From fe27b0de8dfcdf8482558ce5d25e697fe74d851e Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 6 Dec 2018 17:11:37 -0800 Subject: [PATCH] locking/lockdep: Stop using RCU primitives to access 'all_lock_classes' Due to the previous patch all code that accesses the 'all_lock_classes' list holds the graph lock. Hence use regular list primitives instead of their RCU variants to access this list. Signed-off-by: Bart Van Assche Signed-off-by: Peter Zijlstra (Intel) Cc: Johannes Berg Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Sasha Levin Cc: Thomas Gleixner Cc: Waiman Long Cc: johannes.berg@intel.com Cc: tj@kernel.org Link: https://lkml.kernel.org/r/20181207011148.251812-14-bvanassche@acm.org Signed-off-by: Ingo Molnar --- kernel/locking/lockdep.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 737d2dd..5c837a5 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -629,7 +629,8 @@ static int static_obj(void *obj) /* * To make lock name printouts unique, we calculate a unique - * class->name_version generation counter: + * class->name_version generation counter. The caller must hold the graph + * lock. */ static int count_matching_names(struct lock_class *new_class) { @@ -639,7 +640,7 @@ static int count_matching_names(struct lock_class *new_class) if (!new_class->name) return 0; - list_for_each_entry_rcu(class, &all_lock_classes, lock_entry) { + list_for_each_entry(class, &all_lock_classes, lock_entry) { if (new_class->key - new_class->subclass == class->key) return class->name_version; if (class->name && !strcmp(class->name, new_class->name)) @@ -803,7 +804,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) /* * Add it to the global list of classes: */ - list_add_tail_rcu(&class->lock_entry, &all_lock_classes); + list_add_tail(&class->lock_entry, &all_lock_classes); if (verbose(class)) { graph_unlock(); @@ -4141,7 +4142,7 @@ static void zap_class(struct lock_class *class) * Unhash the class and remove it from the all_lock_classes list: */ hlist_del_rcu(&class->hash_entry); - list_del_rcu(&class->lock_entry); + list_del(&class->lock_entry); RCU_INIT_POINTER(class->key, NULL); RCU_INIT_POINTER(class->name, NULL); -- 2.7.4