[PATCH 00/50] Add log level to show_stack()

[Sergey Senozhatsky]

On (19/11/11 10:12), Petr Mladek wrote:
[..]
> > I do recall that we talked about per-CPU printk state bit which would
> > start/end "just print it" section. We probably can extend it to "just
> > log_store" type of functionality. Doesn't look like a very bad idea.
> 
> The problem with per-CPU printk is that we would need to disable
> interrupts.

Or disable preemption and have loglevel per-CPU and per-context.
preempt_count can navigate us to the right context loglevel on
particular CPU. I'm talking here only about backtrace (error)
reporting contexts. Those can be atomic perfectly fine.

I posted a silly code snippet.

[..]
> But yes, this per-code-section loglevel is problematic. The feedback
> against the patchset shows that people want it also the other way.
> I mean to keep pr_debug() as pr_debug().

Hmm. Right.

> A solution might be to use the per-code-section loglevel only instead
> of some special loglevel.

So maybe we can "overwrite" only KERN_DEFAULT loglevels?
We certainly should not mess with SCHED or with anything in between
EMERG and ERR.

> The explicitly passed loglevel makes me feel more confident that
> all needed printk() calls were updated. But it might be a false
> feeling. I do not really have any strong preference.

I'm not like really objecting, just trying to explore some other
options.

	-ss