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 STRINGIFY(s) STRINGIFY2 (s)
40 #define STRINGIFY2(s) #s
41 #define VERSION STRINGIFY(__UCLIBC_MAJOR__) "." STRINGIFY(__UCLIBC_MINOR__) "." STRINGIFY(__UCLIBC_SUBLEVEL__)
44 # define THREAD_GETMEM(descr, member) descr->member
46 #ifndef THREAD_GETMEM_NC
47 # define THREAD_GETMEM_NC(descr, member) descr->member
50 # define THREAD_SETMEM(descr, member, value) descr->member = (value)
52 #ifndef THREAD_SETMEM_NC
53 # define THREAD_SETMEM_NC(descr, member, value) descr->member = (value)
56 /* Arguments passed to thread creation routine */
58 struct pthread_start_args {
59 void * (*start_routine)(void *); /* function to run */
60 void * arg; /* its argument */
61 sigset_t mask; /* initial signal mask for thread */
62 int schedpolicy; /* initial scheduling policy (if any) */
63 struct sched_param schedparam; /* initial scheduling parameters (if any) */
67 /* We keep thread specific data in a special data structure, a two-level
68 array. The top-level array contains pointers to dynamically allocated
69 arrays of a certain number of data pointers. So we can implement a
70 sparse array. Each dynamic second-level array has
71 PTHREAD_KEY_2NDLEVEL_SIZE
72 entries. This value shouldn't be too large. */
73 #define PTHREAD_KEY_2NDLEVEL_SIZE 32
75 /* We need to address PTHREAD_KEYS_MAX key with PTHREAD_KEY_2NDLEVEL_SIZE
76 keys in each subarray. */
77 #define PTHREAD_KEY_1STLEVEL_SIZE \
78 ((PTHREAD_KEYS_MAX + PTHREAD_KEY_2NDLEVEL_SIZE - 1) \
79 / PTHREAD_KEY_2NDLEVEL_SIZE)
81 typedef void (*destr_function)(void *);
83 struct pthread_key_struct {
84 int in_use; /* already allocated? */
85 destr_function destr; /* destruction routine */
89 #define PTHREAD_START_ARGS_INITIALIZER { NULL, NULL, {{0, }}, 0, { 0 } }
91 /* The type of thread descriptors */
93 typedef struct _pthread_descr_struct * pthread_descr;
95 /* Callback interface for removing the thread from waiting on an
96 object if it is cancelled while waiting or about to wait.
97 This hold a pointer to the object, and a pointer to a function
98 which ``extricates'' the thread from its enqueued state.
99 The function takes two arguments: pointer to the wait object,
100 and a pointer to the thread. It returns 1 if an extrication
101 actually occured, and hence the thread must also be signalled.
102 It returns 0 if the thread had already been extricated. */
104 typedef struct _pthread_extricate_struct {
106 int (*pu_extricate_func)(void *, pthread_descr);
107 } pthread_extricate_if;
109 /* Atomic counter made possible by compare_and_swap */
111 struct pthread_atomic {
116 /* Context info for read write locks. The pthread_rwlock_info structure
117 is information about a lock that has been read-locked by the thread
118 in whose list this structure appears. The pthread_rwlock_context
119 is embedded in the thread context and contains a pointer to the
120 head of the list of lock info structures, as well as a count of
121 read locks that are untracked, because no info structure could be
122 allocated for them. */
124 struct _pthread_rwlock_t;
126 typedef struct _pthread_rwlock_info {
127 struct _pthread_rwlock_info *pr_next;
128 struct _pthread_rwlock_t *pr_lock;
130 } pthread_readlock_info;
