nvnflinger: implement consumer abandonment

src/core/hle/service/nvnflinger/buffer_queue_consumer.cpp

@@ -175,6 +175,25 @@ Status BufferQueueConsumer::Connect(std::shared_ptr<IConsumerListener> consumer_
     return Status::NoError;
 }
 
+Status BufferQueueConsumer::Disconnect() {
+    LOG_DEBUG(Service_Nvnflinger, "called");
+
+    std::scoped_lock lock{core->mutex};
+
+    if (core->consumer_listener == nullptr) {
+        LOG_ERROR(Service_Nvnflinger, "no consumer is connected");
+        return Status::BadValue;
+    }
+
+    core->is_abandoned = true;
+    core->consumer_listener = nullptr;
+    core->queue.clear();
+    core->FreeAllBuffersLocked();
+    core->SignalDequeueCondition();
+
+    return Status::NoError;
+}
+
 Status BufferQueueConsumer::GetReleasedBuffers(u64* out_slot_mask) {
     if (out_slot_mask == nullptr) {
         LOG_ERROR(Service_Nvnflinger, "out_slot_mask may not be nullptr");

src/core/hle/service/nvnflinger/buffer_queue_consumer.h

@@ -32,6 +32,7 @@ public:
     Status AcquireBuffer(BufferItem* out_buffer, std::chrono::nanoseconds expected_present);
     Status ReleaseBuffer(s32 slot, u64 frame_number, const Fence& release_fence);
     Status Connect(std::shared_ptr<IConsumerListener> consumer_listener, bool controlled_by_app);
+    Status Disconnect();
     Status GetReleasedBuffers(u64* out_slot_mask);
 
 private:

src/core/hle/service/nvnflinger/buffer_queue_core.cpp

@@ -14,24 +14,12 @@ BufferQueueCore::BufferQueueCore() = default;
 
 BufferQueueCore::~BufferQueueCore() = default;
 
-void BufferQueueCore::NotifyShutdown() {
-    std::scoped_lock lock{mutex};
-
-    is_shutting_down = true;
-
-    SignalDequeueCondition();
-}
-
 void BufferQueueCore::SignalDequeueCondition() {
     dequeue_possible.store(true);
     dequeue_condition.notify_all();
 }
 
 bool BufferQueueCore::WaitForDequeueCondition(std::unique_lock<std::mutex>& lk) {
-    if (is_shutting_down) {
-        return false;
-    }
-
     dequeue_condition.wait(lk, [&] { return dequeue_possible.load(); });
     dequeue_possible.store(false);
 

src/core/hle/service/nvnflinger/buffer_queue_core.h

@@ -34,8 +34,6 @@ public:
     BufferQueueCore();
     ~BufferQueueCore();
 
-    void NotifyShutdown();
-
 private:
     void SignalDequeueCondition();
     bool WaitForDequeueCondition(std::unique_lock<std::mutex>& lk);
@@ -74,7 +72,6 @@ private:
     u32 transform_hint{};
     bool is_allocating{};
     mutable std::condition_variable_any is_allocating_condition;
-    bool is_shutting_down{};
 };
 
 } // namespace Service::android

src/core/hle/service/nvnflinger/consumer_base.cpp

@@ -27,6 +27,26 @@ void ConsumerBase::Connect(bool controlled_by_app) {
     consumer->Connect(shared_from_this(), controlled_by_app);
 }
 
+void ConsumerBase::Abandon() {
+    LOG_DEBUG(Service_Nvnflinger, "called");
+
+    std::scoped_lock lock{mutex};
+
+    if (!is_abandoned) {
+        this->AbandonLocked();
+        is_abandoned = true;
+    }
+}
+
+void ConsumerBase::AbandonLocked() {
+    for (int i = 0; i < BufferQueueDefs::NUM_BUFFER_SLOTS; i++) {
+        this->FreeBufferLocked(i);
+    }
+    // disconnect from the BufferQueue
+    consumer->Disconnect();
+    consumer = nullptr;
+}
+
 void ConsumerBase::FreeBufferLocked(s32 slot_index) {
     LOG_DEBUG(Service_Nvnflinger, "slot_index={}", slot_index);
 

src/core/hle/service/nvnflinger/consumer_base.h

@@ -24,6 +24,7 @@ class BufferQueueConsumer;
 class ConsumerBase : public IConsumerListener, public std::enable_shared_from_this<ConsumerBase> {
 public:
     void Connect(bool controlled_by_app);
+    void Abandon();
 
 protected:
     explicit ConsumerBase(std::unique_ptr<BufferQueueConsumer> consumer_);
@@ -34,6 +35,7 @@ protected:
     void OnBuffersReleased() override;
     void OnSidebandStreamChanged() override;
 
+    void AbandonLocked();
     void FreeBufferLocked(s32 slot_index);
     Status AcquireBufferLocked(BufferItem* item, std::chrono::nanoseconds present_when);
     Status ReleaseBufferLocked(s32 slot, const std::shared_ptr<GraphicBuffer>& graphic_buffer);

src/core/hle/service/nvnflinger/nvnflinger.cpp

@@ -47,7 +47,10 @@ void Nvnflinger::SplitVSync(std::stop_token stop_token) {
         vsync_signal.Wait();
 
         const auto lock_guard = Lock();
-        Compose();
+
+        if (!is_abandoned) {
+            Compose();
+        }
     }
 }
 
@@ -98,7 +101,6 @@ Nvnflinger::~Nvnflinger() {
     }
 
     ShutdownLayers();
-    vsync_thread = {};
 
     if (nvdrv) {
         nvdrv->Close(disp_fd);
@@ -106,12 +108,20 @@ Nvnflinger::~Nvnflinger() {
 }
 
 void Nvnflinger::ShutdownLayers() {
-    const auto lock_guard = Lock();
-    for (auto& display : displays) {
-        for (size_t layer = 0; layer < display.GetNumLayers(); ++layer) {
-            display.GetLayer(layer).Core().NotifyShutdown();
+    // Abandon consumers.
+    {
+        const auto lock_guard = Lock();
+        for (auto& display : displays) {
+            for (size_t layer = 0; layer < display.GetNumLayers(); ++layer) {
+                display.GetLayer(layer).GetConsumer().Abandon();
+            }
         }
+
+        is_abandoned = true;
     }
+
+    // Join the vsync thread, if it exists.
+    vsync_thread = {};
 }
 
 void Nvnflinger::SetNVDrvInstance(std::shared_ptr<Nvidia::Module> instance) {

src/core/hle/service/nvnflinger/nvnflinger.h

@@ -140,6 +140,8 @@ private:
 
     s32 swap_interval = 1;
 
+    bool is_abandoned = false;
+
     /// Event that handles screen composition.
     std::shared_ptr<Core::Timing::EventType> multi_composition_event;
     std::shared_ptr<Core::Timing::EventType> single_composition_event;