Converting thread entrypoint from lamda to nano::thread_runner::run. (#4147)

nano/lib/threading.cpp

@@ -142,56 +142,34 @@ void nano::thread_attributes::set (boost::thread::attributes & attrs)
 	attrs_l->set_stack_size (8000000); // 8MB
 }
 
-nano::thread_runner::thread_runner (boost::asio::io_context & io_ctx_a, unsigned service_threads_a) :
+nano::thread_runner::thread_runner (boost::asio::io_context & io_ctx_a, unsigned num_threads) :
 	io_guard (boost::asio::make_work_guard (io_ctx_a))
 {
 	boost::thread::attributes attrs;
 	nano::thread_attributes::set (attrs);
-	for (auto i (0u); i < service_threads_a; ++i)
+	for (auto i (0u); i < num_threads; ++i)
 	{
-		threads.emplace_back (attrs, [&io_ctx_a] () {
+		threads.emplace_back (attrs, [this, &io_ctx_a] () {
 			nano::thread_role::set (nano::thread_role::name::io);
+
+			// In a release build, catch and swallow any exceptions,
+			// In debug mode let if fall through
+
+#ifndef NDEBUG
+			run (io_ctx_a);
+#else
 			try
 			{
-#if NANO_ASIO_HANDLER_TRACKING == 0
+				run (io_ctx_a);
-				io_ctx_a.run ();
-#else
-				nano::timer<> timer;
-				timer.start ();
-				while (true)
-				{
-					timer.restart ();
-					// Run at most 1 completion handler and record the time it took to complete (non-blocking)
-					auto count = io_ctx_a.poll_one ();
-					if (count == 1 && timer.since_start ().count () >= NANO_ASIO_HANDLER_TRACKING)
-					{
-						auto timestamp = std::chrono::duration_cast<std::chrono::microseconds> (std::chrono::system_clock::now ().time_since_epoch ()).count ();
-						std::cout << (boost::format ("[%1%] io_thread held for %2%ms") % timestamp % timer.since_start ().count ()).str () << std::endl;
-					}
-					// Sleep for a bit to give more time slices to other threads
-					std::this_thread::sleep_for (std::chrono::milliseconds (5));
-					std::this_thread::yield ();
-				}
-#endif
 			}
 			catch (std::exception const & ex)
 			{
 				std::cerr << ex.what () << std::endl;
-#ifndef NDEBUG
-				throw;
-#endif
 			}
 			catch (...)
 			{
-#ifndef NDEBUG
-				/*
-				 * In a release build, catch and swallow the
-				 * io_context exception, in debug mode pass it
-				 * on
-				 */
-				throw;
-#endif
 			}
+#endif
 		});
 	}
 }
@@ -201,6 +179,30 @@ nano::thread_runner::~thread_runner ()
 	join ();
 }
 
+void nano::thread_runner::run (boost::asio::io_context & io_ctx_a)
+{
+#if NANO_ASIO_HANDLER_TRACKING == 0
+	io_ctx_a.run ();
+#else
+	nano::timer<> timer;
+	timer.start ();
+	while (true)
+	{
+		timer.restart ();
+		// Run at most 1 completion handler and record the time it took to complete (non-blocking)
+		auto count = io_ctx_a.poll_one ();
+		if (count == 1 && timer.since_start ().count () >= NANO_ASIO_HANDLER_TRACKING)
+		{
+			auto timestamp = std::chrono::duration_cast<std::chrono::microseconds> (std::chrono::system_clock::now ().time_since_epoch ()).count ();
+			std::cout << (boost::format ("[%1%] io_thread held for %2%ms") % timestamp % timer.since_start ().count ()).str () << std::endl;
+		}
+		// Sleep for a bit to give more time slices to other threads
+		std::this_thread::sleep_for (std::chrono::milliseconds (5));
+		std::this_thread::yield ();
+	}
+#endif
+}
+
 void nano::thread_runner::join ()
 {
 	io_guard.reset ();

nano/lib/threading.hpp

@@ -80,14 +80,18 @@ namespace thread_attributes
 class thread_runner final
 {
 public:
-	thread_runner (boost::asio::io_context &, unsigned);
+	thread_runner (boost::asio::io_context &, unsigned num_threads);
 	~thread_runner ();
+
 	/** Tells the IO context to stop processing events.*/
 	void stop_event_processing ();
 	/** Wait for IO threads to complete */
 	void join ();
 	std::vector<boost::thread> threads;
 	boost::asio::executor_work_guard<boost::asio::io_context::executor_type> io_guard;
+
+private:
+	void run (boost::asio::io_context &);
 };
 
 /* Default memory order of normal std::atomic operations is std::memory_order_seq_cst which provides