1 // SPDX-License-Identifier: GPL-2.0+
3 * Module-based torture test facility for locking
5 * Copyright (C) IBM Corporation, 2014
7 * Authors: Paul E. McKenney <paulmck@linux.ibm.com>
8 * Davidlohr Bueso <dave@stgolabs.net>
9 * Based on kernel/rcu/torture.c.
12 #define pr_fmt(fmt) fmt
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/kthread.h>
17 #include <linux/sched/rt.h>
18 #include <linux/spinlock.h>
19 #include <linux/mutex.h>
20 #include <linux/rwsem.h>
21 #include <linux/smp.h>
22 #include <linux/interrupt.h>
23 #include <linux/sched.h>
24 #include <uapi/linux/sched/types.h>
25 #include <linux/rtmutex.h>
26 #include <linux/atomic.h>
27 #include <linux/moduleparam.h>
28 #include <linux/delay.h>
29 #include <linux/slab.h>
30 #include <linux/torture.h>
31 #include <linux/reboot.h>
33 MODULE_LICENSE("GPL");
34 MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");
36 torture_param(int, nwriters_stress
, -1,
37 "Number of write-locking stress-test threads");
38 torture_param(int, nreaders_stress
, -1,
39 "Number of read-locking stress-test threads");
40 torture_param(int, onoff_holdoff
, 0, "Time after boot before CPU hotplugs (s)");
41 torture_param(int, onoff_interval
, 0,
42 "Time between CPU hotplugs (s), 0=disable");
43 torture_param(int, shuffle_interval
, 3,
44 "Number of jiffies between shuffles, 0=disable");
45 torture_param(int, shutdown_secs
, 0, "Shutdown time (j), <= zero to disable.");
46 torture_param(int, stat_interval
, 60,
47 "Number of seconds between stats printk()s");
48 torture_param(int, stutter
, 5, "Number of jiffies to run/halt test, 0=disable");
49 torture_param(int, verbose
, 1,
50 "Enable verbose debugging printk()s");
52 static char *torture_type
= "spin_lock";
53 module_param(torture_type
, charp
, 0444);
54 MODULE_PARM_DESC(torture_type
,
55 "Type of lock to torture (spin_lock, spin_lock_irq, mutex_lock, ...)");
57 static struct task_struct
*stats_task
;
58 static struct task_struct
**writer_tasks
;
59 static struct task_struct
**reader_tasks
;
61 static bool lock_is_write_held
;
62 static bool lock_is_read_held
;
63 static unsigned long last_lock_release
;
65 struct lock_stress_stats
{
70 /* Forward reference. */
71 static void lock_torture_cleanup(void);
74 * Operations vector for selecting different types of tests.
76 struct lock_torture_ops
{
79 int (*writelock
)(void);
80 void (*write_delay
)(struct torture_random_state
*trsp
);
81 void (*task_boost
)(struct torture_random_state
*trsp
);
82 void (*writeunlock
)(void);
83 int (*readlock
)(void);
84 void (*read_delay
)(struct torture_random_state
*trsp
);
85 void (*readunlock
)(void);
87 unsigned long flags
; /* for irq spinlocks */
91 struct lock_torture_cxt
{
92 int nrealwriters_stress
;
93 int nrealreaders_stress
;
96 atomic_t n_lock_torture_errors
;
97 struct lock_torture_ops
*cur_ops
;
98 struct lock_stress_stats
*lwsa
; /* writer statistics */
99 struct lock_stress_stats
*lrsa
; /* reader statistics */
101 static struct lock_torture_cxt cxt
= { 0, 0, false, false,
105 * Definitions for lock torture testing.
