From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <wei.liu2@citrix.com>
Subject: Re: [RFC PATCH 1/6] netback: page pool version 1
Date: Mon, 16 Jan 2012 09:31:12 +0000
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To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: wei.liu2@citrix.com, Ian Campbell <Ian.Campbell@citrix.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, "netdev@vger.kernel.org" <netdev@vger.kernel.org>
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On Fri, 2012-01-13 at 17:37 +0000, Konrad Rzeszutek Wilk wrote:
> > +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??
> 

This should be vestige of iterations, fixed.

Thanks
Wei.