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Date: Tue, 7 Sep 2010 15:38:13 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Anton Vorontsov <avorontsov@mvista.com>
Subject: Re: [PATCH 0/8] sdhci: Move real work out of an atomic context
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Cc: Matt Fleming <matt@console-pimps.org>,
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On Wed, 14 Jul 2010 17:07:28 +0400
Anton Vorontsov <avorontsov@mvista.com> wrote:

> Hi all,
> 
> Currently the sdhci driver does everything in the atomic context.
> And what is worse, PIO transfers are made from the IRQ handler.
> 
> This causes huge latencies (up to 120 ms). On some P2020 SOCs,
> DMA and card detection is broken, which means that kernel polls
> for the card via PIO transfers every second. Needless to say
> that this is quite bad.
> 
> So, this patch set reworks sdhci code to avoid atomic context,
> almost completely. We only do two device memory operations
> in the atomic context, and all the rest is threaded.
> 
> I noticed no throughput drop neither with PIO transfers nor
> with DMA (tested on MPC8569E CPU), while latencies should be
> greatly improved.
> 

This patchset isn't causing any problems yet, but may do so in the
future and will impact the validity of any testing.  It seems to be
kind of stuck.  Should I drop it all?