kvm: arm/arm64: Rework gpa callback handlers

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In order to perform an operation on a gpa range, we currently iterate
over each page in a user memory slot for the given range. This is
inefficient while dealing with a big range (e.g, a VMA), especially
while unmaping a range. At present, with stage2 unmap on a range with
a hugepage backed region, we clear the PMD when we unmap the first
page in the loop. The remaining iterations simply traverse the page table
down to the PMD level only to see that nothing is in there.

This patch reworks the code to invoke the callback handlers on the
biggest range possible within the memory slot to to reduce the number of
times the handler is called.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>

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Suzuki K Poulose 2017-03-20 18:26:42 +00:00 • committed by Christoffer Dall

parent 97da3854c5

commit 056aad67f8

1 changed files with 13 additions and 18 deletions

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arch/arm/kvm/mmu.c

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