Re: [PATCH] usb: gadget: u_ether: remove interrupt throttling

[Felipe Balbi <felipe.balbi@linux.intel.com>]

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Hi,

David Miller <davem@davemloft.net> writes:
> From: Felipe Balbi <felipe.balbi@linux.intel.com>
> Date: Thu, 03 Nov 2016 09:04:54 +0200
>
>> What Dave Miller is saying is that it's ALWAYS a bug to delay
>> completion of SKBs. The only thing you're doing with chipidea is
>> delaying interrupt by up to 125us; which is still a bug from the
>> point of view of the networking layer, but it's more difficult to
>> perceive any problems because of the short time where interrupt is
>> delayed.
>
> I didn't say delaying was illegal.
>
> I said that the SKB free must occur in a reasonable, finite, amount of
> time.

"reasonable" is rather subjective. Completions are, of course,
finite. It just means that once a transfer completes *and* has interrupt
enabled, then several other SKBs will be completed along with it.

That doesn't mean *all* SKBs completed at the same time, it means once
we get an interrupt, we give back all previous ones, but we don't know
exactly when they completed.

-- 
balbi

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