Commit fd136902 authored by Takuya Yoshikawa's avatar Takuya Yoshikawa Committed by Paolo Bonzini
Browse files

KVM: x86: MMU: Move mapping_level_dirty_bitmap() call in mapping_level() 



This is necessary to eliminate an extra memory slot search later.

Signed-off-by: default avatarTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 5ed5c5c8

arch/x86/kvm/mmu.c

+14 −15
Original line number Diff line number Diff line
@@ -870,10 +870,16 @@ static bool mapping_level_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t large_gfn) 
	return !gfn_to_memslot_dirty_bitmap(vcpu, large_gfn, true);

}



static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn)

static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn,

			 bool *force_pt_level)

{

	int host_level, level, max_level;



	if (likely(!*force_pt_level))

		*force_pt_level = mapping_level_dirty_bitmap(vcpu, large_gfn);

	if (unlikely(*force_pt_level))

		return PT_PAGE_TABLE_LEVEL;



	host_level = host_mapping_level(vcpu->kvm, large_gfn);



	if (host_level == PT_PAGE_TABLE_LEVEL)
@@ -2962,14 +2968,13 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code, 
{

	int r;

	int level;

	bool force_pt_level;

	bool force_pt_level = false;

	pfn_t pfn;

	unsigned long mmu_seq;

	bool map_writable, write = error_code & PFERR_WRITE_MASK;



	force_pt_level = mapping_level_dirty_bitmap(vcpu, gfn);

	level = mapping_level(vcpu, gfn, &force_pt_level);

	if (likely(!force_pt_level)) {

		level = mapping_level(vcpu, gfn);

		/*

		 * This path builds a PAE pagetable - so we can map

		 * 2mb pages at maximum. Therefore check if the level
@@ -2979,8 +2984,7 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code, 
			level = PT_DIRECTORY_LEVEL;



		gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1);

	} else

		level = PT_PAGE_TABLE_LEVEL;

	}



	if (fast_page_fault(vcpu, v, level, error_code))

		return 0;
@@ -3495,20 +3499,15 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code, 
	if (r)

		return r;



	if (mapping_level_dirty_bitmap(vcpu, gfn) ||

	    !check_hugepage_cache_consistency(vcpu, gfn, PT_DIRECTORY_LEVEL))

		force_pt_level = true;

	else

		force_pt_level = false;



	force_pt_level = !check_hugepage_cache_consistency(vcpu, gfn,

							   PT_DIRECTORY_LEVEL);

	level = mapping_level(vcpu, gfn, &force_pt_level);

	if (likely(!force_pt_level)) {

		level = mapping_level(vcpu, gfn);

		if (level > PT_DIRECTORY_LEVEL &&

		    !check_hugepage_cache_consistency(vcpu, gfn, level))

			level = PT_DIRECTORY_LEVEL;

		gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1);

	} else

		level = PT_PAGE_TABLE_LEVEL;

	}



	if (fast_page_fault(vcpu, gpa, level, error_code))

		return 0;

arch/x86/kvm/paging_tmpl.h

+3 −3
Original line number Diff line number Diff line
@@ -744,9 +744,9 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, 
	      &walker, user_fault, &vcpu->arch.write_fault_to_shadow_pgtable);



	if (walker.level >= PT_DIRECTORY_LEVEL && !is_self_change_mapping) {

		force_pt_level = mapping_level_dirty_bitmap(vcpu, walker.gfn);

		if (!force_pt_level) {

			level = min(walker.level, mapping_level(vcpu, walker.gfn));

		level = mapping_level(vcpu, walker.gfn, &force_pt_level);

		if (likely(!force_pt_level)) {

			level = min(walker.level, level);

			walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1);

		}

	} else