diff options
Diffstat (limited to 'cpukit/posix/src/mutex.c')
-rw-r--r-- | cpukit/posix/src/mutex.c | 683 |
1 files changed, 683 insertions, 0 deletions
diff --git a/cpukit/posix/src/mutex.c b/cpukit/posix/src/mutex.c new file mode 100644 index 0000000000..037791a252 --- /dev/null +++ b/cpukit/posix/src/mutex.c @@ -0,0 +1,683 @@ +/* + * $Id$ + */ + +#include <assert.h> +#include <errno.h> +#include <pthread.h> + +#include <rtems/system.h> +#include <rtems/score/coremutex.h> +#include <rtems/score/watchdog.h> +#include <rtems/score/mpci.h> +#include <rtems/posix/mutex.h> +#include <rtems/posix/priority.h> +#include <rtems/posix/time.h> + +/* + * TEMPORARY + */ + +void _POSIX_Mutex_MP_Send_process_packet ( + POSIX_Mutex_MP_Remote_operations operation, + Objects_Id mutex_id, + Objects_Name name, + Objects_Id proxy_id +) +{ + (void) POSIX_MP_NOT_IMPLEMENTED(); +} + +void _POSIX_Mutex_MP_Send_object_was_deleted ( + Thread_Control *the_proxy +) +{ + (void) POSIX_MP_NOT_IMPLEMENTED(); +} + +int _POSIX_Mutex_MP_Send_request_packet ( + POSIX_Mutex_MP_Remote_operations operation, + Objects_Id mutex_id, + boolean wait, /* XXX options */ + Watchdog_Interval timeout +) +{ + return POSIX_MP_NOT_IMPLEMENTED(); +} + +void POSIX_Threads_mutex_MP_support( + Thread_Control *the_thread, + Objects_Id id +) +{ + (void) POSIX_MP_NOT_IMPLEMENTED(); /* XXX: should never get here */ +} + +/* + * END OF TEMPORARY + */ + +/*PAGE + * + * The default mutex attributes structure. + */ + +const pthread_mutexattr_t _POSIX_Mutex_Default_attributes = { + TRUE, /* is_initialized */ + PTHREAD_PROCESS_PRIVATE, /* process_shared */ + POSIX_SCHEDULER_MAXIMUM_PRIORITY, /* prio_ceiling */ + PTHREAD_PRIO_NONE, /* protocol */ + FALSE /* recursive */ +}; + +/*PAGE + * + * _POSIX_Mutex_From_core_mutex_status + */ + +int _POSIX_Mutex_From_core_mutex_status( + CORE_mutex_Status status +) +{ + switch ( status ) { + case CORE_MUTEX_STATUS_SUCCESSFUL: + return 0; + case CORE_MUTEX_STATUS_UNSATISFIED_NOWAIT: + return EBUSY; + case CORE_MUTEX_STATUS_NESTING_NOT_ALLOWED: + return EDEADLK; + case CORE_MUTEX_STATUS_NOT_OWNER_OF_RESOURCE: + return EPERM; + case CORE_MUTEX_WAS_DELETED: + return EINVAL; + case CORE_MUTEX_TIMEOUT: + return EAGAIN; + case CORE_MUTEX_STATUS_CEILING_VIOLATED: + return EINVAL; + default: + break; + } + assert( 0 ); + return 0; +} + +/*PAGE + * + * _POSIX_Mutex_Manager_initialization + * + * This routine initializes all mutex manager related data structures. + * + * Input parameters: + * maximum_mutexes - maximum configured mutexes + * + * Output parameters: NONE + */ + +void _POSIX_Mutex_Manager_initialization( + unsigned32 maximum_mutexes +) +{ + _Objects_Initialize_information( + &_POSIX_Mutex_Information, + OBJECTS_POSIX_MUTEXES, + TRUE, + maximum_mutexes, + sizeof( POSIX_Mutex_Control ), + FALSE, + 0, + FALSE + ); +} + +/*PAGE + * + * 11.3.1 Mutex Initialization