From 02a24cdb7d072249cf023fcd66622fcafa3e6bbf Mon Sep 17 00:00:00 2001
From: Stuart Kenny <stuartkenny@gmail.com>
Date: Thu, 8 Jul 2021 08:34:48 +0100
Subject: [PATCH] Fix black screen on multiple libretro content loads.

Moves ThreadPool teardown to retro_unload_game. Gives ThreadPool threads some breathing room to terminate before game load starts spamming it with tasks.
---
 Common/Thread/ThreadManager.cpp | 4 ----
 Common/Thread/ThreadManager.h   | 3 +--
 libretro/libretro.cpp           | 2 ++
 3 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/Common/Thread/ThreadManager.cpp b/Common/Thread/ThreadManager.cpp
index 8ac9ac0a22..4647713ccd 100644
--- a/Common/Thread/ThreadManager.cpp
+++ b/Common/Thread/ThreadManager.cpp
@@ -98,10 +98,6 @@ static void WorkerThreadFunc(GlobalThreadContext *global, ThreadContext *thread)
 }
 
 void ThreadManager::Init(int numRealCores, int numLogicalCoresPerCpu) {
-	if (!global_->threads_.empty()) {
-		Teardown();
-	}
-
 	numComputeThreads_ = std::min(numRealCores * numLogicalCoresPerCpu, MAX_CORES_TO_USE);
 	int numThreads = numComputeThreads_ + EXTRA_THREADS;
 	numThreads_ = numThreads;
diff --git a/Common/Thread/ThreadManager.h b/Common/Thread/ThreadManager.h
index b36f8ed26f..822997d921 100644
--- a/Common/Thread/ThreadManager.h
+++ b/Common/Thread/ThreadManager.h
@@ -46,6 +46,7 @@ public:
 	void Init(int numCores, int numLogicalCoresPerCpu);
 	void EnqueueTask(Task *task, TaskType taskType);
 	void EnqueueTaskOnThread(int threadNum, Task *task, TaskType taskType);
+	void Teardown();
 
 	// Currently does nothing. It will always be best-effort - maybe it cancels,
 	// maybe it doesn't. Note that the id is the id() returned by the task. You need to make that
@@ -57,8 +58,6 @@ public:
 	int GetNumLooperThreads() const;
 
 private:
-	void Teardown();
-
 	GlobalThreadContext *global_ = nullptr;
 
 	int numThreads_ = 0;
diff --git a/libretro/libretro.cpp b/libretro/libretro.cpp
index cf8be3959e..c5f6f9a0fc 100644
--- a/libretro/libretro.cpp
+++ b/libretro/libretro.cpp
@@ -675,6 +675,8 @@ void retro_unload_game(void)
 	delete ctx;
 	ctx = nullptr;
 	PSP_CoreParameter().graphicsContext = nullptr;
+
+   g_threadManager.Teardown();
 }
 
 void retro_reset(void)