Move the priority change due to priority interitance to the thread queue
enqueue operation to simplify the locking on SMP configurations.
Update #2412.
Update #2556.
Update #2765.
---
cpukit/score/include/rtems/score/coremuteximpl.h | 3 +
cpukit/score/include/rtems/score/threadimpl.h | 31 ----------
cpukit/score/include/rtems/score/threadq.h | 9 ++-
cpukit/score/include/rtems/score/threadqimpl.h | 23 +++++++
cpukit/score/src/coremutexseize.c | 4 +-
cpukit/score/src/mutex.c | 3 +-
cpukit/score/src/threadchangepriority.c | 34 -----------
cpukit/score/src/threadqenqueue.c | 8 ++-
cpukit/score/src/threadqops.c | 78 +++++++++++++++++++++++-
9 files changed, 116 insertions(+), 77 deletions(-)
diff --git a/cpukit/score/include/rtems/score/coremuteximpl.h
b/cpukit/score/include/rtems/score/coremuteximpl.h
index 339834b..f48524a 100644
--- a/cpukit/score/include/rtems/score/coremuteximpl.h
+++ b/cpukit/score/include/rtems/score/coremuteximpl.h
@@ -36,6 +36,9 @@ extern "C" {
#define CORE_MUTEX_TQ_OPERATIONS &_Thread_queue_Operations_priority
+#define CORE_MUTEX_TQ_PRIORITY_INHERIT_OPERATIONS \
+ &_Thread_queue_Operations_priority_inherit
+
RTEMS_INLINE_ROUTINE void _CORE_mutex_Initialize(
CORE_mutex_Control *the_mutex
)
diff --git a/cpukit/score/include/rtems/score/threadimpl.h
b/cpukit/score/include/rtems/score/threadimpl.h
index 5323e2c..92968a2 100644
--- a/cpukit/score/include/rtems/score/threadimpl.h
+++ b/cpukit/score/include/rtems/score/threadimpl.h
@@ -512,37 +512,6 @@ void _Thread_Raise_priority(
);
/**
- * @brief Inherit the priority of a thread.
- *
- * It changes the current priority of the inheritor thread to the current
priority
- * of the ancestor thread if it is higher than the current priority of the
inheritor
- * thread. In this case the inheritor thread is appended to its new priority
group
- * in its scheduler instance.
- *
- * On SMP configurations, the priority is changed to PRIORITY_PSEUDO_ISR in
- * case the own schedulers of the inheritor and ancestor thread differ
(priority
- * boosting).
- *
- * @param[in] inheritor The thread to inherit the priority.
- * @param[in] ancestor The thread to bequeath its priority to the inheritor
- * thread.
- */
-#if defined(RTEMS_SMP)
-void _Thread_Inherit_priority(
- Thread_Control *inheritor,
- Thread_Control *ancestor
-);
-#else
-RTEMS_INLINE_ROUTINE void _Thread_Inherit_priority(
- Thread_Control *inheritor,
- Thread_Control *ancestor
-)
-{
- _Thread_Raise_priority( inheritor, ancestor->current_priority );
-}
-#endif
-
-/**
* @brief Sets the current to the real priority of a thread.
*
* Sets the priority restore hint to false.
diff --git a/cpukit/score/include/rtems/score/threadq.h
b/cpukit/score/include/rtems/score/threadq.h
index b3b8fec..75aab20 100644
--- a/cpukit/score/include/rtems/score/threadq.h
+++ b/cpukit/score/include/rtems/score/threadq.h
@@ -43,6 +43,8 @@ extern "C" {
typedef struct _Thread_Control Thread_Control;
+typedef struct Thread_queue_Path Thread_queue_Path;
+
#if defined(RTEMS_MULTIPROCESSING)
/**
* @brief Multiprocessing (MP) support callout for thread queue operations.
@@ -239,6 +241,10 @@ typedef void ( *Thread_queue_Priority_change_operation )(
/**
* @brief Thread queue enqueue operation.
*
+ * A potential thread to update the priority due to priority inheritance is
+ * returned via the thread queue path. This thread is handed over to
+ * _Thread_Update_priority().
+ *
* @param[in] queue The actual thread queue.
* @param[in] the_thread The thread to enqueue on the queue.
*
@@ -246,7 +252,8 @@ typedef void ( *Thread_queue_Priority_change_operation )(
*/
typedef void ( *Thread_queue_Enqueue_operation )(
Thread_queue_Queue *queue,
- Thread_Control *the_thread
+ Thread_Control *the_thread,
+ Thread_queue_Path *path
);
/**
diff --git a/cpukit/score/include/rtems/score/threadqimpl.h
b/cpukit/score/include/rtems/score/threadqimpl.h
index 2d396cb..1502b09 100644
--- a/cpukit/score/include/rtems/score/threadqimpl.h
+++ b/cpukit/score/include/rtems/score/threadqimpl.h
@@ -36,6 +36,27 @@ extern "C" {
/**@{*/
/**
+ * @brief Representation of a thread queue path from a start thread queue to
+ * the terminal thread queue.
