From 88864140133e5eb50f17fbe94ae4336f9ab9ae10 Mon Sep 17 00:00:00 2001
From: Nekotekina <nekotekina@gmail.com>
Date: Sat, 27 Jul 2019 17:08:45 +0300
Subject: [PATCH] Use atomic wait in shared_mutex and semaphore

---
 Utilities/mutex.cpp | 27 ++++++++++++++++-----------
 Utilities/sema.cpp  | 20 +++-----------------
 2 files changed, 19 insertions(+), 28 deletions(-)

diff --git a/Utilities/mutex.cpp b/Utilities/mutex.cpp
index ae0436c188..b8d199ea56 100644
--- a/Utilities/mutex.cpp
+++ b/Utilities/mutex.cpp
@@ -1,7 +1,4 @@
 #include "mutex.h"
-#include "sync.h"
-
-#include <climits>
 
 void shared_mutex::imp_lock_shared(u32 val)
 {
@@ -122,24 +119,32 @@ void shared_mutex::imp_unlock_vip(u32 old)
 
 void shared_mutex::imp_wait()
 {
-	while (!balanced_wait_until(m_value, -1, [&](u32& value, auto...)
+	while (true)
 	{
-		if (value >= c_sig)
+		const auto [old, ok] = m_value.fetch_op([](u32& value)
 		{
-			value -= c_sig;
-			return true;
+			if (value >= c_sig)
+			{
+				value -= c_sig;
+				return true;
+			}
+
+			return false;
+		});
+
+		if (ok)
+		{
+			break;
 		}
 
-		return false;
-	}))
-	{
+		m_value.wait(old);
 	}
 }
 
 void shared_mutex::imp_signal()
 {
 	m_value += c_sig;
-	balanced_awaken(m_value, 1);
+	m_value.notify_one();
 }
 
 void shared_mutex::imp_lock(u32 val)
diff --git a/Utilities/sema.cpp b/Utilities/sema.cpp
index 7e2a4ca834..e4e3e7345f 100644
--- a/Utilities/sema.cpp
+++ b/Utilities/sema.cpp
@@ -1,5 +1,4 @@
 #include "sema.h"
-#include "sync.h"
 
 void semaphore_base::imp_wait()
 {
@@ -15,14 +14,6 @@ void semaphore_base::imp_wait()
 		}
 	}
 
-#ifdef _WIN32
-	const s32 value = m_value.fetch_sub(1);
-
-	if (value <= 0)
-	{
-		NtWaitForKeyedEvent(nullptr, &m_value, false, nullptr);
-	}
-#else
 	while (true)
 	{
 		// Try hard way
@@ -51,24 +42,19 @@ void semaphore_base::imp_wait()
 		if (value >= 0)
 		{
 			// Signal other waiter to wake up or to restore sign bit
-			futex(&m_value, FUTEX_WAKE_PRIVATE, 1);
+			m_value.notify_one();
 			return;
 		}
 
-		futex(&m_value, FUTEX_WAIT_PRIVATE, value);
+		m_value.wait(value);
 	}
-#endif
 }
 
 void semaphore_base::imp_post(s32 _old)
 {
 	verify("semaphore_base: overflow" HERE), _old < 0;
 
-#ifdef _WIN32
-	NtReleaseKeyedEvent(nullptr, &m_value, false, nullptr);
-#else
-	futex(&m_value, FUTEX_WAKE_PRIVATE, 1);
-#endif
+	m_value.notify_one();
 }
 
 bool semaphore_base::try_post(s32 _max)