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Date: Tue, 10 Aug 2021 15:45:54 -0700 From: Sean Christopherson <seanjc@...gle.com> To: Paolo Bonzini <pbonzini@...hat.com> Cc: Sean Christopherson <seanjc@...gle.com>, Vitaly Kuznetsov <vkuznets@...hat.com>, Wanpeng Li <wanpengli@...cent.com>, Jim Mattson <jmattson@...gle.com>, Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org, linux-kernel@...r.kernel.org, Ben Gardon <bgardon@...gle.com> Subject: [PATCH 2/2] KVM: x86/mmu: Drop 'shared' param from tdp_mmu_link_page() Drop @shared from tdp_mmu_link_page() and hardcode it to work for mmu_lock being held for read. The helper has exactly one caller and in all likelihood will only ever have exactly one caller. Even if KVM adds a path to install translations without an initiating page fault, odds are very, very good that the path will just be a wrapper to the "page fault" handler (both SNP and TDX RFCs propose patches to do exactly that). No functional change intended. Cc: Ben Gardon <bgardon@...gle.com> Signed-off-by: Sean Christopherson <seanjc@...gle.com> --- arch/x86/kvm/mmu/tdp_mmu.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index d99e064d366f..c5b901744d15 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -257,26 +257,17 @@ static void handle_changed_spte_dirty_log(struct kvm *kvm, int as_id, gfn_t gfn, * * @kvm: kvm instance * @sp: the new page - * @shared: This operation may not be running under the exclusive use of - * the MMU lock and the operation must synchronize with other - * threads that might be adding or removing pages. * @account_nx: This page replaces a NX large page and should be marked for * eventual reclaim. */ static void tdp_mmu_link_page(struct kvm *kvm, struct kvm_mmu_page *sp, - bool shared, bool account_nx) + bool account_nx) { - if (shared) - spin_lock(&kvm->arch.tdp_mmu_pages_lock); - else - lockdep_assert_held_write(&kvm->mmu_lock); - + spin_lock(&kvm->arch.tdp_mmu_pages_lock); list_add(&sp->link, &kvm->arch.tdp_mmu_pages); if (account_nx) account_huge_nx_page(kvm, sp); - - if (shared) - spin_unlock(&kvm->arch.tdp_mmu_pages_lock); + spin_unlock(&kvm->arch.tdp_mmu_pages_lock); } /** @@ -1062,7 +1053,7 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, !shadow_accessed_mask); if (tdp_mmu_set_spte_atomic_no_dirty_log(vcpu->kvm, &iter, new_spte)) { - tdp_mmu_link_page(vcpu->kvm, sp, true, + tdp_mmu_link_page(vcpu->kvm, sp, huge_page_disallowed && req_level >= iter.level); -- 2.32.0.605.g8dce9f2422-goog
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