[PATCH 2/6] udf: don't increment lenExtents while writing to a hole

From: Namjae Jeon
Date: Tue Oct 09 2012 - 11:09:17 EST


From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>

Incrementing lenExtents even while writing to a hole is bad
for performance as calls to udf_discard_prealloc and
udf_truncate_tail_extent would not return from start if
isize != lenExtents

Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
Signed-off-by: Ashish Sangwan <a.sangwan@xxxxxxxxxxx>
---
fs/udf/inode.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 2b77593..8266f2e 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -601,6 +601,7 @@ static sector_t inode_getblk(struct inode *inode, sector_t block,
struct udf_inode_info *iinfo = UDF_I(inode);
int goal = 0, pgoal = iinfo->i_location.logicalBlockNum;
int lastblock = 0;
+ bool isBeyondEOF;

*err = 0;
*new = 0;
@@ -680,7 +681,7 @@ static sector_t inode_getblk(struct inode *inode, sector_t block,
/* Are we beyond EOF? */
if (etype == -1) {
int ret;
-
+ isBeyondEOF = 1;
if (count) {
if (c)
laarr[0] = laarr[1];
@@ -723,6 +724,7 @@ static sector_t inode_getblk(struct inode *inode, sector_t block,
endnum = c + 1;
lastblock = 1;
} else {
+ isBeyondEOF = 0;
endnum = startnum = ((count > 2) ? 2 : count);

/* if the current extent is in position 0,
@@ -770,7 +772,8 @@ static sector_t inode_getblk(struct inode *inode, sector_t block,
*err = -ENOSPC;
return 0;
}
- iinfo->i_lenExtents += inode->i_sb->s_blocksize;
+ if (isBeyondEOF)
+ iinfo->i_lenExtents += inode->i_sb->s_blocksize;
}

/* if the extent the requsted block is located in contains multiple
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/