Thu, 02 Feb 2012 16:05:17 -0800
6679764: enable parallel compaction by default
Reviewed-by: phh, jmasa
1 /*
2 * Copyright (c) 1997, 2012, 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.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "classfile/javaAssertions.hpp"
27 #include "compiler/compilerOracle.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "memory/cardTableRS.hpp"
30 #include "memory/referenceProcessor.hpp"
31 #include "memory/universe.inline.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "prims/jvmtiExport.hpp"
34 #include "runtime/arguments.hpp"
35 #include "runtime/globals_extension.hpp"
36 #include "runtime/java.hpp"
37 #include "services/management.hpp"
38 #include "utilities/defaultStream.hpp"
39 #include "utilities/taskqueue.hpp"
40 #ifdef TARGET_OS_FAMILY_linux
41 # include "os_linux.inline.hpp"
42 #endif
43 #ifdef TARGET_OS_FAMILY_solaris
44 # include "os_solaris.inline.hpp"
45 #endif
46 #ifdef TARGET_OS_FAMILY_windows
47 # include "os_windows.inline.hpp"
48 #endif
49 #ifdef TARGET_OS_FAMILY_bsd
50 # include "os_bsd.inline.hpp"
51 #endif
52 #ifndef SERIALGC
53 #include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
54 #endif
56 // Note: This is a special bug reporting site for the JVM
57 #define DEFAULT_VENDOR_URL_BUG "http://bugreport.sun.com/bugreport/crash.jsp"
58 #define DEFAULT_JAVA_LAUNCHER "generic"
60 char** Arguments::_jvm_flags_array = NULL;
61 int Arguments::_num_jvm_flags = 0;
62 char** Arguments::_jvm_args_array = NULL;
63 int Arguments::_num_jvm_args = 0;
64 char* Arguments::_java_command = NULL;
65 SystemProperty* Arguments::_system_properties = NULL;
66 const char* Arguments::_gc_log_filename = NULL;
67 bool Arguments::_has_profile = false;
68 bool Arguments::_has_alloc_profile = false;
69 uintx Arguments::_min_heap_size = 0;
70 Arguments::Mode Arguments::_mode = _mixed;
71 bool Arguments::_java_compiler = false;
72 bool Arguments::_xdebug_mode = false;
73 const char* Arguments::_java_vendor_url_bug = DEFAULT_VENDOR_URL_BUG;
74 const char* Arguments::_sun_java_launcher = DEFAULT_JAVA_LAUNCHER;
75 int Arguments::_sun_java_launcher_pid = -1;
76 bool Arguments::_created_by_gamma_launcher = false;
78 // These parameters are reset in method parse_vm_init_args(JavaVMInitArgs*)
79 bool Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
80 bool Arguments::_UseOnStackReplacement = UseOnStackReplacement;
81 bool Arguments::_BackgroundCompilation = BackgroundCompilation;
82 bool Arguments::_ClipInlining = ClipInlining;
84 char* Arguments::SharedArchivePath = NULL;
86 AgentLibraryList Arguments::_libraryList;
87 AgentLibraryList Arguments::_agentList;
89 abort_hook_t Arguments::_abort_hook = NULL;
90 exit_hook_t Arguments::_exit_hook = NULL;
91 vfprintf_hook_t Arguments::_vfprintf_hook = NULL;
94 SystemProperty *Arguments::_java_ext_dirs = NULL;
95 SystemProperty *Arguments::_java_endorsed_dirs = NULL;
96 SystemProperty *Arguments::_sun_boot_library_path = NULL;
97 SystemProperty *Arguments::_java_library_path = NULL;
98 SystemProperty *Arguments::_java_home = NULL;
99 SystemProperty *Arguments::_java_class_path = NULL;
100 SystemProperty *Arguments::_sun_boot_class_path = NULL;
102 char* Arguments::_meta_index_path = NULL;
103 char* Arguments::_meta_index_dir = NULL;
105 static bool force_client_mode = false;
107 // Check if head of 'option' matches 'name', and sets 'tail' remaining part of option string
109 static bool match_option(const JavaVMOption *option, const char* name,
110 const char** tail) {
111 int len = (int)strlen(name);
112 if (strncmp(option->optionString, name, len) == 0) {
113 *tail = option->optionString + len;
114 return true;
115 } else {
116 return false;
117 }
118 }
120 static void logOption(const char* opt) {
121 if (PrintVMOptions) {
122 jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
123 }
124 }
126 // Process java launcher properties.
127 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
128 // See if sun.java.launcher or sun.java.launcher.pid is defined.
129 // Must do this before setting up other system properties,
130 // as some of them may depend on launcher type.
131 for (int index = 0; index < args->nOptions; index++) {
132 const JavaVMOption* option = args->options + index;
133 const char* tail;
135 if (match_option(option, "-Dsun.java.launcher=", &tail)) {
136 process_java_launcher_argument(tail, option->extraInfo);
137 continue;
138 }
139 if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
140 _sun_java_launcher_pid = atoi(tail);
141 continue;
142 }
143 }
144 }
146 // Initialize system properties key and value.
147 void Arguments::init_system_properties() {
149 PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
150 "Java Virtual Machine Specification", false));
151 PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(), false));
152 PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(), false));
153 PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(), true));
155 // following are JVMTI agent writeable properties.
156 // Properties values are set to NULL and they are
157 // os specific they are initialized in os::init_system_properties_values().
158 _java_ext_dirs = new SystemProperty("java.ext.dirs", NULL, true);
159 _java_endorsed_dirs = new SystemProperty("java.endorsed.dirs", NULL, true);
160 _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL, true);
161 _java_library_path = new SystemProperty("java.library.path", NULL, true);
162 _java_home = new SystemProperty("java.home", NULL, true);
163 _sun_boot_class_path = new SystemProperty("sun.boot.class.path", NULL, true);
165 _java_class_path = new SystemProperty("java.class.path", "", true);
167 // Add to System Property list.
168 PropertyList_add(&_system_properties, _java_ext_dirs);
169 PropertyList_add(&_system_properties, _java_endorsed_dirs);
170 PropertyList_add(&_system_properties, _sun_boot_library_path);
171 PropertyList_add(&_system_properties, _java_library_path);
172 PropertyList_add(&_system_properties, _java_home);
173 PropertyList_add(&_system_properties, _java_class_path);
174 PropertyList_add(&_system_properties, _sun_boot_class_path);
176 // Set OS specific system properties values
177 os::init_system_properties_values();
178 }
181 // Update/Initialize System properties after JDK version number is known
182 void Arguments::init_version_specific_system_properties() {
183 enum { bufsz = 16 };
184 char buffer[bufsz];
185 const char* spec_vendor = "Sun Microsystems Inc.";
186 uint32_t spec_version = 0;
188 if (JDK_Version::is_gte_jdk17x_version()) {
189 spec_vendor = "Oracle Corporation";
190 spec_version = JDK_Version::current().major_version();
191 }
192 jio_snprintf(buffer, bufsz, "1." UINT32_FORMAT, spec_version);
194 PropertyList_add(&_system_properties,
195 new SystemProperty("java.vm.specification.vendor", spec_vendor, false));
196 PropertyList_add(&_system_properties,
197 new SystemProperty("java.vm.specification.version", buffer, false));
198 PropertyList_add(&_system_properties,
199 new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(), false));
200 }
202 /**
203 * Provide a slightly more user-friendly way of eliminating -XX flags.
204 * When a flag is eliminated, it can be added to this list in order to
205 * continue accepting this flag on the command-line, while issuing a warning
206 * and ignoring the value. Once the JDK version reaches the 'accept_until'
207 * limit, we flatly refuse to admit the existence of the flag. This allows
208 * a flag to die correctly over JDK releases using HSX.
