From d198cd6d6d02d0a335af2deacb60816ebb4719d1 Mon Sep 17 00:00:00 2001 From: Manfred Spraul Date: Fri, 6 Jun 2014 14:37:49 -0700 Subject: [PATCH] ipc/sem.c: change perform_atomic_semop parameters Right now, perform_atomic_semop gets the content of sem_queue as individual fields. Changes that, instead pass a pointer to sem_queue. This is a preparation for the next patch: it uses sem_queue to store the reason why a task must sleep. Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Cc: Michael Kerrisk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/sem.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/ipc/sem.c b/ipc/sem.c index d73b3ef..b93b561 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -585,21 +585,23 @@ SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) /** * perform_atomic_semop - Perform (if possible) a semaphore operation * @sma: semaphore array - * @sops: array with operations that should be checked - * @nsops: number of operations - * @un: undo array - * @pid: pid that did the change + * @q: struct sem_queue that describes the operation * * Returns 0 if the operation was possible. * Returns 1 if the operation is impossible, the caller must sleep. * Negative values are error codes. */ -static int perform_atomic_semop(struct sem_array *sma, struct sembuf *sops, - int nsops, struct sem_undo *un, int pid) +static int perform_atomic_semop(struct sem_array *sma, struct sem_queue *q) { - int result, sem_op; + int result, sem_op, nsops, pid; struct sembuf *sop; struct sem *curr; + struct sembuf *sops; + struct sem_undo *un; + + sops = q->sops; + nsops = q->nsops; + un = q->undo; for (sop = sops; sop < sops + nsops; sop++) { curr = sma->sem_base + sop->sem_num; @@ -627,6 +629,7 @@ static int perform_atomic_semop(struct sem_array *sma, struct sembuf *sops, } sop--; + pid = q->pid; while (sop >= sops) { sma->sem_base[sop->sem_num].sempid = pid; sop--; @@ -779,8 +782,7 @@ static int wake_const_ops(struct sem_array *sma, int semnum, q = container_of(walk, struct sem_queue, list); walk = walk->next; - error = perform_atomic_semop(sma, q->sops, q->nsops, - q->undo, q->pid); + error = perform_atomic_semop(sma, q); if (error <= 0) { /* operation completed, remove from queue & wakeup */ @@ -892,8 +894,7 @@ again: if (semnum != -1 && sma->sem_base[semnum].semval == 0) break; - error = perform_atomic_semop(sma, q->sops, q->nsops, - q->undo, q->pid); + error = perform_atomic_semop(sma, q); /* Does q->sleeper still need to sleep? */ if (error > 0) @@ -1871,8 +1872,13 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, if (un && un->semid == -1) goto out_unlock_free; - error = perform_atomic_semop(sma, sops, nsops, un, - task_tgid_vnr(current)); + queue.sops = sops; + queue.nsops = nsops; + queue.undo = un; + queue.pid = task_tgid_vnr(current); + queue.alter = alter; + + error = perform_atomic_semop(sma, &queue); if (error == 0) { /* If the operation was successful, then do * the required updates. @@ -1889,12 +1895,6 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * task into the pending queue and go to sleep. */ - queue.sops = sops; - queue.nsops = nsops; - queue.undo = un; - queue.pid = task_tgid_vnr(current); - queue.alter = alter; - if (nsops == 1) { struct sem *curr; curr = &sma->sem_base[sops->sem_num]; -- 2.7.4