365 lines
12 KiB
C
365 lines
12 KiB
C
/* Internal defenitions for pthreads library.
|
||
Copyright (C) 2000-2022 Free Software Foundation, Inc.
|
||
This file is part of the GNU C Library.
|
||
|
||
The GNU C Library is free software; you can redistribute it and/or
|
||
modify it under the terms of the GNU Lesser General Public
|
||
License as published by the Free Software Foundation; either
|
||
version 2.1 of the License, or (at your option) any later version.
|
||
|
||
The GNU C Library is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
Lesser General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Lesser General Public
|
||
License along with the GNU C Library; if not, see
|
||
<https://www.gnu.org/licenses/>. */
|
||
|
||
#ifndef _PT_INTERNAL_H
|
||
#define _PT_INTERNAL_H 1
|
||
|
||
#include <pthread.h>
|
||
#include <stddef.h>
|
||
#include <sched.h>
|
||
#include <signal.h>
|
||
#include <assert.h>
|
||
#include <bits/types/res_state.h>
|
||
|
||
#include <atomic.h>
|
||
|
||
#include <pt-key.h>
|
||
|
||
#include <pt-sysdep.h>
|
||
#include <pt-machdep.h>
|
||
|
||
#if IS_IN (libpthread)
|
||
# include <ldsodefs.h>
|
||
#endif
|
||
|
||
#include <tls.h>
|
||
|
||
/* Thread state. */
|
||
enum pthread_state
|
||
{
|
||
/* The thread is running and joinable. */
|
||
PTHREAD_JOINABLE = 0,
|
||
/* The thread is running and detached. */
|
||
PTHREAD_DETACHED,
|
||
/* A joinable thread exited and its return code is available. */
|
||
PTHREAD_EXITED,
|
||
};
|
||
|
||
#ifndef PTHREAD_KEY_MEMBERS
|
||
# define PTHREAD_KEY_MEMBERS
|
||
#endif
|
||
|
||
#ifndef PTHREAD_SYSDEP_MEMBERS
|
||
# define PTHREAD_SYSDEP_MEMBERS
|
||
#endif
|
||
|
||
/* This structure describes a POSIX thread. */
|
||
struct __pthread
|
||
{
|
||
/* Thread ID. */
|
||
pthread_t thread;
|
||
|
||
unsigned int nr_refs; /* Detached threads have a self reference only,
|
||
while joinable threads have two references.
|
||
These are used to keep the structure valid at
|
||
thread destruction. Detaching/joining a thread
|
||
drops a reference. */
|
||
|
||
/* Cancellation. */
|
||
pthread_mutex_t cancel_lock; /* Protect cancel_xxx members. */
|
||
void (*cancel_hook) (void *); /* Called to unblock a thread blocking
|
||
in a cancellation point (namely,
|
||
__pthread_cond_timedwait_internal). */
|
||
void *cancel_hook_arg;
|
||
int cancel_state;
|
||
int cancel_type;
|
||
int cancel_pending;
|
||
|
||
/* Thread stack. */
|
||
void *stackaddr;
|
||
size_t stacksize;
|
||
size_t guardsize;
|
||
int stack; /* Nonzero if the stack was allocated. */
|
||
|
||
/* Exit status. */
|
||
void *status;
|
||
|
||
/* Thread state. */
|
||
enum pthread_state state;
|
||
pthread_mutex_t state_lock; /* Locks the state. */
|
||
pthread_cond_t state_cond; /* Signalled when the state changes. */
|
||
bool terminated; /* Whether the kernel thread is over
|
||
and we can reuse this structure. */
|
||
|
||
/* Resolver state. */
|
||
struct __res_state res_state;
|
||
|
||
/* Indicates whether is a C11 thread created by thrd_creat. */
|
||
bool c11;
|
||
|
||
/* Initial sigset for the thread. */
|
||
sigset_t init_sigset;
|
||
|
||
/* Thread context. */
|
||
struct pthread_mcontext mcontext;
|
||
|
||
PTHREAD_KEY_MEMBERS
|
||
|
||
PTHREAD_SYSDEP_MEMBERS
|
||
|
||
tcbhead_t *tcb;
|
||
|
||
/* Queue links. Since PREVP is used to determine if a thread has been
|
||
awaken, it must be protected by the queue lock. */
|
||
struct __pthread *next, **prevp;
|
||
};
|
||
|
||
/* Enqueue an element THREAD on the queue *HEAD. */
|
||
static inline void
|
||
__pthread_enqueue (struct __pthread **head, struct __pthread *thread)
|
||
{
|
||
assert (thread->prevp == 0);
|
||
|
||
thread->next = *head;
|
||
thread->prevp = head;
|
||
if (*head)
|
||
(*head)->prevp = &thread->next;
|
||
*head = thread;
|
||
}
|
||
|
||
/* Dequeue the element THREAD from the queue it is connected to. */
|
||
static inline void
|
||
__pthread_dequeue (struct __pthread *thread)
|
||
{
|
||
assert (thread);
|
||
assert (thread->prevp);
|
||
|
||
if (thread->next)
|
||
thread->next->prevp = thread->prevp;
|
||
*thread->prevp = thread->next;
|
||
