numa: Extend CLI to provide initiator information for numa nodes

In ACPI 6.3 chapter 5.2.27 Heterogeneous Memory Attribute Table (HMAT),
The initiator represents processor which access to memory. And in 5.2.27.3
Memory Proximity Domain Attributes Structure, the attached initiator is
defined as where the memory controller responsible for a memory proximity
domain. With attached initiator information, the topology of heterogeneous
memory can be described. Add new machine property 'hmat' to enable all
HMAT specific options.

Extend CLI of "-numa node" option to indicate the initiator numa node-id.
In the linux kernel, the codes in drivers/acpi/hmat/hmat.c parse and report
the platform's HMAT tables. Before using initiator option, enable HMAT with
-machine hmat=on.

Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Jingqi Liu <jingqi.liu@intel.com>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tao Xu <tao3.xu@intel.com>
Message-Id: <20191213011929.2520-2-tao3.xu@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 30 insertions, 5 deletions

diff --git a/qemu-options.hx b/qemu-options.hx
index e9d6231438..b78bc52634 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -40,7 +40,8 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
     "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
     "                nvdimm=on|off controls NVDIMM support (default=off)\n"
     "                enforce-config-section=on|off enforce configuration section migration (default=off)\n"
-    "                memory-encryption=@var{} memory encryption object to use (default=none)\n",
+    "                memory-encryption=@var{} memory encryption object to use (default=none)\n"
+    "                hmat=on|off controls ACPI HMAT support (default=off)\n",
     QEMU_ARCH_ALL)
 STEXI
 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
@@ -94,6 +95,9 @@ NOTE: this parameter is deprecated. Please use @option{-global}
 @option{migration.send-configuration}=@var{on|off} instead.
 @item memory-encryption=@var{}
 Memory encryption object to use. The default is none.
+@item hmat=on|off
+Enables or disables ACPI Heterogeneous Memory Attribute Table (HMAT) support.
+The default is off.
 @end table
 ETEXI
 
@@ -168,14 +172,14 @@ If any on the three values is given, the total number of CPUs @var{n} can be omi
 ETEXI
 
 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
-    "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
-    "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
+    "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node][,initiator=node]\n"
+    "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node][,initiator=node]\n"
     "-numa dist,src=source,dst=destination,val=distance\n"
     "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
     QEMU_ARCH_ALL)
 STEXI
-@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
-@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
+@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}][,initiator=@var{initiator}]
+@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}][,initiator=@var{initiator}]
 @itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance}
 @itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}]
 @findex -numa
@@ -222,6 +226,27 @@ split equally between them.
 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore,
 if one node uses @samp{memdev}, all of them have to use it.
 
+@samp{initiator} is an additional option that points to an @var{initiator}
+NUMA node that has best performance (the lowest latency or largest bandwidth)
+to this NUMA @var{node}. Note that this option can be set only when
+the machine property 'hmat' is set to 'on'.
+
+Following example creates a machine with 2 NUMA nodes, node 0 has CPU.
+node 1 has only memory, and its initiator is node 0. Note that because
+node 0 has CPU, by default the initiator of node 0 is itself and must be
+itself.
+@example
+-machine hmat=on \
+-m 2G,slots=2,maxmem=4G \
+-object memory-backend-ram,size=1G,id=m0 \
+-object memory-backend-ram,size=1G,id=m1 \
+-numa node,nodeid=0,memdev=m0 \
+-numa node,nodeid=1,memdev=m1,initiator=0 \
+-smp 2,sockets=2,maxcpus=2  \
+-numa cpu,node-id=0,socket-id=0 \
+-numa cpu,node-id=0,socket-id=1
+@end example
+
 @var{source} and @var{destination} are NUMA node IDs.
 @var{distance} is the NUMA distance from @var{source} to @var{destination}.
 The distance from a node to itself is always 10. If any pair of nodes is