Attributes, P1003.1c/Draft 10, p. 81 + */ + +int pthread_mutexattr_init( + pthread_mutexattr_t *attr +) +{ + if ( !attr ) + return EINVAL; + + *attr = _POSIX_Mutex_Default_attributes; + return 0; +} + +/*PAGE + * + * 11.3.1 Mutex Initialization Attributes, P1003.1c/Draft 10, p. 81 + */ + +int pthread_mutexattr_destroy( + pthread_mutexattr_t *attr +) +{ + if ( !attr || !attr->is_initialized ) + return EINVAL; + + attr->is_initialized = FALSE; + return 0; +} + +/*PAGE + * + * 11.3.1 Mutex Initialization Attributes, P1003.1c/Draft 10, p. 81 + */ + +int pthread_mutexattr_getpshared( + const pthread_mutexattr_t *attr, + int *pshared +) +{ + if ( !attr || !attr->is_initialized || !pshared ) + return EINVAL; + + *pshared = attr->process_shared; + return 0; +} + +/*PAGE + * + * 11.3.1 Mutex Initialization Attributes, P1003.1c/Draft 10, p. 81 + */ + +int pthread_mutexattr_setpshared( + pthread_mutexattr_t *attr, + int pshared +) +{ + if ( !attr || !attr->is_initialized ) + return EINVAL; + + switch ( pshared ) { + case PTHREAD_PROCESS_SHARED: + case PTHREAD_PROCESS_PRIVATE: + attr->process_shared = pshared; + return 0; + + default: + return EINVAL; + } +} + +/*PAGE + * + * 11.3.2 Initializing and Destroying a Mutex, P1003.1c/Draft 10, p. 87 + * + * NOTE: XXX Could be optimized so all the attribute error checking + * is not performed when attr is NULL. + */ + +int pthread_mutex_init( + pthread_mutex_t *mutex, + const pthread_mutexattr_t *attr +) +{ + POSIX_Mutex_Control *the_mutex; + CORE_mutex_Attributes *the_mutex_attr; + const pthread_mutexattr_t *the_attr; + CORE_mutex_Disciplines the_discipline; + register POSIX_Mutex_Control *mutex_in_use; + Objects_Locations location; + + if ( attr ) the_attr = attr; + else the_attr = &_POSIX_Mutex_Default_attributes; + + /* Check for NULL mutex */ + + if ( !mutex ) + return EINVAL; + + /* EBUSY if *mutex is a valid id */ + + mutex_in_use = _POSIX_Mutex_Get( mutex, &location ); + switch ( location ) { + case OBJECTS_ERROR: + break; + case OBJECTS_REMOTE: + case OBJECTS_LOCAL: + _Thread_Enable_dispatch(); + return EBUSY; + }; + + if ( !the_attr->is_initialized ) + return EINVAL; + + /* + * XXX: Be careful about attributes when global!!! + */ + + assert( the_attr->process_shared == PTHREAD_PROCESS_PRIVATE ); + + if ( the_attr->process_shared == PTHREAD_PROCESS_SHARED ) + return POSIX_MP_NOT_IMPLEMENTED(); + + /* + * Determine the discipline of the mutex + */ + + switch ( the_attr->protocol ) { + case PTHREAD_PRIO_NONE: + the_discipline = CORE_MUTEX_DISCIPLINES_FIFO; + break; + case PTHREAD_PRIO_INHERIT: + the_discipline = CORE_MUTEX_DISCIPLINES_PRIORITY_INHERIT; + break; + case PTHREAD_PRIO_PROTECT: + the_discipline = CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING; + break; + default: + return EINVAL; + } + + if ( !