Commit 009d30f1 authored by Vladimir Oltean's avatar Vladimir Oltean Committed by Jakub Kicinski
Browse files

net: mscc: ocelot: extend ocelot->fwd_domain_lock to cover ocelot->tas_lock 



In a future commit we will have to call vsc9959_tas_guard_bands_update()
from ocelot_port_update_active_preemptible_tcs(), and that will be
impossible due to the AB/BA locking dependencies between
ocelot->tas_lock and ocelot->fwd_domain_lock.

Just like we did in commit 3ff468ef ("net: mscc: ocelot: remove
struct ocelot_mm_state :: lock"), the only solution is to expand the
scope of ocelot->fwd_domain_lock for it to also serialize changes made
to the Time-Aware Shaper, because those will have to result in a
recalculation of cut-through TCs, which is something that depends on the
forwarding domain.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Message-ID: <20230705104422.49025-2-vladimir.oltean@nxp.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent ceb20a3c

drivers/net/dsa/ocelot/felix.c

+2 −2
Original line number Diff line number Diff line
@@ -1790,12 +1790,12 @@ static int felix_change_mtu(struct dsa_switch *ds, int port, int new_mtu) 


	ocelot_port_set_maxlen(ocelot, port, new_mtu);



	mutex_lock(&ocelot->tas_lock);

	mutex_lock(&ocelot->fwd_domain_lock);



	if (ocelot_port->taprio && felix->info->tas_guard_bands_update)

		felix->info->tas_guard_bands_update(ocelot, port);



	mutex_unlock(&ocelot->tas_lock);

	mutex_unlock(&ocelot->fwd_domain_lock);



	return 0;

}

drivers/net/dsa/ocelot/felix_vsc9959.c

+22 −14
Original line number Diff line number Diff line
@@ -1217,7 +1217,7 @@ static void vsc9959_tas_guard_bands_update(struct ocelot *ocelot, int port) 
	u8 tas_speed;

	int tc;



	lockdep_assert_held(&ocelot->tas_lock);

	lockdep_assert_held(&ocelot->fwd_domain_lock);



	taprio = ocelot_port->taprio;
@@ -1259,8 +1259,6 @@ static void vsc9959_tas_guard_bands_update(struct ocelot *ocelot, int port) 


	vsc9959_tas_min_gate_lengths(taprio, min_gate_len);



	mutex_lock(&ocelot->fwd_domain_lock);



	for (tc = 0; tc < OCELOT_NUM_TC; tc++) {

		u32 requested_max_sdu = vsc9959_tas_tc_max_sdu(taprio, tc);

		u64 remaining_gate_len_ps;
@@ -1323,8 +1321,6 @@ static void vsc9959_tas_guard_bands_update(struct ocelot *ocelot, int port) 
	ocelot_write_rix(ocelot, maxlen, QSYS_PORT_MAX_SDU, port);



	ocelot->ops->cut_through_fwd(ocelot);



	mutex_unlock(&ocelot->fwd_domain_lock);

}



static void vsc9959_sched_speed_set(struct ocelot *ocelot, int port,
@@ -1351,7 +1347,7 @@ static void vsc9959_sched_speed_set(struct ocelot *ocelot, int port, 
		break;

	}



	mutex_lock(&ocelot->tas_lock);

	mutex_lock(&ocelot->fwd_domain_lock);



	ocelot_rmw_rix(ocelot,

		       QSYS_TAG_CONFIG_LINK_SPEED(tas_speed),
@@ -1361,7 +1357,7 @@ static void vsc9959_sched_speed_set(struct ocelot *ocelot, int port, 
	if (ocelot_port->taprio)

		vsc9959_tas_guard_bands_update(ocelot, port);



	mutex_unlock(&ocelot->tas_lock);

	mutex_unlock(&ocelot->fwd_domain_lock);

}



static void vsc9959_new_base_time(struct ocelot *ocelot, ktime_t base_time,
@@ -1409,7 +1405,7 @@ static int vsc9959_qos_port_tas_set(struct ocelot *ocelot, int port, 
	int ret, i;

	u32 val;



	mutex_lock(&ocelot->tas_lock);

	mutex_lock(&ocelot->fwd_domain_lock);



	if (taprio->cmd == TAPRIO_CMD_DESTROY) {

		ocelot_port_mqprio(ocelot, port, &taprio->mqprio);
@@ -1421,7 +1417,7 @@ static int vsc9959_qos_port_tas_set(struct ocelot *ocelot, int port, 


		vsc9959_tas_guard_bands_update(ocelot, port);



		mutex_unlock(&ocelot->tas_lock);

		mutex_unlock(&ocelot->fwd_domain_lock);

		return 0;

