LXR linux/kernel/lockdep

   1/*
   2 * kernel/lockdep_internals.h
   3 *
   4 * Runtime locking correctness validator
   5 *
   6 * lockdep subsystem internal functions and variables.
   7 */
   8
   9/*
  10 * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
  11 * we track.
  12 *
  13 * We use the per-lock dependency maps in two ways: we grow it by adding
  14 * every to-be-taken lock to all currently held lock's own dependency
  15 * table (if it's not there yet), and we check it for lock order
  16 * conflicts and deadlocks.
  17 */
  18#define MAX_LOCKDEP_ENTRIES     8192UL
  19
  20#define MAX_LOCKDEP_CHAINS_BITS 14
  21#define MAX_LOCKDEP_CHAINS      (1UL << MAX_LOCKDEP_CHAINS_BITS)
  22
  23#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
  24
  25/*
  26 * Stack-trace: tightly packed array of stack backtrace
  27 * addresses. Protected by the hash_lock.
  28 */
  29#define MAX_STACK_TRACE_ENTRIES 262144UL
  30
  31extern struct list_head all_lock_classes;
  32extern struct lock_chain lock_chains[];
  33
  34extern void
  35get_usage_chars(struct lock_class *class, char *c1, char *c2, char *c3, char *c4);
  36
  37extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
  38
  39struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
  40
  41extern unsigned long nr_lock_classes;
  42extern unsigned long nr_list_entries;
  43extern unsigned long nr_lock_chains;
  44extern int nr_chain_hlocks;
  45extern unsigned long nr_stack_trace_entries;
  46
  47extern unsigned int nr_hardirq_chains;
  48extern unsigned int nr_softirq_chains;
  49extern unsigned int nr_process_chains;
  50extern unsigned int max_lockdep_depth;
  51extern unsigned int max_recursion_depth;
  52
  53#ifdef CONFIG_PROVE_LOCKING
  54extern unsigned long lockdep_count_forward_deps(struct lock_class *);
  55extern unsigned long lockdep_count_backward_deps(struct lock_class *);
  56#else
  57static inline unsigned long
  58lockdep_count_forward_deps(struct lock_class *class)
  59{
  60        return 0;
  61}
  62static inline unsigned long
  63lockdep_count_backward_deps(struct lock_class *class)
  64{
  65        return 0;
  66}
  67#endif
  68
  69#ifdef CONFIG_DEBUG_LOCKDEP
  70/*
  71 * Various lockdep statistics:
  72 */
  73extern atomic_t chain_lookup_hits;
  74extern atomic_t chain_lookup_misses;
  75extern atomic_t hardirqs_on_events;
  76extern atomic_t hardirqs_off_events;
  77extern atomic_t redundant_hardirqs_on;
  78extern atomic_t redundant_hardirqs_off;
  79extern atomic_t softirqs_on_events;
  80extern atomic_t softirqs_off_events;
  81extern atomic_t redundant_softirqs_on;
  82extern atomic_t redundant_softirqs_off;
  83extern atomic_t nr_unused_locks;
  84extern atomic_t nr_cyclic_checks;
  85extern atomic_t nr_cyclic_check_recursions;
  86extern atomic_t nr_find_usage_forwards_checks;
  87extern atomic_t nr_find_usage_forwards_recursions;
  88extern atomic_t nr_find_usage_backwards_checks;
  89extern atomic_t nr_find_usage_backwards_recursions;
  90# define debug_atomic_inc(ptr)          atomic_inc(ptr)
  91# define debug_atomic_dec(ptr)          atomic_dec(ptr)
  92# define debug_atomic_read(ptr)         atomic_read(ptr)
  93#else
  94# define debug_atomic_inc(ptr)          do { } while (0)
  95# define debug_atomic_dec(ptr)          do { } while (0)
  96# define debug_atomic_read(ptr)         0
  97#endif
  98