[ Sorry, missed this one ]

On Wed, Dec 05, 2018 at 04:36:21PM +0100, Vitaly Kuznetsov wrote:
> Turns out we over-engineered Direct Mode for stimers a bit: unlike
> traditional stimers where we may want to try to re-inject the message upon
> EOI, Direct Mode stimers just set the irq in APIC and kvm_apic_set_irq()
> fails only when APIC is disabled (see APIC_DM_FIXED case in
> __apic_accept_irq()). Remove the redundant part.
> 
> Suggested-by: Roman Kagan <rka...@virtuozzo.com>
> Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
> ---
>  arch/x86/kvm/hyperv.c | 36 +++---------------------------------
>  1 file changed, 3 insertions(+), 33 deletions(-)
> 
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index e6a2a085644a..0a16a77e6ac3 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -56,21 +56,8 @@ static inline int synic_get_sint_vector(u64 sint_value)
>  static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
>                                     int vector)
>  {
> -     struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
> -     struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
> -     struct kvm_vcpu_hv_stimer *stimer;
>       int i;
>  
> -     for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++) {
> -             stimer = &hv_vcpu->stimer[i];
> -             if (stimer->config.enable && stimer->config.direct_mode &&
> -                 stimer->config.apic_vector == vector)
> -                     return true;
> -     }
> -
> -     if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
> -             return false;
> -
>       for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
>               if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
>                       return true;
> @@ -96,14 +83,14 @@ static bool synic_has_vector_auto_eoi(struct 
> kvm_vcpu_hv_synic *synic,
>  static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
>                               int vector)
>  {
> +     if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
> +             return;
> +
>       if (synic_has_vector_connected(synic, vector))
>               __set_bit(vector, synic->vec_bitmap);
>       else
>               __clear_bit(vector, synic->vec_bitmap);
>  
> -     if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
> -             return;
> -
>       if (synic_has_vector_auto_eoi(synic, vector))
>               __set_bit(vector, synic->auto_eoi_bitmap);
>       else
> @@ -382,9 +369,7 @@ int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 
> sint)
>  
>  void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
>  {
> -     struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
>       struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
> -     struct kvm_vcpu_hv_stimer *stimer;
>       int i;
>  
>       trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
> @@ -392,14 +377,6 @@ void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int 
> vector)
>       for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
>               if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
>                       kvm_hv_notify_acked_sint(vcpu, i);
> -
> -     for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++) {
> -             stimer = &hv_vcpu->stimer[i];
> -             if (stimer->msg_pending && stimer->config.enable &&
> -                 stimer->config.direct_mode &&
> -                 stimer->config.apic_vector == vector)
> -                     stimer_mark_pending(stimer, false);
> -     }
>  }
>  
>  static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
> @@ -566,8 +543,6 @@ static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
>  static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
>                            bool host)
>  {
> -     struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
> -     struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
>       union hv_stimer_config new_config = {.as_uint64 = config},
>               old_config = {.as_uint64 = stimer->config.as_uint64};
>  
> @@ -580,11 +555,6 @@ static int stimer_set_config(struct kvm_vcpu_hv_stimer 
> *stimer, u64 config,
>               new_config.enable = 0;
>       stimer->config.as_uint64 = new_config.as_uint64;
>  
> -     if (old_config.direct_mode)
> -             synic_update_vector(&hv_vcpu->synic, old_config.apic_vector);
> -     if (new_config.direct_mode)
> -             synic_update_vector(&hv_vcpu->synic, new_config.apic_vector);
> -
>       stimer_mark_pending(stimer, false);
>       return 0;
>  }

As discussed in another thread, it seems worth while to make
stimer_set_config reject vectors 0..15.

Besides I'd rather sqwash this patch into the one that introduced direct
timers, before it reached Linus' tree.

Roman.

Reply via email to