[PATCH 1/2] Split list.h and move rcu-protected lists into rculist.h

From: Franck Bui-Huu
Date: Wed May 14 2008 - 17:25:39 EST

From: Franck Bui-Huu <fbuihuu@xxxxxxxxx>

This patch moves rcu-protected lists from list.h into a new header
file rculist.h.

This is done because list are a very used primitive structure all over
the kernel and it's currently impossible to include other header files
in this list.h without creating some circular dependencies.

For example, list.h implements rcu-protected list and uses
rcu_dereference() without including rcupdate.h. It actually compiles
because users of rcu_dereference() are macros. Others RCU functions
could be used too but aren't probably because of this.

Therefore this patch creates rculist.h which includes rcupdates
without to many changes/troubles.

Signed-off-by: Franck Bui-Huu <fbuihuu@xxxxxxxxx>
---

Andrew,

This has been rebased on v2.6.26-rc2-mm1.

allmodconfig target compiles fine.

Franck

arch/ia64/sn/kernel/irq.c | 1 +
arch/x86/mm/kmmio.c | 2 +-
crypto/async_tx/async_tx.c | 1 +
drivers/infiniband/hw/ipath/ipath_verbs.c | 1 +
drivers/infiniband/hw/ipath/ipath_verbs_mcast.c | 3 +-
drivers/net/macvlan.c | 2 +-
include/linux/dcache.h | 1 +
include/linux/list.h | 367 ----------------------
include/linux/rculist.h | 375 +++++++++++++++++++++++
kernel/pid.c | 1 +
lib/textsearch.c | 1 +
net/802/psnap.c | 1 +
net/8021q/vlan.c | 1 +
net/bridge/br_fdb.c | 1 +
net/bridge/br_stp.c | 1 +
net/netlabel/netlabel_domainhash.c | 3 +-
16 files changed, 389 insertions(+), 373 deletions(-)
create mode 100644 include/linux/rculist.h

diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
index 53351c3..96c31b4 100644
--- a/arch/ia64/sn/kernel/irq.c
+++ b/arch/ia64/sn/kernel/irq.c
@@ -11,6 +11,7 @@
#include <linux/irq.h>
#include <linux/spinlock.h>
#include <linux/init.h>
+#include <linux/rculist.h>
#include <asm/sn/addrs.h>
#include <asm/sn/arch.h>
#include <asm/sn/intr.h>
diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c
index 93b1797..82d40a6 100644
--- a/arch/x86/mm/kmmio.c
+++ b/arch/x86/mm/kmmio.c
@@ -5,7 +5,7 @@
* 2008 Pekka Paalanen <pq@xxxxxx>
*/

-#include <linux/list.h>
+#include <linux/rculist.h>
#include <linux/spinlock.h>
#include <linux/hash.h>
#include <linux/init.h>
diff --git a/crypto/async_tx/async_tx.c b/crypto/async_tx/async_tx.c
index c6e772f..095c798 100644
--- a/crypto/async_tx/async_tx.c
+++ b/crypto/async_tx/async_tx.c
@@ -23,6 +23,7 @@
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
+#include <linux/rculist.h>
#include <linux/kernel.h>
#include <linux/async_tx.h>

diff --git a/drivers/infiniband/hw/ipath/ipath_verbs.c b/drivers/infiniband/hw/ipath/ipath_verbs.c
index 5015cd2..36d96d3 100644
--- a/drivers/infiniband/hw/ipath/ipath_verbs.c
+++ b/drivers/infiniband/hw/ipath/ipath_verbs.c
@@ -35,6 +35,7 @@
#include <rdma/ib_user_verbs.h>
#include <linux/io.h>
#include <linux/utsname.h>
+#include <linux/rculist.h>

