freebsd-dev/include/pthread.h

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/*
* Copyright (c) 1993, 1994 by Chris Provenzano, proven@mit.edu
* Copyright (c) 1995-1998 by John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Chris Provenzano.
* 4. The name of Chris Provenzano may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL CHRIS PROVENZANO BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
1999-08-27 23:45:13 +00:00
* $FreeBSD$
*/
#ifndef _PTHREAD_H_
#define _PTHREAD_H_
/*
* Header files.
*/
#include <sys/cdefs.h>
#include <sys/_pthreadtypes.h>
#include <machine/_limits.h>
#include <machine/_types.h>
#include <sys/_sigset.h>
o Runnable threads are now maintained in priority queues. The implementation requires two things: 1.) The priority queues must be protected during insertion and removal of threads. Since the kernel scheduler must modify the priority queues, a spinlock for protection cannot be used. The functions _thread_kern_sched_defer() and _thread_kern_sched_undefer() were added to {un}defer kernel scheduler activation. 2.) A thread (active) priority change can be performed only when the thread is removed from the priority queue. The implementation uses a threads active priority when inserting it into the queue. A by-product is that thread switches are much faster. A separate queue is used for waiting and/or blocked threads, and it is searched at most 2 times in the kernel scheduler when there are active threads. It should be possible to reduce this to once by combining polling of threads waiting on I/O with the loop that looks for timed out threads and the minimum timeout value. o Functions to defer kernel scheduler activation were added. These are _thread_kern_sched_defer() and _thread_kern_sched_undefer() and may be called recursively. These routines do not block the scheduling signal, but latch its occurrence. The signal handler will not call the kernel scheduler when the running thread has deferred scheduling, but it will be called when running thread undefers scheduling. o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING. All the POSIX routines required by this should now be implemented. One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required to be defined by including pthread.h. These defines are currently in sched.h. I modified pthread.h to include sched.h but don't know if this is the proper thing to do. o Added support for priority protection and inheritence mutexes. This allows definition of _POSIX_THREAD_PRIO_PROTECT and _POSIX_THREAD_PRIO_INHERIT. o Added additional error checks required by POSIX for mutexes and condition variables. o Provided a wrapper for sigpending which is marked as a hidden syscall. o Added a non-portable function as a debugging aid to allow an application to monitor thread context switches. An application can install a routine that gets called everytime a thread (explicitly created by the application) gets context switched. The routine gets passed the pthread IDs of the threads that are being switched in and out. I found this useful, but we can get rid of it if you want. Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
#include <sched.h>
#include <time.h>
__NULLABILITY_PRAGMA_PUSH
/*
* Run-time invariant values:
*/
#define PTHREAD_DESTRUCTOR_ITERATIONS 4
#define PTHREAD_KEYS_MAX 256
#define PTHREAD_STACK_MIN __MINSIGSTKSZ
#define PTHREAD_THREADS_MAX __ULONG_MAX
#define PTHREAD_BARRIER_SERIAL_THREAD -1
/*
* Flags for threads and thread attributes.
*/
#define PTHREAD_DETACHED 0x1
#define PTHREAD_SCOPE_SYSTEM 0x2
#define PTHREAD_INHERIT_SCHED 0x4
#define PTHREAD_NOFLOAT 0x8
#define PTHREAD_CREATE_DETACHED PTHREAD_DETACHED
#define PTHREAD_CREATE_JOINABLE 0
#define PTHREAD_SCOPE_PROCESS 0
#define PTHREAD_EXPLICIT_SCHED 0
/*
* Values for process shared/private attributes.
*/
#define PTHREAD_PROCESS_PRIVATE 0
#define PTHREAD_PROCESS_SHARED 1
/*
* Flags for cancelling threads
*/
#define PTHREAD_CANCEL_ENABLE 0
#define PTHREAD_CANCEL_DISABLE 1
#define PTHREAD_CANCEL_DEFERRED 0
#define PTHREAD_CANCEL_ASYNCHRONOUS 2
#define PTHREAD_CANCELED ((void *) 1)
/*
* Flags for once initialization.
*/
#define PTHREAD_NEEDS_INIT 0
#define PTHREAD_DONE_INIT 1
/*
* Static once initialization values.
