Re: [PATCH v5 07/10] hyper-v: globalize vp_index

From: Andy Shevchenko
Date: Tue May 30 2017 - 12:38:20 EST


On Tue, May 30, 2017 at 2:34 PM, Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote:
> To support implementing remote TLB flushing on Hyper-V with a hypercall
> we need to make vp_index available outside of vmbus module. Rename and
> globalize.

> +u32 *hv_vp_index;

> + hv_vp_index[smp_processor_id()] = (u32)msr_vp_index;

Redundant casting.

> + /* Allocate percpu VP index */
> + hv_vp_index = kcalloc(num_possible_cpus(), sizeof(*hv_vp_index),
> + GFP_KERNEL);
> + if (!hv_vp_index)
> + return;

Consider to use kmalloc_array _if_ it doesn't require to be zeroed.

> +static inline int hv_cpu_number_to_vp_number(int cpu_number)
> +{

> + WARN_ON(hv_vp_index[cpu_number] == -1);

How come? u32 will be never negative.

Perhaps you meant == ~0U or U32_MAX

> for_each_cpu_and(cpu, dest, cpu_online_mask)
> - params->vp_mask |= (1ULL << vmbus_cpu_number_to_vp_number(cpu));
> + params->vp_mask |= (1ULL << hv_cpu_number_to_vp_number(cpu));

__set_bit() ?

> for_each_cpu_and(cpu, affinity, cpu_online_mask) {
> int_pkt->int_desc.cpu_mask |=
> - (1ULL << vmbus_cpu_number_to_vp_number(cpu));
> + (1ULL << hv_cpu_number_to_vp_number(cpu));

Ditto.

--
With Best Regards,
Andy Shevchenko