task_set_jobctl_pending
task_set_jobctl_pending(child, JOBCTL_TRAP_STOP);
extern bool task_set_jobctl_pending(struct task_struct *task, unsigned long mask);
if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING)) {
if (task_set_jobctl_pending(current, signr | gstop))
task_set_jobctl_pending(t, signr | gstop)) {
task_set_jobctl_pending(current, JOBCTL_TRAP_STOP);
task_set_jobctl_pending(task, mask | JOBCTL_STOP_PENDING);
task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);