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 */
27 #include <stackinfo.h>
28 #include <sys/types.h>
29 #include <bits/libc-tsd.h> /* for _LIBC_TSD_KEY_N */
31 extern long int testandset (int *spinlock
);
32 extern int __compare_and_swap (long int *p
, long int oldval
, long int newval
);
34 #include "pt-machine.h"
35 #include "semaphore.h"
36 #include "../linuxthreads_db/thread_dbP.h"
37 #include <hp-timing.h>
40 # define THREAD_GETMEM(descr, member) descr->member
42 #ifndef THREAD_GETMEM_NC
43 # define THREAD_GETMEM_NC(descr, member) descr->member
46 # define THREAD_SETMEM(descr, member, value) descr->member = (value)
48 #ifndef THREAD_SETMEM_NC
49 # define THREAD_SETMEM_NC(descr, member, value) descr->member = (value)
52 /* Arguments passed to thread creation routine */
54 struct pthread_start_args
{
55 void * (*start_routine
)(void *); /* function to run */
56 void * arg
; /* its argument */
57 sigset_t mask
; /* initial signal mask for thread */
58 int schedpolicy
; /* initial scheduling policy (if any) */
59 struct sched_param schedparam
; /* initial scheduling parameters (if any) */
63 /* We keep thread specific data in a special data structure, a two-level
64 array. The top-level array contains pointers to dynamically allocated
65 arrays of a certain number of data pointers. So we can implement a
66 sparse array. Each dynamic second-level array has
67 PTHREAD_KEY_2NDLEVEL_SIZE
68 entries. This value shouldn't be too large. */
69 #define PTHREAD_KEY_2NDLEVEL_SIZE 32
71 /* We need to address PTHREAD_KEYS_MAX key with PTHREAD_KEY_2NDLEVEL_SIZE
72 keys in each subarray. */
73 #define PTHREAD_KEY_1STLEVEL_SIZE \
74 ((PTHREAD_KEYS_MAX + PTHREAD_KEY_2NDLEVEL_SIZE - 1) \
75 / PTHREAD_KEY_2NDLEVEL_SIZE)
77 typedef void (*destr_function
)(void *);
79 struct pthread_key_struct
{
80 int in_use
; /* already allocated? */
81 destr_function destr
; /* destruction routine */
85 #define PTHREAD_START_ARGS_INITIALIZER(fct) \
86 { (void *(*) (void *)) fct, NULL, {{0, }}, 0, { 0 } }
88 /* The type of thread descriptors */
90 typedef struct _pthread_descr_struct
* pthread_descr
;
92 /* Callback interface for removing the thread from waiting on an
93 object if it is cancelled while waiting or about to wait.
94 This hold a pointer to the object, and a pointer to a function
95 which ``extricates'' the thread from its enqueued state.
96 The function takes two arguments: pointer to the wait object,
97 and a pointer to the thread. It returns 1 if an extrication
98 actually occured, and hence the thread must also be signalled.
99 It returns 0 if the thread had already been extricated. */
101 typedef struct _pthread_extricate_struct
{
103 int (*pu_extricate_func
)(void *, pthread_descr
);
104 } pthread_extricate_if
;
106 /* Atomic counter made possible by compare_and_swap */
108 struct pthread_atomic
{
113 /* Context info for read write locks. The pthread_rwlock_info structure
114 is information about a lock that has been read-locked by the thread
115 in whose list this structure appears. The pthread_rwlock_context
116 is embedded in the thread context and contains a pointer to the
117 head of the list of lock info structures, as well as a count of
118 read locks that are untracked, because no info structure could be
119 allocated for them. */
121 struct _pthread_rwlock_t
;
123 typedef struct _pthread_rwlock_info
{
124 struct _pthread_rwlock_info
*pr_next
;
125 struct _pthread_rwlock_t
*pr_lock
