xref: /dragonfly/sys/sys/thread.h (revision b3f5eba6)
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 struct fdnode;
52 union sysunion;
53 
54 typedef struct lwkt_queue	*lwkt_queue_t;
55 typedef struct lwkt_token	*lwkt_token_t;
56 typedef struct lwkt_tokref	*lwkt_tokref_t;
57 typedef struct lwkt_cpu_msg	*lwkt_cpu_msg_t;
58 typedef struct lwkt_cpu_port	*lwkt_cpu_port_t;
59 typedef struct lwkt_ipiq	*lwkt_ipiq_t;
60 typedef struct lwkt_cpusync	*lwkt_cpusync_t;
61 typedef struct thread 		*thread_t;
62 
63 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue;
64 
65 /*
66  * Differentiation between kernel threads and user threads.  Userland
67  * programs which want to access to kernel structures have to define
68  * _KERNEL_STRUCTURES.  This is a kinda safety valve to prevent badly
69  * written user programs from getting an LWKT thread that is neither the
70  * kernel nor the user version.
71  */
72 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
73 #ifndef _CPU_FRAME_H_
74 #include <machine/frame.h>
75 #endif
76 #else
77 struct intrframe;
78 #endif
79 
80 /*
81  * Tokens are used to serialize access to information.  They are 'soft'
82  * serialization entities that only stay in effect while a thread is
83  * running.  If the thread blocks, other threads can run holding the same
84  * token(s).  The tokens are reacquired when the original thread resumes.
85  *
86  * Tokens guarantee that no deadlock can happen regardless of type or
87  * ordering.  However, obtaining the same token first shared, then
88  * stacking exclusive, is not allowed and will panic.
89  *
90  * A thread can depend on its serialization remaining intact through a
91  * preemption.  An interrupt which attempts to use the same token as the
92  * thread being preempted will reschedule itself for non-preemptive
93  * operation, so the new token code is capable of interlocking against
94  * interrupts as well as other cpus.  This means that your token can only
95  * be (temporarily) lost if you *explicitly* block.
96  *
97  * Tokens are managed through a helper reference structure, lwkt_tokref.  Each
98  * thread has a stack of tokref's to keep track of acquired tokens.  Multiple
99  * tokref's may reference the same token.
100  *
101  * EXCLUSIVE TOKENS
102  *	Acquiring an exclusive token requires acquiring the EXCLUSIVE bit
103  *	with count == 0.  If the exclusive bit cannot be acquired, EXCLREQ
104  *	is set.  Once acquired, EXCLREQ is cleared (but could get set by
105  *	another thread also trying for an exclusive lock at any time).
106  *
107  * SHARED TOKENS
108  *	Acquiring a shared token requires waiting for the EXCLUSIVE bit
109  *	to be cleared and then acquiring a count.  A shared lock request
110  *	can temporarily acquire a count and then back it out if it is
111  *	unable to obtain the EXCLUSIVE bit, allowing fetchadd to be used.
112  *
113  *	A thread attempting to get a single shared token will defer to
114  *	pending exclusive requesters.  However, a thread already holding
115  *	one or more tokens and trying to get an additional shared token
116  *	cannot defer to exclusive requesters because doing so can lead
117  *	to a deadlock.
118  *
119  * Multiple exclusive tokens are handled by treating the additional tokens
120  * as a special case of the shared token, incrementing the count value.  This
121  * reduces the complexity of the token release code.
122  */
123 
124 struct lwkt_token {
125     long		t_count;	/* Shared/exclreq/exclusive access */
126     struct lwkt_tokref	*t_ref;		/* Exclusive ref */
127     long		t_collisions;	/* Collision counter */
128     const char		*t_desc;	/* Descriptive name */
129 };
130 
131 #define TOK_EXCLUSIVE	0x00000001	/* Exclusive lock held */
132 #define TOK_EXCLREQ	0x00000002	/* Exclusive request pending */
133 #define TOK_INCR	4		/* Shared count increment */
134 #define TOK_COUNTMASK	(~(long)(TOK_EXCLUSIVE|TOK_EXCLREQ))
135 
136 /*
137  * Static initialization for a lwkt_token.
