Re: [PATCH RFC v5 3/6] srcu: Add notrace variant of srcu_dereference

[Steven Rostedt]

On Tue, 1 May 2018 07:18:17 -0700
"Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote:


> > diff --git a/include/linux/srcu.h b/include/linux/srcu.h
> > index 2ec618979b20..a1c4947be877 100644
> > --- a/include/linux/srcu.h
> > +++ b/include/linux/srcu.h
> > @@ -135,6 +135,11 @@ static inline int srcu_read_lock_held(const struct srcu_struct *sp)
> >   */
> >  #define srcu_dereference(p, sp) srcu_dereference_check((p), (sp), 0)
> > 
> > +/**
> > + * srcu_dereference_notrace - no tracing and no lockdep calls from here
> > + */
> > +#define srcu_dereference_notrace(p, sp) srcu_dereference_check((p), (sp), 1)  
> 
> Given that this is a one-liner, why not just use srcu_dereference_check()
> directly, with 1 as you do above to disable lockdep?

I prefer what Joel did. It documents why we are doing this. Open coding
the call directly will just confuse others that touch tracepoint code.

-- Steve