ww_class
extern struct ww_class reservation_ww_class;
struct ww_class *ww_class;
struct ww_class classname = { \
struct ww_class *ww_class);
extern void ww_mutex_init(struct ww_mutex *ww, struct ww_class *ww_class);
ctx->ww_class->name, 0);
ww_acquire_init(struct ww_acquire_ctx *ctx, struct ww_class *ww_class)
ctx->stamp = atomic_fetchadd_long(&ww_class->stamp, 1);
ctx->ww_class = ww_class;
ww_mutex_init(struct ww_mutex *ww, struct ww_class *ww_class)
lockinit(&ww->base, ww_class->name, 0, LK_CANRECURSE);