sysctl: Remove register_sysctl_table

This is part of the general push to deprecate register_sysctl_paths and
register_sysctl_table. After removing all the calling functions, we
remove both the register_sysctl_table function and the documentation
check that appeared in check-sysctl-docs awk script.

We save 595 bytes with this change:

./scripts/bloat-o-meter vmlinux.1.refactor-base-paths vmlinux.2.remove-sysctl-table
add/remove: 2/8 grow/shrink: 1/0 up/down: 1154/-1749 (-595)
Function                                     old     new   delta
count_subheaders                               -     983    +983
unregister_sysctl_table                       29     184    +155
__pfx_count_subheaders                         -      16     +16
__pfx_unregister_sysctl_table.part            16       -     -16
__pfx_register_leaf_sysctl_tables.constprop   16       -     -16
__pfx_count_subheaders.part                   16       -     -16
__pfx___register_sysctl_base                  16       -     -16
unregister_sysctl_table.part                 136       -    -136
__register_sysctl_base                       478       -    -478
register_leaf_sysctl_tables.constprop        524       -    -524
count_subheaders.part                        547       -    -547
Total: Before=21257652, After=21257057, chg -0.00%

[mcgrof: remove register_leaf_sysctl_tables and append_path too and
 add bloat-o-meter stats]

Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index f8f19e0..8873812 100644 (file)
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -1466,19 +1466,6 @@ void __init __register_sysctl_init(const char *path, struct ctl_table *table,
        kmemleak_not_leak(hdr);
 }
 
-static char *append_path(const char *path, char *pos, const char *name)
-{
-       int namelen;
-       namelen = strlen(name);
-       if (((pos - path) + namelen + 2) >= PATH_MAX)
-               return NULL;
-       memcpy(pos, name, namelen);
-       pos[namelen] = '/';
-       pos[namelen + 1] = '\0';
-       pos += namelen + 1;
-       return pos;
-}
-
 static int count_subheaders(struct ctl_table *table)
 {
        int has_files = 0;
@@ -1498,152 +1485,6 @@ static int count_subheaders(struct ctl_table *table)
        return nr_subheaders + has_files;
 }
 
-static int register_leaf_sysctl_tables(const char *path, char *pos,
-       struct ctl_table_header ***subheader, struct ctl_table_set *set,
-       struct ctl_table *table)
-{
-       struct ctl_table *ctl_table_arg = NULL;
-       struct ctl_table *entry, *files;
-       int nr_files = 0;
-       int nr_dirs = 0;
-       int err = -ENOMEM;
-
-       list_for_each_table_entry(entry, table) {
-               if (entry->child)
-                       nr_dirs++;
-               else
-                       nr_files++;
-       }
-
-       files = table;
-       /* If there are mixed files and directories we need a new table */
-       if (nr_dirs && nr_files) {
-               struct ctl_table *new;
-               files = kcalloc(nr_files + 1, sizeof(struct ctl_table),
-                               GFP_KERNEL);
-               if (!files)
-                       goto out;
-
-               ctl_table_arg = files;
-               new = files;
-
-               list_for_each_table_entry(entry, table) {
-                       if (entry->child)
-                               continue;
-                       *new = *entry;
-                       new++;
-               }
-       }
-
-       /* Register everything except a directory full of subdirectories */
-       if (nr_files || !nr_dirs) {
-               struct ctl_table_header *header;
-               header = __register_sysctl_table(set, path, files);
-               if (!header) {
-                       kfree(ctl_table_arg);
-                       goto out;
-               }
-
-               /* Remember if we need to free the file table */
-               header->ctl_table_arg = ctl_table_arg;
-               **subheader = header;
-               (*subheader)++;
-       }
-
-       /* Recurse into the subdirectories. */
-       list_for_each_table_entry(entry, table) {
-               char *child_pos;
-
-               if (!entry->child)
-                       continue;
-
-               err = -ENAMETOOLONG;
-               child_pos = append_path(path, pos, entry->procname);
-               if (!child_pos)
-                       goto out;
-
-               err = register_leaf_sysctl_tables(path, child_pos, subheader,
-                                                 set, entry->child);
-               pos[0] = '\0';
-               if (err)
-                       goto out;
-       }
-       err = 0;
-out:
-       /* On failure our caller will unregister all registered subheaders */
-       return err;
-}
-
-/**
- * register_sysctl_table - register a sysctl table hierarchy
- * @table: the top-level table structure
- *
- * Register a sysctl table hierarchy. @table should be a filled in ctl_table
- * array. A completely 0 filled entry terminates the table.
- * We are slowly deprecating this call so avoid its use.
- */
-static struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
-{
-       struct ctl_table *ctl_table_arg = table;
-       int nr_subheaders = count_subheaders(table);
-       struct ctl_table_header *header = NULL, **subheaders, **subheader;
-       char *new_path, *pos;
-
-       pos = new_path = kmalloc(PATH_MAX, GFP_KERNEL);
-       if (!new_path)
-               return NULL;
-
-       pos[0] = '\0';
-       while (table->procname && table->child && !table[1].procname) {
-               pos = append_path(new_path, pos, table->procname);
-               if (!pos)
-                       goto out;
-               table = table->child;
-       }
-       if (nr_subheaders == 1) {
-               header = __register_sysctl_table(&sysctl_table_root.default_set, new_path, table);
-               if (header)
-                       header->ctl_table_arg = ctl_table_arg;
-       } else {
-               header = kzalloc(sizeof(*header) +
-                                sizeof(*subheaders)*nr_subheaders, GFP_KERNEL);
-               if (!header)
-                       goto out;
-
-               subheaders = (struct ctl_table_header **) (header + 1);
-               subheader = subheaders;
-               header->ctl_table_arg = ctl_table_arg;
-
-               if (register_leaf_sysctl_tables(new_path, pos, &subheader,
-                                               &sysctl_table_root.default_set, table))
-                       goto err_register_leaves;
-       }
-
-out:
-       kfree(new_path);
-       return header;
-
-err_register_leaves:
-       while (subheader > subheaders) {
-               struct ctl_table_header *subh = *(--subheader);
-               struct ctl_table *table = subh->ctl_table_arg;
-               unregister_sysctl_table(subh);
-               kfree(table);
-       }
-       kfree(header);
-       header = NULL;
-       goto out;
-}
-
-int __register_sysctl_base(struct ctl_table *base_table)
-{
-       struct ctl_table_header *hdr;
-
-       hdr = register_sysctl_table(base_table);
-       kmemleak_not_leak(hdr);
-       return 0;
-}
-
 static void put_links(struct ctl_table_header *header)
 {
        struct ctl_table_set *root_set = &sysctl_table_root.default_set;

diff --git a/scripts/check-sysctl-docs b/scripts/check-sysctl-docs
index edc9a62..4f163e0 100755 (executable)
--- a/scripts/check-sysctl-docs
+++ b/scripts/check-sysctl-docs
@@ -146,16 +146,6 @@ curtable && /\.procname[\t ]*=[\t ]*".+"/ {
     children[curtable][curentry] = child
 }
 
-/register_sysctl_table\(.*\)/ {
-    match($0, /register_sysctl_table\(([^)]+)\)/, tables)
-    if (debug) print "Registering table " tables[1]
-    if (children[tables[1]][table]) {
-       for (entry in entries[children[tables[1]][table]]) {
-           printentry(entry)
-       }
-    }
-}
-
 END {
     for (entry in documented) {
        if (!seen[entry]) {