* [email protected] ([email protected]) wrote: > Mathieu: > > Looks good! I went through my menuconfig and enabled all of these. > > One suggestion -- change 'requied' to 'required' in the line 'Kernel > config options requied'
Done. Thanks ! Mathieu > > Thank you, > > Ryan Kyser > > > > > From: > Mathieu Desnoyers <[email protected]> > To: > [email protected] > Cc: > [email protected], David Goulet <[email protected]> > Date: > 04/06/2012 12:31 PM > Subject: > Re: [lttng-dev] lttng create --output problem > > > > * Mathieu Desnoyers ([email protected]) wrote: > > * [email protected] ([email protected]) wrote: > > > *** I'm resending this because I saw that mailman scrubbed my > message.*** > > > > > > > > > Mathieu: > > > > > > I have provided the requested information below. > > > > > > Also, I want to include some additional information which may (or may > not) > > > be part of the problem. When lttng-sessiond starts, I'm met with a > > > modprobe error (see below). It looks as if this module is not being > built > > > at compile time because CONFIG_KVM is not enabled. However, if I go > into > > > the kernel menuconfig and search for KVM, no results are returned. > > > > Normally lttng-modules should use the features that are there without > > complaining too much. > > > > What I notice is that you don't have CONFIG_HAVE_SYSCALL_TRACEPOINTS > > enabled. So -k -a is enabling both tracepoints and syscalls, and given > > that syscall enabling returns ENOSYS, it prints this error and bails > > out. > > > > The correct behavior would be to only fail of _both_ tracepoint and > > syscall instrumentation fail to enable. > > > > Short term solution for you would be to enable > > CONFIG_HAVE_SYSCALL_TRACEPOINTS in your kernel. > > FYI, here is the update. Feedback is welcome, > > commit d0a5ff7d8479de94f1082055d1d940d660027fc8 > Author: Mathieu Desnoyers <[email protected]> > Date: Fri Apr 6 12:32:22 2012 -0400 > > Fix: document required and optional kernel config options in README > > Signed-off-by: Mathieu Desnoyers <[email protected]> > > diff --git a/README b/README > index abbfd27..ac0dc88 100644 > --- a/README > +++ b/README > @@ -1,7 +1,7 @@ > LTTng 2.0 modules > > Mathieu Desnoyers > -February 8, 2012 > +April 6, 2012 > > LTTng 2.0 kernel modules build against a vanilla or distribution kernel, > without > need for additional patches. Other features: > @@ -48,9 +48,42 @@ LTTng 0.x patchset, but the lttng-modules 2.0 replace > the lttng-modules > 0.x, so both tracers cannot be installed at the same time for a given > kernel version. > > -LTTng-modules depends on having kallsyms enabled in the kernel it is > -built against. Ideally, if you want to have system call tracing, the > -"Trace Syscalls" feature should be enabled too. > + > +* Kernel config options requied > + > +CONFIG_KALLSYMS: required > + * See wrapper/ files. This is necessary until the few required missing > + symbols are exported to GPL modules from mainline. > +CONFIG_HIGH_RES_TIMERS: required > + * Needed for LTTng 2.0 clock source. > +CONFIG_TRACEPOINTS: required > + kernel tracepoint instrumentation > + * Enabled as side-effect of any of the perf/ftrace/blktrace > + instrumentation features. > + > + > +* Kernel config options supported (optional) > + > +The following kernel configuration options will affect the features > +available from LTTng: > + > + > +CONFIG_HAVE_SYSCALL_TRACEPOINTS: > + system call tracing > + lttng enable-event -k --syscall > + lttng enable-event -k -a > +CONFIG_PERF_EVENTS: > + performance counters > + lttng add-context -t perf:* > +CONFIG_EVENT_TRACING: > + needed to allow block layer tracing > +CONFIG_KPROBES: > + Dynamic probe. > + lttng enable-event -k --probe ... > +CONFIG_KRETPROBES: > + Dynamic function entry/return probe. > + lttng enable-event -k --function ... > + > > * Note about Perf PMU counters support > > > -- > Mathieu Desnoyers > Operating System Efficiency R&D Consultant > EfficiOS Inc. > http://www.efficios.com > > > -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
