Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1#ifndef _LINUX_PID_H
2#define _LINUX_PID_H
3
4enum pid_type
5{
6 PIDTYPE_PID,
7 PIDTYPE_TGID,
8 PIDTYPE_PGID,
9 PIDTYPE_SID,
10 PIDTYPE_MAX
11};
12
13struct 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 */
29extern int FASTCALL(attach_pid(struct task_struct *task, enum pid_type type, int nr));
30
31extern 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 */
37extern struct pid *FASTCALL(find_pid(enum pid_type, int));
38
39extern int alloc_pidmap(void);
40extern void FASTCALL(free_pidmap(int));
41extern 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 */