xref: /illumos-gate/usr/src/head/thread_db.h (revision d9a54dd1ef75248420c035ec1d240674f8d1f4fb)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef _THREAD_DB_H
28 #define	_THREAD_DB_H
29 
30 /*
31  *
32  *  Description:
33  *	Types, global variables, and function definitions for users
34  *	of libc_db (formerly libthread_db).
35  *
36  */
37 
38 
39 #include <sys/lwp.h>
40 #include <sys/procfs_isa.h>
41 #include <thread.h>
42 #include <proc_service.h>
43 
44 #ifdef __cplusplus
45 extern "C" {
46 #endif
47 
48 #define		TD_THR_ANY_USER_FLAGS	0xffffffff
49 #define		TD_THR_LOWEST_PRIORITY	-128
50 #define		TD_SIGNO_MASK 0
51 #define		TD_EVENTSIZE 2
52 
53 /*
54  * Opaque handle types.
55  */
56 
57 /* Client's handle for a process */
58 struct ps_prochandle;
59 
60 /* libthread's handle for a process */
61 typedef struct td_thragent td_thragent_t;
62 
63 /* The thread handle. */
64 typedef struct td_thrhandle {
65 	td_thragent_t	*th_ta_p;
66 	psaddr_t	th_unique;
67 } td_thrhandle_t;
68 
69 /* The handle for a synchronization object. */
70 typedef struct td_synchandle {
71 	td_thragent_t	*sh_ta_p;
72 	psaddr_t	sh_unique;
73 } td_synchandle_t;
74 
75 /* ------------------------------------------------------------------ */
76 
77 /*
78  * The libc_db event facility.
79  */
80 #define	BT_UISHIFT	5 /* log base 2 of BT_NBIPUI, to extract word index */
81 #define	BT_NBIPUI	(1 << BT_UISHIFT)	/* n bits per uint */
82 #define	BT_UIMASK	(BT_NBIPUI - 1)		/* to extract bit index */
83 
84 /* Bitmask of enabled events. */
85 typedef struct td_thr_events {
86 	uint_t	event_bits[TD_EVENTSIZE];
87 } td_thr_events_t;
88 
89 /* Event set manipulation macros. */
90 #define	__td_eventmask(n)	((unsigned int)1 << (((n) - 1)	\
91 				    & (BT_NBIPUI - 1)))
92 #define	__td_eventword(n)	(((unsigned int)((n) - 1))>>5)
93 
94 #define	td_event_emptyset(setp)				\
95 	{								\
96 		int _i_;						\
97 		_i_ = TD_EVENTSIZE;					\
98 		while (_i_) (setp)->event_bits[--_i_] = 0;	\
99 	}
100 
101 #define	td_event_fillset(setp)				\
102 	{								\
103 		int _i_;						\
104 		_i_ = TD_EVENTSIZE;					\
105 		while (_i_) (setp)->event_bits[--_i_] =	\
106 			0xffffffff;				\
107 	}
108 
109 #define	td_event_addset(setp, n)			\
110 	(((setp)->event_bits[__td_eventword(n)]) |= __td_eventmask(n))
111 #define	td_event_delset(setp, n)			\
112 	(((setp)->event_bits[__td_eventword(n)]) &= ~__td_eventmask(n))
113 #define	td_eventismember(setp, n)		\
114 	(__td_eventmask(n) & ((setp)->event_bits[__td_eventword(n)]))
115 #define	td_eventisempty(setp)			\
116 	(!((setp)->event_bits[0]) && !((setp)->event_bits[1]))
117 
118 typedef enum {
119 	TD_ALL_EVENTS,	/* pseudo-event number */
120 	TD_EVENT_NONE = TD_ALL_EVENTS,	/* depends on context */
121 	TD_READY,
122 	TD_SLEEP,
123 	TD_SWITCHTO,
124 	TD_SWITCHFROM,
125 	TD_LOCK_TRY,
126 	TD_CATCHSIG,
127 	TD_IDLE,
128 	TD_CREATE,
129 	TD_DEATH,
130 	TD_PREEMPT,
131 	TD_PRI_INHERIT,
132 	TD_REAP,
133 	TD_CONCURRENCY,
134 	TD_TIMEOUT,
135 	TD_MIN_EVENT_NUM = TD_READY,
136 	TD_MAX_EVENT_NUM = TD_TIMEOUT,
137 	TD_EVENTS_ENABLE = 31		/* Event reporting enabled */
138 } td_event_e;
139 
140 /*
141  *   Ways that an event type can be reported.
