[dpdk-dev] [PATCH 04/10] igb_uio: msix cleanups

[Stephen Hemminger]

Since only one MSI-X entry is ever defined, there is no need to
put it as an array in the driver private data structure. One msix_entry
can just be put on the stack and initialized there.

Also remove the unused backport defines related to MSI-X.
I suspect this code was just inherited from some other project and
never cleaned up.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>


--- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c 2014-07-18 08:38:29.291724950 
-0700
+++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c 2014-07-18 08:42:06.460487465 
-0700
@@ -37,19 +37,6 @@
 #endif
 #include <rte_pci_dev_features.h>

-/**
- * MSI-X related macros, copy from linux/pci_regs.h in kernel 2.6.39,
- * but none of them in kernel 2.6.35.
- */
-#ifndef PCI_MSIX_ENTRY_SIZE
-#define PCI_MSIX_ENTRY_SIZE             16
-#define PCI_MSIX_ENTRY_LOWER_ADDR       0
-#define PCI_MSIX_ENTRY_UPPER_ADDR       4
-#define PCI_MSIX_ENTRY_DATA             8
-#define PCI_MSIX_ENTRY_VECTOR_CTRL      12
-#define PCI_MSIX_ENTRY_CTRL_MASKBIT     1
-#endif
-
 #ifdef RTE_PCI_CONFIG
 #define PCI_SYS_FILE_BUF_SIZE      10
 #define PCI_DEV_CAP_REG            0xA4
@@ -59,8 +46,6 @@
 #define PCI_DEV_CTRL_EXT_TAG_MASK  (1 << PCI_DEV_CTRL_EXT_TAG_SHIFT)
 #endif

-#define IGBUIO_NUM_MSI_VECTORS 1
-
 /**
  * A structure describing the private information for a uio device.
  */
@@ -69,8 +54,6 @@ struct rte_uio_pci_dev {
        struct pci_dev *pdev;
        spinlock_t lock; /* spinlock for accessing PCI config space or msix 
data in multi tasks/isr */
        enum rte_intr_mode mode;
-       struct msix_entry \
-               msix_entries[IGBUIO_NUM_MSI_VECTORS]; /* pointer to the msix 
vectors to be allocated later */
 };

 static char *intr_mode = NULL;
@@ -546,6 +529,7 @@ static int
 igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
        struct rte_uio_pci_dev *udev;
+       struct msix_entry msix_entry;

        udev = kzalloc(sizeof(struct rte_uio_pci_dev), GFP_KERNEL);
        if (!udev)
@@ -602,12 +586,8 @@ igbuio_pci_probe(struct pci_dev *dev, co

        /* check if it need to try msix first */
        if (igbuio_intr_mode_preferred == RTE_INTR_MODE_MSIX) {
-               int vector;
-
-               for (vector = 0; vector < IGBUIO_NUM_MSI_VECTORS; vector ++)
-                       udev->msix_entries[vector].entry = vector;
-
-               if (pci_enable_msix(udev->pdev, udev->msix_entries, 
IGBUIO_NUM_MSI_VECTORS) == 0) {
+               msix_entry.entry = 0;
+               if (pci_enable_msix(dev, &msix_entry, 1) == 0) {
                        udev->mode = RTE_INTR_MODE_MSIX;
                }
                else {
@@ -618,7 +598,7 @@ igbuio_pci_probe(struct pci_dev *dev, co
        switch (udev->mode) {
        case RTE_INTR_MODE_MSIX:
                udev->info.irq_flags = 0;
-               udev->info.irq = udev->msix_entries[0].vector;
+               udev->info.irq = msix_entry.vector;
                break;
        case RTE_INTR_MODE_MSI:
                break;