kernel/locking/lockdep_internals.h

   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     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
  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
 101 lockdep_count_forward_deps(struct lock_class *class)
 102 {
 103         return 0;
 104 }
 105 static inline unsigned long
 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