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Diffstat (limited to 'cpukit/score/include/rtems/score/coremutex.h')
| -rw-r--r-- | cpukit/score/include/rtems/score/coremutex.h | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/cpukit/score/include/rtems/score/coremutex.h b/cpukit/score/include/rtems/score/coremutex.h new file mode 100644 index 0000000000..9f3ad2b46d --- /dev/null +++ b/cpukit/score/include/rtems/score/coremutex.h @@ -0,0 +1,172 @@ +/* mutex.h + * + * This include file contains all the constants and structures associated + * with the Mutex Handler. A mutex is an enhanced version of the standard + * Dijkstra binary semaphore used to provide synchronization and mutual + * exclusion capabilities. + * + * COPYRIGHT (c) 1989-1997. + * On-Line Applications Research Corporation (OAR). + * Copyright assigned to U.S. Government, 1994. + * + * The license and distribution terms for this file may in + * the file LICENSE in this distribution or at + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ + +#ifndef __RTEMS_CORE_MUTEX_h +#define __RTEMS_CORE_MUTEX_h + +#ifdef __cplusplus +extern "C" { +#endif + +#include <rtems/score/thread.h> +#include <rtems/score/threadq.h> +#include <rtems/score/priority.h> +#include <rtems/score/watchdog.h> + +/* + * The following type defines the callout which the API provides + * to support global/multiprocessor operations on mutexes. + */ + +typedef void ( *CORE_mutex_API_mp_support_callout )( + Thread_Control *, + Objects_Id + ); + +/* + * Blocking disciplines for a mutex. + */ + +typedef enum { + CORE_MUTEX_DISCIPLINES_FIFO, + CORE_MUTEX_DISCIPLINES_PRIORITY, + CORE_MUTEX_DISCIPLINES_PRIORITY_INHERIT, + CORE_MUTEX_DISCIPLINES_PRIORITY_CEILING +} CORE_mutex_Disciplines; + +/* + * Mutex handler return statuses. + */ + +typedef enum { + CORE_MUTEX_STATUS_SUCCESSFUL, + CORE_MUTEX_STATUS_UNSATISFIED_NOWAIT, + CORE_MUTEX_STATUS_NESTING_NOT_ALLOWED, + CORE_MUTEX_STATUS_NOT_OWNER_OF_RESOURCE, + CORE_MUTEX_WAS_DELETED, + CORE_MUTEX_TIMEOUT, + CORE_MUTEX_STATUS_CEILING_VIOLATED +} CORE_mutex_Status; + +/* + * Locked and unlocked values + */ + +#define CORE_MUTEX_UNLOCKED 1 +#define CORE_MUTEX_LOCKED 0 + +/* + * The following defines the control block used to manage the + * attributes of each mutex. + */ + +typedef struct { + boolean allow_nesting; + CORE_mutex_Disciplines discipline; + Priority_Control priority_ceiling; +} CORE_mutex_Attributes; + +/* + * The following defines the control block used to manage each mutex. + */ + +typedef struct { + Thread_queue_Control Wait_queue; + CORE_mutex_Attributes Attributes; + unsigned32 lock; + unsigned32 nest_count; + Thread_Control *holder; + Objects_Id holder_id; +} CORE_mutex_Control; + +/* + * _CORE_mutex_Initialize + * + * DESCRIPTION: + * + * This routine initializes the mutex based on the parameters passed. + */ + +void _CORE_mutex_Initialize( + CORE_mutex_Control *the_mutex, + Objects_Classes the_class, + CORE_mutex_Attributes *the_mutex_attributes, + unsigned32 initial_lock, + Thread_queue_Extract_callout proxy_extract_callout +); + +/* + * _CORE_mutex_Seize + * + * DESCRIPTION: + * + * This routine attempts to receive a unit from the_mutex. + * If a unit is available or if the wait flag is FALSE, then the routine + * returns. Otherwise, the calling task is blocked until a unit becomes + * available. + */ + +void _CORE_mutex_Seize( + CORE_mutex_Control *the_mutex, + Objects_Id id, + boolean wait, + Watchdog_Interval timeout +); + +/* + * _CORE_mutex_Surrender + * + * DESCRIPTION: + * + * This routine frees a unit to the mutex. If a task was blocked waiting for + * a unit from this mutex, then that task will be readied and the unit + * given to that task. Otherwise, the unit will be returned to the mutex. + */ + +CORE_mutex_Status _CORE_mutex_Surrender( + CORE_mutex_Control *the_mutex, + Objects_Id id, + CORE_mutex_API_mp_support_callout api_mutex_mp_support +); + +/* + * _CORE_mutex_Flush + * + * DESCRIPTION: + * + * This routine assists in the deletion of a mutex by flushing the associated + * wait queue. + */ + +void _CORE_mutex_Flush( + CORE_mutex_Control *the_mutex, + Thread_queue_Flush_callout remote_extract_callout, + unsigned32 status +); + +#ifndef __RTEMS_APPLICATION__ +#include <rtems/score/coremutex.inl> +#endif + +#ifdef __cplusplus +} +#endif + +#endif +/* end of include file */ + |