Message-ID: <c5920cb1f3db053c705a988cf484bbbaa5c3dcfa.camel@microchip.com>
Subject: Re: [PATCH net-next 02/10] net: microchip: sparx5: Clear rule
 counter even if lookup is disabled
From:   Steen Hegelund <steen.hegelund@microchip.com>
To:     Dan Carpenter <error27@gmail.com>
CC:     "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        <UNGLinuxDriver@microchip.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Casper Andersson <casper.casan@gmail.com>,
        "Russell King" <rmk+kernel@armlinux.org.uk>,
        Wan Jiabing <wanjiabing@vivo.com>,
        "Nathan Huckleberry" <nhuck@google.com>,
        <linux-kernel@vger.kernel.org>, <netdev@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        "Daniel Machon" <daniel.machon@microchip.com>,
        Horatiu Vultur <horatiu.vultur@microchip.com>,
        Lars Povlsen <lars.povlsen@microchip.com>,
        Michael Walle <michael@walle.cc>
Date:   Mon, 13 Feb 2023 13:44:35 +0100
In-Reply-To: <Y+ofJK2psEnj9QNh@kadam>
References: <20230213092426.1331379-1-steen.hegelund@microchip.com>
         <20230213092426.1331379-3-steen.hegelund@microchip.com>
         <Y+ofJK2psEnj9QNh@kadam>
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Hi Dan,

On Mon, 2023-02-13 at 14:29 +0300, Dan Carpenter wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know th=
e
> content is safe
>=20
> On Mon, Feb 13, 2023 at 10:24:18AM +0100, Steen Hegelund wrote:
> > The rule counter must be cleared when creating a new rule, even if the =
VCAP
> > lookup is currently disabled.
> >=20
> > Signed-off-by: Steen Hegelund <steen.hegelund@microchip.com>
>=20
> Is this a bugfix?=C2=A0 If so what are the user visible effects of this b=
ug
> and please add a Fixes tag.=C2=A0 If not then could you explain more what
> this patch is for?

Yes this is a bugfix of a side effect introduced by my mid-January series "=
Add
support for two classes of VCAP rules" where this counter change should hav=
e
been added too.

The counter problem is only present on VCAP that has external counters, so =
it
only affects the IS2 and ES0 VCAP on Sparx5 and none of the LAN966x VCAPs.

I will add a Fixes tag to the next series.

>=20
> > ---
> > =C2=A0drivers/net/ethernet/microchip/vcap/vcap_api.c=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0 | 7 +++++--
> > =C2=A0drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c | 4 ++--
> > =C2=A02 files changed, 7 insertions(+), 4 deletions(-)
> >=20
> > diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > b/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > index 6307d59f23da..68e04d47f6fd 100644
> > --- a/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > +++ b/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > @@ -2246,6 +2246,11 @@ int vcap_add_rule(struct vcap_rule *rule)
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (move.count > 0)
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 vcap_move_rules(ri, &move);
> >=20
> > +=C2=A0=C2=A0=C2=A0=C2=A0 /* Set the counter to zero */
> > +=C2=A0=C2=A0=C2=A0=C2=A0 ret =3D vcap_write_counter(ri, &ctr);
> > +=C2=A0=C2=A0=C2=A0=C2=A0 if (ret)
> > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 goto out;
> > +
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (ri->state =3D=3D VCAP_RS_DISABLED) {
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 /* Erase the rule area */
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 ri->vctrl->ops->init(ri->ndev, ri->admin, ri->addr, ri->size);
> > @@ -2264,8 +2269,6 @@ int vcap_add_rule(struct vcap_rule *rule)
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 pr_err("%s:%d: rule write error: %d\n", __func__, __LINE__,
> > ret);
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 goto out;
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 }
> > -=C2=A0=C2=A0=C2=A0=C2=A0 /* Set the counter to zero */
> > -=C2=A0=C2=A0=C2=A0=C2=A0 ret =3D vcap_write_counter(ri, &ctr);
> > =C2=A0out:
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 mutex_unlock(&ri->admin->lock);
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 return ret;
> > diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> > b/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> > index b2753aac8ad2..0a1d4d740567 100644
> > --- a/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> > +++ b/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> > @@ -1337,8 +1337,8 @@ static void vcap_api_encode_rule_test(struct kuni=
t
> > *test)
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 u32 port_mask_rng_mask =3D 0x0f;
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 u32 igr_port_mask_value =3D 0xffabcd01;
> > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 u32 igr_port_mask_mask =3D ~0;
> > -=C2=A0=C2=A0=C2=A0=C2=A0 /* counter is written as the last operation *=
/
> > -=C2=A0=C2=A0=C2=A0=C2=A0 u32 expwriteaddr[] =3D {792, 793, 794, 795, 7=
96, 797, 792};
> > +=C2=A0=C2=A0=C2=A0=C2=A0 /* counter is written as the first operation =
*/
> > +=C2=A0=C2=A0=C2=A0=C2=A0 u32 expwriteaddr[] =3D {792, 792, 793, 794, 7=
95, 796, 797};
>=20
> So this moves 792 from the last to the first.=C2=A0 I would have expected
> that that would mean that we had to do something like this as well:
>=20
> diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> b/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> index b2753aac8ad2..4d36fad0acab 100644
> --- a/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> +++ b/drivers/net/ethernet/microchip/vcap/vcap_api_kunit.c
> @@ -1400,7 +1400,7 @@ static void vcap_api_encode_rule_test(struct kunit
> *test)
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /* Add rule with write callbac=
k */
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ret =3D vcap_add_rule(rule);
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 KUNIT_EXPECT_EQ(test, 0, ret);
> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 KUNIT_EXPECT_EQ(test, 792, is2_admi=
n.last_used_addr);
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 KUNIT_EXPECT_EQ(test, 797, is2_admi=
n.last_used_addr);
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 for (idx =3D 0; idx < ARRAY_SI=
ZE(expwriteaddr); ++idx)
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0 KUNIT_EXPECT_EQ(test, expwriteaddr[idx],
> test_updateaddr[idx]);
>=20
>=20
> But I couldn't really figure out how the .last_used_addr stuff works.
> And presumably fixing this unit test is the point of the patch...

It is just the array of addresses written to in the order that they are wri=
tten,
so for the visibility I would like to keep it as an array.

>=20
> regards,
> dan carpenter

Thanks for the comments!

BR
Steen