2 * kernel/lockdep_internals.h
4 * Runtime locking correctness validator
6 * lockdep subsystem internal functions and variables.
10 * Lock-class usage-state bits:
13 #define LOCKDEP_STATE(__STATE) \
14 LOCK_USED_IN_##__STATE, \
15 LOCK_USED_IN_##__STATE##_READ, \
16 LOCK_ENABLED_##__STATE, \
17 LOCK_ENABLED_##__STATE##_READ,
18 #include "lockdep_states.h"
25 * Usage-state bitmasks:
27 #define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
30 #define LOCKDEP_STATE(__STATE) \
31 __LOCKF(USED_IN_##__STATE) \
32 __LOCKF(USED_IN_##__STATE##_READ) \
33 __LOCKF(ENABLED_##__STATE) \
34 __LOCKF(ENABLED_##__STATE##_READ)
35 #include "lockdep_states.h"
40 #define LOCKF_ENABLED_IRQ (LOCKF_ENABLED_HARDIRQ | LOCKF_ENABLED_SOFTIRQ)
41 #define LOCKF_USED_IN_IRQ (LOCKF_USED_IN_HARDIRQ | LOCKF_USED_IN_SOFTIRQ)
43 #define LOCKF_ENABLED_IRQ_READ \
44 (LOCKF_ENABLED_HARDIRQ_READ | LOCKF_ENABLED_SOFTIRQ_READ)
45 #define LOCKF_USED_IN_IRQ_READ \
46 (LOCKF_USED_IN_HARDIRQ_READ | LOCKF_USED_IN_SOFTIRQ_READ)
49 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
52 * We use the per-lock dependency maps in two ways: we grow it by adding
53 * every to-be-taken lock to all currently held lock's own dependency
54 * table (if it's not there yet), and we check it for lock order
55 * conflicts and deadlocks.
57 #define MAX_LOCKDEP_ENTRIES 16384UL
59 #define MAX_LOCKDEP_CHAINS_BITS 15
60 #define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
62 #define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
65 * Stack-trace: tightly packed array of stack backtrace
66 * addresses. Protected by the hash_lock.
68 #define MAX_STACK_TRACE_ENTRIES 262144UL
70 extern struct list_head all_lock_classes
;
71 extern struct lock_chain lock_chains
[];
73 #define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
75 extern void get_usage_chars(struct lock_class
*class,
76 char usage
[LOCK_USAGE_CHARS
]);
78 extern const char * __get_key_name(struct lockdep_subclass_key
*key
, char *str
);
80 struct lock_class
*lock_chain_get_class(struct lock_chain
*chain
, int i
);
82 extern unsigned long nr_lock_classes
;
83 extern unsigned long nr_list_entries
;
84 extern unsigned long nr_lock_chains
;
85 extern int nr_chain_hlocks
;
86 extern unsigned long nr_stack_trace_entries
;
88 extern unsigned int nr_hardirq_chains
;
89 extern unsigned int nr_softirq_chains
;
90 extern unsigned int nr_process_chains
;
91 extern unsigned int max_lockdep_depth
;
92 extern unsigned int max_recursion_depth
;
94 #ifdef CONFIG_PROVE_LOCKING
95 extern unsigned long lockdep_count_forward_deps(struct lock_class
*);
96 extern unsigned long lockdep_count_backward_deps(struct lock_class
*);
98 static inline unsigned long
99 lockdep_count_forward_deps(struct lock_class
*class)
103 static inline unsigned long
104 lockdep_count_backward_deps(struct lock_class
*class)
110 #ifdef CONFIG_DEBUG_LOCKDEP
112 * Various lockdep statistics:
114 extern atomic_t chain_lookup_hits
;
115 extern atomic_t chain_lookup_misses
;
116 extern atomic_t hardirqs_on_events
;
117 extern atomic_t hardirqs_off_events
;
118 extern atomic_t redundant_hardirqs_on
;
119 extern atomic_t redundant_hardirqs_off
;
120 extern atomic_t softirqs_on_events
;
121 extern atomic_t softirqs_off_events
;
122 extern atomic_t redundant_softirqs_on
;
123 extern atomic_t redundant_softirqs_off
;
124 extern atomic_t nr_unused_locks
;
125 extern atomic_t nr_cyclic_checks
;
126 extern atomic_t nr_cyclic_check_recursions
;
127 extern atomic_t nr_find_usage_forwards_checks
;
128 extern atomic_t nr_find_usage_forwards_recursions
;
129 extern atomic_t nr_find_usage_backwards_checks
;
130 extern atomic_t nr_find_usage_backwards_recursions
;
131 # define debug_atomic_inc(ptr) atomic_inc(ptr)
132 # define debug_atomic_dec(ptr) atomic_dec(ptr)
133 # define debug_atomic_read(ptr) atomic_read(ptr)
135 # define debug_atomic_inc(ptr) do { } while (0)
136 # define debug_atomic_dec(ptr) do { } while (0)
137 # define debug_atomic_read(ptr) 0
140 /* The circular_queue and helpers is used to implement the
141 * breadth-first search(BFS)algorithem, by which we can build
142 * the shortest path from the next lock to be acquired to the
143 * previous held lock if there is a circular between them.
145 #define MAX_CIRCULAR_QUE_SIZE 4096UL
146 struct circular_queue
{
147 unsigned long element
[MAX_CIRCULAR_QUE_SIZE
];
148 unsigned int front
, rear
;
151 #define LOCK_ACCESSED 1UL
152 #define LOCK_ACCESSED_MASK (~LOCK_ACCESSED)
154 static inline void __cq_init(struct circular_queue
*cq
)
156 cq
->front
= cq
->rear
= 0;
159 static inline int __cq_empty(struct circular_queue
*cq
)
161 return (cq
->front
== cq
->rear
);
164 static inline int __cq_full(struct circular_queue
*cq
)
166 return ((cq
->rear
+ 1)%MAX_CIRCULAR_QUE_SIZE
) == cq
->front
;
169 static inline int __cq_enqueue(struct circular_queue
*cq
, unsigned long elem
)
174 cq
->element
[cq
->rear
] = elem
;
175 cq
->rear
= (cq
->rear
+ 1)%MAX_CIRCULAR_QUE_SIZE
;
179 static inline int __cq_dequeue(struct circular_queue
*cq
, unsigned long *elem
)
184 *elem
= cq
->element
[cq
->front
];
185 cq
->front
= (cq
->front
+ 1)%MAX_CIRCULAR_QUE_SIZE
;
189 static inline int __cq_get_elem_count(struct circular_queue
*cq
)
191 return (cq
->rear
- cq
->front
)%MAX_CIRCULAR_QUE_SIZE
;
194 static inline void mark_lock_accessed(struct lock_list
*lock
,
195 struct lock_list
*parent
)
197 lock
->parent
= (void *) parent
+ LOCK_ACCESSED
;
200 static inline unsigned long lock_accessed(struct lock_list
*lock
)
202 return (unsigned long)lock
->parent
& LOCK_ACCESSED
;
205 static inline struct lock_list
*get_lock_parent(struct lock_list
*child
)
207 return (struct lock_list
*)
208 ((unsigned long)child
->parent
& LOCK_ACCESSED_MASK
);
211 static inline unsigned long get_lock_depth(struct lock_list
*child
)
213 unsigned long depth
= 0;
214 struct lock_list
*parent
;
216 while ((parent
= get_lock_parent(child
))) {