rtems: Add rtems_task_get_priority()

Update #2556.
Update #2784.

6 files changed, 172 insertions, 0 deletions

diff --git a/cpukit/rtems/Makefile.am b/cpukit/rtems/Makefile.am
index 0a452c8121..4be426620c 100644
--- a/cpukit/rtems/Makefile.am
+++ b/cpukit/rtems/Makefile.am
@@ -88,6 +88,7 @@ librtems_a_SOURCES += src/tasks.c
 librtems_a_SOURCES += src/taskcreate.c
 librtems_a_SOURCES += src/taskdelete.c
 librtems_a_SOURCES += src/taskgetaffinity.c
+librtems_a_SOURCES += src/taskgetpriority.c
 librtems_a_SOURCES += src/taskgetscheduler.c
 librtems_a_SOURCES += src/taskident.c
 librtems_a_SOURCES += src/taskinitusers.c
diff --git a/cpukit/rtems/include/rtems/rtems/tasks.h b/cpukit/rtems/include/rtems/rtems/tasks.h
index e690e60557..0eaaeca4a3 100644
--- a/cpukit/rtems/include/rtems/rtems/tasks.h
+++ b/cpukit/rtems/include/rtems/rtems/tasks.h
@@ -320,6 +320,35 @@ rtems_status_code rtems_task_set_priority(
 );
 
 /**
+ * @brief Gets the current priority of the specified task with respect to the
+ * specified scheduler instance.
+ *
+ * The current priority reflects temporary priority adjustments due to locking
+ * protocols, the rate-monotonic period objects on some schedulers and other
+ * mechanisms.
+ *
+ * @param[in] task_id Identifier of the task.  Use @ref RTEMS_SELF to select
+ *   the executing task.
+ * @param[in] scheduler_id Identifier of the scheduler instance.
+ * @param[out] priority Returns the current priority of the specified task with
+ *   respect to the specified scheduler instance.
+ *
+ * @retval RTEMS_SUCCESSFUL Successful operation.
+ * @retval RTEMS_ILLEGAL_ON_REMOTE_OBJECT Directive is illegal on remote tasks.
+ * @retval RTEMS_INVALID_ADDRESS The priority parameter is @c NULL.
+ * @retval RTEMS_INVALID_ID Invalid task or scheduler identifier.
+ * @retval RTEMS_NOT_DEFINED The task has no priority within the specified
+ *   scheduler instance.  This error is only possible on SMP configurations.
+ *
+ * @see rtems_scheduler_ident().
+ */
+rtems_status_code rtems_task_get_priority(
+  rtems_id             task_id,
+  rtems_id             scheduler_id,
+  rtems_task_priority *priority
+);
+
+/**
  *  @brief RTEMS Start Task
  *
  *  RTEMS Task Manager
diff --git a/cpukit/rtems/src/taskgetpriority.c b/cpukit/rtems/src/taskgetpriority.c
new file mode 100644
index 0000000000..b6800e2133
--- /dev/null
+++ b/cpukit/rtems/src/taskgetpriority.c
@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2016 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * 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/rtems/tasksimpl.h>
+#include <rtems/score/schedulerimpl.h>
+#include <rtems/score/threadimpl.h>
+
+rtems_status_code rtems_task_get_priority(
+  rtems_id             task_id,
+  rtems_id             scheduler_id,
+  rtems_task_priority *priority
+)
+{
+  Thread_Control          *the_thread;
+  Thread_queue_Context     queue_context;
+  const Scheduler_Control *scheduler;
+  const Scheduler_Node    *scheduler_node;
+  Priority_Control         core_priority;
+
+  if ( priority == NULL ) {
+    return RTEMS_INVALID_ADDRESS;
+  }
+
+  if ( !_Scheduler_Get_by_id( scheduler_id, &scheduler ) ) {
+    return RTEMS_INVALID_ID;
+  }
+
+  _Thread_queue_Context_initialize( &queue_context );
+  the_thread = _Thread_Get( task_id,
+    &queue_context.Lock_context.Lock_context
+  );
+
+  if ( the_thread == NULL ) {
+#if defined(RTEMS_MULTIPROCESSING)
+    if ( _Thread_MP_Is_remote( task_id ) ) {
+      return RTEMS_ILLEGAL_ON_REMOTE_OBJECT;
+    }
+#endif
+
+    return RTEMS_INVALID_ID;
+  }
+
+  scheduler_node = _Thread_Scheduler_get_node_by_index(
+     the_thread,
+    _Scheduler_Get_index( scheduler )
+  );
+
+  _Thread_Wait_acquire_critical( the_thread, &queue_context );
+
+#if defined(RTEMS_SMP)
+  if ( _Priority_Is_empty( &scheduler_node->Wait.Priority ) ) {
+    _Thread_Wait_release( the_thread, &queue_context );
+    return RTEMS_NOT_DEFINED;
+  }
+#endif
+
+  core_priority = _Priority_Get_priority( &scheduler_node->Wait.Priority );
+
+  _Thread_Wait_release( the_thread, &queue_context );
+  *priority = _RTEMS_Priority_From_core( scheduler, core_priority );
+  return RTEMS_SUCCESSFUL;
+}
diff --git a/testsuites/smptests/smpmutex01/init.c b/testsuites/smptests/smpmutex01/init.c
index c6b1b48c9d..d88b7b8113 100644
--- a/testsuites/smptests/smpmutex01/init.c
+++ b/testsuites/smptests/smpmutex01/init.c
@@ -57,6 +57,21 @@ typedef struct {
 
 static test_context test_instance;
 
