Thu, 27 Feb 2020 05:40:59 +0000
8187078: -XX:+VerifyOops finds numerous problems when running JPRT
Reviewed-by: andrew
1 /*
2 * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "runtime/arguments.hpp"
28 #include "runtime/java.hpp"
29 #include "runtime/mutex.hpp"
30 #include "runtime/mutexLocker.hpp"
31 #include "runtime/orderAccess.inline.hpp"
32 #include "runtime/os.hpp"
33 #include "runtime/perfData.hpp"
34 #include "runtime/perfMemory.hpp"
35 #include "runtime/statSampler.hpp"
36 #include "utilities/globalDefinitions.hpp"
38 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
40 // Prefix of performance data file.
41 const char PERFDATA_NAME[] = "hsperfdata";
43 // Add 1 for the '_' character between PERFDATA_NAME and pid. The '\0' terminating
44 // character will be included in the sizeof(PERFDATA_NAME) operation.
45 static const size_t PERFDATA_FILENAME_LEN = sizeof(PERFDATA_NAME) +
46 UINT_CHARS + 1;
48 char* PerfMemory::_start = NULL;
49 char* PerfMemory::_end = NULL;
50 char* PerfMemory::_top = NULL;
51 size_t PerfMemory::_capacity = 0;
52 jint PerfMemory::_initialized = false;
53 PerfDataPrologue* PerfMemory::_prologue = NULL;
55 void perfMemory_init() {
57 if (!UsePerfData) return;
59 PerfMemory::initialize();
60 }
62 void perfMemory_exit() {
64 if (!UsePerfData) return;
65 if (!PerfMemory::is_initialized()) return;
67 // if the StatSampler is active, then we don't want to remove
68 // resources it may be dependent on. Typically, the StatSampler
69 // is disengaged from the watcher thread when this method is called,
70 // but it is not disengaged if this method is invoked during a
71 // VM abort.
72 //
73 if (!StatSampler::is_active())
74 PerfDataManager::destroy();
76 // remove the persistent external resources, if any. this method
77 // does not unmap or invalidate any virtual memory allocated during
78 // initialization.
79 //
80 PerfMemory::destroy();
81 }
83 void PerfMemory::initialize() {
85 if (_prologue != NULL)
86 // initialization already performed
87 return;
89 size_t capacity = align_size_up(PerfDataMemorySize,
90 os::vm_allocation_granularity());
92 if (PerfTraceMemOps) {
93 tty->print("PerfDataMemorySize = " SIZE_FORMAT ","
94 " os::vm_allocation_granularity = " SIZE_FORMAT ","
95 " adjusted size = " SIZE_FORMAT "\n",
96 PerfDataMemorySize,
97 os::vm_allocation_granularity(),
98 capacity);
99 }
101 // allocate PerfData memory region
102 create_memory_region(capacity);
104 if (_start == NULL) {
106 // the PerfMemory region could not be created as desired. Rather
107 // than terminating the JVM, we revert to creating the instrumentation
108 // on the C heap. When running in this mode, external monitoring
109 // clients cannot attach to and monitor this JVM.
110 //
111 // the warning is issued only in debug mode in order to avoid
112 // additional output to the stdout or stderr output streams.
113 //
114 if (PrintMiscellaneous && Verbose) {
115 warning("Could not create PerfData Memory region, reverting to malloc");
116 }
118 _prologue = NEW_C_HEAP_OBJ(PerfDataPrologue, mtInternal);
119 }
120 else {
122 // the PerfMemory region was created as expected.
