From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@davemloft.net>
Subject: Re: [6/6]: jenkins hash for neigh
Date: Sun, 3 Oct 2004 14:55:52 -0700
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To: Herbert Xu <herbert@gondor.apana.org.au>
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On Sat, 2 Oct 2004 17:50:51 +1000
Herbert Xu <herbert@gondor.apana.org.au> wrote:

> On Mon, Sep 27, 2004 at 11:15:20AM -0700, David S. Miller wrote:
> > On Mon, 27 Sep 2004 21:48:33 +1000
> > Herbert Xu <herbert@gondor.apana.org.au> wrote:
> > 
> > > > -	if (tbl->entries > (tbl->hash_mask + 1))
> > > > +	if (tbl->entries > (tbl->hash_mask + 1)) {
> > > > +		write_lock_bh(&tbl->lock);
> > > >  		neigh_hash_grow(tbl, (tbl->hash_mask + 1) << 1);
> > > > +		write_unlock_bh(&tbl->lock);
> > > > +	}
> > > 
> > > The locking should be outside the if block as otherwise you may grow
> > > unnecessarily or grow into the same size :)
> > 
> > I'm not going to do that, because then we're grabbing that lock
> > twice on every neigh create operation and I was trying hard
> > to avoid that overhead.
> 
> Actually, why don't we just move the expansion into the locked section?
> 
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Works for me, patch applied.

Thanks Herbert.