1 // SPDX-License-Identifier: GPL-2.0+ 1 // SPDX-License-Identifier: GPL-2.0+
2 /* 2 /*
3 * Common functions for in-kernel torture test 3 * Common functions for in-kernel torture tests.
4 * 4 *
5 * Copyright (C) IBM Corporation, 2014 5 * Copyright (C) IBM Corporation, 2014
6 * 6 *
7 * Author: Paul E. McKenney <paulmck@linux.ibm 7 * Author: Paul E. McKenney <paulmck@linux.ibm.com>
8 * Based on kernel/rcu/torture.c. 8 * Based on kernel/rcu/torture.c.
9 */ 9 */
10 10
11 #define pr_fmt(fmt) fmt 11 #define pr_fmt(fmt) fmt
12 12
13 #include <linux/types.h> 13 #include <linux/types.h>
14 #include <linux/kernel.h> 14 #include <linux/kernel.h>
15 #include <linux/init.h> 15 #include <linux/init.h>
16 #include <linux/module.h> 16 #include <linux/module.h>
17 #include <linux/kthread.h> 17 #include <linux/kthread.h>
18 #include <linux/err.h> 18 #include <linux/err.h>
19 #include <linux/spinlock.h> 19 #include <linux/spinlock.h>
20 #include <linux/smp.h> 20 #include <linux/smp.h>
21 #include <linux/interrupt.h> 21 #include <linux/interrupt.h>
22 #include <linux/sched.h> 22 #include <linux/sched.h>
23 #include <linux/sched/clock.h> 23 #include <linux/sched/clock.h>
24 #include <linux/atomic.h> 24 #include <linux/atomic.h>
25 #include <linux/bitops.h> 25 #include <linux/bitops.h>
26 #include <linux/completion.h> 26 #include <linux/completion.h>
27 #include <linux/moduleparam.h> 27 #include <linux/moduleparam.h>
28 #include <linux/percpu.h> 28 #include <linux/percpu.h>
29 #include <linux/notifier.h> 29 #include <linux/notifier.h>
30 #include <linux/reboot.h> 30 #include <linux/reboot.h>
31 #include <linux/freezer.h> 31 #include <linux/freezer.h>
32 #include <linux/cpu.h> 32 #include <linux/cpu.h>
33 #include <linux/delay.h> 33 #include <linux/delay.h>
34 #include <linux/stat.h> 34 #include <linux/stat.h>
35 #include <linux/slab.h> 35 #include <linux/slab.h>
36 #include <linux/trace_clock.h> 36 #include <linux/trace_clock.h>
37 #include <linux/ktime.h> 37 #include <linux/ktime.h>
38 #include <asm/byteorder.h> 38 #include <asm/byteorder.h>
39 #include <linux/torture.h> 39 #include <linux/torture.h>
40 #include <linux/sched/rt.h> <<
41 #include "rcu/rcu.h" 40 #include "rcu/rcu.h"
42 41
43 MODULE_DESCRIPTION("Common functions for in-ke <<
44 MODULE_LICENSE("GPL"); 42 MODULE_LICENSE("GPL");
45 MODULE_AUTHOR("Paul E. McKenney <paulmck@linux 43 MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");
46 44
47 static bool disable_onoff_at_boot; 45 static bool disable_onoff_at_boot;
48 module_param(disable_onoff_at_boot, bool, 0444 46 module_param(disable_onoff_at_boot, bool, 0444);
49 47
50 static bool ftrace_dump_at_shutdown; 48 static bool ftrace_dump_at_shutdown;
51 module_param(ftrace_dump_at_shutdown, bool, 04 49 module_param(ftrace_dump_at_shutdown, bool, 0444);
52 50
53 static int verbose_sleep_frequency; 51 static int verbose_sleep_frequency;
54 module_param(verbose_sleep_frequency, int, 044 52 module_param(verbose_sleep_frequency, int, 0444);
55 53
56 static int verbose_sleep_duration = 1; 54 static int verbose_sleep_duration = 1;
57 module_param(verbose_sleep_duration, int, 0444 55 module_param(verbose_sleep_duration, int, 0444);
58 56
59 static int random_shuffle; <<
60 module_param(random_shuffle, int, 0444); <<
61 <<
62 static char *torture_type; 57 static char *torture_type;
63 static int verbose; 58 static int verbose;
64 59
65 /* Mediate rmmod and system shutdown. Concurr 60 /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
66 #define FULLSTOP_DONTSTOP 0 /* Normal oper 61 #define FULLSTOP_DONTSTOP 0 /* Normal operation. */
67 #define FULLSTOP_SHUTDOWN 1 /* System shut 62 #define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */
68 #define FULLSTOP_RMMOD 2 /* Normal rmmo 63 #define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */
69 static int fullstop = FULLSTOP_RMMOD; 64 static int fullstop = FULLSTOP_RMMOD;
70 static DEFINE_MUTEX(fullstop_mutex); 65 static DEFINE_MUTEX(fullstop_mutex);
71 66
72 static atomic_t verbose_sleep_counter; 67 static atomic_t verbose_sleep_counter;
73 68
74 /* 69 /*
75 * Sleep if needed from VERBOSE_TOROUT*(). 70 * Sleep if needed from VERBOSE_TOROUT*().
76 */ 71 */
77 void verbose_torout_sleep(void) 72 void verbose_torout_sleep(void)
78 { 73 {
79 if (verbose_sleep_frequency > 0 && 74 if (verbose_sleep_frequency > 0 &&
80 verbose_sleep_duration > 0 && 75 verbose_sleep_duration > 0 &&
81 !(atomic_inc_return(&verbose_sleep 76 !(atomic_inc_return(&verbose_sleep_counter) % verbose_sleep_frequency))
82 schedule_timeout_uninterruptib 77 schedule_timeout_uninterruptible(verbose_sleep_duration);
83 } 78 }
84 EXPORT_SYMBOL_GPL(verbose_torout_sleep); 79 EXPORT_SYMBOL_GPL(verbose_torout_sleep);
85 80
86 /* 81 /*
87 * Schedule a high-resolution-timer sleep in n 82 * Schedule a high-resolution-timer sleep in nanoseconds, with a 32-bit
88 * nanosecond random fuzz. This function and 83 * nanosecond random fuzz. This function and its friends desynchronize
89 * testing from the timer wheel. 84 * testing from the timer wheel.
90 */ 85 */
91 int torture_hrtimeout_ns(ktime_t baset_ns, u32 !! 86 int torture_hrtimeout_ns(ktime_t baset_ns, u32 fuzzt_ns, struct torture_random_state *trsp)
92 struct torture_random <<
93 { 87 {
94 ktime_t hto = baset_ns; 88 ktime_t hto = baset_ns;
95 89
96 if (trsp) 90 if (trsp)
97 hto += torture_random(trsp) % !! 91 hto += (torture_random(trsp) >> 3) % fuzzt_ns;
98 set_current_state(TASK_IDLE); !! 92 set_current_state(TASK_UNINTERRUPTIBLE);
99 return schedule_hrtimeout(&hto, mode); !! 93 return schedule_hrtimeout(&hto, HRTIMER_MODE_REL);
100 } 94 }
101 EXPORT_SYMBOL_GPL(torture_hrtimeout_ns); 95 EXPORT_SYMBOL_GPL(torture_hrtimeout_ns);
102 96
103 /* 97 /*
104 * Schedule a high-resolution-timer sleep in m 98 * Schedule a high-resolution-timer sleep in microseconds, with a 32-bit
105 * nanosecond (not microsecond!) random fuzz. 99 * nanosecond (not microsecond!) random fuzz.
106 */ 100 */
107 int torture_hrtimeout_us(u32 baset_us, u32 fuz 101 int torture_hrtimeout_us(u32 baset_us, u32 fuzzt_ns, struct torture_random_state *trsp)
108 { 102 {
109 ktime_t baset_ns = baset_us * NSEC_PER 103 ktime_t baset_ns = baset_us * NSEC_PER_USEC;
110 104
111 return torture_hrtimeout_ns(baset_ns, !! 105 return torture_hrtimeout_ns(baset_ns, fuzzt_ns, trsp);
112 } 106 }
113 EXPORT_SYMBOL_GPL(torture_hrtimeout_us); 107 EXPORT_SYMBOL_GPL(torture_hrtimeout_us);
114 108
115 /* 109 /*
116 * Schedule a high-resolution-timer sleep in m 110 * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit
117 * microsecond (not millisecond!) random fuzz. 111 * microsecond (not millisecond!) random fuzz.