138  */
139 #define LWKT_TOKEN_INITIALIZER(name)	\
140 {					\
141 	.t_count = 0,			\
142 	.t_ref = NULL,			\
143 	.t_collisions = 0,		\
144 	.t_desc = #name			\
145 }
146 
147 /*
148  * Assert that a particular token is held
149  */
150 #define LWKT_TOKEN_HELD_ANY(tok)	_lwkt_token_held_any(tok, curthread)
151 #define LWKT_TOKEN_HELD_EXCL(tok)	_lwkt_token_held_excl(tok, curthread)
152 
153 #define ASSERT_LWKT_TOKEN_HELD(tok)		\
154 	KKASSERT(LWKT_TOKEN_HELD_ANY(tok))
155 
156 #define ASSERT_LWKT_TOKEN_HELD_EXCL(tok)	\
157 	KKASSERT(LWKT_TOKEN_HELD_EXCL(tok))
158 
159 #define ASSERT_NO_TOKENS_HELD(td)	\
160 	KKASSERT((td)->td_toks_stop == &td->td_toks_array[0])
161 
162 struct lwkt_tokref {
163     lwkt_token_t	tr_tok;		/* token in question */
164     long		tr_count;	/* TOK_EXCLUSIVE|TOK_EXCLREQ or 0 */
165     struct thread	*tr_owner;	/* me */
166 };
167 
168 #define MAXCPUFIFO      256	/* power of 2 */
169 #define MAXCPUFIFO_MASK	(MAXCPUFIFO - 1)
170 #define LWKT_MAXTOKENS	32	/* max tokens beneficially held by thread */
171 
172 /*
173  * Always cast to ipifunc_t when registering an ipi.  The actual ipi function
174  * is called with both the data and an interrupt frame, but the ipi function
175  * that is registered might only declare a data argument.
176  */
177 typedef void (*ipifunc1_t)(void *arg);
178 typedef void (*ipifunc2_t)(void *arg, int arg2);
179 typedef void (*ipifunc3_t)(void *arg, int arg2, struct intrframe *frame);
180 
181 struct lwkt_ipiq {
182     int		ip_rindex;      /* only written by target cpu */
183     int		ip_xindex;      /* written by target, indicates completion */
184     int		ip_windex;      /* only written by source cpu */
185     int		ip_drain;	/* drain source limit */
186     struct {
187 	ipifunc3_t	func;
188 	void		*arg1;
189 	int		arg2;
190 	char		filler[32 - sizeof(int) - sizeof(void *) * 2];
191     } ip_info[MAXCPUFIFO];
192 };
193 
194 /*
195  * CPU Synchronization structure.  See lwkt_cpusync_start() and
196  * lwkt_cpusync_finish() for more information.
197  */
198 typedef void (*cpusync_func_t)(void *arg);
199 
200 struct lwkt_cpusync {
201     cpumask_t	cs_mask;		/* cpus running the sync */
202     cpumask_t	cs_mack;		/* mask acknowledge */
203     cpusync_func_t cs_func;		/* function to execute */
204     void	*cs_data;		/* function data */
205 };
206 
207 /*
208  * The standard message and queue structure used for communications between
209  * cpus.  Messages are typically queued via a machine-specific non-linked
210  * FIFO matrix allowing any cpu to send a message to any other cpu without
211  * blocking.
212  */
213 typedef struct lwkt_cpu_msg {
214     void	(*cm_func)(lwkt_cpu_msg_t msg);	/* primary dispatch function */
215     int		cm_code;		/* request code if applicable */
216     int		cm_cpu;			/* reply to cpu */
217     thread_t	cm_originator;		/* originating thread for wakeup */
218 } lwkt_cpu_msg;
219 
220 /*
221  * per-thread file descriptor cache
222  */
223 struct fdcache {
224 	int     fd;			/* descriptor being cached */
225 	int     locked;
226 	struct file *fp;		/* cached referenced fp */
227 	int	lru;
228 	int	unused[3];
229 } __cachealign;
230 
231 #define NFDCACHE	4		/* max fd's cached by a thread */
232 
233 /* Linux task_struct, used by the drm subsystem */
234 struct task_struct {
235 	volatile long state;
236 };
237 
238 /*
239  * Thread structure.  Note that ownership of a thread structure is special
240  * cased and there is no 'token'.  A thread is always owned by the cpu
241  * represented by td_gd, any manipulation of the thread by some other cpu
242  * must be done through cpu_*msg() functions.  e.g. you could request
243  * ownership of a thread that way, or hand a thread off to another cpu.
