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Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

Browse Source 
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  lockdep: fix debug_lock_alloc
  lockdep: increase MAX_LOCKDEP_KEYS
  generic-ipi: fix stack and rcu interaction bug in smp_call_function_mask()
  lockdep: fix overflow in the hlock shrinkage code
  lockdep: rename map_[acquire|release]() => lock_map_[acquire|release]()
  lockdep: handle chains involving classes defined in modules
  mm: fix mm_take_all_locks() locking order
  lockdep: annotate mm_take_all_locks()
  lockdep: spin_lock_nest_lock()
  lockdep: lock protection locks
  lockdep: map_acquire
  lockdep: shrink held_lock structure
  lockdep: re-annotate scheduler runqueues
  lockdep: lock_set_subclass - reset a held lock's subclass
  lockdep: change scheduler annotation
  debug_locks: set oops_in_progress if we will log messages.
  lockdep: fix combinatorial explosion in lock subgraph traversal
This commit is contained in:
Linus Torvalds 2008-08-11 16:45:46 -07:00
commit 9b4d0bab32
16 changed files with 413 additions and 153 deletions
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4
fs/jbd/transaction.c
View File

@ -291,7 +291,7 @@ handle_t *journal_start(journal_t *journal, int nblocks)
goto out;
}
lock_acquire(&handle->h_lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_map_acquire(&handle->h_lockdep_map);
out:
return handle;
@ -1448,7 +1448,7 @@ int journal_stop(handle_t *handle)
spin_unlock(&journal->j_state_lock);
}
lock_release(&handle->h_lockdep_map, 1, _THIS_IP_);
lock_map_release(&handle->h_lockdep_map);
jbd_free_handle(handle);
return err;

4
fs/jbd2/transaction.c
View File

@ -301,7 +301,7 @@ handle_t *jbd2_journal_start(journal_t *journal, int nblocks)
goto out;
}
lock_acquire(&handle->h_lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_map_acquire(&handle->h_lockdep_map);
out:
return handle;
}
@ -1279,7 +1279,7 @@ int jbd2_journal_stop(handle_t *handle)
spin_unlock(&journal->j_state_lock);
}
lock_release(&handle->h_lockdep_map, 1, _THIS_IP_);
lock_map_release(&handle->h_lockdep_map);
jbd2_free_handle(handle);
return err;

70
include/linux/lockdep.h
View File

@ -89,6 +89,7 @@ struct lock_class {
struct lockdep_subclass_key *key;
unsigned int subclass;
unsigned int dep_gen_id;
/*
* IRQ/softirq usage tracking bits:
@ -189,6 +190,14 @@ struct lock_chain {
u64 chain_key;
};
#define MAX_LOCKDEP_KEYS_BITS 13
/*
* Subtract one because we offset hlock->class_idx by 1 in order
* to make 0 mean no class. This avoids overflowing the class_idx
* bitfield and hitting the BUG in hlock_class().
*/
#define MAX_LOCKDEP_KEYS ((1UL << MAX_LOCKDEP_KEYS_BITS) - 1)
struct held_lock {
/*
* One-way hash of the dependency chain up to this point. We
@ -205,14 +214,14 @@ struct held_lock {
* with zero), here we store the previous hash value:
*/
u64 prev_chain_key;
struct lock_class *class;
unsigned long acquire_ip;
struct lockdep_map *instance;
struct lockdep_map *nest_lock;
#ifdef CONFIG_LOCK_STAT
u64 waittime_stamp;
u64 holdtime_stamp;
#endif
unsigned int class_idx:MAX_LOCKDEP_KEYS_BITS;
/*
* The lock-stack is unified in that the lock chains of interrupt
* contexts nest ontop of process context chains, but we 'separate'
@ -226,11 +235,11 @@ struct held_lock {
* The following field is used to detect when we cross into an
* interrupt context:
*/
int irq_context;
int trylock;
int read;
int check;
int hardirqs_off;
unsigned int irq_context:2; /* bit 0 - soft, bit 1 - hard */
unsigned int trylock:1;
unsigned int read:2; /* see lock_acquire() comment */
unsigned int check:2; /* see lock_acquire() comment */
unsigned int hardirqs_off:1;
};
/*
@ -294,11 +303,15 @@ extern void lockdep_init_map(struct lockdep_map *lock, const char *name,
* 2: full validation
*/
extern 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,
struct lockdep_map *nest_lock, unsigned long ip);
extern void lock_release(struct lockdep_map *lock, int nested,
unsigned long ip);
extern void lock_set_subclass(struct lockdep_map *lock, unsigned int subclass,
unsigned long ip);
# define INIT_LOCKDEP .lockdep_recursion = 0,
#define lockdep_depth(tsk) (debug_locks ? (tsk)->lockdep_depth : 0)
@ -313,8 +326,9 @@ static inline void lockdep_on(void)
{
}
# define lock_acquire(l, s, t, r, c, i) do { } while (0)
# define lock_acquire(l, s, t, r, c, n, i) do { } while (0)
# define lock_release(l, n, i) do { } while (0)
# define lock_set_subclass(l, s, i) do { } while (0)
# define lockdep_init() do { } while (0)
# define lockdep_info() do { } while (0)
# define lockdep_init_map(lock, name, key, sub) do { (void)(key); } while (0)
@ -400,9 +414,11 @@ static inline void print_irqtrace_events(struct task_struct *curr)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_PROVE_LOCKING
# define spin_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, i)
# define spin_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, NULL, i)
# define spin_acquire_nest(l, s, t, n, i) lock_acquire(l, s, t, 0, 2, n, i)
# else
# define spin_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, i)
# define spin_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, NULL, i)
# define spin_acquire_nest(l, s, t, n, i) lock_acquire(l, s, t, 0, 1, NULL, i)
# endif
# define spin_release(l, n, i) lock_release(l, n, i)
#else
@ -412,11 +428,11 @@ static inline void print_irqtrace_events(struct task_struct *curr)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_PROVE_LOCKING
# define rwlock_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, i)
# define rwlock_acquire_read(l, s, t, i) lock_acquire(l, s, t, 2, 2, i)
# define rwlock_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, NULL, i)
# define rwlock_acquire_read(l, s, t, i) lock_acquire(l, s, t, 2, 2, NULL, i)
# else
# define rwlock_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, i)
# define rwlock_acquire_read(l, s, t, i) lock_acquire(l, s, t, 2, 1, i)
# define rwlock_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, NULL, i)
# define rwlock_acquire_read(l, s, t, i) lock_acquire(l, s, t, 2, 1, NULL, i)
# endif
# define rwlock_release(l, n, i) lock_release(l, n, i)
#else
@ -427,9 +443,9 @@ static inline void print_irqtrace_events(struct task_struct *curr)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_PROVE_LOCKING
# define mutex_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, i)
# define mutex_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, NULL, i)
# else
# define mutex_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, i)
# define mutex_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, NULL, i)
# endif
# define mutex_release(l, n, i) lock_release(l, n, i)
#else
@ -439,11 +455,11 @@ static inline void print_irqtrace_events(struct task_struct *curr)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_PROVE_LOCKING
# define rwsem_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, i)
# define rwsem_acquire_read(l, s, t, i) lock_acquire(l, s, t, 1, 2, i)
# define rwsem_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 2, NULL, i)
# define rwsem_acquire_read(l, s, t, i) lock_acquire(l, s, t, 1, 2, NULL, i)
# else
# define rwsem_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, i)
# define rwsem_acquire_read(l, s, t, i) lock_acquire(l, s, t, 1, 1, i)
# define rwsem_acquire(l, s, t, i) lock_acquire(l, s, t, 0, 1, NULL, i)
# define rwsem_acquire_read(l, s, t, i) lock_acquire(l, s, t, 1, 1, NULL, i)
# endif
# define rwsem_release(l, n, i) lock_release(l, n, i)
#else
@ -452,4 +468,16 @@ static inline void print_irqtrace_events(struct task_struct *curr)
# define rwsem_release(l, n, i) do { } while (0)
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# ifdef CONFIG_PROVE_LOCKING
# define lock_map_acquire(l) lock_acquire(l, 0, 0, 0, 2, NULL, _THIS_IP_)
# else
# define lock_map_acquire(l) lock_acquire(l, 0, 0, 0, 1, NULL, _THIS_IP_)
# endif
# define lock_map_release(l) lock_release(l, 1, _THIS_IP_)
#else
# define lock_map_acquire(l) do { } while (0)
# define lock_map_release(l) do { } while (0)
#endif
#endif /* __LINUX_LOCKDEP_H */

