include/linux/sched.h

/* */
This source file includes following definitions.
add_wait_queue
remove_wait_queue
select_wait
down
up
   1 #ifndef _LINUX_SCHED_H
   2 #define _LINUX_SCHED_H
   3 
   4 /*
   5  * define DEBUG if you want the wait-queues to have some extra
   6  * debugging code. It's not normally used, but might catch some
   7  * wait-queue coding errors.
   8  *
   9  *  #define DEBUG
  10  */
  11 
  12 #include <asm/param.h>  /* for HZ */
  13 
  14 extern unsigned long intr_count;
  15 extern unsigned long event;
  16 
  17 #include <linux/binfmts.h>
  18 #include <linux/personality.h>
  19 #include <linux/tasks.h>
  20 #include <linux/kernel.h>
  21 #include <asm/system.h>
  22 #include <asm/page.h>
  23 
  24 #include <linux/smp.h>
  25 
  26 /*
  27  * cloning flags:
  28  */
  29 #define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
  30 #define CLONE_VM        0x00000100      /* set if VM shared between processes */
  31 #define CLONE_FS        0x00000200      /* set if fs info shared between processes */
  32 #define CLONE_FILES     0x00000400      /* set if open files shared between processes */
  33 #define CLONE_SIGHAND   0x00000800      /* set if signal handlers shared */
  34 #define CLONE_PID       0x00001000      /* set if pid shared */
  35 
  36 /*
  37  * These are the constant used to fake the fixed-point load-average
  38  * counting. Some notes:
  39  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
  40  *    a load-average precision of 10 bits integer + 11 bits fractional
  41  *  - if you want to count load-averages more often, you need more
  42  *    precision, or rounding will get you. With 2-second counting freq,
  43  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
  44  *    11 bit fractions.
  45  */
  46 extern unsigned long avenrun[];         /* Load averages */
  47 
  48 #define FSHIFT          11              /* nr of bits of precision */
  49 #define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
  50 #define LOAD_FREQ       (5*HZ)          /* 5 sec intervals */
  51 #define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
  52 #define EXP_5           2014            /* 1/exp(5sec/5min) */
  53 #define EXP_15          2037            /* 1/exp(5sec/15min) */
  54 
  55 #define CALC_LOAD(load,exp,n) \
  56         load *= exp; \
  57         load += n*(FIXED_1-exp); \
  58         load >>= FSHIFT;
  59 
  60 #define CT_TO_SECS(x)   ((x) / HZ)
  61 #define CT_TO_USECS(x)  (((x) % HZ) * 1000000/HZ)
  62 
  63 extern int nr_running, nr_tasks;
  64 
  65 #define FIRST_TASK task[0]
  66 #define LAST_TASK task[NR_TASKS-1]
  67 
  68 #include <linux/head.h>
  69 #include <linux/fs.h>
  70 #include <linux/signal.h>
  71 #include <linux/time.h>
  72 #include <linux/param.h>
  73 #include <linux/resource.h>
  74 #include <linux/vm86.h>
  75 #include <linux/math_emu.h>
  76 #include <linux/ptrace.h>
  77 #include <linux/timer.h>
  78 
  79 #include <asm/processor.h>
  80 
  81 #define TASK_RUNNING            0
  82 #define TASK_INTERRUPTIBLE      1
  83 #define TASK_UNINTERRUPTIBLE    2
  84 #define TASK_ZOMBIE             3
  85 #define TASK_STOPPED            4
  86 #define TASK_SWAPPING           5
  87 
  88 /*
  89  * Scheduling policies
  90  */
  91 #define SCHED_OTHER             0
  92 #define SCHED_FIFO              1
  93 #define SCHED_RR                2
  94 
  95 #ifndef NULL
  96 #define NULL ((void *) 0)
  97 #endif
  98 
  99 #ifdef __KERNEL__
 100 
 101 #define barrier() __asm__("": : :"memory")
 102 
 103 extern void sched_init(void);
 104 extern void show_state(void);
 105 extern void trap_init(void);
 106 
 107 asmlinkage void schedule(void);
 108 
 109 struct files_struct {
 110         int count;
 111         fd_set close_on_exec;
 112         struct file * fd[NR_OPEN];
 113 };
 114 
 115 #define INIT_FILES { \
 116         1, \
 117         { { 0, } }, \
 118         { NULL, } \
 119 }
 120 
 121 struct fs_struct {
 122         int count;
 123         unsigned short umask;
 124         struct inode * root, * pwd;
 125 };
 126 
 127 #define INIT_FS { \
 128         1, \
 129         0022, \
 130         NULL, NULL \
 131 }
 132 
 133 struct mm_struct {
 134         int count;
 135         pgd_t * pgd;
 136         unsigned long context;
 137         unsigned long start_code, end_code, start_data, end_data;
 138         unsigned long start_brk, brk, start_stack, start_mmap;
 139         unsigned long arg_start, arg_end, env_start, env_end;
 140         unsigned long rss, total_vm, locked_vm;
 141         unsigned long def_flags;
 142         struct vm_area_struct * mmap;
