aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/include/asm
diff options
context:
space:
mode:
authorPaul Mackerras <paulus@samba.org>2012-11-19 22:52:49 +0000
committerAlexander Graf <agraf@suse.de>2012-12-06 01:33:54 +0100
commit44e5f6be62741bd44968f40f3afa1cff1df983f2 (patch)
tree82476ebfb27757ed9ad146ab4ef5d072e58629a8 /arch/powerpc/include/asm
parent4879f241720cda3e6c18a1713bf9b2ed2de14ee4 (diff)
KVM: PPC: Book3S HV: Add a mechanism for recording modified HPTEs
This uses a bit in our record of the guest view of the HPTE to record when the HPTE gets modified. We use a reserved bit for this, and ensure that this bit is always cleared in HPTE values returned to the guest. The recording of modified HPTEs is only done if other code indicates its interest by setting kvm->arch.hpte_mod_interest to a non-zero value. The reason for this is that when later commits add facilities for userspace to read the HPT, the first pass of reading the HPT will be quicker if there are no (or very few) HPTEs marked as modified, rather than having most HPTEs marked as modified. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'arch/powerpc/include/asm')
-rw-r--r--arch/powerpc/include/asm/kvm_book3s_64.h9
-rw-r--r--arch/powerpc/include/asm/kvm_host.h1
2 files changed, 10 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index 1472a5b4e4e..b322e5bd696 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -50,6 +50,15 @@ extern int kvm_hpt_order; /* order of preallocated HPTs */
#define HPTE_V_HVLOCK 0x40UL
#define HPTE_V_ABSENT 0x20UL
+/*
+ * We use this bit in the guest_rpte field of the revmap entry
+ * to indicate a modified HPTE.
+ */
+#define HPTE_GR_MODIFIED (1ul << 62)
+
+/* These bits are reserved in the guest view of the HPTE */
+#define HPTE_GR_RESERVED HPTE_GR_MODIFIED
+
static inline long try_lock_hpte(unsigned long *hpte, unsigned long bits)
{
unsigned long tmp, old;
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 3093896015f..58c72646c44 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -248,6 +248,7 @@ struct kvm_arch {
atomic_t vcpus_running;
unsigned long hpt_npte;
unsigned long hpt_mask;
+ atomic_t hpte_mod_interest;
spinlock_t slot_phys_lock;
unsigned short last_vcpu[NR_CPUS];
struct kvmppc_vcore *vcores[KVM_MAX_VCORES];