118 */ 112 */
119 int torture_hrtimeout_ms(u32 baset_ms, u32 fuz 113 int torture_hrtimeout_ms(u32 baset_ms, u32 fuzzt_us, struct torture_random_state *trsp)
120 { 114 {
121 ktime_t baset_ns = baset_ms * NSEC_PER 115 ktime_t baset_ns = baset_ms * NSEC_PER_MSEC;
122 u32 fuzzt_ns; 116 u32 fuzzt_ns;
123 117
124 if ((u32)~0U / NSEC_PER_USEC < fuzzt_u 118 if ((u32)~0U / NSEC_PER_USEC < fuzzt_us)
125 fuzzt_ns = (u32)~0U; 119 fuzzt_ns = (u32)~0U;
126 else 120 else
127 fuzzt_ns = fuzzt_us * NSEC_PER 121 fuzzt_ns = fuzzt_us * NSEC_PER_USEC;
128 return torture_hrtimeout_ns(baset_ns, !! 122 return torture_hrtimeout_ns(baset_ns, fuzzt_ns, trsp);
129 } 123 }
130 EXPORT_SYMBOL_GPL(torture_hrtimeout_ms); 124 EXPORT_SYMBOL_GPL(torture_hrtimeout_ms);
131 125
132 /* 126 /*
133 * Schedule a high-resolution-timer sleep in j 127 * Schedule a high-resolution-timer sleep in jiffies, with an
134 * implied one-jiffy random fuzz. This is int 128 * implied one-jiffy random fuzz. This is intended to replace calls to
135 * schedule_timeout_interruptible() and friend 129 * schedule_timeout_interruptible() and friends.
136 */ 130 */
137 int torture_hrtimeout_jiffies(u32 baset_j, str 131 int torture_hrtimeout_jiffies(u32 baset_j, struct torture_random_state *trsp)
138 { 132 {
139 ktime_t baset_ns = jiffies_to_nsecs(ba 133 ktime_t baset_ns = jiffies_to_nsecs(baset_j);
140 134
141 return torture_hrtimeout_ns(baset_ns, !! 135 return torture_hrtimeout_ns(baset_ns, jiffies_to_nsecs(1), trsp);
142 } 136 }
143 EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies); 137 EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies);
144 138
145 /* 139 /*
146 * Schedule a high-resolution-timer sleep in m 140 * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit
147 * millisecond (not second!) random fuzz. 141 * millisecond (not second!) random fuzz.
148 */ 142 */
149 int torture_hrtimeout_s(u32 baset_s, u32 fuzzt 143 int torture_hrtimeout_s(u32 baset_s, u32 fuzzt_ms, struct torture_random_state *trsp)
150 { 144 {
151 ktime_t baset_ns = baset_s * NSEC_PER_ 145 ktime_t baset_ns = baset_s * NSEC_PER_SEC;
152 u32 fuzzt_ns; 146 u32 fuzzt_ns;
153 147
154 if ((u32)~0U / NSEC_PER_MSEC < fuzzt_m 148 if ((u32)~0U / NSEC_PER_MSEC < fuzzt_ms)
155 fuzzt_ns = (u32)~0U; 149 fuzzt_ns = (u32)~0U;
156 else 150 else
157 fuzzt_ns = fuzzt_ms * NSEC_PER 151 fuzzt_ns = fuzzt_ms * NSEC_PER_MSEC;
158 return torture_hrtimeout_ns(baset_ns, !! 152 return torture_hrtimeout_ns(baset_ns, fuzzt_ns, trsp);
159 } 153 }
160 EXPORT_SYMBOL_GPL(torture_hrtimeout_s); 154 EXPORT_SYMBOL_GPL(torture_hrtimeout_s);
161 155
162 #ifdef CONFIG_HOTPLUG_CPU 156 #ifdef CONFIG_HOTPLUG_CPU
163 157
164 /* 158 /*
165 * Variables for online-offline handling. Onl 159 * Variables for online-offline handling. Only present if CPU hotplug
166 * is enabled, otherwise does nothing. 160 * is enabled, otherwise does nothing.
167 */ 161 */
168 162
169 static struct task_struct *onoff_task; 163 static struct task_struct *onoff_task;
170 static long onoff_holdoff; 164 static long onoff_holdoff;
171 static long onoff_interval; 165 static long onoff_interval;
172 static torture_ofl_func *onoff_f; 166 static torture_ofl_func *onoff_f;
173 static long n_offline_attempts; 167 static long n_offline_attempts;
174 static long n_offline_successes; 168 static long n_offline_successes;
175 static unsigned long sum_offline; 169 static unsigned long sum_offline;
176 static int min_offline = -1; 170 static int min_offline = -1;
177 static int max_offline; 171 static int max_offline;
178 static long n_online_attempts; 172 static long n_online_attempts;
179 static long n_online_successes; 173 static long n_online_successes;
180 static unsigned long sum_online; 174 static unsigned long sum_online;
181 static int min_online = -1; 175 static int min_online = -1;
182 static int max_online; 176 static int max_online;
183 177
184 static int torture_online_cpus = NR_CPUS; 178 static int torture_online_cpus = NR_CPUS;
185 179
186 /* 180 /*
187 * Some torture testing leverages confusion as 181 * Some torture testing leverages confusion as to the number of online
188 * CPUs. This function returns the torture-te 182 * CPUs. This function returns the torture-testing view of this number,
189 * which allows torture tests to load-balance 183 * which allows torture tests to load-balance appropriately.
190 */ 184 */
191 int torture_num_online_cpus(void) 185 int torture_num_online_cpus(void)
192 { 186 {
193 return READ_ONCE(torture_online_cpus); 187 return READ_ONCE(torture_online_cpus);
194 } 188 }
195 EXPORT_SYMBOL_GPL(torture_num_online_cpus); 189 EXPORT_SYMBOL_GPL(torture_num_online_cpus);
196 190
197 /* 191 /*
198 * Attempt to take a CPU offline. Return fals 192 * Attempt to take a CPU offline. Return false if the CPU is already
199 * offline or if it is not subject to CPU-hotp 193 * offline or if it is not subject to CPU-hotplug operations. The
200 * caller can detect other failures by looking 194 * caller can detect other failures by looking at the statistics.
201 */ 195 */
202 bool torture_offline(int cpu, long *n_offl_att 196 bool torture_offline(int cpu, long *n_offl_attempts, long *n_offl_successes,
203 unsigned long *sum_offl, 197 unsigned long *sum_offl, int *min_offl, int *max_offl)
204 { 198 {
205 unsigned long delta; 199 unsigned long delta;
206 int ret; 200 int ret;
207 char *s; 201 char *s;
208 unsigned long starttime; 202 unsigned long starttime;
209 203
210 if (!cpu_online(cpu) || !cpu_is_hotplu 204 if (!cpu_online(cpu) || !cpu_is_hotpluggable(cpu))
211 return false; 205 return false;
212 if (num_online_cpus() <= 1) 206 if (num_online_cpus() <= 1)
213 return false; /* Can't offlin 207 return false; /* Can't offline the last CPU. */
214 208
215 if (verbose > 1) 209 if (verbose > 1)
216 pr_alert("%s" TORTURE_FLAG 210 pr_alert("%s" TORTURE_FLAG
217 "torture_onoff task: 211 "torture_onoff task: offlining %d\n",
218 torture_type, cpu); 212 torture_type, cpu);
219 starttime = jiffies; 213 starttime = jiffies;
220 (*n_offl_attempts)++; 214 (*n_offl_attempts)++;
221 ret = remove_cpu(cpu); 215 ret = remove_cpu(cpu);
222 if (ret) { 216 if (ret) {
223 s = ""; 217 s = "";
224 if (!rcu_inkernel_boot_has_end 218 if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) {
225 // PCI probe frequentl 219 // PCI probe frequently disables hotplug during boot.
