spdlog/details/thread_pool-inl.h

0001 // Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
0002 // Distributed under the MIT License (http://opensource.org/licenses/MIT)
0003
0004 #pragma once
0005
0006 #ifndef SPDLOG_HEADER_ONLY
0007     #include <spdlog/details/thread_pool.h>
0008 #endif
0009
0010 #include <cassert>
0011 #include <spdlog/common.h>
0012
0013 namespace spdlog {
0014 namespace details {
0015
0016 SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items,
0017                                        size_t threads_n,
0018                                        std::function<void()> on_thread_start,
0019                                        std::function<void()> on_thread_stop)
0020     : q_(q_max_items) {
0021     if (threads_n == 0 || threads_n > 1000) {
0022         throw_spdlog_ex(
0023             "spdlog::thread_pool(): invalid threads_n param (valid "
0024             "range is 1-1000)");
0025     }
0026     for (size_t i = 0; i < threads_n; i++) {
0027         threads_.emplace_back([this, on_thread_start, on_thread_stop] {
0028             on_thread_start();
0029             this->thread_pool::worker_loop_();
0030             on_thread_stop();
0031         });
0032     }
0033 }
0034
0035 SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items,
0036                                        size_t threads_n,
0037                                        std::function<void()> on_thread_start)
0038     : thread_pool(q_max_items, threads_n, on_thread_start, [] {}) {}
0039
0040 SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items, size_t threads_n)
0041     : thread_pool(q_max_items, threads_n, [] {}, [] {}) {}
0042
0043 // message all threads to terminate gracefully join them
0044 SPDLOG_INLINE thread_pool::~thread_pool() {
0045     SPDLOG_TRY {
0046         for (size_t i = 0; i < threads_.size(); i++) {
0047             post_async_msg_(async_msg(async_msg_type::terminate), async_overflow_policy::block);
0048         }
0049
0050         for (auto &t : threads_) {
0051             t.join();
0052         }
0053     }
0054     SPDLOG_CATCH_STD
0055 }
0056
0057 void SPDLOG_INLINE thread_pool::post_log(async_logger_ptr &&worker_ptr,
0058                                          const details::log_msg &msg,
0059                                          async_overflow_policy overflow_policy) {
0060     async_msg async_m(std::move(worker_ptr), async_msg_type::log, msg);
0061     post_async_msg_(std::move(async_m), overflow_policy);
0062 }
0063
0064 void SPDLOG_INLINE thread_pool::post_flush(async_logger_ptr &&worker_ptr,
0065                                            async_overflow_policy overflow_policy) {
0066     post_async_msg_(async_msg(std::move(worker_ptr), async_msg_type::flush), overflow_policy);
0067 }
0068
0069 size_t SPDLOG_INLINE thread_pool::overrun_counter() { return q_.overrun_counter(); }
0070
0071 void SPDLOG_INLINE thread_pool::reset_overrun_counter() { q_.reset_overrun_counter(); }
0072
0073 size_t SPDLOG_INLINE thread_pool::discard_counter() { return q_.discard_counter(); }
0074
0075 void SPDLOG_INLINE thread_pool::reset_discard_counter() { q_.reset_discard_counter(); }
0076
0077 size_t SPDLOG_INLINE thread_pool::queue_size() { return q_.size(); }
0078
0079 void SPDLOG_INLINE thread_pool::post_async_msg_(async_msg &&new_msg,
0080                                                 async_overflow_policy overflow_policy) {
0081     if (overflow_policy == async_overflow_policy::block) {
0082         q_.enqueue(std::move(new_msg));
0083     } else if (overflow_policy == async_overflow_policy::overrun_oldest) {
0084         q_.enqueue_nowait(std::move(new_msg));
0085     } else {
0086         assert(overflow_policy == async_overflow_policy::discard_new);
0087         q_.enqueue_if_have_room(std::move(new_msg));
0088     }
0089 }
0090
0091 void SPDLOG_INLINE thread_pool::worker_loop_() {
0092     while (process_next_msg_()) {
0093     }
0094 }
0095
0096 // process next message in the queue
0097 // return true if this thread should still be active (while no terminate msg
0098 // was received)
0099 bool SPDLOG_INLINE thread_pool::process_next_msg_() {
0100     async_msg incoming_async_msg;
0101     q_.dequeue(incoming_async_msg);
0102
0103     switch (incoming_async_msg.msg_type) {
0104         case async_msg_type::log: {
0105             incoming_async_msg.worker_ptr->backend_sink_it_(incoming_async_msg);
0106             return true;
0107         }
0108         case async_msg_type::flush: {
0109             incoming_async_msg.worker_ptr->backend_flush_();
0110             return true;
0111         }
0112
0113         case async_msg_type::terminate: {
0114             return false;
0115         }
0116
0117         default: {
0118             assert(false);
0119         }
0120     }
0121
0122     return true;
0123 }
0124
0125 }  // namespace details
0126 }  // namespace spdlog