Re: [PATCH 4/7] xen/events: remove some simple helpers from events_base.c

[Oleksandr Tyshchenko <Oleksandr_Tyshchenko@xxxxxxxx>]

On 16.10.23 09:28, Juergen Gross wrote:


Hello Juergen.


> The helper functions type_from_irq() and cpu_from_irq() are just one
> line functions used only internally.
> 
> Open code them where needed. At the same time modify and rename
> get_evtchn_to_irq() to return a struct irq_info instead of the IRQ
> number.
> 
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>



[snip]



> 
> @@ -1181,15 +1172,16 @@ static int bind_evtchn_to_irq_chip(evtchn_port_t 
> evtchn, struct irq_chip *chip,
>   {
>       int irq;
>       int ret;
> +     struct irq_info *info;
>   
>       if (evtchn >= xen_evtchn_max_channels())
>               return -ENOMEM;


I assume this check is called here (*before* holding a lock) by 
intention, as evtchn_to_info() below contains the same check.

>   
>       mutex_lock(&irq_mapping_update_lock);
>   
> -     irq = get_evtchn_to_irq(evtchn);
> +     info = evtchn_to_info(evtchn) >
> -     if (irq == -1) {
> +     if (!info) {
>               irq = xen_allocate_irq_dynamic();
>               if (irq < 0)
>                       goto out;
> @@ -1212,8 +1204,8 @@ static int bind_evtchn_to_irq_chip(evtchn_port_t 
> evtchn, struct irq_chip *chip,
>                */
>               bind_evtchn_to_cpu(evtchn, 0, false);
>       } else {
> -             struct irq_info *info = info_for_irq(irq);
> -             WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
> +             WARN_ON(info->type != IRQT_EVTCHN);
> +             irq = info->irq;
>       }


This hunk doesn't apply clearly to the latest state, because of 
"9e90e58c11b7 xen: evtchn: Allow shared registration of IRQ handers" 
went in. Please rebase.


With that:
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>


Also checkpatch.pl warns about BUG_ON usage in several places, but again 
you didn't introduce them in current patch, just touched their args.


[snip]