On Wed, Sep 16, 2020 at 11:04:58 +0800, Zhenyu Zheng wrote:
> Modify virCPUarmCompare in cpu_arm.c to perform compare action.
> This patch only adds host to host CPU compare, the rest cases
> remains the same. This is useful for source and destination host
> compare during migrations to avoid migration between different
> CPU models that have different CPU freatures.
>
> Signed-off-by: Zhenyu Zheng <zheng.zhenyu@xxxxxxxxxxx>
> ---
> src/cpu/cpu_arm.c | 51 +++++++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 47 insertions(+), 4 deletions(-)
>
> diff --git a/src/cpu/cpu_arm.c b/src/cpu/cpu_arm.c
> index 939a3b8390..e8581ec31f 100644
> --- a/src/cpu/cpu_arm.c
> +++ b/src/cpu/cpu_arm.c
> @@ -463,11 +463,54 @@ virCPUarmBaseline(virCPUDefPtr *cpus,
> }
>
> static virCPUCompareResult
> -virCPUarmCompare(virCPUDefPtr host G_GNUC_UNUSED,
> - virCPUDefPtr cpu G_GNUC_UNUSED,
> - bool failMessages G_GNUC_UNUSED)
> +virCPUarmCompare(virCPUDefPtr host,
> + virCPUDefPtr cpu,
> + bool failIncompatible
> +)
> {
> - return VIR_CPU_COMPARE_IDENTICAL;
> + g_autofree char *message = NULL;
> + virCPUCompareResult ret = VIR_CPU_COMPARE_IDENTICAL;
> +
> + /* Only support host to host CPU compare for ARM*/
> + if (cpu->type != VIR_CPU_TYPE_HOST)
> + return ret;
> +
> + if (!host || !host->model) {
> + if (failIncompatible) {
> + virReportError(VIR_ERR_CPU_INCOMPATIBLE, "%s",
> + _("unknown host CPU"));
> + ret = VIR_CPU_COMPARE_ERROR;
> + } else {
> + VIR_WARN("unknown host CPU");
> + ret = VIR_CPU_COMPARE_INCOMPATIBLE;
> + }
> + return ret;
> + }
> +
> + /* Compare vendor and model to check if CPUs are identical */
> + if (STRNEQ(host->vendor, cpu->vendor) ||
> + STRNEQ(host->model, cpu->model)) {
> + VIR_DEBUG("host CPU model does not match required CPU model %s",
> + cpu->model);
> + if (message) {
'message' was initialized to NULL here so this code won't ever be
executed.
> + message = g_strdup_printf(_("host CPU model does not match required "
> + "CPU model %s"),
> + cpu->model);
> + }
> +
> + ret = VIR_CPU_COMPARE_INCOMPATIBLE;
> + }
> +
> + if (failIncompatible && ret == VIR_CPU_COMPARE_INCOMPATIBLE) {
> + ret = VIR_CPU_COMPARE_ERROR;
> + if (message) {
> + virReportError(VIR_ERR_CPU_INCOMPATIBLE, "%s", message);
Neither this code since it will still be NULL.
Also please don't store the error message in a random variable, but
rather use a specific virReportError call. If you want to omit it in
certain cases, just skip the whole virReportError call.
> + } else {
> + virReportError(VIR_ERR_CPU_INCOMPATIBLE, NULL);
> + }
> + }
> +
> + return ret;
> }
>
> static int
> --
> 2.20.1
>
>
