rcu: split list.h and move rcu-protected lists into rculist.h
Move 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@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Josh Triplett <josh@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
parent
32300751b4
commit
82524746c2
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@ -11,6 +11,7 @@
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#include <linux/irq.h>
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#include <linux/spinlock.h>
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#include <linux/init.h>
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#include <linux/rculist.h>
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#include <asm/sn/addrs.h>
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#include <asm/sn/arch.h>
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#include <asm/sn/intr.h>
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@ -23,6 +23,7 @@
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* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
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*
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*/
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#include <linux/rculist.h>
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#include <linux/kernel.h>
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#include <linux/async_tx.h>
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@ -35,6 +35,7 @@
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#include <rdma/ib_user_verbs.h>
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#include <linux/io.h>
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#include <linux/utsname.h>
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#include <linux/rculist.h>
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#include "ipath_kernel.h"
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#include "ipath_verbs.h"
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@ -31,8 +31,7 @@
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* SOFTWARE.
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*/
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#include <linux/list.h>
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#include <linux/rcupdate.h>
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#include <linux/rculist.h>
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#include "ipath_verbs.h"
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@ -20,7 +20,7 @@
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/list.h>
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#include <linux/rculist.h>
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#include <linux/notifier.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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@ -3,6 +3,7 @@
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#include <asm/atomic.h>
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#include <linux/list.h>
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#include <linux/rculist.h>
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#include <linux/spinlock.h>
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#include <linux/cache.h>
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#include <linux/rcupdate.h>
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@ -84,65 +84,6 @@ static inline void list_add_tail(struct list_head *new, struct list_head *head)
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__list_add(new, head->prev, head);
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}
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/*
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* Insert a new entry between two known consecutive entries.
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*
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* This is only for internal list manipulation where we know
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* the prev/next entries already!
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*/
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static inline void __list_add_rcu(struct list_head * new,
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struct list_head * prev, struct list_head * next)
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{
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new->next = next;
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new->prev = prev;
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smp_wmb();
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next->prev = new;
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prev->next = new;
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}
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/**
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* list_add_rcu - add a new entry to rcu-protected list
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* @new: new entry to be added
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* @head: list head to add it after
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*
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* Insert a new entry after the specified head.
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* This is good for implementing stacks.
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*
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* The caller must take whatever precautions are necessary
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* (such as holding appropriate locks) to avoid racing
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* with another list-mutation primitive, such as list_add_rcu()
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* or list_del_rcu(), running on this same list.
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* However, it is perfectly legal to run concurrently with
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* the _rcu list-traversal primitives, such as
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* list_for_each_entry_rcu().
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*/
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static inline void list_add_rcu(struct list_head *new, struct list_head *head)
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{
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__list_add_rcu(new, head, head->next);
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}
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/**
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* list_add_tail_rcu - add a new entry to rcu-protected list
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* @new: new entry to be added
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* @head: list head to add it before
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*
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* Insert a new entry before the specified head.
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* This is useful for implementing queues.
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*
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* The caller must take whatever precautions are necessary
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* (such as holding appropriate locks) to avoid racing
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* with another list-mutation primitive, such as list_add_tail_rcu()
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* or list_del_rcu(), running on this same list.
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* However, it is perfectly legal to run concurrently with
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* the _rcu list-traversal primitives, such as
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* list_for_each_entry_rcu().
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*/
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static inline void list_add_tail_rcu(struct list_head *new,
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struct list_head *head)
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{
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__list_add_rcu(new, head->prev, head);
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}
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/*
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* Delete a list entry by making the prev/next entries
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* point to each other.
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@ -173,36 +114,6 @@ static inline void list_del(struct list_head *entry)
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extern void list_del(struct list_head *entry);
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#endif
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/**
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* list_del_rcu - deletes entry from list without re-initialization
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* @entry: the element to delete from the list.
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*
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* Note: list_empty() on entry does not return true after this,
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* the entry is in an undefined state. It is useful for RCU based
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* lockfree traversal.
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*
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* In particular, it means that we can not poison the forward
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* pointers that may still be used for walking the list.
