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authorSven Gothel <[email protected]>2010-10-14 21:30:14 +0200
committerSven Gothel <[email protected]>2010-10-14 21:30:14 +0200
commit1c7f8f8dafe0252afbb0e2701687210814b56793 (patch)
tree99e9830d5b57ab55fc109f30f9196dff6131b810 /src/java/com/jogamp/common/util/locks
parent52dcea28906b3e61ef44595399e525dd5169c014 (diff)
Moved locking to: com.jogamp.common.util.locks ; Better abstraction ; Misc changes
Diffstat (limited to 'src/java/com/jogamp/common/util/locks')
-rw-r--r--src/java/com/jogamp/common/util/locks/Lock.java77
-rw-r--r--src/java/com/jogamp/common/util/locks/LockExt.java50
-rw-r--r--src/java/com/jogamp/common/util/locks/RecursiveLock.java237
3 files changed, 364 insertions, 0 deletions
diff --git a/src/java/com/jogamp/common/util/locks/Lock.java b/src/java/com/jogamp/common/util/locks/Lock.java
new file mode 100644
index 0000000..7065ff8
--- /dev/null
+++ b/src/java/com/jogamp/common/util/locks/Lock.java
@@ -0,0 +1,77 @@
+/**
+ * Copyright 2010 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of
+ * conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ * of conditions and the following disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+
+package com.jogamp.common.util.locks;
+
+import com.jogamp.common.impl.Debug;
+import java.security.AccessController;
+
+/**
+ * Specifying a thread blocking lock implementation
+ */
+public interface Lock {
+
+ /** Enable via the property <code>jogamp.debug.Lock</code> */
+ public static final boolean DEBUG = Debug.debug("Lock");
+
+ /** Defines the default {@link #TIMEOUT} value */
+ public static final long DEFAULT_TIMEOUT = 5000; // 5s default timeout
+
+ /**
+ * Defines the <code>TIMEOUT</code> for {@link #lock()} in ms,
+ * and defaults to {@link #DEFAULT_TIMEOUT}.<br>
+ * It can be overriden via the system property <code>jogamp.common.utils.locks.Lock.timeout</code>.
+ */
+ public static final long TIMEOUT = Debug.getLongProperty("jogamp.common.utils.locks.Lock.timeout", true, AccessController.getContext(), DEFAULT_TIMEOUT);
+
+ /**
+ * Blocking until the lock is acquired by this Thread or {@link #TIMEOUT} is reached.
+ *
+ * @throws RuntimeException in case of {@link #TIMEOUT}
+ */
+ void lock() throws RuntimeException;
+
+ /**
+ * Blocking until the lock is acquired by this Thread or <code>maxwait</code> in ms is reached.
+ *
+ * @param maxwait Maximum time in ms to wait to acquire the lock. If this value is zero,
+ * the call returns immediately either without being able
+ * to acquire the lock, or with acquiring the lock directly while ignoring any scheduling order.
+ * @return true if the lock has been acquired within <code>maxwait</code>, otherwise false
+ *
+ * @throws RuntimeException in case of {@link #TIMEOUT}
+ */
+ boolean tryLock(long maxwait) throws RuntimeException;
+
+ /**
+ * Unblocking.
+ *
+ * @throws RuntimeException in case the lock is not acquired by this thread.
+ */
+ void unlock() throws RuntimeException;
+}
diff --git a/src/java/com/jogamp/common/util/locks/LockExt.java b/src/java/com/jogamp/common/util/locks/LockExt.java
new file mode 100644
index 0000000..42a01c6
--- /dev/null
+++ b/src/java/com/jogamp/common/util/locks/LockExt.java
@@ -0,0 +1,50 @@
+/**
+ * Copyright 2010 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of
+ * conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ * of conditions and the following disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+
+package com.jogamp.common.util.locks;
+
+/**
+ * Extending the {@link Lock} features with convenient functionality.
