KVM: MMU: remove bypass_guest_pf
The idea is from Avi:
| Maybe it's time to kill off bypass_guest_pf=1. It's not as effective as
| it used to be, since unsync pages always use shadow_trap_nonpresent_pte,
| and since we convert between the two nonpresent_ptes during sync and unsync.
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index fa3b54b..a4565df 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -337,16 +337,11 @@
struct kvm_mmu_page *sp, u64 *spte,
pt_element_t gpte)
{
- u64 nonpresent = shadow_trap_nonpresent_pte;
-
if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL))
goto no_present;
- if (!is_present_gpte(gpte)) {
- if (!sp->unsync)
- nonpresent = shadow_notrap_nonpresent_pte;
+ if (!is_present_gpte(gpte))
goto no_present;
- }
if (!(gpte & PT_ACCESSED_MASK))
goto no_present;
@@ -354,7 +349,7 @@
return false;
no_present:
- drop_spte(vcpu->kvm, spte, nonpresent);
+ drop_spte(vcpu->kvm, spte);
return true;
}
@@ -437,7 +432,7 @@
if (spte == sptep)
continue;
- if (*spte != shadow_trap_nonpresent_pte)
+ if (is_shadow_present_pte(*spte))
continue;
gpte = gptep[i];
@@ -687,11 +682,10 @@
if (is_shadow_present_pte(*sptep)) {
if (is_large_pte(*sptep))
--vcpu->kvm->stat.lpages;
- drop_spte(vcpu->kvm, sptep,
- shadow_trap_nonpresent_pte);
+ drop_spte(vcpu->kvm, sptep);
need_flush = 1;
- } else
- __set_spte(sptep, shadow_trap_nonpresent_pte);
+ }
+
break;
}
@@ -751,36 +745,6 @@
return gpa;
}
-static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
- struct kvm_mmu_page *sp)
-{
- int i, j, offset, r;
- pt_element_t pt[256 / sizeof(pt_element_t)];
- gpa_t pte_gpa;
-
- if (sp->role.direct
- || (PTTYPE == 32 && sp->role.level > PT_PAGE_TABLE_LEVEL)) {
- nonpaging_prefetch_page(vcpu, sp);
- return;
- }
-
- pte_gpa = gfn_to_gpa(sp->gfn);
- if (PTTYPE == 32) {
- offset = sp->role.quadrant << PT64_LEVEL_BITS;
- pte_gpa += offset * sizeof(pt_element_t);
- }
-
- for (i = 0; i < PT64_ENT_PER_PAGE; i += ARRAY_SIZE(pt)) {
- r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa, pt, sizeof pt);
- pte_gpa += ARRAY_SIZE(pt) * sizeof(pt_element_t);
- for (j = 0; j < ARRAY_SIZE(pt); ++j)
- if (r || is_present_gpte(pt[j]))
- sp->spt[i+j] = shadow_trap_nonpresent_pte;
- else
- sp->spt[i+j] = shadow_notrap_nonpresent_pte;
- }
-}
-
/*
* Using the cached information from sp->gfns is safe because:
* - The spte has a reference to the struct page, so the pfn for a given gfn
@@ -833,8 +797,7 @@
}
if (gfn != sp->gfns[i]) {
- drop_spte(vcpu->kvm, &sp->spt[i],
- shadow_trap_nonpresent_pte);
+ drop_spte(vcpu->kvm, &sp->spt[i]);
vcpu->kvm->tlbs_dirty++;
continue;
}