2
include/linux/rcuclassic.h
View File

@ -117,7 +117,7 @@ extern int rcu_needs_cpu(int cpu);
#ifdef CONFIG_DEBUG_LOCK_ALLOC
extern struct lockdep_map rcu_lock_map;
# define rcu_read_acquire() \
lock_acquire(&rcu_lock_map, 0, 0, 2, 1, _THIS_IP_)
lock_acquire(&rcu_lock_map, 0, 0, 2, 1, NULL, _THIS_IP_)
# define rcu_read_release() lock_release(&rcu_lock_map, 1, _THIS_IP_)
#else
# define rcu_read_acquire() do { } while (0)

6
include/linux/spinlock.h
View File

@ -183,8 +183,14 @@ do { \
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define spin_lock_nested(lock, subclass) _spin_lock_nested(lock, subclass)
# define spin_lock_nest_lock(lock, nest_lock) \
do { \
typecheck(struct lockdep_map *, &(nest_lock)->dep_map);\
_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \
} while (0)
#else
# define spin_lock_nested(lock, subclass) _spin_lock(lock)
# define spin_lock_nest_lock(lock, nest_lock) _spin_lock(lock)
#endif
#define write_lock(lock) _write_lock(lock)

2
include/linux/spinlock_api_smp.h
View File

@ -22,6 +22,8 @@ int in_lock_functions(unsigned long addr);
void __lockfunc _spin_lock(spinlock_t *lock) __acquires(lock);
void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass)
__acquires(lock);
void __lockfunc _spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *map)
__acquires(lock);
void __lockfunc _read_lock(rwlock_t *lock) __acquires(lock);
void __lockfunc _write_lock(rwlock_t *lock) __acquires(lock);
void __lockfunc _spin_lock_bh(spinlock_t *lock) __acquires(lock);

