Re: created new q_disc, inserted module, tc tells me unknown qdisc

Re: created new q_disc, inserted module, tc tells me unknown qdisc

[Stephen Hemminger]

On Mon, 10 Apr 2006 21:41:39 -0400 (EDT)
"George P Nychis" <gnychis@cmu.edu> wrote:

> Hi,
> 
> I am trying to install a proprietary qdisc made for research, it is not publically released yet, however its been used several times so i know it works.
> 
> The files included are:
> q_xcp.c:
>    static int xcp_parse_opt()
>    static int xcp_print_opt()
>    static int xcp_print_xstats()
>    struct qdisc_util xcp_util = { "NULL", "xcp" ..... };
> 
> sch_xcp.c:
>    static int xcp_enqueue()
>    static int xcp_requeue()
>    static struct sk_buff * xcp_dequeue()
>    ....
>    ....
>    struct Qdisc_ops xcp_qdisc_ops ={ NULL,NULL,"xcp",.... };
> 
>    printk(KERN_INFO "XCP qdisc module loaded.\n");
>    return register_qdisc(&xcp_qdisc_ops);
> 
> 
> So, i make everything successfully, it creates q_xcp.so and copies it to /usr/lib and sch_xcp.o which it copies to /lib/modules/... so then I "insmod sch_xcp" and i see in dmesg:
> "XCP qdisc module loaded."
> 
> I then try:
> "tc qdisc add dev eth0 root xcp capacity 10Mbit limit 500" and get:
> "Unknown qdisc "xcp", hence option "capacity" is unparsable"
> 
> So then I read the INSTALL further to find some sort of solution and it mentions:
> This again assumes "tc" version is 2.4.7.  If your "tc" is a different
> version, download the iproute2 source code, and edit Makefile to
> point "TC_INCLUDE" to "-I..../iproute2/include -I..../iproute2/tc"
> 
> So, i did that, and i recompiled the q_xcp.so:
> lanthanum-ini src-1.0.1 # make q_xcp.so
> cc -O2 -fPIC -I/var/tmp/portage/iproute2-2.6.11.20050310-r1/work/iproute2-2.6.11/include/ -I/var/tmp/portage/iproute2-2.6.11.20050310-r1/work/iproute2-2.6.11/tc_include -o q_xcp.o -c q_xcp.c
> ld -shared -o q_xcp.so q_xcp.o
> rm -f q_xcp.o
> 
> But i still get the same error.... so then my very final last effort was to move q_xcp.c to my iproute2 source code tc/ directory and added this to the makefile:
> TCMODULES += q_xcp.o
> 
> Then I compiled tc, and i check tc to see if the xcp qdisc functions were loaded:
> lanthanum-ini tc # nm tc | grep xcp
> 080531ec t xcp_parse_opt
> 080533e0 t xcp_print_opt
> 08053426 t xcp_print_xstats
> 08070cc0 D xcp_util
> 
> And finally:
> lanthanum-ini tc # ./tc qdisc add dev ath0 root xcp capacity 54Mbit limit 500
> Unknown qdisc "xcp", hence option "capacity" is unparsable
> 
> 
> I have no clue :(  I figured that putting the .so into /usr/lib would have been enough.  Sorry for the long e-mail, I hope someone can help, and thank you for your time even if you don't know the solution but read this :)
> 
> - George
> 

The .so needs to go in /usr/lib/tc (assuming you are running relatively recent version
of iproute2 tools).

Read source to tc.c where it calls dlopen.

Re: created new q_disc, inserted module, tc tells me unknown qdisc

[George P Nychis]

