Debugging Linux Kernel Using SystemTap Part-9 - Probing interrupts

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In Linux, do_IRQ() function is called on each interrupt, which calls handle_IRQ_event(), which finally calls the handlers registered with request_irq() call.

Systemtap already provides scripts/tapset for irq (/usr/local/share/systemtap/tapset/linux/irq.stp)

Script:
probe irq_handler.entry, irq_handler.exit {
printf("%s:%-16s %s irq %d dev %s\n",ctime(gettimeofday_s()), pn(), symname(handler),
irq, kernel_string(dev_name))
}
view raw irq.stp hosted with ❤ by GitHub

Output:


Notes:

 1. symname function will print out the raw address
2. kernel_string will get the string at the address passed as argument
3. pn() returns the active probe name

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