On 11/22/2017 04:45 AM, Michal Privoznik wrote:
On 11/22/2017 01:04 AM, John Ferlan wrote:
On 11/14/2017 09:47 AM, Michal Privoznik wrote:
Since we already have such support for libxl all we need is qemu driver adjustment. And a test case.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_command.c | 36 +++++++++++- .../qemuxml2argv-numatune-distances.args | 63 +++++++++++++++++++++ .../qemuxml2argv-numatune-distances.xml | 65 ++++++++++++++++++++++ tests/qemuxml2argvtest.c | 2 + 4 files changed, 165 insertions(+), 1 deletion(-) create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-numatune-distances.args create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-numatune-distances.xml
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index eb72db33b..8b9daaea3 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -7675,7 +7675,7 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg, virCommandPtr cmd, qemuDomainObjPrivatePtr priv) { - size_t i; + size_t i, j; virQEMUCapsPtr qemuCaps = priv->qemuCaps; virBuffer buf = VIR_BUFFER_INITIALIZER; char *cpumask = NULL, *tmpmask = NULL, *next = NULL; @@ -7685,6 +7685,7 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg, int ret = -1; size_t ncells = virDomainNumaGetNodeCount(def->numa); const long system_page_size = virGetSystemPageSizeKB(); + bool numa_distances = false;
if (virDomainNumatuneHasPerNodeBinding(def->numa) && !(virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_RAM) || @@ -7793,6 +7794,39 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
virCommandAddArgBuffer(cmd, &buf); } + + /* If NUMA node distance is specified for at least one pair + * of nodes, we have to specify all the distances. Even + * though they might be the default ones. */ + for (i = 0; i < ncells; i++) { + for (j = 0; j < ncells; j++) { + if (!virDomainNumaNodeDistanceSpecified(def->numa, i, j)) + continue; + + numa_distances = true; + + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_NUMA_DIST)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("setting NUMA distances is not " + "supported with this qemu")); + goto cleanup; + } + } + }
Not sure I understand the need for the above double loop.... Even with your adjustment...
It would seem that all that's necessary is
for (i < 0; i < ncells; i++) { if (numa->mem_nodes[i].ndistances > 0)
It things only were so simple. Thing is, numa is a private struct. We need accessors for getting any value. I can't just dereference numa struct from qemu code.
Oh right... Could have another accessor too, but your need is a bit more specific especially since as you point out next qemu will default to 10 and 20... Still I think with the different name this will make more sense in v2.
That's why I'm introducing an accessor in 2/5. Moreover, in case all values are defaults I wanted to not put them onto the cmd line. The advantage would be that it would work even with older qemu which doesn't have the capability. I mean, qemu does follow the spec and if no distances are provided it uses the ones from the spec (10 and 20).
Nothing is ever so simple, but I did ask if I was in the weeds too basically because I've learned over time that simplicity and numa are not synonymous! John