;
127 } pthread_readlock_info
;
129 struct _pthread_descr_struct
{
132 pthread_descr self
; /* Pointer to this structure */
136 pthread_descr p_nextlive
, p_prevlive
;
137 /* Double chaining of active threads */
138 pthread_descr p_nextwaiting
; /* Next element in the queue holding the thr */
139 pthread_descr p_nextlock
; /* can be on a queue and waiting on a lock */
140 pthread_t p_tid
; /* Thread identifier */
141 int p_pid
; /* PID of Unix process */
142 int p_priority
; /* Thread priority (== 0 if not realtime) */
143 struct _pthread_fastlock
* p_lock
; /* Spinlock for synchronized accesses */
144 int p_signal
; /* last signal received */
145 sigjmp_buf
* p_signal_jmp
; /* where to siglongjmp on a signal or NULL */
146 sigjmp_buf
* p_cancel_jmp
; /* where to siglongjmp on a cancel or NULL */
147 char p_terminated
; /* true if terminated e.g. by pthread_exit */
148 char p_detached
; /* true if detached */
149 char p_exited
; /* true if the assoc. process terminated */
150 void * p_retval
; /* placeholder for return value */
151 int p_retcode
; /* placeholder for return code */
152 pthread_descr p_joining
; /* thread joining on that thread or NULL */
153 struct _pthread_cleanup_buffer
* p_cleanup
; /* cleanup functions */
154 char p_cancelstate
; /* cancellation state */
155 char p_canceltype
; /* cancellation type (deferred/async) */
156 char p_canceled
; /* cancellation request pending */
157 int * p_errnop
; /* pointer to used errno variable */
158 int p_errno
; /* error returned by last system call */
159 int * p_h_errnop
; /* pointer to used h_errno variable */
160 int p_h_errno
; /* error returned by last netdb function */
161 char * p_in_sighandler
; /* stack address of sighandler, or NULL */
162 char p_sigwaiting
; /* true if a sigwait() is in progress */
163 struct pthread_start_args p_start_args
; /* arguments for thread creation */
164 void ** p_specific
[PTHREAD_KEY_1STLEVEL_SIZE
]; /* thread-specific data */
165 void * p_libc_specific
[_LIBC_TSD_KEY_N
]; /* thread-specific data for libc */
166 int p_userstack
; /* nonzero if the user provided the stack */
167 void *p_guardaddr
; /* address of guard area or NULL */
168 size_t p_guardsize
; /* size of guard area */
169 int p_nr
; /* Index of descriptor in __pthread_handles */
170 int p_report_events
; /* Nonzero if events must be reported. */
171 td_eventbuf_t p_eventbuf
; /* Data for event. */
172 struct pthread_atomic p_resume_count
; /* number of times restart() was
174 char p_woken_by_cancel
; /* cancellation performed wakeup */
175 char p_condvar_avail
; /* flag if conditional variable became avail */
176 char p_sem_avail
; /* flag if semaphore became available */
177 pthread_extricate_if
*p_extricate
; /* See above */
178 pthread_readlock_info
*p_readlock_list
; /* List of readlock info structs */
179 pthread_readlock_info
*p_readlock_free
; /* Free list of structs */
180 int p_untracked_readlock_count
; /* Readlocks not tracked by list */
181 struct __res_state
*p_resp
; /* Pointer to resolver state */
182 struct __res_state p_res
; /* per-thread resolver state */
183 int p_inheritsched
; /* copied from the thread attribute */
185 hp_timing_t p_cpuclock_offset
; /* Initial CPU clock for thread. */
187 /* New elements must be added at the end. */
188 } __attribute__ ((aligned(32))); /* We need to align the structure so that
189 doubles are aligned properly. This is 8
190 bytes on MIPS and 16 bytes on MIPS64.