295
kernel/lockdep.c
View File

@ -124,6 +124,15 @@ static struct lock_list list_entries[MAX_LOCKDEP_ENTRIES];
unsigned long nr_lock_classes;
static struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
static inline struct lock_class *hlock_class(struct held_lock *hlock)
{
if (!hlock->class_idx) {
DEBUG_LOCKS_WARN_ON(1);
return NULL;
}
return lock_classes + hlock->class_idx - 1;
}
#ifdef CONFIG_LOCK_STAT
static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats);
@ -222,7 +231,7 @@ static void lock_release_holdtime(struct held_lock *hlock)
holdtime = sched_clock() - hlock->holdtime_stamp;
stats = get_lock_stats(hlock->class);
stats = get_lock_stats(hlock_class(hlock));
if (hlock->read)
lock_time_inc(&stats->read_holdtime, holdtime);
else
@ -372,6 +381,19 @@ unsigned int nr_process_chains;
unsigned int max_lockdep_depth;
unsigned int max_recursion_depth;
static unsigned int lockdep_dependency_gen_id;
static bool lockdep_dependency_visit(struct lock_class *source,
unsigned int depth)
{
if (!depth)
lockdep_dependency_gen_id++;
if (source->dep_gen_id == lockdep_dependency_gen_id)
return true;
source->dep_gen_id = lockdep_dependency_gen_id;
return false;
}
#ifdef CONFIG_DEBUG_LOCKDEP
/*
* We cannot printk in early bootup code. Not even early_printk()
@ -505,7 +527,7 @@ static void print_lockdep_cache(struct lockdep_map *lock)
static void print_lock(struct held_lock *hlock)
{
print_lock_name(hlock->class);
print_lock_name(hlock_class(hlock));
printk(", at: ");
print_ip_sym(hlock->acquire_ip);
}
@ -558,6 +580,9 @@ static void print_lock_dependencies(struct lock_class *class, int depth)
{
struct lock_list *entry;
if (lockdep_dependency_visit(class, depth))
return;
if (DEBUG_LOCKS_WARN_ON(depth >= 20))
return;
@ -932,7 +957,7 @@ static noinline int print_circular_bug_tail(void)
if (debug_locks_silent)
return 0;
this.class = check_source->class;
this.class = hlock_class(check_source);
if (!save_trace(&this.trace))
return 0;
@ -959,6 +984,67 @@ static int noinline print_infinite_recursion_bug(void)
return 0;
}
unsigned long __lockdep_count_forward_deps(struct lock_class *class,
unsigned int depth)
{
struct lock_list *entry;
unsigned long ret = 1;
if (lockdep_dependency_visit(class, depth))
return 0;
/*
* Recurse this class's dependency list:
*/
list_for_each_entry(entry, &class->locks_after, entry)
ret += __lockdep_count_forward_deps(entry->class, depth + 1);
return ret;
}
unsigned long lockdep_count_forward_deps(struct lock_class *class)
{
unsigned long ret, flags;
local_irq_save(flags);
__raw_spin_lock(&lockdep_lock);
ret = __lockdep_count_forward_deps(class, 0);
__raw_spin_unlock(&lockdep_lock);
local_irq_restore(flags);
return ret;
}
unsigned long __lockdep_count_backward_deps(struct lock_class *class,
unsigned int depth)
{
struct lock_list *entry;
unsigned long ret = 1;
if (lockdep_dependency_visit(class, depth))
return 0;
/*
* Recurse this class's dependency list:
*/
list_for_each_entry(entry, &class->locks_before, entry)
ret += __lockdep_count_backward_deps(entry->class, depth + 1);
return ret;
}
unsigned long lockdep_count_backward_deps(struct lock_class *class)
{
unsigned long ret, flags;
local_irq_save(flags);
__raw_spin_lock(&lockdep_lock);
ret = __lockdep_count_backward_deps(class, 0);
__raw_spin_unlock(&lockdep_lock);
local_irq_restore(flags);
return ret;
}
/*
* Prove that the dependency graph starting at <entry> can not
* lead to <target>. Print an error and return 0 if it does.
@ -968,6 +1054,9 @@ check_noncircular(struct lock_class *source, unsigned int depth)
{
struct lock_list *entry;
if (lockdep_dependency_visit(source, depth))
return 1;
debug_atomic_inc(&nr_cyclic_check_recursions);
if (depth > max_recursion_depth)
max_recursion_depth = depth;
@ -977,7 +1066,7 @@ check_noncircular(struct lock_class *source, unsigned int depth)
* Check this lock's dependency list:
*/
list_for_each_entry(entry, &source->locks_after, entry) {
if (entry->class == check_target->class)
if (entry->class == hlock_class(check_target))
return print_circular_bug_header(entry, depth+1);
debug_atomic_inc(&nr_cyclic_checks);
if (!check_noncircular(entry->class, depth+1))
@ -1011,6 +1100,9 @@ find_usage_forwards(struct lock_class *source, unsigned int depth)
struct lock_list *entry;
int ret;
if (lockdep_dependency_visit(source, depth))
return 1;
if (depth > max_recursion_depth)
max_recursion_depth = depth;
if (depth >= RECURSION_LIMIT)
@ -1050,6 +1142,9 @@ find_usage_backwards(struct lock_class *source, unsigned int depth)
struct lock_list *entry;
int ret;
if (lockdep_dependency_visit(source, depth))
return 1;
if (!__raw_spin_is_locked(&lockdep_lock))
return DEBUG_LOCKS_WARN_ON(1);
@ -1064,6 +1159,11 @@ find_usage_backwards(struct lock_class *source, unsigned int depth)
return 2;
}
if (!source && debug_locks_off_graph_unlock()) {
WARN_ON(1);
return 0;
}
/*
* Check this lock's dependency list:
*/
@ -1103,9 +1203,9 @@ print_bad_irq_dependency(struct task_struct *curr,
printk("\nand this task is already holding:\n");
print_lock(prev);
printk("which would create a new lock dependency:\n");
print_lock_name(prev->class);
print_lock_name(hlock_class(prev));
printk(" ->");
print_lock_name(next->class);
print_lock_name(hlock_class(next));
printk("\n");
printk("\nbut this new dependency connects a %s-irq-safe lock:\n",
@ -1146,12 +1246,12 @@ check_usage(struct task_struct *curr, struct held_lock *prev,
find_usage_bit = bit_backwards;
/* fills in <backwards_match> */
ret = find_usage_backwards(prev->class, 0);
ret = find_usage_backwards(hlock_class(prev), 0);
if (!ret || ret == 1)
return ret;
find_usage_bit = bit_forwards;
ret = find_usage_forwards(next->class, 0);
ret = find_usage_forwards(hlock_class(next), 0);
if (!ret || ret == 1)
return ret;
/* ret == 2 */
@ -1272,18 +1372,32 @@ check_deadlock(struct task_struct *curr, struct held_lock *next,
struct lockdep_map *next_instance, int read)
{
struct held_lock *prev;
struct held_lock *nest = NULL;
int i;
