ppcmu: Use generational flush for PAT entries - #199
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`TLBEntry` and its cache constants and flags are used exclusively by ppcmmu.cpp. Keep them out of the public MMU header so future TLB changes do not expand its interface. This required a small fix in dbdma.cpp since it was implicitly relying on an include that we removed. Also declare `gTLBFlush*` variables as static to make it explicit that we don't expect them to be accessed outside of ppcmmu.cpp.
We end up flushing all entries very frequently (hundreds of thousands of times during Mac OS X boot), and were spending a lot of time in `tlb_flush_entries` walking through the array. We can instead store a generation counter and make invalidation be a simple increment. This does make validity checks slightly more expensive, but it appears to be a net win. On my machine it takes booting the Mac OS X public meta to the Finder from ~58 seconds to ~35 seconds.
mihaip
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Includes dingusdev/dingusppc#199 which significantly speeds up Mac OS X boot time. For #219
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We end up flushing all entries very frequently (hundreds of thousands of times during Mac OS X boot), and were spending a lot of time in
tlb_flush_entrieswalking through the array. We can instead store a generation counter and make invalidation be a simple increment. This does make validity checks slightly more expensive, but it appears to be a net win. On my machine it takes booting the Mac OS X public meta to the Finder from ~58 seconds to ~35 seconds.To hide these implemetation details we first do a preparatory refactor to move
TLBEntryand related code into ppcmmu.cpp - it didn't actually need to be in the header file.