Re: [PATCH 3/3] kernel/smp: add more data to CSD lock debugging

From: Paul E. McKenney
Date: Sun Feb 28 2021 - 19:08:47 EST


On Fri, Feb 26, 2021 at 10:05:51PM +0100, Peter Zijlstra wrote:
> On Fri, Feb 26, 2021 at 10:12:05AM -0800, Paul E. McKenney wrote:
> > On Fri, Feb 26, 2021 at 05:38:44PM +0100, Peter Zijlstra wrote:
> > >
> > > I hate all of this, but if this will finally catch the actual problem,
> > > we can then revert all this, so sure.
> >
> > OK, I will bite... What exactly do you hate about it?
>
> It's ugly and messy. We're basically commiting a debug session. Normally
> gunk like this is done in private trees, then we find the problem and
> fix that and crap like this never sees the light of day.

Is your hatred due to the presence of debug code at all, or a belief that
this code is unlikely to be useful in any subsequent IPI-related bug hunt?

Thanx, Paul