[PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-03-31 Thread Yang Zhang 
From: Yang Zhang 

Signed-off-by: Yang Zhang 
---
 arch/x86/kvm/lapic.c |9 +
 arch/x86/kvm/lapic.h |2 ++
 virt/kvm/ioapic.c|   43 +++
 virt/kvm/ioapic.h|1 +
 4 files changed, 55 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 96ab160..9c041fa 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void *bitmap)
return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
 }
 
+bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
+{
+   struct kvm_lapic *apic = vcpu->arch.apic;
+
+   return apic_test_vector(vector, apic->regs + APIC_ISR) ||
+   apic_test_vector(vector, apic->regs + APIC_IRR);
+}
+
 static inline void apic_set_vector(int vec, void *bitmap)
 {
set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
@@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
apic->highest_isr_cache = -1;
kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic));
kvm_make_request(KVM_REQ_EVENT, vcpu);
+   kvm_rtc_irq_restore(vcpu);
 }
 
 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 967519c..004d2ad 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct kvm_vcpu 
*vcpu)
return vcpu->arch.apic->pending_events;
 }
 
+bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
+
 #endif
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 8664812..0b12b17 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct kvm_ioapic 
*ioapic,
return result;
 }
 
+static void rtc_irq_reset(struct kvm_ioapic *ioapic)
+{
+   ioapic->rtc_status.pending_eoi = 0;
+   bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
+}
+
+static void rtc_irq_restore(struct kvm_ioapic *ioapic)
+{
+   struct kvm_vcpu *vcpu;
+   int vector, i, pending_eoi = 0;
+
+   if (RTC_GSI >= IOAPIC_NUM_PINS)
+   return;
+
+   vector = ioapic->redirtbl[RTC_GSI].fields.vector;
+   kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
+   if (kvm_apic_pending_eoi(vcpu, vector)) {
+   pending_eoi++;
+   __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
+   }
+   }
+   ioapic->rtc_status.pending_eoi = pending_eoi;
+}
+
+void kvm_rtc_irq_restore(struct kvm_vcpu *vcpu)
+{
+   struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
+   int vector;
+
+   if (!ioapic)
+   return;
+
+   spin_lock(&ioapic->lock);
+   vector = ioapic->redirtbl[RTC_GSI].fields.vector;
+   if (kvm_apic_pending_eoi(vcpu, vector)) {
+   __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
+   ioapic->rtc_status.pending_eoi++;
+   }
+   spin_unlock(&ioapic->lock);
+}
+
 static int ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx)
 {
union kvm_ioapic_redirect_entry *pent;
@@ -431,6 +472,7 @@ void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
ioapic->ioregsel = 0;
ioapic->irr = 0;
ioapic->id = 0;
+   rtc_irq_reset(ioapic);
update_handled_vectors(ioapic);
 }
 
@@ -496,6 +538,7 @@ int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state 
*state)
spin_lock(&ioapic->lock);
memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
update_handled_vectors(ioapic);
+   rtc_irq_restore(ioapic);
kvm_ioapic_make_eoibitmap_request(kvm);
spin_unlock(&ioapic->lock);
return 0;
diff --git a/virt/kvm/ioapic.h b/virt/kvm/ioapic.h
index 761e5b5..2692873 100644
--- a/virt/kvm/ioapic.h
+++ b/virt/kvm/ioapic.h
@@ -79,6 +79,7 @@ static inline struct kvm_ioapic *ioapic_irqchip(struct kvm 
*kvm)
return kvm->arch.vioapic;
 }
 
+void kvm_rtc_irq_restore(struct kvm_vcpu *vcpu);
 int kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int short_hand, int dest, int dest_mode);
 int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2);
-- 
1.7.1

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Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-04 Thread Gleb Natapov 
On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
> From: Yang Zhang 
> 
> Signed-off-by: Yang Zhang 
> ---
>  arch/x86/kvm/lapic.c |9 +
>  arch/x86/kvm/lapic.h |2 ++
>  virt/kvm/ioapic.c|   43 +++
>  virt/kvm/ioapic.h|1 +
>  4 files changed, 55 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 96ab160..9c041fa 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void *bitmap)
>   return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>  }
>  
> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
> +{
> + struct kvm_lapic *apic = vcpu->arch.apic;
> +
> + return apic_test_vector(vector, apic->regs + APIC_ISR) ||
> + apic_test_vector(vector, apic->regs + APIC_IRR);
> +}
> +
>  static inline void apic_set_vector(int vec, void *bitmap)
>  {
>   set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
>   apic->highest_isr_cache = -1;
>   kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic));
>   kvm_make_request(KVM_REQ_EVENT, vcpu);
> + kvm_rtc_irq_restore(vcpu);
>  }
>  
>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> index 967519c..004d2ad 100644
> --- a/arch/x86/kvm/lapic.h
> +++ b/arch/x86/kvm/lapic.h
> @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct kvm_vcpu 
> *vcpu)
>   return vcpu->arch.apic->pending_events;
>  }
>  
> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
> +
>  #endif
> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
> index 8664812..0b12b17 100644
> --- a/virt/kvm/ioapic.c
> +++ b/virt/kvm/ioapic.c
> @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct 
> kvm_ioapic *ioapic,
>   return result;
>  }
>  
> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
> +{
> + ioapic->rtc_status.pending_eoi = 0;
> + bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
> +}
> +
> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
> +{
> + struct kvm_vcpu *vcpu;
> + int vector, i, pending_eoi = 0;
> +
> + if (RTC_GSI >= IOAPIC_NUM_PINS)
> + return;
> +
> + vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> + kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
> + if (kvm_apic_pending_eoi(vcpu, vector)) {
> + pending_eoi++;
> + __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
You should cleat dest_map at the beginning to get rid of stale bits.

> + }
> + }
> + ioapic->rtc_status.pending_eoi = pending_eoi;
> +}
> +
> +void kvm_rtc_irq_restore(struct kvm_vcpu *vcpu)
> +{
> + struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
> + int vector;
> +
> + if (!ioapic)
> + return;
> +
Can this be called if ioapic == NULL?
Should check for if (RTC_GSI >= IOAPIC_NUM_PINS) here too.

> + spin_lock(&ioapic->lock);
> + vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> + if (kvm_apic_pending_eoi(vcpu, vector)) {
> + __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
> + ioapic->rtc_status.pending_eoi++;
The bit may have been set already. The logic should be:

new_val = kvm_apic_pending_eoi(vcpu, vector)
old_val = set_bit(vcpu_id, dest_map)

if (new_val == old_val)
return;

if (new_val) {
__set_bit(vcpu_id, dest_map);
pending_eoi++;
} else {
__clear_bit(vcpu_id, dest_map);
pending_eoi--;
}

The naming of above two functions are not good either. Call
them something like kvm_rtc_eoi_tracking_restore_all() and
kvm_rtc_eoi_tracking_restore_one().  And _all should call _one() for
each vcpu. Make __rtc_irq_eoi_tracking_restore_one() that does not
take ioapic lock and call it from kvm_rtc_eoi_tracking_restore_one()
surrounded by locks.

