Re: [Linux-ATM-General] Fwd: Re: [PATCH] pppoatm carrier status

[Karl H. <ka...@hi...>]

On 09/23/10 19:02, Philip Prindeville wrote:

> What I'm seeing in user-space is:
> 
>>>>>  Link up
> pbx2 ~ # ip link show ppp0
> 8: ppp0:<POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP>  mtu 1500 qdisc
> pfifo_fast state UNKNOWN qlen 3
>     link/ppp
> 
>>>>>  cable unplugged
> pbx2 ~ # ip link show ppp0
> 8: ppp0:<POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP>  mtu 1500 qdisc
> pfifo_fast state UNKNOWN qlen 3
>     link/ppp
> pbx2 ~ # ip link show ppp0
> 8: ppp0:<POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP>  mtu 1500 qdisc
> pfifo_fast state UNKNOWN qlen 3
>     link/ppp
> pbx2 ~ # ip link show ppp0
> 8: ppp0:<POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP>  mtu 1500 qdisc
> pfifo_fast state UNKNOWN qlen 3
>     link/ppp
> 
>>>>>  cable plugged back in, carrier restored
> pbx2 ~ # ip link show ppp0
> 22: ppp0:<POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP>  mtu 1500 qdisc
> pfifo_fast state UNKNOWN qlen 3
>     link/ppp
> pbx2 ~ #
>  

so LOWER_UP is not changing....


> What's the "8" vs. "22"?  (And is 3 an appropriate queue length?)



Those are the interface indexes.  When  you create a new interface you
get a new index.  One way to read this in userspace is to see "man
if_nametoindex".  qlen 3 is pretty small on a DSL line with a high
upload speed.. I usually use between 10 and 100. It also depends a lot
on your DSL hardware and how much internal buffering/queuing it has, and
how much other load is on your system.  On a xscale 266mhz router with
DSL with 1mbit upload, i needed qlen closer to 100 to max out the line,
when the machine was also saturated with IRQs comming from network
interfaces, CompatFlash on PCI bus, and other hardware.


New patch attached that should fix the "scheduling while atomic". I also
added a bunch of debug printk's so we can hopefully figure out what is
happening.   Send the dmesg output when un/plugging the cable.   I
assume the solos-pci driver does this well and calls
atm_dev_signal_change().

--
Karl