Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and OOM

From	David Miller <davem@davemloft.net>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and OOM
Date	2017-01-18 22:30 +0100
Message-ID	<t15XR-Vm-41@gated-at.bofh.it> (permalink)
References	<t08XM-4M7-15@gated-at.bofh.it> <t08XM-4M7-13@gated-at.bofh.it> <t123T-6Si-15@gated-at.bofh.it>
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From: Vineeth Remanan Pillai <vineethp@amazon.com>
Date: Wed, 18 Jan 2017 09:02:17 -0800

> 
> On 01/15/2017 10:24 PM, Juergen Gross wrote:
>> On 13/01/17 18:55, Remanan Pillai wrote:
>>> From: Vineeth Remanan Pillai <vineethp@amazon.com>
>>>
>>> During an OOM scenario, request slots could not be created as skb
>>> allocation fails. So the netback cannot pass in packets and netfront
>>> wrongly assumes that there is no more work to be done and it disables
>>> polling. This causes Rx to stall.
>>>
>>> The issue is with the retry logic which schedules the timer if the
>>> created slots are less than NET_RX_SLOTS_MIN. The count of new request
>>> slots to be pushed are calculated as a difference between new req_prod
>>> and rsp_cons which could be more than the actual slots, if there are
>>> unconsumed responses.
>>>
>>> The fix is to calculate the count of newly created slots as the
>>> difference between new req_prod and old req_prod.
>>>
>>> Signed-off-by: Vineeth Remanan Pillai <vineethp@amazon.com>
>> Reviewed-by: Juergen Gross <jgross@suse.com>
> Thanks Juergen.
> 
> David,
> 
> Could you please pick up this change for net-next if there no more
> concerns..

Why would I pick up "this change", if the author of the patch has
stated that he will resubmit the change implemented differently based
upon my feedback?

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Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and  OOM Vineeth Remanan Pillai <vineethp@amazon.com> - 2017-01-18 18:20 +0100
  Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress  and OOM David Miller <davem@davemloft.net> - 2017-01-18 21:30 +0100
    Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and  OOM Vineeth Remanan Pillai <vineethp@amazon.com> - 2017-01-18 21:40 +0100
  Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress  and OOM David Miller <davem@davemloft.net> - 2017-01-18 22:30 +0100

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