From dfd5e3f5fe27bda91d5cc028c86ffbb7a0614489 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 9 Dec 2020 16:06:21 +0100 Subject: [PATCH] locking/lockdep: Mark local_lock_t The local_lock_t's are special, because they cannot form IRQ inversions, make sure we can tell them apart from the rest of the locks. Signed-off-by: Peter Zijlstra (Intel) --- include/linux/local_lock_internal.h | 5 ++++- include/linux/lockdep.h | 15 ++++++++++++--- include/linux/lockdep_types.h | 18 ++++++++++++++---- kernel/locking/lockdep.c | 16 +++++++++------- 4 files changed, 39 insertions(+), 15 deletions(-) diff --git a/include/linux/local_lock_internal.h b/include/linux/local_lock_internal.h index 4a8795b21d77..ded90b097e6e 100644 --- a/include/linux/local_lock_internal.h +++ b/include/linux/local_lock_internal.h @@ -18,6 +18,7 @@ typedef struct { .dep_map = { \ .name = #lockname, \ .wait_type_inner = LD_WAIT_CONFIG, \ + .lock_type = LD_LOCK_PERCPU, \ } #else # define LL_DEP_MAP_INIT(lockname) @@ -30,7 +31,9 @@ do { \ static struct lock_class_key __key; \ \ debug_check_no_locks_freed((void *)lock, sizeof(*lock));\ - lockdep_init_map_wait(&(lock)->dep_map, #lock, &__key, 0, LD_WAIT_CONFIG);\ + lockdep_init_map_type(&(lock)->dep_map, #lock, &__key, 0, \ + LD_WAIT_CONFIG, LD_WAIT_INV, \ + LD_LOCK_PERCPU); \ } while (0) #ifdef CONFIG_DEBUG_LOCK_ALLOC diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index b9e9adec73e8..7b7ebf2e28ec 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -185,12 +185,19 @@ extern void lockdep_unregister_key(struct lock_class_key *key); * to lockdep: */ -extern void lockdep_init_map_waits(struct lockdep_map *lock, const char *name, - struct lock_class_key *key, int subclass, short inner, short outer); +extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name, + struct lock_class_key *key, int subclass, u8 inner, u8 outer, u8 lock_type); + +static inline void +lockdep_init_map_waits(struct lockdep_map *lock, const char *name, + struct lock_class_key *key, int subclass, u8 inner, u8 outer) +{ + lockdep_init_map_type(lock, name, key, subclass, inner, LD_WAIT_INV, LD_LOCK_NORMAL); +} static inline void lockdep_init_map_wait(struct lockdep_map *lock, const char *name, - struct lock_class_key *key, int subclass, short inner) + struct lock_class_key *key, int subclass, u8 inner) { lockdep_init_map_waits(lock, name, key, subclass, inner, LD_WAIT_INV); } @@ -340,6 +347,8 @@ static inline void lockdep_set_selftest_task(struct task_struct *task) # define lock_set_class(l, n, k, s, i) do { } while (0) # define lock_set_subclass(l, s, i) do { } while (0) # define lockdep_init() do { } while (0) +# define lockdep_init_map_type(lock, name, key, sub, inner, outer, type) \ + do { (void)(name); (void)(key); } while (0) # define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \ do { (void)(name); (void)(key); } while (0) # define lockdep_init_map_wait(lock, name, key, sub, inner) \ diff --git a/include/linux/lockdep_types.h b/include/linux/lockdep_types.h index 9a1fd49df17f..2ec9ff5a7fff 100644 --- a/include/linux/lockdep_types.h +++ b/include/linux/lockdep_types.h @@ -30,6 +30,12 @@ enum lockdep_wait_type { LD_WAIT_MAX, /* must be last */ }; +enum lockdep_lock_type { + LD_LOCK_NORMAL = 0, /* normal, catch all */ + LD_LOCK_PERCPU, /* percpu */ + LD_LOCK_MAX, +}; + #ifdef CONFIG_LOCKDEP /* @@ -119,8 +125,10 @@ struct lock_class { int name_version; const char *name; - short wait_type_inner; - short wait_type_outer; + u8 wait_type_inner; + u8 wait_type_outer; + u8 lock_type; + /* u8 hole; */ #ifdef CONFIG_LOCK_STAT unsigned long contention_point[LOCKSTAT_POINTS]; @@ -169,8 +177,10 @@ struct lockdep_map { struct lock_class_key *key; struct lock_class *class_cache[NR_LOCKDEP_CACHING_CLASSES]; const char *name; - short wait_type_outer; /* can be taken in this context */ - short wait_type_inner; /* presents this context */ + u8 wait_type_outer; /* can be taken in this context */ + u8 wait_type_inner; /* presents this context */ + u8 lock_type; + /* u8 hole; */ #ifdef CONFIG_LOCK_STAT int cpu; unsigned long ip; diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index c1418b47f625..b061e2991700 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1290,6 +1290,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) class->name_version = count_matching_names(class); class->wait_type_inner = lock->wait_type_inner; class->wait_type_outer = lock->wait_type_outer; + class->lock_type = lock->lock_type; /* * We use RCU's safe list-add method to make * parallel walking of the hash-list safe: @@ -4503,9 +4504,9 @@ print_lock_invalid_wait_context(struct task_struct *curr, */ static int check_wait_context(struct task_struct *curr, struct held_lock *next) { - short next_inner = hlock_class(next)->wait_type_inner; - short next_outer = hlock_class(next)->wait_type_outer; - short curr_inner; + u8 next_inner = hlock_class(next)->wait_type_inner; + u8 next_outer = hlock_class(next)->wait_type_outer; + u8 curr_inner; int depth; if (!curr->lockdep_depth || !next_inner || next->trylock) @@ -4528,7 +4529,7 @@ static int check_wait_context(struct task_struct *curr, struct held_lock *next) for (; depth < curr->lockdep_depth; depth++) { struct held_lock *prev = curr->held_locks + depth; - short prev_inner = hlock_class(prev)->wait_type_inner; + u8 prev_inner = hlock_class(prev)->wait_type_inner; if (prev_inner) { /* @@ -4577,9 +4578,9 @@ static inline int check_wait_context(struct task_struct *curr, /* * Initialize a lock instance's lock-class mapping info: */ -void lockdep_init_map_waits(struct lockdep_map *lock, const char *name, +void lockdep_init_map_type(struct lockdep_map *lock, const char *name, struct lock_class_key *key, int subclass, - short inner, short outer) + u8 inner, u8 outer, u8 lock_type) { int i; @@ -4602,6 +4603,7 @@ void lockdep_init_map_waits(struct lockdep_map *lock, const char *name, lock->wait_type_outer = outer; lock->wait_type_inner = inner; + lock->lock_type = lock_type; /* * No key, no joy, we need to hash something. @@ -4636,7 +4638,7 @@ void lockdep_init_map_waits(struct lockdep_map *lock, const char *name, raw_local_irq_restore(flags); } } -EXPORT_SYMBOL_GPL(lockdep_init_map_waits); +EXPORT_SYMBOL_GPL(lockdep_init_map_type); struct lock_class_key __lockdep_no_validate__; EXPORT_SYMBOL_GPL(__lockdep_no_validate__);