subject:"\[PATCH v4 3\/3\] KVM\/arm\/arm64\: enable enhanced armv8 fp\/simd lazy switch"

Re: [PATCH v4 3/3] KVM/arm/arm64: enable enhanced armv8 fp/simd lazy switch

2015-12-03 Thread Marc Zyngier

On 14/11/15 22:12, Mario Smarduch wrote:
> This patch tracks armv7 and armv8 fp/simd hardware state with a vcpu lazy 
> flag.
> On vcpu_load for 32 bit guests enable FP access, and later enable fp/simd
> trapping for 32 and 64 bit guests if lazy flag is not set. On first fp/simd 
> access trap to handler to save host and restore guest context, disable 
> trapping and set vcpu lazy flag. On vcpu_put if flag is set save guest and 
> restore host context and also save guest fpexc register.
> 
> Signed-off-by: Mario Smarduch 
> ---
>  arch/arm/include/asm/kvm_host.h   |  3 ++
>  arch/arm/kvm/arm.c| 18 +++--
>  arch/arm64/include/asm/kvm_asm.h  |  2 +
>  arch/arm64/include/asm/kvm_host.h | 17 +++-
>  arch/arm64/kernel/asm-offsets.c   |  1 +
>  arch/arm64/kvm/hyp.S  | 83 
> +--
>  6 files changed, 89 insertions(+), 35 deletions(-)
> 
> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
> index 8fc7a59..6960ff2 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -40,6 +40,8 @@
>  
>  #define KVM_MAX_VCPUS VGIC_V2_MAX_CPUS
>  
> +#define kvm_guest_is32bit(vcpu)  true

This should be defined as an inline function, and placed in
asm/kvm_emulate.h, probably renamed as kvm_guest_vcpu_is_32bit.

> +
>  /*
>   * Reads the host FPEXC register, saves to vcpu context and enables the
>   * FPEXC.
> @@ -260,6 +262,7 @@ void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot);
>  
>  struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);
>  void kvm_restore_host_vfp_state(struct kvm_vcpu *);
> +static inline void kvm_save_guest_fpexc(struct kvm_vcpu *vcpu) {}
>  
>  static inline void kvm_arch_hardware_disable(void) {}
>  static inline void kvm_arch_hardware_unsetup(void) {}
> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
> index cfc348a..7a20530 100644
> --- a/arch/arm/kvm/arm.c
> +++ b/arch/arm/kvm/arm.c
> @@ -292,8 +292,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
>  
>   kvm_arm_set_running_vcpu(vcpu);
>  
> - /* Save and enable FPEXC before we load guest context */
> - kvm_enable_fpexc(vcpu);
> + /*
> +  * For 32bit guest executing on arm64, enable fp/simd access in
> +  * EL2. On arm32 save host fpexc and then enable fp/simd access.
> +  */
> + if (kvm_guest_is32bit(vcpu))
> + kvm_enable_fpexc(vcpu);
>  }
>  
>  void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
> @@ -301,10 +305,18 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
>   /* If the fp/simd registers are dirty save guest, restore host. */
>   if (vcpu->arch.vfp_dirty) {
>   kvm_restore_host_vfp_state(vcpu);
> +
> + /*
> +  * For 32bit guest on arm64 save the guest fpexc register
> +  * in EL2 mode.
> +  */
> + if (kvm_guest_is32bit(vcpu))
> + kvm_save_guest_fpexc(vcpu);
> +
>   vcpu->arch.vfp_dirty = 0;
>   }
>  
> - /* Restore host FPEXC trashed in vcpu_load */
> + /* For arm32 restore host FPEXC trashed in vcpu_load. */
>   kvm_restore_host_fpexc(vcpu);
>  
>   /*
> diff --git a/arch/arm64/include/asm/kvm_asm.h 
> b/arch/arm64/include/asm/kvm_asm.h
> index 5e37710..c589ca9 100644
> --- a/arch/arm64/include/asm/kvm_asm.h
> +++ b/arch/arm64/include/asm/kvm_asm.h
> @@ -117,6 +117,8 @@ extern char __kvm_hyp_vector[];
>  extern void __kvm_flush_vm_context(void);
>  extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
>  extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
> +extern void __kvm_enable_fpexc32(void);
> +extern void __kvm_save_fpexc32(struct kvm_vcpu *vcpu);
>  
>  extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
>  
> diff --git a/arch/arm64/include/asm/kvm_host.h 
> b/arch/arm64/include/asm/kvm_host.h
> index 83e65dd..6e2d6b5 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -41,6 +41,8 @@
>  
>  #define KVM_VCPU_MAX_FEATURES 3
>  
> +#define kvm_guest_is32bit(vcpu)  (!(vcpu->arch.hcr_el2 & HCR_RW))
> +
>  int __attribute_const__ kvm_target_cpu(void);
>  int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
>  int kvm_arch_dev_ioctl_check_extension(long ext);
> @@ -251,9 +253,20 @@ static inline void kvm_arch_hardware_unsetup(void) {}
>  static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>  static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
>  static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
> -static inline void kvm_enable_fpexc(struct kvm_vcpu *vcpu) {}
> -static inline void kvm_restore_host_vfp_state(struct kvm_vcpu *vcpu) {}
> +
> +static inline void kvm_enable_fpexc(struct kvm_vcpu *vcpu)
> +{
> + /* Enable FP/SIMD access from EL2 mode*/
> + kvm_call_hyp(__kvm_enable_fpexc32);
> +}
> +
> +static inline void kvm_save_guest_fpexc(struct kvm_vcpu *vcpu)
> +{