+ *
+ * The start thread queue is determined by the object on which a thread intends
+ * to block. The terminal thread queue is the thread queue reachable via
+ * thread queue links those owner is not blocked on a thread queue. The thread
+ * queue links are determined by the thread queue owner and thread wait queue
+ * relationships.
+ */
+struct Thread_queue_Path {
+ /**
+ * @brief A potential thread to update the priority via
+ * _Thread_Update_priority().
+ *
+ * This thread is determined by thread queues which support priority
+ * inheritance.
+ */
+ Thread_Control *update_priority;
+};
+
+/**
* @brief Thread queue with a layout compatible to struct _Thread_queue_Queue
* defined in Newlib <sys/lock.h>.
*/
@@ -888,6 +909,8 @@ extern const Thread_queue_Operations
_Thread_queue_Operations_FIFO;
extern const Thread_queue_Operations _Thread_queue_Operations_priority;
+extern const Thread_queue_Operations _Thread_queue_Operations_priority_inherit;
+
/**@}*/
#ifdef __cplusplus
diff --git a/cpukit/score/src/coremutexseize.c
b/cpukit/score/src/coremutexseize.c
index c468c07..dacb274 100644
--- a/cpukit/score/src/coremutexseize.c
+++ b/cpukit/score/src/coremutexseize.c
@@ -54,8 +54,6 @@ Status_Control _CORE_mutex_Seize_slow(
_CORE_mutex_Release( the_mutex, queue_context );
#endif
- _Thread_Inherit_priority( owner, executing );
-
#if defined(RTEMS_SMP)
_Thread_queue_Context_set_expected_level( queue_context, 1 );
#else
@@ -66,7 +64,7 @@ Status_Control _CORE_mutex_Seize_slow(
_Thread_queue_Enqueue_critical(
&the_mutex->Wait_queue.Queue,
- CORE_MUTEX_TQ_OPERATIONS,
+ CORE_MUTEX_TQ_PRIORITY_INHERIT_OPERATIONS,
executing,
STATES_WAITING_FOR_MUTEX,
queue_context
diff --git a/cpukit/score/src/mutex.c b/cpukit/score/src/mutex.c
index 4b95262..12a4f29 100644
--- a/cpukit/score/src/mutex.c
+++ b/cpukit/score/src/mutex.c
@@ -26,7 +26,7 @@
#include <rtems/score/threadqimpl.h>
#include <rtems/score/todimpl.h>
-#define MUTEX_TQ_OPERATIONS &_Thread_queue_Operations_priority
+#define MUTEX_TQ_OPERATIONS &_Thread_queue_Operations_priority_inherit
typedef struct {
Thread_queue_Syslock_queue Queue;
@@ -107,7 +107,6 @@ static void _Mutex_Acquire_slow(
Thread_queue_Context *queue_context
)
{
- _Thread_Inherit_priority( owner, executing );
_Thread_queue_Context_set_expected_level( queue_context, 1 );
_Thread_queue_Enqueue_critical(
&mutex->Queue.Queue,
diff --git a/cpukit/score/src/threadchangepriority.c
b/cpukit/score/src/threadchangepriority.c
index d895ee6..e3cf4a1 100644
--- a/cpukit/score/src/threadchangepriority.c
+++ b/cpukit/score/src/threadchangepriority.c
@@ -142,40 +142,6 @@ void _Thread_Raise_priority(
);
}
-#if defined(RTEMS_SMP)
-static bool _Thread_Inherit_priority_filter(
- Thread_Control *inheritor,
- Priority_Control *new_priority,
- void *arg
-)
-{
- Thread_Control *ancestor = arg;
-
- if ( _Scheduler_Get_own( inheritor ) == _Scheduler_Get_own( ancestor ) ) {
- *new_priority = ancestor->current_priority;
- }
-
- return _Thread_Priority_less_than(
- inheritor->current_priority,
- *new_priority
- );
-}
-
-void _Thread_Inherit_priority(
- Thread_Control *inheritor,
- Thread_Control *ancestor
-)
-{
- _Thread_Change_priority(
- inheritor,
- PRIORITY_PSEUDO_ISR,
- ancestor,
- _Thread_Inherit_priority_filter,
- false
- );
-}
-#endif
-
static bool _Thread_Restore_priority_filter(
Thread_Control *the_thread,
Priority_Control *new_priority,
diff --git a/cpukit/score/src/threadqenqueue.c
b/cpukit/score/src/threadqenqueue.c
index 1528b48..818073c 100644
--- a/cpukit/score/src/threadqenqueue.c
+++ b/cpukit/score/src/threadqenqueue.c
@@ -42,8 +42,9 @@ void _Thread_queue_Enqueue_critical(
Thread_queue_Context *queue_context
)
{
- Per_CPU_Control *cpu_self;
- bool success;
+ Thread_queue_Path path;
+ Per_CPU_Control *cpu_self;
+ bool success;
#if defined(RTEMS_MULTIPROCESSING)
if ( _Thread_MP_Is_receive( the_thread ) && the_thread->receive_packet ) {
