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 1.86 2006/06/04 21:09:50 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 #ifndef _SYS_SPINLOCK_H_ 32 #include <sys/spinlock.h> 33 #endif 34 #ifndef _MACHINE_THREAD_H_ 35 #include <machine/thread.h> 36 #endif 37 38 struct globaldata; 39 struct lwp; 40 struct proc; 41 struct thread; 42 struct lwkt_queue; 43 struct lwkt_token; 44 struct lwkt_tokref; 45 struct lwkt_ipiq; 46 struct lwkt_cpu_msg; 47 struct lwkt_cpu_port; 48 struct lwkt_msg; 49 struct lwkt_port; 50 struct lwkt_cpusync; 51 union sysunion; 52 53 typedef struct lwkt_queue *lwkt_queue_t; 54 typedef struct lwkt_token *lwkt_token_t; 55 typedef struct lwkt_tokref *lwkt_tokref_t; 56 typedef struct lwkt_cpu_msg *lwkt_cpu_msg_t; 57 typedef struct lwkt_cpu_port *lwkt_cpu_port_t; 58 typedef struct lwkt_ipiq *lwkt_ipiq_t; 59 typedef struct lwkt_cpusync *lwkt_cpusync_t; 60 typedef struct thread *thread_t; 61 62 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue; 63 64 /* 65 * Differentiation between kernel threads and user threads. Userland 66 * programs which want to access to kernel structures have to define 67 * _KERNEL_STRUCTURES. This is a kinda safety valve to prevent badly 68 * written user programs from getting an LWKT thread that is neither the 69 * kernel nor the user version. 70 */ 71 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) 72 #ifndef _MACHINE_THREAD_H_ 73 #include <machine/thread.h> /* md_thread */ 74 #endif 75 #ifndef _MACHINE_FRAME_H_ 76 #include <machine/frame.h> 77 #endif 78 #else 79 struct intrframe; 80 #endif 81 82 /* 83 * Tokens are used to serialize access to information. They are 'soft' 84 * serialization entities that only stay in effect while a thread is 85 * running. If the thread blocks, other threads can run holding the same 86 * token(s). The tokens are reacquired when the original thread resumes. 87 * 88 * A thread can depend on its serialization remaining intact through a 89 * preemption. An interrupt which attempts to use the same token as the 90 * thread being preempted will reschedule itself for non-preemptive 91 * operation, so the new token code is capable of interlocking against 92 * interrupts as well as other cpus. 93 * 94 * Tokens are managed through a helper reference structure, lwkt_tokref, 95 * which is typically declared on the caller's stack. Multiple tokref's 96 * may reference the same token. 97 * 98 * We do not actually have to track any information in the token itself 99 * on UP systems. Simply linking the reference into the thread's td_toks 100 * list is sufficient. We still track a global t_globalcount on UP for 101 * debugging purposes. 102 */ 103 #ifdef SMP 104 105 typedef struct lwkt_token { 106 struct spinlock t_spinlock; /* Controls access */ 107 struct thread *t_owner; /* The current owner of the token */ 108 int t_count; /* Per-thread count */ 109 } lwkt_token; 110 111 #else 112 113 typedef struct lwkt_token { 114 struct spinlock t_unused01; 115 struct thread *t_unused02; 116 int t_globalcount; /* Global reference count */ 117 } lwkt_token; 118 119 #endif 120 121 typedef struct lwkt_tokref { 122 lwkt_token_t tr_tok; /* token in question */ 123 lwkt_tokref_t tr_next; /* linked list */ 124 int tr_state; /* 0 = don't have, 1 = have */ 125 } lwkt_tokref; 126 127 #define LWKT_TOKREF_INIT(tok) \ 128 { tok, NULL, 0 } 129 #define LWKT_TOKREF_DECLARE(name, tok) \ 130 lwkt_tokref name = LWKT_TOKREF_INIT(tok) 131 132 #define MAXCPUFIFO 16 /* power of 2 */ 133 #define MAXCPUFIFO_MASK (MAXCPUFIFO - 1) 134 #define LWKT_MAXTOKENS 16 /* max tokens beneficially held by thread */ 135 136 /* 137 * Always cast to ipifunc_t when registering an ipi. The actual ipi function 138 * is called with both the data and an interrupt frame, but the ipi function 139 * that is registered might only declare a data argument. 