diff options
Diffstat (limited to 'linuxthreads/sysdeps/pthread/pthread.h')
| -rw-r--r-- | linuxthreads/sysdeps/pthread/pthread.h | 38 |
1 files changed, 21 insertions, 17 deletions
diff --git a/linuxthreads/sysdeps/pthread/pthread.h b/linuxthreads/sysdeps/pthread/pthread.h index 9f5e9deef2..127e15deef 100644 --- a/linuxthreads/sysdeps/pthread/pthread.h +++ b/linuxthreads/sysdeps/pthread/pthread.h @@ -43,21 +43,24 @@ typedef unsigned long int pthread_t; /* Thread descriptors */ typedef struct _pthread_descr_struct *_pthread_descr; -/* Waiting queues (not abstract because mutexes and conditions aren't). */ -struct _pthread_queue +/* Fast locks (not abstract because mutexes and conditions aren't abstract). */ +struct _pthread_fastlock { - _pthread_descr head; /* First element, or NULL if queue empty. */ - _pthread_descr tail; /* Last element, or NULL if queue empty. */ + long status; /* "Free" or "taken" or head of waiting list */ + int spinlock; /* For compare-and-swap emulation */ }; /* Mutexes (not abstract because of PTHREAD_MUTEX_INITIALIZER). */ +/* (The layout is unnatural to maintain binary compatibility + with earlier releases of LinuxThreads.) */ + typedef struct { - int m_spinlock; /* Spin lock to guarantee mutual exclusion. */ - int m_count; /* 0 if free, > 0 if taken. */ - _pthread_descr m_owner; /* Owner of mutex (for recursive mutexes) */ - int m_kind; /* Kind of mutex */ - struct _pthread_queue m_waiting; /* Threads waiting on this mutex. */ + int m_reserved; /* Reserved for future use */ + int m_count; /* Depth of recursive locking */ + _pthread_descr m_owner; /* Owner thread (if recursive or errcheck) */ + int m_kind; /* Mutex kind: fast, recursive or errcheck */ + struct _pthread_fastlock m_lock; /* Underlying fast lock */ } pthread_mutex_t; #define PTHREAD_MUTEX_INITIALIZER \ @@ -68,21 +71,21 @@ typedef struct /* Conditions (not abstract because of PTHREAD_COND_INITIALIZER */ typedef struct { - int c_spinlock; /* Spin lock to protect the queue. */ - struct _pthread_queue c_waiting; /* Threads waiting on this condition. */ + struct _pthread_fastlock c_lock; /* Protect against concurrent access */ + _pthread_descr c_waiting; /* Threads waiting on this condition */ } pthread_cond_t; -#define PTHREAD_COND_INITIALIZER {0, {0, 0}} +#define PTHREAD_COND_INITIALIZER {{0, 0}, 0} #ifdef __USE_UNIX98 /* Read-write locks. */ typedef struct { - int rw_spinlock; /* Spin lock to guarantee mutual exclusion */ + struct _pthread_fastlock rw_lock; /* Lock to guarantee mutual exclusion */ int rw_readers; /* Number of readers */ _pthread_descr rw_writer; /* Identity of writer, or NULL if none */ - struct _pthread_queue rw_read_waiting; /* Threads waiting for reading */ - struct _pthread_queue rw_write_waiting; /* Threads waiting for writing */ + _pthread_descr rw_read_waiting; /* Threads waiting for reading */ + _pthread_descr rw_write_waiting; /* Threads waiting for writing */ int rw_kind; /* Reader/Writer preference selection */ int rw_pshared; /* Shared between processes or not */ } pthread_rwlock_t; @@ -231,7 +234,8 @@ extern int pthread_detach __P ((pthread_t __th)); /* Functions for handling attributes. */ /* Initialize thread attribute *ATTR with default attributes - (detachstate is PTHREAD_JOINABLE, scheduling policy is SCHED_OTHER). */ + (detachstate is PTHREAD_JOINABLE, scheduling policy is SCHED_OTHER, + no user-provided stack). */ extern int pthread_attr_init __P ((pthread_attr_t *__attr)); /* Destroy thread attribute *ATTR. */ @@ -288,6 +292,7 @@ extern int __pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr, size_t *__guardsize)); extern int pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr, size_t *__guardsize)); +#endif /* Set the starting address of the stack of the thread to be created. Depending on whether the stack grows up or doen the value must either @@ -317,7 +322,6 @@ extern int __pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr, size_t *__stacksize)); extern int pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr, size_t *__stacksize)); -#endif /* Functions for scheduling control. */ |