--
Gleb.
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RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-06 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-04:
> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
>> From: Yang Zhang 
>> 
>> Signed-off-by: Yang Zhang 
>> ---
>>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |2 ++
>>  virt/kvm/ioapic.c|   43
>>  +++ virt/kvm/ioapic.h|   
>>  1 + 4 files changed, 55 insertions(+), 0 deletions(-)
>> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
>> index 96ab160..9c041fa 100644
>> --- a/arch/x86/kvm/lapic.c
>> +++ b/arch/x86/kvm/lapic.c
>> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void *bitmap)
>>  return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
>> +{
>> +struct kvm_lapic *apic = vcpu->arch.apic;
>> +
>> +return apic_test_vector(vector, apic->regs + APIC_ISR) ||
>> +apic_test_vector(vector, apic->regs + APIC_IRR);
>> +}
>> +
>>  static inline void apic_set_vector(int vec, void *bitmap)
>>  {
>>  set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct kvm_vcpu
> *vcpu,
>>  apic->highest_isr_cache = -1;
>>  kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
>>  apic_find_highest_isr(apic));   kvm_make_request(KVM_REQ_EVENT, vcpu);
>>  +   kvm_rtc_irq_restore(vcpu); }
>>  
>>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
>> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
>> index 967519c..004d2ad 100644
>> --- a/arch/x86/kvm/lapic.h
>> +++ b/arch/x86/kvm/lapic.h
>> @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
> kvm_vcpu *vcpu)
>>  return vcpu->arch.apic->pending_events;
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
>> +
>>  #endif
>> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
>> index 8664812..0b12b17 100644
>> --- a/virt/kvm/ioapic.c
>> +++ b/virt/kvm/ioapic.c
>> @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
> kvm_ioapic *ioapic,
>>  return result;
>>  }
>> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
>> +{
>> +ioapic->rtc_status.pending_eoi = 0;
>> +bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
>> +}
>> +
>> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
>> +{
>> +struct kvm_vcpu *vcpu;
>> +int vector, i, pending_eoi = 0;
>> +
>> +if (RTC_GSI >= IOAPIC_NUM_PINS)
>> +return;
>> +
>> +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>> +kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
>> +if (kvm_apic_pending_eoi(vcpu, vector)) {
>> +pending_eoi++;
>> +__set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
> You should cleat dest_map at the beginning to get rid of stale bits.
I thought kvm_set_ioapic is called only after save/restore or migration. And 
the ioapic should be reset successfully before call it. So the dest_map is 
empty before call rtc_irq_restore().
But it is possible kvm_set_ioapic is called beside save/restore or migration. 
Right?

> 
>> +}
>> +}
>> +ioapic->rtc_status.pending_eoi = pending_eoi;
>> +}
>> +
>> +void kvm_rtc_irq_restore(struct kvm_vcpu *vcpu)
>> +{
>> +struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
>> +int vector;
>> +
>> +if (!ioapic)
>> +return;
>> +
> Can this be called if ioapic == NULL?
Yes. IIRC, unit test will test lapic function without ioapic.

> Should check for if (RTC_GSI >= IOAPIC_NUM_PINS) here too.
Not necessary. kvm_rtc_irq_restore is called from "arch/x86/" and we have the 
defination:
#ifdef CONFIG_X86
#define RTC_GSI 8

The check will be false always. As the logic you suggested below, this check is 
necessary for _all() not _one();

> 
>> +spin_lock(&ioapic->lock);
>> +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>> +if (kvm_apic_pending_eoi(vcpu, vector)) {
>> +__set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
>> +ioapic->rtc_status.pending_eoi++;
> The bit may have been set already. The logic should be:
Right.

>
> 
> new_val = kvm_apic_pending_eoi(vcpu, vector)
> old_val = set_bit(vcpu_id, dest_map)
> 
> if (new_val == old_val)
>   return;
> 
> if (new_val) {
>   __set_bit(vcpu_id, dest_map);
>   pending_eoi++;
> } else {
>   __clear_bit(vcpu_id, dest_map);
>   pending_eoi--;
> }
> 
> The naming of above two functions are not good either. Call
> them something like kvm_rtc_eoi_tracking_restore_all() and
> kvm_rtc_eoi_tracking_restore_one().  And _all should call _one() for
> each vcpu. Make __rtc_irq_eoi_tracking_restore_one() that does not
> take ioapic lock and call it from kvm_rtc_eoi_tracking_restore_one()
> surrounded by locks.
Ok. Just confirm whether I am understanding correct:

kvm_rtc_eoi_tracking_restore_all():
{
for_each_vcpu:
kvm_rtc_eoi_tracking_restore_one():
}

kvm_rtc_eoi_tracking_restore_one():
{
lock();
__rtc_irq_e

Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Gleb Natapov 
On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
> Gleb Natapov wrote on 2013-04-04:
> > On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
> >> From: Yang Zhang 
> >> 
> >> Signed-off-by: Yang Zhang 
> >> ---
> >>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |2 ++
> >>  virt/kvm/ioapic.c|   43
> >>  +++ virt/kvm/ioapic.h|   
> >>  1 + 4 files changed, 55 insertions(+), 0 deletions(-)
> >> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> >> index 96ab160..9c041fa 100644
> >> --- a/arch/x86/kvm/lapic.c
> >> +++ b/arch/x86/kvm/lapic.c
> >> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void 
> >> *bitmap)
> >>return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
> >> +{
> >> +  struct kvm_lapic *apic = vcpu->arch.apic;
> >> +
> >> +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
> >> +  apic_test_vector(vector, apic->regs + APIC_IRR);
> >> +}
> >> +
> >>  static inline void apic_set_vector(int vec, void *bitmap)
> >>  {
> >>set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct kvm_vcpu
> > *vcpu,
> >>apic->highest_isr_cache = -1;
> >>kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
> >>  apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT, vcpu);
> >>  + kvm_rtc_irq_restore(vcpu); }
> >>  
> >>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
> >> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> >> index 967519c..004d2ad 100644
> >> --- a/arch/x86/kvm/lapic.h
> >> +++ b/arch/x86/kvm/lapic.h
> >> @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
> > kvm_vcpu *vcpu)
> >>return vcpu->arch.apic->pending_events;
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
> >> +
> >>  #endif
> >> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
> >> index 8664812..0b12b17 100644
> >> --- a/virt/kvm/ioapic.c
> >> +++ b/virt/kvm/ioapic.c
> >> @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
> > kvm_ioapic *ioapic,
> >>return result;
> >>  }
> >> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
> >> +{
> >> +  ioapic->rtc_status.pending_eoi = 0;
> >> +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
> >> +}
> >> +
> >> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
> >> +{
> >> +  struct kvm_vcpu *vcpu;
> >> +  int vector, i, pending_eoi = 0;
> >> +
> >> +  if (RTC_GSI >= IOAPIC_NUM_PINS)
> >> +  return;
> >> +
> >> +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> >> +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
> >> +  if (kvm_apic_pending_eoi(vcpu, vector)) {
> >> +  pending_eoi++;
> >> +  __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
> > You should cleat dest_map at the beginning to get rid of stale bits.
> I thought kvm_set_ioapic is called only after save/restore or migration. And 
> the ioapic should be reset successfully before call it. So the dest_map is 
> empty before call rtc_irq_restore().
> But it is possible kvm_set_ioapic is called beside save/restore or migration. 
> Right?
> 
First of all userspace should not care when it calls kvm_set_ioapic()
the kernel need to do the right thing. Second, believe it or not,
kvm_ioapic_reset() is not called during system reset. Instead userspace
reset it by calling kvm_set_ioapic() with ioapic state after reset.