+ */
+public interface LockExt extends Lock {
+
+ /**
+ * @return the Thread owning this lock if locked, otherwise null
+ */
+ Thread getOwner();
+
+ boolean isLocked();
+
+ boolean isLockedByOtherThread();
+
+ boolean isOwner();
+
+ boolean isOwner(Thread thread);
+
+ void validateLocked();
+}
diff --git a/src/java/com/jogamp/common/util/locks/RecursiveLock.java b/src/java/com/jogamp/common/util/locks/RecursiveLock.java
new file mode 100644
index 0000000..010467b
--- /dev/null
+++ b/src/java/com/jogamp/common/util/locks/RecursiveLock.java
@@ -0,0 +1,237 @@
+/**
+ * Copyright 2010 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of
+ * conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ * of conditions and the following disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+
+package com.jogamp.common.util.locks;
+
+import com.jogamp.common.impl.Debug;
+import java.security.AccessController;
+
+import java.util.LinkedList;
+
+/**
+ * Reentrance locking toolkit, impl a complete fair FIFO scheduler
+ */
+public class RecursiveLock implements LockExt {
+
+ static class SyncData {
+ // owner of the lock
+ Thread owner = null;
+ // lock recursion
+ int recursionCount = 0;
+ // stack trace of the lock, only used if DEBUG
+ Throwable lockedStack = null;
+ // waiting thread queue
+ LinkedList threadQueue = new LinkedList();
+ // flag signaling unlock has woken up a waiting thread
+ boolean signaled = false;
+ }
+ private SyncData sdata = new SyncData(); // synchronized (flow/mem) mutable access
+
+ private static final boolean TRACE_LOCK = Debug.isPropertyDefined("jogamp.debug.Lock.TraceLock", true, AccessController.getContext());
+
+ public RecursiveLock() {
+ }
+
+ /**
+ * Returns the Throwable instance generated when this lock was taken the 1st time
+ * and if {@link com.jogamp.common.util.locks.Lock#DEBUG} is turned on, otherwise it returns always <code>null</code>.
+ * @see com.jogamp.common.util.locks.Lock#DEBUG
+ */
+ public final Throwable getLockedStack() {
+ synchronized(sdata) {
+ return sdata.lockedStack;
+ }
+ }
+
+ public final Thread getOwner() {
+ synchronized(sdata) {
+ return sdata.owner;
+ }
+ }
+
+ public final boolean isOwner() {
+ return isOwner(Thread.currentThread());
+ }
+
+ public final boolean isOwner(Thread thread) {
+ synchronized(sdata) {
+ return sdata.owner == thread ;
+ }
+ }
+
+ public final boolean isLocked() {
+ synchronized(sdata) {
+ return null != sdata.owner;
+ }
+ }
+
+ public final boolean isLockedByOtherThread() {
+ synchronized(sdata) {
+ return null != sdata.owner && Thread.currentThread() != sdata.owner ;
+ }
+ }
+
+ public final int getRecursionCount() {
+ synchronized(sdata) {
+ return sdata.recursionCount;
+ }
+ }
+
+ public final void validateLocked() {
+ synchronized(sdata) {
+ if ( null == sdata.owner ) {
+ throw new RuntimeException(Thread.currentThread()+": Not locked");
+ }
+ if ( Thread.currentThread() != sdata.owner ) {
+ if(null!=sdata.lockedStack) {
+ sdata.lockedStack.printStackTrace();
+ }
+ throw new RuntimeException(Thread.currentThread()+": Not owner, owner is "+sdata.owner);
+ }
+ }
+ }
+
+ public final void lock() {
+ synchronized(sdata) {
+ if(!tryLock(TIMEOUT)) {
+ if(null!=sdata.lockedStack) {
+ sdata.lockedStack.printStackTrace();
