c - 为什么 last_rx 总是 0？

Question

我需要在 net_device 结构中获取字段 last_rx 和 trans_start 的值...但出于某种原因 dev->last_rx 始终为 0(trans_start 具有有效值)...这是为什么？是否有另一个字段提供此值？

这是一个片段

struct net_device *dev;
dev = first_net_device(&init_net);

while (dev)
{

        printk(KERN_ALERT "last received time is %li\n", dev->last_rx );
        printk(KERN_ALERT "last transmit time is %li\n", dev->trans_start );
        dev = next_net_device(dev);
}

我正在使用 linux 内核 2.6.35 编写内核模块

Answer 1

我简单的补充了 dev->last_rx = jiffies; 它奏效了! :D

struct net_device *dev;
dev = first_net_device(&init_net);

while (dev)
{

        dev->last_rx = jiffies;
        printk(KERN_ALERT "last received time is %li\n", dev->last_rx );
        printk(KERN_ALERT "last transmit time is %li\n", dev->trans_start );
        dev = next_net_device(dev);
}