xref: /dragonfly/sys/sys/thread.h (revision 6ab64ab6)
1 /*
2  * SYS/THREAD.H
3  *
4  *	Implements the architecture independant portion of the LWKT
5  *	subsystem.
6  *
7  * Types which must already be defined when this header is included by
8  * userland:	struct md_thread
9  */
10 
11 #ifndef _SYS_THREAD_H_
12 #define _SYS_THREAD_H_
13 
14 #ifndef _SYS_STDINT_H_
15 #include <sys/stdint.h>		/* __int types */
16 #endif
17 #ifndef _SYS_PARAM_H_
18 #include <sys/param.h>		/* MAXCOMLEN */
19 #endif
20 #ifndef _SYS_QUEUE_H_
21 #include <sys/queue.h>		/* TAILQ_* macros */
22 #endif
23 #ifndef _SYS_MSGPORT_H_
24 #include <sys/msgport.h>	/* lwkt_port */
25 #endif
26 #ifndef _SYS_TIME_H_
27 #include <sys/time.h>   	/* struct timeval */
28 #endif
29 #ifndef _SYS_LOCK_H
30 #include <sys/lock.h>
31 #endif
32 #ifndef _SYS_SPINLOCK_H_
33 #include <sys/spinlock.h>
34 #endif
35 #ifndef _SYS_IOSCHED_H_
36 #include <sys/iosched.h>
37 #endif
38 #include <machine/thread.h>
39 
40 struct globaldata;
41 struct lwp;
42 struct proc;
43 struct thread;
44 struct lwkt_queue;
45 struct lwkt_token;
46 struct lwkt_tokref;
47 struct lwkt_ipiq;
48 struct lwkt_cpu_msg;
49 struct lwkt_cpu_port;
50 struct lwkt_cpusync;
51 union sysunion;
52 
53 typedef struct lwkt_queue	*lwkt_queue_t;
54 typedef struct lwkt_token	*lwkt_token_t;
55 typedef struct lwkt_tokref	*lwkt_tokref_t;
56 typedef struct lwkt_cpu_msg	*lwkt_cpu_msg_t;
57 typedef struct lwkt_cpu_port	*lwkt_cpu_port_t;
58 typedef struct lwkt_ipiq	*lwkt_ipiq_t;
59 typedef struct lwkt_cpusync	*lwkt_cpusync_t;
60 typedef struct thread 		*thread_t;
61 
62 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue;
63 
64 /*
65  * Differentiation between kernel threads and user threads.  Userland
66  * programs which want to access to kernel structures have to define
67  * _KERNEL_STRUCTURES.  This is a kinda safety valve to prevent badly
68  * written user programs from getting an LWKT thread that is neither the
69  * kernel nor the user version.
70  */
71 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
72 #ifndef _CPU_FRAME_H_
73 #include <machine/frame.h>
74 #endif
75 #else
76 struct intrframe;
77 #endif
78 
79 /*
80  * Tokens are used to serialize access to information.  They are 'soft'
81  * serialization entities that only stay in effect while a thread is
82  * running.  If the thread blocks, other threads can run holding the same
83  * token(s).  The tokens are reacquired when the original thread resumes.
84  *
85  * A thread can depend on its serialization remaining intact through a
86  * preemption.  An interrupt which attempts to use the same token as the
87  * thread being preempted will reschedule itself for non-preemptive
88  * operation, so the new token code is capable of interlocking against
89  * interrupts as well as other cpus.  This means that your token can only
90  * be (temporarily) lost if you *explicitly* block.
91  *
92  * Tokens are managed through a helper reference structure, lwkt_tokref.  Each
93  * thread has a stack of tokref's to keep track of acquired tokens.  Multiple
94  * tokref's may reference the same token.
95  *
96  * Tokens can be held shared or exclusive.   An exclusive holder is able
97  * to set the TOK_EXCLUSIVE bit in t_count as long as no bit in the count
98  * mask is set.  If unable to accomplish this TOK_EXCLREQ can be set instead
99  * which prevents any new shared acquisitions while the exclusive requestor
100  * spins in the scheduler.  A shared holder can bump t_count by the increment
101  * value as long as neither TOK_EXCLUSIVE or TOK_EXCLREQ is set, else spin
102  * in the scheduler.
103  *
104  * Multiple exclusive tokens are handled by treating the additional tokens
105  * as a special case of the shared token, incrementing the count value.  This
106  * reduces the complexity of the token release code.