244  *
245  * NOTE: td_ucred is synchronized from the p_ucred on user->kernel syscall,
246  *	 trap, and AST/signal transitions to provide a stable ucred for
247  *	 (primarily) system calls.  This field will be NULL for pure kernel
248  *	 threads.
249  */
250 struct md_intr_info;
251 
252 struct thread {
253     TAILQ_ENTRY(thread) td_threadq;
254     TAILQ_ENTRY(thread) td_allq;
255     TAILQ_ENTRY(thread) td_sleepq;
256     lwkt_port	td_msgport;	/* built-in message port for replies */
257     struct lwp	*td_lwp;	/* (optional) associated lwp */
258     struct proc	*td_proc;	/* (optional) associated process */
259     struct pcb	*td_pcb;	/* points to pcb and top of kstack */
260     struct globaldata *td_gd;	/* associated with this cpu */
261     const char	*td_wmesg;	/* string name for blockage */
262     const volatile void	*td_wchan;	/* waiting on channel */
263     int		td_pri;		/* 0-31, 31=highest priority (note 1) */
264     int		td_critcount;	/* critical section priority */
265     u_int	td_flags;	/* TDF flags */
266     int		td_wdomain;	/* domain for wchan address (typ 0) */
267     void	(*td_preemptable)(struct thread *td, int critcount);
268     void	(*td_release)(struct thread *td);
269     char	*td_kstack;	/* kernel stack */
270     int		td_kstack_size;	/* size of kernel stack */
271     char	*td_sp;		/* kernel stack pointer for LWKT restore */
272     thread_t	(*td_switch)(struct thread *ntd);
273     __uint64_t	td_uticks;	/* Statclock hits in user mode (uS) */
274     __uint64_t	td_sticks;      /* Statclock hits in system mode (uS) */
275     __uint64_t	td_iticks;	/* Statclock hits processing intr (uS) */
276     int		td_locks;	/* lockmgr lock debugging */
277     struct plimit *td_limit;	/* synchronized from proc->p_limit */
278     int		td_refs;	/* hold position in gd_tdallq / hold free */
279     int		td_nest_count;	/* prevent splz nesting */
280     u_int	td_contended;	/* token contention count */
281     u_int	td_mpflags;	/* flags can be set by foreign cpus */
282     int		td_cscount;	/* cpu synchronization master */
283     int		td_wakefromcpu;	/* who woke me up? */
284     int		td_upri;	/* user priority (sub-priority under td_pri) */
285     int		td_type;	/* thread type, TD_TYPE_ */
286     int		td_tracker;	/* for callers to debug lock counts */
287     int		td_fdcache_lru;
288     int		td_unused03[3];	/* for future fields */
289     struct iosched_data td_iosdata;	/* Dynamic I/O scheduling data */
290     struct timeval td_start;	/* start time for a thread/process */
291     char	td_comm[MAXCOMLEN+1]; /* typ 16+1 bytes */
292     struct thread *td_preempted; /* we preempted this thread */
293     struct ucred *td_ucred;	/* synchronized from proc->p_ucred */
294     void	 *td_vmm;	/* vmm private data */
295     lwkt_tokref_t td_toks_have;		/* tokens we own */
296     lwkt_tokref_t td_toks_stop;		/* tokens we want */
297     struct lwkt_tokref td_toks_array[LWKT_MAXTOKENS];
298     int		td_fairq_load;		/* fairq */
299     int		td_fairq_count;		/* fairq */
300     struct globaldata *td_migrate_gd;	/* target gd for thread migration */
301     struct fdcache    td_fdcache[NFDCACHE];
302     struct task_struct	td_linux_task;	/* Linux task identifier */
303 #ifdef DEBUG_CRIT_SECTIONS
304 #define CRIT_DEBUG_ARRAY_SIZE   32