191 32 bytes might give better cache
195 /* The type of thread handles. */
197 typedef struct pthread_handle_struct
* pthread_handle
;
199 struct pthread_handle_struct
{
200 struct _pthread_fastlock h_lock
; /* Fast lock for sychronized access */
201 pthread_descr h_descr
; /* Thread descriptor or NULL if invalid */
202 char * h_bottom
; /* Lowest address in the stack thread */
205 /* The type of messages sent to the thread manager thread */
207 struct pthread_request
{
208 pthread_descr req_thread
; /* Thread doing the request */
209 enum { /* Request kind */
210 REQ_CREATE
, REQ_FREE
, REQ_PROCESS_EXIT
, REQ_MAIN_THREAD_EXIT
,
211 REQ_POST
, REQ_DEBUG
, REQ_KICK
213 union { /* Arguments for request */
214 struct { /* For REQ_CREATE: */
215 const pthread_attr_t
* attr
; /* thread attributes */
216 void * (*fn
)(void *); /* start function */
217 void * arg
; /* argument to start function */
218 sigset_t mask
; /* signal mask */
220 struct { /* For REQ_FREE: */
221 pthread_t thread_id
; /* identifier of thread to free */
223 struct { /* For REQ_PROCESS_EXIT: */
224 int code
; /* exit status */
226 void * post
; /* For REQ_POST: the semaphore */
231 /* Signals used for suspend/restart and for cancellation notification. */
233 extern int __pthread_sig_restart
;
234 extern int __pthread_sig_cancel
;
236 /* Signal used for interfacing with gdb */
238 extern int __pthread_sig_debug
;
240 /* Global array of thread handles, used for validating a thread id
241 and retrieving the corresponding thread descriptor. Also used for
242 mapping the available stack segments. */
244 extern struct pthread_handle_struct __pthread_handles
[PTHREAD_THREADS_MAX
];
246 /* Descriptor of the initial thread */
248 extern struct _pthread_descr_struct __pthread_initial_thread
;
250 /* Descriptor of the manager thread */
252 extern struct _pthread_descr_struct __pthread_manager_thread
;
254 /* Descriptor of the main thread */
256 extern pthread_descr __pthread_main_thread
;
258 /* Limit between the stack of the initial thread (above) and the
259 stacks of other threads (below). Aligned on a STACK_SIZE boundary.
260 Initially 0, meaning that the current thread is (by definition)
261 the initial thread. */
263 extern char *__pthread_initial_thread_bos
;
265 /* Indicate whether at least one thread has a user-defined stack (if 1),
266 or all threads have stacks supplied by LinuxThreads (if 0). */
268 extern int __pthread_nonstandard_stacks
;
270 /* File descriptor for sending requests to the thread manager.
271 Initially -1, meaning that __pthread_initialize_manager must be called. */
273 extern int __pthread_manager_request
;
275 /* Other end of the pipe for sending requests to the thread manager. */
277 extern int __pthread_manager_reader
;
279 /* Limits of the thread manager stack. */
281 extern char *__pthread_manager_thread_bos
;
282 extern char *__pthread_manager_thread_tos
;
284 #ifdef FLOATING_STACKS
285 /* Maximum stack size. */
286 extern size_t __pthread_max_stacksize
;
289 /* Pending request for a process-wide exit */
291 extern int __pthread_exit_requested
, __pthread_exit_code
;
293 /* Set to 1 by gdb if we're debugging */
295 extern volatile int __pthread_threads_debug
;
297 /* Globally enabled events. */
298 extern volatile td_thr_events_t __pthread_threads_events
;
300 /* Pointer to descriptor of thread with last event. */
301 extern volatile pthread_descr __pthread_last_event
;
303 /* Flag which tells whether we are executing on SMP kernel. */
304 extern int __pthread_smp_kernel
;
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
|| h
->h_descr
->p_terminated
;
320 static inline int nonexisting_handle(pthread_handle h
, pthread_t id
)
322 return h
->h_descr
== NULL
|| h
->h_descr
->p_tid
!= id
;
325 /* Fill in defaults left unspecified by pt-machine.h. */
327 /* We round up a value with page size. */
329 #define page_roundup(v,p) ((((size_t) (v)) + (p) - 1) & ~((p) - 1))
332 /* The page size we can get from the system. This should likely not be
333 changed by the machine file but, you never know. */
335 #define PAGE_SIZE (sysconf (_SC_PAGE_SIZE))
338 /* The max size of the thread stack segments. If the default
