[PATCH 5/5] ipc/sem: use proper list api for pending_list wakeups

[Davidlohr Bueso]

... saves some LoC and looks cleaner than re-implementing the
calls.

Acked-by: Manfred Spraul <manf...@colorfullife.com>
Signed-off-by: Davidlohr Bueso <dbu...@suse.de>
---
 ipc/sem.c | 38 +++++++++++++-------------------------
 1 file changed, 13 insertions(+), 25 deletions(-)

diff --git a/ipc/sem.c b/ipc/sem.c
index 89adba51e85f..e7da9821bf46 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -812,8 +812,7 @@ static inline int check_restart(struct sem_array *sma, 
struct sem_queue *q)
 static int wake_const_ops(struct sem_array *sma, int semnum,
                          struct wake_q_head *wake_q)
 {
-       struct sem_queue *q;
-       struct list_head *walk;
+       struct sem_queue *q, *tmp;
        struct list_head *pending_list;
        int semop_completed = 0;
 
@@ -822,25 +821,19 @@ static int wake_const_ops(struct sem_array *sma, int 
semnum,
        else
                pending_list = &sma->sem_base[semnum].pending_const;
 
-       walk = pending_list->next;
-       while (walk != pending_list) {
-               int error;
-
-               q = container_of(walk, struct sem_queue, list);
-               walk = walk->next;
-
-               error = perform_atomic_semop(sma, q);
-
-               if (error <= 0) {
-                       /* operation completed, remove from queue & wakeup */
+       list_for_each_entry_safe(q, tmp, pending_list, list) {
+               int error = perform_atomic_semop(sma, q);
 
-                       unlink_queue(sma, q);
+               if (error > 0)
+                       continue;
+               /* operation completed, remove from queue & wakeup */
+               unlink_queue(sma, q);
 
-                       wake_up_sem_queue_prepare(q, error, wake_q);
-                       if (error == 0)
-                               semop_completed = 1;
-               }
+               wake_up_sem_queue_prepare(q, error, wake_q);
+               if (error == 0)
+                       semop_completed = 1;
        }
+
        return semop_completed;
 }
 
@@ -913,8 +906,7 @@ static int do_smart_wakeup_zero(struct sem_array *sma, 
struct sembuf *sops,
  */
 static int update_queue(struct sem_array *sma, int semnum, struct wake_q_head 
*wake_q)
 {
-       struct sem_queue *q;
-       struct list_head *walk;
+       struct sem_queue *q, *tmp;
        struct list_head *pending_list;
        int semop_completed = 0;
 
@@ -924,13 +916,9 @@ static int update_queue(struct sem_array *sma, int semnum, 
struct wake_q_head *w
                pending_list = &sma->sem_base[semnum].pending_alter;
 
 again:
-       walk = pending_list->next;
-       while (walk != pending_list) {
+       list_for_each_entry_safe(q, tmp, pending_list, list) {
                int error, restart;
 
-               q = container_of(walk, struct sem_queue, list);
-               walk = walk->next;
-
                /* If we are scanning the single sop, per-semaphore list of
                 * one semaphore and that semaphore is 0, then it is not
                 * necessary to scan further: simple increments
-- 
2.6.6