Handle io flush during write back-pressure (#246)

ntex-io/CHANGES.md

@@ -1,5 +1,9 @@
 # Changes
 
+## [0.3.7] - 2023-11-12
+
+* Handle io flush during write back-pressure
+
 ## [0.3.6] - 2023-11-11
 
 * Add support for frame read timeout

ntex-io/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ntex-io"
-version = "0.3.6"
+version = "0.3.7"
 authors = ["ntex contributors <team@ntex.rs>"]
 description = "Utilities for encoding and decoding frames"
 keywords = ["network", "framework", "async", "futures"]
@@ -17,7 +17,7 @@ path = "src/lib.rs"
 
 [dependencies]
 ntex-codec = "0.6.2"
-ntex-bytes = "0.1.20"
+ntex-bytes = "0.1.21"
 ntex-util = "0.3.4"
 ntex-service = "1.2.7"
 
@@ -29,4 +29,4 @@ pin-project-lite = "0.2"
 rand = "0.8"
 env_logger = "0.10"
 
-ntex = { version = "0.7.0", features = ["tokio"] }
+ntex = { version = "0.7", features = ["tokio"] }

ntex-io/src/dispatcher.rs

@@ -31,7 +31,7 @@ impl Default for DispatcherConfig {
     fn default() -> Self {
         DispatcherConfig(Rc::new(DispatcherConfigInner {
             keepalive_timeout: Cell::new(Seconds(30).into()),
-            disconnect_timeout: Cell::new(Seconds(1).into()),
+            disconnect_timeout: Cell::new(Seconds(1)),
             frame_read_rate: Cell::new(0),
             frame_read_enabled: Cell::new(false),
             frame_read_timeout: Cell::new(Seconds::ZERO.into()),
@@ -92,8 +92,9 @@ impl DispatcherConfig {
 
     /// Set read rate parameters for single frame.
     ///
-    /// Set max timeout for reading single frame. If the client sends data,
-    /// increase the timeout by 1 second for every.
+    /// Set max timeout for reading single frame. If the client
+    /// sends `rate` amount of data, increase the timeout by 1 second for every.
+    /// But no more than `max_timeout` timeout.
     ///
     /// By default frame read rate is disabled.
     pub fn set_frame_read_rate(
@@ -320,8 +321,7 @@ where
         loop {
             match slf.st {
                 DispatcherState::Processing => {
-                    let srv = ready!(slf.poll_service(cx));
-                    let item = match srv {
+                    let item = match ready!(slf.poll_service(cx)) {
                         PollService::Ready => {
                             // decode incoming bytes if buffer is ready
                             match slf.shared.io.poll_recv_decode(&slf.shared.codec, cx) {
@@ -386,11 +386,12 @@ where
                 DispatcherState::Backpressure => {
                     let item = match ready!(slf.poll_service(cx)) {
                         PollService::Ready => {
-                            if slf.shared.io.poll_flush(cx, false).is_ready() {
+                            if let Err(err) = ready!(slf.shared.io.poll_flush(cx, false)) {
+                                slf.st = DispatcherState::Stop;
+                                DispatchItem::Disconnect(Some(err))
+                            } else {
                                 slf.st = DispatcherState::Processing;
                                 DispatchItem::WBackPressureDisabled
-                            } else {
-                                return Poll::Pending;
                             }
                         }
                         PollService::Item(item) => item,

ntex-io/src/filter.rs

@@ -78,15 +78,15 @@ impl Filter for Base {
 
         if flags.intersects(Flags::IO_STOPPING | Flags::IO_STOPPED) {
             Poll::Ready(ReadStatus::Terminate)
-        } else if flags.intersects(Flags::IO_STOPPING_FILTERS) {
-            self.0 .0.read_task.register(cx.waker());
-            Poll::Ready(ReadStatus::Ready)
-        } else if flags.intersects(Flags::RD_PAUSED | Flags::RD_BUF_FULL) {
-            self.0 .0.read_task.register(cx.waker());
-            Poll::Pending
         } else {
             self.0 .0.read_task.register(cx.waker());
-            Poll::Ready(ReadStatus::Ready)
+            if flags.intersects(Flags::IO_STOPPING_FILTERS) {
+                Poll::Ready(ReadStatus::Ready)
+            } else if flags.intersects(Flags::RD_PAUSED | Flags::RD_BUF_FULL) {
+                Poll::Pending
+            } else {
+                Poll::Ready(ReadStatus::Ready)
+            }
         }
     }
 

