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From: Shannon Nelson <shannon.nelson@oracle.com>
To: netdev@vger.kernel.org, davem@davemloft.net
Cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org,
	Shannon Nelson <shannon.nelson@oracle.com>
Subject: [PATCH v4 net-next 4/8] sunvnet: add memory barrier before check for tx enable
Date: Mon, 13 Feb 2017 10:57:00 -0800	[thread overview]
Message-ID: <1487012224-403399-5-git-send-email-shannon.nelson@oracle.com> (raw)
In-Reply-To: <1487012224-403399-1-git-send-email-shannon.nelson@oracle.com>

In order to allow the underlying LDC and outstanding memory operations
to potentially catch up with the driver's Tx requests, add a memory
barrier before checking again for available tx descriptors.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
---
 drivers/net/ethernet/sun/sunvnet_common.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/sun/sunvnet_common.c b/drivers/net/ethernet/sun/sunvnet_common.c
index 0f940f0..623363b 100644
--- a/drivers/net/ethernet/sun/sunvnet_common.c
+++ b/drivers/net/ethernet/sun/sunvnet_common.c
@@ -1427,6 +1427,7 @@ int sunvnet_start_xmit_common(struct sk_buff *skb, struct net_device *dev,
 	dr->prod = (dr->prod + 1) & (VNET_TX_RING_SIZE - 1);
 	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
 		netif_tx_stop_queue(txq);
+		smp_rmb();
 		if (vnet_tx_dring_avail(dr) > VNET_TX_WAKEUP_THRESH(dr))
 			netif_tx_wake_queue(txq);
 	}
-- 
1.7.1

  parent reply	other threads:[~2017-02-13 19:00 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-02-13 18:56 [PATCH v4 net-next 0/8] sunvnet driver updates Shannon Nelson
2017-02-13 18:56 ` [PATCH v4 net-next 1/8] sunvnet: make sunvnet common code dynamically loadable Shannon Nelson
2017-02-13 18:56 ` [PATCH v4 net-next 2/8] sunvnet: remove unused variable in maybe_tx_wakeup Shannon Nelson
2017-02-13 18:56 ` [PATCH v4 net-next 3/8] sunvnet: update version and version printing Shannon Nelson
2017-02-13 18:57 ` Shannon Nelson [this message]
2017-02-13 18:57 ` [PATCH v4 net-next 5/8] sunvnet: straighten up message event handling logic Shannon Nelson
2017-02-13 19:06   ` Joe Perches
2017-02-13 19:18     ` Shannon Nelson
2017-02-13 18:57 ` [PATCH v4 net-next 6/8] sunvnet: remove extra rcu_read_unlocks Shannon Nelson
2017-02-13 18:57 ` [PATCH v4 net-next 7/8] ldmvsw: update and simplify version string Shannon Nelson
2017-02-13 18:57 ` [PATCH v4 net-next 8/8] ldmvsw: disable tso and gso for bridge operations Shannon Nelson
2017-02-14 18:04 ` [PATCH v4 net-next 0/8] sunvnet driver updates David Miller

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