diff options
author | Sven Gothel <[email protected]> | 2010-10-14 21:30:14 +0200 |
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committer | Sven Gothel <[email protected]> | 2010-10-14 21:30:14 +0200 |
commit | 1c7f8f8dafe0252afbb0e2701687210814b56793 (patch) | |
tree | 99e9830d5b57ab55fc109f30f9196dff6131b810 /src/java/com/jogamp/common/util/locks | |
parent | 52dcea28906b3e61ef44595399e525dd5169c014 (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.java | 77 | ||||
-rw-r--r-- | src/java/com/jogamp/common/util/locks/LockExt.java | 50 | ||||
-rw-r--r-- | src/java/com/jogamp/common/util/locks/RecursiveLock.java | 237 |
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()); + } + } + } +} + |