linuxthreads/internals.h

   1 /* Linuxthreads - a simple clone()-based implementation of Posix        */
   2 /* threads for Linux.                                                   */
   3 /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */
   4 /*                                                                      */
   5 /* This program is free software; you can redistribute it and/or        */
   6 /* modify it under the terms of the GNU Library General Public License  */
   7 /* as published by the Free Software Foundation; either version 2       */
   8 /* of the License, or (at your option) any later version.               */
   9 /*                                                                      */
  10 /* This program is distributed in the hope that it will be useful,      */
  11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of       */
  12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        */
  13 /* GNU Library General Public License for more details.                 */
  14
  15 #ifndef _INTERNALS_H
  16 #define _INTERNALS_H    1
  17
  18 /* Internal data structures */
  19
  20 /* Includes */
  21
  22 #include <limits.h>
  23 #include <signal.h>
  24 #include <unistd.h>
  25 #include <stackinfo.h>
  26 #include <sigcontextinfo.h>
  27
  28 #include <tls.h>
  29 #include "descr.h"
  30
  31 #include "semaphore.h"
  32
  33 #ifndef THREAD_GETMEM
  34 # define THREAD_GETMEM(descr, member) descr->member
  35 #endif
  36 #ifndef THREAD_GETMEM_NC
  37 # define THREAD_GETMEM_NC(descr, member) descr->member
  38 #endif
  39 #ifndef THREAD_SETMEM
  40 # define THREAD_SETMEM(descr, member, value) descr->member = (value)
  41 #endif
  42 #ifndef THREAD_SETMEM_NC
  43 # define THREAD_SETMEM_NC(descr, member, value) descr->member = (value)
  44 #endif
  45
  46 typedef void (*destr_function)(void *);
  47
  48 struct pthread_key_struct {
  49   int in_use;                   /* already allocated? */
  50   destr_function destr;         /* destruction routine */
  51 };
  52
  53
  54 #define PTHREAD_START_ARGS_INITIALIZER(fct) \
  55   { (void *(*) (void *)) fct, NULL, {{0, }}, 0, { 0 } }
  56
  57
  58 /* The type of thread handles. */
  59
  60 typedef struct pthread_handle_struct * pthread_handle;
  61
  62 struct pthread_handle_struct {
  63   struct _pthread_fastlock h_lock; /* Fast lock for sychronized access */
  64   pthread_descr h_descr;        /* Thread descriptor or NULL if invalid */
  65   char * h_bottom;              /* Lowest address in the stack thread */
  66 };
  67
  68 /* The type of messages sent to the thread manager thread */
  69
  70 struct pthread_request {
  71   pthread_descr req_thread;     /* Thread doing the request */
  72   enum {                        /* Request kind */
  73     REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT,
  74     REQ_POST, REQ_DEBUG, REQ_KICK, REQ_FOR_EACH_THREAD
  75   } req_kind;
  76   union {                       /* Arguments for request */
  77     struct {                    /* For REQ_CREATE: */
  78       const pthread_attr_t * attr; /* thread attributes */
  79       void * (*fn)(void *);     /*   start function */
  80       void * arg;               /*   argument to start function */
  81       sigset_t mask;            /*   signal mask */
  82     } create;
  83     struct {                    /* For REQ_FREE: */
  84       pthread_t thread_id;      /*   identifier of thread to free */
  85     } free;
  86     struct {                    /* For REQ_PROCESS_EXIT: */
  87       int code;                 /*   exit status */
  88     } exit;
  89     void * post;                /* For REQ_POST: the semaphore */
  90     struct {                    /* For REQ_FOR_EACH_THREAD: callback */
  91       void (*fn)(void *, pthread_descr);
  92       void *arg;
  93     } for_each;
  94   } req_args;
  95 };
  96
  97
  98
  99 typedef void (*arch_sighandler_t) (int, SIGCONTEXT);
 100 union sighandler
 101 {
 102   arch_sighandler_t old;
 103   void (*rt) (int, struct siginfo *, struct ucontext *);
 104 };
 105 extern union sighandler __sighandler[NSIG];
 106
 107
 108 /* Signals used for suspend/restart and for cancellation notification.  */
 109
 110 extern int __pthread_sig_restart;
 111 extern int __pthread_sig_cancel;
 112
 113 /* Signal used for interfacing with gdb */
 114
 115 extern int __pthread_sig_debug;
 116
 117 /* Global array of thread handles, used for validating a thread id
 118    and retrieving the corresponding thread descriptor. Also used for
 119    mapping the available stack segments. */
 120
 121 extern struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX];
 122
 123 /* Descriptor of the main thread */
 124
 125 extern pthread_descr __pthread_main_thread;
 126
 127 /* File descriptor for sending requests to the thread manager.
