[PATCH v2 2/7] KVM: MMU: introduce some macros to cleanup hlist traverseing

Xiao Guangrong
2010-06-04T13:56:44Z

Introduce for_each_gfn_sp() and for_each_gfn_indirect_valid_sp() to
cleanup hlist traverseing

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
arch/x86/kvm/mmu.c | 122 ++++++++++++++++++++--------------------------------
1 files changed, 47 insertions(+), 75 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index e962f26..75bd6df 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1201,6 +1201,17 @@ static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp)

static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp);

+#define for_each_gfn_sp(kvm, sp, gfn, pos, n) \
+ hlist_for_each_entry_safe(sp, pos, n, \
+ &(kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)], hash_link) \
+ if ((sp)->gfn != (gfn)) {} else
+
+#define for_each_gfn_indirect_valid_sp(kvm, sp, gfn, pos, n) \
+ hlist_for_each_entry_safe(sp, pos, n, \
+ &(kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)], hash_link) \
+ if ((sp)->gfn != (gfn) || (sp)->role.direct || \
+ (sp)->role.invalid) {} else
+
static int __kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
bool clear_unsync)
{
@@ -1244,16 +1255,12 @@ static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
/* @gfn should be write-protected at the call site */
static void kvm_sync_pages(struct kvm_vcpu *vcpu, gfn_t gfn)
{
- struct hlist_head *bucket;
struct kvm_mmu_page *s;
struct hlist_node *node, *n;
- unsigned index;
bool flush = false;

- index = kvm_page_table_hashfn(gfn);
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry_safe(s, node, n, bucket, hash_link) {
- if (s->gfn != gfn || !s->unsync || s->role.invalid)
+ for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node, n) {
+ if (!s->unsync)
continue;

WARN_ON(s->role.level != PT_PAGE_TABLE_LEVEL);
@@ -1365,9 +1372,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
u64 *parent_pte)
{
union kvm_mmu_page_role role;
- unsigned index;
unsigned quadrant;
- struct hlist_head *bucket;
struct kvm_mmu_page *sp;
struct hlist_node *node, *tmp;
bool need_sync = false;
@@ -1383,36 +1388,34 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1;
role.quadrant = quadrant;
}
- index = kvm_page_table_hashfn(gfn);
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry_safe(sp, node, tmp, bucket, hash_link)
- if (sp->gfn == gfn) {
- if (!need_sync && sp->unsync)
- need_sync = true;
+ for_each_gfn_sp(vcpu->kvm, sp, gfn, node, tmp) {
+ if (!need_sync && sp->unsync)
+ need_sync = true;

- if (sp->role.word != role.word)
- continue;
+ if (sp->role.word != role.word)
+ continue;

- if (sp->unsync && kvm_sync_page_transient(vcpu, sp))
- break;
+ if (sp->unsync && kvm_sync_page_transient(vcpu, sp))
+ break;

- mmu_page_add_parent_pte(vcpu, sp, parent_pte);
- if (sp->unsync_children) {
- set_bit(KVM_REQ_MMU_SYNC, &vcpu->requests);
- kvm_mmu_mark_parents_unsync(sp);
- } else if (sp->unsync)
- kvm_mmu_mark_parents_unsync(sp);
+ mmu_page_add_parent_pte(vcpu, sp, parent_pte);
+ if (sp->unsync_children) {
+ set_bit(KVM_REQ_MMU_SYNC, &vcpu->requests);
+ kvm_mmu_mark_parents_unsync(sp);
+ } else if (sp->unsync)
+ kvm_mmu_mark_parents_unsync(sp);

- trace_kvm_mmu_get_page(sp, false);
- return sp;
- }
+ trace_kvm_mmu_get_page(sp, false);
+ return sp;
+ }
++vcpu->kvm->stat.mmu_cache_miss;
sp = kvm_mmu_alloc_page(vcpu, parent_pte, direct);
if (!sp)
return sp;
sp->gfn = gfn;
sp->role = role;
- hlist_add_head(&sp->hash_link, bucket);
+ hlist_add_head(&sp->hash_link,
+ &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]);
if (!direct) {
if (rmap_write_protect(vcpu->kvm, gfn))
kvm_flush_remote_tlbs(vcpu->kvm);
@@ -1617,46 +1620,34 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages)

