1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Torture test for smp_call_function() and friends.
4 //
5 // Copyright (C) Facebook, 2020.
6 //
7 // Author: Paul E. McKenney <paulmck@kernel.org>
8
9 #define pr_fmt(fmt) fmt
10
11 #include <linux/atomic.h>
12 #include <linux/bitops.h>
13 #include <linux/completion.h>
14 #include <linux/cpu.h>
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/init.h>
18 #include <linux/interrupt.h>
19 #include <linux/kthread.h>
20 #include <linux/kernel.h>
21 #include <linux/mm.h>
22 #include <linux/module.h>
23 #include <linux/moduleparam.h>
24 #include <linux/notifier.h>
25 #include <linux/percpu.h>
26 #include <linux/rcupdate.h>
27 #include <linux/rcupdate_trace.h>
28 #include <linux/reboot.h>
29 #include <linux/sched.h>
30 #include <linux/spinlock.h>
31 #include <linux/smp.h>
32 #include <linux/stat.h>
33 #include <linux/srcu.h>
34 #include <linux/slab.h>
35 #include <linux/torture.h>
36 #include <linux/types.h>
37
38 #define SCFTORT_STRING "scftorture"
39 #define SCFTORT_FLAG SCFTORT_STRING ": "
40
41 #define VERBOSE_SCFTORTOUT(s, x...) \
42 do { if (verbose) pr_alert(SCFTORT_FLAG s "\n", ## x); } while (0)
43
44 #define SCFTORTOUT_ERRSTRING(s, x...) pr_alert(SCFTORT_FLAG "!!! " s "\n", ## x)
45
46 MODULE_DESCRIPTION("Torture tests on the smp_call_function() family of primitives");
47 MODULE_LICENSE("GPL");
48 MODULE_AUTHOR("Paul E. McKenney <paulmck@kernel.org>");
49
50 // Wait until there are multiple CPUs before starting test.
51 torture_param(int, holdoff, IS_BUILTIN(CONFIG_SCF_TORTURE_TEST) ? 10 : 0,
52 "Holdoff time before test start (s)");
53 torture_param(int, longwait, 0, "Include ridiculously long waits? (seconds)");
54 torture_param(int, nthreads, -1, "# threads, defaults to -1 for all CPUs.");
55 torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
56 torture_param(int, onoff_interval, 0, "Time between CPU hotplugs (s), 0=disable");
57 torture_param(int, shutdown_secs, 0, "Shutdown time (ms), <= zero to disable.");
58 torture_param(int, stat_interval, 60, "Number of seconds between stats printk()s.");
59 torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable");
60 torture_param(bool, use_cpus_read_lock, 0, "Use cpus_read_lock() to exclude CPU hotplug.");
61 torture_param(int, verbose, 0, "Enable verbose debugging printk()s");
62 torture_param(int, weight_resched, -1, "Testing weight for resched_cpu() operations.");
63 torture_param(int, weight_single, -1, "Testing weight for single-CPU no-wait operations.");
64 torture_param(int, weight_single_rpc, -1, "Testing weight for single-CPU RPC operations.");
65 torture_param(int, weight_single_wait, -1, "Testing weight for single-CPU operations.");
66 torture_param(int, weight_many, -1, "Testing weight for multi-CPU no-wait operations.");
67 torture_param(int, weight_many_wait, -1, "Testing weight for multi-CPU operations.");
68 torture_param(int, weight_all, -1, "Testing weight for all-CPU no-wait operations.");
69 torture_param(int, weight_all_wait, -1, "Testing weight for all-CPU operations.");
70
71 static char *torture_type = "";
72
73 #ifdef MODULE
74 # define SCFTORT_SHUTDOWN 0
75 #else
76 # define SCFTORT_SHUTDOWN 1
77 #endif
78
79 torture_param(bool, shutdown, SCFTORT_SHUTDOWN, "Shutdown at end of torture test.");
80
81 struct scf_statistics {
82 struct task_struct *task;
83 int cpu;
84 long long n_resched;
85 long long n_single;
86 long long n_single_ofl;
87 long long n_single_rpc;
88 long long n_single_rpc_ofl;
89 long long n_single_wait;
90 long long n_single_wait_ofl;
91 long long n_many;
92 long long n_many_wait;
93 long long n_all;
94 long long n_all_wait;
95 };
96
97 static struct scf_statistics *scf_stats_p;
98 static struct task_struct *scf_torture_stats_task;
99 static DEFINE_PER_CPU(long long, scf_invoked_count);
100
101 // Data for random primitive selection
102 #define SCF_PRIM_RESCHED 0
103 #define SCF_PRIM_SINGLE 1
104 #define SCF_PRIM_SINGLE_RPC 2
105 #define SCF_PRIM_MANY 3
106 #define SCF_PRIM_ALL 4
107 #define SCF_NPRIMS 8 // Need wait and no-wait versions of each,
108 // except for SCF_PRIM_RESCHED and
109 // SCF_PRIM_SINGLE_RPC.
