Add support for memory.stat kernel field

Summary:
Display `kernel` field from `memory.stat` - kernel memory used by cgroup.
This was added in 5.18: torvalds/linux@a8c49af3be5f0
This field is not present in `memory.numa.stat`

Reviewed By: brianc118

Differential Revision: D51832461

fbshipit-source-id: 98ca0561e05bb626edd3e0f285756191e0cc783c

below/cgroupfs/src/lib.rs

@@ -657,6 +657,7 @@ key_values_format!(CpuStat; cpu.stat; [
 key_values_format!(MemoryStat; memory.stat; [
     anon,
     file,
+    kernel,
     kernel_stack,
     slab,
     sock,

below/cgroupfs/src/types.rs

@@ -52,6 +52,7 @@ pub struct IoStat {
 pub struct MemoryStat {
     pub anon: Option<u64>,
     pub file: Option<u64>,
+    pub kernel: Option<u64>,
     pub kernel_stack: Option<u64>,
     pub slab: Option<u64>,
     pub sock: Option<u64>,

below/dump/src/test.rs

@@ -497,6 +497,7 @@ fn test_dump_cgroup_titles() {
         "Mem Swap",
         "Mem Anon",
         "Mem File",
+        "Kernel",
         "Kernel Stack",
         "Mem Slab",
         "Mem Sock",

below/model/src/cgroup.rs

@@ -471,6 +471,7 @@ pub struct CgroupMemoryModel {
     pub swap: Option<u64>,
     pub anon: Option<u64>,
     pub file: Option<u64>,
+    pub kernel: Option<u64>,
     pub kernel_stack: Option<u64>,
     pub slab: Option<u64>,
     pub sock: Option<u64>,
@@ -522,6 +523,7 @@ impl std::ops::Add for CgroupMemoryModel {
             swap: opt_add(self.swap, other.swap),
             anon: opt_add(self.anon, other.anon),
             file: opt_add(self.file, other.file),
+            kernel: opt_add(self.kernel, other.kernel),
             kernel_stack: opt_add(self.kernel_stack, other.kernel_stack),
             slab: opt_add(self.slab, other.slab),
             sock: opt_add(self.sock, other.sock),
@@ -608,6 +610,7 @@ impl CgroupMemoryModel {
         if let Some(stat) = &sample.memory_stat {
             model.anon = stat.anon;
             model.file = stat.file;
+            model.kernel = stat.kernel;
             model.kernel_stack = stat.kernel_stack;
             model.slab = stat.slab;
             model.sock = stat.sock;

below/model/src/common_field_ids.rs

@@ -23,7 +23,7 @@
 ///
 /// This list also servers as documentation for available field ids that could
 /// be used in other below crates. A test ensures that this list is up-to-date.
-pub const COMMON_MODEL_FIELD_IDS: [&str; 373] = [
+pub const COMMON_MODEL_FIELD_IDS: [&str; 374] = [
     "system.hostname",
     "system.kernel_version",
     "system.os_release",
@@ -156,6 +156,7 @@ pub const COMMON_MODEL_FIELD_IDS: [&str; 373] = [
     "cgroup.[path:/<cgroup_path>/.]mem.swap",
     "cgroup.[path:/<cgroup_path>/.]mem.anon",
     "cgroup.[path:/<cgroup_path>/.]mem.file",
+    "cgroup.[path:/<cgroup_path>/.]mem.kernel",
     "cgroup.[path:/<cgroup_path>/.]mem.kernel_stack",
     "cgroup.[path:/<cgroup_path>/.]mem.slab",
     "cgroup.[path:/<cgroup_path>/.]mem.sock",

below/render/src/default_configs.rs

@@ -200,6 +200,7 @@ impl HasRenderConfigForDump for model::SingleCgroupModel {
                 EventsOomKill => Some(counter),
                 Anon => Some(gauge.unit("bytes")),
                 File => Some(gauge.unit("bytes")),
+                Kernel => Some(gauge.unit("bytes")),
                 KernelStack => Some(gauge.unit("bytes")),
                 Slab => Some(gauge.unit("bytes")),
                 Sock => Some(gauge.unit("bytes")),
@@ -309,6 +310,7 @@ impl HasRenderConfig for model::CgroupMemoryModel {
             EventsOomKill => rc.title("Events Kill"),
             Anon => rc.title("Anon").format(ReadableSize),
             File => rc.title("File").format(ReadableSize),
+            Kernel => rc.title("Kernel").format(ReadableSize),
             KernelStack => rc.title("Kernel Stack").format(ReadableSize),
             Slab => rc.title("Slab").format(ReadableSize),
             Sock => rc.title("Sock").format(ReadableSize),

below/view/src/cgroup_tabs.rs

@@ -253,6 +253,7 @@ pub mod default_tabs {
     use model::CgroupMemoryModelFieldId::FileWriteback;
     use model::CgroupMemoryModelFieldId::InactiveAnon;
     use model::CgroupMemoryModelFieldId::InactiveFile;
+    use model::CgroupMemoryModelFieldId::Kernel;
     use model::CgroupMemoryModelFieldId::KernelStack;
     use model::CgroupMemoryModelFieldId::Pgactivate;
     use model::CgroupMemoryModelFieldId::Pgdeactivate;
@@ -352,6 +353,7 @@ pub mod default_tabs {
             ViewItem::from_default(Mem(Swap)),
             ViewItem::from_default(Mem(Anon)),
             ViewItem::from_default(Mem(File)),
+            ViewItem::from_default(Mem(Kernel)),
             ViewItem::from_default(Mem(KernelStack)),
             ViewItem::from_default(Mem(Slab)),
             ViewItem::from_default(Mem(Sock)),