vmm: Add 'host_numa_nodes' option to memory zones

Since memory zones have been introduced, it is now possible for a user
to specify multiple backends for the guest RAM. By adding a new option
'host_numa_node' to the 'memory-zone' parameter, we allow the guest RAM
to be backed by memory that might come from a specific NUMA node on the
host.

The option expects a node identifier, specifying which NUMA node should
be used to allocate the memory associated with a specific memory zone.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

src/main.rs

@@ -120,7 +120,7 @@ fn create_app<'a, 'b>(
                 .help(
                     "User defined memory zone parameters \
                      \"size=<guest_memory_region_size>,file=<backing_file>,\
-                     shared=on|off,hugepages=on|off\"",
+                     shared=on|off,hugepages=on|off,host_numa_node=<node_id>\"",
                 )
                 .takes_value(true)
                 .min_values(1)

vmm/src/api/openapi/cloud-hypervisor.yaml

@@ -467,6 +467,8 @@ components:
         hugepages:
           type: boolean
           default: false
+        host_numa_node:
+          type: uint64
 
     MemoryConfig:
       required:

vmm/src/config.rs

@@ -352,6 +352,8 @@ pub struct MemoryZoneConfig {
     pub shared: bool,
     #[serde(default)]
     pub hugepages: bool,
+    #[serde(default)]
+    pub host_numa_node: Option<u64>,
 }
 
 #[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
@@ -431,7 +433,8 @@ impl MemoryConfig {
                     .add("size")
                     .add("file")
                     .add("shared")
-                    .add("hugepages");
+                    .add("hugepages")
+                    .add("host_numa_node");
                 parser.parse(memory_zone).map_err(Error::ParseMemoryZone)?;
 
                 let size = parser
@@ -450,12 +453,16 @@ impl MemoryConfig {
                     .map_err(Error::ParseMemoryZone)?
                     .unwrap_or(Toggle(false))
                     .0;
+                let host_numa_node = parser
+                    .convert::<u64>("host_numa_node")
+                    .map_err(Error::ParseMemoryZone)?;
 
                 zones.push(MemoryZoneConfig {
                     size,
                     file,
                     shared,
                     hugepages,
+                    host_numa_node,
                 });
             }
             Some(zones)

vmm/src/memory_manager.rs

@@ -364,6 +364,7 @@ impl MemoryManager {
                 file: None,
                 shared: config.shared,
                 hugepages: config.hugepages,
+                host_numa_node: None,
             }];
 
             (config.size, zones)