| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | From 3aa939c73c176690a9ebe646612cd097f281efe5 Mon Sep 17 00:00:00 2001 |
| 2 | From: Camelia Groza <camelia.groza@nxp.com> |
| 3 | Date: Fri, 24 Nov 2017 10:48:31 +0200 |
| 4 | Subject: [PATCH] sdk_dpaa: ceetm: stop transmitting frames when the CQ is |
| 5 | congested |
| 6 | |
| 7 | When the egress CQ is congested, drop the frames instead of enqueueing |
| 8 | them. This is more efficient than enqueueing and receiving them back on |
| 9 | the ERN queue. |
| 10 | |
| 11 | We also can't stop the netdev queues because that would affect all the CQs |
| 12 | and would hinder prioritization. |
| 13 | |
| 14 | Signed-off-by: Camelia Groza <camelia.groza@nxp.com> |
| 15 | --- |
| 16 | .../ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c | 22 ++++++++++++++++------ |
| 17 | .../ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.h | 1 + |
| 18 | 2 files changed, 17 insertions(+), 6 deletions(-) |
| 19 | |
| 20 | --- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c |
| 21 | +++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c |
| 22 | @@ -125,16 +125,16 @@ static void ceetm_cscn(struct qm_ceetm_c |
| 23 | break; |
| 24 | } |
| 25 | |
| 26 | + ceetm_fq->congested = congested; |
| 27 | + |
| 28 | if (congested) { |
| 29 | dpa_priv->cgr_data.congestion_start_jiffies = jiffies; |
| 30 | - netif_tx_stop_all_queues(dpa_priv->net_dev); |
| 31 | dpa_priv->cgr_data.cgr_congested_count++; |
| 32 | if (cstats) |
| 33 | cstats->congested_count++; |
| 34 | } else { |
| 35 | dpa_priv->cgr_data.congested_jiffies += |
| 36 | (jiffies - dpa_priv->cgr_data.congestion_start_jiffies); |
| 37 | - netif_tx_wake_all_queues(dpa_priv->net_dev); |
| 38 | } |
| 39 | } |
| 40 | |
| 41 | @@ -148,6 +148,7 @@ static int ceetm_alloc_fq(struct ceetm_f |
| 42 | |
| 43 | (*fq)->net_dev = dev; |
| 44 | (*fq)->ceetm_cls = cls; |
| 45 | + (*fq)->congested = 0; |
| 46 | return 0; |
| 47 | } |
| 48 | |
| 49 | @@ -1913,7 +1914,8 @@ int __hot ceetm_tx(struct sk_buff *skb, |
| 50 | struct Qdisc *sch = net_dev->qdisc; |
| 51 | struct ceetm_class *cl; |
| 52 | struct dpa_priv_s *priv_dpa; |
| 53 | - struct qman_fq *egress_fq, *conf_fq; |
| 54 | + struct ceetm_fq *ceetm_fq; |
| 55 | + struct qman_fq *conf_fq; |
| 56 | struct ceetm_qdisc *priv = qdisc_priv(sch); |
| 57 | struct ceetm_qdisc_stats *qstats = this_cpu_ptr(priv->root.qstats); |
| 58 | struct ceetm_class_stats *cstats; |
| 59 | @@ -1945,11 +1947,11 @@ int __hot ceetm_tx(struct sk_buff *skb, |
| 60 | */ |
| 61 | switch (cl->type) { |
| 62 | case CEETM_PRIO: |
| 63 | - egress_fq = &cl->prio.fq->fq; |
| 64 | + ceetm_fq = cl->prio.fq; |
| 65 | cstats = this_cpu_ptr(cl->prio.cstats); |
| 66 | break; |
| 67 | case CEETM_WBFS: |
| 68 | - egress_fq = &cl->wbfs.fq->fq; |
| 69 | + ceetm_fq = cl->wbfs.fq; |
| 70 | cstats = this_cpu_ptr(cl->wbfs.cstats); |
| 71 | break; |
| 72 | default: |
| 73 | @@ -1957,8 +1959,16 @@ int __hot ceetm_tx(struct sk_buff *skb, |
| 74 | goto drop; |
| 75 | } |
| 76 | |
| 77 | + /* If the FQ is congested, avoid enqueuing the frame and dropping it |
| 78 | + * when it returns on the ERN path. Drop it here directly instead. |
| 79 | + */ |
| 80 | + if (unlikely(ceetm_fq->congested)) { |
| 81 | + qstats->drops++; |
| 82 | + goto drop; |
| 83 | + } |
| 84 | + |
| 85 | bstats_update(&cstats->bstats, skb); |
| 86 | - return dpa_tx_extended(skb, net_dev, egress_fq, conf_fq); |
| 87 | + return dpa_tx_extended(skb, net_dev, &ceetm_fq->fq, conf_fq); |
| 88 | |
| 89 | drop: |
| 90 | dev_kfree_skb_any(skb); |
| 91 | --- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.h |
| 92 | +++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.h |
| 93 | @@ -105,6 +105,7 @@ struct ceetm_fq { |
| 94 | struct qman_fq fq; |
| 95 | struct net_device *net_dev; |
| 96 | struct ceetm_class *ceetm_cls; |
| 97 | + int congested; /* Congestion status */ |
| 98 | }; |
| 99 | |
| 100 | struct root_q { |