kernel_optimize_test/kernel/locking/lockdep_internals.h
Frederic Weisbecker bba2a8f1f9 locking/lockdep: Provide enum lock_usage_bit mask names
It makes the code more self-explanatory and tells throughout the code
what magic number refers to:

 - state (Hardirq/Softirq)
 - direction (used in or enabled above state)
 - read or write

We can even remove some comments that were compensating for the lack of
those constant names.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/1545973321-24422-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:56 +01:00

219 lines
5.8 KiB
C

/* 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 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