ARC: mm: tlb flush optim: elide repeated uTLB invalidate in loop

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The unconditional full TLB flush (on say ASID rollover) iterates over each
entry and uses TLBWrite to zero it out. TLBWrite by design also invalidates
the uTLBs thus we end up invalidating it as many times as numbe rof
entries (512 or 1k)

Optimize this by using a weaker TLBWriteNI cmd in loop, which doesn't
tinker with uTLBs and an explicit one time IVUTLB, outside the loop to
invalidate them all once.

And given the optimiztion, the IVUTLB is now needed on MMUv4 too where
the uTLBs and JTLBs are otherwise coherent given the TLBInsertEntry /
TLBDeleteEntry commands

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

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This commit is contained in:

Vineet Gupta 2015-10-17 16:54:14 +05:30

parent ad4c40e937

commit 1355ea2e60

1 changed files with 29 additions and 45 deletions

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arch/arc/mm/tlb.c

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