struct rcu_head *rhp = kmalloc(sizeof(*rhp), GFP_NOWAIT); | |
1345 | ||
1346 | if (rhp) | |
1347 | cur_ops->call(rhp, rcu_torture_timer_cb); | |
1348 | } | |
0729fbf3 PM |
1349 | } |
1350 | ||
a241ec65 PM |
1351 | /* |
1352 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, | |
1353 | * incrementing the corresponding element of the pipeline array. The | |
1354 | * counter in the element should never be greater than 1, otherwise, the | |
1355 | * RCU implementation is broken. | |
1356 | */ | |
1357 | static int | |
1358 | rcu_torture_reader(void *arg) | |
1359 | { | |
444da518 | 1360 | unsigned long lastsleep = jiffies; |
c04dd09b PM |
1361 | long myid = (long)arg; |
1362 | int mynumonline = myid; | |
51b1130e | 1363 | DEFINE_TORTURE_RANDOM(rand); |
0729fbf3 | 1364 | struct timer_list t; |
a241ec65 | 1365 | |
5ccf60f2 | 1366 | VERBOSE_TOROUT_STRING("rcu_torture_reader task started"); |
d277d868 | 1367 | set_user_nice(current, MAX_NICE); |
0acc512c | 1368 | if (irqreader && cur_ops->irq_capable) |
fd30b717 | 1369 | timer_setup_on_stack(&t, rcu_torture_timer, 0); |
d38e6dc6 | 1370 | tick_dep_set_task(current, TICK_DEP_BIT_RCU); |
a241ec65 | 1371 | do { |
0acc512c | 1372 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 1373 | if (!timer_pending(&t)) |
6155fec9 | 1374 | mod_timer(&t, jiffies + 1); |
0729fbf3 | 1375 | } |
d38e6dc6 | 1376 | if (!rcu_torture_one_read(&rand) && !torture_must_stop()) |
a241ec65 | 1377 | schedule_timeout_interruptible(HZ); |
d38e6dc6 | 1378 | if (time_after(jiffies, lastsleep) && !torture_must_stop()) { |
444da518 PM |
1379 | schedule_timeout_interruptible(1); |
1380 | lastsleep = jiffies + 10; | |
1381 | } | |
c04dd09b PM |
1382 | while (num_online_cpus() < mynumonline && !torture_must_stop()) |
1383 | schedule_timeout_interruptible(HZ / 5); | |
628edaa5 | 1384 | stutter_wait("rcu_torture_reader"); |
36970bb9 | 1385 | } while (!torture_must_stop()); |
424c1b68 | 1386 | if (irqreader && cur_ops->irq_capable) { |
0729fbf3 | 1387 | del_timer_sync(&t); |
424c1b68 TG |
1388 | destroy_timer_on_stack(&t); |
1389 | } | |
d38e6dc6 | 1390 | tick_dep_clear_task(current, TICK_DEP_BIT_RCU); |
7fafaac5 | 1391 | torture_kthread_stopping("rcu_torture_reader"); |
a241ec65 PM |
1392 | return 0; |
1393 | } | |
1394 | ||
1395 | /* | |
eea203fe JP |
1396 | * Print torture statistics. Caller must ensure that there is only |
1397 | * one call to this function at a given time!!! This is normally | |
1398 | * accomplished by relying on the module system to only have one copy | |
1399 | * of the module loaded, and then by giving the rcu_torture_stats | |
1400 | * kthread full control (or the init/cleanup functions when rcu_torture_stats | |
1401 | * thread is not running). | |
a241ec65 | 1402 | */ |
d1008950 | 1403 | static void |
eea203fe | 1404 | rcu_torture_stats_print(void) |
a241ec65 | 1405 | { |
a241ec65 PM |
1406 | int cpu; |
1407 | int i; | |
1408 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
1409 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; | |
5396d31d | 1410 | struct rcu_torture *rtcp; |
ad0dc7f9 | 1411 | static unsigned long rtcv_snap = ULONG_MAX; |
0032f4e8 | 1412 | static bool splatted; |
4ffa6699 | 1413 | struct task_struct *wtp; |
a241ec65 | 1414 | |
0a945022 | 1415 | for_each_possible_cpu(cpu) { |
a241ec65 | 1416 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
f042a436 PM |
1417 | pipesummary[i] += READ_ONCE(per_cpu(rcu_torture_count, cpu)[i]); |
1418 | batchsummary[i] += READ_ONCE(per_cpu(rcu_torture_batch, cpu)[i]); | |
a241ec65 PM |
1419 | } |
1420 | } | |
1421 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { | |
1422 | if (pipesummary[i] != 0) | |
1423 | break; | |
1424 | } | |
eea203fe JP |
1425 | |
1426 | pr_alert("%s%s ", torture_type, TORTURE_FLAG); | |
5396d31d | 1427 | rtcp = rcu_access_pointer(rcu_torture_current); |
354ea05d | 1428 | pr_cont("rtc: %p %s: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", |
5396d31d PM |
1429 | rtcp, |
1430 | rtcp && !rcu_stall_is_suppressed_at_boot() ? "ver" : "VER", | |
eea203fe JP |
1431 | rcu_torture_current_version, |
1432 | list_empty(&rcu_torture_freelist), | |
1433 | atomic_read(&n_rcu_torture_alloc), | |
1434 | atomic_read(&n_rcu_torture_alloc_fail), | |
1435 | atomic_read(&n_rcu_torture_free)); | |
472213a6 | 1436 | pr_cont("rtmbe: %d rtbe: %ld rtbke: %ld rtbre: %ld ", |
eea203fe | 1437 | atomic_read(&n_rcu_torture_mberror), |
472213a6 | 1438 | n_rcu_torture_barrier_error, |
eea203fe JP |
1439 | n_rcu_torture_boost_ktrerror, |
1440 | n_rcu_torture_boost_rterror); | |
1441 | pr_cont("rtbf: %ld rtb: %ld nt: %ld ", | |
1442 | n_rcu_torture_boost_failure, | |
1443 | n_rcu_torture_boosts, | |
8da9a595 | 1444 | atomic_long_read(&n_rcu_torture_timers)); |
eea203fe | 1445 | torture_onoff_stats(); |
fc6f9c57 | 1446 | pr_cont("barrier: %ld/%ld:%ld\n", |
eea203fe JP |
1447 | n_barrier_successes, |
1448 | n_barrier_attempts, | |
1449 | n_rcu_torture_barrier_error); | |
1450 | ||
1451 | pr_alert("%s%s ", torture_type, TORTURE_FLAG); | |
8b5ddf8b PM |
1452 | if (atomic_read(&n_rcu_torture_mberror) || |
1453 | n_rcu_torture_barrier_error || n_rcu_torture_boost_ktrerror || | |
1454 | n_rcu_torture_boost_rterror || n_rcu_torture_boost_failure || | |
fae4b54f | 1455 | i > 1) { |
eea203fe | 1456 | pr_cont("%s", "!!! "); |
996417d2 | 1457 | atomic_inc(&n_rcu_torture_error); |
8b5ddf8b PM |
1458 | WARN_ON_ONCE(atomic_read(&n_rcu_torture_mberror)); |
1459 | WARN_ON_ONCE(n_rcu_torture_barrier_error); // rcu_barrier() | |
1460 | WARN_ON_ONCE(n_rcu_torture_boost_ktrerror); // no boost kthread | |
1461 | WARN_ON_ONCE(n_rcu_torture_boost_rterror); // can't set RT prio | |
1462 | WARN_ON_ONCE(n_rcu_torture_boost_failure); // RCU boost failed | |
1463 | WARN_ON_ONCE(i > 1); // Too-short grace period | |
996417d2 | 1464 | } |
eea203fe | 1465 | pr_cont("Reader Pipe: "); |
a241ec65 | 1466 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
eea203fe JP |
1467 | pr_cont(" %ld", pipesummary[i]); |
1468 | pr_cont("\n"); | |
1469 | ||
1470 | pr_alert("%s%s ", torture_type, TORTURE_FLAG); | |
1471 | pr_cont("Reader Batch: "); | |
72e9bb54 | 1472 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
eea203fe JP |
1473 | pr_cont(" %ld", batchsummary[i]); |
1474 | pr_cont("\n"); | |
1475 | ||
1476 | pr_alert("%s%s ", torture_type, TORTURE_FLAG); | |
1477 | pr_cont("Free-Block Circulation: "); | |
a241ec65 | 1478 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
eea203fe | 1479 | pr_cont(" %d", atomic_read(&rcu_torture_wcount[i])); |
a241ec65 | 1480 | } |
eea203fe JP |
1481 | pr_cont("\n"); |
1482 | ||
c8e5b163 | 1483 | if (cur_ops->stats) |
eea203fe | 1484 | cur_ops->stats(); |
ad0dc7f9 | 1485 | if (rtcv_snap == rcu_torture_current_version && |
5396d31d PM |
1486 | rcu_access_pointer(rcu_torture_current) && |
