#include <linux/irqflags.h>
#include <linux/utsname.h>
#include <linux/hash.h>
+#include <linux/ftrace.h>
#include <asm/sections.h>
__raw_spin_unlock(&lockdep_lock);
return 0;
}
+ /* prevent any recursions within lockdep from causing deadlocks */
+ current->lockdep_recursion++;
return 1;
}
if (debug_locks && !__raw_spin_is_locked(&lockdep_lock))
return DEBUG_LOCKS_WARN_ON(1);
+ current->lockdep_recursion--;
__raw_spin_unlock(&lockdep_lock);
return 0;
}
* parallel walking of the hash-list safe:
*/
list_add_tail_rcu(&class->hash_entry, hash_head);
+ /*
+ * Add it to the global list of classes:
+ */
+ list_add_tail_rcu(&class->lock_entry, &all_lock_classes);
if (verbose(class)) {
graph_unlock();
return 1;
}
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
/*
* Forwards and backwards subgraph searching, for the purposes of
* proving that two subgraphs can be connected by a new dependency
}
unsigned long nr_lock_chains;
-static struct lock_chain lock_chains[MAX_LOCKDEP_CHAINS];
+struct lock_chain lock_chains[MAX_LOCKDEP_CHAINS];
+int nr_chain_hlocks;
+static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS];
+
+struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i)
+{
+ return lock_classes + chain_hlocks[chain->base + i];
+}
/*
* Look up a dependency chain. If the key is not present yet then
* 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)
+static inline int lookup_chain_cache(struct task_struct *curr,
+ struct held_lock *hlock,
+ u64 chain_key)
{
+ struct lock_class *class = hlock->class;
struct list_head *hash_head = chainhashentry(chain_key);
struct lock_chain *chain;
+ struct held_lock *hlock_curr, *hlock_next;
+ int i, j, n, cn;
if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
return 0;
}
chain = lock_chains + nr_lock_chains++;
chain->chain_key = chain_key;
+ chain->irq_context = hlock->irq_context;
+ /* Find the first held_lock of current chain */
+ hlock_next = hlock;
+ for (i = curr->lockdep_depth - 1; i >= 0; i--) {
+ hlock_curr = curr->held_locks + i;
+ if (hlock_curr->irq_context != hlock_next->irq_context)
+ break;
+ hlock_next = hlock;
+ }
+ i++;
+ chain->depth = curr->lockdep_depth + 1 - i;
+ cn = nr_chain_hlocks;
+ while (cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS) {
+ n = cmpxchg(&nr_chain_hlocks, cn, cn + chain->depth);
+ if (n == cn)
+ break;
+ cn = n;
+ }
+ if (likely(cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) {
+ chain->base = cn;
+ for (j = 0; j < chain->depth - 1; j++, i++) {
+ int lock_id = curr->held_locks[i].class - lock_classes;
+ chain_hlocks[chain->base + j] = lock_id;
+ }
+ chain_hlocks[chain->base + j] = class - lock_classes;
+ }
list_add_tail_rcu(&chain->entry, hash_head);
debug_atomic_inc(&chain_lookup_misses);
inc_chains();
* graph_lock for us)
*/
if (!hlock->trylock && (hlock->check == 2) &&
- lookup_chain_cache(chain_key, hlock->class)) {
+ lookup_chain_cache(curr, hlock, chain_key)) {
/*
* Check whether last held lock:
*
static int mark_lock(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit new_bit);
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
/*
* print irq inversion bug:
/*
* Hardirqs will be enabled:
*/
-void trace_hardirqs_on(void)
+void trace_hardirqs_on_caller(unsigned long a0)
{
struct task_struct *curr = current;
unsigned long ip;
+ time_hardirqs_on(CALLER_ADDR0, a0);
+
if (unlikely(!debug_locks || current->lockdep_recursion))
return;
curr->hardirq_enable_event = ++curr->irq_events;
debug_atomic_inc(&hardirqs_on_events);
}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+void trace_hardirqs_on(void)
+{
+ trace_hardirqs_on_caller(CALLER_ADDR0);
+}
EXPORT_SYMBOL(trace_hardirqs_on);
/*
* Hardirqs were disabled:
*/
-void trace_hardirqs_off(void)
+void trace_hardirqs_off_caller(unsigned long a0)
{
struct task_struct *curr = current;
+ time_hardirqs_off(CALLER_ADDR0, a0);
+
if (unlikely(!debug_locks || current->lockdep_recursion))
return;
} else
debug_atomic_inc(&redundant_hardirqs_off);
}
+EXPORT_SYMBOL(trace_hardirqs_off_caller);
+void trace_hardirqs_off(void)
+{
+ trace_hardirqs_off_caller(CALLER_ADDR0);
+}
EXPORT_SYMBOL(trace_hardirqs_off);
/*
* 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)
+ enum lock_usage_bit new_bit)
{
unsigned int new_mask = 1 << new_bit, ret = 1;
return 0;
break;
case LOCK_USED:
- /*
- * Add it to the global list of classes:
- */
- list_add_tail_rcu(&this->class->lock_entry, &all_lock_classes);
debug_atomic_dec(&nr_unused_locks);
break;
default:
return 0;
/*
- * Calculate the chain hash: it's the combined has of all the
+ * Calculate the chain hash: it's the combined hash of all the
* lock keys along the dependency chain. We save the hash value
* at every step so that we can get the current hash easily
* after unlock. The chain hash is then used to cache dependency
*/
static void check_flags(unsigned long flags)
{
-#if defined(CONFIG_DEBUG_LOCKDEP) && defined(CONFIG_TRACE_IRQFLAGS)
+#if defined(CONFIG_PROVE_LOCKING) && defined(CONFIG_DEBUG_LOCKDEP) && \
+ defined(CONFIG_TRACE_IRQFLAGS)
if (!debug_locks)
return;
- if (irqs_disabled_flags(flags))
- DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled);
- else
- DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled);
+ if (irqs_disabled_flags(flags)) {
+ if (DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)) {
+ printk("possible reason: unannotated irqs-off.\n");
+ }
+ } else {
+ if (DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled)) {
+ printk("possible reason: unannotated irqs-on.\n");
+ }
+ }
/*
* We dont accurately track softirq state in e.g.
