Re: [PATCH v2] KVM: MMU: optimize pte write path if don't have protectedsp

From: Avi Kivity
Date: Wed May 11 2011 - 12:23:41 EST


On 05/11/2011 05:44 AM, Xiao Guangrong wrote:
Simply return from kvm_mmu_pte_write path if no shadow page is
write-protected, then we can avoid to walk all shadow pages and hold
mmu-lock

@@ -1038,8 +1038,10 @@ static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
hlist_del(&sp->hash_link);
list_del(&sp->link);
free_page((unsigned long)sp->spt);
- if (!sp->role.direct)
+ if (!sp->role.direct) {
free_page((unsigned long)sp->gfns);
+ atomic_dec(&kvm->arch.indirect_shadow_pages);
+ }
kmem_cache_free(mmu_page_header_cache, sp);
kvm_mod_used_mmu_pages(kvm, -1);
}
@@ -1536,6 +1538,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
kvm_sync_pages(vcpu, gfn);

account_shadowed(vcpu->kvm, gfn);
+ atomic_inc(&vcpu->kvm->arch.indirect_shadow_pages);
}

Better in account_shadowed()/unaccount_shadowed(), no?


--
error compiling committee.c: too many arguments to function

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