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lockdep: BFS cleanup

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Some cleanups of the lockdep code after the BFS series:

 - Remove the last traces of the generation id
 - Fixup comment style
 - Move the bfs routines into lockdep.c
 - Cleanup the bfs routines

[ tom.leiming@gmail.com: Fix crash ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1246201486-7308-11-git-send-email-tom.leiming@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra
2009-07-16 15:44:29 +02:00
parent 12f3dfd022
commit af01296145
3 changed files with 175 additions and 213 deletions
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97
kernel/lockdep_internals.h
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@ -91,6 +91,8 @@ extern unsigned int nr_process_chains;
extern unsigned int max_lockdep_depth;
extern unsigned int max_recursion_depth;
extern unsigned int max_bfs_queue_depth;
#ifdef CONFIG_PROVE_LOCKING
extern unsigned long lockdep_count_forward_deps(struct lock_class *);
extern unsigned long lockdep_count_backward_deps(struct lock_class *);
@ -136,98 +138,3 @@ extern atomic_t nr_find_usage_backwards_recursions;
# define debug_atomic_dec(ptr) do { } while (0)
# define debug_atomic_read(ptr) 0
#endif
extern unsigned int max_bfs_queue_depth;
extern unsigned long nr_list_entries;
extern struct lock_list list_entries[MAX_LOCKDEP_ENTRIES];
extern unsigned long bfs_accessed[];
/*For good efficiency of modular, we use power of 2*/
#define MAX_CIRCULAR_QUE_SIZE 4096UL
/* The circular_queue and helpers is used to implement the
* breadth-first search(BFS)algorithem, by which we can build
* the shortest path from the next lock to be acquired to the
* previous held lock if there is a circular between them.
* */
struct circular_queue{
unsigned long element[MAX_CIRCULAR_QUE_SIZE];
unsigned int front, rear;
};
static inline void __cq_init(struct circular_queue *cq)
{
cq->front = cq->rear = 0;
bitmap_zero(bfs_accessed, MAX_LOCKDEP_ENTRIES);
}
static inline int __cq_empty(struct circular_queue *cq)
{
return (cq->front == cq->rear);
}
static inline int __cq_full(struct circular_queue *cq)
{
return ((cq->rear + 1)&(MAX_CIRCULAR_QUE_SIZE-1)) == cq->front;
}
static inline int __cq_enqueue(struct circular_queue *cq, unsigned long elem)
{
if (__cq_full(cq))
return -1;
cq->element[cq->rear] = elem;
cq->rear = (cq->rear + 1)&(MAX_CIRCULAR_QUE_SIZE-1);
return 0;
}
static inline int __cq_dequeue(struct circular_queue *cq, unsigned long *elem)
{
if (__cq_empty(cq))
return -1;
*elem = cq->element[cq->front];
cq->front = (cq->front + 1)&(MAX_CIRCULAR_QUE_SIZE-1);
return 0;
}
static inline unsigned int __cq_get_elem_count(struct circular_queue *cq)
{
return (cq->rear - cq->front)&(MAX_CIRCULAR_QUE_SIZE-1);
}
static inline void mark_lock_accessed(struct lock_list *lock,
struct lock_list *parent)
{
unsigned long nr;
nr = lock - list_entries;
WARN_ON(nr >= nr_list_entries);
lock->parent = parent;
set_bit(nr, bfs_accessed);
}
static inline unsigned long lock_accessed(struct lock_list *lock)
{
unsigned long nr;
nr = lock - list_entries;
WARN_ON(nr >= nr_list_entries);
return test_bit(nr, bfs_accessed);
}
static inline struct lock_list *get_lock_parent(struct lock_list *child)
{
return child->parent;
}
static inline int get_lock_depth(struct lock_list *child)
{
int depth = 0;
struct lock_list *parent;
while ((parent = get_lock_parent(child))) {
child = parent;
depth++;
}
return depth;
}