226 (*n_offl_attempts)--; 220 (*n_offl_attempts)--;
227 s = " (-EBUSY forgiven 221 s = " (-EBUSY forgiven during boot)";
228 } 222 }
229 if (verbose) 223 if (verbose)
230 pr_alert("%s" TORTURE_ 224 pr_alert("%s" TORTURE_FLAG
231 "torture_onof 225 "torture_onoff task: offline %d failed%s: errno %d\n",
232 torture_type, 226 torture_type, cpu, s, ret);
233 } else { 227 } else {
234 if (verbose > 1) 228 if (verbose > 1)
235 pr_alert("%s" TORTURE_ 229 pr_alert("%s" TORTURE_FLAG
236 "torture_onof 230 "torture_onoff task: offlined %d\n",
237 torture_type, 231 torture_type, cpu);
238 if (onoff_f) 232 if (onoff_f)
239 onoff_f(); 233 onoff_f();
240 (*n_offl_successes)++; 234 (*n_offl_successes)++;
241 delta = jiffies - starttime; 235 delta = jiffies - starttime;
242 *sum_offl += delta; 236 *sum_offl += delta;
243 if (*min_offl < 0) { 237 if (*min_offl < 0) {
244 *min_offl = delta; 238 *min_offl = delta;
245 *max_offl = delta; 239 *max_offl = delta;
246 } 240 }
247 if (*min_offl > delta) 241 if (*min_offl > delta)
248 *min_offl = delta; 242 *min_offl = delta;
249 if (*max_offl < delta) 243 if (*max_offl < delta)
250 *max_offl = delta; 244 *max_offl = delta;
251 WRITE_ONCE(torture_online_cpus 245 WRITE_ONCE(torture_online_cpus, torture_online_cpus - 1);
252 WARN_ON_ONCE(torture_online_cp 246 WARN_ON_ONCE(torture_online_cpus <= 0);
253 } 247 }
254 248
255 return true; 249 return true;
256 } 250 }
257 EXPORT_SYMBOL_GPL(torture_offline); 251 EXPORT_SYMBOL_GPL(torture_offline);
258 252
259 /* 253 /*
260 * Attempt to bring a CPU online. Return fals 254 * Attempt to bring a CPU online. Return false if the CPU is already
261 * online or if it is not subject to CPU-hotpl 255 * online or if it is not subject to CPU-hotplug operations. The
262 * caller can detect other failures by looking 256 * caller can detect other failures by looking at the statistics.
263 */ 257 */
264 bool torture_online(int cpu, long *n_onl_attem 258 bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes,
265 unsigned long *sum_onl, in 259 unsigned long *sum_onl, int *min_onl, int *max_onl)
266 { 260 {
267 unsigned long delta; 261 unsigned long delta;
268 int ret; 262 int ret;
269 char *s; 263 char *s;
270 unsigned long starttime; 264 unsigned long starttime;
271 265
272 if (cpu_online(cpu) || !cpu_is_hotplug 266 if (cpu_online(cpu) || !cpu_is_hotpluggable(cpu))
273 return false; 267 return false;
274 268
275 if (verbose > 1) 269 if (verbose > 1)
276 pr_alert("%s" TORTURE_FLAG 270 pr_alert("%s" TORTURE_FLAG
277 "torture_onoff task: 271 "torture_onoff task: onlining %d\n",
278 torture_type, cpu); 272 torture_type, cpu);
279 starttime = jiffies; 273 starttime = jiffies;
280 (*n_onl_attempts)++; 274 (*n_onl_attempts)++;
281 ret = add_cpu(cpu); 275 ret = add_cpu(cpu);
282 if (ret) { 276 if (ret) {
283 s = ""; 277 s = "";
284 if (!rcu_inkernel_boot_has_end 278 if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) {
285 // PCI probe frequentl 279 // PCI probe frequently disables hotplug during boot.
286 (*n_onl_attempts)--; 280 (*n_onl_attempts)--;
287 s = " (-EBUSY forgiven 281 s = " (-EBUSY forgiven during boot)";
288 } 282 }
289 if (verbose) 283 if (verbose)
290 pr_alert("%s" TORTURE_ 284 pr_alert("%s" TORTURE_FLAG
291 "torture_onof 285 "torture_onoff task: online %d failed%s: errno %d\n",
292 torture_type, 286 torture_type, cpu, s, ret);
293 } else { 287 } else {
294 if (verbose > 1) 288 if (verbose > 1)
295 pr_alert("%s" TORTURE_ 289 pr_alert("%s" TORTURE_FLAG
296 "torture_onof 290 "torture_onoff task: onlined %d\n",
297 torture_type, 291 torture_type, cpu);
298 (*n_onl_successes)++; 292 (*n_onl_successes)++;
299 delta = jiffies - starttime; 293 delta = jiffies - starttime;
300 *sum_onl += delta; 294 *sum_onl += delta;
301 if (*min_onl < 0) { 295 if (*min_onl < 0) {
302 *min_onl = delta; 296 *min_onl = delta;
303 *max_onl = delta; 297 *max_onl = delta;
304 } 298 }
305 if (*min_onl > delta) 299 if (*min_onl > delta)
306 *min_onl = delta; 300 *min_onl = delta;
307 if (*max_onl < delta) 301 if (*max_onl < delta)
308 *max_onl = delta; 302 *max_onl = delta;
309 WRITE_ONCE(torture_online_cpus 303 WRITE_ONCE(torture_online_cpus, torture_online_cpus + 1);
310 } 304 }
311 305
312 return true; 306 return true;
313 } 307 }
314 EXPORT_SYMBOL_GPL(torture_online); 308 EXPORT_SYMBOL_GPL(torture_online);
315 309
316 /* 310 /*
317 * Get everything online at the beginning and 311 * Get everything online at the beginning and ends of tests.
318 */ 312 */
319 static void torture_online_all(char *phase) 313 static void torture_online_all(char *phase)
320 { 314 {
321 int cpu; 315 int cpu;
322 int ret; 316 int ret;
323 317
324 for_each_possible_cpu(cpu) { 318 for_each_possible_cpu(cpu) {
325 if (cpu_online(cpu)) 319 if (cpu_online(cpu))
326 continue; 320 continue;
327 ret = add_cpu(cpu); 321 ret = add_cpu(cpu);
328 if (ret && verbose) { 322 if (ret && verbose) {
329 pr_alert("%s" TORTURE_ 323 pr_alert("%s" TORTURE_FLAG
330 "%s: %s onlin 324 "%s: %s online %d: errno %d\n",
331 __func__, pha 325 __func__, phase, torture_type, cpu, ret);
332 } 326 }
333 } 327 }
334 } 328 }
335 329
336 /* 330 /*
337 * Execute random CPU-hotplug operations at th 331 * Execute random CPU-hotplug operations at the interval specified
338 * by the onoff_interval. 332 * by the onoff_interval.
