![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/10\/20261003234107-6ac192936433a.png\")
<\/p>\n\u672c\u6587\u6863\u662f\u72ec\u7acb\u5b9e\u73b0\u5185\u6838，\u5e76\u4e14\u8bb0\u5f55\u5185\u6838\u5b66\u4e60\u8fc7\u7a0b，\u4ee5\u5e2e\u52a9\u540e\u6765\u7684\u5b66\u4e60\u8005\u6765\u7406\u89e3\u548c\u5b9e\u73b0\u5185\u6838，\u5982\u679c\u6709\u8bb2\u89e3\u4e0d\u6e05\u695a\u7684\u5730\u65b9\u8bf7\u89c1\u8c05\u3002<\/p>\n
#ifndef PROCESS_DEFS_H
\n#define PROCESS_DEFS_H<\/p>\n
\/\/ \u524d\u7f6e\u58f0\u660e
\nstruct task_struct;
\nstruct exec_domain;<\/p>\n
\/\/ \u5b8c\u6574\u5b9a\u4e49 restart_block
\nstruct restart_block {
\n long fn;
\n unsigned long arg0, arg1, arg2, arg3;
\n};<\/p>\n
typedef unsigned int __u32;
\ntypedef unsigned long mm_segment_t;<\/p>\n
struct thread_info {
\n struct task_struct *task;
\n struct exec_domain *exec_domain;
\n __u32 flags;
\n __u32 status;
\n __u32 cpu;
\n int preempt_count;
\n mm_segment_t addr_limit;
\n struct restart_block restart_block;
\n void *sysenter_return;
\n int uaccess_err;
\n};<\/p>\n
#endif \/\/ PROCESS_DEFS_H<\/p>\n
\u4f5c\u7528：\u9632\u6b62\u540c\u4e00\u4e2a\u5934\u6587\u4ef6\u88ab\u591a\u6b21 include，\u9020\u6210\u91cd\u590d\u5b9a\u4e49\u7f16\u8bd1\u9519\u8bef\u3002<\/p>\n
\u4f5c\u7528：\u53ef\u4ee5\u6682\u65f6\u4e0d\u9700\u8981\u5199\u51fa\u8fdb\u7a0b\u63cf\u8ff0\u7b26\u5185\u90e8\u6210\u5458\u3002<\/p>\n
\u4f5c\u7528：\u7ed9\u5df2\u6709\u7684\u6570\u636e\u7c7b\u578b\u8d77\u522b\u540d，\u4e0d\u662f\u521b\u5efa\u65b0\u7c7b\u578b\u3002<\/p>\n
struct restart_block {
\n long fn; \/\/ long，8\u5b57\u8282 \u2192 dq
\n unsigned long arg0; \/\/ unsigned long，8\u5b57\u8282 \u2192 dq
\n unsigned long arg1; \/\/ unsigned long，8\u5b57\u8282 \u2192 dq
\n unsigned long arg2; \/\/ unsigned long，8\u5b57\u8282 \u2192 dq
\n unsigned long arg3; \/\/ unsigned long，8\u5b57\u8282 \u2192 dq
\n};<\/p>\n
NASM：<\/p>\n
; struct restart_block
\nRB_FN dq 0
\nRB_ARG0 dq 0
\nRB_ARG1 dq 0
\nRB_ARG2 dq 0
\nRB_ARG3 dq 0<\/p>\n
struct thread_info {
\n struct task_struct *task; \/\/ 64\u4f4d\u6307\u9488，8B \u2192 dq
\n struct exec_domain *exec_domain; \/\/ 64\u4f4d\u6307\u9488，8B \u2192 dq
\n __u32 flags; \/\/ __u32，4B \u2192 dd
\n __u32 status; \/\/ __u32，4B \u2192 dd
\n __u32 cpu; \/\/ __u32，4B \u2192 dd
\n int preempt_count; \/\/ int，4B \u2192 dd
\n mm_segment_t addr_limit; \/\/ unsigned long，8B \u2192 dq
\n struct restart_block restart_block; \/\/ \u5185\u5d4c\u7ed3\u6784\u4f53，40B（5\u4e2adq）
\n void *sysenter_return; \/\/ 64\u4f4d\u6307\u9488，8B \u2192 dq
\n int uaccess_err; \/\/ int，4B \u2192 dd
\n};<\/p>\n
NASM \u9759\u6001\u5b9a\u4e49（.data \u6bb5，db\/dw\/dd\/dq）<\/p>\n
section .data
\nti:
\nti_task dq 0 ; struct task_struct *task; 8B
\nti_exec_domain dq 0 ; struct exec_domain *exec_domain; 8B
\nti_flags dd 0 ; __u32 flags; 4B
\nti_status dd 0 ; __u32 status;4B
\nti_cpu dd 0 ; __u32 cpu;4B
\nti_preempt_cnt dd 0 ; int preempt_count;4B
\nti_addr_limit dq 0 ; mm_segment_t addr_limit;8B<\/p>\n
; struct restart_block \u5185\u5d4c\u5b9e\u4f53（40\u5b57\u8282）
\nti_rb_fn dq 0
\nti_rb_arg0 dq 0
\nti_rb_arg1 dq 0
\nti_rb_arg2 dq 0
\nti_rb_arg3 dq 0<\/p>\n
ti_sysenter_ret dq 0 ; void *sysenter_return;8B
\nti_uaccess_err dd 0 ; int uaccess_err;4B<\/p>\n
\u8fdb\u7a0b\u72b6\u6001\u662f\u653e\u5728 task_struct（\u8fdb\u7a0b\u63cf\u8ff0\u7b26）\u91cc\u9762\u7684\u6210\u5458\u3002<\/p>\n
\/\/ \u7c7b\u578b\u522b\u540d（\u548cNASM\u4fdd\u6301\u4e00\u81f4，\u4e0d\u4f9d\u8d56\u5185\u6838\u5934）
\ntypedef unsigned int __u32;
\ntypedef unsigned long mm_segment_t;<\/p>\n
\/\/ ===================== 1. \u8fdb\u7a0b\u72b6\u6001\u5e38\u91cf（\u72b6\u6001\u5f00\u5173）=====================
\n#define TASK_RUNNING 0 \/\/ \u5c31\u7eea\/\u6b63\u5728\u8fd0\u884c，\u8c03\u5ea6\u5668\u53ef\u4ee5\u8c03\u5ea6\u4e0aCPU
\n#define TASK_INTERRUPTIBLE 1 \/\/ \u53ef\u4e2d\u65ad\u7761\u7720，\u7b49\u5f85\u4e8b\u4ef6，\u6536\u5230\u4fe1\u53f7\u53ef\u5524\u9192
\n#define TASK_UNINTERRUPTIBLE 2 \/\/ \u4e0d\u53ef\u4e2d\u65ad\u7761\u7720，\u7b49\u5f85IO，\u4e0d\u54cd\u5e94\u4fe1\u53f7
\n#define TASK_STOPPED 4 \/\/ \u8fdb\u7a0b\u6682\u505c
\n#define TASK_ZOMBIE 8 \/\/ \u50f5\u5c38\u8fdb\u7a0b，\u5df2\u9000\u51fa，\u7b49\u5f85\u7236\u8fdb\u7a0b\u56de\u6536<\/p>\n
\/\/ ===================== 2. restart_block \u7ed3\u6784\u4f53（\u5185\u5d4c\u5728thread_info）=====================
\nstruct restart_block {
\n long fn; \/\/ \u91cd\u542f\u51fd\u6570\u6307\u9488
\n unsigned long arg0, arg1, arg2, arg3; \/\/ \u51fd\u6570\u53c2\u6570
\n};<\/p>\n
\/\/ ===================== 3. \u8fdb\u7a0b\u63cf\u8ff0\u7b26 task_struct（\u4fdd\u5b58\u8fdb\u7a0b\u6838\u5fc3\u4fe1\u606f，\u542bstate\u72b6\u6001）=====================
\nstruct task_struct {
\n long pid; \/\/ \u8fdb\u7a0bID
\n long state; \/\/ \u2705\u8fdb\u7a0b\u72b6\u6001\u5f00\u5173（\u6838\u5fc3）
