Add support for systemd managed cgroups

.github/workflows/main.yml

@@ -12,6 +12,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - run: rustup component add clippy
+      - run: sudo apt-get install -y pkg-config libsystemd-dev libdbus-glib-1-dev
       - uses: actions-rs/clippy-check@v1
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
@@ -30,6 +31,7 @@ jobs:
       - uses: actions-rs/toolchain@v1
         with:
           toolchain: stable
+      - run: sudo apt-get install -y pkg-config libsystemd-dev libdbus-glib-1-dev
       - run: cargo install cargo-when
       - name: Build
         run: ./build.sh

Cargo.toml

@@ -22,6 +22,8 @@ once_cell = "1.6.0"
 futures = { version = "0.3", features = ["thread-pool"] }
 regex = "1.5"
 oci_spec = { version = "0.1.0", path = "./oci_spec" }
+systemd = { version = "0.8", default-features = false }
+dbus = "0.9.2"
 
 [dev-dependencies]
 oci_spec = { version = "0.1.0", path = "./oci_spec", features = ["proptests"] }

README.md

@@ -40,12 +40,29 @@ For other platforms, please use the devcontainer that we prepared.
 - Rust(See [here](https://www.rust-lang.org/tools/install))
 - Docker(See [here](https://docs.docker.com/engine/install))
 
-## Building
+## Dependencies
+```sh
+$ cargo install cargo-when
+```
+
+### Debian, Ubuntu and related distributions
+```sh
+$ sudo dnf install        \
+      pkg-config          \
+      libsystemd-dev      \
+      libdbus-glib-1-dev
+```
+
 
+### Fedora, Centos, RHEL and related distributions
 ```sh
-$ cargo install cargo-when # installs prerequisite for building youki
+$ sudo dnf install \
+      pkg-config   \
+      systemd-dev  \
+      dbus-devel
 ```
 
+## Build
 ```sh
 $ git clone git@github.com:containers/youki.git
 $ cd youki

src/cgroups/common.rs

@@ -6,11 +6,11 @@ use std::{
     path::{Path, PathBuf},
 };
 
-
 use anyhow::{bail, Context, Result};
 use nix::unistd::Pid;
 use oci_spec::LinuxResources;
 use procfs::process::Process;
+use systemd::daemon::booted;
 
 use crate::cgroups::v1;
 use crate::cgroups::v2;
@@ -91,7 +91,10 @@ pub fn get_supported_cgroup_fs() -> Result<Vec<Cgroup>> {
     Ok(cgroups)
 }
 
-pub fn create_cgroup_manager<P: Into<PathBuf>>(cgroup_path: P) -> Result<Box<dyn CgroupManager>> {
+pub fn create_cgroup_manager<P: Into<PathBuf>>(
+    cgroup_path: P,
+    systemd_cgroup: bool,
+) -> Result<Box<dyn CgroupManager>> {
     let cgroup_mount = Process::myself()?
         .mountinfo()?
         .into_iter()
@@ -109,6 +112,16 @@ pub fn create_cgroup_manager<P: Into<PathBuf>>(cgroup_path: P) -> Result<Box<dyn
         }
         (None, Some(cgroup2)) => {
             log::info!("cgroup manager V2 will be used");
+            if systemd_cgroup {
+                if !booted()? {
+                    bail!("systemd cgroup flag passed, but systemd support for managing cgroups is not available");
+                }
+                log::info!("systemd cgroup manager will be used");
+                return Ok(Box::new(v2::SystemDCGroupManager::new(
+                    cgroup2.mount_point,
+                    cgroup_path.into(),
+                )?));
+            }
             Ok(Box::new(v2::manager::Manager::new(
                 cgroup2.mount_point,
                 cgroup_path.into(),
@@ -119,6 +132,16 @@ pub fn create_cgroup_manager<P: Into<PathBuf>>(cgroup_path: P) -> Result<Box<dyn
             match cgroup_override {
                 Ok(v) if v == "true" => {
                     log::info!("cgroup manager V2 will be used");
+                    if systemd_cgroup {
+                        if !booted()? {
+                            bail!("systemd cgroup flag passed, but systemd support for managing cgroups is not available");
+                        }
+                        log::info!("systemd cgroup manager will be used");
+                        return Ok(Box::new(v2::SystemDCGroupManager::new(
+                            cgroup2.mount_point,
+                            cgroup_path.into(),
+                        )?));
+                    }
                     Ok(Box::new(v2::manager::Manager::new(
                         cgroup2.mount_point,
                         cgroup_path.into(),

src/cgroups/v1/util.rs

@@ -45,4 +45,4 @@ pub fn get_subsystem_mount_points(subsystem: &str) -> Result<PathBuf> {
         })
         .map(|m| m.mount_point)
         .ok_or_else(|| anyhow!("could not find mountpoint for {}", subsystem))
-}
+}

src/cgroups/v2/mod.rs

@@ -7,4 +7,6 @@ mod io;
 pub mod manager;
 mod memory;
 mod pids;
+pub mod systemd_manager;
 pub mod util;
+pub use systemd_manager::SystemDCGroupManager;