> -----Original Message-----
> From: dev <dev-boun...@dpdk.org> On Behalf Of David Marchand
> Sent: Tuesday, July 2, 2019 6:18 PM
> To: dev@dpdk.org
> Cc: anatoly.bura...@intel.com; alex.william...@redhat.com;
> maxime.coque...@redhat.com; tho...@monjalon.net;
> step...@networkplumber.org
> Subject: [EXT] [dpdk-dev] [RFC PATCH] vfio: move eventfd/interrupt pairing at
> setup time
>
>
> ----------------------------------------------------------------------
> Populating the eventfd in rte_intr_enable in each request to vfio triggers a
> reconfiguration of the interrupt handler on the kernel side.
> The problem is that rte_intr_enable is often used to re-enable masked
> interrupts
> from drivers interrupt handlers.
>
> This reconfiguration leaves a window during which a device could send an
> interrupt and then the kernel logs this unsolicited interrupt:
> [158764.159833] do_IRQ: 9.34 No irq handler for vector
>
> VFIO api makes it possible to set the fd at setup time.
> Make use of this and then we only need to ask for masking/unmasking legacy
> interrupts and we have nothing to do for MSI/MSIX.
>
> "rxtx" interrupts are left untouched but are most likely subject to the same
> issue.
>
> Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=1654824
> Signed-off-by: David Marchand <david.march...@redhat.com>
Thanks David for this patch.
I have tested this patch with FastLinq adapters on which original issue is
reported.
Tested this with MSI-x and legacy interrupt mode.
Tested-by: Shahed Shaikh <shsha...@marvell.com>
> ---
> Sending as a RFC patch since it is not trivial and can eat your babies.
> Could people that know well this parts have a look at this?
> Thanks!
>
> ---
> drivers/bus/pci/linux/pci_vfio.c | 78 ++++++------
> lib/librte_eal/linux/eal/eal_interrupts.c | 197
> +++++++-----------------------
> 2 files changed, 86 insertions(+), 189 deletions(-)
>
> diff --git a/drivers/bus/pci/linux/pci_vfio.c
> b/drivers/bus/pci/linux/pci_vfio.c
> index ebf6ccd..e4c32c4 100644
> --- a/drivers/bus/pci/linux/pci_vfio.c
> +++ b/drivers/bus/pci/linux/pci_vfio.c
> @@ -186,8 +186,11 @@
> static int
> pci_vfio_setup_interrupts(struct rte_pci_device *dev, int vfio_dev_fd) {
> - int i, ret, intr_idx;
> + char irq_set_buf[sizeof(struct vfio_irq_set) + sizeof(int)];
> + struct vfio_irq_set *irq_set;
> enum rte_intr_mode intr_mode;
> + int i, ret, intr_idx;
> + int fd;
>
> /* default to invalid index */
> intr_idx = VFIO_PCI_NUM_IRQS;
> @@ -219,7 +222,6 @@
> /* start from MSI-X interrupt type */
> for (i = VFIO_PCI_MSIX_IRQ_INDEX; i >= 0; i--) {
> struct vfio_irq_info irq = { .argsz = sizeof(irq) };
> - int fd = -1;
>
> /* skip interrupt modes we don't want */
> if (intr_mode != RTE_INTR_MODE_NONE && @@ -235,51
> +237,51 @@
> return -1;
> }
>
> + /* found a usable interrupt mode */
> + if ((irq.flags & VFIO_IRQ_INFO_EVENTFD) != 0)
> + break;
> +
> /* if this vector cannot be used with eventfd, fail if we
> explicitly
> * specified interrupt type, otherwise continue */
> - if ((irq.flags & VFIO_IRQ_INFO_EVENTFD) == 0) {
> - if (intr_mode != RTE_INTR_MODE_NONE) {
> - RTE_LOG(ERR, EAL,
> - " interrupt vector does not
> support eventfd!\n");
> - return -1;
> - } else
> - continue;
> - }
> -
> - /* set up an eventfd for interrupts */
> - fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
> - if (fd < 0) {
> - RTE_LOG(ERR, EAL, " cannot set up eventfd, "
> - "error %i (%s)\n", errno,
> strerror(errno));
> + if (intr_mode != RTE_INTR_MODE_NONE) {
> + RTE_LOG(ERR, EAL, " interrupt vector does not support
> eventfd!\n");
> return -1;
