Re: [PATCH v3 1/7] Documentation: dynamic-debug: Add description of level bitmask

[Greg Kroah-Hartman]

On Tue, Jun 09, 2020 at 11:35:31PM -0700, Joe Perches wrote:
> On Wed, 2020-06-10 at 08:31 +0200, Greg Kroah-Hartman wrote:
> > On Tue, Jun 09, 2020 at 09:58:07AM -0700, Joe Perches wrote:
> > > On Tue, 2020-06-09 at 13:16 +0200, Greg Kroah-Hartman wrote:
> > > > What is wrong with the existing control of dynamic
> > > > debug messages that you want to add another type of arbitrary grouping
> > > > to it? 
> > > 
> > > There is no existing grouping mechanism.
> > 
> > info/warn/err/dbg is what I am referring to.
> > 
> > > Many drivers and some subsystems used an internal one
> > > before dynamic debug.
> > > 
> > > $ git grep "MODULE_PARM.*\bdebug\b"|wc -l
> > > 501
> > 
> > Yes, and it's horrid and needs to be cleaned up, not added to.
> 
> Or unified so driver authors have a standardized mechanism
> rather than reinventing or doing things differently.

But each "level" you all come up with will be intrepreted differently
per driver, causing total confusion (like we have today.)  Try to make
it better by just removing that mess.

> > In the beginning, yes, adding loads of different types of debugging
> > options to a driver is needed by the author, but by the time it is added
> > to the kernel, all of that should be able to be removed and only a
> > single "enable debug" should be all that is needed.
> 
> No one does that.

We did that for USB drivers a decade ago, it can be done.

greg k-h