* and also avoid lockdep recursion:
*/
void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
- int trylock, int read, int check, unsigned long ip)
+ int trylock, int read, int check, unsigned long ip)
{
unsigned long flags;
EXPORT_SYMBOL_GPL(lock_acquire);
-void lock_release(struct lockdep_map *lock, int nested, unsigned long ip)
+void lock_release(struct lockdep_map *lock, int nested,
+ unsigned long ip)
{
unsigned long flags;
}
-static inline int within(void *addr, void *start, unsigned long size)
+static inline int within(const void *addr, void *start, unsigned long size)
{
return addr >= start && addr < start + size;
}
struct list_head *head;
unsigned long flags;
int i;
+ int locked;
raw_local_irq_save(flags);
- graph_lock();
+ locked = graph_lock();
/*
* Unhash all classes that were created by this module:
head = classhash_table + i;
if (list_empty(head))
continue;
- list_for_each_entry_safe(class, next, head, hash_entry)
+ list_for_each_entry_safe(class, next, head, hash_entry) {
if (within(class->key, start, size))
zap_class(class);
+ else if (within(class->name, start, size))
+ zap_class(class);
+ }
}
- graph_unlock();
+ if (locked)
+ graph_unlock();
raw_local_irq_restore(flags);
}
struct list_head *head;
unsigned long flags;
int i, j;
+ int locked;
raw_local_irq_save(flags);
* Debug check: in the end all mapped classes should
* be gone.
*/
- graph_lock();
+ locked = graph_lock();
for (i = 0; i < CLASSHASH_SIZE; i++) {
head = classhash_table + i;
if (list_empty(head))
}
}
}
- graph_unlock();
+ if (locked)
+ graph_unlock();
out_restore:
raw_local_irq_restore(flags);
#endif
}
-static inline int in_range(const void *start, const void *addr, const void *end)
-{
- return addr >= start && addr <= end;
-}
-
static void
print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
const void *mem_to, struct held_lock *hlock)
dump_stack();
}
+static inline int not_in_range(const void* mem_from, unsigned long mem_len,
+ const void* lock_from, unsigned long lock_len)
+{
+ return lock_from + lock_len <= mem_from ||
+ mem_from + mem_len <= lock_from;
+}
+
/*
* Called when kernel memory is freed (or unmapped), or if a lock
* is destroyed or reinitialized - this code checks whether there is
*/
void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
{
- const void *mem_to = mem_from + mem_len, *lock_from, *lock_to;
struct task_struct *curr = current;
struct held_lock *hlock;
unsigned long flags;
for (i = 0; i < curr->lockdep_depth; i++) {
hlock = curr->held_locks + i;
- lock_from = (void *)hlock->instance;
- lock_to = (void *)(hlock->instance + 1);
-
- if (!in_range(mem_from, lock_from, mem_to) &&
- !in_range(mem_from, lock_to, mem_to))
+ if (not_in_range(mem_from, mem_len, hlock->instance,
+ sizeof(*hlock->instance)))
continue;
- print_freed_lock_bug(curr, mem_from, mem_to, hlock);
+ print_freed_lock_bug(curr, mem_from, mem_from + mem_len, hlock);
break;
}
local_irq_restore(flags);
printk(" locked it.\n");
do_each_thread(g, p) {
+ /*
+ * It's not reliable to print a task's held locks
+ * if it's not sleeping (or if it's not the current
+ * task):
+ */
+ if (p->state == TASK_RUNNING && p != current)
+ continue;
if (p->lockdep_depth)
lockdep_print_held_locks(p);
if (!unlock)
EXPORT_SYMBOL_GPL(debug_show_all_locks);
-void debug_show_held_locks(struct task_struct *task)
+/*
+ * Careful: only use this function if you are sure that
+ * the task cannot run in parallel!
+ */
+void __debug_show_held_locks(struct task_struct *task)
{
if (unlikely(!debug_locks)) {
printk("INFO: lockdep is turned off.\n");
}
lockdep_print_held_locks(task);
}
+EXPORT_SYMBOL_GPL(__debug_show_held_locks);
+
+void debug_show_held_locks(struct task_struct *task)
+{
+ __debug_show_held_locks(task);
+}
EXPORT_SYMBOL_GPL(debug_show_held_locks);