/* 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 }; #define LOCK_USAGE_READ_MASK 1 #define LOCK_USAGE_DIR_MASK 2 #define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK)) /* * 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 LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE | static const unsigned long LOCKF_ENABLED_IRQ = #include "lockdep_states.h" 0; #undef LOCKDEP_STATE #define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE | static const unsigned long LOCKF_USED_IN_IRQ = #include "lockdep_states.h" 0; #undef LOCKDEP_STATE #define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE##_READ | static const unsigned long LOCKF_ENABLED_IRQ_READ = #include "lockdep_states.h" 0; #undef LOCKDEP_STATE #define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE##_READ | static const unsigned long LOCKF_USED_IN_IRQ_READ = #include "lockdep_states.h" 0; #undef LOCKDEP_STATE #define LOCKF_ENABLED_IRQ_ALL (LOCKF_ENABLED_IRQ | LOCKF_ENABLED_IRQ_READ) #define LOCKF_USED_IN_IRQ_ALL (LOCKF_USED_IN_IRQ | LOCKF_USED_IN_IRQ_READ) #define LOCKF_IRQ (LOCKF_ENABLED_IRQ | LOCKF_USED_IN_IRQ) #define LOCKF_IRQ_READ (LOCKF_ENABLED_IRQ_READ | LOCKF_USED_IN_IRQ_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 #define STACK_TRACE_HASH_SIZE 8192 #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 #define STACK_TRACE_HASH_SIZE 16384 #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(const 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; long lockdep_next_lockchain(long i); unsigned long lock_chain_count(void); 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_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 *); #ifdef CONFIG_TRACE_IRQFLAGS u64 lockdep_stack_trace_count(void); u64 lockdep_stack_hash_count(void); #endif #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 /* * 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 { unsigned long chain_lookup_hits; unsigned int chain_lookup_misses; unsigned long hardirqs_on_events; unsigned long hardirqs_off_events; unsigned long redundant_hardirqs_on; unsigned long redundant_hardirqs_off; unsigned long softirqs_on_events; unsigned long softirqs_off_events; unsigned long redundant_softirqs_on; unsigned long redundant_softirqs_off; int nr_unused_locks; unsigned int nr_redundant_checks; unsigned int nr_redundant; unsigned int nr_cyclic_checks; unsigned int nr_find_usage_forwards_checks; unsigned int nr_find_usage_backwards_checks; /* * 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