1 /* Linuxthreads - a simple clone()-based implementation of Posix */
2 /* threads for Linux. */
3 /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
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. */
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. */
16 #define _INTERNALS_H 1
18 /* Internal data structures */
22 #include <bits/libc-tsd.h> /* for _LIBC_TSD_KEY_N */
27 #include <bits/stackinfo.h>
28 #include <sys/types.h>
30 #include "pt-machine.h"
31 #include "semaphore.h"
32 #include "../linuxthreads.old_db/thread_dbP.h"
33 #ifdef __UCLIBC_HAS_XLOCALE__
34 #include <bits/uClibc_locale.h>
35 #endif /* __UCLIBC_HAS_XLOCALE__ */
37 /* Use a funky version in a probably vein attempt at preventing gdb
38 * from dlopen()'ing glibc's libthread_db library... */
39 #define VERSION __stringify(__UCLIBC_MAJOR__) "." __stringify(__UCLIBC_MINOR__) "." __stringify(__UCLIBC_SUBLEVEL__)
42 # define THREAD_GETMEM(descr, member) descr->member
44 #ifndef THREAD_GETMEM_NC
45 # define THREAD_GETMEM_NC(descr, member) descr->member
48 # define THREAD_SETMEM(descr, member, value) descr->member = (value)
50 #ifndef THREAD_SETMEM_NC
51 # define THREAD_SETMEM_NC(descr, member, value) descr->member = (value)
54 /* Arguments passed to thread creation routine */
56 struct pthread_start_args {
57 void * (*start_routine)(void *); /* function to run */
58 void * arg; /* its argument */
59 sigset_t mask; /* initial signal mask for thread */
60 int schedpolicy; /* initial scheduling policy (if any) */
61 struct sched_param schedparam; /* initial scheduling parameters (if any) */
65 /* We keep thread specific data in a special data structure, a two-level
66 array. The top-level array contains pointers to dynamically allocated
67 arrays of a certain number of data pointers. So we can implement a
68 sparse array. Each dynamic second-level array has
69 PTHREAD_KEY_2NDLEVEL_SIZE
70 entries. This value shouldn't be too large. */
71 #define PTHREAD_KEY_2NDLEVEL_SIZE 32
73 /* We need to address PTHREAD_KEYS_MAX key with PTHREAD_KEY_2NDLEVEL_SIZE
74 keys in each subarray. */
75 #define PTHREAD_KEY_1STLEVEL_SIZE \
76 ((PTHREAD_KEYS_MAX + PTHREAD_KEY_2NDLEVEL_SIZE - 1) \
77 / PTHREAD_KEY_2NDLEVEL_SIZE)
79 typedef void (*destr_function)(void *);
81 struct pthread_key_struct {
82 int in_use; /* already allocated? */
83 destr_function destr; /* destruction routine */
87 #define PTHREAD_START_ARGS_INITIALIZER { NULL, NULL, {{0, }}, 0, { 0 } }
89 /* The type of thread descriptors */
91 typedef struct _pthread_descr_struct * pthread_descr;
93 /* Callback interface for removing the thread from waiting on an
94 object if it is cancelled while waiting or about to wait.
95 This hold a pointer to the object, and a pointer to a function
96 which ``extricates'' the thread from its enqueued state.
97 The function takes two arguments: pointer to the wait object,
98 and a pointer to the thread. It returns 1 if an extrication
99 actually occured, and hence the thread must also be signalled.
