include/linux/sem.h

   1 #ifndef _LINUX_SEM_H
   2 #define _LINUX_SEM_H
   3
   4 #include <linux/atomic.h>
   5 #include <linux/rcupdate.h>
   6 #include <linux/cache.h>
   7 #include <uapi/linux/sem.h>
   8
   9 struct task_struct;
  10
  11 /* One sem_array data structure for each set of semaphores in the system. */
  12 struct sem_array {
  13         struct kern_ipc_perm    ____cacheline_aligned_in_smp
  14                                 sem_perm;       /* permissions .. see ipc.h */
  15         time_t                  sem_otime;      /* last semop time */
  16         time_t                  sem_ctime;      /* last change time */
  17         struct sem              *sem_base;      /* ptr to first semaphore in array */
  18         struct list_head        sem_pending;    /* pending operations to be processed */
  19         struct list_head        list_id;        /* undo requests on this array */
  20         int                     sem_nsems;      /* no. of semaphores in array */
  21         int                     complex_count;  /* pending complex operations */
  22 };
  23
  24 #ifdef CONFIG_SYSVIPC
  25
  26 struct sysv_sem {
  27         struct sem_undo_list *undo_list;
  28 };
  29
  30 extern int copy_semundo(unsigned long clone_flags, struct task_struct *tsk);
  31 extern void exit_sem(struct task_struct *tsk);
  32
  33 #else
  34
  35 struct sysv_sem {
  36         /* empty */
  37 };
  38
  39 static inline int copy_semundo(unsigned long clone_flags, struct task_struct *tsk)
  40 {
  41         return 0;
  42 }
  43
  44 static inline void exit_sem(struct task_struct *tsk)
  45 {
  46         return;
  47 }
  48 #endif
  49
  50 #endif /* _LINUX_SEM_H */