Re: [PATCH v3 1/5] ethdev: add rx interrupt enable/disable functions

On Thu, Feb 19, 2015 at 07:58:38AM +0000, Zhou, Danny wrote:

quoted

-----Original Message-----
From: Neil Horman [mailto:nhorman-2XuSBdqkA4R54TAoqtyWWQ@public.gmane.org]
Sent: Tuesday, February 17, 2015 11:55 PM
To: Zhou, Danny
Cc: dev-VfR2kkLFssw@public.gmane.org
Subject: Re: [dpdk-dev] [PATCH v3 1/5] ethdev: add rx interrupt enable/disable functions

On Tue, Feb 17, 2015 at 09:47:15PM +0800, Zhou Danny wrote:

quoted

v3 changes
- Add return value for interrupt enable/disable functions

Add two dev_ops functions to enable and disable rx queue interrupts

Signed-off-by: Danny Zhou <redacted>
Tested-by: Yong Liu <redacted>
---
 lib/librte_ether/rte_ethdev.c | 43 ++++++++++++++++++++++++++++++++
 lib/librte_ether/rte_ethdev.h | 57 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 100 insertions(+)

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index ea3a1fb..d27469a 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c

@@ -2825,6 +2825,49 @@ _rte_eth_dev_callback_process(struct rte_eth_dev *dev,
 	}
 	rte_spinlock_unlock(&rte_eth_dev_cb_lock);
 }
+
+int
+rte_eth_dev_rx_queue_intr_enable(uint8_t port_id,
+				uint16_t queue_id)
+{
+	struct rte_eth_dev *dev;
+
+	if (port_id >= nb_ports) {
+		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
+		return (-ENODEV);
+	}
+
+	dev = &rte_eth_devices[port_id];
+	if (dev == NULL) {
+		PMD_DEBUG_TRACE("Invalid port device\n");
+		return (-ENODEV);
+	}
+
+	FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_intr_enable, -ENOTSUP);
+	return (*dev->dev_ops->rx_queue_intr_enable)(dev, queue_id);
+}
+
+int
+rte_eth_dev_rx_queue_intr_disable(uint8_t port_id,
+				uint16_t queue_id)
+{
+	struct rte_eth_dev *dev;
+
+	if (port_id >= nb_ports) {
+		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
+		return (-ENODEV);
+	}
+
+	dev = &rte_eth_devices[port_id];
+	if (dev == NULL) {
+		PMD_DEBUG_TRACE("Invalid port device\n");
+		return (-ENODEV);
+	}
+
+	FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_intr_disable, -ENOTSUP);
+	return (*dev->dev_ops->rx_queue_intr_disable)(dev, queue_id);
+}
+
 #ifdef RTE_NIC_BYPASS
 int rte_eth_dev_bypass_init(uint8_t port_id)
 {

diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 84160c3..0f320a9 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h

@@ -848,6 +848,8 @@ struct rte_eth_fdir {
 struct rte_intr_conf {
 	/** enable/disable lsc interrupt. 0 (default) - disable, 1 enable */
 	uint16_t lsc;
+	/** enable/disable rxq interrupt. 0 (default) - disable, 1 enable */
+	uint16_t rxq;
 };

 /**

@@ -1109,6 +1111,14 @@ typedef int (*eth_tx_queue_setup_t)(struct rte_eth_dev *dev,
 				    const struct rte_eth_txconf *tx_conf);
 /**< @internal Setup a transmit queue of an Ethernet device. */

+typedef int (*eth_rx_enable_intr_t)(struct rte_eth_dev *dev,
+				    uint16_t rx_queue_id);
+/**< @internal Enable interrupt of a receive queue of an Ethernet device. */
+
+typedef int (*eth_rx_disable_intr_t)(struct rte_eth_dev *dev,
+				    uint16_t rx_queue_id);
+/**< @internal Disable interrupt of a receive queue of an Ethernet device. */
+
 typedef void (*eth_queue_release_t)(void *queue);
 /**< @internal Release memory resources allocated by given RX/TX queue. */

@@ -1445,6 +1455,8 @@ struct eth_dev_ops {
 	eth_queue_start_t          tx_queue_start;/**< Start TX for a queue.*/
 	eth_queue_stop_t           tx_queue_stop;/**< Stop TX for a queue.*/
 	eth_rx_queue_setup_t       rx_queue_setup;/**< Set up device RX queue.*/
+	eth_rx_enable_intr_t       rx_queue_intr_enable; /**< Enable Rx queue interrupt. */
+	eth_rx_disable_intr_t      rx_queue_intr_disable; /**< Disable Rx queue interrupt.*/

Put these at the end of eth_dev_ops if you want to avoid breaking ABI

I purposely add those two APIs at current position to ensure all rxq related APIs are declared together
in eth_dev_ops. Anyway, moving them to the end is ok to me for the reason of ABI, though the code looks
a little bit ugly.

Right, pretty isn't a reason to break ABI as noted in the release notes doc

Neil

quoted

quoted

 	eth_queue_release_t        rx_queue_release;/**< Release RX queue.*/
 	eth_rx_queue_count_t       rx_queue_count; /**< Get Rx queue count. */
 	eth_rx_descriptor_done_t   rx_descriptor_done;  /**< Check rxd DD bit */

@@ -2811,6 +2823,51 @@ void _rte_eth_dev_callback_process(struct rte_eth_dev *dev,
 				enum rte_eth_event_type event);

 /**
+ * When there is no rx packet coming in Rx Queue for a long time, we can
+ * sleep lcore related to RX Queue for power saving, and enable rx interrupt
+ * to be triggered when rx packect arrives.
+ *
+ * The rte_eth_dev_rx_queue_intr_enable() function enables rx queue
+ * interrupt on specific rx queue of a port.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param queue_id
+ *   The index of the receive queue from which to retrieve input packets.
+ *   The value must be in the range [0, nb_rx_queue - 1] previously supplied
+ *   to rte_eth_dev_configure().
+ * @return
+ *   - (0) if successful.
+ *   - (-ENOTSUP) if underlying hardware OR driver doesn't support
+ *     that operation.
+ *   - (-ENODEV) if *port_id* invalid.
+ */
+int rte_eth_dev_rx_queue_intr_enable(uint8_t port_id,
+				uint16_t queue_id);
+
+/**
+ * When lcore wakes up from rx interrupt indicating packet coming, disable rx
+ * interrupt and returns to polling mode.
+ *
+ * The rte_eth_dev_rx_queue_intr_disable() function disables rx queue
+ * interrupt on specific rx queue of a port.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param queue_id
+ *   The index of the receive queue from which to retrieve input packets.
+ *   The value must be in the range [0, nb_rx_queue - 1] previously supplied
+ *   to rte_eth_dev_configure().
+ * @return
+ *   - (0) if successful.
+ *   - (-ENOTSUP) if underlying hardware OR driver doesn't support
+ *     that operation.
+ *   - (-ENODEV) if *port_id* invalid.
+ */
+int rte_eth_dev_rx_queue_intr_disable(uint8_t port_id,
+				uint16_t queue_id);
+
+/**
  * Turn on the LED on the Ethernet device.
  * This function turns on the LED on the Ethernet device.
  *
--

1.8.1.4