209 */
210 typedef struct {
211 const char* name;
212 JDK_Version obsoleted_in; // when the flag went away
213 JDK_Version accept_until; // which version to start denying the existence
214 } ObsoleteFlag;
216 static ObsoleteFlag obsolete_jvm_flags[] = {
217 { "UseTrainGC", JDK_Version::jdk(5), JDK_Version::jdk(7) },
218 { "UseSpecialLargeObjectHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
219 { "UseOversizedCarHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
220 { "TraceCarAllocation", JDK_Version::jdk(5), JDK_Version::jdk(7) },
221 { "PrintTrainGCProcessingStats", JDK_Version::jdk(5), JDK_Version::jdk(7) },
222 { "LogOfCarSpaceSize", JDK_Version::jdk(5), JDK_Version::jdk(7) },
223 { "OversizedCarThreshold", JDK_Version::jdk(5), JDK_Version::jdk(7) },
224 { "MinTickInterval", JDK_Version::jdk(5), JDK_Version::jdk(7) },
225 { "DefaultTickInterval", JDK_Version::jdk(5), JDK_Version::jdk(7) },
226 { "MaxTickInterval", JDK_Version::jdk(5), JDK_Version::jdk(7) },
227 { "DelayTickAdjustment", JDK_Version::jdk(5), JDK_Version::jdk(7) },
228 { "ProcessingToTenuringRatio", JDK_Version::jdk(5), JDK_Version::jdk(7) },
229 { "MinTrainLength", JDK_Version::jdk(5), JDK_Version::jdk(7) },
230 { "AppendRatio", JDK_Version::jdk_update(6,10), JDK_Version::jdk(7) },
231 { "DefaultMaxRAM", JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
232 { "DefaultInitialRAMFraction",
233 JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
234 { "UseDepthFirstScavengeOrder",
235 JDK_Version::jdk_update(6,22), JDK_Version::jdk(7) },
236 { "HandlePromotionFailure",
237 JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
238 { "MaxLiveObjectEvacuationRatio",
239 JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
240 { "ForceSharedSpaces", JDK_Version::jdk_update(6,25), JDK_Version::jdk(8) },
241 { "UseParallelOldGCCompacting",
242 JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
243 { "UseParallelDensePrefixUpdate",
244 JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
245 { "UseParallelOldGCDensePrefix",
246 JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
247 { "AllowTransitionalJSR292", JDK_Version::jdk(7), JDK_Version::jdk(8) },
248 { "UseCompressedStrings", JDK_Version::jdk(7), JDK_Version::jdk(8) },
249 #ifdef PRODUCT
250 { "DesiredMethodLimit",
251 JDK_Version::jdk_update(7, 2), JDK_Version::jdk(8) },
252 #endif // PRODUCT
253 { NULL, JDK_Version(0), JDK_Version(0) }
254 };
256 // Returns true if the flag is obsolete and fits into the range specified
257 // for being ignored. In the case that the flag is ignored, the 'version'
258 // value is filled in with the version number when the flag became
259 // obsolete so that that value can be displayed to the user.
260 bool Arguments::is_newly_obsolete(const char *s, JDK_Version* version) {
261 int i = 0;
262 assert(version != NULL, "Must provide a version buffer");
263 while (obsolete_jvm_flags[i].name != NULL) {
264 const ObsoleteFlag& flag_status = obsolete_jvm_flags[i];
265 // <flag>=xxx form
266 // [-|+]<flag> form
267 if ((strncmp(flag_status.name, s, strlen(flag_status.name)) == 0) ||
268 ((s[0] == '+' || s[0] == '-') &&
269 (strncmp(flag_status.name, &s[1], strlen(flag_status.name)) == 0))) {
270 if (JDK_Version::current().compare(flag_status.accept_until) == -1) {
271 *version = flag_status.obsoleted_in;
272 return true;
273 }
274 }
275 i++;
276 }
277 return false;
278 }
280 // Constructs the system class path (aka boot class path) from the following
281 // components, in order:
282 //
283 // prefix // from -Xbootclasspath/p:...
284 // endorsed // the expansion of -Djava.endorsed.dirs=...
285 // base // from os::get_system_properties() or -Xbootclasspath=
286 // suffix // from -Xbootclasspath/a:...
287 //
288 // java.endorsed.dirs is a list of directories; any jar or zip files in the
289 // directories are added to the sysclasspath just before the base.
290 //
291 // This could be AllStatic, but it isn't needed after argument processing is
292 // complete.
293 class SysClassPath: public StackObj {
294 public:
295 SysClassPath(const char* base);
296 ~SysClassPath();
298 inline void set_base(const char* base);
299 inline void add_prefix(const char* prefix);
300 inline void add_suffix_to_prefix(const char* suffix);
301 inline void add_suffix(const char* suffix);
302 inline void reset_path(const char* base);
304 // Expand the jar/zip files in each directory listed by the java.endorsed.dirs
305 // property. Must be called after all command-line arguments have been
306 // processed (in particular, -Djava.endorsed.dirs=...) and before calling
307 // combined_path().
308 void expand_endorsed();
310 inline const char* get_base() const { return _items[_scp_base]; }
311 inline const char* get_prefix() const { return _items[_scp_prefix]; }
312 inline const char* get_suffix() const { return _items[_scp_suffix]; }
313 inline const char* get_endorsed() const { return _items[_scp_endorsed]; }
315 // Combine all the components into a single c-heap-allocated string; caller
316 // must free the string if/when no longer needed.
317 char* combined_path();
319 private:
320 // Utility routines.
321 static char* add_to_path(const char* path, const char* str, bool prepend);
322 static char* add_jars_to_path(char* path, const char* directory);
324 inline void reset_item_at(int index);
326 // Array indices for the items that make up the sysclasspath. All except the
327 // base are allocated in the C heap and freed by this class.
328 enum {
329 _scp_prefix, // from -Xbootclasspath/p:...
330 _scp_endorsed, // the expansion of -Djava.endorsed.dirs=...
331 _scp_base, // the default sysclasspath
332 _scp_suffix, // from -Xbootclasspath/a:...
333 _scp_nitems // the number of items, must be last.
334 };
336 const char* _items[_scp_nitems];
337 DEBUG_ONLY(bool _expansion_done;)
338 };
340 SysClassPath::SysClassPath(const char* base) {
341 memset(_items, 0, sizeof(_items));
342 _items[_scp_base] = base;
343 DEBUG_ONLY(_expansion_done = false;)
344 }
346 SysClassPath::~SysClassPath() {
347 // Free everything except the base.
348 for (int i = 0; i < _scp_nitems; ++i) {
349 if (i != _scp_base) reset_item_at(i);
350 }
351 DEBUG_ONLY(_expansion_done = false;)
352 }
354 inline void SysClassPath::set_base(const char* base) {
355 _items[_scp_base] = base;
356 }
358 inline void SysClassPath::add_prefix(const char* prefix) {
359 _items[_scp_prefix] = add_to_path(_items[_scp_prefix], prefix, true);
360 }
362 inline void SysClassPath::add_suffix_to_prefix(const char* suffix) {
363 _items[_scp_prefix] = add_to_path(_items[_scp_prefix], suffix, false);
364 }
366 inline void SysClassPath::add_suffix(const char* suffix) {
367 _items[_scp_suffix] = add_to_path(_items[_scp_suffix], suffix, false);
368 }
370 inline void SysClassPath::reset_item_at(int index) {
371 assert(index < _scp_nitems && index != _scp_base, "just checking");
372 if (_items[index] != NULL) {
373 FREE_C_HEAP_ARRAY(char, _items[index]);
374 _items[index] = NULL;
375 }
376 }
378 inline void SysClassPath::reset_path(const char* base) {
379 // Clear the prefix and suffix.
