[RFC Part2 v1 03/21] x86, irq: Save destination CPU ID in irq_cfg

Thomas Gleixner
2014-09-16T17:47:27Z

On Thu, 11 Sep 2014, Jiang Liu wrote:

> Cache destination CPU APIC ID into struct irq_cfg when assigning vector
> for interrupt. Upper layer just needs to read the cached APIC ID instead
> of calling apic->cpu_mask_to_apicid_and(), it helps to hide APIC driver
> details from IOAPIC/HPET/MSI drivers..
>
> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
> ---
> arch/x86/include/asm/hw_irq.h | 1 +
> arch/x86/kernel/apic/vector.c | 4 ++++
> 2 files changed, 5 insertions(+)
>
> diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
> index 7624fffc2822..3d51d74d6c01 100644
> --- a/arch/x86/include/asm/hw_irq.h
> +++ b/arch/x86/include/asm/hw_irq.h
> @@ -116,6 +116,7 @@ struct irq_data;
> struct irq_cfg {
> cpumask_var_t domain;
> cpumask_var_t old_domain;
> + unsigned int dest_apicid;
> u8 vector;
> u8 move_in_progress : 1;
> #ifdef CONFIG_IRQ_REMAP
> diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
> index 7562cb15b3bd..287ae4e8d500 100644
> --- a/arch/x86/kernel/apic/vector.c
> +++ b/arch/x86/kernel/apic/vector.c
> @@ -188,6 +188,10 @@ next:
> }
> free_cpumask_var(tmp_mask);

Lacks a comment what this call is actually doing.

> + if (!err)
> + err = apic->cpu_mask_to_apicid_and(mask, cfg->domain,
> + &cfg->dest_apicid);
> +

Thanks,

tglx