Why no cuda sync?

[voldemortX]

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Hello, I have a coding question, why there is no cuda synchronization here? Don't we need the previous kernel to complete before executing the next one?

https://github.com/ApolloAuto/apollo/blob/803170c79e5ef12bafd0adb1b39273b576e4589a/modules/perception/lidar_detection/detector/point_pillars_detection/preprocess_points_cuda.cu#L179