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Date: Fri, 19 Jan 2018 13:47:27 -0500 (EST)
Message-Id: <20180119.134727.512994648781037639.davem@davemloft.net>
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Subject: Re: [RFC PATCH 1/4] softirq: Limit vector to a single iteration on
 IRQ tail
From: David Miller <davem@davemloft.net>
In-Reply-To: <CA+55aFwtnAqbz=WNuO4oAo=wwQ+Vm+wApqof9h-waOcCrZgCEA@mail.gmail.com>
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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 19 Jan 2018 10:25:03 -0800

> On Fri, Jan 19, 2018 at 8:16 AM, David Miller <davem@davemloft.net> wrote:
>>
>> So this "get requeued" condition I think will trigger always for
>> networking tunnel decapsulation.
> 
> Hmm. Interesting and a perhaps bit discouraging.
> 
> Will it always be just a _single_ level of indirection, or will double
> tunnels (I assume some people do that, just because the universe is
> out to get us) then result in this perhaps repeating several times?

Every level of tunnel encapsulation will trigger a new softirq.

So if you have an IP tunnel inside of an IP tunnel that will trigger
twice.