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Date: Wed, 18 Jun 2008 12:36:20 +0200
From: Pierangelo Masarati <masarati@domain.hid>
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Subject: Re: [Adeos-main] latency fix for 2.6.25?
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To: rpm@xenomai.org
Cc: adeos-main@gna.org

Philippe Gerum wrote:

>>> Ok, you were talking about the _previous_ implementation, right?
>> Yes.  It's been running for a few hours today, so your fix seems to be 
>> fine; in any case, the tests will run overnight, and I'll let you know 
>> tomorrow.  I believe this issue could not be easily pointed out by just 
>> a simple latency check.
>>
> 
> Agreed, we need to create a load that makes races on seqlocks more likely, and
> ideally with lots of readers delaying a single writer.

The testing of your fix ran overnight without problems, so we'd consider 
it fine.  Another possible fix to preserve linux timings is to use 
local_irq_disable_hw() after halt.  It seems to create no significant 
latency.

Sincerely, p.