for (i = 0; i < curr->lockdep_depth; i++) {
prev = curr->held_locks + i;
if (prev->class != next->class)
if (prev->instance == next->nest_lock)
nest = prev;
if (hlock_class(prev) != hlock_class(next))
continue;
/*
* Allow read-after-read recursion of the same
* lock class (i.e. read_lock(lock)+read_lock(lock)):
*/
if ((read == 2) && prev->read)
return 2;
/*
* We're holding the nest_lock, which serializes this lock's
* nesting behaviour.
*/
if (nest)
return 2;
return print_deadlock_bug(curr, prev, next);
}
return 1;
@ -1329,7 +1443,7 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
*/
check_source = next;
check_target = prev;
if (!(check_noncircular(next->class, 0)))
if (!(check_noncircular(hlock_class(next), 0)))
return print_circular_bug_tail();
if (!check_prev_add_irq(curr, prev, next))
@ -1353,8 +1467,8 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
* chains - the second one will be new, but L1 already has
* 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) {
list_for_each_entry(entry, &hlock_class(prev)->locks_after, entry) {
if (entry->class == hlock_class(next)) {
if (distance == 1)
entry->distance = 1;
return 2;
@ -1365,26 +1479,28 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
* Ok, all validations passed, add the new lock
* to the previous lock's dependency list:
*/
ret = add_lock_to_list(prev->class, next->class,
&prev->class->locks_after, next->acquire_ip, distance);
ret = add_lock_to_list(hlock_class(prev), hlock_class(next),
&hlock_class(prev)->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, distance);
ret = add_lock_to_list(hlock_class(next), hlock_class(prev),
&hlock_class(next)->locks_before,
next->acquire_ip, distance);
if (!ret)
return 0;
/*
* Debugging printouts:
*/
if (verbose(prev->class) || verbose(next->class)) {
if (verbose(hlock_class(prev)) || verbose(hlock_class(next))) {
graph_unlock();
printk("\n new dependency: ");
print_lock_name(prev->class);
print_lock_name(hlock_class(prev));
printk(" => ");
print_lock_name(next->class);
print_lock_name(hlock_class(next));
printk("\n");
dump_stack();
return graph_lock();
@ -1481,7 +1597,7 @@ static inline int lookup_chain_cache(struct task_struct *curr,
struct held_lock *hlock,
u64 chain_key)
{
struct lock_class *class = hlock->class;
struct lock_class *class = hlock_class(hlock);
struct list_head *hash_head = chainhashentry(chain_key);
struct lock_chain *chain;
struct held_lock *hlock_curr, *hlock_next;
@ -1554,7 +1670,7 @@ cache_hit:
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;
int lock_id = curr->held_locks[i].class_idx - 1;
chain_hlocks[chain->base + j] = lock_id;
}
chain_hlocks[chain->base + j] = class - lock_classes;
@ -1650,7 +1766,7 @@ static void check_chain_key(struct task_struct *curr)
WARN_ON(1);
return;
}
id = hlock->class - lock_classes;
id = hlock->class_idx - 1;
if (DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS))
return;
@ -1695,7 +1811,7 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this,
print_lock(this);
printk("{%s} state was registered at:\n", usage_str[prev_bit]);
print_stack_trace(this->class->usage_traces + prev_bit, 1);
print_stack_trace(hlock_class(this)->usage_traces + prev_bit, 1);
print_irqtrace_events(curr);
printk("\nother info that might help us debug this:\n");
@ -1714,7 +1830,7 @@ static inline int
valid_state(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit new_bit, enum lock_usage_bit bad_bit)
{
if (unlikely(this->class->usage_mask & (1 << bad_bit)))
if (unlikely(hlock_class(this)->usage_mask & (1 << bad_bit)))
return print_usage_bug(curr, this, bad_bit, new_bit);
return 1;
}
@ -1753,7 +1869,7 @@ print_irq_inversion_bug(struct task_struct *curr, struct lock_class *other,
lockdep_print_held_locks(curr);
printk("\nthe first lock's dependencies:\n");
print_lock_dependencies(this->class, 0);
print_lock_dependencies(hlock_class(this), 0);
printk("\nthe second lock's dependencies:\n");
print_lock_dependencies(other, 0);
@ -1776,7 +1892,7 @@ check_usage_forwards(struct task_struct *curr, struct held_lock *this,
find_usage_bit = bit;
/* fills in <forwards_match> */
ret = find_usage_forwards(this->class, 0);
ret = find_usage_forwards(hlock_class(this), 0);
if (!ret || ret == 1)
return ret;
@ -1795,7 +1911,7 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this,
find_usage_bit = bit;
/* fills in <backwards_match> */
ret = find_usage_backwards(this->class, 0);
ret = find_usage_backwards(hlock_class(this), 0);
if (!ret || ret == 1)
return ret;
@ -1861,7 +1977,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
LOCK_ENABLED_HARDIRQS_READ, "hard-read"))
return 0;
#endif
if (hardirq_verbose(this->class))
if (hardirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_USED_IN_SOFTIRQ:
@ -1886,7 +2002,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
LOCK_ENABLED_SOFTIRQS_READ, "soft-read"))
return 0;
#endif
if (softirq_verbose(this->class))
if (softirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_USED_IN_HARDIRQ_READ:
@ -1899,7 +2015,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
if (!check_usage_forwards(curr, this,
LOCK_ENABLED_HARDIRQS, "hard"))
return 0;
if (hardirq_verbose(this->class))
if (hardirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_USED_IN_SOFTIRQ_READ:
@ -1912,7 +2028,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
if (!check_usage_forwards(curr, this,
LOCK_ENABLED_SOFTIRQS, "soft"))
return 0;
if (softirq_verbose(this->class))
if (softirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_ENABLED_HARDIRQS:
@ -1938,7 +2054,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
LOCK_USED_IN_HARDIRQ_READ, "hard-read"))
return 0;
#endif
if (hardirq_verbose(this->class))
if (hardirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_ENABLED_SOFTIRQS:
@ -1964,7 +2080,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
LOCK_USED_IN_SOFTIRQ_READ, "soft-read"))
return 0;
#endif
if (softirq_verbose(this->class))
if (softirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_ENABLED_HARDIRQS_READ:
