From: Avi Kivity <avi@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: kvm@vger.kernel.org, Hollis Blanchard <hollisb@us.ibm.com>
Subject: [PATCH 29/40] KVM: powerpc: Map guest userspace with TID=0 mappings
Date: Tue, 23 Sep 2008 16:46:43 +0300 [thread overview]
Message-ID: <1222177614-26669-30-git-send-email-avi@redhat.com> (raw)
In-Reply-To: <1222177614-26669-1-git-send-email-avi@redhat.com>
From: Hollis Blanchard <hollisb@us.ibm.com>
When we use TID=N userspace mappings, we must ensure that kernel mappings have
been destroyed when entering userspace. Using TID=1/TID=0 for kernel/user
mappings and running userspace with PID=0 means that userspace can't access the
kernel mappings, but the kernel can directly access userspace.
The net is that we don't need to flush the TLB on privilege switches, but we do
on guest context switches (which are far more infrequent). Guest boot time
performance improvement: about 30%.
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
---
arch/powerpc/include/asm/kvm_host.h | 4 +++
arch/powerpc/include/asm/kvm_ppc.h | 9 ++++++++
arch/powerpc/kernel/asm-offsets.c | 2 +-
arch/powerpc/kvm/44x_tlb.c | 39 ++++++++++++++++++++--------------
arch/powerpc/kvm/booke_guest.c | 2 +
arch/powerpc/kvm/booke_interrupts.S | 2 +-
arch/powerpc/kvm/emulate.c | 2 +-
7 files changed, 41 insertions(+), 19 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 4338b03..34b52b7 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -129,7 +129,11 @@ struct kvm_vcpu_arch {
u32 ivor[16];
u32 ivpr;
u32 pir;
+
+ u32 shadow_pid;
u32 pid;
+ u32 swap_pid;
+
u32 pvr;
u32 ccr0;
u32 ccr1;
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 8e7e429..8931ba7 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -64,6 +64,7 @@ extern void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn,
extern void kvmppc_mmu_invalidate(struct kvm_vcpu *vcpu, gva_t eaddr,
gva_t eend, u32 asid);
extern void kvmppc_mmu_priv_switch(struct kvm_vcpu *vcpu, int usermode);
+extern void kvmppc_mmu_switch_pid(struct kvm_vcpu *vcpu, u32 pid);
/* XXX Book E specific */
extern void kvmppc_tlbe_set_modified(struct kvm_vcpu *vcpu, unsigned int i);
@@ -95,4 +96,12 @@ static inline void kvmppc_set_msr(struct kvm_vcpu *vcpu, u32 new_msr)
kvm_vcpu_block(vcpu);
}
+static inline void kvmppc_set_pid(struct kvm_vcpu *vcpu, u32 new_pid)
+{
+ if (vcpu->arch.pid != new_pid) {
+ vcpu->arch.pid = new_pid;
+ vcpu->arch.swap_pid = 1;
+ }
+}
+
#endif /* __POWERPC_KVM_PPC_H__ */
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 1631d67..52649da 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -369,7 +369,7 @@ int main(void)
DEFINE(VCPU_SPRG5, offsetof(struct kvm_vcpu, arch.sprg5));
DEFINE(VCPU_SPRG6, offsetof(struct kvm_vcpu, arch.sprg6));
DEFINE(VCPU_SPRG7, offsetof(struct kvm_vcpu, arch.sprg7));
- DEFINE(VCPU_PID, offsetof(struct kvm_vcpu, arch.pid));
+ DEFINE(VCPU_SHADOW_PID, offsetof(struct kvm_vcpu, arch.shadow_pid));
DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst));
DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear));
diff --git a/arch/powerpc/kvm/44x_tlb.c b/arch/powerpc/kvm/44x_tlb.c
index 06a5fcf..3594bbd 100644
--- a/arch/powerpc/kvm/44x_tlb.c
+++ b/arch/powerpc/kvm/44x_tlb.c
@@ -170,7 +170,7 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid,
/* XXX what about AS? */
- stlbe->tid = asid & 0xff;
+ stlbe->tid = !(asid & 0xff);
/* Force TS=1 for all guest mappings. */
/* For now we hardcode 4KB mappings, but it will be important to
@@ -190,7 +190,7 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid,
void kvmppc_mmu_invalidate(struct kvm_vcpu *vcpu, gva_t eaddr,
gva_t eend, u32 asid)
{
- unsigned int pid = asid & 0xff;
+ unsigned int pid = !(asid & 0xff);
int i;
/* XXX Replace loop with fancy data structures. */
@@ -222,23 +222,30 @@ void kvmppc_mmu_invalidate(struct kvm_vcpu *vcpu, gva_t eaddr,
up_write(¤t->mm->mmap_sem);
}
-/* Invalidate all mappings, so that when they fault back in they will get the
- * proper permission bits. */
+/* Invalidate all mappings on the privilege switch after PID has been changed.
