hotspot/src/share/vm/prims/jvmtiManageCapabilities.cpp
author ysr
Thu, 03 Dec 2009 15:01:57 -0800
changeset 4461 c17c526d36ef
parent 1 489c9b5090e2
child 4448 d6ec2737186c
permissions -rw-r--r--
6906727: UseCompressedOops: some card-marking fixes related to object arrays Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17). Reviewed-by: kvn, coleenp, jmasa

/*
 * Copyright 2003-2006 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */
# include "incls/_precompiled.incl"
# include "incls/_jvmtiManageCapabilities.cpp.incl"

static const jint CAPA_SIZE = (JVMTI_INTERNAL_CAPABILITY_COUNT + 7) / 8;

  // capabilities which are always potentially available
jvmtiCapabilities JvmtiManageCapabilities::always_capabilities;

  // capabilities which are potentially available during OnLoad
jvmtiCapabilities JvmtiManageCapabilities::onload_capabilities;

  // capabilities which are always potentially available
  // but to only one environment
jvmtiCapabilities JvmtiManageCapabilities::always_solo_capabilities;

  // capabilities which are potentially available during OnLoad
  // but to only one environment
jvmtiCapabilities JvmtiManageCapabilities::onload_solo_capabilities;

  // remaining capabilities which are always potentially available
  // but to only one environment
jvmtiCapabilities JvmtiManageCapabilities::always_solo_remaining_capabilities;

  // remaining capabilities which are potentially available during OnLoad
  // but to only one environment
jvmtiCapabilities JvmtiManageCapabilities::onload_solo_remaining_capabilities;

  // all capabilities ever acquired
jvmtiCapabilities JvmtiManageCapabilities::acquired_capabilities;

void JvmtiManageCapabilities::initialize() {
  always_capabilities = init_always_capabilities();
  if (JvmtiEnv::get_phase() != JVMTI_PHASE_ONLOAD) {
    recompute_always_capabilities();
  }
  onload_capabilities = init_onload_capabilities();
  always_solo_capabilities = init_always_solo_capabilities();
  onload_solo_capabilities = init_onload_solo_capabilities();
  always_solo_remaining_capabilities = init_always_solo_capabilities();
  onload_solo_remaining_capabilities = init_onload_solo_capabilities();
  memset(&acquired_capabilities, 0, sizeof(acquired_capabilities));
}

// if the capability sets are initialized in the onload phase then
// it happens before class data sharing (CDS) is initialized. If it
// turns out that CDS gets disabled then we must adjust the always
// capabilities. To ensure a consistent view of the capabililties
// anything we add here should already be in the onload set.
void JvmtiManageCapabilities::recompute_always_capabilities() {
  if (!UseSharedSpaces) {
    jvmtiCapabilities jc = always_capabilities;
    jc.can_generate_all_class_hook_events = 1;
    always_capabilities = jc;
  }
}


// corresponding init functions
jvmtiCapabilities JvmtiManageCapabilities::init_always_capabilities() {
  jvmtiCapabilities jc;

  memset(&jc, 0, sizeof(jc));
  jc.can_get_bytecodes = 1;
  jc.can_signal_thread = 1;
  jc.can_get_source_file_name = 1;
  jc.can_get_line_numbers = 1;
  jc.can_get_synthetic_attribute = 1;
  jc.can_get_monitor_info = 1;
  jc.can_get_constant_pool = 1;
  jc.can_generate_monitor_events = 1;
  jc.can_generate_garbage_collection_events = 1;
  jc.can_generate_compiled_method_load_events = 1;
  jc.can_generate_native_method_bind_events = 1;
  jc.can_generate_vm_object_alloc_events = 1;
  if (os::is_thread_cpu_time_supported()) {
    jc.can_get_current_thread_cpu_time = 1;
    jc.can_get_thread_cpu_time = 1;
  }
  jc.can_redefine_classes = 1;
  jc.can_redefine_any_class = 1;
  jc.can_retransform_classes = 1;
  jc.can_retransform_any_class = 1;
  jc.can_set_native_method_prefix = 1;
  jc.can_tag_objects = 1;
  jc.can_generate_object_free_events = 1;
  jc.can_generate_resource_exhaustion_heap_events = 1;
  jc.can_generate_resource_exhaustion_threads_events = 1;
  return jc;
}

jvmtiCapabilities JvmtiManageCapabilities::init_onload_capabilities() {
  jvmtiCapabilities jc;

