• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * kernel/lockdep_internals.h
3  *
4  * Runtime locking correctness validator
5  *
6  * lockdep subsystem internal functions and variables.
7  */
8 
9 /*
10  * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
11  * we track.
12  *
13  * We use the per-lock dependency maps in two ways: we grow it by adding
14  * every to-be-taken lock to all currently held lock's own dependency
15  * table (if it's not there yet), and we check it for lock order
16  * conflicts and deadlocks.
17  */
18 #define MAX_LOCKDEP_ENTRIES	8192UL
19 
20 #define MAX_LOCKDEP_CHAINS_BITS	14
21 #define MAX_LOCKDEP_CHAINS	(1UL << MAX_LOCKDEP_CHAINS_BITS)
22 
23 #define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
24 
25 /*
26  * Stack-trace: tightly packed array of stack backtrace
27  * addresses. Protected by the hash_lock.
28  */
29 #define MAX_STACK_TRACE_ENTRIES	262144UL
30 
31 extern struct list_head all_lock_classes;
32 extern struct lock_chain lock_chains[];
33 
34 extern void
35 get_usage_chars(struct lock_class *class, char *c1, char *c2, char *c3, char *c4);
36 
37 extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
38 
39 struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
40 
41 extern unsigned long nr_lock_classes;
42 extern unsigned long nr_list_entries;
43 extern unsigned long nr_lock_chains;
44 extern int nr_chain_hlocks;
45 extern unsigned long nr_stack_trace_entries;
46 
47 extern unsigned int nr_hardirq_chains;
48 extern unsigned int nr_softirq_chains;
49 extern unsigned int nr_process_chains;
50 extern unsigned int max_lockdep_depth;
51 extern unsigned int max_recursion_depth;
52 
53 #ifdef CONFIG_PROVE_LOCKING
54 extern unsigned long lockdep_count_forward_deps(struct lock_class *);
55 extern unsigned long lockdep_count_backward_deps(struct lock_class *);
56 #else
57 static inline unsigned long
lockdep_count_forward_deps(struct lock_class * class)58 lockdep_count_forward_deps(struct lock_class *class)
59 {
60 	return 0;
61 }
62 static inline unsigned long
lockdep_count_backward_deps(struct lock_class * class)63 lockdep_count_backward_deps(struct lock_class *class)
64 {
65 	return 0;
66 }
67 #endif
68 
69 #ifdef CONFIG_DEBUG_LOCKDEP
70 /*
71  * Various lockdep statistics:
72  */
73 extern atomic_t chain_lookup_hits;
74 extern atomic_t chain_lookup_misses;
75 extern atomic_t hardirqs_on_events;
76 extern atomic_t hardirqs_off_events;
77 extern atomic_t redundant_hardirqs_on;
78 extern atomic_t redundant_hardirqs_off;
79 extern atomic_t softirqs_on_events;
80 extern atomic_t softirqs_off_events;
81 extern atomic_t redundant_softirqs_on;
82 extern atomic_t redundant_softirqs_off;
83 extern atomic_t nr_unused_locks;
84 extern atomic_t nr_cyclic_checks;
85 extern atomic_t nr_cyclic_check_recursions;
86 extern atomic_t nr_find_usage_forwards_checks;
87 extern atomic_t nr_find_usage_forwards_recursions;
88 extern atomic_t nr_find_usage_backwards_checks;
89 extern atomic_t nr_find_usage_backwards_recursions;
90 # define debug_atomic_inc(ptr)		atomic_inc(ptr)
91 # define debug_atomic_dec(ptr)		atomic_dec(ptr)
92 # define debug_atomic_read(ptr)		atomic_read(ptr)
93 #else
94 # define debug_atomic_inc(ptr)		do { } while (0)
95 # define debug_atomic_dec(ptr)		do { } while (0)
96 # define debug_atomic_read(ptr)		0
97 #endif
98