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From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net] ixgbe: check return value of napi_complete_done()
Date: Thu, 20 Sep 2018 16:49:06 -0700
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Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
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To: Song Liu <songliubraving@fb.com>,
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On 09/20/2018 04:43 PM, Song Liu wrote:
> 

> I tried to totally skip ndo_poll_controller() here. It did avoid hitting
> the issue. However, netpoll will drop (fail to send) more packets. 
>

Why is it failing ?

If you are under high memory pressure, then maybe if you absolutely want memory to send
netpoll packets, you want to grab all NAPI contexts as a way to prevent other cpus 
from feeding incoming packets to the host and add more memory pressure ;)