> On Mon, 10 Apr 2006 21:41:39 -0400 (EDT) "George P Nychis"
> <gnychis@cmu.edu> wrote:
> 
>> Hi,
>> 
>> I am trying to install a proprietary qdisc made for research, it is not
>> publically released yet, however its been used several times so i know
>> it works.
>> 
>> The files included are: q_xcp.c: static int xcp_parse_opt() static int
>> xcp_print_opt() static int xcp_print_xstats() struct qdisc_util xcp_util
>> = { "NULL", "xcp" ..... };
>> 
>> sch_xcp.c: static int xcp_enqueue() static int xcp_requeue() static struct
>> sk_buff * xcp_dequeue() .... .... struct Qdisc_ops xcp_qdisc_ops ={
>> NULL,NULL,"xcp",.... };
>> 
>> printk(KERN_INFO "XCP qdisc module loaded.\n"); return
>> register_qdisc(&xcp_qdisc_ops);
>> 
>> 
>> So, i make everything successfully, it creates q_xcp.so and copies it
>> to /usr/lib and sch_xcp.o which it copies to /lib/modules/... so then I
>> "insmod sch_xcp" and i see in dmesg: "XCP qdisc module loaded."
>> 
>> I then try: "tc qdisc add dev eth0 root xcp capacity 10Mbit limit 500"
>> and get: "Unknown qdisc "xcp", hence option "capacity" is unparsable"
>> 
>> So then I read the INSTALL further to find some sort of solution and it
>> mentions: This again assumes "tc" version is 2.4.7.  If your "tc" is a
>> different version, download the iproute2 source code, and edit Makefile
>> to point "TC_INCLUDE" to "-I..../iproute2/include -I..../iproute2/tc"
>> 
>> So, i did that, and i recompiled the q_xcp.so: lanthanum-ini src-1.0.1 #
>> make q_xcp.so cc -O2 -fPIC
>> -I/var/tmp/portage/iproute2-2.6.11.20050310-r1/work/iproute2-2.6.11/inc
>> lude/
>> -I/var/tmp/portage/iproute2-2.6.11.20050310-r1/work/iproute2-2.6.11/tc_
>> include -o q_xcp.o -c q_xcp.c ld -shared -o q_xcp.so q_xcp.o rm -f
>> q_xcp.o
>> 
>> But i still get the same error.... so then my very final last effort
>> was to move q_xcp.c to my iproute2 source code tc/ directory and added
>> this to the makefile: TCMODULES += q_xcp.o
>> 
>> Then I compiled tc, and i check tc to see if the xcp qdisc functions
>> were loaded: lanthanum-ini tc # nm tc | grep xcp 080531ec t xcp_parse_opt
>>  080533e0 t xcp_print_opt 08053426 t xcp_print_xstats 08070cc0 D xcp_util
>> 
>> 
>> And finally: lanthanum-ini tc # ./tc qdisc add dev ath0 root xcp
>> capacity 54Mbit limit 500 Unknown qdisc "xcp", hence option "capacity"
>> is unparsable
>> 
>> 
>> I have no clue :(  I figured that putting the .so into /usr/lib would
>> have been enough.  Sorry for the long e-mail, I hope someone can help,
>> and thank you for your time even if you don't know the solution but
>> read this :)
>> 
>> - George
>> 
> 
> The .so needs to go in /usr/lib/tc (assuming you are running relatively
> recent version of iproute2 tools).
> 
> Read source to tc.c where it calls dlopen.
> 
> 

Still didn't seem to solve the problem :\

In my tc.c i have:
   snprintf(buf, sizeof(buf), "/usr/lib/tc/q_%s.so", str);

Also:
lanthanum-ini tc # ls /usr/lib/tc
experimental.dist  normal.dist  pareto.dist  paretonormal.dist  q_netem.so  q_xcp.so

And finally:
lanthanum-ini tc # tc qdisc add dev ath0 root xcp capacity 54Mbit limit 500
Unknown qdisc "xcp", hence option "capacity" is unparsable

Maybe i should add debugging in tc.c and see if it sees the .so and fails to load it or something.

Any other suggestions?

Thanks for all the responses,
George

Re: Re: created new q_disc, inserted module, tc tells me unknown qdisc

[George P Nychis]

I am getting closer...

I added debugging, and noticed that it looks for:
       snprintf(buf, sizeof(buf), "%s_qdisc_util", str);

However in q_xcp.c it had:
       struct qdisc_util xcp_util = {

so I changed that to xcp_qdisc_util, and now i run tc:
lanthanum-ini tc # tc qdisc add dev ath0 root xcp capacity 54Mbit limit 100
Segmentation fault

This happens on this line:
 q = dlsym(dlh, buf);

Since this is very hard for people to help me without the source code, i did ask the author if it has been release publically and am waiting for a response.  In the meantime, it seems as though maybe instead of trying to get this to work with a newer version of tc, i should install an old version of tc that the module was original made for.

Though if anyone else has ideas let me know.