107  */
108 
109 typedef struct lwkt_token {
110     long		t_count;	/* Shared/exclreq/exclusive access */
111     struct lwkt_tokref	*t_ref;		/* Exclusive ref */
112     long		t_collisions;	/* Collision counter */
113     const char		*t_desc;	/* Descriptive name */
114 } lwkt_token;
115 
116 #define TOK_EXCLUSIVE	0x00000001	/* Exclusive lock held */
117 #define TOK_EXCLREQ	0x00000002	/* Exclusive request pending */
118 #define TOK_INCR	4		/* Shared count increment */
119 #define TOK_COUNTMASK	(~(long)(TOK_EXCLUSIVE|TOK_EXCLREQ))
120 
121 /*
122  * Static initialization for a lwkt_token.
123  */
124 #define LWKT_TOKEN_INITIALIZER(name)	\
125 {					\
126 	.t_count = 0,			\
127 	.t_ref = NULL,			\
128 	.t_collisions = 0,		\
129 	.t_desc = #name			\
130 }
131 
132 /*
133  * Assert that a particular token is held
134  */
135 #define LWKT_TOKEN_HELD_ANY(tok)	_lwkt_token_held_any(tok, curthread)
136 #define LWKT_TOKEN_HELD_EXCL(tok)	_lwkt_token_held_excl(tok, curthread)
137 
138 #define ASSERT_LWKT_TOKEN_HELD(tok)		\
139 	KKASSERT(LWKT_TOKEN_HELD_ANY(tok))
140 
141 #define ASSERT_LWKT_TOKEN_HELD_EXCL(tok)	\
142 	KKASSERT(LWKT_TOKEN_HELD_EXCL(tok))
143 
144 #define ASSERT_NO_TOKENS_HELD(td)	\
145 	KKASSERT((td)->td_toks_stop == &td->td_toks_array[0])
146 
147 /*
148  * Assert that a particular token is held and we are in a hard
149  * code execution section (interrupt, ipi, or hard code section).
150  * Hard code sections are not allowed to block or potentially block.
151  * e.g. lwkt_gettoken() would only be ok if the token were already
152  * held.
153  */
154 #define ASSERT_LWKT_TOKEN_HARD(tok)					\
155 	do {								\
156 		globaldata_t zgd __debugvar = mycpu;			\
157 		KKASSERT((tok)->t_ref &&				\
158 			 (tok)->t_ref->tr_owner == zgd->gd_curthread &&	\
159 			 zgd->gd_intr_nesting_level > 0);		\
160 	} while(0)
161 
162 /*
163  * Assert that a particular token is held and we are in a normal
164  * critical section.  Critical sections will not be preempted but
165  * can explicitly block (tsleep, lwkt_gettoken, etc).
166  */
167 #define ASSERT_LWKT_TOKEN_CRIT(tok)					\
168 	do {								\
169 		globaldata_t zgd __debugvar = mycpu;			\
170 		KKASSERT((tok)->t_ref &&				\
171 			 (tok)->t_ref->tr_owner == zgd->gd_curthread &&	\
172 			 zgd->gd_curthread->td_critcount > 0);		\
173 	} while(0)
174 
175 struct lwkt_tokref {
176     lwkt_token_t	tr_tok;		/* token in question */
177     long		tr_count;	/* TOK_EXCLUSIVE|TOK_EXCLREQ or 0 */
178     struct thread	*tr_owner;	/* me */
179 };
180 
181 #define MAXCPUFIFO      32	/* power of 2 */
182 #define MAXCPUFIFO_MASK	(MAXCPUFIFO - 1)
183 #define LWKT_MAXTOKENS	32	/* max tokens beneficially held by thread */
184 
185 /*
186  * Always cast to ipifunc_t when registering an ipi.  The actual ipi function
187  * is called with both the data and an interrupt frame, but the ipi function
188  * that is registered might only declare a data argument.
189  */
190 typedef void (*ipifunc1_t)(void *arg);
191 typedef void (*ipifunc2_t)(void *arg, int arg2);
192 typedef void (*ipifunc3_t)(void *arg, int arg2, struct intrframe *frame);
193 
194 struct lwkt_ipiq {
195     int		ip_rindex;      /* only written by target cpu */
196     int		ip_xindex;      /* written by target, indicates completion */
197     int		ip_windex;      /* only written by source cpu */
198     int		ip_drain;	/* drain source limit */
199     struct {
200 	ipifunc3_t	func;
201 	void		*arg1;
202 	int		arg2;
203 	char		filler[32 - sizeof(int) - sizeof(void *) * 2];
204     } ip_info[MAXCPUFIFO];
205 };
206 
207 /*
208  * CPU Synchronization structure.  See lwkt_cpusync_start() and
209  * lwkt_cpusync_finish() for more information.