*/
#define PTHREAD_ONCE_INIT { PTHREAD_NEEDS_INIT, NULL }
/*
* Static initialization values.
*/
#define PTHREAD_MUTEX_INITIALIZER NULL
#define PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP ((pthread_mutex_t)1)
#define PTHREAD_COND_INITIALIZER NULL
#define PTHREAD_RWLOCK_INITIALIZER NULL
/*
* Default attribute arguments (draft 4, deprecated).
*/
#ifndef PTHREAD_KERNEL
#define pthread_condattr_default NULL
#define pthread_mutexattr_default NULL
#define pthread_attr_default NULL
#endif
#define PTHREAD_PRIO_NONE 0
#define PTHREAD_PRIO_INHERIT 1
#define PTHREAD_PRIO_PROTECT 2
o Runnable threads are now maintained in priority queues. The implementation requires two things: 1.) The priority queues must be protected during insertion and removal of threads. Since the kernel scheduler must modify the priority queues, a spinlock for protection cannot be used. The functions _thread_kern_sched_defer() and _thread_kern_sched_undefer() were added to {un}defer kernel scheduler activation. 2.) A thread (active) priority change can be performed only when the thread is removed from the priority queue. The implementation uses a threads active priority when inserting it into the queue. A by-product is that thread switches are much faster. A separate queue is used for waiting and/or blocked threads, and it is searched at most 2 times in the kernel scheduler when there are active threads. It should be possible to reduce this to once by combining polling of threads waiting on I/O with the loop that looks for timed out threads and the minimum timeout value. o Functions to defer kernel scheduler activation were added. These are _thread_kern_sched_defer() and _thread_kern_sched_undefer() and may be called recursively. These routines do not block the scheduling signal, but latch its occurrence. The signal handler will not call the kernel scheduler when the running thread has deferred scheduling, but it will be called when running thread undefers scheduling. o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING. All the POSIX routines required by this should now be implemented. One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required to be defined by including pthread.h. These defines are currently in sched.h. I modified pthread.h to include sched.h but don't know if this is the proper thing to do. o Added support for priority protection and inheritence mutexes. This allows definition of _POSIX_THREAD_PRIO_PROTECT and _POSIX_THREAD_PRIO_INHERIT. o Added additional error checks required by POSIX for mutexes and condition variables. o Provided a wrapper for sigpending which is marked as a hidden syscall. o Added a non-portable function as a debugging aid to allow an application to monitor thread context switches. An application can install a routine that gets called everytime a thread (explicitly created by the application) gets context switched. The routine gets passed the pthread IDs of the threads that are being switched in and out. I found this useful, but we can get rid of it if you want. Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
/*
* Mutex types (Single UNIX Specification, Version 2, 1997).
*
* Note that a mutex attribute with one of the following types:
*
* PTHREAD_MUTEX_NORMAL
* PTHREAD_MUTEX_RECURSIVE
*
* will deviate from POSIX specified semantics.
*/
enum pthread_mutextype {
o Runnable threads are now maintained in priority queues. The implementation requires two things: 1.) The priority queues must be protected during insertion and removal of threads. Since the kernel scheduler must modify the priority queues, a spinlock for protection cannot be used. The functions _thread_kern_sched_defer() and _thread_kern_sched_undefer() were added to {un}defer kernel scheduler activation. 