Re: [PATCH v4 3/3] KVM/arm/arm64: enable enhanced armv8 fp/simd lazy switch

2015-12-03 Thread Mario Smarduch



On 12/3/2015 8:13 AM, Marc Zyngier wrote:
> On 14/11/15 22:12, Mario Smarduch wrote:
>> This patch tracks armv7 and armv8 fp/simd hardware state with a vcpu lazy 
>> flag.
>> On vcpu_load for 32 bit guests enable FP access, and later enable fp/simd
>> trapping for 32 and 64 bit guests if lazy flag is not set. On first fp/simd 
>> access trap to handler to save host and restore guest context, disable 
>> trapping and set vcpu lazy flag. On vcpu_put if flag is set save guest and 
>> restore host context and also save guest fpexc register.
>>
>> Signed-off-by: Mario Smarduch 
>> ---
>>  arch/arm/include/asm/kvm_host.h   |  3 ++
>>  arch/arm/kvm/arm.c| 18 +++--
>>  arch/arm64/include/asm/kvm_asm.h  |  2 +
>>  arch/arm64/include/asm/kvm_host.h | 17 +++-
>>  arch/arm64/kernel/asm-offsets.c   |  1 +
>>  arch/arm64/kvm/hyp.S  | 83 
>> +--
>>  6 files changed, 89 insertions(+), 35 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/kvm_host.h 
>> b/arch/arm/include/asm/kvm_host.h
>> index 8fc7a59..6960ff2 100644
>> --- a/arch/arm/include/asm/kvm_host.h
>> +++ b/arch/arm/include/asm/kvm_host.h
>> @@ -40,6 +40,8 @@
>>  
>>  #define KVM_MAX_VCPUS VGIC_V2_MAX_CPUS
>>  
>> +#define kvm_guest_is32bit(vcpu) true
> 
> This should be defined as an inline function, and placed in
> asm/kvm_emulate.h, probably renamed as kvm_guest_vcpu_is_32bit.