339 */ 333 */
340 static int 334 static int
341 torture_onoff(void *arg) 335 torture_onoff(void *arg)
342 { 336 {
343 int cpu; 337 int cpu;
344 int maxcpu = -1; 338 int maxcpu = -1;
345 DEFINE_TORTURE_RANDOM(rand); 339 DEFINE_TORTURE_RANDOM(rand);
346 340
347 VERBOSE_TOROUT_STRING("torture_onoff t 341 VERBOSE_TOROUT_STRING("torture_onoff task started");
348 for_each_online_cpu(cpu) 342 for_each_online_cpu(cpu)
349 maxcpu = cpu; 343 maxcpu = cpu;
350 WARN_ON(maxcpu < 0); 344 WARN_ON(maxcpu < 0);
351 torture_online_all("Initial"); 345 torture_online_all("Initial");
352 if (maxcpu == 0) { 346 if (maxcpu == 0) {
353 VERBOSE_TOROUT_STRING("Only on 347 VERBOSE_TOROUT_STRING("Only one CPU, so CPU-hotplug testing is disabled");
354 goto stop; 348 goto stop;
355 } 349 }
356 350
357 if (onoff_holdoff > 0) { 351 if (onoff_holdoff > 0) {
358 VERBOSE_TOROUT_STRING("torture 352 VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
359 torture_hrtimeout_jiffies(onof !! 353 schedule_timeout_interruptible(onoff_holdoff);
360 VERBOSE_TOROUT_STRING("torture 354 VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
361 } 355 }
362 while (!torture_must_stop()) { 356 while (!torture_must_stop()) {
363 if (disable_onoff_at_boot && ! 357 if (disable_onoff_at_boot && !rcu_inkernel_boot_has_ended()) {
364 torture_hrtimeout_jiff !! 358 schedule_timeout_interruptible(HZ / 10);
365 continue; 359 continue;
366 } 360 }
367 cpu = torture_random(&rand) % !! 361 cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
368 if (!torture_offline(cpu, 362 if (!torture_offline(cpu,
369 &n_offlin 363 &n_offline_attempts, &n_offline_successes,
370 &sum_offl 364 &sum_offline, &min_offline, &max_offline))
371 torture_online(cpu, 365 torture_online(cpu,
372 &n_onli 366 &n_online_attempts, &n_online_successes,
373 &sum_on 367 &sum_online, &min_online, &max_online);
374 torture_hrtimeout_jiffies(onof !! 368 schedule_timeout_interruptible(onoff_interval);
375 } 369 }
376 370
377 stop: 371 stop:
378 torture_kthread_stopping("torture_onof 372 torture_kthread_stopping("torture_onoff");
379 torture_online_all("Final"); 373 torture_online_all("Final");
380 return 0; 374 return 0;
381 } 375 }
382 376
383 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 377 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
384 378
385 /* 379 /*
386 * Initiate online-offline handling. 380 * Initiate online-offline handling.
387 */ 381 */
388 int torture_onoff_init(long ooholdoff, long oo 382 int torture_onoff_init(long ooholdoff, long oointerval, torture_ofl_func *f)
389 { 383 {
390 #ifdef CONFIG_HOTPLUG_CPU 384 #ifdef CONFIG_HOTPLUG_CPU
391 onoff_holdoff = ooholdoff; 385 onoff_holdoff = ooholdoff;
392 onoff_interval = oointerval; 386 onoff_interval = oointerval;
393 onoff_f = f; 387 onoff_f = f;
394 if (onoff_interval <= 0) 388 if (onoff_interval <= 0)
395 return 0; 389 return 0;
396 return torture_create_kthread(torture_ 390 return torture_create_kthread(torture_onoff, NULL, onoff_task);
397 #else /* #ifdef CONFIG_HOTPLUG_CPU */ 391 #else /* #ifdef CONFIG_HOTPLUG_CPU */
398 return 0; 392 return 0;
399 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ 393 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
400 } 394 }
401 EXPORT_SYMBOL_GPL(torture_onoff_init); 395 EXPORT_SYMBOL_GPL(torture_onoff_init);
402 396
403 /* 397 /*
404 * Clean up after online/offline testing. 398 * Clean up after online/offline testing.
405 */ 399 */
406 static void torture_onoff_cleanup(void) 400 static void torture_onoff_cleanup(void)
407 { 401 {
408 #ifdef CONFIG_HOTPLUG_CPU 402 #ifdef CONFIG_HOTPLUG_CPU
409 if (onoff_task == NULL) 403 if (onoff_task == NULL)
410 return; 404 return;
411 VERBOSE_TOROUT_STRING("Stopping tortur 405 VERBOSE_TOROUT_STRING("Stopping torture_onoff task");
412 kthread_stop(onoff_task); 406 kthread_stop(onoff_task);
413 onoff_task = NULL; 407 onoff_task = NULL;
414 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 408 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
415 } 409 }
416 410
417 /* 411 /*
418 * Print online/offline testing statistics. 412 * Print online/offline testing statistics.
419 */ 413 */
420 void torture_onoff_stats(void) 414 void torture_onoff_stats(void)
421 { 415 {
422 #ifdef CONFIG_HOTPLUG_CPU 416 #ifdef CONFIG_HOTPLUG_CPU
423 pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d: 417 pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
424 n_online_successes, n_online_a 418 n_online_successes, n_online_attempts,
425 n_offline_successes, n_offline 419 n_offline_successes, n_offline_attempts,
426 min_online, max_online, 420 min_online, max_online,
427 min_offline, max_offline, 421 min_offline, max_offline,
428 sum_online, sum_offline, HZ); 422 sum_online, sum_offline, HZ);
429 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 423 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
430 } 424 }
431 EXPORT_SYMBOL_GPL(torture_onoff_stats); 425 EXPORT_SYMBOL_GPL(torture_onoff_stats);
432 426
433 /* 427 /*
434 * Were all the online/offline operations succ 428 * Were all the online/offline operations successful?
435 */ 429 */
436 bool torture_onoff_failures(void) 430 bool torture_onoff_failures(void)
437 { 431 {
438 #ifdef CONFIG_HOTPLUG_CPU 432 #ifdef CONFIG_HOTPLUG_CPU
439 return n_online_successes != n_online_ 433 return n_online_successes != n_online_attempts ||
440 n_offline_successes != n_offlin 434 n_offline_successes != n_offline_attempts;
441 #else /* #ifdef CONFIG_HOTPLUG_CPU */ 435 #else /* #ifdef CONFIG_HOTPLUG_CPU */
442 return false; 436 return false;
443 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ 437 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
444 } 438 }
445 EXPORT_SYMBOL_GPL(torture_onoff_failures); 439 EXPORT_SYMBOL_GPL(torture_onoff_failures);
446 440
447 #define TORTURE_RANDOM_MULT 39916801 /* p 441 #define TORTURE_RANDOM_MULT 39916801 /* prime */
448 #define TORTURE_RANDOM_ADD 479001701 /* p 442 #define TORTURE_RANDOM_ADD 479001701 /* prime */
449 #define TORTURE_RANDOM_REFRESH 10000 443 #define TORTURE_RANDOM_REFRESH 10000
450 444
451 /* 445 /*
452 * Crude but fast random-number generator. Us 446 * Crude but fast random-number generator. Uses a linear congruential
453 * generator, with occasional help from cpu_cl 447 * generator, with occasional help from cpu_clock().
454 */ 448 */
455 unsigned long 449 unsigned long
456 torture_random(struct torture_random_state *tr 450 torture_random(struct torture_random_state *trsp)
457 { 451 {
458 if (--trsp->trs_count < 0) { 452 if (--trsp->trs_count < 0) {
459 trsp->trs_state += (unsigned l !! 453 trsp->trs_state += (unsigned long)local_clock();
460 trsp->trs_count = TORTURE_RAND 454 trsp->trs_count = TORTURE_RANDOM_REFRESH;
461 } 455 }
462 trsp->trs_state = trsp->trs_state * TO 456 trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
463 TORTURE_RANDOM_ADD; 457 TORTURE_RANDOM_ADD;
464 return swahw32(trsp->trs_state); 458 return swahw32(trsp->trs_state);
465 } 459 }
466 EXPORT_SYMBOL_GPL(torture_random); 460 EXPORT_SYMBOL_GPL(torture_random);
467 461
468 /* 462 /*
469 * Variables for shuffling. The idea is to en 463 * Variables for shuffling. The idea is to ensure that each CPU stays
470 * idle for an extended period to test interac 464 * idle for an extended period to test interactions with dyntick idle,
471 * as well as interactions with any per-CPU va 465 * as well as interactions with any per-CPU variables.
472 */ 466 */
473 struct shuffle_task { 467 struct shuffle_task {
474 struct list_head st_l; 468 struct list_head st_l;
475 struct task_struct *st_t; 469 struct task_struct *st_t;
476 }; 470 };
477 471
478 static long shuffle_interval; /* In jiffies. 472 static long shuffle_interval; /* In jiffies. */
479 static struct task_struct *shuffler_task; 473 static struct task_struct *shuffler_task;
480 static cpumask_var_t shuffle_tmp_mask; 474 static cpumask_var_t shuffle_tmp_mask;
481 static int shuffle_idle_cpu; /* Force all t 475 static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */
482 static struct list_head shuffle_task_list = LI 476 static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);
483 static DEFINE_MUTEX(shuffle_task_mutex); 477 static DEFINE_MUTEX(shuffle_task_mutex);
484 478
485 /* 479 /*
486 * Register a task to be shuffled. If there i 480 * Register a task to be shuffled. If there is no memory, just splat
487 * and don't bother registering. 481 * and don't bother registering.