\n char comm[16]; \/\/ \u8fdb\u7a0b\u540d\u79f0，16\u5b57\u8282\u5b57\u7b26\u4e32
\n};<\/p>\n
\/\/ ===================== 4. thread_info \u7ebf\u7a0b\u4fe1\u606f\u7ed3\u6784\u4f53 =====================
\nstruct thread_info {
\n struct task_struct *task; \/\/ \u6307\u5411\u8fdb\u7a0b\u63cf\u8ff0\u7b26task_struct
\n struct exec_domain *exec_domain; \/\/ \u6267\u884c\u57df\u6307\u9488
\n __u32 flags;
\n __u32 status;
\n __u32 cpu;
\n int preempt_count;
\n mm_segment_t addr_limit;
\n struct restart_block restart_block; \/\/ \u5185\u5d4crestart_block\u5b9e\u4f53
\n void *sysenter_return;
\n int uaccess_err;
\n};<\/p>\n
1\u3001struct restart_block<\/p>\n
struct restart_block {
\n long fn; \/\/ long 8B \u2192 dq
\n unsigned long arg0; \/\/ 8B \u2192 dq
\n unsigned long arg1; \/\/ 8B \u2192 dq
\n unsigned long arg2; \/\/ 8B \u2192 dq
\n unsigned long arg3; \/\/ 8B \u2192 dq
\n};<\/p>\n
2\u3001struct task_struct（\u8fdb\u7a0b\u63cf\u8ff0\u7b26，\u65b0\u589e state）<\/p>\n
struct task_struct {
\n long pid; \/\/ 8B \u2192 dq
\n long state; \/\/ 8B \u2192 dq \u2705\u8fdb\u7a0b\u72b6\u6001
\n char comm[16]; \/\/ 16B \u2192 db 16（\u8fde\u7eed16\u4e2a\u5b57\u8282）
\n};<\/p>\n
3\u3001struct thread_info<\/p>\n
struct thread_info {
\n struct task_struct *task; \/\/ \u6307\u94888B \u2192 dq
\n struct exec_domain *exec_domain; \/\/ \u6307\u94888B \u2192 dq
\n __u32 flags; \/\/ 4B \u2192 dd
\n __u32 status; \/\/ 4B \u2192 dd
\n __u32 cpu; \/\/ 4B \u2192 dd
\n int preempt_count; \/\/ int 4B \u2192 dd
\n mm_segment_t addr_limit; \/\/ unsigned long 8B \u2192 dq
\n struct restart_block restart_block; \/\/ \u5185\u5d4c40\u5b57\u8282
\n void *sysenter_return; \/\/ \u6307\u94888B \u2192 dq
\n int uaccess_err; \/\/ int 4B \u2192 dd
\n};<\/p>\n
; ========== restart_block \u504f\u79fb ==========
\nRB_FN equ 0
\nRB_ARG0 equ 8
\nRB_ARG1 equ 16
\nRB_ARG2 equ 24
\nRB_ARG3 equ 32<\/p>\n
; ========== thread_info \u504f\u79fb ==========
\nTI_TASK equ 0
\nTI_EXEC_DOMAIN equ 8
\nTI_FLAGS equ 16
\nTI_STATUS equ 20
\nTI_CPU equ 24
\nTI_PREEMPT_CNT equ 28
\nTI_ADDR_LIMIT equ 32
\nTI_RESTART_BLOCK equ 40
\nTI_SYSENTER_RET equ 80
\nTI_UACCESS_ERR equ 88<\/p>\n
; ==========\u3010\u65b0\u589e\u3011task_struct \u8fdb\u7a0b\u63cf\u8ff0\u7b26\u504f\u79fb ==========
\nTASK_PID equ 0
\nTASK_STATE equ 8 ; \u8fdb\u7a0b\u72b6\u6001state\u504f\u79fb
\nTASK_COMM equ 16<\/p>\n
EQU \u5c31\u662f\u7ed9\u6570\u5b57\u8d77\u522b\u540d，\u65b9\u4fbf\u9605\u8bfb\u8bb0\u5fc6；\u66f4\u5927\u4ef7\u503c\u662f\u7edf\u4e00\u7ba1\u7406\u5e38\u91cf，\u4fee\u6539\u53ea\u6539\u4e00\u5904，\u907f\u514d\u786c\u7f16\u7801\u6570\u5b57\u5e26\u6765\u7684\u9519\u4f4d bug\u3002<\/p>\n
; test.asm
\n; NASM 64\u4f4d Linux \u7b80\u6613\u8fdb\u7a0b\u72b6\u6001\u8c03\u5ea6\u6f14\u793a
\n; \u7f16\u8bd1：nasm -f elf64 test.asm -o test.o && ld test.o -o test
\n; \u8fd0\u884c：.\/test<\/p>\n
; ====================== \u5168\u90e8EQU\u5e38\u91cf\u3010\u653e\u5728\u6587\u4ef6\u6700\u5f00\u5934\u3011======================
\n; ——– \u8fdb\u7a0b\u72b6\u6001\u5e38\u91cf ——–
\nTASK_RUNNING equ 0
\nTASK_INTERRUPTIBLE equ 1
\nTASK_UNINTERRUPTIBLE equ 2
\nTASK_STOPPED equ 4
\nTASK_ZOMBIE equ 8<\/p>\n
; ——– restart_block \u6210\u5458\u504f\u79fb ——–
\nRB_FN equ 0
\nRB_ARG0 equ 8
\nRB_ARG1 equ 16
\nRB_ARG2 equ 24
\nRB_ARG3 equ 32<\/p>\n
; ——– thread_info \u6210\u5458\u504f\u79fb ——–
\nTI_TASK equ 0
\nTI_EXEC_DOMAIN equ 8
\nTI_FLAGS equ 16
\nTI_STATUS equ 20
\nTI_CPU equ 24
\nTI_PREEMPT_CNT equ 28
\nTI_ADDR_LIMIT equ 32
\nTI_RESTART_BLOCK equ 40
\nTI_SYSENTER_RET equ 80
\nTI_UACCESS_ERR equ 88
\nTI_SIZE equ 92 ; thread_info\u603b\u5b57\u8282<\/p>\n
; ——– task_struct \u8fdb\u7a0b\u63cf\u8ff0\u7b26\u504f\u79fb ——–
\nTASK_PID equ 0
\nTASK_STATE equ 8
\nTASK_COMM equ 16
\nTASK_SIZE equ 32
\n; ========================================================================<\/p>\n
section .bss
\n ; task_struct \u6574\u5757\u9884\u7559，\u8d77\u59cb\u6807\u7b7e task1
\ntask1 resb TASK_SIZE<\/p>\n
; thread_info \u6574\u5757\u9884\u7559，\u8d77\u59cb\u6807\u7b7e ti1 \u3010\u4fee\u590d\u5173\u952e\u70b9！\u3011
\nti1 resb TI_SIZE<\/p>\n
section .data
\n msg_run db "\u8fdb\u7a0b：\u53ef\u8fd0\u884c\u72b6\u6001，\u51c6\u5907\u8c03\u5ea6",10,0
\n msg_sleep db "\u8fdb\u7a0b：\u7761\u7720\u72b6\u6001，\u8df3\u8fc7\u8c03\u5ea6",10,0<\/p>\n
section .text
\nglobal _start<\/p>\n
_start:
\n ; \u521d\u59cb\u5316：ti1.task = &task1 （\u5173\u8054thread_info \u548c\u8fdb\u7a0b\u63cf\u8ff0\u7b26）
\n mov rdi, ti1
\n mov qword [rdi + TI_TASK], task1<\/p>\n
; \u8bbe\u7f6ePID=1001
\n mov rbx, [rdi + TI_TASK]
\n mov qword [rbx + TASK_PID], 1001<\/p>\n
; \u8bbe\u7f6e\u8fdb\u7a0b\u72b6\u6001：TASK_INTERRUPTIBLE（\u7761\u7720\u6001）
\n mov qword [rbx + TASK_STATE], TASK_INTERRUPTIBLE<\/p>\n
; ========== \u8c03\u5ea6\u5224\u65ad：\u8df3\u8f6c\u903b\u8f91 ==========