380 reset_item_at(_scp_prefix);
381 reset_item_at(_scp_suffix);
382 set_base(base);
383 }
385 //------------------------------------------------------------------------------
387 void SysClassPath::expand_endorsed() {
388 assert(_items[_scp_endorsed] == NULL, "can only be called once.");
390 const char* path = Arguments::get_property("java.endorsed.dirs");
391 if (path == NULL) {
392 path = Arguments::get_endorsed_dir();
393 assert(path != NULL, "no default for java.endorsed.dirs");
394 }
396 char* expanded_path = NULL;
397 const char separator = *os::path_separator();
398 const char* const end = path + strlen(path);
399 while (path < end) {
400 const char* tmp_end = strchr(path, separator);
401 if (tmp_end == NULL) {
402 expanded_path = add_jars_to_path(expanded_path, path);
403 path = end;
404 } else {
405 char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1);
406 memcpy(dirpath, path, tmp_end - path);
407 dirpath[tmp_end - path] = '\0';
408 expanded_path = add_jars_to_path(expanded_path, dirpath);
409 FREE_C_HEAP_ARRAY(char, dirpath);
410 path = tmp_end + 1;
411 }
412 }
413 _items[_scp_endorsed] = expanded_path;
414 DEBUG_ONLY(_expansion_done = true;)
415 }
417 // Combine the bootclasspath elements, some of which may be null, into a single
418 // c-heap-allocated string.
419 char* SysClassPath::combined_path() {
420 assert(_items[_scp_base] != NULL, "empty default sysclasspath");
421 assert(_expansion_done, "must call expand_endorsed() first.");
423 size_t lengths[_scp_nitems];
424 size_t total_len = 0;
426 const char separator = *os::path_separator();
428 // Get the lengths.
429 int i;
430 for (i = 0; i < _scp_nitems; ++i) {
431 if (_items[i] != NULL) {
432 lengths[i] = strlen(_items[i]);
433 // Include space for the separator char (or a NULL for the last item).
434 total_len += lengths[i] + 1;
435 }
436 }
437 assert(total_len > 0, "empty sysclasspath not allowed");
439 // Copy the _items to a single string.
440 char* cp = NEW_C_HEAP_ARRAY(char, total_len);
441 char* cp_tmp = cp;
442 for (i = 0; i < _scp_nitems; ++i) {
443 if (_items[i] != NULL) {
444 memcpy(cp_tmp, _items[i], lengths[i]);
445 cp_tmp += lengths[i];
446 *cp_tmp++ = separator;
447 }
448 }
449 *--cp_tmp = '\0'; // Replace the extra separator.
450 return cp;
451 }
453 // Note: path must be c-heap-allocated (or NULL); it is freed if non-null.
454 char*
455 SysClassPath::add_to_path(const char* path, const char* str, bool prepend) {
456 char *cp;
458 assert(str != NULL, "just checking");
459 if (path == NULL) {
460 size_t len = strlen(str) + 1;
461 cp = NEW_C_HEAP_ARRAY(char, len);
462 memcpy(cp, str, len); // copy the trailing null
463 } else {
464 const char separator = *os::path_separator();
465 size_t old_len = strlen(path);
466 size_t str_len = strlen(str);
467 size_t len = old_len + str_len + 2;
469 if (prepend) {
470 cp = NEW_C_HEAP_ARRAY(char, len);
471 char* cp_tmp = cp;
472 memcpy(cp_tmp, str, str_len);
473 cp_tmp += str_len;
474 *cp_tmp = separator;
475 memcpy(++cp_tmp, path, old_len + 1); // copy the trailing null
476 FREE_C_HEAP_ARRAY(char, path);
477 } else {
478 cp = REALLOC_C_HEAP_ARRAY(char, path, len);
479 char* cp_tmp = cp + old_len;
480 *cp_tmp = separator;
481 memcpy(++cp_tmp, str, str_len + 1); // copy the trailing null
482 }
483 }
484 return cp;
485 }
487 // Scan the directory and append any jar or zip files found to path.
488 // Note: path must be c-heap-allocated (or NULL); it is freed if non-null.
489 char* SysClassPath::add_jars_to_path(char* path, const char* directory) {
490 DIR* dir = os::opendir(directory);
491 if (dir == NULL) return path;
493 char dir_sep[2] = { '\0', '\0' };
494 size_t directory_len = strlen(directory);
495 const char fileSep = *os::file_separator();
496 if (directory[directory_len - 1] != fileSep) dir_sep[0] = fileSep;
498 /* Scan the directory for jars/zips, appending them to path. */
499 struct dirent *entry;
500 char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory));
501 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
502 const char* name = entry->d_name;
503 const char* ext = name + strlen(name) - 4;
504 bool isJarOrZip = ext > name &&
505 (os::file_name_strcmp(ext, ".jar") == 0 ||
506 os::file_name_strcmp(ext, ".zip") == 0);
507 if (isJarOrZip) {
508 char* jarpath = NEW_C_HEAP_ARRAY(char, directory_len + 2 + strlen(name));
509 sprintf(jarpath, "%s%s%s", directory, dir_sep, name);
510 path = add_to_path(path, jarpath, false);
511 FREE_C_HEAP_ARRAY(char, jarpath);
512 }
513 }
514 FREE_C_HEAP_ARRAY(char, dbuf);
515 os::closedir(dir);
516 return path;
517 }
519 // Parses a memory size specification string.
520 static bool atomull(const char *s, julong* result) {
521 julong n = 0;
522 int args_read = sscanf(s, os::julong_format_specifier(), &n);
523 if (args_read != 1) {
524 return false;
525 }
526 while (*s != '\0' && isdigit(*s)) {
527 s++;
528 }
529 // 4705540: illegal if more characters are found after the first non-digit
530 if (strlen(s) > 1) {
531 return false;
532 }
533 switch (*s) {
534 case 'T': case 't':
535 *result = n * G * K;
536 // Check for overflow.
537 if (*result/((julong)G * K) != n) return false;
538 return true;
539 case 'G': case 'g':
540 *result = n * G;
541 if (*result/G != n) return false;
542 return true;
543 case 'M': case 'm':
544 *result = n * M;
545 if (*result/M != n) return false;
546 return true;
547 case 'K': case 'k':
548 *result = n * K;
549 if (*result/K != n) return false;
550 return true;
551 case '\0':
552 *result = n;
553 return true;
554 default:
555 return false;
556 }
557 }
559 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size) {
560 if (size < min_size) return arg_too_small;
561 // Check that size will fit in a size_t (only relevant on 32-bit)
562 if (size > max_uintx) return arg_too_big;
563 return arg_in_range;
564 }
566 // Describe an argument out of range error
567 void Arguments::describe_range_error(ArgsRange errcode) {
568 switch(errcode) {
569 case arg_too_big:
570 jio_fprintf(defaultStream::error_stream(),
571 "The specified size exceeds the maximum "
572 "representable size.\n");
573 break;
574 case arg_too_small:
575 case arg_unreadable:
576 case arg_in_range:
577 // do nothing for now
578 break;
579 default:
580 ShouldNotReachHere();
581 }
582 }
584 static bool set_bool_flag(char* name, bool value, FlagValueOrigin origin) {
585 return CommandLineFlags::boolAtPut(name, &value, origin);
586 }
588 static bool set_fp_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
589 double v;
590 if (sscanf(value, "%lf", &v) != 1) {
591 return false;
592 }
594 if (CommandLineFlags::doubleAtPut(name, &v, origin)) {
595 return true;
596 }
597 return false;
598 }
600 static bool set_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
601 julong v;
602 intx intx_v;
603 bool is_neg = false;
604 // Check the sign first since atomull() parses only unsigned values.
