[PATCH 2/2] staging: brcm80211: replace asserts close to Mac80211 interface
Greg KH
greg at kroah.com
Fri Mar 25 23:19:35 UTC 2011
On Sat, Mar 26, 2011 at 01:19:31AM +0300, Dan Carpenter wrote:
> On Fri, Mar 25, 2011 at 01:52:57PM +0100, Roland Vossen wrote:
> > >>
> > >>>+ if (likely(hw != NULL))
> > >>>+ wl = hw->priv;
> > >>
> > >>This isn't a fast path. The likely() here is not needed. It makes the
> > >>code less readable for no reason.
> > >
> > >Good suggestion. Agree.
> >
> > Come to think about it a bit better: I would say that the 'likely'
> > makes the code more readable since it indicates to the reader what
> > the 'sunny flow' is. Is there a common consensus on the usage of
> > likely/unlikely ?
The consensus is that is should NEVER show up in a driver.
Really, don't use it, 90% of the time it is used wrong. That other 10%
is just lucky. The compiler knows this stuff better than we do, so let
it handle it properly.
Again, never use it in a driver. If you really want to, you had better
have hard numbers as to why it matters showing a noticable improvement.
thanks,
greg k-h
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