update name of code to labcodes

labcodes/lab8/kern/mm/swap_fifo.c

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+#include <defs.h>
+#include <x86.h>
+#include <stdio.h>
+#include <string.h>
+#include <swap.h>
+#include <swap_fifo.h>
+#include <list.h>
+
+/* [wikipedia]The simplest Page Replacement Algorithm(PRA) is a FIFO algorithm. The first-in, first-out
+ * page replacement algorithm is a low-overhead algorithm that requires little book-keeping on
+ * the part of the operating system. The idea is obvious from the name - the operating system
+ * keeps track of all the pages in memory in a queue, with the most recent arrival at the back,
+ * and the earliest arrival in front. When a page needs to be replaced, the page at the front
+ * of the queue (the oldest page) is selected. While FIFO is cheap and intuitive, it performs
+ * poorly in practical application. Thus, it is rarely used in its unmodified form. This
+ * algorithm experiences Belady's anomaly.
+ *
+ * Details of FIFO PRA
+ * (1) Prepare: In order to implement FIFO PRA, we should manage all swappable pages, so we can
+ *              link these pages into pra_list_head according the time order. At first you should
+ *              be familiar to the struct list in list.h. struct list is a simple doubly linked list
+ *              implementation. You should know howto USE: list_init, list_add(list_add_after),
+ *              list_add_before, list_del, list_next, list_prev. Another tricky method is to transform
+ *              a general list struct to a special struct (such as struct page). You can find some MACRO:
+ *              le2page (in memlayout.h), (in future labs: le2vma (in vmm.h), le2proc (in proc.h),etc.
+ */
+
+list_entry_t pra_list_head;
+/*
+ * (2) _fifo_init_mm: init pra_list_head and let  mm->sm_priv point to the addr of pra_list_head.
+ *              Now, From the memory control struct mm_struct, we can access FIFO PRA
+ */
+static int
+_fifo_init_mm(struct mm_struct *mm)
+{     
+     list_init(&pra_list_head);
+     mm->sm_priv = &pra_list_head;
+     //cprintf(" mm->sm_priv %x in fifo_init_mm\n",mm->sm_priv);
+     return 0;
+}
+/*
+ * (3)_fifo_map_swappable: According FIFO PRA, we should link the most recent arrival page at the back of pra_list_head qeueue
+ */
+static int
+_fifo_map_swappable(struct mm_struct *mm, uintptr_t addr, struct Page *page, int swap_in)
+{
+    list_entry_t *head=(list_entry_t*) mm->sm_priv;
+    list_entry_t *entry=&(page->pra_page_link);
+ 
+    assert(entry != NULL && head != NULL);
+    //record the page access situlation
+    /*LAB3 EXERCISE 2: YOUR CODE*/ 
+    //(1)link the most recent arrival page at the back of the pra_list_head qeueue.
+    return 0;
+}
+/*
+ *  (4)_fifo_swap_out_victim: According FIFO PRA, we should unlink the  earliest arrival page in front of pra_list_head qeueue,
+ *                            then set the addr of addr of this page to ptr_page.
+ */
+static int
+_fifo_swap_out_victim(struct mm_struct *mm, struct Page ** ptr_page, int in_tick)
+{
+     list_entry_t *head=(list_entry_t*) mm->sm_priv;
+         assert(head != NULL);
+     assert(in_tick==0);
+     /* Select the victim */
+     /*LAB3 EXERCISE 2: YOUR CODE*/ 
+     //(1)  unlink the  earliest arrival page in front of pra_list_head qeueue
+     //(2)  set the addr of addr of this page to ptr_page
+     return 0;
+}
+
+static int
+_fifo_check_swap(void) {
+    cprintf("write Virt Page c in fifo_check_swap\n");
+    *(unsigned char *)0x3000 = 0x0c;
+    assert(pgfault_num==4);
+    cprintf("write Virt Page a in fifo_check_swap\n");
+    *(unsigned char *)0x1000 = 0x0a;
+    assert(pgfault_num==4);
+    cprintf("write Virt Page d in fifo_check_swap\n");
+    *(unsigned char *)0x4000 = 0x0d;
+    assert(pgfault_num==4);
+    cprintf("write Virt Page b in fifo_check_swap\n");
+    *(unsigned char *)0x2000 = 0x0b;
+    assert(pgfault_num==4);
+    cprintf("write Virt Page e in fifo_check_swap\n");
+    *(unsigned char *)0x5000 = 0x0e;
+    assert(pgfault_num==5);
+    cprintf("write Virt Page b in fifo_check_swap\n");
+    *(unsigned char *)0x2000 = 0x0b;
+    assert(pgfault_num==5);
+    cprintf("write Virt Page a in fifo_check_swap\n");
+    *(unsigned char *)0x1000 = 0x0a;
+    assert(pgfault_num==6);
+    cprintf("write Virt Page b in fifo_check_swap\n");
+    *(unsigned char *)0x2000 = 0x0b;
+    assert(pgfault_num==7);
+    cprintf("write Virt Page c in fifo_check_swap\n");
+    *(unsigned char *)0x3000 = 0x0c;
+    assert(pgfault_num==8);
+    cprintf("write Virt Page d in fifo_check_swap\n");
+    *(unsigned char *)0x4000 = 0x0d;
+    assert(pgfault_num==9);
+    return 0;
+}
+
+
+static int
+_fifo_init(void)
+{
+    return 0;
+}
+
+static int
+_fifo_set_unswappable(struct mm_struct *mm, uintptr_t addr)
+{
+    return 0;
+}
+
+static int
+_fifo_tick_event(struct mm_struct *mm)
+{ return 0; }
+
+
+struct swap_manager swap_manager_fifo =
+{
+     .name            = "fifo swap manager",
+     .init            = &_fifo_init,
+     .init_mm         = &_fifo_init_mm,
+     .tick_event      = &_fifo_tick_event,
+     .map_swappable   = &_fifo_map_swappable,
+     .set_unswappable = &_fifo_set_unswappable,
+     .swap_out_victim = &_fifo_swap_out_victim,
+     .check_swap      = &_fifo_check_swap,
+};