[libvirt PATCH v4 3/3] add virQEMUCapsProbeQMPTCGState function to set QEMU_CAPS_TCG_DISABLED

[Peter Krempa]

On Wed, Apr 22, 2020 at 17:50:44 -0400, Tobin Feldman-Fitzthum wrote:
> Add virQEMUCapsProbeQMPTCGState to set TCG_DISABLED cap if version 
> is > 2.10, KVM is enabled, and tcg-accel is not present in 
> qom-list-types result.
> 
> Signed-off-by: Tobin Feldman-Fitzthum <tobin at linux.vnet.ibm.com>
> ---
>  src/qemu/qemu_capabilities.c | 34 ++++++++++++++++++++++++++++++++--
>  1 file changed, 32 insertions(+), 2 deletions(-)

I don't feel comfortable reviewing the other two patches which deal with
the actual use of the capability, so I'll leave those for somebody else.

> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
> index e7179ea048..4a3170fc5c 100644
> --- a/src/qemu/qemu_capabilities.c
> +++ b/src/qemu/qemu_capabilities.c
> @@ -2576,7 +2576,35 @@ virQEMUCapsProbeQMPGenericProps(virQEMUCapsPtr qemuCaps,
>  }
>  
>  static int
> -virQEMUCapsProbeQMPDevices(virQEMUCapsPtr qemuCaps,
> +virQEMUCapsProbeQMPTCGState(virQEMUCapsPtr qemuCaps,

Returned value of the new function is not used, so please define it as
'void'

> +                            char **values,
> +                            int nvalues)
> +{
> +    size_t i;
> +    bool found = false;
> +    /*
> +     * As of version 2.10, QEMU can be built without the TCG.
> +     * */
> +    if (qemuCaps->version < 2010000)
> +        return 0;
> +    if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_KVM))
> +        return 0;
> +
> +    for (i = 0; i < nvalues; i++) {
> +        if (STREQ(values[i], "tcg-accel")) {
> +            found = true;

You can set the capability here without intermediate variable and just
return.

> +            break;
> +        }
> +    }
> +
> +    if (!found)
> +        virQEMUCapsSet(qemuCaps, QEMU_CAPS_TCG_DISABLED);
> +
> +    return 0;
> +}
> +
> +static int
> +virQEMUCapsProbeQMPTypes(virQEMUCapsPtr qemuCaps,
>                             qemuMonitorPtr mon)
>  {
>      int nvalues;

With the above resolved:

Reviewed-by: Peter Krempa <pkrempa at redhat.com>