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 struct sched_param {
  96         int sched_priority;
  97 };
  98 
  99 #ifndef NULL
 100 #define NULL ((void *) 0)
 101 #endif
 102 
 103 #ifdef __KERNEL__
 104 
 105 #define barrier() __asm__("": : :"memory")
 106 
 107 extern void sched_init(void);
 108 extern void show_state(void);
 109 extern void trap_init(void);
 110 
 111 asmlinkage void schedule(void);
 112 
 113 struct files_struct {
 114         int count;
 115         fd_set close_on_exec;
 116         struct file * fd[NR_OPEN];
 117 };
 118 
 119 #define INIT_FILES { \
 120         1, \
 121         { { 0, } }, \
 122         { NULL, } \
 123 }
 124 
 125 struct fs_struct {
 126         int count;
 127         unsigned short umask;
 128         struct inode * root, * pwd;
 129 };
 130 
 131 #define INIT_FS { \
 132         1, \
 133         0022, \
 134         NULL, NULL \
 135 }
 136 
 137 struct mm_struct {
 138         int count;
 139         pgd_t * pgd;
 140         unsigned long context;
 141         unsigned long start_code, end_code, start_data, end_data;
 142         unsigned long start_brk, brk, start_stack, start_mmap;
 143         unsigned long arg_start, arg_end, env_start, env_end;
 144         unsigned long rss, total_vm, locked_vm;
 145         unsigned long def_flags;
 146         struct vm_area_struct * mmap;
 147         struct vm_area_struct * mmap_avl;
 148 };
 149 
 150 #define INIT_MM { \
 151                 1, \
 152                 swapper_pg_dir, \
 153                 0, \
 154                 0, 0, 0, 0, \
 155                 0, 0, 0, 0, \
 156                 0, 0, 0, 0, \
 157                 0, 0, 0, \
 158                 0, \
 159                 &init_mmap, &init_mmap }
 160 
 161 struct signal_struct {
 162         int count;
 163         struct sigaction action[32];
 164 };
 165 
 166 #define INIT_SIGNALS { \
 167                 1, \
 168                 { {0,}, } }
 169 
 170 struct task_struct {
 171 /* these are hardcoded - don't touch */
 172         volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
 173         long counter;
 174         long priority;
 175         unsigned long signal;
 176         unsigned long blocked;  /* bitmap of masked signals */
 177         unsigned long flags;    /* per process flags, defined below */
 178         int errno;
 179         long debugreg[8];  /* Hardware debugging registers */
 180         struct exec_domain *exec_domain;
 181 /* various fields */
 182         struct linux_binfmt *binfmt;
 183         struct task_struct *next_task, *prev_task;
 184         struct task_struct *next_run,  *prev_run;
 185         unsigned long saved_kernel_stack;
 186         unsigned long kernel_stack_page;
 187         int exit_code, exit_signal;
 188         unsigned long personality;
 189         int dumpable:1;
 190         int did_exec:1;
 191         int pid,pgrp,tty_old_pgrp,session,leader;
 192         int     groups[NGROUPS];
 193         /* 
 194          * pointers to (original) parent process, youngest child, younger sibling,
 195          * older sibling, respectively.  (p->father can be replaced with 
 196          * p->p_pptr->pid)
 197          */
 198         struct task_struct *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
 199         struct wait_queue *wait_chldexit;       /* for wait4() */
 200         unsigned short uid,euid,suid,fsuid;
 201         unsigned short gid,egid,sgid,fsgid;
 202         unsigned long timeout, policy, rt_priority;
 203         unsigned long it_real_value, it_prof_value, it_virt_value;
 204         unsigned long it_real_incr, it_prof_incr, it_virt_incr;
 205         struct timer_list real_timer;
 206         long utime, stime, cutime, cstime, start_time;
 207 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
 208         unsigned long min_flt, maj_flt, nswap, cmin_flt, cmaj_flt, cnswap;
 209         int swappable:1;
 210         unsigned long swap_address;
 211         unsigned long old_maj_flt;      /* old value of maj_flt */
 212         unsigned long dec_flt;          /* page fault count of the last time */
 213         unsigned long swap_cnt;         /* number of pages to swap on next pass */
 214 /* limits */
 215         struct rlimit rlim[RLIM_NLIMITS];
 216         unsigned short used_math;
 217         char comm[16];
 218 /* file system info */
 219         int link_count;
 220         struct tty_struct *tty; /* NULL if no tty */
 221 /* ipc stuff */
 222         struct sem_undo *semundo;
 223         struct sem_queue *semsleeping;
 224 /* ldt for this task - used by Wine.  If NULL, default_ldt is used */
 225         struct desc_struct *ldt;
 226 /* tss for this task */
 227         struct thread_struct tss;
 228 /* filesystem information */
 229         struct fs_struct *fs;
 230 /* open file information */
 231         struct files_struct *files;
 232 /* memory management info */
 233         struct mm_struct *mm;
 234 /* signal handlers */
 235         struct signal_struct *sig;
 236 #ifdef __SMP__
 237         int processor;
 238         int last_processor;
 239         int lock_depth;         /* Lock depth. We can context switch in and out of holding a syscall kernel lock... */  
 240 #endif  
 241 };
 242 
 243 /*
 244  * Per process flags
 245  */
 246 #define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
 247                                         /* Not implemented yet, only for 486*/
 248 #define PF_PTRACED      0x00000010      /* set if ptrace (0) has been called. */
 249 #define PF_TRACESYS     0x00000020      /* tracing system calls */
 250 
 251 #define PF_STARTING     0x00000100      /* being created */
 252 #define PF_EXITING      0x00000200      /* getting shut down */
 253 
 254 #define PF_USEDFPU      0x00100000      /* Process used the FPU this quantum (SMP only) */
 255 
 256 /*
 257  * Limit the stack by to some sane default: root can always
 258  * increase this limit if needed..  8MB seems reasonable.
