introduce the walk_process_tree() helper

Add the new helper to walk the process tree, the next patch adds a user.
Note that it visits the group leaders only, proc_visitor can do
for_each_thread itself or we can trivially extend walk_process_tree() to
do this.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This commit is contained in:
Oleg Nesterov
2017-01-30 18:06:11 +03:00
committed by Eric W. Biederman
parent 015bb305b8
commit 0f1b92cbdd
2 changed files with 35 additions and 0 deletions

View File

@@ -3053,6 +3053,9 @@ extern bool current_is_single_threaded(void);
#define for_each_process_thread(p, t) \
for_each_process(p) for_each_thread(p, t)
typedef int (*proc_visitor)(struct task_struct *p, void *data);
void walk_process_tree(struct task_struct *top, proc_visitor, void *);
static inline int get_nr_threads(struct task_struct *tsk)
{
return tsk->signal->nr_threads;