package main

import (
	"fmt"
	"runtime"
	"sync"
	"time"
)

func testSyncHandoff() {
	runtime.GOMAXPROCS(1)
	var wg sync.WaitGroup
	var mu sync.Mutex

	// 启动G1：持有锁并阻塞
	wg.Add(1)
	go func() {
		defer wg.Done()
		mu.Lock()
		defer mu.Unlock()
		fmt.Println("G1: 获取锁，开始阻塞（1s）")
		time.Sleep(1 * time.Second) // 同步阻塞
		fmt.Println("G1: 释放锁，执行完成")
	}()

	// 启动G2：尝试获取锁，触发Hand Off
	wg.Add(1)
	go func() {
		defer wg.Done()
		fmt.Println("G2: 尝试获取锁...")
		mu.Lock()
		defer mu.Unlock()
		fmt.Println("G2: 获取锁，执行完成")
	}()

	wg.Wait()
	fmt.Println("同步阻塞Hand Off验证结束")
}

func main() {
	runtime.GOMAXPROCS(1)
	fmt.Printf("当前P的数量: %d\n", runtime.GOMAXPROCS(0))
	// testSyscallHandoff() // 注释或取消注释切换测试
	testSyncHandoff()
}