static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn)
{
- unsigned index;
- struct hlist_head *bucket;
struct kvm_mmu_page *sp;
struct hlist_node *node, *n;
int r;

pgprintk("%s: looking for gfn %lx\n", __func__, gfn);
r = 0;
- index = kvm_page_table_hashfn(gfn);
- bucket = &kvm->arch.mmu_page_hash[index];
restart:
- hlist_for_each_entry_safe(sp, node, n, bucket, hash_link)
- if (sp->gfn == gfn && !sp->role.direct && !sp->role.invalid) {
- pgprintk("%s: gfn %lx role %x\n", __func__, gfn,
- sp->role.word);
- r = 1;
- if (kvm_mmu_zap_page(kvm, sp))
- goto restart;
- }
+ for_each_gfn_indirect_valid_sp(kvm, sp, gfn, node, n) {
+ pgprintk("%s: gfn %lx role %x\n", __func__, gfn,
+ sp->role.word);
+ r = 1;
+ if (kvm_mmu_zap_page(kvm, sp))
+ goto restart;
+ }
return r;
}

static void mmu_unshadow(struct kvm *kvm, gfn_t gfn)
{
- unsigned index;
- struct hlist_head *bucket;
struct kvm_mmu_page *sp;
struct hlist_node *node, *nn;

- index = kvm_page_table_hashfn(gfn);
- bucket = &kvm->arch.mmu_page_hash[index];
restart:
- hlist_for_each_entry_safe(sp, node, nn, bucket, hash_link) {
- if (sp->gfn == gfn && !sp->role.direct
- && !sp->role.invalid) {
- pgprintk("%s: zap %lx %x\n",
- __func__, gfn, sp->role.word);
- if (kvm_mmu_zap_page(kvm, sp))
- goto restart;
- }
+ for_each_gfn_indirect_valid_sp(kvm, sp, gfn, node, nn) {
+ pgprintk("%s: zap %lx %x\n",
+ __func__, gfn, sp->role.word);
+ if (kvm_mmu_zap_page(kvm, sp))
+ goto restart;
}
}

@@ -1799,17 +1790,11 @@ static void __kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)

static void kvm_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn)
{
- struct hlist_head *bucket;
struct kvm_mmu_page *s;
struct hlist_node *node, *n;
- unsigned index;
-
- index = kvm_page_table_hashfn(gfn);
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];

- hlist_for_each_entry_safe(s, node, n, bucket, hash_link) {
- if (s->gfn != gfn || s->role.direct || s->unsync ||
- s->role.invalid)
+ for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node, n) {
+ if (s->unsync)
continue;
WARN_ON(s->role.level != PT_PAGE_TABLE_LEVEL);
__kvm_unsync_page(vcpu, s);
@@ -1819,18 +1804,11 @@ static void kvm_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn)
static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
bool can_unsync)
{
- unsigned index;
- struct hlist_head *bucket;
struct kvm_mmu_page *s;
struct hlist_node *node, *n;
bool need_unsync = false;

- index = kvm_page_table_hashfn(gfn);
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry_safe(s, node, n, bucket, hash_link) {
- if (s->gfn != gfn || s->role.direct || s->role.invalid)
- continue;
-
+ for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node, n) {
if (s->role.level != PT_PAGE_TABLE_LEVEL)
return 1;

@@ -2701,8 +2679,6 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
gfn_t gfn = gpa >> PAGE_SHIFT;
struct kvm_mmu_page *sp;
struct hlist_node *node, *n;
- struct hlist_head *bucket;
- unsigned index;
u64 entry, gentry;
u64 *spte;
unsigned offset = offset_in_page(gpa);
@@ -2770,13 +2746,9 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
vcpu->arch.last_pte_updated = NULL;
}
}
- index = kvm_page_table_hashfn(gfn);
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];

restart:
- hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) {
- if (sp->gfn != gfn || sp->role.direct || sp->role.invalid)
- continue;
+ for_each_gfn_indirect_valid_sp(vcpu->kvm, sp, gfn, node, n) {
pte_size = sp->role.cr4_pae ? 8 : 4;
misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1);
misaligned |= bytes < 4;
--
1.6.1.2