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 1.57 2004/07/29 08:55:02 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 } lwkt_tokref; 108 109 #define LWKT_TOKREF_MAGIC1 \ 110 ((__uint32_t)0x544f4b52) /* normal */ 111 #define LWKT_TOKREF_MAGIC2 \ 112 ((__uint32_t)0x544f4b53) /* pending req */ 113 #define LWKT_TOKREF_INIT(tok) \ 114 { tok, LWKT_TOKREF_MAGIC1 } 115 #define LWKT_TOKREF_DECLARE(name, tok) \ 116 lwkt_tokref name = LWKT_TOKREF_INIT(tok) 117 118 /* 119 * Wait structures deal with blocked threads. Due to the way remote cpus 120 * interact with these structures stable storage must be used. 121 */ 122 typedef struct lwkt_wait { 123 lwkt_queue wa_waitq; /* list of waiting threads */ 124 lwkt_token wa_token; /* who currently owns the list */ 125 int wa_gen; 126 int wa_count; 127 } lwkt_wait; 128 129 #define MAXCPUFIFO 16 /* power of 2 */ 130 #define MAXCPUFIFO_MASK (MAXCPUFIFO - 1) 131 #define LWKT_MAXTOKENS 16 /* max tokens beneficially held by thread */ 132 133 /* 134 * Always cast to ipifunc_t when registering an ipi. The actual ipi function 135 * is called with both the data and an interrupt frame, but the ipi function 136 * that is registered might only declare a data argument. 137 */ 138 typedef void (*ipifunc_t)(void *arg); 139 typedef void (*ipifunc2_t)(void *arg, struct intrframe *frame); 140 141 typedef struct lwkt_ipiq { 142 int ip_rindex; /* only written by target cpu */ 143 int ip_xindex; /* written by target, indicates completion */ 144 int ip_windex; /* only written by source cpu */ 145 ipifunc2_t ip_func[MAXCPUFIFO]; 146 void *ip_arg[MAXCPUFIFO]; 147 int ip_npoll; 148 } lwkt_ipiq; 149 150 /* 151 * CPU Synchronization structure. See lwkt_cpusync_start() and 152 * lwkt_cpusync_finish() for more information. 153 */ 154 typedef void (*cpusync_func_t)(lwkt_cpusync_t poll); 155 typedef void (*cpusync_func2_t)(void *data); 156 157 struct lwkt_cpusync { 158 cpusync_func_t cs_run_func; /* run (tandem w/ acquire) */ 159 cpusync_func_t cs_fin1_func; /* fin1 (synchronized) */ 160 cpusync_func2_t cs_fin2_func; /* fin2 (tandem w/ release) */ 161 void *cs_data; 162 int cs_maxcount; 163 volatile int cs_count; 164 cpumask_t cs_mask; 165 }; 166 167 /* 168 * The standard message and queue structure used for communications between 169 * cpus. Messages are typically queued via a machine-specific non-linked 170 * FIFO matrix allowing any cpu to send a message to any other cpu without 171 * blocking. 172 */ 173 typedef struct lwkt_cpu_msg { 174 void (*cm_func)(lwkt_cpu_msg_t msg); /* primary dispatch function */ 175 int cm_code; /* request code if applicable */ 176 int cm_cpu; /* reply to cpu */ 177 thread_t cm_originator; /* originating thread for wakeup */ 178 } lwkt_cpu_msg; 179 180 /* 181 * reader/writer lock 182 */ 183 typedef struct lwkt_rwlock { 184 lwkt_wait rw_wait; 185 thread_t rw_owner; 186 int rw_count; 187 int rw_requests; 188 } lwkt_rwlock; 189 190 #define rw_token rw_wait.wa_token 191 192 /* 193 * Thread structure. Note that ownership of a thread structure is special 194 * cased and there is no 'token'. A thread is always owned by