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Date: Sun, 06 Apr 2008 14:46:06 -0600
From: Robert Hancock <hancockr@shaw.ca>
Subject: Re: Hooking to APIC timer on SMP 32-bit X86 system
In-reply-to: <fa.ORNHzXNKWJTtCts8OxkQgfojzSk@ifi.uio.no>
To: YM Yen <yminyen@gmail.com>
Cc: linux-kernel@vger.kernel.org
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YM Yen wrote:
> hi,
> 
> I am looking for a way to program the APIC timer in a kernel module so 
> that the module depends only on the hardware timer instead of the timer 
> provided by the kernel. Programming the LVT is easy, however I can't 
> find a way to have the Linux kernel to call my interrupt service routine 
> in addition to smp_apic_timer_interrupt().
> 
> Is doing this even possible? There doesn't seem to be any sort of hook 
> or notifier chain I can install a ISR to. Thanks in advance.

It might be possible, but likely not easy and not recommended. Why is a 
kernel timer not sufficient for what you need?