2.) A thread (active) priority change can be performed only when the thread is removed from the priority queue. The implementation uses a threads active priority when inserting it into the queue. A by-product is that thread switches are much faster. A separate queue is used for waiting and/or blocked threads, and it is searched at most 2 times in the kernel scheduler when there are active threads. It should be possible to reduce this to once by combining polling of threads waiting on I/O with the loop that looks for timed out threads and the minimum timeout value. o Functions to defer kernel scheduler activation were added. These are _thread_kern_sched_defer() and _thread_kern_sched_undefer() and may be called recursively. These routines do not block the scheduling signal, but latch its occurrence. The signal handler will not call the kernel scheduler when the running thread has deferred scheduling, but it will be called when running thread undefers scheduling. o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING. All the POSIX routines required by this should now be implemented. One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required to be defined by including pthread.h. These defines are currently in sched.h. I modified pthread.h to include sched.h but don't know if this is the proper thing to do. o Added support for priority protection and inheritence mutexes. This allows definition of _POSIX_THREAD_PRIO_PROTECT and _POSIX_THREAD_PRIO_INHERIT. o Added additional error checks required by POSIX for mutexes and condition variables. o Provided a wrapper for sigpending which is marked as a hidden syscall. o Added a non-portable function as a debugging aid to allow an application to monitor thread context switches. An application can install a routine that gets called everytime a thread (explicitly created by the application) gets context switched. The routine gets passed the pthread IDs of the threads that are being switched in and out. I found this useful, but we can get rid of it if you want. Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
PTHREAD_MUTEX_ERRORCHECK = 1, /* Default POSIX mutex */
PTHREAD_MUTEX_RECURSIVE = 2, /* Recursive mutex */
PTHREAD_MUTEX_NORMAL = 3, /* No error checking */
PTHREAD_MUTEX_ADAPTIVE_NP = 4, /* Adaptive mutex, spins briefly before blocking on lock */
PTHREAD_MUTEX_TYPE_MAX
};
#define PTHREAD_MUTEX_DEFAULT PTHREAD_MUTEX_ERRORCHECK
Add implementation of robust mutexes, hopefully close enough to the intention of the POSIX IEEE Std 1003.1TM-2008/Cor 1-2013. A robust mutex is guaranteed to be cleared by the system upon either thread or process owner termination while the mutex is held. The next mutex locker is then notified about inconsistent mutex state and can execute (or abandon) corrective actions. The patch mostly consists of small changes here and there, adding neccessary checks for the inconsistent and abandoned conditions into existing paths. Additionally, the thread exit handler was extended to iterate over the userspace-maintained list of owned robust mutexes, unlocking and marking as terminated each of them. The list of owned robust mutexes cannot be maintained atomically synchronous with the mutex lock state (it is possible in kernel, but is too expensive). Instead, for the duration of lock or unlock operation, the current mutex is remembered in a special slot that is also checked by the kernel at thread termination. Kernel must be aware about the per-thread location of the heads of robust mutex lists and the current active mutex slot. When a thread touches a robust mutex for the first time, a new umtx op syscall is issued which informs about location of lists heads. The umtx sleep queues for PP and PI mutexes are split between non-robust and robust. Somewhat unrelated changes in the patch: 1. Style. 2. The fix for proper tdfind() call use in umtxq_sleep_pi() for shared pi mutexes. 3. Removal of the userspace struct pthread_mutex m_owner field. 4. The sysctl kern.ipc.umtx_vnode_persistent is added, which controls the lifetime of the shared mutex associated with a vnode' page. Reviewed by: jilles (previous version, supposedly the objection was fixed) Discussed with: brooks, Martin Simmons <martin@lispworks.com> (some aspects) Tested by: pho Sponsored by: The FreeBSD Foundation
2016-05-17 09:56:22 +00:00
#define PTHREAD_MUTEX_STALLED 0
#define PTHREAD_MUTEX_ROBUST 1
struct _pthread_cleanup_info {
__uintptr_t pthread_cleanup_pad[8];
};
/*
* Thread function prototype definitions:
*/
__BEGIN_DECLS
int pthread_atfork(void (*)(void), void (*)(void), void (*)(void));
int pthread_attr_destroy(pthread_attr_t * _Nonnull);
int pthread_attr_getstack(
const pthread_attr_t * _Nonnull __restrict,
void ** _Nonnull __restrict,
size_t * _Nonnull __restrict);
int pthread_attr_getstacksize(const pthread_attr_t * _Nonnull,
size_t * _Nonnull);
