diff options
author | David Matlack <dmatlack@google.com> | 2021-06-17 23:19:46 +0000 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-06-18 06:45:46 -0400 |
commit | 0b873fd7fb53ed7343ee7ee166e1373aec02a9cb (patch) | |
tree | 0a8a768eaa17782bf54852d0b95f91f16c654de6 /arch/x86/kvm/mmu/tdp_mmu.h | |
parent | KVM: x86/mmu: Remove redundant is_tdp_mmu_root check (diff) | |
download | linux-dev-0b873fd7fb53ed7343ee7ee166e1373aec02a9cb.tar.xz linux-dev-0b873fd7fb53ed7343ee7ee166e1373aec02a9cb.zip |
KVM: x86/mmu: Remove redundant is_tdp_mmu_enabled check
This check is redundant because the root shadow page will only be a TDP
MMU page if is_tdp_mmu_enabled() returns true, and is_tdp_mmu_enabled()
never changes for the lifetime of a VM.
It's possible that this check was added for performance reasons but it
is unlikely that it is useful in practice since to_shadow_page() is
cheap. That being said, this patch also caches the return value of
is_tdp_mmu_root() in direct_page_fault() since there's no reason to
duplicate the call so many times, so performance is not a concern.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210617231948.2591431-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to '')
-rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.h | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h index 78d8a296f0b6..f6e0667cf4b6 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.h +++ b/arch/x86/kvm/mmu/tdp_mmu.h @@ -86,12 +86,10 @@ void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm); static inline bool is_tdp_mmu_enabled(struct kvm *kvm) { return kvm->arch.tdp_mmu_enabled; } static inline bool is_tdp_mmu_page(struct kvm_mmu_page *sp) { return sp->tdp_mmu_page; } -static inline bool is_tdp_mmu_root(struct kvm *kvm, hpa_t hpa) +static inline bool is_tdp_mmu_root(hpa_t hpa) { struct kvm_mmu_page *sp; - if (!is_tdp_mmu_enabled(kvm)) - return false; if (WARN_ON(!VALID_PAGE(hpa))) return false; |