@ -1979,7 +2095,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
LOCK_USED_IN_HARDIRQ, "hard"))
return 0;
#endif
if (hardirq_verbose(this->class))
if (hardirq_verbose(hlock_class(this)))
ret = 2;
break;
case LOCK_ENABLED_SOFTIRQS_READ:
@ -1994,7 +2110,7 @@ static int mark_lock_irq(struct task_struct *curr, struct held_lock *this,
LOCK_USED_IN_SOFTIRQ, "soft"))
return 0;
#endif
if (softirq_verbose(this->class))
if (softirq_verbose(hlock_class(this)))
ret = 2;
break;
default:
@ -2310,7 +2426,7 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
* If already set then do not dirty the cacheline,
* nor do any checks:
*/
if (likely(this->class->usage_mask & new_mask))
if (likely(hlock_class(this)->usage_mask & new_mask))
return 1;
if (!graph_lock())
@ -2318,14 +2434,14 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
/*
* Make sure we didnt race:
*/
if (unlikely(this->class->usage_mask & new_mask)) {
if (unlikely(hlock_class(this)->usage_mask & new_mask)) {
graph_unlock();
return 1;
}
this->class->usage_mask |= new_mask;
hlock_class(this)->usage_mask |= new_mask;
if (!save_trace(this->class->usage_traces + new_bit))
if (!save_trace(hlock_class(this)->usage_traces + new_bit))
return 0;
switch (new_bit) {
@ -2405,7 +2521,7 @@ EXPORT_SYMBOL_GPL(lockdep_init_map);
*/
static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
int trylock, int read, int check, int hardirqs_off,
unsigned long ip)
struct lockdep_map *nest_lock, unsigned long ip)
{
struct task_struct *curr = current;
struct lock_class *class = NULL;
@ -2459,10 +2575,12 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
return 0;
hlock = curr->held_locks + depth;
hlock->class = class;
if (DEBUG_LOCKS_WARN_ON(!class))
return 0;
hlock->class_idx = class - lock_classes + 1;
hlock->acquire_ip = ip;
hlock->instance = lock;
hlock->nest_lock = nest_lock;
hlock->trylock = trylock;
hlock->read = read;
hlock->check = check;
@ -2574,6 +2692,55 @@ static int check_unlock(struct task_struct *curr, struct lockdep_map *lock,
return 1;
}
static int
__lock_set_subclass(struct lockdep_map *lock,
unsigned int subclass, unsigned long ip)
{
struct task_struct *curr = current;
struct held_lock *hlock, *prev_hlock;
struct lock_class *class;
unsigned int depth;
int i;
depth = curr->lockdep_depth;
if (DEBUG_LOCKS_WARN_ON(!depth))
return 0;
prev_hlock = NULL;
for (i = depth-1; i >= 0; i--) {
hlock = curr->held_locks + i;
/*
* We must not cross into another context:
*/
if (prev_hlock && prev_hlock->irq_context != hlock->irq_context)
break;
if (hlock->instance == lock)
goto found_it;
prev_hlock = hlock;
}
return print_unlock_inbalance_bug(curr, lock, ip);
found_it:
class = register_lock_class(lock, subclass, 0);
hlock->class_idx = class - lock_classes + 1;
curr->lockdep_depth = i;
curr->curr_chain_key = hlock->prev_chain_key;
for (; i < depth; i++) {
hlock = curr->held_locks + i;
if (!__lock_acquire(hlock->instance,
hlock_class(hlock)->subclass, hlock->trylock,
hlock->read, hlock->check, hlock->hardirqs_off,
hlock->nest_lock, hlock->acquire_ip))
return 0;
}
if (DEBUG_LOCKS_WARN_ON(curr->lockdep_depth != depth))
return 0;
return 1;
}
/*
* Remove the lock to the list of currently held locks in a
* potentially non-nested (out of order) manner. This is a
@ -2624,9 +2791,9 @@ found_it:
for (i++; i < depth; i++) {
hlock = curr->held_locks + i;
if (!__lock_acquire(hlock->instance,
hlock->class->subclass, hlock->trylock,
hlock_class(hlock)->subclass, hlock->trylock,
hlock->read, hlock->check, hlock->hardirqs_off,
hlock->acquire_ip))
hlock->nest_lock, hlock->acquire_ip))
return 0;
}
@ -2669,7 +2836,7 @@ static int lock_release_nested(struct task_struct *curr,
#ifdef CONFIG_DEBUG_LOCKDEP
hlock->prev_chain_key = 0;
hlock->class = NULL;
hlock->class_idx = 0;
hlock->acquire_ip = 0;
hlock->irq_context = 0;
#endif
@ -2738,18 +2905,36 @@ static void check_flags(unsigned long flags)
#endif
}
void
lock_set_subclass(struct lockdep_map *lock,
unsigned int subclass, unsigned long ip)
{
unsigned long flags;
if (unlikely(current->lockdep_recursion))
return;
raw_local_irq_save(flags);
current->lockdep_recursion = 1;
check_flags(flags);
if (__lock_set_subclass(lock, subclass, ip))
check_chain_key(current);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(lock_set_subclass);
/*
* We are not always called with irqs disabled - do that here,
* 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,
struct lockdep_map *nest_lock, unsigned long ip)
{
unsigned long flags;
if (unlikely(!lock_stat && !prove_locking))
return;
if (unlikely(current->lockdep_recursion))
return;
@ -2758,7 +2943,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
current->lockdep_recursion = 1;
__lock_acquire(lock, subclass, trylock, read, check,
irqs_disabled_flags(flags), ip);
irqs_disabled_flags(flags), nest_lock, ip);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
@ -2770,9 +2955,6 @@ void lock_release(struct lockdep_map *lock, int nested,
{
unsigned long flags;
if (unlikely(!lock_stat && !prove_locking))
return;
if (unlikely(current->lockdep_recursion))
return;
@ -2845,9 +3027,9 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
found_it:
hlock->waittime_stamp = sched_clock();
point = lock_contention_point(hlock->class, ip);
point = lock_contention_point(hlock_class(hlock), ip);
stats = get_lock_stats(hlock->class);
stats = get_lock_stats(hlock_class(hlock));
if (point < ARRAY_SIZE(stats->contention_point))
stats->contention_point[i]++;
if (lock->cpu != smp_processor_id())
@ -2893,7 +3075,7 @@ found_it:
hlock->holdtime_stamp = now;
}
stats = get_lock_stats(hlock->class);
stats = get_lock_stats(hlock_class(hlock));
if (waittime) {
if (hlock->read)
lock_time_inc(&stats->read_waittime, waittime);
@ -2988,6 +3170,7 @@ static void zap_class(struct lock_class *class)
list_del_rcu(&class->hash_entry);
list_del_rcu(&class->lock_entry);
class->key = NULL;
}
static inline int within(const void *addr, void *start, unsigned long size)