110
111 static char *scf_prim_name[] = {
112 "resched_cpu",
113 "smp_call_function_single",
114 "smp_call_function_single_rpc",
115 "smp_call_function_many",
116 "smp_call_function",
117 };
118
119 struct scf_selector {
120 unsigned long scfs_weight;
121 int scfs_prim;
122 bool scfs_wait;
123 };
124 static struct scf_selector scf_sel_array[SCF_NPRIMS];
125 static int scf_sel_array_len;
126 static unsigned long scf_sel_totweight;
127
128 // Communicate between caller and handler.
129 struct scf_check {
130 bool scfc_in;
131 bool scfc_out;
132 int scfc_cpu; // -1 for not _single().
133 bool scfc_wait;
134 bool scfc_rpc;
135 struct completion scfc_completion;
136 };
137
138 // Use to wait for all threads to start.
139 static atomic_t n_started;
140 static atomic_t n_errs;
141 static atomic_t n_mb_in_errs;
142 static atomic_t n_mb_out_errs;
143 static atomic_t n_alloc_errs;
144 static bool scfdone;
145 static char *bangstr = "";
146
147 static DEFINE_TORTURE_RANDOM_PERCPU(scf_torture_rand);
148
149 extern void resched_cpu(int cpu); // An alternative IPI vector.
150
151 // Print torture statistics. Caller must ensure serialization.
152 static void scf_torture_stats_print(void)
153 {
154 int cpu;
155 int i;
156 long long invoked_count = 0;
157 bool isdone = READ_ONCE(scfdone);
158 struct scf_statistics scfs = {};
159
160 for_each_possible_cpu(cpu)
161 invoked_count += data_race(per_cpu(scf_invoked_count, cpu));
162 for (i = 0; i < nthreads; i++) {
163 scfs.n_resched += scf_stats_p[i].n_resched;
164 scfs.n_single += scf_stats_p[i].n_single;
165 scfs.n_single_ofl += scf_stats_p[i].n_single_ofl;
166 scfs.n_single_rpc += scf_stats_p[i].n_single_rpc;
167 scfs.n_single_wait += scf_stats_p[i].n_single_wait;
168 scfs.n_single_wait_ofl += scf_stats_p[i].n_single_wait_ofl;
169 scfs.n_many += scf_stats_p[i].n_many;
170 scfs.n_many_wait += scf_stats_p[i].n_many_wait;
171 scfs.n_all += scf_stats_p[i].n_all;
172 scfs.n_all_wait += scf_stats_p[i].n_all_wait;
173 }
174 if (atomic_read(&n_errs) || atomic_read(&n_mb_in_errs) ||
175 atomic_read(&n_mb_out_errs) ||
176 (!IS_ENABLED(CONFIG_KASAN) && atomic_read(&n_alloc_errs)))
177 bangstr = "!!! ";
178 pr_alert("%s %sscf_invoked_count %s: %lld resched: %lld single: %lld/%lld single_ofl: %lld/%lld single_rpc: %lld single_rpc_ofl: %lld many: %lld/%lld all: %lld/%lld ",
179 SCFTORT_FLAG, bangstr, isdone ? "VER" : "ver", invoked_count, scfs.n_resched,
180 scfs.n_single, scfs.n_single_wait, scfs.n_single_ofl, scfs.n_single_wait_ofl,
181 scfs.n_single_rpc, scfs.n_single_rpc_ofl,
182 scfs.n_many, scfs.n_many_wait, scfs.n_all, scfs.n_all_wait);
183 torture_onoff_stats();
184 pr_cont("ste: %d stnmie: %d stnmoe: %d staf: %d\n", atomic_read(&n_errs),
185 atomic_read(&n_mb_in_errs), atomic_read(&n_mb_out_errs),
186 atomic_read(&n_alloc_errs));
187 }
188
189 // Periodically prints torture statistics, if periodic statistics printing
190 // was specified via the stat_interval module parameter.
