Merge pull request #17 from Tim-Zhang/minor-updates

Minor updates

src/hierarchies.rs

@@ -8,7 +8,6 @@
 //!
 //! Currently, we only support the cgroupv1 hierarchy, but in the future we will add support for
 //! the Unified Hierarchy.
-use nix::sys::statfs;
 
 use std::fs::{self, File};
 use std::io::BufRead;
@@ -220,6 +219,8 @@ pub const UNIFIED_MOUNTPOINT: &'static str = "/sys/fs/cgroup";
 
 #[cfg(all(target_os = "linux", not(target_env = "musl")))]
 pub fn is_cgroup2_unified_mode() -> bool {
+    use nix::sys::statfs;
+
     let path = Path::new(UNIFIED_MOUNTPOINT);
     let fs_stat = statfs::statfs(path);
     if fs_stat.is_err() {

src/lib.rs

@@ -619,7 +619,7 @@ impl Subsystem {
         }
     }
 
-    fn to_controller(&self) -> &dyn Controller {
+    pub fn to_controller(&self) -> &dyn Controller {
         match self {
             Subsystem::Pid(cont) => cont,
             Subsystem::Mem(cont) => cont,
@@ -638,7 +638,7 @@ impl Subsystem {
         }
     }
 
-    fn controller_name(&self) -> String {
+    pub fn controller_name(&self) -> String {
         self.to_controller().control_type().to_string()
     }
 }

src/memory.rs

@@ -733,6 +733,15 @@ impl MemController {
             })
     }
 
+    /// Reset the max memory usage recorded
+    pub fn reset_max_usage(&self) -> Result<()> {
+        self.open_path("memory.max_usage_in_bytes", true)
+            .and_then(|mut file| {
+                file.write_all("0".to_string().as_ref())
+                    .map_err(|e| Error::with_cause(WriteFailed, e))
+            })
+    }
+
     /// Set the memory usage limit of the control group, in bytes.
     pub fn set_limit(&self, limit: i64) -> Result<()> {
         let mut file = "memory.limit_in_bytes";