#include "ipath_kernel.h"
#include "ipath_verbs.h"
diff --git a/drivers/infiniband/hw/ipath/ipath_verbs_mcast.c b/drivers/infiniband/hw/ipath/ipath_verbs_mcast.c
index 9e5abf9..d73e322 100644
--- a/drivers/infiniband/hw/ipath/ipath_verbs_mcast.c
+++ b/drivers/infiniband/hw/ipath/ipath_verbs_mcast.c
@@ -31,8 +31,7 @@
* SOFTWARE.
*/

-#include <linux/list.h>
-#include <linux/rcupdate.h>
+#include <linux/rculist.h>

#include "ipath_verbs.h"

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index c36a03a..860d75d 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -20,7 +20,7 @@
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
-#include <linux/list.h>
+#include <linux/rculist.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index d982eb8..98202c6 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -3,6 +3,7 @@

#include <asm/atomic.h>
#include <linux/list.h>
+#include <linux/rculist.h>
#include <linux/spinlock.h>
#include <linux/cache.h>
#include <linux/rcupdate.h>
diff --git a/include/linux/list.h b/include/linux/list.h
index 13ecd42..453916b 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -81,65 +81,6 @@ static inline void list_add_tail(struct list_head *new, struct list_head *head)
}

/*
- * 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);
-}
-
-/*
* Delete a list entry by making the prev/next entries
* point to each other.
*
@@ -170,36 +111,6 @@ extern void list_del(struct list_head *entry);
#endif

/**
- * 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.
- *
- * In particular, it means that we can not poison the forward
- * pointers that may still be used for walking the list.
- *
- * 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_rcu()
- * 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);
- entry->prev = LIST_POISON2;
-}
-
-/**
* list_replace - replace old entry by new one
* @old : the element to be replaced
* @new : the new element to insert
@@ -223,25 +134,6 @@ static inline void list_replace_init(struct list_head *old,
}

/**
- * list_replace_rcu - replace old entry by new one
- * @old : the element to be replaced
- * @new : the new element to insert
- *
- * The @old entry will be replaced with the @new entry atomically.
- * Note: @old should not be empty.
- */
-static inline void list_replace_rcu(struct list_head *old,
- struct list_head *new)
-{
- new->next = old->next;
- new->prev = old->prev;
- smp_wmb();
- new->next->prev = new;
- new->prev->next = new;
- old->prev = LIST_POISON2;
-}
-
-/**
* list_del_init - deletes entry from list and reinitialize it.
* @entry: the element to delete from the list.
*/
@@ -365,62 +257,6 @@ static inline void list_splice_init(struct list_head *list,
}

/**
- * list_splice_init_rcu - splice an RCU-protected list into an existing list.
- * @list: the RCU-protected list to splice
- * @head: the place in the list to splice the first list into
- * @sync: function to sync: synchronize_rcu(), synchronize_sched(), ...
- *
- * @head can be RCU-read traversed concurrently with this function.
- *
- * Note that this function blocks.
- *
- * Important note: the caller must take whatever action is necessary to
- * prevent any other updates to @head. In principle, it is possible
- * to modify the list as soon as sync() begins execution.
- * If this sort of thing becomes necessary, an alternative version
- * based on call_rcu() could be created. But only if -really-
- * needed -- there is no shortage of RCU API members.
- */
-static inline void list_splice_init_rcu(struct list_head *list,
- struct list_head *head,
- void (*sync)(void))
-{
- struct list_head *first = list->next;
- struct list_head *last = list->prev;
- struct list_head *at = head->next;
-
- if (list_empty(head))
- return;
-
- /* "first" and "last" tracking list, so initialize it. */
-
- INIT_LIST_HEAD(list);
-
- /*
- * At this point, the list body still points to the source list.
- * Wait for any readers to finish using the list before splicing
- * the list body into the new list. Any new readers will see
- * an empty list.
- */
-
- sync();
-
- /*
- * Readers are finished with the source list, so perform splice.
- * The order is important if the new list is global and accessible
- * to concurrent RCU readers. Note that RCU readers are not
- * permitted to traverse the prev pointers without excluding
- * this function.
- */
-
- last->next = at;
- smp_wmb();
- head->next = first;
- first->prev = head;
- at->prev = last;
-}
-
-/**
* list_entry - get the struct for this entry
* @ptr: the &struct list_head pointer.
* @type: the type of the struct this is embedded in.
@@ -625,57 +461,6 @@ static inline void list_splice_init_rcu(struct list_head *list,
&pos->member != (head); \
pos = n, n = list_entry(n->member.prev, typeof(*n), member))

