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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#define LOCK_USAGE_READ_MASK 1
26#define LOCK_USAGE_DIR_MASK 2
27#define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK))
28
29/*
30 * Usage-state bitmasks:
31 */
32#define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
33
34enum {
35#define LOCKDEP_STATE(__STATE) \
36 __LOCKF(USED_IN_##__STATE) \
37 __LOCKF(USED_IN_##__STATE##_READ) \
38 __LOCKF(ENABLED_##__STATE) \
39 __LOCKF(ENABLED_##__STATE##_READ)
40#include "lockdep_states.h"
41#undef LOCKDEP_STATE
42 __LOCKF(USED)
43};
44
45#define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE |
46static const unsigned long LOCKF_ENABLED_IRQ =
47#include "lockdep_states.h"
48 0;
49#undef LOCKDEP_STATE
50
51#define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE |
52static const unsigned long LOCKF_USED_IN_IRQ =
53#include "lockdep_states.h"
54 0;
55#undef LOCKDEP_STATE
56
57#define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE##_READ |
58static const unsigned long LOCKF_ENABLED_IRQ_READ =
59#include "lockdep_states.h"
60 0;
61#undef LOCKDEP_STATE
62
63#define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE##_READ |
64static const unsigned long LOCKF_USED_IN_IRQ_READ =
65#include "lockdep_states.h"
66 0;
67#undef LOCKDEP_STATE
68
69#define LOCKF_ENABLED_IRQ_ALL (LOCKF_ENABLED_IRQ | LOCKF_ENABLED_IRQ_READ)
70#define LOCKF_USED_IN_IRQ_ALL (LOCKF_USED_IN_IRQ | LOCKF_USED_IN_IRQ_READ)
71
72#define LOCKF_IRQ (LOCKF_ENABLED_IRQ | LOCKF_USED_IN_IRQ)
73#define LOCKF_IRQ_READ (LOCKF_ENABLED_IRQ_READ | LOCKF_USED_IN_IRQ_READ)
74
75/*
76 * CONFIG_LOCKDEP_SMALL is defined for sparc. Sparc requires .text,
77 * .data and .bss to fit in required 32MB limit for the kernel. With
78 * CONFIG_LOCKDEP we could go over this limit and cause system boot-up problems.
79 * So, reduce the static allocations for lockdeps related structures so that
80 * everything fits in current required size limit.
81 */
82#ifdef CONFIG_LOCKDEP_SMALL
83/*
84 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
85 * we track.
86 *
87 * We use the per-lock dependency maps in two ways: we grow it by adding
88 * every to-be-taken lock to all currently held lock's own dependency
89 * table (if it's not there yet), and we check it for lock order
90 * conflicts and deadlocks.
91 */
92#define MAX_LOCKDEP_ENTRIES 16384UL
93#define MAX_LOCKDEP_CHAINS_BITS 15
94#define MAX_STACK_TRACE_ENTRIES 262144UL
95#define STACK_TRACE_HASH_SIZE 8192
96#else
97#define MAX_LOCKDEP_ENTRIES 32768UL
98
99#define MAX_LOCKDEP_CHAINS_BITS 16
100
101/*
102 * Stack-trace: tightly packed array of stack backtrace
103 * addresses. Protected by the hash_lock.
104 */
105#define MAX_STACK_TRACE_ENTRIES 524288UL
106#define STACK_TRACE_HASH_SIZE 16384
107#endif
108
109#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
110
111#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
112
113extern struct list_head all_lock_classes;
114extern struct lock_chain lock_chains[];
115
116#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
117
118extern void get_usage_chars(struct lock_class *class,
119 char usage[LOCK_USAGE_CHARS]);
120
121extern const char *__get_key_name(const struct lockdep_subclass_key *key,
122 char *str);
123
124struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
125
126extern unsigned long nr_lock_classes;
127extern unsigned long nr_list_entries;
128long lockdep_next_lockchain(long i);
129unsigned long lock_chain_count(void);
130extern int nr_chain_hlocks;
131extern unsigned long nr_stack_trace_entries;
132
133extern unsigned int nr_hardirq_chains;
134extern unsigned int nr_softirq_chains;
135extern unsigned int nr_process_chains;
136extern unsigned int max_lockdep_depth;
137
138extern unsigned int max_bfs_queue_depth;
139
140#ifdef CONFIG_PROVE_LOCKING
141extern unsigned long lockdep_count_forward_deps(struct lock_class *);
142extern unsigned long lockdep_count_backward_deps(struct lock_class *);
143#ifdef CONFIG_TRACE_IRQFLAGS
144u64 lockdep_stack_trace_count(void);
145u64 lockdep_stack_hash_count(void);
146#endif
147#else
148static inline unsigned long
149lockdep_count_forward_deps(struct lock_class *class)
150{
151 return 0;
152}
153static inline unsigned long
154lockdep_count_backward_deps(struct lock_class *class)
155{
156 return 0;
157}
158#endif
159
160#ifdef CONFIG_DEBUG_LOCKDEP
161
162#include <asm/local.h>
163/*
164 * Various lockdep statistics.
