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Commit 15d762e6 authored by Tobias Pietzsch's avatar Tobias Pietzsch
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Moved Entry.loaded flags to Entry.ref.loaded 

This allows to drop the "V extends VolatileCacheValue" requirement without
running into concurrent modification problems. (hopefully...)
parent 49da56bd
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src/main/java/bdv/cache/revised/WeakRefVolatileCache.java
+ 46
− 35
View file @ 15d762e6
...@@ -8,13 +8,12 @@ import java.util.concurrent.ConcurrentHashMap; ...@@ -8,13 +8,12 @@ import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutionException;
import bdv.cache.CacheHints; import bdv.cache.CacheHints;
import bdv.cache.VolatileCacheValue;
import bdv.cache.iotiming.CacheIoTiming; import bdv.cache.iotiming.CacheIoTiming;
import bdv.cache.iotiming.IoStatistics; import bdv.cache.iotiming.IoStatistics;
import bdv.cache.iotiming.IoTimeBudget; import bdv.cache.iotiming.IoTimeBudget;
import bdv.cache.util.BlockingFetchQueues; import bdv.cache.util.BlockingFetchQueues;
public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements VolatileCache< K, V > public class WeakRefVolatileCache< K, V > implements VolatileCache< K, V >
{ {
final ConcurrentHashMap< K, Entry > map = new ConcurrentHashMap<>(); final ConcurrentHashMap< K, Entry > map = new ConcurrentHashMap<>();
...@@ -36,10 +35,20 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -36,10 +35,20 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
{ {
private final Entry entry; private final Entry entry;
public CacheWeakReference( final V referent, final Entry entry ) final int loaded;
public CacheWeakReference( final V referent )
{
super( referent );
entry = null;
loaded = NOTLOADED;
}
public CacheWeakReference( final V referent, final Entry entry, final int loaded )
{ {
super( referent, queue ); super( referent, queue );
this.entry = entry; this.entry = entry;
this.loaded = loaded;
} }
public void clean() public void clean()
...@@ -57,11 +66,9 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -57,11 +66,9 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
final class Entry final class Entry
{ {
private WeakReference< V > ref;
final K key; final K key;
int loaded; CacheWeakReference ref;
long enqueueFrame; long enqueueFrame;
...@@ -71,8 +78,7 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -71,8 +78,7 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
{ {
this.key = key; this.key = key;
this.loader = loader; this.loader = loader;
this.ref = new WeakReference<>( null ); this.ref = new CacheWeakReference( null );
this.loaded = NOTLOADED;
this.enqueueFrame = -1; this.enqueueFrame = -1;
} }
...@@ -83,15 +89,13 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -83,15 +89,13 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
public void setInvalid( final V value ) public void setInvalid( final V value )
{ {
loaded = INVALID; ref = new CacheWeakReference( value, this, INVALID );
ref = new CacheWeakReference( value, this );
} }
// Precondition: caller must hold lock on this. // Precondition: caller must hold lock on this.
public void setValid( final V value ) public void setValid( final V value )
{ {
loaded = VALID; ref = new CacheWeakReference( value, this, VALID );
ref = new CacheWeakReference( value, this );
loader = null; loader = null;
enqueueFrame = Long.MAX_VALUE; enqueueFrame = Long.MAX_VALUE;
notifyAll(); notifyAll();
...@@ -111,8 +115,9 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -111,8 +115,9 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
if ( entry == null ) if ( entry == null )
return null; return null;
final V v = entry.getValue(); final CacheWeakReference ref = entry.ref;
if ( v != null && v.isValid() ) final V v = ref.get();
if ( v != null && ref.loaded == VALID )
return v; return v;
cleanUp( 50 ); cleanUp( 50 );
...@@ -147,8 +152,9 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -147,8 +152,9 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
*/ */
final Entry entry = map.computeIfAbsent( key, k -> new Entry( k, loader ) ); final Entry entry = map.computeIfAbsent( key, k -> new Entry( k, loader ) );
V v = entry.getValue(); final CacheWeakReference ref = entry.ref;
if ( v != null && v.isValid() ) V v = ref.get();
if ( v != null && ref.loaded == VALID )
return v; return v;
cleanUp( 50 ); cleanUp( 50 );
...@@ -247,7 +253,7 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -247,7 +253,7 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
if ( v != null ) if ( v != null )
return v; return v;
if ( entry.loaded != NOTLOADED ) if ( entry.ref.loaded != NOTLOADED )
{ {
map.remove( entry.key, entry ); map.remove( entry.key, entry );
