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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * kernel/lockdep_internals.h
4 *
5 * Runtime locking correctness validator
6 *
7 * lockdep subsystem internal functions and variables.
8 */
9
10/*
11 * Lock-class usage-state bits:
12 */
13enum lock_usage_bit {
14#define LOCKDEP_STATE(__STATE) \
15 LOCK_USED_IN_##__STATE, \
16 LOCK_USED_IN_##__STATE##_READ, \
17 LOCK_ENABLED_##__STATE, \
18 LOCK_ENABLED_##__STATE##_READ,
19#include "lockdep_states.h"
20#undef LOCKDEP_STATE
21 LOCK_USED,
22 LOCK_USAGE_STATES
23};
24
25/*
26 * Usage-state bitmasks:
27 */
28#define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
29
30enum {
31#define LOCKDEP_STATE(__STATE) \
32 __LOCKF(USED_IN_##__STATE) \
33 __LOCKF(USED_IN_##__STATE##_READ) \
34 __LOCKF(ENABLED_##__STATE) \
35 __LOCKF(ENABLED_##__STATE##_READ)
36#include "lockdep_states.h"
37#undef LOCKDEP_STATE
38 __LOCKF(USED)
39};
40
41#define LOCKF_ENABLED_IRQ (LOCKF_ENABLED_HARDIRQ | LOCKF_ENABLED_SOFTIRQ)
42#define LOCKF_USED_IN_IRQ (LOCKF_USED_IN_HARDIRQ | LOCKF_USED_IN_SOFTIRQ)
43
44#define LOCKF_ENABLED_IRQ_READ \
45 (LOCKF_ENABLED_HARDIRQ_READ | LOCKF_ENABLED_SOFTIRQ_READ)
46#define LOCKF_USED_IN_IRQ_READ \
47 (LOCKF_USED_IN_HARDIRQ_READ | LOCKF_USED_IN_SOFTIRQ_READ)
48
49/*
50 * CONFIG_LOCKDEP_SMALL is defined for sparc. Sparc requires .text,
51 * .data and .bss to fit in required 32MB limit for the kernel. With
52 * CONFIG_LOCKDEP we could go over this limit and cause system boot-up problems.
53 * So, reduce the static allocations for lockdeps related structures so that
54 * everything fits in current required size limit.
55 */
56#ifdef CONFIG_LOCKDEP_SMALL
57/*
58 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
59 * we track.
60 *
61 * We use the per-lock dependency maps in two ways: we grow it by adding
62 * every to-be-taken lock to all currently held lock's own dependency
63 * table (if it's not there yet), and we check it for lock order
64 * conflicts and deadlocks.
65 */
66#define MAX_LOCKDEP_ENTRIES 16384UL
67#define MAX_LOCKDEP_CHAINS_BITS 15
68#define MAX_STACK_TRACE_ENTRIES 262144UL
69#else
70#define MAX_LOCKDEP_ENTRIES 32768UL
71
72#define MAX_LOCKDEP_CHAINS_BITS 16
73
74/*
75 * Stack-trace: tightly packed array of stack backtrace
76 * addresses. Protected by the hash_lock.
77 */
78#define MAX_STACK_TRACE_ENTRIES 524288UL
79#endif
80
81#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
82
83#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
84
85extern struct list_head all_lock_classes;
86extern struct lock_chain lock_chains[];
87
88#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
89
90extern void get_usage_chars(struct lock_class *class,
91 char usage[LOCK_USAGE_CHARS]);
92
93extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
94
95struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
96
97extern unsigned long nr_lock_classes;
98extern unsigned long nr_list_entries;
99extern unsigned long nr_lock_chains;
100extern int nr_chain_hlocks;
101extern unsigned long nr_stack_trace_entries;
102
103extern unsigned int nr_hardirq_chains;
104extern unsigned int nr_softirq_chains;
105extern unsigned int nr_process_chains;
106extern unsigned int max_lockdep_depth;
107extern unsigned int max_recursion_depth;
108
109extern unsigned int max_bfs_queue_depth;
110
111#ifdef CONFIG_PROVE_LOCKING
112extern unsigned long lockdep_count_forward_deps(struct lock_class *);
113extern unsigned long lockdep_count_backward_deps(struct lock_class *);
114#else
115static inline unsigned long
116lockdep_count_forward_deps(struct lock_class *class)
117{
118 return 0;
119}
120static inline unsigned long
121lockdep_count_backward_deps(struct lock_class *class)
122{
123 return 0;
124}
125#endif
126
127#ifdef CONFIG_DEBUG_LOCKDEP
128
129#include <asm/local.h>
130/*
131 * Various lockdep statistics.
132 * We want them per cpu as they are often accessed in fast path
133 * and we want to avoid too much cache bouncing.
