#include <linux/ftrace.h>
#include <linux/stringify.h>
#include <linux/bitops.h>
+#include <linux/gfp.h>
#include <asm/sections.h>
#include "lockdep_internals.h"
#define CREATE_TRACE_POINTS
-#include <trace/events/lockdep.h>
+#include <trace/events/lock.h>
#ifdef CONFIG_PROVE_LOCKING
int prove_locking = 1;
* to use a raw spinlock - we really dont want the spinlock
* code to recurse back into the lockdep code...
*/
-static raw_spinlock_t lockdep_lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+static arch_spinlock_t lockdep_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
static int graph_lock(void)
{
- __raw_spin_lock(&lockdep_lock);
+ arch_spin_lock(&lockdep_lock);
/*
* Make sure that if another CPU detected a bug while
* walking the graph we dont change it (while the other
* dropped already)
*/
if (!debug_locks) {
- __raw_spin_unlock(&lockdep_lock);
+ arch_spin_unlock(&lockdep_lock);
return 0;
}
/* prevent any recursions within lockdep from causing deadlocks */
static inline int graph_unlock(void)
{
- if (debug_locks && !__raw_spin_is_locked(&lockdep_lock))
+ if (debug_locks && !arch_spin_is_locked(&lockdep_lock))
return DEBUG_LOCKS_WARN_ON(1);
current->lockdep_recursion--;
- __raw_spin_unlock(&lockdep_lock);
+ arch_spin_unlock(&lockdep_lock);
return 0;
}
{
int ret = debug_locks_off();
- __raw_spin_unlock(&lockdep_lock);
+ arch_spin_unlock(&lockdep_lock);
return ret;
}
}
#ifdef CONFIG_LOCK_STAT
-static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats);
+static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS],
+ cpu_lock_stats);
+
+static inline u64 lockstat_clock(void)
+{
+ return cpu_clock(smp_processor_id());
+}
static int lock_point(unsigned long points[], unsigned long ip)
{
return i;
}
-static void lock_time_inc(struct lock_time *lt, s64 time)
+static void lock_time_inc(struct lock_time *lt, u64 time)
{
if (time > lt->max)
lt->max = time;
- if (time < lt->min || !lt->min)
+ if (time < lt->min || !lt->nr)
lt->min = time;
lt->total += time;
static inline void lock_time_add(struct lock_time *src, struct lock_time *dst)
{
- dst->min += src->min;
- dst->max += src->max;
+ if (!src->nr)
+ return;
+
+ if (src->max > dst->max)
+ dst->max = src->max;
+
+ if (src->min < dst->min || !dst->nr)
+ dst->min = src->min;
+
dst->total += src->total;
dst->nr += src->nr;
}
memset(&stats, 0, sizeof(struct lock_class_stats));
for_each_possible_cpu(cpu) {
struct lock_class_stats *pcs =
- &per_cpu(lock_stats, cpu)[class - lock_classes];
+ &per_cpu(cpu_lock_stats, cpu)[class - lock_classes];
for (i = 0; i < ARRAY_SIZE(stats.contention_point); i++)
stats.contention_point[i] += pcs->contention_point[i];
for_each_possible_cpu(cpu) {
struct lock_class_stats *cpu_stats =
- &per_cpu(lock_stats, cpu)[class - lock_classes];
+ &per_cpu(cpu_lock_stats, cpu)[class - lock_classes];
memset(cpu_stats, 0, sizeof(struct lock_class_stats));
}
static struct lock_class_stats *get_lock_stats(struct lock_class *class)
{
- return &get_cpu_var(lock_stats)[class - lock_classes];
+ return &get_cpu_var(cpu_lock_stats)[class - lock_classes];
}
static void put_lock_stats(struct lock_class_stats *stats)
{
- put_cpu_var(lock_stats);
+ put_cpu_var(cpu_lock_stats);
}
static void lock_release_holdtime(struct held_lock *hlock)
{
struct lock_class_stats *stats;
- s64 holdtime;
+ u64 holdtime;
if (!lock_stat)
return;
- holdtime = sched_clock() - hlock->holdtime_stamp;
+ holdtime = lockstat_clock() - hlock->holdtime_stamp;
stats = get_lock_stats(hlock_class(hlock));
if (hlock->read)
* complete trace that maxes out the entries provided will be reported