165 * We want them per cpu as they are often accessed in fast path
166 * and we want to avoid too much cache bouncing.
167 */
168struct lockdep_stats {
169 unsigned long chain_lookup_hits;
170 unsigned int chain_lookup_misses;
171 unsigned long hardirqs_on_events;
172 unsigned long hardirqs_off_events;
173 unsigned long redundant_hardirqs_on;
174 unsigned long redundant_hardirqs_off;
175 unsigned long softirqs_on_events;
176 unsigned long softirqs_off_events;
177 unsigned long redundant_softirqs_on;
178 unsigned long redundant_softirqs_off;
179 int nr_unused_locks;
180 unsigned int nr_redundant_checks;
181 unsigned int nr_redundant;
182 unsigned int nr_cyclic_checks;
183 unsigned int nr_find_usage_forwards_checks;
184 unsigned int nr_find_usage_backwards_checks;
185
186 /*
187 * Per lock class locking operation stat counts
188 */
189 unsigned long lock_class_ops[MAX_LOCKDEP_KEYS];
190};
191
192DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
193extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
194
195#define __debug_atomic_inc(ptr) \
196 this_cpu_inc(lockdep_stats.ptr);
197
198#define debug_atomic_inc(ptr) { \
199 WARN_ON_ONCE(!irqs_disabled()); \
200 __this_cpu_inc(lockdep_stats.ptr); \
201}
202
203#define debug_atomic_dec(ptr) { \
204 WARN_ON_ONCE(!irqs_disabled()); \
205 __this_cpu_dec(lockdep_stats.ptr); \
206}
207
208#define debug_atomic_read(ptr) ({ \
209 struct lockdep_stats *__cpu_lockdep_stats; \
210 unsigned long long __total = 0; \
211 int __cpu; \
212 for_each_possible_cpu(__cpu) { \
213 __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
214 __total += __cpu_lockdep_stats->ptr; \
215 } \
216 __total; \
217})
218
219static inline void debug_class_ops_inc(struct lock_class *class)
220{
221 int idx;
222
223 idx = class - lock_classes;
224 __debug_atomic_inc(lock_class_ops[idx]);
225}
226
227static inline unsigned long debug_class_ops_read(struct lock_class *class)
228{
229 int idx, cpu;
230 unsigned long ops = 0;
231
232 idx = class - lock_classes;
233 for_each_possible_cpu(cpu)
234 ops += per_cpu(lockdep_stats.lock_class_ops[idx], cpu);
235 return ops;
236}
237
238#else
239# define __debug_atomic_inc(ptr) do { } while (0)
240# define debug_atomic_inc(ptr) do { } while (0)
241# define debug_atomic_dec(ptr) do { } while (0)
242# define debug_atomic_read(ptr) 0
243# define debug_class_ops_inc(ptr) do { } while (0)
244#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 * 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
70extern struct list_head all_lock_classes;
71extern struct lock_chain lock_chains[];
72
73#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
74
75extern void get_usage_chars(struct lock_class *class,
76 char usage[LOCK_USAGE_CHARS]);
77
78extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
79
80struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
81
82extern unsigned long nr_lock_classes;
83extern unsigned long nr_list_entries;
84extern unsigned long nr_lock_chains;
85extern int nr_chain_hlocks;
86extern unsigned long nr_stack_trace_entries;
87
88extern unsigned int nr_hardirq_chains;
89extern unsigned int nr_softirq_chains;
90extern unsigned int nr_process_chains;
91extern unsigned int max_lockdep_depth;
92extern unsigned int max_recursion_depth;
93
94extern unsigned int max_bfs_queue_depth;
95
96#ifdef CONFIG_PROVE_LOCKING
97extern unsigned long lockdep_count_forward_deps(struct lock_class *);
98extern unsigned long lockdep_count_backward_deps(struct lock_class *);
99#else
100static inline unsigned long
101lockdep_count_forward_deps(struct lock_class *class)
102{
103 return 0;
104}
105static inline unsigned long
106lockdep_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 */
120struct 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
140DECLARE_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