142  */
143 typedef enum {
144 	NOTIFY_BPT,
145 				/*
146 				 * bpt to be inserted at u.bptaddr by
147 				 * debugger
148 				 */
149 	NOTIFY_AUTOBPT,		/* bpt inserted at u.bptaddr by application */
150 	NOTIFY_SYSCALL		/* syscall u.syscallno will be invoked */
151 } td_notify_e;
152 
153 /*
154  * How an event type is reported.
155  */
156 typedef struct td_notify {
157 	td_notify_e	type;
158 	union {
159 		psaddr_t	bptaddr;
160 		int		syscallno;
161 	} u;
162 } td_notify_t;
163 
164 /*
165  * An event message.
166  */
167 typedef struct td_event_msg {
168 	td_event_e event;		/* Event type being reported */
169 	const td_thrhandle_t *th_p;	/* Thread reporting the event */
170 	union {				/* Type-dependent event data */
171 		td_synchandle_t *sh;	/* historical rubbish; ignore */
172 		uintptr_t	data;	/* valid, depending on event type */
173 	} msg;
174 } td_event_msg_t;
175 
176 /* --------------------------------------------------------------------- */
177 
178 /*
179  * Thread information structure as returned by td_thr_get_info(), and
180  * related types.
181  */
182 
183 /*
184  * Possible thread states.  TD_THR_ANY_STATE is a pseudo-state used
185  * to select threads regardless of state in td_ta_thr_iter().
186  */
187 typedef enum {
188 	TD_THR_ANY_STATE,
189 	TD_THR_UNKNOWN,
190 	TD_THR_STOPPED,
191 	TD_THR_RUN,
192 	TD_THR_ACTIVE,
193 	TD_THR_ZOMBIE,
194 	TD_THR_SLEEP,
195 	TD_THR_STOPPED_ASLEEP
196 } td_thr_state_e;
197 
198 /*
199  * Thread type: user or system.
200  * As of Solaris 9, all threads are type TD_THR_USER.
201  */
202 typedef enum {
203 	TD_THR_ANY_TYPE,	/* not used */
204 	TD_THR_USER,
205 	TD_THR_SYSTEM
206 } td_thr_type_e;
207 
208 typedef struct td_thrinfo {
209 	td_thragent_t	*ti_ta_p;	/* process handle */
210 	unsigned	ti_user_flags;	/* flags passed to thr_create() */
211 	thread_t	ti_tid;		/* tid returned by thr_create() */
212 	void		*ti_exitval;	/* thread exit value (TD_THR_ZOMBIE) */
213 	psaddr_t	ti_startfunc;	/* startfunc passed to thr_create() */
214 	psaddr_t	ti_stkbase;	/* base of thread's stack */
215 	long		ti_stksize;	/* size of thread's stack */
216 	psaddr_t	ti_ro_area;	/* address of uthread_t struct */
217 	int		ti_ro_size;	/* size of uthread_t struct */
218 	td_thr_state_e	ti_state;	/* thread state */
219 	uchar_t		ti_db_suspended; /* boolean:  suspended by debugger? */
220 	td_thr_type_e	ti_type;	/* thread type */
221 	intptr_t	ti_pc;		/* resume PC when sleeping */
222 	intptr_t	ti_sp;		/* resume SP when sleeping */
223 	short		ti_flags;	/* flags used by libthread */
224 	int		ti_pri;		/* thread priority */
225 	lwpid_t		ti_lid;		/* last LWP assigned to this thread */
226 	sigset_t	ti_sigmask;	/* signal mask */
227 	uchar_t		ti_traceme;	/* event reporting enabled? */
228 	uchar_t		ti_preemptflag;	/* was thread preemppted? */
229 	uchar_t		ti_pirecflag;	/* priority inheritance happened */
230 	sigset_t	ti_pending;	/* set of pending signals */
231 	td_thr_events_t ti_events;	/* set of enabled events */
232 } td_thrinfo_t;
233 
234 #define	ti_tls	ti_exitval	/* for source compatibility */
235 
236 typedef struct td_ta_stats {
237 	int	nthreads;	/* total number of threads in use */
238 	int	r_concurrency;	/* requested concurrency level */
239 	int	nrunnable_num;	/* numerator, avg. runnable threads */
240 	int	nrunnable_den;	/* denominator, avg. runnable threads */
241 	int	a_concurrency_num; /* numerator, achieved concurrency level */
242 	int	a_concurrency_den; /* denominator,  concurrency level */
243 	int	nlwps_num;	/* numerator, average number of LWP's in use */
244 	int	nlwps_den;	/* denom., average number of LWP's in use */
245 	int	nidle_num;	/* numerator, avg. number of idling LWP's */
246 	int	nidle_den;	/* denom., avg. number of idling LWP's */
247 } td_ta_stats_t;
248 
249 /*
250  * Iterator callback function declarations.
