Loading...
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 16384UL
58
59#define MAX_LOCKDEP_CHAINS_BITS 15
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 262144UL
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
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_USED_READ,
23 LOCK_USAGE_STATES
24};
25
26#define LOCK_USAGE_READ_MASK 1
27#define LOCK_USAGE_DIR_MASK 2
28#define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK))
29
30/*
31 * Usage-state bitmasks:
32 */
33#define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
34
35enum {
36#define LOCKDEP_STATE(__STATE) \
37 __LOCKF(USED_IN_##__STATE) \
38 __LOCKF(USED_IN_##__STATE##_READ) \
39 __LOCKF(ENABLED_##__STATE) \
40 __LOCKF(ENABLED_##__STATE##_READ)
41#include "lockdep_states.h"
42#undef LOCKDEP_STATE
43 __LOCKF(USED)
44 __LOCKF(USED_READ)
45};
46
47#define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE |
48static const unsigned long LOCKF_ENABLED_IRQ =
49#include "lockdep_states.h"
50 0;
51#undef LOCKDEP_STATE
52
53#define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE |
54static const unsigned long LOCKF_USED_IN_IRQ =
55#include "lockdep_states.h"
56 0;
57#undef LOCKDEP_STATE
58
59#define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE##_READ |
60static const unsigned long LOCKF_ENABLED_IRQ_READ =
61#include "lockdep_states.h"
62 0;
63#undef LOCKDEP_STATE
64
65#define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE##_READ |
66static const unsigned long LOCKF_USED_IN_IRQ_READ =
67#include "lockdep_states.h"
68 0;
69#undef LOCKDEP_STATE
70
71#define LOCKF_ENABLED_IRQ_ALL (LOCKF_ENABLED_IRQ | LOCKF_ENABLED_IRQ_READ)
72#define LOCKF_USED_IN_IRQ_ALL (LOCKF_USED_IN_IRQ | LOCKF_USED_IN_IRQ_READ)
73
74#define LOCKF_IRQ (LOCKF_ENABLED_IRQ | LOCKF_USED_IN_IRQ)
75#define LOCKF_IRQ_READ (LOCKF_ENABLED_IRQ_READ | LOCKF_USED_IN_IRQ_READ)
76
77/*
78 * CONFIG_LOCKDEP_SMALL is defined for sparc. Sparc requires .text,
79 * .data and .bss to fit in required 32MB limit for the kernel. With
80 * CONFIG_LOCKDEP we could go over this limit and cause system boot-up problems.
81 * So, reduce the static allocations for lockdeps related structures so that
82 * everything fits in current required size limit.
83 */
84#ifdef CONFIG_LOCKDEP_SMALL
85/*
86 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
87 * we track.
88 *
89 * We use the per-lock dependency maps in two ways: we grow it by adding
90 * every to-be-taken lock to all currently held lock's own dependency
91 * table (if it's not there yet), and we check it for lock order
92 * conflicts and deadlocks.
93 */
94#define MAX_LOCKDEP_ENTRIES 16384UL
95#define MAX_LOCKDEP_CHAINS_BITS 15
96#define MAX_STACK_TRACE_ENTRIES 262144UL
97#define STACK_TRACE_HASH_SIZE 8192
98#else
99#define MAX_LOCKDEP_ENTRIES 32768UL
100
101#define MAX_LOCKDEP_CHAINS_BITS 16
102
103/*
104 * Stack-trace: tightly packed array of stack backtrace
105 * addresses. Protected by the hash_lock.
