openjdk/src/hotspot/share/cds/cdsConfig.cpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#include "cds/archiveHeapLoader.hpp"
#include "cds/cdsConfig.hpp"
#include "cds/classListWriter.hpp"
#include "cds/heapShared.hpp"
#include "classfile/classLoaderDataShared.hpp"
#include "classfile/moduleEntry.hpp"
#include "include/jvm_io.h"
#include "logging/log.hpp"
#include "memory/universe.hpp"
#include "runtime/arguments.hpp"
#include "runtime/java.hpp"
#include "utilities/defaultStream.hpp"

bool CDSConfig::_is_dumping_static_archive = false;
bool CDSConfig::_is_dumping_dynamic_archive = false;
bool CDSConfig::_is_using_optimized_module_handling = true;
bool CDSConfig::_is_dumping_full_module_graph = true;
bool CDSConfig::_is_using_full_module_graph = true;

char* CDSConfig::_default_archive_path = nullptr;
char* CDSConfig::_static_archive_path = nullptr;
char* CDSConfig::_dynamic_archive_path = nullptr;

int CDSConfig::get_status() {
  assert(Universe::is_fully_initialized(), "status is finalized only after Universe is initialized");
  return (is_dumping_archive()              ? IS_DUMPING_ARCHIVE : 0) |
         (is_dumping_static_archive()       ? IS_DUMPING_STATIC_ARCHIVE : 0) |
         (is_logging_lambda_form_invokers() ? IS_LOGGING_LAMBDA_FORM_INVOKERS : 0) |
         (is_using_archive()                ? IS_USING_ARCHIVE : 0);
}


void CDSConfig::initialize() {
  if (is_dumping_static_archive()) {
    if (RequireSharedSpaces) {
      warning("Cannot dump shared archive while using shared archive");
    }
    UseSharedSpaces = false;
  }

  // Initialize shared archive paths which could include both base and dynamic archive paths
  // This must be after set_ergonomics_flags() called so flag UseCompressedOops is set properly.
  //
  // UseSharedSpaces may be disabled if -XX:SharedArchiveFile is invalid.
  if (is_dumping_static_archive() || UseSharedSpaces) {
    init_shared_archive_paths();
  }

  if (!is_dumping_heap()) {
    _is_dumping_full_module_graph = false;
  }
}

char* CDSConfig::default_archive_path() {
  if (_default_archive_path == nullptr) {
    char jvm_path[JVM_MAXPATHLEN];
    os::jvm_path(jvm_path, sizeof(jvm_path));
    char *end = strrchr(jvm_path, *os::file_separator());
    if (end != nullptr) *end = '\0';
    size_t jvm_path_len = strlen(jvm_path);
    size_t file_sep_len = strlen(os::file_separator());
    const size_t len = jvm_path_len + file_sep_len + 20;
    _default_archive_path = NEW_C_HEAP_ARRAY(char, len, mtArguments);
    jio_snprintf(_default_archive_path, len,
                LP64_ONLY(!UseCompressedOops ? "%s%sclasses_nocoops.jsa":) "%s%sclasses.jsa",
                jvm_path, os::file_separator());
  }
  return _default_archive_path;
}

int CDSConfig::num_archives(const char* archive_path) {
  if (archive_path == nullptr) {
    return 0;
  }
  int npaths = 1;
  char* p = (char*)archive_path;
  while (*p != '\0') {
    if (*p == os::path_separator()[0]) {
      npaths++;
    }
    p++;
  }
  return npaths;
}

void CDSConfig::extract_shared_archive_paths(const char* archive_path,
                                             char** base_archive_path,
                                             char** top_archive_path) {
  char* begin_ptr = (char*)archive_path;
  char* end_ptr = strchr((char*)archive_path, os::path_separator()[0]);
  if (end_ptr == nullptr || end_ptr == begin_ptr) {
    vm_exit_during_initialization("Base archive was not specified", archive_path);
  }
  size_t len = end_ptr - begin_ptr;
  char* cur_path = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
  strncpy(cur_path, begin_ptr, len);
  cur_path[len] = '\0';
  *base_archive_path = cur_path;

