spin_trylock
spin_trylock(_l)
spin_trylock(_l); \
#define raw_spin_trylock(rl) spin_trylock(&(rl)->lock)
if (priv->port_up == 0 || !spin_trylock(&ring->comp_lock))
if (!spin_trylock(&ring->comp_lock)) {
if (spin_trylock(&ring->comp_lock)) {