ST / ST_Events-old

This is a fork of the `events` subdirectory of https://github.com/ARMmbed/mbed-os

Dependents:   HelloWorld_CCA01M1 HelloWorld_CCA02M1 CI-data-logger-server HelloWorld_CCA02M1 ... more

This is a fork of the events subdirectory of https://github.com/ARMmbed/mbed-os.

Note, you must import this library with import name: events!!!

mbed_shared_queues.cpp@9831:68f03f5d2dd2, 2017-05-30 (annotated)

Committer:
Kevin Bracey
Date:
Tue May 30 16:12:51 2017 +0300
Revision:
9831:68f03f5d2dd2
Add ability to request a shared event queue



To allow components with a simple need to schedule a few events to not

have to create their own threads, with all the associated memory

overhead, add 2 central calls to get shared normal and an

interrupt-deferral event queues, each dispatched on their own shared

threads.



For non-RTOS systems, just the normal event queue is provided, and the

application would have to dispatch this itself. This

application-dispatch is also available via a config option, to

potentially save memory by reusing the main thread.



Possible future improvement: the ability for separate components to

request a minimum stack size, and have the JSON combine these requests.

(Analogous tooling has already been mooted for mbed TLS config options

like key size).

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Kevin Bracey 9831:68f03f5d2dd2 1 /* events
Kevin Bracey 9831:68f03f5d2dd2 2 * Copyright (c) 2017 ARM Limited
Kevin Bracey 9831:68f03f5d2dd2 3 *
Kevin Bracey 9831:68f03f5d2dd2 4 * Licensed under the Apache License, Version 2.0 (the "License");
Kevin Bracey 9831:68f03f5d2dd2 5 * you may not use this file except in compliance with the License.
Kevin Bracey 9831:68f03f5d2dd2 6 * You may obtain a copy of the License at
Kevin Bracey 9831:68f03f5d2dd2 7 *
Kevin Bracey 9831:68f03f5d2dd2 8 * http://www.apache.org/licenses/LICENSE-2.0
Kevin Bracey 9831:68f03f5d2dd2 9 *
Kevin Bracey 9831:68f03f5d2dd2 10 * Unless required by applicable law or agreed to in writing, software
Kevin Bracey 9831:68f03f5d2dd2 11 * distributed under the License is distributed on an "AS IS" BASIS,
Kevin Bracey 9831:68f03f5d2dd2 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Kevin Bracey 9831:68f03f5d2dd2 13 * See the License for the specific language governing permissions and
Kevin Bracey 9831:68f03f5d2dd2 14 * limitations under the License.
Kevin Bracey 9831:68f03f5d2dd2 15 */
Kevin Bracey 9831:68f03f5d2dd2 16
Kevin Bracey 9831:68f03f5d2dd2 17 #include "events/mbed_shared_queues.h"
Kevin Bracey 9831:68f03f5d2dd2 18 #include "mbed.h"
Kevin Bracey 9831:68f03f5d2dd2 19
Kevin Bracey 9831:68f03f5d2dd2 20 using namespace events;
Kevin Bracey 9831:68f03f5d2dd2 21
Kevin Bracey 9831:68f03f5d2dd2 22 namespace mbed {
Kevin Bracey 9831:68f03f5d2dd2 23
Kevin Bracey 9831:68f03f5d2dd2 24 #ifdef MBED_CONF_RTOS_PRESENT
Kevin Bracey 9831:68f03f5d2dd2 25 /* Create an event queue, and start the thread that dispatches it. Static
Kevin Bracey 9831:68f03f5d2dd2 26 * variables mean this happens once the first time each template instantiation