  begin_ptr = ++end_ptr;
  if (*begin_ptr == '\0') {
    vm_exit_during_initialization("Top archive was not specified", archive_path);
  }
  end_ptr = strchr(begin_ptr, '\0');
  assert(end_ptr != nullptr, "sanity");
  len = end_ptr - begin_ptr;
  cur_path = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
  strncpy(cur_path, begin_ptr, len + 1);
  *top_archive_path = cur_path;
}

void CDSConfig::init_shared_archive_paths() {
  if (ArchiveClassesAtExit != nullptr) {
    assert(!RecordDynamicDumpInfo, "already checked");
    if (is_dumping_static_archive()) {
      vm_exit_during_initialization("-XX:ArchiveClassesAtExit cannot be used with -Xshare:dump");
    }
    check_unsupported_dumping_properties();

    if (os::same_files(default_archive_path(), ArchiveClassesAtExit)) {
      vm_exit_during_initialization(
        "Cannot specify the default CDS archive for -XX:ArchiveClassesAtExit", default_archive_path());
    }
  }

  if (SharedArchiveFile == nullptr) {
    _static_archive_path = default_archive_path();
  } else {
    int archives = num_archives(SharedArchiveFile);
    assert(archives > 0, "must be");

    if (is_dumping_archive() && archives > 1) {
      vm_exit_during_initialization(
        "Cannot have more than 1 archive file specified in -XX:SharedArchiveFile during CDS dumping");
    }

    if (is_dumping_static_archive()) {
      assert(archives == 1, "must be");
      // Static dump is simple: only one archive is allowed in SharedArchiveFile. This file
      // will be overwritten no matter regardless of its contents
      _static_archive_path = os::strdup_check_oom(SharedArchiveFile, mtArguments);
    } else {
      // SharedArchiveFile may specify one or two files. In case (c), the path for base.jsa
      // is read from top.jsa
      //    (a) 1 file:  -XX:SharedArchiveFile=base.jsa
      //    (b) 2 files: -XX:SharedArchiveFile=base.jsa:top.jsa
      //    (c) 2 files: -XX:SharedArchiveFile=top.jsa
      //
      // However, if either RecordDynamicDumpInfo or ArchiveClassesAtExit is used, we do not
      // allow cases (b) and (c). Case (b) is already checked above.

      if (archives > 2) {
        vm_exit_during_initialization(
          "Cannot have more than 2 archive files specified in the -XX:SharedArchiveFile option");
      }
      if (archives == 1) {
        char* base_archive_path = nullptr;
        bool success =
          FileMapInfo::get_base_archive_name_from_header(SharedArchiveFile, &base_archive_path);
        if (!success) {
          // If +AutoCreateSharedArchive and the specified shared archive does not exist,
          // regenerate the dynamic archive base on default archive.
          if (AutoCreateSharedArchive && !os::file_exists(SharedArchiveFile)) {
            enable_dumping_dynamic_archive();
            ArchiveClassesAtExit = const_cast<char *>(SharedArchiveFile);
            _static_archive_path = default_archive_path();
            SharedArchiveFile = nullptr;
          } else {
            if (AutoCreateSharedArchive) {
              warning("-XX:+AutoCreateSharedArchive is unsupported when base CDS archive is not loaded. Run with -Xlog:cds for more info.");
              AutoCreateSharedArchive = false;
            }
            Arguments::no_shared_spaces("invalid archive");
          }
        } else if (base_archive_path == nullptr) {
          // User has specified a single archive, which is a static archive.
          _static_archive_path = const_cast<char *>(SharedArchiveFile);
        } else {
          // User has specified a single archive, which is a dynamic archive.
          _dynamic_archive_path = const_cast<char *>(SharedArchiveFile);
          _static_archive_path = base_archive_path; // has been c-heap allocated.
        }
      } else {
        extract_shared_archive_paths((const char*)SharedArchiveFile,
                                      &_static_archive_path, &_dynamic_archive_path);
        if (_static_archive_path == nullptr) {
          assert(_dynamic_archive_path == nullptr, "must be");
          Arguments::no_shared_spaces("invalid archive");
        }
      }

