1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #ifndef SHARE_RUNTIME_THREADS_HPP
27 #define SHARE_RUNTIME_THREADS_HPP
28
29 #include "jni.h"
30 #include "utilities/exceptions.hpp"
31 #include "utilities/globalDefinitions.hpp"
32 #include "utilities/macros.hpp"
33
34 class JavaThread;
35 class Metadata;
36 class MetadataClosure;
37 class OopClosure;
38 class Thread;
39 class ThreadClosure;
40 class ThreadsList;
41 class outputStream;
42
43 // The active thread queue. It also keeps track of the current used
44 // thread priorities.
45 class Threads: AllStatic {
46 friend class VMStructs;
47 private:
48 static int _number_of_threads;
49 static int _number_of_non_daemon_threads;
50 static int _return_code;
51 static uintx _thread_claim_token;
52 #ifdef ASSERT
53 static bool _vm_complete;
54 #endif
55
56 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
57 static void initialize_jsr292_core_classes(TRAPS);
58
59 public:
60 // Thread management
61 // force_daemon is a concession to JNI, where we may need to add a
62 // thread to the thread list before allocating its thread object
63 static void add(JavaThread* p, bool force_daemon = false);
64 static void remove(JavaThread* p, bool is_daemon);
65 static void non_java_threads_do(ThreadClosure* tc);
66 static void java_threads_do(ThreadClosure* tc);
67 static void threads_do(ThreadClosure* tc);
68 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
69
70 // Initializes the vm and creates the vm thread
71 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
72 static void convert_vm_init_libraries_to_agents();
73 static void create_vm_init_libraries();
74 static void create_vm_init_agents();
75 static void shutdown_vm_agents();
76 static void destroy_vm();
77 // Supported VM versions via JNI
78 // Includes JNI_VERSION_1_1
79 static jboolean is_supported_jni_version_including_1_1(jint version);
80 // Does not include JNI_VERSION_1_1
81 static jboolean is_supported_jni_version(jint version);
82
83 private:
84 // The "thread claim token" provides a way for threads to be claimed
85 // by parallel worker tasks.
86 //
87 // Each thread contains a "token" field. A task will claim the
88 // thread only if its token is different from the global token,
89 // which is updated by calling change_thread_claim_token(). When
90 // a thread is claimed, it's token is set to the global token value
91 // so other threads in the same iteration pass won't claim it.
92 //
93 // For this to work change_thread_claim_token() needs to be called
94 // exactly once in sequential code before starting parallel tasks
95 // that should claim threads.
96 //
97 // New threads get their token set to 0 and change_thread_claim_token()
98 // never sets the global token to 0.
99 static uintx thread_claim_token() { return _thread_claim_token; }
100
101 public:
102 static void change_thread_claim_token();
103 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
104
105 // Apply "f->do_oop" to all root oops in all threads.
106 // This version may only be called by sequential code.
107 static void oops_do(OopClosure* f, NMethodClosure* cf);
108 // This version may be called by sequential or parallel code.
109 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, NMethodClosure* cf);
110
111 // RedefineClasses support
112 static void metadata_do(MetadataClosure* f);
113 static void metadata_handles_do(void f(Metadata*));
114
115 #ifdef ASSERT
116 static bool is_vm_complete() { return _vm_complete; }
117 #endif // ASSERT
118
119 // Verification
120 static void verify();
121 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info);
122 static void print(bool print_stacks, bool internal_format) {
123 // this function is only used by debug.cpp
124 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */);
125 }
126 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
127 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
128 int buflen, bool* found_current);
129 // Print threads busy compiling, and returns the number of printed threads.
130 static unsigned print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false);
131
132 // Get Java threads that are waiting to enter or re-enter the specified monitor.
133 // Java threads that are executing mounted virtual threads are not included.
134 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
135 int count, address monitor);
136
137 // Get owning Java thread from the basicLock address.
138 static JavaThread *owning_thread_from_stacklock(ThreadsList * t_list, address basicLock);
139
140 static JavaThread* owning_thread_from_object(ThreadsList* t_list, oop obj);
141 static JavaThread* owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* owner);
142
143 // Number of threads on the active threads list
144 static int number_of_threads() { return _number_of_threads; }
145 // Number of non-daemon threads on the active threads list
146 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
147
148 struct Test; // For private gtest access.
149 };
150
151 #endif // SHARE_RUNTIME_THREADS_HPP