108 static int torture_lock_busted_write_lock(void)
110 return 0; /* BUGGY, do not use in real life!!! */
113 static void torture_lock_busted_write_delay(struct torture_random_state
*trsp
)
115 const unsigned long longdelay_ms
= 100;
117 /* We want a long delay occasionally to force massive contention. */
118 if (!(torture_random(trsp
) %
119 (cxt
.nrealwriters_stress
* 2000 * longdelay_ms
)))
120 mdelay(longdelay_ms
);
121 if (!(torture_random(trsp
) % (cxt
.nrealwriters_stress
* 20000)))
122 torture_preempt_schedule(); /* Allow test to be preempted. */
125 static void torture_lock_busted_write_unlock(void)
127 /* BUGGY, do not use in real life!!! */
130 static void torture_boost_dummy(struct torture_random_state
*trsp
)
132 /* Only rtmutexes care about priority */
135 static struct lock_torture_ops lock_busted_ops
= {
136 .writelock
= torture_lock_busted_write_lock
,
137 .write_delay
= torture_lock_busted_write_delay
,
138 .task_boost
= torture_boost_dummy
,
139 .writeunlock
= torture_lock_busted_write_unlock
,
143 .name
= "lock_busted"
146 static DEFINE_SPINLOCK(torture_spinlock
);
148 static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock
)
150 spin_lock(&torture_spinlock
);
154 static void torture_spin_lock_write_delay(struct torture_random_state
*trsp
)
156 const unsigned long shortdelay_us
= 2;
157 const unsigned long longdelay_ms
= 100;
159 /* We want a short delay mostly to emulate likely code, and
160 * we want a long delay occasionally to force massive contention.
162 if (!(torture_random(trsp
) %
163 (cxt
.nrealwriters_stress
* 2000 * longdelay_ms
)))
164 mdelay(longdelay_ms
);
165 if (!(torture_random(trsp
) %
166 (cxt
.nrealwriters_stress
* 2 * shortdelay_us
)))
167 udelay(shortdelay_us
);
168 if (!(torture_random(trsp
) % (cxt
.nrealwriters_stress
* 20000)))
169 torture_preempt_schedule(); /* Allow test to be preempted. */
172 static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock
)
174 spin_unlock(&torture_spinlock
);
177 static struct lock_torture_ops spin_lock_ops
= {
178 .writelock
= torture_spin_lock_write_lock
,
179 .write_delay
= torture_spin_lock_write_delay
,
180 .task_boost
= torture_boost_dummy
,
181 .writeunlock
= torture_spin_lock_write_unlock
,
188 static int torture_spin_lock_write_lock_irq(void)
189 __acquires(torture_spinlock
)
193 spin_lock_irqsave(&torture_spinlock
, flags
);
194 cxt
.cur_ops
->flags
= flags
;
198 static void torture_lock_spin_write_unlock_irq(void)
199 __releases(torture_spinlock
)
201 spin_unlock_irqrestore(&torture_spinlock
, cxt
.cur_ops
->flags
);
204 static struct lock_torture_ops spin_lock_irq_ops
= {
205 .writelock
= torture_spin_lock_write_lock_irq
,
206 .write_delay
= torture_spin_lock_write_delay
,
207 .task_boost
= torture_boost_dummy
,
208 .writeunlock
= torture_lock_spin_write_unlock_irq
,
212 .name
= "spin_lock_irq"
215 static DEFINE_RWLOCK(torture_rwlock
);
217 static int torture_rwlock_write_lock(void) __acquires(torture_rwlock
)
219 write_lock(&torture_rwlock
);
223 static void torture_rwlock_write_delay(struct torture_random_state
*trsp
)
225 const unsigned long shortdelay_us
= 2;
226 const unsigned long longdelay_ms
= 100;
228 /* We want a short delay mostly to emulate likely code, and
229 * we want a long delay occasionally to force massive contention.
231 if (!(torture_random(trsp
) %
232 (cxt
.nrealwriters_stress
* 2000 * longdelay_ms
)))
233 mdelay(longdelay_ms
);
235 udelay(shortdelay_us
);
238 static void torture_rwlock_write_unlock(void) __releases(torture_rwlock
)
240 write_unlock(&torture_rwlock
);
243 static int torture_rwlock_read_lock(void) __acquires(torture_rwlock
)
245 read_lock(&torture_rwlock
);
249 static void torture_rwlock_read_delay(struct torture_random_state
*trsp
)
251 const unsigned long shortdelay_us
= 10;
252 const unsigned long longdelay_ms
= 100;
254 /* We want a short delay mostly to emulate likely code, and
255 * we want a long delay occasionally to force massive contention.