100 It returns 0 if the thread had already been extricated. */
102 typedef struct _pthread_extricate_struct {
104 int (*pu_extricate_func)(void *, pthread_descr);
105 } pthread_extricate_if;
107 /* Atomic counter made possible by compare_and_swap */
109 struct pthread_atomic {
114 /* Context info for read write locks. The pthread_rwlock_info structure
115 is information about a lock that has been read-locked by the thread
116 in whose list this structure appears. The pthread_rwlock_context
117 is embedded in the thread context and contains a pointer to the
118 head of the list of lock info structures, as well as a count of
119 read locks that are untracked, because no info structure could be
120 allocated for them. */
122 struct _pthread_rwlock_t;
124 typedef struct _pthread_rwlock_info {
125 struct _pthread_rwlock_info *pr_next;
126 struct _pthread_rwlock_t *pr_lock;
128 } pthread_readlock_info;
130 struct _pthread_descr_struct {
131 pthread_descr p_nextlive, p_prevlive;
132 /* Double chaining of active threads */
133 pthread_descr p_nextwaiting; /* Next element in the queue holding the thr */
134 pthread_descr p_nextlock; /* can be on a queue and waiting on a lock */
135 pthread_t p_tid; /* Thread identifier */
136 int p_pid; /* PID of Unix process */
137 int p_priority; /* Thread priority (== 0 if not realtime) */
138 struct _pthread_fastlock * p_lock; /* Spinlock for synchronized accesses */
139 int p_signal; /* last signal received */
140 sigjmp_buf * p_signal_jmp; /* where to siglongjmp on a signal or NULL */
141 sigjmp_buf * p_cancel_jmp; /* where to siglongjmp on a cancel or NULL */
142 char p_terminated; /* true if terminated e.g. by pthread_exit */
143 char p_detached; /* true if detached */
144 char p_exited; /* true if the assoc. process terminated */
145 void * p_retval; /* placeholder for return value */
146 int p_retcode; /* placeholder for return code */
147 pthread_descr p_joining; /* thread joining on that thread or NULL */
148 struct _pthread_cleanup_buffer * p_cleanup; /* cleanup functions */
149 char p_cancelstate; /* cancellation state */
150 char p_canceltype; /* cancellation type (deferred/async) */
151 char p_canceled; /* cancellation request pending */
152 int * p_errnop; /* pointer to used errno variable */
153 int p_errno; /* error returned by last system call */
154 int * p_h_errnop; /* pointer to used h_errno variable */
155 int p_h_errno; /* error returned by last netdb function */
156 char * p_in_sighandler; /* stack address of sighandler, or NULL */
157 char p_sigwaiting; /* true if a sigwait() is in progress */
158 struct pthread_start_args p_start_args; /* arguments for thread creation */
159 void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE]; /* thread-specific data */
160 void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */
161 int p_userstack; /* nonzero if the user provided the stack */
162 void *p_guardaddr; /* address of guard area or NULL */
163 size_t p_guardsize; /* size of guard area */
164 pthread_descr p_self; /* Pointer to this structure */
165 int p_nr; /* Index of descriptor in __pthread_handles */
166 int p_report_events; /* Nonzero if events must be reported. */
167 td_eventbuf_t p_eventbuf; /* Data for event. */
168 struct pthread_atomic p_resume_count; /* number of times restart() was
170 char p_woken_by_cancel; /* cancellation performed wakeup */
171 char p_condvar_avail; /* flag if conditional variable became avail */
172 char p_sem_avail; /* flag if semaphore became available */
173 pthread_extricate_if *p_extricate; /* See above */
174 pthread_readlock_info *p_readlock_list; /* List of readlock info structs */
175 pthread_readlock_info *p_readlock_free; /* Free list of structs */
176 int p_untracked_readlock_count; /* Readlocks not tracked by list */
177 /* New elements must be added at the end. */
178 #ifdef __UCLIBC_HAS_XLOCALE__
179 __locale_t locale; /* thread-specific locale from uselocale() only! */
180 #endif /* __UCLIBC_HAS_XLOCALE__ */
181 } __attribute__ ((aligned(32))); /* We need to align the structure so that
182 doubles are aligned properly. This is 8
183 bytes on MIPS and 16 bytes on MIPS64.