thread->prevp = 0;
|
||
}
|
||
|
||
/* Iterate over QUEUE storing each element in ELEMENT. */
|
||
#define __pthread_queue_iterate(queue, element) \
|
||
for (struct __pthread *__pdi_next = (queue); \
|
||
((element) = __pdi_next) \
|
||
&& ((__pdi_next = __pdi_next->next), \
|
||
1); \
|
||
)
|
||
|
||
/* Iterate over QUEUE dequeuing each element, storing it in
|
||
ELEMENT. */
|
||
#define __pthread_dequeuing_iterate(queue, element) \
|
||
for (struct __pthread *__pdi_next = (queue); \
|
||
((element) = __pdi_next) \
|
||
&& ((__pdi_next = __pdi_next->next), \
|
||
((element)->prevp = 0), \
|
||
1); \
|
||
)
|
||
|
||
/* The total number of threads currently active. */
|
||
extern unsigned int __pthread_total;
|
||
|
||
/* Concurrency hint. */
|
||
extern int __pthread_concurrency;
|
||
|
||
/* The size of the thread ID lookup table. */
|
||
extern int __pthread_max_threads;
|
||
|
||
#define __pthread_getid(thread) \
|
||
({ struct __pthread *__t = NULL; \
|
||
__libc_rwlock_rdlock (GL (dl_pthread_threads_lock)); \
|
||
if (thread <= __pthread_max_threads) \
|
||
__t = GL (dl_pthread_threads)[thread - 1]; \
|
||
__libc_rwlock_unlock (GL (dl_pthread_threads_lock)); \
|
||
__t; })
|
||
|
||
#define __pthread_setid(thread, pthread) \
|
||
__libc_rwlock_wrlock (GL (dl_pthread_threads_lock)); \
|
||
GL (dl_pthread_threads)[thread - 1] = pthread; \
|
||
__libc_rwlock_unlock (GL (dl_pthread_threads_lock));
|
||
|
||
/* Similar to pthread_self, but returns the thread descriptor instead
|
||
of the thread ID. */
|
||
#ifndef _pthread_self
|
||
extern struct __pthread *_pthread_self (void);
|
||
#endif
|
||
|
||
/* Stores the stack of cleanup handlers for the thread. */
|
||
extern __thread struct __pthread_cancelation_handler *__pthread_cleanup_stack;
|
||
|
||
|
||
/* Initialize the pthreads library. */
|
||
extern void ___pthread_init (void);
|
||
|
||
/* Internal version of pthread_create. Rather than return the new
|
||
tid, we return the whole __pthread structure in *PTHREAD. */
|
||
extern int __pthread_create_internal (struct __pthread **__restrict pthread,
|
||
const pthread_attr_t *__restrict attr,
|
||
void *(*start_routine) (void *),
|
||
void *__restrict arg);
|
||
|
||
/* Allocate a new thread structure and a pthread thread ID (but not a
|
||
kernel thread or a stack). THREAD has one reference. */
|
||
extern int __pthread_alloc (struct __pthread **thread);
|
||
|
||
/* Deallocate the content of the thread structure. This is the dual of
|
||
__pthread_alloc (N.B. it does not call __pthread_stack_dealloc nor
|
||
__pthread_thread_terminate). THREAD loses one reference, and if
|
||
if the reference counter drops to 0 this returns 1, and the caller has
|
||
to call __pthread_dealloc_finish when it is really finished with using
|
||
THREAD. */
|
||
extern void __pthread_dealloc (struct __pthread *thread);
|
||
|
||
/* Confirm deallocating the thread structure. Before calling this
|
||
the structure will not be reused yet. */
|
||
extern void __pthread_dealloc_finish (struct __pthread *pthread);
|
||
|
||
|
||
/* Allocate a stack of size STACKSIZE. The stack base shall be
|
||
returned in *STACKADDR. */
|
||
extern int __pthread_stack_alloc (void **stackaddr, size_t stacksize);
|
||
|
||
/* Deallocate the stack STACKADDR of size STACKSIZE. */
|
||
extern void __pthread_stack_dealloc (void *stackaddr, size_t stacksize);
|
||
|
||
|
||
/* Setup thread THREAD's context. */
|
||
extern int __pthread_setup (struct __pthread *__restrict thread,
|
||
void (*entry_point) (struct __pthread *,
|
||
void *(*)(void *),
|
||
void *),
|
||
void *(*start_routine) (void *),
|
||
void *__restrict arg);
|
||
|
||
|
||
/* Allocate a kernel thread (and any miscellaneous system dependent
|
||
resources) for THREAD; it must not be placed on the run queue. */
|
||
extern int __pthread_thread_alloc (struct __pthread *thread);
|
||
|
||
/* Start THREAD making it eligible to run. */
|
||
extern int __pthread_thread_start (struct __pthread *thread);
|
||
|
||
/* Terminate the kernel thread associated with THREAD, and deallocate its
|
||
stack as well as any other kernel resource associated with it.
