lockdep: Comment all warnings (0119fee4) · Commits · e / devices / android_kernel_sony_msm8998

kernel/lockdep.c

+147 −9

Original line number	Diff line number	Diff line
		@@ -96,8 +96,13 @@ static int graph_lock(void)

		static inline int graph_unlock(void)
		{
		if (debug_locks && !arch_spin_is_locked(&lockdep_lock))
		if (debug_locks && !arch_spin_is_locked(&lockdep_lock)) {
		/*
		* The lockdep graph lock isn't locked while we expect it to
		* be, we're confused now, bye!
		*/
		return DEBUG_LOCKS_WARN_ON(1);
		}

		current->lockdep_recursion--;
		arch_spin_unlock(&lockdep_lock);
		@@ -134,6 +139,9 @@ static struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
		static inline struct lock_class hlock_class(struct held_lock hlock)
		{
		if (!hlock->class_idx) {
		/*
		* Someone passed in garbage, we give up.
		*/
		DEBUG_LOCKS_WARN_ON(1);
		return NULL;
		}
		@@ -687,6 +695,10 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
		*/
		list_for_each_entry(class, hash_head, hash_entry) {
		if (class->key == key) {
		/*
		* Huh! same key, different name? Did someone trample
		* on some memory? We're most confused.
		*/
		WARN_ON_ONCE(class->name != lock->name);
		return class;
		}
		@@ -800,6 +812,10 @@ out_unlock_set:
		else if (subclass < NR_LOCKDEP_CACHING_CLASSES)
		lock->class_cache[subclass] = class;

		/*
		* Hash collision, did we smoke some? We found a class with a matching
		* hash but the subclass -- which is hashed in -- didn't match.
		*/
		if (DEBUG_LOCKS_WARN_ON(class->subclass != subclass))
		return NULL;

		@@ -926,7 +942,7 @@ static inline void mark_lock_accessed(struct lock_list *lock,
		unsigned long nr;

		nr = lock - list_entries;
		WARN_ON(nr >= nr_list_entries);
		WARN_ON(nr >= nr_list_entries); /* Out-of-bounds, input fail */
		lock->parent = parent;
		lock->class->dep_gen_id = lockdep_dependency_gen_id;
		}
		@@ -936,7 +952,7 @@ static inline unsigned long lock_accessed(struct lock_list *lock)
		unsigned long nr;

		nr = lock - list_entries;
		WARN_ON(nr >= nr_list_entries);
		WARN_ON(nr >= nr_list_entries); /* Out-of-bounds, input fail */
		return lock->class->dep_gen_id == lockdep_dependency_gen_id;
		}

		@@ -1196,6 +1212,9 @@ static noinline int print_bfs_bug(int ret)
		if (!debug_locks_off_graph_unlock())
		return 0;

		/*
		* Breadth-first-search failed, graph got corrupted?
		*/
		WARN(1, "lockdep bfs error:%d\n", ret);

		return 0;
		@@ -1944,6 +1963,11 @@ out_bug:
		if (!debug_locks_off_graph_unlock())
		return 0;

		/*
		* Clearly we all shouldn't be here, but since we made it we
		* can reliable say we messed up our state. See the above two
		* gotos for reasons why we could possibly end up here.
		*/
		WARN_ON(1);

		return 0;
		@@ -1975,6 +1999,11 @@ static inline int lookup_chain_cache(struct task_struct *curr,
		struct held_lock hlock_curr, hlock_next;
		int i, j;

		/*
		* We might need to take the graph lock, ensure we've got IRQs
		* disabled to make this an IRQ-safe lock.. for recursion reasons
		* lockdep won't complain about its own locking errors.
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return 0;
		/*
		@@ -2126,6 +2155,10 @@ static void check_chain_key(struct task_struct *curr)
		hlock = curr->held_locks + i;
		if (chain_key != hlock->prev_chain_key) {
		debug_locks_off();
		/*
		* We got mighty confused, our chain keys don't match
		* with what we expect, someone trample on our task state?
		*/
		WARN(1, "hm#1, depth: %u [%u], %016Lx != %016Lx\n",
		curr->lockdep_depth, i,
		(unsigned long long)chain_key,
		@@ -2133,6 +2166,9 @@ static void check_chain_key(struct task_struct *curr)
		return;
		}
		id = hlock->class_idx - 1;
		/*
		* Whoops ran out of static storage again?
		*/
		if (DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS))
		return;

		@@ -2144,6 +2180,10 @@ static void check_chain_key(struct task_struct *curr)
		}
		if (chain_key != curr->curr_chain_key) {
		debug_locks_off();
		/*
		* More smoking hash instead of calculating it, damn see these
		* numbers float.. I bet that a pink elephant stepped on my memory.
		*/
		WARN(1, "hm#2, depth: %u [%u], %016Lx != %016Lx\n",
		curr->lockdep_depth, i,
		(unsigned long long)chain_key,
		@@ -2525,12 +2565,24 @@ void trace_hardirqs_on_caller(unsigned long ip)
		return;
		}

