From ca41c34cab1f50f13ab5ac95739483871637a684 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 1 Sep 2021 15:10:22 -0700 Subject: [PATCH] KVM: x86/mmu: Relocate kvm_mmu_page.tdp_mmu_page for better cache locality Move "tdp_mmu_page" into the 1-byte void left by the recently removed "mmio_cached" so that it resides in the first 64 bytes of kvm_mmu_page, i.e. in the same cache line as the most commonly accessed fields. Don't bother wrapping tdp_mmu_page in CONFIG_X86_64, including the field in 32-bit builds doesn't affect the size of kvm_mmu_page, and a future patch can always wrap the field in the unlikely event KVM gains a 1-byte flag that is 32-bit specific. Note, the size of kvm_mmu_page is also unchanged on CONFIG_X86_64=y due to it previously sharing an 8-byte chunk with write_flooding_count. No functional change intended. Signed-off-by: Sean Christopherson Message-Id: <20210901221023.1303578-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/mmu_internal.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index 6b6f108..4e7b634 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -35,6 +35,7 @@ struct kvm_mmu_page { struct hlist_node hash_link; struct list_head lpage_disallowed_link; + bool tdp_mmu_page; bool unsync; u8 mmu_valid_gen; bool lpage_disallowed; /* Can't be replaced by an equiv large page */ @@ -70,8 +71,6 @@ struct kvm_mmu_page { atomic_t write_flooding_count; #ifdef CONFIG_X86_64 - bool tdp_mmu_page; - /* Used for freeing the page asynchronously if it is a TDP MMU page. */ struct rcu_head rcu_head; #endif -- 2.7.4