test/trace_processor/network/kfree_skb.textproto

packet {
  ftrace_events {
    cpu: 2
    event {
      timestamp: 10000
      pid: 200
      kfree_skb {
      }
    }
  }
}
packet {
  ftrace_events {
    cpu: 2
    event {
      timestamp: 10020
      pid: 300
      kfree_skb {
      }
    }
  }
}
packet {
  ftrace_events {
    cpu: 2
    event {
      timestamp: 20000
      pid: 200
      kfree_skb {
      }
    }
  }
}
packet {
  ftrace_events {
    cpu: 2
    event {
      timestamp: 20020
      pid: 300
      kfree_skb {
      }
    }
  }
}