8154239: -Xbootclasspath/a breaks exploded build

Correct exploded modules build system class path search for the boot loader

Reviewed-by: acorn, ccheung, hseigel, jiangli
This commit is contained in:
Lois Foltan 2016-07-26 10:29:27 -04:00
parent 2313844e20
commit 64f4953141
11 changed files with 338 additions and 312 deletions

View file

@ -141,11 +141,11 @@ PerfCounter* ClassLoader::_isUnsyncloadClass = NULL;
PerfCounter* ClassLoader::_load_instance_class_failCounter = NULL;
GrowableArray<ModuleClassPathList*>* ClassLoader::_xpatch_entries = NULL;
ClassPathEntry* ClassLoader::_first_entry = NULL;
ClassPathEntry* ClassLoader::_last_entry = NULL;
int ClassLoader::_num_entries = 0;
GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = NULL;
ClassPathEntry* ClassLoader::_jrt_entry = NULL;
ClassPathEntry* ClassLoader::_first_append_entry = NULL;
bool ClassLoader::_has_jimage = false;
ClassPathEntry* ClassLoader::_last_append_entry = NULL;
int ClassLoader::_num_entries = 0;
#if INCLUDE_CDS
GrowableArray<char*>* ClassLoader::_boot_modules_array = NULL;
GrowableArray<char*>* ClassLoader::_platform_modules_array = NULL;
@ -508,7 +508,7 @@ ClassFileStream* ClassPathImageEntry::open_stream(const char* name, TRAPS) {
#endif
} else {
PackageEntry* package_entry = get_package_entry(name, ClassLoaderData::the_null_class_loader_data(), THREAD);
PackageEntry* package_entry = get_package_entry(name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
if (package_entry != NULL) {
ResourceMark rm;
// Get the module name
@ -651,7 +651,6 @@ void ClassLoader::check_shared_classpath(const char *path) {
#endif
void ClassLoader::setup_bootstrap_search_path() {
assert(_first_entry == NULL, "should not setup bootstrap class search path twice");
const char* sys_class_path = Arguments::get_sysclasspath();
const char* java_class_path = Arguments::get_appclasspath();
if (PrintSharedArchiveAndExit) {
@ -694,7 +693,10 @@ void ClassLoader::setup_xpatch_entries() {
GrowableArray<ModuleXPatchPath*>* xpatch_args = Arguments::get_xpatchprefix();
int num_of_entries = xpatch_args->length();
// Set up the boot loader's xpatch_entries list
assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with -Xpatch");
assert(!UseSharedSpaces, "UseSharedSpaces not supported with -Xpatch");
// Set up the boot loader's _xpatch_entries list
_xpatch_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, true);
for (int i = 0; i < num_of_entries; i++) {
@ -742,10 +744,9 @@ void ClassLoader::setup_xpatch_entries() {
}
void ClassLoader::setup_search_path(const char *class_path, bool bootstrap_search) {
int offset = 0;
int len = (int)strlen(class_path);
int end = 0;
bool mark_append_entry = false;
bool set_base_piece = bootstrap_search;
// Iterate over class path entries
for (int start = 0; start < len; start = end) {
@ -754,21 +755,45 @@ void ClassLoader::setup_search_path(const char *class_path, bool bootstrap_searc
}
EXCEPTION_MARK;
ResourceMark rm(THREAD);
mark_append_entry = (mark_append_entry ||
(bootstrap_search && (start == Arguments::bootclassloader_append_index())));
char* path = NEW_RESOURCE_ARRAY(char, end - start + 1);
strncpy(path, &class_path[start], end - start);
path[end - start] = '\0';
update_class_path_entry_list(path, false, mark_append_entry, false, bootstrap_search);
// Check on the state of the boot loader's append path
if (mark_append_entry && (_first_append_entry == NULL)) {
// Failure to mark the first append entry, most likely
// due to a non-existent path. Record the next entry
// as the first boot loader append entry.
mark_append_entry = true;
// The first time through the bootstrap_search setup, it must be determined
// what the base or core piece of the boot loader search is. Either a java runtime
// image is present or this is an exploded module build situation.
