Re: [dpdk-dev] [PATCH] ethdev: get rxq interrupt fd

["Li, Xiaoyun" <xiaoyun.li@intel.com>]

Sure. Anyway there is an error log to indicate the error.
I will send v3 later. Thanks.

From: Stephen Hemminger [mailto:stephen@networkplumber.org]
Sent: Friday, September 28, 2018 20:47
To: Li, Xiaoyun <xiaoyun.li@intel.com>
Cc: Yigit, Ferruh <ferruh.yigit@intel.com>; Thomas Monjalon <thomas@monjalon.net>; Zhang, Helin <helin.zhang@intel.com>; damarion@cisco.com; Kinsella, Ray <ray.kinsella@intel.com>; dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] ethdev: get rxq interrupt fd

In general, an API is less error prone if it only does return by value. What about just returning fd or -1?


On Fri, Sep 28, 2018, 5:55 AM Xiaoyun Li <xiaoyun.li@intel.com<mailto:xiaoyun.li@intel.com>> wrote:
Some users want to use their own epoll instances to control both
DPDK rxq interrupt fds and their own other fds. So added a function
to get rxq interrupt fd based on port id and queue id.

Signed-off-by: Xiaoyun Li <xiaoyun.li@intel.com<mailto:xiaoyun.li@intel.com>>
---
 lib/librte_ethdev/rte_ethdev.c | 37 ++++++++++++++++++++++++++++++++++
 lib/librte_ethdev/rte_ethdev.h |  3 +++
 2 files changed, 40 insertions(+)

diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
index ef99f7068..c21124e32 100644
--- a/lib/librte_ethdev/rte_ethdev.c
+++ b/lib/librte_ethdev/rte_ethdev.c
@@ -3433,6 +3433,43 @@ rte_eth_dev_rx_intr_ctl(uint16_t port_id, int epfd, int op, void *data)
        return 0;
 }

+int
+rte_eth_dev_rx_intr_ctl_q_get_fd(uint16_t port_id, uint16_t queue_id,
+                                int *fd)
+{
+       struct rte_intr_handle *intr_handle;
+       struct rte_eth_dev *dev;
+       unsigned int efd_idx;
+       uint32_t vec;
+
+       RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
+
+       dev = &rte_eth_devices[port_id];
+
+       if (queue_id >= dev->data->nb_rx_queues) {
+               RTE_ETHDEV_LOG(ERR, "Invalid RX queue_id=%u\n", queue_id);
+               return -EINVAL;
+       }
+
+       if (!dev->intr_handle) {
+               RTE_ETHDEV_LOG(ERR, "RX Intr handle unset\n");
+               return -ENOTSUP;
+       }
+
+       intr_handle = dev->intr_handle;
+       if (!intr_handle->intr_vec) {
+               RTE_ETHDEV_LOG(ERR, "RX Intr vector unset\n");
+               return -EPERM;
+       }
+
+       vec = intr_handle->intr_vec[queue_id];
+       efd_idx = (vec >= RTE_INTR_VEC_RXTX_OFFSET) ?
+               (vec - RTE_INTR_VEC_RXTX_OFFSET) : vec;
+       *fd = intr_handle->efds[efd_idx];
+
+       return 0;
+}
+
 const struct rte_memzone *
 rte_eth_dma_zone_reserve(const struct rte_eth_dev *dev, const char *ring_name,
                         uint16_t queue_id, size_t size, unsigned align,
diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h
index 012577b0a..3670d7249 100644
--- a/lib/librte_ethdev/rte_ethdev.h
+++ b/lib/librte_ethdev/rte_ethdev.h
@@ -2719,6 +2719,9 @@ int rte_eth_dev_rx_intr_ctl(uint16_t port_id, int epfd, int op, void *data);
 int rte_eth_dev_rx_intr_ctl_q(uint16_t port_id, uint16_t queue_id,
                              int epfd, int op, void *data);

+int rte_eth_dev_rx_intr_ctl_q_get_fd(uint16_t port_id, uint16_t queue_id,
+                                    int *fd);
+
 /**
  * Turn on the LED on the Ethernet device.
  * This function turns on the LED on the Ethernet device.
--
2.17.1