Re: [Libguestfs] [nbdkit PATCH 1/2] plugins: Add .thread_model callback
On 5/20/19 9:18 AM, Eric Blake wrote:
> (2) Shouldn't it be an error if the thread model returns a
more
> parallel thread model than the constant?
I thought about that, but my initial idea was to instead just declare
that attempts at a more parallel model are just silently ignored (with
at most a debug message visible during -fv).
I hit send too soon. My biggest reasoning for this? Consider the python
plugin. If we allow a python script to request PARALLEL now (but
silently ignore it, because our C glue code currently defines the
constant to SERIALIZE_ALL_REQUESTS), then that script will instantly
gain parallel support if a future nbdkit version manages to get the C
glue code rewritten to use better re-entrancy to the point of redefining
THREAD_MODEL to PARALLEL after all. (Based on code comments, it may be
doable with some effort for python, although I have less hopes for Ruby).
>
> Anyway patch series generally looks fine to me.
Thanks; I'll push shortly.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
Attachments:
- signature.asc (application/pgp-signature — 488 bytes)