diff mbox series

[5/7] KVM: arm/arm64: Elide both CMOs and TBLIs on freeing the whole Stage-2

Message ID 20191213182503.14460-6-maz@kernel.org (mailing list archive)
State New, archived
Headers show
Series KVM: arm/arm64: Help VMs dying quicker | expand

Commit Message

Marc Zyngier Dec. 13, 2019, 6:25 p.m. UTC 
When freeing the whole of a VM's Stage-2 page tables, there is
little point in doing cache maintenance on each and every page
(the guest won't be running anymore, let alone having its MMU
off). As for TLBs, there is no point in invalidating individual
pages, as we can replace the whole thing with a VMALL operation,
which invalidates all the TLBs for this VM in one go.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 virt/kvm/arm/mmu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 4399866842dc..d7c710491d26 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -1016,10 +1016,13 @@  void kvm_free_stage2_pgd(struct kvm *kvm)
 
 	spin_lock(&kvm->mmu_lock);
 	if (kvm->arch.pgd) {
-		unmap_stage2_range(kvm, 0, kvm_phys_size(kvm), 0);
+		unmap_stage2_range(kvm, 0, kvm_phys_size(kvm),
+				   KVM_UNMAP_ELIDE_CMO | KVM_UNMAP_ELIDE_TBLI);
 		pgd = READ_ONCE(kvm->arch.pgd);
 		kvm->arch.pgd = NULL;
 		kvm->arch.pgd_phys = 0;
+
+		kvm_flush_remote_tlbs(kvm);
 	}
 	spin_unlock(&kvm->mmu_lock);