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 <manfred@colorfullife.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Manfred Spraul 2014-06-06 14:37:49 -07:00 committed by Linus Torvalds
parent 2f2ed41dca
commit d198cd6d6d

View File

@ -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 @@ static int update_queue(struct sem_array *sma, int semnum, struct list_head *pt)
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];