 128    Initially -1, meaning that __pthread_initialize_manager must be called. */
 129
 130 extern int __pthread_manager_request;
 131
 132 /* Other end of the pipe for sending requests to the thread manager. */
 133
 134 extern int __pthread_manager_reader;
 135
 136 #ifdef FLOATING_STACKS
 137 /* Maximum stack size.  */
 138 extern size_t __pthread_max_stacksize;
 139 #endif
 140
 141 /* Pending request for a process-wide exit */
 142
 143 extern int __pthread_exit_requested, __pthread_exit_code;
 144
 145 /* Set to 1 by gdb if we're debugging */
 146
 147 extern volatile int __pthread_threads_debug;
 148
 149 /* Globally enabled events.  */
 150 extern volatile td_thr_events_t __pthread_threads_events;
 151
 152 /* Pointer to descriptor of thread with last event.  */
 153 extern volatile pthread_descr __pthread_last_event;
 154
 155 /* Flag which tells whether we are executing on SMP kernel. */
 156 extern int __pthread_smp_kernel;
 157
 158 /* Return the handle corresponding to a thread id */
 159
 160 static inline pthread_handle thread_handle(pthread_t id)
 161 {
 162   return &__pthread_handles[id % PTHREAD_THREADS_MAX];
 163 }
 164
 165 /* Validate a thread handle. Must have acquired h->h_spinlock before. */
 166
 167 static inline int invalid_handle(pthread_handle h, pthread_t id)
 168 {
 169   return h->h_descr == NULL || h->h_descr->p_tid != id || h->h_descr->p_terminated;
 170 }
 171
 172 static inline int nonexisting_handle(pthread_handle h, pthread_t id)
 173 {
 174   return h->h_descr == NULL || h->h_descr->p_tid != id;
 175 }
 176
 177 /* Fill in defaults left unspecified by pt-machine.h.  */
 178
 179 /* We round up a value with page size. */
 180 #ifndef page_roundup
 181 #define page_roundup(v,p) ((((size_t) (v)) + (p) - 1) & ~((p) - 1))
 182 #endif
 183
 184 /* The page size we can get from the system.  This should likely not be
 185    changed by the machine file but, you never know.  */
 186 #ifndef PAGE_SIZE
 187 #define PAGE_SIZE  (sysconf (_SC_PAGE_SIZE))
 188 #endif
 189
 190 /* The initial size of the thread stack.  Must be a multiple of PAGE_SIZE.  */
 191 #ifndef INITIAL_STACK_SIZE
 192 #define INITIAL_STACK_SIZE  (4 * PAGE_SIZE)
 193 #endif
 194
 195 /* Size of the thread manager stack. The "- 32" avoids wasting space
 196    with some malloc() implementations. */
 197 #ifndef THREAD_MANAGER_STACK_SIZE
 198 #define THREAD_MANAGER_STACK_SIZE  (2 * PAGE_SIZE - 32)
 199 #endif
 200
 201 /* The base of the "array" of thread stacks.  The array will grow down from
 202    here.  Defaults to the calculated bottom of the initial application
 203    stack.  */
 204 #ifndef THREAD_STACK_START_ADDRESS
 205 #define THREAD_STACK_START_ADDRESS  __pthread_initial_thread_bos
 206 #endif
 207
 208 /* If MEMORY_BARRIER isn't defined in pt-machine.h, assume the
 209    architecture doesn't need a memory barrier instruction (e.g. Intel
 210    x86).  Still we need the compiler to respect the barrier and emit
 211    all outstanding operations which modify memory.  Some architectures
 212    distinguish between full, read and write barriers.  */
 213
 214 #ifndef MEMORY_BARRIER
 215 #define MEMORY_BARRIER() asm ("" : : : "memory")
 216 #endif
 217 #ifndef READ_MEMORY_BARRIER
 218 #define READ_MEMORY_BARRIER() MEMORY_BARRIER()
 219 #endif
 220 #ifndef WRITE_MEMORY_BARRIER
 221 #define WRITE_MEMORY_BARRIER() MEMORY_BARRIER()
 222 #endif
 223
 224 /* Max number of times we must spin on a spinlock calling sched_yield().