  memset(&jc, 0, sizeof(jc));
  jc.can_pop_frame = 1;
  jc.can_force_early_return = 1;
  jc.can_get_source_debug_extension = 1;
  jc.can_access_local_variables = 1;
  jc.can_maintain_original_method_order = 1;
  jc.can_generate_all_class_hook_events = 1;
  jc.can_generate_single_step_events = 1;
  jc.can_generate_exception_events = 1;
  jc.can_generate_frame_pop_events = 1;
  jc.can_generate_method_entry_events = 1;
  jc.can_generate_method_exit_events = 1;
  jc.can_get_owned_monitor_info = 1;
  jc.can_get_owned_monitor_stack_depth_info = 1;
  jc.can_get_current_contended_monitor = 1;
  // jc.can_get_monitor_info = 1;
  jc.can_tag_objects = 1;                 // TODO: this should have been removed
  jc.can_generate_object_free_events = 1; // TODO: this should have been removed
  return jc;
}


jvmtiCapabilities JvmtiManageCapabilities::init_always_solo_capabilities() {
  jvmtiCapabilities jc;

  memset(&jc, 0, sizeof(jc));
  jc.can_suspend = 1;
  return jc;
}


jvmtiCapabilities JvmtiManageCapabilities::init_onload_solo_capabilities() {
  jvmtiCapabilities jc;

  memset(&jc, 0, sizeof(jc));
  jc.can_generate_field_modification_events = 1;
  jc.can_generate_field_access_events = 1;
  jc.can_generate_breakpoint_events = 1;
  return jc;
}


jvmtiCapabilities *JvmtiManageCapabilities::either(const jvmtiCapabilities *a, const jvmtiCapabilities *b,
                                                   jvmtiCapabilities *result) {
  char *ap = (char *)a;
  char *bp = (char *)b;
  char *resultp = (char *)result;

  for (int i = 0; i < CAPA_SIZE; ++i) {
    *resultp++ = *ap++ | *bp++;
  }

  return result;
}


jvmtiCapabilities *JvmtiManageCapabilities::both(const jvmtiCapabilities *a, const jvmtiCapabilities *b,
                                                    jvmtiCapabilities *result) {
  char *ap = (char *)a;
  char *bp = (char *)b;
  char *resultp = (char *)result;

  for (int i = 0; i < CAPA_SIZE; ++i) {
    *resultp++ = *ap++ & *bp++;
  }

  return result;
}


jvmtiCapabilities *JvmtiManageCapabilities::exclude(const jvmtiCapabilities *a, const jvmtiCapabilities *b,
                                                    jvmtiCapabilities *result) {
  char *ap = (char *)a;
  char *bp = (char *)b;
  char *resultp = (char *)result;

  for (int i = 0; i < CAPA_SIZE; ++i) {
    *resultp++ = *ap++ & ~*bp++;
  }

  return result;
}


bool JvmtiManageCapabilities::has_some(const jvmtiCapabilities *a) {
  char *ap = (char *)a;

  for (int i = 0; i < CAPA_SIZE; ++i) {
    if (*ap++ != 0) {
      return true;
    }
  }

  return false;
}


void JvmtiManageCapabilities::copy_capabilities(const jvmtiCapabilities *from, jvmtiCapabilities *to) {
  char *ap = (char *)from;
  char *resultp = (char *)to;

  for (int i = 0; i < CAPA_SIZE; ++i) {
    *resultp++ = *ap++;
  }
}


void JvmtiManageCapabilities::get_potential_capabilities(const jvmtiCapabilities *current,
                                                         const jvmtiCapabilities *prohibited,
                                                         jvmtiCapabilities *result) {
  // exclude prohibited capabilities, must be before adding current
  exclude(&always_capabilities, prohibited, result);

  // must include current since it may possess solo capabilities and now prohibited
  either(result, current, result);

  // add other remaining
  either(result, &always_solo_remaining_capabilities, result);

  // if this is during OnLoad more capabilities are available
  if (JvmtiEnv::get_phase() == JVMTI_PHASE_ONLOAD) {
    either(result, &onload_capabilities, result);
    either(result, &onload_solo_remaining_capabilities, result);
  }
}

jvmtiError JvmtiManageCapabilities::add_capabilities(const jvmtiCapabilities *current,
                                                     const jvmtiCapabilities *prohibited,
                                                     const jvmtiCapabilities *desired,
                                                     jvmtiCapabilities *result) {
  // check that the capabilities being added are potential capabilities
  jvmtiCapabilities temp;
  get_potential_capabilities(current, prohibited, &temp);
  if (has_some(exclude(desired, &temp, &temp))) {
    return JVMTI_ERROR_NOT_AVAILABLE;
  }

  // add to the set of ever acquired capabilities
  either(&acquired_capabilities, desired, &acquired_capabilities);

