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

Pranith Kumar
2014-06-07T01:41:25Z

On 06/06/2014 08:59 PM, Pranith Kumar wrote:
> On 06/06/2014 08:18 PM, Dave Chinner wrote:
>> 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
>>>>
>
>>
>> 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.
>>
>
> Agreed, please find patch below:
>

Simplify the "!!" condition. This is much simpler. :)

change return type to bool to follow rwsem_is_locked()

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
---
fs/xfs/xfs_inode.c | 8 ++++----
fs/xfs/xfs_inode.h | 2 +-
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index a6115fe..c02ac49 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -285,25 +285,25 @@ xfs_ilock_demote(
}

#if defined(DEBUG) || defined(XFS_WARN)
-int
+bool
xfs_isilocked(
xfs_inode_t *ip,
uint lock_flags)
{
if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
if (!(lock_flags & XFS_ILOCK_SHARED))
- return !!ip->i_lock.mr_writer;
+ return (ip->i_lock.mr_writer != 0);
return rwsem_is_locked(&ip->i_lock.mr_lock);
}

if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
if (!(lock_flags & XFS_IOLOCK_SHARED))
- return !!ip->i_iolock.mr_writer;
+ return (ip->i_iolock.mr_writer != 0);
return rwsem_is_locked(&ip->i_iolock.mr_lock);
}

ASSERT(0);
- return 0;
+ return false;
}
#endif

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index f72bffa..efebed6 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -346,7 +346,7 @@ void xfs_ilock(xfs_inode_t *, uint);
int xfs_ilock_nowait(xfs_inode_t *, uint);
void xfs_iunlock(xfs_inode_t *, uint);
void xfs_ilock_demote(xfs_inode_t *, uint);
-int xfs_isilocked(xfs_inode_t *, uint);
+bool xfs_isilocked(xfs_inode_t *, uint);
uint xfs_ilock_data_map_shared(struct xfs_inode *);
uint xfs_ilock_attr_map_shared(struct xfs_inode *);
int xfs_ialloc(struct xfs_trans *, xfs_inode_t *, umode_t,
--
1.9.1