From 0c73f18b7d95de8a007039337063a770b5fc8e7a Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 14 Jun 2007 03:45:18 +0900 Subject: sysfs: use singly-linked list for sysfs_dirent tree Make sysfs_dirent use singly linked list for its tree structure. sysfs_link_sibling() and sysfs_unlink_sibling() functions are added to handle simpler cases. It adds some complexity and cpu cycle overhead but reduced memory footprint is worthwhile on big machines. This change reduces the sizeof sysfs_dirent from 104 to 88 on 64bit and from 60 to 52 on 32bit. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/inode.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'fs/sysfs/inode.c') diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index 3eab9c46a71b..732fd7f371e0 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -284,8 +284,8 @@ void sysfs_drop_dentry(struct sysfs_dirent *sd) int sysfs_hash_and_remove(struct dentry * dir, const char * name) { - struct sysfs_dirent * sd; - struct sysfs_dirent * parent_sd; + struct sysfs_dirent **pos, *sd; + struct sysfs_dirent *parent_sd = dir->d_fsdata; int found = 0; if (!dir) @@ -295,13 +295,15 @@ int sysfs_hash_and_remove(struct dentry * dir, const char * name) /* no inode means this hasn't been made visible yet */ return -ENOENT; - parent_sd = dir->d_fsdata; mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); - list_for_each_entry(sd, &parent_sd->s_children, s_sibling) { + for (pos = &parent_sd->s_children; *pos; pos = &(*pos)->s_sibling) { + sd = *pos; + if (!sd->s_type) continue; if (!strcmp(sd->s_name, name)) { - list_del_init(&sd->s_sibling); + *pos = sd->s_sibling; + sd->s_sibling = NULL; found = 1; break; } -- cgit