488 */ 482 */
489 void torture_shuffle_task_register(struct task 483 void torture_shuffle_task_register(struct task_struct *tp)
490 { 484 {
491 struct shuffle_task *stp; 485 struct shuffle_task *stp;
492 486
493 if (WARN_ON_ONCE(tp == NULL)) 487 if (WARN_ON_ONCE(tp == NULL))
494 return; 488 return;
495 stp = kmalloc(sizeof(*stp), GFP_KERNEL 489 stp = kmalloc(sizeof(*stp), GFP_KERNEL);
496 if (WARN_ON_ONCE(stp == NULL)) 490 if (WARN_ON_ONCE(stp == NULL))
497 return; 491 return;
498 stp->st_t = tp; 492 stp->st_t = tp;
499 mutex_lock(&shuffle_task_mutex); 493 mutex_lock(&shuffle_task_mutex);
500 list_add(&stp->st_l, &shuffle_task_lis 494 list_add(&stp->st_l, &shuffle_task_list);
501 mutex_unlock(&shuffle_task_mutex); 495 mutex_unlock(&shuffle_task_mutex);
502 } 496 }
503 EXPORT_SYMBOL_GPL(torture_shuffle_task_registe 497 EXPORT_SYMBOL_GPL(torture_shuffle_task_register);
504 498
505 /* 499 /*
506 * Unregister all tasks, for example, at the e 500 * Unregister all tasks, for example, at the end of the torture run.
507 */ 501 */
508 static void torture_shuffle_task_unregister_al 502 static void torture_shuffle_task_unregister_all(void)
509 { 503 {
510 struct shuffle_task *stp; 504 struct shuffle_task *stp;
511 struct shuffle_task *p; 505 struct shuffle_task *p;
512 506
513 mutex_lock(&shuffle_task_mutex); 507 mutex_lock(&shuffle_task_mutex);
514 list_for_each_entry_safe(stp, p, &shuf 508 list_for_each_entry_safe(stp, p, &shuffle_task_list, st_l) {
515 list_del(&stp->st_l); 509 list_del(&stp->st_l);
516 kfree(stp); 510 kfree(stp);
517 } 511 }
518 mutex_unlock(&shuffle_task_mutex); 512 mutex_unlock(&shuffle_task_mutex);
519 } 513 }
520 514
521 /* Shuffle tasks such that we allow shuffle_id 515 /* Shuffle tasks such that we allow shuffle_idle_cpu to become idle.
522 * A special case is when shuffle_idle_cpu = - 516 * A special case is when shuffle_idle_cpu = -1, in which case we allow
523 * the tasks to run on all CPUs. 517 * the tasks to run on all CPUs.
524 */ 518 */
525 static void torture_shuffle_tasks(struct tortu !! 519 static void torture_shuffle_tasks(void)
526 { 520 {
527 struct shuffle_task *stp; 521 struct shuffle_task *stp;
528 522
529 cpumask_setall(shuffle_tmp_mask); 523 cpumask_setall(shuffle_tmp_mask);
530 cpus_read_lock(); 524 cpus_read_lock();
531 525
532 /* No point in shuffling if there is o 526 /* No point in shuffling if there is only one online CPU (ex: UP) */
533 if (num_online_cpus() == 1) { 527 if (num_online_cpus() == 1) {
534 cpus_read_unlock(); 528 cpus_read_unlock();
535 return; 529 return;
536 } 530 }
537 531
538 /* Advance to the next CPU. Upon over 532 /* Advance to the next CPU. Upon overflow, don't idle any CPUs. */
539 shuffle_idle_cpu = cpumask_next(shuffl 533 shuffle_idle_cpu = cpumask_next(shuffle_idle_cpu, shuffle_tmp_mask);
540 if (shuffle_idle_cpu >= nr_cpu_ids) 534 if (shuffle_idle_cpu >= nr_cpu_ids)
541 shuffle_idle_cpu = -1; 535 shuffle_idle_cpu = -1;
542 else 536 else
543 cpumask_clear_cpu(shuffle_idle 537 cpumask_clear_cpu(shuffle_idle_cpu, shuffle_tmp_mask);
544 538
545 mutex_lock(&shuffle_task_mutex); 539 mutex_lock(&shuffle_task_mutex);
546 list_for_each_entry(stp, &shuffle_task !! 540 list_for_each_entry(stp, &shuffle_task_list, st_l)
547 if (!random_shuffle || torture !! 541 set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
548 set_cpus_allowed_ptr(s <<
549 } <<
550 mutex_unlock(&shuffle_task_mutex); 542 mutex_unlock(&shuffle_task_mutex);
551 543
552 cpus_read_unlock(); 544 cpus_read_unlock();
553 } 545 }
554 546
555 /* Shuffle tasks across CPUs, with the intent 547 /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
556 * system to become idle at a time and cut off 548 * system to become idle at a time and cut off its timer ticks. This is meant
557 * to test the support for such tickless idle 549 * to test the support for such tickless idle CPU in RCU.
558 */ 550 */
559 static int torture_shuffle(void *arg) 551 static int torture_shuffle(void *arg)
560 { 552 {
561 DEFINE_TORTURE_RANDOM(rand); <<
562 <<
563 VERBOSE_TOROUT_STRING("torture_shuffle 553 VERBOSE_TOROUT_STRING("torture_shuffle task started");
564 do { 554 do {
565 torture_hrtimeout_jiffies(shuf !! 555 schedule_timeout_interruptible(shuffle_interval);
566 torture_shuffle_tasks(&rand); !! 556 torture_shuffle_tasks();
567 torture_shutdown_absorb("tortu 557 torture_shutdown_absorb("torture_shuffle");
568 } while (!torture_must_stop()); 558 } while (!torture_must_stop());
569 torture_kthread_stopping("torture_shuf 559 torture_kthread_stopping("torture_shuffle");
570 return 0; 560 return 0;
571 } 561 }
572 562
573 /* 563 /*
574 * Start the shuffler, with shuffint in jiffie 564 * Start the shuffler, with shuffint in jiffies.
575 */ 565 */
576 int torture_shuffle_init(long shuffint) 566 int torture_shuffle_init(long shuffint)
577 { 567 {
578 shuffle_interval = shuffint; 568 shuffle_interval = shuffint;
579 569
580 shuffle_idle_cpu = -1; 570 shuffle_idle_cpu = -1;
581 571
582 if (!alloc_cpumask_var(&shuffle_tmp_ma 572 if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
583 TOROUT_ERRSTRING("Failed to al 573 TOROUT_ERRSTRING("Failed to alloc mask");
584 return -ENOMEM; 574 return -ENOMEM;
585 } 575 }
586 576
587 /* Create the shuffler thread */ 577 /* Create the shuffler thread */
588 return torture_create_kthread(torture_ 578 return torture_create_kthread(torture_shuffle, NULL, shuffler_task);
589 } 579 }
590 EXPORT_SYMBOL_GPL(torture_shuffle_init); 580 EXPORT_SYMBOL_GPL(torture_shuffle_init);
591 581
592 /* 582 /*
593 * Stop the shuffling. 583 * Stop the shuffling.
594 */ 584 */
595 static void torture_shuffle_cleanup(void) 585 static void torture_shuffle_cleanup(void)
596 { 586 {
597 torture_shuffle_task_unregister_all(); 587 torture_shuffle_task_unregister_all();
598 if (shuffler_task) { 588 if (shuffler_task) {
599 VERBOSE_TOROUT_STRING("Stoppin 589 VERBOSE_TOROUT_STRING("Stopping torture_shuffle task");
600 kthread_stop(shuffler_task); 590 kthread_stop(shuffler_task);
601 free_cpumask_var(shuffle_tmp_m 591 free_cpumask_var(shuffle_tmp_mask);
602 } 592 }
603 shuffler_task = NULL; 593 shuffler_task = NULL;
604 } 594 }
605 595
606 /* 596 /*
607 * Variables for auto-shutdown. This allows " 597 * Variables for auto-shutdown. This allows "lights out" torture runs
608 * to be fully scripted. 598 * to be fully scripted.