6
kernel/lockdep_internals.h
View File

@ -17,9 +17,6 @@
*/
#define MAX_LOCKDEP_ENTRIES 8192UL
#define MAX_LOCKDEP_KEYS_BITS 11
#define MAX_LOCKDEP_KEYS (1UL << MAX_LOCKDEP_KEYS_BITS)
#define MAX_LOCKDEP_CHAINS_BITS 14
#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
@ -53,6 +50,9 @@ extern unsigned int nr_process_chains;
extern unsigned int max_lockdep_depth;
extern unsigned int max_recursion_depth;
extern unsigned long lockdep_count_forward_deps(struct lock_class *);
extern unsigned long lockdep_count_backward_deps(struct lock_class *);
#ifdef CONFIG_DEBUG_LOCKDEP
/*
* Various lockdep statistics:

37
kernel/lockdep_proc.c
View File

@ -63,34 +63,6 @@ static void l_stop(struct seq_file *m, void *v)
{
}
static unsigned long count_forward_deps(struct lock_class *class)
{
struct lock_list *entry;
unsigned long ret = 1;
/*
* Recurse this class's dependency list:
*/
list_for_each_entry(entry, &class->locks_after, entry)
ret += count_forward_deps(entry->class);
return ret;
}
static unsigned long count_backward_deps(struct lock_class *class)
{
struct lock_list *entry;
unsigned long ret = 1;
/*
* Recurse this class's dependency list:
*/
list_for_each_entry(entry, &class->locks_before, entry)
ret += count_backward_deps(entry->class);
return ret;
}
static void print_name(struct seq_file *m, struct lock_class *class)
{
char str[128];
@ -124,10 +96,10 @@ static int l_show(struct seq_file *m, void *v)
#ifdef CONFIG_DEBUG_LOCKDEP
seq_printf(m, " OPS:%8ld", class->ops);
#endif
nr_forward_deps = count_forward_deps(class);
nr_forward_deps = lockdep_count_forward_deps(class);
seq_printf(m, " FD:%5ld", nr_forward_deps);
nr_backward_deps = count_backward_deps(class);
nr_backward_deps = lockdep_count_backward_deps(class);
seq_printf(m, " BD:%5ld", nr_backward_deps);
get_usage_chars(class, &c1, &c2, &c3, &c4);
@ -229,6 +201,9 @@ static int lc_show(struct seq_file *m, void *v)
for (i = 0; i < chain->depth; i++) {
class = lock_chain_get_class(chain, i);
if (!class->key)
continue;
seq_printf(m, "[%p] ", class->key);
print_name(m, class);
seq_puts(m, "\n");
@ -350,7 +325,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
if (class->usage_mask & LOCKF_ENABLED_HARDIRQS_READ)
nr_hardirq_read_unsafe++;
sum_forward_deps += count_forward_deps(class);
sum_forward_deps += lockdep_count_forward_deps(class);
}
#ifdef CONFIG_DEBUG_LOCKDEP
DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);

