Re: [libvirt] [PATCH] numa: avoid failure in nodememstats on non-NUMA systems

Looks good to me. On 09/22/2017 04:12 PM, Viktor Mihajlovski wrote: > libvirt reports a fake NUMA topology in virConnectGetCapabilities > even if built without numactl support. The fake NUMA topology consists > of a single cell representing the host's cpu and memory resources. > Currently this is the case for ARM and s390[x] RPM builds. > > A client iterating over NUMA cells obtained via virConnectGetCapabilities > and invoking virNodeGetMemoryStats on them will see an internal failure > "NUMA isn't available on this host". An example for such a client is > VDSM. > > Since the intention seems to be that libvirt always reports at least > a single cell it is necessary to return "fake" node memory statistics > matching the previously reported fake cell in case NUMA isn't supported > on the system. > > Signed-off-by: Viktor Mihajlovski <mihajlov(a)linux.vnet.ibm.com&gt; > --- >   src/util/virhostmem.c | 8 ++++++++ >   1 file changed, 8 insertions(+) > > diff --git a/src/util/virhostmem.c b/src/util/virhostmem.c > index a9ba278..fa04a37 100644 > --- a/src/util/virhostmem.c > +++ b/src/util/virhostmem.c > @@ -267,6 +267,14 @@ virHostMemGetStats(int cellNum ATTRIBUTE_UNUSED, >           FILE *meminfo; >           int max_node; > > +        /* > +         * Even if built without numactl, libvirt claims > +         * to have a one-cells NUMA topology. In such a > +         * case return the statistics for the entire host. > +         */ > +        if (!virNumaIsAvailable() && cellNum == 0) > +            cellNum = VIR_NODE_MEMORY_STATS_ALL_CELLS; > + >           if (cellNum == VIR_NODE_MEMORY_STATS_ALL_CELLS) { >               if (VIR_STRDUP(meminfo_path, MEMINFO_PATH) < 0) >                   return -1; >