257 if (!(torture_random(trsp
) %
258 (cxt
.nrealreaders_stress
* 2000 * longdelay_ms
)))
259 mdelay(longdelay_ms
);
261 udelay(shortdelay_us
);
264 static void torture_rwlock_read_unlock(void) __releases(torture_rwlock
)
266 read_unlock(&torture_rwlock
);
269 static struct lock_torture_ops rw_lock_ops
= {
270 .writelock
= torture_rwlock_write_lock
,
271 .write_delay
= torture_rwlock_write_delay
,
272 .task_boost
= torture_boost_dummy
,
273 .writeunlock
= torture_rwlock_write_unlock
,
274 .readlock
= torture_rwlock_read_lock
,
275 .read_delay
= torture_rwlock_read_delay
,
276 .readunlock
= torture_rwlock_read_unlock
,
280 static int torture_rwlock_write_lock_irq(void) __acquires(torture_rwlock
)
284 write_lock_irqsave(&torture_rwlock
, flags
);
285 cxt
.cur_ops
->flags
= flags
;
289 static void torture_rwlock_write_unlock_irq(void)
290 __releases(torture_rwlock
)
292 write_unlock_irqrestore(&torture_rwlock
, cxt
.cur_ops
->flags
);
295 static int torture_rwlock_read_lock_irq(void) __acquires(torture_rwlock
)
299 read_lock_irqsave(&torture_rwlock
, flags
);
300 cxt
.cur_ops
->flags
= flags
;
304 static void torture_rwlock_read_unlock_irq(void)
305 __releases(torture_rwlock
)
307 read_unlock_irqrestore(&torture_rwlock
, cxt
.cur_ops
->flags
);
310 static struct lock_torture_ops rw_lock_irq_ops
= {
311 .writelock
= torture_rwlock_write_lock_irq
,
312 .write_delay
= torture_rwlock_write_delay
,
313 .task_boost
= torture_boost_dummy
,
314 .writeunlock
= torture_rwlock_write_unlock_irq
,
315 .readlock
= torture_rwlock_read_lock_irq
,
316 .read_delay
= torture_rwlock_read_delay
,
317 .readunlock
= torture_rwlock_read_unlock_irq
,
318 .name
= "rw_lock_irq"
321 static DEFINE_MUTEX(torture_mutex
);
323 static int torture_mutex_lock(void) __acquires(torture_mutex
)
325 mutex_lock(&torture_mutex
);
329 static void torture_mutex_delay(struct torture_random_state
*trsp
)
331 const unsigned long longdelay_ms
= 100;
333 /* We want a long delay occasionally to force massive contention. */
334 if (!(torture_random(trsp
) %
335 (cxt
.nrealwriters_stress
* 2000 * longdelay_ms
)))
336 mdelay(longdelay_ms
* 5);
338 mdelay(longdelay_ms
/ 5);
339 if (!(torture_random(trsp
) % (cxt
.nrealwriters_stress
* 20000)))
340 torture_preempt_schedule(); /* Allow test to be preempted. */
343 static void torture_mutex_unlock(void) __releases(torture_mutex
)
345 mutex_unlock(&torture_mutex
);
348 static struct lock_torture_ops mutex_lock_ops
= {
349 .writelock
= torture_mutex_lock
,
350 .write_delay
= torture_mutex_delay
,
351 .task_boost
= torture_boost_dummy
,
352 .writeunlock
= torture_mutex_unlock
,
359 #include <linux/ww_mutex.h>
360 static DEFINE_WD_CLASS(torture_ww_class
);
361 static DEFINE_WW_MUTEX(torture_ww_mutex_0
, &torture_ww_class
);
362 static DEFINE_WW_MUTEX(torture_ww_mutex_1
, &torture_ww_class
);
363 static DEFINE_WW_MUTEX(torture_ww_mutex_2
, &torture_ww_class
);
365 static int torture_ww_mutex_lock(void)
366 __acquires(torture_ww_mutex_0
)
367 __acquires(torture_ww_mutex_1
)
368 __acquires(torture_ww_mutex_2
)
371 struct reorder_lock
{
372 struct list_head link
;
373 struct ww_mutex
*lock
;
374 } locks
[3], *ll
, *ln
;
375 struct ww_acquire_ctx ctx
