| Message ID | 1465318123-3090-3-git-send-email-julien.grall@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 7 Jun 2016, Julien Grall wrote: > The affinity of a guest IRQ is set every time the guest enable it (see > vgic_enable_irqs). > > It is not necessary to set the affinity when the IRQ is routed to the > guest because Xen will never receive the IRQ until it hass been enabled > by the guest. > > Signed-off-by: Julien grall <julien.grall@arm.com> > --- > xen/arch/arm/gic.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c > index 8a1087b..f25381f 100644 > --- a/xen/arch/arm/gic.c > +++ b/xen/arch/arm/gic.c > @@ -97,17 +97,13 @@ void gic_restore_state(struct vcpu *v) > } > > /* > - * needs to be called with a valid cpu_mask, ie each cpu in the mask has > - * already called gic_cpu_init > * - desc.lock must be held > * - arch.type must be valid (i.e != IRQ_TYPE_INVALID) > */ > static void gic_set_irq_properties(struct irq_desc *desc, > - const cpumask_t *cpu_mask, > unsigned int priority) > { > gic_hw_ops->set_irq_properties(desc, priority); > - desc->handler->set_affinity(desc, cpu_mask); > } > > /* Program the GIC to route an interrupt to the host (i.e. Xen) > @@ -123,7 +119,9 @@ void gic_route_irq_to_xen(struct irq_desc *desc, const cpumask_t *cpu_mask, > > desc->handler = gic_hw_ops->gic_host_irq_type; > > - gic_set_irq_properties(desc, cpu_mask, priority); > + desc->handler->set_affinity(desc, cpu_mask); You could call irq_set_affinity here, it might make for nicer code. Actually thinking more about this, I think it would be better to add the irq_set_affinity call to xen/arch/arm/irq.c:setup_irq, right after the call to gic_route_irq_to_xen. That way both gic_route_irq_to_xen and gic_route_irq_to_guest would behave the same way: just setup the routing and not the affinity. What do you think? > + gic_set_irq_properties(desc, priority); > } > > /* Program the GIC to route an interrupt to a guest > @@ -155,7 +153,7 @@ int gic_route_irq_to_guest(struct domain *d, unsigned int virq, > desc->handler = gic_hw_ops->gic_guest_irq_type; > set_bit(_IRQ_GUEST, &desc->status); > > - gic_set_irq_properties(desc, cpumask_of(v_target->processor), priority); > + gic_set_irq_properties(desc, priority); > > p->desc = desc; > res = 0;
Hi Stefano, On 22/06/16 11:54, Stefano Stabellini wrote: > On Tue, 7 Jun 2016, Julien Grall wrote: >> The affinity of a guest IRQ is set every time the guest enable it (see >> vgic_enable_irqs). >> >> It is not necessary to set the affinity when the IRQ is routed to the >> guest because Xen will never receive the IRQ until it hass been enabled >> by the guest. >> >> Signed-off-by: Julien grall <julien.grall@arm.com> >> --- >> xen/arch/arm/gic.c | 10 ++++------ >> 1 file changed, 4 insertions(+), 6 deletions(-) >> >> diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c >> index 8a1087b..f25381f 100644 >> --- a/xen/arch/arm/gic.c >> +++ b/xen/arch/arm/gic.c >> @@ -97,17 +97,13 @@ void gic_restore_state(struct vcpu *v) >> } >> >> /* >> - * needs to be called with a valid cpu_mask, ie each cpu in the mask has >> - * already called gic_cpu_init >> * - desc.lock must be held >> * - arch.type must be valid (i.e != IRQ_TYPE_INVALID) >> */ >> static void gic_set_irq_properties(struct irq_desc *desc, >> - const cpumask_t *cpu_mask, >> unsigned int priority) >> { >> gic_hw_ops->set_irq_properties(desc, priority); >> - desc->handler->set_affinity(desc, cpu_mask); >> } >> >> /* Program the GIC to route an interrupt to the host (i.e. Xen) >> @@ -123,7 +119,9 @@ void gic_route_irq_to_xen(struct irq_desc *desc, const cpumask_t *cpu_mask, >> >> desc->handler = gic_hw_ops->gic_host_irq_type; >> >> - gic_set_irq_properties(desc, cpu_mask, priority); >> + desc->handler->set_affinity(desc, cpu_mask); > > You could call irq_set_affinity here, it might make for nicer code. > > Actually thinking more about this, I think it would be better to add the > irq_set_affinity call to xen/arch/arm/irq.c:setup_irq, right after the > call to gic_route_irq_to_xen. That way both gic_route_irq_to_xen and > gic_route_irq_to_guest would behave the same way: just setup the routing > and not the affinity. > > What do you think? I am fine to call irq_set_affinity from setup_irq. It makes more sense than calling the former from gic_route_irq_to_xen. I will make the change in the next version. Cheers,
diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c index 8a1087b..f25381f 100644 --- a/xen/arch/arm/gic.c +++ b/xen/arch/arm/gic.c @@ -97,17 +97,13 @@ void gic_restore_state(struct vcpu *v) } /* - * needs to be called with a valid cpu_mask, ie each cpu in the mask has - * already called gic_cpu_init * - desc.lock must be held * - arch.type must be valid (i.e != IRQ_TYPE_INVALID) */ static void gic_set_irq_properties(struct irq_desc *desc, - const cpumask_t *cpu_mask, unsigned int priority) { gic_hw_ops->set_irq_properties(desc, priority); - desc->handler->set_affinity(desc, cpu_mask); } /* Program the GIC to route an interrupt to the host (i.e. Xen) @@ -123,7 +119,9 @@ void gic_route_irq_to_xen(struct irq_desc *desc, const cpumask_t *cpu_mask, desc->handler = gic_hw_ops->gic_host_irq_type; - gic_set_irq_properties(desc, cpu_mask, priority); + desc->handler->set_affinity(desc, cpu_mask); + + gic_set_irq_properties(desc, priority); } /* Program the GIC to route an interrupt to a guest @@ -155,7 +153,7 @@ int gic_route_irq_to_guest(struct domain *d, unsigned int virq, desc->handler = gic_hw_ops->gic_guest_irq_type; set_bit(_IRQ_GUEST, &desc->status); - gic_set_irq_properties(desc, cpumask_of(v_target->processor), priority); + gic_set_irq_properties(desc, priority); p->desc = desc; res = 0;
The affinity of a guest IRQ is set every time the guest enable it (see vgic_enable_irqs). It is not necessary to set the affinity when the IRQ is routed to the guest because Xen will never receive the IRQ until it hass been enabled by the guest. Signed-off-by: Julien grall <julien.grall@arm.com> --- xen/arch/arm/gic.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)