Re: [Qemu-devel] [PATCH v2 10/24] numa: mirror cpu to node mapping in MachineState::possible_cpus

[Igor Mammedov <imammedo@redhat.com>]

On Thu, 4 May 2017 13:40:18 +0200
Andrew Jones <drjones@redhat.com> wrote:

> On Wed, May 03, 2017 at 02:57:04PM +0200, Igor Mammedov wrote:
> > Introduce machine_set_cpu_numa_node() helper that stores
> > node mapping for CPU in MachineState::possible_cpus.
> > CPU and node it belongs to is specified by 'props' argument.
> > 
> > Patch doesn't remove old way of storing mapping in
> > numa_info[X].node_cpu as removing it at the same time
> > makes patch rather big. Instead it just mirrors mapping
> > in possible_cpus and follow up per target patches will
> > switch to possible_cpus and numa_info[X].node_cpu will
> > be removed once there isn't any users left.
> > 
> > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> > ---
> >  include/hw/boards.h |  2 ++
> >  hw/core/machine.c   | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  numa.c              |  8 +++++++
> >  3 files changed, 78 insertions(+)
> > 
> > diff --git a/include/hw/boards.h b/include/hw/boards.h
> > index 5d6af21..1f518a1 100644
> > --- a/include/hw/boards.h
> > +++ b/include/hw/boards.h
> > @@ -42,6 +42,8 @@ bool machine_dump_guest_core(MachineState *machine);
> >  bool machine_mem_merge(MachineState *machine);
> >  void machine_register_compat_props(MachineState *machine);
> >  HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine);
> > +void machine_set_cpu_numa_node(MachineState *machine,
> > +                               CpuInstanceProperties *props, Error **errp);
> >  
> >  /**
> >   * CPUArchId:
> > diff --git a/hw/core/machine.c b/hw/core/machine.c
> > index ada9eea..a63f17b 100644
> > --- a/hw/core/machine.c
> > +++ b/hw/core/machine.c
> > @@ -388,6 +388,74 @@ HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine)
> >      return head;
> >  }
> >  
> > +void machine_set_cpu_numa_node(MachineState *machine,
> > +                               CpuInstanceProperties *props, Error **errp)
> > +{
> > +    MachineClass *mc = MACHINE_GET_CLASS(machine);
> > +    bool match = false;
> > +    int i;
> > +
> > +    if (!mc->possible_cpu_arch_ids) {
> > +        error_setg(errp, "mapping of CPUs to NUMA node is not supported");
> > +        return;
> > +    }
> > +
> > +    /* force board to initialize possible_cpus if it hasn't been done yet */
> > +    mc->possible_cpu_arch_ids(machine);
> > +
> > +    for (i = 0; i < machine->possible_cpus->len; i++) {
> > +        CPUArchId *slot = &machine->possible_cpus->cpus[i];
> > +
> > +        /* reject unsupported by board properties */
> > +        if (props->has_thread_id && !slot->props.has_thread_id) {
> > +            error_setg(errp, "thread-id is not supported");
> > +            return;
> > +        }
> > +
> > +        if (props->has_core_id && !slot->props.has_core_id) {
> > +            error_setg(errp, "core-id is not supported");
> > +            return;
> > +        }
> > +
> > +        if (props->has_socket_id && !slot->props.has_socket_id) {
> > +            error_setg(errp, "socket-id is not supported");
> > +            return;
> > +        }
> > +
> > +        /* skip slots with explicit mismatch */
> > +        if (props->has_thread_id && props->thread_id != slot->props.thread_id) {
> > +                continue;
> > +        }
> > +
> > +        if (props->has_core_id && props->core_id != slot->props.core_id) {
> > +                continue;
> > +        }
> > +
> > +        if (props->has_socket_id && props->socket_id != slot->props.socket_id) {
> > +                continue;
> > +        }  
> 
> nit: above 3 if-conditions could be condensed into 1 compound condition
I'll merge them on the respin

> 
> > +
> > +        /* reject assignment if slot is already assigned, for compatibility
> > +         * of legacy cpu_index mapping with SPAPR core based mapping do not
> > +         * error out if cpu thread and matched core have the same node-id */
> > +        if (slot->props.has_node_id &&
> > +            slot->props.node_id != props->node_id) {
> > +            error_setg(errp, "CPU is already assigned to node-id: %" PRId64,
> > +                       slot->props.node_id);
> > +            return;
> > +        }
> > +
> > +        /* assign slot to node as it's matched '-numa cpu' key */
> > +        match = true;
> > +        slot->props.node_id = props->node_id;
> > +        slot->props.has_node_id = props->has_node_id;
> > +    }
> > +
> > +    if (!match) {
> > +        error_setg(errp, "no match found");
> > +    }
> > +}
> > +
> >  static void machine_class_init(ObjectClass *oc, void *data)
> >  {
> >      MachineClass *mc = MACHINE_CLASS(oc);
> > diff --git a/numa.c b/numa.c
> > index b517870..5ff1212 100644
> > --- a/numa.c
> > +++ b/numa.c
> > @@ -169,6 +169,7 @@ static void numa_node_parse(MachineState *ms, NumaNodeOptions *node,
> >          exit(1);
> >      }
> >      for (cpus = node->cpus; cpus; cpus = cpus->next) {
> > +        CpuInstanceProperties props;
> >          if (cpus->value >= max_cpus) {
> >              error_setg(errp,
> >                         "CPU index (%" PRIu16 ")"
> > @@ -177,6 +178,10 @@ static void numa_node_parse(MachineState *ms, NumaNodeOptions *node,
> >              return;
> >          }
> >          bitmap_set(numa_info[nodenr].node_cpu, cpus->value, 1);
> > +        props = mc->cpu_index_to_instance_props(ms, cpus->value);
> > +        props.node_id = nodenr;
> > +        props.has_node_id = true;
> > +        machine_set_cpu_numa_node(ms, &props, &error_fatal);
> >      }
> >  
> >      if (node->has_mem && node->has_memdev) {
> > @@ -393,9 +398,12 @@ void parse_numa_opts(MachineState *ms)
> >          if (i == nb_numa_nodes) {
> >              for (i = 0; i < max_cpus; i++) {
> >                  CpuInstanceProperties props;
> > +                /* fetch default mapping from board and enable it */
> >                  props = mc->cpu_index_to_instance_props(ms, i);
> > +                props.has_node_id = true;
> >  
> >                  set_bit(i, numa_info[props.node_id].node_cpu);
> > +                machine_set_cpu_numa_node(ms, &props, &error_fatal);
> >              }
> >          }
> >  
> > -- 
> > 2.7.4
> >  
> 
> Reviewed-by: Andrew Jones <drjones@redhat.com>