Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 956f3563 authored by Bart Van Assche's avatar Bart Van Assche Committed by Ingo Molnar
Browse files

locking/lockdep: Split lockdep_free_key_range() and lockdep_reset_lock() 



This patch does not change the behavior of these functions but makes the
patch that frees unused lock classes easier to read.

Signed-off-by: default avatarBart Van Assche <bvanassche@acm.org>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20190214230058.196511-9-bvanassche@acm.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent feb0a386

kernel/locking/lockdep.c

+36 −36
Original line number Diff line number Diff line
@@ -4160,6 +4160,24 @@ static inline int within(const void *addr, void *start, unsigned long size) 
	return addr >= start && addr < start + size;

}



static void __lockdep_free_key_range(void *start, unsigned long size)

{

	struct lock_class *class;

	struct hlist_head *head;

	int i;



	/* Unhash all classes that were created by a module. */

	for (i = 0; i < CLASSHASH_SIZE; i++) {

		head = classhash_table + i;

		hlist_for_each_entry_rcu(class, head, hash_entry) {

			if (!within(class->key, start, size) &&

			    !within(class->name, start, size))

				continue;

			zap_class(class);

		}

	}

}



/*

 * Used in module.c to remove lock classes from memory that is going to be

 * freed; and possibly re-used by other modules.
@@ -4170,30 +4188,14 @@ static inline int within(const void *addr, void *start, unsigned long size) 
 */

void lockdep_free_key_range(void *start, unsigned long size)

{

	struct lock_class *class;

	struct hlist_head *head;

	unsigned long flags;

	int i;

	int locked;



	init_data_structures_once();



	raw_local_irq_save(flags);

	locked = graph_lock();



	/*

	 * Unhash all classes that were created by this module:

	 */

	for (i = 0; i < CLASSHASH_SIZE; i++) {

		head = classhash_table + i;

		hlist_for_each_entry_rcu(class, head, hash_entry) {

			if (within(class->key, start, size))

				zap_class(class);

			else if (within(class->name, start, size))

				zap_class(class);

		}

	}



	__lockdep_free_key_range(start, size);

	if (locked)

		graph_unlock();

	raw_local_irq_restore(flags);
@@ -4235,16 +4237,11 @@ static bool lock_class_cache_is_registered(struct lockdep_map *lock) 
	return false;

}



void lockdep_reset_lock(struct lockdep_map *lock)

/* The caller must hold the graph lock. Does not sleep. */

static void __lockdep_reset_lock(struct lockdep_map *lock)

{

	struct lock_class *class;

	unsigned long flags;

	int j, locked;



	init_data_structures_once();



	raw_local_irq_save(flags);

	locked = graph_lock();

	int j;



	/*

	 * Remove all classes this lock might have:
@@ -4261,19 +4258,22 @@ void lockdep_reset_lock(struct lockdep_map *lock) 
	 * Debug check: in the end all mapped classes should

	 * be gone.

	 */

	if (unlikely(lock_class_cache_is_registered(lock))) {

		if (debug_locks_off_graph_unlock()) {

			/*

			 * We all just reset everything, how did it match?

			 */

			WARN_ON(1);

		}

		goto out_restore;

	if (WARN_ON_ONCE(lock_class_cache_is_registered(lock)))

		debug_locks_off();

}



void lockdep_reset_lock(struct lockdep_map *lock)

{

	unsigned long flags;

	int locked;



	init_data_structures_once();



	raw_local_irq_save(flags);

	locked = graph_lock();

	__lockdep_reset_lock(lock);

	if (locked)

		graph_unlock();



out_restore:

	raw_local_irq_restore(flags);

}