Will do, this header file should also resolve my problems in armv7.
> 
>> +
>>  /*
>>   * Reads the host FPEXC register, saves to vcpu context and enables the
>>   * FPEXC.
>> @@ -260,6 +262,7 @@ void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot);
>>  
>>  struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);
>>  void kvm_restore_host_vfp_state(struct kvm_vcpu *);
>> +static inline void kvm_save_guest_fpexc(struct kvm_vcpu *vcpu) {}
>>  
>>  static inline void kvm_arch_hardware_disable(void) {}
>>  static inline void kvm_arch_hardware_unsetup(void) {}
>> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
>> index cfc348a..7a20530 100644
>> --- a/arch/arm/kvm/arm.c
>> +++ b/arch/arm/kvm/arm.c
>> @@ -292,8 +292,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
>>  
>>  kvm_arm_set_running_vcpu(vcpu);
>>  
>> -/* Save and enable FPEXC before we load guest context */
>> -kvm_enable_fpexc(vcpu);
>> +/*
>> + * For 32bit guest executing on arm64, enable fp/simd access in
>> + * EL2. On arm32 save host fpexc and then enable fp/simd access.
>> + */
>> +if (kvm_guest_is32bit(vcpu))
>> +kvm_enable_fpexc(vcpu);
>>  }
>>  
>>  void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
>> @@ -301,10 +305,18 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
>>  /* If the fp/simd registers are dirty save guest, restore host. */
>>  if (vcpu->arch.vfp_dirty) {
>>  kvm_restore_host_vfp_state(vcpu);
>> +
>> +/*
>> + * For 32bit guest on arm64 save the guest fpexc register
>> + * in EL2 mode.
>> + */
>> +if (kvm_guest_is32bit(vcpu))
>> +kvm_save_guest_fpexc(vcpu);
>> +
>>  vcpu->arch.vfp_dirty = 0;
>>  }
>>  
>> -/* Restore host FPEXC trashed in vcpu_load */
>> +/* For arm32 restore host FPEXC trashed in vcpu_load. */
>>  kvm_restore_host_fpexc(vcpu);
>>  
>>  /*
>> diff --git a/arch/arm64/include/asm/kvm_asm.h 
>> b/arch/arm64/include/asm/kvm_asm.h
>> index 5e37710..c589ca9 100644
>> --- a/arch/arm64/include/asm/kvm_asm.h
>> +++ b/arch/arm64/include/asm/kvm_asm.h
>> @@ -117,6 +117,8 @@ extern char __kvm_hyp_vector[];
>>  extern void __kvm_flush_vm_context(void);
>>  extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
>>  extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
>> +extern void __kvm_enable_fpexc32(void);
>> +extern void __kvm_save_fpexc32(struct kvm_vcpu *vcpu);
>>  
>>  extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
>>  
>> diff --git a/arch/arm64/include/asm/kvm_host.h 
>> b/arch/arm64/include/asm/kvm_host.h
>> index 83e65dd..6e2d6b5 100644
>> --- a/arch/arm64/include/asm/kvm_host.h
>> +++ b/arch/arm64/include/asm/kvm_host.h
>> @@ -41,6 +41,8 @@
>>  
>>  #define KVM_VCPU_MAX_FEATURES 3
>>  
>> +#define kvm_guest_is32bit(vcpu) (!(vcpu->arch.hcr_el2 & HCR_RW))
>> +
>>  int __attribute_const__ kvm_target_cpu(void);
>>  int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
>>  int kvm_arch_dev_ioctl_check_extension(long ext);
>> @@ -251,9 +253,20 @@ static inline void kvm_arch_hardware_unsetup(void) {}
>>  static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>>  static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
>>  static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
>> -static inline void kvm_enable_fpexc(struct kvm_vcpu *vcpu) {}
>> -static inline void kvm_restore_host_vfp_state(struct kvm_vcpu *vcpu) {}
>> +
>> +static inline void

[PATCH v4 3/3] KVM/arm/arm64: enable enhanced armv8 fp/simd lazy switch

2015-11-14 Thread Mario Smarduch

This patch tracks armv7 and armv8 fp/simd hardware state with a vcpu lazy flag.
On vcpu_load for 32 bit guests enable FP access, and later enable fp/simd
trapping for 32 and 64 bit guests if lazy flag is not set. On first fp/simd 
access trap to handler to save host and restore guest context, disable 
trapping and set vcpu lazy flag. On vcpu_put if flag is set save guest and 
restore host context and also save guest fpexc register.

