計算機操作系統(tǒng)頁面置換源碼.docxVIP

#include #include#includeusing namespace std;#define MEM_SIZE 32#define RAM_SIZE 16#define SWAP_SIZE 32static char ramRAM_SIZE;static char SwapSWAP_SIZE;map M;struct page_item / 頁表項int ram_addr;int swap_addr;unsigned access;bool present;bool modified;static struct page_item page_tableMEM_SIZE;struct test_itemstruct test_item * next = NULL;int data;static struct test_item * first_list = NULL;static struct test_item * end_list = NULL;test_item head_item;test_item itemRAM_SIZE;/創(chuàng)建鏈表，保存地址的訪問記錄void init_test_list()first_list = &head_item;end_list = &head_item;for (int i = 0; i next = &itemi;itemi.data = i;end_list = &itemi;/ 換頁算法static int algo_swap(void)return first_list-next-data;/ 邏輯地址laddr轉(zhuǎn)換為物理地址paddrstatic int mem_access(int laddr)if (page_tableladdr.present) struct test_item * prev = first_list;struct test_item * cur = first_list-next;while (cur != NULL)if (cur-data = laddr)prev-next = cur-next;cur-next = NULL;end_list-next = cur;end_list = cur;break;prev = cur;cur = cur-next;return page_tableladdr.ram_addr;/ 缺頁處理/ 根據(jù)特定算法選擇被換出的頁int page = algo_swap();struct test_item * prev = first_list;struct test_item * cur = first_list-next;while (cur != NULL)if (cur-data = page)prev-next = cur-next;cur-data = laddr;cur-next = NULL;end_list-next = cur;end_list = cur;break;prev = cur;cur = cur-next;/ 換出if (page_tablepage.modified) / 寫回int data = rampage_tablepage.ram_addr;Swappage_tablepage.swap_addr = data;page_tablepage.present = false;/ 替換int paddr = page_tablepage.ram_addr;page_tableladdr.ram_addr = paddr;rampaddr = Swappage_tableladdr.swap_addr;page_tableladdr.modified = false;page_tableladdr.present = true;page_tableladdr.access = 1;return paddr;int mem_read(int addr, char *buf)if (addr MEM_SIZE)return -1;int paddr = mem_access(addr);*buf = rampaddr;/test_item item;return 0;int mem_write(int addr, char buf)if (addr MEM_SIZE)return -1;int paddr = mem_access(addr);rampaddr = buf;page_tableaddr.modified = true;return 0;void mem_init(void)/ 全部加載到交換空間for (int i = 0; i MEM_SIZE; i+) page_tablei.swap_addr = i;page_tablei.present = false;page_tablei.modified = false;/ 部分加載到內(nèi)存for (int i = 0; i RAM_SIZE; i+) page_tablei.ram_addr = i;page_tablei.present = true;page_tablei.access = 0;void mem_state(void)printf(ram state:t);for (int i = 0; i RAM_SIZE; i+) printf(%d , rami);printf(nswap state:t);for (int i = 0; i next;printf(access record: n );while (cur != NULL)printf(%d , cur-data);prev = cur;cur = cur-next;void mem_test(void)printf(031為地址，在其中依次寫入031，則前16個將會被置換n);int test10 = 1, 3, 5, 9, 6, 7, 19, 18, 31, 0 ;for (int i = 0; i 32; i+)mem_write(i, i);mem_state();history_show();printf(n訪問22號單元，22鏈表末段 n );mem_write(22, 22);history_show();printf(n訪問11單元， 11 鏈表末段，16re