|
||
In addition, THREAD looses one reference.
|
||
|
||
This function can be called by any thread, including the target thread.
|
||
Since some resources that are destroyed along the kernel thread are
|
||
stored in thread-local variables, the conditions required for this
|
||
function to behave correctly are a bit unusual : as long as the target
|
||
thread hasn't been started, any thread can terminate it, but once it
|
||
has started, no other thread can terminate it, so that thread-local
|
||
variables created by that thread are correctly released. */
|
||
extern void __pthread_thread_terminate (struct __pthread *thread);
|
||
|
||
|
||
/* Called by a thread just before it calls the provided start
|
||
routine. */
|
||
extern void __pthread_startup (void);
|
||
|
||
/* Block THREAD. */
|
||
extern void __pthread_block (struct __pthread *thread);
|
||
|
||
/* Block THREAD until *ABSTIME is reached. */
|
||
extern error_t __pthread_timedblock (struct __pthread *__restrict thread,
|
||
const struct timespec *__restrict abstime,
|
||
clockid_t clock_id);
|
||
|
||
/* Block THREAD with interrupts. */
|
||
extern error_t __pthread_block_intr (struct __pthread *thread);
|
||
|
||
/* Block THREAD until *ABSTIME is reached, with interrupts. */
|
||
extern error_t __pthread_timedblock_intr (struct __pthread *__restrict thread,
|
||
const struct timespec *__restrict abstime,
|
||
clockid_t clock_id);
|
||
|
||
/* Wakeup THREAD. */
|
||
extern void __pthread_wakeup (struct __pthread *thread);
|
||
|
||
|
||
/* Perform a cancelation. The CANCEL_LOCK member of the given thread must
|
||
be locked before calling this function, which must unlock it. */
|
||
extern int __pthread_do_cancel (struct __pthread *thread);
|
||
|
||
|
||
/* Initialize the thread specific data structures. THREAD must be the
|
||
calling thread. */
|
||
extern error_t __pthread_init_specific (struct __pthread *thread);
|
||
|
||
/* Call the destructors on all of the thread specific data in THREAD.
|
||
THREAD must be the calling thread. */
|
||
extern void __pthread_destroy_specific (struct __pthread *thread);
|
||
|
||
|
||
/* Initialize newly create thread *THREAD's signal state data
|
||
structures. */
|
||
extern error_t __pthread_sigstate_init (struct __pthread *thread);
|
||
|
||
/* Destroy the signal state data structures associcated with thread
|
||
*THREAD. */
|
||
extern void __pthread_sigstate_destroy (struct __pthread *thread);
|
||
|
||
/* Modify thread *THREAD's signal state. */
|
||
extern error_t __pthread_sigstate (struct __pthread *__restrict thread, int how,
|
||
const sigset_t *__restrict set,
|
||
sigset_t *__restrict oset,
|
||
int clear_pending);
|
||
|
||
/* If supported, check that MUTEX is locked by the caller. */
|
||
extern int __pthread_mutex_checklocked (pthread_mutex_t *mtx);
|
||
|
||
|
||
/* Default thread attributes. */
|
||
extern struct __pthread_attr __pthread_default_attr;
|
||
|
||
/* Default barrier attributes. */
|
||
extern const struct __pthread_barrierattr __pthread_default_barrierattr;
|
||
|
||
/* Default rdlock attributes. */
|
||
extern const struct __pthread_rwlockattr __pthread_default_rwlockattr;
|
||
|
||
/* Default condition attributes. */
|
||
extern const struct __pthread_condattr __pthread_default_condattr;
|
||
|
||
/* Semaphore encoding.
|
||
See nptl implementation for the details. */
|
||
struct new_sem
|
||
{
|
||
#if __HAVE_64B_ATOMICS
|
||
/* The data field holds both value (in the least-significant 32 bits) and
|
||
nwaiters. */
|
||
# if __BYTE_ORDER == __LITTLE_ENDIAN
|
||
# define SEM_VALUE_OFFSET 0
|
||
# elif __BYTE_ORDER == __BIG_ENDIAN
|
||
# define SEM_VALUE_OFFSET 1
|
||
# else
|
||
# error Unsupported byte order.
|
||
# endif
|
||
# define SEM_NWAITERS_SHIFT 32
|
||
# define SEM_VALUE_MASK (~(unsigned int)0)
|
||
uint64_t data;
|
||
int pshared;
|
||
#define __SEMAPHORE_INITIALIZER(value, pshared) \
|
||
{ (value), (pshared) }
|
||
#else
|
||
# define SEM_VALUE_SHIFT 1
|
||
# define SEM_NWAITERS_MASK ((unsigned int)1)
|
||
unsigned int value;
|
||
unsigned int nwaiters;
|
||
int pshared;
|
||
#define __SEMAPHORE_INITIALIZER(value, pshared) \
|
||
{ (value) << SEM_VALUE_SHIFT, 0, (pshared) }
|
||
#endif
|
||
};
|
||
|
||
extern int __sem_waitfast (struct new_sem *isem, int definitive_result);
|
||
|
||
#endif /* pt-internal.h */
|