KVM: PPC: Book3S HV: Use the hardware referenced bit for kvm_age_hva
This uses the host view of the hardware R (referenced) bit to speed
up kvm_age_hva() and kvm_test_age_hva(). Instead of removing all
the relevant HPTEs in kvm_age_hva(), we now just reset their R bits
if set. Also, kvm_test_age_hva() now scans the relevant HPTEs to
see if any of them have R set.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 91b45a0..5f3c60b 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -641,6 +641,25 @@
}
EXPORT_SYMBOL_GPL(kvmppc_invalidate_hpte);
+void kvmppc_clear_ref_hpte(struct kvm *kvm, unsigned long *hptep,
+ unsigned long pte_index)
+{
+ unsigned long rb;
+ unsigned char rbyte;
+
+ rb = compute_tlbie_rb(hptep[0], hptep[1], pte_index);
+ rbyte = (hptep[1] & ~HPTE_R_R) >> 8;
+ /* modify only the second-last byte, which contains the ref bit */
+ *((char *)hptep + 14) = rbyte;
+ while (!try_lock_tlbie(&kvm->arch.tlbie_lock))
+ cpu_relax();
+ asm volatile(PPC_TLBIE(%1,%0)"; eieio; tlbsync"
+ : : "r" (rb), "r" (kvm->arch.lpid));
+ asm volatile("ptesync" : : : "memory");
+ kvm->arch.tlbie_lock = 0;
+}
+EXPORT_SYMBOL_GPL(kvmppc_clear_ref_hpte);
+
static int slb_base_page_shift[4] = {
24, /* 16M */
16, /* 64k */