Dept should work independently from Lockdep. However, there's no choise but to rely on Lockdep code and its instances for now.
Signed-off-by: Byungchul Park byungchul.park@lge.com --- include/linux/lockdep.h | 72 ++++++++++++++++++++++++++++++++++++++++--- include/linux/lockdep_types.h | 3 ++ kernel/locking/lockdep.c | 12 ++++---- 3 files changed, 77 insertions(+), 10 deletions(-)
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 467b942..2aab445 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -20,6 +20,33 @@ extern int prove_locking; extern int lock_stat;
+#ifdef CONFIG_DEPT +static inline void dept_after_copy_map(struct dept_map *to, + struct dept_map *from) +{ + int i; + + if (from->keys == &from->keys_local) + to->keys = &to->keys_local; + + if (!to->keys) + return; + + /* + * Since the class cache can be modified concurrently we could observe + * half pointers (64bit arch using 32bit copy insns). Therefore clear + * the caches and take the performance hit. + * + * XXX it doesn't work well with lockdep_set_class_and_subclass(), since + * that relies on cache abuse. + */ + for (i = 0; i < DEPT_MAX_SUBCLASSES_CACHE; i++) + to->keys->classes[i] = NULL; +} +#else +#define dept_after_copy_map(t, f) do { } while (0) +#endif + #ifdef CONFIG_LOCKDEP
#include <linux/linkage.h> @@ -43,6 +70,8 @@ static inline void lockdep_copy_map(struct lockdep_map *to, */ for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++) to->class_cache[i] = NULL; + + dept_after_copy_map(&to->dmap, &from->dmap); }
/* @@ -176,8 +205,19 @@ struct held_lock { current->lockdep_recursion -= LOCKDEP_OFF; \ } while (0)
-extern void lockdep_register_key(struct lock_class_key *key); -extern void lockdep_unregister_key(struct lock_class_key *key); +extern void __lockdep_register_key(struct lock_class_key *key); +extern void __lockdep_unregister_key(struct lock_class_key *key); + +#define lockdep_register_key(k) \ +do { \ + __lockdep_register_key(k); \ + dept_key_init(&(k)->dkey); \ +} while (0) +#define lockdep_unregister_key(k) \ +do { \ + __lockdep_unregister_key(k); \ + dept_key_destroy(&(k)->dkey); \ +} while (0)
/* * These methods are used by specific locking variants (spinlocks, @@ -185,9 +225,18 @@ struct held_lock { * to lockdep: */
-extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name, +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);
+#define lockdep_init_map_type(l, n, k, s, i, o, t) \ +do { \ + __lockdep_init_map_type(l, n, k, s, i, o, t); \ + if ((k) == &__lockdep_no_validate__) \ + dept_map_nocheck(&(l)->dmap); \ + else \ + dept_map_init(&(l)->dmap, &(k)->dkey, s, n); \ +} while (0) + 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) @@ -431,13 +480,28 @@ enum xhlock_context_t { XHLOCK_CTX_NR, };
+#ifdef CONFIG_DEPT +/* + * TODO: I found the case to use an address of other than a real key as + * _key, for instance, in workqueue. So for now, we cannot use the + * assignment like '.dmap.keys = &(_key)->dkey' unless it's fixed. + */ +#define STATIC_DEPT_MAP_INIT(_name, _key) .dmap = { \ + .name = (_name), \ + .keys = NULL, \ + }, +#else +#define STATIC_DEPT_MAP_INIT(_name, _key) +#endif + #define lockdep_init_map_crosslock(m, n, k, s) do {} while (0) /* * To initialize a lockdep_map statically use this macro. * Note that _name must not be NULL. */ #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \ - { .name = (_name), .key = (void *)(_key), } + { .name = (_name), .key = (void *)(_key), \ + STATIC_DEPT_MAP_INIT(_name, _key) }
static inline void lockdep_invariant_state(bool force) {} static inline void lockdep_free_task(struct task_struct *task) {} diff --git a/include/linux/lockdep_types.h b/include/linux/lockdep_types.h index d224308..50c8879 100644 --- a/include/linux/lockdep_types.h +++ b/include/linux/lockdep_types.h @@ -11,6 +11,7 @@ #define __LINUX_LOCKDEP_TYPES_H
#include <linux/types.h> +#include <linux/dept.h>
#define MAX_LOCKDEP_SUBCLASSES 8UL
@@ -76,6 +77,7 @@ struct lock_class_key { struct hlist_node hash_entry; struct lockdep_subclass_key subkeys[MAX_LOCKDEP_SUBCLASSES]; }; + struct dept_key dkey; };
extern struct lock_class_key __lockdep_no_validate__; @@ -185,6 +187,7 @@ struct lockdep_map { int cpu; unsigned long ip; #endif + struct dept_map dmap; };
struct pin_cookie { unsigned int val; }; diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index f8a0212..e324d61 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1184,7 +1184,7 @@ static inline struct hlist_head *keyhashentry(const struct lock_class_key *key) }
/* Register a dynamically allocated key. */ -void lockdep_register_key(struct lock_class_key *key) +void __lockdep_register_key(struct lock_class_key *key) { struct hlist_head *hash_head; struct lock_class_key *k; @@ -1207,7 +1207,7 @@ void lockdep_register_key(struct lock_class_key *key) restore_irqs: raw_local_irq_restore(flags); } -EXPORT_SYMBOL_GPL(lockdep_register_key); +EXPORT_SYMBOL_GPL(__lockdep_register_key);
/* Check whether a key has been registered as a dynamic key. */ static bool is_dynamic_key(const struct lock_class_key *key) @@ -4771,7 +4771,7 @@ static inline int check_wait_context(struct task_struct *curr, /* * Initialize a lock instance's lock-class mapping info: */ -void lockdep_init_map_type(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, u8 inner, u8 outer, u8 lock_type) { @@ -4831,7 +4831,7 @@ void lockdep_init_map_type(struct lockdep_map *lock, const char *name, raw_local_irq_restore(flags); } } -EXPORT_SYMBOL_GPL(lockdep_init_map_type); +EXPORT_SYMBOL_GPL(__lockdep_init_map_type);
struct lock_class_key __lockdep_no_validate__; EXPORT_SYMBOL_GPL(__lockdep_no_validate__); @@ -6291,7 +6291,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) }
/* Unregister a dynamically allocated key. */ -void lockdep_unregister_key(struct lock_class_key *key) +void __lockdep_unregister_key(struct lock_class_key *key) { struct hlist_head *hash_head = keyhashentry(key); struct lock_class_key *k; @@ -6326,7 +6326,7 @@ void lockdep_unregister_key(struct lock_class_key *key) /* Wait until is_dynamic_key() has finished accessing k->hash_entry. */ synchronize_rcu(); } -EXPORT_SYMBOL_GPL(lockdep_unregister_key); +EXPORT_SYMBOL_GPL(__lockdep_unregister_key);
void __init lockdep_init(void) {