Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | #ifndef _LINUX_PID_H |
| 2 | #define _LINUX_PID_H |
| 3 | |
| 4 | enum pid_type |
| 5 | { |
| 6 | PIDTYPE_PID, |
| 7 | PIDTYPE_TGID, |
| 8 | PIDTYPE_PGID, |
| 9 | PIDTYPE_SID, |
| 10 | PIDTYPE_MAX |
| 11 | }; |
| 12 | |
| 13 | struct pid |
| 14 | { |
| 15 | /* Try to keep pid_chain in the same cacheline as nr for find_pid */ |
| 16 | int nr; |
| 17 | struct hlist_node pid_chain; |
| 18 | /* list of pids with the same nr, only one of them is in the hash */ |
| 19 | struct list_head pid_list; |
| 20 | }; |
| 21 | |
| 22 | #define pid_task(elem, type) \ |
| 23 | list_entry(elem, struct task_struct, pids[type].pid_list) |
| 24 | |
| 25 | /* |
| 26 | * attach_pid() and detach_pid() must be called with the tasklist_lock |
| 27 | * write-held. |
| 28 | */ |
| 29 | extern int FASTCALL(attach_pid(struct task_struct *task, enum pid_type type, int nr)); |
| 30 | |
| 31 | extern void FASTCALL(detach_pid(struct task_struct *task, enum pid_type)); |
| 32 | |
| 33 | /* |
| 34 | * look up a PID in the hash table. Must be called with the tasklist_lock |
| 35 | * held. |
| 36 | */ |
| 37 | extern struct pid *FASTCALL(find_pid(enum pid_type, int)); |
| 38 | |
| 39 | extern int alloc_pidmap(void); |
| 40 | extern void FASTCALL(free_pidmap(int)); |
| 41 | extern void switch_exec_pids(struct task_struct *leader, struct task_struct *thread); |
| 42 | |
| 43 | #define do_each_task_pid(who, type, task) \ |
| 44 | if ((task = find_task_by_pid_type(type, who))) { \ |
| 45 | prefetch((task)->pids[type].pid_list.next); \ |
| 46 | do { |
| 47 | |
| 48 | #define while_each_task_pid(who, type, task) \ |
| 49 | } while (task = pid_task((task)->pids[type].pid_list.next,\ |
| 50 | type), \ |
| 51 | prefetch((task)->pids[type].pid_list.next), \ |
| 52 | hlist_unhashed(&(task)->pids[type].pid_chain)); \ |
| 53 | } \ |
| 54 | |
| 55 | #endif /* _LINUX_PID_H */ |