view src/share/vm/prims/jvmtiManageCapabilities.cpp @ 452:00b023ae2d78

6722113: CMS: Incorrect overflow handling during precleaning of Reference lists Summary: When we encounter marking stack overflow during precleaning of Reference lists, we were using the overflow list mechanism, which can cause problems on account of mutating the mark word of the header because of conflicts with mutator accesses and updates of that field. Instead we should use the usual mechanism for overflow handling in concurrent phases, namely dirtying of the card on which the overflowed object lies. Since precleaning effectively does a form of discovered list processing, albeit with discovery enabled, we needed to adjust some code to be correct in the face of interleaved processing and discovery. Reviewed-by: apetrusenko, jcoomes
author ysr
date Thu, 20 Nov 2008 12:27:41 -0800
parents a61af66fc99e
children 8e7adf982378
line wrap: on
line source

/*
 * 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