diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/lockdep.c | 23 | ||||
| -rw-r--r-- | kernel/lockdep_internals.h | 35 |
2 files changed, 39 insertions, 19 deletions
diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 93dc70d18cdf..5dcca26a8263 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -42,7 +42,7 @@ #include <linux/hash.h> #include <linux/ftrace.h> #include <linux/stringify.h> - +#include <linux/bitops.h> #include <asm/sections.h> #include "lockdep_internals.h" @@ -118,7 +118,7 @@ static inline int debug_locks_off_graph_unlock(void) static int lockdep_initialized; unsigned long nr_list_entries; -static struct lock_list list_entries[MAX_LOCKDEP_ENTRIES]; +struct lock_list list_entries[MAX_LOCKDEP_ENTRIES]; /* * All data structures here are protected by the global debug_lock. @@ -897,30 +897,38 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this, return 1; } +unsigned long bfs_accessed[BITS_TO_LONGS(MAX_LOCKDEP_ENTRIES)]; static struct circular_queue lock_cq; + static int __search_shortest_path(struct lock_list *source_entry, struct lock_class *target, struct lock_list **target_entry, int forward) { struct lock_list *entry; + struct list_head *head; struct circular_queue *cq = &lock_cq; int ret = 1; - __cq_init(cq); - - mark_lock_accessed(source_entry, NULL); if (source_entry->class == target) { *target_entry = source_entry; ret = 0; goto exit; } + if (forward) + head = &source_entry->class->locks_after; + else + head = &source_entry->class->locks_before; + + if (list_empty(head)) + goto exit; + + __cq_init(cq); __cq_enqueue(cq, (unsigned long)source_entry); while (!__cq_empty(cq)) { struct lock_list *lock; - struct list_head *head; __cq_dequeue(cq, (unsigned long *)&lock); @@ -1040,6 +1048,7 @@ static noinline int print_circular_bug(void) return 0; this.class = hlock_class(check_source); + this.parent = NULL; if (!save_trace(&this.trace)) return 0; @@ -1580,10 +1589,10 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, */ check_source = next; check_target = prev; + if (check_noncircular(hlock_class(next), 0) == 2) return print_circular_bug(); - if (!check_prev_add_irq(curr, prev, next)) return 0; diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h index 6f48d37d5be2..c2f6594966f3 100644 --- a/kernel/lockdep_internals.h +++ b/kernel/lockdep_internals.h @@ -137,23 +137,28 @@ extern atomic_t nr_find_usage_backwards_recursions; # define debug_atomic_read(ptr) 0 #endif + +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. * */ -#define MAX_CIRCULAR_QUE_SIZE 4096UL struct circular_queue{ unsigned long element[MAX_CIRCULAR_QUE_SIZE]; unsigned int front, rear; }; -#define LOCK_ACCESSED 1UL -#define LOCK_ACCESSED_MASK (~LOCK_ACCESSED) - 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) @@ -163,7 +168,7 @@ static inline int __cq_empty(struct circular_queue *cq) static inline int __cq_full(struct circular_queue *cq) { - return ((cq->rear + 1)%MAX_CIRCULAR_QUE_SIZE) == cq->front; + return ((cq->rear + 1)&(MAX_CIRCULAR_QUE_SIZE-1)) == cq->front; } static inline int __cq_enqueue(struct circular_queue *cq, unsigned long elem) @@ -172,7 +177,7 @@ static inline int __cq_enqueue(struct circular_queue *cq, unsigned long elem) return -1; cq->element[cq->rear] = elem; - cq->rear = (cq->rear + 1)%MAX_CIRCULAR_QUE_SIZE; + cq->rear = (cq->rear + 1)&(MAX_CIRCULAR_QUE_SIZE-1); return 0; } @@ -182,30 +187,36 @@ static inline int __cq_dequeue(struct circular_queue *cq, unsigned long *elem) return -1; *elem = cq->element[cq->front]; - cq->front = (cq->front + 1)%MAX_CIRCULAR_QUE_SIZE; + cq->front = (cq->front + 1)&(MAX_CIRCULAR_QUE_SIZE-1); return 0; } static inline int __cq_get_elem_count(struct circular_queue *cq) { - return (cq->rear - cq->front)%MAX_CIRCULAR_QUE_SIZE; + return (cq->rear - cq->front)&(MAX_CIRCULAR_QUE_SIZE-1); } static inline void mark_lock_accessed(struct lock_list *lock, struct lock_list *parent) { - lock->parent = (void *) parent + LOCK_ACCESSED; + 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) { - return (unsigned long)lock->parent & LOCK_ACCESSED; + 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 (struct lock_list *) - ((unsigned long)child->parent & LOCK_ACCESSED_MASK); + return child->parent; } static inline unsigned long get_lock_depth(struct lock_list *child) |