184 32 bytes might give better cache
187 /* The type of thread handles. */
189 typedef struct pthread_handle_struct * pthread_handle;
191 struct pthread_handle_struct {
192 struct _pthread_fastlock h_lock; /* Fast lock for sychronized access */
193 pthread_descr h_descr; /* Thread descriptor or NULL if invalid */
194 char * h_bottom; /* Lowest address in the stack thread */
197 /* The type of messages sent to the thread manager thread */
199 struct pthread_request {
200 pthread_descr req_thread; /* Thread doing the request */
201 enum { /* Request kind */
202 REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT,
203 REQ_POST, REQ_DEBUG, REQ_KICK
205 union { /* Arguments for request */
206 struct { /* For REQ_CREATE: */
207 const pthread_attr_t * attr; /* thread attributes */
208 void * (*fn)(void *); /* start function */
209 void * arg; /* argument to start function */
210 sigset_t mask; /* signal mask */
212 struct { /* For REQ_FREE: */
213 pthread_t thread_id; /* identifier of thread to free */
215 struct { /* For REQ_PROCESS_EXIT: */
216 int code; /* exit status */
218 void * post; /* For REQ_POST: the semaphore */
223 /* Signals used for suspend/restart and for cancellation notification. */
225 extern int __pthread_sig_restart;
226 extern int __pthread_sig_cancel;
228 /* Signal used for interfacing with gdb */
230 extern int __pthread_sig_debug;
232 /* Global array of thread handles, used for validating a thread id
233 and retrieving the corresponding thread descriptor. Also used for
234 mapping the available stack segments. */
236 extern struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX];
238 /* Descriptor of the initial thread */
240 extern struct _pthread_descr_struct __pthread_initial_thread;
242 /* Descriptor of the manager thread */
244 extern struct _pthread_descr_struct __pthread_manager_thread;
246 /* Descriptor of the main thread */
248 extern pthread_descr __pthread_main_thread;
250 /* Limit between the stack of the initial thread (above) and the
251 stacks of other threads (below). Aligned on a STACK_SIZE boundary.
252 Initially 0, meaning that the current thread is (by definition)
253 the initial thread. */
255 /* For non-MMU systems also remember to stack top of the initial thread.
256 * This is adapted when other stacks are malloc'ed since we don't know
257 * the bounds a-priori. -StS */
259 extern char *__pthread_initial_thread_bos;
260 #ifndef __ARCH_USE_MMU__
261 extern char *__pthread_initial_thread_tos;
262 #define NOMMU_INITIAL_THREAD_BOUNDS(tos,bos) \
263 if ((tos)>=__pthread_initial_thread_bos \
264 && (bos)<__pthread_initial_thread_tos) \
265 __pthread_initial_thread_bos = (tos)+1
267 #define NOMMU_INITIAL_THREAD_BOUNDS(tos,bos) /* empty */
268 #endif /* __ARCH_USE_MMU__ */
271 /* Indicate whether at least one thread has a user-defined stack (if 1),
272 or all threads have stacks supplied by LinuxThreads (if 0). */
274 extern int __pthread_nonstandard_stacks;
276 /* File descriptor for sending requests to the thread manager.
277 Initially -1, meaning that __pthread_initialize_manager must be called. */
279 extern int __pthread_manager_request;
281 /* Other end of the pipe for sending requests to the thread manager. */
283 extern int __pthread_manager_reader;
285 /* Limits of the thread manager stack. */
287 extern char *__pthread_manager_thread_bos;
288 extern char *__pthread_manager_thread_tos;
290 /* Pending request for a process-wide exit */
292 extern int __pthread_exit_requested, __pthread_exit_code;
294 /* Set to 1 by gdb if we're debugging */
296 extern volatile int __pthread_threads_debug;
298 /* Globally enabled events. */
299 extern volatile td_thr_events_t __pthread_threads_events;
301 /* Pointer to descriptor of thread with last event. */
302 extern volatile pthread_descr __pthread_last_event;
304 /* Return the handle corresponding to a thread id */
306 static __inline__ pthread_handle thread_handle(pthread_t id)
308 return &__pthread_handles[id % PTHREAD_THREADS_MAX];
311 /* Validate a thread handle. Must have acquired h->h_spinlock before. */