605 if (*value == '-') {
606 if (!CommandLineFlags::intxAt(name, &intx_v)) {
607 return false;
608 }
609 value++;
610 is_neg = true;
611 }
612 if (!atomull(value, &v)) {
613 return false;
614 }
615 intx_v = (intx) v;
616 if (is_neg) {
617 intx_v = -intx_v;
618 }
619 if (CommandLineFlags::intxAtPut(name, &intx_v, origin)) {
620 return true;
621 }
622 uintx uintx_v = (uintx) v;
623 if (!is_neg && CommandLineFlags::uintxAtPut(name, &uintx_v, origin)) {
624 return true;
625 }
626 uint64_t uint64_t_v = (uint64_t) v;
627 if (!is_neg && CommandLineFlags::uint64_tAtPut(name, &uint64_t_v, origin)) {
628 return true;
629 }
630 return false;
631 }
633 static bool set_string_flag(char* name, const char* value, FlagValueOrigin origin) {
634 if (!CommandLineFlags::ccstrAtPut(name, &value, origin)) return false;
635 // Contract: CommandLineFlags always returns a pointer that needs freeing.
636 FREE_C_HEAP_ARRAY(char, value);
637 return true;
638 }
640 static bool append_to_string_flag(char* name, const char* new_value, FlagValueOrigin origin) {
641 const char* old_value = "";
642 if (!CommandLineFlags::ccstrAt(name, &old_value)) return false;
643 size_t old_len = old_value != NULL ? strlen(old_value) : 0;
644 size_t new_len = strlen(new_value);
645 const char* value;
646 char* free_this_too = NULL;
647 if (old_len == 0) {
648 value = new_value;
649 } else if (new_len == 0) {
650 value = old_value;
651 } else {
652 char* buf = NEW_C_HEAP_ARRAY(char, old_len + 1 + new_len + 1);
653 // each new setting adds another LINE to the switch:
654 sprintf(buf, "%s\n%s", old_value, new_value);
655 value = buf;
656 free_this_too = buf;
657 }
658 (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
659 // CommandLineFlags always returns a pointer that needs freeing.
660 FREE_C_HEAP_ARRAY(char, value);
661 if (free_this_too != NULL) {
662 // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
663 FREE_C_HEAP_ARRAY(char, free_this_too);
664 }
665 return true;
666 }
668 bool Arguments::parse_argument(const char* arg, FlagValueOrigin origin) {
670 // range of acceptable characters spelled out for portability reasons
671 #define NAME_RANGE "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
672 #define BUFLEN 255
673 char name[BUFLEN+1];
674 char dummy;
676 if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
677 return set_bool_flag(name, false, origin);
678 }
679 if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
680 return set_bool_flag(name, true, origin);
681 }
683 char punct;
684 if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
685 const char* value = strchr(arg, '=') + 1;
686 Flag* flag = Flag::find_flag(name, strlen(name));
687 if (flag != NULL && flag->is_ccstr()) {
688 if (flag->ccstr_accumulates()) {
689 return append_to_string_flag(name, value, origin);
690 } else {
691 if (value[0] == '\0') {
692 value = NULL;
693 }
694 return set_string_flag(name, value, origin);
695 }
696 }
697 }
699 if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
700 const char* value = strchr(arg, '=') + 1;
701 // -XX:Foo:=xxx will reset the string flag to the given value.
702 if (value[0] == '\0') {
703 value = NULL;
704 }
705 return set_string_flag(name, value, origin);
706 }
708 #define SIGNED_FP_NUMBER_RANGE "[-0123456789.]"
709 #define SIGNED_NUMBER_RANGE "[-0123456789]"
710 #define NUMBER_RANGE "[0123456789]"
711 char value[BUFLEN + 1];
712 char value2[BUFLEN + 1];
713 if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
714 // Looks like a floating-point number -- try again with more lenient format string
715 if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
716 return set_fp_numeric_flag(name, value, origin);
717 }
718 }
720 #define VALUE_RANGE "[-kmgtKMGT0123456789]"
721 if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
722 return set_numeric_flag(name, value, origin);
723 }
725 return false;
726 }
728 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
729 assert(bldarray != NULL, "illegal argument");
731 if (arg == NULL) {
732 return;
733 }
735 int index = *count;
737 // expand the array and add arg to the last element
738 (*count)++;
739 if (*bldarray == NULL) {
740 *bldarray = NEW_C_HEAP_ARRAY(char*, *count);
741 } else {
742 *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, *count);
743 }
744 (*bldarray)[index] = strdup(arg);
745 }
747 void Arguments::build_jvm_args(const char* arg) {
748 add_string(&_jvm_args_array, &_num_jvm_args, arg);
749 }
751 void Arguments::build_jvm_flags(const char* arg) {
752 add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
753 }
755 // utility function to return a string that concatenates all
756 // strings in a given char** array
757 const char* Arguments::build_resource_string(char** args, int count) {
758 if (args == NULL || count == 0) {
759 return NULL;
760 }
761 size_t length = strlen(args[0]) + 1; // add 1 for the null terminator
762 for (int i = 1; i < count; i++) {
763 length += strlen(args[i]) + 1; // add 1 for a space
764 }
765 char* s = NEW_RESOURCE_ARRAY(char, length);
766 strcpy(s, args[0]);
767 for (int j = 1; j < count; j++) {
768 strcat(s, " ");
769 strcat(s, args[j]);
770 }
771 return (const char*) s;
772 }
774 void Arguments::print_on(outputStream* st) {
775 st->print_cr("VM Arguments:");
776 if (num_jvm_flags() > 0) {
777 st->print("jvm_flags: "); print_jvm_flags_on(st);
778 }
779 if (num_jvm_args() > 0) {
780 st->print("jvm_args: "); print_jvm_args_on(st);
781 }
782 st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
783 st->print_cr("Launcher Type: %s", _sun_java_launcher);
784 }
786 void Arguments::print_jvm_flags_on(outputStream* st) {
787 if (_num_jvm_flags > 0) {
788 for (int i=0; i < _num_jvm_flags; i++) {
789 st->print("%s ", _jvm_flags_array[i]);
790 }
791 st->print_cr("");
792 }
793 }
795 void Arguments::print_jvm_args_on(outputStream* st) {
796 if (_num_jvm_args > 0) {
797 for (int i=0; i < _num_jvm_args; i++) {
798 st->print("%s ", _jvm_args_array[i]);
799 }
800 st->print_cr("");
801 }
802 }
804 bool Arguments::process_argument(const char* arg,
805 jboolean ignore_unrecognized, FlagValueOrigin origin) {
807 JDK_Version since = JDK_Version();
809 if (parse_argument(arg, origin) || ignore_unrecognized) {
810 return true;
811 }
813 const char * const argname = *arg == '+' || *arg == '-' ? arg + 1 : arg;
814 if (is_newly_obsolete(arg, &since)) {
815 char version[256];
816 since.to_string(version, sizeof(version));
817 warning("ignoring option %s; support was removed in %s", argname, version);
818 return true;
819 }
821 jio_fprintf(defaultStream::error_stream(),
822 "Unrecognized VM option '%s'\n", argname);
823 // allow for commandline "commenting out" options like -XX:#+Verbose
824 return arg[0] == '#';
825 }
827 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
828 FILE* stream = fopen(file_name, "rb");
829 if (stream == NULL) {
830 if (should_exist) {
831 jio_fprintf(defaultStream::error_stream(),
832 "Could not open settings file %s\n", file_name);
833 return false;
834 } else {
835 return true;
836 }
837 }
839 char token[1024];
840 int pos = 0;
842 bool in_white_space = true;
843 bool in_comment = false;
844 bool in_quote = false;
845 char quote_c = 0;
846 bool result = true;
848 int c = getc(stream);
849 while(c != EOF) {
850 if (in_white_space) {
851 if (in_comment) {
852 if (c == '\n') in_comment = false;
853 } else {
854 if (c == '#') in_comment = true;
855 else if (!isspace(c)) {
856 in_white_space = false;
857 token[pos++] = c;
858 }
859 }
860 } else {
861 if (c == '\n' || (!in_quote && isspace(c))) {
862 // token ends at newline, or at unquoted whitespace
863 // this allows a way to include spaces in string-valued options
864 token[pos] = '\0';
865 logOption(token);
866 result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
867 build_jvm_flags(token);
868 pos = 0;
869 in_white_space = true;
870 in_quote = false;
871 } else if (!in_quote && (c == '\'' || c == '"')) {
872 in_quote = true;
873 quote_c = c;
874 } else if (in_quote && (c == quote_c)) {
875 in_quote = false;
876 } else {
877 token[pos++] = c;
878 }
879 }
880 c = getc(stream);
881 }
882 if (pos > 0) {
883 token[pos] = '\0';
884 result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
885 build_jvm_flags(token);
886 }
887 fclose(stream);
888 return result;
889 }
891 //=============================================================================================================
892 // Parsing of properties (-D)
894 const char* Arguments::get_property(const char* key) {
895 return PropertyList_get_value(system_properties(), key);
896 }
898 bool Arguments::add_property(const char* prop) {
899 const char* eq = strchr(prop, '=');
900 char* key;
901 // ns must be static--its address may be stored in a SystemProperty object.