      if (_dynamic_archive_path != nullptr) {
        // Check for case (c)
        if (RecordDynamicDumpInfo) {
          vm_exit_during_initialization("-XX:+RecordDynamicDumpInfo is unsupported when a dynamic CDS archive is specified in -XX:SharedArchiveFile",
                                        SharedArchiveFile);
        }
        if (ArchiveClassesAtExit != nullptr) {
          vm_exit_during_initialization("-XX:ArchiveClassesAtExit is unsupported when a dynamic CDS archive is specified in -XX:SharedArchiveFile",
                                        SharedArchiveFile);
        }
      }

      if (ArchiveClassesAtExit != nullptr && os::same_files(SharedArchiveFile, ArchiveClassesAtExit)) {
          vm_exit_during_initialization(
            "Cannot have the same archive file specified for -XX:SharedArchiveFile and -XX:ArchiveClassesAtExit",
            SharedArchiveFile);
      }
    }
  }
}

void CDSConfig::check_system_property(const char* key, const char* value) {
  if (Arguments::is_internal_module_property(key)) {
    stop_using_optimized_module_handling();
    log_info(cds)("optimized module handling: disabled due to incompatible property: %s=%s", key, value);
  }
  if (strcmp(key, "jdk.module.showModuleResolution") == 0 ||
      strcmp(key, "jdk.module.validation") == 0 ||
      strcmp(key, "java.system.class.loader") == 0) {
    stop_dumping_full_module_graph();
    stop_using_full_module_graph();
    log_info(cds)("full module graph: disabled due to incompatible property: %s=%s", key, value);
  }
}

static const char* unsupported_properties[] = {
  "jdk.module.limitmods",
  "jdk.module.upgrade.path",
  "jdk.module.patch.0"
};
static const char* unsupported_options[] = {
  "--limit-modules",
  "--upgrade-module-path",
  "--patch-module"
};

void CDSConfig::check_unsupported_dumping_properties() {
  assert(is_dumping_archive(), "this function is only used with CDS dump time");
  assert(ARRAY_SIZE(unsupported_properties) == ARRAY_SIZE(unsupported_options), "must be");
  // If a vm option is found in the unsupported_options array, vm will exit with an error message.
  SystemProperty* sp = Arguments::system_properties();
  while (sp != nullptr) {
    for (uint i = 0; i < ARRAY_SIZE(unsupported_properties); i++) {
      if (strcmp(sp->key(), unsupported_properties[i]) == 0) {
        vm_exit_during_initialization(
          "Cannot use the following option when dumping the shared archive", unsupported_options[i]);
      }
    }
    sp = sp->next();
  }

  // Check for an exploded module build in use with -Xshare:dump.
  if (!Arguments::has_jimage()) {
    vm_exit_during_initialization("Dumping the shared archive is not supported with an exploded module build");
  }
}

bool CDSConfig::check_unsupported_cds_runtime_properties() {
  assert(UseSharedSpaces, "this function is only used with -Xshare:{on,auto}");
  assert(ARRAY_SIZE(unsupported_properties) == ARRAY_SIZE(unsupported_options), "must be");
  if (ArchiveClassesAtExit != nullptr) {
    // dynamic dumping, just return false for now.
    // check_unsupported_dumping_properties() will be called later to check the same set of
    // properties, and will exit the VM with the correct error message if the unsupported properties
    // are used.
    return false;
  }
  for (uint i = 0; i < ARRAY_SIZE(unsupported_properties); i++) {
    if (Arguments::get_property(unsupported_properties[i]) != nullptr) {
      if (RequireSharedSpaces) {
        warning("CDS is disabled when the %s option is specified.", unsupported_options[i]);
      } else {
        log_info(cds)("CDS is disabled when the %s option is specified.", unsupported_options[i]);
      }
      return true;
    }
  }
  return false;
}

bool CDSConfig::check_vm_args_consistency(bool patch_mod_javabase,  bool mode_flag_cmd_line) {
  if (is_dumping_static_archive()) {
    if (!mode_flag_cmd_line) {
      // By default, -Xshare:dump runs in interpreter-only mode, which is required for deterministic archive.
      //
      // If your classlist is large and you don't care about deterministic dumping, you can use
      // -Xshare:dump -Xmixed to improve dumping speed.
      Arguments::set_mode_flags(Arguments::_int);
    } else if (Arguments::mode() == Arguments::_comp) {
      // -Xcomp may use excessive CPU for the test tiers. Also, -Xshare:dump runs a small and fixed set of
      // Java code, so there's not much benefit in running -Xcomp.
      log_info(cds)("reduced -Xcomp to -Xmixed for static dumping");
      Arguments::set_mode_flags(Arguments::_mixed);
    }