305 #define CRIT_DEBUG_ARRAY_MASK   (CRIT_DEBUG_ARRAY_SIZE - 1)
306     const char	*td_crit_debug_array[CRIT_DEBUG_ARRAY_SIZE];
307     int		td_crit_debug_index;
308     int		td_in_crit_report;
309 #endif
310     struct md_thread td_mach;
311 #ifdef DEBUG_LOCKS
312 #define SPINLOCK_DEBUG_ARRAY_SIZE	32
313    int 	td_spinlock_stack_id[SPINLOCK_DEBUG_ARRAY_SIZE];
314    struct spinlock *td_spinlock_stack[SPINLOCK_DEBUG_ARRAY_SIZE];
315    void 	*td_spinlock_caller_pc[SPINLOCK_DEBUG_ARRAY_SIZE];
316 
317     /*
318      * Track lockmgr locks held; lk->lk_filename:lk->lk_lineno is the holder
319      */
320 #define LOCKMGR_DEBUG_ARRAY_SIZE	8
321     int		td_lockmgr_stack_id[LOCKMGR_DEBUG_ARRAY_SIZE];
322     struct lock	*td_lockmgr_stack[LOCKMGR_DEBUG_ARRAY_SIZE];
323 #endif
324 };
325 
326 #define td_toks_base		td_toks_array[0]
327 #define td_toks_end		td_toks_array[LWKT_MAXTOKENS]
328 
329 #define TD_TOKS_HELD(td)	((td)->td_toks_stop != &(td)->td_toks_base)
330 #define TD_TOKS_NOT_HELD(td)	((td)->td_toks_stop == &(td)->td_toks_base)
331 
332 /*
333  * Thread flags.  Note that TDF_RUNNING is cleared on the old thread after
334  * we switch to the new one, which is necessary because LWKTs don't need
335  * to hold the BGL.  This flag is used by the exit code and the managed
336  * thread migration code.  Note in addition that preemption will cause
337  * TDF_RUNNING to be cleared temporarily, so any code checking TDF_RUNNING
338  * must also check TDF_PREEMPT_LOCK.
339  *
340  * LWKT threads stay on their (per-cpu) run queue while running, not to
341  * be confused with user processes which are removed from the user scheduling
342  * run queue while actually running.
343  *
344  * td_threadq can represent the thread on one of three queues... the LWKT
345  * run queue, a tsleep queue, or an lwkt blocking queue.  The LWKT subsystem
346  * does not allow a thread to be scheduled if it already resides on some
347  * queue.
348  */
349 #define TDF_RUNNING		0x00000001	/* thread still active */
350 #define TDF_RUNQ		0x00000002	/* on an LWKT run queue */
351 #define TDF_PREEMPT_LOCK	0x00000004	/* I have been preempted */
352 #define TDF_PREEMPT_DONE	0x00000008	/* ac preemption complete */
353 #define TDF_NOSTART		0x00000010	/* do not schedule on create */
354 #define TDF_MIGRATING		0x00000020	/* thread is being migrated */
355 #define TDF_SINTR		0x00000040	/* interruptability for 'ps' */
356 #define TDF_TSLEEPQ		0x00000080	/* on a tsleep wait queue */
357 
358 #define TDF_SYSTHREAD		0x00000100	/* reserve memory may be used */
359 #define TDF_ALLOCATED_THREAD	0x00000200	/* objcache allocated thread */
360 #define TDF_ALLOCATED_STACK	0x00000400	/* objcache allocated stack */
361 #define TDF_FPU_HEUR		0x00000800	/* active restore on switch */
362 #define TDF_DEADLKTREAT		0x00001000	/* special lockmgr treatment */
363 #define TDF_MARKER		0x00002000	/* tdallq list scan marker */
364 #define TDF_TIMEOUT_RUNNING	0x00004000	/* tsleep timeout race */
365 #define TDF_TIMEOUT		0x00008000	/* tsleep timeout */
366 #define TDF_INTTHREAD		0x00010000	/* interrupt thread */
367 #define TDF_TSLEEP_DESCHEDULED	0x00020000	/* tsleep core deschedule */
368 #define TDF_BLOCKED		0x00040000	/* Thread is blocked */
369 #define TDF_PANICWARN		0x00080000	/* panic warning in switch */