_POSIX_Priority_Is_valid( the_attr->prio_ceiling ) ) + return EINVAL; + + _Thread_Disable_dispatch(); + + the_mutex = _POSIX_Mutex_Allocate(); + + if ( !the_mutex ) { + _Thread_Enable_dispatch(); + return EAGAIN; + } + + if ( the_attr->process_shared == PTHREAD_PROCESS_SHARED && + !( _Objects_MP_Allocate_and_open( &_POSIX_Mutex_Information, 0, + the_mutex->Object.id, FALSE ) ) ) { + _POSIX_Mutex_Free( the_mutex ); + _Thread_Enable_dispatch(); + return EAGAIN; + } + + the_mutex->process_shared = the_attr->process_shared; + + the_mutex_attr = &the_mutex->Mutex.Attributes; + + the_mutex_attr->allow_nesting = the_attr->recursive; + the_mutex_attr->priority_ceiling = + _POSIX_Priority_To_core( the_attr->prio_ceiling ); + the_mutex_attr->discipline = the_discipline; + + /* + * Must be initialized to unlocked. + */ + + _CORE_mutex_Initialize( + &the_mutex->Mutex, + OBJECTS_POSIX_MUTEXES, + the_mutex_attr, + CORE_MUTEX_UNLOCKED, + NULL /* proxy_extract_callout */ + ); + + _Objects_Open( &_POSIX_Mutex_Information, &the_mutex->Object, 0 ); + + *mutex = the_mutex->Object.id; + + if ( the_attr->process_shared == PTHREAD_PROCESS_SHARED ) + _POSIX_Mutex_MP_Send_process_packet( + POSIX_MUTEX_MP_ANNOUNCE_CREATE, + the_mutex->Object.id, + 0, /* Name not used */ + 0 /* Not used */ + ); + + _Thread_Enable_dispatch(); + return 0; +} + +/*PAGE + * + * 11.3.2 Initializing and Destroying a Mutex, P1003.1c/Draft 10, p. 87 + */ + +int pthread_mutex_destroy( + pthread_mutex_t *mutex +) +{ + register POSIX_Mutex_Control *the_mutex; + Objects_Locations location; + + the_mutex = _POSIX_Mutex_Get( mutex, &location ); + switch ( location ) { + case OBJECTS_ERROR: + return EINVAL; + case OBJECTS_REMOTE: + _Thread_Dispatch(); + return POSIX_MP_NOT_IMPLEMENTED(); + return EINVAL; + case OBJECTS_LOCAL: + /* + * XXX: There is an error for the mutex being locked + * or being in use by a condition variable. + */ + + if ( _CORE_mutex_Is_locked( &the_mutex->Mutex ) ) { + _Thread_Enable_dispatch(); + return EBUSY; + } + + _Objects_Close( &_POSIX_Mutex_Information, &the_mutex->Object ); + + _CORE_mutex_Flush( + &the_mutex->Mutex, + _POSIX_Mutex_MP_Send_object_was_deleted, + EINVAL + ); + + _POSIX_Mutex_Free( the_mutex ); + + if ( the_mutex->process_shared == PTHREAD_PROCESS_SHARED ) { + + _Objects_MP_Close( &_POSIX_Mutex_Information, the_mutex->Object.id ); + + _POSIX_Mutex_MP_Send_process_packet( + POSIX_MUTEX_MP_ANNOUNCE_DELETE, + the_mutex->Object.id, + 0, /* Not used */ + 0 /* Not used */ + ); + } + _Thread_Enable_dispatch(); + return 0; + } + return POSIX_BOTTOM_REACHED(); +} + +/*PAGE + * + * _POSIX_Mutex_Lock_support + * + * A support routine which implements guts of the blocking, non-blocking, and + * timed wait version of mutex lock. + */ + +int _POSIX_Mutex_Lock_support( + pthread_mutex_t *mutex, + boolean blocking, + Watchdog_Interval timeout +) +{ + register POSIX_Mutex_Control *the_mutex; + Objects_Locations location; + + the_mutex = _POSIX_Mutex_Get( mutex, &location ); + switch ( location ) { + case OBJECTS_ERROR: + return EINVAL; + case OBJECTS_REMOTE: + return _POSIX_Mutex_MP_Send_request_packet( + POSIX_MUTEX_MP_OBTAIN_REQUEST, + *mutex, + 0, /* must define the option set */ + WATCHDOG_NO_TIMEOUT + ); + case OBJECTS_LOCAL: + _CORE_mutex_Seize( + &the_mutex->Mutex, + the_mutex->Object.id, + blocking, + timeout + ); + _Thread_Enable_dispatch(); + return _POSIX_Mutex_From_core_mutex_status( + (CORE_mutex_Status) _Thread_Executing->Wait.return_code + ); + } + return POSIX_BOTTOM_REACHED(); +} + +/*PAGE + * + * 11.3.3 Locking and Unlocking a Mutex, P1003.1c/Draft 10, p. 93 + * + * NOTE: P1003.4b/D8 adds pthread_mutex_timedlock(), p. 29 + */ + +int pthread_mutex_lock( + pthread_mutex_t *mutex +) +{ + return _POSIX_Mutex_Lock_support( mutex, TRUE, THREAD_QUEUE_WAIT_FOREVER ); +} + +/*PAGE + * + * 11.3.3 Locking and Unlocking a Mutex, P1003.1c/Draft 10, p. 93 + * + * NOTE: P1003.4b/D8 adds pthread_mutex_timedlock(), p. 29 + */ + +int pthread_mutex_trylock( + pthread_mutex_t *mutex +) +{ + return _POSIX_Mutex_Lock_support( mutex, FALSE, THREAD_QUEUE_WAIT_FOREVER ); +} + +/*PAGE + * + * 11.3.3 Locking and Unlocking a Mutex, P1003.1c/Draft 10, p. 93 + * + * NOTE: P1003.4b/D8 adds pthread_mutex_timedlock(), p. 29 + */ + +int pthread_mutex_unlock( + pthread_mutex_t *mutex +) +{ + register POSIX_Mutex_Control *the_mutex; + Objects_Locations location; + CORE_mutex_Status status; + + the_mutex = _POSIX_Mutex_Get( mutex, &location ); + switch ( location ) { + case OBJECTS_ERROR: + return EINVAL; + case OBJECTS_REMOTE: + return _POSIX_Mutex_MP_Send_request_packet( + POSIX_MUTEX_MP_RELEASE_REQUEST, + *mutex, + 0, /* Not used */ + MPCI_DEFAULT_TIMEOUT + ); + case OBJECTS_LOCAL: + status = _CORE_mutex_Surrender( + &the_mutex->Mutex, + the_mutex->Object.id, + POSIX_Threads_mutex_MP_support + ); + _Thread_Enable_dispatch(); + return _POSIX_Mutex_From_core_mutex_status( status ); + break; + } + return POSIX_BOTTOM_REACHED(); +} + +/*PAGE + * + * 11.3.3 Locking and Unlocking a Mutex, P1003.1c/Draft 10, p. 93 + * + * NOTE: P1003.4b/D8 adds pthread_mutex_timedlock(), p. 29 + */ + +int pthread_mutex_timedlock( + pthread_mutex_t *mutex, + const struct timespec *timeout +) +{ + return _POSIX_Mutex_Lock_support( + mutex, + TRUE, + _POSIX_Timespec_to_interval( timeout ) + ); +} + +/*PAGE + * + * 13.6.1 Mutex Initialization Scheduling Attributes, P1003.1c/Draft 10, p. 128 + */ + +int pthread_mutexattr_setprotocol( + pthread_mutexattr_t *attr, + int protocol +) +{ + if ( !attr || !attr->is_initialized ) + return EINVAL; + + switch ( protocol ) { + case PTHREAD_PRIO_NONE: + case PTHREAD_PRIO_INHERIT: + case PTHREAD_PRIO_PROTECT: + attr->protocol = protocol; + return 0; + + default: + return EINVAL; + } +} + +/*PAGE + * + * 13.6.1 Mutex Initialization Scheduling Attributes, P1003.1c/Draft 10, p. 128 + */ + +int pthread_mutexattr_getprotocol( + const pthread_mutexattr_t *attr, + int *protocol +) +{ + if ( !attr || !attr->is_initialized || !protocol ) + return EINVAL; + + *protocol = attr->protocol; + return 0; +} + +/*PAGE + * + * 13.6.1 Mutex Initialization Scheduling Attributes, P1003.1c/Draft 10, p. 128 + */ + +int pthread_mutexattr_setprioceiling( + pthread_mutexattr_t *attr, + int prioceiling +) +{ + if ( !attr || !attr->is_initialized ) + return EINVAL; + + if ( !_POSIX_Priority_Is_valid( prioceiling ) ) + return EINVAL; + + attr->prio_ceiling = prioceiling; + return 0; +} + +/*PAGE + * + * 13.6.1 Mutex Initialization Scheduling Attributes, P1003.1c/Draft 10, p. 128 + */ + +int pthread_mutexattr_getprioceiling( + const pthread_mutexattr_t *attr, + int *prioceiling +) +{ + if ( !attr || !attr->is_initialized || !prioceiling ) + return EINVAL; + + *prioceiling = attr->prio_ceiling; + return 0; +} + +/*PAGE + * + * 13.6.2 Change the Priority Ceiling of a Mutex, P1003.1c/Draft 10, p. 131 + */ + +int pthread_mutex_setprioceiling( + pthread_mutex_t *mutex, + int prioceiling, + int *old_ceiling +) +{ + register POSIX_Mutex_Control *the_mutex; + Objects_Locations location; + Priority_Control the_priority; + int status; + + if ( !old_ceiling ) + return EINVAL; + + if ( !_POSIX_Priority_Is_valid( prioceiling ) ) + return EINVAL; + + the_priority = _POSIX_Priority_To_core( prioceiling ); + + /* + * Must acquire the mutex before we can change it's ceiling + */ + + status = pthread_mutex_lock( mutex ); + if ( status ) + return status; + + the_mutex = _POSIX_Mutex_Get( mutex, &location ); + switch ( location ) { + case OBJECTS_ERROR: + return EINVAL; /* impossible to get here */ + case OBJECTS_REMOTE: + /* XXX It feels questionable to set the ceiling on a remote mutex. */ + return EINVAL; + case OBJECTS_LOCAL: + *old_ceiling = _POSIX_Priority_From_core( + the_mutex->Mutex.Attributes.priority_ceiling + ); + the_mutex->Mutex.Attributes.priority_ceiling = the_priority; + _CORE_mutex_Surrender( + &the_mutex->Mutex, + the_mutex->Object.id, + POSIX_Threads_mutex_MP_support + ); + _Thread_Enable_dispatch(); + return 0; + } + return POSIX_BOTTOM_REACHED(); +} + +/*PAGE + * + * 13.6.2 Change the Priority Ceiling of a Mutex, P1003.1c/Draft 10, p. 131 + */ + +int pthread_mutex_getprioceiling( + pthread_mutex_t *mutex, + int *prioceiling +) +{ + register POSIX_Mutex_Control *the_mutex; + Objects_Locations location; + + if ( !prioceiling ) + return EINVAL; + + the_mutex = _POSIX_Mutex_Get( mutex, &location ); + switch ( location ) { + case OBJECTS_ERROR: + return EINVAL; + case OBJECTS_REMOTE: + return POSIX_MP_NOT_IMPLEMENTED(); /* XXX feels questionable */ + case OBJECTS_LOCAL: + *prioceiling = _POSIX_Priority_From_core( + the_mutex->Mutex.Attributes.priority_ceiling + ); + _Thread_Enable_dispatch(); + return 0; + } + return POSIX_BOTTOM_REACHED(); +} |