Method and device for preventing first input first output (FIFO) queue from overflowing

Abstract

The invention provides a method for preventing a first input first output (FIFO) queue from overflowing. The method comprises the following steps of: A, establishing a first BD (buffer descriptor) ring and a second BD ring in a device memory; B, writing data in the FIFO in an idle BD in a first BD ring through a first write pointer by a hardware transceiver, and producing a receiving interruption by the hardware transceiver after the write-in; C, reading the data from the first BD ring by using a first read pointer after driving software detects the receiving interruption; writing the read data in the second BD ring by using a second write pointer by a driving software; reading the data from the second BD ring by using a second read pointer and processing the data by the driving software. By the scheme of the invention, the FIFO can be prevented from overflowing on the premise that the hardware transceiver is not modified; correspondingly, the driving receiving stability and reliability can be improved.

Description

technical field [0001] The invention relates to the technical field of data communication, in particular to a receiving mechanism of device driver software, and in particular to a method and device for avoiding overflow of a first-in-first-out queue. Background technique [0002] Currently, in network devices, the device driver software generally adopts a buffer descriptor (BD) ring mechanism for receiving data, and the BD ring is a data buffer between the driver software and the hardware transceiver. Such as figure 1 As shown, BD 104 is allocated in device memory 103. Each BD 104 is composed of a status flag and a buffer pointer. The status flag indicates whether the BD is idle or has data to be processed. The buffer pointer points to a memory area for storing pending processed data. Multiple BDs 104 connected end to end form a BD ring. The BD ring is a data buffer between the driver software 101 and the hardware transceiver 102 . [0003] When the device is initialized...

AI Technical Summary

Problems solved by technology

However, if the FIFO overflows repeatedly, a large number of additional interrupts will be generated, further increasing the overhead of the driver software system, reducing the processing performance of the driver software, and forming a vicious circle

In addition, some hardware transceivers will cause internal state machine disorder after the FIFO overflows multiple times. In mild cases, data will no longer be received, and in severe cases, data will be written to wrong memory addresses, resulting in system crashes.

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