	} else if (taprio->cmd != TAPRIO_CMD_REPLACE) {

		ret = -EOPNOTSUPP;
@@ -1504,7 +1500,7 @@ static int vsc9959_qos_port_tas_set(struct ocelot *ocelot, int port, 
	ocelot_port->taprio = taprio_offload_get(taprio);

	vsc9959_tas_guard_bands_update(ocelot, port);



	mutex_unlock(&ocelot->tas_lock);

	mutex_unlock(&ocelot->fwd_domain_lock);



	return 0;
@@ -1512,7 +1508,7 @@ static int vsc9959_qos_port_tas_set(struct ocelot *ocelot, int port, 
	taprio->mqprio.qopt.num_tc = 0;

	ocelot_port_mqprio(ocelot, port, &taprio->mqprio);

err_unlock:

	mutex_unlock(&ocelot->tas_lock);

	mutex_unlock(&ocelot->fwd_domain_lock);



	return ret;

}
@@ -1525,7 +1521,7 @@ static void vsc9959_tas_clock_adjust(struct ocelot *ocelot) 
	int port;

	u32 val;



	mutex_lock(&ocelot->tas_lock);

	mutex_lock(&ocelot->fwd_domain_lock);



	for (port = 0; port < ocelot->num_phys_ports; port++) {

		ocelot_port = ocelot->ports[port];
@@ -1563,7 +1559,7 @@ static void vsc9959_tas_clock_adjust(struct ocelot *ocelot) 
			       QSYS_TAG_CONFIG_ENABLE,

			       QSYS_TAG_CONFIG, port);

	}

	mutex_unlock(&ocelot->tas_lock);

	mutex_unlock(&ocelot->fwd_domain_lock);

}



static int vsc9959_qos_port_cbs_set(struct dsa_switch *ds, int port,
@@ -1634,6 +1630,18 @@ static int vsc9959_qos_query_caps(struct tc_query_caps_base *base) 
	}

}



static int vsc9959_qos_port_mqprio(struct ocelot *ocelot, int port,

				   struct tc_mqprio_qopt_offload *mqprio)

{

	int ret;



	mutex_lock(&ocelot->fwd_domain_lock);

	ret = ocelot_port_mqprio(ocelot, port, mqprio);

	mutex_unlock(&ocelot->fwd_domain_lock);



	return ret;

}



static int vsc9959_port_setup_tc(struct dsa_switch *ds, int port,

				 enum tc_setup_type type,

				 void *type_data)
@@ -1646,7 +1654,7 @@ static int vsc9959_port_setup_tc(struct dsa_switch *ds, int port, 
	case TC_SETUP_QDISC_TAPRIO:

		return vsc9959_qos_port_tas_set(ocelot, port, type_data);

	case TC_SETUP_QDISC_MQPRIO:

		return ocelot_port_mqprio(ocelot, port, type_data);

		return vsc9959_qos_port_mqprio(ocelot, port, type_data);

	case TC_SETUP_QDISC_CBS:

		return vsc9959_qos_port_cbs_set(ds, port, type_data);

	default:

drivers/net/ethernet/mscc/ocelot.c

+0 −1
Original line number Diff line number Diff line
@@ -2927,7 +2927,6 @@ int ocelot_init(struct ocelot *ocelot) 


	mutex_init(&ocelot->mact_lock);

	mutex_init(&ocelot->fwd_domain_lock);

	mutex_init(&ocelot->tas_lock);

	spin_lock_init(&ocelot->ptp_clock_lock);

	spin_lock_init(&ocelot->ts_id_lock);

drivers/net/ethernet/mscc/ocelot_mm.c

+2 −5
Original line number Diff line number Diff line
@@ -89,17 +89,14 @@ void ocelot_port_change_fp(struct ocelot *ocelot, int port, 
{

	struct ocelot_mm_state *mm = &ocelot->mm[port];



	mutex_lock(&ocelot->fwd_domain_lock);

	lockdep_assert_held(&ocelot->fwd_domain_lock);



	if (mm->preemptible_tcs == preemptible_tcs)

		goto out_unlock;

		return;



	mm->preemptible_tcs = preemptible_tcs;



	ocelot_port_update_active_preemptible_tcs(ocelot, port);



out_unlock:

	mutex_unlock(&ocelot->fwd_domain_lock);

}



static void ocelot_mm_update_port_status(struct ocelot *ocelot, int port)

include/soc/mscc/ocelot.h

+4 −4
Original line number Diff line number Diff line
@@ -863,12 +863,12 @@ struct ocelot { 
	struct mutex			stat_view_lock;

	/* Lock for serializing access to the MAC table */

	struct mutex			mact_lock;

	/* Lock for serializing forwarding domain changes */

	/* Lock for serializing forwarding domain changes, including the

	 * configuration of the Time-Aware Shaper, MAC Merge layer and

	 * cut-through forwarding, on which it depends

	 */

	struct mutex			fwd_domain_lock;



	/* Lock for serializing Time-Aware Shaper changes */

	struct mutex			tas_lock;



	struct workqueue_struct		*owq;



	u8				ptp:1;