140 */ 141 typedef void (*ipifunc1_t)(void *arg); 142 typedef void (*ipifunc2_t)(void *arg, int arg2); 143 typedef void (*ipifunc3_t)(void *arg, int arg2, struct intrframe *frame); 144 145 typedef struct lwkt_ipiq { 146 int ip_rindex; /* only written by target cpu */ 147 int ip_xindex; /* written by target, indicates completion */ 148 int ip_windex; /* only written by source cpu */ 149 ipifunc3_t ip_func[MAXCPUFIFO]; 150 void *ip_arg1[MAXCPUFIFO]; 151 int ip_arg2[MAXCPUFIFO]; 152 u_int ip_npoll; /* synchronization to avoid excess IPIs */ 153 } lwkt_ipiq; 154 155 /* 156 * CPU Synchronization structure. See lwkt_cpusync_start() and 157 * lwkt_cpusync_finish() for more information. 158 */ 159 typedef void (*cpusync_func_t)(lwkt_cpusync_t poll); 160 typedef void (*cpusync_func2_t)(void *data); 161 162 struct lwkt_cpusync { 163 cpusync_func_t cs_run_func; /* run (tandem w/ acquire) */ 164 cpusync_func_t cs_fin1_func; /* fin1 (synchronized) */ 165 cpusync_func2_t cs_fin2_func; /* fin2 (tandem w/ release) */ 166 void *cs_data; 167 int cs_maxcount; 168 volatile int cs_count; 169 cpumask_t cs_mask; 170 }; 171 172 /* 173 * The standard message and queue structure used for communications between 174 * cpus. Messages are typically queued via a machine-specific non-linked 175 * FIFO matrix allowing any cpu to send a message to any other cpu without 176 * blocking. 177 */ 178 typedef struct lwkt_cpu_msg { 179 void (*cm_func)(lwkt_cpu_msg_t msg); /* primary dispatch function */ 180 int cm_code; /* request code if applicable */ 181 int cm_cpu; /* reply to cpu */ 182 thread_t cm_originator; /* originating thread for wakeup */ 183 } lwkt_cpu_msg; 184 185 /* 186 * Thread structure. Note that ownership of a thread structure is special 187 * cased and there is no 'token'. A thread is always owned by the cpu 188 * represented by td_gd, any manipulation of the thread by some other cpu 189 * must be done through cpu_*msg() functions. e.g. you could request 190 * ownership of a thread that way, or hand a thread off to another cpu. 191 * 192 * NOTE: td_pri is bumped by TDPRI_CRIT when entering a critical section, 193 * but this does not effect how the thread is scheduled by LWKT. 194 */ 195 struct md_intr_info; 196 struct caps_kinfo; 197 198 struct thread { 199 TAILQ_ENTRY(thread) td_threadq; 200 TAILQ_ENTRY(thread) td_allq; 201 lwkt_port td_msgport; /* built-in message port for replies */ 202 struct lwp *td_lwp; /* (optional) associated lwp */ 203 struct proc *td_proc; /* (optional) associated process */ 204 struct pcb *td_pcb; /* points to pcb and top of kstack */ 205 struct globaldata *td_gd; /* associated with this cpu */ 206 const char *td_wmesg; /* string name for blockage */ 207 void *td_wchan; /* waiting on channel */ 208 int td_pri; /* 0-31, 31=highest priority (note 1) */ 209 int td_flags; /* TDF flags */ 210 int td_wdomain; /* domain for wchan address (typ 0) */ 211 void (*td_preemptable)(struct thread *td, int critpri); 212 void (*td_release)(struct thread *td); 213 char *td_kstack; /* kernel stack */ 214 int td_kstack_size; /* size of kernel stack */ 215 char *td_sp; /* kernel stack pointer for LWKT restore */ 216 void (*td_switch)(struct thread *ntd); 217 __uint64_t td_uticks; /* Statclock hits in user mode (uS) */ 218 __uint64_t td_sticks; /* Statclock hits in system mode (uS) */ 219 __uint64_t td_iticks; /* Statclock hits processing intr (uS) */ 220 int td_locks; /* lockmgr lock debugging */ 221 int td_unused01; 222 int td_refs; /* hold position in gd_tdallq / hold free */ 223 int td_nest_count; /* prevent splz nesting */ 224 #ifdef SMP 225 int td_mpcount; /* MP lock held (count) */ 226 int td_cscount; /* cpu synchronization master */ 227 #else 228 int td_mpcount_unused; /* filler so size matches */ 229 int td_cscount_unused; 230 #endif 231 struct timeval td_start; /* start time for a thread/process */ 232 char td_comm[MAXCOMLEN+1]; /* typ 16+1 bytes */ 233 struct thread *td_preempted; /* we preempted this thread */ 234 struct caps_kinfo *td_caps; /* list of client and server registrations */ 235 lwkt_tokref_t td_toks; /* tokens