> > 
> >> +  }
> >> +  }
> >> +  ioapic->rtc_status.pending_eoi = pending_eoi;
> >> +}
> >> +
> >> +void kvm_rtc_irq_restore(struct kvm_vcpu *vcpu)
> >> +{
> >> +  struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
> >> +  int vector;
> >> +
> >> +  if (!ioapic)
> >> +  return;
> >> +
> > Can this be called if ioapic == NULL?
> Yes. IIRC, unit test will test lapic function without ioapic.
Unit test is a guest code. This has nothing to do with a guest code.
Unit test is not the one who creates lapic.

> 
> > Should check for if (RTC_GSI >= IOAPIC_NUM_PINS) here too.
> Not necessary. kvm_rtc_irq_restore is called from "arch/x86/" and we have the 
> defination:
> #ifdef CONFIG_X86
> #define RTC_GSI 8
> 
> The check will be false always. As the logic you suggested below, this check 
> is necessary for _all() not _one();
OK.

> 
> > 
> >> +  spin_lock(&ioapic->lock);
> >> +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> >> +  if (kvm_apic_pending_eoi(vcpu, vector)) {
> >> +  __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
> >> +  ioapic->rtc_status.pending_eoi++;
> > The bit may have been set already. The logic should be:
> Right.
> 
> >
> > 
> > new_val = kvm_apic_pending_eoi(vcpu, vector)
> > old_val = set_bit(vcpu_id, dest_map)
> > 
> > if (new_val == old_val)
> > return;
> > 
> > if (new_val) {
> > __set_bit(vcpu_id, dest_map);
> > pending_eoi++;
> >

RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-04:
>>> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
 From: Yang Zhang 
 
 Signed-off-by: Yang Zhang 
 ---
  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |2 ++
  virt/kvm/ioapic.c|   43
  +++ virt/kvm/ioapic.h | 1 +
  4 files changed, 55 insertions(+), 0 deletions(-)
 diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
 index 96ab160..9c041fa 100644
 --- a/arch/x86/kvm/lapic.c
 +++ b/arch/x86/kvm/lapic.c
 @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void 
 *bitmap)
return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  }
 +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
 +{
 +  struct kvm_lapic *apic = vcpu->arch.apic;
 +
 +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
 +  apic_test_vector(vector, apic->regs + APIC_IRR);
 +}
 +
  static inline void apic_set_vector(int vec, void *bitmap)
  {
set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
 @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> kvm_vcpu
>>> *vcpu,
apic->highest_isr_cache = -1;
kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
  apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT,
  vcpu); +  kvm_rtc_irq_restore(vcpu); }
  
  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
 diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
 index 967519c..004d2ad 100644
 --- a/arch/x86/kvm/lapic.h
 +++ b/arch/x86/kvm/lapic.h
 @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
>>> kvm_vcpu *vcpu)
return vcpu->arch.apic->pending_events;
  }
 +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
 +
  #endif
 diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
 index 8664812..0b12b17 100644
 --- a/virt/kvm/ioapic.c
 +++ b/virt/kvm/ioapic.c
 @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
>>> kvm_ioapic *ioapic,
return result;
  }
 +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
 +{
 +  ioapic->rtc_status.pending_eoi = 0;
 +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
 +}
 +
 +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
 +{
 +  struct kvm_vcpu *vcpu;
 +  int vector, i, pending_eoi = 0;
 +
 +  if (RTC_GSI >= IOAPIC_NUM_PINS)
 +  return;
 +
 +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
 +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
 +  if (kvm_apic_pending_eoi(vcpu, vector)) {
 +  pending_eoi++;
 +  __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
>>> You should cleat dest_map at the beginning to get rid of stale bits.
>> I thought kvm_set_ioapic is called only after save/restore or migration. And 
>> the
> ioapic should be reset successfully before call it. So the dest_map is empty
> before call rtc_irq_restore().
>> But it is possible kvm_set_ioapic is called beside save/restore or
>> migration. Right?
>> 
> First of all userspace should not care when it calls kvm_set_ioapic()
> the kernel need to do the right thing. Second, believe it or not,
> kvm_ioapic_reset() is not called during system reset. Instead userspace
> reset it by calling kvm_set_ioapic() with ioapic state after reset.
Ok. I see. As the logic you suggested, it will clear dest_map if no pending eoi 
in vcpu, so we don't need to do it again.

> 
>>> 
 +  }
 +  }
 +  ioapic->rtc_status.pending_eoi = pending_eoi;
 +}
 +
 +void kvm_rtc_irq_restore(struct kvm_vcpu *vcpu)
 +{
 +  struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
 +  int vector;
 +
 +  if (!ioapic)
 +  return;
 +
>>> Can this be called if ioapic == NULL?
>> Yes. IIRC, unit test will test lapic function without ioapic.
> Unit test is a guest code. This has nothing to do with a guest code.
> Unit test is not the one who creates lapic.
Ok. Then !ioapic is unnecessary.

>> 
>>> Should check for if (RTC_GSI >= IOAPIC_NUM_PINS) here too.
>> Not necessary. kvm_rtc_irq_restore is called from "arch/x86/" and we
>> have the defination: #ifdef CONFIG_X86 #define RTC_GSI 8
>> 
>> The check will be false always. As the logic you suggested below, this check 
>> is
> necessary for _all() not _one();
> OK.
> 
>> 
>>> 
 +  spin_lock(&ioapic->lock);
 +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
 +  if (kvm_apic_pending_eoi(vcpu, vector)) {
 +  __set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
 +  ioapic->rtc_status.pending_eoi++;
>>> The bit may have been set already. The logic should be:
>> Right.
>> 
>>> 
>>> 
>>> ne

Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Gleb Natapov 
On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
> Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-04:
> >>> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
>  From: Yang Zhang 
>  
>  Signed-off-by: Yang Zhang 
>  ---
>   arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |2 ++
>   virt/kvm/ioapic.c|   43
>   +++ virt/kvm/ioapic.h | 1 +
>   4 files changed, 55 insertions(+), 0 deletions(-)
>  diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
>  index 96ab160..9c041fa 100644
>  --- a/arch/x86/kvm/lapic.c
>  +++ b/arch/x86/kvm/lapic.c
>  @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void 
>  *bitmap)
>   return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>   }
>  +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
>  +{
>  +struct kvm_lapic *apic = vcpu->arch.apic;
>  +
>  +return apic_test_vector(vector, apic->regs + APIC_ISR) ||
>  +apic_test_vector(vector, apic->regs + APIC_IRR);
>  +}
>  +
>   static inline void apic_set_vector(int vec, void *bitmap)
>   {
>   set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>  @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> > kvm_vcpu
> >>> *vcpu,
>   apic->highest_isr_cache = -1;
>   kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
>   apic_find_highest_isr(apic));   kvm_make_request(KVM_REQ_EVENT,
>   vcpu); +kvm_rtc_irq_restore(vcpu); }
>   
>   void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
>  diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
>  index 967519c..004d2ad 100644
>  --- a/arch/x86/kvm/lapic.h
>  +++ b/arch/x86/kvm/lapic.h
>  @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
> >>> kvm_vcpu *vcpu)
>   return vcpu->arch.apic->pending_events;
>   }
>  +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
>  +
>   #endif
>  diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
>  index 8664812..0b12b17 100644
>  --- a/virt/kvm/ioapic.c
>  +++ b/virt/kvm/ioapic.c
>  @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
> >>> kvm_ioapic *ioapic,
>   return result;
>   }
>  +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
>  +{
>  +ioapic->rtc_status.pending_eoi = 0;
>  +bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
>  +}
>  +
>  +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
>  +{
>  +struct kvm_vcpu *vcpu;
>  +int vector, i, pending_eoi = 0;
>  +
>  +if (RTC_GSI >= IOAPIC_NUM_PINS)
>  +return;
>  +
>  +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>  +kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
>  +if (kvm_apic_pending_eoi(vcpu, vector)) {
>  +pending_eoi++;
>  +__set_bit(vcpu->vcpu_id, 
>  ioapic->rtc_status.dest_map);
> >>> You should cleat dest_map at the beginning to get rid of stale bits.
> >> I thought kvm_set_ioapic is called only after save/restore or migration. 
> >> And the
> > ioapic should be reset successfully before call it. So the dest_map is empty
> > before call rtc_irq_restore().
> >> But it is possible kvm_set_ioapic is called beside save/restore or
> >> migration. Right?
> >> 
> > First of all userspace should not care when it calls kvm_set_ioapic()
> > the kernel need to do the right thing. Second, believe it or not,
> > kvm_ioapic_reset() is not called during system reset. Instead userspace
> > reset it by calling kvm_set_ioapic() with ioapic state after reset.
> Ok. I see. As the logic you suggested, it will clear dest_map if no pending 
> eoi in vcpu, so we don't need to do it again.
> 
You again rely on userspace doing thing in certain manner. What is
set_lapic() is never called? Kernel internal state have to be correct
after each ioctl call.

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RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-04:
> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
>> From: Yang Zhang 
>> 
>> Signed-off-by: Yang Zhang 
>> ---
>>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |2
>>  ++ virt/kvm/ioapic.c|   43
>>  +++ virt/kvm/ioapic.h | 1
>>  + 4 files changed, 55 insertions(+), 0 deletions(-)
>> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
>> index 96ab160..9c041fa 100644
>> --- a/arch/x86/kvm/lapic.c
>> +++ b/arch/x86/kvm/lapic.c
>> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> *bitmap)
>>  return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
>> +{
>> +struct kvm_lapic *apic = vcpu->arch.apic;
>> +
>> +return apic_test_vector(vector, apic->regs + APIC_ISR) ||
>> +apic_test_vector(vector, apic->regs + APIC_IRR);
>> +}
>> +
>>  static inline void apic_set_vector(int vec, void *bitmap)
>>  {
>>  set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
>>> kvm_vcpu
> *vcpu,
>>  apic->highest_isr_cache = -1;
>>  kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
>>  apic_find_highest_isr(apic));   kvm_make_request(KVM_REQ_EVENT,
>>  vcpu); +kvm_rtc_irq_restore(vcpu); }
>>  
>>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
>> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
>> index 967519c..004d2ad 100644
>> --- a/arch/x86/kvm/lapic.h
>> +++ b/arch/x86/kvm/lapic.h
>> @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
> kvm_vcpu *vcpu)
>>  return vcpu->arch.apic->pending_events;
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
>> +
>>  #endif
>> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
>> index 8664812..0b12b17 100644
>> --- a/virt/kvm/ioapic.c
>> +++ b/virt/kvm/ioapic.c
>> @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
> kvm_ioapic *ioapic,
>>  return result;
>>  }
>> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
>> +{
>> +ioapic->rtc_status.pending_eoi = 0;
>> +bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
>> +}
>> +
>> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
>> +{
>> +struct kvm_vcpu *vcpu;
>> +int vector, i, pending_eoi = 0;
>> +
>> +if (RTC_GSI >= IOAPIC_NUM_PINS)
>> +return;
>> +
>> +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>> +kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
>> +if (kvm_apic_pending_eoi(vcpu, vector)) {
>> +pending_eoi++;
>> +__set_bit(vcpu->vcpu_id, 
>> ioapic->rtc_status.dest_map);
> You should cleat dest_map at the beginning to get rid of stale bits.
 I thought kvm_set_ioapic is called only after save/restore or migration. 
 And
> the
>>> ioapic should be reset successfully before call it. So the dest_map is empty
>>> before call rtc_irq_restore().
 But it is possible kvm_set_ioapic is called beside save/restore or
 migration. Right?
 
>>> First of all userspace should not care when it calls kvm_set_ioapic()
>>> the kernel need to do the right thing. Second, believe it or not,
>>> kvm_ioapic_reset() is not called during system reset. Instead userspace
>>> reset it by calling kvm_set_ioapic() with ioapic state after reset.
>> Ok. I see. As the logic you suggested, it will clear dest_map if no
>> pending eoi in vcpu, so we don't need to do it again.
>> 
> You again rely on userspace doing thing in certain manner. What is
> set_lapic() is never called? Kernel internal state have to be correct
> after each ioctl call.
Sorry. I cannot figure out what's the problem if don't clear dest_map? Can you 
elaborate it?

Best regards,
Yang


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Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Gleb Natapov 
On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
> Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-07:
> >>> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
>  Gleb Natapov wrote on 2013-04-04:
> > On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
> >> From: Yang Zhang 
> >> 
> >> Signed-off-by: Yang Zhang 
> >> ---
> >>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |2
> >>  ++ virt/kvm/ioapic.c|   43
> >>  +++ virt/kvm/ioapic.h | 1
> >>  + 4 files changed, 55 insertions(+), 0 deletions(-)
> >> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> >> index 96ab160..9c041fa 100644
> >> --- a/arch/x86/kvm/lapic.c
> >> +++ b/arch/x86/kvm/lapic.c
> >> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> > *bitmap)
> >>return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
> >> +{
> >> +  struct kvm_lapic *apic = vcpu->arch.apic;
> >> +
> >> +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
> >> +  apic_test_vector(vector, apic->regs + APIC_IRR);
> >> +}
> >> +
> >>  static inline void apic_set_vector(int vec, void *bitmap)
> >>  {
> >>set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> >>> kvm_vcpu
> > *vcpu,
> >>apic->highest_isr_cache = -1;
> >>kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
> >>  apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT,
> >>  vcpu); +  kvm_rtc_irq_restore(vcpu); }
> >>  
> >>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
> >> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> >> index 967519c..004d2ad 100644
> >> --- a/arch/x86/kvm/lapic.h
> >> +++ b/arch/x86/kvm/lapic.h
> >> @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
> > kvm_vcpu *vcpu)
> >>return vcpu->arch.apic->pending_events;
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
> >> +
> >>  #endif
> >> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
> >> index 8664812..0b12b17 100644
> >> --- a/virt/kvm/ioapic.c
> >> +++ b/virt/kvm/ioapic.c
> >> @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
> > kvm_ioapic *ioapic,
> >>return result;
> >>  }
> >> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
> >> +{
> >> +  ioapic->rtc_status.pending_eoi = 0;
> >> +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
> >> +}
> >> +
> >> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
> >> +{
> >> +  struct kvm_vcpu *vcpu;
> >> +  int vector, i, pending_eoi = 0;
> >> +
> >> +  if (RTC_GSI >= IOAPIC_NUM_PINS)
> >> +  return;
> >> +
> >> +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> >> +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
> >> +  if (kvm_apic_pending_eoi(vcpu, vector)) {
> >> +  pending_eoi++;
> >> +  __set_bit(vcpu->vcpu_id, 
> >> ioapic->rtc_status.dest_map);
> > You should cleat dest_map at the beginning to get rid of stale bits.
>  I thought kvm_set_ioapic is called only after save/restore or migration. 
>  And
> > the
> >>> ioapic should be reset successfully before call it. So the dest_map is 
> >>> empty
> >>> before call rtc_irq_restore().
>  But it is possible kvm_set_ioapic is called beside save/restore or
>  migration. Right?
>  
> >>> First of all userspace should not care when it calls kvm_set_ioapic()
> >>> the kernel need to do the right thing. Second, believe it or not,
> >>> kvm_ioapic_reset() is not called during system reset. Instead userspace
> >>> reset it by calling kvm_set_ioapic() with ioapic state after reset.
> >> Ok. I see. As the logic you suggested, it will clear dest_map if no
> >> pending eoi in vcpu, so we don't need to do it again.
> >> 
> > You again rely on userspace doing thing in certain manner. What is
> > set_lapic() is never called? Kernel internal state have to be correct
> > after each ioctl call.
> Sorry. I cannot figure out what's the problem if don't clear dest_map? Can 
> you elaborate it?
> 
What is not obvious about it? If there is a bit in dest_map that should
be cleared after rtc_irq_restore() it will not.