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*
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* The caller must take whatever precautions are necessary
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* (such as holding appropriate locks) to avoid racing
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* with another list-mutation primitive, such as list_del_rcu()
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* or list_add_rcu(), running on this same list.
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* However, it is perfectly legal to run concurrently with
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* the _rcu list-traversal primitives, such as
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* list_for_each_entry_rcu().
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*
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* Note that the caller is not permitted to immediately free
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* the newly deleted entry. Instead, either synchronize_rcu()
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* or call_rcu() must be used to defer freeing until an RCU
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* grace period has elapsed.
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*/
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static inline void list_del_rcu(struct list_head *entry)
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{
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__list_del(entry->prev, entry->next);
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entry->prev = LIST_POISON2;
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}
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/**
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* list_replace - replace old entry by new one
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* @old : the element to be replaced
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@ -226,25 +137,6 @@ static inline void list_replace_init(struct list_head *old,
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INIT_LIST_HEAD(old);
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}
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/**
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* list_replace_rcu - replace old entry by new one
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* @old : the element to be replaced
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* @new : the new element to insert
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*
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* The @old entry will be replaced with the @new entry atomically.
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* Note: @old should not be empty.
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*/
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static inline void list_replace_rcu(struct list_head *old,
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struct list_head *new)
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{
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new->next = old->next;
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new->prev = old->prev;
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smp_wmb();
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new->next->prev = new;
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new->prev->next = new;
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old->prev = LIST_POISON2;
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}
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/**
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* list_del_init - deletes entry from list and reinitialize it.
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* @entry: the element to delete from the list.
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}
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}
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/**
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* list_splice_init_rcu - splice an RCU-protected list into an existing list.
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* @list: the RCU-protected list to splice
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* @head: the place in the list to splice the first list into
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* @sync: function to sync: synchronize_rcu(), synchronize_sched(), ...
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*
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* @head can be RCU-read traversed concurrently with this function.
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*
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* Note that this function blocks.
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*
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* Important note: the caller must take whatever action is necessary to
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* prevent any other updates to @head. In principle, it is possible
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* to modify the list as soon as sync() begins execution.
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* If this sort of thing becomes necessary, an alternative version
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* based on call_rcu() could be created. But only if -really-
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* needed -- there is no shortage of RCU API members.
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*/
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static inline void list_splice_init_rcu(struct list_head *list,
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struct list_head *head,
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void (*sync)(void))
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{
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struct list_head *first = list->next;
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struct list_head *last = list->prev;
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struct list_head *at = head->next;
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if (list_empty(head))
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return;
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/* "first" and "last" tracking list, so initialize it. */
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INIT_LIST_HEAD(list);
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/*
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* At this point, the list body still points to the source list.
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* Wait for any readers to finish using the list before splicing
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* the list body into the new list. Any new readers will see
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* an empty list.
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*/
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sync();
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/*
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* Readers are finished with the source list, so perform splice.
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* The order is important if the new list is global and accessible
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* to concurrent RCU readers. Note that RCU readers are not
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* permitted to traverse the prev pointers without excluding
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* this function.
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*/
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last->next = at;
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smp_wmb();
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head->next = first;
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first->prev = head;
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at->prev = last;
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}
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/**
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* list_entry - get the struct for this entry
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* @ptr: the &struct list_head pointer.
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&pos->member != (head); \
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pos = n, n = list_entry(n->member.prev, typeof(*n), member))
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/**
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* list_for_each_rcu - iterate over an rcu-protected list
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* @pos: the &struct list_head to use as a loop cursor.
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* @head: the head for your list.
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*
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* This list-traversal primitive may safely run concurrently with
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* the _rcu list-mutation primitives such as list_add_rcu()
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* as long as the traversal is guarded by rcu_read_lock().
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*/
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#define list_for_each_rcu(pos, head) \
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for (pos = rcu_dereference((head)->next); \
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prefetch(pos->next), pos != (head); \
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pos = rcu_dereference(pos->next))
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#define __list_for_each_rcu(pos, head) \
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for (pos = rcu_dereference((head)->next); \
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pos != (head); \
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pos = rcu_dereference(pos->next))
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/**
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* list_for_each_entry_rcu - iterate over rcu list of given type
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* @pos: the type * to use as a loop cursor.
