diff options
author | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2021-08-31 11:03:57 +0200 |
---|---|---|
committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2021-09-01 20:24:57 +0200 |
commit | d9249c9bffe4238e3853996d1f0758d9f55fbe67 (patch) | |
tree | 95e948656a5ca4c639cda76d0c34728d7af98fe0 /cpukit/include | |
parent | score: Fix priority discipline handling (diff) | |
download | rtems-d9249c9bffe4238e3853996d1f0758d9f55fbe67.tar.bz2 |
score: Fix blocking message queue receive
In order to ensure FIFO fairness across schedulers, the thread queue
surrender operation must be used to dequeue a thread from the thread
queue. The thread queue extract operation is intended for timeouts.
Add _Thread_queue_Resume() which may be used to make extracted or
surrendered threads ready again.
Remove the now unused _Thread_queue_Extract_critical() function.
Close #4509.
Diffstat (limited to 'cpukit/include')
-rw-r--r-- | cpukit/include/rtems/score/coremsgimpl.h | 20 | ||||
-rw-r--r-- | cpukit/include/rtems/score/threadqimpl.h | 59 |
2 files changed, 25 insertions, 54 deletions
diff --git a/cpukit/include/rtems/score/coremsgimpl.h b/cpukit/include/rtems/score/coremsgimpl.h index 161cf8f124..7f01769010 100644 --- a/cpukit/include/rtems/score/coremsgimpl.h +++ b/cpukit/include/rtems/score/coremsgimpl.h @@ -616,7 +616,8 @@ RTEMS_INLINE_ROUTINE Thread_Control *_CORE_message_queue_Dequeue_receiver( Thread_queue_Context *queue_context ) { - Thread_Control *the_thread; + Thread_queue_Heads *heads; + Thread_Control *the_thread; /* * If there are pending messages, then there can't be threads @@ -634,14 +635,18 @@ RTEMS_INLINE_ROUTINE Thread_Control *_CORE_message_queue_Dequeue_receiver( * There must be no pending messages if there is a thread waiting to * receive a message. */ - the_thread = _Thread_queue_First_locked( - &the_message_queue->Wait_queue, - the_message_queue->operations - ); - if ( the_thread == NULL ) { + heads = the_message_queue->Wait_queue.Queue.heads; + if ( heads == NULL ) { return NULL; } + the_thread = ( *the_message_queue->operations->surrender )( + &the_message_queue->Wait_queue.Queue, + heads, + NULL, + queue_context + ); + *(size_t *) the_thread->Wait.return_argument = size; the_thread->Wait.count = (uint32_t) submit_type; @@ -651,9 +656,8 @@ RTEMS_INLINE_ROUTINE Thread_Control *_CORE_message_queue_Dequeue_receiver( size ); - _Thread_queue_Extract_critical( + _Thread_queue_Resume( &the_message_queue->Wait_queue.Queue, - the_message_queue->operations, the_thread, queue_context ); diff --git a/cpukit/include/rtems/score/threadqimpl.h b/cpukit/include/rtems/score/threadqimpl.h index 2465fc4499..0a24d2da3b 100644 --- a/cpukit/include/rtems/score/threadqimpl.h +++ b/cpukit/include/rtems/score/threadqimpl.h @@ -975,56 +975,23 @@ void _Thread_queue_Unblock_critical( ); /** - * @brief Extracts the thread from the thread queue and unblocks it. + * @brief Resumes the extracted or surrendered thread. * - * The caller must be the owner of the thread queue lock. This function will - * release the thread queue lock and restore the default thread lock. Thread - * dispatching is disabled before the thread queue lock is released and an - * unblock is necessary. Thread dispatching is enabled once the sequence to - * unblock the thread is complete. This makes it possible to use the thread - * queue lock to protect the state of objects embedding the thread queue and - * directly enter _Thread_queue_Extract_critical() to finalize an operation in - * case a waiting thread exists. - * - * @code - * #include <rtems/score/threadqimpl.h> - * - * typedef struct { - * Thread_queue_Control Queue; - * Thread_Control *owner; - * } Mutex; + * This function makes the thread ready again. If necessary, the thread is + * unblocked and its thread timer removed. * - * void _Mutex_Release( Mutex *mutex ) - * { - * Thread_queue_Context queue_context; - * Thread_Control *first; - * - * _Thread_queue_Context_initialize( &queue_context, NULL ); - * _Thread_queue_Acquire( &mutex->Queue, queue_context ); - * - * first = _Thread_queue_First_locked( &mutex->Queue ); - * mutex->owner = first; - * - * if ( first != NULL ) { - * _Thread_queue_Extract_critical( - * &mutex->Queue.Queue, - * mutex->Queue.operations, - * first, - * &queue_context - * ); - * } - * @endcode + * The thread shall have been extracted from the thread queue or surrendered by + * the thread queue right before the call to this function. The caller shall + * be the owner of the thread queue lock. * - * @param queue The actual thread queue. - * @param operations The thread queue operations. - * @param[in, out] the_thread The thread to extract. - * @param[in, out] queue_context The thread queue context of the lock acquire. + * @param queue is the actual thread queue. + * @param[in, out] the_thread is the thread to make ready and unblock. + * @param[in, out] queue_context is the thread queue context. */ -void _Thread_queue_Extract_critical( - Thread_queue_Queue *queue, - const Thread_queue_Operations *operations, - Thread_Control *the_thread, - Thread_queue_Context *queue_context +void _Thread_queue_Resume( + Thread_queue_Queue *queue, + Thread_Control *the_thread, + Thread_queue_Context *queue_context ); /** |