@@ -57,7 +58,7 @@ void _Thread_queue_Enqueue_critical(
_Thread_Wait_set_queue( the_thread, queue );
_Thread_Wait_set_operations( the_thread, operations );
- ( *operations->enqueue )( queue, the_thread );
+ ( *operations->enqueue )( queue, the_thread, &path );
_Thread_Wait_flags_set( the_thread, THREAD_QUEUE_INTEND_TO_BLOCK );
cpu_self = _Thread_Dispatch_disable_critical( &queue_context->Lock_context );
@@ -124,6 +125,7 @@ void _Thread_queue_Enqueue_critical(
_Thread_Remove_timer_and_unblock( the_thread, queue );
}
+ _Thread_Update_priority( path.update_priority );
_Thread_Dispatch_enable( cpu_self );
}
diff --git a/cpukit/score/src/threadqops.c b/cpukit/score/src/threadqops.c
index 83abf0d..c288cee 100644
--- a/cpukit/score/src/threadqops.c
+++ b/cpukit/score/src/threadqops.c
@@ -39,7 +39,7 @@ static void _Thread_queue_Do_nothing_extract(
/* Do nothing */
}
-static void _Thread_queue_Queue_enqueue(
+static Thread_queue_Heads *_Thread_queue_Queue_enqueue(
Thread_queue_Queue *queue,
Thread_Control *the_thread,
void ( *initialize )( Thread_queue_Heads * ),
@@ -62,6 +62,8 @@ static void _Thread_queue_Queue_enqueue(
_Chain_Prepend_unprotected( &heads->Free_chain, &spare_heads->Free_node );
( *enqueue )( heads, the_thread );
+
+ return heads;
}
static void _Thread_queue_Queue_extract(
@@ -116,9 +118,12 @@ static void _Thread_queue_FIFO_do_extract(
static void _Thread_queue_FIFO_enqueue(
Thread_queue_Queue *queue,
- Thread_Control *the_thread
+ Thread_Control *the_thread,
+ Thread_queue_Path *path
)
{
+ path->update_priority = NULL;
+
_Thread_queue_Queue_enqueue(
queue,
the_thread,
@@ -266,9 +271,12 @@ static void _Thread_queue_Priority_do_extract(
static void _Thread_queue_Priority_enqueue(
Thread_queue_Queue *queue,
- Thread_Control *the_thread
+ Thread_Control *the_thread,
+ Thread_queue_Path *path
)
{
+ path->update_priority = NULL;
+
_Thread_queue_Queue_enqueue(
queue,
the_thread,
@@ -310,6 +318,63 @@ static Thread_Control *_Thread_queue_Priority_first(
return THREAD_RBTREE_NODE_TO_THREAD( first );
}
+static void _Thread_queue_Priority_inherit_enqueue(
+ Thread_queue_Queue *queue,
+ Thread_Control *the_thread,
+ Thread_queue_Path *path
+)
+{
+ Thread_queue_Heads *heads;
+ Thread_Control *owner;
+ Priority_Control priority;
+
+ heads = _Thread_queue_Queue_enqueue(
+ queue,
+ the_thread,
+ _Thread_queue_Priority_do_initialize,
+ _Thread_queue_Priority_do_enqueue
+ );
+
+ owner = queue->owner;
+
+#if defined(RTEMS_SMP)
+ if ( _Chain_Has_only_one_node( &heads->Heads.Fifo ) ) {
+ priority = the_thread->current_priority;
+ } else {
+ priority = _Scheduler_Map_priority(
+ _Scheduler_Get_own( the_thread ),
+ PRIORITY_PSEUDO_ISR
+ );
+ }
+#else
+ (void) heads;
+
+ priority = the_thread->current_priority;
+#endif
+
+ if ( priority < owner->current_priority ) {
+ Scheduler_Node *own_node;
+
+ path->update_priority = owner;
+
+ owner->priority_restore_hint = true;
+ _Atomic_Fence( ATOMIC_ORDER_ACQ_REL );
+
+ own_node = _Scheduler_Thread_get_own_node( owner );
+ _Scheduler_Node_set_priority( own_node, priority, false );
+
+ owner->current_priority = priority;
+
+ ( *owner->Wait.operations->priority_change )(
+ owner,
+ priority,
+ owner->Wait.queue
+ );
+ } else {
+ path->update_priority = NULL;
+ }
+}
+
#if defined(RTEMS_SMP)
void _Thread_queue_Boost_priority(
Thread_queue_Queue *queue,
@@ -359,3 +424,10 @@ const Thread_queue_Operations
_Thread_queue_Operations_priority = {
.extract = _Thread_queue_Priority_extract,
.first = _Thread_queue_Priority_first
};
+
+const Thread_queue_Operations _Thread_queue_Operations_priority_inherit = {
+ .priority_change = _Thread_queue_Priority_priority_change,
+ .enqueue = _Thread_queue_Priority_inherit_enqueue,
+ .extract = _Thread_queue_Priority_extract,
+ .first = _Thread_queue_Priority_first
+};
--
1.8.4.5
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