libthr and 1:1 threading.

[Daniel Eischen]

On Wed, 2 Apr 2003, Jeff Roberson wrote:
> On Wed, 2 Apr 2003, Julian Elischer wrote:
> 
> >
> >
> > On Wed, 2 Apr 2003, Juli Mallett wrote:
> >
> > > * De: Jeff Roberson <jroberson at 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.

Jeff, are you _listening_ to us?  We've said multiple times
that the UTS does not enter the kernel when performing thread
switches.  The UTS does NOT use setcontext(), getcontext(),
or swapcontext().

-- 
Dan Eischen