diff mbox series

[v2,net-next,11/15] net: enetc: act upon the requested mqprio queue configuration

Message ID 20230126125308.1199404-12-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series ENETC mqprio/taprio cleanup | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next, async
netdev/apply fail Patch does not apply to net-next

Commit Message

Vladimir Oltean Jan. 26, 2023, 12:53 p.m. UTC
Regardless of the requested queue count per traffic class, the enetc
driver allocates a number of TX rings equal to the number of TCs, and
hardcodes a queue configuration of "1@0 1@1 ... 1@max-tc". Other
configurations are silently ignored and treated the same.

Improve that by allowing what the user requests to be actually
fulfilled. This allows more than one TX ring per traffic class.
For example:

$ tc qdisc add dev eno0 root handle 1: mqprio num_tc 4 \
	map 0 0 1 1 2 2 3 3 queues 2@0 2@2 2@4 2@6
[  146.267648] fsl_enetc 0000:00:00.0 eno0: TX ring 0 prio 0
[  146.273451] fsl_enetc 0000:00:00.0 eno0: TX ring 1 prio 0
[  146.283280] fsl_enetc 0000:00:00.0 eno0: TX ring 2 prio 1
[  146.293987] fsl_enetc 0000:00:00.0 eno0: TX ring 3 prio 1
[  146.300467] fsl_enetc 0000:00:00.0 eno0: TX ring 4 prio 2
[  146.306866] fsl_enetc 0000:00:00.0 eno0: TX ring 5 prio 2
[  146.313261] fsl_enetc 0000:00:00.0 eno0: TX ring 6 prio 3
[  146.319622] fsl_enetc 0000:00:00.0 eno0: TX ring 7 prio 3
$ tc qdisc del dev eno0 root
[  178.238418] fsl_enetc 0000:00:00.0 eno0: TX ring 0 prio 0
[  178.244369] fsl_enetc 0000:00:00.0 eno0: TX ring 1 prio 0
[  178.251486] fsl_enetc 0000:00:00.0 eno0: TX ring 2 prio 0
[  178.258006] fsl_enetc 0000:00:00.0 eno0: TX ring 3 prio 0
[  178.265038] fsl_enetc 0000:00:00.0 eno0: TX ring 4 prio 0
[  178.271557] fsl_enetc 0000:00:00.0 eno0: TX ring 5 prio 0
[  178.277910] fsl_enetc 0000:00:00.0 eno0: TX ring 6 prio 0
[  178.284281] fsl_enetc 0000:00:00.0 eno0: TX ring 7 prio 0
$ tc qdisc add dev eno0 root handle 1: mqprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 1
[  186.113162] fsl_enetc 0000:00:00.0 eno0: TX ring 0 prio 0
[  186.118764] fsl_enetc 0000:00:00.0 eno0: TX ring 1 prio 1
[  186.124374] fsl_enetc 0000:00:00.0 eno0: TX ring 2 prio 2
[  186.130765] fsl_enetc 0000:00:00.0 eno0: TX ring 3 prio 3
[  186.136404] fsl_enetc 0000:00:00.0 eno0: TX ring 4 prio 4
[  186.142049] fsl_enetc 0000:00:00.0 eno0: TX ring 5 prio 5
[  186.147674] fsl_enetc 0000:00:00.0 eno0: TX ring 6 prio 6
[  186.153305] fsl_enetc 0000:00:00.0 eno0: TX ring 7 prio 7

The driver used to set TC_MQPRIO_HW_OFFLOAD_TCS, near which there is
this comment in the UAPI header:

        TC_MQPRIO_HW_OFFLOAD_TCS,       /* offload TCs, no queue counts */

but I'm not sure who even looks at this field. Anyway, since this is
basically what enetc was doing up until now (and no longer is; we
offload queue counts too), remove that assignment.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
v1->v2: move the mqprio teardown to enetc_reset_tc_mqprio(), and also
        call it on the error path

 drivers/net/ethernet/freescale/enetc/enetc.c | 102 +++++++++++++------
 1 file changed, 71 insertions(+), 31 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index e4718b50cf31..2d87deec6e77 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -2609,56 +2609,96 @@  static int enetc_reconfigure(struct enetc_ndev_priv *priv, bool extended,
 	return err;
 }
 
