include/linux/sched.h

/* */
This source file includes following definitions.
add_wait_queue
remove_wait_queue
select_wait
down
up
_get_base
get_limit
   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 #define HZ 100
  13 
  14 /*
  15  * System setup and hardware bug flags..
  16  */
  17 extern int hard_math;
  18 extern int x86;
  19 extern char x86_vendor_id[13];
  20 extern fdiv_bug;                
  21 extern int ignore_irq13;
  22 extern int wp_works_ok;         /* doesn't work on a 386 */
  23 extern int hlt_works_ok;        /* problems on some 486Dx4's and old 386's */
  24 
  25 extern unsigned long intr_count;
  26 extern unsigned long event;
  27 
  28 #define start_bh_atomic() \
  29 __asm__ __volatile__("incl _intr_count")
  30 
  31 #define end_bh_atomic() \
  32 __asm__ __volatile__("decl _intr_count")
  33 
  34 /*
  35  * Bus types (default is ISA, but people can check others with these..)
  36  * MCA_bus hardcoded to 0 for now.
  37  */
  38 extern int EISA_bus;
  39 #define MCA_bus 0
  40 
  41 #include <linux/binfmts.h>
  42 #include <linux/personality.h>
  43 #include <linux/tasks.h>
  44 #include <asm/system.h>
  45 
  46 /*
  47  * User space process size: 3GB. This is hardcoded into a few places,
  48  * so don't change it unless you know what you are doing.
  49  */
  50 #define TASK_SIZE       0xc0000000
  51 
  52 /*
  53  * Size of io_bitmap in longwords: 32 is ports 0-0x3ff.
  54  */
  55 #define IO_BITMAP_SIZE  32
  56 
  57 /*
  58  * These are the constant used to fake the fixed-point load-average
  59  * counting. Some notes:
  60  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
  61  *    a load-average precision of 10 bits integer + 11 bits fractional
  62  *  - if you want to count load-averages more often, you need more
  63  *    precision, or rounding will get you. With 2-second counting freq,
  64  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
  65  *    11 bit fractions.
  66  */
  67 extern unsigned long avenrun[];         /* Load averages */
  68 
  69 #define FSHIFT          11              /* nr of bits of precision */
  70 #define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
  71 #define LOAD_FREQ       (5*HZ)          /* 5 sec intervals */
  72 #define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
  73 #define EXP_5           2014            /* 1/exp(5sec/5min) */
  74 #define EXP_15          2037            /* 1/exp(5sec/15min) */
  75 
  76 #define CALC_LOAD(load,exp,n) \
  77         load *= exp; \
  78         load += n*(FIXED_1-exp); \
  79         load >>= FSHIFT;
  80 
  81 #define CT_TO_SECS(x)   ((x) / HZ)
  82 #define CT_TO_USECS(x)  (((x) % HZ) * 1000000/HZ)
  83 
  84 #define FIRST_TASK task[0]
  85 #define LAST_TASK task[NR_TASKS-1]
  86 
  87 #include <linux/head.h>
  88 #include <linux/fs.h>
  89 #include <linux/mm.h>
  90 #include <linux/signal.h>
  91 #include <linux/time.h>
  92 #include <linux/param.h>
  93 #include <linux/resource.h>
  94 #include <linux/vm86.h>
  95 #include <linux/math_emu.h>
  96 #include <linux/ptrace.h>
  97 
  98 #define TASK_RUNNING            0
  99 #define TASK_INTERRUPTIBLE      1
 100 #define TASK_UNINTERRUPTIBLE    2
 101 #define TASK_ZOMBIE             3
 102 #define TASK_STOPPED            4
 103 #define TASK_SWAPPING           5
 104 
 105 #ifndef NULL
 106 #define NULL ((void *) 0)
 107 #endif
 108 
 109 #ifdef __KERNEL__
 110 
 111 extern void sched_init(void);
 112 extern void show_state(void);
 113 extern void trap_init(void);
 114 
 115 asmlinkage void schedule(void);
 116 
