Re: [PATCH] staging: nvec: fixed few coding style warnings

From: Dan Carpenter
Date: Thu Oct 15 2015 - 04:48:34 EST


On Thu, Oct 15, 2015 at 10:39:02AM +0200, Marc Dietrich wrote:
> > > - if (unlikely(nvec->rx == NULL)) {
> > > + if (!unlikely(nvec->rx)) {
> >
> > This isn't right. You intented to say:
> >
> > if (unlikely(!nvec->rx)) {
> >
> > But even better to just remove the unlikely entirely.
> >
> > if (!nvec->rx) {
>
> why? the "unlikely" is there to optimize a critical interrupt path.

The rule is that drivers should not use likely/unlikely() unless there
is a difference in benchmark numbers. How critical can it be when it's
always followed by a udelay(100)???

There are more important optimizations needed here.

regards,
dan carpenter

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