Re: [PATCH 4/7] audit: optimize add to parent skipping needless search and consuming parent ref

When parent has just been created there is no need to search for the parent in the list. Add a parameter to skip the search

and consume the parent reference no matter what happens.

Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; --- kernel/audit_watch.c | 23 +++++++++++++++-------- 1 files changed, 15 insertions(+), 8 deletions(-) diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index ad9c168..f209448 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -372,15 +372,20 @@ static int audit_get_nd(struct audit_watch *watch, struct path *parent) } /* Associate the given rule with an existing parent. - * Caller must hold audit_filter_mutex. */ + * Caller must hold audit_filter_mutex. + * Consumes parent reference. */ static void audit_add_to_parent(struct audit_krule *krule, - struct audit_parent *parent) + struct audit_parent *parent, + int new) { struct audit_watch *w, *watch = krule->watch; int watch_found = 0; BUG_ON(!mutex_is_locked(&audit_filter_mutex)); + if (new) + goto not_found; + list_for_each_entry(w, &parent->watches, wlist) { if (strcmp(watch->path, w->path)) continue; @@ -396,12 +401,15 @@ static void audit_add_to_parent(struct audit_krule *krule, break; } +not_found: if (!watch_found) { - audit_get_parent(parent); watch->parent = parent; list_add(&watch->wlist, &parent->watches); - } + } else + /* match get in audit_find_parent or audit_init_parent */ + audit_put_parent(parent); + list_add(&krule->rlist, &watch->rules); } @@ -413,6 +421,7 @@ int audit_add_watch(struct audit_krule *krule, struct list_head **list) struct audit_parent *parent; struct path parent_path; int h, ret = 0; + int new = 0; mutex_unlock(&audit_filter_mutex); @@ -433,12 +442,10 @@ int audit_add_watch(struct audit_krule *krule, struct list_head **list) ret = PTR_ERR(parent); goto error; } + new = 1; } - audit_add_to_parent(krule, parent); - - /* match get in audit_find_parent or audit_init_parent */ - audit_put_parent(parent); + audit_add_to_parent(krule, parent, new); h = audit_hash_ino((u32)watch->ino); *list = &audit_inode_hash[h];