210  */
211 typedef void (*cpusync_func_t)(void *arg);
212 
213 struct lwkt_cpusync {
214     cpumask_t	cs_mask;		/* cpus running the sync */
215     cpumask_t	cs_mack;		/* mask acknowledge */
216     cpusync_func_t cs_func;		/* function to execute */
217     void	*cs_data;		/* function data */
218 };
219 
220 /*
221  * The standard message and queue structure used for communications between
222  * cpus.  Messages are typically queued via a machine-specific non-linked
223  * FIFO matrix allowing any cpu to send a message to any other cpu without
224  * blocking.
225  */
226 typedef struct lwkt_cpu_msg {
227     void	(*cm_func)(lwkt_cpu_msg_t msg);	/* primary dispatch function */
228     int		cm_code;		/* request code if applicable */
229     int		cm_cpu;			/* reply to cpu */
230     thread_t	cm_originator;		/* originating thread for wakeup */
231 } lwkt_cpu_msg;
232 
233 /*
234  * Thread structure.  Note that ownership of a thread structure is special
235  * cased and there is no 'token'.  A thread is always owned by the cpu
236  * represented by td_gd, any manipulation of the thread by some other cpu
237  * must be done through cpu_*msg() functions.  e.g. you could request
238  * ownership of a thread that way, or hand a thread off to another cpu.
239  *
240  * NOTE: td_ucred is synchronized from the p_ucred on user->kernel syscall,
241  *	 trap, and AST/signal transitions to provide a stable ucred for
242  *	 (primarily) system calls.  This field will be NULL for pure kernel
243  *	 threads.
244  */
245 struct md_intr_info;
246 
247 struct thread {
248     TAILQ_ENTRY(thread) td_threadq;
249     TAILQ_ENTRY(thread) td_allq;
250     TAILQ_ENTRY(thread) td_sleepq;
251     lwkt_port	td_msgport;	/* built-in message port for replies */
252     struct lwp	*td_lwp;	/* (optional) associated lwp */
253     struct proc	*td_proc;	/* (optional) associated process */
254     struct pcb	*td_pcb;	/* points to pcb and top of kstack */
255     struct globaldata *td_gd;	/* associated with this cpu */
256     const char	*td_wmesg;	/* string name for blockage */
257     const volatile void	*td_wchan;	/* waiting on channel */
258     int		td_pri;		/* 0-31, 31=highest priority (note 1) */
259     int		td_critcount;	/* critical section priority */
260     u_int	td_flags;	/* TDF flags */
261     int		td_wdomain;	/* domain for wchan address (typ 0) */
262     void	(*td_preemptable)(struct thread *td, int critcount);
263     void	(*td_release)(struct thread *td);
264     char	*td_kstack;	/* kernel stack */
265     int		td_kstack_size;	/* size of kernel stack */
266     char	*td_sp;		/* kernel stack pointer for LWKT restore */
267     thread_t	(*td_switch)(struct thread *ntd);
268     __uint64_t	td_uticks;	/* Statclock hits in user mode (uS) */
269     __uint64_t	td_sticks;      /* Statclock hits in system mode (uS) */
270     __uint64_t	td_iticks;	/* Statclock hits processing intr (uS) */
271     int		td_locks;	/* lockmgr lock debugging */
272     void	*td_unused01;	/* (future I/O scheduler heuristic) */
273     int		td_refs;	/* hold position in gd_tdallq / hold free */
274     int		td_nest_count;	/* prevent splz nesting */