21
kernel/sched.c
View File

@ -600,7 +600,6 @@ struct rq {
/* BKL stats */
unsigned int bkl_count;
#endif
struct lock_class_key rq_lock_key;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
@ -2759,10 +2758,10 @@ static void double_rq_lock(struct rq *rq1, struct rq *rq2)
} else {
if (rq1 < rq2) {
spin_lock(&rq1->lock);
spin_lock(&rq2->lock);
spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
} else {
spin_lock(&rq2->lock);
spin_lock(&rq1->lock);
spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
}
}
update_rq_clock(rq1);
@ -2805,14 +2804,21 @@ static int double_lock_balance(struct rq *this_rq, struct rq *busiest)
if (busiest < this_rq) {
spin_unlock(&this_rq->lock);
spin_lock(&busiest->lock);
spin_lock(&this_rq->lock);
spin_lock_nested(&this_rq->lock, SINGLE_DEPTH_NESTING);
ret = 1;
} else
spin_lock(&busiest->lock);
spin_lock_nested(&busiest->lock, SINGLE_DEPTH_NESTING);
}
return ret;
}
static void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
__releases(busiest->lock)
{
spin_unlock(&busiest->lock);
lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
}
/*
* If dest_cpu is allowed for this process, migrate the task to it.
* This is accomplished by forcing the cpu_allowed mask to only
@ -3637,7 +3643,7 @@ redo:
ld_moved = move_tasks(this_rq, this_cpu, busiest,
imbalance, sd, CPU_NEWLY_IDLE,
&all_pinned);
spin_unlock(&busiest->lock);
double_unlock_balance(this_rq, busiest);
if (unlikely(all_pinned)) {
cpu_clear(cpu_of(busiest), *cpus);
@ -3752,7 +3758,7 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
else
schedstat_inc(sd, alb_failed);
}
spin_unlock(&target_rq->lock);
double_unlock_balance(busiest_rq, target_rq);
}
#ifdef CONFIG_NO_HZ
@ -8000,7 +8006,6 @@ void __init sched_init(void)
rq = cpu_rq(i);
spin_lock_init(&rq->lock);
lockdep_set_class(&rq->lock, &rq->rq_lock_key);
rq->nr_running = 0;
init_cfs_rq(&rq->cfs, rq);
init_rt_rq(&rq->rt, rq);

8
kernel/sched_rt.c
View File

@ -861,6 +861,8 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
#define RT_MAX_TRIES 3
static int double_lock_balance(struct rq *this_rq, struct rq *busiest);
static void double_unlock_balance(struct rq *this_rq, struct rq *busiest);
static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep);
static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
@ -1022,7 +1024,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
break;
/* try again */
spin_unlock(&lowest_rq->lock);
double_unlock_balance(rq, lowest_rq);
lowest_rq = NULL;
}
@ -1091,7 +1093,7 @@ static int push_rt_task(struct rq *rq)
resched_task(lowest_rq->curr);
spin_unlock(&lowest_rq->lock);
double_unlock_balance(rq, lowest_rq);
ret = 1;
out:
@ -1197,7 +1199,7 @@ static int pull_rt_task(struct rq *this_rq)
}
skip:
spin_unlock(&src_rq->lock);
double_unlock_balance(this_rq, src_rq);
}
return ret;

54
kernel/smp.c
View File

@ -260,6 +260,41 @@ void __smp_call_function_single(int cpu, struct call_single_data *data)
generic_exec_single(cpu, data);
}
/* Dummy function */
static void quiesce_dummy(void *unused)
{
}
/*
* Ensure stack based data used in call function mask is safe to free.
*
* This is needed by smp_call_function_mask when using on-stack data, because
* a single call function queue is shared by all CPUs, and any CPU may pick up
* the data item on the queue at any time before it is deleted. So we need to
* ensure that all CPUs have transitioned through a quiescent state after
* this call.
*
* This is a very slow function, implemented by sending synchronous IPIs to
* all possible CPUs. For this reason, we have to alloc data rather than use
* stack based data even in the case of synchronous calls. The stack based
* data is then just used for deadlock/oom fallback which will be very rare.
*
* If a faster scheme can be made, we could go back to preferring stack based
* data -- the data allocation/free is non-zero cost.
*/
static void smp_call_function_mask_quiesce_stack(cpumask_t mask)
{
struct call_single_data data;
int cpu;
data.func = quiesce_dummy;
data.info = NULL;
data.flags = CSD_FLAG_WAIT;
for_each_cpu_mask(cpu, mask)
generic_exec_single(cpu, &data);
}
/**
* smp_call_function_mask(): Run a function on a set of other CPUs.
* @mask: The set of cpus to run on.
@ -285,6 +320,7 @@ int smp_call_function_mask(cpumask_t mask, void (*func)(void *), void *info,
cpumask_t allbutself;
unsigned long flags;
int cpu, num_cpus;
int slowpath = 0;
/* Can deadlock when called with interrupts disabled */
WARN_ON(irqs_disabled());
@ -306,15 +342,16 @@ int smp_call_function_mask(cpumask_t mask, void (*func)(void *), void *info,
return smp_call_function_single(cpu, func, info, wait);
}
if (!wait) {
data = kmalloc(sizeof(*data), GFP_ATOMIC);
if (data)
data->csd.flags = CSD_FLAG_ALLOC;
}
if (!data) {
data = kmalloc(sizeof(*data), GFP_ATOMIC);
if (data) {
data->csd.flags = CSD_FLAG_ALLOC;
if (wait)
data->csd.flags |= CSD_FLAG_WAIT;
} else {
data = &d;
data->csd.flags = CSD_FLAG_WAIT;
wait = 1;
slowpath = 1;
}
spin_lock_init(&data->lock);
@ -331,8 +368,11 @@ int smp_call_function_mask(cpumask_t mask, void (*func)(void *), void *info,
arch_send_call_function_ipi(mask);
/* optionally wait for the CPUs to complete */
if (wait)
if (wait) {
csd_flag_wait(&data->csd);
if (unlikely(slowpath))
smp_call_function_mask_quiesce_stack(allbutself);
}
return 0;
}

