Re: RFC: Kill -ERESTART_RESTARTBLOCK.

[David Woodhouse <dwmw2@infradead.org>]

On Fri, 2005-11-25 at 16:24 +0100, Roman Zippel wrote:
> The arguments have to be saved somewhere, otherwise ERESTARTNOHAND 
> wouldn't work, so my basic idea would be to change ERESTART_RESTARTBLOCK 
> into ERESTARTNOHAND + some extra state.

That's true; it should probably work.

> > One simpler option which _might_ work for pselect(), ppoll() and
> > sigsuspend() is a TIF_RESTORE_SIGMASK flag which restores the original
> > signal mask on the way back to userspace but _after_ calling do_signal()
> > with the temporary mask.
> 
> Now I see the problem with the signal mask and I agree, this would be a 
> simpler and IMO preferable approach.

Yes; and its downside (-EINTR even when the signal gets ignored) is
avoided by the above -- or just by using -ERESTARTNOHAND, in fact.

I think I'll use this approach, and probably use -ERESTARTNOHAND in the
first instance. Because ppoll() is going to take a timespec instead of
just an integer for the timeout, we can write back to it as we do for
select, and there shouldn't be a problem restarting. 

Thanks.

-- 
dwmw2