On 19/08/2022 19:17, Guilherme G. Piccoli wrote:

Currently there is no way to show the callback names for registered,
unregistered or executed notifiers. This is very useful for debug
purposes, hence add this functionality here in the form of notifiers'
tracepoints, one per operation.

Cc: Arjan van de Ven <redacted>
Cc: Cong Wang <redacted>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <redacted>
Cc: Xiaoming Ni <redacted>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>

---

V3:
- Yet another major change - thanks to Arjan's great suggestion,
refactored the code to make use of tracepoints instead of guarding
the output with a Kconfig debug setting.

V2:
- Major improvement thanks to the great idea from Xiaoming - changed
all the ksym wheel reinvention to printk %ps modifier;

- Instead of ifdefs, using IS_ENABLED() - thanks Steven.

- Removed an unlikely() hint on debug path.


 include/trace/events/notifiers.h | 69 ++++++++++++++++++++++++++++++++
 kernel/notifier.c                |  6 +++
 2 files changed, 75 insertions(+)
 create mode 100644 include/trace/events/notifiers.h

Hi Arjan / Xiaoming / all, monthly ping heh

If there's any advice on how to move things here, I would appreciate!
Thanks in advance and apologies for the re-pings.

Cheers,


Guilherme