191 static int
192 scf_torture_stats(void *arg)
193 {
194 VERBOSE_TOROUT_STRING("scf_torture_stats task started");
195 do {
196 schedule_timeout_interruptible(stat_interval * HZ);
197 scf_torture_stats_print();
198 torture_shutdown_absorb("scf_torture_stats");
199 } while (!torture_must_stop());
200 torture_kthread_stopping("scf_torture_stats");
201 return 0;
202 }
203
204 // Add a primitive to the scf_sel_array[].
205 static void scf_sel_add(unsigned long weight, int prim, bool wait)
206 {
207 struct scf_selector *scfsp = &scf_sel_array[scf_sel_array_len];
208
209 // If no weight, if array would overflow, if computing three-place
210 // percentages would overflow, or if the scf_prim_name[] array would
211 // overflow, don't bother. In the last three two cases, complain.
212 if (!weight ||
213 WARN_ON_ONCE(scf_sel_array_len >= ARRAY_SIZE(scf_sel_array)) ||
214 WARN_ON_ONCE(0 - 100000 * weight <= 100000 * scf_sel_totweight) ||
215 WARN_ON_ONCE(prim >= ARRAY_SIZE(scf_prim_name)))
216 return;
217 scf_sel_totweight += weight;
218 scfsp->scfs_weight = scf_sel_totweight;
219 scfsp->scfs_prim = prim;
220 scfsp->scfs_wait = wait;
221 scf_sel_array_len++;
222 }
223
224 // Dump out weighting percentages for scf_prim_name[] array.
225 static void scf_sel_dump(void)
226 {
227 int i;
228 unsigned long oldw = 0;
229 struct scf_selector *scfsp;
230 unsigned long w;
231
232 for (i = 0; i < scf_sel_array_len; i++) {
233 scfsp = &scf_sel_array[i];
234 w = (scfsp->scfs_weight - oldw) * 100000 / scf_sel_totweight;
235 pr_info("%s: %3lu.%03lu %s(%s)\n", __func__, w / 1000, w % 1000,
236 scf_prim_name[scfsp->scfs_prim],
237 scfsp->scfs_wait ? "wait" : "nowait");
238 oldw = scfsp->scfs_weight;
239 }
240 }
241
242 // Randomly pick a primitive and wait/nowait, based on weightings.
243 static struct scf_selector *scf_sel_rand(struct torture_random_state *trsp)
244 {
245 int i;
246 unsigned long w = torture_random(trsp) % (scf_sel_totweight + 1);
247
248 for (i = 0; i < scf_sel_array_len; i++)
249 if (scf_sel_array[i].scfs_weight >= w)
250 return &scf_sel_array[i];
251 WARN_ON_ONCE(1);
252 return &scf_sel_array[0];
253 }
254
255 // Update statistics and occasionally burn up mass quantities of CPU time,
256 // if told to do so via scftorture.longwait. Otherwise, occasionally burn
257 // a little bit.
258 static void scf_handler(void *scfc_in)
259 {
260 int i;
261 int j;
262 unsigned long r = torture_random(this_cpu_ptr(&scf_torture_rand));
263 struct scf_check *scfcp = scfc_in;