;
377 locks
[0].lock
= &torture_ww_mutex_0
;
378 list_add(&locks
[0].link
, &list
);
380 locks
[1].lock
= &torture_ww_mutex_1
;
381 list_add(&locks
[1].link
, &list
);
383 locks
[2].lock
= &torture_ww_mutex_2
;
384 list_add(&locks
[2].link
, &list
);
386 ww_acquire_init(&ctx
, &torture_ww_class
);
388 list_for_each_entry(ll
, &list
, link
) {
391 err
= ww_mutex_lock(ll
->lock
, &ctx
);
396 list_for_each_entry_continue_reverse(ln
, &list
, link
)
397 ww_mutex_unlock(ln
->lock
);
402 ww_mutex_lock_slow(ll
->lock
, &ctx
);
403 list_move(&ll
->link
, &list
);
406 ww_acquire_fini(&ctx
);
410 static void torture_ww_mutex_unlock(void)
411 __releases(torture_ww_mutex_0
)
412 __releases(torture_ww_mutex_1
)
413 __releases(torture_ww_mutex_2
)
415 ww_mutex_unlock(&torture_ww_mutex_0
);
416 ww_mutex_unlock(&torture_ww_mutex_1
);
417 ww_mutex_unlock(&torture_ww_mutex_2
);
420 static struct lock_torture_ops ww_mutex_lock_ops
= {
421 .writelock
= torture_ww_mutex_lock
,
422 .write_delay
= torture_mutex_delay
,
423 .task_boost
= torture_boost_dummy
,
424 .writeunlock
= torture_ww_mutex_unlock
,
428 .name
= "ww_mutex_lock"
431 #ifdef CONFIG_RT_MUTEXES
432 static DEFINE_RT_MUTEX(torture_rtmutex
);
434 static int torture_rtmutex_lock(void) __acquires(torture_rtmutex
)
436 rt_mutex_lock(&torture_rtmutex
);
440 static void torture_rtmutex_boost(struct torture_random_state
*trsp
)
442 const unsigned int factor
= 50000; /* yes, quite arbitrary */
444 if (!rt_task(current
)) {
446 * Boost priority once every ~50k operations. When the
447 * task tries to take the lock, the rtmutex it will account
448 * for the new priority, and do any corresponding pi-dance.
450 if (trsp
&& !(torture_random(trsp
) %
451 (cxt
.nrealwriters_stress
* factor
))) {
452 sched_set_fifo(current
);
453 } else /* common case, do nothing */
457 * The task will remain boosted for another ~500k operations,
458 * then restored back to its original prio, and so forth.
460 * When @trsp is nil, we want to force-reset the task for
461 * stopping the kthread.
463 if (!trsp
|| !(torture_random(trsp
) %
464 (cxt
.nrealwriters_stress
* factor
* 2))) {
465 sched_set_normal(current
, 0);
466 } else /* common case, do nothing */
471 static void torture_rtmutex_delay(struct torture_random_state
*trsp
)
473 const unsigned long shortdelay_us
= 2;
474 const unsigned long longdelay_ms
= 100;
477 * We want a short delay mostly to emulate likely code, and
478 * we want a long delay occasionally to force massive contention.
480 if (!(torture_random(trsp
) %
481 (cxt
.nrealwriters_stress
* 2000 * longdelay_ms
)))
482 mdelay(longdelay_ms
);
483 if (!(torture_random(trsp
) %
484 (cxt
.nrealwriters_stress
* 2 * shortdelay_us
)))
485 udelay(shortdelay_us
);
486 if (!(torture_random(trsp
) % (cxt
.nrealwriters_stress
* 20000)))
487 torture_preempt_schedule(); /* Allow test to be preempted. */
490 static void torture_rtmutex_unlock(void) __releases(torture_rtmutex
)
492 rt_mutex_unlock(&torture_rtmutex
);
495 static struct lock_torture_ops rtmutex_lock_ops
= {
496 .writelock
= torture_rtmutex_lock
,
497 .write_delay
= torture_rtmutex_delay
,
498 .task_boost
= torture_rtmutex_boost
,