if (set_base_piece) {
assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, "java.base"),
"Incorrect boot loader search path, no java runtime image or java.base exploded build");
struct stat st;
if (os::stat(path, &st) == 0) {
// Directory found
Thread* THREAD = Thread::current();
ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
// Check for a jimage
if (Arguments::has_jimage()) {
assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
assert(new_entry != NULL && new_entry->is_jrt(), "No java runtime image present");
_jrt_entry = new_entry;
++_num_entries;
#if INCLUDE_CDS
if (DumpSharedSpaces) {
JImageFile *jimage = _jrt_entry->jimage();
assert(jimage != NULL, "No java runtime image file present");
ClassLoader::initialize_module_loader_map(jimage);
}
#endif
}
} else {
// If path does not exist, exit
vm_exit_during_initialization("Unable to establish the boot loader search path", path);
}
set_base_piece = false;
} else {
mark_append_entry = false;
// Every entry on the system boot class path after the initial base piece,
// which is set by os::set_boot_path(), is considered an appended entry.
update_class_path_entry_list(path, false, bootstrap_search);
}
#if INCLUDE_CDS
@ -782,6 +807,45 @@ void ClassLoader::setup_search_path(const char *class_path, bool bootstrap_searc
}
}
// During an exploded modules build, each module defined to the boot loader
// will be added to the ClassLoader::_exploded_entries array.
void ClassLoader::add_to_exploded_build_list(Symbol* module_sym, TRAPS) {
assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
// Set up the boot loader's _exploded_entries list
if (_exploded_entries == NULL) {
_exploded_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, true);
}
// Find the module's symbol
ResourceMark rm(THREAD);
const char *module_name = module_sym->as_C_string();
const char *home = Arguments::get_java_home();
const char file_sep = os::file_separator()[0];
// 10 represents the length of "modules" + 2 file separators + \0
size_t len = strlen(home) + strlen(module_name) + 10;
char *path = NEW_C_HEAP_ARRAY(char, len, mtModule);
jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
struct stat st;
if (os::stat(path, &st) == 0) {
// Directory found
ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
// If the path specification is valid, enter it into this module's list.
// There is no need to check for duplicate modules in the exploded entry list,
// since no two modules with the same name can be defined to the boot loader.
// This is checked at module definition time in Modules::define_module.
if (new_entry != NULL) {
ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
module_cpl->add_to_list(new_entry);
_exploded_entries->push(module_cpl);
log_info(class, load)("path: %s", path);
}
}
FREE_C_HEAP_ARRAY(char, path);
}
ClassPathEntry* ClassLoader::create_class_path_entry(const char *path, const struct stat* st,
bool throw_exception,
bool is_boot_append, TRAPS) {
@ -872,21 +936,9 @@ ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bo
return NULL;
}
// The boot class loader must adhere to specfic visibility rules.
// Prior to loading a class in a named package, the package is checked
// to see if it is in a module defined to the boot loader. If the
// package is not in a module defined to the boot loader, the class
// must be loaded only in the boot loader's append path, which
// consists of [-Xbootclasspath/a]; [jvmti appended entries]
void ClassLoader::set_first_append_entry(ClassPathEntry *new_entry) {
if (_first_append_entry == NULL) {
_first_append_entry = new_entry;
}
}
// returns true if entry already on class path
bool ClassLoader::contains_entry(ClassPathEntry *entry) {
ClassPathEntry* e = _first_entry;
ClassPathEntry* e = _first_append_entry;
while (e != NULL) {
// assume zip entries have been canonicalized
if (strcmp(entry->name(), e->name()) == 0) {
@ -899,41 +951,24 @@ bool ClassLoader::contains_entry(ClassPathEntry *entry) {
void ClassLoader::add_to_list(ClassPathEntry *new_entry) {
if (new_entry != NULL) {
if (_last_entry == NULL) {
_first_entry = _last_entry = new_entry;
if (_last_append_entry == NULL) {
assert(_first_append_entry == NULL, "boot loader's append class path entry list not empty");
_first_append_entry = _last_append_entry = new_entry;
} else {
_last_entry->set_next(new_entry);
_last_entry = new_entry;
_last_append_entry->set_next(new_entry);
_last_append_entry = new_entry;
}
}
_num_entries ++;
}
void ClassLoader::prepend_to_list(ClassPathEntry *new_entry) {
if (new_entry != NULL) {
if (_last_entry == NULL) {
_first_entry = _last_entry = new_entry;
} else {
new_entry->set_next(_first_entry);
_first_entry = new_entry;
}
}
_num_entries ++;
_num_entries++;
}
void ClassLoader::add_to_list(const char *apath) {
update_class_path_entry_list((char*)apath, false, false, false, false);
}
void ClassLoader::prepend_to_list(const char *apath) {
update_class_path_entry_list((char*)apath, false, false, true, false);
update_class_path_entry_list((char*)apath, false, false);
}
// Returns true IFF the file/dir exists and the entry was successfully created.
