On Fri, 6 Mar 2020 15:13:56 -0500 Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > On Fri, 6 Mar 2020 11:29:00 +0200 > "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@xxxxxxxxx> wrote: > > > From: "Tzvetomir (VMware) Stoyanov" <tz.stoyanov@xxxxxxxxx> > > > > The tracefs library provides APIs for accessing files from tracefs. > > The library is part of trace-cmd, it is installed as part of trace-cmd > > installation. KernelShark uses some of those APIs and must be linked with > > the library > > > > Tzvetomir (VMware) Stoyanov (2): > > KernelShark2.0: Link KernelShark to libtracefs > > KernelShark2.0: Use libtracefs APIs to access tracefs > > > > I added these patches to the latest kernelshark-2.0 and it still doesn't > work for me. I did a little debugging, and noticed that it fails while > reading the guest trace.dat file with: > > plugin "kvm_combo" failed to initialize on stream /tmp/trace-host-Fedora21. > > It seems to require that the guest trace.dat file has kvm events? > > Note, as I build my guest kernel with a make localmodconfig, which disables > all modules that are not necessary to boot the box, there is no kvm events > there. I can see why the host may need them, but not the guest. I'll > rebuild my guest kernel with kvm events and see if that solves this (but > that shouldn't be the case). > Just confirmed it. If I add kvm events to the guest, it synchronizes automatically. Thus, it's a bug to expect the guest to have kvm events, as there's no reason for them to do so. -- Steve
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