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| author | Ingo Molnar <mingo@kernel.org> | 2016-02-09 12:03:15 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-02-09 12:03:15 +0100 |
| commit | 3aa6b46c6d6d0f89395ec3811a77fe22e57fa0d3 (patch) | |
| tree | 12f0563b9b4915ad1b43488df21709dfac287f37 /kernel | |
| parent | 975db45e9cc561bf8a7eddfa0705d3a078ec184f (diff) | |
| parent | 8a5fd56431fe1682e870bd6ab0c276e74befbeb9 (diff) | |
| download | blackbird-op-linux-3aa6b46c6d6d0f89395ec3811a77fe22e57fa0d3.tar.gz blackbird-op-linux-3aa6b46c6d6d0f89395ec3811a77fe22e57fa0d3.zip | |
Merge branch 'locking/urgent' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/locking/lockdep.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 60ace56618f6..c7710e4092ef 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1822,7 +1822,7 @@ 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, int distance, int trylock_loop) + struct held_lock *next, int distance, int *stack_saved) { struct lock_list *entry; int ret; @@ -1883,8 +1883,11 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, } } - if (!trylock_loop && !save_trace(&trace)) - return 0; + if (!*stack_saved) { + if (!save_trace(&trace)) + return 0; + *stack_saved = 1; + } /* * Ok, all validations passed, add the new lock @@ -1907,6 +1910,8 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, * Debugging printouts: */ if (verbose(hlock_class(prev)) || verbose(hlock_class(next))) { + /* We drop graph lock, so another thread can overwrite trace. */ + *stack_saved = 0; graph_unlock(); printk("\n new dependency: "); print_lock_name(hlock_class(prev)); @@ -1929,7 +1934,7 @@ static int check_prevs_add(struct task_struct *curr, struct held_lock *next) { int depth = curr->lockdep_depth; - int trylock_loop = 0; + int stack_saved = 0; struct held_lock *hlock; /* @@ -1956,7 +1961,7 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next) */ if (hlock->read != 2 && hlock->check) { if (!check_prev_add(curr, hlock, next, - distance, trylock_loop)) + distance, &stack_saved)) return 0; /* * Stop after the first non-trylock entry, @@ -1979,7 +1984,6 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next) if (curr->held_locks[depth].irq_context != curr->held_locks[depth-1].irq_context) break; - trylock_loop = 1; } return 1; out_bug: |