    // String deduplication may cause CDS to iterate the strings in different order from one
    // run to another which resulting in non-determinstic CDS archives.
    // Disable UseStringDeduplication while dumping CDS archive.
    UseStringDeduplication = false;
  }

  // RecordDynamicDumpInfo is not compatible with ArchiveClassesAtExit
  if (ArchiveClassesAtExit != nullptr && RecordDynamicDumpInfo) {
    jio_fprintf(defaultStream::output_stream(),
                "-XX:+RecordDynamicDumpInfo cannot be used with -XX:ArchiveClassesAtExit.\n");
    return false;
  }

  if (ArchiveClassesAtExit == nullptr && !RecordDynamicDumpInfo) {
    disable_dumping_dynamic_archive();
  } else {
    enable_dumping_dynamic_archive();
  }

  if (AutoCreateSharedArchive) {
    if (SharedArchiveFile == nullptr) {
      log_warning(cds)("-XX:+AutoCreateSharedArchive requires -XX:SharedArchiveFile");
      return false;
    }
    if (ArchiveClassesAtExit != nullptr) {
      log_warning(cds)("-XX:+AutoCreateSharedArchive does not work with ArchiveClassesAtExit");
      return false;
    }
  }

  if (UseSharedSpaces && patch_mod_javabase) {
    Arguments::no_shared_spaces("CDS is disabled when " JAVA_BASE_NAME " module is patched.");
  }
  if (UseSharedSpaces && check_unsupported_cds_runtime_properties()) {
    UseSharedSpaces = false;
  }

  if (is_dumping_archive()) {
    // Always verify non-system classes during CDS dump
    if (!BytecodeVerificationRemote) {
      BytecodeVerificationRemote = true;
      log_info(cds)("All non-system classes will be verified (-Xverify:remote) during CDS dump time.");
    }
  }

  return true;
}

bool CDSConfig::is_using_archive() {
  return UseSharedSpaces; // TODO: UseSharedSpaces will be eventually replaced by CDSConfig::is_using_archive()
}

bool CDSConfig::is_logging_lambda_form_invokers() {
  return ClassListWriter::is_enabled() || is_dumping_dynamic_archive();
}

void CDSConfig::stop_using_optimized_module_handling() {
  _is_using_optimized_module_handling = false;
  _is_dumping_full_module_graph = false; // This requires is_using_optimized_module_handling()
  _is_using_full_module_graph = false; // This requires is_using_optimized_module_handling()
}

#if INCLUDE_CDS_JAVA_HEAP
bool CDSConfig::is_dumping_heap() {
  // heap dump is not supported in dynamic dump
  return is_dumping_static_archive() && HeapShared::can_write();
}

bool CDSConfig::is_using_full_module_graph() {
  if (ClassLoaderDataShared::is_full_module_graph_loaded()) {
    return true;
  }

  if (!_is_using_full_module_graph) {
    return false;
  }

  if (UseSharedSpaces && ArchiveHeapLoader::can_use()) {
    // Classes used by the archived full module graph are loaded in JVMTI early phase.
    assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
           "CDS should be disabled if early class hooks are enabled");
    return true;
  } else {
    _is_using_full_module_graph = false;
    return false;
  }
}

void CDSConfig::stop_dumping_full_module_graph(const char* reason) {
  if (_is_dumping_full_module_graph) {
    _is_dumping_full_module_graph = false;
    if (reason != nullptr) {
      log_info(cds)("full module graph cannot be dumped: %s", reason);
    }
  }
}

void CDSConfig::stop_using_full_module_graph(const char* reason) {
  assert(!ClassLoaderDataShared::is_full_module_graph_loaded(), "you call this function too late!");
  if (_is_using_full_module_graph) {
    _is_using_full_module_graph = false;
    if (reason != nullptr) {
      log_info(cds)("full module graph cannot be loaded: %s", reason);
    }
  }
}
#endif // INCLUDE_CDS_JAVA_HEAP