[PATCH v5 16/44] KVM: Add a simplified wrapper for registering perf callbacks

Sean Christopherson posted 44 patches 6 months ago
There is a newer version of this series
[PATCH v5 16/44] KVM: Add a simplified wrapper for registering perf callbacks
Posted by Sean Christopherson 6 months ago
Add a parameter-less API for registering perf callbacks in anticipation of
introducing another x86-only parameter for handling mediated PMU PMIs.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/arm64/kvm/arm.c      |  2 +-
 arch/loongarch/kvm/main.c |  2 +-
 arch/riscv/kvm/main.c     |  2 +-
 arch/x86/kvm/x86.c        |  2 +-
 include/linux/kvm_host.h  | 11 +++++++++--
 virt/kvm/kvm_main.c       |  5 +++--
 6 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 888f7c7abf54..6c604b5214f2 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -2328,7 +2328,7 @@ static int __init init_subsystems(void)
 	if (err)
 		goto out;
 
-	kvm_register_perf_callbacks(NULL);
+	kvm_register_perf_callbacks();
 
 out:
 	if (err)
diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
index 80ea63d465b8..f62326fe29fa 100644
--- a/arch/loongarch/kvm/main.c
+++ b/arch/loongarch/kvm/main.c
@@ -394,7 +394,7 @@ static int kvm_loongarch_env_init(void)
 	}
 
 	kvm_init_gcsr_flag();
-	kvm_register_perf_callbacks(NULL);
+	kvm_register_perf_callbacks();
 
 	/* Register LoongArch IPI interrupt controller interface. */
 	ret = kvm_loongarch_register_ipi_device();
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index 67c876de74ef..cbe842c2f615 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -159,7 +159,7 @@ static int __init riscv_kvm_init(void)
 		kvm_info("AIA available with %d guest external interrupts\n",
 			 kvm_riscv_aia_nr_hgei);
 
-	kvm_register_perf_callbacks(NULL);
+	kvm_register_perf_callbacks();
 
 	rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
 	if (rc) {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5af2c5aed0f2..d80bbd5e0859 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9689,7 +9689,7 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
 		set_hv_tscchange_cb(kvm_hyperv_tsc_notifier);
 #endif
 
-	kvm_register_perf_callbacks(ops->handle_intel_pt_intr);
+	__kvm_register_perf_callbacks(ops->handle_intel_pt_intr, NULL);
 
 	if (IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_mmu_enabled)
 		kvm_caps.supported_vm_types |= BIT(KVM_X86_SW_PROTECTED_VM);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 15656b7fba6c..20c50eaa0089 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1731,10 +1731,17 @@ static inline bool kvm_arch_intc_initialized(struct kvm *kvm)
 #ifdef CONFIG_GUEST_PERF_EVENTS
 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu);
 
-void kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void));
+void __kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void),
+				   void (*mediated_pmi_handler)(void));
+
+static inline void kvm_register_perf_callbacks(void)
+{
+	__kvm_register_perf_callbacks(NULL, NULL);
+}
+
 void kvm_unregister_perf_callbacks(void);
 #else
-static inline void kvm_register_perf_callbacks(void *ign) {}
+static inline void kvm_register_perf_callbacks(void) {}
 static inline void kvm_unregister_perf_callbacks(void) {}
 #endif /* CONFIG_GUEST_PERF_EVENTS */
 
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index ecafab2e17d9..d477a7fda0ae 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -6429,10 +6429,11 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = {
 	.handle_mediated_pmi	= NULL,
 };
 
-void kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void))
+void __kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void),
+				   void (*mediated_pmi_handler)(void))
 {
 	kvm_guest_cbs.handle_intel_pt_intr = pt_intr_handler;
-	kvm_guest_cbs.handle_mediated_pmi = NULL;
+	kvm_guest_cbs.handle_mediated_pmi = mediated_pmi_handler;
 
 	perf_register_guest_info_callbacks(&kvm_guest_cbs);
 }
-- 
2.50.1.565.gc32cd1483b-goog
Re: [PATCH v5 16/44] KVM: Add a simplified wrapper for registering perf callbacks
Posted by Anup Patel 5 months, 2 weeks ago
On Thu, Aug 7, 2025 at 1:27 AM Sean Christopherson <seanjc@google.com> wrote:
>
> Add a parameter-less API for registering perf callbacks in anticipation of
> introducing another x86-only parameter for handling mediated PMU PMIs.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <seanjc@google.com>

