Re: [PATCH v2 03/45] notifier: Add atomic/blocking_notifier_has_unique_priority()

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

On Thu, Oct 28, 2021 at 12:16:33AM +0300, Dmitry Osipenko wrote:
> Add atomic/blocking_notifier_has_unique_priority() helpers which return
> true if given handler has unique priority.

...

> +/**
> + *   atomic_notifier_has_unique_priority - Checks whether notifier's 
> priority is unique
> + *   @nh: Pointer to head of the atomic notifier chain
> + *   @n: Entry in notifier chain to check
> + *
> + *   Checks whether there is another notifier in the chain with the same 
> priority.
> + *   Must be called in process context.
> + *
> + *   Returns true if priority is unique, false otherwise.

Why this indentation?

> + */
> +bool atomic_notifier_has_unique_priority(struct atomic_notifier_head *nh,
> +             struct notifier_block *n)
> +{
> +     struct notifier_block **nl = &nh->head;
> +     unsigned long flags;
> +     bool ret = true;
> +
> +     spin_lock_irqsave(&nh->lock, flags);
> +
> +     while ((*nl) != NULL && (*nl)->priority >= n->priority) {

' != NULL' is redundant.

> +             if ((*nl)->priority == n->priority && (*nl) != n) {
> +                     ret = false;
> +                     break;
> +             }
> +
> +             nl = &((*nl)->next);
> +     }
> +
> +     spin_unlock_irqrestore(&nh->lock, flags);
> +
> +     return ret;
> +}

...

> +     /*
> +      * This code gets used during boot-up, when task switching is
> +      * not yet working and interrupts must remain disabled.  At

One space is enough.

> +      * such times we must not call down_write().
> +      */

> +     while ((*nl) != NULL && (*nl)->priority >= n->priority) {

' != NULL' is not needed.

> +             if ((*nl)->priority == n->priority && (*nl) != n) {
> +                     ret = false;
> +                     break;
> +             }
> +
> +             nl = &((*nl)->next);
> +     }

-- 
With Best Regards,
Andy Shevchenko