WRITE_ENTER
# define WRITE_ENTER(x) ipf_write_enter(x)
# define WRITE_ENTER(x) lock_write((x)->ipf_lk)
# define WRITE_ENTER(x) eMrwlock_write_enter(&(x)->ipf_emu, \
# define WRITE_ENTER(x) ;
# define WRITE_ENTER(x) rw_enter(&(x)->ipf_lk, RW_WRITER)
# define WRITE_ENTER(x) lock_write(&(x)->ipf_lk)
# define WRITE_ENTER(x) MUTEX_ENTER(x)
# define WRITE_ENTER(x) RW_WRLOCK(&(x)->ipf_lk)
# define WRITE_ENTER(x) MUTEX_ENTER(&(x)->ipf_lk)
# define WRITE_ENTER(x) lock_write(&(x)->ipf_lk)
# define WRITE_ENTER(x) mtx_lock(&(x)->ipf_lk)
# define WRITE_ENTER(x) sx_xlock(&(x)->ipf_lk)
#define WRITE_ENTER(x) rw_enter(x, RW_WRITER)
#define WRITE_ENTER(x) rw_enter(x, RW_WRITER)
#define WRITE_ENTER(x) rw_enter(x, RW_WRITER)