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* @head: the head for your list.
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* @member: the name of the list_struct within the struct.
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*
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* This list-traversal primitive may safely run concurrently with
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* the _rcu list-mutation primitives such as list_add_rcu()
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* as long as the traversal is guarded by rcu_read_lock().
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*/
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#define list_for_each_entry_rcu(pos, head, member) \
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for (pos = list_entry(rcu_dereference((head)->next), typeof(*pos), member); \
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prefetch(pos->member.next), &pos->member != (head); \
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pos = list_entry(rcu_dereference(pos->member.next), typeof(*pos), member))
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/**
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* list_for_each_continue_rcu
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* @pos: the &struct list_head to use as a loop cursor.
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* @head: the head for your list.
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*
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* Iterate over an rcu-protected list, continuing after current point.
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*
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* This list-traversal primitive may safely run concurrently with
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* the _rcu list-mutation primitives such as list_add_rcu()
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* as long as the traversal is guarded by rcu_read_lock().
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*/
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#define list_for_each_continue_rcu(pos, head) \
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for ((pos) = rcu_dereference((pos)->next); \
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prefetch((pos)->next), (pos) != (head); \
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(pos) = rcu_dereference((pos)->next))
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/*
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* Double linked lists with a single pointer list head.
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* Mostly useful for hash tables where the two pointer list head is
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@ -730,31 +515,6 @@ static inline void hlist_del(struct hlist_node *n)
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n->pprev = LIST_POISON2;
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}
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/**
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* hlist_del_rcu - deletes entry from hash list without re-initialization
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* @n: the element to delete from the hash list.
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*
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* Note: list_unhashed() on entry does not return true after this,
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* the entry is in an undefined state. It is useful for RCU based
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* lockfree traversal.
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*
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* In particular, it means that we can not poison the forward
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* pointers that may still be used for walking the hash list.
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*
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* The caller must take whatever precautions are necessary
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* (such as holding appropriate locks) to avoid racing
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* with another list-mutation primitive, such as hlist_add_head_rcu()
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* or hlist_del_rcu(), running on this same list.
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* However, it is perfectly legal to run concurrently with
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* the _rcu list-traversal primitives, such as
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* hlist_for_each_entry().
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*/
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static inline void hlist_del_rcu(struct hlist_node *n)
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{
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__hlist_del(n);
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n->pprev = LIST_POISON2;
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}
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static inline void hlist_del_init(struct hlist_node *n)
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{
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if (!hlist_unhashed(n)) {
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@ -763,27 +523,6 @@ static inline void hlist_del_init(struct hlist_node *n)
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}
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}
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/**
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* hlist_replace_rcu - replace old entry by new one
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* @old : the element to be replaced
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* @new : the new element to insert
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*
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* The @old entry will be replaced with the @new entry atomically.
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*/
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static inline void hlist_replace_rcu(struct hlist_node *old,
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struct hlist_node *new)
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{
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struct hlist_node *next = old->next;
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new->next = next;
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new->pprev = old->pprev;
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smp_wmb();
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if (next)
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new->next->pprev = &new->next;
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*new->pprev = new;
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old->pprev = LIST_POISON2;
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}
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static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
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{
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struct hlist_node *first = h->first;
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@ -794,38 +533,6 @@ static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
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n->pprev = &h->first;
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}
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/**
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* hlist_add_head_rcu
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* @n: the element to add to the hash list.
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* @h: the list to add to.
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*
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* Description:
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* Adds the specified element to the specified hlist,
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* while permitting racing traversals.
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*
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* The caller must take whatever precautions are necessary
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* (such as holding appropriate locks) to avoid racing
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* with another list-mutation primitive, such as hlist_add_head_rcu()
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* or hlist_del_rcu(), running on this same list.
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* However, it is perfectly legal to run concurrently with
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* the _rcu list-traversal primitives, such as
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* hlist_for_each_entry_rcu(), used to prevent memory-consistency
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* problems on Alpha CPUs. Regardless of the type of CPU, the
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* list-traversal primitive must be guarded by rcu_read_lock().