132 struct _pthread_descr_struct {
133 pthread_descr p_nextlive, p_prevlive;
134 /* Double chaining of active threads */
135 pthread_descr p_nextwaiting; /* Next element in the queue holding the thr */
136 pthread_descr p_nextlock; /* can be on a queue and waiting on a lock */
137 pthread_t p_tid; /* Thread identifier */
138 int p_pid; /* PID of Unix process */
139 int p_priority; /* Thread priority (== 0 if not realtime) */
140 struct _pthread_fastlock * p_lock; /* Spinlock for synchronized accesses */
141 int p_signal; /* last signal received */
142 sigjmp_buf * p_signal_jmp; /* where to siglongjmp on a signal or NULL */
143 sigjmp_buf * p_cancel_jmp; /* where to siglongjmp on a cancel or NULL */
144 char p_terminated; /* true if terminated e.g. by pthread_exit */
145 char p_detached; /* true if detached */
146 char p_exited; /* true if the assoc. process terminated */
147 void * p_retval; /* placeholder for return value */
148 int p_retcode; /* placeholder for return code */
149 pthread_descr p_joining; /* thread joining on that thread or NULL */
150 struct _pthread_cleanup_buffer * p_cleanup; /* cleanup functions */
151 char p_cancelstate; /* cancellation state */
152 char p_canceltype; /* cancellation type (deferred/async) */
153 char p_canceled; /* cancellation request pending */
154 int * p_errnop; /* pointer to used errno variable */
155 int p_errno; /* error returned by last system call */
156 int * p_h_errnop; /* pointer to used h_errno variable */
157 int p_h_errno; /* error returned by last netdb function */
158 char * p_in_sighandler; /* stack address of sighandler, or NULL */
159 char p_sigwaiting; /* true if a sigwait() is in progress */
160 struct pthread_start_args p_start_args; /* arguments for thread creation */
161 void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE]; /* thread-specific data */
162 void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */
163 int p_userstack; /* nonzero if the user provided the stack */
164 void *p_guardaddr; /* address of guard area or NULL */
165 size_t p_guardsize; /* size of guard area */
166 pthread_descr p_self; /* Pointer to this structure */
167 int p_nr; /* Index of descriptor in __pthread_handles */
168 int p_report_events; /* Nonzero if events must be reported. */
169 td_eventbuf_t p_eventbuf; /* Data for event. */
170 struct pthread_atomic p_resume_count; /* number of times restart() was
172 char p_woken_by_cancel; /* cancellation performed wakeup */
173 char p_condvar_avail; /* flag if conditional variable became avail */
174 char p_sem_avail; /* flag if semaphore became available */
175 pthread_extricate_if *p_extricate; /* See above */
176 pthread_readlock_info *p_readlock_list; /* List of readlock info structs */
177 pthread_readlock_info *p_readlock_free; /* Free list of structs */
178 int p_untracked_readlock_count; /* Readlocks not tracked by list */
179 /* New elements must be added at the end. */
180 #ifdef __UCLIBC_HAS_XLOCALE__
181 __locale_t locale; /* thread-specific locale from uselocale() only! */
182 #endif /* __UCLIBC_HAS_XLOCALE__ */
183 } __attribute__ ((aligned(32))); /* We need to align the structure so that
184 doubles are aligned properly. This is 8
185 bytes on MIPS and 16 bytes on MIPS64.