 117 #endif /* __KERNEL__ */
 118 
 119 struct i387_hard_struct {
 120         long    cwd;
 121         long    swd;
 122         long    twd;
 123         long    fip;
 124         long    fcs;
 125         long    foo;
 126         long    fos;
 127         long    st_space[20];   /* 8*10 bytes for each FP-reg = 80 bytes */
 128 };
 129 
 130 struct i387_soft_struct {
 131         long    cwd;
 132         long    swd;
 133         long    twd;
 134         long    fip;
 135         long    fcs;
 136         long    foo;
 137         long    fos;
 138         long    top;
 139         struct fpu_reg  regs[8];        /* 8*16 bytes for each FP-reg = 128 bytes */
 140         unsigned char   lookahead;
 141         struct info     *info;
 142         unsigned long   entry_eip;
 143 };
 144 
 145 union i387_union {
 146         struct i387_hard_struct hard;
 147         struct i387_soft_struct soft;
 148 };
 149 
 150 struct tss_struct {
 151         unsigned short  back_link,__blh;
 152         unsigned long   esp0;
 153         unsigned short  ss0,__ss0h;
 154         unsigned long   esp1;
 155         unsigned short  ss1,__ss1h;
 156         unsigned long   esp2;
 157         unsigned short  ss2,__ss2h;
 158         unsigned long   cr3;
 159         unsigned long   eip;
 160         unsigned long   eflags;
 161         unsigned long   eax,ecx,edx,ebx;
 162         unsigned long   esp;
 163         unsigned long   ebp;
 164         unsigned long   esi;
 165         unsigned long   edi;
 166         unsigned short  es, __esh;
 167         unsigned short  cs, __csh;
 168         unsigned short  ss, __ssh;
 169         unsigned short  ds, __dsh;
 170         unsigned short  fs, __fsh;
 171         unsigned short  gs, __gsh;
 172         unsigned short  ldt, __ldth;
 173         unsigned short  trace, bitmap;
 174         unsigned long   io_bitmap[IO_BITMAP_SIZE+1];
 175         unsigned long   tr;
 176         unsigned long   cr2, trap_no, error_code;
 177         union i387_union i387;
 178 };
 179 
 180 #define INIT_TSS  { \
 181         0,0, \
 182         sizeof(init_kernel_stack) + (long) &init_kernel_stack, \
 183         KERNEL_DS, 0, \
 184         0,0,0,0,0,0, \
 185         (long) &swapper_pg_dir, \
 186         0,0,0,0,0,0,0,0,0,0, \
 187         USER_DS,0,USER_DS,0,USER_DS,0,USER_DS,0,USER_DS,0,USER_DS,0, \
 188         _LDT(0),0, \
 189         0, 0x8000, \
 190         {~0, }, /* ioperm */ \
 191         _TSS(0), 0, 0,0, \
 192         { { 0, }, }  /* 387 state */ \
 193 }
 194 
 195 struct files_struct {
 196         int count;
 197         fd_set close_on_exec;
 198         struct file * fd[NR_OPEN];
 199 };
 200 
 201 #define INIT_FILES { \
 202         0, \
 203         { { 0, } }, \
 204         { NULL, } \
 205 }
 206 
 207 struct fs_struct {
 208         int count;
 209         unsigned short umask;
 210         struct inode * root, * pwd;
 211 };
 212 
 213 #define INIT_FS { \
 214         0, \
 215         0022, \
 216         NULL, NULL \
 217 }
 218 
 219 struct mm_struct {
 220         int count;
 221         unsigned long start_code, end_code, end_data;
 222         unsigned long start_brk, brk, start_stack, start_mmap;
 223         unsigned long arg_start, arg_end, env_start, env_end;
 224         unsigned long rss;
 225         unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 226         int swappable:1;
 227         unsigned long swap_address;
 228         unsigned long old_maj_flt;      /* old value of maj_flt */
 229         unsigned long dec_flt;          /* page fault count of the last time */