609 */ 599 */
610 static struct task_struct *shutdown_task; 600 static struct task_struct *shutdown_task;
611 static ktime_t shutdown_time; /* tim 601 static ktime_t shutdown_time; /* time to system shutdown. */
612 static void (*torture_shutdown_hook)(void); 602 static void (*torture_shutdown_hook)(void);
613 603
614 /* 604 /*
615 * Absorb kthreads into a kernel function that 605 * Absorb kthreads into a kernel function that won't return, so that
616 * they won't ever access module text or data 606 * they won't ever access module text or data again.
617 */ 607 */
618 void torture_shutdown_absorb(const char *title 608 void torture_shutdown_absorb(const char *title)
619 { 609 {
620 while (READ_ONCE(fullstop) == FULLSTOP 610 while (READ_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
621 pr_notice("torture thread %s p 611 pr_notice("torture thread %s parking due to system shutdown\n",
622 title); 612 title);
623 schedule_timeout_uninterruptib 613 schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
624 } 614 }
625 } 615 }
626 EXPORT_SYMBOL_GPL(torture_shutdown_absorb); 616 EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
627 617
628 /* 618 /*
629 * Cause the torture test to shutdown the syst 619 * Cause the torture test to shutdown the system after the test has
630 * run for the time specified by the shutdown_ 620 * run for the time specified by the shutdown_secs parameter.
631 */ 621 */
632 static int torture_shutdown(void *arg) 622 static int torture_shutdown(void *arg)
633 { 623 {
634 ktime_t ktime_snap; 624 ktime_t ktime_snap;
635 625
636 VERBOSE_TOROUT_STRING("torture_shutdow 626 VERBOSE_TOROUT_STRING("torture_shutdown task started");
637 ktime_snap = ktime_get(); 627 ktime_snap = ktime_get();
638 while (ktime_before(ktime_snap, shutdo 628 while (ktime_before(ktime_snap, shutdown_time) &&
639 !torture_must_stop()) { 629 !torture_must_stop()) {
640 if (verbose) 630 if (verbose)
641 pr_alert("%s" TORTURE_ 631 pr_alert("%s" TORTURE_FLAG
642 "torture_shut 632 "torture_shutdown task: %llu ms remaining\n",
643 torture_type, 633 torture_type,
644 ktime_ms_delt 634 ktime_ms_delta(shutdown_time, ktime_snap));
645 set_current_state(TASK_INTERRU 635 set_current_state(TASK_INTERRUPTIBLE);
646 schedule_hrtimeout(&shutdown_t 636 schedule_hrtimeout(&shutdown_time, HRTIMER_MODE_ABS);
647 ktime_snap = ktime_get(); 637 ktime_snap = ktime_get();
648 } 638 }
649 if (torture_must_stop()) { 639 if (torture_must_stop()) {
650 torture_kthread_stopping("tort 640 torture_kthread_stopping("torture_shutdown");
651 return 0; 641 return 0;
652 } 642 }
653 643
654 /* OK, shut down the system. */ 644 /* OK, shut down the system. */
655 645
656 VERBOSE_TOROUT_STRING("torture_shutdow 646 VERBOSE_TOROUT_STRING("torture_shutdown task shutting down system");
657 shutdown_task = NULL; /* Avoid self- 647 shutdown_task = NULL; /* Avoid self-kill deadlock. */
658 if (torture_shutdown_hook) 648 if (torture_shutdown_hook)
659 torture_shutdown_hook(); 649 torture_shutdown_hook();
660 else 650 else
661 VERBOSE_TOROUT_STRING("No tort 651 VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
662 if (ftrace_dump_at_shutdown) 652 if (ftrace_dump_at_shutdown)
663 rcu_ftrace_dump(DUMP_ALL); 653 rcu_ftrace_dump(DUMP_ALL);
664 kernel_power_off(); /* Shut down t 654 kernel_power_off(); /* Shut down the system. */
665 return 0; 655 return 0;
666 } 656 }
667 657
668 /* 658 /*
669 * Start up the shutdown task. 659 * Start up the shutdown task.
670 */ 660 */
671 int torture_shutdown_init(int ssecs, void (*cl 661 int torture_shutdown_init(int ssecs, void (*cleanup)(void))
672 { 662 {
673 torture_shutdown_hook = cleanup; 663 torture_shutdown_hook = cleanup;
674 if (ssecs > 0) { 664 if (ssecs > 0) {
675 shutdown_time = ktime_add(ktim 665 shutdown_time = ktime_add(ktime_get(), ktime_set(ssecs, 0));
676 return torture_create_kthread( 666 return torture_create_kthread(torture_shutdown, NULL,
677 !! 667 shutdown_task);
678 } 668 }
679 return 0; 669 return 0;
680 } 670 }
681 EXPORT_SYMBOL_GPL(torture_shutdown_init); 671 EXPORT_SYMBOL_GPL(torture_shutdown_init);
682 672
683 /* 673 /*
684 * Detect and respond to a system shutdown. 674 * Detect and respond to a system shutdown.
685 */ 675 */
686 static int torture_shutdown_notify(struct noti 676 static int torture_shutdown_notify(struct notifier_block *unused1,
687 unsigned lo 677 unsigned long unused2, void *unused3)
688 { 678 {
689 mutex_lock(&fullstop_mutex); 679 mutex_lock(&fullstop_mutex);
690 if (READ_ONCE(fullstop) == FULLSTOP_DO 680 if (READ_ONCE(fullstop) == FULLSTOP_DONTSTOP) {
691 VERBOSE_TOROUT_STRING("Unsched 681 VERBOSE_TOROUT_STRING("Unscheduled system shutdown detected");
692 WRITE_ONCE(fullstop, FULLSTOP_ 682 WRITE_ONCE(fullstop, FULLSTOP_SHUTDOWN);
693 } else { 683 } else {
694 pr_warn("Concurrent rmmod and 684 pr_warn("Concurrent rmmod and shutdown illegal!\n");
695 } 685 }
696 mutex_unlock(&fullstop_mutex); 686 mutex_unlock(&fullstop_mutex);
697 return NOTIFY_DONE; 687 return NOTIFY_DONE;
698 } 688 }
699 689
700 static struct notifier_block torture_shutdown_ 690 static struct notifier_block torture_shutdown_nb = {
701 .notifier_call = torture_shutdown_noti 691 .notifier_call = torture_shutdown_notify,
702 }; 692 };
703 693
704 /* 694 /*
705 * Shut down the shutdown task. Say what??? 695 * Shut down the shutdown task. Say what??? Heh! This can happen if
706 * the torture module gets an rmmod before the 696 * the torture module gets an rmmod before the shutdown time arrives. ;-)
707 */ 697 */
708 static void torture_shutdown_cleanup(void) 698 static void torture_shutdown_cleanup(void)
709 { 699 {
710 unregister_reboot_notifier(&torture_sh 700 unregister_reboot_notifier(&torture_shutdown_nb);
711 if (shutdown_task != NULL) { 701 if (shutdown_task != NULL) {
712 VERBOSE_TOROUT_STRING("Stoppin 702 VERBOSE_TOROUT_STRING("Stopping torture_shutdown task");
713 kthread_stop(shutdown_task); 703 kthread_stop(shutdown_task);
714 } 704 }
715 shutdown_task = NULL; 705 shutdown_task = NULL;
716 } 706 }
717 707
718 /* 708 /*
719 * Variables for stuttering, which means to pe 709 * Variables for stuttering, which means to periodically pause and
720 * restart testing in order to catch bugs that 710 * restart testing in order to catch bugs that appear when load is
721 * suddenly applied to or removed from the sys 711 * suddenly applied to or removed from the system.
