[Vm-dev] VM Maker: VMMaker.oscog-eem.3142.mcz

Jaromir Matas mail at jaromir.net
Sun Jan 23 09:53:36 UTC 2022

Hi Eliot,

> Hi Jaromir,
> On Sat, Jan 22, 2022 at 3:57 AM Jaromir Matas <mail at jaromir.net> wrote:
> >
> >
> > Hi Eliot,
> >
> > I’d like to test it but the build failed for Windows and Mac; not sure
> > what it means…
> >
> > Sorry to hear the current “incorrect” suspend behavior has been exploited
> > more than expected in the existing code.
> >
> It's not the incorrect suspend behaviour that's being exploited, it's the
> return value of suspend.  Existing code appears to depend on the
> semaphore/mutex a process is blocked on being answered by suspend.

Yes, that's what I meant, actually :) I understand knowing the list was vital to e.g. recognize whether the process was blocked or runnable (#releaseCriticalSection).

> What would you think about having primitiveSuspendV2 return self instead of
> > any list at all – to make all state changing methods answer consistently
> > (like e.g. VW do)… if the answer expected by the “affected” code base has
> > to be provided by primitiveSuspend anyways.
> >
> I don't see this is at all useful.  If one isn't interested in the
> semaphore/mutex return value one does not have to examine it.  But there is
> no way of getting the list once the process has been removed from it other
> than by having the suspend primitive answer it.

Well yes, it surely is more useful to return something in addition to the powerful side effect :) I was just wondering if it's not a "temptation" to be better avoided. I suggested in another post the list is still available on the suspendedContext's stack should someone really want it. But I'm just inquiring here to satisfy my curiosity, sorry.

> So if one isn't interested in the return value simply write something of
> the form
>     aProcess suspend; yourself
> But if one *is* interested in the result then the primitive better
> answer it, nbo?

Oh, if there's a use case even with the new primitiveSuspendV2 then no doubt.

Thanks again for sharing your thoughts!



From: Vm-dev <vm-dev-bounces at lists.squeakfoundation.org> on behalf of Eliot Miranda <eliot.miranda at gmail.com>
Sent: Sunday, January 23, 2022 12:33:08 AM
To: Open Smalltalk Virtual Machine Development Discussion <vm-dev at lists.squeakfoundation.org>
Subject: Re: [Vm-dev] VM Maker: VMMaker.oscog-eem.3142.mcz

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/vm-dev/attachments/20220123/53ae2e2c/attachment.html>

More information about the Vm-dev mailing list