> }
> + }
>
> - dev->intr_handle.fd = fd;
> - dev->intr_handle.vfio_dev_fd = vfio_dev_fd;
> + if (i < 0)
> + return -1;
>
> - switch (i) {
> - case VFIO_PCI_MSIX_IRQ_INDEX:
> - intr_mode = RTE_INTR_MODE_MSIX;
> - dev->intr_handle.type =
> RTE_INTR_HANDLE_VFIO_MSIX;
> - break;
> - case VFIO_PCI_MSI_IRQ_INDEX:
> - intr_mode = RTE_INTR_MODE_MSI;
> - dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSI;
> - break;
> - case VFIO_PCI_INTX_IRQ_INDEX:
> - intr_mode = RTE_INTR_MODE_LEGACY;
> - dev->intr_handle.type =
> RTE_INTR_HANDLE_VFIO_LEGACY;
> - break;
> - default:
> - RTE_LOG(ERR, EAL, " unknown interrupt type!\n");
> - return -1;
> - }
> + fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
> + if (fd < 0) {
> + RTE_LOG(ERR, EAL, " cannot set up eventfd, error %i (%s)\n",
> + errno, strerror(errno));
> + return -1;
> + }
>
> - return 0;
> + irq_set = (struct vfio_irq_set *)irq_set_buf;
> + irq_set->argsz = sizeof(irq_set_buf);
> + irq_set->flags =
> VFIO_IRQ_SET_DATA_EVENTFD|VFIO_IRQ_SET_ACTION_TRIGGER;
> + irq_set->index = i;
> + irq_set->start = 0;
> + irq_set->count = 1;
> + memcpy(&irq_set->data, &fd, sizeof(int));
> + if (ioctl(vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set) < 0) {
> + RTE_LOG(ERR, EAL, " error configuring interrupt\n");
> + close(fd);
> + return -1;
> }
>
> - /* if we're here, we haven't found a suitable interrupt vector */
> - return -1;
> + dev->intr_handle.fd = fd;
> + dev->intr_handle.vfio_dev_fd = vfio_dev_fd;
> + if (i == VFIO_PCI_MSIX_IRQ_INDEX)
> + dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSIX;
> + else if (i == VFIO_PCI_MSI_IRQ_INDEX)
> + dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSI;
> + else if (i == VFIO_PCI_INTX_IRQ_INDEX)
> + dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_LEGACY;
> +
> + return 0;
> }
>
> #ifdef HAVE_VFIO_DEV_REQ_INTERFACE
> diff --git a/lib/librte_eal/linux/eal/eal_interrupts.c
> b/lib/librte_eal/linux/eal/eal_interrupts.c
> index 79ad5e8..27976b3 100644
> --- a/lib/librte_eal/linux/eal/eal_interrupts.c
> +++ b/lib/librte_eal/linux/eal/eal_interrupts.c
> @@ -109,42 +109,19 @@ struct rte_intr_source {
>
> /* enable legacy (INTx) interrupts */
> static int
> -vfio_enable_intx(const struct rte_intr_handle *intr_handle) {
> - struct vfio_irq_set *irq_set;
> - char irq_set_buf[IRQ_SET_BUF_LEN];
> - int len, ret;
> - int *fd_ptr;
> -
> - len = sizeof(irq_set_buf);
> -
> - /* enable INTx */
> - irq_set = (struct vfio_irq_set *) irq_set_buf;
> - irq_set->argsz = len;
> - irq_set->count = 1;
> - irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
> VFIO_IRQ_SET_ACTION_TRIGGER;
> - irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
> - irq_set->start = 0;
> - fd_ptr = (int *) &irq_set->data;
> - *fd_ptr = intr_handle->fd;
> -
> - ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
> -
> - if (ret) {
> - RTE_LOG(ERR, EAL, "Error enabling INTx interrupts for fd
> %d\n",
> - intr_handle->fd);
> - return -1;
> - }
> +vfio_enable_intx(const struct rte_intr_handle *intr_handle) {
> + struct vfio_irq_set irq_set;
> + int ret;
>
> - /* unmask INTx after enabling */
> - 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_UNMASK;
> - irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
> - irq_set->start = 0;
> + /* unmask INTx */
> + irq_set.argsz = sizeof(irq_set);
> + irq_set.flags = VFIO_IRQ_SET_DATA_NONE |
> VFIO_IRQ_SET_ACTION_UNMASK;
> + irq_set.index = VFIO_PCI_INTX_IRQ_INDEX;
> + irq_set.start = 0;
> + irq_set.count = 1;
>
> - ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
> + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, &irq_set);
>
> if (ret) {
> RTE_LOG(ERR, EAL, "Error unmasking INTx interrupts for fd
> %d\n", @@ -156,128 +133,51 @@ struct rte_intr_source {
>
> /* disable legacy (INTx) interrupts */
> static int
> -vfio_disable_intx(const struct rte_intr_handle *intr_handle) {
> - struct vfio_irq_set *irq_set;
> - char irq_set_buf[IRQ_SET_BUF_LEN];
> - int len, ret;
> -
> - len = sizeof(struct vfio_irq_set);
> +vfio_disable_intx(const struct rte_intr_handle *intr_handle) {
> + struct vfio_irq_set irq_set;
> + int ret;
>
> - /* mask interrupts before disabling */
> - irq_set = (struct vfio_irq_set *) irq_set_buf;
> - irq_set->argsz = len;
> - irq_set->count = 1;
> - irq_set->flags = VFIO_IRQ_SET_DATA_NONE |
> VFIO_IRQ_SET_ACTION_MASK;
> - irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
> - irq_set->start = 0;
> + /* mask interrupts */
> + irq_set.argsz = sizeof(irq_set);
> + irq_set.flags = VFIO_IRQ_SET_DATA_NONE |
> VFIO_IRQ_SET_ACTION_MASK;
> + irq_set.index = VFIO_PCI_INTX_IRQ_INDEX;
> + irq_set.start = 0;
> + irq_set.count = 1;
>
> - ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
> + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, &irq_set);
>
> if (ret) {
> RTE_LOG(ERR, EAL, "Error masking INTx interrupts for fd %d\n",
> intr_handle->fd);
> return -1;
> }
> -
> - /* disable INTx*/
> - memset(irq_set, 0, len);
> - irq_set->argsz = len;
> - irq_set->count = 0;
> - irq_set->flags = VFIO_IRQ_SET_DATA_NONE |
> VFIO_IRQ_SET_ACTION_TRIGGER;
> - irq_set->index = VFIO_PCI_INTX_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 disabling INTx interrupts for fd %d\n",
> intr_handle->fd);
> - return -1;
> - }
> - return 0;
> -}
> -
> -/* enable MSI interrupts */
> -static int
> -vfio_enable_msi(const struct rte_intr_handle *intr_handle) {
> - int len, ret;
> - char irq_set_buf[IRQ_SET_BUF_LEN];
> - struct vfio_irq_set *irq_set;
> - int *fd_ptr;
> -
> - len = sizeof(irq_set_buf);
> -
> - irq_set = (struct vfio_irq_set *) irq_set_buf;
> - irq_set->argsz = len;
> - irq_set->count = 1;
> - irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
> VFIO_IRQ_SET_ACTION_TRIGGER;
> - irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;
> - irq_set->start = 0;
> - fd_ptr = (int *) &irq_set->data;
> - *fd_ptr = intr_handle->fd;
> -
> - ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
> -
> - if (ret) {
> - RTE_LOG(ERR, EAL, "Error enabling MSI interrupts for fd %d\n",
> - intr_handle->fd);
> - return -1;
> - }
> return 0;
> }
>
> -/* disable MSI interrupts */
> -static int
> -vfio_disable_msi(const struct rte_intr_handle *intr_handle) {
> - struct vfio_irq_set *irq_set;
> - char irq_set_buf[IRQ_SET_BUF_LEN];
> - int len, ret;
> -
> - len = sizeof(struct vfio_irq_set);
> -
> - irq_set = (struct vfio_irq_set *) irq_set_buf;
> - irq_set->argsz = len;
> - irq_set->count = 0;
> - 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 disabling MSI interrupts for fd %d\n",
> intr_handle->fd);
> -
> - return ret;
> -}
> -
> /* enable MSI-X interrupts */
> static int
> -vfio_enable_msix(const struct rte_intr_handle *intr_handle) {
> - int len, ret;
> +vfio_enable_msix(const struct rte_intr_handle *intr_handle) {
> char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
> struct vfio_irq_set *irq_set;
> - int *fd_ptr;
> + int len, ret;
> +
> + if (intr_handle->nb_efd == 0)
> + return 0;
>
> len = sizeof(irq_set_buf);
>
> irq_set = (struct vfio_irq_set *) irq_set_buf;
> irq_set->argsz = len;
> - /* 0 < irq_set->count < RTE_MAX_RXTX_INTR_VEC_ID + 1 */
> - irq_set->count = intr_handle->max_intr ?