* as incomplete, friggin useless </rant>
*/
- if (trace->entries[trace->nr_entries-1] == ULONG_MAX)
+ if (trace->nr_entries != 0 &&
+ trace->entries[trace->nr_entries-1] == ULONG_MAX)
trace->nr_entries--;
trace->max_entries = trace->nr_entries;
unsigned int nr_softirq_chains;
unsigned int nr_process_chains;
unsigned int max_lockdep_depth;
-unsigned int max_recursion_depth;
#ifdef CONFIG_DEBUG_LOCKDEP
/*
/*
* Various lockdep statistics:
*/
-atomic_t chain_lookup_hits;
-atomic_t chain_lookup_misses;
-atomic_t hardirqs_on_events;
-atomic_t hardirqs_off_events;
-atomic_t redundant_hardirqs_on;
-atomic_t redundant_hardirqs_off;
-atomic_t softirqs_on_events;
-atomic_t softirqs_off_events;
-atomic_t redundant_softirqs_on;
-atomic_t redundant_softirqs_off;
-atomic_t nr_unused_locks;
-atomic_t nr_cyclic_checks;
-atomic_t nr_cyclic_check_recursions;
-atomic_t nr_find_usage_forwards_checks;
-atomic_t nr_find_usage_forwards_recursions;
-atomic_t nr_find_usage_backwards_checks;
-atomic_t nr_find_usage_backwards_recursions;
+DEFINE_PER_CPU(struct lockdep_stats, lockdep_stats);
#endif
/*
unsigned long start = (unsigned long) &_stext,
end = (unsigned long) &_end,
addr = (unsigned long) obj;
-#ifdef CONFIG_SMP
- int i;
-#endif
/*
* static variable?
if ((addr >= start) && (addr < end))
return 1;
-#ifdef CONFIG_SMP
+ if (arch_is_kernel_data(addr))
+ return 1;
+
/*
- * percpu var?
+ * in-kernel percpu var?
*/
- for_each_possible_cpu(i) {
- start = (unsigned long) &__per_cpu_start + per_cpu_offset(i);
- end = (unsigned long) &__per_cpu_start + PERCPU_ENOUGH_ROOM
- + per_cpu_offset(i);
-
- if ((addr >= start) && (addr < end))
- return 1;
- }
-#endif
+ if (is_kernel_percpu_address(addr))
+ return 1;
/*
- * module var?
+ * module static or percpu var?
*/
- return is_module_address(addr);
+ return is_module_address(addr) || is_module_percpu_address(addr);
}
/*
return NULL;
}
class = lock_classes + nr_lock_classes++;
- debug_atomic_inc(&nr_unused_locks);
+ debug_atomic_inc(nr_unused_locks);
class->key = key;
class->name = lock->name;
class->subclass = subclass;
* 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, int distance)
+ struct list_head *head, unsigned long ip,
+ int distance, struct stack_trace *trace)
{
struct lock_list *entry;
/*
if (!entry)
return 0;
- if (!save_trace(&entry->trace))
- return 0;
-
entry->class = this;
entry->distance = distance;
+ entry->trace = *trace;
/*
* Since we never remove from the dependency list, the list can
* be walked lockless by other CPUs, it's only allocation
return 1;
}
-/*For good efficiency of modular, we use power of 2*/
+/*
+ * For good efficiency of modular, we use power of 2
+ */
#define MAX_CIRCULAR_QUEUE_SIZE 4096UL
#define CQ_MASK (MAX_CIRCULAR_QUEUE_SIZE-1)
-/* The circular_queue and helpers is used to implement the
+/*
+ * 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_QUEUE_SIZE];
unsigned int front, rear;
};
static struct circular_queue lock_cq;
-static unsigned long bfs_accessed[BITS_TO_LONGS(MAX_LOCKDEP_ENTRIES)];
unsigned int max_bfs_queue_depth;
+static unsigned int lockdep_dependency_gen_id;
+
static inline void __cq_init(struct circular_queue *cq)
{
cq->front = cq->rear = 0;
- bitmap_zero(bfs_accessed, MAX_LOCKDEP_ENTRIES);
+ lockdep_dependency_gen_id++;
}
static inline int __cq_empty(struct circular_queue *cq)
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);
+ lock->class->dep_gen_id = lockdep_dependency_gen_id;
}
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);
+ return lock->class->dep_gen_id == lockdep_dependency_gen_id;
}
static inline struct lock_list *get_lock_parent(struct lock_list *child)
