include/linux/sched.h

/* */
This source file includes following definitions.
add_wait_queue
remove_wait_queue
select_wait
_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 
  13 #define HZ 100
  14 
  15 /*
  16  * This is the maximum nr of tasks - change it if you need to
  17  */
  18 #define NR_TASKS        64
  19 
  20 /*
  21  * User space process size: 3GB. This is hardcoded into a few places,
  22  * so don't change it unless you know what you are doing.
  23  */
  24 #define TASK_SIZE       0xc0000000
  25 
  26 /*
  27  * Size of io_bitmap in longwords: 32 is ports 0-0x3ff.
  28  */
  29 #define IO_BITMAP_SIZE  32
  30 
  31 /*
  32  * These are the constant used to fake the fixed-point load-average
  33  * counting. Some notes:
  34  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
  35  *    a load-average precision of 10 bits integer + 11 bits fractional
  36  *  - if you want to count load-averages more often, you need more
  37  *    precision, or rounding will get you. With 2-second counting freq,
  38  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
  39  *    11 bit fractions.
  40  */
  41 extern unsigned long avenrun[];         /* Load averages */
  42 
  43 #define FSHIFT          11              /* nr of bits of precision */
  44 #define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
  45 #define LOAD_FREQ       (5*HZ)          /* 5 sec intervals */
  46 #define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
  47 #define EXP_5           2014            /* 1/exp(5sec/5min) */
  48 #define EXP_15          2037            /* 1/exp(5sec/15min) */
  49 
  50 #define CALC_LOAD(load,exp,n) \
  51         load *= exp; \
  52         load += n*(FIXED_1-exp); \
  53         load >>= FSHIFT;
  54 
  55 #define CT_TO_SECS(x)   ((x) / HZ)
  56 #define CT_TO_USECS(x)  (((x) % HZ) * 1000000/HZ)
  57 
  58 #define FIRST_TASK task[0]
  59 #define LAST_TASK task[NR_TASKS-1]
  60 
  61 #include <linux/head.h>
  62 #include <linux/fs.h>
  63 #include <linux/mm.h>
  64 #include <linux/signal.h>
  65 #include <linux/time.h>
  66 #include <linux/param.h>
  67 #include <linux/resource.h>
  68 #include <linux/vm86.h>
  69 #include <linux/math_emu.h>
  70 
  71 #define TASK_RUNNING            0
  72 #define TASK_INTERRUPTIBLE      1
  73 #define TASK_UNINTERRUPTIBLE    2
  74 #define TASK_ZOMBIE             3
  75 #define TASK_STOPPED            4
  76 #define TASK_SWAPPING           5
  77 
  78 #ifndef NULL
  79 #define NULL ((void *) 0)
  80 #endif
  81 
  82 #define MAX_SHARED_LIBS 16
  83 
  84 extern void sched_init(void);
  85 extern void show_state(void);
  86 extern void schedule(void);
  87 extern void trap_init(void);
  88 extern void panic(const char * str);
  89 
  90 typedef int (*fn_ptr)();
  91 
  92 union i387_union {
  93         struct i387_hard_struct {
  94                 long    cwd;
  95                 long    swd;
  96                 long    twd;
  97                 long    fip;
  98                 long    fcs;
  99                 long    foo;
 100                 long    fos;
 101                 long    st_space[20];   /* 8*10 bytes for each FP-reg = 80 bytes */
 102         } hard;
 103         struct i387_soft_struct {
 104                 long    cwd;
 105                 long    swd;
 106                 long    twd;
 107                 long    fip;
 108                 long    fcs;
 109                 long    foo;
 110                 long    fos;
 111                 long    top;
 112                 struct fpu_reg  regs[8];        /* 8*16 bytes for each FP-reg = 128 bytes */
 113                 unsigned char   lookahead;
 114                 struct info     *info;
