cvs commit: src/sys/dev/streams streams.csrc/sys/kernkern_descrip.csrc/sys/opencrypto cryptodev.c

[Scott Long]

On Mon, 20 Oct 2003, Scott Long wrote:
>
>
> On Mon, 20 Oct 2003, Scott Long wrote:
>
> > On Mon, 20 Oct 2003, David Malone wrote:
> > > > > This reminds me that we still hold Giant around pipe(2) because it isn't
> > > > > declared MPSAFE in the syscall table.  Is this still necessary?
> > >
> > > > I've been suspicious of this too, and I was hoping that you would have
> > > > an answer.  Can we go ahead and correct this?
> > >
> > > I think we may need to check the calling of pipeclose() in pipe(),
> > > but as this is only done in an error case, it is probably safe enough
> > > to just grab Giant for that. (The mac_* calls may need to be checked
> > > too).
> >
> > pipeclose() seems to have some concept of locking, though I don't know
> > what the implications are of it saying, 'gee, the mutex on this pipe was
> > never initialized, so I just won't worry about locking.'  Towards the
> > end of pipeclose() Giant is acquired, though that action is likely no
> > longer needed either.
>
> Nix that last part, I was looking at a stale file.  pipeclose() does not
> explicitely grab Gaint.
>
> Scott
>
>

I've run several buildworlds while doing background pipe tests, all
without any problems with WITNESS and INVARIANTS enabled on a fast SMP
machine.  I can't report any performance change since I'm only testing
correctness now, but it looks promising.  I'd advise to go ahead and
throw the switch on this.

Scott