Re: [PATCH 0/3] Fixes for vfs-scale and vfs-automount

[Ian Kent <raven@themaw.net>]

On Thu, 2011-02-24 at 03:14 +0000, Al Viro wrote:
> On Thu, Feb 24, 2011 at 11:03:38AM +0800, Ian Kent wrote:
> 
> > I also have a sick feeling that dentrys may become negative at any point
> > after __d_lookup_rcu() .....
> 
> Yes.  To get stability of ->d_inode (assuming the sucker isn't pinned down
> in normal way by ->d_count) you need ->d_lock.
> 
> > > Ho-hum...  I can reach RHTS, but I'd rather do that at home boxen, if
> > > possible...  Has it been reproduced on UP boxen with SMP kernels, BTW?
> > 
> > Nope, I'd need to build a kernel specifically for that. I'm not sure how
> > useful that would be though since the test is specifically meant to
> > expose problems with multiple concurrent processes accessing an
> > automount tree. I don't see any problem running the Connectathon tests
> > which is essentially one automount and one client process.
> 
> Heh...  No, it's just that the only SMP box I have locally right now
> is dual ultrasparc.  Anyway, I can live with RHTS.

If you want to get hold of the test I'm using checkout autofs-RHEL-5,
"cd autofs-tests/submount-test", "make rpm" and use the resulting
rh-tests-autofs-submount-test-1.0-15.noarch.rpm. There are some
beaker/rhts rpm dependencies. Let me know if it gets painful and I'll
try and work out what you need. The test isn't very flash but it does
stress autofs.

Ha, I haven't even turned on my Ultrsparc 2 in months, it's only got an
old version of Solaris on it now anyway, ;)