124 if (PerfTraceMemOps) {
125 tty->print("PerfMemory created: address = " INTPTR_FORMAT ","
126 " size = " SIZE_FORMAT "\n",
127 (void*)_start,
128 _capacity);
129 }
131 _prologue = (PerfDataPrologue *)_start;
132 _end = _start + _capacity;
133 _top = _start + sizeof(PerfDataPrologue);
134 }
136 assert(_prologue != NULL, "prologue pointer must be initialized");
138 #ifdef VM_LITTLE_ENDIAN
139 _prologue->magic = (jint)0xc0c0feca;
140 _prologue->byte_order = PERFDATA_LITTLE_ENDIAN;
141 #else
142 _prologue->magic = (jint)0xcafec0c0;
143 _prologue->byte_order = PERFDATA_BIG_ENDIAN;
144 #endif
146 _prologue->major_version = PERFDATA_MAJOR_VERSION;
147 _prologue->minor_version = PERFDATA_MINOR_VERSION;
148 _prologue->accessible = 0;
150 _prologue->entry_offset = sizeof(PerfDataPrologue);
151 _prologue->num_entries = 0;
152 _prologue->used = 0;
153 _prologue->overflow = 0;
154 _prologue->mod_time_stamp = 0;
156 OrderAccess::release_store(&_initialized, 1);
157 }
159 void PerfMemory::destroy() {
161 if (_prologue == NULL) return;
163 if (_start != NULL && _prologue->overflow != 0) {
165 // This state indicates that the contiguous memory region exists and
166 // that it wasn't large enough to hold all the counters. In this case,
167 // we output a warning message to the user on exit if the -XX:+Verbose
168 // flag is set (a debug only flag). External monitoring tools can detect
169 // this condition by monitoring the _prologue->overflow word.
170 //
171 // There are two tunables that can help resolve this issue:
172 // - increase the size of the PerfMemory with -XX:PerfDataMemorySize=<n>
173 // - decrease the maximum string constant length with
174 // -XX:PerfMaxStringConstLength=<n>
175 //
176 if (PrintMiscellaneous && Verbose) {
177 warning("PerfMemory Overflow Occurred.\n"
178 "\tCapacity = " SIZE_FORMAT " bytes"
179 " Used = " SIZE_FORMAT " bytes"
180 " Overflow = " INT32_FORMAT " bytes"
181 "\n\tUse -XX:PerfDataMemorySize=<size> to specify larger size.",
182 PerfMemory::capacity(),
183 PerfMemory::used(),
184 _prologue->overflow);
185 }
186 }
188 if (_start != NULL) {
190 // this state indicates that the contiguous memory region was successfully
191 // and that persistent resources may need to be cleaned up. This is
192 // expected to be the typical condition.
193 //
194 delete_memory_region();
195 }
197 _start = NULL;
198 _end = NULL;
199 _top = NULL;
200 _prologue = NULL;
201 _capacity = 0;
202 }
204 // allocate an aligned block of memory from the PerfData memory
205 // region. This method assumes that the PerfData memory region
206 // was aligned on a double word boundary when created.
207 //
208 char* PerfMemory::alloc(size_t size) {
210 if (!UsePerfData) return NULL;
212 MutexLocker ml(PerfDataMemAlloc_lock);
214 assert(_prologue != NULL, "called before initialization");
216 // check that there is enough memory for this request
217 if ((_top + size) >= _end) {
219 _prologue->overflow += (jint)size;
221 return NULL;
222 }
224 char* result = _top;
226 _top += size;
228 assert(contains(result), "PerfData memory pointer out of range");
230 _prologue->used = (jint)used();
231 _prologue->num_entries = _prologue->num_entries + 1;
233 return result;
234 }
236 void PerfMemory::mark_updated() {
237 if (!UsePerfData) return;
239 _prologue->mod_time_stamp = os::elapsed_counter();
240 }
242 // Returns the complete path including the file name of performance data file.
243 // Caller is expected to release the allocated memory.
244 char* PerfMemory::get_perfdata_file_path() {
245 char* dest_file = NULL;
247 if (PerfDataSaveFile != NULL) {
248 // dest_file_name stores the validated file name if file_name
249 // contains %p which will be replaced by pid.
250 dest_file = NEW_C_HEAP_ARRAY(char, JVM_MAXPATHLEN, mtInternal);
251 if(!Arguments::copy_expand_pid(PerfDataSaveFile, strlen(PerfDataSaveFile),
252 dest_file, JVM_MAXPATHLEN)) {
253 FREE_C_HEAP_ARRAY(char, dest_file, mtInternal);
254 if (PrintMiscellaneous && Verbose) {
255 warning("Invalid performance data file path name specified, "\
256 "fall back to a default name");
257 }
258 } else {
259 return dest_file;
260 }
261 }
262 // create the name of the file for retaining the instrumentation memory.
263 dest_file = NEW_C_HEAP_ARRAY(char, PERFDATA_FILENAME_LEN, mtInternal);
264 jio_snprintf(dest_file, PERFDATA_FILENAME_LEN,
265 "%s_%d", PERFDATA_NAME, os::current_process_id());
267 return dest_file;
268 }