int pthread_attr_getguardsize(const pthread_attr_t * _Nonnull,
size_t * _Nonnull);
int pthread_attr_getstackaddr(const pthread_attr_t *, void **);
int pthread_attr_getdetachstate(const pthread_attr_t * _Nonnull,
int * _Nonnull);
int pthread_attr_init(pthread_attr_t * _Nonnull);
int pthread_attr_setstacksize(pthread_attr_t * _Nonnull, size_t);
int pthread_attr_setguardsize(pthread_attr_t * _Nonnull, size_t);
int pthread_attr_setstack(pthread_attr_t * _Nonnull, void *,
size_t);
int pthread_attr_setstackaddr(pthread_attr_t *, void *);
int pthread_attr_setdetachstate(pthread_attr_t * _Nonnull, int);
int pthread_barrier_destroy(pthread_barrier_t * _Nonnull);
int pthread_barrier_init(pthread_barrier_t * _Nonnull,
const pthread_barrierattr_t *, unsigned);
int pthread_barrier_wait(pthread_barrier_t * _Nonnull);
int pthread_barrierattr_destroy(pthread_barrierattr_t * _Nonnull);
int pthread_barrierattr_getpshared(
const pthread_barrierattr_t * _Nonnull, int * _Nonnull);
int pthread_barrierattr_init(pthread_barrierattr_t * _Nonnull);
int pthread_barrierattr_setpshared(pthread_barrierattr_t * _Nonnull,
int);
#define pthread_cleanup_push(cleanup_routine, cleanup_arg) \
{ \
struct _pthread_cleanup_info __cleanup_info__; \
__pthread_cleanup_push_imp(cleanup_routine, cleanup_arg,\
&__cleanup_info__); \
{
#define pthread_cleanup_pop(execute) \
(void)0; \
} \
__pthread_cleanup_pop_imp(execute); \
}
int pthread_condattr_destroy(pthread_condattr_t * _Nonnull);
int pthread_condattr_getclock(const pthread_condattr_t * _Nonnull,
clockid_t * _Nonnull);
int pthread_condattr_getpshared(const pthread_condattr_t * _Nonnull,
int * _Nonnull);
int pthread_condattr_init(pthread_condattr_t * _Nonnull);
int pthread_condattr_setclock(pthread_condattr_t * _Nonnull,
clockid_t);
int pthread_condattr_setpshared(pthread_condattr_t * _Nonnull, int);
int pthread_cond_broadcast(pthread_cond_t * _Nonnull);
int pthread_cond_destroy(pthread_cond_t * _Nonnull);
int pthread_cond_init(pthread_cond_t * _Nonnull,
const pthread_condattr_t *);
int pthread_cond_signal(pthread_cond_t * _Nonnull);
int pthread_cond_timedwait(pthread_cond_t * _Nonnull,
pthread_mutex_t * _Nonnull __mutex,
const struct timespec * _Nonnull)
__requires_exclusive(*__mutex);
int pthread_cond_wait(pthread_cond_t * _Nonnull,
pthread_mutex_t * _Nonnull __mutex)
__requires_exclusive(*__mutex);
int pthread_create(pthread_t * _Nonnull, const pthread_attr_t *,
void *(* _Nonnull) (void *), void *);
int pthread_detach(pthread_t);
int pthread_equal(pthread_t, pthread_t);
void pthread_exit(void *) __dead2;
void *pthread_getspecific(pthread_key_t);
int pthread_getcpuclockid(pthread_t, clockid_t * _Nonnull);
int pthread_join(pthread_t, void **);
int pthread_key_create(pthread_key_t * _Nonnull,
void (*) (void *));
int pthread_key_delete(pthread_key_t);
int pthread_mutexattr_init(pthread_mutexattr_t * _Nonnull);
int pthread_mutexattr_destroy(pthread_mutexattr_t * _Nonnull);
int pthread_mutexattr_getpshared(
const pthread_mutexattr_t * _Nonnull, int * _Nonnull);
int pthread_mutexattr_gettype(pthread_mutexattr_t * _Nonnull,
int * _Nonnull);
int pthread_mutexattr_settype(pthread_mutexattr_t * _Nonnull, int);
int pthread_mutexattr_setpshared(pthread_mutexattr_t * _Nonnull,
int);
int pthread_mutex_consistent(pthread_mutex_t * _Nonnull __mutex)
__requires_exclusive(*__mutex);
int pthread_mutex_destroy(pthread_mutex_t * _Nonnull __mutex)
__requires_unlocked(*__mutex);
int pthread_mutex_init(pthread_mutex_t * _Nonnull __mutex,
const pthread_mutexattr_t *)
__requires_unlocked(*__mutex);
int pthread_mutex_lock(pthread_mutex_t * _Nonnull __mutex)
__locks_exclusive(*__mutex);
int pthread_mutex_trylock(pthread_mutex_t * _Nonnull __mutex)
__trylocks_exclusive(0, *__mutex);
int pthread_mutex_timedlock(pthread_mutex_t * _Nonnull __mutex,
const struct timespec * _Nonnull)
__trylocks_exclusive(0, *__mutex);
int pthread_mutex_unlock(pthread_mutex_t * _Nonnull __mutex)
__unlocks(*__mutex);
int pthread_once(pthread_once_t * _Nonnull,
void (* _Nonnull) (void));
int pthread_rwlock_destroy(pthread_rwlock_t * _Nonnull __rwlock)
__requires_unlocked(*__rwlock);
int pthread_rwlock_init(pthread_rwlock_t * _Nonnull __rwlock,
const pthread_rwlockattr_t *)
__requires_unlocked(*__rwlock);
int pthread_rwlock_rdlock(pthread_rwlock_t * _Nonnull __rwlock)
