Re: vfsmount lock issues on very large ppc64 box

[Tim Chen]

On Sat, 2011-07-16 at 19:04 -0600, Matthew Wilcox wrote:
> On Sun, Jul 17, 2011 at 10:50:27AM +1000, Anton Blanchard wrote:
> > Looking closer, all of these calls are in pipefs and sockfs.
> > Since we never mount either filesystem they never get a long term
> > reference and we always end up in the very slow write brlock path
> > that takes a lock for each online CPU.
> > 
> > Here is a quick hack that takes a long term reference on pipefs
> > and sockfs which fixes the problem. Any thoughts on how we should
> > fix it properly?
> 
> I know Tim and Andi have been looking into this ... I forget what their
> fix was though.
> 

I've sent out a trial patch a while ago on this problem, but didn't get
a response back. Nick or Al, can you take another look at this patch now
that other folks are also running into this issue?

http://marc.info/?l=linux-fsdevel&m=130273200502778&w=2

Thanks.

Tim

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/