ptrace: introduce ptrace_reparented() helper
Add another trivial helper for the sake of grep. It also auto-documents the
fact that ->parent != real_parent implies ->ptrace.
No functional changes.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/exit.c b/kernel/exit.c
index 879ed6e..0da2921 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -698,7 +698,7 @@
if (unlikely(traced)) {
/* Preserve ptrace links if someone else is tracing this child. */
list_del_init(&p->ptrace_list);
- if (p->parent != p->real_parent)
+ if (ptrace_reparented(p))
list_add(&p->ptrace_list, &p->real_parent->ptrace_children);
} else {
/* If this child is being traced, then we're the one tracing it
@@ -865,8 +865,8 @@
* only has special meaning to our real parent.
*/
if (!task_detached(tsk) && thread_group_empty(tsk)) {
- int signal = (tsk->parent == tsk->real_parent)
- ? tsk->exit_signal : SIGCHLD;
+ int signal = ptrace_reparented(tsk) ?
+ SIGCHLD : tsk->exit_signal;
do_notify_parent(tsk, signal);
} else if (tsk->ptrace) {
do_notify_parent(tsk, SIGCHLD);
@@ -1269,8 +1269,7 @@
return 0;
}
- /* traced means p->ptrace, but not vice versa */
- traced = (p->real_parent != p->parent);
+ traced = ptrace_reparented(p);
if (likely(!traced)) {
struct signal_struct *psig;