this.class = class;
local_irq_save(flags);
- __raw_spin_lock(&lockdep_lock);
+ arch_spin_lock(&lockdep_lock);
ret = __lockdep_count_forward_deps(&this);
- __raw_spin_unlock(&lockdep_lock);
+ arch_spin_unlock(&lockdep_lock);
local_irq_restore(flags);
return ret;
this.class = class;
local_irq_save(flags);
- __raw_spin_lock(&lockdep_lock);
+ arch_spin_lock(&lockdep_lock);
ret = __lockdep_count_backward_deps(&this);
- __raw_spin_unlock(&lockdep_lock);
+ arch_spin_unlock(&lockdep_lock);
local_irq_restore(flags);
return ret;
{
int result;
- debug_atomic_inc(&nr_cyclic_checks);
+ debug_atomic_inc(nr_cyclic_checks);
result = __bfs_forwards(root, target, class_equal, target_entry);
{
int result;
- debug_atomic_inc(&nr_find_usage_forwards_checks);
+ debug_atomic_inc(nr_find_usage_forwards_checks);
result = __bfs_forwards(root, (void *)bit, usage_match, target_entry);
{
int result;
- debug_atomic_inc(&nr_find_usage_backwards_checks);
+ debug_atomic_inc(nr_find_usage_backwards_checks);
result = __bfs_backwards(root, (void *)bit, usage_match, target_entry);
*/
static int
check_prev_add(struct task_struct *curr, struct held_lock *prev,
- struct held_lock *next, int distance)
+ struct held_lock *next, int distance, int trylock_loop)
{
struct lock_list *entry;
int ret;
struct lock_list this;
struct lock_list *uninitialized_var(target_entry);
+ /*
+ * Static variable, serialized by the graph_lock().
+ *
+ * We use this static variable to save the stack trace in case
+ * we call into this function multiple times due to encountering
+ * trylocks in the held lock stack.
+ */
+ static struct stack_trace trace;
/*
* Prove that the new <prev> -> <next> dependency would not
}
}
+ if (!trylock_loop && !save_trace(&trace))
+ return 0;
+
/*
* Ok, all validations passed, add the new lock
* to the previous lock's dependency list:
*/
ret = add_lock_to_list(hlock_class(prev), hlock_class(next),
&hlock_class(prev)->locks_after,
- next->acquire_ip, distance);
+ next->acquire_ip, distance, &trace);
if (!ret)
return 0;
ret = add_lock_to_list(hlock_class(next), hlock_class(prev),
&hlock_class(next)->locks_before,
- next->acquire_ip, distance);
+ next->acquire_ip, distance, &trace);
if (!ret)
return 0;
check_prevs_add(struct task_struct *curr, struct held_lock *next)
{
int depth = curr->lockdep_depth;
+ int trylock_loop = 0;
struct held_lock *hlock;
/*
* added:
*/
if (hlock->read != 2) {
- if (!check_prev_add(curr, hlock, next, distance))
+ if (!check_prev_add(curr, hlock, next,
+ distance, trylock_loop))
return 0;
/*
* Stop after the first non-trylock entry,
if (curr->held_locks[depth].irq_context !=
curr->held_locks[depth-1].irq_context)
break;
+ trylock_loop = 1;
}
return 1;
out_bug:
list_for_each_entry(chain, hash_head, entry) {
if (chain->chain_key == chain_key) {
cache_hit:
- debug_atomic_inc(&chain_lookup_hits);
+ debug_atomic_inc(chain_lookup_hits);
if (very_verbose(class))
printk("\nhash chain already cached, key: "
"%016Lx tail class: [%p] %s\n",
chain_hlocks[chain->base + j] = class - lock_classes;
}
list_add_tail_rcu(&chain->entry, hash_head);
- debug_atomic_inc(&chain_lookup_misses);
+ debug_atomic_inc(chain_lookup_misses);
inc_chains();
return 1;
return ret;
return print_irq_inversion_bug(curr, &root, target_entry,
- this, 1, irqclass);
+ this, 0, irqclass);
}
void print_irqtrace_events(struct task_struct *curr)
return;
if (unlikely(curr->hardirqs_enabled)) {
- debug_atomic_inc(&redundant_hardirqs_on);
+ /*
+ * Neither irq nor preemption are disabled here
+ * so this is racy by nature but loosing one hit
+ * in a stat is not a big deal.