 230         unsigned long swap_cnt;         /* number of pages to swap on next pass */
 231         struct vm_area_struct * mmap;
 232 };
 233 
 234 #define INIT_MMAP { &init_task, 0, 0x40000000, PAGE_SHARED, }
 235 
 236 #define INIT_MM { \
 237                 0, \
 238                 0, 0, 0, \
 239                 0, 0, 0, 0, \
 240                 0, 0, 0, 0, \
 241                 0, \
 242 /* ?_flt */     0, 0, 0, 0, \
 243                 0, \
 244 /* swap */      0, 0, 0, 0, \
 245                 &init_mmap }
 246 
 247 struct task_struct {
 248 /* these are hardcoded - don't touch */
 249         volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
 250         long counter;
 251         long priority;
 252         unsigned long signal;
 253         unsigned long blocked;  /* bitmap of masked signals */
 254         unsigned long flags;    /* per process flags, defined below */
 255         int errno;
 256         int debugreg[8];  /* Hardware debugging registers */
 257         struct exec_domain *exec_domain;
 258 /* various fields */
 259         struct linux_binfmt *binfmt;
 260         struct task_struct *next_task, *prev_task;
 261         struct sigaction sigaction[32];
 262         unsigned long saved_kernel_stack;
 263         unsigned long kernel_stack_page;
 264         int exit_code, exit_signal;
 265         unsigned long personality;
 266         int dumpable:1;
 267         int did_exec:1;
 268         int pid,pgrp,session,leader;
 269         int     groups[NGROUPS];
 270         /* 
 271          * pointers to (original) parent process, youngest child, younger sibling,
 272          * older sibling, respectively.  (p->father can be replaced with 
 273          * p->p_pptr->pid)
 274          */
 275         struct task_struct *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
 276         struct wait_queue *wait_chldexit;       /* for wait4() */
 277         unsigned short uid,euid,suid,fsuid;
 278         unsigned short gid,egid,sgid,fsgid;
 279         unsigned long timeout;
 280         unsigned long it_real_value, it_prof_value, it_virt_value;
 281         unsigned long it_real_incr, it_prof_incr, it_virt_incr;
 282         long utime, stime, cutime, cstime, start_time;
 283         struct rlimit rlim[RLIM_NLIMITS]; 
 284         unsigned short used_math;
 285         char comm[16];
 286 /* virtual 86 mode stuff */
 287         struct vm86_struct * vm86_info;
 288         unsigned long screen_bitmap;
 289         unsigned long v86flags, v86mask, v86mode;
 290 /* file system info */
 291         int link_count;
 292         struct tty_struct *tty; /* NULL if no tty */
 293 /* ipc stuff */
 294         struct sem_undo *semundo;
 295 /* ldt for this task - used by Wine.  If NULL, default_ldt is used */
 296         struct desc_struct *ldt;
 297 /* tss for this task */
 298         struct tss_struct tss;
 299 /* filesystem information */
 300         struct fs_struct fs[1];
 301 /* open file information */
 302         struct files_struct files[1];
 303 /* memory management info */
 304         struct mm_struct mm[1];
 305 };
 306 
 307 /*
 308  * Per process flags
 309  */
 310 #define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
 311                                         /* Not implemented yet, only for 486*/
 312 #define PF_PTRACED      0x00000010      /* set if ptrace (0) has been called. */
 313 #define PF_TRACESYS     0x00000020      /* tracing system calls */
 314 
 315 /*
 316  * cloning flags:
 317  */
 318 #define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
