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 1.67 2005/07/26 20:53:55 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 proc; 34 struct thread; 35 struct lwkt_queue; 36 struct lwkt_token; 37 struct lwkt_tokref; 38 struct lwkt_wait; 39 struct lwkt_ipiq; 40 struct lwkt_cpu_msg; 41 struct lwkt_cpu_port; 42 struct lwkt_rwlock; 43 struct lwkt_msg; 44 struct lwkt_port; 45 struct lwkt_cpusync; 46 union sysunion; 47 48 typedef struct lwkt_queue *lwkt_queue_t; 49 typedef struct lwkt_token *lwkt_token_t; 50 typedef struct lwkt_tokref *lwkt_tokref_t; 51 typedef struct lwkt_wait *lwkt_wait_t; 52 typedef struct lwkt_cpu_msg *lwkt_cpu_msg_t; 53 typedef struct lwkt_cpu_port *lwkt_cpu_port_t; 54 typedef struct lwkt_rwlock *lwkt_rwlock_t; 55 typedef struct lwkt_ipiq *lwkt_ipiq_t; 56 typedef struct lwkt_cpusync *lwkt_cpusync_t; 57 typedef struct thread *thread_t; 58 59 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue; 60 61 /* 62 * Differentiation between kernel threads and user threads. Userland 63 * programs which want to access to kernel structures have to define 64 * _KERNEL_STRUCTURES. This is a kinda safety valve to prevent badly 65 * written user programs from getting an LWKT thread that is neither the 66 * kernel nor the user version. 67 */ 68 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) 69 #ifndef _MACHINE_THREAD_H_ 70 #include <machine/thread.h> /* md_thread */ 71 #endif 72 #ifndef _MACHINE_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 the thread is 82 * running. If the thread blocks, other threads can run holding the same 83 * tokens. 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. 90 * 91 * Tokens are managed through a helper reference structure, lwkt_tokref, 92 * which is typically declared on the caller's stack. Multiple tokref's 93 * may reference the same token. 94 */ 95 typedef struct lwkt_token { 96 struct globaldata *t_cpu; /* the current owner of the token */ 97 struct globaldata *t_reqcpu; /* requesting cpu */ 98 int t_unused01; /* (used to be generation number) */ 99 } lwkt_token; 100 101 typedef struct lwkt_tokref { 102 lwkt_token_t tr_tok; /* token in question */ 103 __uint32_t tr_magic; /* sanity check */ 104 lwkt_tokref_t tr_next; /* linked list */ 105 lwkt_tokref_t tr_gdreqnext; /* based at gd_tokreqbase */ 106 struct globaldata *tr_reqgd; /* requesting cpu */ 107 int tr_flags; /* token state and debug flags */ 108 } lwkt_tokref; 109 110 /* 111 * Token state and debug flags. 112 */ 113 #define LWKT_TOKREF_CONTENDED 0x002 /* token ownership contention */ 114 115 /* 116 * The magic number indicates the trans-cpu state of a token reference. 117 * 118 * MAGIC1 - token reference is not in transit to another cpu 119 * MAGIC2 - token reference is in transit to another cpu 120 * MAGIC3 - token reference is in a state where it should not be 121 * checked by lwkt_chktoken(). 