Quoting Chris Wilson (2018-04-12 14:57:42)
> Quoting Mika Kuoppala (2018-04-12 14:52:37)
> > Read ordering on cpu can be out of order and speculative.
> If it didn't include a barrier to prevent compiler mispeculation. rmb()
> only applies to other CPU cores and not the GPU so this is entirely
To put it another way this is just imposing the cost of an uncached
mmio which the entire point of using HWSP in the first place is to
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