 259  */
 260 #define _STK_LIM        (8*1024*1024)
 261 
 262 #define DEF_PRIORITY    (20*HZ/100)     /* 200 ms time slices */
 263 
 264 /*
 265  *  INIT_TASK is used to set up the first task table, touch at
 266  * your own risk!. Base=0, limit=0x1fffff (=2MB)
 267  */
 268 #define INIT_TASK \
 269 /* state etc */ { 0,DEF_PRIORITY,DEF_PRIORITY,0,0,0,0, \
 270 /* debugregs */ { 0, },            \
 271 /* exec domain */&default_exec_domain, \
 272 /* binfmt */    NULL, \
 273 /* schedlink */ &init_task,&init_task, &init_task, &init_task, \
 274 /* stack */     0,(unsigned long) &init_kernel_stack, \
 275 /* ec,brk... */ 0,0,0,0,0, \
 276 /* pid etc.. */ 0,0,0,0,0, \
 277 /* suppl grps*/ {NOGROUP,}, \
 278 /* proc links*/ &init_task,&init_task,NULL,NULL,NULL,NULL, \
 279 /* uid etc */   0,0,0,0,0,0,0,0, \
 280 /* timeout */   0,SCHED_OTHER,0,0,0,0,0,0,0, \
 281 /* timer */     { NULL, NULL, 0, 0, it_real_fn }, \
 282 /* utime */     0,0,0,0,0, \
 283 /* flt */       0,0,0,0,0,0, \
 284 /* swp */       0,0,0,0,0, \
 285 /* rlimits */   INIT_RLIMITS, \
 286 /* math */      0, \
 287 /* comm */      "swapper", \
 288 /* fs info */   0,NULL, \
 289 /* ipc */       NULL, NULL, \
 290 /* ldt */       NULL, \
 291 /* tss */       INIT_TSS, \
 292 /* fs */        &init_fs, \
 293 /* files */     &init_files, \
 294 /* mm */        &init_mm, \
 295 /* signals */   &init_signals, \
 296 }
 297 
 298 extern struct   mm_struct init_mm;
 299 extern struct task_struct init_task;
 300 extern struct task_struct *task[NR_TASKS];
 301 extern struct task_struct *last_task_used_math;
 302 extern struct task_struct *current_set[NR_CPUS];
 303 /*
 304  *      On a single processor system this comes out as current_set[0] when cpp
 305  *      has finished with it, which gcc will optimise away.
 306  */
 307 #define current (0+current_set[smp_processor_id()])     /* Current on this processor */
 308 extern unsigned long volatile jiffies;
 309 extern unsigned long itimer_ticks;
 310 extern unsigned long itimer_next;
 311 extern struct timeval xtime;
 312 extern int need_resched;
 313 extern void do_timer(struct pt_regs *);
 314 
 315 extern unsigned long * prof_buffer;
 316 extern unsigned long prof_len;
 317 extern unsigned long prof_shift;
 318 
 319 extern int securelevel; /* system security level */
 320 
 321 #define CURRENT_TIME (xtime.tv_sec)
 322 
 323 extern void sleep_on(struct wait_queue ** p);
 324 extern void interruptible_sleep_on(struct wait_queue ** p);
 325 extern void wake_up(struct wait_queue ** p);
 326 extern void wake_up_interruptible(struct wait_queue ** p);
 327 extern void wake_up_process(struct task_struct * tsk);
 328 
 329 extern void notify_parent(struct task_struct * tsk);
 330 extern int send_sig(unsigned long sig,struct task_struct * p,int priv);
 331 extern int in_group_p(gid_t grp);
 332 
 333 extern int request_irq(unsigned int irq,void (*handler)(int, struct pt_regs *),
 334         unsigned long flags, const char *device);
 335 extern void free_irq(unsigned int irq);
 336 
 337 extern void copy_thread(int, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
 338 extern void flush_thread(void);
 339 extern void exit_thread(void);
 340 
 341 extern void exit_fs(struct task_struct *);
 342 extern void exit_files(struct task_struct *);
 343 extern void exit_sighand(struct task_struct *);
 344 extern void release_thread(struct task_struct *);
 345 
 346 extern int do_execve(char *, char **, char **, struct pt_regs *);
 347 extern int do_fork(unsigned long, unsigned long, struct pt_regs *);
 348 
 349 /*
 350  * The wait-queues are circular lists, and you have to be *very* sure
 351  * to keep them correct. Use only these two functions to add/remove
 352  * entries in the queues.