1487 | !rcu_stall_is_suppressed()) { | |
7f6733c3 | 1488 | int __maybe_unused flags = 0; |
aebc8264 | 1489 | unsigned long __maybe_unused gp_seq = 0; |
ad0dc7f9 PM |
1490 | |
1491 | rcutorture_get_gp_data(cur_ops->ttype, | |
aebc8264 | 1492 | &flags, &gp_seq); |
7f6733c3 | 1493 | srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, |
aebc8264 | 1494 | &flags, &gp_seq); |
4ffa6699 | 1495 | wtp = READ_ONCE(writer_task); |
aebc8264 | 1496 | pr_alert("??? Writer stall state %s(%d) g%lu f%#x ->state %#lx cpu %d\n", |
18aff33e | 1497 | rcu_torture_writer_state_getname(), |
aebc8264 | 1498 | rcu_torture_writer_state, gp_seq, flags, |
808de39c PM |
1499 | wtp == NULL ? ~0UL : wtp->state, |
1500 | wtp == NULL ? -1 : (int)task_cpu(wtp)); | |
0032f4e8 PM |
1501 | if (!splatted && wtp) { |
1502 | sched_show_task(wtp); | |
1503 | splatted = true; | |
1504 | } | |
afea227f | 1505 | show_rcu_gp_kthreads(); |
274529ba | 1506 | rcu_ftrace_dump(DUMP_ALL); |
ad0dc7f9 PM |
1507 | } |
1508 | rtcv_snap = rcu_torture_current_version; | |
a241ec65 PM |
1509 | } |
1510 | ||
a241ec65 PM |
1511 | /* |
1512 | * Periodically prints torture statistics, if periodic statistics printing | |
1513 | * was specified via the stat_interval module parameter. | |
a241ec65 PM |
1514 | */ |
1515 | static int | |
1516 | rcu_torture_stats(void *arg) | |
1517 | { | |
5ccf60f2 | 1518 | VERBOSE_TOROUT_STRING("rcu_torture_stats task started"); |
a241ec65 PM |
1519 | do { |
1520 | schedule_timeout_interruptible(stat_interval * HZ); | |
1521 | rcu_torture_stats_print(); | |
f67a3356 | 1522 | torture_shutdown_absorb("rcu_torture_stats"); |
36970bb9 | 1523 | } while (!torture_must_stop()); |
7fafaac5 | 1524 | torture_kthread_stopping("rcu_torture_stats"); |
d120f65f PM |
1525 | return 0; |
1526 | } | |
1527 | ||
eac45e58 | 1528 | static void |
e66c33d5 | 1529 | rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag) |
95c38322 | 1530 | { |
2caa1e44 PM |
1531 | pr_alert("%s" TORTURE_FLAG |
1532 | "--- %s: nreaders=%d nfakewriters=%d " | |
1533 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " | |
1534 | "shuffle_interval=%d stutter=%d irqreader=%d " | |
1535 | "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " | |
1536 | "test_boost=%d/%d test_boost_interval=%d " | |
1537 | "test_boost_duration=%d shutdown_secs=%d " | |
2b1516e5 | 1538 | "stall_cpu=%d stall_cpu_holdoff=%d stall_cpu_irqsoff=%d " |
67afeed2 | 1539 | "n_barrier_cbs=%d " |
2caa1e44 PM |
1540 | "onoff_interval=%d onoff_holdoff=%d\n", |
1541 | torture_type, tag, nrealreaders, nfakewriters, | |
1542 | stat_interval, verbose, test_no_idle_hz, shuffle_interval, | |
1543 | stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, | |
1544 | test_boost, cur_ops->can_boost, | |
1545 | test_boost_interval, test_boost_duration, shutdown_secs, | |
2b1516e5 | 1546 | stall_cpu, stall_cpu_holdoff, stall_cpu_irqsoff, |
67afeed2 | 1547 | n_barrier_cbs, |
2caa1e44 | 1548 | onoff_interval, onoff_holdoff); |
95c38322 PM |
1549 | } |
1550 | ||
0ffd374b | 1551 | static int rcutorture_booster_cleanup(unsigned int cpu) |
8e8be45e PM |
1552 | { |
1553 | struct task_struct *t; | |
1554 | ||
1555 | if (boost_tasks[cpu] == NULL) | |
0ffd374b | 1556 | return 0; |
8e8be45e | 1557 | mutex_lock(&boost_mutex); |
8e8be45e PM |
1558 | t = boost_tasks[cpu]; |
1559 | boost_tasks[cpu] = NULL; | |
450efca7 | 1560 | rcu_torture_enable_rt_throttle(); |
8e8be45e PM |
1561 | mutex_unlock(&boost_mutex); |
1562 | ||
1563 | /* This must be outside of the mutex, otherwise deadlock! */ | |
9c029b86 | 1564 | torture_stop_kthread(rcu_torture_boost, t); |
0ffd374b | 1565 | return 0; |
8e8be45e PM |
1566 | } |
1567 | ||
0ffd374b | 1568 | static int rcutorture_booster_init(unsigned int cpu) |
8e8be45e PM |
1569 | { |
1570 | int retval; | |
1571 | ||
1572 | if (boost_tasks[cpu] != NULL) | |
1573 | return 0; /* Already created, nothing more to do. */ | |
1574 | ||
1575 | /* Don't allow time recalculation while creating a new task. */ | |
1576 | mutex_lock(&boost_mutex); | |
450efca7 | 1577 | rcu_torture_disable_rt_throttle(); |
5ccf60f2 | 1578 | VERBOSE_TOROUT_STRING("Creating rcu_torture_boost task"); |
1f288094 ED |
1579 | boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL, |
1580 | cpu_to_node(cpu), | |
1581 | "rcu_torture_boost"); | |
8e8be45e PM |
1582 | if (IS_ERR(boost_tasks[cpu])) { |
1583 | retval = PTR_ERR(boost_tasks[cpu]); | |
5ccf60f2 | 1584 | VERBOSE_TOROUT_STRING("rcu_torture_boost task create failed"); |
8e8be45e PM |
1585 | n_rcu_torture_boost_ktrerror++; |
1586 | boost_tasks[cpu] = NULL; | |
1587 | mutex_unlock(&boost_mutex); | |
1588 | return retval; | |
1589 | } | |
1590 | kthread_bind(boost_tasks[cpu], cpu); | |
1591 | wake_up_process(boost_tasks[cpu]); | |
1592 | mutex_unlock(&boost_mutex); | |
1593 | return 0; | |
1594 | } | |
1595 | ||
c13f3757 PM |
1596 | /* |
1597 | * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then | |
1598 | * induces a CPU stall for the time specified by stall_cpu. | |
1599 | */ | |
49fb4c62 | 1600 | static int rcu_torture_stall(void *args) |
c13f3757 PM |
1601 | { |
1602 | unsigned long stop_at; | |
1603 | ||
5ccf60f2 | 1604 | VERBOSE_TOROUT_STRING("rcu_torture_stall task started"); |
c13f3757 | 1605 | if (stall_cpu_holdoff > 0) { |
5ccf60f2 | 1606 | VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff"); |
c13f3757 | 1607 | schedule_timeout_interruptible(stall_cpu_holdoff * HZ); |
5ccf60f2 | 1608 | VERBOSE_TOROUT_STRING("rcu_torture_stall end holdoff"); |
c13f3757 PM |
1609 | } |
1610 | if (!kthread_should_stop()) { | |
622be33f | 1611 | stop_at = ktime_get_seconds() + stall_cpu; |
c13f3757 | 1612 | /* RCU CPU stall is expected behavior in following code. */ |
c13f3757 | 1613 | rcu_read_lock(); |
2b1516e5 PM |
1614 | if (stall_cpu_irqsoff) |
1615 | local_irq_disable(); | |
1616 | else | |
1617 | preempt_disable(); | |
1618 | pr_alert("rcu_torture_stall start on CPU %d.\n", | |
1619 | smp_processor_id()); | |
622be33f AB |
1620 | while (ULONG_CMP_LT((unsigned long)ktime_get_seconds(), |
1621 | stop_at)) | |
c13f3757 | 1622 | continue; /* Induce RCU CPU stall warning. */ |
2b1516e5 PM |
1623 | if (stall_cpu_irqsoff) |
1624 | local_irq_enable(); | |
1625 | else | |
1626 | preempt_enable(); | |
c13f3757 | 1627 | rcu_read_unlock(); |
2caa1e44 | 1628 | pr_alert("rcu_torture_stall end.\n"); |
c13f3757 | 1629 | } |
f67a3356 | 1630 | torture_shutdown_absorb("rcu_torture_stall"); |
c13f3757 PM |
1631 | while (!kthread_should_stop()) |
1632 | schedule_timeout_interruptible(10 * HZ); | |
1633 | return 0; | |
1634 | } | |
1635 | ||
1636 | /* Spawn CPU-stall kthread, if stall_cpu specified. */ | |
1637 | static int __init rcu_torture_stall_init(void) | |
1638 | { | |
c13f3757 PM |
1639 | if (stall_cpu <= 0) |
1640 | return 0; | |