251  */
252 
253 /* Callback function for td_ta_tsd_iter(). */
254 typedef int	td_key_iter_f(thread_key_t, void (*destructor)(), void *);
255 
256 /* Callback function for td_ta_thr_iter(). */
257 typedef int	td_thr_iter_f(const td_thrhandle_t *, void *);
258 
259 /* Callback function for td_ta_sync_iter(). */
260 typedef int	td_sync_iter_f(const td_synchandle_t *, void *);
261 
262 /* -------------------------------------------------------------------- */
263 
264 /*
265  * Synchronization Objects
266  */
267 
268 /* Enumeration of synchronization object types. */
269 typedef enum td_sync_type_e {
270 	TD_SYNC_UNKNOWN,	/* Sync. variable of unknown type  */
271 	TD_SYNC_COND,		/* Condition variable  */
272 	TD_SYNC_MUTEX,		/* Mutex lock  */
273 	TD_SYNC_SEMA,		/* Semaphore  */
274 	TD_SYNC_RWLOCK		/* Reader/Writer lock  */
275 } td_sync_type_e;
276 
277 #define	TD_SV_MAX_FLAGS 4
278 typedef uint8_t td_sync_flags_t;
279 
280 /*
281  * Synchronization object information structure filled in by td_sync_get_info()
282  */
283 typedef struct td_syncinfo {
284 	td_thragent_t	*si_ta_p;	/* process handle */
285 	psaddr_t	si_sv_addr;	/* address of sync. object */
286 	td_sync_type_e	si_type;	/* object type */
287 	uint32_t	si_shared_type;	/* process-shared or process-private */
288 	td_sync_flags_t	si_flags[TD_SV_MAX_FLAGS];	/* flags (?) */
289 	pid_t		si_ownerpid;	/* owner's process-id (USYNC_PROCESS) */
290 	union _si_un_state {
291 		int	sem_count;	/* semaphore count */
292 		int	nreaders;	/* number of readers, -1 if writer */
293 		int	mutex_locked;	/* non-zero iff locked */
294 	} si_state;
295 	int		si_size;	/* size in bytes of synch variable */
296 	uint8_t		si_has_waiters;	/* non-zero iff at least one waiter */
297 	uint8_t		si_is_wlock;	/* non-zero iff rwlock write-locked */
298 	uint8_t		si_rcount;	/* count for locked recursive mutex */
299 	uint8_t		si_prioceiling;	/* ceiling pri (PTHREAD_PRIO_PROTECT) */
300 	td_thrhandle_t	si_owner;	/* mutex holder or write-lock holder */
301 	psaddr_t	si_data;	/* optional data */
302 } td_syncinfo_t;
303 
304 /*
305  * Statistics structures for the various synchronization objects, contained
306  * within the td_syncstats structure returned by td_sync_get_stats().
