* Introduce Java 8 Unsafe intrinsics in LogAdder (lock addq and lock xchg)

* Introduce atomic variant of LongAdder::sumThenReset -> LongAdder::sumAndReset
* Remove LongMaxUpdater in favor to AtomicLongMaxUpdater

1 files changed, 40 insertions, 0 deletions

diff --git a/kamon-core/src/main/scala/kamon/util/AtomicLongMaxUpdater.scala b/kamon-core/src/main/scala/kamon/util/AtomicLongMaxUpdater.scala
new file mode 100644
index 00000000..36c01c83
--- /dev/null
+++ b/kamon-core/src/main/scala/kamon/util/AtomicLongMaxUpdater.scala
@@ -0,0 +1,40 @@
+/* =========================================================================================
+ * Copyright © 2013-2017 the kamon project <http://kamon.io/>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+
+package kamon.util
+
+import java.util.concurrent.atomic.AtomicLong
+
+import scala.annotation.tailrec
+
+class AtomicLongMaxUpdater(value:AtomicLong) {
+
+  def update(newMax:Long):Unit = {
+    @tailrec def compare():Long = {
+      val currentMax = value.get()
+      if(newMax > currentMax) if (!value.compareAndSet(currentMax, newMax)) compare() else newMax
+      else currentMax
+    }
+    compare()
+  }
+
+  def maxThenReset(newValue:Long): Long =
+    value.getAndSet(newValue)
+}
+
+object AtomicLongMaxUpdater {
+  def apply(): AtomicLongMaxUpdater =
+    new AtomicLongMaxUpdater(new AtomicLong(0))
+}
\ No newline at end of file