47cf29b9 | 1641 | return torture_create_kthread(rcu_torture_stall, NULL, stall_task); |
c13f3757 PM |
1642 | } |
1643 | ||
9fdcb9af PM |
1644 | /* State structure for forward-progress self-propagating RCU callback. */ |
1645 | struct fwd_cb_state { | |
1646 | struct rcu_head rh; | |
1647 | int stop; | |
1648 | }; | |
1649 | ||
1650 | /* | |
1651 | * Forward-progress self-propagating RCU callback function. Because | |
1652 | * callbacks run from softirq, this function is an implicit RCU read-side | |
1653 | * critical section. | |
1654 | */ | |
1655 | static void rcu_torture_fwd_prog_cb(struct rcu_head *rhp) | |
1656 | { | |
1657 | struct fwd_cb_state *fcsp = container_of(rhp, struct fwd_cb_state, rh); | |
1658 | ||
1659 | if (READ_ONCE(fcsp->stop)) { | |
1660 | WRITE_ONCE(fcsp->stop, 2); | |
1661 | return; | |
1662 | } | |
1663 | cur_ops->call(&fcsp->rh, rcu_torture_fwd_prog_cb); | |
1664 | } | |
1665 | ||
48718485 PM |
1666 | /* State for continuous-flood RCU callbacks. */ |
1667 | struct rcu_fwd_cb { | |
1668 | struct rcu_head rh; | |
1669 | struct rcu_fwd_cb *rfc_next; | |
6b1b8325 | 1670 | struct rcu_fwd *rfc_rfp; |
48718485 PM |
1671 | int rfc_gps; |
1672 | }; | |
a289e608 | 1673 | |
48718485 PM |
1674 | #define MAX_FWD_CB_JIFFIES (8 * HZ) /* Maximum CB test duration. */ |
1675 | #define MIN_FWD_CB_LAUNDERS 3 /* This many CB invocations to count. */ | |
1676 | #define MIN_FWD_CBS_LAUNDERED 100 /* Number of counted CBs. */ | |
2e57bf97 | 1677 | #define FWD_CBS_HIST_DIV 10 /* Histogram buckets/second. */ |
a289e608 PM |
1678 | #define N_LAUNDERS_HIST (2 * MAX_FWD_CB_JIFFIES / (HZ / FWD_CBS_HIST_DIV)) |
1679 | ||
cd618d10 PM |
1680 | struct rcu_launder_hist { |
1681 | long n_launders; | |
1682 | unsigned long launder_gp_seq; | |
1683 | }; | |
48718485 | 1684 | |
a289e608 PM |
1685 | struct rcu_fwd { |
1686 | spinlock_t rcu_fwd_lock; | |
1687 | struct rcu_fwd_cb *rcu_fwd_cb_head; | |
1688 | struct rcu_fwd_cb **rcu_fwd_cb_tail; | |
1689 | long n_launders_cb; | |
1690 | unsigned long rcu_fwd_startat; | |
1691 | struct rcu_launder_hist n_launders_hist[N_LAUNDERS_HIST]; | |
1692 | unsigned long rcu_launder_gp_seq_start; | |
1693 | }; | |
1694 | ||
5155be99 | 1695 | struct rcu_fwd *rcu_fwds; |
a289e608 | 1696 | bool rcu_fwd_emergency_stop; |
48718485 | 1697 | |
6b1b8325 | 1698 | static void rcu_torture_fwd_cb_hist(struct rcu_fwd *rfp) |
1a682754 | 1699 | { |
cd618d10 PM |
1700 | unsigned long gps; |
1701 | unsigned long gps_old; | |
1a682754 PM |
1702 | int i; |
1703 | int j; | |
1704 | ||
6b1b8325 PM |
1705 | for (i = ARRAY_SIZE(rfp->n_launders_hist) - 1; i > 0; i--) |
1706 | if (rfp->n_launders_hist[i].n_launders > 0) | |
1a682754 | 1707 | break; |
73d665b1 | 1708 | pr_alert("%s: Callback-invocation histogram (duration %lu jiffies):", |
6b1b8325 PM |
1709 | __func__, jiffies - rfp->rcu_fwd_startat); |
1710 | gps_old = rfp->rcu_launder_gp_seq_start; | |
cd618d10 | 1711 | for (j = 0; j <= i; j++) { |
6b1b8325 | 1712 | gps = rfp->n_launders_hist[j].launder_gp_seq; |
cd618d10 | 1713 | pr_cont(" %ds/%d: %ld:%ld", |
a289e608 | 1714 | j + 1, FWD_CBS_HIST_DIV, |
6b1b8325 | 1715 | rfp->n_launders_hist[j].n_launders, |
cd618d10 PM |
1716 | rcutorture_seq_diff(gps, gps_old)); |
1717 | gps_old = gps; | |
1718 | } | |
1a682754 PM |
1719 | pr_cont("\n"); |
1720 | } | |
1721 | ||
48718485 PM |
1722 | /* Callback function for continuous-flood RCU callbacks. */ |
1723 | static void rcu_torture_fwd_cb_cr(struct rcu_head *rhp) | |
1724 | { | |
2667ccce | 1725 | unsigned long flags; |
48718485 PM |
1726 | int i; |
1727 | struct rcu_fwd_cb *rfcp = container_of(rhp, struct rcu_fwd_cb, rh); | |
1728 | struct rcu_fwd_cb **rfcpp; | |
6b1b8325 | 1729 | struct rcu_fwd *rfp = rfcp->rfc_rfp; |
48718485 PM |
1730 | |
1731 | rfcp->rfc_next = NULL; | |
1732 | rfcp->rfc_gps++; | |
6b1b8325 PM |
1733 | spin_lock_irqsave(&rfp->rcu_fwd_lock, flags); |
1734 | rfcpp = rfp->rcu_fwd_cb_tail; | |
1735 | rfp->rcu_fwd_cb_tail = &rfcp->rfc_next; | |
48718485 | 1736 | WRITE_ONCE(*rfcpp, rfcp); |
6b1b8325 PM |
1737 | WRITE_ONCE(rfp->n_launders_cb, rfp->n_launders_cb + 1); |
1738 | i = ((jiffies - rfp->rcu_fwd_startat) / (HZ / FWD_CBS_HIST_DIV)); | |
1739 | if (i >= ARRAY_SIZE(rfp->n_launders_hist)) | |
1740 | i = ARRAY_SIZE(rfp->n_launders_hist) - 1; | |
1741 | rfp->n_launders_hist[i].n_launders++; | |
1742 | rfp->n_launders_hist[i].launder_gp_seq = cur_ops->get_gp_seq(); | |
1743 | spin_unlock_irqrestore(&rfp->rcu_fwd_lock, flags); | |
2667ccce PM |
1744 | } |
1745 | ||
ab21f608 | 1746 | // Give the scheduler a chance, even on nohz_full CPUs. |
bd1bfc51 | 1747 | static void rcu_torture_fwd_prog_cond_resched(unsigned long iter) |
ab21f608 | 1748 | { |
90326f05 | 1749 | if (IS_ENABLED(CONFIG_PREEMPTION) && IS_ENABLED(CONFIG_NO_HZ_FULL)) { |
bd1bfc51 PM |
1750 | // Real call_rcu() floods hit userspace, so emulate that. |
1751 | if (need_resched() || (iter & 0xfff)) | |
ab21f608 | 1752 | schedule(); |
d38e6dc6 | 1753 | return; |
ab21f608 | 1754 | } |
d38e6dc6 PM |
1755 | // No userspace emulation: CB invocation throttles call_rcu() |
1756 | cond_resched(); | |
ab21f608 PM |
1757 | } |
1758 | ||
2667ccce PM |
1759 | /* |
1760 | * Free all callbacks on the rcu_fwd_cb_head list, either because the | |
1761 | * test is over or because we hit an OOM event. | |
1762 | */ | |
6764100b | 1763 | static unsigned long rcu_torture_fwd_prog_cbfree(struct rcu_fwd *rfp) |
2667ccce PM |
1764 | { |
1765 | unsigned long flags; | |
1766 | unsigned long freed = 0; | |
1767 | struct rcu_fwd_cb *rfcp; | |
1768 | ||
1769 | for (;;) { | |
6764100b PM |
1770 | spin_lock_irqsave(&rfp->rcu_fwd_lock, flags); |
1771 | rfcp = rfp->rcu_fwd_cb_head; | |
140e53f2 | 1772 | if (!rfcp) { |
6764100b | 1773 | spin_unlock_irqrestore(&rfp->rcu_fwd_lock, flags); |
2667ccce | 1774 | break; |
140e53f2 | 1775 | } |
6764100b PM |
1776 | rfp->rcu_fwd_cb_head = rfcp->rfc_next; |
1777 | if (!rfp->rcu_fwd_cb_head) | |
1778 | rfp->rcu_fwd_cb_tail = &rfp->rcu_fwd_cb_head; | |
1779 | spin_unlock_irqrestore(&rfp->rcu_fwd_lock, flags); | |
2667ccce PM |
1780 | kfree(rfcp); |
1781 | freed++; | |
bd1bfc51 | 1782 | rcu_torture_fwd_prog_cond_resched(freed); |
79ba7ff5 PM |
1783 | if (tick_nohz_full_enabled()) { |
1784 | local_irq_save(flags); | |
1785 | rcu_momentary_dyntick_idle(); | |
1786 | local_irq_restore(flags); | |
1787 | } | |
2667ccce | 1788 | } |
2667ccce | 1789 | return freed; |
48718485 PM |
1790 | } |
1791 | ||
6b3de7a1 | 1792 | /* Carry out need_resched()/cond_resched() forward-progress testing. */ |
6b1b8325 PM |
1793 | static void rcu_torture_fwd_prog_nr(struct rcu_fwd *rfp, |
1794 | int *tested, int *tested_tries) | |
1b27291b | 1795 | { |
119248be | 1796 | unsigned long cver; |
f4de46ed | 1797 | unsigned long dur; |
7c590fcc | 1798 | struct fwd_cb_state fcs; |
