[PATCH 2/3] lockdep: consolidate by new validate_held_lock()

From: J. R. Okajima
Date: Thu Feb 02 2017 - 11:45:33 EST


A simple consolidataion. The behaviour should not change.

Signed-off-by: J. R. Okajima <hooanon05g@xxxxxxxxx>
---
kernel/locking/lockdep.c | 39 +++++++++++++++++++++------------------
1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index b7a2001..7dc8f8e 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -3464,6 +3464,23 @@ static struct held_lock *find_held_lock(struct task_struct *curr,
return ret;
}

+static int validate_held_lock(struct task_struct *curr, unsigned int depth,
+ int idx)
+{
+ struct held_lock *hlock;
+
+ for (hlock = curr->held_locks + idx; idx < depth; idx++, hlock++)
+ if (!__lock_acquire(hlock->instance,
+ hlock_class(hlock)->subclass,
+ hlock->trylock,
+ hlock->read, hlock->check,
+ hlock->hardirqs_off,
+ hlock->nest_lock, hlock->acquire_ip,
+ hlock->references, hlock->pin_count))
+ return 1;
+ return 0;
+}
+
static int
__lock_set_class(struct lockdep_map *lock, const char *name,
struct lock_class_key *key, unsigned int subclass,
@@ -3494,15 +3511,8 @@ __lock_set_class(struct lockdep_map *lock, const char *name,
curr->lockdep_depth = i;
curr->curr_chain_key = hlock->prev_chain_key;

- for (; i < depth; i++) {
- hlock = curr->held_locks + i;
- if (!__lock_acquire(hlock->instance,
- hlock_class(hlock)->subclass, hlock->trylock,
- hlock->read, hlock->check, hlock->hardirqs_off,
- hlock->nest_lock, hlock->acquire_ip,
- hlock->references, hlock->pin_count))
- return 0;
- }
+ if (validate_held_lock(curr, depth, i))
+ return 0;

/*
* I took it apart and put it back together again, except now I have
@@ -3573,15 +3583,8 @@ __lock_release(struct lockdep_map *lock, int nested, unsigned long ip)
curr->lockdep_depth = i;
curr->curr_chain_key = hlock->prev_chain_key;

- for (i++; i < depth; i++) {
- hlock = curr->held_locks + i;
- if (!__lock_acquire(hlock->instance,
- hlock_class(hlock)->subclass, hlock->trylock,
- hlock->read, hlock->check, hlock->hardirqs_off,
- hlock->nest_lock, hlock->acquire_ip,
- hlock->references, hlock->pin_count))
- return 0;
- }
+ if (validate_held_lock(curr, depth, i + 1))
+ return 0;

/*
* We had N bottles of beer on the wall, we drank one, but now
--
2.1.4