[PATCH] ipconfig: make the wait for carrier timeout configurable

[PATCH] ipconfig: make the wait for carrier timeout configurable

[Martin Kepplinger]

From: Manfred Schlaegl <manfred.schlaegl@ginzinger.com>

commit 3fb72f1e6e61 ("ipconfig wait for carrier") added a
"wait for carrier" policy, with a fixed worst case maximum wait
of two minutes.

This makes the wait for carrier timeout configurable (0 - 240 seconds).

The informative timeout messages introduced with
commit 5e404cd65860 ("ipconfig: add informative timeout messages while
waiting for carrier") were adapted. Message output is done in a fixed
interval of 20 seconds, just like before (240/12).

Signed-off-by: Manfred Schlaegl <manfred.schlaegl@ginzinger.com>
Signed-off-by: Martin Kepplinger <martin.kepplinger@ginzinger.com>
---

This is really just something we always set shorter on embedded devices
and don't understand why it isn't configurable :)

thanks

                              martin



 net/ipv4/Kconfig    | 11 +++++++++++
 net/ipv4/ipconfig.c |  7 ++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 32cae39cdff6..299c5dbbea97 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -113,6 +113,17 @@ config IP_PNP
 	  on NFS" as well), because all other machines configure the network
 	  in their startup scripts.
 
+config IP_PNP_CARRIER_TIMEOUT
+	int "Wait for carrier timeout (in seconds)"
+	default 120
+	range 0 240
+	depends on IP_PNP
+	help
+	  This defines the timeout waiting for carrier in seconds before
+	  continuing kernel startup.
+
+	  Use the default if unsure.
+
 config IP_PNP_DHCP
 	bool "IP: DHCP support"
 	depends on IP_PNP
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index b9a9873c25c6..e8041c0c2b97 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -85,7 +85,8 @@
 
 /* Define the friendly delay before and after opening net devices */
 #define CONF_POST_OPEN		10	/* After opening: 10 msecs */
-#define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
+/* Wait for carrier timeout */
+#define CONF_CARRIER_TIMEOUT	(CONFIG_IP_PNP_CARRIER_TIMEOUT*1000)
 
 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
@@ -268,7 +269,7 @@ static int __init ic_open_devs(void)
 
 	/* wait for a carrier on at least one device */
 	start = jiffies;
-	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
+	next_msg = start + msecs_to_jiffies(20000);
 	while (time_before(jiffies, start +
 			   msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
 		int wait, elapsed;
@@ -285,7 +286,7 @@ static int __init ic_open_devs(void)
 		elapsed = jiffies_to_msecs(jiffies - start);
 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
 		pr_info("Waiting up to %d more seconds for network.\n", wait);
-		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
+		next_msg = jiffies + msecs_to_jiffies(20000);
 	}
 have_carrier:
 	rtnl_unlock();
-- 
2.20.1

Re: [PATCH] ipconfig: make the wait for carrier timeout configurable

[David Miller]

From: Martin Kepplinger <martink@posteo.de>
Date: Mon, 28 Jan 2019 12:30:05 +0100

> From: Manfred Schlaegl <manfred.schlaegl@ginzinger.com>
> 
> commit 3fb72f1e6e61 ("ipconfig wait for carrier") added a
> "wait for carrier" policy, with a fixed worst case maximum wait
> of two minutes.
> 
> This makes the wait for carrier timeout configurable (0 - 240 seconds).
> 
> The informative timeout messages introduced with
> commit 5e404cd65860 ("ipconfig: add informative timeout messages while
> waiting for carrier") were adapted. Message output is done in a fixed
> interval of 20 seconds, just like before (240/12).
> 
> Signed-off-by: Manfred Schlaegl <manfred.schlaegl@ginzinger.com>
> Signed-off-by: Martin Kepplinger <martin.kepplinger@ginzinger.com>

I would prefer that this be implemented using a kernel command line
parameter.

That way you don't need to rebuild the kernel to adjust the value.

Thanks.