370 #define TDF_BLOCKQ		0x00100000	/* on block queue */
371 #define TDF_FORCE_SPINPORT	0x00200000
372 #define TDF_EXITING		0x00400000	/* thread exiting */
373 #define TDF_USINGFP		0x00800000	/* thread using fp coproc */
374 #define TDF_KERNELFP		0x01000000	/* kernel using fp coproc */
375 #define TDF_DELAYED_WAKEUP	0x02000000
376 #define TDF_FIXEDCPU		0x04000000	/* running cpu is fixed */
377 #define TDF_USERMODE		0x08000000	/* in or entering user mode */
378 #define TDF_NOFAULT		0x10000000	/* force onfault on fault */
379 
380 #define TDF_MP_STOPREQ		0x00000001	/* suspend_kproc */
381 #define TDF_MP_WAKEREQ		0x00000002	/* resume_kproc */
382 #define TDF_MP_EXITWAIT		0x00000004	/* reaper, see lwp_wait() */
383 #define TDF_MP_EXITSIG		0x00000008	/* reaper, see lwp_wait() */
384 #define TDF_MP_BATCH_DEMARC	0x00000010	/* batch mode handling */
385 #define TDF_MP_DIDYIELD		0x00000020	/* effects scheduling */
386 
387 #define TD_TYPE_GENERIC		0		/* generic thread */
388 #define TD_TYPE_CRYPTO		1		/* crypto thread */
389 #define TD_TYPE_NETISR		2		/* netisr thread */
390 
391 /*
392  * Thread priorities.  Typically only one thread from any given
393  * user process scheduling queue is on the LWKT run queue at a time.
394  * Remember that there is one LWKT run queue per cpu.
395  *
396  * Critical sections are handled by bumping td_pri above TDPRI_MAX, which
397  * causes interrupts to be masked as they occur.  When this occurs a
398  * rollup flag will be set in mycpu->gd_reqflags.
399  */
400 #define TDPRI_IDLE_THREAD	0	/* the idle thread */
401 #define TDPRI_IDLE_WORK		1	/* idle work (page zero, etc) */
402 #define TDPRI_USER_SCHEDULER	2	/* user scheduler helper */
403 #define TDPRI_USER_IDLE		4	/* user scheduler idle */
404 #define TDPRI_USER_NORM		6	/* user scheduler normal */
405 #define TDPRI_USER_REAL		8	/* user scheduler real time */
406 #define TDPRI_KERN_LPSCHED	9	/* (comparison point only) */
407 #define TDPRI_KERN_USER		10	/* kernel / block in syscall */
408 #define TDPRI_KERN_DAEMON	12	/* kernel daemon (pageout, etc) */
409 #define TDPRI_SOFT_NORM		14	/* kernel / normal */
410 #define TDPRI_SOFT_TIMER	16	/* kernel / timer */
411 #define TDPRI_UNUSED19		19
412 #define TDPRI_INT_SUPPORT	20	/* kernel / high priority support */
413 #define TDPRI_INT_LOW		27	/* low priority interrupt */
414 #define TDPRI_INT_MED		28	/* medium priority interrupt */
415 #define TDPRI_INT_HIGH		29	/* high priority interrupt */
416 #define TDPRI_MAX		31
417 
418 #define LWKT_THREAD_STACK	(UPAGES * PAGE_SIZE)
419 
420 #define IN_CRITICAL_SECT(td)	((td)->td_critcount)
421 
422 #ifdef _KERNEL
423 
424 /*
425  * Global tokens
426  */
427 extern struct lwkt_token mp_token;
428 extern struct lwkt_token pmap_token;
429 extern struct lwkt_token dev_token;
430 extern struct lwkt_token vm_token;
431 extern struct lwkt_token vmspace_token;
432 extern struct lwkt_token kvm_token;
433 extern struct lwkt_token sigio_token;
434 extern struct lwkt_token tty_token;
435 extern struct lwkt_token vnode_token;
436 extern struct lwkt_token revoke_token;
437 extern struct lwkt_token kbd_token;
438 extern struct lwkt_token vga_token;
439 
440 /*
441  * Procedures
442  */
443 extern struct thread *lwkt_alloc_thread(struct thread *, int, int, int);
