[dpdk-dev] [PATCH v3] igb_uio: switch to pci_alloc_irq_vectors()

[Nicolas Dichtel <nicolas.dichtel@6wind.com>]

pci_enable_msix() will be removed in kernel 4.12. The new API is available
since linux 4.8, thus let's use it.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=aff171641d18
Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=4244de1c64de
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Marchand <david.marchand@6wind.com>
Acked-by: Ferruh Yigit <ferruh.yigit@intel.com>
---

v3: move code in compat.h at the end of the file

v2: use compat.h and define HAVE_PCI_ENABLE_MSIX
    limit commit log to 75 columns

 lib/librte_eal/linuxapp/igb_uio/compat.h  |  4 ++++
 lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 11 +++++++++++
 2 files changed, 15 insertions(+)

diff --git a/lib/librte_eal/linuxapp/igb_uio/compat.h b/lib/librte_eal/linuxapp/igb_uio/compat.h
index 0d781e482562..b800a53cd30b 100644
--- a/lib/librte_eal/linuxapp/igb_uio/compat.h
+++ b/lib/librte_eal/linuxapp/igb_uio/compat.h
@@ -123,3 +123,7 @@ static bool pci_check_and_mask_intx(struct pci_dev *pdev)
 }
 
 #endif /* < 3.3.0 */
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 8, 0)
+#define HAVE_PCI_ENABLE_MSIX
+#endif
diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
index 192bd4a96b68..b9d427c51c57 100644
--- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
+++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
@@ -325,7 +325,9 @@ static int
 igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	struct rte_uio_pci_dev *udev;
+#ifdef HAVE_PCI_ENABLE_MSIX
 	struct msix_entry msix_entry;
+#endif
 	dma_addr_t map_dma_addr;
 	void *map_addr;
 	int err;
@@ -381,6 +383,7 @@ igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	switch (igbuio_intr_mode_preferred) {
 	case RTE_INTR_MODE_MSIX:
 		/* Only 1 msi-x vector needed */
+#ifdef HAVE_PCI_ENABLE_MSIX
 		msix_entry.entry = 0;
 		if (pci_enable_msix(dev, &msix_entry, 1) == 0) {
 			dev_dbg(&dev->dev, "using MSI-X");
@@ -389,6 +392,14 @@ igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 			udev->mode = RTE_INTR_MODE_MSIX;
 			break;
 		}
+#else
+		if (pci_alloc_irq_vectors(dev, 1, 1, PCI_IRQ_MSIX) == 1) {
+			dev_dbg(&dev->dev, "using MSI-X");
+			udev->info.irq = pci_irq_vector(dev, 0);
+			udev->mode = RTE_INTR_MODE_MSIX;
+			break;
+		}
+#endif
 		/* fall back to INTX */
 	case RTE_INTR_MODE_LEGACY:
 		if (pci_intx_mask_supported(dev)) {
-- 
2.11.0