186 32 bytes might give better cache
189 /* The type of thread handles. */
191 typedef struct pthread_handle_struct * pthread_handle;
193 struct pthread_handle_struct {
194 struct _pthread_fastlock h_lock; /* Fast lock for sychronized access */
195 pthread_descr h_descr; /* Thread descriptor or NULL if invalid */
196 char * h_bottom; /* Lowest address in the stack thread */
199 /* The type of messages sent to the thread manager thread */
201 struct pthread_request {
202 pthread_descr req_thread; /* Thread doing the request */
203 enum { /* Request kind */
204 REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT,
205 REQ_POST, REQ_DEBUG, REQ_KICK
207 union { /* Arguments for request */
208 struct { /* For REQ_CREATE: */
209 const pthread_attr_t * attr; /* thread attributes */
210 void * (*fn)(void *); /* start function */
211 void * arg; /* argument to start function */
212 sigset_t mask; /* signal mask */
214 struct { /* For REQ_FREE: */
215 pthread_t thread_id; /* identifier of thread to free */
217 struct { /* For REQ_PROCESS_EXIT: */
218 int code; /* exit status */
220 void * post; /* For REQ_POST: the semaphore */
225 /* Signals used for suspend/restart and for cancellation notification. */
227 extern int __pthread_sig_restart;
228 extern int __pthread_sig_cancel;
230 /* Signal used for interfacing with gdb */
232 extern int __pthread_sig_debug;
234 /* Global array of thread handles, used for validating a thread id
235 and retrieving the corresponding thread descriptor. Also used for
236 mapping the available stack segments. */
238 extern struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX];
240 /* Descriptor of the initial thread */
242 extern struct _pthread_descr_struct __pthread_initial_thread;
244 /* Descriptor of the manager thread */
246 extern struct _pthread_descr_struct __pthread_manager_thread;
248 /* Descriptor of the main thread */
250 extern pthread_descr __pthread_main_thread;
252 /* Limit between the stack of the initial thread (above) and the
253 stacks of other threads (below). Aligned on a STACK_SIZE boundary.
254 Initially 0, meaning that the current thread is (by definition)
255 the initial thread. */
257 /* For non-MMU systems also remember to stack top of the initial thread.
258 * This is adapted when other stacks are malloc'ed since we don't know
259 * the bounds a-priori. -StS */
261 extern char *__pthread_initial_thread_bos;
262 #ifndef __ARCH_USE_MMU__
263 extern char *__pthread_initial_thread_tos;
264 #define NOMMU_INITIAL_THREAD_BOUNDS(tos,bos) \
265 if ((tos)>=__pthread_initial_thread_bos \
266 && (bos)<__pthread_initial_thread_tos) \
267 __pthread_initial_thread_bos = (tos)+1
269 #define NOMMU_INITIAL_THREAD_BOUNDS(tos,bos) /* empty */
270 #endif /* __ARCH_USE_MMU__ */
273 /* Indicate whether at least one thread has a user-defined stack (if 1),
274 or all threads have stacks supplied by LinuxThreads (if 0). */
276 extern int __pthread_nonstandard_stacks;
278 /* File descriptor for sending requests to the thread manager.
279 Initially -1, meaning that __pthread_initialize_manager must be called. */
281 extern int __pthread_manager_request;
283 /* Other end of the pipe for sending requests to the thread manager. */
285 extern int __pthread_manager_reader;
287 /* Limits of the thread manager stack. */
289 extern char *__pthread_manager_thread_bos;
290 extern char *__pthread_manager_thread_tos;
292 /* Pending request for a process-wide exit */
294 extern int __pthread_exit_requested, __pthread_exit_code;
296 /* Set to 1 by gdb if we're debugging */
298 extern volatile int __pthread_threads_debug;
300 /* Globally enabled events. */
301 extern volatile td_thr_events_t __pthread_threads_events;
303 /* Pointer to descriptor of thread with last event. */
304 extern volatile pthread_descr __pthread_last_event;
306 /* Return the handle corresponding to a thread id */
308 static inline pthread_handle thread_handle(pthread_t id)
310 return &__pthread_handles[id % PTHREAD_THREADS_MAX];
313 /* Validate a thread handle. Must have acquired h->h_spinlock before. */
