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sysfs: make sysfs_add/remove_one() call link/unlink_sibling() implictly

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When adding or removing a sysfs_dirent, the user used to be required
to call link/unlink separately.  It was for two reasons - code looked
like that before sysfs_addrm_cxt conversion and to avoid looping
through parent_sd->children list twice during removal.

Performance optimization during removal just isn't worth it.  Make
sysfs_add/remove_one() call sysfs_link/unlink_sibing() implicitly.
This makes code simpler albeit slightly less efficient.  This change
doesn't introduce any noticeable behavior change.

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>
This commit is contained in:
Tejun Heo
2007-08-02 21:38:03 +09:00
committed by Greg Kroah-Hartman
parent ff869de7bf
commit 41fc1c2745
5 changed files with 16 additions and 32 deletions
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21
fs/sysfs/dir.c
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@ -30,7 +30,7 @@ static DEFINE_IDA(sysfs_ino_ida);
* Locking:
* mutex_lock(sysfs_mutex)
*/
void sysfs_link_sibling(struct sysfs_dirent *sd)
static void sysfs_link_sibling(struct sysfs_dirent *sd)
{
struct sysfs_dirent *parent_sd = sd->s_parent;
@ -49,7 +49,7 @@ void sysfs_link_sibling(struct sysfs_dirent *sd)
* Locking:
* mutex_lock(sysfs_mutex)
*/
void sysfs_unlink_sibling(struct sysfs_dirent *sd)
static void sysfs_unlink_sibling(struct sysfs_dirent *sd)
{
struct sysfs_dirent **pos;
@ -500,6 +500,8 @@ void sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
inc_nlink(acxt->parent_inode);
acxt->cnt++;
sysfs_link_sibling(sd);
}
/**
@ -521,7 +523,9 @@ void sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
*/
void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
BUG_ON(sd->s_sibling || (sd->s_flags & SYSFS_FLAG_REMOVED));
BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED);
sysfs_unlink_sibling(sd);
sd->s_flags |= SYSFS_FLAG_REMOVED;
sd->s_sibling = acxt->removed;
@ -697,10 +701,8 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
/* link in */
sysfs_addrm_start(&acxt, parent_sd);
if (!sysfs_find_dirent(parent_sd, name)) {
if (!sysfs_find_dirent(parent_sd, name))
sysfs_add_one(&acxt, sd);
sysfs_link_sibling(sd);
}
if (!sysfs_addrm_finish(&acxt)) {
sysfs_put(sd);
@ -821,7 +823,6 @@ static void remove_dir(struct sysfs_dirent *sd)
struct sysfs_addrm_cxt acxt;
sysfs_addrm_start(&acxt, sd->s_parent);
sysfs_unlink_sibling(sd);
sysfs_remove_one(&acxt, sd);
sysfs_addrm_finish(&acxt);
}
@ -846,11 +847,9 @@ static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd)
while (*pos) {
struct sysfs_dirent *sd = *pos;
if (sysfs_type(sd) && sysfs_type(sd) != SYSFS_DIR) {
*pos = sd->s_sibling;
sd->s_sibling = NULL;
if (sysfs_type(sd) && sysfs_type(sd) != SYSFS_DIR)
sysfs_remove_one(&acxt, sd);
} else
else
pos = &(*pos)->s_sibling;
}
sysfs_addrm_finish(&acxt);