4 * Implements the architecture independant portion of the LWKT
7 * Types which must already be defined when this header is included by
8 * userland: struct md_thread
10 * $DragonFly: src/sys/sys/thread.h,v 1.77 2006/01/31 19:05:44 dillon Exp $
13 #ifndef _SYS_THREAD_H_
14 #define _SYS_THREAD_H_
16 #ifndef _SYS_STDINT_H_
17 #include <sys/stdint.h> /* __int types */
20 #include <sys/param.h> /* MAXCOMLEN */
23 #include <sys/queue.h> /* TAILQ_* macros */
25 #ifndef _SYS_MSGPORT_H_
26 #include <sys/msgport.h> /* lwkt_port */
29 #include <sys/time.h> /* struct timeval */
49 typedef struct lwkt_queue
*lwkt_queue_t
;
50 typedef struct lwkt_token
*lwkt_token_t
;
51 typedef struct lwkt_tokref
*lwkt_tokref_t
;
52 typedef struct lwkt_wait
*lwkt_wait_t
;
53 typedef struct lwkt_cpu_msg
*lwkt_cpu_msg_t
;
54 typedef struct lwkt_cpu_port
*lwkt_cpu_port_t
;
55 typedef struct lwkt_rwlock
*lwkt_rwlock_t
;
56 typedef struct lwkt_ipiq
*lwkt_ipiq_t
;
57 typedef struct lwkt_cpusync
*lwkt_cpusync_t
;
58 typedef struct thread
*thread_t
;
60 typedef TAILQ_HEAD(lwkt_queue
, thread
) lwkt_queue
;
63 * Differentiation between kernel threads and user threads. Userland
64 * programs which want to access to kernel structures have to define
65 * _KERNEL_STRUCTURES. This is a kinda safety valve to prevent badly
66 * written user programs from getting an LWKT thread that is neither the
67 * kernel nor the user version.
69 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
70 #ifndef _MACHINE_THREAD_H_
71 #include <machine/thread.h> /* md_thread */
73 #ifndef _MACHINE_FRAME_H_
74 #include <machine/frame.h>
81 * Tokens are used to serialize access to information. They are 'soft'
82 * serialization entities that only stay in effect while the thread is
83 * running. If the thread blocks, other threads can run holding the same
84 * tokens. The tokens are reacquired when the original thread resumes.
86 * A thread can depend on its serialization remaining intact through a
87 * preemption. An interrupt which attempts to use the same token as the
88 * thread being preempted will reschedule itself for non-preemptive
89 * operation, so the new token code is capable of interlocking against
90 * interrupts as well as other cpus.
92 * Tokens are managed through a helper reference structure, lwkt_tokref,
93 * which is typically declared on the caller's stack. Multiple tokref's
94 * may reference the same token.
96 typedef struct lwkt_token
{
97 struct globaldata
*t_cpu
; /* the current owner of the token */
98 struct globaldata
*t_reqcpu
; /* requesting cpu */
99 int t_unused01
; /* (used to be generation number) */
102 typedef struct lwkt_tokref
{
103 lwkt_token_t tr_tok
; /* token in question */
104 __uint32_t tr_magic
; /* sanity check */
105 lwkt_tokref_t tr_next
; /* linked list */
106 lwkt_tokref_t tr_gdreqnext
; /* based at gd_tokreqbase */
107 struct globaldata
*tr_reqgd
; /* requesting cpu */
108 int tr_flags
; /* token state and debug flags */
112 * Token state and debug flags.
114 #define LWKT_TOKREF_CONTENDED 0x002 /* token ownership contention */
117 * The magic number indicates the trans-cpu state of a token reference.
119 * MAGIC1 - token reference is not in transit to another cpu
120 * MAGIC2 - token reference is in transit to another cpu
121 * MAGIC3 - token reference is in a state where it should not be
122 * checked by lwkt_chktoken().
