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Subject: Re: [UBUNTU:acpi/ec] Use semaphore instead of spinlock
From: Arjan van de Ven <arjan@infradead.org>
To: Randy Dunlap <randy.dunlap@oracle.com>
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Date: Thu, 15 Jun 2006 17:40:59 +0200
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On Wed, 2006-06-14 at 18:14 -0700, Randy Dunlap wrote:
> updated version:
> 
> From: Ben Collins <bcollins@ubuntu.com>
> 
> [UBUNTU:acpi/ec] Use semaphore instead of spinlock to get rid of missed
> interrupts on ACPI EC (embedded controller)


that is odd.

first of all this should use a mutex not a semaphore.

Second, if this isn't used in irq context, then just dropping the
"_irqsave" from the spinlocks should be enough to actually get rid of
the missed interrupts.... and if it is used there then I highly question
your use of semaphores etc...