X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=blobdiff_plain;f=yang%2Fyang-parser-reactor%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fyangtools%2Fyang%2Fparser%2Fstmt%2Freactor%2FReactorStmtCtx.java;h=a32710dcd950912c0839dd53270676d54f069dcd;hb=refs%2Fchanges%2F86%2F95886%2F5;hp=421d9e806b28779931db8e405dc47712ae04d174;hpb=d0340ae67cb7a29fb4fd95c52e30cfcd7bd7a54f;p=yangtools.git diff --git a/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ReactorStmtCtx.java b/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ReactorStmtCtx.java index 421d9e806b..a32710dcd9 100644 --- a/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ReactorStmtCtx.java +++ b/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ReactorStmtCtx.java @@ -7,6 +7,7 @@ */ package org.opendaylight.yangtools.yang.parser.stmt.reactor; +import static com.google.common.base.Preconditions.checkArgument; import static com.google.common.base.Verify.verify; import com.google.common.base.MoreObjects; @@ -14,19 +15,38 @@ import com.google.common.base.MoreObjects.ToStringHelper; import com.google.common.base.VerifyException; import java.util.Collection; import java.util.Map; +import java.util.Optional; +import java.util.Set; import org.eclipse.jdt.annotation.NonNull; import org.eclipse.jdt.annotation.Nullable; +import org.opendaylight.yangtools.yang.common.QName; +import org.opendaylight.yangtools.yang.common.QNameModule; import org.opendaylight.yangtools.yang.common.YangVersion; +import org.opendaylight.yangtools.yang.model.api.SchemaPath; import org.opendaylight.yangtools.yang.model.api.meta.DeclaredStatement; import org.opendaylight.yangtools.yang.model.api.meta.EffectiveStatement; -import org.opendaylight.yangtools.yang.model.api.meta.IdentifierNamespace; import org.opendaylight.yangtools.yang.model.api.meta.StatementDefinition; +import org.opendaylight.yangtools.yang.model.api.stmt.AugmentStatement; +import org.opendaylight.yangtools.yang.model.api.stmt.ConfigEffectiveStatement; +import org.opendaylight.yangtools.yang.model.api.stmt.DeviationStatement; +import org.opendaylight.yangtools.yang.model.api.stmt.RefineStatement; +import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier; +import org.opendaylight.yangtools.yang.model.api.stmt.UsesStatement; import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier; +import org.opendaylight.yangtools.yang.parser.spi.meta.CopyType; +import org.opendaylight.yangtools.yang.parser.spi.meta.EffectiveStmtCtx.Current; +import org.opendaylight.yangtools.yang.parser.spi.meta.InferenceException; import org.opendaylight.yangtools.yang.parser.spi.meta.ModelActionBuilder; import org.opendaylight.yangtools.yang.parser.spi.meta.ModelProcessingPhase; -import org.opendaylight.yangtools.yang.parser.spi.meta.MutableStatement; +import org.opendaylight.yangtools.yang.parser.spi.meta.ModelProcessingPhase.ExecutionOrder; import org.opendaylight.yangtools.yang.parser.spi.meta.NamespaceBehaviour.Registry; +import org.opendaylight.yangtools.yang.parser.spi.meta.ParserNamespace; +import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext; import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext.Mutable; +import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContextUtils; +import org.opendaylight.yangtools.yang.parser.spi.source.SourceException; +import org.opendaylight.yangtools.yang.parser.spi.source.SupportedFeaturesNamespace; +import org.opendaylight.yangtools.yang.parser.spi.source.SupportedFeaturesNamespace.SupportedFeatures; import org.slf4j.Logger; import org.slf4j.LoggerFactory; @@ -38,13 +58,13 @@ import org.slf4j.LoggerFactory; * @param Effective Statement representation */ abstract class ReactorStmtCtx, E extends EffectiveStatement> - extends NamespaceStorageSupport implements Mutable { + extends NamespaceStorageSupport implements Mutable, Current { private static final Logger LOG = LoggerFactory.getLogger(ReactorStmtCtx.class); /** * Substatement refcount tracking. This mechanics deals with retaining substatements for the purposes of * instantiating their lazy copies in InferredStatementContext. It works in concert with {@link #buildEffective()} - * and {@link #buildDeclared()}: declared/effective statement views hold an implicit reference and refcount-based + * and {@link #declared()}: declared/effective statement views hold an implicit reference and refcount-based * sweep is not activated until they are done (or this statement is not {@link #isSupportedToBuildEffective}). * *