\n mov rax, [rbx + TASK_STATE]
\n cmp rax, TASK_RUNNING ; \u5224\u65adstate\u662f\u5426\u7b49\u4e8e\u8fd0\u884c\u6001
\n je SCHED_RUN ; \u76f8\u7b49\u5219\u8df3\u8f6c\u5230SCHED_RUN
\n jmp SCHED_SKIP ; \u5426\u5219\u8df3\u5230\u8df3\u8fc7\u8c03\u5ea6<\/p>\n
SCHED_RUN:
\n mov rsi, msg_run
\n call print_str
\n jmp EXIT_PROG<\/p>\n
SCHED_SKIP:
\n mov rsi, msg_sleep
\n call print_str<\/p>\n
EXIT_PROG:
\n ; \u7cfb\u7edf\u8c03\u7528\u9000\u51fa\u7a0b\u5e8f
\n mov rax,60
\n mov rdi,0
\n syscall<\/p>\n
; \u5b50\u51fd\u6570 print_str(rsi=\u5b57\u7b26\u4e32\u9996\u5730\u5740)
\nprint_str:
\n push rsi
\n xor rdx,rdx
\n.count:
\n cmp byte [rsi+rdx],0
\n je .out
\n inc rdx
\n jmp .count
\n.out:
\n mov rax,1
\n mov rdi,1
\n syscall
\n pop rsi
\n ret<\/p>\n
; boot.asm \u4e3b\u5f15\u5bfc\u6247\u533a 512\u5b57\u8282
\n[bits 16]
\n[org 0x7c00]<\/p>\n
start:
\n mov ax, 0
\n mov es, ax
\n mov bx, 0x1000 ; \u628a\u7b2c\u4e8c\u9636\u6bb5\u52a0\u8f7d\u5230\u7269\u7406\u5730\u57400x1000
\n mov ah, 0x02 ; BIOS\u8bfb\u6247\u533a
\n mov al, 1 ; \u8bfb\u53d61\u4e2a\u6247\u533a(512\u5b57\u8282)
\n mov ch, 0 ; \u78c1\u90530
\n mov cl, 2 ; \u4ece\u7b2c2\u6247\u533a\u8bfb\u53d6（\u6247\u533a1\u662f\u5f53\u524d\u5f15\u5bfc\u6247\u533a）
\n mov dh, 0 ; \u78c1\u59340
\n int 0x13
\n jc disk_error ; \u8bfb\u76d8\u5931\u8d25\u8df3\u8f6c<\/p>\n
cli
\n lgdt [gdt_desc]<\/p>\n
mov eax, cr0
\n or eax, 1
\n mov cr0, eax<\/p>\n
jmp 0x08:pm_entry ; \u8fdc\u8df3\u8f6c，\u5237\u65b0CS\u8fdb\u5165\u4fdd\u62a4\u6a21\u5f0f<\/p>\n
[bits 32]
\npm_entry:
\n mov ax, 0x10
\n mov ds, ax
\n mov es, ax
\n mov ss, ax
\n mov esp, 0x7c00<\/p>\n
; \u6e05\u7a7a\u9875\u76ee\u5f55 0x2000
\n mov edi, 0x2000
\n mov ecx, 1024
\n xor eax, eax
\n rep stosd<\/p>\n
; \u9875\u76ee\u5f55\u7b2c0\u9879：\u6307\u5411\u9875\u88680x3000，Present+RW
\n mov dword [0x2000], 0x3003 <\/p>\n
; \u6e05\u7a7a\u9875\u8868 0x3000
\n mov edi, 0x3000
\n mov ecx, 1024
\n xor eax, eax
\n rep stosd<\/p>\n
; \u586b\u5145\u9875\u8868：\u6620\u5c04\u865a\u62df\u5730\u57400~4MB \u5230\u7269\u7406\u5730\u57400~4MB
\n mov ebx, 0x3000
\n mov eax, 0x00000003
\n mov ecx, 1024
\nfill_pt:
\n mov [ebx], eax
\n add ebx, 4
\n add eax, 0x1000
\n loop fill_pt<\/p>\n
mov eax, 0x2000
\n mov cr3, eax ; CR3 = \u9875\u76ee\u5f55\u7269\u7406\u5730\u5740<\/p>\n
mov eax, cr0
\n or eax, 0x80000000
\n mov cr0, eax ; \u5f00\u542f\u5206\u9875<\/p>\n
jmp 0x08:0x1000 ; \u8df3\u5230\u7b2c\u4e8c\u9636\u6bb5\u5185\u6838\u4ee3\u7801！<\/p>\n
disk_error:
\n cli
\n hlt<\/p>\n
gdt_start:
\n dq 0
\ngdt_code:
\n dw 0xffff
\n dw 0
\n db 0
\n db 0x9a
\n db 0xcf
\n db 0
\ngdt_data:
\n dw 0xffff
\n dw 0
\n db 0
\n db 0x92
\n db 0xcf
\n db 0
\ngdt_end:<\/p>\n
gdt_desc:
\n dw gdt_end – gdt_start – 1
\n dd gdt_start<\/p>\n
times 510 – ($-$$) db 0
\ndw 0xaa55<\/p>\n
; kernel.asm \u7b2c\u4e8c\u9636\u6bb5\u88f8\u673a\u5185\u6838，\u52a0\u8f7d\u52300x1000
\n[bits 32]<\/p>\n
; ===================== EQU\u5e38\u91cf \u5bf9\u5e94C\u7ed3\u6784\u4f53 =====================
\n; \u8fdb\u7a0b\u72b6\u6001
\nTASK_RUNNING equ 0
\nTASK_INTERRUPTIBLE equ 1
\nTASK_UNINTERRUPTIBLE equ 2
\nTASK_STOPPED equ 4
\nTASK_ZOMBIE equ 8<\/p>\n
; restart_block
\nRB_FN equ 0
\nRB_ARG0 equ 4
\nRB_ARG1 equ 8
\nRB_ARG2 equ 12
\nRB_ARG3 equ 16<\/p>\n
; thread_info
\nTI_TASK equ 0
\nTI_EXEC_DOMAIN equ 4
\nTI_FLAGS equ 8
\nTI_STATUS equ 12
\nTI_CPU equ 16
\nTI_PREEMPT_CNT equ 20
\nTI_ADDR_LIMIT equ 24
\nTI_RESTART_BLOCK equ 28
\nTI_SYSENTER_RET equ 48
\nTI_UACCESS_ERR equ 52
\nTI_SIZE equ 56<\/p>\n
; task_struct \u8fdb\u7a0b\u63cf\u8ff0\u7b26
\nTASK_PID equ 0
\nTASK_STATE equ 4
\nTASK_COMM equ 8
\nTASK_SIZE equ 24<\/p>\n
; \u663e\u5b58\u6587\u672c\u6a21\u5f0f 0xB8000，\u6bcf\u4e2a\u5b57\u7b26 2\u5b57\u8282：ASCII + \u989c\u8272
\nVID_MEM equ 0xB8000
\n; \u989c\u8272：0x0F = \u9ed1\u5e95\u767d\u5b57
\nWHITE_ON_BLACK equ 0x0F
\n; \u989c\u8272：0x0A = \u9ed1\u5e95\u7eff\u5b57
\nGREEN_ON_BLACK equ 0x0A
\n; \u989c\u8272：0x04 = \u9ed1\u5e95\u7ea2\u5b57
\nRED_ON_BLACK equ 0x04<\/p>\n
; ============= \u5168\u5c40\u6570\u636e：\u4e24\u4e2a\u8fdb\u7a0b\u7684thread_info\u3001task_struct ===========
\n; \u653e\u5728\u9759\u6001\u5185\u5b58，\u88f8\u673a\u76f4\u63a5\u56fa\u5b9a\u5730\u5740
\n; task1 PCB
\ntask1 equ 0x1200
\nti1 equ 0x1300<\/p>\n
; task2 PCB
\ntask2 equ 0x1400
\nti2 equ 0x1500<\/p>\n
KERNEL_START:
\n ; ======== \u521d\u59cb\u5316\u8fdb\u7a0b1 =========
\n mov dword [ti1 + TI_TASK], task1 ; ti1->task = &task1
\n mov dword [task1 + TASK_PID], 1
\n mov dword [task1 + TASK_STATE], TASK_RUNNING
\n mov byte [task1 + TASK_COMM], 'p'
\n mov byte [task1 + TASK_COMM+1], '1'<\/p>\n
; ======== \u521d\u59cb\u5316\u8fdb\u7a0b2 =========
\n mov dword [ti2 + TI_TASK], task2
\n mov dword [task2 + TASK_PID], 2
\n mov dword [task2 + TASK_STATE], TASK_INTERRUPTIBLE
\n mov byte [task2 + TASK_COMM], 'p'
