FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_lock.c
1 /*-
2 * Copyright (c) 2006 John Baldwin <jhb@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the author nor the names of any co-contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 /*
31 * This module holds the global variables and functions used to maintain
32 * lock_object structures.
33 */
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: releng/9.2/sys/kern/subr_lock.c 248085 2013-03-09 02:36:32Z marius $");
37
38 #include "opt_ddb.h"
39 #include "opt_mprof.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/ktr.h>
45 #include <sys/lock.h>
46 #include <sys/lock_profile.h>
47 #include <sys/malloc.h>
48 #include <sys/mutex.h>
49 #include <sys/pcpu.h>
50 #include <sys/proc.h>
51 #include <sys/sbuf.h>
52 #include <sys/sched.h>
53 #include <sys/smp.h>
54 #include <sys/sysctl.h>
55
56 #ifdef DDB
57 #include <ddb/ddb.h>
58 #endif
59
60 #include <machine/cpufunc.h>
61
62 CTASSERT(LOCK_CLASS_MAX == 15);
63
64 struct lock_class *lock_classes[LOCK_CLASS_MAX + 1] = {
65 &lock_class_mtx_spin,
66 &lock_class_mtx_sleep,
67 &lock_class_sx,
68 &lock_class_rm,
69 &lock_class_rw,
70 &lock_class_lockmgr,
71 };
72
73 void
74 lock_init(struct lock_object *lock, struct lock_class *class, const char *name,
75 const char *type, int flags)
76 {
77 int i;
78
79 /* Check for double-init and zero object. */
80 KASSERT(!lock_initalized(lock), ("lock \"%s\" %p already initialized",
81 name, lock));
82
83 /* Look up lock class to find its index. */
84 for (i = 0; i < LOCK_CLASS_MAX; i++)
85 if (lock_classes[i] == class) {
86 lock->lo_flags = i << LO_CLASSSHIFT;
87 break;
88 }
89 KASSERT(i < LOCK_CLASS_MAX, ("unknown lock class %p", class));
90
91 /* Initialize the lock object. */
92 lock->lo_name = name;
93 lock->lo_flags |= flags | LO_INITIALIZED;
94 LOCK_LOG_INIT(lock, 0);
95 WITNESS_INIT(lock, (type != NULL) ? type : name);
96 }
97
98 void
99 lock_destroy(struct lock_object *lock)
100 {
101
102 KASSERT(lock_initalized(lock), ("lock %p is not initialized", lock));
103 WITNESS_DESTROY(lock);
104 LOCK_LOG_DESTROY(lock, 0);
105 lock->lo_flags &= ~LO_INITIALIZED;
106 }
107
108 #ifdef DDB
109 DB_SHOW_COMMAND(lock, db_show_lock)
110 {
111 struct lock_object *lock;
112 struct lock_class *class;
113
114 if (!have_addr)
115 return;
116 lock = (struct lock_object *)addr;
117 if (LO_CLASSINDEX(lock) > LOCK_CLASS_MAX) {
118 db_printf("Unknown lock class: %d\n", LO_CLASSINDEX(lock));
119 return;
120 }
121 class = LOCK_CLASS(lock);
122 db_printf(" class: %s\n", class->lc_name);
123 db_printf(" name: %s\n", lock->lo_name);
124 class->lc_ddb_show(lock);
125 }
126 #endif
127
128 #ifdef LOCK_PROFILING
129
130 /*
131 * One object per-thread for each lock the thread owns. Tracks individual
132 * lock instances.
133 */
134 struct lock_profile_object {
135 LIST_ENTRY(lock_profile_object) lpo_link;
136 struct lock_object *lpo_obj;
137 const char *lpo_file;
138 int lpo_line;
139 uint16_t lpo_ref;
140 uint16_t lpo_cnt;
141 uint64_t lpo_acqtime;
142 uint64_t lpo_waittime;
143 u_int lpo_contest_locking;
144 };
145
146 /*
147 * One lock_prof for each (file, line, lock object) triple.