722 */ 712 */
723 static struct task_struct *stutter_task; 713 static struct task_struct *stutter_task;
724 static ktime_t stutter_till_abs_time; !! 714 static int stutter_pause_test;
725 static int stutter; 715 static int stutter;
726 static int stutter_gap; 716 static int stutter_gap;
727 717
728 /* 718 /*
729 * Block until the stutter interval ends. Thi 719 * Block until the stutter interval ends. This must be called periodically
730 * by all running kthreads that need to be sub 720 * by all running kthreads that need to be subject to stuttering.
731 */ 721 */
732 bool stutter_wait(const char *title) 722 bool stutter_wait(const char *title)
733 { 723 {
>> 724 unsigned int i = 0;
734 bool ret = false; 725 bool ret = false;
735 ktime_t till_ns; !! 726 int spt;
736 727
737 cond_resched_tasks_rcu_qs(); 728 cond_resched_tasks_rcu_qs();
738 till_ns = READ_ONCE(stutter_till_abs_t !! 729 spt = READ_ONCE(stutter_pause_test);
739 if (till_ns && ktime_before(ktime_get( !! 730 for (; spt; spt = READ_ONCE(stutter_pause_test)) {
740 torture_hrtimeout_ns(till_ns, !! 731 if (!ret) {
741 ret = true; !! 732 sched_set_normal(current, MAX_NICE);
>> 733 ret = true;
>> 734 }
>> 735 if (spt == 1) {
>> 736 schedule_timeout_interruptible(1);
>> 737 } else if (spt == 2) {
>> 738 while (READ_ONCE(stutter_pause_test)) {
>> 739 if (!(i++ & 0xffff))
>> 740 torture_hrtimeout_us(10, 0, NULL);
>> 741 cond_resched();
>> 742 }
>> 743 } else {
>> 744 schedule_timeout_interruptible(round_jiffies_relative(HZ));
>> 745 }
>> 746 torture_shutdown_absorb(title);
742 } 747 }
743 torture_shutdown_absorb(title); <<
744 return ret; 748 return ret;
745 } 749 }
746 EXPORT_SYMBOL_GPL(stutter_wait); 750 EXPORT_SYMBOL_GPL(stutter_wait);
747 751
748 /* 752 /*
749 * Cause the torture test to "stutter", starti 753 * Cause the torture test to "stutter", starting and stopping all
750 * threads periodically. 754 * threads periodically.
751 */ 755 */
752 static int torture_stutter(void *arg) 756 static int torture_stutter(void *arg)
753 { 757 {
754 ktime_t till_ns; !! 758 DEFINE_TORTURE_RANDOM(rand);
>> 759 int wtime;
755 760
756 VERBOSE_TOROUT_STRING("torture_stutter 761 VERBOSE_TOROUT_STRING("torture_stutter task started");
757 do { 762 do {
758 if (!torture_must_stop() && st 763 if (!torture_must_stop() && stutter > 1) {
759 till_ns = ktime_add_ns !! 764 wtime = stutter;
760 !! 765 if (stutter > 2) {
761 WRITE_ONCE(stutter_til !! 766 WRITE_ONCE(stutter_pause_test, 1);
762 torture_hrtimeout_jiff !! 767 wtime = stutter - 3;
>> 768 torture_hrtimeout_jiffies(wtime, &rand);
>> 769 wtime = 2;
>> 770 }
>> 771 WRITE_ONCE(stutter_pause_test, 2);
>> 772 torture_hrtimeout_jiffies(wtime, NULL);
763 } 773 }
>> 774 WRITE_ONCE(stutter_pause_test, 0);
764 if (!torture_must_stop()) 775 if (!torture_must_stop())
765 torture_hrtimeout_jiff 776 torture_hrtimeout_jiffies(stutter_gap, NULL);
766 torture_shutdown_absorb("tortu 777 torture_shutdown_absorb("torture_stutter");
767 } while (!torture_must_stop()); 778 } while (!torture_must_stop());
768 torture_kthread_stopping("torture_stut 779 torture_kthread_stopping("torture_stutter");
769 return 0; 780 return 0;
770 } 781 }
771 782
772 /* 783 /*
773 * Initialize and kick off the torture_stutter 784 * Initialize and kick off the torture_stutter kthread.
774 */ 785 */
775 int torture_stutter_init(const int s, const in 786 int torture_stutter_init(const int s, const int sgap)
776 { 787 {
777 stutter = s; 788 stutter = s;
778 stutter_gap = sgap; 789 stutter_gap = sgap;
779 return torture_create_kthread(torture_ 790 return torture_create_kthread(torture_stutter, NULL, stutter_task);
780 } 791 }
781 EXPORT_SYMBOL_GPL(torture_stutter_init); 792 EXPORT_SYMBOL_GPL(torture_stutter_init);
782 793
783 /* 794 /*
784 * Cleanup after the torture_stutter kthread. 795 * Cleanup after the torture_stutter kthread.
785 */ 796 */
786 static void torture_stutter_cleanup(void) 797 static void torture_stutter_cleanup(void)
787 { 798 {
788 if (!stutter_task) 799 if (!stutter_task)
789 return; 800 return;
790 VERBOSE_TOROUT_STRING("Stopping tortur 801 VERBOSE_TOROUT_STRING("Stopping torture_stutter task");
791 kthread_stop(stutter_task); 802 kthread_stop(stutter_task);
792 stutter_task = NULL; 803 stutter_task = NULL;
793 } 804 }
794 805
795 static void <<
796 torture_print_module_parms(void) <<
797 { <<
798 pr_alert("torture module --- %s: disa <<
799 torture_type, disable_onoff_a <<
800 } <<
801 <<
802 /* 806 /*
803 * Initialize torture module. Please note tha 807 * Initialize torture module. Please note that this is -not- invoked via
804 * the usual module_init() mechanism, but rath 808 * the usual module_init() mechanism, but rather by an explicit call from
805 * the client torture module. This call must 809 * the client torture module. This call must be paired with a later
806 * torture_init_end(). 810 * torture_init_end().
807 * 811 *
808 * The runnable parameter points to a flag tha 812 * The runnable parameter points to a flag that controls whether or not
809 * the test is currently runnable. If there i 813 * the test is currently runnable. If there is no such flag, pass in NULL.
810 */ 814 */
811 bool torture_init_begin(char *ttype, int v) 815 bool torture_init_begin(char *ttype, int v)
812 { 816 {
813 mutex_lock(&fullstop_mutex); 817 mutex_lock(&fullstop_mutex);
814 if (torture_type != NULL) { 818 if (torture_type != NULL) {
815 pr_alert("%s: Refusing %s init 819 pr_alert("%s: Refusing %s init: %s running.\n",
816 __func__, ttype, tor 820 __func__, ttype, torture_type);
817 pr_alert("%s: One torture test 821 pr_alert("%s: One torture test at a time!\n", __func__);
818 mutex_unlock(&fullstop_mutex); 822 mutex_unlock(&fullstop_mutex);
819 return false; 823 return false;
820 } 824 }
821 torture_type = ttype; 825 torture_type = ttype;
822 verbose = v; 826 verbose = v;
823 fullstop = FULLSTOP_DONTSTOP; 827 fullstop = FULLSTOP_DONTSTOP;
824 torture_print_module_parms(); <<
825 return true; 828 return true;
826 } 829 }
827 EXPORT_SYMBOL_GPL(torture_init_begin); 830 EXPORT_SYMBOL_GPL(torture_init_begin);
828 831
829 /* 832 /*
830 * Tell the torture module that initialization 833 * Tell the torture module that initialization is complete.
831 */ 834 */
832 void torture_init_end(void) 835 void torture_init_end(void)
833 { 836 {
834 mutex_unlock(&fullstop_mutex); 837 mutex_unlock(&fullstop_mutex);
835 register_reboot_notifier(&torture_shut 838 register_reboot_notifier(&torture_shutdown_nb);
836 } 839 }
837 EXPORT_SYMBOL_GPL(torture_init_end); 840 EXPORT_SYMBOL_GPL(torture_init_end);
838 841
839 /* 842 /*
840 * Clean up torture module. Please note that 843 * Clean up torture module. Please note that this is -not- invoked via
841 * the usual module_exit() mechanism, but rath 844 * the usual module_exit() mechanism, but rather by an explicit call from
842 * the client torture module. Returns true if 845 * the client torture module. Returns true if a race with system shutdown
843 * is detected, otherwise, all kthreads starte 846 * is detected, otherwise, all kthreads started by functions in this file
844 * will be shut down. 847 * will be shut down.