 319 #define COPYVM          0x00000100      /* set if VM copy desired (like normal fork()) */
 320 #define COPYFD          0x00000200      /* set if fd's should be copied, not shared (NI) */
 321 
 322 /*
 323  *  INIT_TASK is used to set up the first task table, touch at
 324  * your own risk!. Base=0, limit=0x1fffff (=2MB)
 325  */
 326 #define INIT_TASK \
 327 /* state etc */ { 0,15,15,0,0,0,0, \
 328 /* debugregs */ { 0, },            \
 329 /* exec domain */&default_exec_domain, \
 330 /* binfmt */    NULL, \
 331 /* schedlink */ &init_task,&init_task, \
 332 /* signals */   {{ 0, },}, \
 333 /* stack */     0,(unsigned long) &init_kernel_stack, \
 334 /* ec,brk... */ 0,0,0,0,0, \
 335 /* pid etc.. */ 0,0,0,0, \
 336 /* suppl grps*/ {NOGROUP,}, \
 337 /* proc links*/ &init_task,&init_task,NULL,NULL,NULL,NULL, \
 338 /* uid etc */   0,0,0,0,0,0,0,0, \
 339 /* timeout */   0,0,0,0,0,0,0,0,0,0,0,0, \
 340 /* rlimits */   { {LONG_MAX, LONG_MAX}, {LONG_MAX, LONG_MAX},  \
 341                   {LONG_MAX, LONG_MAX}, {LONG_MAX, LONG_MAX},  \
 342                   {       0, LONG_MAX}, {LONG_MAX, LONG_MAX}}, \
 343 /* math */      0, \
 344 /* comm */      "swapper", \
 345 /* vm86_info */ NULL, 0, 0, 0, 0, \
 346 /* fs info */   0,NULL, \
 347 /* ipc */       NULL, \
 348 /* ldt */       NULL, \
 349 /* tss */       INIT_TSS, \
 350 /* fs */        { INIT_FS }, \
 351 /* files */     { INIT_FILES }, \
 352 /* mm */        { INIT_MM } \
 353 }
 354 
 355 #ifdef __KERNEL__
 356 
 357 extern struct task_struct init_task;
 358 extern struct task_struct *task[NR_TASKS];
 359 extern struct task_struct *last_task_used_math;
 360 extern struct task_struct *current;
 361 extern unsigned long volatile jiffies;
 362 extern unsigned long itimer_ticks;
 363 extern unsigned long itimer_next;
 364 extern struct timeval xtime;
 365 extern int need_resched;
 366 
 367 #define CURRENT_TIME (xtime.tv_sec)
 368 
 369 extern void sleep_on(struct wait_queue ** p);
 370 extern void interruptible_sleep_on(struct wait_queue ** p);
 371 extern void wake_up(struct wait_queue ** p);
 372 extern void wake_up_interruptible(struct wait_queue ** p);
 373 
 374 extern void notify_parent(struct task_struct * tsk);
 375 extern int send_sig(unsigned long sig,struct task_struct * p,int priv);
 376 extern int in_group_p(gid_t grp);
 377 
 378 extern int request_irq(unsigned int irq,void (*handler)(int), unsigned long flags, const char *device);
 379 extern void free_irq(unsigned int irq);
 380 
 381 /*
 382  * Entry into gdt where to find first TSS. GDT layout:
 383  *   0 - nul
 384  *   1 - kernel code segment
 385  *   2 - kernel data segment
 386  *   3 - user code segment
 387  *   4 - user data segment
 388  * ...
 389  *   8 - TSS #0
 390  *   9 - LDT #0
 391  *  10 - TSS #1
 392  *  11 - LDT #1
 393  */
 394 #define FIRST_TSS_ENTRY 8
 395 #define FIRST_LDT_ENTRY (FIRST_TSS_ENTRY+1)
 396 #define _TSS(n) ((((unsigned long) n)<<4)+(FIRST_TSS_ENTRY<<3))
 397 #define _LDT(n) ((((unsigned long) n)<<4)+(FIRST_LDT_ENTRY<<3))
 398 #define load_TR(n) __asm__("ltr %%ax": /* no output */ :"a" (_TSS(n)))
 399 #define load_ldt(n) __asm__("lldt %%ax": /* no output */ :"a" (_LDT(n)))
 400 #define store_TR(n) \
 401 __asm__("str %%ax\n\t" \
 402         "subl %2,%%eax\n\t" \
 403         "shrl $4,%%eax" \
 404         :"=a" (n) \
 405         :"0" (0),"i" (FIRST_TSS_ENTRY<<3))
 406 /*
 407  *      switch_to(n) should switch tasks to task nr n, first
 408  * checking that n isn't the current task, in which case it does nothing.