275     u_int	td_contended;	/* token contention count */
276     u_int	td_mpflags;	/* flags can be set by foreign cpus */
277     int		td_cscount;	/* cpu synchronization master */
278     int		td_wakefromcpu;	/* who woke me up? */
279     int		td_upri;	/* user priority (sub-priority under td_pri) */
280     int		td_type;	/* thread type, TD_TYPE_ */
281     int		td_tracker;	/* for callers to debug lock counts */
282     int		td_unused03[4];	/* for future fields */
283     struct iosched_data td_iosdata;	/* Dynamic I/O scheduling data */
284     struct timeval td_start;	/* start time for a thread/process */
285     char	td_comm[MAXCOMLEN+1]; /* typ 16+1 bytes */
286     struct thread *td_preempted; /* we preempted this thread */
287     struct ucred *td_ucred;		/* synchronized from p_ucred */
288     void	 *td_vmm;	/* vmm private data */
289     lwkt_tokref_t td_toks_have;		/* tokens we own */
290     lwkt_tokref_t td_toks_stop;		/* tokens we want */
291     struct lwkt_tokref td_toks_array[LWKT_MAXTOKENS];
292     int		td_fairq_load;		/* fairq */
293     int		td_fairq_count;		/* fairq */
294     struct globaldata *td_migrate_gd;	/* target gd for thread migration */
295 #ifdef DEBUG_CRIT_SECTIONS
296 #define CRIT_DEBUG_ARRAY_SIZE   32
297 #define CRIT_DEBUG_ARRAY_MASK   (CRIT_DEBUG_ARRAY_SIZE - 1)
298     const char	*td_crit_debug_array[CRIT_DEBUG_ARRAY_SIZE];
299     int		td_crit_debug_index;
300     int		td_in_crit_report;
301 #endif
302     struct md_thread td_mach;
303 #ifdef DEBUG_LOCKS
304 #define SPINLOCK_DEBUG_ARRAY_SIZE	32
305    int 	td_spinlock_stack_id[SPINLOCK_DEBUG_ARRAY_SIZE];
306    struct spinlock *td_spinlock_stack[SPINLOCK_DEBUG_ARRAY_SIZE];
307    void 	*td_spinlock_caller_pc[SPINLOCK_DEBUG_ARRAY_SIZE];
308 
309     /*
310      * Track lockmgr locks held; lk->lk_filename:lk->lk_lineno is the holder
311      */
312 #define LOCKMGR_DEBUG_ARRAY_SIZE	8
313     int		td_lockmgr_stack_id[LOCKMGR_DEBUG_ARRAY_SIZE];
314     struct lock	*td_lockmgr_stack[LOCKMGR_DEBUG_ARRAY_SIZE];
315 #endif
316 };
317 
318 #define td_toks_base		td_toks_array[0]
319 #define td_toks_end		td_toks_array[LWKT_MAXTOKENS]
320 
321 #define TD_TOKS_HELD(td)	((td)->td_toks_stop != &(td)->td_toks_base)
322 #define TD_TOKS_NOT_HELD(td)	((td)->td_toks_stop == &(td)->td_toks_base)
323 
324 /*
325  * Thread flags.  Note that TDF_RUNNING is cleared on the old thread after
326  * we switch to the new one, which is necessary because LWKTs don't need
327  * to hold the BGL.  This flag is used by the exit code and the managed
328  * thread migration code.  Note in addition that preemption will cause
329  * TDF_RUNNING to be cleared temporarily, so any code checking TDF_RUNNING
330  * must also check TDF_PREEMPT_LOCK.
331  *
332  * LWKT threads stay on their (per-cpu) run queue while running, not to
333  * be confused with user processes which are removed from the user scheduling
334  * run queue while actually running.
335  *
336  * td_threadq can represent the thread on one of three queues... the LWKT
337  * run queue, a tsleep queue, or an lwkt blocking queue.  The LWKT subsystem
338  * does not allow a thread to be scheduled if it already resides on some
339  * queue.
