From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 2/2] [IPV4] route: Dynamic hash table sizing.
Date: Wed, 09 Aug 2006 04:14:52 -0700 (PDT)
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=46rom: Eric Dumazet <dada1@cosmosbay.com>
Date: Wed, 9 Aug 2006 12:09:28 +0200

> On Wednesday 09 August 2006 09:53, David Miller wrote:
>=20
> > +	if (atomic_read(&ipv4_dst_ops.entries) >=3D (hmask + 1) &&
> > +	    (hmask + 1) < ip_rt_hashsz_limit)
> > +		schedule_work(&rtcache_work);
> > +	return 0;
> >  }
> >
>=20
> I wonder if you should not replicate this test (against (hmask + 1) <=
=20
> ip_rt_hashsz_limit) in rtcache_resize() itself, because we might end =
calling=20
> rthash_new_size() while (hmask +1 ) =3D ip_rt_hashsz_limit

That's a good point, let me think about that.

> > -=A0=A0=A0=A0=A0=A0=A0mult =3D ((u64)ip_rt_gc_interval) << long_log=
2(hmask + 1);
> > +=A0=A0=A0=A0=A0=A0=A0mult =3D ((u64)(hmask + 1)) << (u64)ip_rt_gc_=
interval;
>=20
> Not sure I understand what you did here (in rt_check_expire()), could=
 you=20
> please explain the math ? (I may be wrong but (x * 2^y) !=3D (y * 2^x=
) for=20
> general values of x and y)

Indeed I'm a retard.

I made the same error in another location:

@@ -857,7 +984,7 @@ static int rt_garbage_collect(void)
=20
 	/* Calculate number of entries, which we want to expire now. */
 	goal =3D atomic_read(&ipv4_dst_ops.entries) -
-		(ip_rt_gc_elasticity << long_log2(hmask + 1));
+		((hmask + 1) << ip_rt_gc_elasticity);

I'll revert both of those changes, thanks.