* Dave Jones <davej(a)redhat.com> wrote:
It's crossed my mind to turn it on occasionally in rawhide just
to
shake out those hard to find bugs. The thing that's put me off has
been that well, we've got enough bugs already without needing to find
more right now.
it's on by default in -rt and i havent had a bug triggered by it for
quite a long time. We had many SMP races triggered by PREEMPT_RT.
part of the reason of PREEMPT_BKL's reliability is because when i did it
i also wrote debugging infrastructure to catch bugs that would only
trigger on PREEMPT_BKL=y: the smp_processor_id() debugging code of
CONFIG_DEBUG_PREEMPT. (and that infrastructure, like lockdep, catches
bugs before they actually happen, by flagging buggy codepath the first
time it ever executes)
Ingo