ntex-io/src/tasks.rs

@@ -38,33 +38,44 @@ impl ReadContext {
 
         // handle buffer changes
         if nbytes > 0 {
-            let buf_full = nbytes >= hw;
             let filter = self.0.filter();
             let _ = filter
                 .process_read_buf(&self.0, &inner.buffer, 0, nbytes)
                 .and_then(|status| {
                     if status.nbytes > 0 {
-                        if buf_full || inner.buffer.read_destination_size() >= hw {
+                        // dest buffer has new data, wake up dispatcher
+                        if inner.buffer.read_destination_size() >= hw {
                             log::trace!(
                                 "io read buffer is too large {}, enable read back-pressure",
                                 total
                             );
                             inner.insert_flags(Flags::RD_READY | Flags::RD_BUF_FULL);
                         } else {
                             inner.insert_flags(Flags::RD_READY);
+
+                            if nbytes >= hw {
+                                // read task is paused because of read back-pressure
+                                // but there is no new data in top most read buffer
+                                // so we need to wake up read task to read more data
+                                // otherwise read task would sleep forever
+                                inner.read_task.wake();
+                            }
                         }
                         log::trace!("new {} bytes available, wakeup dispatcher", nbytes);
                         inner.dispatch_task.wake();
-                    } else if buf_full {
-                        // read task is paused because of read back-pressure
-                        // but there is no new data in top most read buffer
-                        // so we need to wake up read task to read more data
-                        // otherwise read task would sleep forever
-                        inner.read_task.wake();
-                    } else if inner.flags.get().contains(Flags::RD_FORCE_READY) {
-                        // in case of "force read" we must wake up dispatch task
-                        // if we read any data from source
-                        inner.dispatch_task.wake();
+                    } else {
+                        if nbytes >= hw {
+                            // read task is paused because of read back-pressure
+                            // but there is no new data in top most read buffer
+                            // so we need to wake up read task to read more data
+                            // otherwise read task would sleep forever
+                            inner.read_task.wake();
+                        }
+                        if inner.flags.get().contains(Flags::RD_FORCE_READY) {
+                            // in case of "force read" we must wake up dispatch task
+                            // if we read any data from source
+                            inner.dispatch_task.wake();
+                        }
                     }
 
                     // while reading, filter wrote some data
@@ -78,8 +89,8 @@ impl ReadContext {
                 })
                 .map_err(|err| {
                     inner.dispatch_task.wake();
-                    inner.insert_flags(Flags::RD_READY);
                     inner.io_stopped(Some(err));
+                    inner.insert_flags(Flags::RD_READY);
                 });
         }
 

ntex-tokio/src/io.rs

@@ -132,8 +132,8 @@ impl Future for WriteTask {
 
         match this.st {
             IoWriteState::Processing(ref mut delay) => {
-                match this.state.poll_ready(cx) {
-                    Poll::Ready(WriteStatus::Ready) => {
+                match ready!(this.state.poll_ready(cx)) {
+                    WriteStatus::Ready => {
                         if let Some(delay) = delay {
                             if delay.poll_elapsed(cx).is_ready() {
                                 this.state.close(Some(io::Error::new(
@@ -157,14 +157,14 @@ impl Future for WriteTask {
                             }
                         }
                     }
-                    Poll::Ready(WriteStatus::Timeout(time)) => {
+                    WriteStatus::Timeout(time) => {
                         log::trace!("initiate timeout delay for {:?}", time);
                         if delay.is_none() {
                             *delay = Some(sleep(time));
                         }
                         self.poll(cx)
                     }
-                    Poll::Ready(WriteStatus::Shutdown(time)) => {
+                    WriteStatus::Shutdown(time) => {
                         log::trace!("write task is instructed to shutdown");
 
                         let timeout = if let Some(delay) = delay.take() {
@@ -176,7 +176,7 @@ impl Future for WriteTask {
                         this.st = IoWriteState::Shutdown(timeout, Shutdown::None);
                         self.poll(cx)
                     }
-                    Poll::Ready(WriteStatus::Terminate) => {
+                    WriteStatus::Terminate => {
                         log::trace!("write task is instructed to terminate");
 
                         if !matches!(
@@ -191,7 +191,6 @@ impl Future for WriteTask {
                         this.state.close(None);
                         Poll::Ready(())
                     }
-                    Poll::Pending => Poll::Pending,
                 }
             }
             IoWriteState::Shutdown(ref mut delay, ref mut st) => {

ntex/Cargo.toml

@@ -58,7 +58,7 @@ ntex-util = "0.3.4"
 ntex-bytes = "0.1.21"
 ntex-h2 = "0.4.4"
 ntex-rt = "0.4.10"
-ntex-io = "0.3.6"
+ntex-io = "0.3.7"
 ntex-tls = "0.3.2"
 ntex-tokio = { version = "0.3.1", optional = true }
 ntex-glommio = { version = "0.3.0", optional = true }