Re: [PATCH 1/4] dynamic_debug: consolidate repetitive struct _ddebug descriptor definitions

[Joe Perches <joe@perches.com>]

On Fri, 2011-09-09 at 13:23 -0600, Jim Cromie wrote:
> It also allows for "lite" usage of dynamic-debug,
> including 1..few descriptor per file or module to control all debug printing.
> As outlined, this "lite" usage is determined by the coder,
> it would be cool if it were more configurable than that,
> but I dont see how that would work atm.

General problem is that there are subsystems that use
bitmasks with more than a just a few bits defined.

> Now that the worms have escaped the can, one other thought:
> 	unsigned int lineno:24;
> allows for insanely large files.  The largest in the tree is 29k,
> 16 bits would cover all files likely to be accepted in the future.

I hope ever.

> Since since it works with module/file/function filtering, 3-4 user
> flags should be plenty.

I rather doubt it as there are both level and mask uses.

There is no real issue with adding another flag value
to the struct anyway.  It's declared __aligned(8) and
it ends in an unaligned single char so there's space
for another u32 without extending the structure size.