845 * 848 *
846 * This must be called before the caller start 849 * This must be called before the caller starts shutting down its own
847 * kthreads. 850 * kthreads.
848 * 851 *
849 * Both torture_cleanup_begin() and torture_cl 852 * Both torture_cleanup_begin() and torture_cleanup_end() must be paired,
850 * in order to correctly perform the cleanup. 853 * in order to correctly perform the cleanup. They are separated because
851 * threads can still need to reference the tor 854 * threads can still need to reference the torture_type type, thus nullify
852 * only after completing all other relevant ca 855 * only after completing all other relevant calls.
853 */ 856 */
854 bool torture_cleanup_begin(void) 857 bool torture_cleanup_begin(void)
855 { 858 {
856 mutex_lock(&fullstop_mutex); 859 mutex_lock(&fullstop_mutex);
857 if (READ_ONCE(fullstop) == FULLSTOP_SH 860 if (READ_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
858 pr_warn("Concurrent rmmod and 861 pr_warn("Concurrent rmmod and shutdown illegal!\n");
859 mutex_unlock(&fullstop_mutex); 862 mutex_unlock(&fullstop_mutex);
860 schedule_timeout_uninterruptib 863 schedule_timeout_uninterruptible(10);
861 return true; 864 return true;
862 } 865 }
863 WRITE_ONCE(fullstop, FULLSTOP_RMMOD); 866 WRITE_ONCE(fullstop, FULLSTOP_RMMOD);
864 mutex_unlock(&fullstop_mutex); 867 mutex_unlock(&fullstop_mutex);
865 torture_shutdown_cleanup(); 868 torture_shutdown_cleanup();
866 torture_shuffle_cleanup(); 869 torture_shuffle_cleanup();
867 torture_stutter_cleanup(); 870 torture_stutter_cleanup();
868 torture_onoff_cleanup(); 871 torture_onoff_cleanup();
869 return false; 872 return false;
870 } 873 }
871 EXPORT_SYMBOL_GPL(torture_cleanup_begin); 874 EXPORT_SYMBOL_GPL(torture_cleanup_begin);
872 875
873 void torture_cleanup_end(void) 876 void torture_cleanup_end(void)
874 { 877 {
875 mutex_lock(&fullstop_mutex); 878 mutex_lock(&fullstop_mutex);
876 torture_type = NULL; 879 torture_type = NULL;
877 mutex_unlock(&fullstop_mutex); 880 mutex_unlock(&fullstop_mutex);
878 } 881 }
879 EXPORT_SYMBOL_GPL(torture_cleanup_end); 882 EXPORT_SYMBOL_GPL(torture_cleanup_end);
880 883
881 /* 884 /*
882 * Is it time for the current torture test to 885 * Is it time for the current torture test to stop?
883 */ 886 */
884 bool torture_must_stop(void) 887 bool torture_must_stop(void)
885 { 888 {
886 return torture_must_stop_irq() || kthr 889 return torture_must_stop_irq() || kthread_should_stop();
887 } 890 }
888 EXPORT_SYMBOL_GPL(torture_must_stop); 891 EXPORT_SYMBOL_GPL(torture_must_stop);
889 892
890 /* 893 /*
891 * Is it time for the current torture test to 894 * Is it time for the current torture test to stop? This is the irq-safe
892 * version, hence no check for kthread_should_ 895 * version, hence no check for kthread_should_stop().
893 */ 896 */
894 bool torture_must_stop_irq(void) 897 bool torture_must_stop_irq(void)
895 { 898 {
896 return READ_ONCE(fullstop) != FULLSTOP 899 return READ_ONCE(fullstop) != FULLSTOP_DONTSTOP;
897 } 900 }
898 EXPORT_SYMBOL_GPL(torture_must_stop_irq); 901 EXPORT_SYMBOL_GPL(torture_must_stop_irq);
899 902
900 /* 903 /*
901 * Each kthread must wait for kthread_should_s 904 * Each kthread must wait for kthread_should_stop() before returning from
902 * its top-level function, otherwise segfaults 905 * its top-level function, otherwise segfaults ensue. This function
903 * prints a "stopping" message and waits for k 906 * prints a "stopping" message and waits for kthread_should_stop(), and
904 * should be called from all torture kthreads 907 * should be called from all torture kthreads immediately prior to
905 * returning. 908 * returning.
906 */ 909 */
907 void torture_kthread_stopping(char *title) 910 void torture_kthread_stopping(char *title)
908 { 911 {
909 char buf[128]; 912 char buf[128];
910 913
911 snprintf(buf, sizeof(buf), "%s is stop 914 snprintf(buf, sizeof(buf), "%s is stopping", title);
912 VERBOSE_TOROUT_STRING(buf); 915 VERBOSE_TOROUT_STRING(buf);
913 while (!kthread_should_stop()) { 916 while (!kthread_should_stop()) {
914 torture_shutdown_absorb(title) 917 torture_shutdown_absorb(title);
915 schedule_timeout_uninterruptib 918 schedule_timeout_uninterruptible(HZ / 20);
916 } 919 }
917 } 920 }
918 EXPORT_SYMBOL_GPL(torture_kthread_stopping); 921 EXPORT_SYMBOL_GPL(torture_kthread_stopping);
919 922
920 /* 923 /*
921 * Create a generic torture kthread that is im 924 * Create a generic torture kthread that is immediately runnable. If you
922 * need the kthread to be stopped so that you 925 * need the kthread to be stopped so that you can do something to it before
923 * it starts, you will need to open-code your 926 * it starts, you will need to open-code your own.
924 */ 927 */
925 int _torture_create_kthread(int (*fn)(void *ar 928 int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
926 char *f, struct ta !! 929 char *f, struct task_struct **tp)
927 { 930 {
928 int ret = 0; 931 int ret = 0;
929 932
930 VERBOSE_TOROUT_STRING(m); 933 VERBOSE_TOROUT_STRING(m);
931 *tp = kthread_create(fn, arg, "%s", s) 934 *tp = kthread_create(fn, arg, "%s", s);
932 if (IS_ERR(*tp)) { 935 if (IS_ERR(*tp)) {
933 ret = PTR_ERR(*tp); 936 ret = PTR_ERR(*tp);
934 TOROUT_ERRSTRING(f); 937 TOROUT_ERRSTRING(f);
935 *tp = NULL; 938 *tp = NULL;
936 return ret; 939 return ret;
937 } 940 }
938 <<
939 if (cbf) <<
940 cbf(*tp); <<
941 <<
942 wake_up_process(*tp); // Process is s 941 wake_up_process(*tp); // Process is sleeping, so ordering provided.
943 torture_shuffle_task_register(*tp); 942 torture_shuffle_task_register(*tp);
944 return ret; 943 return ret;
945 } 944 }
946 EXPORT_SYMBOL_GPL(_torture_create_kthread); 945 EXPORT_SYMBOL_GPL(_torture_create_kthread);
947 946
948 /* 947 /*
949 * Stop a generic kthread, emitting a message. 948 * Stop a generic kthread, emitting a message.
950 */ 949 */
951 void _torture_stop_kthread(char *m, struct tas 950 void _torture_stop_kthread(char *m, struct task_struct **tp)
952 { 951 {
953 if (*tp == NULL) 952 if (*tp == NULL)
954 return; 953 return;
955 VERBOSE_TOROUT_STRING(m); 954 VERBOSE_TOROUT_STRING(m);
956 kthread_stop(*tp); 955 kthread_stop(*tp);
957 *tp = NULL; 956 *tp = NULL;
958 } 957 }
959 EXPORT_SYMBOL_GPL(_torture_stop_kthread); 958 EXPORT_SYMBOL_GPL(_torture_stop_kthread);
960 959
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