Commit 53b6f9fb authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds

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: default avatarOleg Nesterov <oleg@tv-sign.ru>
Acked-by: default avatarRoland McGrath <roland@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2800d8d1
......@@ -98,6 +98,10 @@ extern void ptrace_untrace(struct task_struct *child);
extern int ptrace_may_attach(struct task_struct *task);
extern int __ptrace_may_attach(struct task_struct *task);
static inline int ptrace_reparented(struct task_struct *child)
{
return child->real_parent != child->parent;
}
static inline void ptrace_link(struct task_struct *child,
struct task_struct *new_parent)
{
......
......@@ -698,7 +698,7 @@ reparent_thread(struct task_struct *p, struct task_struct *father, int traced)
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 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
* 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 @@ static int wait_task_zombie(struct task_struct *p, int noreap,
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;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment