[WebGPU] Queue::commitMTLCommandBuffer will fail if command buffer wa…

…s already committed

https://bugs.webkit.org/show_bug.cgi?id=264339
<radar://117851924>

Reviewed by Tadeu Zagallo.

Ensure that a command buffer doesn't get submitted twice and generate
a validation error if we would attempt to do so.

* Source/WebGPU/WebGPU/CommandBuffer.h:
* Source/WebGPU/WebGPU/CommandBuffer.mm:
(WebGPU::CommandBuffer::makeInvalid):
* Source/WebGPU/WebGPU/Queue.h:
* Source/WebGPU/WebGPU/Queue.mm:
(WebGPU::Queue::validateSubmit const):
(WebGPU::Queue::commitMTLCommandBuffer):
(WebGPU::Queue::submit):
(wgpuQueueSubmit):

Canonical link: https://commits.webkit.org/270361@main

Source/WebGPU/WebGPU/CommandBuffer.h

@@ -58,12 +58,13 @@ class CommandBuffer : public WGPUCommandBufferImpl, public RefCounted<CommandBuf
     id<MTLCommandBuffer> commandBuffer() const { return m_commandBuffer; }
 
     Device& device() const { return m_device; }
+    void makeInvalid();
 
 private:
     CommandBuffer(id<MTLCommandBuffer>, Device&);
     CommandBuffer(Device&);
 
-    const id<MTLCommandBuffer> m_commandBuffer { nil };
+    id<MTLCommandBuffer> m_commandBuffer { nil };
 
     const Ref<Device> m_device;
 };

Source/WebGPU/WebGPU/CommandBuffer.mm

@@ -48,6 +48,11 @@
     m_commandBuffer.label = label;
 }
 
+void CommandBuffer::makeInvalid()
+{
+    m_commandBuffer = nil;
+}
+
 } // namespace WebGPU
 
 #pragma mark WGPU Stubs

Source/WebGPU/WebGPU/Queue.h

@@ -59,7 +59,7 @@ class Queue : public WGPUQueueImpl, public ThreadSafeRefCounted<Queue> {
     ~Queue();
 
     void onSubmittedWorkDone(CompletionHandler<void(WGPUQueueWorkDoneStatus)>&& callback);
-    void submit(Vector<std::reference_wrapper<const CommandBuffer>>&& commands);
+    void submit(Vector<std::reference_wrapper<CommandBuffer>>&& commands);
     void writeBuffer(const Buffer&, uint64_t bufferOffset, const void* data, size_t);
     void writeTexture(const WGPUImageCopyTexture& destination, const void* data, size_t dataSize, const WGPUTextureDataLayout&, const WGPUExtent3D& writeSize);
     void setLabel(String&&);
@@ -78,7 +78,7 @@ class Queue : public WGPUQueueImpl, public ThreadSafeRefCounted<Queue> {
     Queue(id<MTLCommandQueue>, Device&);
     Queue(Device&);
 
-    bool validateSubmit(const Vector<std::reference_wrapper<const CommandBuffer>>&) const;
+    bool validateSubmit(const Vector<std::reference_wrapper<CommandBuffer>>&) const;
     bool validateWriteBuffer(const Buffer&, uint64_t bufferOffset, size_t) const;
 
     void ensureBlitCommandEncoder();

Source/WebGPU/WebGPU/Queue.mm

@@ -121,7 +121,7 @@
     callbacks.append(WTFMove(completionHandler));
 }
 
-bool Queue::validateSubmit(const Vector<std::reference_wrapper<const CommandBuffer>>& commands) const
+bool Queue::validateSubmit(const Vector<std::reference_wrapper<CommandBuffer>>& commands) const
 {
     for (auto command : commands) {
         if (!isValidToUseWith(command.get(), *this))
@@ -140,6 +140,9 @@
 
 void Queue::commitMTLCommandBuffer(id<MTLCommandBuffer> commandBuffer)
 {
+    if (!commandBuffer || commandBuffer.status >= MTLCommandBufferStatusCommitted)
+        return;
+
     ASSERT(commandBuffer.commandQueue == m_commandQueue);
     [commandBuffer addScheduledHandler:[protectedThis = Ref { *this }](id<MTLCommandBuffer>) {
         protectedThis->scheduleWork(CompletionHandler<void(void)>([protectedThis = protectedThis.copyRef()]() {
@@ -162,7 +165,7 @@
     ++m_submittedCommandBufferCount;
 }
 
-void Queue::submit(Vector<std::reference_wrapper<const CommandBuffer>>&& commands)
+void Queue::submit(Vector<std::reference_wrapper<CommandBuffer>>&& commands)
 {
     // https://gpuweb.github.io/gpuweb/#dom-gpuqueue-submit
 
@@ -173,8 +176,20 @@
 
     finalizeBlitCommandEncoder();
 
-    for (auto commandBuffer : commands)
-        commitMTLCommandBuffer(commandBuffer.get().commandBuffer());
+    NSMutableArray<id<MTLCommandBuffer>> *commandBuffersToSubmit = [NSMutableArray arrayWithCapacity:commands.size()];
+    for (auto commandBuffer : commands) {
+        auto& command = commandBuffer.get();
+        if (id<MTLCommandBuffer> mtlBuffer = command.commandBuffer())
+            [commandBuffersToSubmit addObject:mtlBuffer];
+        else {
+            m_device.generateAValidationError("Command buffer appears twice."_s);
+            return;
+        }
+        command.makeInvalid();
+    }
+
+    for (id<MTLCommandBuffer> commandBuffer in commandBuffersToSubmit)
+        commitMTLCommandBuffer(commandBuffer);
 
     if ([MTLCaptureManager sharedCaptureManager].isCapturing)
         [[MTLCaptureManager sharedCaptureManager] stopCapture];
@@ -616,7 +631,7 @@ void wgpuQueueOnSubmittedWorkDoneWithBlock(WGPUQueue queue, WGPUQueueWorkDoneBlo
 
 void wgpuQueueSubmit(WGPUQueue queue, size_t commandCount, const WGPUCommandBuffer* commands)
 {
-    Vector<std::reference_wrapper<const WebGPU::CommandBuffer>> commandsToForward;
+    Vector<std::reference_wrapper<WebGPU::CommandBuffer>> commandsToForward;
     for (uint32_t i = 0; i < commandCount; ++i)
         commandsToForward.append(WebGPU::fromAPI(commands[i]));
     WebGPU::fromAPI(queue).submit(WTFMove(commandsToForward));