1 /*
2 * kernel/lockdep_internals.h
3 *
4 * Runtime locking correctness validator
5 *
6 * lockdep subsystem internal functions and variables.
7 */
8
9 /*
10 * Lock-class usage-state bits:
11 */
12 enum lock_usage_bit {
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"
19 #undef LOCKDEP_STATE
20 LOCK_USED,
21 LOCK_USAGE_STATES
22 };
23
24 /*
25 * Usage-state bitmasks:
26 */
27 #define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
28
29 enum {
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"
36 #undef LOCKDEP_STATE
37 __LOCKF(USED)
38 };
39
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)
42
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)
47
48 /*
49 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
50 * we track.
51 *
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.
56 */
57 #define MAX_LOCKDEP_ENTRIES 32768UL
58
59 #define MAX_LOCKDEP_CHAINS_BITS 16
60 #define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
61
62 #define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
63
64 /*
65 * Stack-trace: tightly packed array of stack backtrace
66 * addresses. Protected by the hash_lock.
67 */
68 #define MAX_STACK_TRACE_ENTRIES 524288UL
69
70 extern struct list_head all_lock_classes;
71 extern struct lock_chain lock_chains[];
72
73 #define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
74
75 extern void get_usage_chars(struct lock_class *class,
76 char usage[LOCK_USAGE_CHARS]);
77
78 extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
79
80 struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
81
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;
87
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;
93
94 extern unsigned int max_bfs_queue_depth;
95
96 #ifdef CONFIG_PROVE_LOCKING
97 extern unsigned long lockdep_count_forward_deps(struct lock_class *);
98 extern unsigned long lockdep_count_backward_deps(struct lock_class *);
99 #else
100 static inline unsigned long
lockdep_count_forward_deps(struct lock_class * class)101 lockdep_count_forward_deps(struct lock_class *class)
102 {
103 return 0;
104 }
105 static inline unsigned long
lockdep_count_backward_deps(struct lock_class * class)106 lockdep_count_backward_deps(struct lock_class *class)
107 {
108 return 0;
109 }
110 #endif
111
112 #ifdef CONFIG_DEBUG_LOCKDEP
113
114 #include <asm/local.h>
115 /*
116 * Various lockdep statistics.
117 * We want them per cpu as they are often accessed in fast path
118 * and we want to avoid too much cache bouncing.
119 */
120 struct lockdep_stats {
121 int chain_lookup_hits;
122 int chain_lookup_misses;
123 int hardirqs_on_events;
124 int hardirqs_off_events;
125 int redundant_hardirqs_on;
126 int redundant_hardirqs_off;
127 int softirqs_on_events;
128 int softirqs_off_events;
129 int redundant_softirqs_on;
130 int redundant_softirqs_off;
131 int nr_unused_locks;
132 int nr_cyclic_checks;
133 int nr_cyclic_check_recursions;
134 int nr_find_usage_forwards_checks;
135 int nr_find_usage_forwards_recursions;
136 int nr_find_usage_backwards_checks;
137 int nr_find_usage_backwards_recursions;
138 };
139
140 DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
141
142 #define __debug_atomic_inc(ptr) \
143 this_cpu_inc(lockdep_stats.ptr);
144
145 #define debug_atomic_inc(ptr) { \
146 WARN_ON_ONCE(!irqs_disabled()); \
147 __this_cpu_inc(lockdep_stats.ptr); \
148 }
149
150 #define debug_atomic_dec(ptr) { \
151 WARN_ON_ONCE(!irqs_disabled()); \
152 __this_cpu_dec(lockdep_stats.ptr); \
153 }
154
155 #define debug_atomic_read(ptr) ({ \
156 struct lockdep_stats *__cpu_lockdep_stats; \
157 unsigned long long __total = 0; \
158 int __cpu; \
159 for_each_possible_cpu(__cpu) { \
160 __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
161 __total += __cpu_lockdep_stats->ptr; \
162 } \
163 __total; \
164 })
165 #else
166 # define __debug_atomic_inc(ptr) do { } while (0)
167 # define debug_atomic_inc(ptr) do { } while (0)
168 # define debug_atomic_dec(ptr) do { } while (0)
169 # define debug_atomic_read(ptr) 0
170 #endif
171