lkml.org 
[lkml]   [2019]   [Jul]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.2 15/66] net: stmmac: Re-work the queue selection for TSO packets
Date
From: Jose Abreu <Jose.Abreu@synopsys.com>

[ Upstream commit 4993e5b37e8bcb55ac90f76eb6d2432647273747 ]

Ben Hutchings says:
"This is the wrong place to change the queue mapping.
stmmac_xmit() is called with a specific TX queue locked,
and accessing a different TX queue results in a data race
for all of that queue's state.

I think this commit should be reverted upstream and in all
stable branches. Instead, the driver should implement the
ndo_select_queue operation and override the queue mapping there."

Fixes: c5acdbee22a1 ("net: stmmac: Send TSO packets always from Queue 0")
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 28 ++++++++++++++--------
1 file changed, 18 insertions(+), 10 deletions(-)

--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3048,17 +3048,8 @@ static netdev_tx_t stmmac_xmit(struct sk

/* Manage oversized TCP frames for GMAC4 device */
if (skb_is_gso(skb) && priv->tso) {
- if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)) {
- /*
- * There is no way to determine the number of TSO
- * capable Queues. Let's use always the Queue 0
- * because if TSO is supported then at least this
- * one will be capable.
- */
- skb_set_queue_mapping(skb, 0);
-
+ if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))
return stmmac_tso_xmit(skb, dev);
- }
}

if (unlikely(stmmac_tx_avail(priv, queue) < nfrags + 1)) {
@@ -3875,6 +3866,22 @@ static int stmmac_setup_tc(struct net_de
}
}

+static u16 stmmac_select_queue(struct net_device *dev, struct sk_buff *skb,
+ struct net_device *sb_dev)
+{
+ if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)) {
+ /*
+ * There is no way to determine the number of TSO
+ * capable Queues. Let's use always the Queue 0
+ * because if TSO is supported then at least this
+ * one will be capable.
+ */
+ return 0;
+ }
+
+ return netdev_pick_tx(dev, skb, NULL) % dev->real_num_tx_queues;
+}
+
static int stmmac_set_mac_address(struct net_device *ndev, void *addr)
{
struct stmmac_priv *priv = netdev_priv(ndev);
@@ -4091,6 +4098,7 @@ static const struct net_device_ops stmma
.ndo_tx_timeout = stmmac_tx_timeout,
.ndo_do_ioctl = stmmac_ioctl,
.ndo_setup_tc = stmmac_setup_tc,
+ .ndo_select_queue = stmmac_select_queue,
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = stmmac_poll_controller,
#endif

\
 
 \ /
  Last update: 2019-07-26 17:42    [W:0.298 / U:23.460 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site