Priorities of IRQ handlers

[John Sigler <linux.kernel@free.fr>]

Hello everyone,

I'm running 2.6.22.1-rt9 on x86.

CONFIG_PREEMPT_RT=y
CONFIG_PREEMPT=y
CONFIG_PREEMPT_SOFTIRQS=y
CONFIG_PREEMPT_HARDIRQS=y
CONFIG_PREEMPT_BKL=y
# CONFIG_CLASSIC_RCU is not set
CONFIG_PREEMPT_RCU=y

I need to change the priorities of several soft and hard IRQ handlers.

Namely,

o reduce the prio of "softirq-timer" handler to 10

o reduce the prio of IRQ14 and IRQ15 handlers to 20
   (my flash drives do not support DMA BTW...)

o boost the prio of my I/O boards' IRQ handlers to 60
   (there can be 1 or 2 boards, the driver is a kernel module
    which is loaded after the system has booted.)

I've written a short program that calls
   sched_setscheduler(pid, SCHED_FIFO, &param);
with the appropriate pid, which I look up using ps -ef

I need to automate the process of tweaking priorities.

Can someone offer advice and / or pointers?

Regards.