KVM: PPC: Improve split mode

When in split mode, instruction relocation and data relocation are not equal.

So far we implemented this mode by reserving a special pseudo-VSID for the
two cases and flushing all PTEs when going into split mode, which is slow.

Unfortunately 32bit Linux and Mac OS X use split mode extensively. So to not
slow down things too much, I came up with a different idea: Mark the split
mode with a bit in the VSID and then treat it like any other segment.

This means we can just flush the shadow segment cache, but keep the PTEs
intact. I verified that this works with ppc32 Linux and Mac OS X 10.4
guests and does speed them up.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Alexander Graf 2010-04-20 02:49:48 +02:00 committed by Avi Kivity
parent 7fdaec997c
commit f7bc74e1c3
4 changed files with 52 additions and 45 deletions

View File

@ -100,11 +100,10 @@ struct kvmppc_vcpu_book3s {
#define CONTEXT_GUEST 1
#define CONTEXT_GUEST_END 2
#define VSID_REAL_DR 0x7ffffffffff00000ULL
#define VSID_REAL_IR 0x7fffffffffe00000ULL
#define VSID_SPLIT_MASK 0x7fffffffffe00000ULL
#define VSID_REAL 0x7fffffffffc00000ULL
#define VSID_BAT 0x7fffffffffb00000ULL
#define VSID_REAL 0x1fffffffffc00000ULL
#define VSID_BAT 0x1fffffffffb00000ULL
#define VSID_REAL_DR 0x2000000000000000ULL
#define VSID_REAL_IR 0x4000000000000000ULL
#define VSID_PR 0x8000000000000000ULL
extern void kvmppc_mmu_pte_flush(struct kvm_vcpu *vcpu, ulong ea, ulong ea_mask);

View File

@ -148,16 +148,8 @@ void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 msr)
}
}
if (((vcpu->arch.msr & (MSR_IR|MSR_DR)) != (old_msr & (MSR_IR|MSR_DR))) ||
(vcpu->arch.msr & MSR_PR) != (old_msr & MSR_PR)) {
bool dr = (vcpu->arch.msr & MSR_DR) ? true : false;
bool ir = (vcpu->arch.msr & MSR_IR) ? true : false;
/* Flush split mode PTEs */
if (dr != ir)
kvmppc_mmu_pte_vflush(vcpu, VSID_SPLIT_MASK,
VSID_SPLIT_MASK);
if ((vcpu->arch.msr & (MSR_PR|MSR_IR|MSR_DR)) !=
(old_msr & (MSR_PR|MSR_IR|MSR_DR))) {
kvmppc_mmu_flush_segments(vcpu);
kvmppc_mmu_map_segment(vcpu, kvmppc_get_pc(vcpu));
}
@ -535,6 +527,7 @@ int kvmppc_handle_pagefault(struct kvm_run *run, struct kvm_vcpu *vcpu,
bool is_mmio = false;
bool dr = (vcpu->arch.msr & MSR_DR) ? true : false;
bool ir = (vcpu->arch.msr & MSR_IR) ? true : false;
u64 vsid;
relocated = data ? dr : ir;
@ -552,13 +545,20 @@ int kvmppc_handle_pagefault(struct kvm_run *run, struct kvm_vcpu *vcpu,
switch (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
case 0:
pte.vpage |= VSID_REAL;
pte.vpage |= ((u64)VSID_REAL << (SID_SHIFT - 12));
break;
case MSR_DR:
pte.vpage |= VSID_REAL_DR;
break;
case MSR_IR:
pte.vpage |= VSID_REAL_IR;
vcpu->arch.mmu.esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
if ((vcpu->arch.msr & (MSR_DR|MSR_IR)) == MSR_DR)
pte.vpage |= ((u64)VSID_REAL_DR << (SID_SHIFT - 12));
else
pte.vpage |= ((u64)VSID_REAL_IR << (SID_SHIFT - 12));
pte.vpage |= vsid;
if (vsid == -1)
page_found = -EINVAL;
break;
}

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@ -330,30 +330,35 @@ static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool lar
static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
u64 *vsid)
{
ulong ea = esid << SID_SHIFT;
struct kvmppc_sr *sr;
u64 gvsid = esid;
if (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
sr = find_sr(to_book3s(vcpu), ea);
if (sr->valid)
gvsid = sr->vsid;
}
/* In case we only have one of MSR_IR or MSR_DR set, let's put
that in the real-mode context (and hope RM doesn't access
high memory) */
switch (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
case 0:
*vsid = (VSID_REAL >> 16) | esid;
*vsid = VSID_REAL | esid;
break;
case MSR_IR:
*vsid = (VSID_REAL_IR >> 16) | esid;
*vsid = VSID_REAL_IR | gvsid;
break;
case MSR_DR:
*vsid = (VSID_REAL_DR >> 16) | esid;
*vsid = VSID_REAL_DR | gvsid;
break;
case MSR_DR|MSR_IR:
{
ulong ea = esid << SID_SHIFT;
struct kvmppc_sr *sr = find_sr(to_book3s(vcpu), ea);
if (!sr->valid)
return -1;
*vsid = sr->vsid;
break;
}
default:
BUG();
}

View File

@ -442,29 +442,32 @@ static void kvmppc_mmu_book3s_64_tlbie(struct kvm_vcpu *vcpu, ulong va,
static int kvmppc_mmu_book3s_64_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
u64 *vsid)
{
switch (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
case 0:
*vsid = (VSID_REAL >> 16) | esid;
break;
case MSR_IR:
*vsid = (VSID_REAL_IR >> 16) | esid;
break;
case MSR_DR:
*vsid = (VSID_REAL_DR >> 16) | esid;
break;
case MSR_DR|MSR_IR:
{
ulong ea;
struct kvmppc_slb *slb;
ea = esid << SID_SHIFT;
ulong ea = esid << SID_SHIFT;
struct kvmppc_slb *slb;
u64 gvsid = esid;
if (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
slb = kvmppc_mmu_book3s_64_find_slbe(to_book3s(vcpu), ea);
if (slb)
*vsid = slb->vsid;
else
gvsid = slb->vsid;
}
switch (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
case 0:
*vsid = VSID_REAL | esid;
break;
case MSR_IR:
*vsid = VSID_REAL_IR | gvsid;
break;
case MSR_DR:
*vsid = VSID_REAL_DR | gvsid;
break;
case MSR_DR|MSR_IR:
if (!slb)
return -ENOENT;
*vsid = gvsid;
break;
}
default:
BUG();
break;