+static void test_task_get_priority_not_defined(test_context *ctx)
+{
+  rtems_status_code sc;
+  rtems_id scheduler_id;
+  rtems_task_priority priority;
+
+  sc = rtems_scheduler_ident(SCHED_B, &scheduler_id);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+
+  priority = 0;
+  sc = rtems_task_get_priority(RTEMS_SELF, scheduler_id, &priority);
+  rtems_test_assert(sc == RTEMS_NOT_DEFINED);
+  rtems_test_assert(priority == 0);
+}
+
 static void start_task(
   test_context *ctx,
   task_id id,
@@ -340,6 +355,7 @@ static void test(void)
   test_context *ctx = &test_instance;
 
   test_init(ctx);
+  test_task_get_priority_not_defined(ctx);
   test_simple_inheritance(ctx);
   test_dequeue_order_one_scheduler_instance(ctx);
   test_simple_boosting(ctx);
diff --git a/testsuites/sptests/spscheduler01/init.c b/testsuites/sptests/spscheduler01/init.c
index bb0c16def6..d6213c6bcc 100644
--- a/testsuites/sptests/spscheduler01/init.c
+++ b/testsuites/sptests/spscheduler01/init.c
@@ -411,6 +411,44 @@ static void test_scheduler_get_processors(void)
 #endif /* defined(__RTEMS_HAVE_SYS_CPUSET_H__) */
 }
 
+static void test_task_get_priority(void)
+{
+  rtems_status_code sc;
+  rtems_id scheduler_id;
+  rtems_task_priority priority;
+  rtems_task_priority priority_2;
+
+  sc = rtems_task_get_scheduler(RTEMS_SELF, &scheduler_id);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+
+  sc = rtems_task_get_priority(RTEMS_SELF, scheduler_id, NULL);
+  rtems_test_assert(sc == RTEMS_INVALID_ADDRESS);
+
+  priority = 0;
+
+  sc = rtems_task_get_priority(RTEMS_SELF, invalid_id, &priority);
+  rtems_test_assert(sc == RTEMS_INVALID_ID);
+  rtems_test_assert(priority == 0);
+
+  sc = rtems_task_get_priority(invalid_id, scheduler_id, &priority);
+  rtems_test_assert(sc == RTEMS_INVALID_ID);
+  rtems_test_assert(priority == 0);
+
+  sc = rtems_task_set_priority(RTEMS_SELF, RTEMS_CURRENT_PRIORITY, &priority);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+  rtems_test_assert(priority != 0);
+
+  priority_2 = 0;
+  sc = rtems_task_get_priority(RTEMS_SELF, scheduler_id, &priority_2);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+  rtems_test_assert(priority_2 == priority);
+
+  priority_2 = 0;
+  sc = rtems_task_get_priority(rtems_task_self(), scheduler_id, &priority_2);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+  rtems_test_assert(priority_2 == priority);
+}
+
 static void Init(rtems_task_argument arg)
 {
   rtems_resource_snapshot snapshot;
@@ -425,6 +463,7 @@ static void Init(rtems_task_argument arg)
   test_task_get_set_scheduler();
   test_scheduler_ident();
   test_scheduler_get_processors();
+  test_task_get_priority();
 
   rtems_test_assert(rtems_resource_snapshot_check(&snapshot));
 
diff --git a/testsuites/sptests/spscheduler01/spscheduler01.doc b/testsuites/sptests/spscheduler01/spscheduler01.doc
index d398315b13..2182928722 100644
--- a/testsuites/sptests/spscheduler01/spscheduler01.doc
+++ b/testsuites/sptests/spscheduler01/spscheduler01.doc
@@ -6,8 +6,18 @@ directives:
 
   - rtems_task_get_affinity()
   - rtems_task_set_affinity()
+  - rtems_task_get_scheduler()
+  - rtems_task_set_scheduler()
+  - rtems_scheduler_ident()
+  - rtems_scheduler_get_processor_set()
+  - rtems_task_get_priority()
 
 concepts:
 
   - Ensure that the task set/get affinity functions work on uni-processor
     configurations.
+  - Ensure that the task set/get scheduler functions work on uni-processor
+    configurations.
+  - Ensure that the scheduler functions work on uni-processor configurations.
+  - Ensure that the task get priority function works on uni-processor
+    configurations.