[PATCH 11/56] KVM: PPC: e500: Track TLB1 entries with a bitmap

Alexander Graf
2012-03-15T12:10:40Z

From: Scott Wood <scottwood@freescale.com>

Rather than invalidate everything when a TLB1 entry needs to be
taken down, keep track of which host TLB1 entries are used for
a given guest TLB1 entry, and invalidate just those entries.

Based on code from Ashish Kalra <Ashish.Kalra@freescale.com>
and Liu Yu <yu.liu@freescale.com>.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
arch/powerpc/kvm/e500.h | 5 +++
arch/powerpc/kvm/e500_tlb.c | 72 ++++++++++++++++++++++++++++++++++++++++---
2 files changed, 72 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kvm/e500.h b/arch/powerpc/kvm/e500.h
index 34cef08..f4dee55 100644
--- a/arch/powerpc/kvm/e500.h
+++ b/arch/powerpc/kvm/e500.h
@@ -2,6 +2,7 @@
* Copyright (C) 2008-2011 Freescale Semiconductor, Inc. All rights reserved.
*
* Author: Yu Liu <yu.liu@freescale.com>
+ * Ashish Kalra <ashish.kalra@freescale.com>
*
* Description:
* This file is based on arch/powerpc/kvm/44x_tlb.h and
@@ -25,6 +26,7 @@

#define E500_TLB_VALID 1
#define E500_TLB_DIRTY 2
+#define E500_TLB_BITMAP 4

struct tlbe_ref {
pfn_t pfn;
@@ -82,6 +84,9 @@ struct kvmppc_vcpu_e500 {
struct page **shared_tlb_pages;
int num_shared_tlb_pages;

+ u64 *g2h_tlb1_map;
+ unsigned int *h2g_tlb1_rmap;
+
#ifdef CONFIG_KVM_E500
u32 pid[E500_PID_NUM];

diff --git a/arch/powerpc/kvm/e500_tlb.c b/arch/powerpc/kvm/e500_tlb.c
index 9925fc6..c8ce51d 100644
--- a/arch/powerpc/kvm/e500_tlb.c
+++ b/arch/powerpc/kvm/e500_tlb.c
@@ -2,6 +2,7 @@
* Copyright (C) 2008-2011 Freescale Semiconductor, Inc. All rights reserved.
*
* Author: Yu Liu, yu.liu@freescale.com
+ * Ashish Kalra, ashish.kalra@freescale.com
*
* Description:
* This file is based on arch/powerpc/kvm/44x_tlb.c,
@@ -175,8 +176,28 @@ static void inval_gtlbe_on_host(struct kvmppc_vcpu_e500 *vcpu_e500,
struct kvm_book3e_206_tlb_entry *gtlbe get_entry(vcpu_e500, tlbsel, esel);

- if (tlbsel = 1) {
- kvmppc_e500_tlbil_all(vcpu_e500);
+ if (tlbsel = 1 &&
+ vcpu_e500->gtlb_priv[1][esel].ref.flags & E500_TLB_BITMAP) {
+ u64 tmp = vcpu_e500->g2h_tlb1_map[esel];
+ int hw_tlb_indx;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ while (tmp) {
+ hw_tlb_indx = __ilog2_u64(tmp & -tmp);
+ mtspr(SPRN_MAS0,
+ MAS0_TLBSEL(1) |
+ MAS0_ESEL(to_htlb1_esel(hw_tlb_indx)));
+ mtspr(SPRN_MAS1, 0);
+ asm volatile("tlbwe");
+ vcpu_e500->h2g_tlb1_rmap[hw_tlb_indx] = 0;
+ tmp &= tmp - 1;
+ }
+ mb();
+ vcpu_e500->g2h_tlb1_map[esel] = 0;
+ vcpu_e500->gtlb_priv[1][esel].ref.flags &= ~E500_TLB_BITMAP;
+ local_irq_restore(flags);
+
return;
}

@@ -282,6 +303,16 @@ static inline void kvmppc_e500_ref_release(struct tlbe_ref *ref)
}
}

+static void clear_tlb1_bitmap(struct kvmppc_vcpu_e500 *vcpu_e500)
+{
+ if (vcpu_e500->g2h_tlb1_map)
+ memset(vcpu_e500->g2h_tlb1_map,
+ sizeof(u64) * vcpu_e500->gtlb_params[1].entries, 0);
+ if (vcpu_e500->h2g_tlb1_rmap)
+ memset(vcpu_e500->h2g_tlb1_rmap,
+ sizeof(unsigned int) * host_tlb_params[1].entries, 0);
+}
+
static void clear_tlb_privs(struct kvmppc_vcpu_e500 *vcpu_e500)
{
int tlbsel = 0;
@@ -511,7 +542,7 @@ static void kvmppc_e500_tlb0_map(struct kvmppc_vcpu_e500 *vcpu_e500,
/* XXX for both one-one and one-to-many , for now use TLB1 */
static int kvmppc_e500_tlb1_map(struct kvmppc_vcpu_e500 *vcpu_e500,
u64 gvaddr, gfn_t gfn, struct kvm_book3e_206_tlb_entry *gtlbe,
- struct kvm_book3e_206_tlb_entry *stlbe)
+ struct kvm_book3e_206_tlb_entry *stlbe, int esel)
{
struct tlbe_ref *ref;
unsigned int victim;
@@ -524,6 +555,14 @@ static int kvmppc_e500_tlb1_map(struct kvmppc_vcpu_e500 *vcpu_e500,
ref = &vcpu_e500->tlb_refs[1][victim];
kvmppc_e500_shadow_map(vcpu_e500, gvaddr, gfn, gtlbe, 1, stlbe, ref);

