-- 972333fe1e43427849b8a634aa35061e81be3642 by Abseil Team <absl-team@google.com>: Replace deprecated thread annotations macros. PiperOrigin-RevId: 267332619 -- 7039c6dc499a31c372b4872eda0772455931c360 by Gennadiy Rozental <rogeeff@google.com>: Internal change PiperOrigin-RevId: 267220271 -- a3f524d2afc2535686f206a7ce06961016349d7a by Abseil Team <absl-team@google.com>: Factor kernel_timeout out of synchronization. PiperOrigin-RevId: 267217304 -- 90287de4114ef9a06cafe50256a2d03349772c21 by Abseil Team <absl-team@google.com>: Fixed comment typo. PiperOrigin-RevId: 267198532 -- d312c1a1e52aeca1871ff0deead416d09a7f237e by Gennadiy Rozental <rogeeff@google.com>: Internal change PiperOrigin-RevId: 267185804 GitOrigin-RevId: 972333fe1e43427849b8a634aa35061e81be3642 Change-Id: Ia8a2f877c57cef9854aad48f1753af872fc04dc8
		
			
				
	
	
		
			91 lines
		
	
	
	
		
			2.4 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			91 lines
		
	
	
	
		
			2.4 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| // Copyright 2017 The Abseil Authors.
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| //
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| // Licensed under the Apache License, Version 2.0 (the "License");
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| // you may not use this file except in compliance with the License.
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| // You may obtain a copy of the License at
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| //
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| //      https://www.apache.org/licenses/LICENSE-2.0
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| //
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| // Unless required by applicable law or agreed to in writing, software
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| // distributed under the License is distributed on an "AS IS" BASIS,
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| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| // See the License for the specific language governing permissions and
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| // limitations under the License.
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| 
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| #ifndef ABSL_SYNCHRONIZATION_INTERNAL_THREAD_POOL_H_
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| #define ABSL_SYNCHRONIZATION_INTERNAL_THREAD_POOL_H_
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| 
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| #include <cassert>
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| #include <cstddef>
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| #include <functional>
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| #include <queue>
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| #include <thread>  // NOLINT(build/c++11)
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| #include <vector>
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| 
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| #include "absl/base/thread_annotations.h"
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| #include "absl/synchronization/mutex.h"
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| 
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| namespace absl {
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| namespace synchronization_internal {
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| 
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| // A simple ThreadPool implementation for tests.
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| class ThreadPool {
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|  public:
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|   explicit ThreadPool(int num_threads) {
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|     for (int i = 0; i < num_threads; ++i) {
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|       threads_.push_back(std::thread(&ThreadPool::WorkLoop, this));
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|     }
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|   }
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| 
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|   ThreadPool(const ThreadPool &) = delete;
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|   ThreadPool &operator=(const ThreadPool &) = delete;
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| 
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|   ~ThreadPool() {
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|     {
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|       absl::MutexLock l(&mu_);
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|       for (size_t i = 0; i < threads_.size(); i++) {
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|         queue_.push(nullptr);  // Shutdown signal.
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|       }
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|     }
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|     for (auto &t : threads_) {
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|       t.join();
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|     }
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|   }
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| 
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|   // Schedule a function to be run on a ThreadPool thread immediately.
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|   void Schedule(std::function<void()> func) {
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|     assert(func != nullptr);
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|     absl::MutexLock l(&mu_);
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|     queue_.push(std::move(func));
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|   }
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| 
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|  private:
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|   bool WorkAvailable() const ABSL_EXCLUSIVE_LOCKS_REQUIRED(mu_) {
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|     return !queue_.empty();
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|   }
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| 
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|   void WorkLoop() {
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|     while (true) {
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|       std::function<void()> func;
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|       {
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|         absl::MutexLock l(&mu_);
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|         mu_.Await(absl::Condition(this, &ThreadPool::WorkAvailable));
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|         func = std::move(queue_.front());
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|         queue_.pop();
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|       }
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|       if (func == nullptr) {  // Shutdown signal.
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|         break;
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|       }
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|       func();
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|     }
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|   }
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| 
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|   absl::Mutex mu_;
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|   std::queue<std::function<void()>> queue_ ABSL_GUARDED_BY(mu_);
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|   std::vector<std::thread> threads_;
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| };
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| 
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| }  // namespace synchronization_internal
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| }  // namespace absl
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| 
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| #endif  // ABSL_SYNCHRONIZATION_INTERNAL_THREAD_POOL_H_
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