bool ClassLoader::update_class_path_entry_list(const char *path,
bool check_for_duplicates,
bool mark_append_entry,
bool prepend_entry,
bool is_boot_append,
bool throw_exception) {
struct stat st;
@ -946,19 +981,10 @@ bool ClassLoader::update_class_path_entry_list(const char *path,
return false;
}
// Ensure that the first boot loader append entry will always be set correctly.
assert((!mark_append_entry ||
(mark_append_entry && (!check_for_duplicates || !contains_entry(new_entry)))),
"failed to mark boot loader's first append boundary");
// Do not reorder the bootclasspath which would break get_system_package().
// Add new entry to linked list
if (!check_for_duplicates || !contains_entry(new_entry)) {
ClassLoaderExt::add_class_path_entry(path, check_for_duplicates, new_entry, prepend_entry);
if (mark_append_entry) {
set_first_append_entry(new_entry);
}
ClassLoaderExt::add_class_path_entry(path, check_for_duplicates, new_entry);
}
return true;
} else {
@ -971,30 +997,47 @@ bool ClassLoader::update_class_path_entry_list(const char *path,
}
}
static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
ResourceMark rm;
int num_of_entries = module_list->length();
for (int i = 0; i < num_of_entries; i++) {
ClassPathEntry* e;
ModuleClassPathList* mpl = module_list->at(i);
tty->print("%s=", mpl->module_name()->as_C_string());
e = mpl->module_first_entry();
while (e != NULL) {
tty->print("%s", e->name());
e = e->next();
if (e != NULL) {
tty->print("%s", os::path_separator());
}
}
tty->print(" ;");
}
}
void ClassLoader::print_bootclasspath() {
ClassPathEntry* e;
tty->print("[bootclasspath= ");
// Print -Xpatch module/path specifications first
if (_xpatch_entries != NULL) {
ResourceMark rm;
int num_of_entries = _xpatch_entries->length();
for (int i = 0; i < num_of_entries; i++) {
ModuleClassPathList* mpl = _xpatch_entries->at(i);
tty->print("%s=", mpl->module_name()->as_C_string());
e = mpl->module_first_entry();
while (e != NULL) {
tty->print("%s", e->name());
e = e->next();
if (e != NULL) {
tty->print("%s", os::path_separator());
}
}
tty->print(" ;");
print_module_entry_table(_xpatch_entries);
}
// [jimage | exploded modules build]
if (has_jrt_entry()) {
// Print the location of the java runtime image
tty->print("%s ;", _jrt_entry->name());
} else {
// Print exploded module build path specifications
if (_exploded_entries != NULL) {
print_module_entry_table(_exploded_entries);
}
}
e = _first_entry;
// appended entries
e = _first_append_entry;
while (e != NULL) {
tty->print("%s ;", e->name());
e = e->next();
@ -1298,6 +1341,60 @@ const char* ClassLoader::file_name_for_class_name(const char* class_name,
return file_name;
}
// Search either the xpatch or exploded build entries for class
ClassFileStream* ClassLoader::search_module_entries(const GrowableArray<ModuleClassPathList*>* const module_list,
const char* const class_name, const char* const file_name, TRAPS) {
ClassFileStream* stream = NULL;
// Find the class' defining module in the boot loader's module entry table
PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
// If the module system has not defined java.base yet, then
// classes loaded are assumed to be defined to java.base.
// When java.base is eventually defined by the module system,
// all packages of classes that have been previously loaded
// are verified in ModuleEntryTable::verify_javabase_packages().
if (!Universe::is_module_initialized() &&
!ModuleEntryTable::javabase_defined() &&
mod_entry == NULL) {
mod_entry = ModuleEntryTable::javabase_module();
}
// The module must be a named module
if (mod_entry != NULL && mod_entry->is_named()) {
int num_of_entries = module_list->length();
const Symbol* class_module_name = mod_entry->name();
// Loop through all the modules in either the xpatch or exploded entries looking for module
for (int i = 0; i < num_of_entries; i++) {
ModuleClassPathList* module_cpl = module_list->at(i);
Symbol* module_cpl_name = module_cpl->module_name();
if (module_cpl_name->fast_compare(class_module_name) == 0) {
// Class' module has been located, attempt to load
// the class from the module's ClassPathEntry list.