\n mov byte [task2 + TASK_COMM+1], '2'<\/p>\n
; \u6e05\u5c4f
\n call clear_screen<\/p>\n
; ========== \u7b80\u6613\u8c03\u5ea6\u5faa\u73af ==========
\nSCHED_LOOP:
\n ; \u68c0\u67e5\u8fdb\u7a0b1
\n mov esi, ti1
\n call check_process<\/p>\n
; \u68c0\u67e5\u8fdb\u7a0b2
\n mov esi, ti2
\n call check_process<\/p>\n
; \u7b80\u5355\u5ef6\u65f6\u5faa\u73af
\n mov ecx,0x080000
\ndelay:
\n loop delay
\n jmp SCHED_LOOP<\/p>\n
; \u51fd\u6570 check_process(esi = thread_info\u6307\u9488)
\n; \u8bfb\u53d6task->state，\u5224\u65ad\u72b6\u6001，\u8f93\u51fa\u5f69\u8272\u6587\u5b57\u5230\u663e\u5b58
\ncheck_process:
\n push ebx
\n push eax
\n push edx<\/p>\n
mov ebx, [esi + TI_TASK] ; ebx = ti->task (task_struct)
\n mov eax, [ebx + TASK_STATE] ; eax = task->state
\n mov edx, [ebx + TASK_PID] ; edx = pid<\/p>\n
; \u663e\u5b58\u4f4d\u7f6e：pid*80*2，\u6bcf\u884c80\u5b57\u7b26，2\u5b57\u8282\u4e00\u4e2a\u5b57\u7b26
\n mov edi, VID_MEM
\n imul edx, 160
\n add edi, edx<\/p>\n
cmp eax, TASK_RUNNING
\n je .proc_run
\n cmp eax, TASK_INTERRUPTIBLE
\n je .proc_sleep
\n jmp .proc_other<\/p>\n
.proc_run:
\n ; \u7eff\u5b57：\u8fd0\u884c\u6001
\n mov byte [edi], 'P'
\n mov byte [edi+1], GREEN_ON_BLACK
\n mov byte [edi+2], 'I'
\n mov byte [edi+3], GREEN_ON_BLACK
\n mov byte [edi+4], 'D'
\n mov byte [edi+5], GREEN_ON_BLACK
\n mov byte [edi+6], ':'
\n mov byte [edi+7], GREEN_ON_BLACK
\n add edi,8
\n mov al, [ebx + TASK_COMM]
\n mov [edi],al
\n mov byte [edi+1],GREEN_ON_BLACK
\n mov al, [ebx + TASK_COMM+1]
\n mov [edi+2],al
\n mov byte [edi+3],GREEN_ON_BLACK
\n mov byte [edi+4], ' '
\n mov byte [edi+5],GREEN_ON_BLACK
\n mov byte [edi+6],'R'
\n mov byte [edi+7],GREEN_ON_BLACK
\n mov byte [edi+8],'U'
\n mov byte [edi+9],GREEN_ON_BLACK
\n mov byte [edi+10],'N'
\n mov byte [edi+11],GREEN_ON_BLACK
\n jmp .proc_done
\n.proc_sleep:
\n ; \u7ea2\u5b57：\u7761\u7720\u6001
\n mov byte [edi], 'P'
\n mov byte [edi+1], RED_ON_BLACK
\n mov byte [edi+2], 'I'
\n mov byte [edi+3], RED_ON_BLACK
\n mov byte [edi+4], 'D'
\n mov byte [edi+5], RED_ON_BLACK
\n mov byte [edi+6], ':'
\n mov byte [edi+7], RED_ON_BLACK
\n add edi,8
\n mov al, [ebx + TASK_COMM]
\n mov [edi],al
\n mov byte [edi+1],RED_ON_BLACK
\n mov al, [ebx + TASK_COMM+1]
\n mov [edi+2],al
\n mov byte [edi+3],RED_ON_BLACK
\n mov byte [edi+4], ' '
\n mov byte [edi+5],RED_ON_BLACK
\n mov byte [edi+6],'S'
\n mov byte [edi+7],RED_ON_BLACK
\n mov byte [edi+8],'L'
\n mov byte [edi+9],RED_ON_BLACK
\n mov byte [edi+10],'E'
\n mov byte [edi+11],RED_ON_BLACK
\n.proc_other:
\n.proc_done:
\n pop edx
\n pop eax
\n pop ebx
\n ret<\/p>\n
; \u6e05\u5c4f：\u628a\u6574\u4e2a\u5c4f\u5e55\u586b\u5145\u9ed1\u5e95\u7a7a\u767d
\nclear_screen:
\n mov edi, VID_MEM
\n mov ecx, 80*25
\n mov ah, WHITE_ON_BLACK
\n mov al, ' '
\n.cls_loop:
\n mov [edi], ax
\n add edi, 2
\n loop .cls_loop
\n ret<\/p>\n
; \u8865\u9f50\u5230512\u5b57\u8282\u6247\u533a
\ntimes 512 – ($ – KERNEL_START) db 0<\/p>\n
# \u7f16\u8bd1\u5f15\u5bfc\u6247\u533a
\nnasm -f bin boot.asm -o boot.bin
\n# \u7f16\u8bd1\u7b2c\u4e8c\u9636\u6bb5\u5185\u6838
\nnasm -f bin kernel.asm -o kernel.bin<\/p>\n
# \u751f\u6210\u8f6f\u76d8\u955c\u50cf，1\u4e2a\u6247\u533aboot + 1\u6247\u533akernel，\u5176\u4f59\u586b\u51450
\ndd if=\/dev\/zero of=os.img bs=512 count=2880
\ndd if=boot.bin of=os.img conv=notrunc
\ndd if=kernel.bin of=os.img bs=512 seek=1 conv=notrunc<\/p>\n
qemu-system-i386 -drive format=raw,file=os.img<\/p>\n
<\/p>\n
\u4e00\u4e2a\u7528 NASM + C \u5199\u7684 32 \u4f4d\u88f8\u673a\u5185\u6838：\u4ece\u8f6f\u76d8\u955c\u50cf\u542f\u52a8，\u8fdb\u5165\u4fdd\u62a4\u6a21\u5f0f\u3001\u5efa\u7acb\u81ea\u5df1\u7684 GDT \u548c\u5206\u9875，\u7136\u540e\u8fd0\u884c\u4e24\u4e2a\u8fdb\u7a0b（proc1 \/ proc2），\u7528\u534f\u4f5c\u5f0f\u4e0a\u4e0b\u6587\u5207\u6362\u8f6e\u6d41\u6267\u884c，\u5e76\u5728 VGA \u6587\u672c\u6a21\u5f0f\u4e0b\u6253\u5370\u5e26\u6709\u81ea\u589e\u8ba1\u6570\u7684\u8fd0\u884c\u4fe1\u606f\u3002<\/p>\n
1\u3001\u8fd0\u884c\u73af\u5883<\/p>\n
\u00a0\u00a0\u00a0\u00a064 \u4f4d Linux（Debian \/ Ubuntu \/ Kali \u7b49），\u6216 Windows \u4e0a\u7684 WSL2\u3002\u7ec8\u7aef\u91cc\u80fd\u6267\u884c make\u3002<\/p>\n
2\u3001\u4f9d\u8d56\u5de5\u5177<\/p>\n
\u00a0\u00a0\u00a0\u00a0nasm \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u6c47\u7f16\u5668，\u6c47\u7f16 boot.asm\u3001loader.asm
\n\u00a0 \u00a0 gcc\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0C \u7f16\u8bd1\u5668，\u9700\u8981\u652f\u6301 -m32 \u7f16\u8bd1（\u80fd\u751f\u6210 32 \u4f4d\u76ee\u6807\u6587\u4ef6\u5373\u53ef）
\n\u00a0 \u00a0 ld (binutils)\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u94fe\u63a5\u5668，\u7528 -m elf_i386 \u6309 kernel.ld \u94fe\u63a5
\n\u00a0 \u00a0 make\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u6784\u5efa\u5de5\u5177，\u6267\u884c Makefile