122 */ 123 #define LWKT_TOKREF_MAGIC1 \ 124 ((__uint32_t)0x544f4b52) /* normal */ 125 #define LWKT_TOKREF_MAGIC2 \ 126 ((__uint32_t)0x544f4b53) /* pending req */ 127 #define LWKT_TOKREF_MAGIC3 \ 128 ((__uint32_t)0x544f4b54) /* indeterminant */ 129 #define LWKT_TOKREF_INIT(tok) \ 130 { tok, LWKT_TOKREF_MAGIC1 } 131 #define LWKT_TOKREF_DECLARE(name, tok) \ 132 lwkt_tokref name = LWKT_TOKREF_INIT(tok) 133 134 /* 135 * Wait structures deal with blocked threads. Due to the way remote cpus 136 * interact with these structures stable storage must be used. 137 */ 138 typedef struct lwkt_wait { 139 lwkt_queue wa_waitq; /* list of waiting threads */ 140 lwkt_token wa_token; /* who currently owns the list */ 141 int wa_gen; 142 int wa_count; 143 } lwkt_wait; 144 145 #define MAXCPUFIFO 16 /* power of 2 */ 146 #define MAXCPUFIFO_MASK (MAXCPUFIFO - 1) 147 #define LWKT_MAXTOKENS 16 /* max tokens beneficially held by thread */ 148 149 /* 150 * Always cast to ipifunc_t when registering an ipi. The actual ipi function 151 * is called with both the data and an interrupt frame, but the ipi function 152 * that is registered might only declare a data argument. 153 */ 154 typedef void (*ipifunc_t)(void *arg); 155 typedef void (*ipifunc2_t)(void *arg, struct intrframe *frame); 156 157 typedef struct lwkt_ipiq { 158 int ip_rindex; /* only written by target cpu */ 159 int ip_xindex; /* written by target, indicates completion */ 160 int ip_windex; /* only written by source cpu */ 161 ipifunc2_t ip_func[MAXCPUFIFO]; 162 void *ip_arg[MAXCPUFIFO]; 163 u_int ip_npoll; /* synchronization to avoid excess IPIs */ 164 } lwkt_ipiq; 165 166 /* 167 * CPU Synchronization structure. See lwkt_cpusync_start() and 168 * lwkt_cpusync_finish() for more information. 169 */ 170 typedef void (*cpusync_func_t)(lwkt_cpusync_t poll); 171 typedef void (*cpusync_func2_t)(void *data); 172 173 struct lwkt_cpusync { 174 cpusync_func_t cs_run_func; /* run (tandem w/ acquire) */ 175 cpusync_func_t cs_fin1_func; /* fin1 (synchronized) */ 176 cpusync_func2_t cs_fin2_func; /* fin2 (tandem w/ release) */ 177 void *cs_data; 178 int cs_maxcount; 179 volatile int cs_count; 180 cpumask_t cs_mask; 181 }; 182 183 /* 184 * The standard message and queue structure used for communications between 185 * cpus. Messages are typically queued via a machine-specific non-linked 186 * FIFO matrix allowing any cpu to send a message to any other cpu without 187 * blocking. 188 */ 189 typedef struct lwkt_cpu_msg { 190 void (*cm_func)(lwkt_cpu_msg_t msg); /* primary dispatch function */ 191 int cm_code; /* request code if applicable */ 192 int cm_cpu; /* reply to cpu */ 193 thread_t cm_originator; /* originating thread for wakeup */ 194 } lwkt_cpu_msg; 195 196 /* 197 * reader/writer lock 198 */ 199 typedef struct lwkt_rwlock { 200 lwkt_wait rw_wait; 201 thread_t rw_owner; 202 int rw_count; 203 int rw_requests; 204 } lwkt_rwlock; 205 206 #define rw_token rw_wait.wa_token 207 208 /* 209 * Thread structure. Note that ownership of a thread structure is special 210 * cased and there is no 'token'. A thread is always owned by the cpu 211 * represented by td_gd, any manipulation of the thread by some other cpu 212 * must be done through cpu_*msg() functions. e.g. you could request 213 * ownership of a thread that way, or hand a thread off to another cpu. 214 * 215 * NOTE: td_pri is bumped by TDPRI_CRIT when entering a critical section, 216 * but this does