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From: Jeff Angielski <jeff@theptrgroup.com>
To: Rune Torgersen <runet@innovsys.com>
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Date: Tue, 20 Sep 2005 14:40:16 -0400
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Cc: linuxppc-embedded@ozlabs.org
Subject: Re: wait_event and interrupts
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On Tue, 2005-09-20 at 12:56 -0500, Rune Torgersen wrote:

> Is there a better way of doing this?

If you *must* share the variable between interrupt and non-interrupt
context, you must mutex it in an interrupt safe way.  The use of
spin_lock_irqsave() comes to mind for you read function.

But you are going to have other problems with this approach anyways
since you "appear" to be assuming a one-to-one relationship between your
interrupt handler and the read function.  Is that really true?

Jeff Angielski
The PTR Group