340  */
341 #define TDF_RUNNING		0x00000001	/* thread still active */
342 #define TDF_RUNQ		0x00000002	/* on an LWKT run queue */
343 #define TDF_PREEMPT_LOCK	0x00000004	/* I have been preempted */
344 #define TDF_PREEMPT_DONE	0x00000008	/* ac preemption complete */
345 #define TDF_NOSTART		0x00000010	/* do not schedule on create */
346 #define TDF_MIGRATING		0x00000020	/* thread is being migrated */
347 #define TDF_SINTR		0x00000040	/* interruptability for 'ps' */
348 #define TDF_TSLEEPQ		0x00000080	/* on a tsleep wait queue */
349 
350 #define TDF_SYSTHREAD		0x00000100	/* reserve memory may be used */
351 #define TDF_ALLOCATED_THREAD	0x00000200	/* objcache allocated thread */
352 #define TDF_ALLOCATED_STACK	0x00000400	/* objcache allocated stack */
353 #define TDF_VERBOSE		0x00000800	/* verbose on exit */
354 #define TDF_DEADLKTREAT		0x00001000	/* special lockmgr treatment */
355 #define TDF_MARKER		0x00002000	/* tdallq list scan marker */
356 #define TDF_TIMEOUT_RUNNING	0x00004000	/* tsleep timeout race */
357 #define TDF_TIMEOUT		0x00008000	/* tsleep timeout */
358 #define TDF_INTTHREAD		0x00010000	/* interrupt thread */
359 #define TDF_TSLEEP_DESCHEDULED	0x00020000	/* tsleep core deschedule */
360 #define TDF_BLOCKED		0x00040000	/* Thread is blocked */
361 #define TDF_PANICWARN		0x00080000	/* panic warning in switch */
362 #define TDF_BLOCKQ		0x00100000	/* on block queue */
363 #define TDF_FORCE_SPINPORT	0x00200000
364 #define TDF_EXITING		0x00400000	/* thread exiting */
365 #define TDF_USINGFP		0x00800000	/* thread using fp coproc */
366 #define TDF_KERNELFP		0x01000000	/* kernel using fp coproc */
367 #define TDF_DELAYED_WAKEUP	0x02000000
368 #define TDF_FIXEDCPU		0x04000000	/* running cpu is fixed */
369 #define TDF_USERMODE		0x08000000	/* in or entering user mode */
370 #define TDF_NOFAULT		0x10000000	/* force onfault on fault */
371 
372 #define TDF_MP_STOPREQ		0x00000001	/* suspend_kproc */
373 #define TDF_MP_WAKEREQ		0x00000002	/* resume_kproc */
374 #define TDF_MP_EXITWAIT		0x00000004	/* reaper, see lwp_wait() */
375 #define TDF_MP_EXITSIG		0x00000008	/* reaper, see lwp_wait() */
376 #define TDF_MP_BATCH_DEMARC	0x00000010	/* batch mode handling */
377 #define TDF_MP_DIDYIELD		0x00000020	/* effects scheduling */
378 
379 #define TD_TYPE_GENERIC		0		/* generic thread */
380 #define TD_TYPE_CRYPTO		1		/* crypto thread */
381 #define TD_TYPE_NETISR		2		/* netisr thread */
382 
383 /*
384  * Thread priorities.  Typically only one thread from any given
385  * user process scheduling queue is on the LWKT run queue at a time.
386  * Remember that there is one LWKT run queue per cpu.
387  *
388  * Critical sections are handled by bumping td_pri above TDPRI_MAX, which
389  * causes interrupts to be masked as they occur.  When this occurs a
390  * rollup flag will be set in mycpu->gd_reqflags.
391  */
392 #define TDPRI_IDLE_THREAD	0	/* the idle thread */
393 #define TDPRI_IDLE_WORK		1	/* idle work (page zero, etc) */
394 #define TDPRI_USER_SCHEDULER	2	/* user scheduler helper */
395 #define TDPRI_USER_IDLE		4	/* user scheduler idle */
396 #define TDPRI_USER_NORM		6	/* user scheduler normal */
397 #define TDPRI_USER_REAL		8	/* user scheduler real time */
398 #define TDPRI_KERN_LPSCHED	9	/* (comparison point only) */
399 #define TDPRI_KERN_USER		10	/* kernel / block in syscall */
400 #define TDPRI_KERN_DAEMON	12	/* kernel daemon (pageout, etc) */
401 #define TDPRI_SOFT_NORM		14	/* kernel / normal */
402 #define TDPRI_SOFT_TIMER	16	/* kernel / timer */
403 #define TDPRI_UNUSED19		19
404 #define TDPRI_INT_SUPPORT	20	/* kernel / high priority support */
405 #define TDPRI_INT_LOW		27	/* low priority interrupt */
406 #define TDPRI_INT_MED		28	/* medium priority interrupt */
407 #define TDPRI_INT_HIGH		29	/* high priority interrupt */
408 #define TDPRI_MAX		31
409 
410 #define LWKT_THREAD_STACK	(UPAGES * PAGE_SIZE)
411 
412 #define IN_CRITICAL_SECT(td)	((td)->td_critcount)
413 
414 #ifdef _KERNEL
415 
416 /*
