KVM: MMU: don't walk every parent pages while mark unsync
While we mark the parent's unsync_child_bitmap, if the parent is already unsynced, it no need walk it's parent, it can reduce some unnecessary workload Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Родитель
7a8f1a74e4
Коммит
1047df1fb6
|
@ -175,7 +175,7 @@ struct kvm_shadow_walk_iterator {
|
|||
shadow_walk_okay(&(_walker)); \
|
||||
shadow_walk_next(&(_walker)))
|
||||
|
||||
typedef int (*mmu_parent_walk_fn) (struct kvm_mmu_page *sp);
|
||||
typedef void (*mmu_parent_walk_fn) (struct kvm_mmu_page *sp, u64 *spte);
|
||||
|
||||
static struct kmem_cache *pte_chain_cache;
|
||||
static struct kmem_cache *rmap_desc_cache;
|
||||
|
@ -1024,7 +1024,6 @@ static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp,
|
|||
BUG();
|
||||
}
|
||||
|
||||
|
||||
static void mmu_parent_walk(struct kvm_mmu_page *sp, mmu_parent_walk_fn fn)
|
||||
{
|
||||
struct kvm_pte_chain *pte_chain;
|
||||
|
@ -1034,63 +1033,37 @@ static void mmu_parent_walk(struct kvm_mmu_page *sp, mmu_parent_walk_fn fn)
|
|||
|
||||
if (!sp->multimapped && sp->parent_pte) {
|
||||
parent_sp = page_header(__pa(sp->parent_pte));
|
||||
fn(parent_sp);
|
||||
mmu_parent_walk(parent_sp, fn);
|
||||
return;
|
||||
}
|
||||
hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
|
||||
for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
|
||||
if (!pte_chain->parent_ptes[i])
|
||||
break;
|
||||
parent_sp = page_header(__pa(pte_chain->parent_ptes[i]));
|
||||
fn(parent_sp);
|
||||
mmu_parent_walk(parent_sp, fn);
|
||||
}
|
||||
}
|
||||
|
||||
static void kvm_mmu_update_unsync_bitmap(u64 *spte)
|
||||
{
|
||||
unsigned int index;
|
||||
struct kvm_mmu_page *sp = page_header(__pa(spte));
|
||||
|
||||
index = spte - sp->spt;
|
||||
if (!__test_and_set_bit(index, sp->unsync_child_bitmap))
|
||||
sp->unsync_children++;
|
||||
WARN_ON(!sp->unsync_children);
|
||||
}
|
||||
|
||||
static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page *sp)
|
||||
{
|
||||
struct kvm_pte_chain *pte_chain;
|
||||
struct hlist_node *node;
|
||||
int i;
|
||||
|
||||
if (!sp->parent_pte)
|
||||
return;
|
||||
|
||||
if (!sp->multimapped) {
|
||||
kvm_mmu_update_unsync_bitmap(sp->parent_pte);
|
||||
fn(parent_sp, sp->parent_pte);
|
||||
return;
|
||||
}
|
||||
|
||||
hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
|
||||
for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
|
||||
if (!pte_chain->parent_ptes[i])
|
||||
u64 *spte = pte_chain->parent_ptes[i];
|
||||
|
||||
if (!spte)
|
||||
break;
|
||||
kvm_mmu_update_unsync_bitmap(pte_chain->parent_ptes[i]);
|
||||
parent_sp = page_header(__pa(spte));
|
||||
fn(parent_sp, spte);
|
||||
}
|
||||
}
|
||||
|
||||
static int unsync_walk_fn(struct kvm_mmu_page *sp)
|
||||
{
|
||||
kvm_mmu_update_parents_unsync(sp);
|
||||
return 1;
|
||||
}
|
||||
|
||||
static void mark_unsync(struct kvm_mmu_page *sp, u64 *spte);
|
||||
static void kvm_mmu_mark_parents_unsync(struct kvm_mmu_page *sp)
|
||||
{
|
||||
mmu_parent_walk(sp, unsync_walk_fn);
|
||||
kvm_mmu_update_parents_unsync(sp);
|
||||
mmu_parent_walk(sp, mark_unsync);
|
||||
}
|
||||
|
||||
static void mark_unsync(struct kvm_mmu_page *sp, u64 *spte)
|
||||
{
|
||||
unsigned int index;
|
||||
|
||||
index = spte - sp->spt;
|
||||
if (__test_and_set_bit(index, sp->unsync_child_bitmap))
|
||||
return;
|
||||
if (sp->unsync_children++)
|
||||
return;
|
||||
kvm_mmu_mark_parents_unsync(sp);
|
||||
}
|
||||
|
||||
static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
|
||||
|
|
Загрузка…
Ссылка в новой задаче