\n\u00a0 \u00a0 qemu-system-i386 \u00a0 \u00a0\u6a21\u62df\u5668，\u8fd0\u884c\u751f\u6210\u7684 os.img<\/p>\n
3\u3001\u5b89\u88c5\u547d\u4ee4（Debian \/ Ubuntu \/ Kali）<\/p>\n
\u00a0\u00a0\u00a0\u00a0sudo apt-get update
\n\u00a0 \u00a0 sudo apt-get install -y nasm gcc make binutils qemu-system-x86<\/p>\n
\u00a0 \u00a0 # \u53ef\u9009：\u60f3\u5728\u7cfb\u7edf\u91cc\u53e6\u5916\u94fe\u63a5\u666e\u901a 32 \u4f4d\u7a0b\u5e8f\u65f6\u518d\u88c5
\n\u00a0 \u00a0 sudo apt-get install -y gcc-multilib<\/p>\n
\u00a0 \u00a0 \u8bf4\u660e：\u672c\u9879\u76ee\u662f freestanding \u94fe\u63a5（\u4e0d\u8fde libc\u3001\u76f4\u63a5\u7528 ld），\u6240\u4ee5\u4e0d\u88c5
\n\u00a0 \u00a0 gcc-multilib \u4e5f\u80fd\u6784\u5efa\u6210\u529f，\u5b83\u53ea\u662f\u65b9\u4fbf\u4f60\u505a\u522b\u7684 32 \u4f4d\u5b9e\u9a8c\u3002<\/p>\n
\u00a0 \u00a0 make\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u751f\u6210 os.img
\n\u00a0 \u00a0 make run\u00a0 \u00a0 \u00a0 \u00a0 \u00a0\u7528 QEMU \u542f\u52a8\u5e76\u663e\u793a\u5185\u6838\u753b\u9762
\n\u00a0 \u00a0 make debug \u00a0 \u00a0\u542f\u52a8 QEMU \u5e76\u505c\u5728\u8d77\u70b9\u7b49\u5f85 gdb（gdb: target remote :1234）
\n\u00a0 \u00a0 make clean \u00a0 \u00a0\u00a0\u5220\u9664\u5168\u90e8\u7f16\u8bd1\u4ea7\u7269
\n\u00a0 \u00a0 make rebuild\u00a0 \u00a0\u5148 clean \u518d\u91cd\u65b0\u7f16\u8bd1<\/p>\n
\u00a0 \u00a0\u6ca1\u6709\u56fe\u5f62\u754c\u9762\u65f6，\u53ef\u7528\u65e0\u754c\u9762\u65b9\u5f0f\u542f\u52a8：<\/p>\n
\u00a0 \u00a0 qemu-system-i386 -drive format=raw,file=os.img -display none<\/p>\n
boot.asm<\/p>\n
\u4e3b\u5f15\u5bfc\u6247\u533a（512 \u5b57\u8282）\u3002\u7528 INT 13h \u8bfb 16 \u4e2a\u6247\u533a\u5230 0x1000；\u8bbe\u7f6e GDT；
\n\u5efa\u7acb 0x10000 \u9875\u76ee\u5f55 + 0x11000 \u9875\u8868（\u6052\u7b49\u6620\u5c04 0~4MB）；
\n\u5f00\u542f\u5206\u9875\u540e\u8df3\u5230 0x1000<\/p>\n
; boot.asm \u4e3b\u5f15\u5bfc\u6247\u533a 512\u5b57\u8282
\n[bits 16]
\n[org 0x7c00]<\/p>\n
start:
\n mov ax, 0
\n mov es, ax
\n mov bx, 0x1000 ; \u628a\u7b2c\u4e8c\u9636\u6bb5\u52a0\u8f7d\u5230\u7269\u7406\u5730\u57400x1000
\n mov ah, 0x02 ; BIOS\u8bfb\u6247\u533a
\n mov al, 16 ; \u8bfb\u53d616\u4e2a\u6247\u533a(8KB)，\u8db3\u591f\u88c5\u4e0b\u6574\u4e2a\u5185\u6838\u955c\u50cf
\n mov ch, 0 ; \u78c1\u90530
\n mov cl, 2 ; \u4ece\u7b2c2\u6247\u533a\u8bfb\u53d6（\u6247\u533a1\u662f\u5f53\u524d\u5f15\u5bfc\u6247\u533a）
\n mov dh, 0 ; \u78c1\u59340
\n int 0x13
\n jc disk_error ; \u8bfb\u76d8\u5931\u8d25\u8df3\u8f6c<\/p>\n
cli
\n lgdt [gdt_desc]<\/p>\n
mov eax, cr0
\n or eax, 1
\n mov cr0, eax<\/p>\n
jmp 0x08:pm_entry ; \u8fdc\u8df3\u8f6c，\u5237\u65b0CS\u8fdb\u5165\u4fdd\u62a4\u6a21\u5f0f<\/p>\n
[bits 32]
\npm_entry:
\n mov ax, 0x10
\n mov ds, ax
\n mov es, ax
\n mov ss, ax
\n mov esp, 0x7c00<\/p>\n
; \u6e05\u7a7a\u9875\u76ee\u5f55 0x10000
\n mov edi, 0x10000
\n mov ecx, 1024
\n xor eax, eax
\n rep stosd<\/p>\n
; \u9875\u76ee\u5f55\u7b2c0\u9879：\u6307\u5411\u9875\u88680x11000，Present+RW
\n mov dword [0x10000], 0x11003<\/p>\n
; \u6e05\u7a7a\u9875\u8868 0x11000
\n mov edi, 0x11000
\n mov ecx, 1024
\n xor eax, eax
\n rep stosd<\/p>\n
; \u586b\u5145\u9875\u8868：\u6620\u5c04\u865a\u62df\u5730\u57400~4MB \u5230\u7269\u7406\u5730\u57400~4MB
\n mov ebx, 0x11000
\n mov eax, 0x00000003
\n mov ecx, 1024
\nfill_pt:
\n mov [ebx], eax
\n add ebx, 4
\n add eax, 0x1000
\n loop fill_pt<\/p>\n
mov eax, 0x10000
\n mov cr3, eax ; CR3 = \u9875\u76ee\u5f55\u7269\u7406\u5730\u5740<\/p>\n
mov eax, cr0
\n or eax, 0x80000000
\n mov cr0, eax ; \u5f00\u542f\u5206\u9875<\/p>\n
jmp 0x08:0x1000 ; \u8df3\u5230\u7b2c\u4e8c\u9636\u6bb5\u5185\u6838\u4ee3\u7801！<\/p>\n
disk_error:
\n cli
\n hlt<\/p>\n
gdt_start:
\n dq 0
\ngdt_code:
\n dw 0xffff
\n dw 0
\n db 0
\n db 0x9a
\n db 0xcf
\n db 0
\ngdt_data:
\n dw 0xffff
\n dw 0
\n db 0
\n db 0x92
\n db 0xcf
\n db 0
\ngdt_end:<\/p>\n
gdt_desc:
\n dw gdt_end – gdt_start – 1
\n dd gdt_start<\/p>\n
times 510 – ($-$$) db 0
\ndw 0xaa55<\/p>\n
loader.asm<\/p>\n
\u4fdd\u62a4\u6a21\u5f0f\u4e0b\u7684\u5165\u53e3 start\u3002\u628a\u6808\u8bbe\u4e3a 0x6000 \u5e76\u8c03\u7528 C \u7684 kernel_main；
\n\u8fd4\u56de\u540e\u6b7b\u5faa\u73af\u505c\u673a\u3002<\/p>\n
; loader.asm [bits 32]
\n[bits 32]
\nglobal start
\nextern kernel_main <\/p>\n
section .text
\nstart:
\n ; \u8bbe\u7f6eC\u4ee3\u7801\u6808
\n mov esp, 0x6000
\n call kernel_main<\/p>\n
; \u6b7b\u5faa\u73af，\u5185\u6838\u8fd4\u56de\u5c31\u505c\u673a
\nhang_loop:
\n hlt
\n jmp hang_loop<\/p>\n
kernel.c<\/p>\n
\u5185\u6838\u4e3b\u4f53：\u8fdb\u7a0b\u63cf\u8ff0\u7b26 task_struct\u3001\u4e0a\u4e0b\u6587\u5207\u6362 cpu_switch \/ switch_to\u3001
\n\u4e24\u4e2a\u8fdb\u7a0b proc1 \/ proc2\u3001\u663e\u5b58\u8f93\u51fa\u4e0e\u6574\u6570\u663e\u793a\u3002<\/p>\n
\/\/ kernel.c
\n\/\/ 32 \u4f4d\u88f8\u673a C \u5185\u6838（freestanding，\u6ca1\u6709 libc）
