Implement a way to check if the command record thread is idle

Useful for debugging and testing

app/src/main/cpp/skyline/gpu/interconnect/command_executor.cpp

@@ -140,6 +140,7 @@ namespace skyline::gpu::interconnect {
             signal::SetSignalHandler({SIGINT, SIGILL, SIGTRAP, SIGBUS, SIGFPE, SIGSEGV}, signal::ExceptionalSignalHandler);
 
             incoming.Process([this, renderDocApi, &gpu](Slot *slot) {
+                idle = false;
                 VkInstance instance{*gpu.vkInstance};
                 if (renderDocApi && slot->capture)
                     renderDocApi->StartFrameCapture(RENDERDOC_DEVICEPOINTER_FROM_VKINSTANCE(instance), nullptr);
@@ -157,6 +158,7 @@ namespace skyline::gpu::interconnect {
                 }
 
                 outgoing.Push(slot);
+                idle = true;
             }, [] {});
         } catch (const signal::SignalException &e) {
             Logger::Error("{}\nStack Trace:{}", e.what(), state.loader->GetStackTrace(e.frames));
@@ -173,6 +175,10 @@ namespace skyline::gpu::interconnect {
         }
     }
 
+    bool CommandRecordThread::IsIdle() const {
+        return idle;
+    }
+
     CommandRecordThread::Slot *CommandRecordThread::AcquireSlot() {
         auto startTime{util::GetTimeNs()};
         auto slot{outgoing.Pop()};

app/src/main/cpp/skyline/gpu/interconnect/command_executor.h

@@ -68,6 +68,7 @@ namespace skyline::gpu::interconnect {
         CircularQueue<Slot *> incoming; //!< Slots pending recording
         CircularQueue<Slot *> outgoing; //!< Slots that have been submitted, may still be active on the GPU
         std::list<Slot> slots;
+        std::atomic<bool> idle;
 
         std::thread thread;
 
@@ -78,6 +79,8 @@ namespace skyline::gpu::interconnect {
       public:
         CommandRecordThread(const DeviceState &state);
 
+        bool IsIdle() const;
+
         /**
          * @return A free slot, `Reset` needs to be called before accessing it
          */