Add option to make Nanostack use global event queue

Author: kjbracey

features/nanostack/nanostack-hal-mbed-cmsis-rtos/mbed_lib.json

@@ -12,11 +12,14 @@
         "critical-section-usable-from-interrupt": {
             "help": "Make critical section API usable from interrupt context. Else a mutex is used as locking primitive. Consult arm_hal_interrupt.c for possible side effects on interrupt latency.",
             "value": false
-        }
-        ,
+        },
         "event-loop-dispatch-from-application": {
             "help": "Application is responsible of message dispatch loop. Else launch a separate thread for event-loop.",
             "value": false
+        },
+        "event-loop-use-mbed-events": {
+            "help": "Use Mbed OS global event queue for Nanostack event loop, rather than our own thread.",
+            "value": false
         }
     }
 }

features/nanostack/nanostack-hal-mbed-cmsis-rtos/ns_event_loop.c

@@ -2,18 +2,20 @@
  * Copyright (c) 2016 ARM Limited, All Rights Reserved
  */
 
-#include <mbed_assert.h>
+#include "mbed_assert.h"
 #include "cmsis.h"
 #include "cmsis_os2.h"
 #include "mbed_rtos_storage.h"
 #include "ns_trace.h"
 
 #include "eventOS_scheduler.h"
 
+#include "ns_event_loop_mutex.h"
 #include "ns_event_loop.h"
 
 #define TRACE_GROUP "evlp"
 
+#if !MBED_CONF_NANOSTACK_HAL_EVENT_LOOP_USE_MBED_EVENTS
 
 #if MBED_CONF_NANOSTACK_HAL_EVENT_LOOP_DISPATCH_FROM_APPLICATION
 
@@ -50,40 +52,6 @@ static const osThreadAttr_t event_thread_attr = {
 static osThreadId_t event_thread_id;
 #endif
 
-static mbed_rtos_storage_mutex_t event_mutex;
-static const osMutexAttr_t event_mutex_attr = {
-  .name = "nanostack_event_mutex",
-  .attr_bits = osMutexRecursive | osMutexPrioInherit | osMutexRobust,
-  .cb_mem = &event_mutex,
-  .cb_size = sizeof event_mutex,
-};
-static osMutexId_t event_mutex_id;
-static osThreadId_t event_mutex_owner_id = NULL;
-static uint32_t owner_count = 0;
-
-void eventOS_scheduler_mutex_wait(void)
-{
-    osMutexAcquire(event_mutex_id, osWaitForever);
-    if (0 == owner_count) {
-        event_mutex_owner_id = osThreadGetId();
-    }
-    owner_count++;
-}
-
-void eventOS_scheduler_mutex_release(void)
-{
-    owner_count--;
-    if (0 == owner_count) {
-        event_mutex_owner_id = NULL;
-    }
-    osMutexRelease(event_mutex_id);
-}
-
-uint8_t eventOS_scheduler_mutex_is_owner(void)
-{
-    return osThreadGetId() == event_mutex_owner_id ? 1 : 0;
-}
-
 void eventOS_scheduler_signal(void)
 {
     // XXX why does signal set lock if called with irqs disabled?
@@ -124,8 +92,7 @@ static void event_loop_thread(void *arg)
 // if it is not ran in a separate thread.
 void ns_event_loop_init(void)
 {
-    event_mutex_id = osMutexNew(&event_mutex_attr);
-    MBED_ASSERT(event_mutex_id != NULL);
+    ns_event_loop_mutex_init();
 
     // If a separate event loop thread is not used, the signaling
     // happens via event flags instead of thread flags. This allows one to
@@ -148,3 +115,5 @@ void ns_event_loop_thread_start(void)
 {
 }
 #endif
+
+#endif // !MBED_CONF_NANOSTACK_HAL_EVENT_LOOP_USE_MBED_EVENTS