124 #define LWKT_TOKREF_MAGIC1 \
125 ((__uint32_t)0x544f4b52) /* normal */
126 #define LWKT_TOKREF_MAGIC2 \
127 ((__uint32_t)0x544f4b53) /* pending req */
128 #define LWKT_TOKREF_MAGIC3 \
129 ((__uint32_t)0x544f4b54) /* indeterminant */
130 #define LWKT_TOKREF_INIT(tok) \
131 { tok, LWKT_TOKREF_MAGIC1 }
132 #define LWKT_TOKREF_DECLARE(name, tok) \
133 lwkt_tokref name = LWKT_TOKREF_INIT(tok)
136 * Wait structures deal with blocked threads. Due to the way remote cpus
137 * interact with these structures stable storage must be used.
139 typedef struct lwkt_wait
{
140 lwkt_queue wa_waitq
; /* list of waiting threads */
141 lwkt_token wa_token
; /* who currently owns the list */
146 #define MAXCPUFIFO 16 /* power of 2 */
147 #define MAXCPUFIFO_MASK (MAXCPUFIFO - 1)
148 #define LWKT_MAXTOKENS 16 /* max tokens beneficially held by thread */
151 * Always cast to ipifunc_t when registering an ipi. The actual ipi function
152 * is called with both the data and an interrupt frame, but the ipi function
153 * that is registered might only declare a data argument.
155 typedef void (*ipifunc1_t
)(void *arg
);
156 typedef void (*ipifunc2_t
)(void *arg
, int arg2
);
157 typedef void (*ipifunc3_t
)(void *arg
, int arg2
, struct intrframe
*frame
);
159 typedef struct lwkt_ipiq
{
160 int ip_rindex
; /* only written by target cpu */
161 int ip_xindex
; /* written by target, indicates completion */
162 int ip_windex
; /* only written by source cpu */
163 ipifunc3_t ip_func
[MAXCPUFIFO
];
164 void *ip_arg1
[MAXCPUFIFO
];
165 int ip_arg2
[MAXCPUFIFO
];
166 u_int ip_npoll
; /* synchronization to avoid excess IPIs */
170 * CPU Synchronization structure. See lwkt_cpusync_start() and
171 * lwkt_cpusync_finish() for more information.
173 typedef void (*cpusync_func_t
)(lwkt_cpusync_t poll
);
174 typedef void (*cpusync_func2_t
)(void *data
);
176 struct lwkt_cpusync
{
177 cpusync_func_t cs_run_func
; /* run (tandem w/ acquire) */
178 cpusync_func_t cs_fin1_func
; /* fin1 (synchronized) */
179 cpusync_func2_t cs_fin2_func
; /* fin2 (tandem w/ release) */
182 volatile int cs_count
;
187 * The standard message and queue structure used for communications between
188 * cpus. Messages are typically queued via a machine-specific non-linked
189 * FIFO matrix allowing any cpu to send a message to any other cpu without
192 typedef struct lwkt_cpu_msg
{
193 void (*cm_func
)(lwkt_cpu_msg_t msg
); /* primary dispatch function */
194 int cm_code
; /* request code if applicable */
195 int cm_cpu
; /* reply to cpu */
196 thread_t cm_originator
; /* originating thread for wakeup */
202 typedef struct lwkt_rwlock
{
209 #define rw_token rw_wait.wa_token
212 * Thread structure. Note that ownership of a thread structure is special
213 * cased and there is no 'token'. A thread is always owned by the cpu
214 * represented by td_gd, any manipulation of the thread by some other cpu
215 * must be done through cpu_*msg() functions. e.g. you could request
216 * ownership of a thread that way, or hand a thread off to another cpu.
218 * NOTE: td_pri is bumped by TDPRI_CRIT when entering a critical section,
219 * but this does not effect how the thread is scheduled by LWKT.