		/*
		* We're enabling irqs and according to our state above irqs weren't
		* already enabled, yet we find the hardware thinks they are in fact
		* enabled.. someone messed up their IRQ state tracing.
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return;

		/*
		* See the fine text that goes along with this variable definition.
		*/
		if (DEBUG_LOCKS_WARN_ON(unlikely(early_boot_irqs_disabled)))
		return;

		/*
		* Can't allow enabling interrupts while in an interrupt handler,
		* that's general bad form and such. Recursion, limited stack etc..
		*/
		if (DEBUG_LOCKS_WARN_ON(current->hardirq_context))
		return;

		@@ -2558,6 +2610,10 @@ void trace_hardirqs_off_caller(unsigned long ip)
		if (unlikely(!debug_locks \|\| current->lockdep_recursion))
		return;

		/*
		* So we're supposed to get called after you mask local IRQs, but for
		* some reason the hardware doesn't quite think you did a proper job.
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return;

		@@ -2590,6 +2646,10 @@ void trace_softirqs_on(unsigned long ip)
		if (unlikely(!debug_locks \|\| current->lockdep_recursion))
		return;

		/*
		* We fancy IRQs being disabled here, see softirq.c, avoids
		* funny state and nesting things.
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return;

		@@ -2626,6 +2686,9 @@ void trace_softirqs_off(unsigned long ip)
		if (unlikely(!debug_locks \|\| current->lockdep_recursion))
		return;

		/*
		* We fancy IRQs being disabled here, see softirq.c
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return;

		@@ -2637,6 +2700,9 @@ void trace_softirqs_off(unsigned long ip)
		curr->softirq_disable_ip = ip;
		curr->softirq_disable_event = ++curr->irq_events;
		debug_atomic_inc(softirqs_off_events);
		/*
		* Whoops, we wanted softirqs off, so why aren't they?
		*/
		DEBUG_LOCKS_WARN_ON(!softirq_count());
		} else
		debug_atomic_inc(redundant_softirqs_off);
		@@ -2661,6 +2727,9 @@ static void __lockdep_trace_alloc(gfp_t gfp_mask, unsigned long flags)
		if (!(gfp_mask & __GFP_FS))
		return;

		/*
		* Oi! Can't be having __GFP_FS allocations with IRQs disabled.
		*/
		if (DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags)))
		return;

		@@ -2773,13 +2842,13 @@ static int separate_irq_context(struct task_struct *curr,
		return 0;
		}

		#else
		#else /* defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING) */

		static inline
		int mark_lock_irq(struct task_struct curr, struct held_lock this,
		enum lock_usage_bit new_bit)
		{
		WARN_ON(1);
		WARN_ON(1); /* Impossible innit? when we don't have TRACE_IRQFLAG */
		return 1;
		}

		@@ -2799,7 +2868,7 @@ void lockdep_trace_alloc(gfp_t gfp_mask)
		{
		}

		#endif
		#endif /* defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING) */

		/*
		* Mark a lock with a usage bit, and validate the state transition:
		@@ -2880,6 +2949,9 @@ void lockdep_init_map(struct lockdep_map lock, const char name,
		lock->cpu = raw_smp_processor_id();
		#endif

		/*
		* Can't be having no nameless bastards around this place!
		*/
		if (DEBUG_LOCKS_WARN_ON(!name)) {
		lock->name = "NULL";
		return;
		@@ -2887,6 +2959,9 @@ void lockdep_init_map(struct lockdep_map lock, const char name,

		lock->name = name;

		/*
		* No key, no joy, we need to hash something.
		*/
		if (DEBUG_LOCKS_WARN_ON(!key))
		return;
		/*
		@@ -2894,6 +2969,9 @@ void lockdep_init_map(struct lockdep_map lock, const char name,
		*/
		if (!static_obj(key)) {
		printk("BUG: key %p not in .data!\n", key);
		/*
		* What it says above ^^^^^, I suggest you read it.
		*/
		DEBUG_LOCKS_WARN_ON(1);
		return;
		}
		@@ -2932,6 +3010,11 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
		if (unlikely(!debug_locks))
		return 0;

		/*
		* Lockdep should run with IRQs disabled, otherwise we could
		* get an interrupt which would want to take locks, which would
		* end up in lockdep and have you got a head-ache already?
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return 0;

		@@ -2963,6 +3046,9 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
		* dependency checks are done)
		*/
		depth = curr->lockdep_depth;
		/*
		* Ran out of static storage for our per-task lock stack again have we?
		*/
		if (DEBUG_LOCKS_WARN_ON(depth >= MAX_LOCK_DEPTH))
		return 0;

