GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-07-23 15:27:29 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

KVM: x86/mmu: Avoid multiple hash lookups in kvm_get_mmu_page()

Browse source 
Refactor for_each_valid_sp() to take the list of shadow pages instead of
retrieving it from a gfn to avoid doing the gfn->list hash and lookup
multiple times during kvm_get_mmu_page().

Cc: Peter Feiner <pfeiner@google.com>
Cc: Jon Cargille <jcargill@google.com>
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200623194027.23135-2-sean.j.christopherson@intel.com>
Reviewed-By: Jon Cargille <jcargill@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2020-06-23 12:40:26 -07:00 • committed by Paolo Bonzini
parent 4cb5b77eec
commit ac101b7cb1
1 changed files with 9 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

17
arch/x86/kvm/mmu/mmu.c
View file

@ -2243,15 +2243,14 @@ static bool kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp,
static void kvm_mmu_commit_zap_page(struct kvm *kvm,
struct list_head *invalid_list);
#define for_each_valid_sp(_kvm, _sp, _gfn) \
hlist_for_each_entry(_sp, \
&(_kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(_gfn)], hash_link) \
#define for_each_valid_sp(_kvm, _sp, _list) \
hlist_for_each_entry(_sp, _list, hash_link) \
if (is_obsolete_sp((_kvm), (_sp))) { \
} else
#define for_each_gfn_indirect_valid_sp(_kvm, _sp, _gfn) \
for_each_valid_sp(_kvm, _sp, _gfn) \
for_each_valid_sp(_kvm, _sp, \
&(_kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(_gfn)]) \
if ((_sp)->gfn != (_gfn) || (_sp)->role.direct) {} else
static inline bool is_ept_sp(struct kvm_mmu_page *sp)
@ -2462,6 +2461,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
unsigned int access)
{
union kvm_mmu_page_role role;
struct hlist_head *sp_list;
unsigned quadrant;
struct kvm_mmu_page *sp;
bool need_sync = false;
@ -2481,7 +2481,9 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1;
role.quadrant = quadrant;
}
for_each_valid_sp(vcpu->kvm, sp, gfn) {
sp_list = &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)];
for_each_valid_sp(vcpu->kvm, sp, sp_list) {
if (sp->gfn != gfn) {
collisions++;
continue;
@ -2518,8 +2520,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
sp->gfn = gfn;
sp->role = role;
hlist_add_head(&sp->hash_link,
&vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]);
hlist_add_head(&sp->hash_link, sp_list);
if (!direct) {
/*
* we should do write protection before syncing pages