 409  * This also clears the TS-flag if the task we switched to has used
 410  * tha math co-processor latest.
 411  */
 412 #define switch_to(tsk) \
 413 __asm__("cli\n\t" \
 414         "xchgl %%ecx,_current\n\t" \
 415         "ljmp %0\n\t" \
 416         "sti\n\t" \
 417         "cmpl %%ecx,_last_task_used_math\n\t" \
 418         "jne 1f\n\t" \
 419         "clts\n" \
 420         "1:" \
 421         : /* no output */ \
 422         :"m" (*(((char *)&tsk->tss.tr)-4)), \
 423          "c" (tsk) \
 424         :"cx")
 425 
 426 #define _set_base(addr,base) \
 427 __asm__("movw %%dx,%0\n\t" \
 428         "rorl $16,%%edx\n\t" \
 429         "movb %%dl,%1\n\t" \
 430         "movb %%dh,%2" \
 431         : /* no output */ \
 432         :"m" (*((addr)+2)), \
 433          "m" (*((addr)+4)), \
 434          "m" (*((addr)+7)), \
 435          "d" (base) \
 436         :"dx")
 437 
 438 #define _set_limit(addr,limit) \
 439 __asm__("movw %%dx,%0\n\t" \
 440         "rorl $16,%%edx\n\t" \
 441         "movb %1,%%dh\n\t" \
 442         "andb $0xf0,%%dh\n\t" \
 443         "orb %%dh,%%dl\n\t" \
 444         "movb %%dl,%1" \
 445         : /* no output */ \
 446         :"m" (*(addr)), \
 447          "m" (*((addr)+6)), \
 448          "d" (limit) \
 449         :"dx")
 450 
 451 #define set_base(ldt,base) _set_base( ((char *)&(ldt)) , base )
 452 #define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , (limit-1)>>12 )
 453 
 454 /*
 455  * The wait-queues are circular lists, and you have to be *very* sure
 456  * to keep them correct. Use only these two functions to add/remove
 457  * entries in the queues.
 458  */
 459 extern inline void add_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 460 {
 461         unsigned long flags;
 462 
 463 #ifdef DEBUG
 464         if (wait->next) {
 465                 unsigned long pc;
 466                 __asm__ __volatile__("call 1f\n"
 467                         "1:\tpopl %0":"=r" (pc));
 468                 printk("add_wait_queue (%08x): wait->next = %08x\n",pc,(unsigned long) wait->next);
 469         }
 470 #endif
 471         save_flags(flags);
 472         cli();
 473         if (!*p) {
 474                 wait->next = wait;
 475                 *p = wait;
 476         } else {
 477                 wait->next = (*p)->next;
 478                 (*p)->next = wait;
 479         }
 480         restore_flags(flags);
 481 }
 482 
 483 extern inline void remove_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 484 {
 485         unsigned long flags;
 486         struct wait_queue * tmp;
 487 #ifdef DEBUG
 488         unsigned long ok = 0;
 489 #endif
 490 
 491         save_flags(flags);
 492         cli();
 493         if ((*p == wait) &&
 494 #ifdef DEBUG
 495             (ok = 1) &&
 496 #endif
 497             ((*p = wait->next) == wait)) {
 498                 *p = NULL;
 499         } else {
 500                 tmp = wait;
 501                 while (tmp->next != wait) {
 502                         tmp = tmp->next;
 503 #ifdef DEBUG
 504                         if (tmp == *p)
 505                                 ok = 1;
 506 #endif
 507                 }
 508                 tmp->next = wait->next;
 509         }
 510         wait->next = NULL;
 511         restore_flags(flags);
 512 #ifdef DEBUG
 513         if (!ok) {
 514                 printk("removed wait_queue not on list.\n");
 515                 printk("list = %08x, queue = %08x\n",(unsigned long) p, (unsigned long) wait);
 516                 __asm__("call 1f\n1:\tpopl %0":"=r" (ok));
 517                 printk("eip = %08x\n",ok);
 518         }
 519 #endif
 520 }
 521 
