How to perform configuration of the ESP32 ? "Data buffer allocation failed" and other errors trying to do so

[joelguittet]

Hello community !

I'm working with an ESP32 board with a custom application.
I'm not able to do some HTTPS client connection with this board (the same application works fine with another board in Zephyr, not an ESP32). I'm trying to port it to the ESP32.

The error I get are the following when connection tries to be established:

[00:00:24.391,000] <err> net_pkt: Data buffer (980) allocation failed (tcp_send_data:1187)
[00:00:24.391,000] <err> net_tcp: conn: 0x3fffce30 packet allocation failed, len=932
[00:00:24.391,000] <err> net_tcp: TCP failed to allocate buffer in retransmission
[00:00:24.492,000] <err> net_pkt: Data buffer (719) allocation failed (tcp_send_data:1187)
[00:00:24.492,000] <err> net_tcp: conn: 0x3fffce30 packet allocation failed, len=671
[00:00:24.592,000] <err> net_pkt: Data buffer (1328) allocation failed (tcp_send_data:1187)
[00:00:24.592,000] <err> net_tcp: conn: 0x3fffce30 packet allocation failed, len=1280

Before that of course wifi has been connected successfully to the AP and I received an IP address.

I have tried to play a bit with some CONFIG looking at various issues in this repo, but nothing really relevant found. Still blocking on this point.

Anyone knowing how to solve this issue ? I would like to understand where are the data buffer allocated, so I can arrange a modification of stack/heap somewhere, but it looks like not so easy to understand this part of the net layer...

Thanks for any advice!
Joel

PS: I'm using Zephyr 3.4.0

[joelguittet]

Update: I have increased CONFIG_HEAP_MEM_POOL_SIZE to 110000 and the above issue dissapears. But then I get another one.

When the my http client tries to connect, this returns -1 with errno=12. I got the following log:

[00:00:31.064,000] <dbg> net_tcp: tcp_conn_ref: (my_app_work_queue): conn: 0x3fffde30, ref_count: 1
[00:00:31.064,000] <dbg> net_tcp: tcp_conn_alloc: (my_app_work_queue): conn: 0x3fffde30
[00:00:31.064,000] <dbg> net_tcp: net_tcp_recv: (my_app_work_queue): context: 0x3ffd1498, cb: 0x400db120, user_data: 0
[00:00:31.065,000] <dbg> net_tcp: net_tcp_connect: (my_app_work_queue): context: 0x3ffd1498, local: 0.0.0.0, remote: 34.192.66.92
0x400db120: zsock_received_cb at /home/ubuntu/zephyrproject/zephyr/subsys/net/lib/sockets/sockets.c:385

[00:00:31.067,000] <dbg> net_tcp: net_tcp_connect: (my_app_work_queue): conn: 0x3fffde30 src: 192.168.1.140, dst: 34.192.66.92
[00:00:31.067,000] <dbg> net_tcp: tcp_in: (my_app_work_queue):  [LISTEN Seq=3188567933 Ack=0]
[00:00:31.068,000] <dbg> net_tcp: tcp_out_ext: (my_app_work_queue): SYN Seq=3188567933 Len=0
[00:00:31.068,000] <dbg> net_tcp: tcp_send_process_no_lock: (my_app_work_queue): SYN Seq=3188567933 Len=0 
[00:00:31.068,000] <dbg> net_tcp: tcp_send: (my_app_work_queue): SYN Seq=3188567933 Len=0
[00:00:31.072,000] <dbg> net_tcp: tcp_in: (my_app_work_queue): LISTEN->SYN_SENT
--- 1 messages dropped ---
[00:00:31.274,000] <dbg> net_tcp: tcp_options_check: (rx_q[0]): len=4
[00:00:31.274,000] <dbg> net_tcp: tcp_options_check: (rx_q[0]): opt: 2, opt_len: 4
[00:00:31.274,000] <dbg> net_tcp: tcp_options_check: (rx_q[0]): MSS=1460
[00:00:31.274,000] <dbg> net_tcp: tcp_in: (rx_q[0]): Lowering send window from 26883 to 1280
[00:00:31.274,000] <dbg> net_tcp: tcp_window_full: (rx_q[0]): conn: 0x3fffde30 window_full=0
[00:00:31.274,000] <dbg> net_tcp: tcp_send_timer_cancel: (rx_q[0]): SYN Seq=3188567933 Len=0
[00:00:31.275,000] <dbg> net_tcp: tcp_conn_ref: (rx_q[0]): conn: 0x3fffde30, ref_count: 2
[00:00:31.275,000] <dbg> net_tcp: tcp_out_ext: (rx_q[0]): ACK Seq=3188567934 Ack=1800611130 Len=0
[00:00:31.275,000] <dbg> net_tcp: tcp_send_process_no_lock: (rx_q[0]): ACK Seq=3188567934 Ack=1800611130 Len=0 
[00:00:31.275,000] <dbg> net_tcp: tcp_send: (rx_q[0]): ACK Seq=3188567934 Ack=1800611130 Len=0
[00:00:31.276,000] <dbg> net_tcp: tcp_in: (rx_q[0]): SYN_SENT->ESTABLISHED
[00:00:31.278,000] <dbg> net_tcp: net_tcp_connect: (my_app_work_queue): conn: 0x3fffde30, ret=0

Really strange error, looks like the connection is established...

So ... don't know really where to go. Is there somewhere a good tutorial / example to use ESP32 with Zephyr ? Not just blinking an LED... but instead doing some real stuff, I mean wifi and TCP/UDP connections working.

[sylvioalves]

@joelguittet, please, enable SHELL and run kernel stacks. Take a look and verify if there is any full stack being used. Then increased it. I guess below items might need some adjustment:

CONFIG_NET_MGMT_EVENT_QUEUE_SIZE=10
CONFIG_NET_TCP_WORKQ_STACK_SIZE=2048

[joelguittet]

Hello @sylvioalves
Thanks for pointing this, I was not checking this part because I already seen some kernel dump indicating the stack overflowed, but was not there at the moment. I have added these ones and also some few others.
I will try to create a pull request soon by adding the board to the big http download sample so that people are able to use it!