 353  */
 354 extern inline void add_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 355 {
 356         unsigned long flags;
 357 
 358 #ifdef DEBUG
 359         if (wait->next) {
 360                 __label__ here;
 361                 unsigned long pc;
 362                 pc = (unsigned long) &&here;
 363               here:
 364                 printk("add_wait_queue (%08lx): wait->next = %08lx\n",pc,(unsigned long) wait->next);
 365         }
 366 #endif
 367         save_flags(flags);
 368         cli();
 369         if (!*p) {
 370                 wait->next = wait;
 371                 *p = wait;
 372         } else {
 373                 wait->next = (*p)->next;
 374                 (*p)->next = wait;
 375         }
 376         restore_flags(flags);
 377 }
 378 
 379 extern inline void remove_wait_queue(struct wait_queue ** p, struct wait_queue * wait)
     /*  */
 380 {
 381         unsigned long flags;
 382         struct wait_queue * tmp;
 383 #ifdef DEBUG
 384         unsigned long ok = 0;
 385 #endif
 386 
 387         save_flags(flags);
 388         cli();
 389         if ((*p == wait) &&
 390 #ifdef DEBUG
 391             (ok = 1) &&
 392 #endif
 393             ((*p = wait->next) == wait)) {
 394                 *p = NULL;
 395         } else {
 396                 tmp = wait;
 397                 while (tmp->next != wait) {
 398                         tmp = tmp->next;
 399 #ifdef DEBUG
 400                         if (tmp == *p)
 401                                 ok = 1;
 402 #endif
 403                 }
 404                 tmp->next = wait->next;
 405         }
 406         wait->next = NULL;
 407         restore_flags(flags);
 408 #ifdef DEBUG
 409         if (!ok) {
 410                 __label__ here;
 411                 ok = (unsigned long) &&here;
 412                 printk("removed wait_queue not on list.\n");
 413                 printk("list = %08lx, queue = %08lx\n",(unsigned long) p, (unsigned long) wait);
 414               here:
 415                 printk("eip = %08lx\n",ok);
 416         }
 417 #endif
 418 }
 419 
 420 extern inline void select_wait(struct wait_queue ** wait_address, select_table * p)
     /*  */
 421 {
 422         struct select_table_entry * entry;
 423 
 424         if (!p || !wait_address)
 425                 return;
 426         if (p->nr >= __MAX_SELECT_TABLE_ENTRIES)
 427                 return;
 428         entry = p->entry + p->nr;
 429         entry->wait_address = wait_address;
 430         entry->wait.task = current;
 431         entry->wait.next = NULL;
 432         add_wait_queue(wait_address,&entry->wait);
 433         p->nr++;
 434 }
 435 
 436 extern void __down(struct semaphore * sem);
 437 
 438 /*
 439  * These are not yet interrupt-safe
 440  */
 441 extern inline void down(struct semaphore * sem)
     /*  */
 442 {
 443         if (sem->count <= 0)
 444                 __down(sem);
 445         sem->count--;
 446 }
 447 
 448 extern inline void up(struct semaphore * sem)
     /*  */
 449 {
 450         sem->count++;
 451         wake_up(&sem->wait);
 452 }       
 453 
 454 #define REMOVE_LINKS(p) do { unsigned long flags; \
 455         save_flags(flags) ; cli(); \
 456         (p)->next_task->prev_task = (p)->prev_task; \
 457         (p)->prev_task->next_task = (p)->next_task; \
 458         restore_flags(flags); \
 459         if ((p)->p_osptr) \
 460                 (p)->p_osptr->p_ysptr = (p)->p_ysptr; \
 461         if ((p)->p_ysptr) \
 462                 (p)->p_ysptr->p_osptr = (p)->p_osptr; \
 463         else \
 464                 (p)->p_pptr->p_cptr = (p)->p_osptr; \
 465         } while (0)
 466 
 467 #define SET_LINKS(p) do { unsigned long flags; \
 468         save_flags(flags); cli(); \
 469         (p)->next_task = &init_task; \
 470         (p)->prev_task = init_task.prev_task; \
 471         init_task.prev_task->next_task = (p); \
 472         init_task.prev_task = (p); \
 473         restore_flags(flags); \
 474         (p)->p_ysptr = NULL; \
 475         if (((p)->p_osptr = (p)->p_pptr->p_cptr) != NULL) \
 476                 (p)->p_osptr->p_ysptr = p; \
 477         (p)->p_pptr->p_cptr = p; \
 478         } while (0)
 479 
 480 #define for_each_task(p) \
 481         for (p = &init_task ; (p = p->next_task) != &init_task ; )
 482 
 483 #endif /* __KERNEL__ */
 484 
 485 #endif
/* */
root/include/linux/sched.h

INCLUDED FROM

DEFINITIONS