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*/
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static inline void hlist_add_head_rcu(struct hlist_node *n,
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struct hlist_head *h)
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{
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struct hlist_node *first = h->first;
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n->next = first;
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n->pprev = &h->first;
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smp_wmb();
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if (first)
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first->pprev = &n->next;
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h->first = n;
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}
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/* next must be != NULL */
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static inline void hlist_add_before(struct hlist_node *n,
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struct hlist_node *next)
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@ -847,63 +554,6 @@ static inline void hlist_add_after(struct hlist_node *n,
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next->next->pprev = &next->next;
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}
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/**
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* hlist_add_before_rcu
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* @n: the new element to add to the hash list.
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* @next: the existing element to add the new element before.
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*
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* Description:
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* Adds the specified element to the specified hlist
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* before the specified node while permitting racing traversals.
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*
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* The caller must take whatever precautions are necessary
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* (such as holding appropriate locks) to avoid racing
|
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* with another list-mutation primitive, such as hlist_add_head_rcu()
|
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* or hlist_del_rcu(), running on this same list.
|
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* However, it is perfectly legal to run concurrently with
|
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* the _rcu list-traversal primitives, such as
|
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* hlist_for_each_entry_rcu(), used to prevent memory-consistency
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* problems on Alpha CPUs.
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*/
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static inline void hlist_add_before_rcu(struct hlist_node *n,
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struct hlist_node *next)
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{
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n->pprev = next->pprev;
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n->next = next;
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smp_wmb();
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next->pprev = &n->next;
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*(n->pprev) = n;
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}
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/**
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* hlist_add_after_rcu
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* @prev: the existing element to add the new element after.
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* @n: the new element to add to the hash list.
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*
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* Description:
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* Adds the specified element to the specified hlist
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* after the specified node while permitting racing traversals.
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*
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* 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) \
|
||||
|
@ -964,21 +614,4 @@ 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
|
||||
|
|
|
@ -0,0 +1,396 @@
|
|||
#ifndef _LINUX_RCULIST_H
|
||||
#define _LINUX_RCULIST_H
|
||||
|
||||
#ifdef __KERNEL__
|
||||
|
||||
/*
|
||||
* 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 = (head)->next; \
|
||||
prefetch(rcu_dereference(pos)->next), pos != (head); \
|
||||
pos = pos->next)
|
||||
|
||||
#define __list_for_each_rcu(pos, head) \
|
||||
for (pos = (head)->next; \
|
||||
rcu_dereference(pos) != (head); \
|
||||
pos = pos->next)
|
||||
|
||||
/**
|
||||
* list_for_each_safe_rcu
|
||||
* @pos: the &struct list_head to use as a loop cursor.
|
||||
* @n: another &struct list_head to use as temporary storage
|
||||
* @head: the head for your list.
|
||||
*
|
||||
* Iterate over an rcu-protected list, safe against removal of list entry.
|
||||
*
|
||||
* 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_safe_rcu(pos, n, head) \
|
||||
for (pos = (head)->next; \
|
||||
n = rcu_dereference(pos)->next, pos != (head); \
|
||||
pos = n)
|
||||
|
||||
/**
|
||||
* 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((head)->next, typeof(*pos), member); \
|
||||
prefetch(rcu_dereference(pos)->member.next), \
|
||||
&pos->member != (head); \
|
||||
pos = list_entry(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) = (pos)->next; \
|
||||
prefetch(rcu_dereference((pos))->next), (pos) != (head); \
|
||||
(pos) = (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 = (head)->first; \
|
||||
rcu_dereference(pos) && ({ prefetch(pos->next); 1; }) && \
|
||||
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); \
|
||||
pos = pos->next)
|
||||
|
||||
#endif /* __KERNEL__ */
|
||||
#endif
|
|
@ -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>
|
||||
|
|
|
@ -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>
|
||||
|
|
|
@ -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);
|
||||
|
|
|
@ -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>
|
||||
|
|
|
@ -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>
|
||||
|
|
|
@ -13,6 +13,7 @@
|
|||
* 2 of the License, or (at your option) any later version.
|
||||
*/
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/rculist.h>
|
||||
|
||||
#include "br_private.h"
|
||||
#include "br_private_stp.h"
|
||||
|
|
|
@ -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>
|
||||
|
|
Loading…
Reference in New Issue