 115                 unsigned long   entry_eip;
 116         } soft;
 117 };
 118 
 119 struct tss_struct {
 120         unsigned long   back_link;      /* 16 high bits zero */
 121         unsigned long   esp0;
 122         unsigned long   ss0;            /* 16 high bits zero */
 123         unsigned long   esp1;
 124         unsigned long   ss1;            /* 16 high bits zero */
 125         unsigned long   esp2;
 126         unsigned long   ss2;            /* 16 high bits zero */
 127         unsigned long   cr3;
 128         unsigned long   eip;
 129         unsigned long   eflags;
 130         unsigned long   eax,ecx,edx,ebx;
 131         unsigned long   esp;
 132         unsigned long   ebp;
 133         unsigned long   esi;
 134         unsigned long   edi;
 135         unsigned long   es;             /* 16 high bits zero */
 136         unsigned long   cs;             /* 16 high bits zero */
 137         unsigned long   ss;             /* 16 high bits zero */
 138         unsigned long   ds;             /* 16 high bits zero */
 139         unsigned long   fs;             /* 16 high bits zero */
 140         unsigned long   gs;             /* 16 high bits zero */
 141         unsigned long   ldt;            /* 16 high bits zero */
 142         unsigned long   trace_bitmap;   /* bits: trace 0, bitmap 16-31 */
 143         unsigned long   io_bitmap[IO_BITMAP_SIZE];
 144         union i387_union i387;
 145 };
 146 
 147 struct task_struct {
 148 /* these are hardcoded - don't touch */
 149         long state;     /* -1 unrunnable, 0 runnable, >0 stopped */
 150         long counter;
 151         long priority;
 152         long signal;
 153         struct sigaction sigaction[32];
 154         long blocked;   /* bitmap of masked signals */
 155         unsigned long saved_kernel_stack;
 156         unsigned long kernel_stack_page;
 157         unsigned int flags;     /* per process flags, defined below */
 158 /* various fields */
 159         int exit_code;
 160         int dumpable:1;
 161         int swappable:1;
 162         unsigned long start_code,end_code,end_data,brk,start_stack;
 163         unsigned long arg_start, arg_end, env_start, env_end;
 164         long pid,pgrp,session,leader;
 165         int     groups[NGROUPS];
 166         /* 
 167          * pointers to (original) parent process, youngest child, younger sibling,
 168          * older sibling, respectively.  (p->father can be replaced with 
 169          * p->p_pptr->pid)
 170          */
 171         struct task_struct *p_opptr,*p_pptr, *p_cptr, *p_ysptr, *p_osptr;
 172         /*
 173          * For ease of programming... Normal sleeps don't need to
 174          * keep track of a wait-queue: every task has an entry of it's own
 175          */
 176         unsigned short uid,euid,suid;
 177         unsigned short gid,egid,sgid;
 178         unsigned long timeout;
 179         unsigned long it_real_value, it_prof_value, it_virt_value;
 180         unsigned long it_real_incr, it_prof_incr, it_virt_incr;
 181         long utime,stime,cutime,cstime,start_time;
 182         unsigned long min_flt, maj_flt;
 183         unsigned long cmin_flt, cmaj_flt;
 184         struct rlimit rlim[RLIM_NLIMITS]; 
 185         unsigned short used_math;
 186         unsigned short rss;     /* number of resident pages */
 187         char comm[16];
 188         struct vm86_struct * vm86_info;
 189         unsigned long screen_bitmap;
 190 /* file system info */
 191         int link_count;
 192         int tty;                /* -1 if no tty, so it must be signed */
 193         unsigned short umask;
 194         struct inode * pwd;
 195         struct inode * root;
