[PATCH v2 1/5] net: lwip: call sys_check_timeouts and schedule on rx

[Heinrich Schuchardt]

On 5/30/25 17:38, Tim Harvey wrote:
> Call schedule() in net_lwip_rx() to service U-Boot tasks and
> actions during packet rx.
> 
> As a cleanup also move sys_check_timeouts() here and remove it from the
> functions that call net_lwip_rx().
> 
> This resolves the issue of an active watchdog resetting the board on
> long network activities.
> 
> Suggested-by: Jerome Forissier <jerome.forissier at linaro.org>
> Signed-off-by: Tim Harvey <tharvey at gateworks.com>
> ---
> v2:
>   - remove duplication of sys_check_timeouts() from functions that call
>     net_lwip_rx()
> ---
>   net/lwip/dhcp.c     | 1 -
>   net/lwip/dns.c      | 1 -
>   net/lwip/net-lwip.c | 7 +++++++
>   net/lwip/ping.c     | 1 -
>   net/lwip/tftp.c     | 1 -
>   net/lwip/wget.c     | 1 -
>   6 files changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/net/lwip/dhcp.c b/net/lwip/dhcp.c
> index 92bd7067a7fb..b79b746db390 100644
> --- a/net/lwip/dhcp.c
> +++ b/net/lwip/dhcp.c
> @@ -57,7 +57,6 @@ static int dhcp_loop(struct udevice *udev)
>   	/* Wait for DHCP to complete */
>   	do {
>   		net_lwip_rx(udev, netif);
> -		sys_check_timeouts();
>   		bound = dhcp_supplied_address(netif);
>   		if (bound)
>   			break;
> diff --git a/net/lwip/dns.c b/net/lwip/dns.c
> index 19172ac959ac..738f8bf3196b 100644
> --- a/net/lwip/dns.c
> +++ b/net/lwip/dns.c
> @@ -91,7 +91,6 @@ static int dns_loop(struct udevice *udev, const char *name, const char *var)
>   			net_lwip_rx(udev, netif);
>   			if (dns_cb_arg.done)
>   				break;
> -			sys_check_timeouts();
>   			if (ctrlc()) {
>   				printf("\nAbort\n");
>   				break;
> diff --git a/net/lwip/net-lwip.c b/net/lwip/net-lwip.c
> index f05c4cd3f64f..e8d4cc542ed8 100644
> --- a/net/lwip/net-lwip.c
> +++ b/net/lwip/net-lwip.c
> @@ -13,8 +13,10 @@
>   #include <lwip/etharp.h>
>   #include <lwip/init.h>
>   #include <lwip/prot/etharp.h>
> +#include <lwip/timeouts.h>
>   #include <net.h>
>   #include <timer.h>
> +#include <u-boot/schedule.h>
>   
>   /* xx:xx:xx:xx:xx:xx\0 */
>   #define MAC_ADDR_STRLEN 18
> @@ -284,6 +286,11 @@ int net_lwip_rx(struct udevice *udev, struct netif *netif)
>   	int len;
>   	int i;
>   
> +	/* lwIP timers */
> +	sys_check_timeouts();
> +	/* Other tasks and actions */
> +	schedule(

Some scheduled tasks have a long duration, specifically video_sync_all() 
called via video_idle(). This change will lead to lost packages.


@Tom, Simon

The EFI code was impacted by 29caf9305b6f ("cyclic: Use schedule() 
instead of WATCHDOG_RESET()"). This added schedule() calls to EFI 
networking. Package losses can expected if schedule() takes more than 1 
µs. This is much shorter than the time needed for synchronizing a 1 MiB 
frame buffer. The cyclic framework was explicitly meant for short 
duration function calls, not for long duration tasks like syncing the 
video frame buffer.


I think we should remove video_idle() from the cyclic framework. 
video_sync_all() should only be triggered if there is video output.

Best regards

Heinrich

> +
>   	if (!eth_is_active(udev))
>   		return -EINVAL;
>   
> diff --git a/net/lwip/ping.c b/net/lwip/ping.c
> index d8042ceecf99..1390b914f7d8 100644
> --- a/net/lwip/ping.c
> +++ b/net/lwip/ping.c
> @@ -136,7 +136,6 @@ static int ping_loop(struct udevice *udev, const ip_addr_t *addr)
>   	ping_send(&ctx);
>   
>   	do {
> -		sys_check_timeouts();
>   		net_lwip_rx(udev, netif);
>   		if (ctx.alive)
>   			break;
> diff --git a/net/lwip/tftp.c b/net/lwip/tftp.c
> index fae701bad2eb..7495dc077ba5 100644
> --- a/net/lwip/tftp.c
> +++ b/net/lwip/tftp.c
> @@ -200,7 +200,6 @@ static int tftp_loop(struct udevice *udev, ulong addr, char *fname,
>   	sys_timeout(NO_RSP_TIMEOUT_MS, no_response, &ctx);
>   	while (!ctx.done) {
>   		net_lwip_rx(udev, netif);
> -		sys_check_timeouts();
>   		if (ctrlc()) {
>   			printf("\nAbort\n");
>   			ctx.done = ABORTED;
> diff --git a/net/lwip/wget.c b/net/lwip/wget.c
> index ea1113e18b11..fcaf684e61da 100644
> --- a/net/lwip/wget.c
> +++ b/net/lwip/wget.c
> @@ -525,7 +525,6 @@ int wget_do_request(ulong dst_addr, char *uri)
>   
>   	while (!ctx.done) {
>   		net_lwip_rx(udev, netif);
> -		sys_check_timeouts();
>   		if (ctrlc())
>   			break;
>   	}