Re: [dpdk-dev] [PATCH 4/7] vmxnet3: fix link state handling

[Yong Wang <yongwang@vmware.com>]

On 12/16/14, 9:13 PM, "Stephen Hemminger" <stephen@networkplumber.org>
wrote:

>From: Stephen Hemminger <shemming@brocade.com>
>
>This patch is a bugfx.
>
>The Intel version of VMXNET3 driver does not handle link state properly.
>The VMXNET3 API returns 1 if connected and 0 if disconnected.
>Also need to return correct value to indicate state change.
>
>Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
>---

Acked-by: Yong Wang <yongwang@vmware.com>

One nit below:


> lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c | 53
>+++++++++++++++++++++++----------
> 1 file changed, 38 insertions(+), 15 deletions(-)
>
>diff --git a/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
>b/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
>index 4947c78..7afb43f 100644
>--- a/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
>+++ b/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
>@@ -157,9 +157,36 @@ gpa_zone_reserve(struct rte_eth_dev *dev, uint32_t
>size,
>  *   - On success, zero.
>  *   - On failure, negative value.
>  */
>-static inline int
>-rte_vmxnet3_dev_atomic_write_link_status(struct rte_eth_dev *dev,
>-				struct rte_eth_link *link)
>+
>+static int
>+vmxnet3_dev_atomic_read_link_status(struct rte_eth_dev *dev,
>+				    struct rte_eth_link *link)
>+{
>+	struct rte_eth_link *dst = link;
>+	struct rte_eth_link *src = &(dev->data->dev_link);
>+
>+	if (rte_atomic64_cmpset((uint64_t *)dst, *(uint64_t *)dst,
>+				*(uint64_t *)src) == 0)
>+		return -1;
>+
>+	return 0;
>+}
>+
>+/**
>+ * Atomically writes the link status information into global
>+ * structure rte_eth_dev.
>+ *
>+ * @param dev
>+ *   - Pointer to the structure rte_eth_dev to read from.

"to write to" here.

>+ *   - Pointer to the buffer to be saved with the link status.
>+ *
>+ * @return
>+ *   - On success, zero.
>+ *   - On failure, negative value.
>+ */
>+static int
>+vmxnet3_dev_atomic_write_link_status(struct rte_eth_dev *dev,
>+				     struct rte_eth_link *link)
> {
> 	struct rte_eth_link *dst = &(dev->data->dev_link);
> 	struct rte_eth_link *src = link;
>@@ -576,7 +603,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> 
> 	/* Clear recorded link status */
> 	memset(&link, 0, sizeof(link));
>-	rte_vmxnet3_dev_atomic_write_link_status(dev, &link);
>+	vmxnet3_dev_atomic_write_link_status(dev, &link);
> }
> 
> /*
>@@ -658,28 +685,24 @@ static int
> vmxnet3_dev_link_update(struct rte_eth_dev *dev, __attribute__((unused))
>int wait_to_complete)
> {
> 	struct vmxnet3_hw *hw = dev->data->dev_private;
>-	struct rte_eth_link link;
>+	struct rte_eth_link old, link;
> 	uint32_t ret;
> 
>+	memset(&link, 0, sizeof(link));
>+	vmxnet3_dev_atomic_read_link_status(dev, &old);
>+
> 	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD, VMXNET3_CMD_GET_LINK);
> 	ret = VMXNET3_READ_BAR1_REG(hw, VMXNET3_REG_CMD);
> 
>-	if (!ret) {
>-		PMD_INIT_LOG(ERR, "Link Status Negative : %s()", __func__);
>-		return -1;
>-	}
>-
> 	if (ret & 0x1) {
> 		link.link_status = 1;
> 		link.link_duplex = ETH_LINK_FULL_DUPLEX;
> 		link.link_speed = ETH_LINK_SPEED_10000;
>-
>-		rte_vmxnet3_dev_atomic_write_link_status(dev, &link);
>-
>-		return 0;
> 	}
> 
>-	return -1;
>+	vmxnet3_dev_atomic_write_link_status(dev, &link);
>+
>+	return (old.link_status == link.link_status) ? -1 : 0;
> }
> 
> /* Updating rxmode through Vmxnet3_DriverShared structure in adapter */
>-- 
>2.1.3
>