on_sig_stack      313 arch/x86/kernel/signal_32.c 	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
on_sig_stack     1813 include/linux/sched.h 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
on_sig_stack     2371 kernel/signal.c 		if (on_sig_stack(sp))