--- /dev/null
+/* Copyright (C) 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _LIST_H
+#define _LIST_H 1
+
+/* The definitions of this file are adopted from those which can be
+ found in the Linux kernel headers to enable people familiar with
+ the latter find their way in these sources as well. */
+
+
+/* Basic type for the double-link list. */
+typedef struct list_head
+{
+ struct list_head *next;
+ struct list_head *prev;
+} list_t;
+
+
+/* Define a variable with the head and tail of the list. */
+#define LIST_HEAD(name) \
+ list_t name = { &(name), &(name) }
+
+/* Initialize a new list head. */
+#define INIT_LIST_HEAD(ptr) \
+ (ptr)->next = (ptr)->prev = (ptr)
+
+#define LIST_HEAD_INIT(name) { .prev = &(name), .next = &(name) }
+
+/* Add new element at the head of the list. */
+static inline void
+list_add (list_t *newp, list_t *head)
+{
+ head->next->prev = newp;
+ newp->next = head->next;
+ newp->prev = head;
+ head->next = newp;
+}
+
+
+/* Add new element at the tail of the list. */
+static inline void
+list_add_tail (list_t *newp, list_t *head)
+{
+ head->prev->next = newp;
+ newp->next = head;
+ newp->prev = head->prev;
+ head->prev = newp;
+}
+
+
+/* Remove element from list. */
+static inline void
+list_del (list_t *elem)
+{
+ elem->next->prev = elem->prev;
+ elem->prev->next = elem->next;
+}
+
+
+/* Join two lists. */
+static inline void
+list_splice (list_t *add, list_t *head)
+{
+ /* Do nothing if the list which gets added is empty. */
+ if (add != add->next)
+ {
+ add->next->prev = head;
+ add->prev->next = head->next;
+ head->next->prev = add->prev;
+ head->next = add->next;
+ }
+}
+
+
+/* Get typed element from list at a given position. */
+#define list_entry(ptr, type, member) \
+ ((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member)))
+
+
+
+/* Iterate forward over the elements of the list. */
+#define list_for_each(pos, head) \
+ for (pos = (head)->next; pos != (head); pos = pos->next)
+
+
+/* Iterate forward over the elements of the list. */
+#define list_for_each_prev(pos, head) \
+ for (pos = (head)->prev; pos != (head); pos = pos->prev)
+
+
+/* Iterate backwards over the elements list. The list elements can be
+ removed from the list while doing this. */
+#define list_for_each_prev_safe(pos, p, head) \
+ for (pos = (head)->prev, p = pos->prev; \
+ pos != (head); \
+ pos = p, p = pos->prev)
+
+#define list_for_each_entry(pos, head, member) \
+ for (pos = list_entry((head)->next, typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = list_entry(pos->member.next, typeof(*pos), member))
+
+#define list_for_each_entry_reverse(pos, head, member) \
+ for (pos = list_entry((head)->prev, typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = list_entry(pos->member.prev, typeof(*pos), member))
+
+#define list_for_each_entry_safe(pos, p, head, member) \
+ for (pos = list_entry((head)->next, typeof(*pos), member), \
+ p = list_entry(pos->member.next,typeof(*pos), member); \
+ &pos->member != (head); \
+ pos = p, p = list_entry(pos->member.next, typeof(*pos), member))
+
+static inline int list_empty(list_t *head)
+{
+ return head == head->next;
+}
+
+static inline void list_replace_init(list_t *old,
+ list_t *new)
+{
+ list_t *head = old->next;
+ list_del(old);
+ list_add_tail(new, head);
+ INIT_LIST_HEAD(old);
+}
+
+#endif /* list.h */
--- /dev/null
+#ifndef _KCOMPAT_RCULIST_H
+#define _KCOMPAT_RCULIST_H
+
+/*
+ * RCU-protected list version
+ *
+ * 2002-10-18 19:01:25-07:00, dipankar@in.ibm.com
+ * [PATCH] RCU helper patchset 2/2
+ *
+ * This adds a set of list macros that make handling of list protected
+ * by RCU simpler. The interfaces added are -
+ *
+ * list_add_rcu
+ * list_add_tail_rcu
+ * - Adds an element by taking care of memory barrier (wmb()).
+ *
+ * list_del_rcu
+ * - Deletes an element but doesn't re-initialize the pointers in
+ * the element for supporting RCU based traversal.
+ *
+ * list_for_each_rcu
+ * __list_for_each_rcu
+ * - Traversal of RCU protected list - takes care of memory barriers
+ * transparently.
+ *
+ */
+
+#define _LGPL_SOURCE
+#include <urcu.h>
+#include <kcompat/list.h>
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static __inline__ void __list_add_rcu(struct list_head * new,
+ struct list_head * prev,
+ struct list_head * next)
+{
+ new->next = next;
+ new->prev = prev;
+ smp_wmb();
+ next->prev = new;
+ prev->next = new;
+}
+
+/**
+ * list_add_rcu - add a new entry to rcu-protected list
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as list_add_rcu()
+ * or list_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * list_for_each_entry_rcu().
+ */
+static __inline__ void list_add_rcu(struct list_head *new,
+ struct list_head *head)
+{
+ __list_add_rcu(new, head, head->next);
+}
+
+/**
+ * list_add_tail_rcu - add a new entry to rcu-protected list
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as list_add_tail_rcu()
+ * or list_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * list_for_each_entry_rcu().
+ */
+static __inline__ void list_add_tail_rcu(struct list_head *new,
+ struct list_head *head)
+{
+ __list_add_rcu(new, head->prev, head);
+}
+
+/**
+ * list_del_rcu - deletes entry from list without re-initialization
+ * @entry: the element to delete from the list.
+ *
+ * Note: list_empty on entry does not return true after this,
+ * the entry is in an undefined state. It is useful for RCU based
+ * lockfree traversal.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as list_del_rcu()
+ * or list_add_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * list_for_each_entry_rcu().
+ *
+ * Note that the caller is not permitted to immediately free
+ * the newly deleted entry. Instead, either synchronize_kernel()
+ * or call_rcu() must be used to defer freeing until an RCU
+ * grace period has elapsed.
+ */
+static inline void list_del_rcu(struct list_head *entry)
+{
+ __list_del(entry->prev, entry->next);
+}
+
+/**
+ * list_for_each_rcu - iterate over an rcu-protected list
+ * @pos: the &struct list_head to use as a loop counter.
+ * @head: the head for your list.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as list_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define list_for_each_rcu(pos, head) \
+ for (pos = rcu_dereference((head)->next); \
+ prefetch(pos->next), pos != (head); \
+ pos = rcu_dereference(pos->next))
+
+#define __list_for_each_rcu(pos, head) \
+ for (pos = rcu_dereference((head)->next); \
+ pos != (head); \
+ pos = rcu_dereference(pos->next))
+
+/**
+ * list_for_each_entry_rcu - iterate over a rcu-protected list
+ * @pos: the struct type pointer to use as a loop counter
+ * @head: the head for your list
+ * @member: the name of the struct list_head element in your struct type
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as list_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define list_for_each_entry_rcu(pos, head, member) \
+ for (pos = list_entry(rcu_dereference((head)->next), typeof(*pos), \
+ member); \
+ prefetch(pos->member.next), &pos->member != (head); \
+ pos = list_entry(rcu_dereference(pos->member.next),typeof(*pos), \
+ member))
+
+#endif /* _KCOMPAT_RCULIST_H */
projects / userspace-rcu.git / commitdiff