106 */
107#define MAX_STACK_TRACE_ENTRIES 524288UL
108#define STACK_TRACE_HASH_SIZE 16384
109#endif
110
111/*
112 * Bit definitions for lock_chain.irq_context
113 */
114#define LOCK_CHAIN_SOFTIRQ_CONTEXT (1 << 0)
115#define LOCK_CHAIN_HARDIRQ_CONTEXT (1 << 1)
116
117#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
118
119#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
120
121extern struct list_head all_lock_classes;
122extern struct lock_chain lock_chains[];
123
124#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
125
126extern void get_usage_chars(struct lock_class *class,
127 char usage[LOCK_USAGE_CHARS]);
128
129extern const char *__get_key_name(const struct lockdep_subclass_key *key,
130 char *str);
131
132struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
133
134extern unsigned long nr_lock_classes;
135extern unsigned long nr_zapped_classes;
136extern unsigned long nr_zapped_lock_chains;
137extern unsigned long nr_list_entries;
138long lockdep_next_lockchain(long i);
139unsigned long lock_chain_count(void);
140extern unsigned long nr_stack_trace_entries;
141
142extern unsigned int nr_hardirq_chains;
143extern unsigned int nr_softirq_chains;
144extern unsigned int nr_process_chains;
145extern unsigned int nr_free_chain_hlocks;
146extern unsigned int nr_lost_chain_hlocks;
147extern unsigned int nr_large_chain_blocks;
148
149extern unsigned int max_lockdep_depth;
150extern unsigned int max_bfs_queue_depth;
151
152#ifdef CONFIG_PROVE_LOCKING
153extern unsigned long lockdep_count_forward_deps(struct lock_class *);
154extern unsigned long lockdep_count_backward_deps(struct lock_class *);
155#ifdef CONFIG_TRACE_IRQFLAGS
156u64 lockdep_stack_trace_count(void);
157u64 lockdep_stack_hash_count(void);
158#endif
159#else
160static inline unsigned long
161lockdep_count_forward_deps(struct lock_class *class)
162{
163 return 0;
164}
165static inline unsigned long
166lockdep_count_backward_deps(struct lock_class *class)
167{
168 return 0;
169}
170#endif
171
172#ifdef CONFIG_DEBUG_LOCKDEP
173
174#include <asm/local.h>
175/*
176 * Various lockdep statistics.
177 * We want them per cpu as they are often accessed in fast path
178 * and we want to avoid too much cache bouncing.
179 */
180struct lockdep_stats {
181 unsigned long chain_lookup_hits;
182 unsigned int chain_lookup_misses;
183 unsigned long hardirqs_on_events;
184 unsigned long hardirqs_off_events;
185 unsigned long redundant_hardirqs_on;
186 unsigned long redundant_hardirqs_off;
187 unsigned long softirqs_on_events;
188 unsigned long softirqs_off_events;
189 unsigned long redundant_softirqs_on;
190 unsigned long redundant_softirqs_off;
191 int nr_unused_locks;
192 unsigned int nr_redundant_checks;
193 unsigned int nr_redundant;
194 unsigned int nr_cyclic_checks;
195 unsigned int nr_find_usage_forwards_checks;
196 unsigned int nr_find_usage_backwards_checks;
197
198 /*
199 * Per lock class locking operation stat counts
200 */
201 unsigned long lock_class_ops[MAX_LOCKDEP_KEYS];
202};
203
204DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
205extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
206
207#define __debug_atomic_inc(ptr) \
208 this_cpu_inc(lockdep_stats.ptr);
209
210#define debug_atomic_inc(ptr) { \
211 WARN_ON_ONCE(!irqs_disabled()); \
212 __this_cpu_inc(lockdep_stats.ptr); \
213}
214
215#define debug_atomic_dec(ptr) { \
216 WARN_ON_ONCE(!irqs_disabled()); \
217 __this_cpu_dec(lockdep_stats.ptr); \
218}
219
220#define debug_atomic_read(ptr) ({ \
221 struct lockdep_stats *__cpu_lockdep_stats; \
222 unsigned long long __total = 0; \
223 int __cpu; \
224 for_each_possible_cpu(__cpu) { \
225 __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
226 __total += __cpu_lockdep_stats->ptr; \
227 } \
228 __total; \
229})
230
231static inline void debug_class_ops_inc(struct lock_class *class)
232{
233 int idx;
234
235 idx = class - lock_classes;
236 __debug_atomic_inc(lock_class_ops[idx]);
237}
238
239static inline unsigned long debug_class_ops_read(struct lock_class *class)
240{
241 int idx, cpu;
242 unsigned long ops = 0;
243
244 idx = class - lock_classes;
245 for_each_possible_cpu(cpu)
246 ops += per_cpu(lockdep_stats.lock_class_ops[idx], cpu);
247 return ops;
248}
249
250#else
251# define __debug_atomic_inc(ptr) do { } while (0)
252# define debug_atomic_inc(ptr) do { } while (0)
253# define debug_atomic_dec(ptr) do { } while (0)
254# define debug_atomic_read(ptr) 0
255# define debug_class_ops_inc(ptr) do { } while (0)
256#endif