static inline int graph_unlock(void)
{
+ if (debug_locks && !__raw_spin_is_locked(&lockdep_lock))
+ return DEBUG_LOCKS_WARN_ON(1);
+
__raw_spin_unlock(&lockdep_lock);
return 0;
}
trace->entries = stack_trace + nr_stack_trace_entries;
trace->skip = 3;
- trace->all_contexts = 0;
- save_stack_trace(trace, NULL);
+ save_stack_trace(trace);
trace->max_entries = trace->nr_entries;
const char * __get_key_name(struct lockdep_subclass_key *key, char *str)
{
- unsigned long offs, size;
- char *modname;
-
- return kallsyms_lookup((unsigned long)key, &size, &offs, &modname, str);
+ return kallsyms_lookup((unsigned long)key, NULL, NULL, NULL, str);
}
void
* Add a new dependency to the head of the list:
*/
static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
- struct list_head *head, unsigned long ip)
+ struct list_head *head, unsigned long ip, int distance)
{
struct lock_list *entry;
/*
return 0;
entry->class = this;
+ entry->distance = distance;
if (!save_trace(&entry->trace))
return 0;
struct lock_list *entry;
int ret;
+ if (!__raw_spin_is_locked(&lockdep_lock))
+ return DEBUG_LOCKS_WARN_ON(1);
+
if (depth > max_recursion_depth)
max_recursion_depth = depth;
if (depth >= RECURSION_LIMIT)
*/
static int
check_prev_add(struct task_struct *curr, struct held_lock *prev,
- struct held_lock *next)
+ struct held_lock *next, int distance)
{
struct lock_list *entry;
int ret;
* L2 added to its dependency list, due to the first chain.)
*/
list_for_each_entry(entry, &prev->class->locks_after, entry) {
- if (entry->class == next->class)
+ if (entry->class == next->class) {
+ if (distance == 1)
+ entry->distance = 1;
return 2;
+ }
}
/*
* to the previous lock's dependency list:
*/
ret = add_lock_to_list(prev->class, next->class,
- &prev->class->locks_after, next->acquire_ip);
+ &prev->class->locks_after, next->acquire_ip, distance);
+
if (!ret)
return 0;
ret = add_lock_to_list(next->class, prev->class,
- &next->class->locks_before, next->acquire_ip);
+ &next->class->locks_before, next->acquire_ip, distance);
if (!ret)
return 0;
goto out_bug;
for (;;) {
+ int distance = curr->lockdep_depth - depth + 1;
hlock = curr->held_locks + depth-1;
/*
* Only non-recursive-read entries get new dependencies
* added:
*/
if (hlock->read != 2) {
- if (!check_prev_add(curr, hlock, next))
+ if (!check_prev_add(curr, hlock, next, distance))
return 0;
/*
* Stop after the first non-trylock entry,
if (!subclass || force)
lock->class_cache = class;
- DEBUG_LOCKS_WARN_ON(class->subclass != subclass);
+ if (DEBUG_LOCKS_WARN_ON(class->subclass != subclass))
+ return NULL;
return class;
}
/*
* Look up a dependency chain. If the key is not present yet then
- * add it and return 0 - in this case the new dependency chain is
- * validated. If the key is already hashed, return 1.
+ * add it and return 1 - in this case the new dependency chain is
+ * validated. If the key is already hashed, return 0.
+ * (On return with 1 graph_lock is held.)
