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Date: Tue, 17 Jun 2014 11:38:44 +0900
From: Jongsung Kim <neidhard.kim@lge.com>
Organization: LG Electronics
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CC: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
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        Youngkyu Choi <youngkyu7.choi@lge.com>
Subject: Re: [PATCH] net/cadence/macb: clear interrupts simply and correctly
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On 06/16/2014 11:56 PM, Sören Brinkmann wrote:
> On Mon, 2014-06-16 at 02:00PM +0900, Jongsung Kim wrote:
>> On 06/13/2014 12:44 AM, Sören Brinkmann wrote:
>>> This is now clearing all IRQ flags which is probably not what we want
>>> here. This is handling RX only. We still want the non-RX interrupts to go to
>>> the actual interrupt service routing.
>>
>> The ISR(Interrupt Status Register) is read only in the interrupt service
>> routine, macb_interrupt. But is partially cleared here and there. Further
>> handler-functions decide jobs to be done by reading/checking other status
>> registers. (e.g., TSR, RSR) So, clearing the ISR after reading looks not
>> a bad idea.
>
> But you are clearing _all_ interrupt flags in the RX NAPI handler.
> Doesn't that mean we might miss certain events?

Please inspect my patch again. What I did in the macb_poll is removing
statements clearing the Rx-complete interrupt, not clearing all the
interrupts.