On Wed, Feb 19, 2020 at 11:15:32AM -0500, Steven Rostedt wrote:
> On Wed, 19 Feb 2020 16:58:28 +0100
> Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> > On Wed, Feb 19, 2020 at 10:49:03AM -0500, Steven Rostedt wrote:
> > > On Wed, 19 Feb 2020 15:47:32 +0100
> > > Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > > > These helpers are macros because of header-hell; they're placed here
> > > > because of the proximity to nmi_{enter,exit{().
> >
> > ^^^^
>
> Bah I can't read, because I even went looking for this!
>
> >
> > > > +#define trace_rcu_enter() \
> > > > +({ \
> > > > + unsigned long state = 0; \
> > > > + if (!rcu_is_watching()) { \
> > > > + rcu_irq_enter_irqsave(); \
> > > > + state = 1; \
> > > > + } \
> > > > + state; \
> > > > +})
> > > > +
> > > > +#define trace_rcu_exit(state) \
> > > > +do { \
> > > > + if (state) \
> > > > + rcu_irq_exit_irqsave(); \
> > > > +} while (0)
> > > > +
> > >
> > > Is there a reason that these can't be static __always_inline functions?
> >
> > It can be done, but then we need fwd declarations of those RCU functions
> > somewhere outside of rcupdate.h. It's all a bit of a mess.
>
> Maybe this belongs in the rcupdate.h file then?
Possibly, and I suppose the current version is less obviously dependent
on the in_nmi() functionality as was the previous, seeing how Paul
frobbed that all the way into the rcu_irq_enter*() implementation.
So sure, I can go move it I suppose.
