subkernel: support no-timeout, message passing

src/libksupport/src/kernel/mod.rs

@@ -87,7 +87,7 @@ pub enum Message {
     #[cfg(has_drtio)]
     SubkernelAwaitFinishRequest {
         id: u32,
-        timeout: u64,
+        timeout: i64,
     },
     #[cfg(has_drtio)]
     SubkernelAwaitFinishReply {
@@ -104,7 +104,7 @@ pub enum Message {
     #[cfg(has_drtio)]
     SubkernelMsgRecvRequest {
         id: u32,
-        timeout: u64,
+        timeout: i64,
         tags: Vec<u8>,
     },
     #[cfg(has_drtio)]

src/runtime/src/subkernel.rs

@@ -169,25 +169,34 @@ pub async fn await_finish(
     routing_table: &RoutingTable,
     timer: GlobalTimer,
     id: u32,
-    timeout: u64,
+    timeout: i64,
 ) -> Result<SubkernelFinished, Error> {
     match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
         SubkernelState::Running | SubkernelState::Finished { .. } => (),
         _ => return Err(Error::IncorrectState),
     }
-    let max_time = timer.get_time() + Milliseconds(timeout);
-    while timer.get_time() < max_time {
-        {
+    if timeout > 0 {
+        let max_time = timer.get_time() + Milliseconds(timeout);
+        while timer.get_time() < max_time {
             match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
                 SubkernelState::Finished { .. } => break,
                 _ => (),
             };
+            task::r#yield().await;
+        }
+        if timer.get_time() >= max_time {
+            error!("Remote subkernel finish await timed out");
+            return Err(Error::Timeout);
+        }
+    } else {
+        // no timeout, wait forever
+        loop {
+            match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
+                SubkernelState::Finished { .. } => break,
+                _ => (),
+            };
+            task::r#yield().await;
         }
-        task::r#yield().await;
-    }
-    if timer.get_time() >= max_time {
-        error!("Remote subkernel finish await timed out");
-        return Err(Error::Timeout);
     }
     if let Some(subkernel) = SUBKERNELS.async_lock().await.get_mut(&id) {
         match subkernel.state {
@@ -231,8 +240,9 @@ pub async fn message_handle_incoming(
     {
         let subkernel_lock = SUBKERNELS.async_lock().await;
         let subkernel = subkernel_lock.get(&id);
-        if subkernel.is_none() || subkernel.unwrap().state != SubkernelState::Running {
-            // do not add messages for non-existing or deleted subkernels
+        if subkernel.is_some() && subkernel.unwrap().state != SubkernelState::Running {
+            // do not add messages for non-running or deleted subkernels
+            warn!("received a message for a non-running subkernel #{}", id);
             return;
         }
     }
@@ -264,16 +274,19 @@ pub async fn message_handle_incoming(
     }
 }
 
-pub async fn message_await(id: u32, timeout: u64, timer: GlobalTimer) -> Result<Message, Error> {
-    match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
-        SubkernelState::Finished {
-            status: FinishStatus::CommLost,
-        } => return Err(Error::CommLost),
-        SubkernelState::Running | SubkernelState::Finished { .. } => (),
-        _ => return Err(Error::IncorrectState),
+pub async fn message_await(id: u32, timeout: i64, timer: GlobalTimer) -> Result<Message, Error> {
+    let is_subkernel = SUBKERNELS.async_lock().await.get(&id).is_some();
+    if is_subkernel {
+        match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
+            SubkernelState::Finished {
+                status: FinishStatus::CommLost,
+            } => return Err(Error::CommLost),
+            SubkernelState::Running | SubkernelState::Finished { .. } => (),
+            _ => return Err(Error::IncorrectState),
+        }
     }
     let max_time = timer.get_time() + Milliseconds(timeout);
-    while timer.get_time() < max_time {
+    while timeout < 0 || (timeout > 0 && timer.get_time() < max_time) {
         {
             let mut message_queue = MESSAGE_QUEUE.async_lock().await;
             for i in 0..message_queue.len() {
@@ -284,14 +297,16 @@ pub async fn message_await(id: u32, timeout: u64, timer: GlobalTimer) -> Result<
                 }
             }
         }
-        match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
-            SubkernelState::Finished {
-                status: FinishStatus::CommLost,
-            } => return Err(Error::CommLost),
-            SubkernelState::Finished {
-                status: FinishStatus::Exception(_),
-            } => return Err(Error::SubkernelException),
-            _ => (),
+        if is_subkernel {
+            match SUBKERNELS.async_lock().await.get(&id).unwrap().state {
+                SubkernelState::Finished {
+                    status: FinishStatus::CommLost,
+                } => return Err(Error::CommLost),
+                SubkernelState::Finished {
+                    status: FinishStatus::Exception(_),
+                } => return Err(Error::SubkernelException),
+                _ => (),
+            }
         }
         task::r#yield().await;
     }

src/satman/src/subkernel.rs

@@ -1,4 +1,4 @@
-use alloc::{collections::{BTreeMap, VecDeque},
+use alloc::{collections::BTreeMap,
             format,
             string::{String, ToString},
             vec::Vec};
@@ -23,11 +23,15 @@ enum KernelState {
     Absent,
     Loaded,
     Running,
-    MsgAwait(Milliseconds, Vec<u8>),
+    MsgAwait {
+        max_time: Option<Milliseconds>,
+        id: u32,
+        tags: Vec<u8>
+    },
     MsgSending,
     SubkernelAwaitLoad,
     SubkernelAwaitFinish {
-        max_time: Milliseconds,
+        max_time: Option<Milliseconds>,
         id: u32,
     },
     DmaUploading,
@@ -110,7 +114,7 @@ enum OutMessageState {
 struct MessageManager {
     out_message: Option<Sliceable>,
     out_state: OutMessageState,
-    in_queue: VecDeque<Message>,
+    in_queue: Vec<Message>,
     in_buffer: Option<Message>,
 }
 
