[PATCH V3] ARM: KVM: Allow host virtual timer irq number to be different from guest virtual timer irq number
Marc Zyngier
marc.zyngier at arm.com
Fri Apr 26 09:47:12 EDT 2013
On 26/04/13 14:27, Anup Patel wrote:
> The arch_timer irq numbers (or PPI number) are implementation dependent so, the host virtual timer irq number can be different from guest virtual timer irq number.
>
> This patch ensures that host virtual timer irq number is read from DTB and guest virtual timer irq is determined based on guest vcpu target type.
>
> Signed-off-by: Anup Patel <anup.patel at linaro.org>
> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar at linaro.org>
> ---
> arch/arm/include/asm/kvm_arch_timer.h | 7 +++++++
> arch/arm/include/asm/kvm_host.h | 1 +
> arch/arm/kvm/arch_timer.c | 32 +++++++++++++++++++++++++-------
> arch/arm/kvm/guest.c | 15 +++++++++++++++
> arch/arm/kvm/reset.c | 4 +++-
> 5 files changed, 51 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm/include/asm/kvm_arch_timer.h b/arch/arm/include/asm/kvm_arch_timer.h
> index 68cb9e1..c5c135b 100644
> --- a/arch/arm/include/asm/kvm_arch_timer.h
> +++ b/arch/arm/include/asm/kvm_arch_timer.h
> @@ -61,6 +61,7 @@ struct arch_timer_cpu {
> #ifdef CONFIG_KVM_ARM_TIMER
> int kvm_timer_hyp_init(void);
> int kvm_timer_init(struct kvm *kvm);
> +int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu);
> void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu);
> void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu);
> void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu);
> @@ -76,7 +77,13 @@ static inline int kvm_timer_init(struct kvm *kvm)
> return 0;
> }
>
> +static int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
> +{
> + return 0;
> +}
> +
> static inline void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) {}
> +
> static inline void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) {}
> static inline void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) {}
> static inline void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) {}
> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
> index 57cb786..cdc0551 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -43,6 +43,7 @@
> struct kvm_vcpu;
> u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode);
> int kvm_target_cpu(void);
> +struct kvm_irq_level *kvm_target_timer_irq(struct kvm_vcpu *vcpu);
> int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
> void kvm_reset_coprocs(struct kvm_vcpu *vcpu);
>
> diff --git a/arch/arm/kvm/arch_timer.c b/arch/arm/kvm/arch_timer.c
> index 49a7516..e558115 100644
> --- a/arch/arm/kvm/arch_timer.c
> +++ b/arch/arm/kvm/arch_timer.c
> @@ -30,7 +30,7 @@
>
> static struct timecounter *timecounter;
> static struct workqueue_struct *wqueue;
> -static struct kvm_irq_level timer_irq = {
> +static struct kvm_irq_level host_timer_irq = {
> .level = 1,
> };
>
> @@ -67,8 +67,8 @@ static void kvm_timer_inject_irq(struct kvm_vcpu *vcpu)
>
> timer->cntv_ctl |= ARCH_TIMER_CTRL_IT_MASK;
> kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
> - vcpu->arch.timer_cpu.irq->irq,
> - vcpu->arch.timer_cpu.irq->level);
> + timer->irq->irq,
> + timer->irq->level);
> }
>
> static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
> @@ -156,6 +156,24 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
> timer_arm(timer, ns);
> }
>
> +int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
If you change this function to:
int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, struct kvm_irq_level *irq)
...
> +{
> + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
> +
> + /*
> + * The vcpu timer irq number cannot be determined in
> + * kvm_timer_vcpu_init() because it is called much before
> + * kvm_vcpu_set_target(). To handle this, we determine
> + * vcpu timer irq number when the vcpu is resetted.
> + */
> + timer->irq = kvm_target_timer_irq(vcpu);
> + if (!timer->irq) {
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
> {
> struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
> @@ -163,12 +181,12 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
> INIT_WORK(&timer->expired, kvm_timer_inject_irq_work);
> hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
> timer->timer.function = kvm_timer_expire;
> - timer->irq = &timer_irq;
> + timer->irq = NULL;
> }
>
> static void kvm_timer_init_interrupt(void *info)
> {
> - enable_percpu_irq(timer_irq.irq, 0);
> + enable_percpu_irq(host_timer_irq.irq, 0);
> }
>
>
> @@ -182,7 +200,7 @@ static int kvm_timer_cpu_notify(struct notifier_block *self,
> break;
> case CPU_DYING:
> case CPU_DYING_FROZEN:
> - disable_percpu_irq(timer_irq.irq);
> + disable_percpu_irq(host_timer_irq.irq);
> break;
> }
>
> @@ -230,7 +248,7 @@ int kvm_timer_hyp_init(void)
> goto out;
> }
>
> - timer_irq.irq = ppi;
> + host_timer_irq.irq = ppi;
>
> err = register_cpu_notifier(&kvm_timer_cpu_nb);
> if (err) {
> diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
> index 152d036..6fbc988 100644
> --- a/arch/arm/kvm/guest.c
> +++ b/arch/arm/kvm/guest.c
> @@ -36,6 +36,11 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
> { NULL }
> };
>
> +static struct kvm_irq_level target_cortex_a15_timer_irq = {
> + .irq = 27,
> + .level = 1,
> +};
... Move this to reset.c ...
> int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
> {
> return 0;
> @@ -197,6 +202,16 @@ int __attribute_const__ kvm_target_cpu(void)
> }
> }
>
> +struct kvm_irq_level *kvm_target_timer_irq(struct kvm_vcpu *vcpu)
> +{
> + switch (vcpu->arch.target) {
> + case KVM_ARM_TARGET_CORTEX_A15:
> + return &target_cortex_a15_timer_irq;
> + default:
> + return NULL;
> + };
> +}
... drop this ...
> int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
> const struct kvm_vcpu_init *init)
> {
> diff --git a/arch/arm/kvm/reset.c b/arch/arm/kvm/reset.c
> index b80256b..655e567 100644
> --- a/arch/arm/kvm/reset.c
> +++ b/arch/arm/kvm/reset.c
> @@ -26,6 +26,7 @@
> #include <asm/cputype.h>
> #include <asm/kvm_arm.h>
> #include <asm/kvm_coproc.h>
> +#include <asm/kvm_arch_timer.h>
>
> /******************************************************************************
> * Cortex-A15 Reset Values
> @@ -70,5 +71,6 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
...
In case KVM_ARM_TARGET_CORTEX_A15:
[...]
timer_irq = &target_cortex_a15_timer_irq;
...
> /* Reset CP15 registers */
> kvm_reset_coprocs(vcpu);
>
> - return 0;
> + /* Reset arch_timer context */
> + return kvm_timer_vcpu_reset(vcpu);
... and call kvm_timer_vcpu_reset(vcpu, timer_irq)
it would look much better.
M.
--
Jazz is not dead. It just smells funny...
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