From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net: Update netdev_alloc_frag to work more efficiently
 with TCP and GRO
Date: Thu, 21 Jun 2012 07:07:06 +0200
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Cc: Alexander Duyck <alexander.h.duyck@intel.com>,
	netdev@vger.kernel.org, davem@davemloft.net,
	jeffrey.t.kirsher@intel.com
To: Alexander Duyck <alexander.duyck@gmail.com>
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On Wed, 2012-06-20 at 21:07 -0700, Alexander Duyck wrote:
> On 6/20/2012 6:21 AM, Eric Dumazet wrote:

> > +		nc->page = alloc_pages(GFP_ATOMIC | __GFP_COLD |
> > +				       (NETDEV_FRAG_ORDER ? __GFP_COMP : 0),
> > +				       NETDEV_FRAG_ORDER);

> I was wondering if you needed the check for NETDEV_FRAG_ORDER here.  
>  From what I can tell setting __GFP_COMP for an order 0 page has no 
> effect since it only seems to get checked in prep_new_page and that is 
> after a check to verify if the page is order 0 or not.

Good point, it seems some net drivers could be changed to remove
useless tests.

I'll post some performance data as well.