lockdep: Add statistics info for max bfs queue depth

Add BFS statistics to the existing lockdep stats.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1246201486-7308-10-git-send-email-tom.leiming@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ming Lei 2009-07-16 15:44:29 +02:00 committed by Peter Zijlstra
parent 4dd861d646
commit 12f3dfd022
3 changed files with 9 additions and 2 deletions

View file

@ -929,7 +929,7 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
unsigned long bfs_accessed[BITS_TO_LONGS(MAX_LOCKDEP_ENTRIES)]; unsigned long bfs_accessed[BITS_TO_LONGS(MAX_LOCKDEP_ENTRIES)];
static struct circular_queue lock_cq; static struct circular_queue lock_cq;
unsigned int max_bfs_queue_depth;
static int __bfs(struct lock_list *source_entry, static int __bfs(struct lock_list *source_entry,
void *data, void *data,
int (*match)(struct lock_list *entry, void *data), int (*match)(struct lock_list *entry, void *data),
@ -975,6 +975,7 @@ static int __bfs(struct lock_list *source_entry,
list_for_each_entry(entry, head, entry) { list_for_each_entry(entry, head, entry) {
if (!lock_accessed(entry)) { if (!lock_accessed(entry)) {
unsigned int cq_depth;
mark_lock_accessed(entry, lock); mark_lock_accessed(entry, lock);
if (match(entry, data)) { if (match(entry, data)) {
*target_entry = entry; *target_entry = entry;
@ -986,6 +987,9 @@ static int __bfs(struct lock_list *source_entry,
ret = -1; ret = -1;
goto exit; goto exit;
} }
cq_depth = __cq_get_elem_count(cq);
if (max_bfs_queue_depth < cq_depth)
max_bfs_queue_depth = cq_depth;
} }
} }
} }

View file

@ -138,6 +138,7 @@ extern atomic_t nr_find_usage_backwards_recursions;
#endif #endif
extern unsigned int max_bfs_queue_depth;
extern unsigned long nr_list_entries; extern unsigned long nr_list_entries;
extern struct lock_list list_entries[MAX_LOCKDEP_ENTRIES]; extern struct lock_list list_entries[MAX_LOCKDEP_ENTRIES];
extern unsigned long bfs_accessed[]; extern unsigned long bfs_accessed[];
@ -191,7 +192,7 @@ static inline int __cq_dequeue(struct circular_queue *cq, unsigned long *elem)
return 0; return 0;
} }
static inline int __cq_get_elem_count(struct circular_queue *cq) static inline unsigned int __cq_get_elem_count(struct circular_queue *cq)
{ {
return (cq->rear - cq->front)&(MAX_CIRCULAR_QUE_SIZE-1); return (cq->rear - cq->front)&(MAX_CIRCULAR_QUE_SIZE-1);
} }

View file

@ -411,6 +411,8 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
max_lockdep_depth); max_lockdep_depth);
seq_printf(m, " max recursion depth: %11u\n", seq_printf(m, " max recursion depth: %11u\n",
max_recursion_depth); max_recursion_depth);
seq_printf(m, " max bfs queue depth: %11u\n",
max_bfs_queue_depth);
lockdep_stats_debug_show(m); lockdep_stats_debug_show(m);
seq_printf(m, " debug_locks: %11u\n", seq_printf(m, " debug_locks: %11u\n",
debug_locks); debug_locks);