diff mbox series

[v12,82/84] KVM: arm64: Don't mark "struct page" accessed when making SPTE young

Message ID 20240726235234.228822-83-seanjc@google.com (mailing list archive)
State Handled Elsewhere, archived
Headers show
Series KVM: Stop grabbing references to PFNMAP'd pages | expand

Checks

Context Check Description
conchuod/vmtest-fixes-PR fail merge-conflict
conchuod/vmtest-for-next-PR fail PR summary
conchuod/patch-82-test-1 success .github/scripts/patches/tests/build_rv32_defconfig.sh
conchuod/patch-82-test-2 success .github/scripts/patches/tests/build_rv64_clang_allmodconfig.sh
conchuod/patch-82-test-3 success .github/scripts/patches/tests/build_rv64_gcc_allmodconfig.sh
conchuod/patch-82-test-4 success .github/scripts/patches/tests/build_rv64_nommu_k210_defconfig.sh
conchuod/patch-82-test-5 success .github/scripts/patches/tests/build_rv64_nommu_virt_defconfig.sh
conchuod/patch-82-test-6 success .github/scripts/patches/tests/checkpatch.sh
conchuod/patch-82-test-7 success .github/scripts/patches/tests/dtb_warn_rv64.sh
conchuod/patch-82-test-8 success .github/scripts/patches/tests/header_inline.sh
conchuod/patch-82-test-9 success .github/scripts/patches/tests/kdoc.sh
conchuod/patch-82-test-10 success .github/scripts/patches/tests/module_param.sh
conchuod/patch-82-test-11 success .github/scripts/patches/tests/verify_fixes.sh
conchuod/patch-82-test-12 success .github/scripts/patches/tests/verify_signedoff.sh

Commit Message

Sean Christopherson July 26, 2024, 11:52 p.m. UTC
Don't mark pages/folios as accessed in the primary MMU when making a SPTE
young in KVM's secondary MMU, as doing so relies on
kvm_pfn_to_refcounted_page(), and generally speaking is unnecessary and
wasteful.  KVM participates in page aging via mmu_notifiers, so there's no
need to push "accessed" updates to the primary MMU.

Dropping use of kvm_set_pfn_accessed() also paves the way for removing
kvm_pfn_to_refcounted_page() and all its users.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/arm64/include/asm/kvm_pgtable.h | 4 +---
 arch/arm64/kvm/hyp/pgtable.c         | 7 ++-----
 arch/arm64/kvm/mmu.c                 | 6 +-----
 3 files changed, 4 insertions(+), 13 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
index 19278dfe7978..676d80723c38 100644
--- a/arch/arm64/include/asm/kvm_pgtable.h
+++ b/arch/arm64/include/asm/kvm_pgtable.h
@@ -632,10 +632,8 @@  int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size);
  *
  * If there is a valid, leaf page-table entry used to translate @addr, then
  * set the access flag in that entry.
- *
- * Return: The old page-table entry prior to setting the flag, 0 on failure.
  */
-kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr);
+void kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr);
 
 /**
  * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index 9e2bbee77491..6679e02a02c4 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -1287,19 +1287,16 @@  int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size)
 					NULL, NULL, 0);
 }
 
-kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr)
+void kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr)
 {
-	kvm_pte_t pte = 0;
 	int ret;
 
 	ret = stage2_update_leaf_attrs(pgt, addr, 1, KVM_PTE_LEAF_ATTR_LO_S2_AF, 0,
-				       &pte, NULL,
+				       NULL, NULL,
 				       KVM_PGTABLE_WALK_HANDLE_FAULT |
 				       KVM_PGTABLE_WALK_SHARED);
 	if (!ret)
 		dsb(ishst);
-
-	return pte;
 }
 
 struct stage2_age_data {
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 756fc856ab44..8fd8ea5b5795 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1699,18 +1699,14 @@  static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 /* Resolve the access fault by making the page young again. */
 static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
 {
-	kvm_pte_t pte;
 	struct kvm_s2_mmu *mmu;
 
 	trace_kvm_access_fault(fault_ipa);
 
 	read_lock(&vcpu->kvm->mmu_lock);
 	mmu = vcpu->arch.hw_mmu;
-	pte = kvm_pgtable_stage2_mkyoung(mmu->pgt, fault_ipa);
+	kvm_pgtable_stage2_mkyoung(mmu->pgt, fault_ipa);
 	read_unlock(&vcpu->kvm->mmu_lock);
-
-	if (kvm_pte_valid(pte))
-		kvm_set_pfn_accessed(kvm_pte_to_pfn(pte));
 }
 
 /**