vfork
struct completion *vfork;
vfork = tsk->vfork_done;
if (likely(vfork)) {
complete(vfork);
struct completion *vfork)
killed = wait_for_completion_state(vfork, state);
struct completion vfork;
p->vfork_done = &vfork;
init_completion(&vfork);
if (!wait_for_vfork_done(p, &vfork))
SYSCALL_DEFINE0(vfork)
pid = vfork();
int pid = vfork();
pid_t child = vfork(); \
CASE_TEST(vfork); EXPECT_SYSZR(1, test_fork(FORK_VFORK)); break;
pid = vfork();
pid_t pid = vfork();
pid = vfork();