148 */
149 struct lock_prof {
150 SLIST_ENTRY(lock_prof) link;
151 struct lock_class *class;
152 const char *file;
153 const char *name;
154 int line;
155 int ticks;
156 uintmax_t cnt_wait_max;
157 uintmax_t cnt_max;
158 uintmax_t cnt_tot;
159 uintmax_t cnt_wait;
160 uintmax_t cnt_cur;
161 uintmax_t cnt_contest_locking;
162 };
163
164 SLIST_HEAD(lphead, lock_prof);
165
166 #define LPROF_HASH_SIZE 4096
167 #define LPROF_HASH_MASK (LPROF_HASH_SIZE - 1)
168 #define LPROF_CACHE_SIZE 4096
169
170 /*
171 * Array of objects and profs for each type of object for each cpu. Spinlocks
172 * are handled separately because a thread may be preempted and acquire a
173 * spinlock while in the lock profiling code of a non-spinlock. In this way
174 * we only need a critical section to protect the per-cpu lists.
175 */
176 struct lock_prof_type {
177 struct lphead lpt_lpalloc;
178 struct lpohead lpt_lpoalloc;
179 struct lphead lpt_hash[LPROF_HASH_SIZE];
180 struct lock_prof lpt_prof[LPROF_CACHE_SIZE];
181 struct lock_profile_object lpt_objs[LPROF_CACHE_SIZE];
182 };
183
184 struct lock_prof_cpu {
185 struct lock_prof_type lpc_types[2]; /* One for spin one for other. */
186 };
187
188 struct lock_prof_cpu *lp_cpu[MAXCPU];
189
190 volatile int lock_prof_enable = 0;
191 static volatile int lock_prof_resetting;
192
193 #define LPROF_SBUF_SIZE 256
194
195 static int lock_prof_rejected;
196 static int lock_prof_skipspin;
197 static int lock_prof_skipcount;
198
199 #ifndef USE_CPU_NANOSECONDS
200 uint64_t
201 nanoseconds(void)
202 {
203 struct bintime bt;
204 uint64_t ns;
205
206 binuptime(&bt);
207 /* From bintime2timespec */
208 ns = bt.sec * (uint64_t)1000000000;
209 ns += ((uint64_t)1000000000 * (uint32_t)(bt.frac >> 32)) >> 32;
210 return (ns);
211 }
212 #endif
213
214 static void
215 lock_prof_init_type(struct lock_prof_type *type)
216 {
217 int i;
218
219 SLIST_INIT(&type->lpt_lpalloc);
220 LIST_INIT(&type->lpt_lpoalloc);
221 for (i = 0; i < LPROF_CACHE_SIZE; i++) {
222 SLIST_INSERT_HEAD(&type->lpt_lpalloc, &type->lpt_prof[i],
223 link);
224 LIST_INSERT_HEAD(&type->lpt_lpoalloc, &type->lpt_objs[i],
225 lpo_link);
226 }
227 }
228
229 static void
230 lock_prof_init(void *arg)
231 {
232 int cpu;
233
234 for (cpu = 0; cpu <= mp_maxid; cpu++) {
235 lp_cpu[cpu] = malloc(sizeof(*lp_cpu[cpu]), M_DEVBUF,
236 M_WAITOK | M_ZERO);
237 lock_prof_init_type(&lp_cpu[cpu]->lpc_types[0]);
238 lock_prof_init_type(&lp_cpu[cpu]->lpc_types[1]);
239 }
240 }
241 SYSINIT(lockprof, SI_SUB_SMP, SI_ORDER_ANY, lock_prof_init, NULL);
242
243 /*
244 * To be certain that lock profiling has idled on all cpus before we
245 * reset, we schedule the resetting thread on all active cpus. Since
246 * all operations happen within critical sections we can be sure that
247 * it is safe to zero the profiling structures.
248 */
249 static void
250 lock_prof_idle(void)
251 {
252 struct thread *td;
253 int cpu;
254
255 td = curthread;
256 thread_lock(td);
257 CPU_FOREACH(cpu) {
258 sched_bind(td, cpu);
259 }
260 sched_unbind(td);
261 thread_unlock(td);
262 }
263
264 static void
265 lock_prof_reset_wait(void)
266 {
267
268 /*
269 * Spin relinquishing our cpu so that lock_prof_idle may
270 * run on it.