> - (intr_handle->max_intr > RTE_MAX_RXTX_INTR_VEC_ID + 1 ?
> - RTE_MAX_RXTX_INTR_VEC_ID + 1 : intr_handle->max_intr) : 1;
> 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;
> - /* INTR vector offset 0 reserve for non-efds mapping */
> - fd_ptr[RTE_INTR_VEC_ZERO_OFFSET] = intr_handle->fd;
> - memcpy(&fd_ptr[RTE_INTR_VEC_RXTX_OFFSET], intr_handle->efds,
> - sizeof(*intr_handle->efds) * intr_handle->nb_efd);
> + irq_set->start = RTE_INTR_VEC_RXTX_OFFSET;
> + irq_set->count = intr_handle->nb_efd;
> + memcpy(&irq_set->data, intr_handle->efds,
> + sizeof(*intr_handle->efds) * intr_handle->nb_efd);
>
> ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
> -
> if (ret) {
> RTE_LOG(ERR, EAL, "Error enabling MSI-X interrupts for fd
> %d\n",
> intr_handle->fd);
> @@ -289,22 +189,21 @@ struct rte_intr_source {
>
> /* disable MSI-X interrupts */
> static int
> -vfio_disable_msix(const struct rte_intr_handle *intr_handle) {
> - struct vfio_irq_set *irq_set;
> - char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
> - int len, ret;
> -
> - len = sizeof(struct vfio_irq_set);
> +vfio_disable_msix(const struct rte_intr_handle *intr_handle) {
> + struct vfio_irq_set irq_set;
> + int ret;
>
> - irq_set = (struct vfio_irq_set *) irq_set_buf;
> - irq_set->argsz = len;
> - irq_set->count = 0;
> - 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;
> + if (intr_handle->nb_efd == 0)
> + return 0;
>
> - ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
> + irq_set.argsz = sizeof(irq_set);
> + irq_set.flags = VFIO_IRQ_SET_DATA_NONE |
> VFIO_IRQ_SET_ACTION_TRIGGER;
> + irq_set.index = VFIO_PCI_MSIX_IRQ_INDEX;
> + irq_set.start = RTE_INTR_VEC_RXTX_OFFSET;
> + irq_set.count = intr_handle->nb_efd;
>
> + ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, &irq_set);
> if (ret)
> RTE_LOG(ERR, EAL,
> "Error disabling MSI-X interrupts for fd %d\n",
> intr_handle->fd); @@ -665,9 +564,7 @@ struct rte_intr_source {
> return -1;
> break;
> case RTE_INTR_HANDLE_VFIO_MSI:
> - if (vfio_enable_msi(intr_handle))
> - return -1;
> - break;
> + return 0;
> case RTE_INTR_HANDLE_VFIO_LEGACY:
> if (vfio_enable_intx(intr_handle))
> return -1;
> @@ -721,9 +618,7 @@ struct rte_intr_source {
> return -1;
> break;
> case RTE_INTR_HANDLE_VFIO_MSI:
> - if (vfio_disable_msi(intr_handle))
> - return -1;
> - break;
> + return 0;
> case RTE_INTR_HANDLE_VFIO_LEGACY:
> if (vfio_disable_intx(intr_handle))
> return -1;
> --
> 1.8.3.1
