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-rw-r--r--cpukit/score/src/threadq.c837
1 files changed, 0 insertions, 837 deletions
diff --git a/cpukit/score/src/threadq.c b/cpukit/score/src/threadq.c
deleted file mode 100644
index 60ffb5db38..0000000000
--- a/cpukit/score/src/threadq.c
+++ /dev/null
@@ -1,837 +0,0 @@
-/*
- * Thread Queue Handler
- *
- *
- * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
- * On-Line Applications Research Corporation (OAR).
- * All rights assigned to U.S. Government, 1994.
- *
- * This material may be reproduced by or for the U.S. Government pursuant
- * to the copyright license under the clause at DFARS 252.227-7013. This
- * notice must appear in all copies of this file and its derivatives.
- *
- * $Id$
- */
-
-#include <rtems/system.h>
-#include <rtems/chain.h>
-#include <rtems/isr.h>
-#include <rtems/object.h>
-#include <rtems/states.h>
-#include <rtems/thread.h>
-#include <rtems/threadq.h>
-#include <rtems/tqdata.h>
-
-/*PAGE
- *
- * _Thread_queue_Initialize
- *
- * This routine initializes the specified threadq.
- *
- * Input parameters:
- * the_thread_queue - pointer to a threadq header
- * attribute_set - used to determine queueing discipline
- * state - state of waiting threads
- *
- * Output parameters: NONE
- */
-
-void _Thread_queue_Initialize(
- Thread_queue_Control *the_thread_queue,
- rtems_attribute attribute_set,
- States_Control state
-)
-{
- unsigned32 index;
-
- if ( _Attributes_Is_priority( attribute_set ) ) {
- the_thread_queue->discipline = THREAD_QUEUE_DATA_PRIORITY_DISCIPLINE;
- for( index=0 ;
- index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ;
- index++)
- _Chain_Initialize_empty( &the_thread_queue->Queues.Priority[index] );
- }
- else {
- the_thread_queue->discipline = THREAD_QUEUE_DATA_FIFO_DISCIPLINE;
- _Chain_Initialize_empty( &the_thread_queue->Queues.Fifo );
- }
-
- the_thread_queue->state = state;
-
-}
-
-/*PAGE
- *
- * _Thread_queue_Enqueue
- *
- * This routine blocks a thread, places it on a thread, and optionally
- * starts a timeout timer.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq
- * timeout - interval to wait
- *
- * Output parameters: NONE
- *
- * INTERRUPT LATENCY:
- * only case
- */
-
-void _Thread_queue_Enqueue(
- Thread_queue_Control *the_thread_queue,
- rtems_interval timeout
-)
-{
- Thread_Control *the_thread;
-
- the_thread = _Thread_Executing;
-
- if ( _Thread_MP_Is_receive( the_thread ) )
- the_thread = _Thread_MP_Allocate_proxy( the_thread_queue->state );
- else
- _Thread_Set_state( the_thread, the_thread_queue->state );
-
- if ( timeout ) {
- _Watchdog_Initialize(
- &the_thread->Timer,
- _Thread_queue_Timeout,
- the_thread->Object.id,
- NULL
- );
-
- _Watchdog_Insert_ticks(
- &the_thread->Timer,
- timeout,
- WATCHDOG_NO_ACTIVATE
- );
- }
-
- switch( the_thread_queue->discipline ) {
- case THREAD_QUEUE_DATA_FIFO_DISCIPLINE:
- _Thread_queue_Enqueue_fifo( the_thread_queue, the_thread, timeout );
- break;
- case THREAD_QUEUE_DATA_PRIORITY_DISCIPLINE:
- _Thread_queue_Enqueue_priority(
- the_thread_queue, the_thread, timeout );
- break;
- }
-}
-
-/*PAGE
- *
- * _Thread_queue_Dequeue
- *
- * This routine removes a thread from the specified threadq. If the
- * threadq discipline is RTEMS_FIFO, it unblocks a thread, and cancels its
- * timeout timer. Priority discipline is processed elsewhere.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq
- *
- * Output parameters:
- * returns - thread dequeued or NULL
- *
- * INTERRUPT LATENCY:
- * check sync
- * RTEMS_FIFO
- */
-
-Thread_Control *_Thread_queue_Dequeue(
- Thread_queue_Control *the_thread_queue
-)
-{
- Thread_Control *the_thread;
- ISR_Level level;
-
- switch ( the_thread_queue->discipline ) {
- case THREAD_QUEUE_DATA_FIFO_DISCIPLINE:
- the_thread = _Thread_queue_Dequeue_fifo( the_thread_queue );
- break;
- case THREAD_QUEUE_DATA_PRIORITY_DISCIPLINE:
- the_thread = _Thread_queue_Dequeue_priority( the_thread_queue );
- break;
- default: /* this is only to prevent warnings */
- the_thread = NULL;
- break;
- }
-
- if ( !_Thread_Is_null( the_thread ) )
- return( the_thread );
-
- _ISR_Disable( level );
- if ( the_thread_queue->sync == FALSE ) {
- _ISR_Enable( level );
- return( NULL );
- }
-
- the_thread_queue->sync = FALSE;
- _ISR_Enable( level );
- return( _Thread_Executing );
-}
-
-/*PAGE
- *
- * _Thread_queue_Extract
- *
- * This routine removes a specific thread from the specified threadq,
- * deletes any timeout, and unblocks the thread.
