diff options
| author | Liam R. Howlett <Liam.Howlett@oracle.com> | 2023-07-14 15:55:51 -0400 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-18 10:12:40 -0700 |
| commit | 19a462f06eb5a78e0c3ebe4fd4fbdc71620b8788 (patch) | |
| tree | d3de1776e5a6a170d97ebecf6aa421ff73202a23 /lib | |
| parent | 02fdb25fb41c563a3afbd4a97469c527a6c5abbf (diff) | |
maple_tree: Be more strict about locking
Use lockdep to check the write path in the maple tree holds the lock in
write mode.
Introduce mt_write_lock_is_held() to check if the lock is held for
writing. Update the necessary checks for rcu_dereference_protected() to
use the new write lock check.
Link: https://lkml.kernel.org/r/20230714195551.894800-5-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oliver Sang <oliver.sang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/maple_tree.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/lib/maple_tree.c b/lib/maple_tree.c index b6b3973897f0..3b6f8c8dac65 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -777,6 +777,12 @@ static inline void __rcu **ma_slots(struct maple_node *mn, enum maple_type mt) } } +static inline bool mt_write_locked(const struct maple_tree *mt) +{ + return mt_external_lock(mt) ? mt_write_lock_is_held(mt) : + lockdep_is_held(&mt->ma_lock); +} + static inline bool mt_locked(const struct maple_tree *mt) { return mt_external_lock(mt) ? mt_lock_is_held(mt) : @@ -792,7 +798,7 @@ static inline void *mt_slot(const struct maple_tree *mt, static inline void *mt_slot_locked(struct maple_tree *mt, void __rcu **slots, unsigned char offset) { - return rcu_dereference_protected(slots[offset], mt_locked(mt)); + return rcu_dereference_protected(slots[offset], mt_write_locked(mt)); } /* * mas_slot_locked() - Get the slot value when holding the maple tree lock. @@ -835,7 +841,7 @@ static inline void *mas_root(struct ma_state *mas) static inline void *mt_root_locked(struct maple_tree *mt) { - return rcu_dereference_protected(mt->ma_root, mt_locked(mt)); + return rcu_dereference_protected(mt->ma_root, mt_write_locked(mt)); } /* |