119248be | 1799 | unsigned long gps; |
1b27291b | 1800 | int idx; |
6b3de7a1 PM |
1801 | int sd; |
1802 | int sd4; | |
1803 | bool selfpropcb = false; | |
1804 | unsigned long stopat; | |
1805 | static DEFINE_TORTURE_RANDOM(trs); | |
1806 | ||
1807 | if (cur_ops->call && cur_ops->sync && cur_ops->cb_barrier) { | |
1808 | init_rcu_head_on_stack(&fcs.rh); | |
1809 | selfpropcb = true; | |
1810 | } | |
1811 | ||
1812 | /* Tight loop containing cond_resched(). */ | |
e8516c64 PM |
1813 | WRITE_ONCE(rcu_fwd_cb_nodelay, true); |
1814 | cur_ops->sync(); /* Later readers see above write. */ | |
6b3de7a1 PM |
1815 | if (selfpropcb) { |
1816 | WRITE_ONCE(fcs.stop, 0); | |
1817 | cur_ops->call(&fcs.rh, rcu_torture_fwd_prog_cb); | |
1818 | } | |
1819 | cver = READ_ONCE(rcu_torture_current_version); | |
1820 | gps = cur_ops->get_gp_seq(); | |
1821 | sd = cur_ops->stall_dur() + 1; | |
1822 | sd4 = (sd + fwd_progress_div - 1) / fwd_progress_div; | |
1823 | dur = sd4 + torture_random(&trs) % (sd - sd4); | |
6b1b8325 PM |
1824 | WRITE_ONCE(rfp->rcu_fwd_startat, jiffies); |
1825 | stopat = rfp->rcu_fwd_startat + dur; | |
e0aff973 | 1826 | while (time_before(jiffies, stopat) && |
60013d5d | 1827 | !shutdown_time_arrived() && |
e0aff973 | 1828 | !READ_ONCE(rcu_fwd_emergency_stop) && !torture_must_stop()) { |
6b3de7a1 PM |
1829 | idx = cur_ops->readlock(); |
1830 | udelay(10); | |
1831 | cur_ops->readunlock(idx); | |
1832 | if (!fwd_progress_need_resched || need_resched()) | |
fbbd5e35 | 1833 | cond_resched(); |
6b3de7a1 PM |
1834 | } |
1835 | (*tested_tries)++; | |
e0aff973 | 1836 | if (!time_before(jiffies, stopat) && |
60013d5d | 1837 | !shutdown_time_arrived() && |
e0aff973 | 1838 | !READ_ONCE(rcu_fwd_emergency_stop) && !torture_must_stop()) { |
6b3de7a1 PM |
1839 | (*tested)++; |
1840 | cver = READ_ONCE(rcu_torture_current_version) - cver; | |
1841 | gps = rcutorture_seq_diff(cur_ops->get_gp_seq(), gps); | |
1842 | WARN_ON(!cver && gps < 2); | |
1843 | pr_alert("%s: Duration %ld cver %ld gps %ld\n", __func__, dur, cver, gps); | |
1844 | } | |
1845 | if (selfpropcb) { | |
1846 | WRITE_ONCE(fcs.stop, 1); | |
1847 | cur_ops->sync(); /* Wait for running CB to complete. */ | |
1848 | cur_ops->cb_barrier(); /* Wait for queued callbacks. */ | |
1849 | } | |
1850 | ||
1851 | if (selfpropcb) { | |
1852 | WARN_ON(READ_ONCE(fcs.stop) != 2); | |
1853 | destroy_rcu_head_on_stack(&fcs.rh); | |
1854 | } | |
e8516c64 PM |
1855 | schedule_timeout_uninterruptible(HZ / 10); /* Let kthreads recover. */ |
1856 | WRITE_ONCE(rcu_fwd_cb_nodelay, false); | |
6b3de7a1 PM |
1857 | } |
1858 | ||
1859 | /* Carry out call_rcu() forward-progress testing. */ | |
6b1b8325 | 1860 | static void rcu_torture_fwd_prog_cr(struct rcu_fwd *rfp) |
6b3de7a1 PM |
1861 | { |
1862 | unsigned long cver; | |
79ba7ff5 | 1863 | unsigned long flags; |
6b3de7a1 PM |
1864 | unsigned long gps; |
1865 | int i; | |
48718485 PM |
1866 | long n_launders; |
1867 | long n_launders_cb_snap; | |
1868 | long n_launders_sa; | |
1869 | long n_max_cbs; | |
1870 | long n_max_gps; | |
1871 | struct rcu_fwd_cb *rfcp; | |
1872 | struct rcu_fwd_cb *rfcpn; | |
1b27291b | 1873 | unsigned long stopat; |
48718485 | 1874 | unsigned long stoppedat; |
6b3de7a1 | 1875 | |
2667ccce PM |
1876 | if (READ_ONCE(rcu_fwd_emergency_stop)) |
1877 | return; /* Get out of the way quickly, no GP wait! */ | |
c682db55 PM |
1878 | if (!cur_ops->call) |
1879 | return; /* Can't do call_rcu() fwd prog without ->call. */ | |
2667ccce | 1880 | |
6b3de7a1 PM |
1881 | /* Loop continuously posting RCU callbacks. */ |
1882 | WRITE_ONCE(rcu_fwd_cb_nodelay, true); | |
1883 | cur_ops->sync(); /* Later readers see above write. */ | |
6b1b8325 PM |
1884 | WRITE_ONCE(rfp->rcu_fwd_startat, jiffies); |
1885 | stopat = rfp->rcu_fwd_startat + MAX_FWD_CB_JIFFIES; | |
6b3de7a1 | 1886 | n_launders = 0; |
6b1b8325 | 1887 | rfp->n_launders_cb = 0; // Hoist initialization for multi-kthread |
6b3de7a1 PM |
1888 | n_launders_sa = 0; |
1889 | n_max_cbs = 0; | |
1890 | n_max_gps = 0; | |
6b1b8325 PM |
1891 | for (i = 0; i < ARRAY_SIZE(rfp->n_launders_hist); i++) |
1892 | rfp->n_launders_hist[i].n_launders = 0; | |
6b3de7a1 PM |
1893 | cver = READ_ONCE(rcu_torture_current_version); |
1894 | gps = cur_ops->get_gp_seq(); | |
6b1b8325 | 1895 | rfp->rcu_launder_gp_seq_start = gps; |
d38e6dc6 | 1896 | tick_dep_set_task(current, TICK_DEP_BIT_RCU); |
e0aff973 | 1897 | while (time_before(jiffies, stopat) && |
60013d5d | 1898 | !shutdown_time_arrived() && |
e0aff973 | 1899 | !READ_ONCE(rcu_fwd_emergency_stop) && !torture_must_stop()) { |
6b1b8325 | 1900 | rfcp = READ_ONCE(rfp->rcu_fwd_cb_head); |
6b3de7a1 PM |
1901 | rfcpn = NULL; |
1902 | if (rfcp) | |
1903 | rfcpn = READ_ONCE(rfcp->rfc_next); | |
1904 | if (rfcpn) { | |
1905 | if (rfcp->rfc_gps >= MIN_FWD_CB_LAUNDERS && | |
1906 | ++n_max_gps >= MIN_FWD_CBS_LAUNDERED) | |
1907 | break; | |
6b1b8325 | 1908 | rfp->rcu_fwd_cb_head = rfcpn; |
6b3de7a1 PM |
1909 | n_launders++; |
1910 | n_launders_sa++; | |
1911 | } else { | |
1912 | rfcp = kmalloc(sizeof(*rfcp), GFP_KERNEL); | |
1913 | if (WARN_ON_ONCE(!rfcp)) { | |
1914 | schedule_timeout_interruptible(1); | |
1915 | continue; | |
1916 | } | |
1917 | n_max_cbs++; | |
1918 | n_launders_sa = 0; | |
1919 | rfcp->rfc_gps = 0; | |
6b1b8325 | 1920 | rfcp->rfc_rfp = rfp; |
6b3de7a1 PM |
1921 | } |
1922 | cur_ops->call(&rfcp->rh, rcu_torture_fwd_cb_cr); | |
bd1bfc51 | 1923 | rcu_torture_fwd_prog_cond_resched(n_launders + n_max_cbs); |
79ba7ff5 PM |
1924 | if (tick_nohz_full_enabled()) { |
1925 | local_irq_save(flags); | |
1926 | rcu_momentary_dyntick_idle(); | |
1927 | local_irq_restore(flags); | |
1928 | } | |
6b3de7a1 PM |
1929 | } |
1930 | stoppedat = jiffies; | |
6b1b8325 | 1931 | n_launders_cb_snap = READ_ONCE(rfp->n_launders_cb); |
6b3de7a1 PM |
1932 | cver = READ_ONCE(rcu_torture_current_version) - cver; |
1933 | gps = rcutorture_seq_diff(cur_ops->get_gp_seq(), gps); | |
1934 | cur_ops->cb_barrier(); /* Wait for callbacks to be invoked. */ | |
6764100b | 1935 | (void)rcu_torture_fwd_prog_cbfree(rfp); |
2667ccce | 1936 | |
60013d5d PM |
1937 | if (!torture_must_stop() && !READ_ONCE(rcu_fwd_emergency_stop) && |
1938 | !shutdown_time_arrived()) { | |
6b3de7a1 PM |
1939 | WARN_ON(n_max_gps < MIN_FWD_CBS_LAUNDERED); |
1940 | pr_alert("%s Duration %lu barrier: %lu pending %ld n_launders: %ld n_launders_sa: %ld n_max_gps: %ld n_max_cbs: %ld cver %ld gps %ld\n", | |
1941 | __func__, | |
6b1b8325 | 1942 | stoppedat - rfp->rcu_fwd_startat, jiffies - stoppedat, |
6b3de7a1 PM |
1943 | n_launders + n_max_cbs - n_launders_cb_snap, |
1944 | n_launders, n_launders_sa, | |
1945 | n_max_gps, n_max_cbs, cver, gps); | |
6b1b8325 | 1946 | rcu_torture_fwd_cb_hist(rfp); |
6b3de7a1 | 1947 | } |