- *
- * Input parameters:
- * the_thread_queue - pointer to a threadq header
- * the_thread - pointer to a thread control block
- *
- * Output parameters: NONE
- *
- * INTERRUPT LATENCY: NONE
- */
-
-void _Thread_queue_Extract(
- Thread_queue_Control *the_thread_queue,
- Thread_Control *the_thread
-)
-{
- switch ( the_thread_queue->discipline ) {
- case THREAD_QUEUE_DATA_FIFO_DISCIPLINE:
- _Thread_queue_Extract_fifo( the_thread_queue, the_thread );
- break;
- case THREAD_QUEUE_DATA_PRIORITY_DISCIPLINE:
- _Thread_queue_Extract_priority( the_thread_queue, the_thread );
- break;
- }
-}
-
-/*PAGE
- *
- * _Thread_queue_Flush
- *
- * This kernel routine flushes the given thread queue.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq to be flushed
- *
- * Output parameters: NONE
- */
-
-void _Thread_queue_Flush(
- Thread_queue_Control *the_thread_queue,
- Thread_queue_Flush_callout remote_extract_callout
-)
-{
- Thread_Control *the_thread;
-
- while ( (the_thread = _Thread_queue_Dequeue( the_thread_queue )) ) {
- if ( _Objects_Is_local_id( the_thread->Object.id ) )
- the_thread->Wait.return_code = RTEMS_OBJECT_WAS_DELETED;
- else
- ( *remote_extract_callout )( the_thread );
- }
-}
-
-/*PAGE
- *
- * _Thread_queue_First
- *
- * This routines returns a pointer to the first thread on the
- * specified threadq.
- *
- * Input parameters:
- * the_thread_queue - pointer to thread queue
- *
- * Output parameters:
- * returns - first thread or NULL
- */
-
-Thread_Control *_Thread_queue_First(
- Thread_queue_Control *the_thread_queue
-)
-{
- Thread_Control *the_thread;
-
- switch ( the_thread_queue->discipline ) {
- case THREAD_QUEUE_DATA_FIFO_DISCIPLINE:
- the_thread = _Thread_queue_First_fifo( the_thread_queue );
- break;
- case THREAD_QUEUE_DATA_PRIORITY_DISCIPLINE:
- the_thread = _Thread_queue_First_priority( the_thread_queue );
- break;
- default: /* this is only to prevent warnings */
- the_thread = NULL;
- break;
- }
-
- return the_thread;
-}
-
-/*PAGE
- *
- * _Thread_queue_Timeout
- *
- * This routine processes a thread which timeouts while waiting on
- * a thread queue. It is called by the watchdog handler.
