add new notifier function ,take2

Hi,

A big thanks to everybody who read and replied to first version. I have tried to incorporate reviewer's comments and suggestions.

changelog take1 -> take2

- Rebased 2.6.23
- comment updated
- renamed the notifiner name "tunable_notifier" to "tunable_atomic_notifier"
- fixed typo

These patches add new notifier function and implement it to panic_notifier_list. We used the hardcoded notifier chain so far, but it was not flexible. New notifier is very flexible, because user can change a list of order by debugfs.

Thanks,

Example)

# cd /sys/kernel/debug/
# ls
kprobes  pktcdvd
# insmod ipmi_msghandler.ko
# ls
kprobes  panic_notifier_list  pktcdvd
# cd panic_notifier_list/
# ls
ipmi_msghandler
# insmod ipmi_watchdog.ko
# ls
ipmi_msghandler  ipmi_wdog
# cat ipmi_msghandler/priority
200
# cat ipmi_wdog/priority
150
#
Kernel panic - not syncing: panic
ipmi_msghandler : notifier calls panic_event().
ipmi_watchdog : notifier calls wdog_panic_handler().

.....(reboot)

# cat ipmi_msghandler/priority
200
# cat ipmi_wdog/priority
150
# echo 300 > ipmi_wdog/priority
#
Kernel panic - not syncing: panic
ipmi_watchdog : notifier calls wdog_panic_handler().
ipmi_msghandler : notifier calls panic_event().

--
Takenori Nagano <[email protected]>