diff options
Diffstat (limited to 'ipc')
| -rw-r--r-- | ipc/mqueue.c | 4 | ||||
| -rw-r--r-- | ipc/sem.c | 56 |
2 files changed, 57 insertions, 3 deletions
diff --git a/ipc/mqueue.c b/ipc/mqueue.c index ed049ea568f..2e0ecfcc881 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -449,8 +449,8 @@ static int wq_sleep(struct mqueue_inode_info *info, int sr, set_current_state(TASK_INTERRUPTIBLE); spin_unlock(&info->lock); - time = schedule_hrtimeout_range_clock(timeout, - HRTIMER_MODE_ABS, 0, CLOCK_REALTIME); + time = schedule_hrtimeout_range_clock(timeout, 0, + HRTIMER_MODE_ABS, CLOCK_REALTIME); while (ewp->state == STATE_PENDING) cpu_relax(); diff --git a/ipc/sem.c b/ipc/sem.c index c8e00f8b4be..5215a81420d 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -90,6 +90,52 @@ #include <asm/uaccess.h> #include "util.h" +/* One semaphore structure for each semaphore in the system. */ +struct sem { + int semval; /* current value */ + int sempid; /* pid of last operation */ + struct list_head sem_pending; /* pending single-sop operations */ +}; + +/* One queue for each sleeping process in the system. */ +struct sem_queue { + struct list_head simple_list; /* queue of pending operations */ + struct list_head list; /* queue of pending operations */ + struct task_struct *sleeper; /* this process */ + struct sem_undo *undo; /* undo structure */ + int pid; /* process id of requesting process */ + int status; /* completion status of operation */ + struct sembuf *sops; /* array of pending operations */ + int nsops; /* number of operations */ + int alter; /* does *sops alter the array? */ +}; + +/* Each task has a list of undo requests. They are executed automatically + * when the process exits. + */ +struct sem_undo { + struct list_head list_proc; /* per-process list: * + * all undos from one process + * rcu protected */ + struct rcu_head rcu; /* rcu struct for sem_undo */ + struct sem_undo_list *ulp; /* back ptr to sem_undo_list */ + struct list_head list_id; /* per semaphore array list: + * all undos for one array */ + int semid; /* semaphore set identifier */ + short *semadj; /* array of adjustments */ + /* one per semaphore */ +}; + +/* sem_undo_list controls shared access to the list of sem_undo structures + * that may be shared among all a CLONE_SYSVSEM task group. + */ +struct sem_undo_list { + atomic_t refcnt; + spinlock_t lock; + struct list_head list_proc; +}; + + #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) #define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) @@ -1426,6 +1472,8 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, queue.status = -EINTR; queue.sleeper = current; + +sleep_again: current->state = TASK_INTERRUPTIBLE; sem_unlock(sma); @@ -1460,7 +1508,6 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * Array removed? If yes, leave without sem_unlock(). */ if (IS_ERR(sma)) { - error = -EIDRM; goto out_free; } @@ -1479,6 +1526,13 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, */ if (timeout && jiffies_left == 0) error = -EAGAIN; + + /* + * If the wakeup was spurious, just retry + */ + if (error == -EINTR && !signal_pending(current)) + goto sleep_again; + unlink_queue(sma, &queue); out_unlock_free: |