- *
- * Input parameters:
- * id - thread id
- *
- * Output parameters: NONE
- */
-
-void _Thread_queue_Timeout(
- Objects_Id id,
- void *ignored
-)
-{
- Thread_Control *the_thread;
- Objects_Locations location;
-
- the_thread = _Thread_Get( id, &location );
- switch ( location ) {
- case OBJECTS_ERROR:
- case OBJECTS_REMOTE: /* impossible */
- break;
- case OBJECTS_LOCAL:
- the_thread->Wait.return_code = RTEMS_TIMEOUT;
- _Thread_queue_Extract( the_thread->Wait.queue, the_thread );
- _Thread_Unnest_dispatch();
- break;
- }
-}
-
-/*PAGE
- *
- * _Thread_queue_Enqueue_fifo
- *
- * This routine blocks a thread, places it on a thread, and optionally
- * starts a timeout timer.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq
- * the_thread - pointer to the thread to block
- * timeout - interval to wait
- *
- * Output parameters: NONE
- *
- * INTERRUPT LATENCY:
- * only case
- */
-
-void _Thread_queue_Enqueue_fifo (
- Thread_queue_Control *the_thread_queue,
- Thread_Control *the_thread,
- rtems_interval timeout
-)
-{
- ISR_Level level;
-
- _ISR_Disable( level );
- if ( the_thread_queue->sync == TRUE ) {
- the_thread_queue->sync = FALSE;
-
- _Chain_Append_unprotected(
- &the_thread_queue->Queues.Fifo,
- &the_thread->Object.Node
- );
-
- if ( timeout != RTEMS_NO_TIMEOUT )
- _Watchdog_Activate( &the_thread->Timer );
-
- _ISR_Enable( level );
- return;
- }
-
- if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
- _ISR_Enable( level );
- _Thread_Unblock( the_thread );
- } else {
- _Watchdog_Deactivate( &the_thread->Timer );
- _ISR_Enable( level );
- (void) _Watchdog_Remove( &the_thread->Timer );
- _Thread_Unblock( the_thread );
- }
-
- if ( !_Objects_Is_local_id( the_thread->Object.id ) )
- _Thread_MP_Free_proxy( the_thread );
-
-}
-
-/*PAGE
- *
- * _Thread_queue_Dequeue_fifo
- *
- * This routine removes a thread from the specified threadq.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq
- *
- * Output parameters:
- * returns - thread dequeued or NULL
- *
- * INTERRUPT LATENCY:
- * check sync
- * RTEMS_FIFO
- */
-
-Thread_Control *_Thread_queue_Dequeue_fifo(
- Thread_queue_Control *the_thread_queue
-)
-{
- ISR_Level level;
- Thread_Control *the_thread;
-
- _ISR_Disable( level );
- if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) ) {
-
- the_thread = (Thread_Control *)
- _Chain_Get_first_unprotected( &the_thread_queue->Queues.Fifo );
-
- if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
- _ISR_Enable( level );
- _Thread_Unblock( the_thread );
- } else {
- _Watchdog_Deactivate( &the_thread->Timer );
- _ISR_Enable( level );
- (void) _Watchdog_Remove( &the_thread->Timer );
- _Thread_Unblock( the_thread );
- }
-
- if ( !_Objects_Is_local_id( the_thread->Object.id ) )
- _Thread_MP_Free_proxy( the_thread );
-
- return( the_thread );
- }
- _ISR_Enable( level );
- return( NULL );
-}
-
-/*PAGE
- *
- * _Thread_queue_Extract_fifo
- *
- * This routine removes a specific thread from the specified threadq,
- * deletes any timeout, and unblocks the thread.
