From mboxrd@z Thu Jan  1 00:00:00 1970
From: Martin Shepherd <mcs@astro.caltech.edu>
Subject: Re: Setting the priority of an IRQ thread
Date: Tue, 16 Jun 2009 07:59:28 +0000 (UTC)
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References: <loom.20090615T222836-377@post.gmane.org> <000001c9ee36$218cf3a0$a852c70a@dlh.st.com>
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Suresh Kumar SHUKLA <suresh.shukla <at> st.com> writes:
> 	// get IRQ descriptor from IRQ, it contains pid
> 	desc = &irq_desc[IRQ_BASIC_TIMER_3_1];

That's a very useful clue. I was thinking that I would have to walk the process
tree to find the thread by name. Following up on this clue, it appears as though
in kernel 2.6.29.4 I should be able to use desc=irq_to_desc(irq) to look up the
IRQ descriptor, then use pid=get_task_pid(desc->thread), to get the PID of the
IRQ thread, then use sys_sched_setscheduler(pid,...) to change its priority.
I'll try that out in the morning.

Thanks for the reply,

Martin