e8516c64 | 1948 | schedule_timeout_uninterruptible(HZ); /* Let CBs drain. */ |
d38e6dc6 | 1949 | tick_dep_clear_task(current, TICK_DEP_BIT_RCU); |
e8516c64 | 1950 | WRITE_ONCE(rcu_fwd_cb_nodelay, false); |
6b3de7a1 PM |
1951 | } |
1952 | ||
e0aff973 PM |
1953 | |
1954 | /* | |
1955 | * OOM notifier, but this only prints diagnostic information for the | |
1956 | * current forward-progress test. | |
1957 | */ | |
1958 | static int rcutorture_oom_notify(struct notifier_block *self, | |
1959 | unsigned long notused, void *nfreed) | |
1960 | { | |
5155be99 | 1961 | struct rcu_fwd *rfp = rcu_fwds; |
6764100b | 1962 | |
2667ccce PM |
1963 | WARN(1, "%s invoked upon OOM during forward-progress testing.\n", |
1964 | __func__); | |
6764100b PM |
1965 | rcu_torture_fwd_cb_hist(rfp); |
1966 | rcu_fwd_progress_check(1 + (jiffies - READ_ONCE(rfp->rcu_fwd_startat)) / 2); | |
e0aff973 | 1967 | WRITE_ONCE(rcu_fwd_emergency_stop, true); |
2667ccce PM |
1968 | smp_mb(); /* Emergency stop before free and wait to avoid hangs. */ |
1969 | pr_info("%s: Freed %lu RCU callbacks.\n", | |
6764100b | 1970 | __func__, rcu_torture_fwd_prog_cbfree(rfp)); |
2667ccce PM |
1971 | rcu_barrier(); |
1972 | pr_info("%s: Freed %lu RCU callbacks.\n", | |
6764100b | 1973 | __func__, rcu_torture_fwd_prog_cbfree(rfp)); |
2667ccce PM |
1974 | rcu_barrier(); |
1975 | pr_info("%s: Freed %lu RCU callbacks.\n", | |
6764100b | 1976 | __func__, rcu_torture_fwd_prog_cbfree(rfp)); |
2667ccce PM |
1977 | smp_mb(); /* Frees before return to avoid redoing OOM. */ |
1978 | (*(unsigned long *)nfreed)++; /* Forward progress CBs freed! */ | |
1979 | pr_info("%s returning after OOM processing.\n", __func__); | |
e0aff973 PM |
1980 | return NOTIFY_OK; |
1981 | } | |
1982 | ||
1983 | static struct notifier_block rcutorture_oom_nb = { | |
1984 | .notifier_call = rcutorture_oom_notify | |
1985 | }; | |
1986 | ||
6b3de7a1 PM |
1987 | /* Carry out grace-period forward-progress testing. */ |
1988 | static int rcu_torture_fwd_prog(void *args) | |
1989 | { | |
6b1b8325 | 1990 | struct rcu_fwd *rfp = args; |
f4de46ed | 1991 | int tested = 0; |
152f4afb | 1992 | int tested_tries = 0; |
1b27291b PM |
1993 | |
1994 | VERBOSE_TOROUT_STRING("rcu_torture_fwd_progress task started"); | |
5ab7ab83 | 1995 | rcu_bind_current_to_nocb(); |
fecad509 PM |
1996 | if (!IS_ENABLED(CONFIG_SMP) || !IS_ENABLED(CONFIG_RCU_BOOST)) |
1997 | set_user_nice(current, MAX_NICE); | |
1b27291b PM |
1998 | do { |
1999 | schedule_timeout_interruptible(fwd_progress_holdoff * HZ); | |
e0aff973 PM |
2000 | WRITE_ONCE(rcu_fwd_emergency_stop, false); |
2001 | register_oom_notifier(&rcutorture_oom_nb); | |
43550809 PM |
2002 | if (!IS_ENABLED(CONFIG_TINY_RCU) || |
2003 | rcu_inkernel_boot_has_ended()) | |
2004 | rcu_torture_fwd_prog_nr(rfp, &tested, &tested_tries); | |
2005 | if (rcu_inkernel_boot_has_ended()) | |
2006 | rcu_torture_fwd_prog_cr(rfp); | |
e0aff973 | 2007 | unregister_oom_notifier(&rcutorture_oom_nb); |
48718485 | 2008 | |
1b27291b PM |
2009 | /* Avoid slow periods, better to test when busy. */ |
2010 | stutter_wait("rcu_torture_fwd_prog"); | |
2011 | } while (!torture_must_stop()); | |
152f4afb PM |
2012 | /* Short runs might not contain a valid forward-progress attempt. */ |
2013 | WARN_ON(!tested && tested_tries >= 5); | |
f4de46ed | 2014 | pr_alert("%s: tested %d tested_tries %d\n", __func__, tested, tested_tries); |
1b27291b PM |
2015 | torture_kthread_stopping("rcu_torture_fwd_prog"); |
2016 | return 0; | |
2017 | } | |
2018 | ||
2019 | /* If forward-progress checking is requested and feasible, spawn the thread. */ | |
2020 | static int __init rcu_torture_fwd_prog_init(void) | |
2021 | { | |
5155be99 | 2022 | struct rcu_fwd *rfp; |
6764100b | 2023 | |
1b27291b PM |
2024 | if (!fwd_progress) |
2025 | return 0; /* Not requested, so don't do it. */ | |
5ac7cdc2 PM |
2026 | if (!cur_ops->stall_dur || cur_ops->stall_dur() <= 0 || |
2027 | cur_ops == &rcu_busted_ops) { | |
1b27291b PM |
2028 | VERBOSE_TOROUT_STRING("rcu_torture_fwd_prog_init: Disabled, unsupported by RCU flavor under test"); |
2029 | return 0; | |
2030 | } | |
2031 | if (stall_cpu > 0) { | |
2032 | VERBOSE_TOROUT_STRING("rcu_torture_fwd_prog_init: Disabled, conflicts with CPU-stall testing"); | |
2033 | if (IS_MODULE(CONFIG_RCU_TORTURE_TESTS)) | |
2034 | return -EINVAL; /* In module, can fail back to user. */ | |
2035 | WARN_ON(1); /* Make sure rcutorture notices conflict. */ | |
2036 | return 0; | |
2037 | } | |
2038 | if (fwd_progress_holdoff <= 0) | |
2039 | fwd_progress_holdoff = 1; | |
2040 | if (fwd_progress_div <= 0) | |
2041 | fwd_progress_div = 4; | |
5155be99 PM |
2042 | rfp = kzalloc(sizeof(*rfp), GFP_KERNEL); |
2043 | if (!rfp) | |
2044 | return -ENOMEM; | |
2045 | spin_lock_init(&rfp->rcu_fwd_lock); | |
2046 | rfp->rcu_fwd_cb_tail = &rfp->rcu_fwd_cb_head; | |
6764100b | 2047 | return torture_create_kthread(rcu_torture_fwd_prog, rfp, fwd_prog_task); |
1b27291b PM |
2048 | } |
2049 | ||
fae4b54f | 2050 | /* Callback function for RCU barrier testing. */ |
b3b8a4d4 | 2051 | static void rcu_torture_barrier_cbf(struct rcu_head *rcu) |
fae4b54f PM |
2052 | { |
2053 | atomic_inc(&barrier_cbs_invoked); | |
2054 | } | |
2055 | ||
50d4b629 PM |
2056 | /* IPI handler to get callback posted on desired CPU, if online. */ |
2057 | static void rcu_torture_barrier1cb(void *rcu_void) | |
2058 | { | |
2059 | struct rcu_head *rhp = rcu_void; | |
2060 | ||
2061 | cur_ops->call(rhp, rcu_torture_barrier_cbf); | |
2062 | } | |
2063 | ||
fae4b54f PM |
2064 | /* kthread function to register callbacks used to test RCU barriers. */ |
2065 | static int rcu_torture_barrier_cbs(void *arg) | |
2066 | { | |
2067 | long myid = (long)arg; | |
c6ebcbb6 | 2068 | bool lastphase = 0; |
78e4bc34 | 2069 | bool newphase; |
fae4b54f PM |
2070 | struct rcu_head rcu; |
2071 | ||
2072 | init_rcu_head_on_stack(&rcu); | |
5ccf60f2 | 2073 | VERBOSE_TOROUT_STRING("rcu_torture_barrier_cbs task started"); |
d277d868 | 2074 | set_user_nice(current, MAX_NICE); |
fae4b54f PM |
2075 | do { |
2076 | wait_event(barrier_cbs_wq[myid], | |
78e4bc34 | 2077 | (newphase = |
6c7ed42c | 2078 | smp_load_acquire(&barrier_phase)) != lastphase || |
36970bb9 | 2079 | torture_must_stop()); |
78e4bc34 | 2080 | lastphase = newphase; |
36970bb9 | 2081 | if (torture_must_stop()) |
fae4b54f | 2082 | break; |
6c7ed42c PM |
2083 | /* |
2084 | * The above smp_load_acquire() ensures barrier_phase load | |
aab05738 | 2085 | * is ordered before the following ->call(). |
6c7ed42c | 2086 | */ |
50d4b629 PM |
2087 | if (smp_call_function_single(myid, rcu_torture_barrier1cb, |
2088 | &rcu, 1)) { | |
2089 | // IPI failed, so use direct call from current CPU. | |
2090 | cur_ops->call(&rcu, rcu_torture_barrier_cbf); | |
2091 | } | |
fae4b54f PM |
2092 | if (atomic_dec_and_test(&barrier_cbs_count)) |
