From: Erez Shitrit <erezsh@mellanox.com>
Date: Thu, 19 Oct 2017 07:56:42 +0300
Subject: IB/ipoib: Get rid of the tx_outstanding variable in all modes
Patch-mainline: v4.15-rc1
Git-commit: 2c104ea68350b7f49c4ae207afa6e7f7f5c81546
References: bsc#1096793 FATE#325050
The first step toward using NAPI in the UD/TX flow is to separate
between two flows, the NAPI and the xmit, meaning no use of shared
variables between both flows.
This patch takes out the tx_outstanding variable that was used in both
flows and instead the driver uses the 2 cyclic ring variables: tx_head
and tx_tail, tx_head used in the xmit flow and tx_tail in the NAPI flow.
Cc: Kamal Heib <kamalh@mellanox.com>
Signed-off-by: Erez Shitrit <erezsh@mellanox.com>
Reviewed-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/infiniband/ulp/ipoib/ipoib.h | 1 -
drivers/infiniband/ulp/ipoib/ipoib_cm.c | 10 ++++++----
drivers/infiniband/ulp/ipoib/ipoib_ib.c | 10 ++++------
3 files changed, 10 insertions(+), 11 deletions(-)
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -381,7 +381,6 @@ struct ipoib_dev_priv {
unsigned tx_tail;
struct ib_sge tx_sge[MAX_SKB_FRAGS + 1];
struct ib_ud_wr tx_wr;
- unsigned tx_outstanding;
struct ib_wc send_wc[MAX_SEND_CQE];
struct ib_recv_wr rx_wr;
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -769,8 +769,8 @@ void ipoib_cm_send(struct net_device *de
} else {
netif_trans_update(dev);
++tx->tx_head;
-
- if (++priv->tx_outstanding == ipoib_sendq_size) {
+ ++priv->tx_head;
+ if ((priv->tx_head - priv->tx_tail) == ipoib_sendq_size) {
ipoib_dbg(priv, "TX ring 0x%x full, stopping kernel net queue\n",
tx->qp->qp_num);
netif_stop_queue(dev);
@@ -814,7 +814,8 @@ void ipoib_cm_handle_tx_wc(struct net_de
netif_tx_lock(dev);
++tx->tx_tail;
- if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
+ ++priv->tx_tail;
+ if (unlikely((priv->tx_head - priv->tx_tail) == ipoib_sendq_size >> 1) &&
netif_queue_stopped(dev) &&
test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
netif_wake_queue(dev);
@@ -1220,8 +1221,9 @@ timeout:
ipoib_dma_unmap_tx(priv, tx_req);
dev_kfree_skb_any(tx_req->skb);
++p->tx_tail;
+ ++priv->tx_tail;
netif_tx_lock_bh(p->dev);
- if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
+ if (unlikely(priv->tx_head - priv->tx_tail == ipoib_sendq_size >> 1) &&
netif_queue_stopped(p->dev) &&
test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
netif_wake_queue(p->dev);
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -406,7 +406,7 @@ static void ipoib_ib_handle_tx_wc(struct
dev_kfree_skb_any(tx_req->skb);
++priv->tx_tail;
- if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
+ if (unlikely((priv->tx_head - priv->tx_tail) == ipoib_sendq_size >> 1) &&
netif_queue_stopped(dev) &&
test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
netif_wake_queue(dev);
@@ -611,8 +611,8 @@ int ipoib_send(struct net_device *dev, s
priv->tx_wr.wr.send_flags |= IB_SEND_IP_CSUM;
else
priv->tx_wr.wr.send_flags &= ~IB_SEND_IP_CSUM;
-
- if (++priv->tx_outstanding == ipoib_sendq_size) {
+ /* increase the tx_head after send success, but use it for queue state */
+ if (priv->tx_head - priv->tx_tail == ipoib_sendq_size - 1) {
ipoib_dbg(priv, "TX ring full, stopping kernel net queue\n");
if (ib_req_notify_cq(priv->send_cq, IB_CQ_NEXT_COMP))
ipoib_warn(priv, "request notify on send CQ failed\n");
@@ -627,7 +627,6 @@ int ipoib_send(struct net_device *dev, s
if (unlikely(rc)) {
ipoib_warn(priv, "post_send failed, error %d\n", rc);
++dev->stats.tx_errors;
- --priv->tx_outstanding;
ipoib_dma_unmap_tx(priv, tx_req);
dev_kfree_skb_any(skb);
if (netif_queue_stopped(dev))
@@ -640,7 +639,7 @@ int ipoib_send(struct net_device *dev, s
++priv->tx_head;
}
- if (unlikely(priv->tx_outstanding > MAX_SEND_CQE))
+ if (unlikely(priv->tx_head - priv->tx_tail > MAX_SEND_CQE))
while (poll_tx(priv))
; /* nothing */
@@ -773,7 +772,6 @@ int ipoib_ib_dev_stop_default(struct net
ipoib_dma_unmap_tx(priv, tx_req);
dev_kfree_skb_any(tx_req->skb);
++priv->tx_tail;
- --priv->tx_outstanding;
}
for (i = 0; i < ipoib_recvq_size; ++i) {