- *
- * Input parameters:
- * the_thread_queue - pointer to a threadq header
- * the_thread - pointer to the thread to block
- *
- * Output parameters: NONE
- *
- * INTERRUPT LATENCY:
- * EXTRACT_FIFO
- */
-
-void _Thread_queue_Extract_fifo(
- Thread_queue_Control *the_thread_queue,
- Thread_Control *the_thread
-)
-{
- ISR_Level level;
-
- _ISR_Disable( level );
-
- if ( !_States_Is_waiting_on_thread_queue( the_thread->current_state ) ) {
- _ISR_Enable( level );
- return;
- }
-
- _Chain_Extract_unprotected( &the_thread->Object.Node );
-
- if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
- _ISR_Enable( level );
- _Thread_Unblock( the_thread );
- } else {
- _Watchdog_Deactivate( &the_thread->Timer );
- _ISR_Enable( level );
- (void) _Watchdog_Remove( &the_thread->Timer );
- _Thread_Unblock( the_thread );
- }
-
- if ( !_Objects_Is_local_id( the_thread->Object.id ) )
- _Thread_MP_Free_proxy( the_thread );
-}
-
-/*PAGE
- *
- * _Thread_queue_First_fifo
- *
- * This routines returns a pointer to the first thread on the
- * specified threadq.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq
- *
- * Output parameters:
- * returns - first thread or NULL
- */
-
-Thread_Control *_Thread_queue_First_fifo(
- Thread_queue_Control *the_thread_queue
-)
-{
- if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) )
- return (Thread_Control *) the_thread_queue->Queues.Fifo.first;
-
- return NULL;
-}
-
-/*PAGE
- *
- * _Thread_queue_Enqueue_priority
- *
- * This routine blocks a thread, places it on a thread, and optionally
- * starts a timeout timer.
- *
- * Input parameters:
- * the_thread_queue - pointer to threadq
- * thread - thread to insert
- * timeout - timeout interval in ticks
- *
- * Output parameters: NONE
- *
- * INTERRUPT LATENCY:
- * forward less than
- * forward equal
- */
-
-void _Thread_queue_Enqueue_priority(
- Thread_queue_Control *the_thread_queue,
- Thread_Control *the_thread,
- rtems_interval timeout
-)
-{
- rtems_task_priority search_priority;
- Thread_Control *search_thread;
- ISR_Level level;
- Chain_Control *header;
- unsigned32 header_index;
- Chain_Node *the_node;
- Chain_Node *next_node;
- Chain_Node *previous_node;
- Chain_Node *search_node;
- rtems_task_priority priority;
- States_Control block_state;
-
- _Chain_Initialize_empty( &the_thread->Wait.Block2n );
-
- priority = the_thread->current_priority;
- header_index = _Thread_queue_Header_number( priority );
- header = &the_thread_queue->Queues.Priority[ header_index ];
- block_state = the_thread_queue->state;
-
- if ( _Thread_queue_Is_reverse_search( priority ) )
- goto restart_reverse_search;
-
-restart_forward_search:
- search_priority = RTEMS_MINIMUM_PRIORITY - 1;
- _ISR_Disable( level );
- search_thread = (Thread_Control *) header->first;
- while ( !_Chain_Is_tail( header, (Chain_Node *)search_thread ) ) {
- search_priority = search_thread->current_priority;
- if ( priority <= search_priority )
- break;
-
-#if ( CPU_UNROLL_ENQUEUE_PRIORITY == TRUE )
- search_thread = (Thread_Control *) search_thread->Object.Node.next;
- if ( _Chain_Is_tail( header, (Chain_Node *)search_thread ) )
- break;
- search_priority = search_thread->current_priority;
- if ( priority <= search_priority )
- break;
-#endif
- _ISR_Flash( level );
- if ( !_States_Are_set( search_thread->current_state, block_state) ) {
- _ISR_Enable( level );
- goto restart_forward_search;
- }
- search_thread =
- (Thread_Control *)search_thread->Object.Node.next;
- }
- if ( the_thread_queue->sync == FALSE )
- goto syncronize;
-
- the_thread_queue->sync = FALSE;
- if ( timeout != RTEMS_NO_TIMEOUT )
- _Watchdog_Activate( &the_thread->Timer );
-
- if ( priority == search_priority )
- goto equal_priority;
-
- search_node = (Chain_Node *) search_thread;
- previous_node = search_node->previous;
- the_node = (Chain_Node *) the_thread;
-
- the_node->next = search_node;
- the_node->previous = previous_node;
- previous_node->next = the_node;
- search_node->previous = the_node;
- _ISR_Enable( level );
- return;
-
-restart_reverse_search:
- search_priority = RTEMS_MAXIMUM_PRIORITY + 1;
-
- _ISR_Disable( level );
- search_thread = (Thread_Control *) header->last;
- while ( !_Chain_Is_head( header, (Chain_Node *)search_thread ) ) {
- search_priority = search_thread->current_priority;
- if ( priority >= search_priority )
- break;
-#if ( CPU_UNROLL_ENQUEUE_PRIORITY == TRUE )
