blob: 9671e7c4ef0cf81c3e7eeb59e7d55833dec36c16 [file] [log] [blame]
#ifndef __BACKPORT_RCULIST_H
#define __BACKPORT_RCULIST_H
#include_next <linux/rculist.h>
#if LINUX_VERSION_IS_LESS(3,9,0)
#include <backport/magic.h>
#define hlist_for_each_entry_rcu4(tpos, pos, head, member) \
for (pos = rcu_dereference_raw(hlist_first_rcu(head)); \
pos && \
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; });\
pos = rcu_dereference_raw(hlist_next_rcu(pos)))
#define hlist_for_each_entry_rcu3(pos, head, member) \
for (pos = hlist_entry_safe (rcu_dereference_raw(hlist_first_rcu(head)),\
typeof(*(pos)), member); \
pos; \
pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu( \
&(pos)->member)), typeof(*(pos)), member))
#undef hlist_for_each_entry_rcu
#define hlist_for_each_entry_rcu(...) \
macro_dispatcher(hlist_for_each_entry_rcu, __VA_ARGS__)(__VA_ARGS__)
#endif /* < 3.9 */
#ifndef list_for_each_entry_continue_rcu
#define list_for_each_entry_continue_rcu(pos, head, member) \
for (pos = list_entry_rcu(pos->member.next, typeof(*pos), member); \
prefetch(pos->member.next), &pos->member != (head); \
pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
#endif
#ifndef list_entry_rcu
#define list_entry_rcu(ptr, type, member) \
container_of(rcu_dereference(ptr), type, member)
#endif
#ifndef list_first_or_null_rcu
/**
* list_first_or_null_rcu - get the first element from a list
* @ptr: the list head to take the element from.
* @type: the type of the struct this is embedded in.
* @member: the name of the list_struct within the struct.
*
* Note that if the list is empty, it returns NULL.
*
* This primitive may safely run concurrently with the _rcu list-mutation
* primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock().
*/
#define list_first_or_null_rcu(ptr, type, member) \
({ \
struct list_head *__ptr = (ptr); \
struct list_head *__next = ACCESS_ONCE(__ptr->next); \
likely(__ptr != __next) ? list_entry_rcu(__next, type, member) : NULL; \
})
#endif /* list_first_or_null_rcu */
#endif /* __BACKPORT_RCULIST_H */