339 THREAD_SELF implementation is used, this must be a power of two and
340 a multiple of PAGE_SIZE. */
342 #define STACK_SIZE (2 * 1024 * 1024)
345 /* The initial size of the thread stack. Must be a multiple of PAGE_SIZE. */
346 #ifndef INITIAL_STACK_SIZE
347 #define INITIAL_STACK_SIZE (4 * PAGE_SIZE)
350 /* Size of the thread manager stack. The "- 32" avoids wasting space
351 with some malloc() implementations. */
352 #ifndef THREAD_MANAGER_STACK_SIZE
353 #define THREAD_MANAGER_STACK_SIZE (2 * PAGE_SIZE - 32)
356 /* The base of the "array" of thread stacks. The array will grow down from
357 here. Defaults to the calculated bottom of the initial application
359 #ifndef THREAD_STACK_START_ADDRESS
360 #define THREAD_STACK_START_ADDRESS __pthread_initial_thread_bos
363 /* Get some notion of the current stack. Need not be exactly the top
364 of the stack, just something somewhere in the current frame. */
365 #ifndef CURRENT_STACK_FRAME
366 #define CURRENT_STACK_FRAME ({ char __csf; &__csf; })
369 /* Recover thread descriptor for the current thread */
371 extern pthread_descr
__pthread_find_self (void) __attribute__ ((const));
373 static inline pthread_descr
thread_self (void) __attribute__ ((const));
374 static inline pthread_descr
thread_self (void)
379 char *sp
= CURRENT_STACK_FRAME
;
380 if (sp
>= __pthread_initial_thread_bos
)
381 return &__pthread_initial_thread
;
382 else if (sp
>= __pthread_manager_thread_bos
383 && sp
< __pthread_manager_thread_tos
)
384 return &__pthread_manager_thread
;
385 else if (__pthread_nonstandard_stacks
)
386 return __pthread_find_self();
388 #ifdef _STACK_GROWS_DOWN
389 return (pthread_descr
)(((unsigned long)sp
| (STACK_SIZE
-1))+1) - 1;
391 return (pthread_descr
)((unsigned long)sp
&~ (STACK_SIZE
-1));
396 /* If MEMORY_BARRIER isn't defined in pt-machine.h, assume the architecture
397 doesn't need a memory barrier instruction (e.g. Intel x86). Some
398 architectures distinguish between full, read and write barriers. */
400 #ifndef MEMORY_BARRIER
401 #define MEMORY_BARRIER()
403 #ifndef READ_MEMORY_BARRIER
404 #define READ_MEMORY_BARRIER() MEMORY_BARRIER()
406 #ifndef WRITE_MEMORY_BARRIER
407 #define WRITE_MEMORY_BARRIER() MEMORY_BARRIER()
410 /* Max number of times we must spin on a spinlock calling sched_yield().
411 After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */
413 #ifndef MAX_SPIN_COUNT
414 #define MAX_SPIN_COUNT 50
417 /* Duration of sleep (in nanoseconds) when we can't acquire a spinlock
418 after MAX_SPIN_COUNT iterations of sched_yield().
419 With the 2.0 and 2.1 kernels, this MUST BE > 2ms.
420 (Otherwise the kernel does busy-waiting for realtime threads,
421 giving other threads no chance to run.) */
423 #ifndef SPIN_SLEEP_DURATION
424 #define SPIN_SLEEP_DURATION 2000001
431 #define ASSERT assert
432 #define MSG __pthread_message
435 #define MSG(msg,arg...)
438 /* Internal global functions */
440 extern void __pthread_do_exit (void *retval
, char *currentframe
)
441 __attribute__ ((__noreturn__
));
442 extern void __pthread_destroy_specifics (void);
443 extern void __pthread_perform_cleanup (char *currentframe
);
444 extern void __pthread_init_max_stacksize (void);
445 extern int __pthread_initialize_manager (void);
446 extern void __pthread_message (char * fmt
, ...);
447 extern int __pthread_manager (void *reqfd
);
448 extern int __pthread_manager_event (void *reqfd
);
449 extern void __pthread_manager_sighandler (int sig
);
450 extern void __pthread_reset_main_thread (void);
451 extern void __pthread_once_fork_prepare (void);
452 extern void __pthread_once_fork_parent (void);
453 extern void __pthread_once_fork_child (void);
454 extern void __flockfilelist (void);
455 extern void __funlockfilelist (void);
456 extern void __fresetlockfiles (void);
457 extern void __pthread_manager_adjust_prio (int thread_prio
);
458 extern void __pthread_initialize_minimal (void);
460 extern int __pthread_attr_setguardsize (pthread_attr_t
*__attr
,
462 extern int __pthread_attr_getguardsize (const pthread_attr_t
*__attr
,
463 size_t *__guardsize
);
464 extern int __pthread_attr_setstackaddr (pthread_attr_t
*__attr
,
466 extern int __pthread_attr_getstackaddr (const pthread_attr_t
