Message-ID: <4C1F6E8E.6050301@kernel.org>
Date: Mon, 21 Jun 2010 15:52:14 +0200
From: Tejun Heo <tj@kernel.org>
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To: jeff@garzik.org
CC: mingo@elte.hu, tglx@linutronix.de, bphilips@suse.de, yinghai@kernel.org,
       akpm@linux-foundation.org, torvalds@linux-foundation.org,
       linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org,
       stern@rowland.harvard.edu, gregkh@suse.de, khali@linux-fr.org
Subject: Re: [PATCH 11/12] libata: use IRQ expecting
References: <1276443098-20653-1-git-send-email-tj@kernel.org> <1276443098-20653-12-git-send-email-tj@kernel.org>
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On 06/13/2010 05:31 PM, Tejun Heo wrote:
> Thanks to its age, ATA is very susceptible to IRQ delivery problems in
> both directions - lost and spurious interrupts.  In traditional PATA,
> the IRQ line is ultimately out of the controller and driver's control.
> Even relatively new SATA isn't free from these issues.  Many
> controllers still emulate the traditional IDE interface which doesn't
> have reliable way to indicate interrupt pending state and there also
> is an issue regarding the interpretation of nIEN on both sides of the
> cable.
> 
> Most of these problems can be worked around by using the new IRQ
> expecting mechanism without adding noticeable overhead.  In ATA,
> almost all operations are initiated by the host and the controller
> signals progress or completion using IRQ.  IRQ expecting can easily be
> added in libata core and applied to all libata drivers.
> 
> Signed-off-by: Tejun Heo <tj@kernel.org>

Jeff, can you please ack this change if this looks okay to you?  Also,
would it okay to route this through irq tree?

Thanks.

-- 
tejun
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