__locks_shared(*__rwlock);
int pthread_rwlock_timedrdlock(pthread_rwlock_t * _Nonnull __rwlock,
const struct timespec * _Nonnull)
__trylocks_shared(0, *__rwlock);
int pthread_rwlock_timedwrlock(pthread_rwlock_t * _Nonnull __rwlock,
const struct timespec * _Nonnull)
__trylocks_exclusive(0, *__rwlock);
int pthread_rwlock_tryrdlock(pthread_rwlock_t * _Nonnull __rwlock)
__trylocks_shared(0, *__rwlock);
int pthread_rwlock_trywrlock(pthread_rwlock_t * _Nonnull __rwlock)
__trylocks_exclusive(0, *__rwlock);
int pthread_rwlock_unlock(pthread_rwlock_t * _Nonnull __rwlock)
__unlocks(*__rwlock);
int pthread_rwlock_wrlock(pthread_rwlock_t * _Nonnull __rwlock)
__locks_exclusive(*__rwlock);
int pthread_rwlockattr_destroy(pthread_rwlockattr_t * _Nonnull);
int pthread_rwlockattr_getkind_np(
const pthread_rwlockattr_t * _Nonnull, int *);
int pthread_rwlockattr_getpshared(
const pthread_rwlockattr_t * _Nonnull, int * _Nonnull);
int pthread_rwlockattr_init(pthread_rwlockattr_t * _Nonnull);
int pthread_rwlockattr_setkind_np(pthread_rwlockattr_t * _Nonnull,
int);
int pthread_rwlockattr_setpshared(pthread_rwlockattr_t * _Nonnull,
int);
pthread_t pthread_self(void);
int pthread_setspecific(pthread_key_t, const void *);
int pthread_spin_init(pthread_spinlock_t * _Nonnull __spin, int)
__requires_unlocked(*__spin);
int pthread_spin_destroy(pthread_spinlock_t * _Nonnull __spin)
__requires_unlocked(*__spin);
int pthread_spin_lock(pthread_spinlock_t * _Nonnull __spin)
__locks_exclusive(*__spin);
int pthread_spin_trylock(pthread_spinlock_t * _Nonnull __spin)
__trylocks_exclusive(0, *__spin);
int pthread_spin_unlock(pthread_spinlock_t * _Nonnull __spin)
__unlocks(*__spin);
int pthread_cancel(pthread_t);
int pthread_setcancelstate(int, int *);
int pthread_setcanceltype(int, int *);
void pthread_testcancel(void);
#if __BSD_VISIBLE
int pthread_getprio(pthread_t);
int pthread_setprio(pthread_t, int);
void pthread_yield(void);
#endif
o Runnable threads are now maintained in priority queues. The implementation requires two things: 1.) The priority queues must be protected during insertion and removal of threads. Since the kernel scheduler must modify the priority queues, a spinlock for protection cannot be used. The functions _thread_kern_sched_defer() and _thread_kern_sched_undefer() were added to {un}defer kernel scheduler activation. 2.) A thread (active) priority change can be performed only when the thread is removed from the priority queue. The implementation uses a threads active priority when inserting it into the queue. A by-product is that thread switches are much faster. A separate queue is used for waiting and/or blocked threads, and it is searched at most 2 times in the kernel scheduler when there are active threads. It should be possible to reduce this to once by combining polling of threads waiting on I/O with the loop that looks for timed out threads and the minimum timeout value. o Functions to defer kernel scheduler activation were added. These are _thread_kern_sched_defer() and _thread_kern_sched_undefer() and may be called recursively. These routines do not block the scheduling signal, but latch its occurrence. The signal handler will not call the kernel scheduler when the running thread has deferred scheduling, but it will be called when running thread undefers scheduling. o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING. All the POSIX routines required by this should now be implemented. One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required to be defined by including pthread.h. These defines are currently in sched.h. I modified pthread.h to include sched.h but don't know if this is the proper thing to do. o Added support for priority protection and inheritence mutexes. This allows definition of _POSIX_THREAD_PRIO_PROTECT and _POSIX_THREAD_PRIO_INHERIT. o Added additional error checks required by POSIX for mutexes and condition variables. o Provided a wrapper for sigpending which is marked as a hidden syscall. o Added a non-portable function as a debugging aid to allow an application to monitor thread context switches. An application can install a routine that gets called everytime a thread (explicitly created by the application) gets context switched. The routine gets passed the pthread IDs of the threads that are being switched in and out. I found this useful, but we can get rid of it if you want. Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
