lkml.org 
[lkml]   [2014]   [Dec]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] printk: add per console loglevel
On Sun, Dec 21, 2014 at 07:47:53PM +0100, Bruno Prémont wrote:
> On Sat, 20 December 2014 dwalker@fifo99.com wrote:
> > This adds to to the console= command line options allowing the
> > addition of a per console log level setting.
> >
> > examples,
> >
> > console=ttyS0,ll4
> > console=tty0,ll6
> >
> > This can be used on systems which have multiple serial consoles, but
> > it's desired for logging to be light on one and heavy on another.
>
> Looks useful to me.
> What would be the best way to make these per-console loglevels
> configurable at runtime? `dmesg -n $LEVEL` only affects the global
> limit.
>
> One drawback to letting global loglevel have precedence is that
> all consoles that should not get detailed log messages need to have
> their loglevel explicitly lowered and it's not possible to have
> one console forced to show more than the global loglevel.

Right, reason for the patch.

>
> An approach I would prefer is to have all consoles follow global
> loglevel except when something different had been explicitly requested
> for them.

This patch is mostly like this. It breaks down when you set the "llX"
parameter to something above KERN_NOTICE, and the global one is also
set above that.

> This way a single console can be added later on (e.g. netconsole)
> and set to pass through debug messages without affecting anyone else.

Not following the "added later" part.

Daniel


\
 
 \ /
  Last update: 2014-12-23 18:01    [W:0.111 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site