 196         struct inode * executable;
 197         struct vm_area_struct * mmap;
 198         struct {
 199                 struct inode * library;
 200                 unsigned long start;
 201                 unsigned long length;
 202                 unsigned long bss;
 203         } libraries[MAX_SHARED_LIBS];
 204         int numlibraries;
 205         struct file * filp[NR_OPEN];
 206         fd_set close_on_exec;
 207 /* ldt for this task 0 - zero 1 - cs 2 - ds&ss, rest unused */
 208         struct desc_struct ldt[32];
 209 /* tss for this task */
 210         struct tss_struct tss;
 211 };
 212 
 213 /*
 214  * Per process flags
 215  */
 216 #define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
 217                                         /* Not implemented yet, only for 486*/
 218 #define PF_PTRACED      0x00000010      /* set if ptrace (0) has been called. */
 219 #define PF_TRACESYS     0x00000020      /* tracing system calls */
 220 
 221 /*
 222  *  INIT_TASK is used to set up the first task table, touch at
 223  * your own risk!. Base=0, limit=0x9ffff (=640kB)
 224  */
 225 #define INIT_TASK \
 226 /* state etc */ { 0,15,15, \
 227 /* signals */   0,{{ 0, },},0,0,0, \
 228 /* flags */     0, \
 229 /* ec,brk... */ 0,0,0,0,0,0,0,0, \
 230 /* argv.. */    0,0,0,0, \
 231 /* pid etc.. */ 0,0,0,0, \
 232 /* suppl grps*/ {NOGROUP,}, \
 233 /* proc links*/ &init_task,&init_task,NULL,NULL,NULL, \
 234 /* uid etc */   0,0,0,0,0,0, \
 235 /* timeout */   0,0,0,0,0,0,0,0,0,0,0,0, \
 236 /* min_flt */   0,0,0,0, \
 237 /* rlimits */   { {0x7fffffff, 0x7fffffff}, {0x7fffffff, 0x7fffffff},  \
 238                   {0x7fffffff, 0x7fffffff}, {0x7fffffff, 0x7fffffff}, \
 239                   {0x7fffffff, 0x7fffffff}, {0x7fffffff, 0x7fffffff}}, \
 240 /* math */      0, \
 241 /* rss */       2, \
 242 /* comm */      "swapper", \
 243 /* vm86_info */ NULL, 0, \
 244 /* fs info */   0,-1,0022,NULL,NULL,NULL,NULL, \
 245 /* libraries */ { { NULL, 0, 0, 0}, }, 0, \
 246 /* filp */      {NULL,}, \
 247 /* cloe */      {{ 0, }}, \
 248                 { \
 249                         {0,0}, \
 250 /* ldt */               {0x9f,0xc0c0fa00}, \
 251                         {0x9f,0xc0c0f200}, \
 252                 }, \
 253 /*tss*/ {0,sizeof(init_kernel_stack) + (long) &init_kernel_stack, \
 254          0x10,0,0,0,0,(long) &swapper_pg_dir,\
 255          0,0,0,0,0,0,0,0, \
 256          0,0,0x17,0x17,0x17,0x17,0x17,0x17, \
 257          _LDT(0),0x80000000,{0xffffffff}, \
 258                 { { 0, }, } \
 259         } \
 260 }
 261 
 262 extern struct task_struct *task[NR_TASKS];
 263 extern struct task_struct *last_task_used_math;
 264 extern struct task_struct *current;
 265 extern unsigned long volatile jiffies;
 266 extern unsigned long startup_time;
 267 extern int jiffies_offset;
 268 extern int need_resched;
 269 extern int hard_math;
 270 
 271 #define CURRENT_TIME (startup_time+(jiffies+jiffies_offset)/HZ)
 272 
 273 extern void add_timer(long jiffies, void (*fn)(void));
 274 
 275 extern void sleep_on(struct wait_queue ** p);
 276 extern void interruptible_sleep_on(struct wait_queue ** p);
 277 extern void wake_up(struct wait_queue ** p);
 278 extern void wake_up_interruptible(struct wait_queue ** p);
 279 
 280 extern int send_sig(long sig,struct task_struct * p,int priv);
 281 extern int in_group_p(gid_t grp);
 282 
 283 extern int request_irq(unsigned int irq,void (*handler)(int));
 284 extern void free_irq(unsigned int irq);
 285 extern int irqaction(unsigned int irq,struct sigaction * new);
 286 
 287 /*
 288  * Entry into gdt where to find first TSS. 0-nul, 1-cs, 2-ds, 3-syscall
 289  * 4-TSS0, 5-LDT0, 6-TSS1 etc ...
