[PATCH 07/10] KVM: x86: MMU: Move initialization of parent_ptes out from kvm_mmu_alloc_page()

From: Takuya Yoshikawa
Date: Fri Nov 20 2015 - 03:33:39 EST


Make kvm_mmu_alloc_page() do just what its name tells to do, and remove
the extra allocation error check and zero-initialization of parent_ptes:
shadow page headers allocated by kmem_cache_zalloc() are always in the
per-VCPU pools.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@xxxxxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 5b249d4..7f46e3e 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1726,8 +1726,7 @@ static void drop_parent_pte(struct kvm_mmu_page *sp,
mmu_spte_clear_no_track(parent_pte);
}

-static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
- u64 *parent_pte, int direct)
+static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, int direct)
{
struct kvm_mmu_page *sp;

@@ -1743,8 +1742,6 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
* this feature. See the comments in kvm_zap_obsolete_pages().
*/
list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages);
- sp->parent_ptes.val = 0;
- mmu_page_add_parent_pte(vcpu, sp, parent_pte);
kvm_mod_used_mmu_pages(vcpu->kvm, +1);
return sp;
}
@@ -2133,10 +2130,13 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
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 = kvm_mmu_alloc_page(vcpu, direct);
+
+ mmu_page_add_parent_pte(vcpu, sp, parent_pte);
+
sp->gfn = gfn;
sp->role = role;
hlist_add_head(&sp->hash_link,
--
2.1.0

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