2093 | wake_up(&barrier_wq); | |
36970bb9 | 2094 | } while (!torture_must_stop()); |
69c60455 PM |
2095 | if (cur_ops->cb_barrier != NULL) |
2096 | cur_ops->cb_barrier(); | |
fae4b54f | 2097 | destroy_rcu_head_on_stack(&rcu); |
7fafaac5 | 2098 | torture_kthread_stopping("rcu_torture_barrier_cbs"); |
fae4b54f PM |
2099 | return 0; |
2100 | } | |
2101 | ||
2102 | /* kthread function to drive and coordinate RCU barrier testing. */ | |
2103 | static int rcu_torture_barrier(void *arg) | |
2104 | { | |
2105 | int i; | |
2106 | ||
5ccf60f2 | 2107 | VERBOSE_TOROUT_STRING("rcu_torture_barrier task starting"); |
fae4b54f PM |
2108 | do { |
2109 | atomic_set(&barrier_cbs_invoked, 0); | |
2110 | atomic_set(&barrier_cbs_count, n_barrier_cbs); | |
6c7ed42c PM |
2111 | /* Ensure barrier_phase ordered after prior assignments. */ |
2112 | smp_store_release(&barrier_phase, !barrier_phase); | |
fae4b54f PM |
2113 | for (i = 0; i < n_barrier_cbs; i++) |
2114 | wake_up(&barrier_cbs_wq[i]); | |
2115 | wait_event(barrier_wq, | |
2116 | atomic_read(&barrier_cbs_count) == 0 || | |
36970bb9 PM |
2117 | torture_must_stop()); |
2118 | if (torture_must_stop()) | |
fae4b54f PM |
2119 | break; |
2120 | n_barrier_attempts++; | |
78e4bc34 | 2121 | cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */ |
fae4b54f PM |
2122 | if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { |
2123 | n_rcu_torture_barrier_error++; | |
7602de4a PM |
2124 | pr_err("barrier_cbs_invoked = %d, n_barrier_cbs = %d\n", |
2125 | atomic_read(&barrier_cbs_invoked), | |
2126 | n_barrier_cbs); | |
9470a18f PM |
2127 | WARN_ON(1); |
2128 | // Wait manually for the remaining callbacks | |
2129 | i = 0; | |
2130 | do { | |
2131 | if (WARN_ON(i++ > HZ)) | |
2132 | i = INT_MIN; | |
2133 | schedule_timeout_interruptible(1); | |
2134 | cur_ops->cb_barrier(); | |
2135 | } while (atomic_read(&barrier_cbs_invoked) != | |
2136 | n_barrier_cbs && | |
2137 | !torture_must_stop()); | |
2138 | smp_mb(); // Can't trust ordering if broken. | |
2139 | if (!torture_must_stop()) | |
2140 | pr_err("Recovered: barrier_cbs_invoked = %d\n", | |
2141 | atomic_read(&barrier_cbs_invoked)); | |
bf5b6435 JFG |
2142 | } else { |
2143 | n_barrier_successes++; | |
fae4b54f | 2144 | } |
fae4b54f | 2145 | schedule_timeout_interruptible(HZ / 10); |
36970bb9 | 2146 | } while (!torture_must_stop()); |
7fafaac5 | 2147 | torture_kthread_stopping("rcu_torture_barrier"); |
fae4b54f PM |
2148 | return 0; |
2149 | } | |
2150 | ||
2151 | /* Initialize RCU barrier testing. */ | |
2152 | static int rcu_torture_barrier_init(void) | |
2153 | { | |
2154 | int i; | |
2155 | int ret; | |
2156 | ||
d9eba768 | 2157 | if (n_barrier_cbs <= 0) |
fae4b54f PM |
2158 | return 0; |
2159 | if (cur_ops->call == NULL || cur_ops->cb_barrier == NULL) { | |
2caa1e44 PM |
2160 | pr_alert("%s" TORTURE_FLAG |
2161 | " Call or barrier ops missing for %s,\n", | |
2162 | torture_type, cur_ops->name); | |
2163 | pr_alert("%s" TORTURE_FLAG | |
2164 | " RCU barrier testing omitted from run.\n", | |
2165 | torture_type); | |
fae4b54f PM |
2166 | return 0; |
2167 | } | |
2168 | atomic_set(&barrier_cbs_count, 0); | |
2169 | atomic_set(&barrier_cbs_invoked, 0); | |
2170 | barrier_cbs_tasks = | |
68a675d4 | 2171 | kcalloc(n_barrier_cbs, sizeof(barrier_cbs_tasks[0]), |
fae4b54f PM |
2172 | GFP_KERNEL); |
2173 | barrier_cbs_wq = | |
68a675d4 | 2174 | kcalloc(n_barrier_cbs, sizeof(barrier_cbs_wq[0]), GFP_KERNEL); |
de5e6437 | 2175 | if (barrier_cbs_tasks == NULL || !barrier_cbs_wq) |
fae4b54f PM |
2176 | return -ENOMEM; |
2177 | for (i = 0; i < n_barrier_cbs; i++) { | |
2178 | init_waitqueue_head(&barrier_cbs_wq[i]); | |
47cf29b9 PM |
2179 | ret = torture_create_kthread(rcu_torture_barrier_cbs, |
2180 | (void *)(long)i, | |
2181 | barrier_cbs_tasks[i]); | |
2182 | if (ret) | |
fae4b54f | 2183 | return ret; |
fae4b54f | 2184 | } |
47cf29b9 | 2185 | return torture_create_kthread(rcu_torture_barrier, NULL, barrier_task); |
fae4b54f PM |
2186 | } |
2187 | ||
2188 | /* Clean up after RCU barrier testing. */ | |
2189 | static void rcu_torture_barrier_cleanup(void) | |
2190 | { | |
2191 | int i; | |
2192 | ||
9c029b86 | 2193 | torture_stop_kthread(rcu_torture_barrier, barrier_task); |
fae4b54f | 2194 | if (barrier_cbs_tasks != NULL) { |
9c029b86 PM |
2195 | for (i = 0; i < n_barrier_cbs; i++) |
2196 | torture_stop_kthread(rcu_torture_barrier_cbs, | |
2197 | barrier_cbs_tasks[i]); | |
fae4b54f PM |
2198 | kfree(barrier_cbs_tasks); |
2199 | barrier_cbs_tasks = NULL; | |
2200 | } | |
2201 | if (barrier_cbs_wq != NULL) { | |
2202 | kfree(barrier_cbs_wq); | |
2203 | barrier_cbs_wq = NULL; | |
2204 | } | |
2205 | } | |
2206 | ||
4babd855 JFG |
2207 | static bool rcu_torture_can_boost(void) |
2208 | { | |
2209 | static int boost_warn_once; | |
2210 | int prio; | |
2211 | ||
2212 | if (!(test_boost == 1 && cur_ops->can_boost) && test_boost != 2) | |
2213 | return false; | |
2214 | ||
2215 | prio = rcu_get_gp_kthreads_prio(); | |
2216 | if (!prio) | |
2217 | return false; | |
2218 | ||
2219 | if (prio < 2) { | |
2220 | if (boost_warn_once == 1) | |
2221 | return false; | |
2222 | ||
bf5b6435 | 2223 | pr_alert("%s: WARN: RCU kthread priority too low to test boosting. Skipping RCU boost test. Try passing rcutree.kthread_prio > 1 on the kernel command line.\n", KBUILD_MODNAME); |
4babd855 JFG |
2224 | boost_warn_once = 1; |
2225 | return false; | |
2226 | } | |
2227 | ||
2228 | return true; | |
2229 | } | |
2230 | ||
0ffd374b | 2231 | static enum cpuhp_state rcutor_hp; |
8e8be45e | 2232 | |
a241ec65 PM |
2233 | static void |
2234 | rcu_torture_cleanup(void) | |
2235 | { | |
c116dba6 | 2236 | int firsttime; |
034777d7 | 2237 | int flags = 0; |
aebc8264 | 2238 | unsigned long gp_seq = 0; |
a241ec65 PM |
2239 | int i; |
2240 | ||
d36a7a0d | 2241 | if (torture_cleanup_begin()) { |
343e9099 PM |
2242 | if (cur_ops->cb_barrier != NULL) |
2243 | cur_ops->cb_barrier(); | |
2244 | return; | |
2245 | } | |
b813afae PM |
2246 | if (!cur_ops) { |
2247 | torture_cleanup_end(); | |
2248 | return; | |
2249 | } | |
d84f5203 | 2250 | |
f7a81b12 | 2251 | show_rcu_gp_kthreads(); |
fae4b54f | 2252 | rcu_torture_barrier_cleanup(); |
1b27291b | 2253 | torture_stop_kthread(rcu_torture_fwd_prog, fwd_prog_task); |
9c029b86 | 2254 | torture_stop_kthread(rcu_torture_stall, stall_task); |
9c029b86 | 2255 | torture_stop_kthread(rcu_torture_writer, writer_task); |
a241ec65 | 2256 | |
c8e5b163 | 2257 | if (reader_tasks) { |
9c029b86 PM |
2258 | for (i = 0; i < nrealreaders; i++) |
2259 | torture_stop_kthread(rcu_torture_reader, | |
2260 | reader_tasks[i]); | |
a241ec65 | 2261 | kfree(reader_tasks); |
a241ec65 PM |
2262 | } |
2263 | rcu_torture_current = NULL; | |
2264 | ||
c8e5b163 | 2265 | if (fakewriter_tasks) { |
b772e1dd | 2266 | for (i = 0; i < nfakewriters; i++) { |