not effect how the thread is scheduled by LWKT. 217 */ 218 struct md_intr_info; 219 struct caps_kinfo; 220 221 struct thread { 222 TAILQ_ENTRY(thread) td_threadq; 223 TAILQ_ENTRY(thread) td_allq; 224 lwkt_port td_msgport; /* built-in message port for replies */ 225 struct proc *td_proc; /* (optional) associated process */ 226 struct pcb *td_pcb; /* points to pcb and top of kstack */ 227 struct globaldata *td_gd; /* associated with this cpu */ 228 const char *td_wmesg; /* string name for blockage */ 229 void *td_wchan; /* waiting on channel */ 230 int td_pri; /* 0-31, 31=highest priority (note 1) */ 231 int td_flags; /* TDF flags */ 232 int td_wdomain; /* domain for wchan address (typ 0) */ 233 void (*td_preemptable)(struct thread *td, int critpri); 234 void (*td_release)(struct thread *td); 235 union { 236 struct md_intr_info *intdata; 237 } td_info; 238 char *td_kstack; /* kernel stack */ 239 int td_kstack_size; /* size of kernel stack */ 240 char *td_sp; /* kernel stack pointer for LWKT restore */ 241 void (*td_switch)(struct thread *ntd); 242 lwkt_wait_t td_wait; /* thread sitting on wait structure */ 243 __uint64_t td_uticks; /* Statclock hits in user mode (uS) */ 244 __uint64_t td_sticks; /* Statclock hits in system mode (uS) */ 245 __uint64_t td_iticks; /* Statclock hits processing intr (uS) */ 246 int td_locks; /* lockmgr lock debugging YYY */ 247 int td_refs; /* hold position in gd_tdallq / hold free */ 248 int td_nest_count; /* prevent splz nesting */ 249 #ifdef SMP 250 int td_mpcount; /* MP lock held (count) */ 251 int td_cscount; /* cpu synchronization master */ 252 #else 253 int td_mpcount_unused; /* filler so size matches */ 254 int td_cscount_unused; 255 #endif 256 struct timeval td_start; /* start time for a thread/process */ 257 char td_comm[MAXCOMLEN+1]; /* typ 16+1 bytes */ 258 struct thread *td_preempted; /* we preempted this thread */ 259 struct caps_kinfo *td_caps; /* list of client and server registrations */ 260 lwkt_tokref_t td_toks; /* tokens beneficially held */ 261 #ifdef DEBUG_CRIT_SECTIONS 262 #define CRIT_DEBUG_ARRAY_SIZE 32 263 #define CRIT_DEBUG_ARRAY_MASK (CRIT_DEBUG_ARRAY_SIZE - 1) 264 const char *td_crit_debug_array[CRIT_DEBUG_ARRAY_SIZE]; 265 int td_crit_debug_index; 266 int td_in_crit_report; 267 #endif 268 struct md_thread td_mach; 269 }; 270 271 /* 272 * Thread flags. Note that TDF_RUNNING is cleared on the old thread after 273 * we switch to the new one, which is necessary because LWKTs don't need 274 * to hold the BGL. This flag is used by the exit code and the managed 275 * thread migration code. 276 * 277 * LWKT threads stay on their (per-cpu) run queue while running, not to 278 * be confused with user processes which are removed from the user scheduling 279 * run queue while actually running. 