SB_DYING
wait_var_event(&sb->s_flags, super_flags(sb, SB_BORN | SB_DYING));
if (super_flags(sb, SB_DYING))
if (sb->s_flags & SB_DYING) {
#define SUPER_WAKE_FLAGS (SB_BORN | SB_DYING | SB_DEAD)
if (!(sb->s_flags & SB_DYING) && sb->s_root &&
super_wake(sb, SB_DYING);
if (super_flags(sb, SB_DYING))
if (super_flags(sb, SB_DYING))