[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v3 0/8] [RfC] fix tracing for modules
From: |
Daniel P . Berrangé |
Subject: |
Re: [PATCH v3 0/8] [RfC] fix tracing for modules |
Date: |
Mon, 29 Mar 2021 10:23:42 +0100 |
User-agent: |
Mutt/2.0.5 (2021-01-21) |
On Fri, Mar 26, 2021 at 01:47:00PM +0100, Gerd Hoffmann wrote:
> Hi,
>
> > eg a trace point "dma_map_wait" gets mapped to probes in many
> > .stp files, once per target, because we need to match based on
> > the executable path:
> >
> > probe qemu.system.x86_64.dma_map_wait =
> > process("/usr/libexec/qemu-system-x86_64").mark("dma_map_wait")
> > probe qemu.system.x86_64.dma_map_wait =
> > process("/usr/libexec/qemu-system-ppc64").mark("dma_map_wait")
>
> Probe qemu.system.ppc64.dma_map_wait = ...
>
> Can I trace qemu started from build directory?
> Seems scripts/qemu-trace-stap doesn't support that.
We should really generate extra equiv .stp files just for running from
the build.
> > qxl.destroy_primary(int qid) "%d"
> > qxl.enter_vga_mode(int qid) "%d"
> > qxl.exit_vga_mode(int qid) "%d"
> >
> > this would be backwards compatible, as we can turn the "." back into
> > a "_" for all existing trace backends, except stp.
>
> Hmm, not sure I like this inconsistency. I think names should be the
> same no matter which trace backend is used.
Regards,
Daniel
--
|: https://berrange.com -o- https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org -o- https://fstop138.berrange.com :|
|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|