GitLab

This is a reland of 09825450

No changes are made to the original CL. The original change was reverted
because "Cast Audio Linux" was failing to build [1]. It looks like this
happened not because of the change but because
//media/gpu/chromeos/BUILD.gn was taking effect in Chromecast
unintentionally which triggered an assert in one of the dependencies. The
root cause was that use_vaapi was getting set to true for Chromecast and
this is fixed by [2].

[1] https://ci.chromium.org/ui/p/chromium/builders/ci/Cast%20Audio%20Linux/92923/overview
[2] https://chromium-review.googlesource.com/c/chromium/src/+/2580449

Original change's description:
> media/platform_vf_utils: Handle null GMB factory.
>
> This CL handles a null GpuMemoryBufferFactory in
> AllocateGpuMemoryBufferHandle() so that the caller is not obligated to
> pass a valid factory. This is in preparation for follow-ups CLs to
> remove the need for video encode accelerators to have access to a
> GpuMemoryBufferFactory.
>
> When the GpuMemoryBufferFactory is null, we just use the render node
> directly to allocate a native buffer object and then we wrap it into a
> GpuMemoryBufferHandle.
>
> So, why do we still keep the option to have a non-null
> GpuMemoryBufferFactory? This is because that path is still useful in the
> decoding case: when a buffer is created with the GpuMemoryBufferFactory,
> the corresponding NativePixmap is cached [1]; eventually, a SharedImage
> needs to be created and to do so we pass the GpuMemoryBufferHandle
> obtained from the factory [2]; when the SharedImage system needs to
> create the GLImage for the buffer, it passes the handle to the
> factory [3] which in turn uses it to look up the cached
> NativePixmap [4]. This saves us from going through a gbm_bo_import()
> (which also implies a thread hop to the DRM thread).
>
> So, in conclusion, for buffers that need to be displayed later, it's
> still better to use the GMB factory owned by the GpuServiceImpl. For
> encoders this is not the case.
>
> [1] https://source.chromium.org/chromium/chromium/src/+/master:gpu/ipc/service/gpu_memory_buffer_factory_native_pixmap.cc;l=319;drc=d81c5852498699fe3cd812e78d31c77c28e29281
> [2] https://source.chromium.org/chromium/chromium/src/+/master:media/gpu/chromeos/mailbox_video_frame_converter.cc;l=355-359;drc=d81c5852498699fe3cd812e78d31c77c28e29281
> [3] https://source.chromium.org/chromium/chromium/src/+/master:gpu/command_buffer/service/shared_image_backing_gl_texture.cc;l=355-356;drc=d81c5852498699fe3cd812e78d31c77c28e29281
> [4] https://source.chromium.org/chromium/chromium/src/+/master:gpu/ipc/service/gpu_memory_buffer_factory_native_pixmap.cc;l=164-172;drc=d81c5852498699fe3cd812e78d31c77c28e29281
>
> Bug: b:173167846
> Test: video.EncodeAccel.h264_720p_nv12_dmabuf on elm
> Change-Id: I7b730eb843da7503c61bffe30dce7a5ce51dec60
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2568937
> Commit-Queue: Andres Calderon Jaramillo <andrescj@chromium.org>
> Reviewed-by: Miguel Casas <mcasas@chromium.org>
> Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#834608}

Bug: b:173167846
Change-Id: I88b4849b01de86e7f2783db22561e8160a1f7a6b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2579646Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Miguel Casas <mcasas@chromium.org>
Commit-Queue: Andres Calderon Jaramillo <andrescj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#835009}