Ring Controller for PCIe Message Handling

摘要

A system that includes a PCIe hierarchy may utilize a ring controller for message handling. Nodes acting as the root complex or as endpoint devices may include such ring controllers, portions of which may be implemented by dedicated circuitry on each node. The ring controllers may receive posted transactions representing messages, may return flow control credits for those transactions, may classify each message as to its type, and may write information about each message to a respective ring buffer storing information about messages of that type. A processor (or processing logic/circuitry) on the node may subsequently retrieve messages from the ring buffers and process them. The sizes and locations of the ring buffers in memory may be configurable by software (e.g., by writing to registers within the ring controllers). The message types may include correctable and non-correctable error messages, and non-error messages (including, but not limited to, vendor-defined messages).

主权项

1. An apparatus, comprising:
a processor; a memory comprising program instructions that when executed on the processor causes the processor to perform at least a portion of an application; a network interface that connects the apparatus to a switched fabric hierarchy; and a ring controller; wherein, during execution of the application, the ring controller is configured to:
receive one or more posted transactions, each representing a message;determine, for one of the posted transactions, a type for the message, wherein the determined type is one of a plurality of message types supported by the switched fabric hierarchy; andstore, for the one of the posted transactions, information about the message in a data structure that is configured to store information about a plurality of messages of the determined type; and wherein, during execution of the application and subsequent to the information about the message being stored in the data structure, the processor is configured to:
retrieve the information about the message from the data structure; andprocess the message.