Subject: Re: [RFC PATCH 1/6] netback: page pool version 1

From: Konrad Rzeszutek Wilk <[email-masked]>
Date: Fri, 13 Jan 2012 12:37:46 -0500

> +static idx_t free_head;
> +static int free_count;
> +static unsigned long pool_size;
> +static DEFINE_SPINLOCK(pool_lock);
> +static struct page_pool_entry *pool;
> +
> +static int get_free_entry(void)
> +{
> +	unsigned long flag;
> +	int idx;
> +
> +	spin_lock_irqsave(&pool_lock, flag);

What is the benfit of using the irq version of the spinlock instead
of the normal one??