Skip to content
Permalink
Browse files
8267191: Avoid repeated SystemDictionaryShared::should_be_excluded calls
Reviewed-by: dholmes, coleenp
  • Loading branch information
iklam committed May 19, 2021
1 parent 74f30ad commit b961f2535c9508d6f8e580b8bf53538d6f72b27c
Showing with 55 additions and 49 deletions.
  1. +52 −47 src/hotspot/share/classfile/systemDictionaryShared.cpp
  2. +3 −2 src/hotspot/share/classfile/systemDictionaryShared.hpp
@@ -80,6 +80,7 @@ bool SystemDictionaryShared::_dump_in_progress = false;
class DumpTimeSharedClassInfo: public CHeapObj<mtClass> {
bool _excluded;
bool _is_early_klass;
bool _has_checked_exclusion;
public:
struct DTLoaderConstraint {
Symbol* _name;
@@ -122,6 +123,7 @@ class DumpTimeSharedClassInfo: public CHeapObj<mtClass> {
_nest_host = NULL;
_failed_verification = false;
_is_archived_lambda_proxy = false;
_has_checked_exclusion = false;
_id = -1;
_clsfile_size = -1;
_clsfile_crc32 = -1;
@@ -174,10 +176,6 @@ class DumpTimeSharedClassInfo: public CHeapObj<mtClass> {
}
}

void set_excluded() {
_excluded = true;
}

bool is_excluded() {
// _klass may become NULL due to DynamicArchiveBuilder::set_to_null
return _excluded || _failed_verification || _klass == NULL;
@@ -188,21 +186,14 @@ class DumpTimeSharedClassInfo: public CHeapObj<mtClass> {
return _is_early_klass;
}

void set_failed_verification() {
_failed_verification = true;
}

bool failed_verification() {
return _failed_verification;
}

void set_nest_host(InstanceKlass* nest_host) {
_nest_host = nest_host;
}

InstanceKlass* nest_host() {
return _nest_host;
}
// simple accessors
void set_excluded() { _excluded = true; }
bool has_checked_exclusion() const { return _has_checked_exclusion; }
void set_has_checked_exclusion() { _has_checked_exclusion = true; }
bool failed_verification() const { return _failed_verification; }
void set_failed_verification() { _failed_verification = true; }
InstanceKlass* nest_host() const { return _nest_host; }
void set_nest_host(InstanceKlass* nest_host) { _nest_host = nest_host; }
};

inline unsigned DumpTimeSharedClassTable_hash(InstanceKlass* const& k) {
@@ -1326,41 +1317,60 @@ bool SystemDictionaryShared::is_early_klass(InstanceKlass* ik) {
return (info != NULL) ? info->is_early_klass() : false;
}

void SystemDictionaryShared::warn_excluded(InstanceKlass* k, const char* reason) {
// Returns true so the caller can do: return warn_excluded(".....");
bool SystemDictionaryShared::warn_excluded(InstanceKlass* k, const char* reason) {
ResourceMark rm;
log_warning(cds)("Skipping %s: %s", k->name()->as_C_string(), reason);
return true;
}

bool SystemDictionaryShared::should_be_excluded(InstanceKlass* k) {
bool SystemDictionaryShared::check_for_exclusion(InstanceKlass* k, DumpTimeSharedClassInfo* info) {
if (MetaspaceShared::is_in_shared_metaspace(k)) {
// We have reached a super type that's already in the base archive. Treat it
// as "not excluded".
assert(DynamicDumpSharedSpaces, "must be");
return false;
}

if (info == NULL) {
info = _dumptime_table->get(k);
assert(info != NULL, "supertypes of any classes in _dumptime_table must either be shared, or must also be in _dumptime_table");
}

if (!info->has_checked_exclusion()) {
if (check_for_exclusion_impl(k)) {
info->set_excluded();
}
info->set_has_checked_exclusion();
}

