fix sockops description error

Author: yunwei37

src/29-sockops/README.md

@@ -181,32 +181,41 @@ sudo bpftool prog attach pinned /sys/fs/bpf/bpf_redir msg_verdict pinned /sys/fs
 
 ```console
 $ sudo bpftool prog show
-63: sock_ops  name bpf_sockmap  tag 275467be1d69253d  gpl
+63: sock_ops  name bpf_sockops_handler  tag 275467be1d69253d  gpl
  loaded_at 2019-01-24T13:07:17+0200  uid 0
  xlated 1232B  jited 750B  memlock 4096B  map_ids 58
 64: sk_msg  name bpf_redir  tag bc78074aa9dd96f4  gpl
  loaded_at 2019-01-24T13:07:17+0200  uid 0
  xlated 304B  jited 233B  memlock 4096B  map_ids 58
 ```
 
-### 运行 [iperf3](https://iperf.fr/) 服务器
+### 使用 iperf3 或 curl 进行测试
+
+运行 [iperf3](https://iperf.fr/) 服务器
 
 ```shell
 iperf3 -s -p 5001
 ```
 
-### 运行 [iperf3](https://iperf.fr/) 客户端
+运行 [iperf3](https://iperf.fr/) 客户端
 
 ```shell
 iperf3 -c 127.0.0.1 -t 10 -l 64k -p 5001
 ```
 
+或者也可以用 Python 和 curl 进行测试：
+
+```sh
+python3 -m http.server
+curl http://0.0.0.0:8000/
+```
+
 ### 收集追踪
 
 查看``sock_ops``追踪本地连接建立
 
 ```console
-$ ./trace_bpf_output.sh
+$ ./trace_bpf_output.sh # 实际上就是 sudo cat /sys/kernel/debug/tracing/trace_pipe
 iperf3-9516  [001] .... 22500.634108: 0: <<< ipv4 op = 4, port 18583 --> 4135
 iperf3-9516  [001] ..s1 22500.634137: 0: <<< ipv4 op = 5, port 4135 --> 18583
 iperf3-9516  [001] .... 22500.634523: 0: <<< ipv4 op = 4, port 19095 --> 4135
@@ -215,10 +224,10 @@ iperf3-9516  [001] ..s1 22500.634536: 0: <<< ipv4 op = 5, port 4135 --> 19095
 
 当iperf3 -c建立连接后，你应该可以看到上述用于套接字建立的事件。如果你没有看到任何事件，那么 eBPF 程序可能没有正确地附加上。
 
-此外，当``sk_msg``生效后，可以发现当使用tcpdump捕捉本地lo设备流量时，只能捕获三次握手和四次挥手流量，而iperf数据流量没有被捕获到。如果捕获到iperf数据流量，那么 eBPF 程序可能没有正确地附加上。
+此外，当``sk_msg``生效后，可以发现当使用 tcpdump 捕捉本地lo设备流量时，只能捕获三次握手和四次挥手流量，而iperf数据流量没有被捕获到。如果捕获到iperf数据流量，那么 eBPF 程序可能没有正确地附加上。
 
 ```console
-$ ./trace_lo_traffic.sh # 实际上就是 sudo cat /sys/kernel/debug/tracing/trace_pipe
+$ ./trace_lo_traffic.sh # tcpdump -i lo port 5001
 
 # 三次握手
 13:24:07.181804 IP localhost.46506 > localhost.5001: Flags [S], seq 620239881, win 65495, options [mss 65495,sackOK,TS val 1982813394 ecr 0,nop,wscale 7], length 0

src/29-sockops/README_en.md

@@ -189,24 +189,35 @@ $ sudo bpftool prog show
  xlated 304B  jited 233B  memlock 4096B  map_ids 58
 ```
 
-### Running the iperf3 Server
+### Test with iperf3 or curl
+
+See <https://iperf.fr/> to install iperf3.
+
+Running the iperf3 Server:
 
 ```shell
 iperf3 -s -p 5001
 ```
 
-### Running the iperf3 Client
+Running the iperf3 Client:
 
 ```shell
 iperf3 -c 127.0.0.1 -t 10 -l 64k -p 5001
 ```
 
+Or you can use curl and python:
+
+```sh
+python3 -m http.server
+curl http://0.0.0.0:8000/
+```
+
 ### Collecting Traces
 
 Check the `sock_ops` trace for local connection establishments.
 
 ```console
-$ ./trace_bpf_output.sh
+$ ./trace_bpf_output.sh # which is basically sudo cat /sys/kernel/debug/tracing/trace_pipe
 iperf3-9516  [001] .... 22500.634108: 0: <<< ipv4 op = 4, port 18583 --> 4135
 iperf3-9516  [001] ..s1 22500.634137: 0: <<< ipv4 op = 5, port 4135 --> 18583
 iperf3-9516  [001] .... 22500.634523: 0: <<< ipv4 op = 4, port 19095 --> 4135
@@ -218,7 +229,7 @@ When the connection is established between `iperf3 -c` and the server, you shoul
 Furthermore, when `sk_msg` takes effect, you should observe that when capturing local traffic on the loopback interface using tcpdump, only the three-way handshake and four-way termination traffic are captured, and the actual data flow of iperf is not captured. If the iperf data flow is captured, then the eBPF programs may not have been attached correctly.
 
 ```console
-$ ./trace_lo_traffic.sh # which is basically sudo cat /sys/kernel/debug/tracing/trace_pipe
+$ ./trace_lo_traffic.sh # tcpdump -i lo port 5001
 
 # Three-way handshake
 13:24:07.181804 IP localhost.46506 > localhost.5001: Flags [S], seq 620239881, win 65495, options [mss 65495,sackOK,TS val 1982813394 ecr 0,nop,wscale 7], length 0