dlm: remove usage of list iterator for list_add() after the loop body

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].

Before, the code implicitly used the head when no element was found
when using &pos->list. Since the new variable is only set if an
element was found, the list_add() is performed within the loop
and only done after the loop if it is done on the list head directly.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index f5330e5..20eca22 100644 (file)
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -1321,13 +1321,17 @@ static inline void unhold_lkb(struct dlm_lkb *lkb)
 static void lkb_add_ordered(struct list_head *new, struct list_head *head,
                            int mode)
 {
-       struct dlm_lkb *lkb = NULL;
+       struct dlm_lkb *lkb = NULL, *iter;
 
-       list_for_each_entry(lkb, head, lkb_statequeue)
-               if (lkb->lkb_rqmode < mode)
+       list_for_each_entry(iter, head, lkb_statequeue)
+               if (iter->lkb_rqmode < mode) {
+                       lkb = iter;
+                       list_add_tail(new, &iter->lkb_statequeue);
                        break;
+               }
 
-       __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue);
+       if (!lkb)
+               list_add_tail(new, head);
 }
 
 /* add/remove lkb to rsb's grant/convert/wait queue */