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RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-04:
>>> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
 From: Yang Zhang 
 
 Signed-off-by: Yang Zhang 
 ---
  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h | 2
  ++ virt/kvm/ioapic.c|   43
  +++ virt/kvm/ioapic.h |
  1 + 4 files changed, 55 insertions(+), 0 deletions(-)
 diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
 index 96ab160..9c041fa 100644
 --- a/arch/x86/kvm/lapic.c
 +++ b/arch/x86/kvm/lapic.c
 @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
>>> *bitmap)
return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  }
 +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
 +{
 +  struct kvm_lapic *apic = vcpu->arch.apic;
 +
 +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
 +  apic_test_vector(vector, apic->regs + APIC_IRR);
 +}
 +
  static inline void apic_set_vector(int vec, void *bitmap)
  {
set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
 @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> kvm_vcpu
>>> *vcpu,
apic->highest_isr_cache = -1;
kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
  apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT,
  vcpu); +  kvm_rtc_irq_restore(vcpu); }
  
  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
 diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
 index 967519c..004d2ad 100644
 --- a/arch/x86/kvm/lapic.h
 +++ b/arch/x86/kvm/lapic.h
 @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
>>> kvm_vcpu *vcpu)
return vcpu->arch.apic->pending_events;
  }
 +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
 +
  #endif
 diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
 index 8664812..0b12b17 100644
 --- a/virt/kvm/ioapic.c
 +++ b/virt/kvm/ioapic.c
 @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
>>> kvm_ioapic *ioapic,
return result;
  }
 +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
 +{
 +  ioapic->rtc_status.pending_eoi = 0;
 +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
 +}
 +
 +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
 +{
 +  struct kvm_vcpu *vcpu;
 +  int vector, i, pending_eoi = 0;
 +
 +  if (RTC_GSI >= IOAPIC_NUM_PINS)
 +  return;
 +
 +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
 +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
 +  if (kvm_apic_pending_eoi(vcpu, vector)) {
 +  pending_eoi++;
 +  __set_bit(vcpu->vcpu_id,
> ioapic->rtc_status.dest_map);
>>> You should cleat dest_map at the beginning to get rid of stale bits.
>> I thought kvm_set_ioapic is called only after save/restore or migration.
> And
>>> the
> ioapic should be reset successfully before call it. So the dest_map is 
> empty
> before call rtc_irq_restore().
>> But it is possible kvm_set_ioapic is called beside save/restore or
>> migration. Right?
>> 
> First of all userspace should not care when it calls kvm_set_ioapic()
> the kernel need to do the right thing. Second, believe it or not,
> kvm_ioapic_reset() is not called during system reset. Instead userspace
> reset it by calling kvm_set_ioapic() with ioapic state after reset.
 Ok. I see. As the logic you suggested, it will clear dest_map if no
 pending eoi in vcpu, so we don't need to do it again.
 
>>> You again rely on userspace doing thing in certain manner. What is
>>> set_lapic() is never called? Kernel internal state have to be correct
>>> after each ioctl call.
>> Sorry. I cannot figure out what's the problem if don't clear dest_map?
>> Can you elaborate it?
>> 
> What is not obvious about it? If there is a bit in dest_map that should
> be cleared after rtc_irq_restore() it will not.
Why it will not? If new_val is false, and the old_val is true. __clear_bit() 
will clear the dest_map. Am I wrong?

new_val = kvm_apic_pending_eoi(vcpu, vector);
old_val = test_bit(vcpu->vcpu_id, io

Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Gleb Natapov 
On Sun, Apr 07, 2013 at 01:16:51PM +, Zhang, Yang Z wrote:
> Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-07:
> >>> On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
>  Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-04:
> >>> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
>  From: Yang Zhang 
>  
>  Signed-off-by: Yang Zhang 
>  ---
>   arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h | 2
>   ++ virt/kvm/ioapic.c|   43
>   +++ virt/kvm/ioapic.h |
>   1 + 4 files changed, 55 insertions(+), 0 deletions(-)
>  diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
>  index 96ab160..9c041fa 100644
>  --- a/arch/x86/kvm/lapic.c
>  +++ b/arch/x86/kvm/lapic.c
>  @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> >>> *bitmap)
>   return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>   }
>  +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
>  +{
>  +struct kvm_lapic *apic = vcpu->arch.apic;
>  +
>  +return apic_test_vector(vector, apic->regs + APIC_ISR) ||
>  +apic_test_vector(vector, apic->regs + APIC_IRR);
>  +}
>  +
>   static inline void apic_set_vector(int vec, void *bitmap)
>   {
>   set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>  @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> > kvm_vcpu
> >>> *vcpu,
>   apic->highest_isr_cache = -1;
>   kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
>   apic_find_highest_isr(apic));   kvm_make_request(KVM_REQ_EVENT,
>   vcpu); +kvm_rtc_irq_restore(vcpu); }
>   
>   void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
>  diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
>  index 967519c..004d2ad 100644
>  --- a/arch/x86/kvm/lapic.h
>  +++ b/arch/x86/kvm/lapic.h
>  @@ -170,4 +170,6 @@ static inline bool kvm_apic_has_events(struct
> >>> kvm_vcpu *vcpu)
>   return vcpu->arch.apic->pending_events;
>   }
>  +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
>  +
>   #endif
>  diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
>  index 8664812..0b12b17 100644
>  --- a/virt/kvm/ioapic.c
>  +++ b/virt/kvm/ioapic.c
>  @@ -90,6 +90,47 @@ static unsigned long ioapic_read_indirect(struct
> >>> kvm_ioapic *ioapic,
>   return result;
>   }
>  +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
>  +{
>  +ioapic->rtc_status.pending_eoi = 0;
>  +bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
>  +}
>  +
>  +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
>  +{
>  +struct kvm_vcpu *vcpu;
>  +int vector, i, pending_eoi = 0;
>  +
>  +if (RTC_GSI >= IOAPIC_NUM_PINS)
>  +return;
>  +
>  +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>  +kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
>  +if (kvm_apic_pending_eoi(vcpu, vector)) {
>  +pending_eoi++;
>  +__set_bit(vcpu->vcpu_id,
> > ioapic->rtc_status.dest_map);
> >>> You should cleat dest_map at the beginning to get rid of stale bits.
> >> I thought kvm_set_ioapic is called only after save/restore or 
> >> migration.
> > And
> >>> the
> > ioapic should be reset successfully before call it. So the dest_map is 
> > empty
> > before call rtc_irq_restore().
> >> But it is possible kvm_set_ioapic is called beside save/restore or
> >> migration. Right?
> >> 
> > First of all userspace should not care when it calls kvm_set_ioapic()
> > the kernel need to do the right thing. Second, believe it or not,
> > kvm_ioapic_reset() is not called during system reset. Instead userspace
> > reset it by calling kvm_set_ioapic() with ioapic state after reset.
>  Ok. I see. As the logic you suggested, it will clear dest_map if no
>  pending eoi in vcpu, so we don't need to do it again.
>  
> >>> You again rely on userspace doing thing in certain manner. What is
> >>> set_lapic() is never called? Kernel internal state have to be correct
> >>> after each ioctl call.
> >> Sorry. I cannot figure out what's the problem if don't clear dest_map?
> >> Can you elaborate it?
> >> 
> > What is not obvious about it? If there is a bit in dest_map that should
> > b

RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 01:16:51PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-04:
> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
>> From: Yang Zhang 
>> 
>> Signed-off-by: Yang Zhang 
>> ---
>>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h | 2
>>  ++ virt/kvm/ioapic.c|   43
>>  +++ virt/kvm/ioapic.h
>>  | 1 + 4 files changed, 55 insertions(+), 0 deletions(-)
>> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
>> index 96ab160..9c041fa 100644
>> --- a/arch/x86/kvm/lapic.c
>> +++ b/arch/x86/kvm/lapic.c
>> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> *bitmap)
>>  return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
>> +{
>> +struct kvm_lapic *apic = vcpu->arch.apic;
>> +
>> +return apic_test_vector(vector, apic->regs + APIC_ISR) ||
>> +apic_test_vector(vector, apic->regs + APIC_IRR);
>> +}
>> +
>>  static inline void apic_set_vector(int vec, void *bitmap)
>>  {
>>  set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
>>> kvm_vcpu
> *vcpu,
>>  apic->highest_isr_cache = -1;
>>  kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
>>  apic_find_highest_isr(apic));   kvm_make_request(KVM_REQ_EVENT,
>>  vcpu); +kvm_rtc_irq_restore(vcpu); }
>>  
>>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
>> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
>> index 967519c..004d2ad 100644
>> --- a/arch/x86/kvm/lapic.h
>> +++ b/arch/x86/kvm/lapic.h
>> @@ -170,4 +170,6 @@ static inline bool
> kvm_apic_has_events(struct
> kvm_vcpu *vcpu)
>>  return vcpu->arch.apic->pending_events;
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
>> +
>>  #endif
>> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
>> index 8664812..0b12b17 100644
>> --- a/virt/kvm/ioapic.c
>> +++ b/virt/kvm/ioapic.c
>> @@ -90,6 +90,47 @@ static unsigned long
> ioapic_read_indirect(struct
> kvm_ioapic *ioapic,
>>  return result;
>>  }
>> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
>> +{
>> +ioapic->rtc_status.pending_eoi = 0;
>> +bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
>> +}
>> +
>> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
>> +{
>> +struct kvm_vcpu *vcpu;
>> +int vector, i, pending_eoi = 0;
>> +
>> +if (RTC_GSI >= IOAPIC_NUM_PINS)
>> +return;
>> +
>> +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>> +kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
>> +if (kvm_apic_pending_eoi(vcpu, vector)) {
>> +pending_eoi++;
>> +__set_bit(vcpu->vcpu_id,
>>> ioapic->rtc_status.dest_map);
> You should cleat dest_map at the beginning to get rid of stale bits.
 I thought kvm_set_ioapic is called only after save/restore or 
 migration.
>>> And
> the
>>> ioapic should be reset successfully before call it. So the
>>> dest_map is empty before call rtc_irq_restore().
 But it is possible kvm_set_ioapic is called beside save/restore or
 migration. Right?
 
>>> First of all userspace should not care when it calls kvm_set_ioapic()
>>> the kernel need to do the right thing. Second, believe it or not,
>>> kvm_ioapic_reset() is not called during system reset. Instead userspace
>>> reset it by calling kvm_set_ioapic() with ioapic state after reset.
>> Ok. I see. As the logic you suggested, it will clear dest_map if no
>> pending eoi in vcpu, so we don't need to do it again.
>> 
> You again rely on userspace doing thing in certain manner. What is
> set_lapic() is never called? Kernel internal state have to be correct
> after each ioctl call.
 Sorry. I cannot figure out what's the problem if don't clear dest_map?
 Can you elaborate it?
 
