From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm@xmission.com (Eric W. Biederman)
Subject: Re: [RFC PATCH 2/2] netpoll: Don't poll for received packets
Date: Thu, 13 Mar 2014 13:48:29 -0700
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Cc: Eric Dumazet <eric.dumazet@gmail.com>,
	David Miller <davem@davemloft.net>,
	Linux Kernel Network Developers <netdev@vger.kernel.org>,
	Matt Mackall <mpm@selenic.com>,
	Satyam Sharma <satyam.sharma@gmail.com>
To: Cong Wang <xiyou.wangcong@gmail.com>
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In-Reply-To: <CAM_iQpVRkHR7_coMDUSLkVmhAgbO==b4BVPuKTMpKz+SRz=WjA@mail.gmail.com>
	(Cong Wang's message of "Wed, 12 Mar 2014 11:39:49 -0700")
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Cong Wang <xiyou.wangcong@gmail.com> writes:

> On Tue, Mar 11, 2014 at 1:45 AM, Eric W. Biederman
> <ebiederm@xmission.com> wrote:
>> -       work = napi->poll(napi, budget);
>> -       trace_napi_poll(napi);
>> +       /* Use a budget of 0 to request the drivers not process
>> +        * their receive queue.  Warn when they do anyway.
>> +        */
>> +       work = napi->poll(napi, 0);
>> +       WARN_ON_ONCE(work != 0);
>>
>
> Adding more printk's in netpoll call path would only bring more
> troubles.

That is why I used WARN_ON_ONCE.  So we are alerted to problems but
because it only prints once service won't be denied if nothing except
that warning cares.

Eric