On Wed, 11 Dec 2013 13:19:21 +0100
Paolo Bonzini <pbonz...@redhat.com> wrote:
> This option provides the infrastructure for binding guest NUMA nodes
> to host NUMA nodes. For example:
>
> -object memory-ram,size=1024M,policy=membind,host-nodes=0,id=ram-node0 \
> -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
> -object memory-ram,size=1024M,policy=interleave,host-nodes=1-3,id=ram-node1 \
> -numa node,nodeid=1,cpus=1,memdev=ram-node1
I was thinking about a bit more radical change:
-object memory-ram,size=1024M,policy=membind,host-nodes=0,id=ram-node0
-device dimm,memdev=ram-node0,node=0
-object memory-ram,size=1024M,policy=membind,host-nodes=1,id=ram-node1
-device dimm,memdev=ram-node1,node=1
that would allow to avoid synthetic -numa option but would require conversion
of initial RAM to dimms. That would be more flexible for example allowing
bind several backends to one node (like: 1Gb_hugepage + 2Mb_hugepage ones)
>
> The option replaces "-numa mem".
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> include/sysemu/sysemu.h | 2 ++
> numa.c | 64
> +++++++++++++++++++++++++++++++++++++++++++++++--
> qapi-schema.json | 6 ++++-
> 3 files changed, 69 insertions(+), 3 deletions(-)
>
> diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
> index e9da760..acfc0c7 100644
> --- a/include/sysemu/sysemu.h
> +++ b/include/sysemu/sysemu.h
> @@ -12,6 +12,7 @@
> #include "qemu/bitmap.h"
> #include "qom/object.h"
> #include "hw/boards.h"
> +#include "sysemu/hostmem.h"
>
> /* vl.c */
>
> @@ -140,6 +141,7 @@ extern int nb_numa_nodes;
> typedef struct node_info {
> uint64_t node_mem;
> DECLARE_BITMAP(node_cpu, MAX_CPUMASK_BITS);
> + HostMemoryBackend *node_memdev;
> } NodeInfo;
> extern NodeInfo numa_info[MAX_NODES];
> void set_numa_nodes(void);
> diff --git a/numa.c b/numa.c
> index f903b9e..686dbfa 100644
> --- a/numa.c
> +++ b/numa.c
> @@ -27,6 +27,8 @@
> #include "qapi-visit.h"
> #include "qapi/opts-visitor.h"
> #include "qapi/dealloc-visitor.h"
> +#include "qapi/qmp/qerror.h"
> +
> QemuOptsList qemu_numa_opts = {
> .name = "numa",
> .implied_opt_name = "type",
> @@ -34,10 +36,13 @@ QemuOptsList qemu_numa_opts = {
> .desc = { { 0 } } /* validated with OptsVisitor */
> };
>
> +static int have_memdevs = -1;
> +
> static int numa_node_parse(NumaNodeOptions *opts)
> {
> uint16_t nodenr;
> uint16List *cpus = NULL;
> + Error *local_err = NULL;
>
> if (opts->has_nodeid) {
> nodenr = opts->nodeid;
> @@ -60,6 +65,19 @@ static int numa_node_parse(NumaNodeOptions *opts)
> bitmap_set(numa_info[nodenr].node_cpu, cpus->value, 1);
> }
>
> + if (opts->has_mem && opts->has_memdev) {
> + fprintf(stderr, "qemu: cannot specify both mem= and memdev=\n");
> + return -1;
> + }
> +
> + if (have_memdevs == -1) {
> + have_memdevs = opts->has_memdev;
> + }
> + if (opts->has_memdev != have_memdevs) {
> + fprintf(stderr, "qemu: memdev option must be specified for either "
> + "all or no nodes\n");
> + }
> +
> if (opts->has_mem) {
> int64_t mem_size;
> char *endptr;
> @@ -70,7 +88,19 @@ static int numa_node_parse(NumaNodeOptions *opts)
> }
> numa_info[nodenr].node_mem = mem_size;
> }
> + if (opts->has_memdev) {
> + Object *o;
> + o = object_resolve_path_type(opts->memdev, TYPE_MEMORY_BACKEND,
> NULL);
> + if (!o) {
> + error_setg(&local_err, "memdev=%s is ambiguous", opts->memdev);
> + qerror_report_err(local_err);
> + return -1;
> + }
>
> + object_ref(o);
> + numa_info[nodenr].node_mem = object_property_get_int(o, "size",
> NULL);
> + numa_info[nodenr].node_memdev = MEMORY_BACKEND(o);
> + }
there wouldn't be any need for keeping numa mappings in separate structure,
if we use node property of dimm device.
acpi_build then could build SRAT directly enumerating present dimm devices.
> return 0;
> }
>
> @@ -188,12 +218,42 @@ void set_numa_modes(void)
> }
> }
>
> +static void allocate_system_memory_nonnuma(MemoryRegion *mr, Object *owner,
> + const char *name,
> + QEMUMachineInitArgs *args)
> +{
> + uint64_t ram_size = args->ram_size;
> +
> + memory_region_init_ram(mr, owner, name, ram_size);
> + vmstate_register_ram_global(mr);
> +}
> +
> void memory_region_allocate_system_memory(MemoryRegion *mr, Object *owner,
> const char *name,
> QEMUMachineInitArgs *args)
> {
> uint64_t ram_size = args->ram_size;
> + uint64_t addr = 0;
> + int i;
>
> - memory_region_init_ram(mr, owner, name, ram_size);
> - vmstate_register_ram_global(mr);
> + if (nb_numa_nodes == 0 || !have_memdevs) {
> + allocate_system_memory_nonnuma(mr, owner, name, args);
> + return;
> + }
> +
> + memory_region_init(mr, owner, name, ram_size);
container might clip subregions due to presence of hole,
it's size should be ram_size + hole_size.
> + for (i = 0; i < nb_numa_nodes; i++) {
> + Error *local_err = NULL;
> + uint64_t size = numa_info[i].node_mem;
> + HostMemoryBackend *backend = numa_info[i].node_memdev;
> + MemoryRegion *seg = host_memory_backend_get_memory(backend,
> &local_err);
> + if (local_err) {
> + qerror_report_err(local_err);
> + exit(1);
> + }
> +
> + memory_region_add_subregion(mr, addr, seg);
> + vmstate_register_ram_global(seg);
> + addr += size;
> + }
> }
> diff --git a/qapi-schema.json b/qapi-schema.json
> index d99e39d..e449316 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -4256,7 +4256,10 @@
> #
> # @cpus: #optional VCPUs belong to this node
> #
> -# @mem: #optional memory size of this node
> +# @memdev: #optional memory backend object. If specified for one node,
> +# it must be specified for all nodes.
> +#
> +# @mem: #optional memory size of this node; mutually exclusive with @memdev.
> #
> # Since: 2.0
> ##
> @@ -4264,4 +4267,5 @@
> 'data': {
> '*nodeid': 'uint16',
> '*cpus': ['uint16'],
> + '*memdev': 'str',
> '*mem': 'str' }}
> --
> 1.8.4.2
>
--
Regards,
Igor
