1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* kernel/lockdep_internals.h
*
* Runtime locking correctness validator
*
* lockdep subsystem internal functions and variables.
*/
/*
* Lock-class usage-state bits:
*/
enum lock_usage_bit {
#define LOCKDEP_STATE(__STATE) \
LOCK_USED_IN_##__STATE, \
LOCK_USED_IN_##__STATE##_READ, \
LOCK_ENABLED_##__STATE, \
LOCK_ENABLED_##__STATE##_READ,
#include "lockdep_states.h"
#undef LOCKDEP_STATE
LOCK_USED,
LOCK_USAGE_STATES
};
/*
* Usage-state bitmasks:
*/
#define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
enum {
#define LOCKDEP_STATE(__STATE) \
__LOCKF(USED_IN_##__STATE) \
__LOCKF(USED_IN_##__STATE##_READ) \
__LOCKF(ENABLED_##__STATE) \
__LOCKF(ENABLED_##__STATE##_READ)
#include "lockdep_states.h"
#undef LOCKDEP_STATE
__LOCKF(USED)
};
#define LOCKF_ENABLED_IRQ (LOCKF_ENABLED_HARDIRQ | LOCKF_ENABLED_SOFTIRQ)
#define LOCKF_USED_IN_IRQ (LOCKF_USED_IN_HARDIRQ | LOCKF_USED_IN_SOFTIRQ)
#define LOCKF_ENABLED_IRQ_READ \
(LOCKF_ENABLED_HARDIRQ_READ | LOCKF_ENABLED_SOFTIRQ_READ)
#define LOCKF_USED_IN_IRQ_READ \
(LOCKF_USED_IN_HARDIRQ_READ | LOCKF_USED_IN_SOFTIRQ_READ)
/*
* CONFIG_LOCKDEP_SMALL is defined for sparc. Sparc requires .text,
* .data and .bss to fit in required 32MB limit for the kernel. With
* CONFIG_LOCKDEP we could go over this limit and cause system boot-up problems.
* So, reduce the static allocations for lockdeps related structures so that
* everything fits in current required size limit.
*/
#ifdef CONFIG_LOCKDEP_SMALL
/*
* MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
* we track.
*
* We use the per-lock dependency maps in two ways: we grow it by adding
* every to-be-taken lock to all currently held lock's own dependency
* table (if it's not there yet), and we check it for lock order
* conflicts and deadlocks.
*/
#define MAX_LOCKDEP_ENTRIES 16384UL
#define MAX_LOCKDEP_CHAINS_BITS 15
#define MAX_STACK_TRACE_ENTRIES 262144UL
#else
#define MAX_LOCKDEP_ENTRIES 32768UL
#define MAX_LOCKDEP_CHAINS_BITS 16
/*
* Stack-trace: tightly packed array of stack backtrace
* addresses. Protected by the hash_lock.
*/
#define MAX_STACK_TRACE_ENTRIES 524288UL
#endif
#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
extern struct list_head all_lock_classes;
extern struct lock_chain lock_chains[];
#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
extern void get_usage_chars(struct lock_class *class,
char usage[LOCK_USAGE_CHARS]);
extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
extern unsigned long nr_lock_classes;
extern unsigned long nr_list_entries;
extern unsigned long nr_lock_chains;
extern int nr_chain_hlocks;
extern unsigned long nr_stack_trace_entries;
extern unsigned int nr_hardirq_chains;
extern unsigned int nr_softirq_chains;
extern unsigned int nr_process_chains;
extern unsigned int max_lockdep_depth;
extern unsigned int max_recursion_depth;
extern unsigned int max_bfs_queue_depth;
#ifdef CONFIG_PROVE_LOCKING
extern unsigned long lockdep_count_forward_deps(struct lock_class *);
extern unsigned long lockdep_count_backward_deps(struct lock_class *);
#else
static inline unsigned long
lockdep_count_forward_deps(struct lock_class *class)
{
return 0;
}
static inline unsigned long
lockdep_count_backward_deps(struct lock_class *class)
{
return 0;
}
#endif
#ifdef CONFIG_DEBUG_LOCKDEP
#include <asm/local.h>
/*
* Various lockdep statistics.
* We want them per cpu as they are often accessed in fast path
* and we want to avoid too much cache bouncing.
*/
struct lockdep_stats {
int chain_lookup_hits;
int chain_lookup_misses;
int hardirqs_on_events;
int hardirqs_off_events;
int redundant_hardirqs_on;
int redundant_hardirqs_off;
int softirqs_on_events;
int softirqs_off_events;
int redundant_softirqs_on;
int redundant_softirqs_off;
int nr_unused_locks;
int nr_redundant_checks;
int nr_redundant;
int nr_cyclic_checks;
int nr_cyclic_check_recursions;
int nr_find_usage_forwards_checks;
int nr_find_usage_forwards_recursions;
int nr_find_usage_backwards_checks;
int nr_find_usage_backwards_recursions;
/*
* Per lock class locking operation stat counts
*/
unsigned long lock_class_ops[MAX_LOCKDEP_KEYS];
};
DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
#define __debug_atomic_inc(ptr) \
this_cpu_inc(lockdep_stats.ptr);
#define debug_atomic_inc(ptr) { \
WARN_ON_ONCE(!irqs_disabled()); \
__this_cpu_inc(lockdep_stats.ptr); \
}
#define debug_atomic_dec(ptr) { \
WARN_ON_ONCE(!irqs_disabled()); \
__this_cpu_dec(lockdep_stats.ptr); \
}
#define debug_atomic_read(ptr) ({ \
struct lockdep_stats *__cpu_lockdep_stats; \
unsigned long long __total = 0; \
int __cpu; \
for_each_possible_cpu(__cpu) { \
__cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
__total += __cpu_lockdep_stats->ptr; \
} \
__total; \
})
static inline void debug_class_ops_inc(struct lock_class *class)
{
int idx;
idx = class - lock_classes;
__debug_atomic_inc(lock_class_ops[idx]);
}
static inline unsigned long debug_class_ops_read(struct lock_class *class)
{
int idx, cpu;
unsigned long ops = 0;
idx = class - lock_classes;
for_each_possible_cpu(cpu)
ops += per_cpu(lockdep_stats.lock_class_ops[idx], cpu);
return ops;
}
#else
# define __debug_atomic_inc(ptr) do { } while (0)
# define debug_atomic_inc(ptr) do { } while (0)
# define debug_atomic_dec(ptr) do { } while (0)
# define debug_atomic_read(ptr) 0
# define debug_class_ops_inc(ptr) do { } while (0)
#endif
|