-int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data)
+static void enetc_debug_tx_ring_prios(struct enetc_ndev_priv *priv)
+{
+	int i;
+
+	for (i = 0; i < priv->num_tx_rings; i++)
+		netdev_dbg(priv->ndev, "TX ring %d prio %d\n", i,
+			   priv->tx_ring[i]->prio);
+}
+
+static void enetc_reset_tc_mqprio(struct net_device *ndev)
 {
 	struct enetc_ndev_priv *priv = netdev_priv(ndev);
-	struct tc_mqprio_qopt *mqprio = type_data;
 	struct enetc_hw *hw = &priv->si->hw;
 	struct enetc_bdr *tx_ring;
 	int num_stack_tx_queues;
-	u8 num_tc;
 	int i;
 
 	num_stack_tx_queues = enetc_num_stack_tx_queues(priv);
-	mqprio->hw = TC_MQPRIO_HW_OFFLOAD_TCS;
-	num_tc = mqprio->num_tc;
 
-	if (!num_tc) {
-		netdev_reset_tc(ndev);
-		netif_set_real_num_tx_queues(ndev, num_stack_tx_queues);
-		priv->min_num_stack_tx_queues = num_possible_cpus();
-
-		/* Reset all ring priorities to 0 */
-		for (i = 0; i < priv->num_tx_rings; i++) {
-			tx_ring = priv->tx_ring[i];
-			tx_ring->prio = 0;
-			enetc_set_bdr_prio(hw, tx_ring->index, tx_ring->prio);
-		}
+	netdev_reset_tc(ndev);
+	netif_set_real_num_tx_queues(ndev, num_stack_tx_queues);
+	priv->min_num_stack_tx_queues = num_possible_cpus();
+
+	/* Reset all ring priorities to 0 */
+	for (i = 0; i < priv->num_tx_rings; i++) {
+		tx_ring = priv->tx_ring[i];
+		tx_ring->prio = 0;
+		enetc_set_bdr_prio(hw, tx_ring->index, tx_ring->prio);
+	}
+
+	enetc_debug_tx_ring_prios(priv);
+}
+
+int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data)
+{
+	struct enetc_ndev_priv *priv = netdev_priv(ndev);
+	struct tc_mqprio_qopt *mqprio = type_data;
+	struct enetc_hw *hw = &priv->si->hw;
+	int num_stack_tx_queues = 0;
+	u8 num_tc = mqprio->num_tc;
+	struct enetc_bdr *tx_ring;
+	int offset, count;
+	int err, tc, q;
 
+	if (!num_tc) {
+		enetc_reset_tc_mqprio(ndev);
 		return 0;
 	}
 
-	/* For the moment, we use only one BD ring per TC.
-	 *
-	 * Configure num_tc BD rings with increasing priorities.
-	 */
-	for (i = 0; i < num_tc; i++) {
-		tx_ring = priv->tx_ring[i];
-		tx_ring->prio = i;
-		enetc_set_bdr_prio(hw, tx_ring->index, tx_ring->prio);
+	err = netdev_set_num_tc(ndev, num_tc);
+	if (err)
+		return err;
+
+	for (tc = 0; tc < num_tc; tc++) {
+		offset = mqprio->offset[tc];
+		count = mqprio->count[tc];
+
+		err = netdev_set_tc_queue(ndev, tc, count, offset);
+		if (err)
+			goto err_reset_tc;
+
+		for (q = offset; q < offset + count; q++) {
+			tx_ring = priv->tx_ring[q];
+			/* The prio_tc_map is skb_tx_hash()'s way of selecting
+			 * between TX queues based on skb->priority. As such,
+			 * there's nothing to offload based on it.
+			 * Make the mqprio "traffic class" be the priority of
+			 * this ring group, and leave the Tx IPV to traffic
+			 * class mapping as its default mapping value of 1:1.
+			 */
+			tx_ring->prio = tc;
+			enetc_set_bdr_prio(hw, tx_ring->index, tx_ring->prio);
+
+			num_stack_tx_queues++;
+		}
 	}
 
-	/* Reset the number of netdev queues based on the TC count */
-	netif_set_real_num_tx_queues(ndev, num_tc);
-	priv->min_num_stack_tx_queues = num_tc;
+	err = netif_set_real_num_tx_queues(ndev, num_stack_tx_queues);
+	if (err)
+		goto err_reset_tc;
 
-	netdev_set_num_tc(ndev, num_tc);
+	priv->min_num_stack_tx_queues = num_stack_tx_queues;
 
-	/* Each TC is associated with one netdev queue */
-	for (i = 0; i < num_tc; i++)
-		netdev_set_tc_queue(ndev, i, 1, i);
+	enetc_debug_tx_ring_prios(priv);
 
 	return 0;
+
+err_reset_tc:
+	enetc_reset_tc_mqprio(ndev);
+	return err;
 }
 EXPORT_SYMBOL_GPL(enetc_setup_tc_mqprio);