ipc: simplify semtimedop/semctl_main() common error path handling
With various straight RCU lock/unlock movements, one common exit path pattern had become rcu_read_unlock(); goto out_wakeup; and in fact there were no cases where we wanted to exit to out_wakeup _without_ releasing the RCU read lock. So replace that pattern with "goto out_rcu_wakeup", and remove the old out_wakeup. Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Родитель
321310ced2
Коммит
c728b9c87b
41
ipc/sem.c
41
ipc/sem.c
|
@ -1077,17 +1077,12 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
|
|||
nsems = sma->sem_nsems;
|
||||
|
||||
err = -EACCES;
|
||||
if (ipcperms(ns, &sma->sem_perm,
|
||||
cmd == SETALL ? S_IWUGO : S_IRUGO)) {
|
||||
rcu_read_unlock();
|
||||
goto out_wakeup;
|
||||
}
|
||||
if (ipcperms(ns, &sma->sem_perm, cmd == SETALL ? S_IWUGO : S_IRUGO))
|
||||
goto out_rcu_wakeup;
|
||||
|
||||
err = security_sem_semctl(sma, cmd);
|
||||
if (err) {
|
||||
rcu_read_unlock();
|
||||
goto out_wakeup;
|
||||
}
|
||||
if (err)
|
||||
goto out_rcu_wakeup;
|
||||
|
||||
err = -EACCES;
|
||||
switch (cmd) {
|
||||
|
@ -1188,10 +1183,8 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
|
|||
/* GETVAL, GETPID, GETNCTN, GETZCNT: fall-through */
|
||||
}
|
||||
err = -EINVAL;
|
||||
if (semnum < 0 || semnum >= nsems) {
|
||||
rcu_read_unlock();
|
||||
goto out_wakeup;
|
||||
}
|
||||
if (semnum < 0 || semnum >= nsems)
|
||||
goto out_rcu_wakeup;
|
||||
|
||||
sem_lock(sma, NULL, -1);
|
||||
curr = &sma->sem_base[semnum];
|
||||
|
@ -1213,8 +1206,8 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
|
|||
|
||||
out_unlock:
|
||||
sem_unlock(sma, -1);
|
||||
out_rcu_wakeup:
|
||||
rcu_read_unlock();
|
||||
out_wakeup:
|
||||
wake_up_sem_queue_do(&tasks);
|
||||
out_free:
|
||||
if(sem_io != fast_sem_io)
|
||||
|
@ -1585,22 +1578,16 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops,
|
|||
}
|
||||
|
||||
error = -EFBIG;
|
||||
if (max >= sma->sem_nsems) {
|
||||
rcu_read_unlock();
|
||||
goto out_wakeup;
|
||||
}
|
||||
if (max >= sma->sem_nsems)
|
||||
goto out_rcu_wakeup;
|
||||
|
||||
error = -EACCES;
|
||||
if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) {
|
||||
rcu_read_unlock();
|
||||
goto out_wakeup;
|
||||
}
|
||||
if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO))
|
||||
goto out_rcu_wakeup;
|
||||
|
||||
error = security_sem_semop(sma, sops, nsops, alter);
|
||||
if (error) {
|
||||
rcu_read_unlock();
|
||||
goto out_wakeup;
|
||||
}
|
||||
if (error)
|
||||
goto out_rcu_wakeup;
|
||||
|
||||
/*
|
||||
* semid identifiers are not unique - find_alloc_undo may have
|
||||
|
@ -1718,8 +1705,8 @@ sleep_again:
|
|||
|
||||
out_unlock_free:
|
||||
sem_unlock(sma, locknum);
|
||||
out_rcu_wakeup:
|
||||
rcu_read_unlock();
|
||||
out_wakeup:
|
||||
wake_up_sem_queue_do(&tasks);
|
||||
out_free:
|
||||
if(sops != fast_sops)
|
||||
|
|
Загрузка…
Ссылка в новой задаче