From 795b14a7b116111574d019bd38aaaa7e33f61120 Mon Sep 17 00:00:00 2001
From: Trustin Lee <trustin@gmail.com>
Date: Tue, 19 Aug 2008 13:50:42 +0000
Subject: [PATCH] Relates issue: NETTY-18 (Performance degradation when
 Channel.write() is called from outside an I/O thread (NIO transport) *
 Extracted NioWorker.WAKEUP_REQUIREMENT_LEVEL to NioProviderMetadata

---
 .../socket/nio/NioProviderMetadata.java       | 53 +++++++++++++++++++
 .../netty/channel/socket/nio/NioWorker.java   | 23 ++------
 2 files changed, 57 insertions(+), 19 deletions(-)
 create mode 100644 src/main/java/org/jboss/netty/channel/socket/nio/NioProviderMetadata.java

diff --git a/src/main/java/org/jboss/netty/channel/socket/nio/NioProviderMetadata.java b/src/main/java/org/jboss/netty/channel/socket/nio/NioProviderMetadata.java
new file mode 100644
index 0000000000..0156864e1a
--- /dev/null
+++ b/src/main/java/org/jboss/netty/channel/socket/nio/NioProviderMetadata.java
@@ -0,0 +1,53 @@
+/*
+ * JBoss, Home of Professional Open Source
+ *
+ * Copyright 2008, Red Hat Middleware LLC, and individual contributors
+ * by the @author tags. See the COPYRIGHT.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+package org.jboss.netty.channel.socket.nio;
+
+/**
+ * Provides information which is specific to a NIO service provider
+ * implementation.
+ *
+ * @author The Netty Project (netty-dev@lists.jboss.org)
+ * @author Trustin Lee (tlee@redhat.com)
+ *
+ * @version $Rev$, $Date$
+ *
+ */
+class NioProviderMetadata {
+
+    /**
+     * FIXME Auto-detect the level
+     *
+     * 0 - no need to wake up to get / set interestOps
+     * 1 - no need to wake up to get interestOps, but need to wake up to set.
+     * 2 - need to wake up to get / set interestOps
+     */
+    static final int CONSTRAINT_LEVEL = 0;
+
+    static {
+        if (CONSTRAINT_LEVEL < 0 || CONSTRAINT_LEVEL > 2) {
+            throw new Error(
+                    "Unexpected wakeup requirement level: " +
+                    CONSTRAINT_LEVEL + ", please report this error.");
+        }
+    }
+}
diff --git a/src/main/java/org/jboss/netty/channel/socket/nio/NioWorker.java b/src/main/java/org/jboss/netty/channel/socket/nio/NioWorker.java
index fef1288121..957d2bc761 100644
--- a/src/main/java/org/jboss/netty/channel/socket/nio/NioWorker.java
+++ b/src/main/java/org/jboss/netty/channel/socket/nio/NioWorker.java
@@ -49,22 +49,7 @@ class NioWorker implements Runnable {
     private static final InternalLogger logger =
         InternalLoggerFactory.getInstance(NioWorker.class);
 
-    /**
-     * FIXME Auto-detect the level
-     *
-     * 0 - no need to wake up to get / set interestOps
-     * 1 - no need to wake up to get interestOps, but need to wake up to set.
-     * 2 - need to wake up to get / set interestOps
-     */
-    private static final int WAKEUP_REQUIREMENT_LEVEL = 0;
-
-    static {
-        if (WAKEUP_REQUIREMENT_LEVEL < 0 || WAKEUP_REQUIREMENT_LEVEL > 2) {
-            throw new Error(
-                    "Unexpected wakeup requirement level: " +
-                    WAKEUP_REQUIREMENT_LEVEL + ", please report this error.");
-        }
-    }
+    private static final int CONSTRAINT_LEVEL = NioProviderMetadata.CONSTRAINT_LEVEL;
 
     private final int bossId;
     private final int id;
@@ -379,7 +364,7 @@ class NioWorker implements Runnable {
         int interestOps;
         boolean changed = false;
         if (opWrite) {
-            switch (WAKEUP_REQUIREMENT_LEVEL) {
+            switch (CONSTRAINT_LEVEL) {
             case 0:
                 interestOps = key.interestOps();
                 if ((interestOps & SelectionKey.OP_WRITE) == 0) {
@@ -429,7 +414,7 @@ class NioWorker implements Runnable {
                 throw new Error();
             }
         } else {
-            switch (WAKEUP_REQUIREMENT_LEVEL) {
+            switch (CONSTRAINT_LEVEL) {
             case 0:
                 interestOps = key.interestOps();
                 if ((interestOps & SelectionKey.OP_WRITE) != 0) {
@@ -542,7 +527,7 @@ class NioWorker implements Runnable {
 
         boolean changed = false;
         try {
-            switch (WAKEUP_REQUIREMENT_LEVEL) {
+            switch (CONSTRAINT_LEVEL) {
             case 0:
                 if (key.interestOps() != interestOps) {
                     key.interestOps(interestOps);