271 */
272 while (lock_prof_resetting)
273 sched_relinquish(curthread);
274 }
275
276 static void
277 lock_prof_reset(void)
278 {
279 struct lock_prof_cpu *lpc;
280 int enabled, i, cpu;
281
282 /*
283 * We not only race with acquiring and releasing locks but also
284 * thread exit. To be certain that threads exit without valid head
285 * pointers they must see resetting set before enabled is cleared.
286 * Otherwise a lock may not be removed from a per-thread list due
287 * to disabled being set but not wait for reset() to remove it below.
288 */
289 atomic_store_rel_int(&lock_prof_resetting, 1);
290 enabled = lock_prof_enable;
291 lock_prof_enable = 0;
292 lock_prof_idle();
293 /*
294 * Some objects may have migrated between CPUs. Clear all links
295 * before we zero the structures. Some items may still be linked
296 * into per-thread lists as well.
297 */
298 for (cpu = 0; cpu <= mp_maxid; cpu++) {
299 lpc = lp_cpu[cpu];
300 for (i = 0; i < LPROF_CACHE_SIZE; i++) {
301 LIST_REMOVE(&lpc->lpc_types[0].lpt_objs[i], lpo_link);
302 LIST_REMOVE(&lpc->lpc_types[1].lpt_objs[i], lpo_link);
303 }
304 }
305 for (cpu = 0; cpu <= mp_maxid; cpu++) {
306 lpc = lp_cpu[cpu];
307 bzero(lpc, sizeof(*lpc));
308 lock_prof_init_type(&lpc->lpc_types[0]);
309 lock_prof_init_type(&lpc->lpc_types[1]);
310 }
311 atomic_store_rel_int(&lock_prof_resetting, 0);
312 lock_prof_enable = enabled;
313 }
314
315 static void
316 lock_prof_output(struct lock_prof *lp, struct sbuf *sb)
317 {
318 const char *p;
319
320 for (p = lp->file; p != NULL && strncmp(p, "../", 3) == 0; p += 3);
321 sbuf_printf(sb,
322 "%8ju %9ju %11ju %11ju %11ju %6ju %6ju %2ju %6ju %s:%d (%s:%s)\n",
323 lp->cnt_max / 1000, lp->cnt_wait_max / 1000, lp->cnt_tot / 1000,
324 lp->cnt_wait / 1000, lp->cnt_cur,
325 lp->cnt_cur == 0 ? (uintmax_t)0 :
326 lp->cnt_tot / (lp->cnt_cur * 1000),
327 lp->cnt_cur == 0 ? (uintmax_t)0 :
328 lp->cnt_wait / (lp->cnt_cur * 1000),
329 (uintmax_t)0, lp->cnt_contest_locking,
330 p, lp->line, lp->class->lc_name, lp->name);
331 }
332
333 static void
334 lock_prof_sum(struct lock_prof *match, struct lock_prof *dst, int hash,
335 int spin, int t)
336 {
337 struct lock_prof_type *type;
338 struct lock_prof *l;
339 int cpu;
340
341 dst->file = match->file;
342 dst->line = match->line;
343 dst->class = match->class;
344 dst->name = match->name;
345
346 for (cpu = 0; cpu <= mp_maxid; cpu++) {
347 if (lp_cpu[cpu] == NULL)
348 continue;
349 type = &lp_cpu[cpu]->lpc_types[spin];
350 SLIST_FOREACH(l, &type->lpt_hash[hash], link) {
351 if (l->ticks == t)
352 continue;
353 if (l->file != match->file || l->line != match->line ||
354 l->name != match->name)
355 continue;
356 l->ticks = t;
357 if (l->cnt_max > dst->cnt_max)
358 dst->cnt_max = l->cnt_max;
359 if (l->cnt_wait_max > dst->cnt_wait_max)