>>> What is not obvious about it? If there is a b

Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-07 Thread Gleb Natapov 
On Sun, Apr 07, 2013 at 01:46:57PM +, Zhang, Yang Z wrote:
> Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 01:16:51PM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-07:
> >>> On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
>  Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-07:
> >>> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
>  Gleb Natapov wrote on 2013-04-04:
> > On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
> >> From: Yang Zhang 
> >> 
> >> Signed-off-by: Yang Zhang 
> >> ---
> >>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h | 2
> >>  ++ virt/kvm/ioapic.c|   43
> >>  +++ virt/kvm/ioapic.h
> >>  | 1 + 4 files changed, 55 insertions(+), 0 deletions(-)
> >> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> >> index 96ab160..9c041fa 100644
> >> --- a/arch/x86/kvm/lapic.c
> >> +++ b/arch/x86/kvm/lapic.c
> >> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> > *bitmap)
> >>return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
> >> +{
> >> +  struct kvm_lapic *apic = vcpu->arch.apic;
> >> +
> >> +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
> >> +  apic_test_vector(vector, apic->regs + APIC_IRR);
> >> +}
> >> +
> >>  static inline void apic_set_vector(int vec, void *bitmap)
> >>  {
> >>set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> >>> kvm_vcpu
> > *vcpu,
> >>apic->highest_isr_cache = -1;
> >>kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
> >>  apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT,
> >>  vcpu); +  kvm_rtc_irq_restore(vcpu); }
> >>  
> >>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
> >> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> >> index 967519c..004d2ad 100644
> >> --- a/arch/x86/kvm/lapic.h
> >> +++ b/arch/x86/kvm/lapic.h
> >> @@ -170,4 +170,6 @@ static inline bool
> > kvm_apic_has_events(struct
> > kvm_vcpu *vcpu)
> >>return vcpu->arch.apic->pending_events;
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
> >> +
> >>  #endif
> >> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
> >> index 8664812..0b12b17 100644
> >> --- a/virt/kvm/ioapic.c
> >> +++ b/virt/kvm/ioapic.c
> >> @@ -90,6 +90,47 @@ static unsigned long
> > ioapic_read_indirect(struct
> > kvm_ioapic *ioapic,
> >>return result;
> >>  }
> >> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
> >> +{
> >> +  ioapic->rtc_status.pending_eoi = 0;
> >> +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
> >> +}
> >> +
> >> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
> >> +{
> >> +  struct kvm_vcpu *vcpu;
> >> +  int vector, i, pending_eoi = 0;
> >> +
> >> +  if (RTC_GSI >= IOAPIC_NUM_PINS)
> >> +  return;
> >> +
> >> +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> >> +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
> >> +  if (kvm_apic_pending_eoi(vcpu, vector)) {
> >> +  pending_eoi++;
> >> +  __set_bit(vcpu->vcpu_id,
> >>> ioapic->rtc_status.dest_map);
> > You should cleat dest_map at the beginning to get rid of stale bits.
>  I thought kvm_set_ioapic is called only after save/restore or 
>  migration.
> >>> And
> > the
> >>> ioapic should be reset successfully before call it. So the
> >>> dest_map is empty before call rtc_irq_restore().
>  But it is possible kvm_set_ioapic is called beside save/restore or
>  migration. Right?
>  
> >>> First of all userspace should not care when it calls kvm_set_ioapic()
> >>> the kernel need to do the right thing. Second, believe it or not,
> >>> kvm_ioapic_reset() is not called during system reset. Instead 
> >>> userspace
> >>> reset it by calling kvm_set_ioapic() with ioapic state after reset.
> >> Ok. I see. As the logic you suggested, it will clear dest_map if no
> >> pending eoi in vcpu, so we don't need to do it again.
> >> 
> > You again rely on userspace doing thing in certain manner. What is
> > set_lapic() is

RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-08 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 01:16:51PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-04:
> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
>> From: Yang Zhang 
>> 
>> Signed-off-by: Yang Zhang 
>> ---
>>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h | 2
>>  ++ virt/kvm/ioapic.c|   43
>>  +++ virt/kvm/ioapic.h
>>  | 1 + 4 files changed, 55 insertions(+), 0 deletions(-)
>> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
>> index 96ab160..9c041fa 100644
>> --- a/arch/x86/kvm/lapic.c
>> +++ b/arch/x86/kvm/lapic.c
>> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> *bitmap)
>>  return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
>> +{
>> +struct kvm_lapic *apic = vcpu->arch.apic;
>> +
>> +return apic_test_vector(vector, apic->regs + APIC_ISR) ||
>> +apic_test_vector(vector, apic->regs + APIC_IRR);
>> +}
>> +
>>  static inline void apic_set_vector(int vec, void *bitmap)
>>  {
>>  set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
>> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
>>> kvm_vcpu
> *vcpu,
>>  apic->highest_isr_cache = -1;
>>  kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
>>  apic_find_highest_isr(apic));   kvm_make_request(KVM_REQ_EVENT,
>>  vcpu); +kvm_rtc_irq_restore(vcpu); }
>>  
>>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
>> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
>> index 967519c..004d2ad 100644
>> --- a/arch/x86/kvm/lapic.h
>> +++ b/arch/x86/kvm/lapic.h
>> @@ -170,4 +170,6 @@ static inline bool
> kvm_apic_has_events(struct
> kvm_vcpu *vcpu)
>>  return vcpu->arch.apic->pending_events;
>>  }
>> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
>> +
>>  #endif
>> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
>> index 8664812..0b12b17 100644
>> --- a/virt/kvm/ioapic.c
>> +++ b/virt/kvm/ioapic.c
>> @@ -90,6 +90,47 @@ static unsigned long
> ioapic_read_indirect(struct
> kvm_ioapic *ioapic,
>>  return result;
>>  }
>> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
>> +{
>> +ioapic->rtc_status.pending_eoi = 0;
>> +bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
>> +}
>> +
>> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
>> +{
>> +struct kvm_vcpu *vcpu;
>> +int vector, i, pending_eoi = 0;
>> +
>> +if (RTC_GSI >= IOAPIC_NUM_PINS)
>> +return;
>> +
>> +vector = ioapic->redirtbl[RTC_GSI].fields.vector;
>> +kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
>> +if (kvm_apic_pending_eoi(vcpu, vector)) {
>> +pending_eoi++;
>> +__set_bit(vcpu->vcpu_id,
>>> ioapic->rtc_status.dest_map);
> You should cleat dest_map at the beginning to get rid of stale bits.
 I thought kvm_set_ioapic is called only after save/restore or 
 migration.
>>> And
> the
>>> ioapic should be reset successfully before call it. So the
>>> dest_map is empty before call rtc_irq_restore().
 But it is possible kvm_set_ioapic is called beside save/restore or
 migration. Right?
 
>>> First of all userspace should not care when it calls kvm_set_ioapic()
>>> the kernel need to do the right thing. Second, believe it or not,
>>> kvm_ioapic_reset() is not called during system reset. Instead userspace
>>> reset it by calling kvm_set_ioapic() with ioapic state after reset.
>> Ok. I see. As the logic you suggested, it will clear dest_map if no
>> pending eoi in vcpu, so we don't need to do it again.
>> 
> You again rely on userspace doing thing in certain manner. What is
> set_lapic() is never called? Kernel internal state have to be correct
> after each ioctl call.
 Sorry. I cannot figure out what's the problem if don't clear dest_map?
 Can you elaborate it?
 
