hm, do we know it for a fact that the 40% AIM regression is due to the
fastpath overhead of the BKL? It would be extraordinary if so.
I think it is far more likely that it's due to the different scheduling
and wakeup behavior of the new kernel/semaphore.c code. So the fix would
be to restore the old scheduling behavior - that's what Yanmin's manual
revert did and that's what got him back the previous AIM7 performance.
Ingo
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