360 dst->cnt_wait_max = l->cnt_wait_max;
361 dst->cnt_tot += l->cnt_tot;
362 dst->cnt_wait += l->cnt_wait;
363 dst->cnt_cur += l->cnt_cur;
364 dst->cnt_contest_locking += l->cnt_contest_locking;
365 }
366 }
367
368 }
369
370 static void
371 lock_prof_type_stats(struct lock_prof_type *type, struct sbuf *sb, int spin,
372 int t)
373 {
374 struct lock_prof *l;
375 int i;
376
377 for (i = 0; i < LPROF_HASH_SIZE; ++i) {
378 SLIST_FOREACH(l, &type->lpt_hash[i], link) {
379 struct lock_prof lp = {};
380
381 if (l->ticks == t)
382 continue;
383 lock_prof_sum(l, &lp, i, spin, t);
384 lock_prof_output(&lp, sb);
385 }
386 }
387 }
388
389 static int
390 dump_lock_prof_stats(SYSCTL_HANDLER_ARGS)
391 {
392 struct sbuf *sb;
393 int error, cpu, t;
394 int enabled;
395
396 error = sysctl_wire_old_buffer(req, 0);
397 if (error != 0)
398 return (error);
399 sb = sbuf_new_for_sysctl(NULL, NULL, LPROF_SBUF_SIZE, req);
400 sbuf_printf(sb, "\n%8s %9s %11s %11s %11s %6s %6s %2s %6s %s\n",
401 "max", "wait_max", "total", "wait_total", "count", "avg", "wait_avg", "cnt_hold", "cnt_lock", "name");
402 enabled = lock_prof_enable;
403 lock_prof_enable = 0;
404 lock_prof_idle();
405 t = ticks;
406 for (cpu = 0; cpu <= mp_maxid; cpu++) {
407 if (lp_cpu[cpu] == NULL)
408 continue;
409 lock_prof_type_stats(&lp_cpu[cpu]->lpc_types[0], sb, 0, t);
410 lock_prof_type_stats(&lp_cpu[cpu]->lpc_types[1], sb, 1, t);
411 }
412 lock_prof_enable = enabled;
413
414 error = sbuf_finish(sb);
415 /* Output a trailing NUL. */
416 if (error == 0)
417 error = SYSCTL_OUT(req, "", 1);
418 sbuf_delete(sb);
419 return (error);
420 }
421
422 static int
423 enable_lock_prof(SYSCTL_HANDLER_ARGS)
424 {
425 int error, v;
426
427 v = lock_prof_enable;
428 error = sysctl_handle_int(oidp, &v, v, req);
429 if (error)
430 return (error);
431 if (req->newptr == NULL)
432 return (error);
433 if (v == lock_prof_enable)
434 return (0);
435 if (v == 1)
436 lock_prof_reset();
437 lock_prof_enable = !!v;
438
439 return (0);
440 }
441
442 static int
443 reset_lock_prof_stats(SYSCTL_HANDLER_ARGS)
444 {
445 int error, v;
446
447 v = 0;
448 error = sysctl_handle_int(oidp, &v, 0, req);
449 if (error)
450 return (error);
451 if (req->newptr == NULL)
452 return (error);
453 if (v == 0)
454 return (0);
455 lock_prof_reset();
456
457 return (0);
458 }
459
460 static struct lock_prof *
461 lock_profile_lookup(struct lock_object *lo, int spin, const char *file,
462 int line)
463 {
464 const char *unknown = "(unknown)";
465 struct lock_prof_type *type;
466 struct lock_prof *lp;
467 struct lphead *head;
468 const char *p;
469 u_int hash;
470
471 p = file;
472 if (p == NULL || *p == '\0')
473 p = unknown;
474 hash = (uintptr_t)lo->lo_name * 31 + (uintptr_t)p * 31 + line;
475 hash &= LPROF_HASH_MASK;