@@ -93,8 +113,74 @@ abstract class ReactorStmtCtx, E extends Effec */ private static final int REFCOUNT_SWEPT = Integer.MIN_VALUE; + /** + * Effective instance built from this context. This field as dual types. Under normal circumstances in matches the + * {@link #buildEffective()} instance. If this context is reused, it can be inflated to {@link EffectiveInstances} + * and also act as a common instance reuse site. + */ private @Nullable E effectiveInstance; + // Master flag controlling whether this context can yield an effective statement + // FIXME: investigate the mechanics that are being supported by this, as it would be beneficial if we can get rid + // of this flag -- eliminating the initial alignment shadow used by below gap-filler fields. + private boolean isSupportedToBuildEffective = true; + + // EffectiveConfig mapping + private static final int MASK_CONFIG = 0x03; + private static final int HAVE_CONFIG = 0x04; + // Effective instantiation mechanics for StatementContextBase: if this flag is set all substatements are known not + // change when instantiated. This includes context-independent statements as well as any statements which are + // ignored during copy instantiation. + private static final int ALL_INDEPENDENT = 0x08; + // Flag bit assignments + private static final int IS_SUPPORTED_BY_FEATURES = 0x10; + private static final int HAVE_SUPPORTED_BY_FEATURES = 0x20; + private static final int IS_IGNORE_IF_FEATURE = 0x40; + private static final int HAVE_IGNORE_IF_FEATURE = 0x80; + // Have-and-set flag constants, also used as masks + private static final int SET_SUPPORTED_BY_FEATURES = HAVE_SUPPORTED_BY_FEATURES | IS_SUPPORTED_BY_FEATURES; + private static final int SET_IGNORE_IF_FEATURE = HAVE_IGNORE_IF_FEATURE | IS_IGNORE_IF_FEATURE; + + private static final EffectiveConfig[] EFFECTIVE_CONFIGS; + + static { + final EffectiveConfig[] values = EffectiveConfig.values(); + final int length = values.length; + verify(length == 4, "Unexpected EffectiveConfig cardinality %s", length); + EFFECTIVE_CONFIGS = values; + } + + // Flags for use with SubstatementContext. These are hiding in the alignment shadow created by above boolean and + // hence improve memory layout. + private byte flags; + + // Flag for use by AbstractResumedStatement, ReplicaStatementContext and InferredStatementContext. Each of them + // uses it to indicated a different condition. This is hiding in the alignment shadow created by + // 'isSupportedToBuildEffective'. + // FIXME: move this out once we have JDK15+ + private boolean boolFlag; + + // SchemaPath cache for use with SubstatementContext and InferredStatementContext. This hurts RootStatementContext + // a bit in terms of size -- but those are only a few and SchemaPath is on its way out anyway. + // FIXME: this should become 'QName' + private SchemaPath schemaPath; + + ReactorStmtCtx() { + // Empty on purpose + } + + ReactorStmtCtx(final ReactorStmtCtx original) { + isSupportedToBuildEffective = original.isSupportedToBuildEffective; + boolFlag = original.boolFlag; + flags = original.flags; + } + + // Used by ReplicaStatementContext only + ReactorStmtCtx(final ReactorStmtCtx original, final Void dummy) { + boolFlag = isSupportedToBuildEffective = original.isSupportedToBuildEffective; + flags = original.flags; + } + // // // Common public interface contracts with simple mechanics. Please keep this in one logical block, so we do not end @@ -117,7 +203,7 @@ abstract class ReactorStmtCtx, E extends Effec } @Override - public final YangVersion getRootVersion() { + public final YangVersion yangVersion() { return getRoot().getRootVersionImpl(); } @@ -126,11 +212,6 @@ abstract class ReactorStmtCtx, E extends Effec getRoot().setRootVersionImpl(version); } - @Override - public final void addMutableStmtToSeal(final MutableStatement mutableStatement) { - getRoot().addMutableStmtToSealImpl(mutableStatement); - } - @Override public final void addRequiredSource(final SourceIdentifier dependency) { getRoot().addRequiredSourceImpl(dependency); @@ -141,11 +222,6 @@ abstract class ReactorStmtCtx, E extends Effec getRoot().setRootIdentifierImpl(identifier); } - @Override - public final boolean isEnabledSemanticVersioning() { - return getRoot().isEnabledSemanticVersioningImpl(); - } - @Override public final ModelActionBuilder newInferenceAction(final ModelProcessingPhase phase) { return getRoot().getSourceContext().newInferenceAction(phase); @@ -156,6 +232,65 @@ abstract class ReactorStmtCtx, E extends Effec return definition().getPublicView(); } + @Override + public final Parent effectiveParent() { + return getParentContext(); + } + + @Override + public final QName moduleName() { + final RootStatementContext root = getRoot(); + return QName.create(StmtContextUtils.getRootModuleQName(root), root.getRawArgument()); + } + + @Override + public final EffectiveStatement original() { + return getOriginalCtx().map(StmtContext::buildEffective).orElse(null); + } + + // + // In the next two methods we are looking for an effective statement. If we already have an effective instance, + // defer to it's implementation of the equivalent search. Otherwise we search our substatement contexts. + // + // Note that the search function is split, so as to allow InferredStatementContext to do its own thing first. + // + + @Override + public final > @NonNull Optional findSubstatementArgument( + final @NonNull Class type) { + final E existing = effectiveInstance; + return existing != null ? existing.findFirstEffectiveSubstatementArgument(type) + : findSubstatementArgumentImpl(type); + } + + @Override + public final boolean hasSubstatement(final @NonNull Class> type) { + final E existing = effectiveInstance; + return existing != null ? existing.findFirstEffectiveSubstatement(type).isPresent() : hasSubstatementImpl(type); + } + + // Visible due to InferredStatementContext's override. At this point we do not have an effective instance available. + > @NonNull Optional findSubstatementArgumentImpl( + final @NonNull Class type) { + return allSubstatementsStream() + .filter(ctx -> ctx.isSupportedToBuildEffective() && ctx.producesEffective(type)) + .findAny() + .map(ctx -> (X) ctx.getArgument()); + } + + // Visible due to InferredStatementContext's override. At this point we do not have an effective instance available. + boolean hasSubstatementImpl(final @NonNull Class> type) { + return allSubstatementsStream() + .anyMatch(ctx -> ctx.isSupportedToBuildEffective() && ctx.producesEffective(type)); + } + + @Override + @Deprecated + @SuppressWarnings("unchecked") + public final > StmtContext caerbannog() { + return (StmtContext) this; + } + @Override public final String toString() { return addToStringAttributes(MoreObjects.toStringHelper(this).omitNullValues()).toString(); @@ -179,33 +314,52 @@ abstract class ReactorStmtCtx, E extends Effec // @Override - public final > V getFromNamespace( - final Class<@NonNull N> type, final T key) { + public final > V namespaceItem(final Class<@NonNull N> type, + final T key) { return getBehaviourRegistry().getNamespaceBehaviour(type).getFrom(this, key); } @Override - public final > Map getAllFromNamespace(final Class type) { + public final > Map namespace(final Class<@NonNull N> type) { return getNamespace(type); } @Override - public final > Map getAllFromCurrentStmtCtxNamespace( - final Class type) { + public final > + Map localNamespacePortion(final Class<@NonNull N> type) { return getLocalNamespace(type); } @Override - protected final void checkLocalNamespaceAllowed(final Class> type) { - definition().checkNamespaceAllowed(type); + protected > void onNamespaceElementAdded(final Class type, final K key, + final V value) { + // definition().onNamespaceElementAdded(this, type, key, value); } + /** + * Return the effective statement view of a copy operation. This method may return one of: + *

    + *
  • {@code this}, when the effective view did not change
    • + *
  • an InferredStatementContext, when there is a need for inference-equivalent copy
    • + *
  • {@code null}, when the statement failed to materialize
    • + *