\n\/\/ \u76ee\u6807：\u8ba9\u4e24\u4e2a\u8fdb\u7a0b proc1 \/ proc2 \u901a\u8fc7 switch_to \u505a\u4e0a\u4e0b\u6587\u5207\u6362，\u8f6e\u6d41\u8fd0\u884c\u3002
\n\/\/
\n\/\/ \u7269\u7406\u5185\u5b58\u5e03\u5c40（boot.asm \u5df2\u5efa\u7acb 0~4MB \u7684\u6052\u7b49\u5206\u9875）：
\n\/\/ 0x00001000 \u5185\u6838\u955c\u50cf (.text\/.rodata\/.data\/.bss)
\n\/\/ 0x00003000 proc1 \u5185\u6838\u6808（\u6808\u9876 0x4000，\u5411\u4e0b\u589e\u957f）
\n\/\/ 0x00004000 proc2 \u5185\u6838\u6808（\u6808\u9876 0x5000，\u5411\u4e0b\u589e\u957f）
\n\/\/ 0x00005000 \u5185\u6838\u4e3b\u7ebf\u7a0b\u6808（\u6808\u9876 0x6000，\u5411\u4e0b\u589e\u957f）
\n\/\/ 0x00010000 \u9875\u76ee\u5f55 PD（boot.asm \u7528，\u5185\u6838\u4e0d\u78b0）
\n\/\/ 0x00011000 \u9875\u8868 PT（boot.asm \u7528，\u5185\u6838\u4e0d\u78b0）<\/p>\n
#define TASK_RUNNING 0
\n#define TASK_INTERRUPTIBLE 1
\n#define TASK_UNINTERRUPTIBLE 2
\n#define TASK_STOPPED 4
\n#define TASK_ZOMBIE 8<\/p>\n
#define VID_MEM 0xB8000
\n#define WHITE_ON_BLACK 0x0F
\n#define GREEN_ON_BLACK 0x0A
\n#define RED_ON_BLACK 0x04<\/p>\n
\/\/ \u8fdb\u7a0b\u4e0a\u4e0b\u6587：\u53ea\u9700\u4fdd\u5b58\u6808\u6307\u9488\u5373\u53ef，\u56e0\u4e3a\u6240\u6709\u901a\u7528\u5bc4\u5b58\u5668\u90fd\u5df2\u7ecf
\n\/\/ \u538b\u5728\u8fd9\u4e2a\u4efb\u52a1\u81ea\u5df1\u7684\u6808\u4e0a\u4e86\u3002
\nstruct context {
\n unsigned int eax;
\n unsigned int ebx;
\n unsigned int ecx;
\n unsigned int edx;
\n unsigned int esi;
\n unsigned int edi;
\n unsigned int ebp;
\n unsigned int esp; \/\/ \u5173\u952e\u5b57\u6bb5：\u88ab\u5207\u6362\u51fa\u53bb\u90a3\u4e00\u523b\u7684\u6808\u6307\u9488
\n unsigned int eip;
\n};<\/p>\n
\/\/ \u8fdb\u7a0b\u63cf\u8ff0\u7b26
\nstruct task_struct {
\n int pid;
\n int state;
\n char comm[16];
\n struct context ctx;
\n};<\/p>\n
struct task_struct p1;
\nstruct task_struct p2;
\nstruct task_struct init_task; \/\/ \u5185\u6838\u4e3b\u7ebf\u7a0b：\u7b2c\u4e00\u6b21\u5207\u6362\u65f6\u7684\u201c\u5f53\u524d\u4efb\u52a1\u201d
\nstruct task_struct *current;<\/p>\n
\/\/ \u6bcf\u4e2a\u4efb\u52a1\u72ec\u7acb\u7684\u5185\u6838\u6808\u9876（\u6808\u5411\u4e0b\u589e\u957f）
\n#define STACK_P1 0x4000
\n#define STACK_P2 0x5000<\/p>\n
\/\/ cpu_switch \u5728\u6808\u4e0a\u4fdd\u5b58\/\u6062\u590d 7 \u4e2a\u901a\u7528\u5bc4\u5b58\u5668 + 1 \u4e2a\u8fd4\u56de\u5730\u5740
\n#define CTX_SLOTS 8<\/p>\n
\/\/ —————- \u663e\u5b58\u8f93\u51fa（C \u76f4\u63a5\u5199 0xB8000） —————-
\nvoid print_str(int row, char *s, char color)
\n{
\n char *v = (char *)VID_MEM + row * 160;
\n while (*s) {
\n *v++ = *s++;
\n *v++ = color;
\n }
\n}<\/p>\n
\/\/ \u628a\u65e0\u7b26\u53f7\u6574\u6570\u6309\u5341\u8fdb\u5236\u5199\u5230\u7b2c row \u884c\u3001\u7b2c col \u5217，\u81f3\u5c11 width \u4f4d（\u53f3\u5bf9\u9f50\u8865 0）
\n\/\/ \u6ca1\u6709 libc，\u6240\u4ee5\u81ea\u5df1\u628a\u6574\u6570\u62c6\u6210\u5b57\u7b26
\nvoid print_uint(int row, int col, unsigned int val, int width, char color)
\n{
\n char *v = (char *)VID_MEM + row * 160 + col * 2;
\n char buf[12];
\n int n = 0;<\/p>\n
do {
\n buf[n++] = (char)('0' + val % 10);
\n val \/= 10;
\n } while (val && n < (int)sizeof(buf));
\n while (n < width && n < (int)sizeof(buf))
\n buf[n++] = '0';<\/p>\n
while (n > 0) {
\n *v++ = buf[–n];
\n *v++ = color;
\n }
\n}<\/p>\n
void clear_screen(void)
\n{
\n char *v = (char *)VID_MEM;
\n for (int i = 0; i < 25 * 80; i++) {
\n *v++ = ' ';
\n *v++ = WHITE_ON_BLACK;
\n }
\n}<\/p>\n
\/\/ \u521d\u59cb\u5316\u4efb\u52a1，\u5e76\u6784\u9020\u201c\u4efb\u52a1\u7b2c\u4e00\u6b21\u88ab\u8c03\u5ea6\u201d\u65f6\u7684\u521d\u59cb\u6808\u3002
\n\/\/ \u6808\u5e03\u5c40（\u4f4e\u5730\u5740 -> \u9ad8\u5730\u5740），\u6b63\u597d\u5bf9\u5e94 cpu_switch \u91cc\u7684 pop \u987a\u5e8f：
\n\/\/ [esp+0]=ebp [esp+4]=edi [esp+8]=esi [esp+12]=edx
\n\/\/ [esp+16]=ecx [esp+20]=ebx [esp+24]=eax [esp+28]=\u5165\u53e3\u5730\u5740
\n\/\/ \u8fd9\u6837 switch_to \u6062\u590d\u5b8c\u5bc4\u5b58\u5668\u540e\u6267\u884c ret，\u5c31\u4f1a\u8df3\u5230\u4efb\u52a1\u5165\u53e3\u51fd\u6570\u3002
\nstatic void task_init(struct task_struct *t, int pid, const char *name,
\n void (*entry)(void), unsigned int stack_top)
\n{
\n unsigned int *sp = (unsigned int *)(stack_top – CTX_SLOTS * 4);
\n int i;<\/p>\n
t->pid = pid;
\n t->state = TASK_RUNNING;
\n for (i = 0; i < 15 && name[i]; i++)
\n t->comm[i] = name[i];
\n t->comm[i] = '\\\\0';<\/p>\n
for (i = 0; i < CTX_SLOTS – 1; i++)
\n sp[i] = 0; \/\/ 7 \u4e2a\u901a\u7528\u5bc4\u5b58\u5668\u7684\u521d\u503c
\n sp[CTX_SLOTS – 1] = (unsigned int)entry; \/\/ ret \u7684\u76ee\u6807 = \u4efb\u52a1\u5165\u53e3<\/p>\n
t->ctx.esp = (unsigned int)sp; \/\/ \u7b2c\u4e00\u6b21\u5207\u6362\u65f6\u4ece\u8fd9\u91cc\u5f00\u59cb pop
\n t->ctx.eip = (unsigned int)entry;
\n}<\/p>\n
\/\/ —————- \u4e0a\u4e0b\u6587\u5207\u6362 —————-
\n\/\/ \u771f\u6b63\u5e72\u6d3b\u7684\u662f cpu_switch：
