KVM: MMU: split kvm_mmu_free_page

Split kvm_mmu_free_page to kvm_mmu_isolate_page and
kvm_mmu_free_page

One is used to remove the page from cache under mmu lock and the other is
used to free page table out of mmu lock

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Xiao Guangrong 2011-07-12 03:27:14 +08:00 committed by Avi Kivity
parent aa6bd187af
commit bd4c86eaa6

View File

@ -1039,14 +1039,28 @@ static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, int nr)
percpu_counter_add(&kvm_total_used_mmu_pages, nr);
}
static void kvm_mmu_free_page(struct kvm_mmu_page *sp)
/*
* Remove the sp from shadow page cache, after call it,
* we can not find this sp from the cache, and the shadow
* page table is still valid.
* It should be under the protection of mmu lock.
*/
static void kvm_mmu_isolate_page(struct kvm_mmu_page *sp)
{
ASSERT(is_empty_shadow_page(sp->spt));
hlist_del(&sp->hash_link);
list_del(&sp->link);
free_page((unsigned long)sp->spt);
if (!sp->role.direct)
free_page((unsigned long)sp->gfns);
}
/*
* Free the shadow page table and the sp, we can do it
* out of the protection of mmu lock.
*/
static void kvm_mmu_free_page(struct kvm_mmu_page *sp)
{
list_del(&sp->link);
free_page((unsigned long)sp->spt);
kmem_cache_free(mmu_page_header_cache, sp);
}
@ -1678,6 +1692,7 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm,
do {
sp = list_first_entry(invalid_list, struct kvm_mmu_page, link);
WARN_ON(!sp->role.invalid || sp->root_count);
kvm_mmu_isolate_page(sp);
kvm_mmu_free_page(sp);
} while (!list_empty(invalid_list));