RdmaGpuBuffer.hpp File Reference

Vendor-neutral allocator of RDMA-capable GPU VRAM. More...

Detailed Description

Vendor-neutral allocator of RDMA-capable GPU VRAM.

The counterpart to HostPinnedRing for true GPU-direct access: where HostPinnedRing hands a card a page-locked host buffer, RdmaGpuBuffer hands it a slot of GPU VRAM the card can DMA into/out of directly (GPUDirect RDMA). Each slot exposes the per-API handoff the card's SDK wants:

• CUDA : a CUdeviceptr (BAR1-mappable, gpuDirectRDMACapable) — reuses CudaVmmAllocator.
• Vulkan : the VkRemoteAddressNV from VK_NV_external_memory_rdma — reuses vkinterop::createRdmaBuffer.
• D3D12 : the GPU VA from NvAPI_D3D12_CreateCommittedRDMABuffer — gated on SCORE_HAS_NVAPI (off unless an NvAPI SDK is configured).
• Host : a 64 KiB-aligned host pointer — the non-RDMA fallback (the card's app-buffer path with RDMA disabled).

This is the allocator only. Wrapping a slot as a QRhi resource for the encoder/decoder to render into/sample from is the consumer's concern (the vendor backend, e.g. Deltacast). The first consumer is Deltacast's VHD_CreateSlotEx(RDMAEnabled=TRUE), which takes exactly {pBuffer=gpuVA, ctx}.

Go to the source code of this file.

Classes
struct	score::gfx::interop::RdmaGpuSlot
	One allocated slot. gpuVA is the per-API handoff the card's SDK wants. More...
struct	score::gfx::interop::RdmaGpuBufferConfig
class	score::gfx::interop::RdmaGpuBuffer
	Owns N RDMA-capable GPU buffers. Move-only; destroy() is idempotent. More...

Namespaces
namespace	score
	Base toolkit upon which the software is built.
namespace	score::gfx
	Graphics rendering pipeline for ossia score.

Enumerations
enum class	score::gfx::interop::RdmaGpuApi : std::uint8_t {   None = 0 , Cuda , Vulkan , D3D12 ,   HostFallback }
	Which allocation mechanism a RdmaGpuBuffer instance uses. More...

Enumeration Type Documentation

RdmaGpuApi

enum class score::gfx::interop::RdmaGpuApi : std::uint8_t

strong

Which allocation mechanism a RdmaGpuBuffer instance uses.

Enumerator
Cuda	CUDA VMM (CUdeviceptr); reuses CudaVmmAllocator.
Vulkan	VK_NV_external_memory_rdma (remote address).
D3D12	NvAPI CreateCommittedRDMABuffer (GPU VA). SCORE_HAS_NVAPI.
HostFallback	64 KiB-aligned host memory (non-RDMA app-buffer path).