Re: [PATCH] rculist: fix borked __list_for_each_rcu() macro

[Mariusz Kozlowski <mk@lab.zgora.pl>]

On Wed, Dec 15, 2010 at 03:20:05PM -0800, Paul E. McKenney wrote:
> On Wed, Dec 15, 2010 at 11:11:12PM +0100, Mariusz Kozlowski wrote:
> > This restores parentheses blance.
> 
> Good catch, queued!!!
> 
> This does not actually appear to be in use anywhere in the kernel any
> more, so I queued this for 2.6.38 rather than in the 2.6.37 urgent queue.
> So, just out of curiosity, how did you find this one?

Some years ago I wrote a dumb script that walks trees of () and {}.
It catches unbalanced trees. It's dumb enough to fail with #ifdef etc,
but most of the time it does its job. It reaches unreachable code
and unused one too.

> Hmmm...  Maybe we should just delete __list_for_each_rcu.  ;-)
> 
> 							Thanx, Paul
> 
> > Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
> > ---
> >  include/linux/rculist.h |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> > 
> > diff --git a/include/linux/rculist.h b/include/linux/rculist.h
> > index f31ef61..70d3ba5 100644
> > --- a/include/linux/rculist.h
> > +++ b/include/linux/rculist.h
> > @@ -244,7 +244,7 @@ static inline void list_splice_init_rcu(struct list_head *list,
> >  #define __list_for_each_rcu(pos, head) \
> >  	for (pos = rcu_dereference_raw(list_next_rcu(head)); \
> >  		pos != (head); \
> > -		pos = rcu_dereference_raw(list_next_rcu((pos)))
> > +		pos = rcu_dereference_raw(list_next_rcu(pos)))
> > 
> >  /**
> >   * list_for_each_entry_rcu	-	iterate over rcu list of given type
> > -- 
> > 1.7.0.4
> > 

-- 
Mariusz Kozlowski