From 09732d2b4dc5ba9de504711a3ae5aa1199127e6f Mon Sep 17 00:00:00 2001 From: David Matlack Date: Wed, 21 Sep 2022 10:35:38 -0700 Subject: [PATCH] KVM: x86/mmu: Move TDP MMU VM init/uninit behind tdp_mmu_enabled Move kvm_mmu_{init,uninit}_tdp_mmu() behind tdp_mmu_enabled. This makes these functions consistent with the rest of the calls into the TDP MMU from mmu.c, and which is now possible since tdp_mmu_enabled is only modified when the x86 vendor module is loaded. i.e. It will never change during the lifetime of a VM. This change also enabled removing the stub definitions for 32-bit KVM, as the compiler will just optimize the calls out like it does for all the other TDP MMU functions. No functional change intended. Signed-off-by: David Matlack Reviewed-by: Isaku Yamahata Signed-off-by: Paolo Bonzini Message-Id: <20220921173546.2674386-3-dmatlack@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/mmu.c | 11 +++++++---- arch/x86/kvm/mmu/tdp_mmu.c | 6 ------ arch/x86/kvm/mmu/tdp_mmu.h | 7 +++---- 3 files changed, 10 insertions(+), 14 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index bd44e5682a64..31bdf93711a2 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -6035,9 +6035,11 @@ int kvm_mmu_init_vm(struct kvm *kvm) INIT_LIST_HEAD(&kvm->arch.possible_nx_huge_pages); spin_lock_init(&kvm->arch.mmu_unsync_pages_lock); - r = kvm_mmu_init_tdp_mmu(kvm); - if (r < 0) - return r; + if (tdp_mmu_enabled) { + r = kvm_mmu_init_tdp_mmu(kvm); + if (r < 0) + return r; + } node->track_write = kvm_mmu_pte_write; node->track_flush_slot = kvm_mmu_invalidate_zap_pages_in_memslot; @@ -6067,7 +6069,8 @@ void kvm_mmu_uninit_vm(struct kvm *kvm) kvm_page_track_unregister_notifier(kvm, node); - kvm_mmu_uninit_tdp_mmu(kvm); + if (tdp_mmu_enabled) + kvm_mmu_uninit_tdp_mmu(kvm); mmu_free_vm_memory_caches(kvm); } diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 03511e83050f..7e5952e95d3b 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -15,9 +15,6 @@ int kvm_mmu_init_tdp_mmu(struct kvm *kvm) { struct workqueue_struct *wq; - if (!tdp_mmu_enabled) - return 0; - wq = alloc_workqueue("kvm", WQ_UNBOUND|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 0); if (!wq) return -ENOMEM; @@ -42,9 +39,6 @@ static __always_inline bool kvm_lockdep_assert_mmu_lock_held(struct kvm *kvm, void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) { - if (!tdp_mmu_enabled) - return; - /* Also waits for any queued work items. */ destroy_workqueue(kvm->arch.tdp_mmu_zap_wq); diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h index d3714200b932..e4ab2dac269d 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.h +++ b/arch/x86/kvm/mmu/tdp_mmu.h @@ -7,6 +7,9 @@ #include "spte.h" +int kvm_mmu_init_tdp_mmu(struct kvm *kvm); +void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm); + hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu); __must_check static inline bool kvm_tdp_mmu_get_root(struct kvm_mmu_page *root) @@ -68,8 +71,6 @@ u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, u64 addr, u64 *spte); #ifdef CONFIG_X86_64 -int kvm_mmu_init_tdp_mmu(struct kvm *kvm); -void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm); static inline bool is_tdp_mmu_page(struct kvm_mmu_page *sp) { return sp->tdp_mmu_page; } static inline bool is_tdp_mmu(struct kvm_mmu *mmu) @@ -89,8 +90,6 @@ static inline bool is_tdp_mmu(struct kvm_mmu *mmu) return sp && is_tdp_mmu_page(sp) && sp->root_count; } #else -static inline int kvm_mmu_init_tdp_mmu(struct kvm *kvm) { return 0; } -static inline void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) {} static inline bool is_tdp_mmu_page(struct kvm_mmu_page *sp) { return false; } static inline bool is_tdp_mmu(struct kvm_mmu *mmu) { return false; } #endif -- 2.25.1