+ * + * @param parent Proposed new parent + * @param type Copy operation type + * @param targetModule New target module + * @return {@link ReactorStmtCtx} holding effective view + */ + abstract @Nullable ReactorStmtCtx asEffectiveChildOf(StatementContextBase parent, CopyType type, + QNameModule targetModule); + @Override - protected > void onNamespaceElementAdded(final Class type, final K key, - final V value) { - // definition().onNamespaceElementAdded(this, type, key, value); + public final ReactorStmtCtx replicaAsChildOf(final Mutable parent) { + checkArgument(parent instanceof StatementContextBase, "Unsupported parent %s", parent); + return replicaAsChildOf((StatementContextBase) parent); } + abstract @NonNull ReplicaStatementContext replicaAsChildOf(@NonNull StatementContextBase parent); + // // // Statement build entry points -- both public and package-private. @@ -218,14 +372,15 @@ abstract class ReactorStmtCtx, E extends Effec return (existing = effectiveInstance) != null ? existing : loadEffective(); } - private E loadEffective() { + private @NonNull E loadEffective() { // Creating an effective statement does not strictly require a declared instance -- there are statements like // 'input', which are implicitly defined. // Our implementation design makes an invariant assumption that buildDeclared() has been called by the time // we attempt to create effective statement: - buildDeclared(); + declared(); - final E ret = effectiveInstance = createEffective(); + final E ret = createEffective(); + effectiveInstance = ret; // we have called createEffective(), substatements are no longer guarded by us. Let's see if we can clear up // some residue. if (refcount == REFCOUNT_NONE) { @@ -236,6 +391,273 @@ abstract class ReactorStmtCtx, E extends Effec abstract @NonNull E createEffective(); + /** + * Walk this statement's copy history and return the statement closest to original which has not had its effective + * statements modified. This statement and returned substatement logically have the same set of substatements, hence + * share substatement-derived state. + * + * @return Closest {@link ReactorStmtCtx} with equivalent effective substatements + */ + abstract @NonNull ReactorStmtCtx unmodifiedEffectiveSource(); + + @Override + public final ModelProcessingPhase getCompletedPhase() { + return ModelProcessingPhase.ofExecutionOrder(executionOrder()); + } + + abstract byte executionOrder(); + + /** + * Try to execute current {@link ModelProcessingPhase} of source parsing. If the phase has already been executed, + * this method does nothing. This must not be called with {@link ExecutionOrder#NULL}. + * + * @param phase to be executed (completed) + * @return true if phase was successfully completed + * @throws SourceException when an error occurred in source parsing + */ + final boolean tryToCompletePhase(final byte executionOrder) { + return executionOrder() >= executionOrder || doTryToCompletePhase(executionOrder); + } + + abstract boolean doTryToCompletePhase(byte targetOrder); + + // + // + // Flags-based mechanics. These include public interfaces as well as all the crud we have lurking in our alignment + // shadow. + // + // + + @Override + public final boolean isSupportedToBuildEffective() { + return isSupportedToBuildEffective; + } + + @Override + public final void setIsSupportedToBuildEffective(final boolean isSupportedToBuildEffective) { + this.isSupportedToBuildEffective = isSupportedToBuildEffective; + } + + @Override + public final boolean isSupportedByFeatures() { + final int fl = flags & SET_SUPPORTED_BY_FEATURES; + if (fl != 0) { + return fl == SET_SUPPORTED_BY_FEATURES; + } + if (isIgnoringIfFeatures()) { + flags |= SET_SUPPORTED_BY_FEATURES; + return true; + } + + /* + * If parent is supported, we need to check if-features statements of this context. + */ + if (isParentSupportedByFeatures()) { + // If the set of supported features has not been provided, all features are supported by default. + final Set supportedFeatures = getFromNamespace(SupportedFeaturesNamespace.class, + SupportedFeatures.SUPPORTED_FEATURES); + if (supportedFeatures == null || StmtContextUtils.checkFeatureSupport(this, supportedFeatures)) { + flags |= SET_SUPPORTED_BY_FEATURES; + return true; + } + } + + // Either parent is not supported or this statement is not supported + flags |= HAVE_SUPPORTED_BY_FEATURES; + return false; + } + + protected abstract boolean isParentSupportedByFeatures(); + + /** + * Config statements are not all that common which means we are performing a recursive search towards the root + * every time {@link #effectiveConfig()} is invoked. This is quite expensive because it causes a linear search + * for the (usually non-existent) config statement. + * + *

