Re: [dpdk-dev] [PATCH 2/2] ring: empty optimization

["Morten Brørup" <mb@smartsharesystems.com>]

> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Stephen Hemminger
> Sent: Tuesday, May 19, 2020 5:52 PM
> 
> On Tue, 19 May 2020 15:27:25 +0000
> Morten Brørup <mb@smartsharesystems.com> wrote:
> 
> > diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
> > index 9078e7c24..f67141482 100644
> > --- a/lib/librte_ring/rte_ring.h
> > +++ b/lib/librte_ring/rte_ring.h
> > @@ -733,7 +733,9 @@ rte_ring_full(const struct rte_ring *r)
> >  static inline int
> >  rte_ring_empty(const struct rte_ring *r)
> >  {
> > -	return rte_ring_count(r) == 0;
> > +	uint32_t prod_tail = r->prod.tail;
> > +	uint32_t cons_tail = r->cons.tail;
> > +	return cons_tail == prod_tail;
> >  }
> 
> Blank line after declarations?
> 
> Are the temporary variable even needed?

Personally, I agree with you, but I was trying to match the existing coding style of the closely related rte_ring_count() function - only to avoid this kind of feedback.

Damn if you do, damn if you don't. :-)