-/**
- * list_for_each_rcu - iterate over an rcu-protected list
- * @pos: the &struct list_head to use as a loop cursor.
- * @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 rcu list of given type
- * @pos: the type * to use as a loop cursor.
- * @head: the head for your list.
- * @member: the name of the list_struct within the struct.
- *
- * 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))
-
-
-/**
- * list_for_each_continue_rcu
- * @pos: the &struct list_head to use as a loop cursor.
- * @head: the head for your list.
- *
- * Iterate over an rcu-protected list, continuing after current point.
- *
- * 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_continue_rcu(pos, head) \
- for ((pos) = rcu_dereference((pos)->next); \
- prefetch((pos)->next), (pos) != (head); \
- (pos) = rcu_dereference((pos)->next))
-
/*
* Double linked lists with a single pointer list head.
* Mostly useful for hash tables where the two pointer list head is
@@ -726,31 +511,6 @@ static inline void hlist_del(struct hlist_node *n)
n->pprev = LIST_POISON2;
}

-/**
- * hlist_del_rcu - deletes entry from hash list without re-initialization
- * @n: the element to delete from the hash list.
- *
- * Note: list_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_add_head_rcu()
- * or hlist_del_rcu(), running on this same list.
- * However, it is perfectly legal to run concurrently with
- * the _rcu list-traversal primitives, such as
- * hlist_for_each_entry().
- */
-static inline void hlist_del_rcu(struct hlist_node *n)
-{
- __hlist_del(n);
- n->pprev = LIST_POISON2;
-}
-
static inline void hlist_del_init(struct hlist_node *n)
{
if (!hlist_unhashed(n)) {
@@ -759,27 +519,6 @@ static inline void hlist_del_init(struct hlist_node *n)
}
}

-/**
- * hlist_replace_rcu - replace old entry by new one
- * @old : the element to be replaced
- * @new : the new element to insert
- *
- * The @old entry will be replaced with the @new entry atomically.
- */
-static inline void hlist_replace_rcu(struct hlist_node *old,
- struct hlist_node *new)
-{
- struct hlist_node *next = old->next;
-
- new->next = next;
- new->pprev = old->pprev;
- smp_wmb();
- if (next)
- new->next->pprev = &new->next;
- *new->pprev = new;
- old->pprev = LIST_POISON2;
-}
-
static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
{
struct hlist_node *first = h->first;
@@ -790,38 +529,6 @@ static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
n->pprev = &h->first;
}

-
-/**
- * hlist_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,
- * 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_add_head_rcu()
- * or hlist_del_rcu(), running on this same list.
- * However, it is perfectly legal to run concurrently with
- * the _rcu list-traversal primitives, such as
- * hlist_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_add_head_rcu(struct hlist_node *n,
- struct hlist_head *h)
-{
- struct hlist_node *first = h->first;
- n->next = first;
- n->pprev = &h->first;
- smp_wmb();
- if (first)
- first->pprev = &n->next;
- h->first = n;
-}
-
/* next must be != NULL */
static inline void hlist_add_before(struct hlist_node *n,
struct hlist_node *next)
@@ -843,63 +550,6 @@ static inline void hlist_add_after(struct hlist_node *n,
next->next->pprev = &next->next;
}

