| // Copyright 2023 The Pigweed Authors |
| // |
| // 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 |
| // |
| // https://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. |
| #pragma once |
| |
| #include "pw_async/dispatcher.h" |
| #include "pw_async/task.h" |
| #include "pw_sync/interrupt_spin_lock.h" |
| #include "pw_sync/lock_annotations.h" |
| #include "pw_sync/timed_thread_notification.h" |
| #include "pw_thread/thread_core.h" |
| |
| namespace pw::async { |
| |
| /// BasicDispatcher is a generic implementation of Dispatcher. |
| class BasicDispatcher final : public Dispatcher, public thread::ThreadCore { |
| public: |
| explicit BasicDispatcher() = default; |
| ~BasicDispatcher() override; |
| |
| /// Execute all runnable tasks and return without waiting. |
| void RunUntilIdle(); |
| |
| /// Run the dispatcher until Now() has reached `end_time`, executing all tasks |
| /// that come due before then. |
| void RunUntil(chrono::SystemClock::time_point end_time); |
| |
| /// Run the dispatcher until `duration` has elapsed, executing all tasks that |
| /// come due in that period. |
| void RunFor(chrono::SystemClock::duration duration); |
| |
| /// Stop processing tasks. If the dispatcher is serving a task loop, break out |
| /// of the loop, dequeue all waiting tasks, and call their TaskFunctions with |
| /// a PW_STATUS_CANCELLED status. If no task loop is being served, execute the |
| /// dequeueing procedure the next time the Dispatcher is run. |
| void RequestStop() PW_LOCKS_EXCLUDED(lock_); |
| |
| // ThreadCore overrides: |
| |
| /// Run the dispatcher until RequestStop() is called. Overrides |
| /// ThreadCore::Run() so that BasicDispatcher is compatible with |
| /// pw::thread::Thread. |
| void Run() override PW_LOCKS_EXCLUDED(lock_); |
| |
| // Dispatcher overrides: |
| void PostAt(Task& task, chrono::SystemClock::time_point time) override; |
| bool Cancel(Task& task) override PW_LOCKS_EXCLUDED(lock_); |
| |
| // VirtualSystemClock overrides: |
| chrono::SystemClock::time_point now() override { |
| return chrono::SystemClock::now(); |
| } |
| |
| private: |
| // Insert |task| into task_queue_ maintaining its min-heap property, keyed by |
| // |time_due|. |
| void PostTaskInternal(backend::NativeTask& task, |
| chrono::SystemClock::time_point time_due) |
| PW_LOCKS_EXCLUDED(lock_); |
| |
| // If no tasks are due, sleep until a notification is received, the next task |
| // comes due, or a timeout elapses; whichever occurs first. |
| void MaybeSleep() PW_EXCLUSIVE_LOCKS_REQUIRED(lock_); |
| |
| // Dequeue and run each task that is due. |
| void ExecuteDueTasks() PW_EXCLUSIVE_LOCKS_REQUIRED(lock_); |
| |
| // Dequeue each task and call each TaskFunction with a PW_STATUS_CANCELLED |
| // status. |
| void DrainTaskQueue() PW_EXCLUSIVE_LOCKS_REQUIRED(lock_); |
| |
| sync::InterruptSpinLock lock_; |
| sync::TimedThreadNotification timed_notification_; |
| bool stop_requested_ PW_GUARDED_BY(lock_) = false; |
| // A priority queue of scheduled Tasks sorted by earliest due times first. |
| IntrusiveList<backend::NativeTask> task_queue_ PW_GUARDED_BY(lock_); |
| }; |
| |
| } // namespace pw::async |