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

INCLUDED FROM

DEFINITIONS
