[10/15] KVM: Move x86's perf guest info callbacks to generic KVM

Commit Message

Sean Christopherson Aug. 27, 2021, 12:57 a.m. UTC

Move x86's perf guest callbacks into common KVM, as they are semantically
identical to arm64's callbacks (the only other such KVM callbacks).
arm64 will convert to the common versions in a future patch.

Signed-off-by: Sean Christopherson <[e-mail]>
---
 arch/x86/include/asm/kvm_host.h |  1 +
 arch/x86/kvm/x86.c              | 48 +++++----------------------------
 arch/x86/kvm/x86.h              |  6 -----
 include/linux/kvm_host.h        | 12 +++++++++
 virt/kvm/kvm_main.c             | 46 +++++++++++++++++++++++++++++++
 5 files changed, 66 insertions(+), 47 deletions(-)

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 465b35736d9b..63553a1f43ee 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -36,6 +36,7 @@ 
 #include <asm/hyperv-tlfs.h>
 
 #define __KVM_HAVE_ARCH_VCPU_DEBUGFS
+#define __KVM_WANT_PERF_CALLBACKS
 
 #define KVM_MAX_VCPUS 288
 #define KVM_SOFT_MAX_VCPUS 240
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e337aef60793..7cb0f04e24ee 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8264,32 +8264,6 @@  static void kvm_timer_init(void)
 			  kvmclock_cpu_online, kvmclock_cpu_down_prep);
 }
 
-static int kvm_is_in_guest(void)
-{
-	/* x86's callbacks are registered only when handling a guest NMI. */
-	return true;
-}
-
-static int kvm_is_user_mode(void)
-{
-	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
-
-	if (WARN_ON_ONCE(!vcpu))
-		return 0;
-
-	return static_call(kvm_x86_get_cpl)(vcpu) != 0;
-}
-
-static unsigned long kvm_get_guest_ip(void)
-{
-	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
-
-	if (WARN_ON_ONCE(!vcpu))
-		return 0;
-
-	return kvm_rip_read(vcpu);
-}
-
 static void kvm_handle_intel_pt_intr(void)
 {
 	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
@@ -8302,19 +8276,6 @@  static void kvm_handle_intel_pt_intr(void)
 			(unsigned long *)&vcpu->arch.pmu.global_status);
 }
 
-static struct perf_guest_info_callbacks kvm_guest_cbs = {
-	.is_in_guest		= kvm_is_in_guest,
-	.is_user_mode		= kvm_is_user_mode,
-	.get_guest_ip		= kvm_get_guest_ip,
-	.handle_intel_pt_intr	= NULL,
-};
-
-void kvm_register_perf_callbacks(void)
-{
-	__perf_register_guest_info_callbacks(&kvm_guest_cbs);
-}
-EXPORT_SYMBOL_GPL(kvm_register_perf_callbacks);
-
 #ifdef CONFIG_X86_64
 static void pvclock_gtod_update_fn(struct work_struct *work)
 {
@@ -11069,7 +11030,7 @@  int kvm_arch_hardware_setup(void *opaque)
 	kvm_ops_static_call_update();
 
 	if (ops->intel_pt_intr_in_guest && ops->intel_pt_intr_in_guest())
-		kvm_guest_cbs.handle_intel_pt_intr = kvm_handle_intel_pt_intr;
+		kvm_set_intel_pt_intr_handler(kvm_handle_intel_pt_intr);
 
 	if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES))
 		supported_xss = 0;
@@ -11098,7 +11059,7 @@  int kvm_arch_hardware_setup(void *opaque)
 
 void kvm_arch_hardware_unsetup(void)
 {
-	kvm_guest_cbs.handle_intel_pt_intr = NULL;
+	kvm_set_intel_pt_intr_handler(NULL);
 
 	static_call(kvm_x86_hardware_unsetup)();
 }
@@ -11725,6 +11686,11 @@  bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
 	return vcpu->arch.preempted_in_kernel;
 }
 
+unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
+{
+	return kvm_rip_read(vcpu);
+}
+
 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
 {
 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index f13f15d2fab8..e1fe738c3827 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -387,12 +387,6 @@  static inline bool kvm_cstate_in_guest(struct kvm *kvm)
 	return kvm->arch.cstate_in_guest;
 }
 
-void kvm_register_perf_callbacks(void);
-static inline void kvm_unregister_perf_callbacks(void)
-{
-	__perf_unregister_guest_info_callbacks();
-}
-
 static inline void kvm_before_interrupt(struct kvm_vcpu *vcpu, bool is_nmi)
 {
 	WRITE_ONCE(vcpu->arch.handling_nmi_from_guest, is_nmi);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index e4d712e9f760..0db9af0b628c 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1163,6 +1163,18 @@  static inline bool kvm_arch_intc_initialized(struct kvm *kvm)
 }
 #endif
 
+#ifdef __KVM_WANT_PERF_CALLBACKS
+
+void kvm_set_intel_pt_intr_handler(void (*handler)(void));
+unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu);
+
+void kvm_register_perf_callbacks(void);
+static inline void kvm_unregister_perf_callbacks(void)
+{
+	__perf_unregister_guest_info_callbacks();
+}
+#endif
+
 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type);
 void kvm_arch_destroy_vm(struct kvm *kvm);
 void kvm_arch_sync_events(struct kvm *kvm);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3e67c93ca403..13c4f58a75e5 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5460,6 +5460,52 @@  struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
         return &kvm_running_vcpu;
 }
 
+#ifdef __KVM_WANT_PERF_CALLBACKS
+static int kvm_is_in_guest(void)
+{
+	/* Registration of KVM's callback signifies "in guest". */
+	return true;
+}
+
+static int kvm_is_user_mode(void)
+{
+	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
+
+	if (WARN_ON_ONCE(!vcpu))
+		return 0;
+
+	return !kvm_arch_vcpu_in_kernel(vcpu);
+}
+
+static unsigned long kvm_get_guest_ip(void)
+{
+	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
+
+	if (WARN_ON_ONCE(!vcpu))
+		return 0;
+
+	return kvm_arch_vcpu_get_ip(vcpu);
+}
+
+static struct perf_guest_info_callbacks kvm_guest_cbs = {
+	.is_in_guest		= kvm_is_in_guest,
+	.is_user_mode		= kvm_is_user_mode,
+	.get_guest_ip		= kvm_get_guest_ip,
+	.handle_intel_pt_intr	= NULL,
+};
+
+void kvm_set_intel_pt_intr_handler(void (*handler)(void))
+{
+	kvm_guest_cbs.handle_intel_pt_intr = handler;
+}
+
+void kvm_register_perf_callbacks(void)
+{
+	__perf_register_guest_info_callbacks(&kvm_guest_cbs);
+}
+EXPORT_SYMBOL_GPL(kvm_register_perf_callbacks);
+#endif
+
 struct kvm_cpu_compat_check {
 	void *opaque;
 	int *ret;