Re: [RFC][PATCH 7/7] kref: Implement using refcount_t

From: Ingo Molnar
Date: Tue Nov 15 2016 - 08:03:30 EST



* Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Tue, Nov 15, 2016 at 11:03:59AM +0100, Ingo Molnar wrote:
> > > Should I also make a CONFIG knob that implements refcount_t with the
> > > 'normal' atomic_t primitives?
> >
> > I'd suggest doing the saturation/safe-wrap semantics only for now (i.e. the
> > current patch, split into two perhaps), and reconsider if there's any complaints?
> >
> > > And possibly another knob to toggle the BUG()s into WARN()s. With the
> > > full saturation semantics WARN() is a lot safer and will not corrupt
> > > kernel state as much.
> >
> > I'd suggest changing it to a WARN() straight away, no extra knobs.
>
> OK, a little like so then? Note that the overflow tests went away
> because increments guarantee we saturate before we overflow.

Looks good to me!

Thanks,

Ingo