9c029b86 PM |
2267 | torture_stop_kthread(rcu_torture_fakewriter, |
2268 | fakewriter_tasks[i]); | |
b772e1dd JT |
2269 | } |
2270 | kfree(fakewriter_tasks); | |
2271 | fakewriter_tasks = NULL; | |
2272 | } | |
2273 | ||
aebc8264 PM |
2274 | rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq); |
2275 | srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq); | |
2276 | pr_alert("%s: End-test grace-period state: g%lu f%#x\n", | |
2277 | cur_ops->name, gp_seq, flags); | |
9c029b86 PM |
2278 | torture_stop_kthread(rcu_torture_stats, stats_task); |
2279 | torture_stop_kthread(rcu_torture_fqs, fqs_task); | |
4babd855 | 2280 | if (rcu_torture_can_boost()) |
0ffd374b | 2281 | cpuhp_remove_state(rcutor_hp); |
bf66f18e | 2282 | |
ca1d51ed | 2283 | /* |
62a1a945 | 2284 | * Wait for all RCU callbacks to fire, then do torture-type-specific |
ca1d51ed PM |
2285 | * cleanup operations. |
2286 | */ | |
2326974d PM |
2287 | if (cur_ops->cb_barrier != NULL) |
2288 | cur_ops->cb_barrier(); | |
ca1d51ed PM |
2289 | if (cur_ops->cleanup != NULL) |
2290 | cur_ops->cleanup(); | |
a241ec65 | 2291 | |
a241ec65 | 2292 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
72e9bb54 | 2293 | |
c116dba6 PM |
2294 | if (err_segs_recorded) { |
2295 | pr_alert("Failure/close-call rcutorture reader segments:\n"); | |
2296 | if (rt_read_nsegs == 0) | |
2297 | pr_alert("\t: No segments recorded!!!\n"); | |
2298 | firsttime = 1; | |
2299 | for (i = 0; i < rt_read_nsegs; i++) { | |
2300 | pr_alert("\t%d: %#x ", i, err_segs[i].rt_readstate); | |
2301 | if (err_segs[i].rt_delay_jiffies != 0) { | |
2302 | pr_cont("%s%ldjiffies", firsttime ? "" : "+", | |
2303 | err_segs[i].rt_delay_jiffies); | |
2304 | firsttime = 0; | |
2305 | } | |
2306 | if (err_segs[i].rt_delay_ms != 0) { | |
2307 | pr_cont("%s%ldms", firsttime ? "" : "+", | |
2308 | err_segs[i].rt_delay_ms); | |
2309 | firsttime = 0; | |
2310 | } | |
2311 | if (err_segs[i].rt_delay_us != 0) { | |
2312 | pr_cont("%s%ldus", firsttime ? "" : "+", | |
2313 | err_segs[i].rt_delay_us); | |
2314 | firsttime = 0; | |
2315 | } | |
2316 | pr_cont("%s\n", | |
2317 | err_segs[i].rt_preempted ? "preempted" : ""); | |
2318 | ||
2319 | } | |
2320 | } | |
fae4b54f | 2321 | if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error) |
8e8be45e | 2322 | rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); |
2e9e8081 | 2323 | else if (torture_onoff_failures()) |
091541bb PM |
2324 | rcu_torture_print_module_parms(cur_ops, |
2325 | "End of test: RCU_HOTPLUG"); | |
95c38322 | 2326 | else |
8e8be45e | 2327 | rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); |
d36a7a0d | 2328 | torture_cleanup_end(); |
a241ec65 PM |
2329 | } |
2330 | ||
d2818df1 PM |
2331 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD |
2332 | static void rcu_torture_leak_cb(struct rcu_head *rhp) | |
2333 | { | |
2334 | } | |
2335 | ||
2336 | static void rcu_torture_err_cb(struct rcu_head *rhp) | |
2337 | { | |
2338 | /* | |
2339 | * This -might- happen due to race conditions, but is unlikely. | |
2340 | * The scenario that leads to this happening is that the | |
2341 | * first of the pair of duplicate callbacks is queued, | |
2342 | * someone else starts a grace period that includes that | |
2343 | * callback, then the second of the pair must wait for the | |
2344 | * next grace period. Unlikely, but can happen. If it | |
2345 | * does happen, the debug-objects subsystem won't have splatted. | |
2346 | */ | |
e0d31a34 | 2347 | pr_alert("%s: duplicated callback was invoked.\n", KBUILD_MODNAME); |
d2818df1 PM |
2348 | } |
2349 | #endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
2350 | ||
2351 | /* | |
2352 | * Verify that double-free causes debug-objects to complain, but only | |
2353 | * if CONFIG_DEBUG_OBJECTS_RCU_HEAD=y. Otherwise, say that the test | |
2354 | * cannot be carried out. | |
2355 | */ | |
2356 | static void rcu_test_debug_objects(void) | |
2357 | { | |
2358 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD | |
2359 | struct rcu_head rh1; | |
2360 | struct rcu_head rh2; | |
2361 | ||
2362 | init_rcu_head_on_stack(&rh1); | |
2363 | init_rcu_head_on_stack(&rh2); | |
e0d31a34 | 2364 | pr_alert("%s: WARN: Duplicate call_rcu() test starting.\n", KBUILD_MODNAME); |
d2818df1 PM |
2365 | |
2366 | /* Try to queue the rh2 pair of callbacks for the same grace period. */ | |
2367 | preempt_disable(); /* Prevent preemption from interrupting test. */ | |
2368 | rcu_read_lock(); /* Make it impossible to finish a grace period. */ | |
2369 | call_rcu(&rh1, rcu_torture_leak_cb); /* Start grace period. */ | |
2370 | local_irq_disable(); /* Make it harder to start a new grace period. */ | |
2371 | call_rcu(&rh2, rcu_torture_leak_cb); | |
2372 | call_rcu(&rh2, rcu_torture_err_cb); /* Duplicate callback. */ | |
2373 | local_irq_enable(); | |
2374 | rcu_read_unlock(); | |
2375 | preempt_enable(); | |
2376 | ||
2377 | /* Wait for them all to get done so we can safely return. */ | |
2378 | rcu_barrier(); | |
e0d31a34 | 2379 | pr_alert("%s: WARN: Duplicate call_rcu() test complete.\n", KBUILD_MODNAME); |
d2818df1 PM |
2380 | destroy_rcu_head_on_stack(&rh1); |
2381 | destroy_rcu_head_on_stack(&rh2); | |
2382 | #else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
e0d31a34 | 2383 | pr_alert("%s: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n", KBUILD_MODNAME); |
d2818df1 PM |
2384 | #endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ |
2385 | } | |
2386 | ||
3a6cb58f PM |
2387 | static void rcutorture_sync(void) |
2388 | { | |
2389 | static unsigned long n; | |
2390 | ||
2391 | if (cur_ops->sync && !(++n & 0xfff)) | |
2392 | cur_ops->sync(); | |
2393 | } | |
2394 | ||
6f8bc500 | 2395 | static int __init |
a241ec65 PM |
2396 | rcu_torture_init(void) |
2397 | { | |
c04dd09b | 2398 | long i; |
a241ec65 PM |
2399 | int cpu; |
2400 | int firsterr = 0; | |
2ec1f2d9 | 2401 | static struct rcu_torture_ops *torture_ops[] = { |
c770c82a | 2402 | &rcu_ops, &rcu_busted_ops, &srcu_ops, &srcud_ops, |
c682db55 | 2403 | &busted_srcud_ops, &tasks_ops, &trivial_ops, |
2ec1f2d9 | 2404 | }; |
a241ec65 | 2405 | |
a2f2577d | 2406 | if (!torture_init_begin(torture_type, verbose)) |
5228084e | 2407 | return -EBUSY; |
343e9099 | 2408 | |
a241ec65 | 2409 | /* Process args and tell the world that the torturer is on the job. */ |
ade5fb81 | 2410 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
72e9bb54 | 2411 | cur_ops = torture_ops[i]; |
ade5fb81 | 2412 | if (strcmp(torture_type, cur_ops->name) == 0) |
72e9bb54 | 2413 | break; |
72e9bb54 | 2414 | } |
ade5fb81 | 2415 | if (i == ARRAY_SIZE(torture_ops)) { |
2caa1e44 PM |
2416 | pr_alert("rcu-torture: invalid torture type: \"%s\"\n", |
2417 | torture_type); | |
2418 | pr_alert("rcu-torture types:"); | |
