[PATCH 58/75] sysfs: kill unnecessary sysfs_get() in open paths

Greg Kroah-Hartman
2007-10-12T22:52:50Z

From: Tejun Heo <htejun@gmail.com>

There's no reason to get an extra reference to sysfs_dirent for an
open file. Open file has a reference to the dentry which in turn has
a reference to sysfs_dirent. This is fairly obvious as otherwise open
itself won't be able to access the sysfs_dirent. Kill the extra
sysfs_get() and matching sysfs_put().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
fs/sysfs/bin.c | 4 +---
fs/sysfs/file.c | 6 +-----
2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index a819a7e..e93fe5e 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -193,9 +193,8 @@ static int open(struct inode * inode, struct file * file)
mutex_init(&bb->mutex);
file->private_data = bb;

- /* open succeeded, put active reference and pin attr_sd */
+ /* open succeeded, put active reference */
sysfs_put_active(attr_sd);
- sysfs_get(attr_sd);
return 0;

err_out:
@@ -211,7 +210,6 @@ static int release(struct inode * inode, struct file * file)

if (bb->mmapped)
sysfs_put_active_two(attr_sd);
- sysfs_put(attr_sd);
kfree(bb->buffer);
kfree(bb);
return 0;
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 61a8c19..73333dc 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -298,9 +298,8 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
buffer->ops = ops;
file->private_data = buffer;

- /* open succeeded, put active references and pin attr_sd */
+ /* open succeeded, put active references */
sysfs_put_active_two(attr_sd);
- sysfs_get(attr_sd);
return 0;

err_out:
@@ -310,11 +309,8 @@ static int sysfs_open_file(struct inode *inode, struct file *file)

static int sysfs_release(struct inode * inode, struct file * filp)
{
- struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
struct sysfs_buffer *buffer = filp->private_data;

- sysfs_put(attr_sd);
-
if (buffer) {
if (buffer->page)
free_page((unsigned long)buffer->page);
--
1.5.3.4