rtems: Add rtems_scheduler_map_priority_from_posix()

Update #3881.

cpukit/Makefile.am

@@ -769,6 +769,7 @@ librtemscpu_a_SOURCES += rtems/src/schedulergetprocessorset.c
 librtemscpu_a_SOURCES += rtems/src/scheduleridentbyprocessor.c
 librtemscpu_a_SOURCES += rtems/src/scheduleridentbyprocessorset.c
 librtemscpu_a_SOURCES += rtems/src/schedulerident.c
+librtemscpu_a_SOURCES += rtems/src/schedulermapfromposix.c
 librtemscpu_a_SOURCES += rtems/src/schedulermaptoposix.c
 librtemscpu_a_SOURCES += rtems/src/schedulerremoveprocessor.c
 librtemscpu_a_SOURCES += rtems/src/sem.c

cpukit/include/rtems/rtems/tasks.h

@@ -754,6 +754,24 @@ rtems_status_code rtems_scheduler_map_priority_to_posix(
   int                 *posix_priority
 );
 
+/**
+ * @brief Map a POSIX thread priority to the corresponding task priority.
+ *
+ * @param scheduler_id Identifier of the scheduler instance.
+ * @param posix_priority The POSIX thread priority to map.
+ * @param[out] priority Pointer to a task priority value.
+ *
+ * @retval RTEMS_SUCCESSFUL Successful operation.
+ * @retval RTEMS_INVALID_ADDRESS The @a priority parameter is @c NULL.
+ * @retval RTEMS_INVALID_ID Invalid scheduler instance identifier.
+ * @retval RTEMS_INVALID_PRIORITY Invalid POSIX thread priority.
+ */
+rtems_status_code rtems_scheduler_map_priority_from_posix(
+  rtems_id             scheduler_id,
+  int                  posix_priority,
+  rtems_task_priority *priority
+);
+
 /**@}*/
 
 #ifdef __cplusplus

cpukit/rtems/src/schedulermapfromposix.c

@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup ClassicTasks
+ *
+ * @brief Implementation of rtems_scheduler_map_priority_from_posix().
+ */
+
+/*
+ * Copyright (C) 2020 embedded brains GmbH (http://www.embedded-brains.de)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/rtems/tasks.h>
+#include <rtems/score/schedulerimpl.h>
+
+rtems_status_code rtems_scheduler_map_priority_from_posix(
+  rtems_id             scheduler_id,
+  int                  posix_priority,
+  rtems_task_priority *priority
+)
+{
+  const Scheduler_Control *scheduler;
+
+  if ( priority == NULL ) {
+    return RTEMS_INVALID_ADDRESS;
+  }
+
+  scheduler = _Scheduler_Get_by_id( scheduler_id );
+  if ( scheduler == NULL ) {
+    return RTEMS_INVALID_ID;
+  }
+
+  if ( posix_priority < 1 ) {
+    return RTEMS_INVALID_PRIORITY;
+  }
+
+  if ( posix_priority >= scheduler->maximum_priority ) {
+    return RTEMS_INVALID_PRIORITY;
+  }
+
+  *priority = scheduler->maximum_priority - (Priority_Control) posix_priority;
+  return RTEMS_SUCCESSFUL;
+}

testsuites/sptests/spscheduler01/init.c

@@ -534,6 +534,49 @@ static void test_scheduler_map_to_posix(void)
   rtems_test_assert(posix_priority == 1);
 }
 
+static void test_scheduler_map_from_posix(void)
+{
+  rtems_status_code sc;
+  rtems_task_priority priority;
+  rtems_id scheduler_id;
+
+  priority = 123;
+  sc = rtems_scheduler_map_priority_from_posix(invalid_id, 1, &priority);
+  rtems_test_assert(sc == RTEMS_INVALID_ID);
+  rtems_test_assert(priority == 123);
+
+  sc = rtems_task_get_scheduler(RTEMS_SELF, &scheduler_id);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+
+  sc = rtems_scheduler_map_priority_from_posix(scheduler_id, 1, NULL);
+  rtems_test_assert(sc == RTEMS_INVALID_ADDRESS);
+
+  priority = 123;
+  sc = rtems_scheduler_map_priority_from_posix(scheduler_id, -1, &priority);
+  rtems_test_assert(sc == RTEMS_INVALID_PRIORITY);
+  rtems_test_assert(priority == 123);
+
+  priority = 123;
+  sc = rtems_scheduler_map_priority_from_posix(scheduler_id, 0, &priority);
+  rtems_test_assert(sc == RTEMS_INVALID_PRIORITY);
+  rtems_test_assert(priority == 123);
+
+  priority = 123;
+  sc = rtems_scheduler_map_priority_from_posix(scheduler_id, 255, &priority);
+  rtems_test_assert(sc == RTEMS_INVALID_PRIORITY);
+  rtems_test_assert(priority == 123);
+
+  priority = 123;
+  sc = rtems_scheduler_map_priority_from_posix(scheduler_id, 1, &priority);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+  rtems_test_assert(priority == 254);
+
+  priority = 123;
+  sc = rtems_scheduler_map_priority_from_posix(scheduler_id, 254, &priority);
+  rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+  rtems_test_assert(priority == 1);
+}
+
 static void test_scheduler_get_processors(void)
 {
   rtems_status_code sc;
@@ -663,6 +706,7 @@ static void Init(rtems_task_argument arg)
   test_scheduler_ident();
   test_scheduler_get_max_prio();
   test_scheduler_map_to_posix();
+  test_scheduler_map_from_posix();
   test_scheduler_get_processors();
   test_scheduler_add_remove_processors();
   test_task_get_priority();