225 TAILQ_ENTRY(thread
) td_threadq
;
226 TAILQ_ENTRY(thread
) td_allq
;
227 lwkt_port td_msgport
; /* built-in message port for replies */
228 struct lwp
*td_lwp
; /* (optional) associated lwp */
229 struct proc
*td_proc
; /* (optional) associated process */
230 struct pcb
*td_pcb
; /* points to pcb and top of kstack */
231 struct globaldata
*td_gd
; /* associated with this cpu */
232 const char *td_wmesg
; /* string name for blockage */
233 void *td_wchan
; /* waiting on channel */
234 int td_pri
; /* 0-31, 31=highest priority (note 1) */
235 int td_flags
; /* TDF flags */
236 int td_wdomain
; /* domain for wchan address (typ 0) */
237 void (*td_preemptable
)(struct thread
*td
, int critpri
);
238 void (*td_release
)(struct thread
*td
);
239 char *td_kstack
; /* kernel stack */
240 int td_kstack_size
; /* size of kernel stack */
241 char *td_sp
; /* kernel stack pointer for LWKT restore */
242 void (*td_switch
)(struct thread
*ntd
);
243 lwkt_wait_t td_wait
; /* thread sitting on wait structure */
244 __uint64_t td_uticks
; /* Statclock hits in user mode (uS) */
245 __uint64_t td_sticks
; /* Statclock hits in system mode (uS) */
246 __uint64_t td_iticks
; /* Statclock hits processing intr (uS) */
247 int td_locks
; /* lockmgr lock debugging */
248 int td_spinlocks
; /* spinlock debugging */
249 int td_refs
; /* hold position in gd_tdallq / hold free */
250 int td_nest_count
; /* prevent splz nesting */
252 int td_mpcount
; /* MP lock held (count) */
253 int td_cscount
; /* cpu synchronization master */
255 int td_mpcount_unused
; /* filler so size matches */
256 int td_cscount_unused
;
258 struct timeval td_start
; /* start time for a thread/process */
259 char td_comm
[MAXCOMLEN
+1]; /* typ 16+1 bytes */
260 struct thread
*td_preempted
; /* we preempted this thread */
261 struct caps_kinfo
*td_caps
; /* list of client and server registrations */
262 lwkt_tokref_t td_toks
; /* tokens beneficially held */
263 #ifdef DEBUG_CRIT_SECTIONS
264 #define CRIT_DEBUG_ARRAY_SIZE 32
265 #define CRIT_DEBUG_ARRAY_MASK (CRIT_DEBUG_ARRAY_SIZE - 1)
266 const char *td_crit_debug_array
[CRIT_DEBUG_ARRAY_SIZE
];
267 int td_crit_debug_index
;
268 int td_in_crit_report
;
270 struct md_thread td_mach
;
274 * Thread flags. Note that TDF_RUNNING is cleared on the old thread after
275 * we switch to the new one, which is necessary because LWKTs don't need
276 * to hold the BGL. This flag is used by the exit code and the managed
277 * thread migration code. Note in addition that preemption will cause
278 * TDF_RUNNING to be cleared temporarily, so any code checking TDF_RUNNING
279 * must also check TDF_PREEMPT_LOCK.
281 * LWKT threads stay on their (per-cpu) run queue while running, not to
282 * be confused with user processes which are removed from the user scheduling
283 * run queue while actually running.
285 * td_threadq can represent the thread on one of three queues... the LWKT
286 * run queue, a tsleep queue, or an lwkt blocking queue. The LWKT subsystem
287 * does not allow a thread to be scheduled if it already resides on some
290 #define TDF_RUNNING 0x0001 /* thread still active */
291 #define TDF_RUNQ 0x0002 /* on an LWKT run queue */
292 #define TDF_PREEMPT_LOCK 0x0004 /* I have been preempted */
293 #define TDF_PREEMPT_DONE 0x0008 /* acknowledge preemption complete */
294 #define TDF_IDLE_NOHLT 0x0010 /* we need to spin */
295 #define TDF_MIGRATING 0x0020 /* thread is being migrated */
296 #define TDF_SINTR 0x0040 /* interruptability hint for 'ps' */
297 #define TDF_TSLEEPQ 0x0080 /* on a tsleep wait queue */
299 #define TDF_SYSTHREAD 0x0100 /* system thread */
300 #define TDF_ALLOCATED_THREAD 0x0200 /* zalloc allocated thread */
301 #define TDF_ALLOCATED_STACK 0x0400 /* zalloc allocated stack */
302 #define TDF_VERBOSE 0x0800 /* verbose on exit */
303 #define TDF_DEADLKTREAT 0x1000 /* special lockmgr deadlock treatment */
304 #define TDF_STOPREQ 0x2000 /* suspend_kproc */
305 #define TDF_WAKEREQ 0x4000 /* resume_kproc */
306 #define TDF_TIMEOUT 0x8000 /* tsleep timeout */
307 #define TDF_INTTHREAD 0x00010000 /* interrupt thread */
308 #define TDF_NORESCHED 0x00020000 /* Do not reschedule on wake */
309 #define TDF_BLOCKED 0x00040000 /* Thread is blocked */
310 #define TDF_PANICWARN 0x00080000 /* panic warning in switch */
311 #define TDF_BLOCKQ 0x00100000 /* on block queue */
312 #define TDF_MPSAFE 0x00200000 /* (thread creation) */
313 #define TDF_EXITING 0x00400000 /* thread exiting */
316 * Thread priorities. Typically only one thread from any given
317 * user process scheduling queue is on the LWKT run queue at a time.