280 */ 281 #define TDF_RUNNING 0x0001 /* thread still active */ 282 #define TDF_RUNQ 0x0002 /* on an LWKT run queue */ 283 #define TDF_PREEMPT_LOCK 0x0004 /* I have been preempted */ 284 #define TDF_PREEMPT_DONE 0x0008 /* acknowledge preemption complete */ 285 #define TDF_IDLE_NOHLT 0x0010 /* we need to spin */ 286 #define TDF_MIGRATING 0x0020 /* thread is being migrated */ 287 #define TDF_SINTR 0x0040 /* interruptability hint for 'ps' */ 288 289 #define TDF_SYSTHREAD 0x0100 /* system thread */ 290 #define TDF_ALLOCATED_THREAD 0x0200 /* zalloc allocated thread */ 291 #define TDF_ALLOCATED_STACK 0x0400 /* zalloc allocated stack */ 292 #define TDF_VERBOSE 0x0800 /* verbose on exit */ 293 #define TDF_DEADLKTREAT 0x1000 /* special lockmgr deadlock treatment */ 294 #define TDF_STOPREQ 0x2000 /* suspend_kproc */ 295 #define TDF_WAKEREQ 0x4000 /* resume_kproc */ 296 #define TDF_TIMEOUT 0x8000 /* tsleep timeout */ 297 #define TDF_INTTHREAD 0x00010000 /* interrupt thread */ 298 #define TDF_NORESCHED 0x00020000 /* Do not reschedule on wake */ 299 #define TDF_BLOCKED 0x00040000 /* Thread is blocked */ 300 #define TDF_PANICWARN 0x00080000 /* panic warning in switch */ 301 302 /* 303 * Thread priorities. Typically only one thread from any given 304 * user process scheduling queue is on the LWKT run queue at a time. 305 * Remember that there is one LWKT run queue per cpu. 306 * 307 * Critical sections are handled by bumping td_pri above TDPRI_MAX, which 308 * causes interrupts to be masked as they occur. When this occurs a 309 * rollup flag will be set in mycpu->gd_reqflags. 310 */ 311 #define TDPRI_IDLE_THREAD 0 /* the idle thread */ 312 #define TDPRI_USER_IDLE 4 /* user scheduler idle */ 313 #define TDPRI_USER_NORM 6 /* user scheduler normal */ 314 #define TDPRI_USER_REAL 8 /* user scheduler real time */ 315 #define TDPRI_KERN_LPSCHED 9 /* scheduler helper for userland sch */ 316 #define TDPRI_KERN_USER 10 /* kernel / block in syscall */ 317 #define TDPRI_KERN_DAEMON 12 /* kernel daemon (pageout, etc) */ 318 #define TDPRI_SOFT_NORM 14 /* kernel / normal */ 319 #define TDPRI_SOFT_TIMER 16 /* kernel / timer */ 320 #define TDPRI_EXITING 19 /* exiting thread */ 321 #define TDPRI_INT_SUPPORT 20 /* kernel / high priority support */ 322 #define TDPRI_INT_LOW 27 /* low priority interrupt */ 323 #define TDPRI_INT_MED 28 /* medium priority interrupt */ 324 #define TDPRI_INT_HIGH 29 /* high priority interrupt */ 325 #define TDPRI_MAX 31 326 327 #define TDPRI_MASK 31 328 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */ 329 330 #ifdef _KERNEL 331 #define LWKT_THREAD_STACK (UPAGES * PAGE_SIZE) 332 #endif 333 334 #define CACHE_NTHREADS 6 335 336 #define IN_CRITICAL_SECT(td) ((td)->td_pri >= TDPRI_CRIT) 337 338 #ifdef _KERNEL 339 340 extern struct vm_zone *thread_zone; 341 342 #endif 343 344 /* 345 * Applies both to the kernel and to liblwkt. 346 */ 347 extern struct thread *lwkt_alloc_thread(struct thread *template, int stksize, 348 int cpu); 349 extern void lwkt_init_thread(struct thread *td, void *stack, int stksize, 350 int flags, struct globaldata *gd); 351 extern void lwkt_set_comm(thread_t td, const char *ctl, ...); 352 extern void lwkt_wait_free(struct thread *td); 353 extern void lwkt_free_thread(struct thread *td); 354 extern void lwkt_wait_init(struct lwkt_wait *w); 355 extern void lwkt_gdinit(struct globaldata *gd); 356 extern void lwkt_switch(void); 357 extern void lwkt_preempt(thread_t ntd, int critpri); 358 extern void lwkt_schedule(thread_t td); 359 extern