cf886c44 | 2419 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) |
a7538352 JP |
2420 | pr_cont(" %s", torture_ops[i]->name); |
2421 | pr_cont("\n"); | |
e746b558 | 2422 | WARN_ON(!IS_MODULE(CONFIG_RCU_TORTURE_TEST)); |
889d487a | 2423 | firsterr = -EINVAL; |
b813afae | 2424 | cur_ops = NULL; |
889d487a | 2425 | goto unwind; |
72e9bb54 | 2426 | } |
bf66f18e | 2427 | if (cur_ops->fqs == NULL && fqs_duration != 0) { |
2caa1e44 | 2428 | pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); |
bf66f18e PM |
2429 | fqs_duration = 0; |
2430 | } | |
c8e5b163 | 2431 | if (cur_ops->init) |
889d487a | 2432 | cur_ops->init(); |
72e9bb54 | 2433 | |
64e4b43a | 2434 | if (nreaders >= 0) { |
a241ec65 | 2435 | nrealreaders = nreaders; |
64e4b43a | 2436 | } else { |
3838cc18 | 2437 | nrealreaders = num_online_cpus() - 2 - nreaders; |
64e4b43a PM |
2438 | if (nrealreaders <= 0) |
2439 | nrealreaders = 1; | |
2440 | } | |
8e8be45e | 2441 | rcu_torture_print_module_parms(cur_ops, "Start of test"); |
a241ec65 PM |
2442 | |
2443 | /* Set up the freelist. */ | |
2444 | ||
2445 | INIT_LIST_HEAD(&rcu_torture_freelist); | |
788e770e | 2446 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
996417d2 | 2447 | rcu_tortures[i].rtort_mbtest = 0; |
a241ec65 PM |
2448 | list_add_tail(&rcu_tortures[i].rtort_free, |
2449 | &rcu_torture_freelist); | |
2450 | } | |
2451 | ||
2452 | /* Initialize the statistics so that each run gets its own numbers. */ | |
2453 | ||
2454 | rcu_torture_current = NULL; | |
2455 | rcu_torture_current_version = 0; | |
2456 | atomic_set(&n_rcu_torture_alloc, 0); | |
2457 | atomic_set(&n_rcu_torture_alloc_fail, 0); | |
2458 | atomic_set(&n_rcu_torture_free, 0); | |
996417d2 PM |
2459 | atomic_set(&n_rcu_torture_mberror, 0); |
2460 | atomic_set(&n_rcu_torture_error, 0); | |
fae4b54f | 2461 | n_rcu_torture_barrier_error = 0; |
8e8be45e PM |
2462 | n_rcu_torture_boost_ktrerror = 0; |
2463 | n_rcu_torture_boost_rterror = 0; | |
8e8be45e PM |
2464 | n_rcu_torture_boost_failure = 0; |
2465 | n_rcu_torture_boosts = 0; | |
a241ec65 PM |
2466 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
2467 | atomic_set(&rcu_torture_wcount[i], 0); | |
0a945022 | 2468 | for_each_possible_cpu(cpu) { |
a241ec65 PM |
2469 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
2470 | per_cpu(rcu_torture_count, cpu)[i] = 0; | |
2471 | per_cpu(rcu_torture_batch, cpu)[i] = 0; | |
2472 | } | |
2473 | } | |
c116dba6 PM |
2474 | err_segs_recorded = 0; |
2475 | rt_read_nsegs = 0; | |
a241ec65 PM |
2476 | |
2477 | /* Start up the kthreads. */ | |
2478 | ||
47cf29b9 PM |
2479 | firsterr = torture_create_kthread(rcu_torture_writer, NULL, |
2480 | writer_task); | |
2481 | if (firsterr) | |
a241ec65 | 2482 | goto unwind; |
4444d852 | 2483 | if (nfakewriters > 0) { |
68a675d4 | 2484 | fakewriter_tasks = kcalloc(nfakewriters, |
4444d852 PM |
2485 | sizeof(fakewriter_tasks[0]), |
2486 | GFP_KERNEL); | |
2487 | if (fakewriter_tasks == NULL) { | |
2488 | VERBOSE_TOROUT_ERRSTRING("out of memory"); | |
2489 | firsterr = -ENOMEM; | |
2490 | goto unwind; | |
2491 | } | |
b772e1dd JT |
2492 | } |
2493 | for (i = 0; i < nfakewriters; i++) { | |
47cf29b9 PM |
2494 | firsterr = torture_create_kthread(rcu_torture_fakewriter, |
2495 | NULL, fakewriter_tasks[i]); | |
2496 | if (firsterr) | |
b772e1dd | 2497 | goto unwind; |
b772e1dd | 2498 | } |
68a675d4 | 2499 | reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]), |
a241ec65 PM |
2500 | GFP_KERNEL); |
2501 | if (reader_tasks == NULL) { | |
5ccf60f2 | 2502 | VERBOSE_TOROUT_ERRSTRING("out of memory"); |
a241ec65 PM |
2503 | firsterr = -ENOMEM; |
2504 | goto unwind; | |
2505 | } | |
2506 | for (i = 0; i < nrealreaders; i++) { | |
c04dd09b | 2507 | firsterr = torture_create_kthread(rcu_torture_reader, (void *)i, |
47cf29b9 PM |
2508 | reader_tasks[i]); |
2509 | if (firsterr) | |
a241ec65 | 2510 | goto unwind; |
a241ec65 PM |
2511 | } |
2512 | if (stat_interval > 0) { | |
47cf29b9 PM |
2513 | firsterr = torture_create_kthread(rcu_torture_stats, NULL, |
2514 | stats_task); | |
2515 | if (firsterr) | |
a241ec65 | 2516 | goto unwind; |
a241ec65 | 2517 | } |
e8e255f7 | 2518 | if (test_no_idle_hz && shuffle_interval > 0) { |
3808dc9f PM |
2519 | firsterr = torture_shuffle_init(shuffle_interval * HZ); |
2520 | if (firsterr) | |
d84f5203 | 2521 | goto unwind; |
d84f5203 | 2522 | } |
d120f65f PM |
2523 | if (stutter < 0) |
2524 | stutter = 0; | |
2525 | if (stutter) { | |
ff3bf92d PM |
2526 | int t; |
2527 | ||
2528 | t = cur_ops->stall_dur ? cur_ops->stall_dur() : stutter * HZ; | |
2529 | firsterr = torture_stutter_init(stutter * HZ, t); | |
628edaa5 | 2530 | if (firsterr) |
d120f65f | 2531 | goto unwind; |
d120f65f | 2532 | } |
bf66f18e PM |
2533 | if (fqs_duration < 0) |
2534 | fqs_duration = 0; | |
2535 | if (fqs_duration) { | |
628edaa5 | 2536 | /* Create the fqs thread */ |
d0d0606e PM |
2537 | firsterr = torture_create_kthread(rcu_torture_fqs, NULL, |
2538 | fqs_task); | |
47cf29b9 | 2539 | if (firsterr) |
bf66f18e | 2540 | goto unwind; |
bf66f18e | 2541 | } |
8e8be45e PM |
2542 | if (test_boost_interval < 1) |
2543 | test_boost_interval = 1; | |
2544 | if (test_boost_duration < 2) | |
2545 | test_boost_duration = 2; | |
4babd855 | 2546 | if (rcu_torture_can_boost()) { |
8e8be45e PM |
2547 | |
2548 | boost_starttime = jiffies + test_boost_interval * HZ; | |
0ffd374b SAS |
2549 | |
2550 | firsterr = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "RCU_TORTURE", | |
2551 | rcutorture_booster_init, | |
2552 | rcutorture_booster_cleanup); | |
2553 | if (firsterr < 0) | |
2554 | goto unwind; | |
2555 | rcutor_hp = firsterr; | |
8e8be45e | 2556 | } |
60013d5d | 2557 | shutdown_jiffies = jiffies + shutdown_secs * HZ; |
01025ebc PM |
2558 | firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup); |
2559 | if (firsterr) | |
37e377d2 | 2560 | goto unwind; |
3a6cb58f PM |
2561 | firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval, |
2562 | rcutorture_sync); | |
01025ebc | 2563 | if (firsterr) |
37e377d2 | 2564 | goto unwind; |
01025ebc | 2565 | firsterr = rcu_torture_stall_init(); |
1b27291b PM |
2566 | if (firsterr) |
2567 | goto unwind; | |
2568 | firsterr = rcu_torture_fwd_prog_init(); | |
01025ebc | 2569 | if (firsterr) |
37e377d2 | 2570 | goto unwind; |
01025ebc PM |
2571 | firsterr = rcu_torture_barrier_init(); |
2572 | if (firsterr) | |
fae4b54f | 2573 | goto unwind; |
d2818df1 PM |
2574 | if (object_debug) |
2575 | rcu_test_debug_objects(); | |
b5daa8f3 | 2576 | torture_init_end(); |
a241ec65 PM |
2577 | return 0; |
2578 | ||
2579 | unwind: | |
b5daa8f3 | 2580 | torture_init_end(); |
a241ec65 PM |
2581 | rcu_torture_cleanup(); |
2582 | return firsterr; | |
2583 | } | |
2584 | ||
2585 | module_init(rcu_torture_init); | |
2586 | module_exit(rcu_torture_cleanup); |