476 type = &lp_cpu[PCPU_GET(cpuid)]->lpc_types[spin];
477 head = &type->lpt_hash[hash];
478 SLIST_FOREACH(lp, head, link) {
479 if (lp->line == line && lp->file == p &&
480 lp->name == lo->lo_name)
481 return (lp);
482
483 }
484 lp = SLIST_FIRST(&type->lpt_lpalloc);
485 if (lp == NULL) {
486 lock_prof_rejected++;
487 return (lp);
488 }
489 SLIST_REMOVE_HEAD(&type->lpt_lpalloc, link);
490 lp->file = p;
491 lp->line = line;
492 lp->class = LOCK_CLASS(lo);
493 lp->name = lo->lo_name;
494 SLIST_INSERT_HEAD(&type->lpt_hash[hash], lp, link);
495 return (lp);
496 }
497
498 static struct lock_profile_object *
499 lock_profile_object_lookup(struct lock_object *lo, int spin, const char *file,
500 int line)
501 {
502 struct lock_profile_object *l;
503 struct lock_prof_type *type;
504 struct lpohead *head;
505
506 head = &curthread->td_lprof[spin];
507 LIST_FOREACH(l, head, lpo_link)
508 if (l->lpo_obj == lo && l->lpo_file == file &&
509 l->lpo_line == line)
510 return (l);
511 type = &lp_cpu[PCPU_GET(cpuid)]->lpc_types[spin];
512 l = LIST_FIRST(&type->lpt_lpoalloc);
513 if (l == NULL) {
514 lock_prof_rejected++;
515 return (NULL);
516 }
517 LIST_REMOVE(l, lpo_link);
518 l->lpo_obj = lo;
519 l->lpo_file = file;
520 l->lpo_line = line;
521 l->lpo_cnt = 0;
522 LIST_INSERT_HEAD(head, l, lpo_link);
523
524 return (l);
525 }
526
527 void
528 lock_profile_obtain_lock_success(struct lock_object *lo, int contested,
529 uint64_t waittime, const char *file, int line)
530 {
531 static int lock_prof_count;
532 struct lock_profile_object *l;
533 int spin;
534
535 if (SCHEDULER_STOPPED())
536 return;
537
538 /* don't reset the timer when/if recursing */
539 if (!lock_prof_enable || (lo->lo_flags & LO_NOPROFILE))
540 return;
541 if (lock_prof_skipcount &&
542 (++lock_prof_count % lock_prof_skipcount) != 0)
543 return;
544 spin = (LOCK_CLASS(lo)->lc_flags & LC_SPINLOCK) ? 1 : 0;
545 if (spin && lock_prof_skipspin == 1)
546 return;
547 critical_enter();
548 /* Recheck enabled now that we're in a critical section. */
549 if (lock_prof_enable == 0)
550 goto out;
551 l = lock_profile_object_lookup(lo, spin, file, line);
552 if (l == NULL)
553 goto out;
554 l->lpo_cnt++;
555 if (++l->lpo_ref > 1)
556 goto out;
557 l->lpo_contest_locking = contested;
558 l->lpo_acqtime = nanoseconds();
559 if (waittime && (l->lpo_acqtime > waittime))
560 l->lpo_waittime = l->lpo_acqtime - waittime;
561 else
562 l->lpo_waittime = 0;
563 out:
564 critical_exit();
565 }
566
567 void
568 lock_profile_thread_exit(struct thread *td)
569 {
570 #ifdef INVARIANTS
571 struct lock_profile_object *l;
572
573 MPASS(curthread->td_critnest == 0);
574 #endif
575 /*
576 * If lock profiling was disabled we have to wait for reset to
577 * clear our pointers before we can exit safely.