318 * Remember that there is one LWKT run queue per cpu.
320 * Critical sections are handled by bumping td_pri above TDPRI_MAX, which
321 * causes interrupts to be masked as they occur. When this occurs a
322 * rollup flag will be set in mycpu->gd_reqflags.
324 #define TDPRI_IDLE_THREAD 0 /* the idle thread */
325 #define TDPRI_USER_IDLE 4 /* user scheduler idle */
326 #define TDPRI_USER_NORM 6 /* user scheduler normal */
327 #define TDPRI_USER_REAL 8 /* user scheduler real time */
328 #define TDPRI_KERN_LPSCHED 9 /* scheduler helper for userland sch */
329 #define TDPRI_KERN_USER 10 /* kernel / block in syscall */
330 #define TDPRI_KERN_DAEMON 12 /* kernel daemon (pageout, etc) */
331 #define TDPRI_SOFT_NORM 14 /* kernel / normal */
332 #define TDPRI_SOFT_TIMER 16 /* kernel / timer */
333 #define TDPRI_EXITING 19 /* exiting thread */
334 #define TDPRI_INT_SUPPORT 20 /* kernel / high priority support */
335 #define TDPRI_INT_LOW 27 /* low priority interrupt */
336 #define TDPRI_INT_MED 28 /* medium priority interrupt */
337 #define TDPRI_INT_HIGH 29 /* high priority interrupt */
340 #define TDPRI_MASK 31
341 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */
344 #define LWKT_THREAD_STACK (UPAGES * PAGE_SIZE)
347 #define CACHE_NTHREADS 6
349 #define IN_CRITICAL_SECT(td) ((td)->td_pri >= TDPRI_CRIT)
353 extern struct vm_zone
*thread_zone
;
358 * Applies both to the kernel and to liblwkt.
