diff options
Diffstat (limited to 'cpukit/score/src/coremsgflushsupp.c')
-rw-r--r-- | cpukit/score/src/coremsgflushsupp.c | 84 |
1 files changed, 0 insertions, 84 deletions
diff --git a/cpukit/score/src/coremsgflushsupp.c b/cpukit/score/src/coremsgflushsupp.c deleted file mode 100644 index 041972fb9c..0000000000 --- a/cpukit/score/src/coremsgflushsupp.c +++ /dev/null @@ -1,84 +0,0 @@ -/** - * @file - * - * @brief Flush Messages Support Routine - * - * @ingroup ScoreMessageQueue - */ - -/* - * COPYRIGHT (c) 1989-1999. - * On-Line Applications Research Corporation (OAR). - * - * The license and distribution terms for this file may be - * found in the file LICENSE in this distribution or at - * http://www.rtems.org/license/LICENSE. - */ - -#if HAVE_CONFIG_H -#include "config.h" -#endif - -#include <rtems/system.h> -#include <rtems/score/chain.h> -#include <rtems/score/isr.h> -#include <rtems/score/coremsgimpl.h> -#include <rtems/score/thread.h> -#include <rtems/score/wkspace.h> - -uint32_t _CORE_message_queue_Flush_support( - CORE_message_queue_Control *the_message_queue -) -{ - ISR_Level level; - Chain_Node *inactive_head; - Chain_Node *inactive_first; - Chain_Node *message_queue_first; - Chain_Node *message_queue_last; - uint32_t count; - - /* - * Currently, RTEMS supports no API that has both flush and blocking - * sends. Thus, this routine assumes that there are no senders - * blocked waiting to send messages. In the event, that an API is - * added that can flush a message queue when threads are blocked - * waiting to send, there are two basic behaviors envisioned: - * - * (1) The thread queue of pending senders is a logical extension - * of the pending message queue. In this case, it should be - * flushed using the _Thread_queue_Flush() service with a status - * such as CORE_MESSAGE_QUEUE_SENDER_FLUSHED (which currently does - * not exist). This can be implemented without changing the "big-O" - * of the message flushing part of the routine. - * - * (2) Only the actual messages queued should be purged. In this case, - * the blocked sender threads must be allowed to send their messages. - * In this case, the implementation will be forced to individually - * dequeue the senders and queue their messages. This will force - * this routine to have "big O(n)" where n is the number of blocked - * senders. If there are more messages pending than senders blocked, - * then the existing flush code can be used to dispose of the remaining - * pending messages. - * - * For now, though, we are very happy to have a small routine with - * fixed execution time that only deals with pending messages. - */ - - _ISR_Disable( level ); - inactive_head = _Chain_Head( &the_message_queue->Inactive_messages ); - inactive_first = inactive_head->next; - message_queue_first = _Chain_First( &the_message_queue->Pending_messages ); - message_queue_last = _Chain_Last( &the_message_queue->Pending_messages ); - - inactive_head->next = message_queue_first; - message_queue_last->next = inactive_first; - inactive_first->previous = message_queue_last; - message_queue_first->previous = inactive_head; - - _Chain_Initialize_empty( &the_message_queue->Pending_messages ); - - count = the_message_queue->number_of_pending_messages; - the_message_queue->number_of_pending_messages = 0; - _ISR_Enable( level ); - return count; -} |