LOCK_PROFILING in -stable

[Alfred Perlstein]

* Kris Kennaway <kris at FreeBSD.org> [071021 01:56] wrote:
> Alfred Perlstein wrote:
> >* Robert Watson <rwatson at FreeBSD.org> [071020 10:21] wrote:
> >>On Sat, 20 Oct 2007, Kris Kennaway wrote:
> >>
> >>>Alfred Perlstein wrote:
> >>>>Hey guys, I have LOCK_PROFILING done for a product based on FreeBSD-6, 
> >>>>this means I can relatively easily backport LOCK_PROFILING from 
> >>>>FreeBSD-7 to FreeBSD-6.
> >>>>
> >>>>Do we want this?
> >>>>
> >>>>I'd like to do it if people want it.
> >>>I think it should be done, performance is a lot better than the old 6.x 
> >>>version and it also adds another very useful performance metric (time 
> >>>spent waiting for the lock).  The only concern is that it doesn't break 
> >>>ABI support when not compiled in, but I'm pretty sure you've already 
> >>>told me this is OK. Thanks for looking at this.
> >>This is my feeling also -- I would consider ABI breakage a show stopper 
> >>for 6.x, but feel otherwise that the new code is much more mature and 
> >>capable and would be quite beneficial to people building appliances and 
> >>related products on 6.x. You might check with Attilio about whether there 
> >>are any remaining outstanding issues that need to be resolved first, and 
> >>make sure to send a heads up out on stable@ and put a note in UPDATING 
> >>that the option and details have changed.
> >
> >I still get confused as to the meaning of this...
> >
> >It only breaks ABI when it's enabled.
> >
> >I think that is OK, right?
> >
> 
> Yes, that is fine.  Other existing debugging options also break ABI when 
> enabled, so it's OK.

OK, I should have something over the next couple of weeks.

-- 
- Alfred Perlstein