313 static __inline__ int invalid_handle(pthread_handle h, pthread_t id)
315 return h->h_descr == NULL || h->h_descr->p_tid != id;
318 /* Fill in defaults left unspecified by pt-machine.h. */
320 /* The page size we can get from the system. This should likely not be
321 changed by the machine file but, you never know. */
322 extern size_t __pagesize;
323 #include <bits/uClibc_page.h>
325 #define PAGE_SIZE (sysconf (_SC_PAGESIZE))
328 /* The max size of the thread stack segments. If the default
329 THREAD_SELF implementation is used, this must be a power of two and
330 a multiple of PAGE_SIZE. */
332 #ifdef __ARCH_USE_MMU__
333 #define STACK_SIZE (2 * 1024 * 1024)
335 #define STACK_SIZE (4 * __pagesize)
339 /* The initial size of the thread stack. Must be a multiple of PAGE_SIZE. */
340 #ifndef INITIAL_STACK_SIZE
341 #define INITIAL_STACK_SIZE (4 * __pagesize)
344 /* Size of the thread manager stack. The "- 32" avoids wasting space
345 with some malloc() implementations. */
346 #ifndef THREAD_MANAGER_STACK_SIZE
347 #define THREAD_MANAGER_STACK_SIZE (2 * __pagesize - 32)
350 /* The base of the "array" of thread stacks. The array will grow down from
351 here. Defaults to the calculated bottom of the initial application
353 #ifndef THREAD_STACK_START_ADDRESS
354 #define THREAD_STACK_START_ADDRESS __pthread_initial_thread_bos
357 /* Get some notion of the current stack. Need not be exactly the top
358 of the stack, just something somewhere in the current frame. */
359 #ifndef CURRENT_STACK_FRAME
360 #define CURRENT_STACK_FRAME ({ char __csf; &__csf; })
363 /* If MEMORY_BARRIER isn't defined in pt-machine.h, assume the
364 architecture doesn't need a memory barrier instruction (e.g. Intel
365 x86). Still we need the compiler to respect the barrier and emit
366 all outstanding operations which modify memory. Some architectures
367 distinguish between full, read and write barriers. */
368 #ifndef MEMORY_BARRIER
369 #define MEMORY_BARRIER() __asm__ ("" : : : "memory")
371 #ifndef READ_MEMORY_BARRIER
372 #define READ_MEMORY_BARRIER() MEMORY_BARRIER()
374 #ifndef WRITE_MEMORY_BARRIER
375 #define WRITE_MEMORY_BARRIER() MEMORY_BARRIER()
378 /* Recover thread descriptor for the current thread */
380 extern pthread_descr __pthread_find_self (void) __attribute__ ((const));
382 static __inline__ pthread_descr thread_self (void) __attribute__ ((const));
383 static __inline__ pthread_descr thread_self (void)
388 char *sp = CURRENT_STACK_FRAME;
389 #ifdef __ARCH_USE_MMU__
390 if (sp >= __pthread_initial_thread_bos)
391 return &__pthread_initial_thread;
392 else if (sp >= __pthread_manager_thread_bos
393 && sp < __pthread_manager_thread_tos)
394 return &__pthread_manager_thread;
395 else if (__pthread_nonstandard_stacks)
396 return __pthread_find_self();
398 return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1;
400 /* For non-MMU we need to be more careful about the initial thread stack.
401 * We refine the initial thread stack bounds dynamically as we allocate
402 * the other stack frame such that it doesn't overlap with them. Then
403 * we can be sure to pick the right thread according to the current SP */
405 /* Since we allow other stack frames to be above or below, we need to
406 * treat this case special. When pthread_initialize() wasn't called yet,
407 * only the initial thread is there. */
408 if (__pthread_initial_thread_bos == NULL) {
409 return &__pthread_initial_thread;
411 else if (sp >= __pthread_initial_thread_bos
412 && sp < __pthread_initial_thread_tos) {
413 return &__pthread_initial_thread;
415 else if (sp >= __pthread_manager_thread_bos
416 && sp < __pthread_manager_thread_tos) {
417 return &__pthread_manager_thread;
420 return __pthread_find_self();
422 #endif /* __ARCH_USE_MMU__ */
426 /* Max number of times we must spin on a spinlock calling sched_yield().
427 After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */
429 #ifndef MAX_SPIN_COUNT
430 #define MAX_SPIN_COUNT 50
433 /* Duration of sleep (in nanoseconds) when we can't acquire a spinlock
434 after MAX_SPIN_COUNT iterations of sched_yield().
