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 * $DragonFly: src/sys/sys/thread.h,v 1.76 2005/12/02 22:02:20 dillon Exp $ 11 */ 12 13 #ifndef _SYS_THREAD_H_ 14 #define _SYS_THREAD_H_ 15 16 #ifndef _SYS_STDINT_H_ 17 #include <sys/stdint.h> /* __int types */ 18 #endif 19 #ifndef _SYS_PARAM_H_ 20 #include <sys/param.h> /* MAXCOMLEN */ 21 #endif 22 #ifndef _SYS_QUEUE_H_ 23 #include <sys/queue.h> /* TAILQ_* macros */ 24 #endif 25 #ifndef _SYS_MSGPORT_H_ 26 #include <sys/msgport.h> /* lwkt_port */ 27 #endif 28 #ifndef _SYS_TIME_H_ 29 #include <sys/time.h> /* struct timeval */ 30 #endif 31 32 struct globaldata; 33 struct lwp; 34 struct proc; 35 struct thread; 36 struct lwkt_queue; 37 struct lwkt_token; 38 struct lwkt_tokref; 39 struct lwkt_wait; 40 struct lwkt_ipiq; 41 struct lwkt_cpu_msg; 42 struct lwkt_cpu_port; 43 struct lwkt_rwlock; 44 struct lwkt_msg; 45 struct lwkt_port; 46 struct lwkt_cpusync; 47 union sysunion; 48 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; 59 60 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue; 61 62 /* 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. 68 */ 69 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) 70 #ifndef _MACHINE_THREAD_H_ 71 #include <machine/thread.h> /* md_thread */ 72 #endif 73 #ifndef _MACHINE_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 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. 85 * 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. 91 * 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. 95 */ 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) */ 100 } lwkt_token; 101 102 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 */ 109 } lwkt_tokref; 110 111 /* 112 * Token state and debug flags. 113 */ 114 #define LWKT_TOKREF_CONTENDED 0x002 /* token ownership contention */ 115 116 /* 117 * The magic number indicates the trans-cpu state of a token reference. 118 * 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(). 123 */ 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) 134 135 /* 136 * Wait structures deal with blocked threads. Due to the way remote cpus 137 * interact with these structures stable storage must be used. 138 */ 139 typedef struct lwkt_wait { 140 lwkt_queue wa_waitq; /* list of waiting threads */ 141 lwkt_token wa_token; /* who currently owns the list */ 142 int wa_gen; 143 int wa_count; 144 } lwkt_wait; 145 146 #define MAXCPUFIFO 16 /* power of 2 */ 147 #define MAXCPUFIFO_MASK (MAXCPUFIFO - 1) 148 #define LWKT_MAXTOKENS 16 /* max tokens beneficially held by thread */ 149 150 /* 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. 154 */ 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); 158 159 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 */ 167 } lwkt_ipiq; 168 169 /* 170 * CPU Synchronization structure. See lwkt_cpusync_start() and 171 * lwkt_cpusync_finish() for more information. 172 */ 173 typedef void (*cpusync_func_t)(lwkt_cpusync_t poll); 174 typedef void (*cpusync_func2_t)(void *data); 175 176 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) */ 180 void *cs_data; 181 int cs_maxcount; 182 volatile int cs_count; 183 cpumask_t cs_mask; 184 }; 185 186 /* 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 190 * blocking. 191 */ 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 */ 197 } lwkt_cpu_msg; 198 199 /* 200 * reader/writer lock 201 */ 202 typedef struct lwkt_rwlock { 203 lwkt_wait rw_wait; 204 thread_t rw_owner; 205 int rw_count; 206 int rw_requests; 207 } lwkt_rwlock; 208 209 #define rw_token rw_wait.wa_token 210 211 /* 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. 217 * 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. 220 */ 221 struct md_intr_info; 222 struct caps_kinfo; 223 224 struct thread { 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 */ 251 #ifdef SMP 252 int td_mpcount; /* MP lock held (count) */ 253 int td_cscount; /* cpu synchronization master */ 254 #else 255 int td_mpcount_unused; /* filler so size matches */ 256 int td_cscount_unused; 257 #endif 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; 269 #endif 270 struct md_thread td_mach; 271 }; 272 273 /* 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. 280 * 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. 284 * 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 288 * queue. 289 */ 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 */ 298 299 #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 */ 314 315 /* 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. 319 * 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. 323 */ 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 */ 338 #define TDPRI_MAX 31 339 340 #define TDPRI_MASK 31 341 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */ 342 343 #ifdef _KERNEL 344 #define LWKT_THREAD_STACK (UPAGES * PAGE_SIZE) 345 #endif 346 347 #define CACHE_NTHREADS 6 348 349 #define IN_CRITICAL_SECT(td) ((td)->td_pri >= TDPRI_CRIT) 350 351 #ifdef _KERNEL 352 353 extern struct vm_zone *thread_zone; 354 355 #endif 356 357 /* 358 * Applies both to the kernel and to liblwkt. 359 */ 360 extern struct thread *lwkt_alloc_thread(struct thread *template, int stksize, 361 int cpu, int flags); 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); 381 382 extern void lwkt_block(lwkt_wait_t w, const char *wmesg, int *gen); 383 extern void lwkt_signal(lwkt_wait_t w, int count); 384 385 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); 396 397 extern void lwkt_token_pool_init(void); 398 extern lwkt_token_t lwkt_token_pool_get(void *ptraddr); 399 400 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); 406 407 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); 411 412 #ifdef SMP 413 414 extern int lwkt_send_ipiq3(struct globaldata *targ, ipifunc3_t func, 415 void *arg1, int arg2); 416 extern int lwkt_send_ipiq3_passive(struct globaldata *targ, ipifunc3_t func, 417 void *arg1, int arg2); 418 extern int lwkt_send_ipiq3_nowait(struct globaldata *targ, ipifunc3_t func, 419 void *arg1, int arg2); 420 extern int lwkt_send_ipiq3_bycpu(int dcpu, ipifunc3_t func, 421 void *arg1, int arg2); 422 extern int lwkt_send_ipiq3_mask(cpumask_t mask, ipifunc3_t func, 423 void *arg1, int arg2); 424 extern void lwkt_wait_ipiq(struct globaldata *targ, int seq); 425 extern int lwkt_seq_ipiq(struct globaldata *targ); 426 extern void lwkt_process_ipiq(void); 427 #ifdef _KERNEL 428 extern void lwkt_process_ipiq_frame(struct intrframe frame); 429 #endif 430 extern void lwkt_smp_stopped(void); 431 432 #endif /* SMP */ 433 434 extern void lwkt_cpusync_simple(cpumask_t mask, cpusync_func_t func, void *data); 435 extern void lwkt_cpusync_fastdata(cpumask_t mask, cpusync_func2_t func, void *data); 436 extern void lwkt_cpusync_start(cpumask_t mask, lwkt_cpusync_t poll); 437 extern void lwkt_cpusync_add(cpumask_t mask, lwkt_cpusync_t poll); 438 extern void lwkt_cpusync_finish(lwkt_cpusync_t poll); 439 440 extern void crit_panic(void); 441 extern struct lwp *lwkt_preempted_proc(void); 442 443 extern int lwkt_create (void (*func)(void *), void *arg, struct thread **ptd, 444 struct thread *template, int tdflags, int cpu, 445 const char *ctl, ...); 446 extern void lwkt_exit (void) __dead2; 447 448 #endif 449 450