 290  */
 291 #define FIRST_TSS_ENTRY 4
 292 #define FIRST_LDT_ENTRY (FIRST_TSS_ENTRY+1)
 293 #define _TSS(n) ((((unsigned long) n)<<4)+(FIRST_TSS_ENTRY<<3))
 294 #define _LDT(n) ((((unsigned long) n)<<4)+(FIRST_LDT_ENTRY<<3))
 295 #define load_TR(n) __asm__("ltr %%ax"::"a" (_TSS(n)))
 296 #define load_ldt(n) __asm__("lldt %%ax"::"a" (_LDT(n)))
 297 #define store_TR(n) \
 298 __asm__("str %%ax\n\t" \
 299         "subl %2,%%eax\n\t" \
 300         "shrl $4,%%eax" \
 301         :"=a" (n) \
 302         :"0" (0),"i" (FIRST_TSS_ENTRY<<3))
 303 /*
 304  *      switch_to(n) should switch tasks to task nr n, first
 305  * checking that n isn't the current task, in which case it does nothing.
 306  * This also clears the TS-flag if the task we switched to has used
 307  * tha math co-processor latest.
 308  */
 309 #define switch_to(n) {\
 310 struct {long a,b;} __tmp; \
 311 __asm__("cmpl %%ecx,_current\n\t" \
 312         "je 1f\n\t" \
 313         "movw %%dx,%1\n\t" \
 314         "cli\n\t" \
 315         "xchgl %%ecx,_current\n\t" \
 316         "ljmp %0\n\t" \
 317         "sti\n\t" \
 318         "cmpl %%ecx,_last_task_used_math\n\t" \
 319         "jne 1f\n\t" \
 320         "clts\n" \
 321         "1:" \
 322         ::"m" (*&__tmp.a),"m" (*&__tmp.b), \
 323         "d" (_TSS(n)),"c" ((long) task[n]) \
 324         :"cx"); \
 325 }
 326 
 327 #define PAGE_ALIGN(n) (((n)+0xfff)&0xfffff000)
 328 
 329 #define _set_base(addr,base) \
 330 __asm__("movw %%dx,%0\n\t" \
 331         "rorl $16,%%edx\n\t" \
 332         "movb %%dl,%1\n\t" \
 333         "movb %%dh,%2" \
 334         ::"m" (*((addr)+2)), \
 335           "m" (*((addr)+4)), \
 336           "m" (*((addr)+7)), \
 337           "d" (base) \
 338         :"dx")
 339 
 340 #define _set_limit(addr,limit) \
 341 __asm__("movw %%dx,%0\n\t" \
 342         "rorl $16,%%edx\n\t" \
 343         "movb %1,%%dh\n\t" \
 344         "andb $0xf0,%%dh\n\t" \
 345         "orb %%dh,%%dl\n\t" \
 346         "movb %%dl,%1" \
 347         ::"m" (*(addr)), \
 348           "m" (*((addr)+6)), \
 349           "d" (limit) \
 350         :"dx")
 351 
 352 #define set_base(ldt,base) _set_base( ((char *)&(ldt)) , base )
 353 #define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , (limit-1)>>12 )
 354 
 355 /*
 356  * The wait-queues are circular lists, and you have to be *very* sure
 357  * to keep them correct. Use only these two functions to add/remove
 358  * entries in the queues.