 522 extern inline void select_wait(struct wait_queue ** wait_address, select_table * p)
     /*  */
 523 {
 524         struct select_table_entry * entry;
 525 
 526         if (!p || !wait_address)
 527                 return;
 528         if (p->nr >= __MAX_SELECT_TABLE_ENTRIES)
 529                 return;
 530         entry = p->entry + p->nr;
 531         entry->wait_address = wait_address;
 532         entry->wait.task = current;
 533         entry->wait.next = NULL;
 534         add_wait_queue(wait_address,&entry->wait);
 535         p->nr++;
 536 }
 537 
 538 extern void __down(struct semaphore * sem);
 539 
 540 /*
 541  * These are not yet interrupt-safe
 542  */
 543 extern inline void down(struct semaphore * sem)
     /*  */
 544 {
 545         if (sem->count <= 0)
 546                 __down(sem);
 547         sem->count--;
 548 }
 549 
 550 extern inline void up(struct semaphore * sem)
     /*  */
 551 {
 552         sem->count++;
 553         wake_up(&sem->wait);
 554 }       
 555 
 556 static inline unsigned long _get_base(char * addr)
     /*  */
 557 {
 558         unsigned long __base;
 559         __asm__("movb %3,%%dh\n\t"
 560                 "movb %2,%%dl\n\t"
 561                 "shll $16,%%edx\n\t"
 562                 "movw %1,%%dx"
 563                 :"=&d" (__base)
 564                 :"m" (*((addr)+2)),
 565                  "m" (*((addr)+4)),
 566                  "m" (*((addr)+7)));
 567         return __base;
 568 }
 569 
 570 #define get_base(ldt) _get_base( ((char *)&(ldt)) )
 571 
 572 static inline unsigned long get_limit(unsigned long segment)
     /*  */
 573 {
 574         unsigned long __limit;
 575         __asm__("lsll %1,%0"
 576                 :"=r" (__limit):"r" (segment));
 577         return __limit+1;
 578 }
 579 
 580 #define REMOVE_LINKS(p) do { unsigned long flags; \
 581         save_flags(flags) ; cli(); \
 582         (p)->next_task->prev_task = (p)->prev_task; \
 583         (p)->prev_task->next_task = (p)->next_task; \
 584         restore_flags(flags); \
 585         if ((p)->p_osptr) \
 586                 (p)->p_osptr->p_ysptr = (p)->p_ysptr; \
 587         if ((p)->p_ysptr) \
 588                 (p)->p_ysptr->p_osptr = (p)->p_osptr; \
 589         else \
 590                 (p)->p_pptr->p_cptr = (p)->p_osptr; \
 591         } while (0)
 592 
 593 #define SET_LINKS(p) do { unsigned long flags; \
 594         save_flags(flags); cli(); \
 595         (p)->next_task = &init_task; \
 596         (p)->prev_task = init_task.prev_task; \
 597         init_task.prev_task->next_task = (p); \
 598         init_task.prev_task = (p); \
 599         restore_flags(flags); \
 600         (p)->p_ysptr = NULL; \
 601         if (((p)->p_osptr = (p)->p_pptr->p_cptr) != NULL) \
 602                 (p)->p_osptr->p_ysptr = p; \
 603         (p)->p_pptr->p_cptr = p; \
 604         } while (0)
 605 
 606 #define for_each_task(p) \
 607         for (p = &init_task ; (p = p->next_task) != &init_task ; )
 608 
 609 /*
 610  * This is the ldt that every process will get unless we need
 611  * something other than this.
 612  */
 613 extern struct desc_struct default_ldt;
 614 
 615 /* This special macro can be used to load a debugging register */
 616 
 617 #define loaddebug(register) \
 618                 __asm__("movl %0,%%edx\n\t" \
 619                         "movl %%edx,%%db" #register "\n\t" \
 620                         : /* no output */ \
 621                         :"m" (current->debugreg[register]) \
 622                         :"dx");
 623 
 624 #endif /* __KERNEL__ */
 625 
 626 #endif
/* */
root/include/linux/sched.h

INCLUDED FROM

DEFINITIONS
