[libvirt] [PATCH v2 3/4] qemu: Add capability for vhost-user multiqueue

[John Ferlan]

On 06/04/2015 01:04 PM, Martin Kletzander wrote:
> The support for this was added in QEMU with commit
> 830d70db692e374b55555f4407f96a1ceefdcc97.  Unfortunately we have to do
> another ugly version-based capability check.  The other option would be
> not to check for the capability at all and leave that to qemu as it's
> doen with multiqueue tap devices.
> 
> Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
> ---
>  src/qemu/qemu_capabilities.c | 6 ++++++
>  src/qemu/qemu_capabilities.h | 1 +
>  2 files changed, 7 insertions(+)
> 

This patch will need some updates because of commit id '29ce1693' which
now takes 189. It's obvious what needs to be done though and doesn't
require sending a new series.

> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
> index 960afa4ac0db..f102ed80f15e 100644
> --- a/src/qemu/qemu_capabilities.c
> +++ b/src/qemu/qemu_capabilities.c
> @@ -284,6 +284,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
>                "aes-key-wrap",
>                "dea-key-wrap",
>                "pci-serial",
> +              "vhost-user-multiq",

This one will add the "/* 190 */"

John
>      );
> 
> 
> @@ -3283,6 +3284,11 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr qemuCaps,
>      if (qemuCaps->version >= 2002000)
>          virQEMUCapsSet(qemuCaps, QEMU_CAPS_MACHINE_VMPORT_OPT);
> 
> +    /* vhost-user supports multi-queue from v2.4.0 onwards,
> +     * but there is no way to query for that capability */
> +    if (qemuCaps->version >= 2004000)
> +        virQEMUCapsSet(qemuCaps, QEMU_CAPS_VHOSTUSER_MULTIQ);
> +
>      if (virQEMUCapsProbeQMPCommands(qemuCaps, mon) < 0)
>          goto cleanup;
>      if (virQEMUCapsProbeQMPEvents(qemuCaps, mon) < 0)
> diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
> index 9c956f3007be..3dbd767f2516 100644
> --- a/src/qemu/qemu_capabilities.h
> +++ b/src/qemu/qemu_capabilities.h
> @@ -228,6 +228,7 @@ typedef enum {
>      QEMU_CAPS_AES_KEY_WRAP       = 186, /* -machine aes_key_wrap */
>      QEMU_CAPS_DEA_KEY_WRAP       = 187, /* -machine dea_key_wrap */
>      QEMU_CAPS_DEVICE_PCI_SERIAL  = 188, /* -device pci-serial */
> +    QEMU_CAPS_VHOSTUSER_MULTIQ   = 189, /* vhost-user with -netdev queues= */
> 
>      QEMU_CAPS_LAST,                   /* this must always be the last item */
>  } virQEMUCapsFlags;
>