int pthread_mutexattr_getprioceiling(pthread_mutexattr_t *, int *);
int pthread_mutexattr_setprioceiling(pthread_mutexattr_t *, int);
int pthread_mutex_getprioceiling(pthread_mutex_t *, int *);
int pthread_mutex_setprioceiling(pthread_mutex_t *, int, int *);
o Runnable threads are now maintained in priority queues. The implementation requires two things: 1.) The priority queues must be protected during insertion and removal of threads. Since the kernel scheduler must modify the priority queues, a spinlock for protection cannot be used. The functions _thread_kern_sched_defer() and _thread_kern_sched_undefer() were added to {un}defer kernel scheduler activation. 2.) A thread (active) priority change can be performed only when the thread is removed from the priority queue. The implementation uses a threads active priority when inserting it into the queue. A by-product is that thread switches are much faster. A separate queue is used for waiting and/or blocked threads, and it is searched at most 2 times in the kernel scheduler when there are active threads. It should be possible to reduce this to once by combining polling of threads waiting on I/O with the loop that looks for timed out threads and the minimum timeout value. o Functions to defer kernel scheduler activation were added. These are _thread_kern_sched_defer() and _thread_kern_sched_undefer() and may be called recursively. These routines do not block the scheduling signal, but latch its occurrence. The signal handler will not call the kernel scheduler when the running thread has deferred scheduling, but it will be called when running thread undefers scheduling. o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING. All the POSIX routines required by this should now be implemented. One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required to be defined by including pthread.h. These defines are currently in sched.h. I modified pthread.h to include sched.h but don't know if this is the proper thing to do. o Added support for priority protection and inheritence mutexes. This allows definition of _POSIX_THREAD_PRIO_PROTECT and _POSIX_THREAD_PRIO_INHERIT. o Added additional error checks required by POSIX for mutexes and condition variables. o Provided a wrapper for sigpending which is marked as a hidden syscall. o Added a non-portable function as a debugging aid to allow an application to monitor thread context switches. An application can install a routine that gets called everytime a thread (explicitly created by the application) gets context switched. The routine gets passed the pthread IDs of the threads that are being switched in and out. I found this useful, but we can get rid of it if you want. Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
int pthread_mutexattr_getprotocol(pthread_mutexattr_t *, int *);
int pthread_mutexattr_setprotocol(pthread_mutexattr_t *, int);
o Runnable threads are now maintained in priority queues. The implementation requires two things: 1.) The priority queues must be protected during insertion and removal of threads. Since the kernel scheduler must modify the priority queues, a spinlock for protection cannot be used. The functions _thread_kern_sched_defer() and _thread_kern_sched_undefer() were added to {un}defer kernel scheduler activation. 2.) A thread (active) priority change can be performed only when the thread is removed from the priority queue. The implementation uses a threads active priority when inserting it into the queue. A by-product is that thread switches are much faster. A separate queue is used for waiting and/or blocked threads, and it is searched at most 2 times in the kernel scheduler when there are active threads. It should be possible to reduce this to once by combining polling of threads waiting on I/O with the loop that looks for timed out threads and the minimum timeout value. o Functions to defer kernel scheduler activation were added. These are _thread_kern_sched_defer() and _thread_kern_sched_undefer() and may be called recursively. These routines do not block the scheduling signal, but latch its occurrence. The signal handler will not call the kernel scheduler when the running thread has deferred scheduling, but it will be called when