307  */
308 typedef struct {
309 	uint_t		mutex_lock;
310 	uint_t		mutex_sleep;
311 	hrtime_t	mutex_sleep_time;
312 	hrtime_t	mutex_hold_time;
313 	uint_t		mutex_try;
314 	uint_t		mutex_try_fail;
315 	uint_t		mutex_internal;		/* internal to libthread */
316 } td_mutex_stats_t;
317 
318 typedef struct {
319 	uint_t		cond_wait;
320 	uint_t		cond_timedwait;
321 	hrtime_t	cond_wait_sleep_time;
322 	hrtime_t	cond_timedwait_sleep_time;
323 	uint_t		cond_timedwait_timeout;
324 	uint_t		cond_signal;
325 	uint_t		cond_broadcast;
326 	uint_t		cond_internal;		/* internal to libthread */
327 } td_cond_stats_t;
328 
329 typedef struct {
330 	uint_t		rw_rdlock;
331 	uint_t		rw_rdlock_sleep;
332 	hrtime_t	rw_rdlock_sleep_time;
333 	uint_t		rw_rdlock_try;
334 	uint_t		rw_rdlock_try_fail;
335 	uint_t		rw_wrlock;
336 	uint_t		rw_wrlock_sleep;
337 	hrtime_t	rw_wrlock_sleep_time;
338 	hrtime_t	rw_wrlock_hold_time;
339 	uint_t		rw_wrlock_try;
340 	uint_t		rw_wrlock_try_fail;
341 } td_rwlock_stats_t;
342 
343 typedef struct {
344 	uint_t		sema_wait;
345 	uint_t		sema_wait_sleep;
346 	hrtime_t	sema_wait_sleep_time;
347 	uint_t		sema_trywait;
348 	uint_t		sema_trywait_fail;
349 	uint_t		sema_post;
350 	uint_t		sema_max_count;
351 	uint_t		sema_min_count;
352 } td_sema_stats_t;
353 
354 /*
355  * Synchronization object statistics structure filled in by td_sync_get_stats()
356  */
357 typedef struct td_syncstats {
358 	td_syncinfo_t	ss_info;	/* as returned by td_sync_get_info() */
359 	union {
360 		td_mutex_stats_t	mutex;
361 		td_cond_stats_t		cond;
362 		td_rwlock_stats_t	rwlock;
363 		td_sema_stats_t		sema;
364 		uint_t			pad[32];	/* for future growth */
365 	} ss_un;
366 } td_syncstats_t;
367 
368 /* The set of error codes. */
369 typedef enum {
370 	TD_OK,		/* generic "call succeeded" */
371 	TD_ERR,		/* generic error. */
372 	TD_NOTHR,	/* no thread can be found to satisfy query */
373 	TD_NOSV,	/* no synch. handle can be found to satisfy query */
374 	TD_NOLWP,	/* no lwp can be found to satisfy query */
375 	TD_BADPH,	/* invalid process handle */
376 	TD_BADTH,	/* invalid thread handle */
377 	TD_BADSH,	/* invalid synchronization handle */
378 	TD_BADTA,	/* invalid thread agent */
379 	TD_BADKEY,	/* invalid key */
380 	TD_NOMSG,	/* no event message for td_thr_event_getmsg() */
381 	TD_NOFPREGS,	/* FPU register set not available */
382 	TD_NOLIBTHREAD,	/* application not linked with libthread */
383 	TD_NOEVENT,	/* requested event is not supported */
384 	TD_NOCAPAB,	/* capability not available */
385 	TD_DBERR,	/* Debugger service failed */
386 	TD_NOAPLIC,	/* Operation not applicable to */
387 	TD_NOTSD,	/* No thread-specific data for this thread */
388 	TD_MALLOC,	/* Malloc failed */
389 	TD_PARTIALREG,	/* Only part of register set was writen/read */
390 	TD_NOXREGS,	/* X register set not available for given thread */
391 	TD_NOTLS,	/* There is no TLS in the specified module */
392 	TD_TLSDEFER	/* module's TLS not yet allocated by the thread */
393 }	td_err_e;
394 
395 
396 /* ----------------------------------------------------------------------- */
397 
398 /*
399  * Exported functions.
400  */
401 
402 /*
403  * Initialize the threads debug interface.
404  */
405 td_err_e
406 td_init(void);
407 
408 /*
409  * A no-op, left for historical reasons.
410  */
411 void
412 td_log(void);
413 
414 /*
415  * Allocate a new process handle ("thread agent").