void lwkt_schedule_self(thread_t td); 360 extern void lwkt_deschedule(thread_t td); 361 extern void lwkt_deschedule_self(thread_t td); 362 extern void lwkt_acquire(thread_t td); 363 extern void lwkt_yield(void); 364 extern void lwkt_yield_quick(void); 365 extern void lwkt_token_wait(void); 366 extern void lwkt_hold(thread_t td); 367 extern void lwkt_rele(thread_t td); 368 369 extern void lwkt_block(lwkt_wait_t w, const char *wmesg, int *gen); 370 extern void lwkt_signal(lwkt_wait_t w, int count); 371 372 extern int lwkt_havetoken(lwkt_token_t tok); 373 extern int lwkt_havetokref(lwkt_tokref_t xref); 374 extern void lwkt_gettoken(lwkt_tokref_t ref, lwkt_token_t tok); 375 extern int lwkt_trytoken(lwkt_tokref_t ref, lwkt_token_t tok); 376 extern void lwkt_gettokref(lwkt_tokref_t ref); 377 extern int lwkt_trytokref(lwkt_tokref_t ref); 378 extern void lwkt_reltoken(lwkt_tokref_t ref); 379 extern int lwkt_chktokens(thread_t td); 380 extern void lwkt_drain_token_requests(void); 381 extern void lwkt_token_init(lwkt_token_t tok); 382 extern void lwkt_token_uninit(lwkt_token_t tok); 383 384 extern void lwkt_token_pool_init(void); 385 extern lwkt_token_t lwkt_token_pool_get(void *ptraddr); 386 387 extern void lwkt_rwlock_init(lwkt_rwlock_t lock); 388 extern void lwkt_rwlock_uninit(lwkt_rwlock_t lock); 389 extern void lwkt_exlock(lwkt_rwlock_t lock, const char *wmesg); 390 extern void lwkt_shlock(lwkt_rwlock_t lock, const char *wmesg); 391 extern void lwkt_exunlock(lwkt_rwlock_t lock); 392 extern void lwkt_shunlock(lwkt_rwlock_t lock); 393 394 extern void lwkt_setpri(thread_t td, int pri); 395 extern void lwkt_setpri_self(int pri); 396 extern int lwkt_checkpri_self(void); 397 extern void lwkt_setcpu_self(struct globaldata *rgd); 398 extern int lwkt_send_ipiq(struct globaldata *targ, ipifunc_t func, void *arg); 399 extern int lwkt_send_ipiq_passive(struct globaldata *targ, ipifunc_t func, void *arg); 400 extern int lwkt_send_ipiq_nowait(struct globaldata *targ, ipifunc_t func, void *arg); 401 extern int lwkt_send_ipiq_bycpu(int dcpu, ipifunc_t func, void *arg); 402 extern int lwkt_send_ipiq_mask(cpumask_t mask, ipifunc_t func, void *arg); 403 extern void lwkt_wait_ipiq(struct globaldata *targ, int seq); 404 extern int lwkt_seq_ipiq(struct globaldata *targ); 405 extern void lwkt_process_ipiq(void); 406 #ifdef _KERNEL 407 extern void lwkt_process_ipiq_frame(struct intrframe frame); 408 #endif 409 extern void lwkt_cpusync_simple(cpumask_t mask, cpusync_func_t func, void *data); 410 extern void lwkt_cpusync_fastdata(cpumask_t mask, cpusync_func2_t func, void *data); 411 extern void lwkt_cpusync_start(cpumask_t mask, lwkt_cpusync_t poll); 412 extern void lwkt_cpusync_add(cpumask_t mask, lwkt_cpusync_t poll); 413 extern void lwkt_cpusync_finish(lwkt_cpusync_t poll); 414 extern void lwkt_smp_stopped(void); 415 extern void crit_panic(void); 416 extern struct proc *lwkt_preempted_proc(void); 417 418 extern int lwkt_create (void (*func)(void *), void *arg, struct thread **ptd, 419 struct thread *template, int tdflags, int cpu, 420 const char *ctl, ...); 421 extern void lwkt_exit (void) __dead2; 422 423 #endif 424 425