 143         struct vm_area_struct * mmap_avl;
 144 };
 145 
 146 #define INIT_MM { \
 147                 1, \
 148                 swapper_pg_dir, \
 149                 0, \
 150                 0, 0, 0, 0, \
 151                 0, 0, 0, 0, \
 152                 0, 0, 0, 0, \
 153                 0, 0, 0, \
 154                 0, \
 155                 &init_mmap, &init_mmap }
 156 
 157 struct signal_struct {
 158         int count;
 159         struct sigaction action[32];
 160 };
 161 
 162 #define INIT_SIGNALS { \
 163                 1, \
 164                 { {0,}, } }
 165 
 166 struct task_struct {
 167 /* these are hardcoded - don't touch */
 168         volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
 169         long counter;
 170         long priority;
 171         unsigned long signal;
 172         unsigned long blocked;  /* bitmap of masked signals */
 173         unsigned long flags;    /* per process flags, defined below */
 174         int errno;
 175         long debugreg[8];  /* Hardware debugging registers */
 176         struct exec_domain *exec_domain;
 177 /* various fields */
 178         struct linux_binfmt *binfmt;
 179         struct task_struct *next_task, *prev_task;
 180         struct task_struct *next_run,  *prev_run;
 181         unsigned long saved_kernel_stack;
 182         unsigned long kernel_stack_page;
 183         int exit_code, exit_signal;
 184         unsigned long personality;
 185         int dumpable:1;
 186         int did_exec:1;
 187         int pid,pgrp,tty_old_pgrp,session,leader;
 188         int     groups[NGROUPS];
 189         /* 
 190          * pointers to (original) parent process, youngest child, younger sibling,
 191          * older sibling, respectively.  (p->father can be replaced with 
 192          * p->p_pptr->pid)
 193          */
 194         struct task_struct *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
 195         struct wait_queue *wait_chldexit;       /* for wait4() */
 196         unsigned short uid,euid,suid,fsuid;
 197         unsigned short gid,egid,sgid,fsgid;
 198         unsigned long timeout, policy;
 199         unsigned long it_real_value, it_prof_value, it_virt_value;
 200         unsigned long it_real_incr, it_prof_incr, it_virt_incr;
 201         struct timer_list real_timer;
 202         long utime, stime, cutime, cstime, start_time;
 203 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
 204         unsigned long min_flt, maj_flt, nswap, cmin_flt, cmaj_flt, cnswap;
 205         int swappable:1;
 206         unsigned long swap_address;
 207         unsigned long old_maj_flt;      /* old value of maj_flt */
 208         unsigned long dec_flt;          /* page fault count of the last time */
 209         unsigned long swap_cnt;         /* number of pages to swap on next pass */
 210 /* limits */
 211         struct rlimit rlim[RLIM_NLIMITS];
 212         unsigned short used_math;
 213         char comm[16];
 214 /* file system info */
 215         int link_count;
 216         struct tty_struct *tty; /* NULL if no tty */
 217 /* ipc stuff */
 218         struct sem_undo *semundo;
 219         struct sem_queue *semsleeping;
 220 /* ldt for this task - used by Wine.  If NULL, default_ldt is used */
 221         struct desc_struct *ldt;
 222 /* tss for this task */
 223         struct thread_struct tss;
 224 /* filesystem information */
 225         struct fs_struct *fs;
 226 /* open file information */
 227         struct files_struct *files;
 228 /* memory management info */
 229         struct mm_struct *mm;
 230 /* signal handlers */
 231         struct signal_struct *sig;
 232 #ifdef __SMP__
 233         int processor;
 234         int last_processor;
 235         int lock_depth;         /* Lock depth. We can context switch in and out of holding a syscall kernel lock... */  
 236 #endif  
 237 };
 238 
 239 /*
 240  * Per process flags
 241  */
 242 #define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
 243                                         /* Not implemented yet, only for 486*/
 244 #define PF_PTRACED      0x00000010      /* set if ptrace (0) has been called. */
 245 #define PF_TRACESYS     0x00000020      /* tracing system calls */
 246 
 247 #define PF_STARTING     0x00000100      /* being created */
 248 #define PF_EXITING      0x00000200      /* getting shut down */
 249 
 250 #define PF_USEDFPU      0x00100000      /* Process used the FPU this quantum (SMP only) */
 251 
 252 /*
 253  * Limit the stack by to some sane default: root can always
 254  * increase this limit if needed..  8MB seems reasonable.