beneficially held */ 236 #ifdef DEBUG_CRIT_SECTIONS 237 #define CRIT_DEBUG_ARRAY_SIZE 32 238 #define CRIT_DEBUG_ARRAY_MASK (CRIT_DEBUG_ARRAY_SIZE - 1) 239 const char *td_crit_debug_array[CRIT_DEBUG_ARRAY_SIZE]; 240 int td_crit_debug_index; 241 int td_in_crit_report; 242 #endif 243 struct md_thread td_mach; 244 }; 245 246 /* 247 * Thread flags. Note that TDF_RUNNING is cleared on the old thread after 248 * we switch to the new one, which is necessary because LWKTs don't need 249 * to hold the BGL. This flag is used by the exit code and the managed 250 * thread migration code. Note in addition that preemption will cause 251 * TDF_RUNNING to be cleared temporarily, so any code checking TDF_RUNNING 252 * must also check TDF_PREEMPT_LOCK. 253 * 254 * LWKT threads stay on their (per-cpu) run queue while running, not to 255 * be confused with user processes which are removed from the user scheduling 256 * run queue while actually running. 257 * 258 * td_threadq can represent the thread on one of three queues... the LWKT 259 * run queue, a tsleep queue, or an lwkt blocking queue. The LWKT subsystem 260 * does not allow a thread to be scheduled if it already resides on some 261 * queue. 262 */ 263 #define TDF_RUNNING 0x0001 /* thread still active */ 264 #define TDF_RUNQ 0x0002 /* on an LWKT run queue */ 265 #define TDF_PREEMPT_LOCK 0x0004 /* I have been preempted */ 266 #define TDF_PREEMPT_DONE 0x0008 /* acknowledge preemption complete */ 267 #define TDF_IDLE_NOHLT 0x0010 /* we need to spin */ 268 #define TDF_MIGRATING 0x0020 /* thread is being migrated */ 269 #define TDF_SINTR 0x0040 /* interruptability hint for 'ps' */ 270 #define TDF_TSLEEPQ 0x0080 /* on a tsleep wait queue */ 271 272 #define TDF_SYSTHREAD 0x0100 /* system thread */ 273 #define TDF_ALLOCATED_THREAD 0x0200 /* zalloc allocated thread */ 274 #define TDF_ALLOCATED_STACK 0x0400 /* zalloc allocated stack */ 275 #define TDF_VERBOSE 0x0800 /* verbose on exit */ 276 #define TDF_DEADLKTREAT 0x1000 /* special lockmgr deadlock treatment */ 277 #define TDF_STOPREQ 0x2000 /* suspend_kproc */ 278 #define TDF_WAKEREQ 0x4000 /* resume_kproc */ 279 #define TDF_TIMEOUT 0x8000 /* tsleep timeout */ 280 #define TDF_INTTHREAD 0x00010000 /* interrupt thread */ 281 #define TDF_NORESCHED 0x00020000 /* Do not reschedule on wake */ 282 #define TDF_BLOCKED 0x00040000 /* Thread is blocked */ 283 #define TDF_PANICWARN 0x00080000 /* panic warning in switch */ 284 #define TDF_BLOCKQ 0x00100000 /* on block queue */ 285 #define TDF_MPSAFE 0x00200000 /* (thread creation) */ 286 #define TDF_EXITING 0x00400000 /* thread exiting */ 287 288 /* 289 * Thread priorities. Typically only one thread from any given 290 * user process scheduling queue is on the LWKT run queue at a time. 291 * Remember that there is one LWKT run queue per cpu. 292 * 293 * Critical sections are handled by bumping td_pri above TDPRI_MAX, which 294 * causes interrupts to be masked as they occur. When this occurs a 295 * rollup flag will be set in mycpu->gd_reqflags. 296 */ 297 #define TDPRI_IDLE_THREAD 0 /* the idle thread */ 298 #define TDPRI_USER_SCHEDULER 2 /* user scheduler helper */ 299 #define TDPRI_USER_IDLE 4 /* user scheduler idle */ 300 #define TDPRI_USER_NORM 6 /* user scheduler normal */ 301 #define TDPRI_USER_REAL 8 /* user scheduler real time */ 302 #define TDPRI_KERN_LPSCHED 9 /* scheduler helper for userland sch */ 303 #define TDPRI_KERN_USER 10 /* kernel / block in syscall */ 304 #define TDPRI_KERN_DAEMON 12 /* kernel daemon (pageout, etc) */ 305 #define TDPRI_SOFT_NORM 14 /* kernel / normal */ 306 #define TDPRI_SOFT_TIMER 16 /* kernel / timer */ 307 #define TDPRI_EXITING 19 /* exiting thread */ 308 #define TDPRI_INT_SUPPORT 20 /* kernel / high priority support */ 309 #define TDPRI_INT_LOW 27 /* low priority interrupt */ 310 #define TDPRI_INT_MED 28 /* medium priority interrupt */ 311 #define TDPRI_INT_HIGH 29 /* high priority interrupt */ 312 #define TDPRI_MAX 31 313 314 #define TDPRI_MASK 31 315 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */ 316 317 #ifdef _KERNEL 318 #define LWKT_THREAD_STACK (UPAGES * PAGE_SIZE) 319 #endif 320 321 #define CACHE_NTHREADS 6 322 323 #define IN_CRITICAL_SECT(td) ((td)->td_pri >= TDPRI_CRIT) 324 325 #ifdef _KERNEL 326 327 extern struct vm_zone *thread_zone; 328 329 #endif 330 331 /* 332 * Applies both to the kernel and to liblwkt. 