[PATCH v7 03/16] lockdep: Change the meaning of check_prev_add()'s return value

[Byungchul Park]

Firstly, return 1 instead of 2 when 'prev -> next' dependency already
exists. Since the value 2 is not referenced anywhere, just return 1
indicating success in this case.

Secondly, return 2 instead of 1 when successfully added a lock_list
entry with saving stack_trace. With that, a caller can decide whether
to avoid redundant save_trace() on the caller site.

Signed-off-by: Byungchul Park <byungchul.p...@lge.com>
---
 kernel/locking/lockdep.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index eb39474..4709110 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1854,7 +1854,7 @@ static inline void inc_chains(void)
                if (entry->class == hlock_class(next)) {
                        if (distance == 1)
                                entry->distance = 1;
-                       return 2;
+                       return 1;
                }
        }
 
@@ -1894,9 +1894,10 @@ static inline void inc_chains(void)
                print_lock_name(hlock_class(next));
                printk(KERN_CONT "\n");
                dump_stack();
-               return graph_lock();
+               if (!graph_lock())
+                       return 0;
        }
-       return 1;
+       return 2;
 }
 
 /*
-- 
1.9.1