From 3aaa0172d54f2e7082e337fe83840effc32421e0 Mon Sep 17 00:00:00 2001
From: Nekotekina <nekotekina@gmail.com>
Date: Wed, 24 Feb 2021 13:56:02 +0300
Subject: [PATCH] named_thread: implement "default" event loop

Fixup "sleepy" thread at startup on Windows.
Permit threads which lack operator()() overload.
---
 Utilities/Thread.cpp |  4 +---
 Utilities/Thread.h   | 21 +++++++++++++++++----
 rpcs3/main.cpp       |  5 ++++-
 3 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/Utilities/Thread.cpp b/Utilities/Thread.cpp
index 12ab58c18d..9f7c4c1f10 100644
--- a/Utilities/Thread.cpp
+++ b/Utilities/Thread.cpp
@@ -2336,16 +2336,14 @@ bool thread_base::join(bool dtor) const
 
 		if (i > 20 && Emu.IsStopped())
 		{
-			stamp0 = __rdtsc();
 			atomic_wait_engine::raw_notify(0, get_native_id());
-			stamp0 = __rdtsc() - stamp0;
 			warn = true;
 		}
 	}
 
 	if (warn)
 	{
-		sig_log.error(u8"Thread [%s] is too sleepy. Took %.3fµs to wake it up!", *m_tname.load(), stamp0 / (utils::get_tsc_freq() / 1000000.));
+		sig_log.error(u8"Thread [%s] is too sleepy. Took %.3fµs to wake it up!", *m_tname.load(), (__rdtsc() - stamp0) / (utils::get_tsc_freq() / 1000000.));
 	}
 
 	return (m_sync & 3) == 3;
diff --git a/Utilities/Thread.h b/Utilities/Thread.h
index 1b67009ca4..9e09fdacbc 100644
--- a/Utilities/Thread.h
+++ b/Utilities/Thread.h
@@ -42,6 +42,8 @@ class need_wakeup {};
 template <class Context>
 class named_thread;
 
+class thread_base;
+
 template <typename Ctx, typename X = void, typename... Args>
 struct result_storage
 {
@@ -234,7 +236,7 @@ public:
 	}
 
 	// Wait for both thread sync var and provided atomic var
-	template <typename T, atomic_wait::op op = atomic_wait::op::eq, typename U>
+	template <atomic_wait::op Op = atomic_wait::op::eq, typename T, typename U>
 	static inline void wait_on(T& wait, U old, u64 usec = -1)
 	{
 		auto _this = g_tls_this_thread;
@@ -245,7 +247,7 @@ public:
 		}
 
 		atomic_wait::list<2> list{};
-		list.set<0, op>(wait, old);
+		list.set<0, Op>(wait, old);
 		list.set<1>(_this->m_sync, 0, 4 + 1);
 		list.wait(atomic_wait_timeout{usec <= 0xffff'ffff'ffff'ffff / 1000 ? usec * 1000 : 0xffff'ffff'ffff'ffff});
 	}
@@ -329,12 +331,23 @@ class named_thread final : public Context, result_storage<Context>, thread_base
 		if constexpr (result::empty)
 		{
 			// No result
-			Context::operator()();
+			if constexpr (std::is_invocable_v<Context>)
+			{
+				Context::operator()();
+			}
+			else
+			{
+				// Default event loop
+				while (thread_ctrl::state() != thread_state::aborting)
+				{
+					thread_ctrl::wait();
+				}
+			}
 		}
 		else
 		{
 			// Construct the result using placement new (copy elision should happen)
-			new (result::get()) typename result::type(Context::operator()());
+			new (result::get()) decltype(auto)(Context::operator()());
 		}
 
 		return thread::finalize(thread_state::finished);
diff --git a/rpcs3/main.cpp b/rpcs3/main.cpp
index 97f8698869..baf2fa5fd4 100644
--- a/rpcs3/main.cpp
+++ b/rpcs3/main.cpp
@@ -377,8 +377,11 @@ int main(int argc, char** argv)
 	}
 #endif
 
+	// Initialize TSC freq (in case it isn't)
+	static_cast<void>(utils::get_tsc_freq());
+
 	// Initialize thread pool finalizer (on first use)
-	named_thread("", []{})();
+	static_cast<void>(named_thread("", [](int) {}));
 
 	static std::unique_ptr<logs::listener> log_file;
 	{