+ * This method maintains a resolution cache, so once we have returned a result, we will keep on returning the same + * result without performing any lookups, solely to support {@link #effectiveConfig()}. + * + *

+ * Note: use of this method implies that {@link #isIgnoringConfig()} is realized with + * {@link #isIgnoringConfig(StatementContextBase)}. + */ + final @NonNull EffectiveConfig effectiveConfig(final ReactorStmtCtx parent) { + return (flags & HAVE_CONFIG) != 0 ? EFFECTIVE_CONFIGS[flags & MASK_CONFIG] : loadEffectiveConfig(parent); + } + + private @NonNull EffectiveConfig loadEffectiveConfig(final ReactorStmtCtx parent) { + final EffectiveConfig parentConfig = parent.effectiveConfig(); + + final EffectiveConfig myConfig; + if (parentConfig != EffectiveConfig.IGNORED && !definition().support().isIgnoringConfig()) { + final Optional optConfig = findSubstatementArgument(ConfigEffectiveStatement.class); + if (optConfig.isPresent()) { + if (optConfig.orElseThrow()) { + // Validity check: if parent is config=false this cannot be a config=true + InferenceException.throwIf(parentConfig == EffectiveConfig.FALSE, this, + "Parent node has config=false, this node must not be specifed as config=true"); + myConfig = EffectiveConfig.TRUE; + } else { + myConfig = EffectiveConfig.FALSE; + } + } else { + // If "config" statement is not specified, the default is the same as the parent's "config" value. + myConfig = parentConfig; + } + } else { + myConfig = EffectiveConfig.IGNORED; + } + + flags = (byte) (flags & ~MASK_CONFIG | HAVE_CONFIG | myConfig.ordinal()); + return myConfig; + } + + protected abstract boolean isIgnoringConfig(); + + /** + * This method maintains a resolution cache for ignore config, so once we have returned a result, we will + * keep on returning the same result without performing any lookups. Exists only to support + * {@link SubstatementContext#isIgnoringConfig()}. + * + *

+ * Note: use of this method implies that {@link #isConfiguration()} is realized with + * {@link #effectiveConfig(StatementContextBase)}. + */ + final boolean isIgnoringConfig(final StatementContextBase parent) { + return EffectiveConfig.IGNORED == effectiveConfig(parent); + } + + protected abstract boolean isIgnoringIfFeatures(); + + /** + * This method maintains a resolution cache for ignore if-feature, so once we have returned a result, we will + * keep on returning the same result without performing any lookups. Exists only to support + * {@link SubstatementContext#isIgnoringIfFeatures()}. + */ + final boolean isIgnoringIfFeatures(final StatementContextBase parent) { + final int fl = flags & SET_IGNORE_IF_FEATURE; + if (fl != 0) { + return fl == SET_IGNORE_IF_FEATURE; + } + if (definition().support().isIgnoringIfFeatures() || parent.isIgnoringIfFeatures()) { + flags |= SET_IGNORE_IF_FEATURE; + return true; + } + + flags |= HAVE_IGNORE_IF_FEATURE; + return false; + } + + // These two exist only due to memory optimization, should live in AbstractResumedStatement. + final boolean fullyDefined() { + return boolFlag; + } + + final void setFullyDefined() { + boolFlag = true; + } + + // This exists only due to memory optimization, should live in ReplicaStatementContext. In this context the flag + // indicates the need to drop source's reference count when we are being swept. + final boolean haveSourceReference() { + return boolFlag; + } + + // These three exist due to memory optimization, should live in InferredStatementContext. In this context the flag + // indicates whether or not this statement's substatement file was modified, i.e. it is not quite the same as the + // prototype's file. + final boolean isModified() { + return boolFlag; + } + + final void setModified() { + boolFlag = true; + } + + final void setUnmodified() { + boolFlag = false; + } + + // These two exist only for StatementContextBase. Since we are squeezed for size, with only a single bit available + // in flags, we default to 'false' and only set the flag to true when we are absolutely sure -- and all other cases + // err on the side of caution by taking the time to evaluate each substatement separately. + final boolean allSubstatementsContextIndependent() { + return (flags & ALL_INDEPENDENT) != 0; + } + + final void setAllSubstatementsContextIndependent() { + flags |= ALL_INDEPENDENT; + } + + // + // + // Various functionality from AbstractTypeStatementSupport. This used to work on top of SchemaPath, now it still + // lives here. Ultimate future is either proper graduation or (more likely) move to AbstractTypeStatementSupport. + // + // + + @Override + public final QName argumentAsTypeQName() { + return interpretAsQName(getRawArgument()); + } + + @Override + public final QNameModule effectiveNamespace() { + // FIXME: there has to be a better way to do this + return getSchemaPath().getLastComponent().getModule(); + } + + // + // + // Common SchemaPath cache. All of this is bound to be removed once YANGTOOLS-1066 is done. + // + // + + // Exists only to support {SubstatementContext,InferredStatementContext}.schemaPath() + @Deprecated + final @Nullable SchemaPath substatementGetSchemaPath() { + if (schemaPath == null) { + schemaPath = createSchemaPath((StatementContextBase) coerceParentContext()); + } + return schemaPath; + } + + // FIXME: 7.0.0: this method's logic needs to be moved to the respective StatementSupport classes + @Deprecated + private SchemaPath createSchemaPath(final StatementContextBase parent) { + final SchemaPath parentPath = parent.getSchemaPath(); + if (StmtContextUtils.isUnknownStatement(this)) { + return parentPath.createChild(publicDefinition().getStatementName()); + } + final Object argument = argument(); + if (argument instanceof QName) { + final QName qname = (QName) argument; + if (producesDeclared(UsesStatement.class)) { + return parentPath; + } + + return parentPath.createChild(qname); + } + if (argument instanceof String) { + return parentPath.createChild(interpretAsQName((String) argument)); + } + if (argument instanceof SchemaNodeIdentifier + && (producesDeclared(AugmentStatement.class) || producesDeclared(RefineStatement.class) + || producesDeclared(DeviationStatement.class))) { + + return parentPath.createChild(((SchemaNodeIdentifier) argument).getNodeIdentifiers()); + } + + // FIXME: this does not look right, investigate more? + return parentPath; + } + + private @NonNull QName interpretAsQName(final String argument) { + // FIXME: This may yield illegal argument exceptions + return StmtContextUtils.qnameFromArgument(getOriginalCtx().orElse(this), argument); + } + // // // Reference counting mechanics start. Please keep these methods in one block for clarity. Note this does not @@ -243,6 +665,16 @@ abstract class ReactorStmtCtx, E extends Effec // // + /** + * Local knowledge of {@link #refcount} values up to statement root. We use this field to prevent recursive lookups + * in {@link #noParentRefs(StatementContextBase)} -- once we discover a parent reference once, we keep that + * knowledge and update it when {@link #sweep()} is invoked. + */ + private byte parentRef = PARENTREF_UNKNOWN; + private static final byte PARENTREF_UNKNOWN = -1; + private static final byte PARENTREF_ABSENT = 0; + private static final byte PARENTREF_PRESENT = 1; + /** * Acquire a reference on this context. As long as there is at least one reference outstanding, * {@link #buildEffective()} will not result in {@link #effectiveSubstatements()} being discarded. @@ -273,6 +705,7 @@ abstract class ReactorStmtCtx, E extends Effec } if (current <= REFCOUNT_NONE) { // Underflow, become defunct + // FIXME: add a global 'warn once' flag LOG.warn("Statement refcount underflow, reference counting disabled for {}", this, new Throwable()); refcount = REFCOUNT_DEFUNCT; return; @@ -280,28 +713,70 @@ abstract class ReactorStmtCtx, E extends Effec refcount = current - 1; LOG.trace("Refcount {} on {}", refcount, this); - if (isSweepable()) { - // We are no longer guarded by effective instance - sweepOnDecrement(); + + if (refcount == REFCOUNT_NONE) { + lastDecRef(); } } /** - * Sweep this statement context as a result of {@link #sweepSubstatements()}, i.e. when parent is also being swept. + * Return {@code true} if this context has no outstanding references. + * + * @return True if this context has no outstanding references. */ - private void sweep() { - if (isSweepable()) { - LOG.trace("Releasing {}", this); - sweepState(); + final boolean noRefs() { + final int local = refcount; + return local < REFCOUNT_NONE || local == REFCOUNT_NONE && noParentRef(); + } + + private void lastDecRef() { + if (noImplictRef()) { + // We