*__attr
,
468 extern int __pthread_attr_setstacksize (pthread_attr_t
*__attr
,
470 extern int __pthread_attr_getstacksize (const pthread_attr_t
*__attr
,
471 size_t *__stacksize
);
472 extern int __pthread_attr_setstack (pthread_attr_t
*__attr
, void *__stackaddr
,
474 extern int __pthread_attr_getstack (const pthread_attr_t
*__attr
, void **__stackaddr
,
475 size_t *__stacksize
);
476 extern int __pthread_getconcurrency (void);
477 extern int __pthread_setconcurrency (int __level
);
478 extern int __pthread_mutex_timedlock (pthread_mutex_t
*__mutex
,
479 const struct timespec
*__abstime
);
480 extern int __pthread_mutexattr_getpshared (const pthread_mutexattr_t
*__attr
,
482 extern int __pthread_mutexattr_setpshared (pthread_mutexattr_t
*__attr
,
484 extern int __pthread_mutexattr_gettype (const pthread_mutexattr_t
*__attr
,
486 extern void __pthread_kill_other_threads_np (void);
488 extern void __pthread_restart_old(pthread_descr th
);
489 extern void __pthread_suspend_old(pthread_descr self
);
490 extern int __pthread_timedsuspend_old(pthread_descr self
, const struct timespec
*abs
);
492 extern void __pthread_restart_new(pthread_descr th
);
493 extern void __pthread_suspend_new(pthread_descr self
);
494 extern int __pthread_timedsuspend_new(pthread_descr self
, const struct timespec
*abs
);
496 extern void __pthread_wait_for_restart_signal(pthread_descr self
);
498 extern int __pthread_yield (void);
500 extern int __pthread_rwlock_timedrdlock (pthread_rwlock_t
*__restrict __rwlock
,
501 __const
struct timespec
*__restrict
503 extern int __pthread_rwlock_timedwrlock (pthread_rwlock_t
*__restrict __rwlock
,
504 __const
struct timespec
*__restrict
506 extern int __pthread_rwlockattr_destroy (pthread_rwlockattr_t
*__attr
);
508 extern int __pthread_barrierattr_getpshared (__const pthread_barrierattr_t
*
510 int *__restrict __pshared
);
512 extern int __pthread_spin_lock (pthread_spinlock_t
*__lock
);
513 extern int __pthread_spin_trylock (pthread_spinlock_t
*__lock
);
514 extern int __pthread_spin_unlock (pthread_spinlock_t
*__lock
);
515 extern int __pthread_spin_init (pthread_spinlock_t
*__lock
, int __pshared
);
516 extern int __pthread_spin_destroy (pthread_spinlock_t
*__lock
);
518 extern int __pthread_clock_gettime (hp_timing_t freq
, struct timespec
*tp
);
519 extern void __pthread_clock_settime (hp_timing_t offset
);
522 /* Global pointers to old or new suspend functions */
524 extern void (*__pthread_restart
)(pthread_descr
);
525 extern void (*__pthread_suspend
)(pthread_descr
);
526 extern int (*__pthread_timedsuspend
)(pthread_descr
, const struct timespec
*);
528 /* Prototypes for the function without cancelation support when the
529 normal version has it. */
530 extern int __libc_close (int fd
);
531 extern int __libc_nanosleep (const struct timespec
*requested_time
,
532 struct timespec
*remaining
);
533 /* Prototypes for some of the new semaphore functions. */
534 extern int __new_sem_post (sem_t
* sem
);
535 extern int __new_sem_init (sem_t
*__sem
, int __pshared
, unsigned int __value
);
536 extern int __new_sem_wait (sem_t
*__sem
);
537 extern int __new_sem_trywait (sem_t
*__sem
);
538 extern int __new_sem_getvalue (sem_t
*__restrict __sem
, int *__restrict __sval
);
539 extern int __new_sem_destroy (sem_t
*__sem
);
541 /* Prototypes for compatibility functions. */
542 extern int __pthread_attr_init_2_1 (pthread_attr_t
*__attr
);
543 extern int __pthread_attr_init_2_0 (pthread_attr_t
*__attr
);
544 extern int __pthread_create_2_1 (pthread_t
*__restrict __thread
,
545 const pthread_attr_t
*__attr
,
546 void *(*__start_routine
) (void *),
547 void *__restrict __arg
);
548 extern int __pthread_create_2_0 (pthread_t
*__restrict thread
,
549 const pthread_attr_t
*__attr
,
550 void *(*__start_routine
) (void *),
551 void *__restrict arg
);
553 /* The functions called the signal events. */
554 extern void __linuxthreads_create_event (void);
555 extern void __linuxthreads_death_event (void);
556 extern void __linuxthreads_reap_event (void);
558 /* This function is called to initialize the pthread library. */
559 extern void __pthread_initialize (void);
561 #endif /* internals.h */