-/**
- * hlist_add_before_rcu
- * @n: the new element to add to the hash list.
- * @next: the existing element to add the new element before.
- *
- * Description:
- * Adds the specified element to the specified hlist
- * before the specified node 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_add_head_rcu()
- * or hlist_del_rcu(), running on this same list.
- * However, it is perfectly legal to run concurrently with
- * the _rcu list-traversal primitives, such as
- * hlist_for_each_entry_rcu(), used to prevent memory-consistency
- * problems on Alpha CPUs.
- */
-static inline void hlist_add_before_rcu(struct hlist_node *n,
- struct hlist_node *next)
-{
- n->pprev = next->pprev;
- n->next = next;
- smp_wmb();
- next->pprev = &n->next;
- *(n->pprev) = n;
-}
-
-/**
- * hlist_add_after_rcu
- * @prev: the existing element to add the new element after.
- * @n: the new element to add to the hash list.
- *
- * Description:
- * Adds the specified element to the specified hlist
- * after the specified node 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_add_head_rcu()
- * or hlist_del_rcu(), running on this same list.
- * However, it is perfectly legal to run concurrently with
- * the _rcu list-traversal primitives, such as
- * hlist_for_each_entry_rcu(), used to prevent memory-consistency
- * problems on Alpha CPUs.
- */
-static inline void hlist_add_after_rcu(struct hlist_node *prev,
- struct hlist_node *n)
-{
- n->next = prev->next;
- n->pprev = &prev->next;
- smp_wmb();
- prev->next = n;
- if (n->next)
- n->next->pprev = &n->next;
-}
-
#define hlist_entry(ptr, type, member) container_of(ptr,type,member)

#define hlist_for_each(pos, head) \
@@ -960,21 +610,4 @@ static inline void hlist_add_after_rcu(struct hlist_node *prev,
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
pos = n)