264
265 if (likely(scfcp)) {
266 WRITE_ONCE(scfcp->scfc_out, false); // For multiple receivers.
267 if (WARN_ON_ONCE(unlikely(!READ_ONCE(scfcp->scfc_in))))
268 atomic_inc(&n_mb_in_errs);
269 }
270 this_cpu_inc(scf_invoked_count);
271 if (longwait <= 0) {
272 if (!(r & 0xffc0)) {
273 udelay(r & 0x3f);
274 goto out;
275 }
276 }
277 if (r & 0xfff)
278 goto out;
279 r = (r >> 12);
280 if (longwait <= 0) {
281 udelay((r & 0xff) + 1);
282 goto out;
283 }
284 r = r % longwait + 1;
285 for (i = 0; i < r; i++) {
286 for (j = 0; j < 1000; j++) {
287 udelay(1000);
288 cpu_relax();
289 }
290 }
291 out:
292 if (unlikely(!scfcp))
293 return;
294 if (scfcp->scfc_wait) {
295 WRITE_ONCE(scfcp->scfc_out, true);
296 if (scfcp->scfc_rpc)
297 complete(&scfcp->scfc_completion);
298 } else {
299 kfree(scfcp);
300 }
301 }
302
303 // As above, but check for correct CPU.
304 static void scf_handler_1(void *scfc_in)
305 {
306 struct scf_check *scfcp = scfc_in;
307
308 if (likely(scfcp) && WARN_ONCE(smp_processor_id() != scfcp->scfc_cpu, "%s: Wanted CPU %d got CPU %d\n", __func__, scfcp->scfc_cpu, smp_processor_id())) {
309 atomic_inc(&n_errs);
310 }
311 scf_handler(scfcp);
312 }
313
314 // Randomly do an smp_call_function*() invocation.
315 static void scftorture_invoke_one(struct scf_statistics *scfp, struct torture_random_state *trsp)
316 {
317 bool allocfail = false;
318 uintptr_t cpu;
319 int ret = 0;
320 struct scf_check *scfcp = NULL;
321 struct scf_selector *scfsp = scf_sel_rand(trsp);
322
323 if (use_cpus_read_lock)
324 cpus_read_lock();
325 else
326 preempt_disable();
327 if (scfsp->scfs_prim == SCF_PRIM_SINGLE || scfsp->scfs_wait) {
328 scfcp = kmalloc(sizeof(*scfcp), GFP_ATOMIC);
329 if (!scfcp) {
330 WARN_ON_ONCE(!IS_ENABLED(CONFIG_KASAN));
331 atomic_inc(&n_alloc_errs);
332 allocfail = true;
333 } else {
334 scfcp->scfc_cpu = -1;
335 scfcp->scfc_wait = scfsp->scfs_wait;
336 scfcp->scfc_out = false;
337 scfcp->scfc_rpc = false;
338 }
339 }
340 switch (scfsp->scfs_prim) {
341 case SCF_PRIM_RESCHED:
342 if (IS_BUILTIN(CONFIG_SCF_TORTURE_TEST)) {
343 cpu = torture_random(trsp) % nr_cpu_ids;
344 scfp->n_resched++;
345 resched_cpu(cpu);
346 this_cpu_inc(scf_invoked_count);
347 }
348 break;
349 case SCF_PRIM_SINGLE:
350 cpu = torture_random(trsp) % nr_cpu_ids;
351 if (scfsp->scfs_wait)
352 scfp->n_single_wait++;
353 else
354 scfp->n_single++;
355 if (scfcp) {
356 scfcp->scfc_cpu = cpu;
357 barrier(); // Prevent race-reduction compiler optimizations.
358 scfcp->scfc_in = true;
359 }
360 ret = smp_call_function_single(cpu, scf_handler_1, (void *)scfcp, scfsp->scfs_wait);
361 if (ret) {
362 if (scfsp->scfs_wait)
363 scfp->n_single_wait_ofl++;
364 else
365 scfp->n_single_ofl++;
366 kfree(scfcp);
367 scfcp = NULL;
368 }
369 break;
370 case SCF_PRIM_SINGLE_RPC:
371 if (!scfcp)
372 break;
373 cpu = torture_random(trsp) % nr_cpu_ids;
374 scfp->n_single_rpc++;
375 scfcp->scfc_cpu = cpu;
376 scfcp->scfc_wait = true;
377 init_completion(&scfcp->scfc_completion);
378 scfcp->scfc_rpc = true;
379 barrier(); // Prevent race-reduction compiler optimizations.