315 static inline int invalid_handle(pthread_handle h, pthread_t id)
317 return h->h_descr == NULL || h->h_descr->p_tid != id;
320 /* Fill in defaults left unspecified by pt-machine.h. */
322 /* The page size we can get from the system. This should likely not be
323 changed by the machine file but, you never know. */
324 extern size_t __pagesize;
325 #include <bits/uClibc_page.h>
327 #define PAGE_SIZE (sysconf (_SC_PAGESIZE))
330 /* The max size of the thread stack segments. If the default
331 THREAD_SELF implementation is used, this must be a power of two and
332 a multiple of PAGE_SIZE. */
334 #ifdef __ARCH_USE_MMU__
335 #define STACK_SIZE (2 * 1024 * 1024)
337 #define STACK_SIZE (4 * __pagesize)
341 /* The initial size of the thread stack. Must be a multiple of PAGE_SIZE. */
342 #ifndef INITIAL_STACK_SIZE
343 #define INITIAL_STACK_SIZE (4 * __pagesize)
346 /* Size of the thread manager stack. The "- 32" avoids wasting space
347 with some malloc() implementations. */
348 #ifndef THREAD_MANAGER_STACK_SIZE
349 #define THREAD_MANAGER_STACK_SIZE (2 * __pagesize - 32)
352 /* The base of the "array" of thread stacks. The array will grow down from
353 here. Defaults to the calculated bottom of the initial application
355 #ifndef THREAD_STACK_START_ADDRESS
356 #define THREAD_STACK_START_ADDRESS __pthread_initial_thread_bos
359 /* Get some notion of the current stack. Need not be exactly the top
360 of the stack, just something somewhere in the current frame. */
361 #ifndef CURRENT_STACK_FRAME
362 #define CURRENT_STACK_FRAME ({ char __csf; &__csf; })
365 /* If MEMORY_BARRIER isn't defined in pt-machine.h, assume the
366 architecture doesn't need a memory barrier instruction (e.g. Intel
367 x86). Still we need the compiler to respect the barrier and emit
368 all outstanding operations which modify memory. Some architectures
369 distinguish between full, read and write barriers. */
370 #ifndef MEMORY_BARRIER
371 #define MEMORY_BARRIER() __asm__ ("" : : : "memory")
373 #ifndef READ_MEMORY_BARRIER
374 #define READ_MEMORY_BARRIER() MEMORY_BARRIER()
376 #ifndef WRITE_MEMORY_BARRIER
377 #define WRITE_MEMORY_BARRIER() MEMORY_BARRIER()
380 /* Recover thread descriptor for the current thread */
382 extern pthread_descr __pthread_find_self (void) __attribute__ ((const));
384 static inline pthread_descr thread_self (void) __attribute__ ((const));
385 static inline pthread_descr thread_self (void)
390 char *sp = CURRENT_STACK_FRAME;
391 #ifdef __ARCH_USE_MMU__
392 if (sp >= __pthread_initial_thread_bos)
393 return &__pthread_initial_thread;
394 else if (sp >= __pthread_manager_thread_bos
395 && sp < __pthread_manager_thread_tos)
396 return &__pthread_manager_thread;
397 else if (__pthread_nonstandard_stacks)
398 return __pthread_find_self();
400 return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1;
402 /* For non-MMU we need to be more careful about the initial thread stack.
403 * We refine the initial thread stack bounds dynamically as we allocate
404 * the other stack frame such that it doesn't overlap with them. Then
405 * we can be sure to pick the right thread according to the current SP */
407 /* Since we allow other stack frames to be above or below, we need to
408 * treat this case special. When pthread_initialize() wasn't called yet,
409 * only the initial thread is there. */
410 if (__pthread_initial_thread_bos == NULL) {
411 return &__pthread_initial_thread;
413 else if (sp >= __pthread_initial_thread_bos
414 && sp < __pthread_initial_thread_tos) {
415 return &__pthread_initial_thread;
417 else if (sp >= __pthread_manager_thread_bos
418 && sp < __pthread_manager_thread_tos) {
419 return &__pthread_manager_thread;
422 return __pthread_find_self();
424 #endif /* __ARCH_USE_MMU__ */
428 /* Max number of times we must spin on a spinlock calling sched_yield().
429 After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */
431 #ifndef MAX_SPIN_COUNT
432 #define MAX_SPIN_COUNT 50
435 /* Duration of sleep (in nanoseconds) when we can't acquire a spinlock
436 after MAX_SPIN_COUNT iterations of sched_yield().
