diff options
| author | Kent Overstreet <kent.overstreet@gmail.com> | 2021-07-10 22:46:17 -0400 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2022-10-03 17:01:17 -0400 |
| commit | ced7d93920397952d2ed496efb2a46f0b53ff4ed (patch) | |
| tree | acd08a2c798b69322d5b7eba68ee290dd60f65f6 | |
| parent | ccbc4e1a399470ef18741c6f97d963ea8fef45b0 (diff) | |
locking/lockdep: lock_class_is_held()
This patch adds lock_class_is_held(), which can be used to verify that a
particular type of lock is _not_ held.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
| -rw-r--r-- | include/linux/lockdep.h | 4 | ||||
| -rw-r--r-- | kernel/locking/lockdep.c | 20 |
2 files changed, 24 insertions, 0 deletions
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 1f1099dac3f0..e027c504b7d3 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -339,6 +339,8 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie); #define lockdep_repin_lock(l,c) lock_repin_lock(&(l)->dep_map, (c)) #define lockdep_unpin_lock(l,c) lock_unpin_lock(&(l)->dep_map, (c)) +int lock_class_is_held(struct lock_class_key *key); + #else /* !CONFIG_LOCKDEP */ static inline void lockdep_init_task(struct task_struct *task) @@ -427,6 +429,8 @@ extern int lockdep_is_held(const void *); #define lockdep_repin_lock(l, c) do { (void)(l); (void)(c); } while (0) #define lockdep_unpin_lock(l, c) do { (void)(l); (void)(c); } while (0) +static inline int lock_class_is_held(struct lock_class_key *key) { return 0; } + #endif /* !LOCKDEP */ enum xhlock_context_t { diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 64a13eb56078..fe2cebd7651e 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -6484,6 +6484,26 @@ void debug_check_no_locks_held(void) } EXPORT_SYMBOL_GPL(debug_check_no_locks_held); +#ifdef CONFIG_LOCKDEP +int lock_class_is_held(struct lock_class_key *key) +{ + struct task_struct *curr = current; + struct held_lock *hlock; + + if (unlikely(!debug_locks)) + return 0; + + for (hlock = curr->held_locks; + hlock < curr->held_locks + curr->lockdep_depth; + hlock++) + if (hlock->instance->key == key) + return 1; + + return 0; +} +EXPORT_SYMBOL_GPL(lock_class_is_held); +#endif + #ifdef __KERNEL__ void debug_show_all_locks(void) { |