removed locks from bitstate

fair-acc · Sep 22, 2023 · 24768c2 · 24768c2
1 parent bf17521
commit 24768c2
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Showing 2 changed files with 30 additions and 40 deletions.
diff --git a/chartfx-dataset/src/main/java/io/fair_acc/dataset/events/BitState.java b/chartfx-dataset/src/main/java/io/fair_acc/dataset/events/BitState.java
@@ -306,8 +306,6 @@ public static StringBuilder appendStackTrace(StringBuilder builder, int from, in
     private static final int DEFAULT_MIN_STACK_TRACE = 6;
     private static final int DEFAULT_MAX_STACK_TRACE = 25;
 
-    public abstract void waitForFlag();
-
     private static class FilteredListener implements StateListener {
 
         private FilteredListener(int filter, StateListener listener) {
@@ -379,11 +377,6 @@ public int clear(final int bits) {
             return previous;
         }
 
-        @Override
-        public void waitForFlag() {
-            throw new IllegalStateException("cannot wait on single threaded bitstate");
-        }
-
         @Override
         public int getBits() {
             return state;
@@ -402,7 +395,6 @@ protected static class MultiThreadedBitState extends BitState {
         protected MultiThreadedBitState(Object source, int filter, int initial) {
             super(source, filter);
             state.set(initial);
-            //state.notifyAll();
         }
 
         @Override
@@ -413,12 +405,7 @@ public int setDirtyAndGetDelta(int bits) {
                 final int oldState = getBits();
                 final int newState = oldState | bits;
                 final int delta = (oldState ^ newState);
-                if (delta == 0) {
-                    return delta;
-                } else if ( state.compareAndSet(oldState, oldState | bits)) {
-                    synchronized (state) {
-                        state.notifyAll();
-                    }
+                if (oldState == newState || state.compareAndSet(oldState, newState)) {
                     return delta;
                 }
             }
@@ -427,13 +414,10 @@ public int setDirtyAndGetDelta(int bits) {
         @Override
         public int clear(int bits) {
             while (true) {
-                final int current = getBits();
-                final int newState = current & ~bits;
-                if (state.compareAndSet(current, newState)) {
-                    synchronized (state) {
-                        state.notifyAll();
-                    }
-                    return current;
+                final int oldState = getBits();
+                final int newState = oldState & ~bits;
+                if (oldState == newState || state.compareAndSet(oldState, newState)) {
+                    return oldState;
                 }
             }
         }
@@ -443,17 +427,6 @@ public int getBits() {
             return state.get();
         }
 
-        @Override
-        public void waitForFlag() { // todo check if/where lock is needed
-            while (state.get() == 0) {
-                try {
-                    synchronized (state) {
-                        state.wait();
-                    }
-                } catch (InterruptedException ignored) { }
-            }
-        }
-
         private final AtomicInteger state = new AtomicInteger();
     }
 

diff --git a/chartfx-dataset/src/main/java/io/fair_acc/dataset/events/ThreadEventProcessor.java b/chartfx-dataset/src/main/java/io/fair_acc/dataset/events/ThreadEventProcessor.java
@@ -21,8 +21,9 @@ public class ThreadEventProcessor implements EventProcessor, Runnable {
     private static final AtomicReference<ThreadEventProcessor> INSTANCE = new AtomicReference<>();
     private static EventProcessor userInstance;
 
-    private final BitState localState = BitState.initDirty(this, ChartBits.DataSetMask);
-    private final BitState stateRoot = BitState.initDirtyMultiThreaded(this, ChartBits.DataSetMask);
+    private final Object changeLock = new Object();
+    private final BitState state = BitState.initDirtyMultiThreaded(this, ChartBits.DataSetMask)
+            .addChangeListener((src, bits) -> notifyChanged());
     private final List<Pair<BitState, Runnable>> actions = new CopyOnWriteArrayList<>();
 
     public static EventProcessor getUserInstance() {
@@ -58,8 +59,8 @@ public static ThreadEventProcessor getInstance() {
     public void run() {
         //noinspection InfiniteLoopStatement
         while (true) {
-            localState.setDirty(stateRoot.clear());
-            if (localState.isDirty()) {
+            boolean isDirty = state.clear() != 0;
+            if (isDirty) {
                 for (final var action : actions) {
                     if (action.getLeft().isDirty(ChartBits.DataSetMask)) {
                         action.getLeft().clear();
@@ -69,19 +70,35 @@ public void run() {
                     }
                 }
             }
-            localState.clear();
-            stateRoot.waitForFlag();
             // Todo: add optional rate limiting
+            waitForChanges();
+        }
+    }
+
+    private void notifyChanged() {
+        synchronized (changeLock) {
+            changeLock.notifyAll();
+        }
+    }
+
+    private void waitForChanges() {
+        synchronized (changeLock) {
+            if (state.isClean()) {
+                try {
+                    changeLock.wait();
+                } catch (InterruptedException ignored) {
+                }
+            }
         }
     }
 
     public BitState getBitState() {
-        return stateRoot;
+        return state;
     }
 
     @Override
     public void addAction(final BitState obj, final Runnable action) {
-        obj.addInvalidateListener(stateRoot);
+        obj.addInvalidateListener(state);
         actions.add(Pair.of(obj, action));
     }
 }