include/linux/rwlock_types.h

root/include/linux/rwlock_types.h
#ifndef __LINUX_RWLOCK_TYPES_H
#define __LINUX_RWLOCK_TYPES_H

#if !defined(__LINUX_SPINLOCK_TYPES_H)
# error "Do not include directly, include spinlock_types.h"
#endif

#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define RW_DEP_MAP_INIT(lockname)                                      \
        .dep_map = {                                                    \
                .name = #lockname,                                      \
                .wait_type_inner = LD_WAIT_CONFIG,                      \
        }
#else
# define RW_DEP_MAP_INIT(lockname)
#endif

#ifndef CONFIG_PREEMPT_RT
/*
 * generic rwlock type definitions and initializers
 *
 * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
 * Released under the General Public License (GPL).
 */
context_lock_struct(rwlock) {
        arch_rwlock_t raw_lock;
#ifdef CONFIG_DEBUG_SPINLOCK
        unsigned int magic, owner_cpu;
        void *owner;
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
        struct lockdep_map dep_map;
#endif
};
typedef struct rwlock rwlock_t;

#define RWLOCK_MAGIC            0xdeaf1eed

#ifdef CONFIG_DEBUG_SPINLOCK
#define __RW_LOCK_UNLOCKED(lockname)                                    \
        (rwlock_t)      {       .raw_lock = __ARCH_RW_LOCK_UNLOCKED,    \
                                .magic = RWLOCK_MAGIC,                  \
                                .owner = SPINLOCK_OWNER_INIT,           \
                                .owner_cpu = -1,                        \
                                RW_DEP_MAP_INIT(lockname) }
#else
#define __RW_LOCK_UNLOCKED(lockname) \
        (rwlock_t)      {       .raw_lock = __ARCH_RW_LOCK_UNLOCKED,    \
                                RW_DEP_MAP_INIT(lockname) }
#endif

#define DEFINE_RWLOCK(x)        rwlock_t x = __RW_LOCK_UNLOCKED(x)

#else /* !CONFIG_PREEMPT_RT */

#include <linux/rwbase_rt.h>

context_lock_struct(rwlock) {
        struct rwbase_rt        rwbase;
        atomic_t                readers;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
        struct lockdep_map      dep_map;
#endif
};
typedef struct rwlock rwlock_t;

#define __RWLOCK_RT_INITIALIZER(name)                                   \
{                                                                       \
        .rwbase = __RWBASE_INITIALIZER(name),                           \
        RW_DEP_MAP_INIT(name)                                           \
}

#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name)

#define DEFINE_RWLOCK(name)                                             \
        rwlock_t name = __RW_LOCK_UNLOCKED(name)

#endif /* CONFIG_PREEMPT_RT */

#endif /* __LINUX_RWLOCK_TYPES_H */
Linux
