diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-04 14:04:29 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-04 20:21:58 -0400 |
commit | c728b9c87b59fb943c4cba0552d38152787a4ab6 (patch) | |
tree | 072a4bac6686701ef46eca2fabb06306c400391b /ipc/sem.c | |
parent | 321310ced2d6cc0175c76fa512fa8a829ee35223 (diff) |
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>
Diffstat (limited to 'ipc/sem.c')
-rw-r--r-- | ipc/sem.c | 41 |
1 files changed, 14 insertions, 27 deletions
@@ -1077,17 +1077,12 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, | |||
1077 | nsems = sma->sem_nsems; | 1077 | nsems = sma->sem_nsems; |
1078 | 1078 | ||
1079 | err = -EACCES; | 1079 | err = -EACCES; |
1080 | if (ipcperms(ns, &sma->sem_perm, | 1080 | if (ipcperms(ns, &sma->sem_perm, cmd == SETALL ? S_IWUGO : S_IRUGO)) |
1081 | cmd == SETALL ? S_IWUGO : S_IRUGO)) { | 1081 | goto out_rcu_wakeup; |
1082 | rcu_read_unlock(); | ||
1083 | goto out_wakeup; | ||
1084 | } | ||
1085 | 1082 | ||
1086 | err = security_sem_semctl(sma, cmd); | 1083 | err = security_sem_semctl(sma, cmd); |
1087 | if (err) { | 1084 | if (err) |
1088 | rcu_read_unlock(); | 1085 | goto out_rcu_wakeup; |
1089 | goto out_wakeup; | ||
1090 | } | ||
1091 | 1086 | ||
1092 | err = -EACCES; | 1087 | err = -EACCES; |
1093 | switch (cmd) { | 1088 | switch (cmd) { |
@@ -1188,10 +1183,8 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, | |||
1188 | /* GETVAL, GETPID, GETNCTN, GETZCNT: fall-through */ | 1183 | /* GETVAL, GETPID, GETNCTN, GETZCNT: fall-through */ |
1189 | } | 1184 | } |
1190 | err = -EINVAL; | 1185 | err = -EINVAL; |
1191 | if (semnum < 0 || semnum >= nsems) { | 1186 | if (semnum < 0 || semnum >= nsems) |
1192 | rcu_read_unlock(); | 1187 | goto out_rcu_wakeup; |
1193 | goto out_wakeup; | ||
1194 | } | ||
1195 | 1188 | ||
1196 | sem_lock(sma, NULL, -1); | 1189 | sem_lock(sma, NULL, -1); |
1197 | curr = &sma->sem_base[semnum]; | 1190 | curr = &sma->sem_base[semnum]; |
@@ -1213,8 +1206,8 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, | |||
1213 | 1206 | ||
1214 | out_unlock: | 1207 | out_unlock: |
1215 | sem_unlock(sma, -1); | 1208 | sem_unlock(sma, -1); |
1209 | out_rcu_wakeup: | ||
1216 | rcu_read_unlock(); | 1210 | rcu_read_unlock(); |
1217 | out_wakeup: | ||
1218 | wake_up_sem_queue_do(&tasks); | 1211 | wake_up_sem_queue_do(&tasks); |
1219 | out_free: | 1212 | out_free: |
1220 | if(sem_io != fast_sem_io) | 1213 | if(sem_io != fast_sem_io) |
@@ -1585,22 +1578,16 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, | |||
1585 | } | 1578 | } |
1586 | 1579 | ||
1587 | error = -EFBIG; | 1580 | error = -EFBIG; |
1588 | if (max >= sma->sem_nsems) { | 1581 | if (max >= sma->sem_nsems) |
1589 | rcu_read_unlock(); | 1582 | goto out_rcu_wakeup; |
1590 | goto out_wakeup; | ||
1591 | } | ||
1592 | 1583 | ||
1593 | error = -EACCES; | 1584 | error = -EACCES; |
1594 | if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) { | 1585 | if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) |
1595 | rcu_read_unlock(); | 1586 | goto out_rcu_wakeup; |
1596 | goto out_wakeup; | ||
1597 | } | ||
1598 | 1587 | ||
1599 | error = security_sem_semop(sma, sops, nsops, alter); | 1588 | error = security_sem_semop(sma, sops, nsops, alter); |
1600 | if (error) { | 1589 | if (error) |
1601 | rcu_read_unlock(); | 1590 | goto out_rcu_wakeup; |
1602 | goto out_wakeup; | ||
1603 | } | ||
1604 | 1591 | ||
1605 | /* | 1592 | /* |
1606 | * semid identifiers are not unique - find_alloc_undo may have | 1593 | * semid identifiers are not unique - find_alloc_undo may have |
@@ -1718,8 +1705,8 @@ sleep_again: | |||
1718 | 1705 | ||
1719 | out_unlock_free: | 1706 | out_unlock_free: |
1720 | sem_unlock(sma, locknum); | 1707 | sem_unlock(sma, locknum); |
1708 | out_rcu_wakeup: | ||
1721 | rcu_read_unlock(); | 1709 | rcu_read_unlock(); |
1722 | out_wakeup: | ||
1723 | wake_up_sem_queue_do(&tasks); | 1710 | wake_up_sem_queue_do(&tasks); |
1724 | out_free: | 1711 | out_free: |
1725 | if(sops != fast_sops) | 1712 | if(sops != fast_sops) |