 359  */
 360 extern inline void add_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 361 {
 362         unsigned long flags;
 363 
 364 #ifdef DEBUG
 365         if (wait->next) {
 366                 unsigned long pc;
 367                 __asm__ __volatile__("call 1f\n"
 368                         "1:\tpopl %0":"=r" (pc));
 369                 printk("add_wait_queue (%08x): wait->next = %08x\n",pc,wait->next);
 370         }
 371 #endif
 372         __asm__ __volatile__("pushfl ; popl %0 ; cli":"=r" (flags));
 373         if (!*p) {
 374                 wait->next = wait;
 375                 *p = wait;
 376         } else {
 377                 wait->next = (*p)->next;
 378                 (*p)->next = wait;
 379         }
 380         __asm__ __volatile__("pushl %0 ; popfl"::"r" (flags));
 381 }
 382 
 383 extern inline void remove_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 384 {
 385         unsigned long flags;
 386         struct wait_queue * tmp;
 387 #ifdef DEBUG
 388         unsigned long ok = 0;
 389 #endif
 390 
 391         __asm__ __volatile__("pushfl ; popl %0 ; cli":"=r" (flags));
 392         if ((*p == wait) &&
 393 #ifdef DEBUG
 394             (ok = 1) &&
 395 #endif
 396             ((*p = wait->next) == wait)) {
 397                 *p = NULL;
 398         } else {
 399                 tmp = wait;
 400                 while (tmp->next != wait) {
 401                         tmp = tmp->next;
 402 #ifdef DEBUG
 403                         if (tmp == *p)
 404                                 ok = 1;
 405 #endif
 406                 }
 407                 tmp->next = wait->next;
 408         }
 409         wait->next = NULL;
 410         __asm__ __volatile__("pushl %0 ; popfl"::"r" (flags));
 411 #ifdef DEBUG
 412         if (!ok) {
 413                 printk("removed wait_queue not on list.\n");
 414                 printk("list = %08x, queue = %08x\n",p,wait);
 415                 __asm__("call 1f\n1:\tpopl %0":"=r" (ok));
 416                 printk("eip = %08x\n",ok);
 417         }
 418 #endif
 419 }
 420 
 421 extern inline void select_wait(struct wait_queue ** wait_address, select_table * p)
     /*  */
 422 {
 423         struct select_table_entry * entry;
 424 
 425         if (!p || !wait_address)
 426                 return;
 427         if (p->nr >= __MAX_SELECT_TABLE_ENTRIES)
 428                 return;
 429         entry = p->entry + p->nr;
 430         entry->wait_address = wait_address;
 431         entry->wait.task = current;
 432         entry->wait.next = NULL;
 433         add_wait_queue(wait_address,&entry->wait);
 434         p->nr++;
 435 }
 436 
 437 static inline unsigned long _get_base(char * addr)
     /*  */
 438 {
 439         unsigned long __base;
 440         __asm__("movb %3,%%dh\n\t"
 441                 "movb %2,%%dl\n\t"
 442                 "shll $16,%%edx\n\t"
 443                 "movw %1,%%dx"
 444                 :"=&d" (__base)
 445                 :"m" (*((addr)+2)),
 446                  "m" (*((addr)+4)),
 447                  "m" (*((addr)+7)));
 448         return __base;
 449 }
 450 
 451 #define get_base(ldt) _get_base( ((char *)&(ldt)) )
 452 
 453 static inline unsigned long get_limit(unsigned long segment)
     /*  */
 454 {
 455         unsigned long __limit;
 456         __asm__("lsll %1,%0"
 457                 :"=r" (__limit):"r" (segment));
 458         return __limit+1;
 459 }
 460 
 461 #define REMOVE_LINKS(p) \
 462         if ((p)->p_osptr) \
 463                 (p)->p_osptr->p_ysptr = (p)->p_ysptr; \
 464         if ((p)->p_ysptr) \
 465                 (p)->p_ysptr->p_osptr = (p)->p_osptr; \
 466         else \
 467                 (p)->p_pptr->p_cptr = (p)->p_osptr
 468 
 469 #define SET_LINKS(p) \
 470         (p)->p_ysptr = NULL; \
 471         if (((p)->p_osptr = (p)->p_pptr->p_cptr) != NULL) \
 472                 (p)->p_osptr->p_ysptr = p; \
 473         (p)->p_pptr->p_cptr = p
 474 
 475 #endif
/* */
root/include/linux/sched.h

INCLUDED FROM

DEFINITIONS
