| /* |
| * |
| * Copyright 2019 gRPC 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 |
| * |
| * 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 <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/iomgr/poller/eventmanager_libuv.h" |
| |
| #include <grpc/support/time.h> |
| |
| grpc::experimental::LibuvEventManager::Options::Options() : num_workers_(-1) {} |
| grpc::experimental::LibuvEventManager::Options::Options(int num_workers) |
| : num_workers_(num_workers) {} |
| |
| grpc::experimental::LibuvEventManager::LibuvEventManager(const Options& options) |
| : options_(options) { |
| int num_workers = options_.num_workers(); |
| // Number of workers can't be 0 if we do not accept thread donation. |
| // TODO(guantaol): replaces the hard-coded number with a flag. |
| if (num_workers <= 0) num_workers = 32; |
| |
| for (int i = 0; i < num_workers; i++) { |
| workers_.emplace_back( |
| options_.thread_name_prefix().c_str(), |
| [](void* em) { static_cast<LibuvEventManager*>(em)->RunWorkerLoop(); }, |
| this); |
| workers_.back().Start(); |
| } |
| } |
| |
| grpc::experimental::LibuvEventManager::~LibuvEventManager() { |
| Shutdown(); |
| for (auto& th : workers_) { |
| th.Join(); |
| } |
| } |
| |
| void grpc::experimental::LibuvEventManager::RunWorkerLoop() { |
| while (true) { |
| // TODO(guantaol): extend the worker loop with real work. |
| if (ShouldStop()) return; |
| gpr_sleep_until(gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC), |
| gpr_time_from_micros(10, GPR_TIMESPAN))); |
| } |
| } |
| |
| bool grpc::experimental::LibuvEventManager::ShouldStop() { |
| return should_stop_.Load(grpc_core::MemoryOrder::ACQUIRE) != 0; |
| } |
| |
| void grpc::experimental::LibuvEventManager::Shutdown() { |
| if (should_stop_.Load(grpc_core::MemoryOrder::ACQUIRE)) { |
| return; // Already shut down. |
| } |
| |
| { |
| grpc_core::MutexLock lock(&shutdown_mu_); |
| while (shutdown_refcount_.Load(grpc_core::MemoryOrder::ACQUIRE) > 0) { |
| shutdown_cv_.Wait(&shutdown_mu_); |
| } |
| } |
| should_stop_.Store(true, grpc_core::MemoryOrder::RELEASE); |
| } |
| |
| void grpc::experimental::LibuvEventManager::ShutdownRef() { |
| shutdown_refcount_.FetchAdd(1, grpc_core::MemoryOrder::RELAXED); |
| } |
| |
| void grpc::experimental::LibuvEventManager::ShutdownUnref() { |
| if (shutdown_refcount_.FetchSub(1, grpc_core::MemoryOrder::ACQ_REL) == 1) { |
| grpc_core::MutexLock lock(&shutdown_mu_); |
| shutdown_cv_.Signal(); |
| } |
| } |