 255  */
 256 #define _STK_LIM        (8*1024*1024)
 257 
 258 #define DEF_PRIORITY    (20*HZ/100)     /* 200 ms time slices */
 259 
 260 /*
 261  *  INIT_TASK is used to set up the first task table, touch at
 262  * your own risk!. Base=0, limit=0x1fffff (=2MB)
 263  */
 264 #define INIT_TASK \
 265 /* state etc */ { 0,DEF_PRIORITY,DEF_PRIORITY,0,0,0,0, \
 266 /* debugregs */ { 0, },            \
 267 /* exec domain */&default_exec_domain, \
 268 /* binfmt */    NULL, \
 269 /* schedlink */ &init_task,&init_task, &init_task, &init_task, \
 270 /* stack */     0,(unsigned long) &init_kernel_stack, \
 271 /* ec,brk... */ 0,0,0,0,0, \
 272 /* pid etc.. */ 0,0,0,0,0, \
 273 /* suppl grps*/ {NOGROUP,}, \
 274 /* proc links*/ &init_task,&init_task,NULL,NULL,NULL,NULL, \
 275 /* uid etc */   0,0,0,0,0,0,0,0, \
 276 /* timeout */   0,SCHED_OTHER,0,0,0,0,0,0, \
 277 /* timer */     { NULL, NULL, 0, 0, it_real_fn }, \
 278 /* utime */     0,0,0,0,0, \
 279 /* flt */       0,0,0,0,0,0, \
 280 /* swp */       0,0,0,0,0, \
 281 /* rlimits */   INIT_RLIMITS, \
 282 /* math */      0, \
 283 /* comm */      "swapper", \
 284 /* fs info */   0,NULL, \
 285 /* ipc */       NULL, NULL, \
 286 /* ldt */       NULL, \
 287 /* tss */       INIT_TSS, \
 288 /* fs */        &init_fs, \
 289 /* files */     &init_files, \
 290 /* mm */        &init_mm, \
 291 /* signals */   &init_signals, \
 292 }
 293 
 294 extern struct   mm_struct init_mm;
 295 extern struct task_struct init_task;
 296 extern struct task_struct *task[NR_TASKS];
 297 extern struct task_struct *last_task_used_math;
 298 extern struct task_struct *current_set[NR_CPUS];
 299 /*
 300  *      On a single processor system this comes out as current_set[0] when cpp
 301  *      has finished with it, which gcc will optimise away.
 302  */
 303 #define current (0+current_set[smp_processor_id()])     /* Current on this processor */
 304 extern unsigned long volatile jiffies;
 305 extern unsigned long itimer_ticks;
 306 extern unsigned long itimer_next;
 307 extern struct timeval xtime;
 308 extern int need_resched;
 309 extern void do_timer(struct pt_regs *);
 310 
 311 extern unsigned long * prof_buffer;
 312 extern unsigned long prof_len;
 313 extern unsigned long prof_shift;
 314 
 315 #define CURRENT_TIME (xtime.tv_sec)
 316 
 317 extern void sleep_on(struct wait_queue ** p);
 318 extern void interruptible_sleep_on(struct wait_queue ** p);
 319 extern void wake_up(struct wait_queue ** p);
 320 extern void wake_up_interruptible(struct wait_queue ** p);
 321 extern void wake_up_process(struct task_struct * tsk);
 322 
 323 extern void notify_parent(struct task_struct * tsk);
 324 extern int send_sig(unsigned long sig,struct task_struct * p,int priv);
 325 extern int in_group_p(gid_t grp);
 326 
 327 extern int request_irq(unsigned int irq,void (*handler)(int, struct pt_regs *),
 328         unsigned long flags, const char *device);
 329 extern void free_irq(unsigned int irq);
 330 
 331 extern void copy_thread(int, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
 332 extern void flush_thread(void);
 333 extern void exit_thread(void);
 334 
 335 extern void exit_fs(struct task_struct *);
 336 extern void exit_files(struct task_struct *);
 337 extern void exit_sighand(struct task_struct *);
 338 extern void release_thread(struct task_struct *);
 339 
 340 extern int do_execve(char *, char **, char **, struct pt_regs *);
 341 extern int do_fork(unsigned long, unsigned long, struct pt_regs *);
 342 
 343 /*
 344  * The wait-queues are circular lists, and you have to be *very* sure
 345  * to keep them correct. Use only these two functions to add/remove
 346  * entries in the queues.
