Intel Corporation
PCI EXPRESS CHAIN DESCRIPTORS

Abstract:

There is disclosed a computing apparatus, including: a hardware platform; an interface to a computer expansion bus; logic configured to operate on the hardware platform to: provision an unshaded memory queue, including a dedicated memory window for the computer expansion bus; and provision a descriptor ring, the descriptor ring configured to receive a descriptor, identify the descriptor as a chain descriptor targeted to a descriptor chain, identify a general descriptor unit (GDU) of the chain descriptor as having a device identifier (DID) matching the computing apparatus, process a workload of the GDU according to a private data field of the GDU, and forward the chain descriptor to a next-hop device via a switch fabric of the computer expansion bus, including bypassing a root complex of the computer expansion bus.