running thread undefers scheduling. o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING. All the POSIX routines required by this should now be implemented. One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required to be defined by including pthread.h. These defines are currently in sched.h. I modified pthread.h to include sched.h but don't know if this is the proper thing to do. o Added support for priority protection and inheritence mutexes. This allows definition of _POSIX_THREAD_PRIO_PROTECT and _POSIX_THREAD_PRIO_INHERIT. o Added additional error checks required by POSIX for mutexes and condition variables. o Provided a wrapper for sigpending which is marked as a hidden syscall. o Added a non-portable function as a debugging aid to allow an application to monitor thread context switches. An application can install a routine that gets called everytime a thread (explicitly created by the application) gets context switched. The routine gets passed the pthread IDs of the threads that are being switched in and out. I found this useful, but we can get rid of it if you want. Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
int pthread_mutexattr_getrobust(
pthread_mutexattr_t * _Nonnull __restrict,
int * _Nonnull __restrict);
int pthread_mutexattr_setrobust(pthread_mutexattr_t * _Nonnull,
int);
Add implementation of robust mutexes, hopefully close enough to the intention of the POSIX IEEE Std 1003.1TM-2008/Cor 1-2013. A robust mutex is guaranteed to be cleared by the system upon either thread or process owner termination while the mutex is held. The next mutex locker is then notified about inconsistent mutex state and can execute (or abandon) corrective actions. The patch mostly consists of small changes here and there, adding neccessary checks for the inconsistent and abandoned conditions into existing paths. Additionally, the thread exit handler was extended to iterate over the userspace-maintained list of owned robust mutexes, unlocking and marking as terminated each of them. The list of owned robust mutexes cannot be maintained atomically synchronous with the mutex lock state (it is possible in kernel, but is too expensive). Instead, for the duration of lock or unlock operation, the current mutex is remembered in a special slot that is also checked by the kernel at thread termination. Kernel must be aware about the per-thread location of the heads of robust mutex lists and the current active mutex slot. When a thread touches a robust mutex for the first time, a new umtx op syscall is issued which informs about location of lists heads. The umtx sleep queues for PP and PI mutexes are split between non-robust and robust. Somewhat unrelated changes in the patch: 1. Style. 2. The fix for proper tdfind() call use in umtxq_sleep_pi() for shared pi mutexes. 3. Removal of the userspace struct pthread_mutex m_owner field. 4. The sysctl kern.ipc.umtx_vnode_persistent is added, which controls the lifetime of the shared mutex associated with a vnode' page. Reviewed by: jilles (previous version, supposedly the objection was fixed) Discussed with: brooks, Martin Simmons <martin@lispworks.com> (some aspects) Tested by: pho Sponsored by: The FreeBSD Foundation
2016-05-17 09:56:22 +00:00
int pthread_attr_getinheritsched(const pthread_attr_t *, int *);
int pthread_attr_getschedparam(const pthread_attr_t * _Nonnull,
struct sched_param * _Nonnull);
int pthread_attr_getschedpolicy(const pthread_attr_t * _Nonnull,
int * _Nonnull);
int pthread_attr_getscope(const pthread_attr_t * _Nonnull,
int * _Nonnull);
int pthread_attr_setinheritsched(pthread_attr_t *, int);
int pthread_attr_setschedparam(pthread_attr_t * _Nonnull,
const struct sched_param * _Nonnull);
int pthread_attr_setschedpolicy(pthread_attr_t * _Nonnull, int);
int pthread_attr_setscope(pthread_attr_t * _Nonnull, int);
int pthread_getschedparam(pthread_t pthread, int * _Nonnull,
struct sched_param * _Nonnull);
int pthread_setschedparam(pthread_t, int,
const struct sched_param * _Nonnull);
#if __XSI_VISIBLE
int pthread_getconcurrency(void);
int pthread_setconcurrency(int);
#endif
void __pthread_cleanup_push_imp(void (*)(void *), void *,
struct _pthread_cleanup_info *);
void __pthread_cleanup_pop_imp(int);
__END_DECLS
__NULLABILITY_PRAGMA_POP
2017-02-16 20:28:30 +00:00
#endif /* !_PTHREAD_H_ */