[dpdk-dev] [PATCH v11 05/13] eal/linux: add interrupt vectors handling on VFIO

[Cunming Liang]

This patch does below:
 - Create VFIO eventfds for each interrupt vector (move to next)
 - Assign per interrupt vector's eventfd to VFIO by ioctl

Signed-off-by: Danny Zhou <danny.zhou at intel.com>
Signed-off-by: Cunming Liang <cunming.liang at intel.com>
---
v8 changes
 - move eventfd creation out of the setup_interrupts to a standalone function

v7 changes
 - cleanup unnecessary code change
 - split event and intr operation to other patches

 lib/librte_eal/linuxapp/eal/eal_interrupts.c | 50 ++++++++--------------------
 1 file changed, 13 insertions(+), 37 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal_interrupts.c 
b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
index 4499055..1dfead5 100644
--- a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
+++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
@@ -128,6 +128,9 @@ static pthread_t intr_thread;
 #ifdef VFIO_PRESENT

 #define IRQ_SET_BUF_LEN  (sizeof(struct vfio_irq_set) + sizeof(int))
+/* irq set buffer length for queue interrupts and LSC interrupt */
+#define MSIX_IRQ_SET_BUF_LEN (sizeof(struct vfio_irq_set) + \
+                             sizeof(int) * (RTE_MAX_RXTX_INTR_VEC_ID + 1))

 /* enable legacy (INTx) interrupts */
 static int
@@ -245,23 +248,6 @@ vfio_enable_msi(struct rte_intr_handle *intr_handle) {
                                                intr_handle->fd);
                return -1;
        }
-
-       /* manually trigger interrupt to enable it */
-       memset(irq_set, 0, len);
-       len = sizeof(struct vfio_irq_set);
-       irq_set->argsz = len;
-       irq_set->count = 1;
-       irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
-       irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;
-       irq_set->start = 0;
-
-       ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
-       if (ret) {
-               RTE_LOG(ERR, EAL, "Error triggering MSI interrupts for fd %d\n",
-                                               intr_handle->fd);
-               return -1;
-       }
        return 0;
 }

@@ -294,7 +280,7 @@ vfio_disable_msi(struct rte_intr_handle *intr_handle) {
 static int
 vfio_enable_msix(struct rte_intr_handle *intr_handle) {
        int len, ret;
-       char irq_set_buf[IRQ_SET_BUF_LEN];
+       char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
        struct vfio_irq_set *irq_set;
        int *fd_ptr;

@@ -302,12 +288,18 @@ vfio_enable_msix(struct rte_intr_handle *intr_handle) {

        irq_set = (struct vfio_irq_set *) irq_set_buf;
        irq_set->argsz = len;
-       irq_set->count = 1;
+       if (!intr_handle->max_intr)
+               intr_handle->max_intr = 1;
+       else if (intr_handle->max_intr > RTE_MAX_RXTX_INTR_VEC_ID)
+               intr_handle->max_intr = RTE_MAX_RXTX_INTR_VEC_ID + 1;
+
+       irq_set->count = intr_handle->max_intr;
        irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | 
VFIO_IRQ_SET_ACTION_TRIGGER;
        irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
        irq_set->start = 0;
        fd_ptr = (int *) &irq_set->data;
-       *fd_ptr = intr_handle->fd;
+       memcpy(fd_ptr, intr_handle->efds, sizeof(intr_handle->efds));
+       fd_ptr[intr_handle->max_intr - 1] = intr_handle->fd;

        ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);

@@ -317,22 +309,6 @@ vfio_enable_msix(struct rte_intr_handle *intr_handle) {
                return -1;
        }

-       /* manually trigger interrupt to enable it */
-       memset(irq_set, 0, len);
-       len = sizeof(struct vfio_irq_set);
-       irq_set->argsz = len;
-       irq_set->count = 1;
-       irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
-       irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
-       irq_set->start = 0;
-
-       ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
-       if (ret) {
-               RTE_LOG(ERR, EAL, "Error triggering MSI-X interrupts for fd 
%d\n",
-                                               intr_handle->fd);
-               return -1;
-       }
        return 0;
 }

@@ -340,7 +316,7 @@ vfio_enable_msix(struct rte_intr_handle *intr_handle) {
 static int
 vfio_disable_msix(struct rte_intr_handle *intr_handle) {
        struct vfio_irq_set *irq_set;
-       char irq_set_buf[IRQ_SET_BUF_LEN];
+       char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
        int len, ret;

        len = sizeof(struct vfio_irq_set);
-- 
1.8.1.4