Signed-off-by: Mario Smarduch 
---
 arch/arm/include/asm/kvm_host.h   |  3 ++
 arch/arm/kvm/arm.c| 18 +++--
 arch/arm64/include/asm/kvm_asm.h  |  2 +
 arch/arm64/include/asm/kvm_host.h | 17 +++-
 arch/arm64/kernel/asm-offsets.c   |  1 +
 arch/arm64/kvm/hyp.S  | 83 +--
 6 files changed, 89 insertions(+), 35 deletions(-)

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 8fc7a59..6960ff2 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -40,6 +40,8 @@
 
 #define KVM_MAX_VCPUS VGIC_V2_MAX_CPUS
 
+#define kvm_guest_is32bit(vcpu)true
+
 /*
  * Reads the host FPEXC register, saves to vcpu context and enables the
  * FPEXC.
@@ -260,6 +262,7 @@ void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot);
 
 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);
 void kvm_restore_host_vfp_state(struct kvm_vcpu *);
+static inline void kvm_save_guest_fpexc(struct kvm_vcpu *vcpu) {}
 
 static inline void kvm_arch_hardware_disable(void) {}
 static inline void kvm_arch_hardware_unsetup(void) {}
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index cfc348a..7a20530 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -292,8 +292,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
kvm_arm_set_running_vcpu(vcpu);
 
-   /* Save and enable FPEXC before we load guest context */
-   kvm_enable_fpexc(vcpu);
+   /*
+* For 32bit guest executing on arm64, enable fp/simd access in
+* EL2. On arm32 save host fpexc and then enable fp/simd access.
+*/
+   if (kvm_guest_is32bit(vcpu))
+   kvm_enable_fpexc(vcpu);
 }
 
 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
@@ -301,10 +305,18 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
/* If the fp/simd registers are dirty save guest, restore host. */
if (vcpu->arch.vfp_dirty) {
kvm_restore_host_vfp_state(vcpu);
+
+   /*
+* For 32bit guest on arm64 save the guest fpexc register
+* in EL2 mode.
+*/
+   if (kvm_guest_is32bit(vcpu))
+   kvm_save_guest_fpexc(vcpu);
+
vcpu->arch.vfp_dirty = 0;
}
 
-   /* Restore host FPEXC trashed in vcpu_load */
+   /* For arm32 restore host FPEXC trashed in vcpu_load. */
kvm_restore_host_fpexc(vcpu);
 
/*
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 5e37710..c589ca9 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -117,6 +117,8 @@ extern char __kvm_hyp_vector[];
 extern void __kvm_flush_vm_context(void);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
 extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
+extern void __kvm_enable_fpexc32(void);
+extern void __kvm_save_fpexc32(struct kvm_vcpu *vcpu);
 
 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
 
diff --git a/arch/arm64/include/asm/kvm_host.h 
b/arch/arm64/include/asm/kvm_host.h
index 83e65dd..6e2d6b5 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -41,6 +41,8 @@
 
 #define KVM_VCPU_MAX_FEATURES 3
 
+#define kvm_guest_is32bit(vcpu)(!(vcpu->arch.hcr_el2 & HCR_RW))
+
 int __attribute_const__ kvm_target_cpu(void);
 int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
 int kvm_arch_dev_ioctl_check_extension(long ext);
@@ -251,9 +253,20 @@ static inline void kvm_arch_hardware_unsetup(void) {}
 static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
 static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
-static inline void kvm_enable_fpexc(struct kvm_vcpu *vcpu) {}
-static inline void kvm_restore_host_vfp_state(struct kvm_vcpu *vcpu) {}
+
+static inline void kvm_enable_fpexc(struct kvm_vcpu *vcpu)
+{
+   /* Enable FP/SIMD access from EL2 mode*/
+   kvm_call_hyp(__kvm_enable_fpexc32);
+}
+
+static inline void kvm_save_guest_fpexc(struct kvm_vcpu *vcpu)
+{
+   /* Save FPEXEC32_EL2 in EL2 mode */
+   kvm_call_hyp(__kvm_save_fpexc32, vcpu);
+}
 static inline void kvm_restore_host_fpexc(struct kvm_vcpu *vcpu) {}
+void kvm_restore_host_vfp_state(struct kvm_vcpu *vcpu);
 
 void kvm_arm_init_debug(void);
 void kvm_arm_setup_debug(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kernel/asm-offsets.c

Re: [PATCH v4 3/3] KVM/arm/arm64: enable enhanced armv8 fp/simd lazy switch

Re: [PATCH v4 3/3] KVM/arm/arm64: enable enhanced armv8 fp/simd lazy switch

[PATCH v4 3/3] KVM/arm/arm64: enable enhanced armv8 fp/simd lazy switch

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