From 8f6245be9a344f53cfca6804bf883a491d113dae Mon Sep 17 00:00:00 2001
From: bunnei <bunneidev@gmail.com>
Date: Sat, 26 Nov 2022 13:46:38 -0800
Subject: [PATCH 1/2] core: Use atomic instead of a lock to protect is_paused.

- This allows us to call IsPaused() elsewhere if we are holding the suspend lock.
---
 src/core/core.cpp | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/core/core.cpp b/src/core/core.cpp
index d8934be528..94d4e22124 100644
--- a/src/core/core.cpp
+++ b/src/core/core.cpp
@@ -189,7 +189,7 @@ struct System::Impl {
 
         kernel.Suspend(false);
         core_timing.SyncPause(false);
-        is_paused = false;
+        is_paused.store(false, std::memory_order_relaxed);
 
         return status;
     }
@@ -200,14 +200,13 @@ struct System::Impl {
 
         core_timing.SyncPause(true);
         kernel.Suspend(true);
-        is_paused = true;
+        is_paused.store(true, std::memory_order_relaxed);
 
         return status;
     }
 
     bool IsPaused() const {
-        std::unique_lock lk(suspend_guard);
-        return is_paused;
+        return is_paused.load(std::memory_order_relaxed);
     }
 
     std::unique_lock<std::mutex> StallProcesses() {
@@ -218,7 +217,7 @@ struct System::Impl {
     }
 
     void UnstallProcesses() {
-        if (!is_paused) {
+        if (!IsPaused()) {
             core_timing.SyncPause(false);
             kernel.Suspend(false);
         }
@@ -465,7 +464,7 @@ struct System::Impl {
     }
 
     mutable std::mutex suspend_guard;
-    bool is_paused{};
+    std::atomic_bool is_paused{};
     std::atomic<bool> is_shutting_down{};
 
     Timing::CoreTiming core_timing;

From 8fd4e44014119a1c155de64d63d455390f852a22 Mon Sep 17 00:00:00 2001
From: bunnei <bunneidev@gmail.com>
Date: Tue, 29 Nov 2022 20:32:06 -0800
Subject: [PATCH 2/2] audio_core: sink_stream: Hold the suspend lock when
 process is stalled.

- Prevents us from clashing with other callers trying to un/stall.
---
 src/audio_core/sink/sink_stream.cpp | 11 ++++++-----
 src/audio_core/sink/sink_stream.h   |  5 +++--
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/audio_core/sink/sink_stream.cpp b/src/audio_core/sink/sink_stream.cpp
index 849f862b08..67e194e3c7 100644
--- a/src/audio_core/sink/sink_stream.cpp
+++ b/src/audio_core/sink/sink_stream.cpp
@@ -266,19 +266,20 @@ void SinkStream::ProcessAudioOutAndRender(std::span<s16> output_buffer, std::siz
 }
 
 void SinkStream::Stall() {
-    if (stalled) {
+    std::scoped_lock lk{stall_guard};
+    if (stalled_lock) {
         return;
     }
-    stalled = true;
-    system.StallProcesses();
+    stalled_lock = system.StallProcesses();
 }
 
 void SinkStream::Unstall() {
-    if (!stalled) {
+    std::scoped_lock lk{stall_guard};
+    if (!stalled_lock) {
         return;
     }
     system.UnstallProcesses();
-    stalled = false;
+    stalled_lock.unlock();
 }
 
 } // namespace AudioCore::Sink
diff --git a/src/audio_core/sink/sink_stream.h b/src/audio_core/sink/sink_stream.h
index 38a4b2f517..5fea72ab72 100644
--- a/src/audio_core/sink/sink_stream.h
+++ b/src/audio_core/sink/sink_stream.h
@@ -6,6 +6,7 @@
 #include <array>
 #include <atomic>
 #include <memory>
+#include <mutex>
 #include <span>
 #include <vector>
 
@@ -240,8 +241,8 @@ private:
     f32 system_volume{1.0f};
     /// Set via IAudioDevice service calls
     f32 device_volume{1.0f};
-    /// True if coretiming has been stalled
-    bool stalled{false};
+    std::mutex stall_guard;
+    std::unique_lock<std::mutex> stalled_lock;
 };
 
 using SinkStreamPtr = std::unique_ptr<SinkStream>;