xfs_bmap_util: use swap macro

PATCH Superseded Gustavo A. R. Silva 2 participants 3 messages Jul 9, 2018 XFS filesystem

Share & tools

Gustavo A. R. Silva

author

2018-07-09 14:06 UTC #0 lore raw

PATCH 1/1 xfs_bmap_util: use swap macro

Make use of the swap macro and remove some unnecessary variables. This makes the code easier to read and maintain. Also, reduces the stack usage.

This code was detected with the help of Coccinelle.

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
 fs/xfs/xfs_bmap_util.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

fs/xfs/xfs_bmap_util.c +2 ~~-11~~

index 83b1e8c..4b0b16f 100644
@@ -1691,7 +1691,6 @@ xfs_swap_extent_forks(
 	int			*src_log_flags,
 	int			*target_log_flags)
 {
-	struct xfs_ifork	tempifp, *ifp, *tifp;
 	xfs_filblks_t		aforkblks = 0;
 	xfs_filblks_t		taforkblks = 0;
 	xfs_extnum_t		junk;

@@ -1733,11 +1732,7 @@ xfs_swap_extent_forks(
 	/*
 	 * Swap the data forks of the inodes
 	 */
-	ifp = &ip->i_df;
-	tifp = &tip->i_df;
-	tempifp = *ifp;		/* struct copy */
-	*ifp = *tifp;		/* struct copy */
-	*tifp = tempifp;	/* struct copy */
+	swap(ip->i_df, tip->i_df);
 
 	/*
 	 * Fix the on-disk inode values

@@ -1987,14 +1982,10 @@ xfs_swap_extents(
 
 	/* Swap the cow forks. */
 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
-		xfs_extnum_t	extnum;
-
 		ASSERT(ip->i_cformat == XFS_DINODE_FMT_EXTENTS);
 		ASSERT(tip->i_cformat == XFS_DINODE_FMT_EXTENTS);
 
-		extnum = ip->i_cnextents;
-		ip->i_cnextents = tip->i_cnextents;
-		tip->i_cnextents = extnum;
+		swap(ip->i_cnextents, tip->i_cnextents);
 
 		cowfp = ip->i_cowfp;
 		ip->i_cowfp = tip->i_cowfp;

Signature · 1 line

2.7.4

Darrick J. Wong

2018-07-09 16:39 UTC #1 lore raw

Quoted 26 lines · Gustavo A. R. Silva

Make use of the swap macro and remove some unnecessary variables. This makes the code easier to read and maintain. Also, reduces the stack usage.
This code was detected with the help of Coccinelle.
Signed-off-by Gustavo A. R. Silva <[email protected]>
---
 fs/xfs/xfs_bmap_util.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)
fs/xfs/xfs_bmap_util.c +0 -1
index 83b1e8c..4b0b16f 100644
@@ -1691,7 +1691,6 @@ xfs_swap_extent_forks(
 	int			*src_log_flags,
 	int			*target_log_flags)
 {
-	struct xfs_ifork	tempifp, *ifp, *tifp;
 	xfs_filblks_t		aforkblks = 0;
 	xfs_filblks_t		taforkblks = 0;
 	xfs_extnum_t		junk;
@@ -1733,11 +1732,7 @@ xfs_swap_extent_forks(
 	/*
 	 * Swap the data forks of the inodes

fs/xfs/xfs_bmap_util.c xfs_swap_extent_forks( · line 1738

Quoted 10 lines

fs/xfs/xfs_bmap_util.c +1 -5

 	 */
-	ifp = &ip->i_df;
-	tifp = &tip->i_df;
-	tempifp = *ifp;		/* struct copy */
-	*ifp = *tifp;		/* struct copy */
-	*tifp = tempifp;	/* struct copy */
+	swap(ip->i_df, tip->i_df);
 
 	/*
 	 * Fix the on-disk inode values

Why not use swap() on the di_nextents and di_format exchange below here too?