the cpu 195 * represented by td_gd, any manipulation of the thread by some other cpu 196 * must be done through cpu_*msg() functions. e.g. you could request 197 * ownership of a thread that way, or hand a thread off to another cpu. 198 * 199 * NOTE: td_pri is bumped by TDPRI_CRIT when entering a critical section, 200 * but this does not effect how the thread is scheduled by LWKT. 201 */ 202 struct md_intr_info; 203 struct caps_kinfo; 204 205 struct thread { 206 TAILQ_ENTRY(thread) td_threadq; 207 TAILQ_ENTRY(thread) td_allq; 208 lwkt_port td_msgport; /* built-in message port for replies */ 209 struct proc *td_proc; /* (optional) associated process */ 210 struct pcb *td_pcb; /* points to pcb and top of kstack */ 211 struct globaldata *td_gd; /* associated with this cpu */ 212 const char *td_wmesg; /* string name for blockage */ 213 void *td_wchan; /* waiting on channel */ 214 int td_pri; /* 0-31, 31=highest priority (note 1) */ 215 int td_flags; /* TDF flags */ 216 int td_gen; /* wait queue chasing generation number */ 217 /* maybe preempt */ 218 void (*td_preemptable)(struct thread *td, int critpri); 219 void (*td_release)(struct thread *td); 220 union { 221 struct md_intr_info *intdata; 222 } td_info; 223 char *td_kstack; /* kernel stack */ 224 int td_kstack_size; /* size of kernel stack */ 225 char *td_sp; /* kernel stack pointer for LWKT restore */ 226 void (*td_switch)(struct thread *ntd); 227 lwkt_wait_t td_wait; /* thread sitting on wait structure */ 228 __uint64_t td_uticks; /* Statclock hits in user mode (uS) */ 229 __uint64_t td_sticks; /* Statclock hits in system mode (uS) */ 230 __uint64_t td_iticks; /* Statclock hits processing intr (uS) */ 231 int td_locks; /* lockmgr lock debugging YYY */ 232 int td_refs; /* hold position in gd_tdallq / hold free */ 233 int td_nest_count; /* prevent splz nesting */ 234 #ifdef SMP 235 int td_mpcount; /* MP lock held (count) */ 236 int td_cscount; /* cpu synchronization master */ 237 #else 238 int td_unused001; 239 int td_unused002; 240 #endif 241 struct timeval td_start; /* start time for a thread/process */ 242 char td_comm[MAXCOMLEN+1]; /* typ 16+1 bytes */ 243 struct thread *td_preempted; /* we preempted this thread */ 244 struct caps_kinfo *td_caps; /* list of client and server registrations */ 245 lwkt_tokref_t td_toks; /* tokens beneficially held */ 246 struct md_thread td_mach; 247 }; 248 249 /* 250 * Thread flags. Note that TDF_RUNNING is cleared on the old thread after 251 * we switch to the new one, which is necessary because LWKTs don't need 252 * to hold the BGL. This flag is used by the exit code and the managed 253 * thread migration code. 254 * 255 * LWKT threads stay on their (per-cpu) run queue while running, not to 256 * be confused with user processes which are removed from the user scheduling 257 * run queue while actually running. 