380 scfcp->scfc_in = true;
381 ret = smp_call_function_single(cpu, scf_handler_1, (void *)scfcp, 0);
382 if (!ret) {
383 if (use_cpus_read_lock)
384 cpus_read_unlock();
385 else
386 preempt_enable();
387 wait_for_completion(&scfcp->scfc_completion);
388 if (use_cpus_read_lock)
389 cpus_read_lock();
390 else
391 preempt_disable();
392 } else {
393 scfp->n_single_rpc_ofl++;
394 kfree(scfcp);
395 scfcp = NULL;
396 }
397 break;
398 case SCF_PRIM_MANY:
399 if (scfsp->scfs_wait)
400 scfp->n_many_wait++;
401 else
402 scfp->n_many++;
403 if (scfcp) {
404 barrier(); // Prevent race-reduction compiler optimizations.
405 scfcp->scfc_in = true;
406 }
407 smp_call_function_many(cpu_online_mask, scf_handler, scfcp, scfsp->scfs_wait);
408 break;
409 case SCF_PRIM_ALL:
410 if (scfsp->scfs_wait)
411 scfp->n_all_wait++;
412 else
413 scfp->n_all++;
414 if (scfcp) {
415 barrier(); // Prevent race-reduction compiler optimizations.
416 scfcp->scfc_in = true;
417 }
418 smp_call_function(scf_handler, scfcp, scfsp->scfs_wait);
419 break;
420 default:
421 WARN_ON_ONCE(1);
422 if (scfcp)
423 scfcp->scfc_out = true;
424 }
425 if (scfcp && scfsp->scfs_wait) {
426 if (WARN_ON_ONCE((num_online_cpus() > 1 || scfsp->scfs_prim == SCF_PRIM_SINGLE) &&
427 !scfcp->scfc_out)) {
428 pr_warn("%s: Memory-ordering failure, scfs_prim: %d.\n", __func__, scfsp->scfs_prim);
429 atomic_inc(&n_mb_out_errs); // Leak rather than trash!
430 } else {
431 kfree(scfcp);
432 }
433 barrier(); // Prevent race-reduction compiler optimizations.
434 }
435 if (use_cpus_read_lock)
436 cpus_read_unlock();
437 else
438 preempt_enable();
439 if (allocfail)
440 schedule_timeout_idle((1 + longwait) * HZ); // Let no-wait handlers complete.
441 else if (!(torture_random(trsp) & 0xfff))
442 schedule_timeout_uninterruptible(1);
443 }
444
445 // SCF test kthread. Repeatedly does calls to members of the
446 // smp_call_function() family of functions.
447 static int scftorture_invoker(void *arg)
448 {
449 int cpu;
450 int curcpu;
451 DEFINE_TORTURE_RANDOM(rand);
452 struct scf_statistics *scfp = (struct scf_statistics *)arg;
453 bool was_offline = false;
454
455 VERBOSE_SCFTORTOUT("scftorture_invoker %d: task started", scfp->cpu);
456 cpu = scfp->cpu % nr_cpu_ids;
457 WARN_ON_ONCE(set_cpus_allowed_ptr(current, cpumask_of(cpu)));
458 set_user_nice(current, MAX_NICE);
459 if (holdoff)
460 schedule_timeout_interruptible(holdoff * HZ);
461
462 VERBOSE_SCFTORTOUT("scftorture_invoker %d: Waiting for all SCF torturers from cpu %d", scfp->cpu, raw_smp_processor_id());
463
464 // Make sure that the CPU is affinitized appropriately during testing.
