diff options
Diffstat (limited to 'ANDROID_3.4.5/include/linux/rculist_nulls.h')
-rw-r--r-- | ANDROID_3.4.5/include/linux/rculist_nulls.h | 116 |
1 files changed, 0 insertions, 116 deletions
diff --git a/ANDROID_3.4.5/include/linux/rculist_nulls.h b/ANDROID_3.4.5/include/linux/rculist_nulls.h deleted file mode 100644 index 2ae13714..00000000 --- a/ANDROID_3.4.5/include/linux/rculist_nulls.h +++ /dev/null @@ -1,116 +0,0 @@ -#ifndef _LINUX_RCULIST_NULLS_H -#define _LINUX_RCULIST_NULLS_H - -#ifdef __KERNEL__ - -/* - * RCU-protected list version - */ -#include <linux/list_nulls.h> -#include <linux/rcupdate.h> - -/** - * hlist_nulls_del_init_rcu - deletes entry from hash list with re-initialization - * @n: the element to delete from the hash list. - * - * Note: hlist_nulls_unhashed() on the node return true after this. It is - * useful for RCU based read lockfree traversal if the writer side - * must know if the list entry is still hashed or already unhashed. - * - * In particular, it means that we can not poison the forward pointers - * that may still be used for walking the hash list and we can only - * zero the pprev pointer so list_unhashed() will return true after - * this. - * - * The caller must take whatever precautions are necessary (such as - * holding appropriate locks) to avoid racing with another - * list-mutation primitive, such as hlist_nulls_add_head_rcu() or - * hlist_nulls_del_rcu(), running on this same list. However, it is - * perfectly legal to run concurrently with the _rcu list-traversal - * primitives, such as hlist_nulls_for_each_entry_rcu(). - */ -static inline void hlist_nulls_del_init_rcu(struct hlist_nulls_node *n) -{ - if (!hlist_nulls_unhashed(n)) { - __hlist_nulls_del(n); - n->pprev = NULL; - } -} - -#define hlist_nulls_first_rcu(head) \ - (*((struct hlist_nulls_node __rcu __force **)&(head)->first)) - -#define hlist_nulls_next_rcu(node) \ - (*((struct hlist_nulls_node __rcu __force **)&(node)->next)) - -/** - * hlist_nulls_del_rcu - deletes entry from hash list without re-initialization - * @n: the element to delete from the hash list. - * - * Note: hlist_nulls_unhashed() on entry does not return true after this, - * the entry is in an undefined state. It is useful for RCU based - * lockfree traversal. - * - * In particular, it means that we can not poison the forward - * pointers that may still be used for walking the hash list. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as hlist_nulls_add_head_rcu() - * or hlist_nulls_del_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * hlist_nulls_for_each_entry(). - */ -static inline void hlist_nulls_del_rcu(struct hlist_nulls_node *n) -{ - __hlist_nulls_del(n); - n->pprev = LIST_POISON2; -} - -/** - * hlist_nulls_add_head_rcu - * @n: the element to add to the hash list. - * @h: the list to add to. - * - * Description: - * Adds the specified element to the specified hlist_nulls, - * while permitting racing traversals. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as hlist_nulls_add_head_rcu() - * or hlist_nulls_del_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * hlist_nulls_for_each_entry_rcu(), used to prevent memory-consistency - * problems on Alpha CPUs. Regardless of the type of CPU, the - * list-traversal primitive must be guarded by rcu_read_lock(). - */ -static inline void hlist_nulls_add_head_rcu(struct hlist_nulls_node *n, - struct hlist_nulls_head *h) -{ - struct hlist_nulls_node *first = h->first; - - n->next = first; - n->pprev = &h->first; - rcu_assign_pointer(hlist_nulls_first_rcu(h), n); - if (!is_a_nulls(first)) - first->pprev = &n->next; -} -/** - * hlist_nulls_for_each_entry_rcu - iterate over rcu list of given type - * @tpos: the type * to use as a loop cursor. - * @pos: the &struct hlist_nulls_node to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the hlist_nulls_node within the struct. - * - */ -#define hlist_nulls_for_each_entry_rcu(tpos, pos, head, member) \ - for (pos = rcu_dereference_raw(hlist_nulls_first_rcu(head)); \ - (!is_a_nulls(pos)) && \ - ({ tpos = hlist_nulls_entry(pos, typeof(*tpos), member); 1; }); \ - pos = rcu_dereference_raw(hlist_nulls_next_rcu(pos))) - -#endif -#endif |