499 .writeunlock
= torture_rtmutex_unlock
,
503 .name
= "rtmutex_lock"
507 static DECLARE_RWSEM(torture_rwsem
);
508 static int torture_rwsem_down_write(void) __acquires(torture_rwsem
)
510 down_write(&torture_rwsem
);
514 static void torture_rwsem_write_delay(struct torture_random_state
*trsp
)
516 const unsigned long longdelay_ms
= 100;
518 /* We want a long delay occasionally to force massive contention. */
519 if (!(torture_random(trsp
) %
520 (cxt
.nrealwriters_stress
* 2000 * longdelay_ms
)))
521 mdelay(longdelay_ms
* 10);
523 mdelay(longdelay_ms
/ 10);
524 if (!(torture_random(trsp
) % (cxt
.nrealwriters_stress
* 20000)))
525 torture_preempt_schedule(); /* Allow test to be preempted. */
528 static void torture_rwsem_up_write(void) __releases(torture_rwsem
)
530 up_write(&torture_rwsem
);
533 static int torture_rwsem_down_read(void) __acquires(torture_rwsem
)
535 down_read(&torture_rwsem
);
539 static void torture_rwsem_read_delay(struct torture_random_state
*trsp
)
541 const unsigned long longdelay_ms
= 100;
543 /* We want a long delay occasionally to force massive contention. */
544 if (!(torture_random(trsp
) %
545 (cxt
.nrealreaders_stress
* 2000 * longdelay_ms
)))
546 mdelay(longdelay_ms
* 2);
548 mdelay(longdelay_ms
/ 2);
549 if (!(torture_random(trsp
) % (cxt
.nrealreaders_stress
* 20000)))
550 torture_preempt_schedule(); /* Allow test to be preempted. */
553 static void torture_rwsem_up_read(void) __releases(torture_rwsem
)
555 up_read(&torture_rwsem
);
558 static struct lock_torture_ops rwsem_lock_ops
= {
559 .writelock
= torture_rwsem_down_write
,
560 .write_delay
= torture_rwsem_write_delay
,
561 .task_boost
= torture_boost_dummy
,
562 .writeunlock
= torture_rwsem_up_write
,
563 .readlock
= torture_rwsem_down_read
,
564 .read_delay
= torture_rwsem_read_delay
,
565 .readunlock
= torture_rwsem_up_read
,
569 #include <linux/percpu-rwsem.h>
570 static struct percpu_rw_semaphore pcpu_rwsem
;
572 static void torture_percpu_rwsem_init(void)
574 BUG_ON(percpu_init_rwsem(&pcpu_rwsem
));
577 static void torture_percpu_rwsem_exit(void)
579 percpu_free_rwsem(&pcpu_rwsem
);
582 static int torture_percpu_rwsem_down_write(void) __acquires(pcpu_rwsem
)
584 percpu_down_write(&pcpu_rwsem
);
588 static void torture_percpu_rwsem_up_write(void) __releases(pcpu_rwsem
)
590 percpu_up_write(&pcpu_rwsem
);
593 static int torture_percpu_rwsem_down_read(void) __acquires(pcpu_rwsem
)
595 percpu_down_read(&pcpu_rwsem
);
599 static void torture_percpu_rwsem_up_read(void) __releases(pcpu_rwsem
)
601 percpu_up_read(&pcpu_rwsem
);
604 static struct lock_torture_ops percpu_rwsem_lock_ops
= {
605 .init
= torture_percpu_rwsem_init
,
606 .exit
= torture_percpu_rwsem_exit
,
607 .writelock
= torture_percpu_rwsem_down_write
,
608 .write_delay
= torture_rwsem_write_delay
,
609 .task_boost
= torture_boost_dummy
,
610 .writeunlock
= torture_percpu_rwsem_up_write
,
611 .readlock
= torture_percpu_rwsem_down_read
,
612 .read_delay
= torture_rwsem_read_delay
,
613 .readunlock
= torture_percpu_rwsem_up_read
,
614 .name
= "percpu_rwsem_lock"
618 * Lock torture writer kthread. Repeatedly acquires and releases
619 * the lock, checking for duplicate acquisitions.
