diff options
| author | Kent Overstreet <kent.overstreet@linux.dev> | 2023-12-21 20:34:17 -0500 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2024-07-14 19:00:16 -0400 |
| commit | 1a616c2fe96b357894b74b41787d4ea6987f6199 (patch) | |
| tree | f14fa2ca62aa960c73794f45945b44c73cfc8f63 | |
| parent | 8f523d425e0255a68d2f47f9b21db4f684c185c9 (diff) | |
lockdep: lockdep_set_notrack_class()
Add a new helper to disable lockdep tracking entirely for a given class.
This is needed for bcachefs, which takes too many btree node locks for
lockdep to track. Instead, we have a single lockdep_map for "btree_trans
has any btree nodes locked", which makes more since given that we have
centralized lock management and a cycle detector.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
| -rw-r--r-- | fs/bcachefs/btree_locking.c | 2 | ||||
| -rw-r--r-- | include/linux/lockdep.h | 4 | ||||
| -rw-r--r-- | include/linux/lockdep_types.h | 1 | ||||
| -rw-r--r-- | kernel/locking/lockdep.c | 9 |
4 files changed, 14 insertions, 2 deletions
diff --git a/fs/bcachefs/btree_locking.c b/fs/bcachefs/btree_locking.c index c51826fd557f..8bdfe573e95b 100644 --- a/fs/bcachefs/btree_locking.c +++ b/fs/bcachefs/btree_locking.c @@ -10,7 +10,7 @@ void bch2_btree_lock_init(struct btree_bkey_cached_common *b, enum six_lock_init_flags flags) { __six_lock_init(&b->lock, "b->c.lock", &bch2_btree_node_lock_key, flags); - lockdep_set_novalidate_class(&b->lock); + lockdep_set_notrack_class(&b->lock); } #ifdef CONFIG_LOCKDEP diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 08b0d1d9d78b..b76f1bcd2f7f 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -181,6 +181,9 @@ static inline void lockdep_init_map(struct lockdep_map *lock, const char *name, #define lockdep_set_novalidate_class(lock) \ lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock) +#define lockdep_set_notrack_class(lock) \ + lockdep_set_class_and_name(lock, &__lockdep_no_track__, #lock) + /* * Compare locking classes */ @@ -338,6 +341,7 @@ static inline void lockdep_set_selftest_task(struct task_struct *task) #define lockdep_set_subclass(lock, sub) do { } while (0) #define lockdep_set_novalidate_class(lock) do { } while (0) +#define lockdep_set_notrack_class(lock) do { } while (0) /* * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP diff --git a/include/linux/lockdep_types.h b/include/linux/lockdep_types.h index 70d30d40ea4a..9f361d3ab9d9 100644 --- a/include/linux/lockdep_types.h +++ b/include/linux/lockdep_types.h @@ -80,6 +80,7 @@ struct lock_class_key { }; extern struct lock_class_key __lockdep_no_validate__; +extern struct lock_class_key __lockdep_no_track__; struct lock_trace; diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 151bd3de5936..b6bb9fcd992a 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -4918,6 +4918,9 @@ EXPORT_SYMBOL_GPL(lockdep_init_map_type); struct lock_class_key __lockdep_no_validate__; EXPORT_SYMBOL_GPL(__lockdep_no_validate__); +struct lock_class_key __lockdep_no_track__; +EXPORT_SYMBOL_GPL(__lockdep_no_track__); + #ifdef CONFIG_PROVE_LOCKING void lockdep_set_lock_cmp_fn(struct lockdep_map *lock, lock_cmp_fn cmp_fn, lock_print_fn print_fn) @@ -5002,6 +5005,9 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, if (unlikely(!debug_locks)) return 0; + if (unlikely(lock->key == &__lockdep_no_track__)) + return 0; + if (!prove_locking || lock->key == &__lockdep_no_validate__) check = 0; @@ -5764,7 +5770,8 @@ void lock_release(struct lockdep_map *lock, unsigned long ip) trace_lock_release(lock, ip); - if (unlikely(!lockdep_enabled())) + if (unlikely(!lockdep_enabled() || + lock->key == &__lockdep_no_track__)) return; raw_local_irq_save(flags); |