Packet Forwarding Buffer Recycling via DMA Management

The patent extracts the buffer management functionality from the Linux kernel software layer and implements it in the hardware DMA controller. The DMA controller now independently handles buffer allocation and recycling without requiring kernel intervention, thereby extracting the CPU processing burden from the packet forwarding path while maintaining the necessary buffer management functionality.

The DMA controller is enhanced to perform self-service buffer management by automatically recycling buffers that have been processed. The controller monitors packet transmission status and autonomously reallocates freed buffers for new packets without external control, enabling the system to serve itself and eliminate the need for continuous CPU involvement in buffer management.

The patent implements preliminary buffer allocation where the DMA controller pre-allocates a pool of buffers in advance. When packets arrive, the controller can immediately assign pre-prepared buffers without performing allocation operations during the critical packet forwarding path, thereby eliminating time loss associated with dynamic memory management operations.

The buffer recycling mechanism ensures continuous utilization of buffer memory resources. As soon as a buffer is freed from a completed transmission, it is immediately made available for the next packet without interruption or idle time. This continuous action eliminates the start-stop nature of buffer management and maintains steady-state throughput performance.