621 static int lock_torture_writer(void *arg
)
623 struct lock_stress_stats
*lwsp
= arg
;
624 DEFINE_TORTURE_RANDOM(rand
);
626 VERBOSE_TOROUT_STRING("lock_torture_writer task started");
627 set_user_nice(current
, MAX_NICE
);
630 if ((torture_random(&rand
) & 0xfffff) == 0)
631 schedule_timeout_uninterruptible(1);
633 cxt
.cur_ops
->task_boost(&rand
);
634 cxt
.cur_ops
->writelock();
635 if (WARN_ON_ONCE(lock_is_write_held
))
637 lock_is_write_held
= true;
638 if (WARN_ON_ONCE(lock_is_read_held
))
639 lwsp
->n_lock_fail
++; /* rare, but... */
641 lwsp
->n_lock_acquired
++;
642 cxt
.cur_ops
->write_delay(&rand
);
643 lock_is_write_held
= false;
644 WRITE_ONCE(last_lock_release
, jiffies
);
645 cxt
.cur_ops
->writeunlock();
647 stutter_wait("lock_torture_writer");
648 } while (!torture_must_stop());
650 cxt
.cur_ops
->task_boost(NULL
); /* reset prio */
651 torture_kthread_stopping("lock_torture_writer");
656 * Lock torture reader kthread. Repeatedly acquires and releases
659 static int lock_torture_reader(void *arg
)
661 struct lock_stress_stats
*lrsp
= arg
;
662 DEFINE_TORTURE_RANDOM(rand
);
664 VERBOSE_TOROUT_STRING("lock_torture_reader task started");
665 set_user_nice(current
, MAX_NICE
);
668 if ((torture_random(&rand
) & 0xfffff) == 0)
669 schedule_timeout_uninterruptible(1);
671 cxt
.cur_ops
->readlock();
672 lock_is_read_held
= true;
673 if (WARN_ON_ONCE(lock_is_write_held
))
674 lrsp
->n_lock_fail
++; /* rare, but... */
676 lrsp
->n_lock_acquired
++;
677 cxt
.cur_ops
->read_delay(&rand
);
678 lock_is_read_held
= false;
679 cxt
.cur_ops
->readunlock();
681 stutter_wait("lock_torture_reader");
682 } while (!torture_must_stop());
683 torture_kthread_stopping("lock_torture_reader");
688 * Create an lock-torture-statistics message in the specified buffer.
690 static void __torture_print_stats(char *page
,
691 struct lock_stress_stats
*statp
, bool write
)
695 long max
= 0, min
= statp
? statp
[0].n_lock_acquired
: 0;
698 n_stress
= write
? cxt
.nrealwriters_stress
: cxt
.nrealreaders_stress
;
699 for (i
= 0; i
< n_stress
; i
++) {
700 if (statp
[i
].n_lock_fail
)
702 sum
+= statp
[i
].n_lock_acquired
;
703 if (max
< statp
[i
].n_lock_acquired
)
704 max
= statp
[i
].n_lock_acquired
;
705 if (min
> statp
[i
].n_lock_acquired
)
706 min
= statp
[i
].n_lock_acquired
;
708 page
+= sprintf(page
,
709 "%s: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n",
710 write
? "Writes" : "Reads ",
712 !onoff_interval
&& max
/ 2 > min
? "???" : "",
713 fail
, fail
? "!!!" : "");
715 atomic_inc(&cxt
.n_lock_torture_errors
);
719 * Print torture statistics. Caller must ensure that there is only one
720 * call to this function at a given time!!! This is normally accomplished
721 * by relying on the module system to only have one copy of the module
722 * loaded, and then by giving the lock_torture_stats kthread full control
723 * (or the init/cleanup functions when lock_torture_stats thread is not
726 static void lock_torture_stats_print(void)
728 int size
= cxt
.nrealwriters_stress
* 200 + 8192;
731 if (cxt
.cur_ops
->readlock
)
732 size
+= cxt
.nrealreaders_stress
* 200 + 8192;
734 buf
= kmalloc(size
, GFP_KERNEL
);
736 pr_err("lock_torture_stats_print: Out of memory, need: %d",
741 __torture_print_stats(buf
, cxt
.lwsa
, true);
745 if (cxt
.cur_ops
->readlock
) {
746 buf
= kmalloc(size
, GFP_KERNEL
);
748 pr_err("lock_torture_stats_print: Out of memory, need: %d",
753 __torture_print_stats(buf
, cxt
.lrsa
, false);
760 * Periodically prints torture statistics, if periodic statistics printing
761 * was specified via the stat_interval module parameter.
763 * No need to worry about fullstop here, since this one doesn't reference
764 * volatile state or register callbacks.
