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Date: Wed, 2 Apr 2003 17:30:20 -0500 (EST)
From: Jeff Roberson <jroberson@chesapeake.net>
To: Julian Elischer <julian@elischer.org>
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cc: Juli Mallett <jmallett@FreeBSD.org>
cc: Alexander Leidinger <Alexander@Leidinger.net>
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cc: Robert Watson <rwatson@FreeBSD.org>
cc: current@FreeBSD.org
Subject: Re: libthr and 1:1 threading.
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On Wed, 2 Apr 2003, Julian Elischer wrote:

>
>
> On Wed, 2 Apr 2003, Juli Mallett wrote:
>
> > * De: Jeff Roberson <jroberson@chesapeake.net> [ Data: 2003-04-02 ]
> > 	[ Subjecte: Re: libthr and 1:1 threading. ]
> > > On Wed, 2 Apr 2003, Terry Lambert wrote:
> > > > Also, any ETA on the per process signal mask handing bug in
> > > > libthr?  Might not be safe to convert everything up front, in
> > > > a rush of eager enthusiasm...
> > >
> > > Which bug is that?  I'm not aware of it.
> >
> > I think Terry is referring to the Uncertainty & Doubt as if it were
> > a bug over the lack of a process sigmask (moved into the threads),
> > as raised by the M:N group.
>
> I think this IS a problem. We need a per-process mask.
> to block signals that no thread is interested in.
> Since M:N threads do not have a kernel thread for each userland thread,
> there is nowhere to store this info any more.
>

Then set the mask to be the same on all threads in the process.  The mask
is set in swapcontext though so it seems reasonable to me that it is
atomically updated when you schedule a new user thread on a kse.

> I'd be happy to have it be a per-ksegrp mask actually..
> (to help deliver the signal to the right group to lower the interaction
> between UTS's in different groups.)
>