435 With the 2.0 and 2.1 kernels, this MUST BE > 2ms.
436 (Otherwise the kernel does busy-waiting for realtime threads,
437 giving other threads no chance to run.) */
439 #ifndef SPIN_SLEEP_DURATION
440 #define SPIN_SLEEP_DURATION 2000001
443 /* Defined and used in libc.so. */
444 extern int __libc_multiple_threads attribute_hidden;
445 extern int __librt_multiple_threads;
447 /* Internal global functions */
449 void __pthread_do_exit (void *retval, char *currentframe)
450 __attribute__ ((__noreturn__));
451 void __pthread_destroy_specifics(void);
452 void __pthread_perform_cleanup(char *currentframe);
453 int __pthread_initialize_manager(void);
454 void __pthread_message(char * fmt, ...)
455 __attribute__ ((__format__ (printf, 1, 2)));
456 int __pthread_manager(void *reqfd);
457 int __pthread_manager_event(void *reqfd);
458 void __pthread_manager_sighandler(int sig);
459 void __pthread_reset_main_thread(void);
460 void __fresetlockfiles(void);
461 void __pthread_manager_adjust_prio(int thread_prio);
462 void __pthread_initialize_minimal (void);
464 extern void __pthread_exit (void *retval)
465 #if defined NOT_IN_libc && defined IS_IN_libpthread
470 extern int __pthread_attr_setguardsize __P ((pthread_attr_t *__attr,
471 size_t __guardsize));
472 extern int __pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr,
473 size_t *__guardsize));
474 extern int __pthread_attr_setstackaddr __P ((pthread_attr_t *__attr,
476 extern int __pthread_attr_getstackaddr __P ((__const pthread_attr_t *__attr,
477 void **__stackaddr));
478 extern int __pthread_attr_setstacksize __P ((pthread_attr_t *__attr,
479 size_t __stacksize));
480 extern int __pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr,
481 size_t *__stacksize));
482 extern int __pthread_getconcurrency __P ((void));
483 extern int __pthread_setconcurrency __P ((int __level));
484 extern void __pthread_kill_other_threads_np __P ((void));
486 extern void __pthread_restart_old(pthread_descr th);
487 extern void __pthread_suspend_old(pthread_descr self);
488 extern int __pthread_timedsuspend_old(pthread_descr self, const struct timespec *abstime);
490 extern void __pthread_restart_new(pthread_descr th);
491 extern void __pthread_suspend_new(pthread_descr self);
492 extern int __pthread_timedsuspend_new(pthread_descr self, const struct timespec *abstime);
494 extern void __pthread_wait_for_restart_signal(pthread_descr self);
496 /* Global pointers to old or new suspend functions */
498 extern void (*__pthread_restart)(pthread_descr);
499 extern void (*__pthread_suspend)(pthread_descr);
501 extern __typeof(pthread_mutex_init) __pthread_mutex_init attribute_hidden;
502 extern __typeof(pthread_mutex_destroy) __pthread_mutex_destroy attribute_hidden;
503 extern __typeof(pthread_mutex_lock) __pthread_mutex_lock attribute_hidden;
504 extern __typeof(pthread_mutex_trylock) __pthread_mutex_trylock attribute_hidden;
505 extern __typeof(pthread_mutex_unlock) __pthread_mutex_attribute_hidden;
507 /* Prototypes for some of the new semaphore functions. */
508 extern int __new_sem_post (sem_t * sem);
511 extern int __pthread_internal_tsd_set (int key, const void * pointer);
512 extern void * __pthread_internal_tsd_get (int key);
513 extern void ** __attribute__ ((__const__))
514 __pthread_internal_tsd_address (int key);
516 /* The functions called the signal events. */
517 extern void __linuxthreads_create_event (void);
518 extern void __linuxthreads_death_event (void);
519 extern void __linuxthreads_reap_event (void);
521 #include <pthread-functions.h>
523 extern int * __libc_pthread_init (const struct pthread_functions *functions);
525 #endif /* internals.h */