766 static int lock_torture_stats(void *arg
)
768 VERBOSE_TOROUT_STRING("lock_torture_stats task started");
770 schedule_timeout_interruptible(stat_interval
* HZ
);
771 lock_torture_stats_print();
772 torture_shutdown_absorb("lock_torture_stats");
773 } while (!torture_must_stop());
774 torture_kthread_stopping("lock_torture_stats");
779 lock_torture_print_module_parms(struct lock_torture_ops
*cur_ops
,
782 pr_alert("%s" TORTURE_FLAG
783 "--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n",
784 torture_type
, tag
, cxt
.debug_lock
? " [debug]": "",
785 cxt
.nrealwriters_stress
, cxt
.nrealreaders_stress
, stat_interval
,
786 verbose
, shuffle_interval
, stutter
, shutdown_secs
,
787 onoff_interval
, onoff_holdoff
);
790 static void lock_torture_cleanup(void)
794 if (torture_cleanup_begin())
798 * Indicates early cleanup, meaning that the test has not run,
799 * such as when passing bogus args when loading the module.
800 * However cxt->cur_ops.init() may have been invoked, so beside
801 * perform the underlying torture-specific cleanups, cur_ops.exit()
802 * will be invoked if needed.
804 if (!cxt
.lwsa
&& !cxt
.lrsa
)
808 for (i
= 0; i
< cxt
.nrealwriters_stress
; i
++)
809 torture_stop_kthread(lock_torture_writer
,
816 for (i
= 0; i
< cxt
.nrealreaders_stress
; i
++)
817 torture_stop_kthread(lock_torture_reader
,
823 torture_stop_kthread(lock_torture_stats
, stats_task
);
824 lock_torture_stats_print(); /* -After- the stats thread is stopped! */
826 if (atomic_read(&cxt
.n_lock_torture_errors
))
827 lock_torture_print_module_parms(cxt
.cur_ops
,
828 "End of test: FAILURE");
829 else if (torture_onoff_failures())
830 lock_torture_print_module_parms(cxt
.cur_ops
,
831 "End of test: LOCK_HOTPLUG");
833 lock_torture_print_module_parms(cxt
.cur_ops
,
834 "End of test: SUCCESS");
842 if (cxt
.init_called
) {
843 if (cxt
.cur_ops
->exit
)
845 cxt
.init_called
= false;
847 torture_cleanup_end();
850 static int __init
lock_torture_init(void)
854 static struct lock_torture_ops
*torture_ops
[] = {
856 &spin_lock_ops
, &spin_lock_irq_ops
,
857 &rw_lock_ops
, &rw_lock_irq_ops
,
860 #ifdef CONFIG_RT_MUTEXES
864 &percpu_rwsem_lock_ops
,
867 if (!torture_init_begin(torture_type
, verbose
))
870 /* Process args and tell the world that the torturer is on the job. */
871 for (i
= 0; i
< ARRAY_SIZE(torture_ops
); i
++) {
872 cxt
.cur_ops
= torture_ops
[i
];
873 if (strcmp(torture_type
, cxt
.cur_ops
->name
) == 0)
876 if (i
== ARRAY_SIZE(torture_ops
)) {
877 pr_alert("lock-torture: invalid torture type: \"%s\"\n",
879 pr_alert("lock-torture types:");
880 for (i
= 0; i
< ARRAY_SIZE(torture_ops
); i
++)
881 pr_alert(" %s", torture_ops
[i
]->name
);
887 if (nwriters_stress
== 0 &&
888 (!cxt
.cur_ops
->readlock
|| nreaders_stress
== 0)) {
889 pr_alert("lock-torture: must run at least one locking thread\n");
894 if (cxt
.cur_ops
->init
) {
896 cxt
.init_called
= true;
899 if (nwriters_stress
>= 0)
900 cxt
.nrealwriters_stress
= nwriters_stress
;
902 cxt
.nrealwriters_stress
= 2 * num_online_cpus();
904 #ifdef CONFIG_DEBUG_MUTEXES
905 if (str_has_prefix(torture_type
, "mutex"))
906 cxt
.debug_lock
= true;
908 #ifdef CONFIG_DEBUG_RT_MUTEXES
909 if (str_has_prefix(torture_type
, "rtmutex"))
910 cxt
.debug_lock
= true;
912 #ifdef CONFIG_DEBUG_SPINLOCK
913 if ((str_has_prefix(torture_type
, "spin")) ||
914 (str_has_prefix(torture_type
, "rw_lock")))
915 cxt
.debug_lock
= true;
918 /* Initialize the statistics so that each run gets its own numbers. */
919 if (nwriters_stress
) {
920 lock_is_write_held
= false;
921 cxt
.lwsa
= kmalloc_array(cxt
.nrealwriters_stress
,
924 if (cxt
.lwsa
== NULL
) {
925 VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory");
930 for (i
= 0; i
< cxt
.nrealwriters_stress
; i
++) {
931 cxt
.lwsa
[i
].n_lock_fail
= 0;
932 cxt
.lwsa
[i
].n_lock_acquired
= 0;
936 if (cxt
.cur_ops
->readlock
) {
937 if (nreaders_stress
>= 0)
938 cxt
.nrealreaders_stress
= nreaders_stress
;
941 * By default distribute evenly the number of
942 * readers and writers. We still run the same number
943 * of threads as the writer-only locks default.
