From: Grant Edwards <grant.b.edwards@gmail.com>
To: linux-rt-users@vger.kernel.org
Subject: Re: Using patch-2.6.33.7.2-rt30 increases latency and CPU usage?
Date: Fri, 11 May 2012 13:56:22 +0000 (UTC) [thread overview]
Message-ID: <joj5q6$e3h$1@dough.gmane.org> (raw)
In-Reply-To: CANqCtQ+HbGMUqJuZN-weX1CbK9ecTgfdenV4WgZiDQQ_ZAYSUA@mail.gmail.com
On 2012-05-11, Remy Bohmer <linux@bohmer.net> wrote:
> Hi,
>
> 2012/5/10 Grant Edwards <grant.b.edwards@gmail.com>:
>>> If the 20usec requirement is hard, you can also look at using an FIQ.
>>
>> Does the normal AT91 kernel not use FIQs at all? ?If so, I might be
>> able to dedicate the FIQ to this function and have it happen without
>> the Linux kernel knowing about it (or affecting it). ?Any
>> communication between it and a normal user-task would have to be
>> handled carefully...
>
> No, the kernel does not use the FIQ at all. It is free for you to use
> as you want. Communication with the FIQ handler can be done using a
> queue based on atomic instructions.
Thanks! I was about to start looking into that...
--
Grant Edwards grant.b.edwards Yow! I just forgot my whole
at philosophy of life!!!
gmail.com
next prev parent reply other threads:[~2012-05-11 13:56 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-09 21:18 Using patch-2.6.33.7.2-rt30 increases latency and CPU usage? Grant Edwards
2012-05-09 22:00 ` Grant Edwards
2012-05-09 22:13 ` Joachim Achtzehnter
2012-05-09 23:18 ` Grant Edwards
2012-05-10 9:46 ` Remy Bohmer
2012-05-10 13:53 ` Grant Edwards
2012-05-11 13:42 ` Remy Bohmer
2012-05-11 13:56 ` Grant Edwards [this message]
2012-05-11 18:46 ` Tim Sander
2012-05-15 17:33 ` Steven Rostedt
2012-05-15 22:58 ` Grant Edwards
2012-05-15 23:06 ` Steven Rostedt
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