+ */
+ __debug_atomic_inc(redundant_hardirqs_on);
return;
}
/* we'll do an OFF -> ON transition: */
curr->hardirq_enable_ip = ip;
curr->hardirq_enable_event = ++curr->irq_events;
- debug_atomic_inc(&hardirqs_on_events);
+ debug_atomic_inc(hardirqs_on_events);
}
EXPORT_SYMBOL(trace_hardirqs_on_caller);
curr->hardirqs_enabled = 0;
curr->hardirq_disable_ip = ip;
curr->hardirq_disable_event = ++curr->irq_events;
- debug_atomic_inc(&hardirqs_off_events);
+ debug_atomic_inc(hardirqs_off_events);
} else
- debug_atomic_inc(&redundant_hardirqs_off);
+ debug_atomic_inc(redundant_hardirqs_off);
}
EXPORT_SYMBOL(trace_hardirqs_off_caller);
return;
if (curr->softirqs_enabled) {
- debug_atomic_inc(&redundant_softirqs_on);
+ debug_atomic_inc(redundant_softirqs_on);
return;
}
curr->softirqs_enabled = 1;
curr->softirq_enable_ip = ip;
curr->softirq_enable_event = ++curr->irq_events;
- debug_atomic_inc(&softirqs_on_events);
+ debug_atomic_inc(softirqs_on_events);
/*
* We are going to turn softirqs on, so set the
* usage bit for all held locks, if hardirqs are
curr->softirqs_enabled = 0;
curr->softirq_disable_ip = ip;
curr->softirq_disable_event = ++curr->irq_events;
- debug_atomic_inc(&softirqs_off_events);
+ debug_atomic_inc(softirqs_off_events);
DEBUG_LOCKS_WARN_ON(!softirq_count());
} else
- debug_atomic_inc(&redundant_softirqs_off);
+ debug_atomic_inc(redundant_softirqs_off);
}
static void __lockdep_trace_alloc(gfp_t gfp_mask, unsigned long flags)
return 0;
break;
case LOCK_USED:
- debug_atomic_dec(&nr_unused_locks);
+ debug_atomic_dec(nr_unused_locks);
break;
default:
if (!debug_locks_off_graph_unlock())
*/
static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
int trylock, int read, int check, int hardirqs_off,
- struct lockdep_map *nest_lock, unsigned long ip)
+ struct lockdep_map *nest_lock, unsigned long ip,
+ int references)
{
struct task_struct *curr = current;
struct lock_class *class = NULL;
struct held_lock *hlock;
unsigned int depth, id;
int chain_head = 0;
+ int class_idx;
u64 chain_key;
if (!prove_locking)
if (!class)
return 0;
}
- debug_atomic_inc((atomic_t *)&class->ops);
+ atomic_inc((atomic_t *)&class->ops);
if (very_verbose(class)) {
printk("\nacquire class [%p] %s", class->key, class->name);
if (class->name_version > 1)
if (DEBUG_LOCKS_WARN_ON(depth >= MAX_LOCK_DEPTH))
return 0;
+ class_idx = class - lock_classes + 1;
+
+ if (depth) {
+ hlock = curr->held_locks + depth - 1;
+ if (hlock->class_idx == class_idx && nest_lock) {
+ if (hlock->references)
+ hlock->references++;
+ else
+ hlock->references = 2;
+
+ return 1;
+ }
+ }
+
hlock = curr->held_locks + depth;
if (DEBUG_LOCKS_WARN_ON(!class))
return 0;
- hlock->class_idx = class - lock_classes + 1;
+ hlock->class_idx = class_idx;
hlock->acquire_ip = ip;
hlock->instance = lock;
hlock->nest_lock = nest_lock;
hlock->read = read;
hlock->check = check;
hlock->hardirqs_off = !!hardirqs_off;
+ hlock->references = references;
#ifdef CONFIG_LOCK_STAT
hlock->waittime_stamp = 0;
- hlock->holdtime_stamp = sched_clock();
+ hlock->holdtime_stamp = lockstat_clock();
#endif
if (check == 2 && !mark_irqflags(curr, hlock))
return 1;
}
+static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock)
+{
+ if (hlock->instance == lock)
+ return 1;
+
+ if (hlock->references) {