 225    After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */
 226
 227 #ifndef MAX_SPIN_COUNT
 228 #define MAX_SPIN_COUNT 50
 229 #endif
 230
 231 /* Max number of times the spinlock in the adaptive mutex implementation
 232    spins actively on SMP systems.  */
 233
 234 #ifndef MAX_ADAPTIVE_SPIN_COUNT
 235 #define MAX_ADAPTIVE_SPIN_COUNT 100
 236 #endif
 237
 238 /* Duration of sleep (in nanoseconds) when we can't acquire a spinlock
 239    after MAX_SPIN_COUNT iterations of sched_yield().
 240    With the 2.0 and 2.1 kernels, this MUST BE > 2ms.
 241    (Otherwise the kernel does busy-waiting for realtime threads,
 242     giving other threads no chance to run.) */
 243
 244 #ifndef SPIN_SLEEP_DURATION
 245 #define SPIN_SLEEP_DURATION 2000001
 246 #endif
 247
 248 /* Debugging */
 249
 250 #ifdef DEBUG
 251 #include <assert.h>
 252 #define ASSERT assert
 253 #define MSG __pthread_message
 254 #else
 255 #define ASSERT(x)
 256 #define MSG(msg,arg...)
 257 #endif
 258
 259 /* Internal global functions */
 260
 261 extern void __pthread_do_exit (void *retval, char *currentframe)
 262      __attribute__ ((__noreturn__));
 263 extern void __pthread_destroy_specifics (void);
 264 extern void __pthread_perform_cleanup (char *currentframe);
 265 extern void __pthread_init_max_stacksize (void);
 266 extern int __pthread_initialize_manager (void);
 267 extern void __pthread_message (char * fmt, ...);
 268 extern int __pthread_manager (void *reqfd);
 269 extern int __pthread_manager_event (void *reqfd);
 270 extern void __pthread_manager_sighandler (int sig);
 271 extern void __pthread_reset_main_thread (void);
 272 extern void __pthread_once_fork_prepare (void);
 273 extern void __pthread_once_fork_parent (void);
 274 extern void __pthread_once_fork_child (void);
 275 extern void __flockfilelist (void);
 276 extern void __funlockfilelist (void);
 277 extern void __fresetlockfiles (void);
 278 extern void __pthread_manager_adjust_prio (int thread_prio);
 279 extern void __pthread_initialize_minimal (void);
 280
 281 extern int __pthread_attr_setguardsize (pthread_attr_t *__attr,
 282                                         size_t __guardsize);
 283 extern int __pthread_attr_getguardsize (const pthread_attr_t *__attr,
 284                                         size_t *__guardsize);
 285 extern int __pthread_attr_setstackaddr (pthread_attr_t *__attr,
 286                                         void *__stackaddr);
 287 extern int __pthread_attr_getstackaddr (const pthread_attr_t *__attr,
 288                                         void **__stackaddr);
 289 extern int __pthread_attr_setstacksize (pthread_attr_t *__attr,
 290                                         size_t __stacksize);
 291 extern int __pthread_attr_getstacksize (const pthread_attr_t *__attr,
 292                                         size_t *__stacksize);
 293 extern int __pthread_attr_setstack (pthread_attr_t *__attr, void *__stackaddr,
 294                                     size_t __stacksize);
 295 extern int __pthread_attr_getstack (const pthread_attr_t *__attr, void **__stackaddr,
 296                                     size_t *__stacksize);
 297 extern int __pthread_getconcurrency (void);
 298 extern int __pthread_setconcurrency (int __level);
 299 extern int __pthread_mutex_timedlock (pthread_mutex_t *__mutex,
 300                                       const struct timespec *__abstime);
 301 extern int __pthread_mutexattr_getpshared (const pthread_mutexattr_t *__attr,
 302                                            int *__pshared);
 303 extern int __pthread_mutexattr_setpshared (pthread_mutexattr_t *__attr,
 304                                            int __pshared);
 305 extern int __pthread_mutexattr_gettype (const pthread_mutexattr_t *__attr,
 306                                         int *__kind);
 307 extern void __pthread_kill_other_threads_np (void);
 308
 309 extern void __pthread_restart_old(pthread_descr th);
 310 extern void __pthread_suspend_old(pthread_descr self);
