Re: [Qemu-devel] How many msi-x vectors should be allocated for the virtio-serial device?

[Michael S. Tsirkin]

> >From fddf3136cc2cd0372c52a09424715b15c6ad131f Mon Sep 17 00:00:00 2001
> From: Gal Hammer <address@hidden>
> Date: Wed, 27 Feb 2013 15:15:31 +0200
> Subject: [PATCH] Set virtio-serial device to have a default of 2 MSI vectors.
> 
> The virtio-serial device is expected to use 2 MSI vectors, one for
> control queue and a second shared for all queues.
> 
> Signed-off-by: Gal Hammer <address@hidden>

Thanks, applied.

> ---
>  hw/pc.h         | 5 +++++
>  hw/virtio-pci.c | 5 ++++-
>  2 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/pc.h b/hw/pc.h
> index da1b102..f2c1b1c 100644
> --- a/hw/pc.h
> +++ b/hw/pc.h
> @@ -216,6 +216,11 @@ int e820_add_entry(uint64_t, uint64_t, uint32_t);
>              .driver   = "virtio-blk-pci",\
>              .property = "discard_granularity",\
>              .value    = stringify(0),\
> +     },{\
> +            .driver   = "virtio-serial-pci",\
> +            .property = "vectors",\
> +            /* DEV_NVECTORS_UNSPECIFIED as a uint32_t string */\
> +            .value    = stringify(0xFFFFFFFF),\
>       }
>  
>  #endif
> diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
> index a869f53..ba56ab2 100644
> --- a/hw/virtio-pci.c
> +++ b/hw/virtio-pci.c
> @@ -975,6 +975,9 @@ static int virtio_serial_init_pci(PCIDevice *pci_dev)
>      if (!vdev) {
>          return -1;
>      }
> +
> +    /* backwards-compatibility with machines that were created with
> +       DEV_NVECTORS_UNSPECIFIED */
>      vdev->nvectors = proxy->nvectors == DEV_NVECTORS_UNSPECIFIED
>                                          ? proxy->serial.max_virtserial_ports 
> + 1
>                                          : proxy->nvectors;
> @@ -1155,7 +1158,7 @@ static const TypeInfo virtio_net_info = {
>  
>  static Property virtio_serial_properties[] = {
>      DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags, 
> VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
> -    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, 
> DEV_NVECTORS_UNSPECIFIED),
> +    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, 2),
>      DEFINE_PROP_HEX32("class", VirtIOPCIProxy, class_code, 0),
>      DEFINE_VIRTIO_COMMON_FEATURES(VirtIOPCIProxy, host_features),
>      DEFINE_PROP_UINT32("max_ports", VirtIOPCIProxy, 
> serial.max_virtserial_ports, 31),
> -- 
> 1.8.1.2
>