Re: [PATCH] printk: support structured and multi-facility log messages

[Joe Perches <joe@perches.com>]

On Thu, 2012-04-05 at 18:31 -0700, Linus Torvalds wrote:
> On Thu, Apr 5, 2012 at 6:12 PM, Joe Perches <joe@perches.com> wrote:
> >
> > I still think this should be 3 patches not 1.
> 
> I do agree that that would be lovely. That patch is really hard to
> read, and it would be helpful if some of it was split up a bit. For
> example, separating out the "move log buffer to be packetized"
> (without actually doing the new things) from for the "introduce new
> interfaces" would be quite nice.
> 
> In fact, I think I could merge something that does the packetization
> early, if it is fairly obvious that it doesn't do anything else. Just
> making the dmesg ASCII timestamp be something that is a "read buffer"
> time thing rather than "generate printk" time thing would be nice, and
> I think the sequence numbers can be useful even with all the old
> interfaces.
> 
> So if somebody wants to help with things like that, and try to turn
> this into a more gradual thing, I think we could merge at least some
> initial parts of this patch even for 3.4.
> 
> Anybody interested?

I think it'll be a lot more sensible to
integrate this into a more granular printk
subsystem so I've just done a move and
split up of the printk bits.

kernel/printk.c -> kernel/printk/printk.c
and a breakup of printk.c into 4 parts

kernel/printk/log_buf.[ch]
kernel/printk/console.[ch]
kernel/printk/kmsg.[ch]
kernek/printk/printk.c

I think that's a lot more readable/extensible
and will make adding a new printk_emit and
devkmsg a bit simpler to understand as well.

Maybe it'd be useful to then add some compression
to the log_buf message string bits.

I'll submit that move/separate tomorrow but not
any compression after a few more compilation tests
w/ & w/o the appropriate CONFIG_ options.

Kay would have to respin though.