From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [net-next.git 4/7] stmmac: add Rx watchdog optimization to
 mitigate the DMA irqs
Date: Wed, 05 Sep 2012 13:16:15 -0400 (EDT)
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From: Ben Hutchings <bhutchings@solarflare.com>
Date: Wed, 5 Sep 2012 17:14:35 +0100

> On Wed, 2012-09-05 at 17:03 +0200, Giuseppe CAVALLARO wrote:
>> GMAC devices newer than databook 3.50 has an embedded timer
>> that can be used for mitigating the number of interrupts.
>> So this patch adds this optimizations.
>> Old MAC will continue to use NAPI.
> [...]
> 
> Interrupt moderation is *not* a substitute for NAPI; you should continue
> using NAPI as well.

Absolutely correct, these two facilities are _complementary_ not _exlusive_.

In fact, the most optimal driver will use NAPI with relatively short HW
mitigation settings.