From 1a616c2fe96b357894b74b41787d4ea6987f6199 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Thu, 21 Dec 2023 20:34:17 -0500 Subject: 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 Cc: Ingo Molnar Cc: Will Deacon Cc: Waiman Long Cc: Boqun Feng Signed-off-by: Kent Overstreet --- include/linux/lockdep.h | 4 ++++ include/linux/lockdep_types.h | 1 + 2 files changed, 5 insertions(+) (limited to 'include/linux') 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; -- cgit v1.3 From a97b43fac5b9b3ffca71b8a917a249789902fce9 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Thu, 18 Jul 2024 17:17:10 -0400 Subject: lockdep: Add comments for lockdep_set_no{validate,track}_class() Cc: Waiman Long Signed-off-by: Kent Overstreet --- include/linux/lockdep.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/linux') diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index b76f1bcd2f7f..0759e30df392 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -178,9 +178,24 @@ static inline void lockdep_init_map(struct lockdep_map *lock, const char *name, (lock)->dep_map.wait_type_outer, \ (lock)->dep_map.lock_type) +/** + * lockdep_set_novalidate_class: disable checking of lock ordering on a given + * lock + * @lock: Lock to mark + * + * Lockdep will still record that this lock has been taken, and print held + * instances when dumping locks + */ #define lockdep_set_novalidate_class(lock) \ lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock) +/** + * lockdep_set_notrack_class: disable lockdep tracking of a given lock entirely + * @lock: Lock to mark + * + * Bigger hammer than lockdep_set_novalidate_class: so far just for bcachefs, + * which takes more locks than lockdep is able to track (48). + */ #define lockdep_set_notrack_class(lock) \ lockdep_set_class_and_name(lock, &__lockdep_no_track__, #lock) -- cgit v1.3