Refactor shared memory usage in blink::VEAEncoder

This CL replaces usage of deprecated base::SharedMemory with
base::UnsafeSharedMemoryRegion.

Also the CL removes media::GpuVideoAcceleratorFactories::CreateSharedMemory()
since it no longer used.

Bug: 849207
Change-Id: I6b9f2492e6e6ae5e41eb45c2268aa095cd91f49d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1916864Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Reviewed-by: Miguel Casas <mcasas@chromium.org>
Commit-Queue: Alex Ilin <alexilin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715653}

content/browser/media/android/browser_gpu_video_accelerator_factories.cc

@@ -153,11 +153,6 @@ BrowserGpuVideoAcceleratorFactories::GpuMemoryBufferManager() {
   return nullptr;
 }
 
-std::unique_ptr<base::SharedMemory>
-BrowserGpuVideoAcceleratorFactories::CreateSharedMemory(size_t size) {
-  return nullptr;
-}
-
 base::UnsafeSharedMemoryRegion
 BrowserGpuVideoAcceleratorFactories::CreateSharedMemoryRegion(size_t size) {
   return {};

content/browser/media/android/browser_gpu_video_accelerator_factories.h

@@ -48,7 +48,6 @@ class BrowserGpuVideoAcceleratorFactories
       media::VideoPixelFormat pixel_format) override;
   gpu::SharedImageInterface* SharedImageInterface() override;
   gpu::GpuMemoryBufferManager* GpuMemoryBufferManager() override;
-  std::unique_ptr<base::SharedMemory> CreateSharedMemory(size_t size) override;
   base::UnsafeSharedMemoryRegion CreateSharedMemoryRegion(size_t size) override;
   scoped_refptr<base::SingleThreadTaskRunner> GetTaskRunner() override;
   media::VideoEncodeAccelerator::SupportedProfiles

content/renderer/media/gpu/gpu_video_accelerator_factories_impl.cc

@@ -369,15 +369,6 @@ GpuVideoAcceleratorFactoriesImpl::GpuMemoryBufferManager() {
   return gpu_memory_buffer_manager_;
 }
 
-std::unique_ptr<base::SharedMemory>
-GpuVideoAcceleratorFactoriesImpl::CreateSharedMemory(size_t size) {
-  std::unique_ptr<base::SharedMemory> mem(
-      ChildThreadImpl::AllocateSharedMemory(size));
-  if (mem && !mem->Map(size))
-    return nullptr;
-  return mem;
-}
-
 base::UnsafeSharedMemoryRegion
 GpuVideoAcceleratorFactoriesImpl::CreateSharedMemoryRegion(size_t size) {
   // If necessary, this call will make a synchronous request to a privileged

content/renderer/media/gpu/gpu_video_accelerator_factories_impl.h

@@ -108,7 +108,6 @@ class CONTENT_EXPORT GpuVideoAcceleratorFactoriesImpl
   // and this class will no longer be used, as it assumes a ContextProvider is
   // present otherwise.
   void DestroyContext();
-  std::unique_ptr<base::SharedMemory> CreateSharedMemory(size_t size) override;
   base::UnsafeSharedMemoryRegion CreateSharedMemoryRegion(size_t size) override;
   scoped_refptr<base::SingleThreadTaskRunner> GetTaskRunner() override;
 

media/video/gpu_video_accelerator_factories.h

@@ -27,7 +27,6 @@
 
 namespace base {
 class SingleThreadTaskRunner;
-class SharedMemory;
 }  // namespace base
 
 namespace gfx {
@@ -125,10 +124,6 @@ class MEDIA_EXPORT GpuVideoAcceleratorFactories {
   // ShouldUseGpuMemoryBuffersForVideoFrames return false.
   virtual gpu::GpuMemoryBufferManager* GpuMemoryBufferManager() = 0;
 
-  // Allocate & return a shared memory segment.
-  virtual std::unique_ptr<base::SharedMemory> CreateSharedMemory(
-      size_t size) = 0;
-
   // Allocate & return an unsafe shared memory region
   virtual base::UnsafeSharedMemoryRegion CreateSharedMemoryRegion(
       size_t size) = 0;

media/video/mock_gpu_video_accelerator_factories.cc

@@ -115,14 +115,6 @@ MockGpuVideoAcceleratorFactories::CreateGpuMemoryBuffer(
   return ret;
 }
 
-std::unique_ptr<base::SharedMemory>
-MockGpuVideoAcceleratorFactories::CreateSharedMemory(size_t size) {
-  std::unique_ptr<base::SharedMemory> shared_memory(new base::SharedMemory);
-  if (shared_memory->CreateAndMapAnonymous(size))
-    return shared_memory;
-  return nullptr;
-}
-
 base::UnsafeSharedMemoryRegion
 MockGpuVideoAcceleratorFactories::CreateSharedMemoryRegion(size_t size) {
   return base::UnsafeSharedMemoryRegion::Create(size);

media/video/mock_gpu_video_accelerator_factories.h

@@ -19,10 +19,6 @@
 #include "services/viz/public/cpp/gpu/context_provider_command_buffer.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
-namespace base {
-class SharedMemory;
-}
-
 namespace media {
 
 class MockGpuVideoAcceleratorFactories : public GpuVideoAcceleratorFactories {
@@ -80,8 +76,6 @@ class MockGpuVideoAcceleratorFactories : public GpuVideoAcceleratorFactories {
 
   void SetGpuMemoryBuffersInUseByMacOSWindowServer(bool in_use);
 