features/nanostack/nanostack-hal-mbed-cmsis-rtos/ns_event_loop_mbed.cpp

@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2018 ARM Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "mbed_assert.h"
+#include "platform/arm_hal_interrupt.h"
+#include "cmsis.h"
+#include "cmsis_os2.h"
+#include "mbed_rtos_storage.h"
+#include "ns_trace.h"
+
+#include "eventOS_scheduler.h"
+
+#include "mbed_error.h"
+#include "mbed_shared_queues.h"
+#include "events/Event.h"
+#include "ns_event_loop_mutex.h"
+#include "ns_event_loop.h"
+
+#define TRACE_GROUP "evlp"
+
+#if MBED_CONF_NANOSTACK_HAL_EVENT_LOOP_USE_MBED_EVENTS
+
+using events::EventQueue;
+using events::Event;
+
+static Event<void()> *event;
+static volatile int event_pending;
+static volatile bool started;
+
+void eventOS_scheduler_signal(void)
+{
+    platform_enter_critical();
+    if (started && event_pending == 0) {
+        event_pending = event->post();
+        MBED_ASSERT(event_pending != 0);
+    }
+    platform_exit_critical();
+}
+
+void eventOS_scheduler_idle(void)
+{
+    error("Shouldn't be called");
+}
+
+static void do_dispatch_with_mutex_held()
+{
+    platform_enter_critical();
+    event_pending = 0;
+    platform_exit_critical();
+
+    /* Process only 1 Nanostack event at a time, to try to be nice to
+     * others on the global queue.
+     */
+    eventOS_scheduler_mutex_wait();
+    bool dispatched = eventOS_scheduler_dispatch_event();
+    eventOS_scheduler_mutex_release();
+
+    /* Go round again if (potentially) more */
+    if (dispatched) {
+        eventOS_scheduler_signal();
+    }
+}
+
+void ns_event_loop_init(void)
+{
+    ns_event_loop_mutex_init();
+}
+
+void ns_event_loop_thread_create(void)
+{
+    EventQueue *equeue = mbed::mbed_event_queue();
+    MBED_ASSERT(equeue != NULL);
+
+    event = new Event<void()>(equeue, do_dispatch_with_mutex_held);
+    MBED_ASSERT(event != NULL);
+}
+
+void ns_event_loop_thread_start(void)
+{
+    started = true;
+    eventOS_scheduler_signal();
+}
+
+#endif // MBED_CONF_NANOSTACK_HAL_EVENT_LOOP_USE_MBED_EVENTS

features/nanostack/nanostack-hal-mbed-cmsis-rtos/ns_event_loop_mutex.c

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2018 ARM Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "mbed_assert.h"
+#include "cmsis.h"
+#include "cmsis_os2.h"
+#include "mbed_rtos_storage.h"
+#include "ns_trace.h"
+
+#include "eventOS_scheduler.h"
+
+#include "ns_event_loop_mutex.h"
+
+#define TRACE_GROUP "evlm"
+
+static mbed_rtos_storage_mutex_t event_mutex;
+static const osMutexAttr_t event_mutex_attr = {
+  .name = "nanostack_event_mutex",
+  .attr_bits = osMutexRecursive | osMutexPrioInherit | osMutexRobust,
+  .cb_mem = &event_mutex,
+  .cb_size = sizeof event_mutex,
+};
+static osMutexId_t event_mutex_id;
+static osThreadId_t event_mutex_owner_id = NULL;
+static uint32_t owner_count = 0;
+
+void eventOS_scheduler_mutex_wait(void)
+{
+    osMutexAcquire(event_mutex_id, osWaitForever);
+    if (0 == owner_count) {
+        event_mutex_owner_id = osThreadGetId();
+    }
+    owner_count++;
+}
+
+void eventOS_scheduler_mutex_release(void)
+{
+    owner_count--;
+    if (0 == owner_count) {
+        event_mutex_owner_id = NULL;
+    }
+    osMutexRelease(event_mutex_id);
+}
+
+uint8_t eventOS_scheduler_mutex_is_owner(void)
+{
+    return osThreadGetId() == event_mutex_owner_id ? 1 : 0;
+}
+
+void ns_event_loop_mutex_init(void)
+{
+    event_mutex_id = osMutexNew(&event_mutex_attr);
+    MBED_ASSERT(event_mutex_id != NULL);
+}
+

features/nanostack/nanostack-hal-mbed-cmsis-rtos/ns_event_loop_mutex.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2018 ARM Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** \internal  Initialise the scheduler mutex
+ *
+ * Initialises the mutex used by the implementation of
+ * eventOS_scheduler_mutex_wait(). Must be called before scheduler is used.
+ */
+void ns_event_loop_mutex_init(void);
+
+#ifdef __cplusplus
+}
+#endif
+