ClassPathEntry* e = module_cpl->module_first_entry();
while (e != NULL) {
stream = e->open_stream(file_name, CHECK_NULL);
// No context.check is required since CDS is not supported
// for an exploded modules build or if -Xpatch is specified.
if (NULL != stream) {
return stream;
}
e = e->next();
}
// If the module was located, break out even if the class was not
// located successfully from that module's ClassPathEntry list.
// There will not be another valid entry for that module.
return NULL;
}
}
}
return NULL;
}
instanceKlassHandle ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
assert(name != NULL, "invariant");
assert(THREAD->is_Java_thread(), "must be a JavaThread");
@ -1321,18 +1418,19 @@ instanceKlassHandle ClassLoader::load_class(Symbol* name, bool search_append_onl
s2 classpath_index = 0;
ClassPathEntry* e = NULL;
// If DumpSharedSpaces is true, boot loader visibility boundaries are set
// to be _first_entry to the end (all path entries). No -Xpatch entries are
// included since CDS and AppCDS are not supported if -Xpatch is specified.
// If DumpSharedSpaces is true boot loader visibility boundaries are set to:
// - [jimage] + [_first_append_entry to _last_append_entry] (all path entries).
// No -Xpatch entries or exploded module builds are included since CDS
// is not supported if -Xpatch or exploded module builds are used.
//
// If search_append_only is true, boot loader visibility boundaries are
// set to be _first_append_entry to the end. This includes:
// [-Xbootclasspath/a]; [jvmti appended entries]
//
// If both DumpSharedSpaces and search_append_only are false, boot loader
// visibility boundaries are set to be _first_entry to the entry before
// the _first_append_entry. This would include:
// [-Xpatch:<module>=<file>(<pathsep><file>)*]; [exploded build | jimage]
// visibility boundaries are set to be the -Xpatch entries plus the base piece.
// This would include:
// [-Xpatch:<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
//
// DumpSharedSpaces and search_append_only are mutually exclusive and cannot
// be true at the same time.
@ -1341,85 +1439,37 @@ instanceKlassHandle ClassLoader::load_class(Symbol* name, bool search_append_onl
// Load Attempt #1: -Xpatch
// Determine the class' defining module. If it appears in the _xpatch_entries,
// attempt to load the class from those locations specific to the module.
// Specifications to -Xpatch can contain a partial number of classes
// that are part of the overall module definition. So if a particular class is not
// found within its module specification, the search should continue to Load Attempt #2.
// Note: The -Xpatch entries are never searched if the boot loader's
// visibility boundary is limited to only searching the append entries.
if (_xpatch_entries != NULL && !search_append_only && !DumpSharedSpaces) {
// Find the module in the boot loader's module entry table
PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), THREAD);
ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
// If the module system has not defined java.base yet, then
// classes loaded are assumed to be defined to java.base.
// When java.base is eventually defined by the module system,
// all packages of classes that have been previously loaded
// are verified in ModuleEntryTable::verify_javabase_packages().
if (!Universe::is_module_initialized() &&
!ModuleEntryTable::javabase_defined() &&
mod_entry == NULL) {
mod_entry = ModuleEntryTable::javabase_module();
}
// The module must be a named module
if (mod_entry != NULL && mod_entry->is_named()) {
int num_of_entries = _xpatch_entries->length();
const Symbol* class_module_name = mod_entry->name();
// Loop through all the xpatch entries looking for module
for (int i = 0; i < num_of_entries; i++) {
ModuleClassPathList* module_cpl = _xpatch_entries->at(i);
Symbol* module_cpl_name = module_cpl->module_name();
if (module_cpl_name->fast_compare(class_module_name) == 0) {
// Class' module has been located, attempt to load
// the class from the module's ClassPathEntry list.
e = module_cpl->module_first_entry();
while (e != NULL) {
stream = e->open_stream(file_name, CHECK_NULL);
// No context.check is required since both CDS
// and AppCDS are turned off if -Xpatch is specified.
if (NULL != stream) {
break;
}
e = e->next();
}
// If the module was located in the xpatch entries, break out
// even if the class was not located successfully from that module's
// ClassPathEntry list. There will not be another valid entry for
// that module in the _xpatch_entries array.