Kevin Bracey 9831:68f03f5d2dd2 27 * is called. This is currently instantiated no more than twice.
Kevin Bracey 9831:68f03f5d2dd2 28 */
Kevin Bracey 9831:68f03f5d2dd2 29 template
Kevin Bracey 9831:68f03f5d2dd2 30 <osPriority Priority, size_t QueueSize, size_t StackSize>
Kevin Bracey 9831:68f03f5d2dd2 31 EventQueue *do_shared_event_queue_with_thread()
Kevin Bracey 9831:68f03f5d2dd2 32 {
Kevin Bracey 9831:68f03f5d2dd2 33 static uint64_t queue_buffer[QueueSize / sizeof(uint64_t)];
Kevin Bracey 9831:68f03f5d2dd2 34 static EventQueue queue(sizeof queue_buffer, (unsigned char *) queue_buffer);
Kevin Bracey 9831:68f03f5d2dd2 35
Kevin Bracey 9831:68f03f5d2dd2 36 static uint64_t stack[StackSize / sizeof(uint64_t)];
Kevin Bracey 9831:68f03f5d2dd2 37 static Thread thread(Priority, StackSize, (unsigned char *) stack);
Kevin Bracey 9831:68f03f5d2dd2 38
Kevin Bracey 9831:68f03f5d2dd2 39 Thread::State state = thread.get_state();
Kevin Bracey 9831:68f03f5d2dd2 40 if (state == Thread::Inactive || state == Thread::Deleted) {
Kevin Bracey 9831:68f03f5d2dd2 41 osStatus status = thread.start(callback(&queue, &EventQueue::dispatch_forever));
Kevin Bracey 9831:68f03f5d2dd2 42 MBED_ASSERT(status == osOK);
Kevin Bracey 9831:68f03f5d2dd2 43 if (status != osOK) {
Kevin Bracey 9831:68f03f5d2dd2 44 return NULL;
Kevin Bracey 9831:68f03f5d2dd2 45 }
Kevin Bracey 9831:68f03f5d2dd2 46 }
Kevin Bracey 9831:68f03f5d2dd2 47
Kevin Bracey 9831:68f03f5d2dd2 48 return &queue;
Kevin Bracey 9831:68f03f5d2dd2 49 }
Kevin Bracey 9831:68f03f5d2dd2 50 #endif
Kevin Bracey 9831:68f03f5d2dd2 51
Kevin Bracey 9831:68f03f5d2dd2 52 EventQueue *mbed_event_queue()
Kevin Bracey 9831:68f03f5d2dd2 53 {
Kevin Bracey 9831:68f03f5d2dd2 54 #if MBED_CONF_EVENTS_SHARED_DISPATCH_FROM_APPLICATION || !defined MBED_CONF_RTOS_PRESENT
Kevin Bracey 9831:68f03f5d2dd2 55 /* Only create the EventQueue, but no dispatching thread */
Kevin Bracey 9831:68f03f5d2dd2 56 static unsigned char queue_buffer[MBED_CONF_EVENTS_SHARED_EVENTSIZE];
Kevin Bracey 9831:68f03f5d2dd2 57 static EventQueue queue(sizeof queue_buffer, queue_buffer);
Kevin Bracey 9831:68f03f5d2dd2 58
Kevin Bracey 9831:68f03f5d2dd2 59 return &queue;
Kevin Bracey 9831:68f03f5d2dd2 60 #else
Kevin Bracey 9831:68f03f5d2dd2 61 return do_shared_event_queue_with_thread<osPriorityNormal, MBED_CONF_EVENTS_SHARED_EVENTSIZE, MBED_CONF_EVENTS_SHARED_STACKSIZE>();
Kevin Bracey 9831:68f03f5d2dd2 62 #endif
Kevin Bracey 9831:68f03f5d2dd2 63 }
Kevin Bracey 9831:68f03f5d2dd2 64
Kevin Bracey 9831:68f03f5d2dd2 65 #ifdef MBED_CONF_RTOS_PRESENT
Kevin Bracey 9831:68f03f5d2dd2 66 EventQueue *mbed_highprio_event_queue()
Kevin Bracey 9831:68f03f5d2dd2 67 {
Kevin Bracey 9831:68f03f5d2dd2 68 return do_shared_event_queue_with_thread<osPriorityHigh, MBED_CONF_EVENTS_SHARED_HIGHPRIO_EVENTSIZE, MBED_CONF_EVENTS_SHARED_HIGHPRIO_STACKSIZE>();
Kevin Bracey 9831:68f03f5d2dd2 69 }
Kevin Bracey 9831:68f03f5d2dd2 70 #endif
Kevin Bracey 9831:68f03f5d2dd2 71
Kevin Bracey 9831:68f03f5d2dd2 72 }