444 extern void lwkt_init_thread(struct thread *, void *, int, int,
445 			     struct globaldata *);
446 extern void lwkt_set_interrupt_support_thread(void);
447 extern void lwkt_set_comm(thread_t, const char *, ...) __printflike(2, 3);
448 extern void lwkt_free_thread(struct thread *);
449 extern void lwkt_gdinit(struct globaldata *);
450 extern void lwkt_switch(void);
451 extern void lwkt_switch_return(struct thread *);
452 extern void lwkt_preempt(thread_t, int);
453 extern void lwkt_schedule(thread_t);
454 extern void lwkt_schedule_noresched(thread_t);
455 extern void lwkt_schedule_self(thread_t);
456 extern void lwkt_deschedule(thread_t);
457 extern void lwkt_deschedule_self(thread_t);
458 extern void lwkt_yield(void);
459 extern void lwkt_yield_quick(void);
460 extern void lwkt_user_yield(void);
461 extern void lwkt_hold(thread_t);
462 extern void lwkt_rele(thread_t);
463 extern void lwkt_passive_release(thread_t);
464 extern void lwkt_maybe_splz(thread_t);
465 
466 extern void lwkt_gettoken(lwkt_token_t);
467 extern void lwkt_gettoken_shared(lwkt_token_t);
468 extern int  lwkt_trytoken(lwkt_token_t);
469 extern void lwkt_reltoken(lwkt_token_t);
470 extern int  lwkt_cnttoken(lwkt_token_t, thread_t);
471 extern int  lwkt_getalltokens(thread_t, int);
472 extern void lwkt_relalltokens(thread_t);
473 extern void lwkt_token_init(lwkt_token_t, const char *);
474 extern void lwkt_token_uninit(lwkt_token_t);
475 
476 extern void lwkt_token_pool_init(void);
477 extern lwkt_token_t lwkt_token_pool_lookup(void *);
478 extern lwkt_token_t lwkt_getpooltoken(void *);
479 extern void lwkt_relpooltoken(void *);
480 
481 extern void lwkt_token_swap(void);
482 
483 extern void lwkt_setpri(thread_t, int);
484 extern void lwkt_setpri_initial(thread_t, int);
485 extern void lwkt_setpri_self(int);
486 extern void lwkt_schedulerclock(thread_t td);
487 extern void lwkt_setcpu_self(struct globaldata *);
488 extern void lwkt_migratecpu(int);
489 
490 extern void lwkt_giveaway(struct thread *);
491 extern void lwkt_acquire(struct thread *);
492 extern int  lwkt_send_ipiq3(struct globaldata *, ipifunc3_t, void *, int);
493 extern int  lwkt_send_ipiq3_passive(struct globaldata *, ipifunc3_t,
494 				    void *, int);
495 extern int  lwkt_send_ipiq3_bycpu(int, ipifunc3_t, void *, int);
496 extern int  lwkt_send_ipiq3_mask(cpumask_t, ipifunc3_t, void *, int);
497 extern void lwkt_wait_ipiq(struct globaldata *, int);
498 extern void lwkt_process_ipiq(void);
499 extern void lwkt_process_ipiq_frame(struct intrframe *);
500 extern void lwkt_smp_stopped(void);
501 extern void lwkt_synchronize_ipiqs(const char *);
502 
503 /* lwkt_cpusync_init() - inline function in sys/thread2.h */
504 extern void lwkt_cpusync_simple(cpumask_t, cpusync_func_t, void *);
505 extern void lwkt_cpusync_interlock(lwkt_cpusync_t);
506 extern void lwkt_cpusync_deinterlock(lwkt_cpusync_t);
507 extern void lwkt_cpusync_quick(lwkt_cpusync_t);
508 
509 extern void crit_panic(void) __dead2;
510 extern struct lwp *lwkt_preempted_proc(void);
511 
512 extern int  lwkt_create (void (*func)(void *), void *, struct thread **,
513 		struct thread *, int, int,
514 		const char *, ...) __printflike(7, 8);
515 extern void lwkt_exit (void) __dead2;
516 extern void lwkt_remove_tdallq (struct thread *);
517 
518 #endif
519 
520 #endif
521 
522