From f886476139da26762e252834007d02af4881f589 Mon Sep 17 00:00:00 2001
From: ridethepig <protonghost@163.com>
Date: Wed, 23 Nov 2022 22:54:45 +0800
Subject: [PATCH] forkbomb over 10W, god knows still some conflicts?

---
 kern/fork.c | 7 +++++--
 kern/wait.c | 7 +++----
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/kern/fork.c b/kern/fork.c
index b42b4d0..479e3bd 100644
--- a/kern/fork.c
+++ b/kern/fork.c
@@ -127,6 +127,8 @@ kern_fork(PROCESS_0 *p_fa)
 		xchg(&p_fa->lock, 0);
 		return -EAGAIN;
 	}
+	while (xchg(&proc_child->pcb.lock, 1) == 1)
+		schedule();
 	PROCESS_0 *p_child = &proc_child->pcb;
 	// 再之后你需要做的是好好阅读一下pcb的数据结构，搞明白结构体中每个成员的语义
 	// 别光扫一遍，要搞明白这个成员到底在哪里被用到了，具体是怎么用的
@@ -154,17 +156,17 @@ kern_fork(PROCESS_0 *p_fa)
 	p_child->exit_code = p_fa->exit_code;
 	// p_child->fork_tree
 	// p_child->kern_regs
-	p_child->lock = 0;
+	// p_child->lock
 	// p_child->page_list
 	p_child->pid = i;
 	p_child->priority = p_fa->priority;
 	p_child->statu = INITING; //! important!!! if you copied this from parent, haha, waste one hour
 	p_child->ticks = p_fa->ticks;
 	p_child->user_regs = p_fa->user_regs;
+	ENABLE_INT();
 	//?   2. ALLOC PAGES AND COPY PHYSICAL MEMORY
 	copy_parent_pages(p_child, p_fa);
 	// panic("Unimplement! soul torture1");
-	ENABLE_INT();
 	//?   3. SET restart point
 	// //! maybe, kern stack different, use offset relevant to stack base addr to set child's kern esp
 	// u32 esp_off = p_fa->kern_regs.esp - (u32)p_fa;
@@ -196,6 +198,7 @@ kern_fork(PROCESS_0 *p_fa)
 	p_fa->fork_tree.sons = p_son;
 	// 最后你需要将子进程的状态置为READY，说明fork已经好了，子进程准备就绪了
 	p_child->statu = READY;
+	xchg(&p_child->lock, 0);
 	xchg(&p_fa->lock, 0);
 	// 在你写完fork代码时先别急着运行跑，先要对自己来个灵魂拷问
 	// 1. 上锁上了吗？所有临界情况都考虑到了吗？（永远要相信有各种奇奇怪怪的并发问题）
diff --git a/kern/wait.c b/kern/wait.c
index 94992f6..e958e5d 100644
--- a/kern/wait.c
+++ b/kern/wait.c
@@ -33,12 +33,11 @@ kern_wait(int *wstatus)
 	// wait系统调用与exit系统调用关系密切，所以在实现wait之前需要先读一遍exit为好
 	// 可能读完exit的代码你可能知道wait该具体做什么了
 	// panic("Unimplement! Read The F**king Source Code");
-
+again:
+	while (xchg(&p_proc_ready->pcb.lock, 1) == 1)
+		schedule();
 	PROCESS_0 *p_fa = &p_proc_ready->pcb;
 	int child_pid = -1;
-again:
-	while (xchg(&p_fa->lock, 1) == 1)
-		schedule();
 	struct son_node* p_son = p_fa->fork_tree.sons;
 	if (p_son == NULL) {
 		xchg(&p_fa->lock, 0);