134 */
135struct lockdep_stats {
136 int chain_lookup_hits;
137 int chain_lookup_misses;
138 int hardirqs_on_events;
139 int hardirqs_off_events;
140 int redundant_hardirqs_on;
141 int redundant_hardirqs_off;
142 int softirqs_on_events;
143 int softirqs_off_events;
144 int redundant_softirqs_on;
145 int redundant_softirqs_off;
146 int nr_unused_locks;
147 int nr_redundant_checks;
148 int nr_redundant;
149 int nr_cyclic_checks;
150 int nr_cyclic_check_recursions;
151 int nr_find_usage_forwards_checks;
152 int nr_find_usage_forwards_recursions;
153 int nr_find_usage_backwards_checks;
154 int nr_find_usage_backwards_recursions;
155};
156
157DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
158
159#define __debug_atomic_inc(ptr) \
160 this_cpu_inc(lockdep_stats.ptr);
161
162#define debug_atomic_inc(ptr) { \
163 WARN_ON_ONCE(!irqs_disabled()); \
164 __this_cpu_inc(lockdep_stats.ptr); \
165}
166
167#define debug_atomic_dec(ptr) { \
168 WARN_ON_ONCE(!irqs_disabled()); \
169 __this_cpu_dec(lockdep_stats.ptr); \
170}
171
172#define debug_atomic_read(ptr) ({ \
173 struct lockdep_stats *__cpu_lockdep_stats; \
174 unsigned long long __total = 0; \
175 int __cpu; \
176 for_each_possible_cpu(__cpu) { \
177 __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
178 __total += __cpu_lockdep_stats->ptr; \
179 } \
180 __total; \
181})
182#else
183# define __debug_atomic_inc(ptr) do { } while (0)
184# define debug_atomic_inc(ptr) do { } while (0)
185# define debug_atomic_dec(ptr) do { } while (0)
186# define debug_atomic_read(ptr) 0
187#endif
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 */
12enum 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
29enum {
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 * CONFIG_PROVE_LOCKING_SMALL is defined for sparc. Sparc requires .text,
50 * .data and .bss to fit in required 32MB limit for the kernel. With
51 * PROVE_LOCKING we could go over this limit and cause system boot-up problems.
52 * So, reduce the static allocations for lockdeps related structures so that
53 * everything fits in current required size limit.
54 */
55#ifdef CONFIG_PROVE_LOCKING_SMALL
56/*
57 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
58 * we track.
59 *
60 * We use the per-lock dependency maps in two ways: we grow it by adding
61 * every to-be-taken lock to all currently held lock's own dependency
62 * table (if it's not there yet), and we check it for lock order
63 * conflicts and deadlocks.
64 */
65#define MAX_LOCKDEP_ENTRIES 16384UL
66#define MAX_LOCKDEP_CHAINS_BITS 15
67#define MAX_STACK_TRACE_ENTRIES 262144UL
68#else
69#define MAX_LOCKDEP_ENTRIES 32768UL
70
71#define MAX_LOCKDEP_CHAINS_BITS 16
72
73/*
74 * Stack-trace: tightly packed array of stack backtrace
75 * addresses. Protected by the hash_lock.
76 */
77#define MAX_STACK_TRACE_ENTRIES 524288UL
78#endif
79
80#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
81
82#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
83
84extern struct list_head all_lock_classes;
85extern struct lock_chain lock_chains[];
86
87#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
88
89extern void get_usage_chars(struct lock_class *class,
90 char usage[LOCK_USAGE_CHARS]);
91
92extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
93
94struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
95
96extern unsigned long nr_lock_classes;
97extern unsigned long nr_list_entries;
98extern unsigned long nr_lock_chains;
99extern int nr_chain_hlocks;
100extern unsigned long nr_stack_trace_entries;
101
102extern unsigned int nr_hardirq_chains;
103extern unsigned int nr_softirq_chains;
104extern unsigned int nr_process_chains;
105extern unsigned int max_lockdep_depth;
106extern unsigned int max_recursion_depth;
107
108extern unsigned int max_bfs_queue_depth;
109
110#ifdef CONFIG_PROVE_LOCKING
111extern unsigned long lockdep_count_forward_deps(struct lock_class *);
112extern unsigned long lockdep_count_backward_deps(struct lock_class *);
113#else
114static inline unsigned long
115lockdep_count_forward_deps(struct lock_class *class)
116{
117 return 0;
118}
119static inline unsigned long
120lockdep_count_backward_deps(struct lock_class *class)
121{
122 return 0;
123}
124#endif
125
126#ifdef CONFIG_DEBUG_LOCKDEP
127
128#include <asm/local.h>
129/*
130 * Various lockdep statistics.
131 * We want them per cpu as they are often accessed in fast path
132 * and we want to avoid too much cache bouncing.
133 */
134struct lockdep_stats {
135 int chain_lookup_hits;
136 int chain_lookup_misses;
137 int hardirqs_on_events;
138 int hardirqs_off_events;
139 int redundant_hardirqs_on;
140 int redundant_hardirqs_off;
141 int softirqs_on_events;
142 int softirqs_off_events;
143 int redundant_softirqs_on;
144 int redundant_softirqs_off;
145 int nr_unused_locks;
146 int nr_cyclic_checks;
147 int nr_cyclic_check_recursions;
148 int nr_find_usage_forwards_checks;
149 int nr_find_usage_forwards_recursions;
150 int nr_find_usage_backwards_checks;
151 int nr_find_usage_backwards_recursions;
152};
153
154DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
155
156#define __debug_atomic_inc(ptr) \
157 this_cpu_inc(lockdep_stats.ptr);
158
159#define debug_atomic_inc(ptr) { \
160 WARN_ON_ONCE(!irqs_disabled()); \
161 __this_cpu_inc(lockdep_stats.ptr); \
162}
163
164#define debug_atomic_dec(ptr) { \
165 WARN_ON_ONCE(!irqs_disabled()); \
166 __this_cpu_dec(lockdep_stats.ptr); \
167}
168
169#define debug_atomic_read(ptr) ({ \
170 struct lockdep_stats *__cpu_lockdep_stats; \
171 unsigned long long __total = 0; \
172 int __cpu; \
173 for_each_possible_cpu(__cpu) { \
174 __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
175 __total += __cpu_lockdep_stats->ptr; \
176 } \
177 __total; \
178})
179#else
180# define __debug_atomic_inc(ptr) do { } while (0)
181# define debug_atomic_inc(ptr) do { } while (0)
182# define debug_atomic_dec(ptr) do { } while (0)
183# define debug_atomic_read(ptr) 0
184#endif