Jetson TX2's digital signal processing performance

for example FFT,IIR,FIR and so on.

You would need to run cuFFT library, there are some samples included in CUDA toolkit. The IIR/FIR implementation would presumably need provided using CUDA kernel. In addition to cuFFT, you could consult NPP Signal Primitives (NVIDIA Performance Primitives) for CUDA-accelerated convolution filtering.