| /* |
| * Copyright (c) 2016 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. |
| * |
| */ |
| |
| #ifndef SHARE_VM_GC_SHARED_WORKERMANAGER_HPP |
| #define SHARE_VM_GC_SHARED_WORKERMANAGER_HPP |
| |
| #include "gc/shared/adaptiveSizePolicy.hpp" |
| |
| class WorkerManager : public AllStatic { |
| public: |
| // Create additional workers as needed. |
| // active_workers - number of workers being requested for an upcoming |
| // parallel task. |
| // total_workers - total number of workers. This is the maximum |
| // number possible. |
| // created_workers - number of workers already created. This maybe |
| // less than, equal to, or greater than active workers. If greater than |
| // or equal to active_workers, nothing is done. |
| // worker_type - type of thread. |
| // initializing - true if this is called to get the initial number of |
| // GC workers. |
| // If initializing is true, do a vm exit if the workers cannot be created. |
| // The initializing = true case is for JVM start up and failing to |
| // create all the worker at start should considered a problem so exit. |
| // If initializing = false, there are already some number of worker |
| // threads and a failure would not be optimal but should not be fatal. |
| template <class WorkerType> |
| static uint add_workers (WorkerType* holder, |
| uint active_workers, |
| uint total_workers, |
| uint created_workers, |
| os::ThreadType worker_type, |
| bool initializing) { |
| uint start = created_workers; |
| uint end = MIN2(active_workers, total_workers); |
| for (uint worker_id = start; worker_id < end; worker_id += 1) { |
| WorkerThread* new_worker = NULL; |
| if (initializing || !InjectGCWorkerCreationFailure) { |
| new_worker = holder->install_worker(worker_id); |
| } |
| if (new_worker == NULL || !os::create_thread(new_worker, worker_type)) { |
| log_trace(gc, task)("WorkerManager::add_workers() : " |
| "creation failed due to failed allocation of native %s", |
| new_worker == NULL ? "memory" : "thread"); |
| if (new_worker != NULL) { |
| delete new_worker; |
| } |
| if (initializing) { |
| vm_exit_out_of_memory(0, OOM_MALLOC_ERROR, "Cannot create worker GC thread. Out of system resources."); |
| } |
| break; |
| } |
| created_workers++; |
| os::start_thread(new_worker); |
| } |
| |
| log_trace(gc, task)("WorkerManager::add_workers() : " |
| "created_workers: %u", created_workers); |
| |
| return created_workers; |
| } |
| |
| // Log (at trace level) a change in the number of created workers. |
| template <class WorkerType> |
| static void log_worker_creation(WorkerType* holder, |
| uint previous_created_workers, |
| uint active_workers, |
| uint created_workers, |
| bool initializing) { |
| if (previous_created_workers < created_workers) { |
| const char* initializing_msg = initializing ? "Adding initial" : "Creating additional"; |
| log_trace(gc, task)("%s %s(s) previously created workers %u active workers %u total created workers %u", |
| initializing_msg, holder->group_name(), previous_created_workers, active_workers, created_workers); |
| } |
| } |
| }; |
| #endif // SHARE_VM_GC_SHARED_WORKERMANAGER_HPP |