are no longer guarded by effective instance + sweepOnDecrement(); + return; + } + + final byte prevRefs = parentRef; + if (prevRefs == PARENTREF_ABSENT) { + // We are the last reference towards root, any children who observed PARENTREF_PRESENT from us need to be + // updated + markNoParentRef(); + } else if (prevRefs == PARENTREF_UNKNOWN) { + // Noone observed our parentRef, just update it + loadParentRefcount(); } } + static final void markNoParentRef(final Collection> substatements) { + for (ReactorStmtCtx stmt : substatements) { + final byte prevRef = stmt.parentRef; + stmt.parentRef = PARENTREF_ABSENT; + if (prevRef == PARENTREF_PRESENT && stmt.refcount == REFCOUNT_NONE) { + // Child thinks it is pinned down, update its perspective + stmt.markNoParentRef(); + } + } + } + + abstract void markNoParentRef(); + static final void sweep(final Collection> substatements) { for (ReactorStmtCtx stmt : substatements) { stmt.sweep(); } } + /** + * Sweep this statement context as a result of {@link #sweepSubstatements()}, i.e. when parent is also being swept. + */ + private void sweep() { + parentRef = PARENTREF_ABSENT; + if (refcount == REFCOUNT_NONE && noImplictRef()) { + LOG.trace("Releasing {}", this); + sweepState(); + } + } + static final int countUnswept(final Collection> substatements) { int result = 0; for (ReactorStmtCtx stmt : substatements) { @@ -327,7 +802,7 @@ abstract class ReactorStmtCtx, E extends Effec // Called when this statement does not have an implicit reference and have reached REFCOUNT_NONE private void sweepOnDecrement() { LOG.trace("Sweeping on decrement {}", this); - if (noParentRefcount()) { + if (noParentRef()) { // No further parent references, sweep our state. sweepState(); } @@ -355,7 +830,7 @@ abstract class ReactorStmtCtx, E extends Effec } // parent is potentially reclaimable - if (noParentRefcount()) { + if (noParentRef()) { LOG.trace("Cleanup {} of parent {}", refcount, this); if (sweepState()) { final ReactorStmtCtx parent = getParentContext(); @@ -370,29 +845,40 @@ abstract class ReactorStmtCtx, E extends Effec return effectiveInstance != null || !isSupportedToBuildEffective(); } - // FIXME: cache the resolution of this - private boolean noParentRefcount() { + private boolean noParentRef() { + return parentRefcount() == PARENTREF_ABSENT; + } + + private byte parentRefcount() { + final byte refs; + return (refs = parentRef) != PARENTREF_UNKNOWN ? refs : loadParentRefcount(); + } + + private byte loadParentRefcount() { + return parentRef = calculateParentRefcount(); + } + + private byte calculateParentRefcount() { final ReactorStmtCtx parent = getParentContext(); - if (parent != null) { - // There are three possibilities: - // - REFCOUNT_NONE, in which case we need to search next parent - // - negative (< REFCOUNT_NONE), meaning parent is in some stage of sweeping, hence it does not have - // a reference to us - // - positive (> REFCOUNT_NONE), meaning parent has an explicit refcount which is holding us down - final int refs = parent.refcount; - return refs == REFCOUNT_NONE ? parent.noParentRefcount() : refs < REFCOUNT_NONE; + if (parent == null) { + return PARENTREF_ABSENT; } - return true; + // There are three possibilities: + // - REFCOUNT_NONE, in which case we need to search next parent + // - negative (< REFCOUNT_NONE), meaning parent is in some stage of sweeping, hence it does not have + // a reference to us + // - positive (> REFCOUNT_NONE), meaning parent has an explicit refcount which is holding us down + final int refs = parent.refcount; + if (refs == REFCOUNT_NONE) { + return parent.parentRefcount(); + } + return refs < REFCOUNT_NONE ? PARENTREF_ABSENT : PARENTREF_PRESENT; } private boolean isAwaitingChildren() { return refcount > REFCOUNT_SWEEPING && refcount < REFCOUNT_NONE; } - private boolean isSweepable() { - return refcount == REFCOUNT_NONE && noImplictRef(); - } - private void sweepOnChildDone() { LOG.trace("Sweeping on child done {}", this); final int current = refcount; @@ -429,6 +915,7 @@ abstract class ReactorStmtCtx, E extends Effec return true; } if (childRefs < 0 || childRefs >= REFCOUNT_DEFUNCT) { + // FIXME: add a global 'warn once' flag LOG.warn("Negative child refcount {} cannot be stored, reference counting disabled for {}", childRefs, this, new Throwable()); refcount = REFCOUNT_DEFUNCT;