  // onload capabilities that got added are now permanent - so, also remove from onload
  both(&onload_capabilities, desired, &temp);
  either(&always_capabilities, &temp, &always_capabilities);
  exclude(&onload_capabilities, &temp, &onload_capabilities);

  // same for solo capabilities (transferred capabilities in the remaining sets handled as part of standard grab - below)
  both(&onload_solo_capabilities, desired, &temp);
  either(&always_solo_capabilities, &temp, &always_solo_capabilities);
  exclude(&onload_solo_capabilities, &temp, &onload_solo_capabilities);

  // remove solo capabilities that are now taken
  exclude(&always_solo_remaining_capabilities, desired, &always_solo_remaining_capabilities);
  exclude(&onload_solo_remaining_capabilities, desired, &onload_solo_remaining_capabilities);

  // return the result
  either(current, desired, result);

  update();

  return JVMTI_ERROR_NONE;
}


void JvmtiManageCapabilities::relinquish_capabilities(const jvmtiCapabilities *current,
                                                      const jvmtiCapabilities *unwanted,
                                                      jvmtiCapabilities *result) {
  jvmtiCapabilities to_trash;
  jvmtiCapabilities temp;

  // can't give up what you don't have
  both(current, unwanted, &to_trash);

  // restore solo capabilities but only those that belong
  either(&always_solo_remaining_capabilities, both(&always_solo_capabilities, &to_trash, &temp),
         &always_solo_remaining_capabilities);
  either(&onload_solo_remaining_capabilities, both(&onload_solo_capabilities, &to_trash, &temp),
         &onload_solo_remaining_capabilities);

  update();

  // return the result
  exclude(current, unwanted, result);
}


void JvmtiManageCapabilities::update() {
  jvmtiCapabilities avail;

  // all capabilities
  either(&always_capabilities, &always_solo_capabilities, &avail);

  bool interp_events =
    avail.can_generate_field_access_events ||
    avail.can_generate_field_modification_events ||
    avail.can_generate_single_step_events ||
    avail.can_generate_frame_pop_events ||
    avail.can_generate_method_entry_events ||
    avail.can_generate_method_exit_events;
  bool enter_all_methods =
    interp_events ||
    avail.can_generate_breakpoint_events;
  UseFastEmptyMethods = !enter_all_methods;
  UseFastAccessorMethods = !enter_all_methods;

  if (avail.can_generate_breakpoint_events) {
    RewriteFrequentPairs = false;
  }

  // If can_redefine_classes is enabled in the onload phase then we know that the
  // dependency information recorded by the compiler is complete.
  if ((avail.can_redefine_classes || avail.can_retransform_classes) &&
      JvmtiEnv::get_phase() == JVMTI_PHASE_ONLOAD) {
    JvmtiExport::set_all_dependencies_are_recorded(true);
  }

  JvmtiExport::set_can_get_source_debug_extension(avail.can_get_source_debug_extension);
  JvmtiExport::set_can_examine_or_deopt_anywhere(
    avail.can_generate_breakpoint_events ||
    interp_events ||
    avail.can_redefine_classes ||
    avail.can_retransform_classes ||
    avail.can_access_local_variables ||
    avail.can_get_owned_monitor_info ||
    avail.can_get_current_contended_monitor ||
    avail.can_get_monitor_info ||
    avail.can_get_owned_monitor_stack_depth_info);
  JvmtiExport::set_can_maintain_original_method_order(avail.can_maintain_original_method_order);
  JvmtiExport::set_can_post_interpreter_events(interp_events);
  JvmtiExport::set_can_hotswap_or_post_breakpoint(
    avail.can_generate_breakpoint_events ||
    avail.can_redefine_classes ||
    avail.can_retransform_classes);
  JvmtiExport::set_can_modify_any_class(
    avail.can_generate_breakpoint_events ||
    avail.can_generate_all_class_hook_events);
  JvmtiExport::set_can_walk_any_space(
    avail.can_tag_objects);   // disable sharing in onload phase
  JvmtiExport::set_can_access_local_variables(
    avail.can_access_local_variables  ||
    avail.can_redefine_classes ||
    avail.can_retransform_classes);
  JvmtiExport::set_can_post_exceptions(
    avail.can_generate_exception_events ||
    avail.can_generate_frame_pop_events ||
    avail.can_generate_method_exit_events);
  JvmtiExport::set_can_post_breakpoint(avail.can_generate_breakpoint_events);
  JvmtiExport::set_can_post_field_access(avail.can_generate_field_access_events);
  JvmtiExport::set_can_post_field_modification(avail.can_generate_field_modification_events);
  JvmtiExport::set_can_post_method_entry(avail.can_generate_method_entry_events);
  JvmtiExport::set_can_post_method_exit(avail.can_generate_method_exit_events ||
                                        avail.can_generate_frame_pop_events);
  JvmtiExport::set_can_pop_frame(avail.can_pop_frame);
  JvmtiExport::set_can_force_early_return(avail.can_force_early_return);
  JvmtiExport::set_should_clean_up_heap_objects(avail.can_generate_breakpoint_events);
}

