[libvirt] Problem of host CPU topology parsing

Hi, We have problem of host CPU topology parsing on special platforms (general platforms are fine). E.g. On a AMD machine with 48 CPUs [1] (4 sockets, 6 cores indeed [2]), VIR_NODEINFO_MAXCPUS [3] will always return 24 as the total CPU number. As a result, a domain without "cpuset" or "placement='auto'" (which drives numad) will only be pinned to part of the host CPUs (in the case of the 48 CPUS AMD machine, domain process will be pinned to only the first 24 CPUs), which cause the performance lost. And actually it's also functional bug, as the "cpuset" specified by user could be truncated. If a domain uses "placement='auto'", and the advisory nodeset returned from numad has node(s) exceeds the wrong max CPU number, the domain will fail to start, as the bitmask passed to sched_setaffinity is fully filled with zero. "nodeinfo.cpus" has the right number though, but I'm not sure if it should be used as the max CPU number. VIR_NODEINFO_MAXCPUS is used in many places, and I'd never want to fix something here, but break other things there. Anyone has thought on how to sort the fucky topology out? [1] http://fpaste.org/MTtz/ [2] http://fpaste.org/mtoA/, http://fpaste.org/EPLd/ [3] #define VIR_NODEINFO_MAXCPUS(nodeinfo) ((nodeinfo).nodes*(nodeinfo).sockets*(nodeinfo).cores*(nodeinfo).threads) Regards, Osier