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kvm: mmu: Used range based flushing in slot_handle_level_range

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Replace kvm_flush_remote_tlbs with kvm_flush_remote_tlbs_with_address
in slot_handle_level_range. When range based flushes are not enabled
kvm_flush_remote_tlbs_with_address falls back to kvm_flush_remote_tlbs.

This changes the behavior of many functions that indirectly use
slot_handle_level_range, iff the range based flushes are enabled. The
only potential problem I see with this is that kvm->tlbs_dirty will be
cleared less often, however the only caller of slot_handle_level_range that
checks tlbs_dirty is kvm_mmu_notifier_invalidate_range_start which
checks it and does a kvm_flush_remote_tlbs after calling
kvm_unmap_hva_range anyway.

Tested: Ran all kvm-unit-tests on a Intel Haswell machine with and
	without this patch. The patch introduced no new failures.

Signed-off-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Ben Gardon 2019-03-12 11:45:59 -07:00 committed by Paolo Bonzini
parent 3d9683cf3b
commit f285c633cb
1 changed files with 5 additions and 2 deletions
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7
arch/x86/kvm/mmu.c
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@ -5526,7 +5526,9 @@ slot_handle_level_range(struct kvm *kvm, struct kvm_memory_slot *memslot,
if (need_resched() || spin_needbreak(&kvm->mmu_lock)) {
if (flush && lock_flush_tlb) {
kvm_flush_remote_tlbs(kvm);
kvm_flush_remote_tlbs_with_address(kvm,
start_gfn,
iterator.gfn - start_gfn + 1);
flush = false;
}
cond_resched_lock(&kvm->mmu_lock);
@ -5534,7 +5536,8 @@ slot_handle_level_range(struct kvm *kvm, struct kvm_memory_slot *memslot,
}
if (flush && lock_flush_tlb) {
kvm_flush_remote_tlbs(kvm);
kvm_flush_remote_tlbs_with_address(kvm, start_gfn,
end_gfn - start_gfn + 1);
flush = false;
}