#ifndef PRODUCT

void JvmtiManageCapabilities:: print(const jvmtiCapabilities* cap) {
  tty->print_cr("----- capabilities -----");
  if (cap->can_tag_objects)
    tty->print_cr("can_tag_objects");
  if (cap->can_generate_field_modification_events)
    tty->print_cr("can_generate_field_modification_events");
  if (cap->can_generate_field_access_events)
    tty->print_cr("can_generate_field_access_events");
  if (cap->can_get_bytecodes)
    tty->print_cr("can_get_bytecodes");
  if (cap->can_get_synthetic_attribute)
    tty->print_cr("can_get_synthetic_attribute");
  if (cap->can_get_owned_monitor_info)
    tty->print_cr("can_get_owned_monitor_info");
  if (cap->can_get_current_contended_monitor)
    tty->print_cr("can_get_current_contended_monitor");
  if (cap->can_get_monitor_info)
    tty->print_cr("can_get_monitor_info");
  if (cap->can_get_constant_pool)
    tty->print_cr("can_get_constant_pool");
  if (cap->can_pop_frame)
    tty->print_cr("can_pop_frame");
  if (cap->can_force_early_return)
    tty->print_cr("can_force_early_return");
  if (cap->can_redefine_classes)
    tty->print_cr("can_redefine_classes");
  if (cap->can_retransform_classes)
    tty->print_cr("can_retransform_classes");
  if (cap->can_signal_thread)
    tty->print_cr("can_signal_thread");
  if (cap->can_get_source_file_name)
    tty->print_cr("can_get_source_file_name");
  if (cap->can_get_line_numbers)
    tty->print_cr("can_get_line_numbers");
  if (cap->can_get_source_debug_extension)
    tty->print_cr("can_get_source_debug_extension");
  if (cap->can_access_local_variables)
    tty->print_cr("can_access_local_variables");
  if (cap->can_maintain_original_method_order)
    tty->print_cr("can_maintain_original_method_order");
  if (cap->can_generate_single_step_events)
    tty->print_cr("can_generate_single_step_events");
  if (cap->can_generate_exception_events)
    tty->print_cr("can_generate_exception_events");
  if (cap->can_generate_frame_pop_events)
    tty->print_cr("can_generate_frame_pop_events");
  if (cap->can_generate_breakpoint_events)
    tty->print_cr("can_generate_breakpoint_events");
  if (cap->can_suspend)
    tty->print_cr("can_suspend");
  if (cap->can_redefine_any_class )
    tty->print_cr("can_redefine_any_class");
  if (cap->can_retransform_any_class )
    tty->print_cr("can_retransform_any_class");
  if (cap->can_get_current_thread_cpu_time)
    tty->print_cr("can_get_current_thread_cpu_time");
  if (cap->can_get_thread_cpu_time)
    tty->print_cr("can_get_thread_cpu_time");
  if (cap->can_generate_method_entry_events)
    tty->print_cr("can_generate_method_entry_events");
  if (cap->can_generate_method_exit_events)
    tty->print_cr("can_generate_method_exit_events");
  if (cap->can_generate_all_class_hook_events)
    tty->print_cr("can_generate_all_class_hook_events");
  if (cap->can_generate_compiled_method_load_events)
    tty->print_cr("can_generate_compiled_method_load_events");
  if (cap->can_generate_monitor_events)
    tty->print_cr("can_generate_monitor_events");
  if (cap->can_generate_vm_object_alloc_events)
    tty->print_cr("can_generate_vm_object_alloc_events");
  if (cap->can_generate_native_method_bind_events)
    tty->print_cr("can_generate_native_method_bind_events");
  if (cap->can_generate_garbage_collection_events)
    tty->print_cr("can_generate_garbage_collection_events");
  if (cap->can_generate_object_free_events)
    tty->print_cr("can_generate_object_free_events");
  if (cap->can_generate_resource_exhaustion_heap_events)
    tty->print_cr("can_generate_resource_exhaustion_heap_events");
  if (cap->can_generate_resource_exhaustion_threads_events)
    tty->print_cr("can_generate_resource_exhaustion_threads_events");
}

#endif