- search_thread = (Thread_Control *) search_thread->Object.Node.previous;
- if ( _Chain_Is_head( header, (Chain_Node *)search_thread ) )
- break;
- search_priority = search_thread->current_priority;
- if ( priority >= search_priority )
- break;
-#endif
- _ISR_Flash( level );
- if ( !_States_Are_set( search_thread->current_state, block_state) ) {
- _ISR_Enable( level );
- goto restart_reverse_search;
- }
- search_thread = (Thread_Control *)
- search_thread->Object.Node.previous;
- }
- if ( !the_thread_queue->sync )
- goto syncronize;
-
- the_thread_queue->sync = FALSE;
- if ( timeout != RTEMS_NO_TIMEOUT )
- _Watchdog_Activate( &the_thread->Timer );
-
- if ( priority == search_priority )
- goto equal_priority;
-
- search_node = (Chain_Node *) search_thread;
- next_node = search_node->next;
- the_node = (Chain_Node *) the_thread;
-
- the_node->next = next_node;
- the_node->previous = search_node;
- search_node->next = the_node;
- next_node->previous = the_node;
- _ISR_Enable( level );
- return;
-
-equal_priority: /* add at end of priority group */
- search_node = _Chain_Tail( &search_thread->Wait.Block2n );
- previous_node = search_node->previous;
- the_node = (Chain_Node *) the_thread;
-
- the_node->next = search_node;
- the_node->previous = previous_node;
- previous_node->next = the_node;
- search_node->previous = the_node;
- _ISR_Enable( level );
- return;
-
-syncronize:
- if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
- _ISR_Enable( level );
- _Thread_Unblock( the_thread );
- } else {
- _Watchdog_Deactivate( &the_thread->Timer );
- _ISR_Enable( level );
- (void) _Watchdog_Remove( &the_thread->Timer );
- _Thread_Unblock( the_thread );
- }
- if ( !_Objects_Is_local_id( the_thread->Object.id ) )
- _Thread_MP_Free_proxy( the_thread );
-}
-
-/*PAGE
- *
- * _Thread_queue_Dequeue_priority
- *
- * This routine removes a thread from the specified RTEMS_PRIORITY based
- * threadq, unblocks it, and cancels its timeout timer.
- *
- * Input parameters:
- * the_thread_queue - pointer to thread queue
- *
- * Output parameters:
- * returns - thread dequeued or NULL
- *
- * INTERRUPT LATENCY:
- * only case
- */
-
-Thread_Control *_Thread_queue_Dequeue_priority(
- Thread_queue_Control *the_thread_queue
-)
-{
- unsigned32 index;
- ISR_Level level;
- Thread_Control *the_thread;
- Thread_Control *new_first_thread;
- Chain_Node *new_first_node;
- Chain_Node *new_second_node;
- Chain_Node *last_node;
- Chain_Node *next_node;
- Chain_Node *previous_node;
-
- for( index=0 ;
- index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ;
- index++ ) {
- _ISR_Disable( level );
- if ( !_Chain_Is_empty( &the_thread_queue->Queues.Priority[ index ] ) ) {
- the_thread = (Thread_Control *)
- the_thread_queue->Queues.Priority[ index ].first;
- goto dequeue;
- }
- _ISR_Enable( level );
- }
- return NULL;
-
-dequeue:
- new_first_node = the_thread->Wait.Block2n.first;
- new_first_thread = (Thread_Control *) new_first_node;
- next_node = the_thread->Object.Node.next;
- previous_node = the_thread->Object.Node.previous;
-
- if ( !_Chain_Is_empty( &the_thread->Wait.Block2n ) ) {
- last_node = the_thread->Wait.Block2n.last;
- new_second_node = new_first_node->next;
-
- previous_node->next = new_first_node;
- next_node->previous = new_first_node;
- new_first_node->next = next_node;
- new_first_node->previous = previous_node;
-
- if ( !_Chain_Has_only_one_node( &the_thread->Wait.Block2n ) ) {
- /* > two threads on 2-n */
- new_second_node->previous =
- _Chain_Head( &new_first_thread->Wait.Block2n );
-
- new_first_thread->Wait.Block2n.first = new_second_node;
- new_first_thread->Wait.Block2n.last = last_node;
-
- last_node->next = _Chain_Tail( &new_first_thread->Wait.Block2n );
- }
- } else {
- previous_node->next = next_node;
- next_node->previous = previous_node;
- }
-
- if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
- _ISR_Enable( level );
- _Thread_Unblock( the_thread );
- } else {
- _Watchdog_Deactivate( &the_thread->Timer );
- _ISR_Enable( level );
- (void) _Watchdog_Remove( &the_thread->Timer );
- _Thread_Unblock( the_thread );
- }
-
- if ( !_Objects_Is_local_id( the_thread->Object.id ) )
- _Thread_MP_Free_proxy( the_thread );
- return( the_thread );
-}
-
-/*PAGE
- *
- * _Thread_queue_Extract_priority
- *
- * This routine removes a specific thread from the specified threadq,
- * deletes any timeout, and unblocks the thread.
