Add support for Linux memory policy

Enable setting a NUMA memory policy for the container. New
linux.mempolicy object contains inputs to the set_mempolicy(2)
syscall.

Signed-off-by: Antti Kervinen <[email protected]>

Author: askervin

config-linux.md

@@ -690,6 +690,44 @@ and may use a maximum memory bandwidth of 20% on socket 0 and 70% on socket 1.
 }
 ```
 
+## <a name="configLinuxMempolicy" />Mempolicy
+
+**`mempolicy`** (object, OPTIONAL) sets the NUMA memory policy for the container.
+For more information see the [set_mempolicy(2)][set_mempolicy.2] man page.
+
+* **`mode`** *(string, REQUIRED)* -
+
+    A valid list of constants is shown below.
+
+    * `MPOL_DEFAULT`
+    * `MPOL_BIND`
+    * `MPOL_INTERLEAVE`
+    * `MPOL_WEIGHTED_INTERLEAVE`
+    * `MPOL_PREFERRED`
+    * `MPOL_LOCAL`
+
+* **`nodes`** *(string, REQUIRED)* - list of memory nodes from which nodemask is constructed to set_mempolicy(2). This is a comma-separated list, with dashes to represent ranges. For example, `0-3,7` represents memory nodes 0,1,2,3, and 7.
+
+* **`flags`** *(array of strings, OPTIONAL)* - list of flags to use with set_mempolicy(2).
+
+    A valid list of constants is shown below.
+
+    * `MPOL_F_NUMA_BALANCING`
+    * `MPOL_F_RELATIVE_NODES`
+    * `MPOL_F_STATIC_NODES`
+
+### Example
+
+```json
+"linux": {
+    "mempolicy": {
+        "mode": "MPOL_INTERLEAVE",
+        "nodes": "2-3"
+        "flags": ["MPOL_F_STATIC_NODES"],
+    }
+}
+```
+
 ## <a name="configLinuxSysctl" />Sysctl
 
 **`sysctl`** (object, OPTIONAL) allows kernel parameters to be modified at runtime for the container.
@@ -972,6 +1010,7 @@ subset of the available options.
 [tmpfs]: https://www.kernel.org/doc/Documentation/filesystems/tmpfs.txt
 
 [full.4]: https://man7.org/linux/man-pages/man4/full.4.html
+[set_mempolicy.2]: https://man7.org/linux/man-pages/man2/set_mempolicy.2.html
 [mknod.1]: https://man7.org/linux/man-pages/man1/mknod.1.html
 [mknod.2]: https://man7.org/linux/man-pages/man2/mknod.2.html
 [namespaces.7_2]: https://man7.org/linux/man-pages/man7/namespaces.7.html

schema/config-linux.json

@@ -277,6 +277,20 @@
                     }
                 }
             },
+            "mempolicy": {
+                "type": "object",
+                "properties": {
+                    "mode": {
+                        "$ref": "defs-linux.json#/definitions/MempolicyMode"
+                    },
+                    "nodes": {
+                        "type": "string"
+                    },
+                    "flags": {
+                        "$ref": "defs-linux.json#/definitions/MempolicyFlags"
+                    }
+                }
+            },
             "personality": {
                 "type": "object",
                 "$ref": "defs-linux.json#/definitions/Personality"

schema/defs-linux.json

@@ -264,6 +264,25 @@
                 "allow"
             ]
         },
+        "MempolicyMode": {
+            "type": "string",
+            "enum": [
+                "MPOL_DEFAULT",
+                "MPOL_BIND",
+                "MPOL_INTERLEAVE",
+                "MPOL_WEIGHTED_INTERLEAVE",
+                "MPOL_PREFERRED",
+                "MPOL_LOCAL"
+            ]
+        },
+        "MempolicyFlags": {
+            "type": "string",
+            "enum": [
+                "MPOL_F_NUMA_BALANCING",
+                "MPOL_F_RELATIVE_NODES",
+                "MPOL_F_STATIC_NODES"
+            ]
+        },
         "NetworkInterfacePriority": {
             "type": "object",
             "properties": {

specs-go/config.go

@@ -249,6 +249,8 @@ type Linux struct {
 	// IntelRdt contains Intel Resource Director Technology (RDT) information for
 	// handling resource constraints and monitoring metrics (e.g., L3 cache, memory bandwidth) for the container
 	IntelRdt *LinuxIntelRdt `json:"intelRdt,omitempty"`
+	// Mempolicy contains NUMA memory policy for the container.
+	Mempolicy *LinuxMempolicy `json:"mempolicy,omitempty"`
 	// Personality contains configuration for the Linux personality syscall
 	Personality *LinuxPersonality `json:"personality,omitempty"`
 	// TimeOffsets specifies the offset for supporting time namespaces.
@@ -847,6 +849,19 @@ type LinuxIntelRdt struct {
 	EnableMBM bool `json:"enableMBM,omitempty"`
 }
 
+// LinuxMempolicy represents input for the set_mempolicy syscall.
+type LinuxMempolicy struct {
+	// Mode for the set_mempolicy syscall.
+	Mode  MempolicyModeType   `json:"mode"`
+
+	// Nodes representing the nodemask for the set_mempolicy syscall in comma separated ranges format.
+	// Format: "<node0>-<node1>,<node2>,<node3>-<node4>,..."
+	Nodes string              `json:"nodes"`
+
+	// Flags for the set_mempolicy syscall.
+	Flags []MempolicyFlagType `json:"flags,omitempty"`
+}
+
 // ZOS contains platform-specific configuration for z/OS based containers.
 type ZOS struct {
 	// Namespaces contains the namespaces that are created and/or joined by the container
@@ -876,6 +891,25 @@ const (
 	ZOSUTSNamespace ZOSNamespaceType = "uts"
 )
 
+type MempolicyModeType string
+
+const (
+	MpolDefault            MempolicyModeType = "MPOL_DEFAULT"
+	MpolBind               MempolicyModeType = "MPOL_BIND"
+	MpolInterleave         MempolicyModeType = "MPOL_INTERLEAVE"
+	MpolWeightedInterleave MempolicyModeType = "MPOL_WEIGHTED_INTERLEAVE"
+	MpolPreferred          MempolicyModeType = "MPOL_PREFERRED"
+	MpolLocal              MempolicyModeType = "MPOL_LOCAL"
+)
+
+type MempolicyFlagType string
+
+const (
+	MpolFNumaBalancing MempolicyFlagType = "MPOL_F_NUMA_BALANCING"
+	MpolFRelativeNodes MempolicyFlagType = "MPOL_F_RELATIVE_NODES"
+	MpolFStaticNodes   MempolicyFlagType = "MPOL_F_STATIC_NODES"
+)
+
 // LinuxSchedulerPolicy represents different scheduling policies used with the Linux Scheduler
 type LinuxSchedulerPolicy string