/* * Copyright (c) Meta Platforms, Inc. and affiliates. * * 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. */ #pragma once #include #include #include #include namespace folly { // `SoftRealTimeExecutor` is an executor that performs some priority-based // scheduling with a deadline assigned to each task. __Soft__ real-time // means that not every deadline is guaranteed to be met. class SoftRealTimeExecutor : public virtual Executor { public: void add(Func) override = 0; // Add a task with an assigned abstract deadline. // // NOTE: The type of `deadline` was chosen to be an integral rather than // a typed time point or duration (e.g., `std::chrono::time_point`) to allow // for flexibility. While the deadline for a task may be a time point, // it could also be a duration or the size of the task, which emulates // rate-monotonic scheduling that prioritizes small tasks. It also enables, // for example, tiered scheduling (strictly prioritizing a category of tasks) // by assigning the high-bit of the deadline. void add(Func func, uint64_t deadline) { add(std::move(func), /* total */ 1, deadline); } virtual void add(Func, std::size_t total, uint64_t deadline) = 0; virtual void add(std::vector, uint64_t deadline) = 0; }; } // namespace folly