break;
}
}
}
stream = search_module_entries(_xpatch_entries, class_name, file_name, CHECK_NULL);
}
// Load Attempt #2: [exploded build | jimage]
// Load Attempt #2: [jimage | exploded build]
if (!search_append_only && (NULL == stream)) {
e = _first_entry;
while ((e != NULL) && (e != _first_append_entry)) {
stream = e->open_stream(file_name, CHECK_NULL);
if (has_jrt_entry()) {
e = _jrt_entry;
stream = _jrt_entry->open_stream(file_name, CHECK_NULL);
if (!context.check(stream, classpath_index)) {
return NULL;
}
if (NULL != stream) {
break;
}
e = e->next();
++classpath_index;
} else {
// Exploded build - attempt to locate class in its defining module's location.
assert(_exploded_entries != NULL, "No exploded build entries present");
stream = search_module_entries(_exploded_entries, class_name, file_name, CHECK_NULL);
}
}
// Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
if ((search_append_only || DumpSharedSpaces) && (NULL == stream)) {
// For the boot loader append path search, must calculate
// the starting classpath_index prior to attempting to
// load the classfile.
if (search_append_only) {
ClassPathEntry *tmp_e = _first_entry;
while ((tmp_e != NULL) && (tmp_e != _first_append_entry)) {
tmp_e = tmp_e->next();
++classpath_index;
}
}
// For the boot loader append path search, the starting classpath_index
// for the appended piece is always 1 to account for either the
// _jrt_entry or the _exploded_entries.
assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
classpath_index = 1;
e = _first_append_entry;
while (e != NULL) {
@ -1597,16 +1647,25 @@ void classLoader_init1() {
}
// Complete the ClassPathEntry setup for the boot loader
void classLoader_init2() {
void ClassLoader::classLoader_init2(TRAPS) {
// Create the moduleEntry for java.base
create_javabase();
// Setup the list of module/path pairs for -Xpatch processing
// This must be done after the SymbolTable is created in order
// to use fast_compare on module names instead of a string compare.
if (Arguments::get_xpatchprefix() != NULL) {
ClassLoader::setup_xpatch_entries();
setup_xpatch_entries();
}
// Determine if this is an exploded build
ClassLoader::set_has_jimage();
// Setup the initial java.base/path pair for the exploded build entries.
// As more modules are defined during module system initialization, more
// entries will be added to the exploded build array.
if (!has_jrt_entry()) {
assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with exploded module builds");
assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
add_to_exploded_build_list(vmSymbols::java_base(), CHECK);
}
}
@ -1654,26 +1713,6 @@ void ClassLoader::create_javabase() {
}
}
void ClassLoader::set_has_jimage() {
// Determine if this is an exploded build. When looking for
// the jimage file, only search the piece of the boot
// loader's boot class path which contains [exploded build | jimage].
// Do not search the boot loader's xpatch entries or append path.
ClassPathEntry* e = _first_entry;
ClassPathEntry* last_e = _first_append_entry;
while ((e != NULL) && (e != last_e)) {
JImageFile *jimage = e->jimage();
if (jimage != NULL && e->is_jrt()) {
_has_jimage = true;
#if INCLUDE_CDS
ClassLoader::initialize_module_loader_map(jimage);
#endif
return;
}
e = e->next();
}
}
#ifndef PRODUCT
// CompileTheWorld
@ -1762,14 +1801,19 @@ void ClassLoader::compile_the_world() {
HandleMark hm(THREAD);
ResourceMark rm(THREAD);
assert(has_jrt_entry(), "Compile The World not supported with exploded module build");
// Find bootstrap loader
Handle system_class_loader (THREAD, SystemDictionary::java_system_loader());
// Iterate over all bootstrap class path entries
ClassPathEntry* e = _first_entry;
jlong start = os::javaTimeMillis();
// Compile the world for the modular java runtime image
_jrt_entry->compile_the_world(system_class_loader, CATCH);
// Iterate over all bootstrap class path appended entries
ClassPathEntry* e = _first_append_entry;
while (e != NULL) {
// We stop at "modules" jimage, unless it is the first bootstrap path entry
if (e->is_jrt() && e != _first_entry) break;
assert(!e->is_jrt(), "A modular java runtime image is present on the list of appended entries");
e->compile_the_world(system_class_loader, CATCH);
e = e->next();
}