return info->is_excluded();
}

bool SystemDictionaryShared::check_for_exclusion_impl(InstanceKlass* k) {
if (k->is_in_error_state()) {
warn_excluded(k, "In error state");
return true;
return warn_excluded(k, "In error state");
}
if (k->has_been_redefined()) {
warn_excluded(k, "Has been redefined");
return true;
return warn_excluded(k, "Has been redefined");
}
if (!k->is_hidden() && k->shared_classpath_index() < 0 && is_builtin(k)) {
// These are classes loaded from unsupported locations (such as those loaded by JVMTI native
// agent during dump time).
warn_excluded(k, "Unsupported location");
return true;
return warn_excluded(k, "Unsupported location");
}
if (k->signers() != NULL) {
// We cannot include signed classes in the archive because the certificates
// used during dump time may be different than those used during
// runtime (due to expiration, etc).
warn_excluded(k, "Signed JAR");
return true;
return warn_excluded(k, "Signed JAR");
}
if (is_jfr_event_class(k)) {
// We cannot include JFR event classes because they need runtime-specific
// instrumentation in order to work with -XX:FlightRecorderOptions:retransform=false.
// There are only a small number of these classes, so it's not worthwhile to
// support them and make CDS more complicated.
warn_excluded(k, "JFR event class");
return true;
return warn_excluded(k, "JFR event class");
}
if (k->init_state() < InstanceKlass::linked) {
// In CDS dumping, we will attempt to link all classes. Those that fail to link will
@@ -1374,12 +1384,10 @@ bool SystemDictionaryShared::should_be_excluded(InstanceKlass* k) {
// a custom ClassLoader.loadClass() may be called, at a point where the
// class loader doesn't expect it.
if (has_class_failed_verification(k)) {
warn_excluded(k, "Failed verification");
return true;
return warn_excluded(k, "Failed verification");
} else {
if (!k->has_old_class_version()) {
warn_excluded(k, "Not linked");
return true;
return warn_excluded(k, "Not linked");
}
}
}
@@ -1393,34 +1401,33 @@ bool SystemDictionaryShared::should_be_excluded(InstanceKlass* k) {
}

if (k->has_old_class_version() && k->is_linked()) {
warn_excluded(k, "Old class has been linked");
return true;
return warn_excluded(k, "Old class has been linked");
}

InstanceKlass* super = k->java_super();
if (super != NULL && should_be_excluded(super)) {
if (k->is_hidden() && !is_registered_lambda_proxy_class(k)) {
ResourceMark rm;
log_warning(cds)("Skipping %s: super class %s is excluded", k->name()->as_C_string(), super->name()->as_C_string());
log_debug(cds)("Skipping %s: Hidden class", k->name()->as_C_string());
return true;
}

if (k->is_hidden() && !is_registered_lambda_proxy_class(k)) {
InstanceKlass* super = k->java_super();
if (super != NULL && check_for_exclusion(super, NULL)) {
ResourceMark rm;
log_debug(cds)("Skipping %s: %s", k->name()->as_C_string(), "Hidden class");
log_warning(cds)("Skipping %s: super class %s is excluded", k->name()->as_C_string(), super->name()->as_C_string());
return true;
}

Array<InstanceKlass*>* interfaces = k->local_interfaces();
int len = interfaces->length();
for (int i = 0; i < len; i++) {
InstanceKlass* intf = interfaces->at(i);
if (should_be_excluded(intf)) {
if (check_for_exclusion(intf, NULL)) {
log_warning(cds)("Skipping %s: interface %s is excluded", k->name()->as_C_string(), intf->name()->as_C_string());
return true;
}
}

return false;
return false; // false == k should NOT be excluded
}

// k is a class before relocating by ArchiveBuilder
@@ -1447,9 +1454,7 @@ void SystemDictionaryShared::validate_before_archiving(InstanceKlass* k) {
class ExcludeDumpTimeSharedClasses : StackObj {
public:
bool do_entry(InstanceKlass* k, DumpTimeSharedClassInfo& info) {
if (SystemDictionaryShared::should_be_excluded(k) || info.is_excluded()) {
info.set_excluded();
}
SystemDictionaryShared::check_for_exclusion(k, &info);
return true; // keep on iterating
}
};
@@ -212,8 +212,8 @@ class SystemDictionaryShared: public SystemDictionary {
static void write_lambda_proxy_class_dictionary(LambdaProxyClassDictionary* dictionary);
static bool is_jfr_event_class(InstanceKlass *k);
static bool is_registered_lambda_proxy_class(InstanceKlass* ik);
static void warn_excluded(InstanceKlass* k, const char* reason);
static bool should_be_excluded(InstanceKlass* k);
static bool warn_excluded(InstanceKlass* k, const char* reason);
static bool check_for_exclusion_impl(InstanceKlass* k);

static bool _dump_in_progress;
DEBUG_ONLY(static bool _no_class_loading_should_happen;)
@@ -304,6 +304,7 @@ class SystemDictionaryShared: public SystemDictionary {
return (k->shared_classpath_index() != UNREGISTERED_INDEX);
}
static void check_excluded_classes();
static bool check_for_exclusion(InstanceKlass* k, DumpTimeSharedClassInfo* info);
static void validate_before_archiving(InstanceKlass* k);
static bool is_excluded_class(InstanceKlass* k);
static void set_excluded(InstanceKlass* k);

0 comments on commit b961f25

Please sign in to comment.