'mask' is always a constant, so we can check whether it includes a bit that might be owned by the guest very cheaply, and avoid the decache call. Saves a few hundred bytes of module text. Signed-off-by: Avi Kivity <avi@xxxxxxxxxx> --- arch/x86/kvm/kvm_cache_regs.h | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h index 6b419a3..5a109c6 100644 --- a/arch/x86/kvm/kvm_cache_regs.h +++ b/arch/x86/kvm/kvm_cache_regs.h @@ -1,6 +1,9 @@ #ifndef ASM_KVM_CACHE_REGS_H #define ASM_KVM_CACHE_REGS_H +#define KVM_POSSIBLE_CR0_GUEST_BITS X86_CR0_TS +#define KVM_POSSIBLE_CR4_GUEST_BITS X86_CR4_PGE + static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, enum kvm_reg reg) { @@ -40,7 +43,8 @@ static inline u64 kvm_pdptr_read(struct kvm_vcpu *vcpu, int index) static inline ulong kvm_read_cr0_bits(struct kvm_vcpu *vcpu, ulong mask) { - if (mask & vcpu->arch.cr0_guest_owned_bits) + ulong tmask = mask & KVM_POSSIBLE_CR0_GUEST_BITS; + if (tmask & vcpu->arch.cr0_guest_owned_bits) kvm_x86_ops->decache_cr0_guest_bits(vcpu); return vcpu->arch.cr0 & mask; } @@ -52,7 +56,8 @@ static inline ulong kvm_read_cr0(struct kvm_vcpu *vcpu) static inline ulong kvm_read_cr4_bits(struct kvm_vcpu *vcpu, ulong mask) { - if (mask & vcpu->arch.cr4_guest_owned_bits) + ulong tmask = mask & KVM_POSSIBLE_CR4_GUEST_BITS; + if (tmask & vcpu->arch.cr4_guest_owned_bits) kvm_x86_ops->decache_cr4_guest_bits(vcpu); return vcpu->arch.cr4 & mask; } -- 1.6.5.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html