LXR linux/include/linux/local_lock

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_LOCAL_LOCK_H
   3# error "Do not include directly, include linux/local_lock.h"
   4#endif
   5
   6#include <linux/percpu-defs.h>
   7#include <linux/lockdep.h>
   8
   9#ifndef CONFIG_PREEMPT_RT
  10
  11typedef struct {
  12#ifdef CONFIG_DEBUG_LOCK_ALLOC
  13        struct lockdep_map      dep_map;
  14        struct task_struct      *owner;
  15#endif
  16} local_lock_t;
  17
  18#ifdef CONFIG_DEBUG_LOCK_ALLOC
  19# define LOCAL_LOCK_DEBUG_INIT(lockname)                \
  20        .dep_map = {                                    \
  21                .name = #lockname,                      \
  22                .wait_type_inner = LD_WAIT_CONFIG,      \
  23                .lock_type = LD_LOCK_PERCPU,            \
  24        },                                              \
  25        .owner = NULL,
  26
  27static inline void local_lock_acquire(local_lock_t *l)
  28{
  29        lock_map_acquire(&l->dep_map);
  30        DEBUG_LOCKS_WARN_ON(l->owner);
  31        l->owner = current;
  32}
  33
  34static inline void local_lock_release(local_lock_t *l)
  35{
  36        DEBUG_LOCKS_WARN_ON(l->owner != current);
  37        l->owner = NULL;
  38        lock_map_release(&l->dep_map);
  39}
  40
  41static inline void local_lock_debug_init(local_lock_t *l)
  42{
  43        l->owner = NULL;
  44}
  45#else /* CONFIG_DEBUG_LOCK_ALLOC */
  46# define LOCAL_LOCK_DEBUG_INIT(lockname)
  47static inline void local_lock_acquire(local_lock_t *l) { }
  48static inline void local_lock_release(local_lock_t *l) { }
  49static inline void local_lock_debug_init(local_lock_t *l) { }
  50#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
  51
  52#define INIT_LOCAL_LOCK(lockname)       { LOCAL_LOCK_DEBUG_INIT(lockname) }
  53
  54#define __local_lock_init(lock)                                 \
  55do {                                                            \
  56        static struct lock_class_key __key;                     \
  57                                                                \
  58        debug_check_no_locks_freed((void *)lock, sizeof(*lock));\
  59        lockdep_init_map_type(&(lock)->dep_map, #lock, &__key,  \
  60                              0, LD_WAIT_CONFIG, LD_WAIT_INV,   \
  61                              LD_LOCK_PERCPU);                  \
  62        local_lock_debug_init(lock);                            \
  63} while (0)
  64
  65#define __local_lock(lock)                                      \
  66        do {                                                    \
  67                preempt_disable();                              \
  68                local_lock_acquire(this_cpu_ptr(lock));         \
  69        } while (0)
  70
  71#define __local_lock_irq(lock)                                  \
  72        do {                                                    \
  73                local_irq_disable();                            \
  74                local_lock_acquire(this_cpu_ptr(lock));         \
  75        } while (0)
  76
  77#define __local_lock_irqsave(lock, flags)                       \
  78        do {                                                    \
  79                local_irq_save(flags);                          \
  80                local_lock_acquire(this_cpu_ptr(lock));         \
  81        } while (0)
  82
  83#define __local_unlock(lock)                                    \
  84        do {                                                    \
  85                local_lock_release(this_cpu_ptr(lock));         \
  86                preempt_enable();                               \
  87        } while (0)
  88
  89#define __local_unlock_irq(lock)                                \
  90        do {                                                    \
  91                local_lock_release(this_cpu_ptr(lock));         \
  92                local_irq_enable();                             \
  93        } while (0)
  94
  95#define __local_unlock_irqrestore(lock, flags)                  \
  96        do {                                                    \
  97                local_lock_release(this_cpu_ptr(lock));         \
  98                local_irq_restore(flags);                       \
  99        } while (0)
 100
 101#else /* !CONFIG_PREEMPT_RT */
 102
 103/*
 104 * On PREEMPT_RT local_lock maps to a per CPU spinlock, which protects the
 105 * critical section while staying preemptible.
 106 */
 107typedef spinlock_t local_lock_t;
 108
 109#define INIT_LOCAL_LOCK(lockname) __LOCAL_SPIN_LOCK_UNLOCKED((lockname))
 110
 111#define __local_lock_init(l)                                    \
 112        do {                                                    \
 113                local_spin_lock_init((l));                      \
 114        } while (0)
 115
 116#define __local_lock(__lock)                                    \
 117        do {                                                    \
 118                migrate_disable();                              \
 119                spin_lock(this_cpu_ptr((__lock)));              \
 120        } while (0)
 121
 122#define __local_lock_irq(lock)                  __local_lock(lock)
 123
 124#define __local_lock_irqsave(lock, flags)                       \
 125        do {                                                    \
 126                typecheck(unsigned long, flags);                \
 127                flags = 0;                                      \
 128                __local_lock(lock);                             \
 129        } while (0)
 130
 131#define __local_unlock(__lock)                                  \
 132        do {                                                    \
 133                spin_unlock(this_cpu_ptr((__lock)));            \
 134                migrate_enable();                               \
 135        } while (0)
 136
 137#define __local_unlock_irq(lock)                __local_unlock(lock)
 138
 139#define __local_unlock_irqrestore(lock, flags)  __local_unlock(lock)
 140
 141#endif /* CONFIG_PREEMPT_RT */
 142