| /* |
| * Copyright (c) 2017, 2019, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "logging/log.hpp" |
| #include "runtime/globals.hpp" |
| #include "runtime/os.hpp" |
| #include "runtime/safepointMechanism.inline.hpp" |
| #include "services/memTracker.hpp" |
| #include "utilities/globalDefinitions.hpp" |
| |
| SafepointMechanism::PollingType SafepointMechanism::_polling_type = SafepointMechanism::_global_page_poll; |
| void* SafepointMechanism::_poll_armed_value; |
| void* SafepointMechanism::_poll_disarmed_value; |
| |
| void SafepointMechanism::default_initialize() { |
| if (ThreadLocalHandshakes) { |
| set_uses_thread_local_poll(); |
| |
| // Poll bit values |
| intptr_t poll_armed_value = poll_bit(); |
| intptr_t poll_disarmed_value = 0; |
| |
| #ifdef USE_POLL_BIT_ONLY |
| if (!USE_POLL_BIT_ONLY) |
| #endif |
| { |
| // Polling page |
| const size_t page_size = os::vm_page_size(); |
| const size_t allocation_size = 2 * page_size; |
| char* polling_page = os::reserve_memory(allocation_size, NULL, page_size); |
| os::commit_memory_or_exit(polling_page, allocation_size, false, "Unable to commit Safepoint polling page"); |
| MemTracker::record_virtual_memory_type((address)polling_page, mtSafepoint); |
| |
| char* bad_page = polling_page; |
| char* good_page = polling_page + page_size; |
| |
| os::protect_memory(bad_page, page_size, os::MEM_PROT_NONE); |
| os::protect_memory(good_page, page_size, os::MEM_PROT_READ); |
| |
| log_info(os)("SafePoint Polling address, bad (protected) page:" INTPTR_FORMAT ", good (unprotected) page:" INTPTR_FORMAT, p2i(bad_page), p2i(good_page)); |
| os::set_polling_page((address)(bad_page)); |
| |
| // Poll address values |
| intptr_t bad_page_val = reinterpret_cast<intptr_t>(bad_page), |
| good_page_val = reinterpret_cast<intptr_t>(good_page); |
| poll_armed_value |= bad_page_val; |
| poll_disarmed_value |= good_page_val; |
| } |
| |
| _poll_armed_value = reinterpret_cast<void*>(poll_armed_value); |
| _poll_disarmed_value = reinterpret_cast<void*>(poll_disarmed_value); |
| } else { |
| const size_t page_size = os::vm_page_size(); |
| char* polling_page = os::reserve_memory(page_size, NULL, page_size); |
| os::commit_memory_or_exit(polling_page, page_size, false, "Unable to commit Safepoint polling page"); |
| os::protect_memory(polling_page, page_size, os::MEM_PROT_READ); |
| MemTracker::record_virtual_memory_type((address)polling_page, mtSafepoint); |
| |
| log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page)); |
| os::set_polling_page((address)(polling_page)); |
| } |
| } |
| |
| void SafepointMechanism::block_if_requested_slow(JavaThread *thread) { |
| // local poll already checked, if used. |
| if (global_poll()) { |
| SafepointSynchronize::block(thread); |
| } |
| if (uses_thread_local_poll() && thread->has_handshake()) { |
| thread->handshake_process_by_self(); |
| } |
| } |
| |
| void SafepointMechanism::initialize_header(JavaThread* thread) { |
| disarm_local_poll(thread); |
| } |
| |
| void SafepointMechanism::initialize_serialize_page() { |
| if (!UseMembar) { |
| const size_t page_size = os::vm_page_size(); |
| char* serialize_page = os::reserve_memory(page_size, NULL, page_size); |
| os::commit_memory_or_exit(serialize_page, page_size, false, "Unable to commit memory serialization page"); |
| log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(serialize_page)); |
| os::set_memory_serialize_page((address)(serialize_page)); |
| } |
| } |
| |
| void SafepointMechanism::initialize() { |
| pd_initialize(); |
| initialize_serialize_page(); |
| } |