tree bbd92afe1437ac77084c6ba3485f7f5a988dd673
parent 898552c9d807fe59f3ecaf9c300c109358375c12
author Jarek Poplawski <jarkao2@o2.pl> 1171100698 -0800
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1171219886 -0800

[PATCH] lockdep: more unlock-on-error fixes

- returns after DEBUG_LOCKS_WARN_ON added in 3 places

- debug_locks checking after lookup_chain_cache() added in
  __lock_acquire()

- locking for testing and changing global variable max_lockdep_depth
  added in __lock_acquire()

From: Ingo Molnar <mingo@elte.hu>

My __acquire_lock() cleanup introduced a locking bug: on SMP systems we'd
release a non-owned graph lock.  Fix this by moving the graph unlock back,
and by leaving the max_lockdep_depth variable update possibly racy.  (we
dont care, it's just statistics)

Also add some minimal debugging code to graph_unlock()/graph_lock(),
which caught this locking bug.

Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>