Fixed deadlock in sgmv_shrink kernel caused by imbalanced segments #156
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Fixes #149.
The crux of the issue was that each grid block can execute a dynamic number of steps depending on the size of its segment (
s_end - s_start). However, during each step the block will callgrid.sync(). If one block executes more steps than another, it will callgrid.sync()a different number of times, leading to a deadlock.The solution presented here is to compute the max number of steps from the largest segment, and then call
grid.sync()at the end of the kernel for the difference between the max steps and the current block's steps.