+ struct lock_class *class = lock->class_cache;
+
+ if (!class)
+ class = look_up_lock_class(lock, 0);
+
+ if (DEBUG_LOCKS_WARN_ON(!class))
+ return 0;
+
+ if (DEBUG_LOCKS_WARN_ON(!hlock->nest_lock))
+ return 0;
+
+ if (hlock->class_idx == class - lock_classes + 1)
+ return 1;
+ }
+
+ return 0;
+}
+
static int
__lock_set_class(struct lockdep_map *lock, const char *name,
struct lock_class_key *key, unsigned int subclass,
*/
if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
break;
- if (hlock->instance == lock)
+ if (match_held_lock(hlock, lock))
goto found_it;
prev_hlock = hlock;
}
if (!__lock_acquire(hlock->instance,
hlock_class(hlock)->subclass, hlock->trylock,
hlock->read, hlock->check, hlock->hardirqs_off,
- hlock->nest_lock, hlock->acquire_ip))
+ hlock->nest_lock, hlock->acquire_ip,
+ hlock->references))
return 0;
}
*/
if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
break;
- if (hlock->instance == lock)
+ if (match_held_lock(hlock, lock))
goto found_it;
prev_hlock = hlock;
}
return print_unlock_inbalance_bug(curr, lock, ip);
found_it:
- lock_release_holdtime(hlock);
+ if (hlock->instance == lock)
+ lock_release_holdtime(hlock);
+
+ if (hlock->references) {
+ hlock->references--;
+ if (hlock->references) {
+ /*
+ * We had, and after removing one, still have
+ * references, the current lock stack is still
+ * valid. We're done!
+ */
+ return 1;
+ }
+ }
/*
* We have the right lock to unlock, 'hlock' points to it.
* Now we remove it from the stack, and add back the other
* entries (if any), recalculating the hash along the way:
*/
+
curr->lockdep_depth = i;
curr->curr_chain_key = hlock->prev_chain_key;
if (!__lock_acquire(hlock->instance,
hlock_class(hlock)->subclass, hlock->trylock,
hlock->read, hlock->check, hlock->hardirqs_off,
- hlock->nest_lock, hlock->acquire_ip))
+ hlock->nest_lock, hlock->acquire_ip,
+ hlock->references))
return 0;
}
/*
* Is the unlock non-nested:
*/
- if (hlock->instance != lock)
+ if (hlock->instance != lock || hlock->references)
return lock_release_non_nested(curr, lock, ip);
curr->lockdep_depth--;
check_chain_key(curr);
}
+static int __lock_is_held(struct lockdep_map *lock)
+{
+ struct task_struct *curr = current;
+ int i;
+
+ for (i = 0; i < curr->lockdep_depth; i++) {
+ struct held_lock *hlock = curr->held_locks + i;
+
+ if (match_held_lock(hlock, lock))
+ return 1;
+ }
+
+ return 0;
+}
+
/*
* Check whether we follow the irq-flags state precisely:
*/
{
unsigned long flags;
- trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip);
-
if (unlikely(current->lockdep_recursion))
return;
check_flags(flags);
current->lockdep_recursion = 1;
+ trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip);
__lock_acquire(lock, subclass, trylock, read, check,
- irqs_disabled_flags(flags), nest_lock, ip);
+ irqs_disabled_flags(flags), nest_lock, ip, 0);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
{
unsigned long flags;
- trace_lock_release(lock, nested, ip);
-
if (unlikely(current->lockdep_recursion))
return;
raw_local_irq_save(flags);
check_flags(flags);
current->lockdep_recursion = 1;
+ trace_lock_release(lock, ip);
__lock_release(lock, nested, ip);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(lock_release);
+int lock_is_held(struct lockdep_map *lock)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ if (unlikely(current->lockdep_recursion))
