From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rik van Riel <riel@redhat.com>
Subject: Re: [Patch v2] skbuff: Hide GFP_ATOMIC page allocation failures for
 dropped packets
Date: Tue, 28 May 2013 17:32:07 -0400
Message-ID: <51A52257.4060905@redhat.com>
References: <1369601101-23057-1-git-send-email-atomlin@redhat.com>  <20130527224149.GA4384@electric-eye.fr.zoreil.com>  <51A4D4AD.2010507@candelatech.com>  <20130528161518.GC11614@optiplex.redhat.com> <1369758577.3301.543.camel@edumazet-glaptop>
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Cc: Rafael Aquini <aquini@redhat.com>,
	Ben Greear <greearb@candelatech.com>,
	Francois Romieu <romieu@fr.zoreil.com>, atomlin@redhat.com,
	netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com,
	pshelar@nicira.com, mst@redhat.com, alexander.h.duyck@intel.com,
	sergei.shtylyov@cogentembedded.com, linux-kernel@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <1369758577.3301.543.camel@edumazet-glaptop>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: netdev.vger.kernel.org

On 05/28/2013 12:29 PM, Eric Dumazet wrote:
> On Tue, 2013-05-28 at 13:15 -0300, Rafael Aquini wrote:
>
>> The real problem seems to be that more and more the network stack (drivers, perhaps)
>> is relying on chunks of contiguous page-blocks without a fallback mechanism to
>> order-0 page allocations. When memory gets fragmented, these alloc failures
>> start to pop up more often and they scare ordinary sysadmins out of their paints.
>>
>
> Where do you see that ?
>
> I see exactly the opposite trend.
>
> We have less and less buggy drivers, and we want to catch last
> offenders.

These backtraces would still get printed out for drivers
that DO do the right thing and fall back to smaller
allocations.

The initial failed large allocation would cause a backtrace.