902 const static char ns[1] = {0};
903 char* value = (char *)ns;
905 size_t key_len = (eq == NULL) ? strlen(prop) : (eq - prop);
906 key = AllocateHeap(key_len + 1, "add_property");
907 strncpy(key, prop, key_len);
908 key[key_len] = '\0';
910 if (eq != NULL) {
911 size_t value_len = strlen(prop) - key_len - 1;
912 value = AllocateHeap(value_len + 1, "add_property");
913 strncpy(value, &prop[key_len + 1], value_len + 1);
914 }
916 if (strcmp(key, "java.compiler") == 0) {
917 process_java_compiler_argument(value);
918 FreeHeap(key);
919 if (eq != NULL) {
920 FreeHeap(value);
921 }
922 return true;
923 } else if (strcmp(key, "sun.java.command") == 0) {
924 _java_command = value;
926 // Record value in Arguments, but let it get passed to Java.
927 } else if (strcmp(key, "sun.java.launcher.pid") == 0) {
928 // launcher.pid property is private and is processed
929 // in process_sun_java_launcher_properties();
930 // the sun.java.launcher property is passed on to the java application
931 FreeHeap(key);
932 if (eq != NULL) {
933 FreeHeap(value);
934 }
935 return true;
936 } else if (strcmp(key, "java.vendor.url.bug") == 0) {
937 // save it in _java_vendor_url_bug, so JVM fatal error handler can access
938 // its value without going through the property list or making a Java call.
939 _java_vendor_url_bug = value;
940 } else if (strcmp(key, "sun.boot.library.path") == 0) {
941 PropertyList_unique_add(&_system_properties, key, value, true);
942 return true;
943 }
944 // Create new property and add at the end of the list
945 PropertyList_unique_add(&_system_properties, key, value);
946 return true;
947 }
949 //===========================================================================================================
950 // Setting int/mixed/comp mode flags
952 void Arguments::set_mode_flags(Mode mode) {
953 // Set up default values for all flags.
954 // If you add a flag to any of the branches below,
955 // add a default value for it here.
956 set_java_compiler(false);
957 _mode = mode;
959 // Ensure Agent_OnLoad has the correct initial values.
960 // This may not be the final mode; mode may change later in onload phase.
961 PropertyList_unique_add(&_system_properties, "java.vm.info",
962 (char*)VM_Version::vm_info_string(), false);
964 UseInterpreter = true;
965 UseCompiler = true;
966 UseLoopCounter = true;
968 #ifndef ZERO
969 // Turn these off for mixed and comp. Leave them on for Zero.
970 if (FLAG_IS_DEFAULT(UseFastAccessorMethods)) {
971 UseFastAccessorMethods = (mode == _int);
972 }
973 if (FLAG_IS_DEFAULT(UseFastEmptyMethods)) {
974 UseFastEmptyMethods = (mode == _int);
975 }
976 #endif
978 // Default values may be platform/compiler dependent -
979 // use the saved values
980 ClipInlining = Arguments::_ClipInlining;
981 AlwaysCompileLoopMethods = Arguments::_AlwaysCompileLoopMethods;
982 UseOnStackReplacement = Arguments::_UseOnStackReplacement;
983 BackgroundCompilation = Arguments::_BackgroundCompilation;
985 // Change from defaults based on mode
986 switch (mode) {
987 default:
988 ShouldNotReachHere();
989 break;
990 case _int:
991 UseCompiler = false;
992 UseLoopCounter = false;
993 AlwaysCompileLoopMethods = false;
994 UseOnStackReplacement = false;
995 break;
996 case _mixed:
997 // same as default
998 break;
999 case _comp:
1000 UseInterpreter = false;
1001 BackgroundCompilation = false;
1002 ClipInlining = false;
1003 // Be much more aggressive in tiered mode with -Xcomp and exercise C2 more.
1004 // We will first compile a level 3 version (C1 with full profiling), then do one invocation of it and
1005 // compile a level 4 (C2) and then continue executing it.
1006 if (TieredCompilation) {
1007 Tier3InvokeNotifyFreqLog = 0;
1008 Tier4InvocationThreshold = 0;
1009 }
1010 break;
1011 }
1012 }
1014 // Conflict: required to use shared spaces (-Xshare:on), but
1015 // incompatible command line options were chosen.
1017 static void no_shared_spaces() {
1018 if (RequireSharedSpaces) {
1019 jio_fprintf(defaultStream::error_stream(),
1020 "Class data sharing is inconsistent with other specified options.\n");
1021 vm_exit_during_initialization("Unable to use shared archive.", NULL);
1022 } else {
1023 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1024 }
1025 }
1027 void Arguments::set_tiered_flags() {
1028 // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
1029 if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
1030 FLAG_SET_DEFAULT(CompilationPolicyChoice, 3);
1031 }
1032 if (CompilationPolicyChoice < 2) {
1033 vm_exit_during_initialization(
1034 "Incompatible compilation policy selected", NULL);
1035 }
1036 // Increase the code cache size - tiered compiles a lot more.
1037 if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1038 FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 2);
1039 }
1040 }
1042 #ifndef KERNEL
1043 static void disable_adaptive_size_policy(const char* collector_name) {
1044 if (UseAdaptiveSizePolicy) {
1045 if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1046 warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1047 collector_name);
1048 }
1049 FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1050 }
1051 }
1053 // If the user has chosen ParallelGCThreads > 0, we set UseParNewGC
1054 // if it's not explictly set or unset. If the user has chosen
1055 // UseParNewGC and not explicitly set ParallelGCThreads we
1056 // set it, unless this is a single cpu machine.
1057 void Arguments::set_parnew_gc_flags() {
1058 assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1059 "control point invariant");
1060 assert(UseParNewGC, "Error");
1062 // Turn off AdaptiveSizePolicy for parnew until it is complete.
1063 disable_adaptive_size_policy("UseParNewGC");
1065 if (ParallelGCThreads == 0) {
1066 FLAG_SET_DEFAULT(ParallelGCThreads,
1067 Abstract_VM_Version::parallel_worker_threads());
1068 if (ParallelGCThreads == 1) {
1069 FLAG_SET_DEFAULT(UseParNewGC, false);
1070 FLAG_SET_DEFAULT(ParallelGCThreads, 0);
1071 }
1072 }
1073 if (UseParNewGC) {
1074 // CDS doesn't work with ParNew yet
1075 no_shared_spaces();
1077 // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1078 // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1079 // we set them to 1024 and 1024.
