Revert "opt: improve the event-driven logic"

This reverts commit bc75be6.

connection_unix.go

@@ -109,7 +109,7 @@ func (c *conn) read() ([]byte, error) {
 	return c.codec.Decode(c)
 }
 
-func (c *conn) write(buf []byte, writeable bool) (err error) {
+func (c *conn) write(buf []byte) (err error) {
 	var outFrame []byte
 	if outFrame, err = c.codec.Encode(c, buf); err != nil {
 		return
@@ -120,11 +120,6 @@ func (c *conn) write(buf []byte, writeable bool) (err error) {
 		_, _ = c.outboundBuffer.Write(outFrame)
 		return
 	}
-	if !writeable {
-		_, _ = c.outboundBuffer.Write(outFrame)
-		err = c.loop.poller.ModReadWrite(c.fd)
-		return
-	}
 
 	var n int
 	if n, err = unix.Write(c.fd, outFrame); err != nil {
@@ -148,7 +143,7 @@ func (c *conn) asyncWrite(itf interface{}) error {
 	if !c.opened {
 		return nil
 	}
-	return c.write(itf.([]byte), true)
+	return c.write(itf.([]byte))
 }
 
 func (c *conn) sendTo(buf []byte) error {

eventloop_unix.go

@@ -153,10 +153,7 @@ func (el *eventloop) loopOpen(c *conn) error {
 	return el.handleAction(c, action)
 }
 
-func (el *eventloop) loopRead(c *conn, writeable bool) error {
-	if writeable && !c.outboundBuffer.IsEmpty() {
-		return nil
-	}
+func (el *eventloop) loopRead(c *conn) error {
 	n, err := unix.Read(c.fd, el.buffer)
 	if n == 0 || err != nil {
 		if err == unix.EAGAIN {
@@ -173,7 +170,7 @@ func (el *eventloop) loopRead(c *conn, writeable bool) error {
 			// Encode data and try to write it back to the client, this attempt is based on a fact:
 			// a client socket waits for the response data after sending request data to the server,
 			// which makes the client socket writable.
-			if err = c.write(out, writeable); err != nil {
+			if err = c.write(out); err != nil {
 				return err
 			}
 		}
@@ -268,7 +265,7 @@ func (el *eventloop) loopWake(c *conn) error {
 
 	out, action := el.eventHandler.React(nil, c)
 	if out != nil {
-		if err := c.write(out, true); err != nil {
+		if err := c.write(out); err != nil {
 			return err
 		}
 	}

loop_bsd.go

@@ -32,7 +32,7 @@ func (el *eventloop) handleEvent(fd int, filter int16) (err error) {
 		case netpoll.EVFilterWrite:
 			err = el.loopWrite(c)
 		case netpoll.EVFilterRead:
-			err = el.loopRead(c, false)
+			err = el.loopRead(c)
 		}
 		return
 	}

loop_linux.go

@@ -47,8 +47,8 @@ func (el *eventloop) handleEvent(fd int, ev uint32) error {
 		// resulting in that it won't receive any responses before the server read all data from client,
 		// in which case if the socket send buffer is full, we need to let it go and continue reading the data
 		// to prevent blocking forever.
-		if ev&netpoll.InEvents != 0 {
-			return el.loopRead(c, ev&netpoll.OutEvents != 0)
+		if ev&netpoll.InEvents != 0 && (ev&netpoll.OutEvents == 0 || c.outboundBuffer.IsEmpty()) {
+			return el.loopRead(c)
 		}
 		return nil
 	}

reactor_bsd.go

@@ -64,7 +64,7 @@ func (svr *server) activateSubReactor(el *eventloop, lockOSThread bool) {
 			case netpoll.EVFilterWrite:
 				err = el.loopWrite(c)
 			case netpoll.EVFilterRead:
-				err = el.loopRead(c, false)
+				err = el.loopRead(c)
 			}
 		}
 		return

reactor_linux.go

@@ -79,8 +79,8 @@ func (svr *server) activateSubReactor(el *eventloop, lockOSThread bool) {
 			// resulting in that it won't receive any responses before the server reads all data from client,
 			// in which case if the server socket send buffer is full, we need to let it go and continue reading
 			// the data to prevent blocking forever.
-			if ev&netpoll.InEvents != 0 {
-				return el.loopRead(c, ev&netpoll.OutEvents != 0)
+			if ev&netpoll.InEvents != 0 && (ev&netpoll.OutEvents == 0 || c.outboundBuffer.IsEmpty()) {
+				return el.loopRead(c)
 			}
 		}
 		return nil