Re: [PATCH] x86/hyper-v: Stop caring about EOI for direct stimers
On 05/12/18 16:36, 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
> Signed-off-by: Vitaly Kuznetsov
> ---
> 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;
> }
>
Queued, thanks.
Paolo
Re: [PATCH] x86/hyper-v: Stop caring about EOI for direct stimers
Roman Kagan writes:
> [ 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
>> Signed-off-by: Vitaly Kuznetsov
>> ---
>> 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.
I'm fine either way, I'm going to send v2 with a new patch adding the
check to stimer_set_config() and leave it up to Paolo if he would want
to squash them all together before sending to Linus.
Re: [PATCH] x86/hyper-v: Stop caring about EOI for direct stimers
[ 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
> Signed-off-by: Vitaly Kuznetsov
> ---
> 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.
