Re: [PATCH v5 3/3] irqchip/loongson-eiointc: Add extioi virt extension support
From: Thomas Gleixner
Date: Sat Aug 10 2024 - 16:46:53 EST
On Mon, Aug 05 2024 at 15:35, Bibo Mao wrote:
> Interrupts can be routed to maximal four virtual CPUs with one external
> hardware interrupt. Add the extioi virt extension support so that
> Interrupts can be routed to 256 vcpus on hypervisor mode.
interrupts .... 256 vCPUs in hypervisor mode.
> static int cpu_to_eio_node(int cpu)
> {
> - return cpu_logical_map(cpu) / CORES_PER_EIO_NODE;
> + int cores;
> +
> + if (kvm_para_available() && kvm_para_has_feature(KVM_FEATURE_VIRT_EXTIOI))
Why isn't that kvm_para_available() check inside of
kvm_para_has_feature() instead of inflicting it on every usage site?
That's just error prone.
> + cores = CORES_PER_VEIO_NODE;
> + else
> + cores = CORES_PER_EIO_NODE;
> + return cpu_logical_map(cpu) / cores;
> }
> @@ -105,18 +144,24 @@ static int eiointc_set_irq_affinity(struct irq_data *d, const struct cpumask *af
> @@ -140,17 +185,23 @@ static int eiointc_index(int node)
>
> static int eiointc_router_init(unsigned int cpu)
> {
> - int i, bit;
> - uint32_t data;
> - uint32_t node = cpu_to_eio_node(cpu);
> - int index = eiointc_index(node);
> + uint32_t data, node;
> + int i, bit, cores, index;
Is it so hard to follow:
https://www.kernel.org/doc/html/latest/process/maintainer-tip.html#variable-declarations
?
Thanks,
tglx