+ return ret;
+
+ raw_local_irq_save(flags);
+ check_flags(flags);
+
+ current->lockdep_recursion = 1;
+ ret = __lock_is_held(lock);
+ current->lockdep_recursion = 0;
+ raw_local_irq_restore(flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(lock_is_held);
+
void lockdep_set_current_reclaim_state(gfp_t gfp_mask)
{
current->lockdep_reclaim_gfp = gfp_mask;
*/
if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
break;
- if (hlock->instance == lock)
+ if (match_held_lock(hlock, lock))
goto found_it;
prev_hlock = hlock;
}
return;
found_it:
- hlock->waittime_stamp = sched_clock();
+ if (hlock->instance != lock)
+ return;
+
+ hlock->waittime_stamp = lockstat_clock();
contention_point = lock_point(hlock_class(hlock)->contention_point, ip);
contending_point = lock_point(hlock_class(hlock)->contending_point,
struct held_lock *hlock, *prev_hlock;
struct lock_class_stats *stats;
unsigned int depth;
- u64 now;
- s64 waittime = 0;
+ u64 now, waittime = 0;
int i, cpu;
depth = curr->lockdep_depth;
*/
if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
break;
- if (hlock->instance == lock)
+ if (match_held_lock(hlock, lock))
goto found_it;
prev_hlock = hlock;
}
return;
found_it:
+ if (hlock->instance != lock)
+ return;
+
cpu = smp_processor_id();
if (hlock->waittime_stamp) {
- now = sched_clock();
+ now = lockstat_clock();
waittime = now - hlock->waittime_stamp;
hlock->holdtime_stamp = now;
}
- trace_lock_acquired(lock, ip, waittime);
+ trace_lock_acquired(lock, ip);
stats = get_lock_stats(hlock_class(hlock));
if (waittime) {
{
unsigned long flags;
- trace_lock_contended(lock, ip);
-
if (unlikely(!lock_stat))
return;
raw_local_irq_save(flags);
check_flags(flags);
current->lockdep_recursion = 1;
+ trace_lock_contended(lock, ip);
__lock_contended(lock, ip);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
sizeof(struct list_head) * CLASSHASH_SIZE +
sizeof(struct lock_list) * MAX_LOCKDEP_ENTRIES +
sizeof(struct lock_chain) * MAX_LOCKDEP_CHAINS +
- sizeof(struct list_head) * CHAINHASH_SIZE) / 1024
+ sizeof(struct list_head) * CHAINHASH_SIZE
#ifdef CONFIG_PROVE_LOCKING
- + sizeof(struct circular_queue) + sizeof(bfs_accessed)
+ + sizeof(struct circular_queue)
#endif
+ ) / 1024
);
printk(" per task-struct memory footprint: %lu bytes\n",
lockdep_print_held_locks(curr);
}
}
+
+void lockdep_rcu_dereference(const char *file, const int line)
+{
+ struct task_struct *curr = current;
+
+#ifndef CONFIG_PROVE_RCU_REPEATEDLY
+ if (!debug_locks_off())
+ return;
+#endif /* #ifdef CONFIG_PROVE_RCU_REPEATEDLY */
+ /* Note: the following can be executed concurrently, so be careful. */
+ printk("\n===================================================\n");
+ printk( "[ INFO: suspicious rcu_dereference_check() usage. ]\n");
+ printk( "---------------------------------------------------\n");
+ printk("%s:%d invoked rcu_dereference_check() without protection!\n",
+ file, line);
+ printk("\nother info that might help us debug this:\n\n");
+ printk("\nrcu_scheduler_active = %d, debug_locks = %d\n", rcu_scheduler_active, debug_locks);
+ lockdep_print_held_locks(curr);
+ printk("\nstack backtrace:\n");
+ dump_stack();
+}
+EXPORT_SYMBOL_GPL(lockdep_rcu_dereference);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff