[libvirt] [PATCH 2/4] conf: Move hugepage XML validation check out of qemu_command

[Michal Privoznik]

On 07/11/2018 10:22 AM, Pavel Hrdina wrote:
> We can safely validate the hugepage nodeset attribute at a define time.
> This validation is not done for already existing domains when the daemon
> is restarted.
> 
> All the changes to the tests are necessary because we move the error
> from domain start into XML parse.
> 
> Signed-off-by: Pavel Hrdina <phrdina at redhat.com>
> ---
>  src/conf/domain_conf.c                        | 32 +++++++++++++++++
>  src/qemu/qemu_command.c                       | 34 -------------------
>  .../seclabel-dynamic-none-relabel.xml         |  2 +-
>  tests/qemuxml2argvtest.c                      | 16 +++++----
>  .../qemuxml2xmloutdata/hugepages-pages10.xml  | 30 ----------------
>  tests/qemuxml2xmloutdata/hugepages-pages4.xml |  1 -
>  tests/qemuxml2xmloutdata/hugepages-pages9.xml | 31 -----------------
>  .../seclabel-dynamic-none-relabel.xml         |  2 +-
>  tests/qemuxml2xmltest.c                       |  3 --
>  9 files changed, 43 insertions(+), 108 deletions(-)
>  delete mode 100644 tests/qemuxml2xmloutdata/hugepages-pages10.xml
>  delete mode 120000 tests/qemuxml2xmloutdata/hugepages-pages4.xml
>  delete mode 100644 tests/qemuxml2xmloutdata/hugepages-pages9.xml
> 
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 7396616eda..20d67e7854 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -6104,6 +6104,35 @@ virDomainDefLifecycleActionValidate(const virDomainDef *def)
>  }
>  
>  
> +static int
> +virDomainDefMemtuneValidate(const virDomainDef *def)
> +{
> +    const virDomainMemtune *mem = &(def->mem);
> +    size_t i;
> +    ssize_t pos = virDomainNumaGetNodeCount(def->numa) - 1;
> +
> +    for (i = 0; i < mem->nhugepages; i++) {
> +        ssize_t nextBit;
> +
> +        if (!mem->hugepages[i].nodemask) {
> +            /* This is the master hugepage to use. Skip it as it has no
> +             * nodemask anyway. */
> +            continue;
> +        }
> +
> +        nextBit = virBitmapNextSetBit(mem->hugepages[i].nodemask, pos);
> +        if (nextBit >= 0) {

I think its fair to enable hugepages for node #0 which is always there
(even if not configured in domain XML). Just try to run 'numactl -H'
from a domain that has no <numa/> in its XML.

> +            virReportError(VIR_ERR_XML_DETAIL,
> +                           _("hugepages: node %zd not found"),
> +                           nextBit);
> +            return -1;
> +        }
> +    }

Also, I see that you're removing hugepages-pages9 test from xml2xml
test. But that is needed only because you disallowed nodeset='0' for
nonnuma domain. The real problem there is that the default page size has
no numa node to apply to, not nodeset='0'. I guess we need to check for
that too (or do we want to?)

> +
> +    return 0;
> +}
> +

Michal