diff options
author | Byungchul Park <byungchul.park@lge.com> | 2017-08-07 16:12:50 +0900 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2017-08-10 12:29:06 +0200 |
commit | 70911fdc9576f4eeb3986689a1c9a778a4a4aacb (patch) | |
tree | baebf222c9089599a6df844ad01a2840c7cf07cf /kernel/locking | |
parent | 49347a986ab45eb1dafbf25170647c890f8ff192 (diff) |
locking/lockdep: Change the meaning of check_prev_add()'s return value
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.park@lge.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: boqun.feng@gmail.com
Cc: kernel-team@lge.com
Cc: kirill@shutemov.name
Cc: npiggin@gmail.com
Cc: walken@google.com
Cc: willy@infradead.org
Link: http://lkml.kernel.org/r/1502089981-21272-4-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/locking')
-rw-r--r-- | kernel/locking/lockdep.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index bdf6b31f702b..7cf02fab1725 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1881,7 +1881,7 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, if (entry->class == hlock_class(next)) { if (distance == 1) entry->distance = 1; - return 2; + return 1; } } @@ -1935,9 +1935,10 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, print_lock_name(hlock_class(next)); printk(KERN_CONT "\n"); dump_stack(); - return graph_lock(); + if (!graph_lock()) + return 0; } - return 1; + return 2; } /* |