1080 // See CR 6362902.
1081 if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1082 FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1083 }
1084 if (FLAG_IS_DEFAULT(OldPLABSize)) {
1085 FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1086 }
1088 // AlwaysTenure flag should make ParNew promote all at first collection.
1089 // See CR 6362902.
1090 if (AlwaysTenure) {
1091 FLAG_SET_CMDLINE(intx, MaxTenuringThreshold, 0);
1092 }
1093 // When using compressed oops, we use local overflow stacks,
1094 // rather than using a global overflow list chained through
1095 // the klass word of the object's pre-image.
1096 if (UseCompressedOops && !ParGCUseLocalOverflow) {
1097 if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
1098 warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
1099 }
1100 FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
1101 }
1102 assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
1103 }
1104 }
1106 // Adjust some sizes to suit CMS and/or ParNew needs; these work well on
1107 // sparc/solaris for certain applications, but would gain from
1108 // further optimization and tuning efforts, and would almost
1109 // certainly gain from analysis of platform and environment.
1110 void Arguments::set_cms_and_parnew_gc_flags() {
1111 assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
1112 assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1114 // If we are using CMS, we prefer to UseParNewGC,
1115 // unless explicitly forbidden.
1116 if (FLAG_IS_DEFAULT(UseParNewGC)) {
1117 FLAG_SET_ERGO(bool, UseParNewGC, true);
1118 }
1120 // Turn off AdaptiveSizePolicy for CMS until it is complete.
1121 disable_adaptive_size_policy("UseConcMarkSweepGC");
1123 // In either case, adjust ParallelGCThreads and/or UseParNewGC
1124 // as needed.
1125 if (UseParNewGC) {
1126 set_parnew_gc_flags();
1127 }
1129 // MaxHeapSize is aligned down in collectorPolicy
1130 size_t max_heap = align_size_down(MaxHeapSize,
1131 CardTableRS::ct_max_alignment_constraint());
1133 // Now make adjustments for CMS
1134 intx tenuring_default = (intx)6;
1135 size_t young_gen_per_worker = CMSYoungGenPerWorker;
1137 // Preferred young gen size for "short" pauses:
1138 // upper bound depends on # of threads and NewRatio.
1139 const uintx parallel_gc_threads =
1140 (ParallelGCThreads == 0 ? 1 : ParallelGCThreads);
1141 const size_t preferred_max_new_size_unaligned =
1142 MIN2(max_heap/(NewRatio+1), ScaleForWordSize(young_gen_per_worker * parallel_gc_threads));
1143 size_t preferred_max_new_size =
1144 align_size_up(preferred_max_new_size_unaligned, os::vm_page_size());
1146 // Unless explicitly requested otherwise, size young gen
1147 // for "short" pauses ~ CMSYoungGenPerWorker*ParallelGCThreads
1149 // If either MaxNewSize or NewRatio is set on the command line,
1150 // assume the user is trying to set the size of the young gen.
1151 if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {
1153 // Set MaxNewSize to our calculated preferred_max_new_size unless
1154 // NewSize was set on the command line and it is larger than
1155 // preferred_max_new_size.
1156 if (!FLAG_IS_DEFAULT(NewSize)) { // NewSize explicitly set at command-line
1157 FLAG_SET_ERGO(uintx, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
1158 } else {
1159 FLAG_SET_ERGO(uintx, MaxNewSize, preferred_max_new_size);
1160 }
1161 if (PrintGCDetails && Verbose) {
1162 // Too early to use gclog_or_tty
1163 tty->print_cr("CMS ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
1164 }
1166 // Code along this path potentially sets NewSize and OldSize
1168 assert(max_heap >= InitialHeapSize, "Error");
1169 assert(max_heap >= NewSize, "Error");
1171 if (PrintGCDetails && Verbose) {
1172 // Too early to use gclog_or_tty
1173 tty->print_cr("CMS set min_heap_size: " SIZE_FORMAT
1174 " initial_heap_size: " SIZE_FORMAT
1175 " max_heap: " SIZE_FORMAT,
1176 min_heap_size(), InitialHeapSize, max_heap);
1177 }
1178 size_t min_new = preferred_max_new_size;
1179 if (FLAG_IS_CMDLINE(NewSize)) {
1180 min_new = NewSize;
1181 }
1182 if (max_heap > min_new && min_heap_size() > min_new) {
1183 // Unless explicitly requested otherwise, make young gen
1184 // at least min_new, and at most preferred_max_new_size.
1185 if (FLAG_IS_DEFAULT(NewSize)) {
1186 FLAG_SET_ERGO(uintx, NewSize, MAX2(NewSize, min_new));
1187 FLAG_SET_ERGO(uintx, NewSize, MIN2(preferred_max_new_size, NewSize));
1188 if (PrintGCDetails && Verbose) {
1189 // Too early to use gclog_or_tty
1190 tty->print_cr("CMS ergo set NewSize: " SIZE_FORMAT, NewSize);
1191 }
1192 }
1193 // Unless explicitly requested otherwise, size old gen
1194 // so it's NewRatio x of NewSize.
1195 if (FLAG_IS_DEFAULT(OldSize)) {
1196 if (max_heap > NewSize) {
1197 FLAG_SET_ERGO(uintx, OldSize, MIN2(NewRatio*NewSize, max_heap - NewSize));
1198 if (PrintGCDetails && Verbose) {
1199 // Too early to use gclog_or_tty
1200 tty->print_cr("CMS ergo set OldSize: " SIZE_FORMAT, OldSize);
1201 }
1202 }
1203 }
1204 }
1205 }
1206 // Unless explicitly requested otherwise, definitely
1207 // promote all objects surviving "tenuring_default" scavenges.
1208 if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
1209 FLAG_IS_DEFAULT(SurvivorRatio)) {
1210 FLAG_SET_ERGO(intx, MaxTenuringThreshold, tenuring_default);
1211 }
1212 // If we decided above (or user explicitly requested)
1213 // `promote all' (via MaxTenuringThreshold := 0),
1214 // prefer minuscule survivor spaces so as not to waste
1215 // space for (non-existent) survivors
1216 if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
1217 FLAG_SET_ERGO(intx, SurvivorRatio, MAX2((intx)1024, SurvivorRatio));
1218 }
1219 // If OldPLABSize is set and CMSParPromoteBlocksToClaim is not,
1220 // set CMSParPromoteBlocksToClaim equal to OldPLABSize.
1221 // This is done in order to make ParNew+CMS configuration to work
1222 // with YoungPLABSize and OldPLABSize options.
1223 // See CR 6362902.
1224 if (!FLAG_IS_DEFAULT(OldPLABSize)) {
1225 if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1226 // OldPLABSize is not the default value but CMSParPromoteBlocksToClaim
1227 // is. In this situtation let CMSParPromoteBlocksToClaim follow
1228 // the value (either from the command line or ergonomics) of
1229 // OldPLABSize. Following OldPLABSize is an ergonomics decision.
1230 FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, OldPLABSize);
1231 } else {
1232 // OldPLABSize and CMSParPromoteBlocksToClaim are both set.
1233 // CMSParPromoteBlocksToClaim is a collector-specific flag, so
1234 // we'll let it to take precedence.
1235 jio_fprintf(defaultStream::error_stream(),
1236 "Both OldPLABSize and CMSParPromoteBlocksToClaim"
1237 " options are specified for the CMS collector."
1238 " CMSParPromoteBlocksToClaim will take precedence.\n");
1239 }
1240 }
1241 if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
1242 // OldPLAB sizing manually turned off: Use a larger default setting,
1243 // unless it was manually specified. This is because a too-low value
1244 // will slow down scavenges.
