Re: [GIT PULL] adaptive spinning mutexes

Andrew Morton
2009-01-14T20:21:31Z

On Wed, 14 Jan 2009 20:50:50 +0100
Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> On Wed, 2009-01-14 at 11:36 -0800, Andrew Morton wrote:
>
> > Do people enable CONFIG_SCHED_DEBUG?
>
> Well, I have it always enabled, but I've honestly no idea if that makes
> me weird.

It'd be weird if you're not weird.

> > CONFIG_DEBUG_MUTEXES=n, CONFIG_SCHED_DEBUG=y is getting to be a pretty
> > small subset?
>
> Could be, do you fancy me doing a sysctl? shouldn't be hard.

The /sys/debug knob depends upon CONFIG_SCHED_DEBUG, I assume?

umm, yes, I do think that it would be prudent to make this control
unconditionally available. Experience tells us that any regressions
which this change causes could take a long time to turn up - sometimes
years. By which time the people who are reporting the regressions are
running packaged kernels, and if that packaged kernel didn't enable
CONFIG_SCHED_DEBUG, we're a bit screwed.

Did we end up deciding to remove the CONFIG_DEBUG_MUTEXES=n dependency?