437 With the 2.0 and 2.1 kernels, this MUST BE > 2ms.
438 (Otherwise the kernel does busy-waiting for realtime threads,
439 giving other threads no chance to run.) */
441 #ifndef SPIN_SLEEP_DURATION
442 #define SPIN_SLEEP_DURATION 2000001
445 /* Defined and used in libc.so. */
446 extern int __libc_multiple_threads attribute_hidden;
447 extern int __librt_multiple_threads;
449 /* Internal global functions */
451 void __pthread_do_exit (void *retval, char *currentframe)
452 __attribute__ ((__noreturn__));
453 void __pthread_destroy_specifics(void);
454 void __pthread_perform_cleanup(char *currentframe);
455 int __pthread_initialize_manager(void);
456 void __pthread_message(char * fmt, ...);
457 int __pthread_manager(void *reqfd);
458 int __pthread_manager_event(void *reqfd);
459 void __pthread_manager_sighandler(int sig);
460 void __pthread_reset_main_thread(void);
461 void __fresetlockfiles(void);
462 void __pthread_manager_adjust_prio(int thread_prio);
463 void __pthread_initialize_minimal (void);
465 extern void __pthread_exit (void *retval)
466 #if defined NOT_IN_libc && defined IS_IN_libpthread
471 extern int __pthread_attr_setguardsize __P ((pthread_attr_t *__attr,
472 size_t __guardsize));
473 extern int __pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr,
474 size_t *__guardsize));
475 extern int __pthread_attr_setstackaddr __P ((pthread_attr_t *__attr,
477 extern int __pthread_attr_getstackaddr __P ((__const pthread_attr_t *__attr,
478 void **__stackaddr));
479 extern int __pthread_attr_setstacksize __P ((pthread_attr_t *__attr,
480 size_t __stacksize));
481 extern int __pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr,
482 size_t *__stacksize));
483 extern int __pthread_getconcurrency __P ((void));
484 extern int __pthread_setconcurrency __P ((int __level));
485 extern void __pthread_kill_other_threads_np __P ((void));
487 extern void __pthread_restart_old(pthread_descr th);
488 extern void __pthread_suspend_old(pthread_descr self);
489 extern int __pthread_timedsuspend_old(pthread_descr self, const struct timespec *abstime);
491 extern void __pthread_restart_new(pthread_descr th);
492 extern void __pthread_suspend_new(pthread_descr self);
493 extern int __pthread_timedsuspend_new(pthread_descr self, const struct timespec *abstime);
495 extern void __pthread_wait_for_restart_signal(pthread_descr self);
497 /* Global pointers to old or new suspend functions */
499 extern void (*__pthread_restart)(pthread_descr);
500 extern void (*__pthread_suspend)(pthread_descr);
502 /* Prototypes for the function without cancelation support when the
503 normal version has it. */
504 extern __typeof(close) __libc_close;
505 extern __typeof(nanosleep) __libc_nanosleep;
506 extern __typeof(read) __libc_read;
507 extern __typeof(waitpid) __libc_waitpid;
508 extern __typeof(write) __libc_write;
510 extern __typeof(pthread_mutex_init) __pthread_mutex_init attribute_hidden;
511 extern __typeof(pthread_mutex_destroy) __pthread_mutex_destroy attribute_hidden;
512 extern __typeof(pthread_mutex_lock) __pthread_mutex_lock attribute_hidden;
513 extern __typeof(pthread_mutex_trylock) __pthread_mutex_trylock attribute_hidden;
514 extern __typeof(pthread_mutex_unlock) __pthread_mutex_attribute_hidden;
516 /* Prototypes for some of the new semaphore functions. */
517 extern int __new_sem_post (sem_t * sem);
520 extern int __pthread_internal_tsd_set (int key, const void * pointer);
521 extern void * __pthread_internal_tsd_get (int key);
522 extern void ** __attribute__ ((__const__))
523 __pthread_internal_tsd_address (int key);
525 /* The functions called the signal events. */
526 extern void __linuxthreads_create_event (void);
527 extern void __linuxthreads_death_event (void);
528 extern void __linuxthreads_reap_event (void);
530 #include <pthread-functions.h>
532 extern int * __libc_pthread_init (const struct pthread_functions *functions);
534 #endif /* internals.h */