-/**
- * hlist_for_each_entry_rcu - iterate over rcu list of given type
- * @tpos: the type * to use as a loop cursor.
- * @pos: the &struct hlist_node to use as a loop cursor.
- * @head: the head for your list.
- * @member: the name of the hlist_node within the struct.
- *
- * This list-traversal primitive may safely run concurrently with
- * the _rcu list-mutation primitives such as hlist_add_head_rcu()
- * as long as the traversal is guarded by rcu_read_lock().
- */
-#define hlist_for_each_entry_rcu(tpos, pos, head, member) \
- for (pos = rcu_dereference((head)->first); \
- pos && ({ prefetch(pos->next); 1;}) && \
- ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
- pos = rcu_dereference(pos->next))
-
#endif
diff --git a/include/linux/rculist.h b/include/linux/rculist.h
new file mode 100644
index 0000000..e673c26
--- /dev/null
+++ b/include/linux/rculist.h
@@ -0,0 +1,375 @@
+#ifndef _LINUX_RCULIST_H
+#define _LINUX_RCULIST_H
+
+/*
+ * RCU-protected list version
+ */
+#include <linux/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.
+ *
+ * In particular, it means that we can not poison the forward
+ * pointers that may still be used for walking the list.
+ *
+ * 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_rcu()
+ * 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);
+ entry->prev = LIST_POISON2;
+}
+
+/**
+ * list_replace_rcu - replace old entry by new one
+ * @old : the element to be replaced
+ * @new : the new element to insert
+ *
+ * The @old entry will be replaced with the @new entry atomically.
+ * Note: @old should not be empty.
+ */
+static inline void list_replace_rcu(struct list_head *old,
+ struct list_head *new)
+{
+ new->next = old->next;
+ new->prev = old->prev;
+ smp_wmb();
+ new->next->prev = new;
+ new->prev->next = new;
+ old->prev = LIST_POISON2;
+}
+
+/**
+ * list_splice_init_rcu - splice an RCU-protected list into an existing list.
+ * @list: the RCU-protected list to splice
+ * @head: the place in the list to splice the first list into
+ * @sync: function to sync: synchronize_rcu(), synchronize_sched(), ...
+ *
+ * @head can be RCU-read traversed concurrently with this function.
+ *
+ * Note that this function blocks.
+ *
+ * Important note: the caller must take whatever action is necessary to
+ * prevent any other updates to @head. In principle, it is possible
+ * to modify the list as soon as sync() begins execution.
+ * If this sort of thing becomes necessary, an alternative version
+ * based on call_rcu() could be created. But only if -really-
+ * needed -- there is no shortage of RCU API members.
+ */
+static inline void list_splice_init_rcu(struct list_head *list,
+ struct list_head *head,
+ void (*sync)(void))
+{
+ struct list_head *first = list->next;
+ struct list_head *last = list->prev;
+ struct list_head *at = head->next;
+
+ if (list_empty(head))
+ return;
+
+ /* "first" and "last" tracking list, so initialize it. */
+
+ INIT_LIST_HEAD(list);
+
+ /*
+ * At this point, the list body still points to the source list.
+ * Wait for any readers to finish using the list before splicing
+ * the list body into the new list. Any new readers will see
+ * an empty list.
+ */
+
+ sync();
+
+ /*
+ * Readers are finished with the source list, so perform splice.
+ * The order is important if the new list is global and accessible
+ * to concurrent RCU readers. Note that RCU readers are not
+ * permitted to traverse the prev pointers without excluding
+ * this function.
+ */
+
+ last->next = at;
+ smp_wmb();
+ head->next = first;
+ first->prev = head;
+ at->prev = last;
+}
+
+/**
+ * list_for_each_rcu - iterate over an rcu-protected list
+ * @pos: the &struct list_head to use as a loop cursor.
+ * @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 rcu list of given type
+ * @pos: the type * to use as a loop cursor.
+ * @head: the head for your list.
+ * @member: the name of the list_struct within the struct.
+ *
+ * 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))
+
+
+/**
+ * list_for_each_continue_rcu
+ * @pos: the &struct list_head to use as a loop cursor.
+ * @head: the head for your list.
+ *
+ * Iterate over an rcu-protected list, continuing after current point.
+ *
+ * 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_continue_rcu(pos, head) \
+ for ((pos) = rcu_dereference((pos)->next); \
+ prefetch((pos)->next), (pos) != (head); \
+ (pos) = rcu_dereference((pos)->next))
+
+/**
+ * hlist_del_rcu - deletes entry from hash list without re-initialization
+ * @n: the element to delete from the hash list.
+ *
+ * Note: list_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_add_head_rcu()
+ * or hlist_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * hlist_for_each_entry().
+ */
+static inline void hlist_del_rcu(struct hlist_node *n)
+{
+ __hlist_del(n);
+ n->pprev = LIST_POISON2;
+}
+
+/**
+ * hlist_replace_rcu - replace old entry by new one
+ * @old : the element to be replaced
+ * @new : the new element to insert
+ *
+ * The @old entry will be replaced with the @new entry atomically.