1245 if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1246 FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, 50); // default value before 6631166
1247 }
1248 }
1249 // Overwrite OldPLABSize which is the variable we will internally use everywhere.
1250 FLAG_SET_ERGO(uintx, OldPLABSize, CMSParPromoteBlocksToClaim);
1251 // If either of the static initialization defaults have changed, note this
1252 // modification.
1253 if (!FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
1254 CFLS_LAB::modify_initialization(OldPLABSize, OldPLABWeight);
1255 }
1256 if (PrintGCDetails && Verbose) {
1257 tty->print_cr("MarkStackSize: %uk MarkStackSizeMax: %uk",
1258 MarkStackSize / K, MarkStackSizeMax / K);
1259 tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1260 }
1261 }
1262 #endif // KERNEL
1264 void set_object_alignment() {
1265 // Object alignment.
1266 assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1267 MinObjAlignmentInBytes = ObjectAlignmentInBytes;
1268 assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1269 MinObjAlignment = MinObjAlignmentInBytes / HeapWordSize;
1270 assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1271 MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1273 LogMinObjAlignmentInBytes = exact_log2(ObjectAlignmentInBytes);
1274 LogMinObjAlignment = LogMinObjAlignmentInBytes - LogHeapWordSize;
1276 // Oop encoding heap max
1277 OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1279 #ifndef KERNEL
1280 // Set CMS global values
1281 CompactibleFreeListSpace::set_cms_values();
1282 #endif // KERNEL
1283 }
1285 bool verify_object_alignment() {
1286 // Object alignment.
1287 if (!is_power_of_2(ObjectAlignmentInBytes)) {
1288 jio_fprintf(defaultStream::error_stream(),
1289 "error: ObjectAlignmentInBytes=%d must be power of 2\n",
1290 (int)ObjectAlignmentInBytes);
1291 return false;
1292 }
1293 if ((int)ObjectAlignmentInBytes < BytesPerLong) {
1294 jio_fprintf(defaultStream::error_stream(),
1295 "error: ObjectAlignmentInBytes=%d must be greater or equal %d\n",
1296 (int)ObjectAlignmentInBytes, BytesPerLong);
1297 return false;
1298 }
1299 // It does not make sense to have big object alignment
1300 // since a space lost due to alignment will be greater
1301 // then a saved space from compressed oops.
1302 if ((int)ObjectAlignmentInBytes > 256) {
1303 jio_fprintf(defaultStream::error_stream(),
1304 "error: ObjectAlignmentInBytes=%d must not be greater then 256\n",
1305 (int)ObjectAlignmentInBytes);
1306 return false;
1307 }
1308 // In case page size is very small.
1309 if ((int)ObjectAlignmentInBytes >= os::vm_page_size()) {
1310 jio_fprintf(defaultStream::error_stream(),
1311 "error: ObjectAlignmentInBytes=%d must be less then page size %d\n",
1312 (int)ObjectAlignmentInBytes, os::vm_page_size());
1313 return false;
1314 }
1315 return true;
1316 }
1318 inline uintx max_heap_for_compressed_oops() {
1319 // Avoid sign flip.
1320 if (OopEncodingHeapMax < MaxPermSize + os::vm_page_size()) {
1321 return 0;
1322 }
1323 LP64_ONLY(return OopEncodingHeapMax - MaxPermSize - os::vm_page_size());
1324 NOT_LP64(ShouldNotReachHere(); return 0);
1325 }
1327 bool Arguments::should_auto_select_low_pause_collector() {
1328 if (UseAutoGCSelectPolicy &&
1329 !FLAG_IS_DEFAULT(MaxGCPauseMillis) &&
1330 (MaxGCPauseMillis <= AutoGCSelectPauseMillis)) {
1331 if (PrintGCDetails) {
1332 // Cannot use gclog_or_tty yet.
1333 tty->print_cr("Automatic selection of the low pause collector"
1334 " based on pause goal of %d (ms)", MaxGCPauseMillis);
1335 }
1336 return true;
1337 }
1338 return false;
1339 }
1341 void Arguments::set_ergonomics_flags() {
1342 // Parallel GC is not compatible with sharing. If one specifies
1343 // that they want sharing explicitly, do not set ergonomics flags.
1344 if (DumpSharedSpaces || RequireSharedSpaces) {
1345 return;
1346 }
1348 if (os::is_server_class_machine() && !force_client_mode ) {
1349 // If no other collector is requested explicitly,
1350 // let the VM select the collector based on
1351 // machine class and automatic selection policy.
1352 if (!UseSerialGC &&
1353 !UseConcMarkSweepGC &&
1354 !UseG1GC &&
1355 !UseParNewGC &&
1356 !DumpSharedSpaces &&
1357 FLAG_IS_DEFAULT(UseParallelGC)) {
1358 if (should_auto_select_low_pause_collector()) {
1359 FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
1360 } else {
1361 FLAG_SET_ERGO(bool, UseParallelGC, true);
1362 }
1363 no_shared_spaces();
1364 }
1365 }
1367 #ifndef ZERO
1368 #ifdef _LP64
1369 // Check that UseCompressedOops can be set with the max heap size allocated
1370 // by ergonomics.
1371 if (MaxHeapSize <= max_heap_for_compressed_oops()) {
1372 #if !defined(COMPILER1) || defined(TIERED)
1373 // disable UseCompressedOops by default on MacOS X until 7118647 is fixed
1374 #ifndef __APPLE__
1375 if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1376 FLAG_SET_ERGO(bool, UseCompressedOops, true);
1377 }
1378 #endif // !__APPLE__
1379 #endif
1380 #ifdef _WIN64
1381 if (UseLargePages && UseCompressedOops) {
1382 // Cannot allocate guard pages for implicit checks in indexed addressing
1383 // mode, when large pages are specified on windows.
1384 // This flag could be switched ON if narrow oop base address is set to 0,
1385 // see code in Universe::initialize_heap().
1386 Universe::set_narrow_oop_use_implicit_null_checks(false);
1387 }
1388 #endif // _WIN64
1389 } else {
1390 if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1391 warning("Max heap size too large for Compressed Oops");
1392 FLAG_SET_DEFAULT(UseCompressedOops, false);
1393 }
1394 }
1395 // Also checks that certain machines are slower with compressed oops
1396 // in vm_version initialization code.
1397 #endif // _LP64
1398 #endif // !ZERO
1399 }
1401 void Arguments::set_parallel_gc_flags() {
1402 assert(UseParallelGC || UseParallelOldGC, "Error");
1403 // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
1404 if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
1405 FLAG_SET_DEFAULT(UseParallelOldGC, true);
1406 }
1407 FLAG_SET_DEFAULT(UseParallelGC, true);
1409 // If no heap maximum was requested explicitly, use some reasonable fraction
1410 // of the physical memory, up to a maximum of 1GB.
1411 if (UseParallelGC) {
1412 FLAG_SET_DEFAULT(ParallelGCThreads,
1413 Abstract_VM_Version::parallel_worker_threads());
1415 // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
1416 // SurvivorRatio has been set, reset their default values to SurvivorRatio +
1417 // 2. By doing this we make SurvivorRatio also work for Parallel Scavenger.
1418 // See CR 6362902 for details.
1419 if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
1420 if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
1421 FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
1422 }
1423 if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1424 FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1425 }
1426 }
1428 if (UseParallelOldGC) {
1429 // Par compact uses lower default values since they are treated as
1430 // minimums. These are different defaults because of the different
1431 // interpretation and are not ergonomically set.