- *
- * Input parameters:
- * the_thread_queue - pointer to a threadq header
- * the_thread - pointer to a thread control block
- *
- * Output parameters: NONE
- *
- * INTERRUPT LATENCY:
- * EXTRACT_PRIORITY
- */
-
-void _Thread_queue_Extract_priority(
- Thread_queue_Control *the_thread_queue,
- Thread_Control *the_thread
-)
-{
- ISR_Level level;
- Chain_Node *the_node;
- Chain_Node *next_node;
- Chain_Node *previous_node;
- Thread_Control *new_first_thread;
- Chain_Node *new_first_node;
- Chain_Node *new_second_node;
- Chain_Node *last_node;
-
- the_node = (Chain_Node *) the_thread;
- _ISR_Disable( level );
- if ( _States_Is_waiting_on_thread_queue( the_thread->current_state ) ) {
- next_node = the_node->next;
- previous_node = the_node->previous;
-
- if ( !_Chain_Is_empty( &the_thread->Wait.Block2n ) ) {
- new_first_node = the_thread->Wait.Block2n.first;
- new_first_thread = (Thread_Control *) new_first_node;
- last_node = the_thread->Wait.Block2n.last;
- new_second_node = new_first_node->next;
-
- previous_node->next = new_first_node;
- next_node->previous = new_first_node;
- new_first_node->next = next_node;
- new_first_node->previous = previous_node;
-
- if ( !_Chain_Has_only_one_node( &the_thread->Wait.Block2n ) ) {
- /* > two threads on 2-n */
- new_second_node->previous =
- _Chain_Head( &new_first_thread->Wait.Block2n );
- new_first_thread->Wait.Block2n.first = new_second_node;
-
- new_first_thread->Wait.Block2n.last = last_node;
- last_node->next = _Chain_Tail( &new_first_thread->Wait.Block2n );
- }
- } else {
- previous_node->next = next_node;
- next_node->previous = previous_node;
- }
-
- if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
- _ISR_Enable( level );
- _Thread_Unblock( the_thread );
- } else {
- _Watchdog_Deactivate( &the_thread->Timer );
- _ISR_Enable( level );
- (void) _Watchdog_Remove( &the_thread->Timer );
- _Thread_Unblock( the_thread );
- }
-
- if ( !_Objects_Is_local_id( the_thread->Object.id ) )
- _Thread_MP_Free_proxy( the_thread );
- }
- else
- _ISR_Enable( level );
-}
-
-/*PAGE
- *
- * _Thread_queue_First_priority
- *
- * This routines returns a pointer to the first thread on the
- * specified threadq.
- *
- * Input parameters:
- * the_thread_queue - pointer to thread queue
- *
- * Output parameters:
- * returns - first thread or NULL
- */
-
-Thread_Control *_Thread_queue_First_priority (
- Thread_queue_Control *the_thread_queue
-)
-{
- unsigned32 index;
-
- for( index=0 ;
- index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ;
- index++ ) {
- if ( !_Chain_Is_empty( &the_thread_queue->Queues.Priority[ index ] ) )
- return (Thread_Control *)
- the_thread_queue->Queues.Priority[ index ].first;
- }
- return NULL;
-}