Common Deadlock Scenarios - 2023.2 English

Vitis Tutorials: AI Engine (XD100)

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2023.2 English

A deadlock is usually caused by insufficient FIFOs, or the access rate not matching between multiple FIFOs (or different branches of the same net in stream multicast). The following figure shows some deadlock scenarios:

Deadlock Scenarios

Scenario 1: This scenario occurs when K1 tries to write to FIFO0, but the FIFO is full. K2 is still waiting for data coming from FIFO1 before consuming data from FIFO0.

Scenario 2: This scenario occurs when NET0 multicasts to multiple destinations, and the destinations are connected by stream or cascade stream (FIFO1). The NET0 branch 1 is full because K2 is waiting for data from FIFO1, but K1 is still hungry for data from NET0 branch 0 to produce data for FIFO1.

Scenario 3: This scenario occurs when K1 and K2 are connected by buffers (including RTP buffers) and streams. When K1 is trying to write data to K2 using FIFO0, K2 is still trying to acquire lock for the ping or pong buffer. K1 will not release the lock of the buffer until it finishes its current iteration.