jdk-sandbox: comparison hotspot/src/share/vm/code/nmethod.cpp

equal deleted inserted replaced

-:9059987242ca
+:99db666dbe8e
 // attempt to report the event in the unlikely scenario where the
 // event is enabled at the time the nmethod is made a zombie.
 set_unload_reported();
 }
-void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) {
+void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive, bool mark_on_stack) {
 if (ic->is_icholder_call()) {
 // The only exception is compiledICHolder oops which may
 // yet be marked below. (We check this further below).
 CompiledICHolder* cichk_oop = ic->cached_icholder();
+if (mark_on_stack) {
+Metadata::mark_on_stack(cichk_oop->holder_method());
+Metadata::mark_on_stack(cichk_oop->holder_klass());
+}
 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
 return;
 }
 } else {
 Metadata* ic_oop = ic->cached_metadata();
 if (ic_oop != NULL) {
+if (mark_on_stack) {
+Metadata::mark_on_stack(ic_oop);
+}
 if (ic_oop->is_klass()) {
 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
 return;
 }
 } else if (ic_oop->is_method()) {
 if (unloading_occurred) {
 RelocIterator iter(this, low_boundary);
 while(iter.next()) {
 if (iter.type() == relocInfo::virtual_call_type) {
 CompiledIC *ic = CompiledIC_at(&iter);
-clean_ic_if_metadata_is_dead(ic, is_alive);
+clean_ic_if_metadata_is_dead(ic, is_alive, false);
 }
 }
 }
 // Compiled code
 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, nmethod* from) {
 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
 }
+bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive, bool unloading_occurred) {
+assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type");
+oop_Relocation* r = iter_at_oop->oop_reloc();
+// Traverse those oops directly embedded in the code.
+// Other oops (oop_index>0) are seen as part of scopes_oops.
+assert(1 == (r->oop_is_immediate()) +
+(r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
+"oop must be found in exactly one place");
+if (r->oop_is_immediate() && r->oop_value() != NULL) {
+// Unload this nmethod if the oop is dead.
+if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
+return true;;
+}
+}
+return false;
+}
+void nmethod::mark_metadata_on_stack_at(RelocIterator* iter_at_metadata) {
+assert(iter_at_metadata->type() == relocInfo::metadata_type, "Wrong relocation type");
+metadata_Relocation* r = iter_at_metadata->metadata_reloc();
+// In this metadata, we must only follow those metadatas directly embedded in
+// the code.  Other metadatas (oop_index>0) are seen as part of
+// the metadata section below.
+assert(1 == (r->metadata_is_immediate()) +
+(r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
+"metadata must be found in exactly one place");
+if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
+Metadata* md = r->metadata_value();
+if (md != _method) Metadata::mark_on_stack(md);
+}
+}
+void nmethod::mark_metadata_on_stack_non_relocs() {
+// Visit the metadata section
+for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
+if (*p == Universe::non_oop_word() || *p == NULL)  continue;  // skip non-oops
+Metadata* md = *p;
+Metadata::mark_on_stack(md);
+}
+// Visit metadata not embedded in the other places.
+if (_method != NULL) Metadata::mark_on_stack(_method);
+}
 bool nmethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
 ResourceMark rm;
 // Make sure the oop's ready to receive visitors
 assert(!is_zombie() && !is_unloaded(),
 // call to post_compiled_method_unload() so that the unloading
 // of this nmethod is reported.
 unloading_occurred = true;
 }
+// When class redefinition is used all metadata in the CodeCache has to be recorded,
+// so that unused "previous versions" can be purged. Since walking the CodeCache can
+// be expensive, the "mark on stack" is piggy-backed on this parallel unloading code.
+bool mark_metadata_on_stack = a_class_was_redefined;
 // Exception cache
 clean_exception_cache(is_alive);
 bool is_unloaded = false;
 bool postponed = false;
 case relocInfo::virtual_call_type:
 if (unloading_occurred) {
 // If class unloading occurred we first iterate over all inline caches and
 // clear ICs where the cached oop is referring to an unloaded klass or method.
-clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive);
+clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive, mark_metadata_on_stack);
 }
 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
 break;
 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
 break;
 case relocInfo::oop_type:
 if (!is_unloaded) {
-// Unload check
+is_unloaded = unload_if_dead_at(&iter, is_alive, unloading_occurred);
-oop_Relocation* r = iter.oop_reloc();
-// Traverse those oops directly embedded in the code.
-// Other oops (oop_index>0) are seen as part of scopes_oops.
-assert(1 == (r->oop_is_immediate()) +
-(r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
-"oop must be found in exactly one place");
-if (r->oop_is_immediate() && r->oop_value() != NULL) {
-if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
-is_unloaded = true;
-}
-}
 }
 break;
-}
+case relocInfo::metadata_type:
+if (mark_metadata_on_stack) {
+mark_metadata_on_stack_at(&iter);
+}
+}
+}
+if (mark_metadata_on_stack) {
+mark_metadata_on_stack_non_relocs();
 }
 if (is_unloaded) {
 return postponed;
 }
 // Visit all immediate references that are embedded in the instruction stream.
 RelocIterator iter(this, low_boundary);
 while (iter.next()) {
 if (iter.type() == relocInfo::metadata_type ) {
 metadata_Relocation* r = iter.metadata_reloc();
-// In this lmetadata, we must only follow those metadatas directly embedded in
+// In this metadata, we must only follow those metadatas directly embedded in
 // the code.  Other metadatas (oop_index>0) are seen as part of
 // the metadata section below.
 assert(1 == (r->metadata_is_immediate()) +
 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
 "metadata must be found in exactly one place");
 if (*p == Universe::non_oop_word() || *p == NULL)  continue;  // skip non-oops
 Metadata* md = *p;
 f(md);
 }
-// Call function Method*, not embedded in these other places.
+// Visit metadata not embedded in the other places.
 if (_method != NULL) f(_method);
 }
 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
 // make sure the oops ready to receive visitors

changeset 27247	99db666dbe8e
parent 26912	19021f626ad2
child 27429	4ccd0992d680