>>> What is not obvious about it? If there is a b

Re: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-08 Thread Gleb Natapov 
On Mon, Apr 08, 2013 at 11:21:34AM +, Zhang, Yang Z wrote:
> Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 01:16:51PM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-07:
> >>> On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
>  Gleb Natapov wrote on 2013-04-07:
> > On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
> >> Gleb Natapov wrote on 2013-04-07:
> >>> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
>  Gleb Natapov wrote on 2013-04-04:
> > On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
> >> From: Yang Zhang 
> >> 
> >> Signed-off-by: Yang Zhang 
> >> ---
> >>  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h | 2
> >>  ++ virt/kvm/ioapic.c|   43
> >>  +++ virt/kvm/ioapic.h
> >>  | 1 + 4 files changed, 55 insertions(+), 0 deletions(-)
> >> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> >> index 96ab160..9c041fa 100644
> >> --- a/arch/x86/kvm/lapic.c
> >> +++ b/arch/x86/kvm/lapic.c
> >> @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec, void
> > *bitmap)
> >>return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
> >> +{
> >> +  struct kvm_lapic *apic = vcpu->arch.apic;
> >> +
> >> +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
> >> +  apic_test_vector(vector, apic->regs + APIC_IRR);
> >> +}
> >> +
> >>  static inline void apic_set_vector(int vec, void *bitmap)
> >>  {
> >>set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
> >> @@ -1665,6 +1673,7 @@ void kvm_apic_post_state_restore(struct
> >>> kvm_vcpu
> > *vcpu,
> >>apic->highest_isr_cache = -1;
> >>kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
> >>  apic_find_highest_isr(apic)); kvm_make_request(KVM_REQ_EVENT,
> >>  vcpu); +  kvm_rtc_irq_restore(vcpu); }
> >>  
> >>  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
> >> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> >> index 967519c..004d2ad 100644
> >> --- a/arch/x86/kvm/lapic.h
> >> +++ b/arch/x86/kvm/lapic.h
> >> @@ -170,4 +170,6 @@ static inline bool
> > kvm_apic_has_events(struct
> > kvm_vcpu *vcpu)
> >>return vcpu->arch.apic->pending_events;
> >>  }
> >> +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
> >> +
> >>  #endif
> >> diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
> >> index 8664812..0b12b17 100644
> >> --- a/virt/kvm/ioapic.c
> >> +++ b/virt/kvm/ioapic.c
> >> @@ -90,6 +90,47 @@ static unsigned long
> > ioapic_read_indirect(struct
> > kvm_ioapic *ioapic,
> >>return result;
> >>  }
> >> +static void rtc_irq_reset(struct kvm_ioapic *ioapic)
> >> +{
> >> +  ioapic->rtc_status.pending_eoi = 0;
> >> +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
> >> +}
> >> +
> >> +static void rtc_irq_restore(struct kvm_ioapic *ioapic)
> >> +{
> >> +  struct kvm_vcpu *vcpu;
> >> +  int vector, i, pending_eoi = 0;
> >> +
> >> +  if (RTC_GSI >= IOAPIC_NUM_PINS)
> >> +  return;
> >> +
> >> +  vector = ioapic->redirtbl[RTC_GSI].fields.vector;
> >> +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
> >> +  if (kvm_apic_pending_eoi(vcpu, vector)) {
> >> +  pending_eoi++;
> >> +  __set_bit(vcpu->vcpu_id,
> >>> ioapic->rtc_status.dest_map);
> > You should cleat dest_map at the beginning to get rid of stale bits.
>  I thought kvm_set_ioapic is called only after save/restore or 
>  migration.
> >>> And
> > the
> >>> ioapic should be reset successfully before call it. So the
> >>> dest_map is empty before call rtc_irq_restore().
>  But it is possible kvm_set_ioapic is called beside save/restore or
>  migration. Right?
>  
> >>> First of all userspace should not care when it calls kvm_set_ioapic()
> >>> the kernel need to do the right thing. Second, believe it or not,
> >>> kvm_ioapic_reset() is not called during system reset. Instead 
> >>> userspace
> >>> reset it by calling kvm_set_ioapic() with ioapic state after reset.
> >> Ok. I see. As the logic you suggested, it will clear dest_map if no
> >> pending eoi in vcpu, so we don't need to do it again.
> >> 
> > You again rely on userspace doing thing in certain manner. What is
> > set_lapic() is

RE: [PATCH v7 4/7] KVM: Add reset/restore rtc_status support

2013-04-08 Thread Zhang, Yang Z 
Gleb Natapov wrote on 2013-04-08:
> On Mon, Apr 08, 2013 at 11:21:34AM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 01:16:51PM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 01:05:02PM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-07:
>>> On Sun, Apr 07, 2013 at 12:39:32PM +, Zhang, Yang Z wrote:
 Gleb Natapov wrote on 2013-04-07:
> On Sun, Apr 07, 2013 at 02:30:15AM +, Zhang, Yang Z wrote:
>> Gleb Natapov wrote on 2013-04-04:
>>> On Mon, Apr 01, 2013 at 08:40:13AM +0800, Yang Zhang wrote:
 From: Yang Zhang 
 
 Signed-off-by: Yang Zhang 
 ---
  arch/x86/kvm/lapic.c |9 + arch/x86/kvm/lapic.h |
  2 ++ virt/kvm/ioapic.c|   43
  +++
  virt/kvm/ioapic.h | 1 + 4 files changed, 55 insertions(+), 0
  deletions(-)
 diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
 index 96ab160..9c041fa 100644
 --- a/arch/x86/kvm/lapic.c
 +++ b/arch/x86/kvm/lapic.c
 @@ -94,6 +94,14 @@ static inline int apic_test_vector(int vec,
> void
>>> *bitmap)
return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
  }
 +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
 +{
 +  struct kvm_lapic *apic = vcpu->arch.apic;
 +
 +  return apic_test_vector(vector, apic->regs + APIC_ISR) ||
 +  apic_test_vector(vector, apic->regs + APIC_IRR);
 +}
 +
  static inline void apic_set_vector(int vec, void *bitmap)
  {
set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
 @@ -1665,6 +1673,7 @@ void
> kvm_apic_post_state_restore(struct
> kvm_vcpu
>>> *vcpu,
apic->highest_isr_cache = -1;
kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
  apic_find_highest_isr(apic));
kvm_make_request(KVM_REQ_EVENT, vcpu);
  + kvm_rtc_irq_restore(vcpu); }
  
  void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
 diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
 index 967519c..004d2ad 100644
 --- a/arch/x86/kvm/lapic.h
 +++ b/arch/x86/kvm/lapic.h
 @@ -170,4 +170,6 @@ static inline bool
>>> kvm_apic_has_events(struct
>>> kvm_vcpu *vcpu)
return vcpu->arch.apic->pending_events;
  }
 +bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
 +
  #endif
 diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
 index 8664812..0b12b17 100644
 --- a/virt/kvm/ioapic.c
 +++ b/virt/kvm/ioapic.c
 @@ -90,6 +90,47 @@ static unsigned long
>>> ioapic_read_indirect(struct
>>> kvm_ioapic *ioapic,
return result;
  }
 +static void rtc_irq_reset(struct kvm_ioapic *ioapic) +{
 +  ioapic->rtc_status.pending_eoi = 0;
 +  bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS); +}
 + +static void rtc_irq_restore(struct kvm_ioapic *ioapic) +{
 +  struct kvm_vcpu *vcpu; +int vector, i, pending_eoi = 0; 
 +
 +  if (RTC_GSI >= IOAPIC_NUM_PINS) +   return; + + 
 vector =
 ioapic->redirtbl[RTC_GSI].fields.vector;
 +  kvm_for_each_vcpu(i, vcpu, ioapic->kvm) { + if
 (kvm_apic_pending_eoi(vcpu, vector)) { +   
 pending_eoi++;
 +  __set_bit(vcpu->vcpu_id,
> ioapic->rtc_status.dest_map);
>>> You should cleat dest_map at the beginning to get rid of stale bits.
>> I thought kvm_set_ioapic is called only after save/restore or
> migration.
> And
>>> the
> ioapic should be reset successfully before call it. So the
> dest_map is empty before call rtc_irq_restore().
>> But it is possible kvm_set_ioapic is called beside save/restore or
>> migration. Right?
>> 
> First of all userspace should not care when it calls
> kvm_set_ioapic() the kernel need to do the right thing. Second,
> believe it or not, kvm_ioapic_reset() is not called during
> system reset. Instead userspace reset it by calling
> kvm_set_ioapic() with ioapic state after reset.
 Ok. I see. As the logic you suggested, it will clear dest_map if no
 pending eoi in vcpu, so we don't need to do it again.
 
>>> You again rely on userspace doing thing in certain manner. What is
>>> set_lapic() is ne