From: Davidlohr Bueso <dave@xxxxxxxxxxxx> Subject: ipc/sem: use proper list api for pending_list wakeups ... saves some LoC and looks cleaner than re-implementing the calls. Link: http://lkml.kernel.org/r/1474225896-10066-6-git-send-email-dave@xxxxxxxxxxxx Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx> Acked-by: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- ipc/sem.c | 40 ++++++++++++++-------------------------- 1 file changed, 14 insertions(+), 26 deletions(-) diff -puN ipc/sem.c~ipc-sem-use-proper-list-api-for-pending_list-wakeups ipc/sem.c --- a/ipc/sem.c~ipc-sem-use-proper-list-api-for-pending_list-wakeups +++ a/ipc/sem.c @@ -813,8 +813,7 @@ static inline int check_restart(struct s 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; @@ -823,25 +822,19 @@ static int wake_const_ops(struct sem_arr else pending_list = &sma->sem_base[semnum].pending_const; - walk = pending_list->next; - while (walk != pending_list) { - int error; + list_for_each_entry_safe(q, tmp, pending_list, list) { + int error = perform_atomic_semop(sma, q); - 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 */ - - unlink_queue(sma, q); - - wake_up_sem_queue_prepare(q, error, wake_q); - if (error == 0) - semop_completed = 1; - } + 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; } + return semop_completed; } @@ -914,8 +907,7 @@ static int do_smart_wakeup_zero(struct s */ 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; @@ -925,13 +917,9 @@ static int update_queue(struct sem_array 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 _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
