| // |
| // impl/thread_pool.ipp |
| // ~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
| // |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| // |
| |
| #ifndef ASIO_IMPL_THREAD_POOL_IPP |
| #define ASIO_IMPL_THREAD_POOL_IPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include "asio/detail/config.hpp" |
| #include <stdexcept> |
| #include "asio/thread_pool.hpp" |
| #include "asio/detail/throw_exception.hpp" |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| |
| struct thread_pool::thread_function |
| { |
| detail::scheduler* scheduler_; |
| |
| void operator()() |
| { |
| #if !defined(ASIO_NO_EXCEPTIONS) |
| try |
| { |
| #endif// !defined(ASIO_NO_EXCEPTIONS) |
| asio::error_code ec; |
| scheduler_->run(ec); |
| #if !defined(ASIO_NO_EXCEPTIONS) |
| } |
| catch (...) |
| { |
| std::terminate(); |
| } |
| #endif// !defined(ASIO_NO_EXCEPTIONS) |
| } |
| }; |
| |
| #if !defined(ASIO_NO_TS_EXECUTORS) |
| namespace detail { |
| |
| inline long default_thread_pool_size() |
| { |
| std::size_t num_threads = thread::hardware_concurrency() * 2; |
| num_threads = num_threads == 0 ? 2 : num_threads; |
| return static_cast<long>(num_threads); |
| } |
| |
| } // namespace detail |
| |
| thread_pool::thread_pool() |
| : scheduler_(add_scheduler(new detail::scheduler(*this, 0, false))), |
| num_threads_(detail::default_thread_pool_size()) |
| { |
| scheduler_.work_started(); |
| |
| thread_function f = { &scheduler_ }; |
| threads_.create_threads(f, static_cast<std::size_t>(num_threads_)); |
| } |
| #endif // !defined(ASIO_NO_TS_EXECUTORS) |
| |
| namespace detail { |
| |
| inline long clamp_thread_pool_size(std::size_t n) |
| { |
| if (n > 0x7FFFFFFF) |
| { |
| std::out_of_range ex("thread pool size"); |
| asio::detail::throw_exception(ex); |
| } |
| return static_cast<long>(n & 0x7FFFFFFF); |
| } |
| |
| } // namespace detail |
| |
| thread_pool::thread_pool(std::size_t num_threads) |
| : scheduler_(add_scheduler(new detail::scheduler( |
| *this, num_threads == 1 ? 1 : 0, false))), |
| num_threads_(detail::clamp_thread_pool_size(num_threads)) |
| { |
| scheduler_.work_started(); |
| |
| thread_function f = { &scheduler_ }; |
| threads_.create_threads(f, static_cast<std::size_t>(num_threads_)); |
| } |
| |
| thread_pool::~thread_pool() |
| { |
| stop(); |
| join(); |
| } |
| |
| void thread_pool::stop() |
| { |
| scheduler_.stop(); |
| } |
| |
| void thread_pool::attach() |
| { |
| ++num_threads_; |
| thread_function f = { &scheduler_ }; |
| f(); |
| } |
| |
| void thread_pool::join() |
| { |
| if (!threads_.empty()) |
| { |
| scheduler_.work_finished(); |
| threads_.join(); |
| } |
| } |
| |
| detail::scheduler& thread_pool::add_scheduler(detail::scheduler* s) |
| { |
| detail::scoped_ptr<detail::scheduler> scoped_impl(s); |
| asio::add_service<detail::scheduler>(*this, scoped_impl.get()); |
| return *scoped_impl.release(); |
| } |
| |
| void thread_pool::wait() |
| { |
| scheduler_.work_finished(); |
| threads_.join(); |
| } |
| |
| } // namespace asio |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #endif // ASIO_IMPL_THREAD_POOL_IPP |