 347  */
 348 extern inline void add_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 349 {
 350         unsigned long flags;
 351 
 352 #ifdef DEBUG
 353         if (wait->next) {
 354                 __label__ here;
 355                 unsigned long pc;
 356                 pc = (unsigned long) &&here;
 357               here:
 358                 printk("add_wait_queue (%08lx): wait->next = %08lx\n",pc,(unsigned long) wait->next);
 359         }
 360 #endif
 361         save_flags(flags);
 362         cli();
 363         if (!*p) {
 364                 wait->next = wait;
 365                 *p = wait;
 366         } else {
 367                 wait->next = (*p)->next;
 368                 (*p)->next = wait;
 369         }
 370         restore_flags(flags);
 371 }
 372 
 373 extern inline void remove_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 374 {
 375         unsigned long flags;
 376         struct wait_queue * tmp;
 377 #ifdef DEBUG
 378         unsigned long ok = 0;
 379 #endif
 380 
 381         save_flags(flags);
 382         cli();
 383         if ((*p == wait) &&
 384 #ifdef DEBUG
 385             (ok = 1) &&
 386 #endif
 387             ((*p = wait->next) == wait)) {
 388                 *p = NULL;
 389         } else {
 390                 tmp = wait;
 391                 while (tmp->next != wait) {
 392                         tmp = tmp->next;
 393 #ifdef DEBUG
 394                         if (tmp == *p)
 395                                 ok = 1;
 396 #endif
 397                 }
 398                 tmp->next = wait->next;
 399         }
 400         wait->next = NULL;
 401         restore_flags(flags);
 402 #ifdef DEBUG
 403         if (!ok) {
 404                 __label__ here;
 405                 ok = (unsigned long) &&here;
 406                 printk("removed wait_queue not on list.\n");
 407                 printk("list = %08lx, queue = %08lx\n",(unsigned long) p, (unsigned long) wait);
 408               here:
 409                 printk("eip = %08lx\n",ok);
 410         }
 411 #endif
 412 }
 413 
 414 extern inline void select_wait(struct wait_queue ** wait_address, select_table * p)
     /*  */
 415 {
 416         struct select_table_entry * entry;
 417 
 418         if (!p || !wait_address)
 419                 return;
 420         if (p->nr >= __MAX_SELECT_TABLE_ENTRIES)
 421                 return;
 422         entry = p->entry + p->nr;
 423         entry->wait_address = wait_address;
 424         entry->wait.task = current;
 425         entry->wait.next = NULL;
 426         add_wait_queue(wait_address,&entry->wait);
 427         p->nr++;
 428 }
 429 
 430 extern void __down(struct semaphore * sem);
 431 
 432 /*
 433  * These are not yet interrupt-safe
 434  */
 435 extern inline void down(struct semaphore * sem)
     /*  */
 436 {
 437         if (sem->count <= 0)
 438                 __down(sem);
 439         sem->count--;
 440 }
 441 
 442 extern inline void up(struct semaphore * sem)
     /*  */
 443 {
 444         sem->count++;
 445         wake_up(&sem->wait);
 446 }       
 447 
 448 #define REMOVE_LINKS(p) do { unsigned long flags; \
 449         save_flags(flags) ; cli(); \
 450         (p)->next_task->prev_task = (p)->prev_task; \
 451         (p)->prev_task->next_task = (p)->next_task; \
 452         restore_flags(flags); \
 453         if ((p)->p_osptr) \
 454                 (p)->p_osptr->p_ysptr = (p)->p_ysptr; \
 455         if ((p)->p_ysptr) \
 456                 (p)->p_ysptr->p_osptr = (p)->p_osptr; \
 457         else \
 458                 (p)->p_pptr->p_cptr = (p)->p_osptr; \
 459         } while (0)
 460 
 461 #define SET_LINKS(p) do { unsigned long flags; \
 462         save_flags(flags); cli(); \
 463         (p)->next_task = &init_task; \
 464         (p)->prev_task = init_task.prev_task; \
 465         init_task.prev_task->next_task = (p); \
 466         init_task.prev_task = (p); \
 467         restore_flags(flags); \
 468         (p)->p_ysptr = NULL; \
 469         if (((p)->p_osptr = (p)->p_pptr->p_cptr) != NULL) \
 470                 (p)->p_osptr->p_ysptr = p; \
 471         (p)->p_pptr->p_cptr = p; \
 472         } while (0)
 473 
 474 #define for_each_task(p) \
 475         for (p = &init_task ; (p = p->next_task) != &init_task ; )
 476 
 477 #endif /* __KERNEL__ */
 478 
 479 #endif
/* */
root/include/linux/sched.h

INCLUDED FROM

DEFINITIONS
