Re: 2.4.19pre2aa1

[Andrew Morton]

Rik van Riel wrote:
> 
> On Wed, 13 Mar 2002, Andrea Arcangeli wrote:
> > On Wed, Mar 13, 2002 at 08:30:55AM +0100, Andrea Arcangeli wrote:
> > >  {
> > >     clear_bit(BH_Wait_IO, &bh->b_state);
> > >     clear_bit(BH_Lock, &bh->b_state);
> > > +   clear_bit(BH_Launder, &bh->b_state);
> > >     smp_mb__after_clear_bit();
> > >     if (waitqueue_active(&bh->b_wait))
> >
> > actually, while refining the patch and integrating it, I audited it some
> > more carefully and the above was wrong,
> 
> It's complex.
> 
> Would there be a way to simplify the thing so the author
> of the code can at least get it right and there's a chance
> of other people understanding it too ? ;)

I'll be documenting the BH state bits, and sync_page_buffers(),
when it settles down.

> ...
> <insert bitkeeper endorsement here>

You should lubricate it first.

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