Re: [Qemu-devel] [PATCH 00/13] instrument: Add basic event instrumentation

[Peter Maydell]

On 1 August 2017 at 14:48, Stefan Hajnoczi <address@hidden> wrote:
> Thanks for sharing the requirements.  A stable API is necessary for
> providing these features.
>
> We're essentially talking about libqemu.  That means QEMU in library
> form with an API for JIT engine, reverse engineering, instrumentation,
> etc tasks.

> Maintaining libqemu will take ongoing effort and no one has committed.
> The last discussion about libqemu was here:
> https://lists.gnu.org/archive/html/qemu-devel/2016-11/msg04847.html

That thread seems to be focused on trying to extract TCG
from the rest of QEMU, which definitely isn't a requirement
for instrumentation, and I would suggest is something
of a distraction from it. I want to be able to say "just
instrument this setup that QEMU already provides as a
board model", not have to write a driver that duplicates
all the work vl.c and our board models do for us today,
and I don't need the TCG engine to be a library to do that...

I agree that we want to provide something that is at least
closer to a stable API than "just expose trace events",
though.

thanks
-- PMM