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Diffstat (limited to 'kernel/lockdep.c')
-rw-r--r--kernel/lockdep.c19
1 files changed, 12 insertions, 7 deletions
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 2d616f4d853..592c576d77a 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -490,7 +490,7 @@ static void print_lock_dependencies(struct lock_class *class, int depth)
* Add a new dependency to the head of the list:
*/
static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
- struct list_head *head, unsigned long ip)
+ struct list_head *head, unsigned long ip, int distance)
{
struct lock_list *entry;
/*
@@ -502,6 +502,7 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
return 0;
entry->class = this;
+ entry->distance = distance;
if (!save_trace(&entry->trace))
return 0;
@@ -906,7 +907,7 @@ check_deadlock(struct task_struct *curr, struct held_lock *next,
*/
static int
check_prev_add(struct task_struct *curr, struct held_lock *prev,
- struct held_lock *next)
+ struct held_lock *next, int distance)
{
struct lock_list *entry;
int ret;
@@ -984,8 +985,11 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
* L2 added to its dependency list, due to the first chain.)
*/
list_for_each_entry(entry, &prev->class->locks_after, entry) {
- if (entry->class == next->class)
+ if (entry->class == next->class) {
+ if (distance == 1)
+ entry->distance = 1;
return 2;
+ }
}
/*
@@ -993,12 +997,13 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
* to the previous lock's dependency list:
*/
ret = add_lock_to_list(prev->class, next->class,
- &prev->class->locks_after, next->acquire_ip);
+ &prev->class->locks_after, next->acquire_ip, distance);
+
if (!ret)
return 0;
ret = add_lock_to_list(next->class, prev->class,
- &next->class->locks_before, next->acquire_ip);
+ &next->class->locks_before, next->acquire_ip, distance);
if (!ret)
return 0;
@@ -1046,13 +1051,14 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
goto out_bug;
for (;;) {
+ int distance = curr->lockdep_depth - depth + 1;
hlock = curr->held_locks + depth-1;
/*
* Only non-recursive-read entries get new dependencies
* added:
*/
if (hlock->read != 2) {
- if (!check_prev_add(curr, hlock, next))
+ if (!check_prev_add(curr, hlock, next, distance))
return 0;
/*
* Stop after the first non-trylock entry,
@@ -2779,4 +2785,3 @@ void debug_show_held_locks(struct task_struct *task)
}
EXPORT_SYMBOL_GPL(debug_show_held_locks);
-