465 curcpu = raw_smp_processor_id();
466 WARN_ONCE(curcpu != scfp->cpu % nr_cpu_ids,
467 "%s: Wanted CPU %d, running on %d, nr_cpu_ids = %d\n",
468 __func__, scfp->cpu, curcpu, nr_cpu_ids);
469
470 if (!atomic_dec_return(&n_started))
471 while (atomic_read_acquire(&n_started)) {
472 if (torture_must_stop()) {
473 VERBOSE_SCFTORTOUT("scftorture_invoker %d ended before starting", scfp->cpu);
474 goto end;
475 }
476 schedule_timeout_uninterruptible(1);
477 }
478
479 VERBOSE_SCFTORTOUT("scftorture_invoker %d started", scfp->cpu);
480
481 do {
482 scftorture_invoke_one(scfp, &rand);
483 while (cpu_is_offline(cpu) && !torture_must_stop()) {
484 schedule_timeout_interruptible(HZ / 5);
485 was_offline = true;
486 }
487 if (was_offline) {
488 set_cpus_allowed_ptr(current, cpumask_of(cpu));
489 was_offline = false;
490 }
491 cond_resched();
492 stutter_wait("scftorture_invoker");
493 } while (!torture_must_stop());
494
495 VERBOSE_SCFTORTOUT("scftorture_invoker %d ended", scfp->cpu);
496 end:
497 torture_kthread_stopping("scftorture_invoker");
498 return 0;
499 }
500
501 static void
502 scftorture_print_module_parms(const char *tag)
503 {
504 pr_alert(SCFTORT_FLAG
505 "--- %s: verbose=%d holdoff=%d longwait=%d nthreads=%d onoff_holdoff=%d onoff_interval=%d shutdown_secs=%d stat_interval=%d stutter=%d use_cpus_read_lock=%d, weight_resched=%d, weight_single=%d, weight_single_rpc=%d, weight_single_wait=%d, weight_many=%d, weight_many_wait=%d, weight_all=%d, weight_all_wait=%d\n", tag,
506 verbose, holdoff, longwait, nthreads, onoff_holdoff, onoff_interval, shutdown, stat_interval, stutter, use_cpus_read_lock, weight_resched, weight_single, weight_single_rpc, weight_single_wait, weight_many, weight_many_wait, weight_all, weight_all_wait);
507 }
508
509 static void scf_cleanup_handler(void *unused)
510 {
511 }
512
513 static void scf_torture_cleanup(void)
514 {
515 int i;
516
517 if (torture_cleanup_begin())
518 return;
519
520 WRITE_ONCE(scfdone, true);
521 if (nthreads && scf_stats_p)
522 for (i = 0; i < nthreads; i++)
523 torture_stop_kthread("scftorture_invoker", scf_stats_p[i].task);
524 else
525 goto end;
526 smp_call_function(scf_cleanup_handler, NULL, 0);
527 torture_stop_kthread(scf_torture_stats, scf_torture_stats_task);
528 scf_torture_stats_print(); // -After- the stats thread is stopped!
529 kfree(scf_stats_p); // -After- the last stats print has completed!
530 scf_stats_p = NULL;
531
532 if (atomic_read(&n_errs) || atomic_read(&n_mb_in_errs) || atomic_read(&n_mb_out_errs))
533 scftorture_print_module_parms("End of test: FAILURE");
534 else if (torture_onoff_failures())
535 scftorture_print_module_parms("End of test: LOCK_HOTPLUG");
536 else
537 scftorture_print_module_parms("End of test: SUCCESS");
538
539 end:
540 torture_cleanup_end();
541 }
542
543 static int __init scf_torture_init(void)
544 {
545 long i;
546 int firsterr = 0;
547 unsigned long weight_resched1 = weight_resched;
548 unsigned long weight_single1 = weight_single;
549 unsigned long weight_single_rpc1 = weight_single_rpc;
550 unsigned long weight_single_wait1 = weight_single_wait;
551 unsigned long weight_many1 = weight_many;
552 unsigned long weight_many_wait1 = weight_many_wait;
553 unsigned long weight_all1 = weight_all;
554 unsigned long weight_all_wait1 = weight_all_wait;
555
556 if (!torture_init_begin(SCFTORT_STRING, verbose))
557 return -EBUSY;
558
559 scftorture_print_module_parms("Start of test");
560
561 if (weight_resched <= 0 &&
562 weight_single <= 0 && weight_single_rpc <= 0 && weight_single_wait <= 0 &&
563 weight_many <= 0 && weight_many_wait <= 0 &&
