Hi, On Wed, Nov 22, 2017 at 06:39:11PM +0100, Robin Michielsen wrote: > Hi all, > >Any suggestions from anyone on what to check and/or how to debug the issue >that I described in my mail from last week?
From lttng-sessiond.log: lttng-ring-buffer-client-discard is already loaded Error: Unable to load required module lttng-ring-buffer-client-discard Is there any particular reason why some modules are already loaded ? Did you perform a "depmod -a" on the target? Cheers > > Kind regards, > Robin > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Jérémie Galarneau > Sent: Tuesday, 14 November, 2017 22:14 > To: Robin Michielsen > Cc: [email protected] > Subject: Re: [lttng-dev] Error: opening metadata failed (LTTng on OpenWRT) > > On 14 November 2017 at 12:09, Robin Michielsen <[email protected]> > wrote: > > Hi Jérémie, > > > > Maybe I misunderstood how to create a session, but are the commands that I > > listed not sufficient for this? > > > > • lttng create > > • lttng enable-event --kernel --syscall open,close > > • lttng start > > > > Yes, sorry. I missed it on the first read through. > > Jérémie > > > Kind regards, > > Robin > > > > -----Original Message----- > > From: [email protected] [mailto:[email protected]] > > On Behalf Of Jérémie Galarneau > > Sent: Tuesday, 14 November, 2017 17:09 > > To: Robin Michielsen > > Cc: [email protected] > > Subject: Re: [lttng-dev] Error: opening metadata failed (LTTng on > > OpenWRT) > > > > Hi Robin, > > > > Can you add the commands you use to create the session? > > > > Thanks, > > Jérémie > > > > On 14 November 2017 at 04:41, Robin Michielsen > > <[email protected]> wrote: > >> Hi all, > >> > >> > >> > >> I am trying to trace the Linux kernel (system calls) using LTTng on a > >> platform that is running OpenWRT. I have cross compiled the latest > >> versions > >> (2.10.x) of the lttng-modules, lttng-tools and lttng-ust packages and > >> installed these on my OpenWRT system. Now when I start a kernel trace > >> then the lttng tool returns the error "LTTng transport relay-metadata > >> not found / > >> Error: Opening metadata failed". Does anybody know what might cause > >> this error, or have a hint on what to check? > >> > >> > >> > >> I have attached the captured output of ‘lttng-sessiond -vvv > >> --verbose-consumer’. Here is some more context: > >> > >> · MIPS platform running Linux 3.18.29 > >> > >> · Package versions: > >> > >> o lttng-modules-2.10.4 > >> > >> o lttng-tools-2.10.1 > >> > >> o lttng-ust-2.10.0 > >> > >> · lsmod shows that the following modules have been loaded: > >> > >> o lttng_clock > >> > >> o lttng_lib_ring_buffer > >> > >> o lttng_ring_buffer_client_discard > >> > >> o lttng_statedump > >> > >> o lttng_tracer > >> > >> · Commands to create and start a session: > >> > >> o lttng create > >> > >> o lttng enable-event --kernel --syscall open,close > >> > >> o lttng start > >> > >> > >> > >> When ‘lttng start’ is called then lttng-sessiond’s debug output shows > >> “Closing metadata fd -1 (in trace_kernel_destroy_metadata() at > >> trace-kernel.c:569)” followed by “Sending response (size: 20, retcode: > >> Opening metadata failed (45)) (in thread_manage_clients() at main.c:4641)”. > >> I assume that the error that I’m seeing is because for some reason > >> metadata fd is being closed. > >> > >> > >> > >> Does anybody know what may cause this issue, or have a hint on to check? > >> > >> > >> > >> Kind regards, > >> > >> Robin > >> > >> > >> > >> > >> _______________________________________________ > >> lttng-dev mailing list > >> [email protected] > >> https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev > >> > > > > > > > > -- > > Jérémie Galarneau > > EfficiOS Inc. > > http://www.efficios.com > > > > > > -- > Jérémie Galarneau > EfficiOS Inc. > http://www.efficios.com > > _______________________________________________ > lttng-dev mailing list > [email protected] > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev -- Jonathan Rajotte-Julien EfficiOS _______________________________________________ lttng-dev mailing list [email protected] https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
