Re: [patch 00/35] Jeff's ReiserFS Patch Queue

[Frederic Weisbecker <fweisbec@gmail.com>]

On Wed, Apr 01, 2009 at 06:34:07PM +0200, Ingo Molnar wrote:
> 
> * Jeff Mahoney <jeffm@suse.com> wrote:
> 
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> > Ingo Molnar wrote:
> > > * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> > > 
> > >>> Once this is applied, I expect reiserfs to be in deep 
> > >>> maintenance-only mode.
> > >> Heh, I hadn't expected even this.
> > > 
> > > Note, there are BKL-removal patches in the works by Frédéric 
> > > Weisbecker, for the tip:kill-the-BKL topic branch.
> > > 
> > > Reiser3 is the heaviest (and most non-trivial) BKL user amongst all 
> > > the filesystems, its BKL use is recursive and it frequently relies 
> > > on the implicit dropping of the BKL at various blocking points both 
> > > for correctness and for performance reasons.
> > > 
> > > There might be something worth posting+reviewing soon.
> > 
> > Oh interesting. I'm glad someone is working on this. I've started 
> > to several times and decided to focus my efforts on things outside 
> > of reiserfs instead. The reiserfs usage of the BKL has always been 
> > a black mark.
> 
> I'll let Frederic describe it but AFAIK the patch is working fine 
> with the BKL as a mutex and no lockdep complaints or lockups. The 
> main focus is now on finding the performance affecting spots, 
> because Frederic's main desktop is on reiserfs and he does not 
> accept a slowdown :)



Hehe :-)
No actually I would accept a tiny slowdown but I fear that the common
reiserfs users wouldn't.

I'm still working on this and once it's ready enough for an RFC patch,
I'll explain how is done the conversion to a mutex.

Stay tuned.

 
> 	Ingo