564 weight_all <= 0 && weight_all_wait <= 0) {
565 weight_resched1 = weight_resched == 0 ? 0 : 2 * nr_cpu_ids;
566 weight_single1 = weight_single == 0 ? 0 : 2 * nr_cpu_ids;
567 weight_single_rpc1 = weight_single_rpc == 0 ? 0 : 2 * nr_cpu_ids;
568 weight_single_wait1 = weight_single_wait == 0 ? 0 : 2 * nr_cpu_ids;
569 weight_many1 = weight_many == 0 ? 0 : 2;
570 weight_many_wait1 = weight_many_wait == 0 ? 0 : 2;
571 weight_all1 = weight_all == 0 ? 0 : 1;
572 weight_all_wait1 = weight_all_wait == 0 ? 0 : 1;
573 } else {
574 if (weight_resched == -1)
575 weight_resched1 = 0;
576 if (weight_single == -1)
577 weight_single1 = 0;
578 if (weight_single_rpc == -1)
579 weight_single_rpc1 = 0;
580 if (weight_single_wait == -1)
581 weight_single_wait1 = 0;
582 if (weight_many == -1)
583 weight_many1 = 0;
584 if (weight_many_wait == -1)
585 weight_many_wait1 = 0;
586 if (weight_all == -1)
587 weight_all1 = 0;
588 if (weight_all_wait == -1)
589 weight_all_wait1 = 0;
590 }
591 if (weight_resched1 == 0 && weight_single1 == 0 && weight_single_rpc1 == 0 &&
592 weight_single_wait1 == 0 && weight_many1 == 0 && weight_many_wait1 == 0 &&
593 weight_all1 == 0 && weight_all_wait1 == 0) {
594 SCFTORTOUT_ERRSTRING("all zero weights makes no sense");
595 firsterr = -EINVAL;
596 goto unwind;
597 }
598 if (IS_BUILTIN(CONFIG_SCF_TORTURE_TEST))
599 scf_sel_add(weight_resched1, SCF_PRIM_RESCHED, false);
600 else if (weight_resched1)
601 SCFTORTOUT_ERRSTRING("built as module, weight_resched ignored");
602 scf_sel_add(weight_single1, SCF_PRIM_SINGLE, false);
603 scf_sel_add(weight_single_rpc1, SCF_PRIM_SINGLE_RPC, true);
604 scf_sel_add(weight_single_wait1, SCF_PRIM_SINGLE, true);
605 scf_sel_add(weight_many1, SCF_PRIM_MANY, false);
606 scf_sel_add(weight_many_wait1, SCF_PRIM_MANY, true);
607 scf_sel_add(weight_all1, SCF_PRIM_ALL, false);
608 scf_sel_add(weight_all_wait1, SCF_PRIM_ALL, true);
609 scf_sel_dump();
610
611 if (onoff_interval > 0) {
612 firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval, NULL);
613 if (torture_init_error(firsterr))
614 goto unwind;
615 }
616 if (shutdown_secs > 0) {
617 firsterr = torture_shutdown_init(shutdown_secs, scf_torture_cleanup);
618 if (torture_init_error(firsterr))
619 goto unwind;
620 }
621 if (stutter > 0) {
622 firsterr = torture_stutter_init(stutter, stutter);
623 if (torture_init_error(firsterr))
624 goto unwind;
625 }
626
627 // Worker tasks invoking smp_call_function().
628 if (nthreads < 0)
629 nthreads = num_online_cpus();
630 scf_stats_p = kcalloc(nthreads, sizeof(scf_stats_p[0]), GFP_KERNEL);
631 if (!scf_stats_p) {
632 SCFTORTOUT_ERRSTRING("out of memory");
633 firsterr = -ENOMEM;
634 goto unwind;
635 }
636
637 VERBOSE_SCFTORTOUT("Starting %d smp_call_function() threads", nthreads);
638
639 atomic_set(&n_started, nthreads);
640 for (i = 0; i < nthreads; i++) {
641 scf_stats_p[i].cpu = i;
642 firsterr = torture_create_kthread(scftorture_invoker, (void *)&scf_stats_p[i],
643 scf_stats_p[i].task);
644 if (torture_init_error(firsterr))
645 goto unwind;
646 }
647 if (stat_interval > 0) {
648 firsterr = torture_create_kthread(scf_torture_stats, NULL, scf_torture_stats_task);
649 if (torture_init_error(firsterr))
650 goto unwind;
651 }
652
653 torture_init_end();
654 return 0;
655
656 unwind:
657 torture_init_end();
658 scf_torture_cleanup();
659 if (shutdown_secs) {
660 WARN_ON(!IS_MODULE(CONFIG_SCF_TORTURE_TEST));
661 kernel_power_off();
662 }
663 return firsterr;
664 }
665
666 module_init(scf_torture_init);
667 module_exit(scf_torture_cleanup);
668
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