@@ -170,7 +174,7 @@ impl MessageManager {
         MessageManager {
             out_message: None,
             out_state: OutMessageState::NoMessage,
-            in_queue: VecDeque::new(),
+            in_queue: Vec::new(),
             in_buffer: None,
         }
     }
@@ -191,7 +195,7 @@ impl MessageManager {
         };
         if status.is_last() {
             // when done, remove from working queue
-            self.in_queue.push_back(self.in_buffer.take().unwrap());
+            self.in_queue.push(self.in_buffer.take().unwrap());
         }
     }
 
@@ -265,8 +269,13 @@ impl MessageManager {
         Ok(())
     }
 
-    pub fn get_incoming(&mut self) -> Option<Message> {
-        self.in_queue.pop_front()
+    pub fn get_incoming(&mut self, id: u32) -> Option<Message> {
+        for i in 0..self.in_queue.len() {
+            if self.in_queue[i].id == id {
+                return Some(self.in_queue.remove(i));
+            }
+        }
+        None
     }
 }
 
@@ -707,9 +716,13 @@ impl<'a> Manager<'_> {
                 )?;
                 self.session.kernel_state = KernelState::MsgSending;
             }
-            kernel::Message::SubkernelMsgRecvRequest { id: _, timeout, tags } => {
-                let max_time = timer.get_time() + Milliseconds(timeout);
-                self.session.kernel_state = KernelState::MsgAwait(max_time, tags);
+            kernel::Message::SubkernelMsgRecvRequest { id, timeout, tags } => {
+                let max_time = if timeout > 0 {
+                    Some(timer.get_time() + Milliseconds(timeout));
+                } else {
+                    None
+                }
+                self.session.kernel_state = KernelState::MsgAwait { max_time: max_time, id:id, tags: tags };
             }
             kernel::Message::SubkernelLoadRunRequest {
                 id,
@@ -731,7 +744,11 @@ impl<'a> Manager<'_> {
             }
 
             kernel::Message::SubkernelAwaitFinishRequest { id, timeout } => {
-                let max_time = timer.get_time() + Milliseconds(timeout);
+                let max_time = if timeout > 0 {
+                    Some(timer.get_time() + Milliseconds(timeout));
+                } else {
+                    None
+                }
                 self.session.kernel_state = KernelState::SubkernelAwaitFinish {
                     max_time: max_time,
                     id: id,
@@ -751,16 +768,18 @@ impl<'a> Manager<'_> {
 
     fn process_external_messages(&mut self, timer: &GlobalTimer) -> Result<(), Error> {
         match &self.session.kernel_state {
-            KernelState::MsgAwait(timeout, tags) => {
-                if timer.get_time() > *timeout {
-                    self.control.tx.send(kernel::Message::SubkernelMsgRecvReply {
-                        status: kernel::SubkernelStatus::Timeout,
-                        count: 0,
-                    });
-                    self.session.kernel_state = KernelState::Running;
-                    return Ok(());
+            KernelState::MsgAwait {max_time , id, tags } => {
+                if let Some(max_time) = *max_time {
+                    if timer.get_time() > max_time {
+                        self.control.tx.send(kernel::Message::SubkernelMsgRecvReply {
+                            status: kernel::SubkernelStatus::Timeout,
+                            count: 0,
+                        });
+                        self.session.kernel_state = KernelState::Running;
+                        return Ok(());
+                    }
                 }
-                if let Some(message) = self.session.messages.get_incoming() {
+                if let Some(message) = self.session.messages.get_incoming(id) {
                     self.control.tx.send(kernel::Message::SubkernelMsgRecvReply {
                         status: kernel::SubkernelStatus::NoError,
                         count: message.count,
@@ -782,25 +801,27 @@ impl<'a> Manager<'_> {
                 }
             }
             KernelState::SubkernelAwaitFinish { max_time, id } => {
-                if timer.get_time() > *max_time {
-                    self.control.tx.send(kernel::Message::SubkernelAwaitFinishReply {
-                        status: kernel::SubkernelStatus::Timeout,
-                    });
-                    self.session.kernel_state = KernelState::Running;
-                } else {
-                    let mut i = 0;
-                    for status in &self.session.subkernels_finished {
-                        if *status == *id {
-                            self.control.tx.send(kernel::Message::SubkernelAwaitFinishReply {
-                                status: kernel::SubkernelStatus::NoError,
-                            });
-                            self.session.kernel_state = KernelState::Running;
-                            self.session.subkernels_finished.swap_remove(i);
-                            break;
-                        }
-                        i += 1;
+                if let Some(max_time) = *max_time {
+                    if timer.get_time() > *max_time {
+                        self.control.tx.send(kernel::Message::SubkernelAwaitFinishReply {
+                            status: kernel::SubkernelStatus::Timeout,
+                        });
+                        self.session.kernel_state = KernelState::Running;
+                        return Ok(());
                     }
                 }
+                let mut i = 0;
+                for status in &self.session.subkernels_finished {
+                    if *status == *id {
+                        self.control.tx.send(kernel::Message::SubkernelAwaitFinishReply {
+                            status: kernel::SubkernelStatus::NoError,
+                        }); 
+                        self.session.kernel_state = KernelState::Running;
+                        self.session.subkernels_finished.swap_remove(i);
+                        break;
+                    }
+                    i += 1;
+                }
                 Ok(())
             }
             KernelState::DmaAwait { max_time } | KernelState::DmaPendingAwait { max_time, .. } => {