On 01/16/2018 09:37 PM, Stephen Hemminger wrote:
Many drivers are all doing copy/paste of the same code to atomically
update the link status. Reduce duplication, and allow for future
changes by having common function for this.
Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
---
lib/librte_ether/rte_ethdev.c | 22 +++------------
lib/librte_ether/rte_ethdev.h | 62 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 66 insertions(+), 18 deletions(-)
diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index a524af740f4a..d6433af35a19 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -1447,20 +1447,6 @@ rte_eth_allmulticast_get(uint16_t port_id)
return dev->data->all_multicast;
}
-static inline int
-rte_eth_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;
-}
-
void
rte_eth_link_get(uint16_t port_id, struct rte_eth_link *eth_link)
{
@@ -1469,8 +1455,8 @@ rte_eth_link_get(uint16_t port_id, struct rte_eth_link
*eth_link)
RTE_ETH_VALID_PORTID_OR_RET(port_id);
dev = &rte_eth_devices[port_id];
- if (dev->data->dev_conf.intr_conf.lsc != 0)
- rte_eth_dev_atomic_read_link_status(dev, eth_link);
+ if (dev->data->dev_conf.intr_conf.lsc)
+ rte_eth_linkstatus_get(dev, eth_link);
else {
RTE_FUNC_PTR_OR_RET(*dev->dev_ops->link_update);
(*dev->dev_ops->link_update)(dev, 1);
@@ -1486,8 +1472,8 @@ rte_eth_link_get_nowait(uint16_t port_id, struct
rte_eth_link *eth_link)
RTE_ETH_VALID_PORTID_OR_RET(port_id);
dev = &rte_eth_devices[port_id];
- if (dev->data->dev_conf.intr_conf.lsc != 0)
- rte_eth_dev_atomic_read_link_status(dev, eth_link);
+ if (dev->data->dev_conf.intr_conf.lsc)
+ rte_eth_linkstatus_get(dev, eth_link);
else {
RTE_FUNC_PTR_OR_RET(*dev->dev_ops->link_update);
(*dev->dev_ops->link_update)(dev, 0);
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index b10e2a92da71..ec8255656967 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -2218,6 +2218,68 @@ int rte_eth_dev_set_link_down(uint16_t port_id);
*/
void rte_eth_dev_close(uint16_t port_id);
+
+/**
+ * @internal
+ * Atomically set the link status for the specific device.
+ * It is for use by DPDK device driver use only.
+ * User applications should not call it
+ *
+ * @param dev
+ * Pointer to struct rte_eth_dev.
+ * @param link
+ * New link status value.
+ * @return
+ * 1 if link status has changed;
+ * 0 if link status is unchanged.
Here "link status" is used as up/down status of the link.
+ */
+static inline int
+rte_eth_linkstatus_set(struct rte_eth_dev *dev,
+ const struct rte_eth_link *new_link)
Here (and function and the second parameter description) "link status"
is used as all information about link.
rte_ethdev API calls it just "link" (link_update, link_get_wait/nowait).
It is not a big problem, but it is better to avoid it.
Thanks.
+{
+ volatile uint64_t *dev_link
+ = (volatile uint64_t *)&(dev->data->dev_link);
+ union {
+ uint64_t val64;
+ struct rte_eth_link link;
+ } orig;
+
+ RTE_BUILD_BUG_ON(sizeof(*new_link) != sizeof(uint64_t));
+
+ orig.val64 = rte_atomic64_exchange(dev_link,
+ *(const uint64_t *)new_link);
+
+ return orig.link.link_status != new_link->link_status;
+}
+
+/**
+ * @internal
+ * Atomically get the link speed and status.
+ *
+ * @param dev
+ * Pointer to struct rte_eth_dev.
+ * @param link
+ * link status value.
+ */
+static inline void
+rte_eth_linkstatus_get(const struct rte_eth_dev *dev,
+ struct rte_eth_link *link)
+{
+ volatile uint64_t *src = (uint64_t *)&(dev->data->dev_link);
+ uint64_t *dst = (uint64_t *)link;
+
+ RTE_BUILD_BUG_ON(sizeof(*link) != sizeof(uint64_t));
+
+ /* can't use rte_atomic64_read because it returns signed int */
+#ifdef __LP64__
+ *dst = *src;
+#else
+ do {
+ *dst = *src;
+ } while (!rte_atomic64_cmpset(src, *dst, *dst));
+#endif
+}
+
/**
* Reset a Ethernet device and keep its port id.
*