+ }
+ throw new RuntimeException("Waited "+TIMEOUT+"ms for: "+sdata.owner+" - "+Thread.currentThread()+", with recursionCount "+sdata.recursionCount+", lock: "+this+", qsz "+sdata.threadQueue.size());
+ }
+ }
+ }
+
+ public boolean tryLock(long maxwait) {
+ synchronized(sdata) {
+ Thread cur = Thread.currentThread();
+ if(TRACE_LOCK) {
+ Throwable tt = new Throwable("LOCK 0 ["+this+"], recursions "+sdata.recursionCount+", cur "+cur+", owner "+sdata.owner);
+ tt.printStackTrace();
+ }
+ if (sdata.owner == cur) {
+ ++sdata.recursionCount;
+ if(TRACE_LOCK) {
+ System.err.println("+++ LOCK 2 ["+this+"], recursions "+sdata.recursionCount+", "+cur);
+ }
+ return true;
+ }
+
+ if ( sdata.owner != null ||
+ 0 < maxwait && ( sdata.signaled || sdata.threadQueue.size() > 0 ) ) {
+
+ if ( 0 >= maxwait ) {
+ // implies 'sdata.owner != null': locked by other thread
+ // no waiting requested, bail out right away
+ return false;
+ }
+
+ boolean timedOut = false;
+ do {
+ sdata.threadQueue.addFirst(cur); // should only happen once
+ try {
+ sdata.wait(maxwait);
+ timedOut = sdata.threadQueue.remove(cur); // TIMEOUT if not already removed by unlock
+ } catch (InterruptedException e) {
+ if(!sdata.signaled) {
+ // theoretically we could stay in the loop,
+ // in case the interrupt wasn't issued by unlock,
+ // hence the re-enqueue
+ sdata.threadQueue.remove(cur);
+ if(TRACE_LOCK) {
+ System.err.println("XXX LOCK - ["+this+"], recursions "+sdata.recursionCount+", "+cur);
+ }
+ }
+ }
+ } while (null != sdata.owner && !timedOut) ;
+
+ sdata.signaled = false;
+
+ if(timedOut || null != sdata.owner) {
+ return false;
+ }
+
+ if(TRACE_LOCK) {
+ System.err.println("+++ LOCK 3 ["+this+"], recursions "+sdata.recursionCount+", qsz "+sdata.threadQueue.size()+", "+cur);
+ }
+ } else if(TRACE_LOCK) {
+ System.err.println("+++ LOCK 1 ["+this+"], recursions "+sdata.recursionCount+", qsz "+sdata.threadQueue.size()+", "+cur);
+ }
+
+ sdata.owner = cur;
+ if(DEBUG) {
+ sdata.lockedStack = new Throwable("Previously locked by "+sdata.owner+", lock: "+this);
+ }
+ return true;
+ }
+ }
+
+
+ public final void unlock() {
+ unlock(null);
+ }
+
+ public final void unlock(Runnable taskAfterUnlockBeforeNotify) {
+ synchronized(sdata) {
+ validateLocked();
+
+ if (sdata.recursionCount > 0) {
+ --sdata.recursionCount;
+ if(TRACE_LOCK) {
+ System.err.println("--- LOCK 1 ["+this+"], recursions "+sdata.recursionCount+", "+Thread.currentThread());
+ }
+ return;
+ }
+ sdata.owner = null;
+ sdata.lockedStack = null;
+ if(null!=taskAfterUnlockBeforeNotify) {
+ taskAfterUnlockBeforeNotify.run();
+ }
+
+ int qsz = sdata.threadQueue.size();
+ if(qsz > 0) {
+ Thread parkedThread = (Thread) sdata.threadQueue.removeLast();
+ if(TRACE_LOCK) {
+ System.err.println("--- LOCK X ["+this+"], recursions "+sdata.recursionCount+
+ ", "+Thread.currentThread()+", irq "+(qsz-1)+": "+parkedThread);
+ }
+ sdata.signaled = true;
+ if(qsz==1) {
+ // fast path, just one waiting thread
+ sdata.notify();
+ } else {
+ // signal the oldest one ..
+ parkedThread.interrupt(); // Propagate SecurityException if it happens
+ }
+ } else if(TRACE_LOCK) {
+ System.err.println("--- LOCK X ["+this+"], recursions "+sdata.recursionCount+", "+Thread.currentThread());
+ }
+ }
+ }
+}
+