333 */ 334 extern struct thread *lwkt_alloc_thread(struct thread *template, int stksize, 335 int cpu, int flags); 336 extern void lwkt_init_thread(struct thread *td, void *stack, int stksize, 337 int flags, struct globaldata *gd); 338 extern void lwkt_set_comm(thread_t td, const char *ctl, ...); 339 extern void lwkt_wait_free(struct thread *td); 340 extern void lwkt_free_thread(struct thread *td); 341 extern void lwkt_gdinit(struct globaldata *gd); 342 extern void lwkt_switch(void); 343 extern void lwkt_preempt(thread_t ntd, int critpri); 344 extern void lwkt_schedule(thread_t td); 345 extern void lwkt_schedule_self(thread_t td); 346 extern void lwkt_deschedule(thread_t td); 347 extern void lwkt_deschedule_self(thread_t td); 348 extern void lwkt_yield(void); 349 extern void lwkt_yield_quick(void); 350 extern void lwkt_token_wait(void); 351 extern void lwkt_hold(thread_t td); 352 extern void lwkt_rele(thread_t td); 353 354 extern void lwkt_gettoken(lwkt_tokref_t ref, lwkt_token_t tok); 355 extern int lwkt_trytoken(lwkt_tokref_t ref, lwkt_token_t tok); 356 extern void lwkt_gettokref(lwkt_tokref_t ref); 357 extern int lwkt_trytokref(lwkt_tokref_t ref); 358 extern void lwkt_reltoken(lwkt_tokref_t ref); 359 extern int lwkt_getalltokens(thread_t td); 360 extern void lwkt_relalltokens(thread_t td); 361 extern void lwkt_drain_token_requests(void); 362 extern void lwkt_token_init(lwkt_token_t tok); 363 extern void lwkt_token_uninit(lwkt_token_t tok); 364 365 extern void lwkt_token_pool_init(void); 366 extern lwkt_token_t lwkt_token_pool_get(void *ptraddr); 367 368 extern void lwkt_setpri(thread_t td, int pri); 369 extern void lwkt_setpri_self(int pri); 370 extern int lwkt_checkpri_self(void); 371 extern void lwkt_setcpu_self(struct globaldata *rgd); 372 extern void lwkt_migratecpu(int cpuid); 373 374 #ifdef SMP 375 376 extern void lwkt_giveaway(struct thread *); 377 extern void lwkt_acquire(struct thread *); 378 extern int lwkt_send_ipiq3(struct globaldata *targ, ipifunc3_t func, 379 void *arg1, int arg2); 380 extern int lwkt_send_ipiq3_passive(struct globaldata *targ, ipifunc3_t func, 381 void *arg1, int arg2); 382 extern int lwkt_send_ipiq3_nowait(struct globaldata *targ, ipifunc3_t func, 383 void *arg1, int arg2); 384 extern int lwkt_send_ipiq3_bycpu(int dcpu, ipifunc3_t func, 385 void *arg1, int arg2); 386 extern int lwkt_send_ipiq3_mask(cpumask_t mask, ipifunc3_t func, 387 void *arg1, int arg2); 388 extern void lwkt_wait_ipiq(struct globaldata *targ, int seq); 389 extern int lwkt_seq_ipiq(struct globaldata *targ); 390 extern void lwkt_process_ipiq(void); 391 #ifdef _KERNEL 392 extern void lwkt_process_ipiq_frame(struct intrframe frame); 393 #endif 394 extern void lwkt_smp_stopped(void); 395 396 #endif /* SMP */ 397 398 extern void lwkt_cpusync_simple(cpumask_t mask, cpusync_func_t func, void *data); 399 extern void lwkt_cpusync_fastdata(cpumask_t mask, cpusync_func2_t func, void *data); 400 extern void lwkt_cpusync_start(cpumask_t mask, lwkt_cpusync_t poll); 401 extern void lwkt_cpusync_add(cpumask_t mask, lwkt_cpusync_t poll); 402 extern void lwkt_cpusync_finish(lwkt_cpusync_t poll); 403 404 extern void crit_panic(void); 405 extern struct lwp *lwkt_preempted_proc(void); 406 407 extern int lwkt_create (void (*func)(void *), void *arg, struct thread **ptd, 408 struct thread *template, int tdflags, int cpu, 409 const char *ctl, ...); 410 extern void lwkt_exit (void) __dead2; 411 extern void lwkt_remove_tdallq (struct thread *); 412 extern void lwkt_mp_lock_contested(void); 413 414 #endif 415 416