Re: [RFC PATCH 1/1] cleanup: use bool as return type for rwsem_is_locked

Dave Chinner
2014-06-07T00:18:36Z

On Fri, Jun 06, 2014 at 02:11:18PM -0400, Pranith Kumar wrote:
> On 06/06/2014 01:53 PM, Pranith Kumar wrote:
> > On Fri, Jun 6, 2014 at 3:35 AM, Peter Zijlstra <peterz@infradead.org> wrote:
> >>
> >> Now in general, I don't particularly like such superfluous changes, so
> >> unless you can show that GCC actually generates better code, I'd prefer
> >> to keep things as they are.
> >
> > Fixed and checked the assembly. It saves us 2 bytes of code, not much. I am not sure if that is worth it :(
> >
> > use bool as the return type for rwsem_is_locked() instead of int
> >
> > Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
....

Makes sense to me.

> I observed one other user of rwsem_is_locked() in xfs, change accordingly
>
> Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
> ---
> fs/xfs/xfs_inode.c | 2 +-
> fs/xfs/xfs_inode.h | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
> index 768087b..9047eda 100644
> --- a/fs/xfs/xfs_inode.c
> +++ b/fs/xfs/xfs_inode.c
> @@ -285,7 +285,7 @@ xfs_ilock_demote(
> }
>
> #if defined(DEBUG) || defined(XFS_WARN)
> -int
> +bool
> xfs_isilocked(
> xfs_inode_t *ip,
> uint lock_flags)

If you are going to change the return type to bool, then you should
also remove the manual "!!" conversions to a boolean return and let
the compiler do it in the most optimal way.

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com