Two reasons:
- x86 can integrate rmap and rmap_pde and remove heuristics in
__gfn_to_rmap().
- Some architectures do not need rmap.
Since rmap is one of the most memory consuming stuff in KVM, ppc'd
better restrict the allocation to Book3S HV.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@xxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
---
arch/powerpc/include/asm/kvm_host.h | 1 +
arch/powerpc/kvm/book3s_64_mmu_hv.c | 6 ++--
arch/powerpc/kvm/book3s_hv_rm_mmu.c | 4 +-
arch/powerpc/kvm/powerpc.c | 8 +++++
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/mmu.c | 5 +--
arch/x86/kvm/x86.c | 55 ++++++++++++++++++++--------------
include/linux/kvm_host.h | 1 -
virt/kvm/kvm_main.c | 11 +------
9 files changed, 49 insertions(+), 44 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 572ad01..a29e091 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -221,6 +221,7 @@ struct revmap_entry {
#define KVMPPC_GOT_PAGE 0x80
struct kvm_arch_memory_slot {
+ unsigned long *rmap;
};
struct kvm_arch {
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 3c635c0..d95d113 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -705,7 +705,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
goto out_unlock;
hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID;
- rmap = &memslot->rmap[gfn - memslot->base_gfn];
+ rmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
lock_rmap(rmap);
/* Check if we might have been invalidated; let the guest retry if so */
@@ -788,7 +788,7 @@ static int kvm_handle_hva_range(struct kvm *kvm,
for (; gfn < gfn_end; ++gfn) {
gfn_t gfn_offset = gfn - memslot->base_gfn;
- ret = handler(kvm, &memslot->rmap[gfn_offset], gfn);
+ ret = handler(kvm, &memslot->arch.rmap[gfn_offset], gfn);
retval |= ret;
}
}
@@ -1036,7 +1036,7 @@ long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
unsigned long *rmapp, *map;
preempt_disable();
- rmapp = memslot->rmap;
+ rmapp = memslot->arch.rmap;
map = memslot->dirty_bitmap;
for (i = 0; i < memslot->npages; ++i) {
if (kvm_test_clear_dirty(kvm, rmapp))
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 5c70d19..56ac1a5 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -84,7 +84,7 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index,
if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
return;
- rmap = real_vmalloc_addr(&memslot->rmap[gfn - memslot->base_gfn]);
+ rmap = real_vmalloc_addr(&memslot->arch.rmap[gfn - memslot->base_gfn]);
lock_rmap(rmap);
head = *rmap & KVMPPC_RMAP_INDEX;
@@ -180,7 +180,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
if (!slot_is_aligned(memslot, psize))
return H_PARAMETER;
slot_fn = gfn - memslot->base_gfn;
- rmap = &memslot->rmap[slot_fn];
+ rmap = &memslot->arch.rmap[slot_fn];
if (!kvm->arch.using_mmu_notifiers) {
physp = kvm->arch.slot_phys[memslot->id];
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 87f4dc8..879b14a 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -302,10 +302,18 @@ long kvm_arch_dev_ioctl(struct file *filp,
void kvm_arch_free_memslot(struct kvm_memory_slot *free,
struct kvm_memory_slot *dont)
{
+ if (!dont || free->arch.rmap != dont->arch.rmap) {
+ vfree(free->arch.rmap);
+ free->arch.rmap = NULL;
+ }
}
int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
{
+ slot->arch.rmap = vzalloc(npages * sizeof(*slot->arch.rmap));
+ if (!slot->arch.rmap)
+ return -ENOMEM;
+
return 0;
}
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 48e7131..1309e69 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -504,7 +504,7 @@ struct kvm_lpage_info {
};
struct kvm_arch_memory_slot {
- unsigned long *rmap_pde[KVM_NR_PAGE_SIZES - 1];
+ unsigned long *rmap[KVM_NR_PAGE_SIZES];
struct kvm_lpage_info *lpage_info[KVM_NR_PAGE_SIZES - 1];
};
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index ee768bb..aa9a987 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -970,11 +970,8 @@ static unsigned long *__gfn_to_rmap(gfn_t gfn, int level,
{
unsigned long idx;
- if (likely(level == PT_PAGE_TABLE_LEVEL))
- return &slot->rmap[gfn - slot->base_gfn];
-
idx = gfn_to_index(gfn, slot->base_gfn, level);
- return &slot->arch.rmap_pde[level - PT_DIRECTORY_LEVEL][idx];
+ return &slot->arch.rmap[level - PT_PAGE_TABLE_LEVEL][idx];
}
/*
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 701dbd4..f9fc9b6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6299,14 +6299,18 @@ void kvm_arch_free_memslot(struct kvm_memory_slot *free,
