From 9dee7503ce3fc38911b9873216619190cf688128 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Tue, 5 Jul 2005 22:03:10 +0100 Subject: [JFFS2] Optimise jffs2_add_tn_to_list Use an rbtree instead of a simple linked list. We were wasting an amazing amount of time in jffs2_add_tn_to_list(). Thanks to Artem Bityuckiy and Jarkko Jlavinen for noticing. Signed-off-by: David Woodhouse Signed-off-by: Thomas Gleixner --- fs/jffs2/nodelist.c | 73 +++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 54 insertions(+), 19 deletions(-) (limited to 'fs/jffs2/nodelist.c') diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c index 8a8e4b863824..be38cc5c35cd 100644 --- a/fs/jffs2/nodelist.c +++ b/fs/jffs2/nodelist.c @@ -7,7 +7,7 @@ * * For licensing information, see the file 'LICENCE' in this directory. * - * $Id: nodelist.c,v 1.94 2005/04/13 13:22:35 dwmw2 Exp $ + * $Id: nodelist.c,v 1.95 2005/07/05 21:03:07 dwmw2 Exp $ * */ @@ -58,27 +58,61 @@ void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new /* Put a new tmp_dnode_info into the list, keeping the list in order of increasing version */ -static void jffs2_add_tn_to_list(struct jffs2_tmp_dnode_info *tn, struct jffs2_tmp_dnode_info **list) + +static void jffs2_add_tn_to_list(struct jffs2_tmp_dnode_info *tn, struct rb_root *list) { - struct jffs2_tmp_dnode_info **prev = list; - - while ((*prev) && (*prev)->version < tn->version) { - prev = &((*prev)->next); - } - tn->next = (*prev); - *prev = tn; + struct rb_node **p = &list->rb_node; + struct rb_node * parent = NULL; + struct jffs2_tmp_dnode_info *this; + + while (*p) { + parent = *p; + this = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); + + if (tn->version < this->version) + p = &(*p)->rb_left; + else if (tn->version > this->version) + p = &(*p)->rb_right; + else if (tn < this) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + rb_link_node(&tn->rb, parent, p); + rb_insert_color(&tn->rb, list); } -static void jffs2_free_tmp_dnode_info_list(struct jffs2_tmp_dnode_info *tn) +static void jffs2_free_tmp_dnode_info_list(struct rb_root *list) { - struct jffs2_tmp_dnode_info *next; + struct rb_node *this; + struct jffs2_tmp_dnode_info *tn; + + this = list->rb_node; - while (tn) { - next = tn; - tn = tn->next; - jffs2_free_full_dnode(next->fn); - jffs2_free_tmp_dnode_info(next); + /* Now at bottom of tree */ + while (this) { + if (this->rb_left) + this = this->rb_left; + else if (this->rb_right) + this = this->rb_right; + else { + tn = rb_entry(this, struct jffs2_tmp_dnode_info, rb); + jffs2_free_full_dnode(tn->fn); + jffs2_free_tmp_dnode_info(tn); + + this = this->rb_parent; + if (!this) + break; + + if (this->rb_left == &tn->rb) + this->rb_left = NULL; + else if (this->rb_right == &tn->rb) + this->rb_right = NULL; + else BUG(); + } } + list->rb_node = NULL; } static void jffs2_free_full_dirent_list(struct jffs2_full_dirent *fd) @@ -108,12 +142,13 @@ static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_r with this ino, returning the former in order of version */ int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, - struct jffs2_tmp_dnode_info **tnp, struct jffs2_full_dirent **fdp, + struct rb_root *tnp, struct jffs2_full_dirent **fdp, uint32_t *highest_version, uint32_t *latest_mctime, uint32_t *mctime_ver) { struct jffs2_raw_node_ref *ref, *valid_ref; - struct jffs2_tmp_dnode_info *tn, *ret_tn = NULL; + struct jffs2_tmp_dnode_info *tn; + struct rb_root ret_tn = RB_ROOT; struct jffs2_full_dirent *fd, *ret_fd = NULL; union jffs2_node_union node; size_t retlen; @@ -450,7 +485,7 @@ int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, return 0; free_out: - jffs2_free_tmp_dnode_info_list(ret_tn); + jffs2_free_tmp_dnode_info_list(&ret_tn); jffs2_free_full_dirent_list(ret_fd); return err; } -- cgit v1.2.3