416  */
417 td_err_e
418 td_ta_new(struct ps_prochandle *, td_thragent_t **);
419 
420 /*
421  * De-allocate a process handle, releasing all related resources.
422  */
423 td_err_e
424 td_ta_delete(td_thragent_t *);
425 
426 /*
427  * Map a process handle to a client process handle.
428  */
429 td_err_e
430 td_ta_get_ph(const td_thragent_t *, struct ps_prochandle **);
431 
432 /*
433  * Set the process's suggested concurrency level.
434  */
435 td_err_e
436 td_ta_setconcurrency(const td_thragent_t *, int);
437 
438 /*
439  * Get the number of threads in the process, including zombie threads.
440  */
441 td_err_e
442 td_ta_get_nthreads(const td_thragent_t *, int *);
443 
444 /*
445  * Map a tid, as returned by thr_create(), to a thread handle.
446  */
447 td_err_e
448 td_ta_map_id2thr(const td_thragent_t *, thread_t,  td_thrhandle_t *);
449 
450 /*
451  * Map the address of a synchronization object to a sync. object handle.
452  */
453 td_err_e
454 td_ta_map_addr2sync(const td_thragent_t *, psaddr_t, td_synchandle_t *);
455 
456 /*
457  * Iterate over a process's thread-specific data (TSD) keys.
458  */
459 td_err_e
460 td_ta_tsd_iter(const td_thragent_t *, td_key_iter_f *, void *);
461 
462 /*
463  * Iterate over a process's threads, including zombie threads.
464  */
465 td_err_e
466 td_ta_thr_iter(const td_thragent_t *, td_thr_iter_f *, void *,
467     td_thr_state_e, int, sigset_t *, unsigned);
468 
469 /*
470  * Iterate over a process's known synchronization objects.
471  */
472 td_err_e
473 td_ta_sync_iter(const td_thragent_t *, td_sync_iter_f *, void *);
474 
475 /*
476  * Enable/disable process statistics collection.
477  */
478 td_err_e
479 td_ta_enable_stats(const td_thragent_t *, int);
480 
481 /*
482  * Reset process statistics.
483  */
484 td_err_e
485 td_ta_reset_stats(const td_thragent_t *);
486 
487 /*
488  * Read process statistics.
489  */
490 td_err_e
491 td_ta_get_stats(const td_thragent_t *, td_ta_stats_t *);
492 
493 /*
494  * Get thread information.
495  */
496 td_err_e
497 td_thr_get_info(const td_thrhandle_t *, td_thrinfo_t *);
498 
499 /*
500  * Get the "event address" for an event type.
501  */
502 td_err_e
503 td_ta_event_addr(const td_thragent_t *, td_event_e, td_notify_t *);
504 
505 /*
506  * Enable/disable event reporting for a thread.
507  */
508 td_err_e
509 td_thr_event_enable(const td_thrhandle_t *, int);
510 
511 /*
512  * Enable a set of events for a thread.
513  */
514 td_err_e
515 td_thr_set_event(const td_thrhandle_t *, td_thr_events_t *);
516 
517 /*
518  * Disable a set of events for a thread.
519  */
520 td_err_e
521 td_thr_clear_event(const td_thrhandle_t *, td_thr_events_t *);
522 
523 /*
524  * Retrieve (and consume) an event message for a thread.
525  */
526 td_err_e
527 td_thr_event_getmsg(const td_thrhandle_t *, td_event_msg_t *);
528 
529 /*
530  * Enable a set of events in the process.
531  */
532 td_err_e
533 td_ta_set_event(const td_thragent_t *, td_thr_events_t *);
534 
535 /*
536  * Disable a set of events in the process.
537  */
538 td_err_e
539 td_ta_clear_event(const td_thragent_t *, td_thr_events_t *);
540 
541 /*
542  * Retrieve (and consume) an event message for some thread in the process.
543  */
544 td_err_e
545 td_ta_event_getmsg(const td_thragent_t *, td_event_msg_t *);
546 
547 /*
548  * Suspend a thread.
549  */
550 td_err_e
551 td_thr_dbsuspend(const td_thrhandle_t *);
552 
553 /*
554  * Resume a suspended thread.