+ * The guest always runs with PID=1, so we must clear the entire TLB when
+ * switching address spaces. */
void kvmppc_mmu_priv_switch(struct kvm_vcpu *vcpu, int usermode)
{
int i;
- /* XXX Replace loop with fancy data structures. */
- down_write(¤t->mm->mmap_sem);
- for (i = 0; i <= tlb_44x_hwater; i++) {
- struct tlbe *stlbe = &vcpu->arch.shadow_tlb[i];
-
- kvmppc_44x_shadow_release(vcpu, i);
- stlbe->word0 = 0;
- kvmppc_tlbe_set_modified(vcpu, i);
- KVMTRACE_5D(STLB_INVAL, vcpu, i,
- stlbe->tid, stlbe->word0, stlbe->word1,
- stlbe->word2, handler);
+ if (vcpu->arch.swap_pid) {
+ /* XXX Replace loop with fancy data structures. */
+ down_write(¤t->mm->mmap_sem);
+ for (i = 0; i <= tlb_44x_hwater; i++) {
+ struct tlbe *stlbe = &vcpu->arch.shadow_tlb[i];
+
+ /* Future optimization: clear only userspace mappings. */
+ kvmppc_44x_shadow_release(vcpu, i);
+ stlbe->word0 = 0;
+ kvmppc_tlbe_set_modified(vcpu, i);
+ KVMTRACE_5D(STLB_INVAL, vcpu, i,
+ stlbe->tid, stlbe->word0, stlbe->word1,
+ stlbe->word2, handler);
+ }
+ up_write(¤t->mm->mmap_sem);
+ vcpu->arch.swap_pid = 0;
}
- up_write(¤t->mm->mmap_sem);
+
+ vcpu->arch.shadow_pid = !usermode;
}
diff --git a/arch/powerpc/kvm/booke_guest.c b/arch/powerpc/kvm/booke_guest.c
index 3cca079..7b2591e 100644
--- a/arch/powerpc/kvm/booke_guest.c
+++ b/arch/powerpc/kvm/booke_guest.c
@@ -486,6 +486,8 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
vcpu->arch.msr = 0;
vcpu->arch.gpr[1] = (16<<20) - 8; /* -8 for the callee-save LR slot */
+ vcpu->arch.shadow_pid = 1;
+
/* Eye-catching number so we know if the guest takes an interrupt
* before it's programmed its own IVPR. */
vcpu->arch.ivpr = 0x55550000;
diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S
index 564ea32..95e165b 100644
--- a/arch/powerpc/kvm/booke_interrupts.S
+++ b/arch/powerpc/kvm/booke_interrupts.S
@@ -332,7 +332,7 @@ lightweight_exit:
mfspr r3, SPRN_PID
stw r3, VCPU_HOST_PID(r4)
- lwz r3, VCPU_PID(r4)
+ lwz r3, VCPU_SHADOW_PID(r4)
mtspr SPRN_PID, r3
/* Prevent all asynchronous TLB updates. */
diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
index c3ed63b..0fce4fb 100644
--- a/arch/powerpc/kvm/emulate.c
+++ b/arch/powerpc/kvm/emulate.c
@@ -508,7 +508,7 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
case SPRN_MMUCR:
vcpu->arch.mmucr = vcpu->arch.gpr[rs]; break;
case SPRN_PID:
- vcpu->arch.pid = vcpu->arch.gpr[rs]; break;
+ kvmppc_set_pid(vcpu, vcpu->arch.gpr[rs]); break;
case SPRN_CCR0:
vcpu->arch.ccr0 = vcpu->arch.gpr[rs]; break;
case SPRN_CCR1:
--
1.6.0.1
next prev parent reply other threads:[~2008-09-23 13:53 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-09-23 13:46 [PATCH 00/40] KVM Updates for 2.6.28 merge window (part 1 of 3) Avi Kivity
2008-09-23 13:46 ` [PATCH 01/40] KVM: VMX: Rename misnamed msr bits Avi Kivity
2008-09-23 13:46 ` [PATCH 02/40] KVM: x86: accessors for guest registers Avi Kivity
2008-09-23 13:46 ` [PATCH 03/40] KVM: Move KVM TRACE DEFINITIONS to common header Avi Kivity
2008-09-23 13:46 ` [PATCH 04/40] KVM: Introduce kvm_set_irq to inject interrupts in guests Avi Kivity
2008-09-23 13:46 ` [PATCH 05/40] KVM: MMU: Separate the code for unlinking a shadow page from its parents Avi Kivity
2008-09-23 13:46 ` [PATCH 06/40] KVM: MMU: Simplify kvm_mmu_zap_page() Avi Kivity
2008-09-23 13:46 ` [PATCH 07/40] KVM: Move NMI IRET fault processing to new vmx_complete_interrupts() Avi Kivity
2008-09-23 13:46 ` [PATCH 08/40] KVM: VMX: Move nmi injection failure processing to vm exit path Avi Kivity
2008-09-23 13:46 ` [PATCH 09/40] KVM: Clear exception queue before emulating an instruction Avi Kivity
2008-09-23 13:46 ` [PATCH 10/40] KVM: VMX: Fix pending exception processing Avi Kivity
2008-09-23 13:46 ` [PATCH 11/40] KVM: Add a pending interrupt queue Avi Kivity
2008-09-23 13:46 ` [PATCH 12/40] KVM: VMX: Move interrupt post-processing to vmx_complete_interrupts() Avi Kivity
2008-09-23 13:46 ` [PATCH 13/40] KVM: VMX: Remove redundant check in handle_rmode_exception Avi Kivity
2008-09-23 13:46 ` [PATCH 14/40] KVM: Consolidate PIC isr clearing into a function Avi Kivity
2008-09-23 13:46 ` [PATCH 15/40] KVM: Consolidate XX_VECTOR defines Avi Kivity
2008-09-23 13:46 ` [PATCH 16/40] KVM: VMX: Reinject real mode exception Avi Kivity
2008-09-23 13:46 ` [PATCH 17/40] KVM: VMX: Unify register save/restore across 32 and 64 bit hosts Avi Kivity
2008-09-23 13:46 ` [PATCH 18/40] KVM: SVM: " Avi Kivity
2008-09-23 13:46 ` [PATCH 19/40] KVM: kvmtrace: Remove use of bit fields in kvm trace structure Avi Kivity
2008-09-23 13:46 ` [PATCH 20/40] KVM: kvmtrace: replace get_cycles with ktime_get v3 Avi Kivity
2008-09-23 13:46 ` [PATCH 21/40] KVM: ppc: enable KVM_TRACE building for powerpc Avi Kivity
2008-09-23 13:46 ` [PATCH 22/40] KVM: ppc: adds trace points for ppc tlb activity Avi Kivity
2008-09-23 13:46 ` [PATCH 23/40] KVM: ppc: trace powerpc instruction emulation Avi Kivity
2008-09-23 13:46 ` [PATCH 24/40] KVM: VMX: Avoid vmwrite(HOST_RSP) when possible Avi Kivity
2008-09-23 13:46 ` [PATCH 25/40] KVM: Ignore DEBUGCTL MSRs with no effect Avi Kivity
2008-09-23 13:46 ` [PATCH 26/40] KVM: ppc: guest breakpoint support Avi Kivity
2008-09-23 13:46 ` [PATCH 27/40] KVM: ppc: Stop saving host TLB state Avi Kivity
2008-09-23 13:46 ` [PATCH 28/40] KVM: ppc: Write only modified shadow entries into the TLB on exit Avi Kivity
2008-09-23 13:46 ` Avi Kivity [this message]
2008-09-23 13:46 ` [PATCH 30/40] KVM: Add irq ack notifier list Avi Kivity
2008-09-23 13:46 ` [PATCH 31/40] KVM: irq ack notification Avi Kivity
2008-09-23 13:46 ` [PATCH 32/40] KVM: PIT: fix injection logic and count Avi Kivity
2008-09-23 13:46 ` [PATCH 33/40] x86: paravirt: factor out cpu_khz to common code Avi Kivity
2008-09-23 13:46 ` [PATCH 34/40] x86: KVM guest: use paravirt function to calculate cpu khz Avi Kivity
2008-09-23 13:46 ` [PATCH 35/40] KVM: direct mmio pfn check Avi Kivity
2008-09-23 13:46 ` [PATCH 36/40] KVM: pci device assignment Avi Kivity
2008-09-23 13:46 ` [PATCH 37/40] KVM: Reduce kvm stack usage in kvm_arch_vm_ioctl() Avi Kivity
2008-09-23 13:46 ` [PATCH 38/40] KVM: Reduce stack usage in kvm_vcpu_ioctl() Avi Kivity
2008-09-23 13:46 ` [PATCH 39/40] KVM: Reduce stack usage in kvm_arch_vcpu_ioctl() Avi Kivity
2008-09-23 13:46 ` [PATCH 40/40] KVM: Reduce stack usage in kvm_pv_mmu_op() Avi Kivity
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