From 0375f7fad904b59502341ccecfc8faea70b34c91 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Mon, 28 Nov 2011 20:41:00 +0800 Subject: [PATCH] KVM: MMU: audit: replace mmu audit tracepoint with jump-label The tracepoint is only used to audit mmu code, it should not be exposed to user, let us replace it with jump-label. Signed-off-by: Xiao Guangrong Signed-off-by: Avi Kivity --- arch/x86/kvm/mmu.c | 16 +++++++++++----- arch/x86/kvm/mmu_audit.c | 28 +++++++++++++--------------- arch/x86/kvm/mmutrace.h | 19 ------------------- arch/x86/kvm/paging_tmpl.h | 4 ++-- 4 files changed, 26 insertions(+), 41 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index d737443cdfdb..62f69dbf6b52 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -68,6 +68,12 @@ char *audit_point_name[] = { "post sync" }; +#ifdef CONFIG_KVM_MMU_AUDIT +static void kvm_mmu_audit(struct kvm_vcpu *vcpu, int point); +#else +static void kvm_mmu_audit(struct kvm_vcpu *vcpu, int point) { } +#endif + #undef MMU_DEBUG #ifdef MMU_DEBUG @@ -2852,12 +2858,12 @@ static void mmu_sync_roots(struct kvm_vcpu *vcpu) return; vcpu_clear_mmio_info(vcpu, ~0ul); - trace_kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC); + kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC); if (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL) { hpa_t root = vcpu->arch.mmu.root_hpa; sp = page_header(root); mmu_sync_children(vcpu, sp); - trace_kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); + kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); return; } for (i = 0; i < 4; ++i) { @@ -2869,7 +2875,7 @@ static void mmu_sync_roots(struct kvm_vcpu *vcpu) mmu_sync_children(vcpu, sp); } } - trace_kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); + kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); } void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) @@ -3667,7 +3673,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, spin_lock(&vcpu->kvm->mmu_lock); ++vcpu->kvm->stat.mmu_pte_write; - trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); + kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); mask.cr0_wp = mask.cr4_pae = mask.nxe = 1; for_each_gfn_indirect_valid_sp(vcpu->kvm, sp, gfn, node) { @@ -3700,7 +3706,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, } mmu_pte_write_flush_tlb(vcpu, zap_page, remote_flush, local_flush); kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); - trace_kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE); + kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE); spin_unlock(&vcpu->kvm->mmu_lock); } diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c index 746ec259d024..5df6736a5afb 100644 --- a/arch/x86/kvm/mmu_audit.c +++ b/arch/x86/kvm/mmu_audit.c @@ -224,30 +224,29 @@ static void audit_vcpu_spte(struct kvm_vcpu *vcpu) mmu_spte_walk(vcpu, audit_spte); } -static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int point) +static bool mmu_audit; +static struct jump_label_key mmu_audit_key; + +static void kvm_mmu_audit(struct kvm_vcpu *vcpu, int point) { static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); - if (!__ratelimit(&ratelimit_state)) - return; + if (static_branch((&mmu_audit_key))) { + if (!__ratelimit(&ratelimit_state)) + return; - vcpu->kvm->arch.audit_point = point; - audit_all_active_sps(vcpu->kvm); - audit_vcpu_spte(vcpu); + vcpu->kvm->arch.audit_point = point; + audit_all_active_sps(vcpu->kvm); + audit_vcpu_spte(vcpu); + } } -static bool mmu_audit; - static void mmu_audit_enable(void) { - int ret; - if (mmu_audit) return; - ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); - WARN_ON(ret); - + jump_label_inc(&mmu_audit_key); mmu_audit = true; } @@ -256,8 +255,7 @@ static void mmu_audit_disable(void) if (!mmu_audit) return; - unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); - tracepoint_synchronize_unregister(); + jump_label_dec(&mmu_audit_key); mmu_audit = false; } diff --git a/arch/x86/kvm/mmutrace.h b/arch/x86/kvm/mmutrace.h index eed67f34146d..89fb0e81322a 100644 --- a/arch/x86/kvm/mmutrace.h +++ b/arch/x86/kvm/mmutrace.h @@ -243,25 +243,6 @@ TRACE_EVENT( TP_printk("addr:%llx gfn %llx access %x", __entry->addr, __entry->gfn, __entry->access) ); - -TRACE_EVENT( - kvm_mmu_audit, - TP_PROTO(struct kvm_vcpu *vcpu, int audit_point), - TP_ARGS(vcpu, audit_point), - - TP_STRUCT__entry( - __field(struct kvm_vcpu *, vcpu) - __field(int, audit_point) - ), - - TP_fast_assign( - __entry->vcpu = vcpu; - __entry->audit_point = audit_point; - ), - - TP_printk("vcpu:%d %s", __entry->vcpu->cpu, - audit_point_name[__entry->audit_point]) -); #endif /* _TRACE_KVMMMU_H */ #undef TRACE_INCLUDE_PATH diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 52e9d58cec2b..15610285ebb6 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -632,7 +632,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, if (mmu_notifier_retry(vcpu, mmu_seq)) goto out_unlock; - trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); + kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); kvm_mmu_free_some_pages(vcpu); if (!force_pt_level) transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level); @@ -643,7 +643,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, sptep, *sptep, emulate); ++vcpu->stat.pf_fixed; - trace_kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT); + kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT); spin_unlock(&vcpu->kvm->mmu_lock); return emulate; -- 2.20.1