From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC PATCH] mlx5: Fix page rfcnt issue
Date: Mon, 23 Jan 2017 19:16:53 -0500 (EST)
Message-ID: <20170123.191653.947869807938526572.davem@davemloft.net>
References: <20170123235658.3872770-1-tom@herbertland.com>
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From: Tom Herbert <tom@herbertland.com>
Date: Mon, 23 Jan 2017 15:56:58 -0800

> One other potential problem in the driver is the use of put_page in
> release pages.  Comparing how the allocation is done in other drivers
> (for instance comparing to ixgbe) some seem to use __free_pages instead.
> I don't know which is correct to use, but somehow it doesn't seem like
> they can both be right.

The only difference I can see is that put_page() does a
__page_cache_release() which shouldn't be necessary for driver RX
pages, so it could be unnecessary overhead.