 311 extern int __pthread_timedsuspend_old(pthread_descr self, const struct timespec *abs);
 312
 313 extern void __pthread_restart_new(pthread_descr th);
 314 extern void __pthread_suspend_new(pthread_descr self);
 315 extern int __pthread_timedsuspend_new(pthread_descr self, const struct timespec *abs);
 316
 317 extern void __pthread_wait_for_restart_signal(pthread_descr self);
 318
 319 extern int __pthread_yield (void);
 320
 321 extern int __pthread_rwlock_timedrdlock (pthread_rwlock_t *__restrict __rwlock,
 322                                          __const struct timespec *__restrict
 323                                          __abstime);
 324 extern int __pthread_rwlock_timedwrlock (pthread_rwlock_t *__restrict __rwlock,
 325                                          __const struct timespec *__restrict
 326                                          __abstime);
 327 extern int __pthread_rwlockattr_destroy (pthread_rwlockattr_t *__attr);
 328
 329 extern int __pthread_barrierattr_getpshared (__const pthread_barrierattr_t *
 330                                              __restrict __attr,
 331                                              int *__restrict __pshared);
 332
 333 extern int __pthread_spin_lock (pthread_spinlock_t *__lock);
 334 extern int __pthread_spin_trylock (pthread_spinlock_t *__lock);
 335 extern int __pthread_spin_unlock (pthread_spinlock_t *__lock);
 336 extern int __pthread_spin_init (pthread_spinlock_t *__lock, int __pshared);
 337 extern int __pthread_spin_destroy (pthread_spinlock_t *__lock);
 338
 339 extern int __pthread_clock_gettime (hp_timing_t freq, struct timespec *tp);
 340 extern void __pthread_clock_settime (hp_timing_t offset);
 341
 342
 343 /* Global pointers to old or new suspend functions */
 344
 345 extern void (*__pthread_restart)(pthread_descr);
 346 extern void (*__pthread_suspend)(pthread_descr);
 347 extern int (*__pthread_timedsuspend)(pthread_descr, const struct timespec *);
 348
 349 /* Prototypes for the function without cancelation support when the
 350    normal version has it.  */
 351 extern int __libc_close (int fd);
 352 extern int __libc_nanosleep (const struct timespec *requested_time,
 353                              struct timespec *remaining);
 354 /* Prototypes for some of the new semaphore functions.  */
 355 extern int __new_sem_post (sem_t * sem);
 356 extern int __new_sem_init (sem_t *__sem, int __pshared, unsigned int __value);
 357 extern int __new_sem_wait (sem_t *__sem);
 358 extern int __new_sem_trywait (sem_t *__sem);
 359 extern int __new_sem_getvalue (sem_t *__restrict __sem, int *__restrict __sval);
 360 extern int __new_sem_destroy (sem_t *__sem);
 361
 362 /* Prototypes for compatibility functions.  */
 363 extern int __pthread_attr_init_2_1 (pthread_attr_t *__attr);
 364 extern int __pthread_attr_init_2_0 (pthread_attr_t *__attr);
 365 extern int __pthread_create_2_1 (pthread_t *__restrict __threadp,
 366                                  const pthread_attr_t *__attr,
 367                                  void *(*__start_routine) (void *),
 368                                  void *__restrict __arg);
 369 extern int __pthread_create_2_0 (pthread_t *__restrict thread,
 370                                  const pthread_attr_t *__attr,
 371                                  void *(*__start_routine) (void *),
 372                                  void *__restrict arg);
 373
 374 /* The functions called the signal events.  */
 375 extern void __linuxthreads_create_event (void);
 376 extern void __linuxthreads_death_event (void);
 377 extern void __linuxthreads_reap_event (void);
 378
 379 /* This function is called to initialize the pthread library.  */
 380 extern void __pthread_initialize (void);
 381
 382
 383 /* Sighandler wrappers.  */
 384 extern void __pthread_sighandler(int signo, SIGCONTEXT ctx);
 385 extern void __pthread_sighandler_rt(int signo, struct siginfo *si,
 386                                     struct ucontext *uc);
 387 extern void __pthread_null_sighandler(int sig);
 388
 389 #endif /* internals.h */