diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2015-03-12 18:16:51 +0000 |
|---|---|---|
| committer | Christoffer Dall <christoffer.dall@linaro.org> | 2015-03-12 22:34:43 +0100 |
| commit | 35307b9a5f7ebcc8d8db41c73b69c131b48ace2b (patch) | |
| tree | 42cf3a7b7177139fe59d764893e0556487b5ba72 /arch/arm/include | |
| parent | 1d2ebaccc741a299abfafb848414b01d190f4e33 (diff) | |
arm/arm64: KVM: Implement Stage-2 page aging
Until now, KVM/arm didn't care much for page aging (who was swapping
anyway?), and simply provided empty hooks to the core KVM code. With
server-type systems now being available, things are quite different.
This patch implements very simple support for page aging, by clearing
the Access flag in the Stage-2 page tables. On access fault, the current
fault handling will write the PTE or PMD again, putting the Access flag
back on.
It should be possible to implement a much faster handling for Access
faults, but that's left for a later patch.
With this in place, performance in VMs is degraded much more gracefully.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Diffstat (limited to 'arch/arm/include')
| -rw-r--r-- | arch/arm/include/asm/kvm_arm.h | 1 | ||||
| -rw-r--r-- | arch/arm/include/asm/kvm_host.h | 13 |
2 files changed, 3 insertions, 11 deletions
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index 816db0bf2dd8..d995821f1698 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -185,6 +185,7 @@ #define HSR_COND (0xfU << HSR_COND_SHIFT) #define FSC_FAULT (0x04) +#define FSC_ACCESS (0x08) #define FSC_PERM (0x0c) /* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */ diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 902a7d1441ae..d71607c16601 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -167,19 +167,10 @@ void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu); int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices); +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end); +int kvm_test_age_hva(struct kvm *kvm, unsigned long hva); /* We do not have shadow page tables, hence the empty hooks */ -static inline int kvm_age_hva(struct kvm *kvm, unsigned long start, - unsigned long end) -{ - return 0; -} - -static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) -{ - return 0; -} - static inline void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm, unsigned long address) { |