For KVM RISC-V:
Acked-by: Anup Patel <anup@brainfault.org>

Regards,
Anup

> ---
>  arch/arm64/kvm/arm.c      |  2 +-
>  arch/loongarch/kvm/main.c |  2 +-
>  arch/riscv/kvm/main.c     |  2 +-
>  arch/x86/kvm/x86.c        |  2 +-
>  include/linux/kvm_host.h  | 11 +++++++++--
>  virt/kvm/kvm_main.c       |  5 +++--
>  6 files changed, 16 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
> index 888f7c7abf54..6c604b5214f2 100644
> --- a/arch/arm64/kvm/arm.c
> +++ b/arch/arm64/kvm/arm.c
> @@ -2328,7 +2328,7 @@ static int __init init_subsystems(void)
>         if (err)
>                 goto out;
>
> -       kvm_register_perf_callbacks(NULL);
> +       kvm_register_perf_callbacks();
>
>  out:
>         if (err)
> diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
> index 80ea63d465b8..f62326fe29fa 100644
> --- a/arch/loongarch/kvm/main.c
> +++ b/arch/loongarch/kvm/main.c
> @@ -394,7 +394,7 @@ static int kvm_loongarch_env_init(void)
>         }
>
>         kvm_init_gcsr_flag();
> -       kvm_register_perf_callbacks(NULL);
> +       kvm_register_perf_callbacks();
>
>         /* Register LoongArch IPI interrupt controller interface. */
>         ret = kvm_loongarch_register_ipi_device();
> diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
> index 67c876de74ef..cbe842c2f615 100644
> --- a/arch/riscv/kvm/main.c
> +++ b/arch/riscv/kvm/main.c
> @@ -159,7 +159,7 @@ static int __init riscv_kvm_init(void)
>                 kvm_info("AIA available with %d guest external interrupts\n",
>                          kvm_riscv_aia_nr_hgei);
>
> -       kvm_register_perf_callbacks(NULL);
> +       kvm_register_perf_callbacks();
>
>         rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
>         if (rc) {
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 5af2c5aed0f2..d80bbd5e0859 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -9689,7 +9689,7 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
>                 set_hv_tscchange_cb(kvm_hyperv_tsc_notifier);
>  #endif
>
> -       kvm_register_perf_callbacks(ops->handle_intel_pt_intr);
> +       __kvm_register_perf_callbacks(ops->handle_intel_pt_intr, NULL);
>
>         if (IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_mmu_enabled)
>                 kvm_caps.supported_vm_types |= BIT(KVM_X86_SW_PROTECTED_VM);
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 15656b7fba6c..20c50eaa0089 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1731,10 +1731,17 @@ static inline bool kvm_arch_intc_initialized(struct kvm *kvm)
>  #ifdef CONFIG_GUEST_PERF_EVENTS
>  unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu);
>
> -void kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void));
> +void __kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void),
> +                                  void (*mediated_pmi_handler)(void));
> +
> +static inline void kvm_register_perf_callbacks(void)
> +{
> +       __kvm_register_perf_callbacks(NULL, NULL);
> +}
> +
>  void kvm_unregister_perf_callbacks(void);
>  #else
> -static inline void kvm_register_perf_callbacks(void *ign) {}
> +static inline void kvm_register_perf_callbacks(void) {}
>  static inline void kvm_unregister_perf_callbacks(void) {}
>  #endif /* CONFIG_GUEST_PERF_EVENTS */
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index ecafab2e17d9..d477a7fda0ae 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -6429,10 +6429,11 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = {
>         .handle_mediated_pmi    = NULL,
>  };
>
> -void kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void))
> +void __kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void),
> +                                  void (*mediated_pmi_handler)(void))
>  {
>         kvm_guest_cbs.handle_intel_pt_intr = pt_intr_handler;
> -       kvm_guest_cbs.handle_mediated_pmi = NULL;
> +       kvm_guest_cbs.handle_mediated_pmi = mediated_pmi_handler;
>
>         perf_register_guest_info_callbacks(&kvm_guest_cbs);
>  }
> --
> 2.50.1.565.gc32cd1483b-goog
>