[git pull] core fixes

Ingo Molnar
2008-08-11T22:20:55Z

Linus,

Please pull the latest core-fixes-for-linus git tree from:

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

90% of the flux comes from lockdep - and most of the fixes are for
long-standing bugs/weaknesses. (like the quadratic overhead bug David
uncovered and fixed)

The only non-strictly bugfix change is:

# f82b217: lockdep: shrink held_lock structure

but Peter wrote and tested/improved that one together with other patches
so i decided against extracting the commit artificially which would have
been pretty invasive.

Thanks,

Ingo

------------------>
Dave Jones (1):
lockdep: shrink held_lock structure

David Miller (2):
lockdep: fix combinatorial explosion in lock subgraph traversal
debug_locks: set oops_in_progress if we will log messages.

Ingo Molnar (2):
lockdep: rename map_[acquire|release]() => lock_map_[acquire|release]()
lockdep: increase MAX_LOCKDEP_KEYS

Nick Piggin (1):
generic-ipi: fix stack and rcu interaction bug in smp_call_function_mask()

Peter Zijlstra (10):
lockdep: change scheduler annotation
lockdep: lock_set_subclass - reset a held lock's subclass
lockdep: re-annotate scheduler runqueues
lockdep: map_acquire
lockdep: lock protection locks
lockdep: spin_lock_nest_lock()
lockdep: annotate mm_take_all_locks()
mm: fix mm_take_all_locks() locking order
lockdep: fix overflow in the hlock shrinkage code
lockdep: fix debug_lock_alloc

Rabin Vincent (1):
lockdep: handle chains involving classes defined in modules

fs/jbd/transaction.c | 4 +-
fs/jbd2/transaction.c | 4 +-
include/linux/lockdep.h | 70 +++++++---
include/linux/rcuclassic.h | 2 +-
include/linux/spinlock.h | 6 +
include/linux/spinlock_api_smp.h | 2 +
kernel/lockdep.c | 295 ++++++++++++++++++++++++++++++-------
kernel/lockdep_internals.h | 6 +-
kernel/lockdep_proc.c | 37 +----
kernel/sched.c | 21 ++-
kernel/sched_rt.c | 8 +-
kernel/smp.c | 54 ++++++-
kernel/spinlock.c | 11 ++
kernel/workqueue.c | 24 ++--
lib/debug_locks.c | 2 +
mm/mmap.c | 20 ++-
16 files changed, 413 insertions(+), 153 deletions(-)

diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 8dee320..0540ca2 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -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;
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 4f7cadb..e5d5405 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -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;
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 2486eb4..331e5f1 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -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 */
diff --git a/include/linux/rcuclassic.h b/include/linux/rcuclassic.h
index 8c77490..4ab8436 100644
--- a/include/linux/rcuclassic.h
+++ b/include/linux/rcuclassic.h
@@ -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)
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 61e5610..e0c0fcc 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -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)
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
index 8a2307c..d79845d 100644
--- a/include/linux/spinlock_api_smp.h
+++ b/include/linux/spinlock_api_smp.h
@@ -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);
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index d38a643..1aa91fd 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -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)
diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h
index c3600a0..55db193 100644
--- a/kernel/lockdep_internals.h
+++ b/kernel/lockdep_internals.h
@@ -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:
diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index 9b0e940..fa19aee 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -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);
diff --git a/kernel/sched.c b/kernel/sched.c
index 04160d2..ace566b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -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);
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 908c04f..6163e4c 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -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;
diff --git a/kernel/smp.c b/kernel/smp.c
index 96fc7c0..e6084f6 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -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;
}
diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index a1fb54c..44baeea 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -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)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 4a26a13..4048e92 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -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);
/*
diff --git a/lib/debug_locks.c b/lib/debug_locks.c
index 0ef01d1..0218b46 100644
--- a/lib/debug_locks.c
+++ b/lib/debug_locks.c
@@ -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;
}
diff --git a/mm/mmap.c b/mm/mmap.c
index 971d0ed..339cf5c 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -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;