Commit 627f364d authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Ingo Molnar
Browse files

locking/lockdep: Use expanded masks on find_usage_*() functions 



In order to optimize check_irq_usage() and factorize all the IRQ usage
validations we'll need to be able to check multiple lock usage bits at
once. Prepare the low level usage mask check functions for that purpose.

Signed-off-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
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: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20190402160244.32434-4-frederic@kernel.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent c902a1e8

kernel/locking/lockdep.c

+10 −10
Original line number Diff line number Diff line
@@ -1682,9 +1682,9 @@ check_redundant(struct lock_list *root, struct lock_class *target, 
 * without creating any illegal irq-safe -> irq-unsafe lock dependency.

 */



static inline int usage_match(struct lock_list *entry, void *bit)

static inline int usage_match(struct lock_list *entry, void *mask)

{

	return entry->class->usage_mask & (1 << (enum lock_usage_bit)bit);

	return entry->class->usage_mask & *(unsigned long *)mask;

}
@@ -1700,14 +1700,14 @@ static inline int usage_match(struct lock_list *entry, void *bit) 
 * Return <0 on error.

 */

static int

find_usage_forwards(struct lock_list *root, enum lock_usage_bit bit,

find_usage_forwards(struct lock_list *root, unsigned long usage_mask,

			struct lock_list **target_entry)

{

	int result;



	debug_atomic_inc(nr_find_usage_forwards_checks);



	result = __bfs_forwards(root, (void *)bit, usage_match, target_entry);

	result = __bfs_forwards(root, &usage_mask, usage_match, target_entry);



	return result;

}
@@ -1723,14 +1723,14 @@ find_usage_forwards(struct lock_list *root, enum lock_usage_bit bit, 
 * Return <0 on error.

 */

static int

find_usage_backwards(struct lock_list *root, enum lock_usage_bit bit,

find_usage_backwards(struct lock_list *root, unsigned long usage_mask,

			struct lock_list **target_entry)

{

	int result;



	debug_atomic_inc(nr_find_usage_backwards_checks);



	result = __bfs_backwards(root, (void *)bit, usage_match, target_entry);

	result = __bfs_backwards(root, &usage_mask, usage_match, target_entry);



	return result;

}
@@ -1935,7 +1935,7 @@ check_usage(struct task_struct *curr, struct held_lock *prev, 
	this.parent = NULL;



	this.class = hlock_class(prev);

	ret = find_usage_backwards(&this, bit_backwards, &target_entry);

	ret = find_usage_backwards(&this, lock_flag(bit_backwards), &target_entry);

	if (ret < 0)

		return print_bfs_bug(ret);

	if (ret == 1)
@@ -1943,7 +1943,7 @@ check_usage(struct task_struct *curr, struct held_lock *prev, 


	that.parent = NULL;

	that.class = hlock_class(next);

	ret = find_usage_forwards(&that, bit_forwards, &target_entry1);

	ret = find_usage_forwards(&that, lock_flag(bit_forwards), &target_entry1);

	if (ret < 0)

		return print_bfs_bug(ret);

	if (ret == 1)
@@ -2941,7 +2941,7 @@ check_usage_forwards(struct task_struct *curr, struct held_lock *this, 


	root.parent = NULL;

	root.class = hlock_class(this);

	ret = find_usage_forwards(&root, bit, &target_entry);

	ret = find_usage_forwards(&root, lock_flag(bit), &target_entry);

	if (ret < 0)

		return print_bfs_bug(ret);

	if (ret == 1)
@@ -2965,7 +2965,7 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this, 


	root.parent = NULL;

	root.class = hlock_class(this);

	ret = find_usage_backwards(&root, bit, &target_entry);

	ret = find_usage_backwards(&root, lock_flag(bit), &target_entry);

	if (ret < 0)

		return print_bfs_bug(ret);

	if (ret == 1)

CRA Git | Maintained and supported by SUSTech CRA and CCSE