\n\/\/ 1) \u628a\u5f53\u524d\u4efb\u52a1\u7684 7 \u4e2a\u901a\u7528\u5bc4\u5b58\u5668\u538b\u5230\u5b83\u81ea\u5df1\u7684\u6808\u4e0a，\u5e76\u4fdd\u5b58\u6b64\u65f6\u7684\u6808\u6307\u9488
\n\/\/ 2) \u6362\u4e0a\u76ee\u6807\u4efb\u52a1\u7684\u6808\u6307\u9488
\n\/\/ 3) \u6062\u590d\u76ee\u6807\u4efb\u52a1\u7684\u5bc4\u5b58\u5668\u5e76 ret \u2014\u2014 \u56de\u5230\u5b83\u4e0a\u6b21\u88ab\u5207\u8d70\u7684\u201c\u4e0b\u4e00\u6761\u6307\u4ee4\u201d
\n\/\/ \u5173\u952e：cpu_switch \u5fc5\u987b\u662f naked（\u65e0\u6808\u5e27）\u51fd\u6570\u3002
\n\/\/ \u666e\u901a C \u51fd\u6570\u4f1a\u5728\u5bc4\u5b58\u5668\u4e0e\u8fd4\u56de\u5730\u5740\u4e4b\u95f4\u63d2\u5165\u7f16\u8bd1\u5668\u81ea\u5df1\u7684\u6808\u5e27（push ebp \/ sub esp），
\n\/\/ \u8fd9\u6837\u4efb\u52a1\u7b2c\u4e00\u6b21\u542f\u52a8\u8fd8\u80fd\u8dd1，\u4f46\u88ab\u201c\u91cd\u65b0\u8c03\u5ea6\u56de\u6765\u201d\u65f6 ret \u4f1a\u5f39\u5230\u6808\u5e27\u91cc\u7684\u5783\u573e\u5730\u5740\u3002
\n\/\/ task_init \u662f\u6309\u201c\u5bc4\u5b58\u5668\u7d27\u8ddf\u8fd4\u56de\u5730\u5740\u201d\u7684\u5e03\u5c40\u9884\u7f6e\u521d\u59cb\u6808\u7684，\u4e24\u8005\u5fc5\u987b\u4fdd\u6301\u4e00\u81f4\u3002
\n\/\/ \u6ce8\u610f：naked \u51fd\u6570\u4f53\u53ea\u80fd\u5199\u201c\u57fa\u672c\u6c47\u7f16\u201d，\u5bc4\u5b58\u5668\u76f4\u63a5\u5199 %eax，\u4e0d\u7528\u5199\u6210 %%eax\u3002
\n__attribute__((naked))
\nvoid cpu_switch(unsigned int *save_esp, unsigned int new_esp)
\n{
\n __asm__ __volatile__(
\n "pushl %ebp\\\\n\\\\t"
\n "pushl %edi\\\\n\\\\t"
\n "pushl %esi\\\\n\\\\t"
\n "pushl %edx\\\\n\\\\t"
\n "pushl %ecx\\\\n\\\\t"
\n "pushl %ebx\\\\n\\\\t"
\n "pushl %eax\\\\n\\\\t"
\n "movl 32(%esp), %eax\\\\n\\\\t" \/* save_esp（\u8df3\u8fc7 7 \u4e2a\u5bc4\u5b58\u5668 + \u8fd4\u56de\u5730\u5740）*\/
\n "movl %esp, (%eax)\\\\n\\\\t" \/* *save_esp = \u5f53\u524d\u6808\u6307\u9488 *\/
\n "movl 36(%esp), %eax\\\\n\\\\t" \/* new_esp *\/
\n "movl %eax, %esp\\\\n\\\\t" \/* \u5207\u5230\u76ee\u6807\u4efb\u52a1\u6808 *\/
\n "popl %eax\\\\n\\\\t"
\n "popl %ebx\\\\n\\\\t"
\n "popl %ecx\\\\n\\\\t"
\n "popl %edx\\\\n\\\\t"
\n "popl %esi\\\\n\\\\t"
\n "popl %edi\\\\n\\\\t"
\n "popl %ebp\\\\n\\\\t"
\n "ret\\\\n\\\\t" \/* \u56de\u5230\u76ee\u6807\u4efb\u52a1\u4e0a\u6b21\u5207\u8d70\u7684\u8fd4\u56de\u5730\u5740 *\/
\n );
\n}<\/p>\n
\/\/ \u8fdb\u7a0b\u4ee3\u7801\u8c03\u7528\u8fd9\u4e2a：\u66f4\u65b0 current，\u518d\u628a\u201c\u5f53\u524d\u6808\u5730\u5740\u201d\u548c\u201c\u76ee\u6807\u6808\u6307\u9488\u201d\u4ea4\u7ed9 cpu_switch
\nvoid switch_to(struct task_struct *next)
\n{
\n struct task_struct *prev = current;
\n current = next; \/\/ \u5fc5\u987b\u5728\u5207\u6362\u524d\u66f4\u65b0，\u56e0\u4e3a\u5207\u8d70\u540e\u4e0d\u4f1a\u518d\u56de\u6765\u6267\u884c
\n cpu_switch(&prev->ctx.esp, next->ctx.esp);
\n}<\/p>\n
\/\/ —————- \u4e24\u4e2a\u8fdb\u7a0b —————-
\n\/\/ counter \u662f\u5404\u81ea\u7684\u5c40\u90e8\u53d8\u91cf，\u5b58\u653e\u5728\u5404\u81ea\u7684\u5185\u6838\u6808\u4e0a，\u6240\u4ee5\u4e24\u4e2a\u8fdb\u7a0b\u4e92\u4e0d\u5f71\u54cd\u3002
\nvoid proc1(void)
\n{
\n unsigned int counter = 0;
\n while (1) {
\n print_str(1, "PID1 Running ", GREEN_ON_BLACK);
\n print_uint(1, 13, counter, 10, GREEN_ON_BLACK);
\n counter++;
\n p1.state = TASK_INTERRUPTIBLE;
\n switch_to(&p2); \/\/ \u4e3b\u52a8\u8ba9\u51fa CPU \u7ed9 proc2
\n p1.state = TASK_RUNNING; \/\/ \u518d\u6b21\u88ab\u8c03\u5ea6\u56de\u6765\u65f6\u4ece\u8fd9\u91cc\u7ee7\u7eed
\n }
\n}<\/p>\n
void proc2(void)
\n{
\n unsigned int counter = 0;
\n while (1) {
\n print_str(2, "PID2 Running ", RED_ON_BLACK);
\n print_uint(2, 13, counter, 10, RED_ON_BLACK);
\n counter++;
\n p2.state = TASK_INTERRUPTIBLE;
\n switch_to(&p1); \/\/ \u4e3b\u52a8\u8ba9\u51fa CPU \u7ed9 proc1
\n p2.state = TASK_RUNNING;
\n }
\n}<\/p>\n
\/\/ —————- C \u5185\u6838\u5165\u53e3 —————-
\nvoid kernel_main(void)
\n{
\n clear_screen();<\/p>\n
task_init(&p1, 1, "proc1", proc1, STACK_P1);
\n task_init(&p2, 2, "proc2", proc2, STACK_P2);<\/p>\n
\/\/ \u5185\u6838\u4e3b\u7ebf\u7a0b\u4e5f\u662f\u4e00\u4e2a\u4efb\u52a1：\u7b2c\u4e00\u6b21 switch_to \u9700\u8981\u4e00\u4e2a\u201cfrom\u201d
\n init_task.pid = 0;
\n init_task.state = TASK_RUNNING;
\n current = &init_task;<\/p>\n
switch_to(&p1); \/\/ \u542f\u52a8\u7b2c\u4e00\u4e2a\u8fdb\u7a0b<\/p>\n
\/\/ \u53ea\u6709\u5f53\u5185\u6838\u4e3b\u7ebf\u7a0b\u88ab\u91cd\u65b0\u8c03\u5ea6\u56de\u6765\u624d\u4f1a\u6267\u884c\u5230\u8fd9\u91cc
\n while (1)
\n __asm__ __volatile__("hlt");
\n}<\/p>\n
kernel.ld<\/p>\n
\u94fe\u63a5\u811a\u672c\u3002\u6240\u6709\u6bb5\u4ece 0x1000 \u8d77\u8fde\u7eed\u6392\u5e03，\u6574\u4f53\u4fdd\u6301\u5728 0x3000 \u4ee5\u4e0b，
\n\u907f\u514d\u4e0e\u6808\u3001\u9875\u8868\u51b2\u7a81\u3002<\/p>\n
\/* kernel.ld \u94fe\u63a5\u811a\u672c
\n * \u6240\u6709\u6bb5\u4ece 0x1000 \u5f00\u59cb\u8fde\u7eed\u6392\u5e03，\u6574\u4f53\u4fdd\u6301\u5728 0x3000 \u4ee5\u4e0b，