258 */ 259 #define TDF_RUNNING 0x0001 /* thread still active */ 260 #define TDF_RUNQ 0x0002 /* on an LWKT run queue */ 261 #define TDF_PREEMPT_LOCK 0x0004 /* I have been preempted */ 262 #define TDF_PREEMPT_DONE 0x0008 /* acknowledge preemption complete */ 263 #define TDF_IDLE_NOHLT 0x0010 /* we need to spin */ 264 #define TDF_MIGRATING 0x0020 /* thread is being migrated */ 265 #define TDF_SINTR 0x0040 /* interruptability hint for 'ps' */ 266 267 #define TDF_SYSTHREAD 0x0100 /* system thread */ 268 #define TDF_ALLOCATED_THREAD 0x0200 /* zalloc allocated thread */ 269 #define TDF_ALLOCATED_STACK 0x0400 /* zalloc allocated stack */ 270 #define TDF_VERBOSE 0x0800 /* verbose on exit */ 271 #define TDF_DEADLKTREAT 0x1000 /* special lockmgr deadlock treatment */ 272 #define TDF_STOPREQ 0x2000 /* suspend_kproc */ 273 #define TDF_WAKEREQ 0x4000 /* resume_kproc */ 274 #define TDF_TIMEOUT 0x8000 /* tsleep timeout */ 275 #define TDF_INTTHREAD 0x00010000 /* interrupt thread */ 276 #define TDF_NORESCHED 0x00020000 /* Do not reschedule on wake */ 277 #define TDF_BLOCKED 0x00040000 /* Thread is blocked */ 278 279 /* 280 * Thread priorities. Typically only one thread from any given 281 * user process scheduling queue is on the LWKT run queue at a time. 282 * Remember that there is one LWKT run queue per cpu. 283 * 284 * Critical sections are handled by bumping td_pri above TDPRI_MAX, which 285 * causes interrupts to be masked as they occur. When this occurs a 286 * rollup flag will be set in mycpu->gd_reqflags. 287 */ 288 #define TDPRI_IDLE_THREAD 0 /* the idle thread */ 289 #define TDPRI_USER_IDLE 4 /* user scheduler idle */ 290 #define TDPRI_USER_NORM 6 /* user scheduler normal */ 291 #define TDPRI_USER_REAL 8 /* user scheduler real time */ 292 #define TDPRI_KERN_LPSCHED 9 /* scheduler helper for userland sch */ 293 #define TDPRI_KERN_USER 10 /* kernel / block in syscall */ 294 #define TDPRI_KERN_DAEMON 12 /* kernel daemon (pageout, etc) */ 295 #define TDPRI_SOFT_NORM 14 /* kernel / normal */ 296 #define TDPRI_SOFT_TIMER 16 /* kernel / timer */ 297 #define TDPRI_EXITING 19 /* exiting thread */ 298 #define TDPRI_INT_SUPPORT 20 /* kernel / high priority support */ 299 #define TDPRI_INT_LOW 27 /* low priority interrupt */ 300 #define TDPRI_INT_MED 28 /* medium priority interrupt */ 301 #define TDPRI_INT_HIGH 29 /* high priority interrupt */ 302 #define TDPRI_MAX 31 303 304 #define TDPRI_MASK 31 305 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */ 306 307 #define LWKT_THREAD_STACK (UPAGES * PAGE_SIZE) 308 309 #define CACHE_NTHREADS 6 310 311 #define IN_CRITICAL_SECT(td) ((td)->td_pri >= TDPRI_CRIT) 312 313 #ifdef _KERNEL 314 315 extern struct vm_zone *thread_zone; 316 317 #endif 318 319 /* 320 * Applies both to the kernel and to liblwkt. 321 */ 322 extern struct thread *lwkt_alloc_thread(struct thread *template, int stksize, 323 int cpu); 324 extern void lwkt_init_thread(struct thread *td, void *stack, int stksize, 325 int flags, struct globaldata *gd); 326 extern void lwkt_set_comm(thread_t td, const char *ctl, ...); 327 extern void lwkt_wait_free(struct thread *td); 328 extern void lwkt_free_thread(struct thread *td); 329 extern void lwkt_wait_init(struct lwkt_wait *w); 330 extern void lwkt_gdinit(struct globaldata *gd); 331 extern void lwkt_switch(void); 332 extern void lwkt_preempt(thread_t ntd, int critpri); 333 extern