11
kernel/spinlock.c
View File

@ -292,6 +292,7 @@ void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass)
}
EXPORT_SYMBOL(_spin_lock_nested);
unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclass)
{
unsigned long flags;
@ -314,6 +315,16 @@ unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclas
EXPORT_SYMBOL(_spin_lock_irqsave_nested);
void __lockfunc _spin_lock_nest_lock(spinlock_t *lock,
struct lockdep_map *nest_lock)
{
preempt_disable();
spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
LOCK_CONTENDED(lock, _raw_spin_trylock, _raw_spin_lock);
}
EXPORT_SYMBOL(_spin_lock_nest_lock);
#endif
void __lockfunc _spin_unlock(spinlock_t *lock)

24
kernel/workqueue.c
View File

@ -290,11 +290,11 @@ static void run_workqueue(struct cpu_workqueue_struct *cwq)
BUG_ON(get_wq_data(work) != cwq);
work_clear_pending(work);
lock_acquire(&cwq->wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_acquire(&lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_map_acquire(&cwq->wq->lockdep_map);
lock_map_acquire(&lockdep_map);
f(work);
lock_release(&lockdep_map, 1, _THIS_IP_);
lock_release(&cwq->wq->lockdep_map, 1, _THIS_IP_);
lock_map_release(&lockdep_map);
lock_map_release(&cwq->wq->lockdep_map);
if (unlikely(in_atomic() || lockdep_depth(current) > 0)) {
printk(KERN_ERR "BUG: workqueue leaked lock or atomic: "
@ -413,8 +413,8 @@ void flush_workqueue(struct workqueue_struct *wq)
int cpu;
might_sleep();
lock_acquire(&wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_release(&wq->lockdep_map, 1, _THIS_IP_);
lock_map_acquire(&wq->lockdep_map);
lock_map_release(&wq->lockdep_map);
for_each_cpu_mask_nr(cpu, *cpu_map)
flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, cpu));
}
@ -441,8 +441,8 @@ int flush_work(struct work_struct *work)
if (!cwq)
return 0;
lock_acquire(&cwq->wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_release(&cwq->wq->lockdep_map, 1, _THIS_IP_);
lock_map_acquire(&cwq->wq->lockdep_map);
lock_map_release(&cwq->wq->lockdep_map);
prev = NULL;
spin_lock_irq(&cwq->lock);
@ -536,8 +536,8 @@ static void wait_on_work(struct work_struct *work)
might_sleep();
lock_acquire(&work->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_release(&work->lockdep_map, 1, _THIS_IP_);
lock_map_acquire(&work->lockdep_map);
lock_map_release(&work->lockdep_map);
cwq = get_wq_data(work);
if (!cwq)
@ -872,8 +872,8 @@ static void cleanup_workqueue_thread(struct cpu_workqueue_struct *cwq)
if (cwq->thread == NULL)
return;
lock_acquire(&cwq->wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
lock_release(&cwq->wq->lockdep_map, 1, _THIS_IP_);
lock_map_acquire(&cwq->wq->lockdep_map);
lock_map_release(&cwq->wq->lockdep_map);
flush_cpu_workqueue(cwq);
/*

2
lib/debug_locks.c
View File

@ -8,6 +8,7 @@
*
* Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*/
#include <linux/kernel.h>
#include <linux/rwsem.h>
#include <linux/mutex.h>
#include <linux/module.h>
@ -37,6 +38,7 @@ int debug_locks_off(void)
{
if (xchg(&debug_locks, 0)) {
if (!debug_locks_silent) {
oops_in_progress = 1;
console_verbose();
return 1;
}

20
mm/mmap.c
View File

@ -2273,14 +2273,14 @@ int install_special_mapping(struct mm_struct *mm,
static DEFINE_MUTEX(mm_all_locks_mutex);
static void vm_lock_anon_vma(struct anon_vma *anon_vma)
static void vm_lock_anon_vma(struct mm_struct *mm, struct anon_vma *anon_vma)
{
if (!test_bit(0, (unsigned long *) &anon_vma->head.next)) {
/*
* The LSB of head.next can't change from under us
* because we hold the mm_all_locks_mutex.
*/
spin_lock(&anon_vma->lock);
spin_lock_nest_lock(&anon_vma->lock, &mm->mmap_sem);
/*
* We can safely modify head.next after taking the
* anon_vma->lock. If some other vma in this mm shares
@ -2296,7 +2296,7 @@ static void vm_lock_anon_vma(struct anon_vma *anon_vma)
}
}
static void vm_lock_mapping(struct address_space *mapping)
static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping)
{
if (!test_bit(AS_MM_ALL_LOCKS, &mapping->flags)) {
/*
@ -2310,7 +2310,7 @@ static void vm_lock_mapping(struct address_space *mapping)
*/
if (test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags))
BUG();
spin_lock(&mapping->i_mmap_lock);
spin_lock_nest_lock(&mapping->i_mmap_lock, &mm->mmap_sem);
}
}
@ -2358,11 +2358,17 @@ int mm_take_all_locks(struct mm_struct *mm)
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (signal_pending(current))
goto out_unlock;
if (vma->anon_vma)
vm_lock_anon_vma(vma->anon_vma);
if (vma->vm_file && vma->vm_file->f_mapping)
vm_lock_mapping(vma->vm_file->f_mapping);
vm_lock_mapping(mm, vma->vm_file->f_mapping);
}
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (signal_pending(current))
goto out_unlock;
if (vma->anon_vma)
vm_lock_anon_vma(mm, vma->anon_vma);
}
ret = 0;
out_unlock: