From 9e3d47df35abd6430fed04fb40a76c7358b1e815 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Sat, 7 Jan 2012 23:45:12 -0800 Subject: [PATCH] sysctl: Make the header lists per directory. Slightly enhance efficiency and clarity of the code by making the header list per directory instead of per set. Benchmark before: make-dummies 0 999 -> 0.63s rmmod dummy -> 0.12s make-dummies 0 9999 -> 2m35s rmmod dummy -> 18s Benchmark after: make-dummies 0 999 -> 0.32s rmmod dummy -> 0.12s make-dummies 0 9999 -> 1m17s rmmod dummy -> 17s Signed-off-by: Eric W. Biederman --- fs/proc/proc_sysctl.c | 28 +++++++++++----------------- include/linux/sysctl.h | 2 +- 2 files changed, 12 insertions(+), 18 deletions(-) diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 160d5781638e..e971ccccac4a 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -33,12 +33,12 @@ static struct ctl_table root_table[] = { { } }; static struct ctl_table_root sysctl_table_root = { - .default_set.list = LIST_HEAD_INIT(sysctl_table_root.default_set.dir.header.ctl_entry), + .default_set.dir.list = LIST_HEAD_INIT(sysctl_table_root.default_set.dir.list), .default_set.dir.header = { {{.count = 1, .nreg = 1, .ctl_table = root_table, - .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}}, + .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.dir.header.ctl_entry),}}, .ctl_table_arg = root_table, .root = &sysctl_table_root, .set = &sysctl_table_root.default_set, @@ -79,15 +79,12 @@ static int namecmp(const char *name1, int len1, const char *name2, int len2) static struct ctl_table *find_entry(struct ctl_table_header **phead, struct ctl_dir *dir, const char *name, int namelen) { - struct ctl_table_set *set = dir->header.set; struct ctl_table_header *head; struct ctl_table *entry; - list_for_each_entry(head, &set->list, ctl_entry) { + list_for_each_entry(head, &dir->list, ctl_entry) { if (head->unregistering) continue; - if (head->parent != dir) - continue; for (entry = head->ctl_table; entry->procname; entry++) { const char *procname = entry->procname; if (namecmp(procname, strlen(procname), name, namelen) == 0) { @@ -133,7 +130,7 @@ static int insert_header(struct ctl_dir *dir, struct ctl_table_header *header) err = insert_links(header); if (err) goto fail_links; - list_add_tail(&header->ctl_entry, &header->set->list); + list_add_tail(&header->ctl_entry, &header->parent->list); return 0; fail_links: header->parent = NULL; @@ -247,14 +244,12 @@ static struct ctl_table *lookup_entry(struct ctl_table_header **phead, static struct ctl_table_header *next_usable_entry(struct ctl_dir *dir, struct list_head *tmp) { - struct ctl_table_set *set = dir->header.set; struct ctl_table_header *head; - for (tmp = tmp->next; tmp != &set->list; tmp = tmp->next) { + for (tmp = tmp->next; tmp != &dir->list; tmp = tmp->next) { head = list_entry(tmp, struct ctl_table_header, ctl_entry); - if (head->parent != dir || - !head->ctl_table->procname || + if (!head->ctl_table->procname || !use_table(head)) continue; @@ -270,7 +265,7 @@ static void first_entry(struct ctl_dir *dir, struct ctl_table *entry = NULL; spin_lock(&sysctl_lock); - head = next_usable_entry(dir, &dir->header.set->list); + head = next_usable_entry(dir, &dir->list); spin_unlock(&sysctl_lock); if (head) entry = head->ctl_table; @@ -793,6 +788,7 @@ static struct ctl_dir *new_dir(struct ctl_table_set *set, new_name = (char *)(table + 2); memcpy(new_name, name, namelen); new_name[namelen] = '\0'; + INIT_LIST_HEAD(&new->list); table[0].procname = new_name; table[0].mode = S_IFDIR|S_IRUGO|S_IXUGO; init_header(&new->header, set->dir.header.root, set, table); @@ -917,12 +913,10 @@ static int sysctl_check_table_dups(struct ctl_dir *dir, struct ctl_table *old, static int sysctl_check_dups(struct ctl_dir *dir, struct ctl_table *table) { - struct ctl_table_set *set; struct ctl_table_header *head; int error = 0; - set = dir->header.set; - list_for_each_entry(head, &set->list, ctl_entry) { + list_for_each_entry(head, &dir->list, ctl_entry) { if (head->unregistering) continue; if (head->parent != dir) @@ -1494,14 +1488,14 @@ void setup_sysctl_set(struct ctl_table_set *set, int (*is_seen)(struct ctl_table_set *)) { memset(set, sizeof(*set), 0); - INIT_LIST_HEAD(&set->list); set->is_seen = is_seen; + INIT_LIST_HEAD(&set->dir.list); init_header(&set->dir.header, root, set, root_table); } void retire_sysctl_set(struct ctl_table_set *set) { - WARN_ON(!list_empty(&set->list)); + WARN_ON(!list_empty(&set->dir.list)); } int __init proc_sys_init(void) diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index cec59415b3ce..36dec756ef9d 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -1047,10 +1047,10 @@ struct ctl_table_header struct ctl_dir { /* Header must be at the start of ctl_dir */ struct ctl_table_header header; + struct list_head list; }; struct ctl_table_set { - struct list_head list; int (*is_seen)(struct ctl_table_set *); struct ctl_dir dir; }; -- GitLab