945 if (nwriters_stress
< 0) /* user doesn't care */
946 cxt
.nrealwriters_stress
= num_online_cpus();
947 cxt
.nrealreaders_stress
= cxt
.nrealwriters_stress
;
950 if (nreaders_stress
) {
951 lock_is_read_held
= false;
952 cxt
.lrsa
= kmalloc_array(cxt
.nrealreaders_stress
,
955 if (cxt
.lrsa
== NULL
) {
956 VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
963 for (i
= 0; i
< cxt
.nrealreaders_stress
; i
++) {
964 cxt
.lrsa
[i
].n_lock_fail
= 0;
965 cxt
.lrsa
[i
].n_lock_acquired
= 0;
970 lock_torture_print_module_parms(cxt
.cur_ops
, "Start of test");
972 /* Prepare torture context. */
973 if (onoff_interval
> 0) {
974 firsterr
= torture_onoff_init(onoff_holdoff
* HZ
,
975 onoff_interval
* HZ
, NULL
);
979 if (shuffle_interval
> 0) {
980 firsterr
= torture_shuffle_init(shuffle_interval
);
984 if (shutdown_secs
> 0) {
985 firsterr
= torture_shutdown_init(shutdown_secs
,
986 lock_torture_cleanup
);
991 firsterr
= torture_stutter_init(stutter
, stutter
);
996 if (nwriters_stress
) {
997 writer_tasks
= kcalloc(cxt
.nrealwriters_stress
,
998 sizeof(writer_tasks
[0]),
1000 if (writer_tasks
== NULL
) {
1001 VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
1007 if (cxt
.cur_ops
->readlock
) {
1008 reader_tasks
= kcalloc(cxt
.nrealreaders_stress
,
1009 sizeof(reader_tasks
[0]),
1011 if (reader_tasks
== NULL
) {
1012 VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory");
1013 kfree(writer_tasks
);
1014 writer_tasks
= NULL
;
1021 * Create the kthreads and start torturing (oh, those poor little locks).
1023 * TODO: Note that we interleave writers with readers, giving writers a
1024 * slight advantage, by creating its kthread first. This can be modified
1025 * for very specific needs, or even let the user choose the policy, if
1028 for (i
= 0, j
= 0; i
< cxt
.nrealwriters_stress
||
1029 j
< cxt
.nrealreaders_stress
; i
++, j
++) {
1030 if (i
>= cxt
.nrealwriters_stress
)
1033 /* Create writer. */
1034 firsterr
= torture_create_kthread(lock_torture_writer
, &cxt
.lwsa
[i
],
1040 if (cxt
.cur_ops
->readlock
== NULL
|| (j
>= cxt
.nrealreaders_stress
))
1042 /* Create reader. */
1043 firsterr
= torture_create_kthread(lock_torture_reader
, &cxt
.lrsa
[j
],
1048 if (stat_interval
> 0) {
1049 firsterr
= torture_create_kthread(lock_torture_stats
, NULL
,
1059 lock_torture_cleanup();
1060 if (shutdown_secs
) {
1061 WARN_ON(!IS_MODULE(CONFIG_LOCK_TORTURE_TEST
));
1067 module_init(lock_torture_init
);
1068 module_exit(lock_torture_cleanup
);