Quoted 6 lines

fs/xfs/xfs_bmap_util.c +0 -2

@@ -1987,14 +1982,10 @@ xfs_swap_extents(
 
 	/* Swap the cow forks. */
 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
-		xfs_extnum_t	extnum;
-

fs/xfs/xfs_bmap_util.c xfs_swap_extents( · line 1991

Quoted 10 lines

fs/xfs/xfs_bmap_util.c +1 -3

 		ASSERT(ip->i_cformat == XFS_DINODE_FMT_EXTENTS);
 		ASSERT(tip->i_cformat == XFS_DINODE_FMT_EXTENTS);
 
-		extnum = ip->i_cnextents;
-		ip->i_cnextents = tip->i_cnextents;
-		tip->i_cnextents = extnum;
+		swap(ip->i_cnextents, tip->i_cnextents);
 
 		cowfp = ip->i_cowfp;
 		ip->i_cowfp = tip->i_cowfp;

Same here -- why not use swap on {ip,tip}->i_cowfp?

--D

Quoted 7 lines

Signature · 6 lines

2.7.4

--
To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Gustavo A. R. Silva

author

2018-07-09 16:43 UTC #2 lore raw

Hi Darrick,

Quoted 55 lines · Darrick J. Wong

Quoted 26 lines · Gustavo A. R. Silva

Make use of the swap macro and remove some unnecessary variables. This makes the code easier to read and maintain. Also, reduces the stack usage.
This code was detected with the help of Coccinelle.
Signed-off-by Gustavo A. R. Silva <[email protected]>
---
 fs/xfs/xfs_bmap_util.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)
fs/xfs/xfs_bmap_util.c +0 -1
index 83b1e8c..4b0b16f 100644
@@ -1691,7 +1691,6 @@ xfs_swap_extent_forks(
 	int			*src_log_flags,
 	int			*target_log_flags)
 {
-	struct xfs_ifork	tempifp, *ifp, *tifp;
 	xfs_filblks_t		aforkblks = 0;
 	xfs_filblks_t		taforkblks = 0;
 	xfs_extnum_t		junk;
@@ -1733,11 +1732,7 @@ xfs_swap_extent_forks(
 	/*
 	 * Swap the data forks of the inodes

fs/xfs/xfs_bmap_util.c xfs_swap_extent_forks( · line 1738

Quoted 10 lines

fs/xfs/xfs_bmap_util.c +1 -5

 	 */
-	ifp = &ip->i_df;
-	tifp = &tip->i_df;
-	tempifp = *ifp;		/* struct copy */
-	*ifp = *tifp;		/* struct copy */
-	*tifp = tempifp;	/* struct copy */
+	swap(ip->i_df, tip->i_df);
 
 	/*
 	 * Fix the on-disk inode values

Why not use swap() on the di_nextents and di_format exchange below here too?

Quoted 14 lines

fs/xfs/xfs_bmap_util.c +1 -5

@@ -1987,14 +1982,10 @@ xfs_swap_extents(
 
 	/* Swap the cow forks. */
 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
-		xfs_extnum_t	extnum;
-
 		ASSERT(ip->i_cformat == XFS_DINODE_FMT_EXTENTS);
 		ASSERT(tip->i_cformat == XFS_DINODE_FMT_EXTENTS);
 
-		extnum = ip->i_cnextents;
-		ip->i_cnextents = tip->i_cnextents;
-		tip->i_cnextents = extnum;
+		swap(ip->i_cnextents, tip->i_cnextents);

Quoted 5 lines

fs/xfs/xfs_bmap_util.c xfs_swap_extents( · line 1991
Quoted 2 lines
fs/xfs/xfs_bmap_util.c +0 -0
 		cowfp = ip->i_cowfp;
 		ip->i_cowfp = tip->i_cowfp;
Same here -- why not use swap on {ip,tip}->i_cowfp?

Yep. I'll send a new patch shortly.

Thanks for the feedback.
--
Gustavo