+ */
+static inline void hlist_replace_rcu(struct hlist_node *old,
+ struct hlist_node *new)
+{
+ struct hlist_node *next = old->next;
+
+ new->next = next;
+ new->pprev = old->pprev;
+ smp_wmb();
+ if (next)
+ new->next->pprev = &new->next;
+ *new->pprev = new;
+ old->pprev = LIST_POISON2;
+}
+
+/**
+ * hlist_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,
+ * 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_add_head_rcu()
+ * or hlist_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * hlist_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_add_head_rcu(struct hlist_node *n,
+ struct hlist_head *h)
+{
+ struct hlist_node *first = h->first;
+ n->next = first;
+ n->pprev = &h->first;
+ smp_wmb();
+ if (first)
+ first->pprev = &n->next;
+ h->first = n;
+}
+
+/**
+ * hlist_add_before_rcu
+ * @n: the new element to add to the hash list.
+ * @next: the existing element to add the new element before.
+ *
+ * Description:
+ * Adds the specified element to the specified hlist
+ * before the specified node 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_add_head_rcu()
+ * or hlist_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * hlist_for_each_entry_rcu(), used to prevent memory-consistency
+ * problems on Alpha CPUs.
+ */
+static inline void hlist_add_before_rcu(struct hlist_node *n,
+ struct hlist_node *next)
+{
+ n->pprev = next->pprev;
+ n->next = next;
+ smp_wmb();
+ next->pprev = &n->next;
+ *(n->pprev) = n;
+}
+
+/**
+ * hlist_add_after_rcu
+ * @prev: the existing element to add the new element after.
+ * @n: the new element to add to the hash list.
+ *
+ * Description:
+ * Adds the specified element to the specified hlist
+ * after the specified node 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_add_head_rcu()
+ * or hlist_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * hlist_for_each_entry_rcu(), used to prevent memory-consistency
+ * problems on Alpha CPUs.
+ */
+static inline void hlist_add_after_rcu(struct hlist_node *prev,
+ struct hlist_node *n)
+{
+ n->next = prev->next;
+ n->pprev = &prev->next;
+ smp_wmb();
+ prev->next = n;
+ if (n->next)
+ n->next->pprev = &n->next;
+}
+
+/**
+ * hlist_for_each_entry_rcu - iterate over rcu list of given type
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
+ * @head: the head for your list.
+ * @member: the name of the hlist_node within the struct.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as hlist_add_head_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define hlist_for_each_entry_rcu(tpos, pos, head, member) \
+ for (pos = rcu_dereference((head)->first); \
+ pos && ({ prefetch(pos->next); 1;}) && \
+ ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
+ pos = rcu_dereference(pos->next))
+
+#endif
diff --git a/kernel/pid.c b/kernel/pid.c
index 34e4e07..484782f 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -30,6 +30,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
+#include <linux/rculist.h>
#include <linux/bootmem.h>
#include <linux/hash.h>
#include <linux/pid_namespace.h>
diff --git a/lib/textsearch.c b/lib/textsearch.c
index be8bda3..a3e500a 100644
--- a/lib/textsearch.c
+++ b/lib/textsearch.c
@@ -97,6 +97,7 @@
#include <linux/types.h>
#include <linux/string.h>
#include <linux/init.h>
+#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/err.h>
#include <linux/textsearch.h>
diff --git a/net/802/psnap.c b/net/802/psnap.c
index ee9e0eb..b3cfe5a 100644
--- a/net/802/psnap.c
+++ b/net/802/psnap.c
@@ -20,6 +20,7 @@
#include <linux/mm.h>
#include <linux/in.h>
#include <linux/init.h>
+#include <linux/rculist.h>

static LIST_HEAD(snap_list);
static DEFINE_SPINLOCK(snap_lock);
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index 2a739ad..e7ddbfa 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -27,6 +27,7 @@
#include <linux/mm.h>
#include <linux/in.h>
#include <linux/init.h>
+#include <linux/rculist.h>
#include <net/p8022.h>
#include <net/arp.h>
#include <linux/rtnetlink.h>
diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 72c5976..142060f 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -15,6 +15,7 @@

#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/rculist.h>
#include <linux/spinlock.h>
#include <linux/times.h>
#include <linux/netdevice.h>
diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c
index e38034a..9e96ffc 100644
--- a/net/bridge/br_stp.c
+++ b/net/bridge/br_stp.c
@@ -13,6 +13,7 @@
* 2 of the License, or (at your option) any later version.
*/v2.6.26-rc2-mm1
#include <linux/kernel.h>
+#include <linux/rculist.h>

#include "br_private.h"
#include "br_private_stp.h"
diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index 02c2f7c..643c032 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -30,8 +30,7 @@
*/

#include <linux/types.h>
-#include <linux/rcupdate.h>
-#include <linux/list.h>
+#include <linux/rculist.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/string.h>
--
1.5.5.GIT

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