layerscape: add patches-5.4

[openwrt/staging/wigyori.git] / target / linux / layerscape / patches-5.4 / 701-net-0043-sdk_dpaa-ceetm-stop-transmitting-frames-when-the-CQ-.patch

diff --git a/target/linux/layerscape/patches-5.4/701-net-0043-sdk_dpaa-ceetm-stop-transmitting-frames-when-the-CQ-.patch b/target/linux/layerscape/patches-5.4/701-net-0043-sdk_dpaa-ceetm-stop-transmitting-frames-when-the-CQ-.patch
new file mode 100644 (file)
index 0000000..1f1afe3
--- /dev/null
+++ b/target/linux/layerscape/patches-5.4/701-net-0043-sdk_dpaa-ceetm-stop-transmitting-frames-when-the-CQ-.patch
@@ -0,0 +1,100 @@
+From 3aa939c73c176690a9ebe646612cd097f281efe5 Mon Sep 17 00:00:00 2001
+From: Camelia Groza <camelia.groza@nxp.com>
+Date: Fri, 24 Nov 2017 10:48:31 +0200
+Subject: [PATCH] sdk_dpaa: ceetm: stop transmitting frames when the CQ is
+ congested
+
+When the egress CQ is congested, drop the frames instead of enqueueing
+them. This is more efficient than enqueueing and receiving them back on
+the ERN queue.
+
+We also can't stop the netdev queues because that would affect all the CQs
+and would hinder prioritization.
+
+Signed-off-by: Camelia Groza <camelia.groza@nxp.com>
+---
+ .../ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c   | 22 ++++++++++++++++------
+ .../ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.h   |  1 +
+ 2 files changed, 17 insertions(+), 6 deletions(-)
+
+--- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c
++++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.c
+@@ -125,16 +125,16 @@ static void ceetm_cscn(struct qm_ceetm_c
+               break;
+       }
+ 
++      ceetm_fq->congested = congested;
++
+       if (congested) {
+               dpa_priv->cgr_data.congestion_start_jiffies = jiffies;
+-              netif_tx_stop_all_queues(dpa_priv->net_dev);
+               dpa_priv->cgr_data.cgr_congested_count++;
+               if (cstats)
+                       cstats->congested_count++;
+       } else {
+               dpa_priv->cgr_data.congested_jiffies +=
+                       (jiffies - dpa_priv->cgr_data.congestion_start_jiffies);
+-              netif_tx_wake_all_queues(dpa_priv->net_dev);
+       }
+ }
+ 
+@@ -148,6 +148,7 @@ static int ceetm_alloc_fq(struct ceetm_f
+ 
+       (*fq)->net_dev = dev;
+       (*fq)->ceetm_cls = cls;
++      (*fq)->congested = 0;
+       return 0;
+ }
+ 
+@@ -1913,7 +1914,8 @@ int __hot ceetm_tx(struct sk_buff *skb,
+       struct Qdisc *sch = net_dev->qdisc;
+       struct ceetm_class *cl;
+       struct dpa_priv_s *priv_dpa;
+-      struct qman_fq *egress_fq, *conf_fq;
++      struct ceetm_fq *ceetm_fq;
++      struct qman_fq *conf_fq;
+       struct ceetm_qdisc *priv = qdisc_priv(sch);
+       struct ceetm_qdisc_stats *qstats = this_cpu_ptr(priv->root.qstats);
+       struct ceetm_class_stats *cstats;
+@@ -1945,11 +1947,11 @@ int __hot ceetm_tx(struct sk_buff *skb,
+        */
+       switch (cl->type) {
+       case CEETM_PRIO:
+-              egress_fq = &cl->prio.fq->fq;
++              ceetm_fq = cl->prio.fq;
+               cstats = this_cpu_ptr(cl->prio.cstats);
+               break;
+       case CEETM_WBFS:
+-              egress_fq = &cl->wbfs.fq->fq;
++              ceetm_fq = cl->wbfs.fq;
+               cstats = this_cpu_ptr(cl->wbfs.cstats);
+               break;
+       default:
+@@ -1957,8 +1959,16 @@ int __hot ceetm_tx(struct sk_buff *skb,
+               goto drop;
+       }
+ 
++      /* If the FQ is congested, avoid enqueuing the frame and dropping it
++       * when it returns on the ERN path. Drop it here directly instead.
++       */
++      if (unlikely(ceetm_fq->congested)) {
++              qstats->drops++;
++              goto drop;
++      }
++
+       bstats_update(&cstats->bstats, skb);
+-      return dpa_tx_extended(skb, net_dev, egress_fq, conf_fq);
++      return dpa_tx_extended(skb, net_dev, &ceetm_fq->fq, conf_fq);
+ 
+ drop:
+       dev_kfree_skb_any(skb);
+--- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.h
++++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_ceetm.h
+@@ -105,6 +105,7 @@ struct ceetm_fq {
+       struct qman_fq fq;
+       struct net_device *net_dev;
+       struct ceetm_class *ceetm_cls;
++      int congested; /* Congestion status */
+ };
+ 
+ struct root_q {