Thanks for all the help

- George


>> On Mon, 10 Apr 2006 21:41:39 -0400 (EDT) "George P Nychis" 
>> <gnychis@cmu.edu> wrote:
>> 
>>> Hi,
>>> 
>>> I am trying to install a proprietary qdisc made for research, it is
>>> not publically released yet, however its been used several times so i
>>> know it works.
>>> 
>>> The files included are: q_xcp.c: static int xcp_parse_opt() static
>>> int xcp_print_opt() static int xcp_print_xstats() struct qdisc_util
>>> xcp_util = { "NULL", "xcp" ..... };
>>> 
>>> sch_xcp.c: static int xcp_enqueue() static int xcp_requeue() static
>>> struct sk_buff * xcp_dequeue() .... .... struct Qdisc_ops
>>> xcp_qdisc_ops ={ NULL,NULL,"xcp",.... };
>>> 
>>> printk(KERN_INFO "XCP qdisc module loaded.\n"); return 
>>> register_qdisc(&xcp_qdisc_ops);
>>> 
>>> 
>>> So, i make everything successfully, it creates q_xcp.so and copies it
>>>  to /usr/lib and sch_xcp.o which it copies to /lib/modules/... so
>>> then I "insmod sch_xcp" and i see in dmesg: "XCP qdisc module loaded."
>>> 
>>> 
>>> I then try: "tc qdisc add dev eth0 root xcp capacity 10Mbit limit
>>> 500" and get: "Unknown qdisc "xcp", hence option "capacity" is
>>> unparsable"
>>> 
>>> So then I read the INSTALL further to find some sort of solution and
>>> it mentions: This again assumes "tc" version is 2.4.7.  If your "tc"
>>> is a different version, download the iproute2 source code, and edit
>>> Makefile to point "TC_INCLUDE" to "-I..../iproute2/include
>>> -I..../iproute2/tc"
>>> 
>>> So, i did that, and i recompiled the q_xcp.so: lanthanum-ini
>>> src-1.0.1 # make q_xcp.so cc -O2 -fPIC 
>>> -I/var/tmp/portage/iproute2-2.6.11.20050310-r1/work/iproute2-2.6.11/i
>>> nc lude/ 
>>> -I/var/tmp/portage/iproute2-2.6.11.20050310-r1/work/iproute2-2.6.11/t
>>> c_ include -o q_xcp.o -c q_xcp.c ld -shared -o q_xcp.so q_xcp.o rm -f 
>>> q_xcp.o
>>> 
>>> But i still get the same error.... so then my very final last effort 
>>> was to move q_xcp.c to my iproute2 source code tc/ directory and
>>> added this to the makefile: TCMODULES += q_xcp.o
>>> 
>>> Then I compiled tc, and i check tc to see if the xcp qdisc functions 
>>> were loaded: lanthanum-ini tc # nm tc | grep xcp 080531ec t
>>> xcp_parse_opt 080533e0 t xcp_print_opt 08053426 t xcp_print_xstats
>>> 08070cc0 D xcp_util
>>> 
>>> 
>>> And finally: lanthanum-ini tc # ./tc qdisc add dev ath0 root xcp 
>>> capacity 54Mbit limit 500 Unknown qdisc "xcp", hence option
>>> "capacity" is unparsable
>>> 
>>> 
>>> I have no clue :(  I figured that putting the .so into /usr/lib would
>>>  have been enough.  Sorry for the long e-mail, I hope someone can
>>> help, and thank you for your time even if you don't know the solution
>>> but read this :)
>>> 
>>> - George
>>> 
>> 
>> The .so needs to go in /usr/lib/tc (assuming you are running relatively
>>  recent version of iproute2 tools).
>> 
>> Read source to tc.c where it calls dlopen.
>> 
>> 
> 
> Still didn't seem to solve the problem :\
> 
> In my tc.c i have: snprintf(buf, sizeof(buf), "/usr/lib/tc/q_%s.so", str);
> 
> 
> Also: lanthanum-ini tc # ls /usr/lib/tc experimental.dist  normal.dist
> pareto.dist  paretonormal.dist  q_netem.so  q_xcp.so
> 
> And finally: lanthanum-ini tc # tc qdisc add dev ath0 root xcp capacity
> 54Mbit limit 500 Unknown qdisc "xcp", hence option "capacity" is
> unparsable
> 
> Maybe i should add debugging in tc.c and see if it sees the .so and fails
> to load it or something.
> 
> Any other suggestions?
> 
> Thanks for all the responses, George
> 
> _______________________________________________ LARTC mailing list 
> LARTC@mailman.ds9a.nl 
> http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
> 
> 


-- 

Re: Re: created new q_disc, inserted module, tc tells me unknown qdisc

[Tim Shepard]

> Maybe i should add debugging in tc.c and see if it sees the .so and fails to load it or something.

Yes.   I would do that next.

Compile tc with -g and then run it under gdb and step through that
part to see what happens.

			-Tim Shepard
			 shep@alum.mit.edu