-  std::unique_ptr<base::SharedMemory> CreateSharedMemory(size_t size) override;
-
   // Allocate & return a read-only shared memory region
   base::UnsafeSharedMemoryRegion CreateSharedMemoryRegion(size_t size) override;
 

third_party/blink/renderer/modules/mediarecorder/vea_encoder.cc

@@ -53,6 +53,10 @@ scoped_refptr<VEAEncoder> VEAEncoder::Create(
   return encoder;
 }
 
+bool VEAEncoder::OutputBuffer::IsValid() {
+  return region.IsValid() && mapping.IsValid();
+}
+
 VEAEncoder::VEAEncoder(
     const VideoTrackRecorder::OnEncodedVideoCB& on_encoded_video_callback,
     const VideoTrackRecorder::OnErrorCB& on_error_callback,
@@ -111,10 +115,12 @@ void VEAEncoder::RequireBitstreamBuffers(unsigned int /*input_count*/,
   base::queue<std::unique_ptr<InputBuffer>>().swap(input_buffers_);
 
   for (int i = 0; i < kVEAEncoderOutputBufferCount; ++i) {
-    std::unique_ptr<base::SharedMemory> shm =
-        gpu_factories_->CreateSharedMemory(output_buffer_size);
-    if (shm)
-      output_buffers_.push_back(base::WrapUnique(shm.release()));
+    auto output_buffer = std::make_unique<OutputBuffer>();
+    output_buffer->region =
+        gpu_factories_->CreateSharedMemoryRegion(output_buffer_size);
+    output_buffer->mapping = output_buffer->region.Map();
+    if (output_buffer->IsValid())
+      output_buffers_.push_back(std::move(output_buffer));
   }
 
   for (size_t i = 0; i < output_buffers_.size(); ++i)
@@ -134,11 +140,10 @@ void VEAEncoder::BitstreamBufferReady(
     num_frames_after_keyframe_ = 0;
   }
 
-  base::SharedMemory* output_buffer =
-      output_buffers_[bitstream_buffer_id].get();
-  std::string data;
-  data.append(static_cast<char*>(output_buffer->memory()),
-              metadata.payload_size_bytes);
+  OutputBuffer* output_buffer = output_buffers_[bitstream_buffer_id].get();
+  base::span<char> data_span =
+      output_buffer->mapping.GetMemoryAsSpan<char>(metadata.payload_size_bytes);
+  std::string data(data_span.begin(), data_span.end());
 
   const auto front_frame = frames_in_encode_.front();
   frames_in_encode_.pop();
@@ -168,9 +173,9 @@ void VEAEncoder::UseOutputBitstreamBufferId(int32_t bitstream_buffer_id) {
   DCHECK(encoding_task_runner_->BelongsToCurrentThread());
 
   video_encoder_->UseOutputBitstreamBuffer(media::BitstreamBuffer(
-      bitstream_buffer_id, output_buffers_[bitstream_buffer_id]->handle(),
-      false /* read_only */,
-      output_buffers_[bitstream_buffer_id]->mapped_size()));
+      bitstream_buffer_id,
+      output_buffers_[bitstream_buffer_id]->region.Duplicate(),
+      output_buffers_[bitstream_buffer_id]->region.GetSize()));
 }
 
 void VEAEncoder::FrameFinished(std::unique_ptr<InputBuffer> shm) {

third_party/blink/renderer/modules/mediarecorder/vea_encoder.h

@@ -58,6 +58,13 @@ class VEAEncoder final : public VideoTrackRecorder::Encoder,
     base::WritableSharedMemoryMapping mapping;
   };
 
+  struct OutputBuffer {
+    base::UnsafeSharedMemoryRegion region;
+    base::WritableSharedMemoryMapping mapping;
+
+    bool IsValid();
+  };
+
   VEAEncoder(
       const VideoTrackRecorder::OnEncodedVideoCB& on_encoded_video_callback,
       const VideoTrackRecorder::OnErrorCB& on_error_callback,
@@ -87,7 +94,7 @@ class VEAEncoder final : public VideoTrackRecorder::Encoder,
   std::unique_ptr<media::VideoEncodeAccelerator> video_encoder_;
 
   // Shared memory buffers for output with the VEA.
-  Vector<std::unique_ptr<base::SharedMemory>> output_buffers_;
+  Vector<std::unique_ptr<OutputBuffer>> output_buffers_;
 
   // Shared memory buffers for output with the VEA as FIFO.
   // TODO(crbug.com/960665): Replace with a WTF equivalent.