\n * \u907f\u514d\u548c\u5185\u6838\u5bf9\u6808(0x3000~0x6000)\u3001\u9875\u76ee\u5f55\/\u9875\u8868(0x10000\/0x11000)\u51b2\u7a81\u3002
\n *\/
\nENTRY(start);<\/p>\n
SECTIONS {
\n . = 0x1000; \/* \u52a0\u8f7d\u5230\u7269\u7406\u5730\u57400x1000，\u548cboot\u7684jmp\u76ee\u6807\u5339\u914d *\/<\/p>\n
.text : {
\n *(.boot)
\n *(.text)
\n *(.text.*)
\n }<\/p>\n
.rodata : {
\n *(.rodata)
\n *(.rodata.*)
\n }<\/p>\n
.eh_frame : {
\n *(.eh_frame)
\n }<\/p>\n
.data : {
\n *(.data)
\n *(.data.*)
\n }<\/p>\n
.bss : {
\n *(COMMON)
\n *(.bss)
\n *(.bss.*)
\n }
\n}<\/p>\n
Makefile<\/p>\n
\u6784\u5efa\u811a\u672c：\u6c47\u7f16\u3001\u7f16\u8bd1\u3001\u94fe\u63a5\u3001\u6253\u5305\u955c\u50cf，\u4ee5\u53ca\u8fd0\u884c \/ \u8c03\u8bd5 \/ \u6e05\u7406\u3002<\/p>\n
# Makefile \u2014\u2014 32 \u4f4d\u88f8\u673a\u5185\u6838（\u52a0\u6cb9）
\n# \u4f9d\u8d56：nasm \/ gcc(\u652f\u6301 -m32 \u7f16\u8bd1) \/ ld(binutils) \/ make \/ qemu-system-i386<\/p>\n
CC = gcc
\nAS = nasm
\nLD = ld
\nQEMU = qemu-system-i386<\/p>\n
# freestanding：\u4e0d\u8fde libc；-m32 \u751f\u6210 32 \u4f4d\u4ee3\u7801
\n# -fno-stack-protector \u88f8\u673a\u6ca1\u6709 __stack_chk_fail，\u5fc5\u987b\u5173\u6389\u6808\u4fdd\u62a4
\n# -fno-asynchronous-unwind-tables \u4e0d\u751f\u6210 .eh_frame，\u51cf\u5c0f\u955c\u50cf\u4f53\u79ef
\nCFLAGS = -m32 -ffreestanding -c -g -fno-pic -fno-pie -fno-plt \\\\
\n -fno-stack-protector -fno-asynchronous-unwind-tables
\nASFLAGS_BIN = -f bin
\nASFLAGS_ELF32 = -f elf32
\nLDSCRIPT = kernel.ld<\/p>\n
OBJS = loader.o kernel.o
\nIMG = os.img<\/p>\n
# \u6240\u6709\u7531\u6784\u5efa\u751f\u6210\u7684\u4ea7\u7269（make clean \u65f6\u4e00\u5e76\u5220\u9664）
\nGENERATED = boot.bin loader.o kernel.o kernel.elf kernel.bin $(IMG)<\/p>\n
.PHONY: all clean rebuild run debug<\/p>\n
all: $(IMG)<\/p>\n
kernel.bin kernel.elf: $(OBJS) $(LDSCRIPT)
\n$(LD) -m elf_i386 -T $(LDSCRIPT) $(OBJS) -o kernel.elf
\n$(LD) -m elf_i386 -T $(LDSCRIPT) –oformat binary $(OBJS) -o kernel.bin<\/p>\n
loader.o: loader.asm
\n$(AS) $(ASFLAGS_ELF32) loader.asm -o loader.o<\/p>\n
kernel.o: kernel.c
\n$(CC) $(CFLAGS) kernel.c -o kernel.o<\/p>\n
boot.bin: boot.asm
\n$(AS) $(ASFLAGS_BIN) boot.asm -o boot.bin<\/p>\n
$(IMG): boot.bin kernel.bin
\ndd if=\/dev\/zero of=$(IMG) bs=512 count=2880
\ndd if=boot.bin of=$(IMG) conv=notrunc
\ndd if=kernel.bin of=$(IMG) bs=512 seek=1 conv=notrunc<\/p>\n
# \u5220\u9664\u5168\u90e8\u7f16\u8bd1\u4ea7\u7269（.o \/ .bin \/ .elf \/ os.img）
\nclean:
\nrm -f $(GENERATED)<\/p>\n
# \u4e00\u6b65\u5b8c\u6210：\u5148\u6e05\u5e72\u51c0，\u518d\u91cd\u65b0\u7f16\u8bd1
\nrebuild:
\n$(MAKE) clean
\n$(MAKE) all<\/p>\n
# \u542f\u52a8 QEMU \u8fd0\u884c\u5185\u6838
\nrun: $(IMG)
\n$(QEMU) -drive format=raw,file=$(IMG)<\/p>\n
# \u542f\u52a8 QEMU \u5e76\u505c\u5728\u8d77\u70b9\u7b49\u5f85 gdb \u8fde\u63a5（gdb: target remote :1234）
\ndebug: $(IMG)
\n$(QEMU) -s -S -drive format=raw,file=$(IMG)<\/p>\n
\u751f\u6210\u7684\u6587\u4ef6（make clean \u4f1a\u5168\u90e8\u5220\u9664）
\n\u00a0 \u00a0 boot.bin \u00a0 \u00a0 \u00a0boot.asm \u6c47\u7f16\u51fa\u7684 512 \u5b57\u8282\u5f15\u5bfc\u6247\u533a\u3002
\n\u00a0 \u00a0 loader.o \u00a0 \u00a0 \u00a0loader.asm \u7684 32 \u4f4d ELF \u76ee\u6807\u6587\u4ef6\u3002
\n\u00a0 \u00a0 kernel.o \u00a0 \u00a0 \u00a0kernel.c \u7684 32 \u4f4d\u76ee\u6807\u6587\u4ef6\u3002
\n\u00a0 \u00a0 kernel.elf \u00a0 \u00a0\u5e26\u7b26\u53f7\u4fe1\u606f\u7684 ELF，\u7528\u4e8e objdump \/ gdb \u8c03\u8bd5\u3002
\n\u00a0 \u00a0 kernel.bin \u00a0 \u00a0\u7eaf\u4e8c\u8fdb\u5236\u5185\u6838\u955c\u50cf，\u88ab\u5199\u5165\u78c1\u76d8\u3002
\n\u00a0 \u00a0 os.img \u00a0 \u00a0 \u00a0 \u00a01.44MB \u8f6f\u76d8\u955c\u50cf：\u7b2c 0 \u6247\u533a\u662f boot.bin，\u7b2c 1 \u6247\u533a\u8d77\u662f kernel.bin\u3002<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/10\/20261003234107-6ac192938ae99.png\")
<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5185\u6838\u5b66\u4e60\u7b2c\u4e8c\u5377 \u00b7 \u8fdb\u7a0b（1.）\u6587\u6863\u8bf4\u660e\u672c\u6587\u6863\u662f\u72ec\u7acb\u5b9e\u73b0\u5185\u6838，\u5e76\u4e14\u8bb0\u5f55\u5185\u6838\u5b66\u4e60\u8fc7\u7a0b，\u4ee5\u5e2e\u52a9\u540e\u6765\u7684\u5b66\u4e60\u8005\u6765\u7406\u89e3\u548c\u5b9e\u73b0\u5185\u6838，\u5982\u679c\u6709\u8bb2\u89e3\u4e0d\u6e05\u695a\u7684\u5730\u65b9\u8bf7\u89c1\u8c05\u3002（2.）\u7ec4\u4ef6\u5206\u6790#ifndef PROCESS_DEFS_H
\n#define PROCESS_DEFS_H\/\/ \u524d\u7f6e\u58f0\u660e
\nstruct task_struct;
\nstruct exec_domain;\/\/ \u5b8c\u6574\u5b9a\u4e49 restart_<\/p>\n","protected":false},"author":2,"featured_media":112604,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[12805,58,16,43,44],"topic":[],"class_list":["post-112606","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-12805","tag-linux","tag-16","tag-43","tag-44"],"yoast_head":"\n