{
int i;
- for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
- if (!dont || free->arch.rmap_pde[i] != dont->arch.rmap_pde[i]) {
- kvm_kvfree(free->arch.rmap_pde[i]);
- free->arch.rmap_pde[i] = NULL;
+ for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
+ if (!dont || free->arch.rmap[i] != dont->arch.rmap[i]) {
+ kvm_kvfree(free->arch.rmap[i]);
+ free->arch.rmap[i] = NULL;
}
- if (!dont || free->arch.lpage_info[i] != dont->arch.lpage_info[i]) {
- kvm_kvfree(free->arch.lpage_info[i]);
- free->arch.lpage_info[i] = NULL;
+ if (i == 0)
+ continue;
+
+ if (!dont || free->arch.lpage_info[i - 1] !=
+ dont->arch.lpage_info[i - 1]) {
+ kvm_kvfree(free->arch.lpage_info[i - 1]);
+ free->arch.lpage_info[i - 1] = NULL;
}
}
}
@@ -6315,28 +6319,30 @@ int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
{
int i;
- for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
+ for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
unsigned long ugfn;
int lpages;
- int level = i + 2;
+ int level = i + 1;
lpages = gfn_to_index(slot->base_gfn + npages - 1,
slot->base_gfn, level) + 1;
- slot->arch.rmap_pde[i] =
- kvm_kvzalloc(lpages * sizeof(*slot->arch.rmap_pde[i]));
- if (!slot->arch.rmap_pde[i])
+ slot->arch.rmap[i] =
+ kvm_kvzalloc(lpages * sizeof(*slot->arch.rmap[i]));
+ if (!slot->arch.rmap[i])
goto out_free;
+ if (i == 0)
+ continue;
- slot->arch.lpage_info[i] =
- kvm_kvzalloc(lpages * sizeof(*slot->arch.lpage_info[i]));
- if (!slot->arch.lpage_info[i])
+ slot->arch.lpage_info[i - 1] = kvm_kvzalloc(lpages *
+ sizeof(*slot->arch.lpage_info[i - 1]));
+ if (!slot->arch.lpage_info[i - 1])
goto out_free;
if (slot->base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
- slot->arch.lpage_info[i][0].write_count = 1;
+ slot->arch.lpage_info[i - 1][0].write_count = 1;
if ((slot->base_gfn + npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
- slot->arch.lpage_info[i][lpages - 1].write_count = 1;
+ slot->arch.lpage_info[i - 1][lpages - 1].write_count = 1;
ugfn = slot->userspace_addr >> PAGE_SHIFT;
/*
* If the gfn and userspace address are not aligned wrt each
@@ -6348,18 +6354,21 @@ int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
unsigned long j;
for (j = 0; j < lpages; ++j)
- slot->arch.lpage_info[i][j].write_count = 1;
+ slot->arch.lpage_info[i - 1][j].write_count = 1;
}
}
return 0;
out_free:
- for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
- kvm_kvfree(slot->arch.rmap_pde[i]);
- kvm_kvfree(slot->arch.lpage_info[i]);
- slot->arch.rmap_pde[i] = NULL;
- slot->arch.lpage_info[i] = NULL;
+ for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
+ kvm_kvfree(slot->arch.rmap[i]);
+ slot->arch.rmap[i] = NULL;
+ if (i == 0)
+ continue;
+
+ kvm_kvfree(slot->arch.lpage_info[i - 1]);
+ slot->arch.lpage_info[i - 1] = NULL;
}
return -ENOMEM;
}
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index dbc65f9..3c16f0f 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -213,7 +213,6 @@ struct kvm_memory_slot {
gfn_t base_gfn;
unsigned long npages;
unsigned long flags;
- unsigned long *rmap;
unsigned long *dirty_bitmap;
struct kvm_arch_memory_slot arch;
unsigned long userspace_addr;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index bcf973e..14ec567 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -550,16 +550,12 @@ static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
struct kvm_memory_slot *dont)
{
- if (!dont || free->rmap != dont->rmap)
- vfree(free->rmap);
-
if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
kvm_destroy_dirty_bitmap(free);
kvm_arch_free_memslot(free, dont);
free->npages = 0;
- free->rmap = NULL;
}
void kvm_free_physmem(struct kvm *kvm)
@@ -768,11 +764,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
if (npages && !old.npages) {
new.user_alloc = user_alloc;
new.userspace_addr = mem->userspace_addr;
-#ifndef CONFIG_S390
- new.rmap = vzalloc(npages * sizeof(*new.rmap));
- if (!new.rmap)
- goto out_free;
-#endif /* not defined CONFIG_S390 */
+
if (kvm_arch_create_memslot(&new, npages))
goto out_free;
}
@@ -831,7 +823,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
/* actual memory is freed via old in kvm_free_physmem_slot below */
if (!npages) {
- new.rmap = NULL;
new.dirty_bitmap = NULL;
memset(&new.arch, 0, sizeof(new.arch));
}
--
1.7.5.4
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