void lwkt_schedule(thread_t td); 334 extern void lwkt_schedule_self(thread_t td); 335 extern void lwkt_deschedule(thread_t td); 336 extern void lwkt_deschedule_self(thread_t td); 337 extern void lwkt_acquire(thread_t td); 338 extern void lwkt_yield(void); 339 extern void lwkt_yield_quick(void); 340 extern void lwkt_token_wait(void); 341 extern void lwkt_hold(thread_t td); 342 extern void lwkt_rele(thread_t td); 343 344 extern void lwkt_block(lwkt_wait_t w, const char *wmesg, int *gen); 345 extern void lwkt_signal(lwkt_wait_t w, int count); 346 347 extern int lwkt_havetoken(lwkt_token_t tok); 348 extern int lwkt_havetokref(lwkt_tokref_t xref); 349 extern void lwkt_gettoken(lwkt_tokref_t ref, lwkt_token_t tok); 350 extern int lwkt_trytoken(lwkt_tokref_t ref, lwkt_token_t tok); 351 extern void lwkt_gettokref(lwkt_tokref_t ref); 352 extern int lwkt_trytokref(lwkt_tokref_t ref); 353 extern void lwkt_reltoken(lwkt_tokref_t ref); 354 extern void lwkt_reqtoken_remote(void *data); 355 extern int lwkt_chktokens(thread_t td); 356 extern void lwkt_drain_token_requests(void); 357 extern void lwkt_token_init(lwkt_token_t tok); 358 extern void lwkt_token_uninit(lwkt_token_t tok); 359 360 extern void lwkt_token_pool_init(void); 361 extern lwkt_token_t lwkt_token_pool_get(void *ptraddr); 362 363 extern void lwkt_rwlock_init(lwkt_rwlock_t lock); 364 extern void lwkt_rwlock_uninit(lwkt_rwlock_t lock); 365 extern void lwkt_exlock(lwkt_rwlock_t lock, const char *wmesg); 366 extern void lwkt_shlock(lwkt_rwlock_t lock, const char *wmesg); 367 extern void lwkt_exunlock(lwkt_rwlock_t lock); 368 extern void lwkt_shunlock(lwkt_rwlock_t lock); 369 370 extern void lwkt_setpri(thread_t td, int pri); 371 extern void lwkt_setpri_self(int pri); 372 extern int lwkt_checkpri_self(void); 373 extern void lwkt_setcpu_self(struct globaldata *rgd); 374 extern int lwkt_send_ipiq(struct globaldata *targ, ipifunc_t func, void *arg); 375 extern int lwkt_send_ipiq_passive(struct globaldata *targ, ipifunc_t func, void *arg); 376 extern int lwkt_send_ipiq_bycpu(int dcpu, ipifunc_t func, void *arg); 377 extern int lwkt_send_ipiq_mask(cpumask_t mask, ipifunc_t func, void *arg); 378 extern void lwkt_wait_ipiq(struct globaldata *targ, int seq); 379 extern int lwkt_seq_ipiq(struct globaldata *targ); 380 extern void lwkt_process_ipiq(void); 381 #ifdef _KERNEL 382 extern void lwkt_process_ipiq_frame(struct intrframe frame); 383 #endif 384 extern void lwkt_cpusync_simple(cpumask_t mask, cpusync_func_t func, void *data); 385 extern void lwkt_cpusync_fastdata(cpumask_t mask, cpusync_func2_t func, void *data); 386 extern void lwkt_cpusync_start(cpumask_t mask, lwkt_cpusync_t poll); 387 extern void lwkt_cpusync_add(cpumask_t mask, lwkt_cpusync_t poll); 388 extern void lwkt_cpusync_finish(lwkt_cpusync_t poll); 389 extern void crit_panic(void); 390 extern struct proc *lwkt_preempted_proc(void); 391 392 extern int lwkt_create (void (*func)(void *), void *arg, struct thread **ptd, 393 struct thread *template, int tdflags, int cpu, 394 const char *ctl, ...); 395 extern void lwkt_exit (void) __dead2; 396 397 #endif 398 399