360 extern struct thread
*lwkt_alloc_thread(struct thread
*template, int stksize
,
362 extern void lwkt_init_thread(struct thread
*td
, void *stack
, int stksize
,
363 int flags
, struct globaldata
*gd
);
364 extern void lwkt_set_comm(thread_t td
, const char *ctl
, ...);
365 extern void lwkt_wait_free(struct thread
*td
);
366 extern void lwkt_free_thread(struct thread
*td
);
367 extern void lwkt_wait_init(struct lwkt_wait
*w
);
368 extern void lwkt_gdinit(struct globaldata
*gd
);
369 extern void lwkt_switch(void);
370 extern void lwkt_preempt(thread_t ntd
, int critpri
);
371 extern void lwkt_schedule(thread_t td
);
372 extern void lwkt_schedule_self(thread_t td
);
373 extern void lwkt_deschedule(thread_t td
);
374 extern void lwkt_deschedule_self(thread_t td
);
375 extern void lwkt_acquire(thread_t td
);
376 extern void lwkt_yield(void);
377 extern void lwkt_yield_quick(void);
378 extern void lwkt_token_wait(void);
379 extern void lwkt_hold(thread_t td
);
380 extern void lwkt_rele(thread_t td
);
382 extern void lwkt_block(lwkt_wait_t w
, const char *wmesg
, int *gen
);
383 extern void lwkt_signal(lwkt_wait_t w
, int count
);
385 extern int lwkt_havetoken(lwkt_token_t tok
);
386 extern int lwkt_havetokref(lwkt_tokref_t xref
);
387 extern void lwkt_gettoken(lwkt_tokref_t ref
, lwkt_token_t tok
);
388 extern int lwkt_trytoken(lwkt_tokref_t ref
, lwkt_token_t tok
);
389 extern void lwkt_gettokref(lwkt_tokref_t ref
);
390 extern int lwkt_trytokref(lwkt_tokref_t ref
);
391 extern void lwkt_reltoken(lwkt_tokref_t ref
);
392 extern int lwkt_chktokens(thread_t td
);
393 extern void lwkt_drain_token_requests(void);
394 extern void lwkt_token_init(lwkt_token_t tok
);
395 extern void lwkt_token_uninit(lwkt_token_t tok
);
397 extern void lwkt_token_pool_init(void);
398 extern lwkt_token_t
lwkt_token_pool_get(void *ptraddr
);
400 extern void lwkt_rwlock_init(lwkt_rwlock_t lock
);
401 extern void lwkt_rwlock_uninit(lwkt_rwlock_t lock
);
402 extern void lwkt_exlock(lwkt_rwlock_t lock
, const char *wmesg
);
403 extern void lwkt_shlock(lwkt_rwlock_t lock
, const char *wmesg
);
404 extern void lwkt_exunlock(lwkt_rwlock_t lock
);
405 extern void lwkt_shunlock(lwkt_rwlock_t lock
);
407 extern void lwkt_setpri(thread_t td
, int pri
);
408 extern void lwkt_setpri_self(int pri
);
409 extern int lwkt_checkpri_self(void);
410 extern void lwkt_setcpu_self(struct globaldata
*rgd
);
411 extern void lwkt_migratecpu(int cpuid
);
415 extern int lwkt_send_ipiq3(struct globaldata
*targ
, ipifunc3_t func
,
416 void *arg1
, int arg2
);
417 extern int lwkt_send_ipiq3_passive(struct globaldata
*targ
, ipifunc3_t func
,
418 void *arg1
, int arg2
);
419 extern int lwkt_send_ipiq3_nowait(struct globaldata
*targ
, ipifunc3_t func
,
420 void *arg1
, int arg2
);
421 extern int lwkt_send_ipiq3_bycpu(int dcpu
, ipifunc3_t func
,
422 void *arg1
, int arg2
);
423 extern int lwkt_send_ipiq3_mask(cpumask_t mask
, ipifunc3_t func
,
424 void *arg1
, int arg2
);
425 extern void lwkt_wait_ipiq(struct globaldata
*targ
, int seq
);
426 extern int lwkt_seq_ipiq(struct globaldata
*targ
);
427 extern void lwkt_process_ipiq(void);
429 extern void lwkt_process_ipiq_frame(struct intrframe frame
);
431 extern void lwkt_smp_stopped(void);
435 extern void lwkt_cpusync_simple(cpumask_t mask
, cpusync_func_t func
, void *data
);
436 extern void lwkt_cpusync_fastdata(cpumask_t mask
, cpusync_func2_t func
, void *data
);
437 extern void lwkt_cpusync_start(cpumask_t mask
, lwkt_cpusync_t poll
);
438 extern void lwkt_cpusync_add(cpumask_t mask
, lwkt_cpusync_t poll
);
439 extern void lwkt_cpusync_finish(lwkt_cpusync_t poll
);
441 extern void crit_panic(void);
442 extern struct lwp
*lwkt_preempted_proc(void);
444 extern int lwkt_create (void (*func
)(void *), void *arg
, struct thread
**ptd
,
445 struct thread
*template, int tdflags
, int cpu
,
446 const char *ctl
, ...);
447 extern void lwkt_exit (void) __dead2
;