417  * Global tokens
418  */
419 extern struct lwkt_token mp_token;
420 extern struct lwkt_token pmap_token;
421 extern struct lwkt_token dev_token;
422 extern struct lwkt_token vm_token;
423 extern struct lwkt_token vmspace_token;
424 extern struct lwkt_token kvm_token;
425 extern struct lwkt_token sigio_token;
426 extern struct lwkt_token tty_token;
427 extern struct lwkt_token vnode_token;
428 extern struct lwkt_token revoke_token;
429 
430 /*
431  * Procedures
432  */
433 extern struct thread *lwkt_alloc_thread(struct thread *, int, int, int);
434 extern void lwkt_init_thread(struct thread *, void *, int, int,
435 			     struct globaldata *);
436 extern void lwkt_set_interrupt_support_thread(void);
437 extern void lwkt_set_comm(thread_t, const char *, ...) __printflike(2, 3);
438 extern void lwkt_free_thread(struct thread *);
439 extern void lwkt_gdinit(struct globaldata *);
440 extern void lwkt_switch(void);
441 extern void lwkt_switch_return(struct thread *);
442 extern void lwkt_preempt(thread_t, int);
443 extern void lwkt_schedule(thread_t);
444 extern void lwkt_schedule_noresched(thread_t);
445 extern void lwkt_schedule_self(thread_t);
446 extern void lwkt_deschedule(thread_t);
447 extern void lwkt_deschedule_self(thread_t);
448 extern void lwkt_yield(void);
449 extern void lwkt_yield_quick(void);
450 extern void lwkt_user_yield(void);
451 extern void lwkt_hold(thread_t);
452 extern void lwkt_rele(thread_t);
453 extern void lwkt_passive_release(thread_t);
454 extern void lwkt_maybe_splz(thread_t);
455 
456 extern void lwkt_gettoken(lwkt_token_t);
457 extern void lwkt_gettoken_shared(lwkt_token_t);
458 extern void lwkt_gettoken_hard(lwkt_token_t);
459 extern int  lwkt_trytoken(lwkt_token_t);
460 extern void lwkt_reltoken(lwkt_token_t);
461 extern void lwkt_reltoken_hard(lwkt_token_t);
462 extern int  lwkt_cnttoken(lwkt_token_t, thread_t);
463 extern int  lwkt_getalltokens(thread_t, int);
464 extern void lwkt_relalltokens(thread_t);
465 extern void lwkt_token_init(lwkt_token_t, const char *);
466 extern void lwkt_token_uninit(lwkt_token_t);
467 
468 extern void lwkt_token_pool_init(void);
469 extern lwkt_token_t lwkt_token_pool_lookup(void *);
470 extern lwkt_token_t lwkt_getpooltoken(void *);
471 extern void lwkt_relpooltoken(void *);
472 
473 extern void lwkt_token_swap(void);
474 
475 extern void lwkt_setpri(thread_t, int);
476 extern void lwkt_setpri_initial(thread_t, int);
477 extern void lwkt_setpri_self(int);
478 extern void lwkt_schedulerclock(thread_t td);
479 extern void lwkt_setcpu_self(struct globaldata *);
480 extern void lwkt_migratecpu(int);
481 
482 extern void lwkt_giveaway(struct thread *);
483 extern void lwkt_acquire(struct thread *);
484 extern int  lwkt_send_ipiq3(struct globaldata *, ipifunc3_t, void *, int);
485 extern int  lwkt_send_ipiq3_passive(struct globaldata *, ipifunc3_t,
486 				    void *, int);
487 extern int  lwkt_send_ipiq3_bycpu(int, ipifunc3_t, void *, int);
488 extern int  lwkt_send_ipiq3_mask(cpumask_t, ipifunc3_t, void *, int);
489 extern void lwkt_wait_ipiq(struct globaldata *, int);
490 extern void lwkt_process_ipiq(void);
491 extern void lwkt_process_ipiq_frame(struct intrframe *);
492 extern void lwkt_smp_stopped(void);
493 extern void lwkt_synchronize_ipiqs(const char *);
494 
495 /* lwkt_cpusync_init() - inline function in sys/thread2.h */
496 extern void lwkt_cpusync_simple(cpumask_t, cpusync_func_t, void *);
497 extern void lwkt_cpusync_interlock(lwkt_cpusync_t);
498 extern void lwkt_cpusync_deinterlock(lwkt_cpusync_t);
499 extern void lwkt_cpusync_quick(lwkt_cpusync_t);
500 
501 extern void crit_panic(void) __dead2;
502 extern struct lwp *lwkt_preempted_proc(void);
503 
504 extern int  lwkt_create (void (*func)(void *), void *, struct thread **,
505 		struct thread *, int, int,
506 		const char *, ...) __printflike(7, 8);
507 extern void lwkt_exit (void) __dead2;
508 extern void lwkt_remove_tdallq (struct thread *);
509 
510 #endif
511 
512 #endif
513 
514