555  */
556 td_err_e
557 td_thr_dbresume(const td_thrhandle_t *);
558 
559 /*
560  * Set a thread's signal mask.
561  */
562 td_err_e
563 td_thr_sigsetmask(const td_thrhandle_t *, const sigset_t);
564 
565 /*
566  * Set a thread's "signals-pending" set.
567  */
568 td_err_e
569 td_thr_setsigpending(const td_thrhandle_t *, uchar_t, const sigset_t);
570 
571 /*
572  * Get a thread's general register set.
573  */
574 td_err_e
575 td_thr_getgregs(const td_thrhandle_t *, prgregset_t);
576 
577 /*
578  * Set a thread's general register set.
579  */
580 td_err_e
581 td_thr_setgregs(const td_thrhandle_t *, const prgregset_t);
582 
583 /*
584  * Get a thread's floating-point register set.
585  */
586 td_err_e
587 td_thr_getfpregs(const td_thrhandle_t *, prfpregset_t *);
588 
589 /*
590  * Set a thread's floating-point register set.
591  */
592 td_err_e
593 td_thr_setfpregs(const td_thrhandle_t *, const prfpregset_t *);
594 
595 /*
596  * Get the size of the extra state register set for this architecture.
597  */
598 td_err_e
599 td_thr_getxregsize(const td_thrhandle_t *th_p, int *xregsize);
600 
601 /*
602  * Get a thread's extra state register set.
603  */
604 td_err_e
605 td_thr_getxregs(const td_thrhandle_t *th_p, void *xregs);
606 
607 /*
608  * Set a thread's extra state register set.
609  */
610 td_err_e
611 td_thr_setxregs(const td_thrhandle_t *th_p, const void *xregs);
612 
613 /*
614  * Validate a thread handle.
615  */
616 td_err_e
617 td_thr_validate(const td_thrhandle_t *);
618 
619 /*
620  * Get a thread-specific data pointer for a thread.
621  */
622 td_err_e
623 td_thr_tsd(const td_thrhandle_t *, thread_key_t, void **);
624 
625 /*
626  * Get the base address of a thread's thread local storage (TLS) block
627  * for the module (executable or shared object) identified by 'moduleid'.
628  */
629 td_err_e
630 td_thr_tlsbase(const td_thrhandle_t *, ulong_t moduleid, psaddr_t *base);
631 
632 /*
633  * Set a thread's priority.
634  */
635 td_err_e
636 td_thr_setprio(const td_thrhandle_t *, int);
637 
638 /*
639  * Iterate over the set of locks owned by a thread.
640  */
641 td_err_e
642 td_thr_lockowner(const td_thrhandle_t *, td_sync_iter_f *, void *);
643 
644 /*
645  * Return the sync. handle of the object this thread is sleeping on.
646  */
647 td_err_e
648 td_thr_sleepinfo(const td_thrhandle_t *, td_synchandle_t *);
649 
650 /*
651  * Map an lwpid, as returned by _lwp_create(), to a thread handle.
652  */
653 td_err_e
654 td_ta_map_lwp2thr(const td_thragent_t *, lwpid_t, td_thrhandle_t *th_p);
655 
656 /*
657  * Enable/disable a process's synchronization object tracking.
658  */
659 td_err_e
660 td_ta_sync_tracking_enable(const td_thragent_t *, int);
661 
662 /*
663  * Get information about a synchronization object.
664  */
665 td_err_e
666 td_sync_get_info(const td_synchandle_t *, td_syncinfo_t *);
667 
668 /*
669  * Get statistics for a synchronization object.
670  */
671 td_err_e
672 td_sync_get_stats(const td_synchandle_t *, td_syncstats_t *);
673 
674 /*
675  * Set the state of a synchronization object.
676  */
677 td_err_e
678 td_sync_setstate(const td_synchandle_t *, int value);
679 
680 /*
681  * Iterate over all threads blocked on a synchronization object.
682  */
683 td_err_e
684 td_sync_waiters(const td_synchandle_t *, td_thr_iter_f *, void *);
685 
686 #ifdef __cplusplus
687 }
688 #endif
689 
690 #endif	/* _THREAD_DB_H */
691