*/
static inline int lookup_chain_cache(u64 chain_key, struct lock_class *class)
{
struct list_head *hash_head = chainhashentry(chain_key);
struct lock_chain *chain;
- DEBUG_LOCKS_WARN_ON(!irqs_disabled());
+ if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
+ return 0;
/*
* We can walk it lock-free, because entries only get added
* to the hash:
return;
}
id = hlock->class - lock_classes;
- DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS);
+ if (DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS))
+ return;
+
if (prev_hlock && (prev_hlock->irq_context !=
hlock->irq_context))
chain_key = 0;
* Mark a lock with a usage bit, and validate the state transition:
*/
static int mark_lock(struct task_struct *curr, struct held_lock *this,
- enum lock_usage_bit new_bit, unsigned long ip)
+ enum lock_usage_bit new_bit)
{
unsigned int new_mask = 1 << new_bit, ret = 1;
this->class->usage_mask |= new_mask;
-#ifdef CONFIG_TRACE_IRQFLAGS
- if (new_bit == LOCK_ENABLED_HARDIRQS ||
- new_bit == LOCK_ENABLED_HARDIRQS_READ)
- ip = curr->hardirq_enable_ip;
- else if (new_bit == LOCK_ENABLED_SOFTIRQS ||
- new_bit == LOCK_ENABLED_SOFTIRQS_READ)
- ip = curr->softirq_enable_ip;
-#endif
if (!save_trace(this->class->usage_traces + new_bit))
return 0;
* Mark all held locks with a usage bit:
*/
static int
-mark_held_locks(struct task_struct *curr, int hardirq, unsigned long ip)
+mark_held_locks(struct task_struct *curr, int hardirq)
{
enum lock_usage_bit usage_bit;
struct held_lock *hlock;
else
usage_bit = LOCK_ENABLED_SOFTIRQS;
}
- if (!mark_lock(curr, hlock, usage_bit, ip))
+ if (!mark_lock(curr, hlock, usage_bit))
return 0;
}
* We are going to turn hardirqs on, so set the
* usage bit for all held locks:
*/
- if (!mark_held_locks(curr, 1, ip))
+ if (!mark_held_locks(curr, 1))
return;
/*
* If we have softirqs enabled, then set the usage
* this bit from being set before)
*/
if (curr->softirqs_enabled)
- if (!mark_held_locks(curr, 0, ip))
+ if (!mark_held_locks(curr, 0))
return;
curr->hardirq_enable_ip = ip;
* enabled too:
*/
if (curr->hardirqs_enabled)
- mark_held_locks(curr, 0, ip);
+ mark_held_locks(curr, 0);
}
/*
if (read) {
if (curr->hardirq_context)
if (!mark_lock(curr, hlock,
- LOCK_USED_IN_HARDIRQ_READ, ip))
+ LOCK_USED_IN_HARDIRQ_READ))
return 0;
if (curr->softirq_context)
if (!mark_lock(curr, hlock,
- LOCK_USED_IN_SOFTIRQ_READ, ip))
+ LOCK_USED_IN_SOFTIRQ_READ))
return 0;
} else {
if (curr->hardirq_context)
- if (!mark_lock(curr, hlock, LOCK_USED_IN_HARDIRQ, ip))
+ if (!mark_lock(curr, hlock, LOCK_USED_IN_HARDIRQ))
return 0;
if (curr->softirq_context)
- if (!mark_lock(curr, hlock, LOCK_USED_IN_SOFTIRQ, ip))
+ if (!mark_lock(curr, hlock, LOCK_USED_IN_SOFTIRQ))
return 0;
}
}
if (!hardirqs_off) {
if (read) {
if (!mark_lock(curr, hlock,
- LOCK_ENABLED_HARDIRQS_READ, ip))
+ LOCK_ENABLED_HARDIRQS_READ))
return 0;
if (curr->softirqs_enabled)
if (!mark_lock(curr, hlock,
- LOCK_ENABLED_SOFTIRQS_READ, ip))
+ LOCK_ENABLED_SOFTIRQS_READ))
return 0;
} else {
if (!mark_lock(curr, hlock,
- LOCK_ENABLED_HARDIRQS, ip))
+ LOCK_ENABLED_HARDIRQS))
return 0;
if (curr->softirqs_enabled)
if (!mark_lock(curr, hlock,
- LOCK_ENABLED_SOFTIRQS, ip))
+ LOCK_ENABLED_SOFTIRQS))
return 0;
}
}
#endif
/* mark it as used: */
- if (!mark_lock(curr, hlock, LOCK_USED, ip))
+ if (!mark_lock(curr, hlock, LOCK_USED))
return 0;
out_calc_hash:
/*
if (!check_prevs_add(curr, hlock))
return 0;
graph_unlock();
- }
+ } else
+ /* after lookup_chain_cache(): */
+ if (unlikely(!debug_locks))
+ return 0;
+
curr->lockdep_depth++;
check_chain_key(curr);
+#ifdef CONFIG_DEBUG_LOCKDEP
+ if (unlikely(!debug_locks))
+ return 0;
+#endif
if (unlikely(curr->lockdep_depth >= MAX_LOCK_DEPTH)) {
debug_locks_off();
printk("BUG: MAX_LOCK_DEPTH too low!\n");
printk("turning off the locking correctness validator.\n");
return 0;
}
+
if (unlikely(curr->lockdep_depth > max_lockdep_depth))
max_lockdep_depth = curr->lockdep_depth;
raw_local_irq_restore(flags);
}
-void __init lockdep_init(void)
+void lockdep_init(void)
{
int i;
int count = 10;
int unlock = 1;
+ if (unlikely(!debug_locks)) {
+ printk("INFO: lockdep is turned off.\n");
+ return;
+ }
printk("\nShowing all locks held in the system:\n");
/*
void debug_show_held_locks(struct task_struct *task)
{
+ if (unlikely(!debug_locks)) {
+ printk("INFO: lockdep is turned off.\n");
+ return;
+ }
lockdep_print_held_locks(task);
}
EXPORT_SYMBOL_GPL(debug_show_held_locks);
-
git.samba.org / sfrench / cifs-2.6.git / blobdiff