Drop context when process exit. Remove util mod.

crate/process/src/lib.rs

@@ -2,6 +2,7 @@
 #![feature(alloc)]
 #![feature(const_fn)]
 #![feature(linkage)]
+#![feature(nll)]
 
 extern crate alloc;
 #[macro_use]
@@ -17,7 +18,6 @@ mod process_manager;
 mod processor;
 pub mod scheduler;
 pub mod thread;
-mod util;
 mod event_hub;
 
 pub use process_manager::*;

crate/process/src/process_manager.rs

@@ -19,8 +19,8 @@ const MAX_PROC_NUM: usize = 32;
 pub enum Status {
     Ready,
     Running(usize),
-    Waiting(Pid),
     Sleeping,
+    /// aka ZOMBIE. Its context was dropped.
     Exited(ExitCode),
 }
 
@@ -98,8 +98,10 @@ impl ProcessManager {
         proc.status = proc.status_after_stop.clone();
         proc.status_after_stop = Status::Ready;
         proc.context = Some(context);
-        if proc.status == Status::Ready {
-            self.scheduler.lock().insert(pid);
+        match proc.status {
+            Status::Ready => self.scheduler.lock().insert(pid),
+            Status::Exited(_) => proc.context = None,
+            _ => {}
         }
     }
 
@@ -121,5 +123,9 @@ impl ProcessManager {
             Status::Running(_) => proc.status_after_stop = status,
             _ => proc.status = status,
         }
+        match proc.status {
+            Status::Exited(_) => proc.context = None,
+            _ => {}
+        }
     }
 }

crate/process/src/util.rs

@@ -1,15 +0,0 @@
-use core::fmt::Debug;
-
-/// Get values by 2 diff keys at the same time
-pub trait GetMut2<Idx: Debug + Eq> {
-    type Output;
-    fn get_mut(&mut self, id: Idx) -> &mut Self::Output;
-    fn get_mut2(&mut self, id1: Idx, id2: Idx) -> (&mut Self::Output, &mut Self::Output) {
-        assert_ne!(id1, id2);
-        let self1 = self as *mut Self;
-        let self2 = self1;
-        let p1 = unsafe { &mut *self1 }.get_mut(id1);
-        let p2 = unsafe { &mut *self2 }.get_mut(id2);
-        (p1, p2)
-    }
-}