578 */
579 lock_prof_reset_wait();
580 #ifdef INVARIANTS
581 LIST_FOREACH(l, &td->td_lprof[0], lpo_link)
582 printf("thread still holds lock acquired at %s:%d\n",
583 l->lpo_file, l->lpo_line);
584 LIST_FOREACH(l, &td->td_lprof[1], lpo_link)
585 printf("thread still holds lock acquired at %s:%d\n",
586 l->lpo_file, l->lpo_line);
587 #endif
588 MPASS(LIST_FIRST(&td->td_lprof[0]) == NULL);
589 MPASS(LIST_FIRST(&td->td_lprof[1]) == NULL);
590 }
591
592 void
593 lock_profile_release_lock(struct lock_object *lo)
594 {
595 struct lock_profile_object *l;
596 struct lock_prof_type *type;
597 struct lock_prof *lp;
598 uint64_t curtime, holdtime;
599 struct lpohead *head;
600 int spin;
601
602 if (SCHEDULER_STOPPED())
603 return;
604 if (lo->lo_flags & LO_NOPROFILE)
605 return;
606 spin = (LOCK_CLASS(lo)->lc_flags & LC_SPINLOCK) ? 1 : 0;
607 head = &curthread->td_lprof[spin];
608 if (LIST_FIRST(head) == NULL)
609 return;
610 critical_enter();
611 /* Recheck enabled now that we're in a critical section. */
612 if (lock_prof_enable == 0 && lock_prof_resetting == 1)
613 goto out;
614 /*
615 * If lock profiling is not enabled we still want to remove the
616 * lpo from our queue.
617 */
618 LIST_FOREACH(l, head, lpo_link)
619 if (l->lpo_obj == lo)
620 break;
621 if (l == NULL)
622 goto out;
623 if (--l->lpo_ref > 0)
624 goto out;
625 lp = lock_profile_lookup(lo, spin, l->lpo_file, l->lpo_line);
626 if (lp == NULL)
627 goto release;
628 curtime = nanoseconds();
629 if (curtime < l->lpo_acqtime)
630 goto release;
631 holdtime = curtime - l->lpo_acqtime;
632
633 /*
634 * Record if the lock has been held longer now than ever
635 * before.
636 */
637 if (holdtime > lp->cnt_max)
638 lp->cnt_max = holdtime;
639 if (l->lpo_waittime > lp->cnt_wait_max)
640 lp->cnt_wait_max = l->lpo_waittime;
641 lp->cnt_tot += holdtime;
642 lp->cnt_wait += l->lpo_waittime;
643 lp->cnt_contest_locking += l->lpo_contest_locking;
644 lp->cnt_cur += l->lpo_cnt;
645 release:
646 LIST_REMOVE(l, lpo_link);
647 type = &lp_cpu[PCPU_GET(cpuid)]->lpc_types[spin];
648 LIST_INSERT_HEAD(&type->lpt_lpoalloc, l, lpo_link);
649 out:
650 critical_exit();
651 }
652
653 static SYSCTL_NODE(_debug, OID_AUTO, lock, CTLFLAG_RD, NULL, "lock debugging");
654 static SYSCTL_NODE(_debug_lock, OID_AUTO, prof, CTLFLAG_RD, NULL,
655 "lock profiling");
656 SYSCTL_INT(_debug_lock_prof, OID_AUTO, skipspin, CTLFLAG_RW,
657 &lock_prof_skipspin, 0, "Skip profiling on spinlocks.");
658 SYSCTL_INT(_debug_lock_prof, OID_AUTO, skipcount, CTLFLAG_RW,
659 &lock_prof_skipcount, 0, "Sample approximately every N lock acquisitions.");
660 SYSCTL_INT(_debug_lock_prof, OID_AUTO, rejected, CTLFLAG_RD,
661 &lock_prof_rejected, 0, "Number of rejected profiling records");
662 SYSCTL_PROC(_debug_lock_prof, OID_AUTO, stats, CTLTYPE_STRING | CTLFLAG_RD,
663 NULL, 0, dump_lock_prof_stats, "A", "Lock profiling statistics");
664 SYSCTL_PROC(_debug_lock_prof, OID_AUTO, reset, CTLTYPE_INT | CTLFLAG_RW,
665 NULL, 0, reset_lock_prof_stats, "I", "Reset lock profiling statistics");
666 SYSCTL_PROC(_debug_lock_prof, OID_AUTO, enable, CTLTYPE_INT | CTLFLAG_RW,
667 NULL, 0, enable_lock_prof, "I", "Enable lock profiling");
668
669 #endif
Cache object: 122985a2c9be3ff02ee4146577f2cf7a
|