From 2b6ee636cacc4a560c35deac109fa05f63d27d8f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Piotr=20W=C3=B3jcik?=
 <3044353+pwojcikdev@users.noreply.github.com>
Date: Mon, 15 Apr 2024 10:04:52 +0200
Subject: [PATCH] Constexpr check NANO_ASIO_HANDLER_TRACKING (#4562)

---
 nano/lib/thread_runner.cpp  | 38 +++++++++++++++++++------------------
 nano/lib/thread_runner.hpp  | 11 ++++++++++-
 nano/test_common/system.cpp | 27 ++++++++++++++------------
 3 files changed, 45 insertions(+), 31 deletions(-)

diff --git a/nano/lib/thread_runner.cpp b/nano/lib/thread_runner.cpp
index 62a7625cd1..5f36c82a82 100644
--- a/nano/lib/thread_runner.cpp
+++ b/nano/lib/thread_runner.cpp
@@ -24,7 +24,7 @@ nano::thread_runner::thread_runner (std::shared_ptr<boost::asio::io_context> io_
 			try
 			{
 				logger.debug (nano::log::type::thread_runner, "Thread #{} ({}) started", i, to_string (role));
-				run (*io_ctx);
+				run ();
 				logger.debug (nano::log::type::thread_runner, "Thread #{} ({}) stopped", i, to_string (role));
 			}
 			catch (std::exception const & ex)
@@ -49,28 +49,30 @@ nano::thread_runner::~thread_runner ()
 	join ();
 }
 
-void nano::thread_runner::run (boost::asio::io_context & io_ctx_a)
+void nano::thread_runner::run ()
 {
-#if NANO_ASIO_HANDLER_TRACKING == 0
-	io_ctx_a.run ();
-#else
-	nano::timer<> timer;
-	timer.start ();
-	while (true)
+	if constexpr (nano::asio_handler_tracking_threshold () == 0)
 	{
-		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)
+		io_ctx->run ();
+	}
+	else
+	{
+		nano::timer<> timer;
+		timer.start ();
+		while (true)
 		{
-			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;
+			timer.restart ();
+			// Run at most 1 completion handler and record the time it took to complete (non-blocking)
+			auto count = io_ctx->poll_one ();
+			if (count == 1 && timer.since_start ().count () >= nano::asio_handler_tracking_threshold ())
+			{
+				logger.warn (nano::log::type::system, "Async handler processing took too long: {}ms", timer.since_start ().count ());
+			}
+			// 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 ();
 		}
-		// 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 ()
diff --git a/nano/lib/thread_runner.hpp b/nano/lib/thread_runner.hpp
index 116a1aa65b..f1d557a883 100644
--- a/nano/lib/thread_runner.hpp
+++ b/nano/lib/thread_runner.hpp
@@ -31,6 +31,15 @@ class thread_runner final
 	std::vector<boost::thread> threads;
 
 private:
-	void run (boost::asio::io_context &);
+	void run ();
 };
+
+constexpr unsigned asio_handler_tracking_threshold ()
+{
+#if NANO_ASIO_HANDLER_TRACKING == 0
+	return 0;
+#else
+	return NANO_ASIO_HANDLER_TRACKING;
+#endif
+}
 } // namespace nano
diff --git a/nano/test_common/system.cpp b/nano/test_common/system.cpp
index d5bc43b1d0..fda7ffbc8b 100644
--- a/nano/test_common/system.cpp
+++ b/nano/test_common/system.cpp
@@ -1,5 +1,6 @@
 #include <nano/crypto_lib/random_pool.hpp>
 #include <nano/lib/blocks.hpp>
+#include <nano/lib/thread_runner.hpp>
 #include <nano/node/active_transactions.hpp>
 #include <nano/node/common.hpp>
 #include <nano/node/transport/tcp_listener.hpp>
@@ -335,22 +336,24 @@ void nano::test::system::deadline_set (std::chrono::duration<double, std::nano>
 
 std::error_code nano::test::system::poll (std::chrono::nanoseconds const & wait_time)
 {
-#if NANO_ASIO_HANDLER_TRACKING == 0
-	io_ctx->run_one_for (wait_time);
-#else
-	nano::timer<> timer;
-	timer.start ();
-	auto count = io_ctx.poll_one ();
-	if (count == 0)
+	if constexpr (nano::asio_handler_tracking_threshold () == 0)
 	{
-		std::this_thread::sleep_for (wait_time);
+		io_ctx->run_one_for (wait_time);
 	}
-	else if (count == 1 && timer.since_start ().count () >= NANO_ASIO_HANDLER_TRACKING)
+	else
 	{
-		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;
+		nano::timer<> timer;
+		timer.start ();
+		auto count = io_ctx->poll_one ();
+		if (count == 0)
+		{
+			std::this_thread::sleep_for (wait_time);
+		}
+		else if (count == 1 && timer.since_start ().count () >= nano::asio_handler_tracking_threshold ())
+		{
+			logger.warn (nano::log::type::system, "Async handler processing took too long: {}ms", timer.since_start ().count ());
+		}
 	}
-#endif
 
 	std::error_code ec;
 	if (std::chrono::steady_clock::now () > deadline)