Re: [PATCH] inotify: fix minmax.cocci warnings

From: Julia Lawall
Date: Wed Apr 07 2021 - 13:03:03 EST




On Wed, 7 Apr 2021, Jan Kara wrote:

> On Tue 06-04-21 22:49:26, Julia Lawall wrote:
> > From: kernel test robot <lkp@xxxxxxxxx>
> >
> > Opportunity for min().
> >
> > Generated by: scripts/coccinelle/misc/minmax.cocci
> >
> > Fixes: 8636e3295ce3 ("coccinelle: misc: add minmax script")
> > CC: Denis Efremov <efremov@xxxxxxxxx>
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > Signed-off-by: kernel test robot <lkp@xxxxxxxxx>
> > Signed-off-by: Julia Lawall <julia.lawall@xxxxxxxx>
> ...
> > --- a/fs/notify/inotify/inotify_user.c
> > +++ b/fs/notify/inotify/inotify_user.c
> > @@ -382,7 +382,7 @@ static int inotify_add_to_idr(struct idr
> >
> > spin_unlock(idr_lock);
> > idr_preload_end();
> > - return ret < 0 ? ret : 0;
> > + return min(ret, 0);
> > }
>
> Honestly, while previous expression is a standard idiom for "if 'ret' holds
> an error, return it", the new expression is harder to understand for me. So
> I prefer to keep things as they are in this particular case...

OK, I had doubts about it as well, but I forwarded it because I found them
equally obscure...

Denis, maybe the semantic patch should be updated to avoid this case.

julia