lockdep: Save the size of lock_list

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>

include/linux/lockdep.h

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 68cbe7e..f761f0c 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -191,11 +191,11 @@ struct lock_list {
 	struct list_head		entry;
 	struct lock_class		*class;
 	struct stack_trace		trace;
-	int				distance;
+	u16				distance;
 	/* bitmap of different dependencies from head to this */
-	u16				dep;
+	u8				dep;
 	/* used by BFS to record whether this is picked as a recursive read */
-	u16				is_rr;
+	bool				is_rr;
 
 	/*
 	 * The parent field is used to implement breadth-first search, and the

kernel/locking/lockdep.c

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 1c209b0..dc646f4 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -886,7 +886,7 @@ static struct lock_list *alloc_list_entry(void)
  * Add a new dependency to the head of the list:
  */
 static int add_lock_to_list(struct lock_class *this, struct list_head *head,
-			    unsigned long ip, int distance, unsigned int dep,
+			    unsigned long ip, u16 distance, unsigned int dep,
 			    struct stack_trace *trace)
 {
 	struct lock_list *entry;
@@ -1075,7 +1075,7 @@ static inline unsigned int calc_dep(int prev, int next)
  * N: non-recursive lock
  * R: recursive read lock
  */
-static inline int pick_dep(u16 is_rr, u16 cap_dep)
+static inline int pick_dep(bool is_rr, u8 cap_dep)
 {
 	if (is_rr) { /* could only pick N --> */
 		if (cap_dep & DEP_NN_MASK)
@@ -1125,7 +1125,8 @@ static enum bfs_result __bfs(struct lock_list *source_entry,
 	struct list_head *head;
 	struct circular_queue *cq = &lock_cq;
 	enum bfs_result ret = BFS_RNOMATCH;
-	int is_rr, next_is_rr;
+	bool is_rr;
+	int next_is_rr;
 
 	if (match(source_entry, data)) {
 		*target_entry = source_entry;
@@ -1181,7 +1182,7 @@ static enum bfs_result __bfs(struct lock_list *source_entry,
 			next_is_rr = pick_dep(is_rr, entry->dep);
 			if (next_is_rr < 0)
 				continue;
-			entry->is_rr = next_is_rr;
+			entry->is_rr = !!next_is_rr;
 
 			visit_lock_entry(entry, lock);
 			if (match(entry, data)) {
@@ -2157,7 +2158,7 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
 		goto out_bug;
 
 	for (;;) {
-		int distance = curr->lockdep_depth - depth + 1;
+		u16 distance = curr->lockdep_depth - depth + 1;
 		hlock = curr->held_locks + depth - 1;
 		/*
 		 * Only non-crosslock entries get new dependencies added.