[dpdk-dev] [PATCH 2/3] net/virtio: clean up LSC setting

[Jianfeng Tan <jianfeng.tan@intel.com>]

Clean up LSC setting:
  - LSC flag is set in several places, but only the last one takes
    effect; so we just keep the last one.
  - As we already change to use capability list to detect MSI-X, remove
    the redundant MSI-X detection in legacy devices.

Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
---
 drivers/net/virtio/virtio_ethdev.c |  7 ++----
 drivers/net/virtio/virtio_pci.c    | 48 ++------------------------------------
 drivers/net/virtio/virtio_pci.h    |  3 +--
 3 files changed, 5 insertions(+), 53 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index e6c57b3..e79748e 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1353,6 +1353,7 @@ virtio_init_device(struct rte_eth_dev *eth_dev, uint64_t req_features)
 		rte_eth_copy_pci_info(eth_dev, pci_dev);
 	}
 
+	eth_dev->data->dev_flags = RTE_ETH_DEV_DETACHABLE;
 	/* If host does not support both status and MSI-X then disable LSC */
 	if (vtpci_with_feature(hw, VIRTIO_NET_F_STATUS) && hw->use_msix)
 		eth_dev->data->dev_flags |= RTE_ETH_DEV_INTR_LSC;
@@ -1521,7 +1522,6 @@ int
 eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 {
 	struct virtio_hw *hw = eth_dev->data->dev_private;
-	uint32_t dev_flags = RTE_ETH_DEV_DETACHABLE;
 	int ret;
 
 	RTE_BUILD_BUG_ON(RTE_PKTMBUF_HEADROOM < sizeof(struct virtio_net_hdr_mrg_rxbuf));
@@ -1561,14 +1561,11 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	 * virtio_user_eth_dev_alloc() before eth_virtio_dev_init() is called.
 	 */
 	if (!hw->virtio_user_dev) {
-		ret = vtpci_init(RTE_DEV_TO_PCI(eth_dev->device), hw,
-				 &dev_flags);
+		ret = vtpci_init(RTE_DEV_TO_PCI(eth_dev->device), hw);
 		if (ret)
 			return ret;
 	}
 
-	eth_dev->data->dev_flags = dev_flags;
-
 	/* reset device and negotiate default features */
 	ret = virtio_init_device(eth_dev, VIRTIO_PMD_DEFAULT_GUEST_FEATURES);
 	if (ret < 0)
diff --git a/drivers/net/virtio/virtio_pci.c b/drivers/net/virtio/virtio_pci.c
index ecad46e..1df26a6 100644
--- a/drivers/net/virtio/virtio_pci.c
+++ b/drivers/net/virtio/virtio_pci.c
@@ -279,47 +279,6 @@ legacy_notify_queue(struct virtio_hw *hw, struct virtqueue *vq)
 			 VIRTIO_PCI_QUEUE_NOTIFY);
 }
 
-#ifdef RTE_EXEC_ENV_LINUXAPP
-static int
-legacy_virtio_has_msix(const struct rte_pci_addr *loc)
-{
-	DIR *d;
-	char dirname[PATH_MAX];
-
-	snprintf(dirname, sizeof(dirname),
-		     "%s/" PCI_PRI_FMT "/msi_irqs", pci_get_sysfs_path(),
-		     loc->domain, loc->bus, loc->devid, loc->function);
-
-	d = opendir(dirname);
-	if (d)
-		closedir(d);
-
-	return d != NULL;
-}
-#else
-static int
-legacy_virtio_has_msix(const struct rte_pci_addr *loc __rte_unused)
-{
-	/* nic_uio does not enable interrupts, return 0 (false). */
-	return 0;
-}
-#endif
-
-static int
-legacy_virtio_resource_init(struct rte_pci_device *pci_dev,
-			    struct virtio_hw *hw, uint32_t *dev_flags)
-{
-	if (rte_eal_pci_ioport_map(pci_dev, 0, VTPCI_IO(hw)) < 0)
-		return -1;
-
-	if (pci_dev->intr_handle.type != RTE_INTR_HANDLE_UNKNOWN)
-		*dev_flags |= RTE_ETH_DEV_INTR_LSC;
-	else
-		*dev_flags &= ~RTE_ETH_DEV_INTR_LSC;
-
-	return 0;
-}
-
 const struct virtio_pci_ops legacy_ops = {
 	.read_dev_cfg	= legacy_read_dev_config,
 	.write_dev_cfg	= legacy_write_dev_config,
@@ -712,8 +671,7 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw)
  * Return 0 on success.
  */
 int
-vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw,
-	   uint32_t *dev_flags)
+vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw)
 {
 	/*
 	 * Try if we can succeed reading virtio pci caps, which exists
@@ -724,12 +682,11 @@ vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw,
 		PMD_INIT_LOG(INFO, "modern virtio pci detected.");
 		virtio_hw_internal[hw->port_id].vtpci_ops = &modern_ops;
 		hw->modern = 1;
-		*dev_flags |= RTE_ETH_DEV_INTR_LSC;
 		return 0;
 	}
 
 	PMD_INIT_LOG(INFO, "trying with legacy virtio pci.");
-	if (legacy_virtio_resource_init(dev, hw, dev_flags) < 0) {
+	if (rte_eal_pci_ioport_map(dev, 0, VTPCI_IO(hw)) < 0) {
 		if (dev->kdrv == RTE_KDRV_UNKNOWN &&
 		    (!dev->device.devargs ||
 		     dev->device.devargs->type !=
@@ -742,7 +699,6 @@ vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw,
 	}
 
 	virtio_hw_internal[hw->port_id].vtpci_ops = &legacy_ops;
-	hw->use_msix = legacy_virtio_has_msix(&dev->addr);
 	hw->modern   = 0;
 
 	return 0;
diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
index e7290d7..5651eb5 100644
--- a/drivers/net/virtio/virtio_pci.h
+++ b/drivers/net/virtio/virtio_pci.h
@@ -321,8 +321,7 @@ vtpci_with_feature(struct virtio_hw *hw, uint64_t bit)
 /*
  * Function declaration from virtio_pci.c
  */
-int vtpci_init(struct rte_pci_device *, struct virtio_hw *,
-	       uint32_t *dev_flags);
+int vtpci_init(struct rte_pci_device *, struct virtio_hw *);
 void vtpci_reset(struct virtio_hw *);
 
 void vtpci_reinit_complete(struct virtio_hw *);
-- 
2.7.4