138     idp->top->full = 0; // clear  in __idr_grow()
144     if (new_node != NULL && new_node->full == IDR_FULL)  in __idr_grow()
146         idp->top->full = 1; // 别忘了初始化 full  in __idr_grow()
162     while (NULL == idp->top || idp->top->full == IDR_FULL)  in __idr_get_empty_slot()
175         int pos = __lowbit_id(~cur_layer->full);  in __idr_get_empty_slot()
193             cur_layer->full = 0;  in __idr_get_empty_slot()
225         stk[0]->full |= (1ull << layer_id);  in __idr_mark_full()
235         if (stk[i - 1]->full == IDR_FULL)  in __idr_mark_full()
236             stk[i]->full |= (1ull << layer_id);  in __idr_mark_full()
310     if (mark != 2 && ((stk[0]->full >> layer_id) & 1))  in __idr_erase_full()
311         stk[0]->full ^= (1ull << layer_id);  in __idr_erase_full()
324             if ((stk[layer]->full >> layer_id) & 1)  in __idr_erase_full()
325                 stk[layer]->full ^= (1ull << layer_id);  in __idr_erase_full()
330         else if (stk[layer - 1]->full != IDR_FULL)  in __idr_erase_full()
332             if ((stk[layer]->full >> layer_id) & 1)  in __idr_erase_full()
333                 stk[layer]->full ^= (1ull << layer_id);  in __idr_erase_full()