		@@ -2981,6 +3067,10 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
		}

		hlock = curr->held_locks + depth;
		/*
		* Plain impossible, we just registered it and checked it weren't no
		* NULL like.. I bet this mushroom I ate was good!
		*/
		if (DEBUG_LOCKS_WARN_ON(!class))
		return 0;
		hlock->class_idx = class_idx;
		@@ -3015,11 +3105,17 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
		* the hash, not class->key.
		*/
		id = class - lock_classes;
		/*
		* Whoops, we did it again.. ran straight out of our static allocation.
		*/
		if (DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS))
		return 0;

		chain_key = curr->curr_chain_key;
		if (!depth) {
		/*
		* How can we have a chain hash when we ain't got no keys?!
		*/
		if (DEBUG_LOCKS_WARN_ON(chain_key != 0))
		return 0;
		chain_head = 1;
		@@ -3091,6 +3187,9 @@ static int check_unlock(struct task_struct curr, struct lockdep_map lock,
		{
		if (unlikely(!debug_locks))
		return 0;
		/*
		* Lockdep should run with IRQs disabled, recursion, head-ache, etc..
		*/
		if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
		return 0;

		@@ -3120,6 +3219,11 @@ static int match_held_lock(struct held_lock hlock, struct lockdep_map lock)
		if (!class)
		return 0;

		/*
		* References, but not a lock we're actually ref-counting?
		* State got messed up, follow the sites that change ->references
		* and try to make sense of it.
		*/
		if (DEBUG_LOCKS_WARN_ON(!hlock->nest_lock))
		return 0;

		@@ -3142,6 +3246,10 @@ __lock_set_class(struct lockdep_map lock, const char name,
		int i;

		depth = curr->lockdep_depth;
		/*
		* This function is about (re)setting the class of a held lock,
		* yet we're not actually holding any locks. Naughty user!
		*/
		if (DEBUG_LOCKS_WARN_ON(!depth))
		return 0;

		@@ -3177,6 +3285,10 @@ found_it:
		return 0;
		}

		/*
		* I took it apart and put it back together again, except now I have
		* these 'spare' parts.. where shall I put them.
		*/
		if (DEBUG_LOCKS_WARN_ON(curr->lockdep_depth != depth))
		return 0;
		return 1;
		@@ -3201,6 +3313,10 @@ lock_release_non_nested(struct task_struct *curr,
		* of held locks:
		*/
		depth = curr->lockdep_depth;
		/*
		* So we're all set to release this lock.. wait what lock? We don't
		* own any locks, you've been drinking again?
		*/
		if (DEBUG_LOCKS_WARN_ON(!depth))
		return 0;

		@@ -3253,6 +3369,10 @@ found_it:
		return 0;
		}

		/*
		* We had N bottles of beer on the wall, we drank one, but now
		* there's not N-1 bottles of beer left on the wall...
		*/
		if (DEBUG_LOCKS_WARN_ON(curr->lockdep_depth != depth - 1))
		return 0;
		return 1;
		@@ -3283,6 +3403,9 @@ static int lock_release_nested(struct task_struct *curr,
		return lock_release_non_nested(curr, lock, ip);
		curr->lockdep_depth--;

		/*
		* No more locks, but somehow we've got hash left over, who left it?
		*/
		if (DEBUG_LOCKS_WARN_ON(!depth && (hlock->prev_chain_key != 0)))
		return 0;

		@@ -3365,11 +3488,14 @@ static void check_flags(unsigned long flags)
		* check if not in hardirq contexts:
		*/
		if (!hardirq_count()) {
		if (softirq_count())
		if (softirq_count()) {
		/* like the above, but with softirqs */
		DEBUG_LOCKS_WARN_ON(current->softirqs_enabled);
		else
		} else {
		/* lick the above, does it taste good? */
		DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
		}
		}

		if (!debug_locks)
		print_irqtrace_events(current);
		@@ -3506,6 +3632,10 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
		int i, contention_point, contending_point;

		depth = curr->lockdep_depth;
		/*
		* Whee, we contended on this lock, except it seems we're not
		* actually trying to acquire anything much at all..
		*/
		if (DEBUG_LOCKS_WARN_ON(!depth))
		return;

		@@ -3555,6 +3685,10 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip)
		int i, cpu;

		depth = curr->lockdep_depth;
		/*
		* Yay, we acquired ownership of this lock we didn't try to
		* acquire, how the heck did that happen?
		*/
		if (DEBUG_LOCKS_WARN_ON(!depth))
		return;

		@@ -3759,8 +3893,12 @@ void lockdep_reset_lock(struct lockdep_map *lock)
		match \|= class == lock->class_cache[j];

		if (unlikely(match)) {
		if (debug_locks_off_graph_unlock())
		if (debug_locks_off_graph_unlock()) {
		/*
		* We all just reset everything, how did it match?
		*/
		WARN_ON(1);
		}
		goto out_restore;
		}
		}