+ vcpu_e500->g2h_tlb1_map[esel] |= (u64)1 << victim;
+ vcpu_e500->gtlb_priv[1][esel].ref.flags |= E500_TLB_BITMAP;
+ if (vcpu_e500->h2g_tlb1_rmap[victim]) {
+ unsigned int idx = vcpu_e500->h2g_tlb1_rmap[victim];
+ vcpu_e500->g2h_tlb1_map[idx] &= ~(1ULL << victim);
+ }
+ vcpu_e500->h2g_tlb1_rmap[victim] = esel;
+
return victim;
}

@@ -728,7 +767,7 @@ int kvmppc_e500_emul_tlbwe(struct kvm_vcpu *vcpu)
* are mapped on the fly. */
stlbsel = 1;
sesel = kvmppc_e500_tlb1_map(vcpu_e500, eaddr,
- raddr >> PAGE_SHIFT, gtlbe, &stlbe);
+ raddr >> PAGE_SHIFT, gtlbe, &stlbe, esel);
break;

default:
@@ -856,7 +895,7 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 eaddr, gpa_t gpaddr,

stlbsel = 1;
sesel = kvmppc_e500_tlb1_map(vcpu_e500, eaddr, gfn,
- gtlbe, &stlbe);
+ gtlbe, &stlbe, esel);
break;
}

@@ -872,6 +911,9 @@ static void free_gtlb(struct kvmppc_vcpu_e500 *vcpu_e500)
{
int i;

+ clear_tlb1_bitmap(vcpu_e500);
+ kfree(vcpu_e500->g2h_tlb1_map);
+
clear_tlb_refs(vcpu_e500);
kfree(vcpu_e500->gtlb_priv[0]);
kfree(vcpu_e500->gtlb_priv[1]);
@@ -932,6 +974,7 @@ int kvm_vcpu_ioctl_config_tlb(struct kvm_vcpu *vcpu,
char *virt;
struct page **pages;
struct tlbe_priv *privs[2] = {};
+ u64 *g2h_bitmap = NULL;
size_t array_len;
u32 sets;
int num_pages, ret, i;
@@ -993,10 +1036,16 @@ int kvm_vcpu_ioctl_config_tlb(struct kvm_vcpu *vcpu,
if (!privs[0] || !privs[1])
goto err_put_page;

+ g2h_bitmap = kzalloc(sizeof(u64) * params.tlb_sizes[1],
+ GFP_KERNEL);
+ if (!g2h_bitmap)
+ goto err_put_page;
+
free_gtlb(vcpu_e500);

vcpu_e500->gtlb_priv[0] = privs[0];
vcpu_e500->gtlb_priv[1] = privs[1];
+ vcpu_e500->g2h_tlb1_map = g2h_bitmap;

vcpu_e500->gtlb_arch = (struct kvm_book3e_206_tlb_entry *)
(virt + (cfg->array & (PAGE_SIZE - 1)));
@@ -1129,6 +1178,18 @@ int kvmppc_e500_tlb_init(struct kvmppc_vcpu_e500 *vcpu_e500)
if (!vcpu_e500->gtlb_priv[1])
goto err;

+ vcpu_e500->g2h_tlb1_map = kzalloc(sizeof(unsigned int) *
+ vcpu_e500->gtlb_params[1].entries,
+ GFP_KERNEL);
+ if (!vcpu_e500->g2h_tlb1_map)
+ goto err;
+
+ vcpu_e500->h2g_tlb1_rmap = kzalloc(sizeof(unsigned int) *
+ host_tlb_params[1].entries,
+ GFP_KERNEL);
+ if (!vcpu_e500->h2g_tlb1_rmap)
+ goto err;
+
/* Init TLB configuration register */
vcpu->arch.tlbcfg[0] = mfspr(SPRN_TLB0CFG) &
~(TLBnCFG_N_ENTRY | TLBnCFG_ASSOC);
@@ -1154,6 +1215,7 @@ err:
void kvmppc_e500_tlb_uninit(struct kvmppc_vcpu_e500 *vcpu_e500)
{
free_gtlb(vcpu_e500);
+ kfree(vcpu_e500->h2g_tlb1_rmap);
kfree(vcpu_e500->tlb_refs[0]);
kfree(vcpu_e500->tlb_refs[1]);
}
--
1.6.0.2