return null; return null;
...@@ -270,14 +276,15 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -270,14 +276,15 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
{ {
synchronized( entry ) synchronized( entry )
{ {
V v = entry.getValue(); final CacheWeakReference ref = entry.ref;
if ( v == null && entry.loaded != NOTLOADED ) V v = ref.get();
if ( v == null && ref.loaded != NOTLOADED )
{ {
map.remove( entry.key, entry ); map.remove( entry.key, entry );
return null; return null;
} }
if ( entry.loaded == VALID ) // v.isValid() if ( ref.loaded == VALID )
return v; return v;
final V vl = backingCache.getIfPresent( entry.key ); final V vl = backingCache.getIfPresent( entry.key );
...@@ -287,7 +294,7 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -287,7 +294,7 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
return vl; return vl;
} }
if ( entry.loaded == NOTLOADED ) if ( ref.loaded == NOTLOADED )
{ {
v = entry.loader.createInvalid(); v = entry.loader.createInvalid();
entry.setInvalid( v ); entry.setInvalid( v );
...@@ -302,15 +309,16 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -302,15 +309,16 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
{ {
synchronized( entry ) synchronized( entry )
{ {
V v = entry.getValue(); CacheWeakReference ref = entry.ref;
if ( v == null && entry.loaded != NOTLOADED ) V v = ref.get();
if ( v == null && ref.loaded != NOTLOADED )
{ {
// printEntryCollected( "map.remove getBudgeted 1", entry ); // printEntryCollected( "map.remove getBudgeted 1", entry );
map.remove( entry.key, entry ); map.remove( entry.key, entry );
return null; return null;
} }
if ( entry.loaded == VALID ) // v.isValid() if ( ref.loaded == VALID )
return v; return v;
enqueue( entry, hints ); enqueue( entry, hints );
...@@ -335,10 +343,11 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -335,10 +343,11 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
budget.use( t, priority ); budget.use( t, priority );
} }
v = entry.getValue(); ref = entry.ref;
v = ref.get();
if ( v == null ) if ( v == null )
{ {
if ( entry.loaded == NOTLOADED ) if ( ref.loaded == NOTLOADED )
{ {
v = entry.loader.createInvalid(); v = entry.loader.createInvalid();
entry.setInvalid( v ); entry.setInvalid( v );
...@@ -360,15 +369,16 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -360,15 +369,16 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
VolatileLoader< ? extends V > loader; VolatileLoader< ? extends V > loader;
synchronized( entry ) synchronized( entry )
{ {
final V v = entry.getValue(); final CacheWeakReference ref = entry.ref;
if ( v == null && entry.loaded != NOTLOADED ) final V v = ref.get();
if ( v == null && ref.loaded != NOTLOADED )
{ {
// printEntryCollected( "map.remove getBlocking 1", entry ); // printEntryCollected( "map.remove getBlocking 1", entry );
map.remove( entry.key, entry ); map.remove( entry.key, entry );
return null; return null;
} }
if ( entry.loaded == VALID ) // v.isValid() if ( ref.loaded == VALID ) // v.isValid()
return v; return v;
loader = entry.loader; loader = entry.loader;
...@@ -376,15 +386,16 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -376,15 +386,16 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
final V vl = backingCache.get( entry.key, loader ); final V vl = backingCache.get( entry.key, loader );
synchronized( entry ) synchronized( entry )
{ {
final V v = entry.getValue(); final CacheWeakReference ref = entry.ref;
if ( v == null && entry.loaded != NOTLOADED ) final V v = ref.get();
if ( v == null && ref.loaded != NOTLOADED )
{ {
// printEntryCollected( "map.remove getBlocking 2", entry ); // printEntryCollected( "map.remove getBlocking 2", entry );
map.remove( entry.key, entry ); map.remove( entry.key, entry );
return null; return null;
} }
if ( entry.loaded == VALID ) // v.isValid() if ( ref.loaded == VALID ) // v.isValid()
return v; return v;
// entry.loaded == INVALID // entry.loaded == INVALID
...@@ -416,11 +427,11 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements ...@@ -416,11 +427,11 @@ public class WeakRefVolatileCache< K, V extends VolatileCacheValue > implements
*/ */
private synchronized void printEntryCollected( final String title, final Entry entry ) private synchronized void printEntryCollected( final String title, final Entry entry )
{ {
final String state = entry.loaded == 0 final String state = entry.ref.loaded == 0
? "NOTLOADED" ? "NOTLOADED"
: ( entry.loaded == 1 : ( entry.ref.loaded == 1
? "INVALID" ? "INVALID"
: ( entry.loaded == 2 : ( entry.ref.loaded == 2
? "VALID" ? "VALID"
: "UNDEFINED" ) ); : "UNDEFINED" ) );
System.out.println( title + " entry.loaded = " + state ); System.out.println( title + " entry.loaded = " + state );
......
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