tree 57015afdcfc6e4affb1700444bd7a3c38ebd7a83
parent 47d7c80dc788a7354a706d3fe0862a1c21ecb566
author Iago Toral Quiroga <itoral@igalia.com> 1562235760 +0200
committer Iago Toral Quiroga <itoral@igalia.com> 1562915798 +0200

v3d: acquire scoreboard lock before first tlb read

Until now we have always been emitting our scoreboard locks on the last thread
switch to improve parallelism. We did this by emitting our last thread switch
right before our tlb writes at the very end of the program, where we know that
we are outside control flow.

Unfortunately, this strategy is not valid when we have tlb color reads too, as
these will happen before this point in the program and can happen inside
control flow.

To fix this we always emit a thread switch before the first tlb load and if we
see additional thread switches after that point, we change the strategy to lock
on the first thread switch.

v2: change the solution so it is expected to work in more scenarios (Eric).

Reviewed-by: Eric Anholt <eric@anholt.net>