1432 if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1433 FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1434 }
1435 if (FLAG_IS_DEFAULT(PermMarkSweepDeadRatio)) {
1436 FLAG_SET_DEFAULT(PermMarkSweepDeadRatio, 5);
1437 }
1438 }
1439 }
1440 if (UseNUMA) {
1441 if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
1442 FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
1443 }
1444 // For those collectors or operating systems (eg, Windows) that do
1445 // not support full UseNUMA, we will map to UseNUMAInterleaving for now
1446 UseNUMAInterleaving = true;
1447 }
1448 }
1450 void Arguments::set_g1_gc_flags() {
1451 assert(UseG1GC, "Error");
1452 #ifdef COMPILER1
1453 FastTLABRefill = false;
1454 #endif
1455 FLAG_SET_DEFAULT(ParallelGCThreads,
1456 Abstract_VM_Version::parallel_worker_threads());
1457 if (ParallelGCThreads == 0) {
1458 FLAG_SET_DEFAULT(ParallelGCThreads,
1459 Abstract_VM_Version::parallel_worker_threads());
1460 }
1461 no_shared_spaces();
1463 if (FLAG_IS_DEFAULT(MarkStackSize)) {
1464 FLAG_SET_DEFAULT(MarkStackSize, 128 * TASKQUEUE_SIZE);
1465 }
1466 if (PrintGCDetails && Verbose) {
1467 tty->print_cr("MarkStackSize: %uk MarkStackSizeMax: %uk",
1468 MarkStackSize / K, MarkStackSizeMax / K);
1469 tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1470 }
1472 if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1473 // In G1, we want the default GC overhead goal to be higher than
1474 // say in PS. So we set it here to 10%. Otherwise the heap might
1475 // be expanded more aggressively than we would like it to. In
1476 // fact, even 10% seems to not be high enough in some cases
1477 // (especially small GC stress tests that the main thing they do
1478 // is allocation). We might consider increase it further.
1479 FLAG_SET_DEFAULT(GCTimeRatio, 9);
1480 }
1481 }
1483 void Arguments::set_heap_size() {
1484 if (!FLAG_IS_DEFAULT(DefaultMaxRAMFraction)) {
1485 // Deprecated flag
1486 FLAG_SET_CMDLINE(uintx, MaxRAMFraction, DefaultMaxRAMFraction);
1487 }
1489 const julong phys_mem =
1490 FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
1491 : (julong)MaxRAM;
1493 // If the maximum heap size has not been set with -Xmx,
1494 // then set it as fraction of the size of physical memory,
1495 // respecting the maximum and minimum sizes of the heap.
1496 if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1497 julong reasonable_max = phys_mem / MaxRAMFraction;
1499 if (phys_mem <= MaxHeapSize * MinRAMFraction) {
1500 // Small physical memory, so use a minimum fraction of it for the heap
1501 reasonable_max = phys_mem / MinRAMFraction;
1502 } else {
1503 // Not-small physical memory, so require a heap at least
1504 // as large as MaxHeapSize
1505 reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
1506 }
1507 if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1508 // Limit the heap size to ErgoHeapSizeLimit
1509 reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
1510 }
1511 if (UseCompressedOops) {
1512 // Limit the heap size to the maximum possible when using compressed oops
1513 julong max_coop_heap = (julong)max_heap_for_compressed_oops();
1514 if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
1515 // Heap should be above HeapBaseMinAddress to get zero based compressed oops
1516 // but it should be not less than default MaxHeapSize.
1517 max_coop_heap -= HeapBaseMinAddress;
1518 }
1519 reasonable_max = MIN2(reasonable_max, max_coop_heap);
1520 }
1521 reasonable_max = os::allocatable_physical_memory(reasonable_max);
1523 if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1524 // An initial heap size was specified on the command line,
1525 // so be sure that the maximum size is consistent. Done
1526 // after call to allocatable_physical_memory because that
1527 // method might reduce the allocation size.
1528 reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
1529 }
1531 if (PrintGCDetails && Verbose) {
1532 // Cannot use gclog_or_tty yet.
1533 tty->print_cr(" Maximum heap size " SIZE_FORMAT, reasonable_max);
1534 }
1535 FLAG_SET_ERGO(uintx, MaxHeapSize, (uintx)reasonable_max);
1536 }
1538 // If the initial_heap_size has not been set with InitialHeapSize
1539 // or -Xms, then set it as fraction of the size of physical memory,
1540 // respecting the maximum and minimum sizes of the heap.
1541 if (FLAG_IS_DEFAULT(InitialHeapSize)) {
1542 julong reasonable_minimum = (julong)(OldSize + NewSize);
1544 reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
1546 reasonable_minimum = os::allocatable_physical_memory(reasonable_minimum);
1548 julong reasonable_initial = phys_mem / InitialRAMFraction;
1550 reasonable_initial = MAX2(reasonable_initial, reasonable_minimum);
1551 reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
1553 reasonable_initial = os::allocatable_physical_memory(reasonable_initial);
1555 if (PrintGCDetails && Verbose) {
1556 // Cannot use gclog_or_tty yet.
1557 tty->print_cr(" Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
1558 tty->print_cr(" Minimum heap size " SIZE_FORMAT, (uintx)reasonable_minimum);
1559 }
1560 FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
1561 set_min_heap_size((uintx)reasonable_minimum);
1562 }
1563 }
1565 // This must be called after ergonomics because we want bytecode rewriting
1566 // if the server compiler is used, or if UseSharedSpaces is disabled.
1567 void Arguments::set_bytecode_flags() {
1568 // Better not attempt to store into a read-only space.
1569 if (UseSharedSpaces) {
1570 FLAG_SET_DEFAULT(RewriteBytecodes, false);
1571 FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1572 }
1574 if (!RewriteBytecodes) {
1575 FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1576 }
1577 }
1579 // Aggressive optimization flags -XX:+AggressiveOpts
1580 void Arguments::set_aggressive_opts_flags() {
1581 #ifdef COMPILER2
1582 if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1583 if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1584 FLAG_SET_DEFAULT(EliminateAutoBox, true);
1585 }
1586 if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1587 FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
1588 }
1590 // Feed the cache size setting into the JDK
1591 char buffer[1024];
1592 sprintf(buffer, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
1593 add_property(buffer);
1594 }
1595 if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
1596 FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
1597 }
1598 #endif
1600 if (AggressiveOpts) {
1601 // Sample flag setting code
1602 // if (FLAG_IS_DEFAULT(EliminateZeroing)) {
1603 // FLAG_SET_DEFAULT(EliminateZeroing, true);
1604 // }
1605 }
1606 }
1608 //===========================================================================================================
1609 // Parsing of java.compiler property
1611 void Arguments::process_java_compiler_argument(char* arg) {
1612 // For backwards compatibility, Djava.compiler=NONE or ""
1613 // causes us to switch to -Xint mode UNLESS -Xdebug
1614 // is also specified.
1615 if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
1616 set_java_compiler(true); // "-Djava.compiler[=...]" most recently seen.
1617 }
1618 }
1620 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
1621 _sun_java_launcher = strdup(launcher);
1622 if (strcmp("gamma", _sun_java_launcher) == 0) {
1623 _created_by_gamma_launcher = true;
1624 }
1625 }
1627 bool Arguments::created_by_java_launcher() {
1628 assert(_sun_java_launcher != NULL, "property must have value");
1629 return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
1630 }
1632 bool Arguments::created_by_gamma_launcher() {
1633 return _created_by_gamma_launcher;
1634 }
1636 //===========================================================================================================
1637 // Parsing of main arguments
1639 bool Arguments::verify_interval(uintx val, uintx min,
1640 uintx max, const char* name) {
1641 // Returns true iff value is in the inclusive interval [min..max]
1642 // false, otherwise.
1643 if (val >= min && val <= max) {
1644 return true;
1645 }
1646 jio_fprintf(defaultStream::error_stream(),
1647 "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
1648 " and " UINTX_FORMAT "\n",
1649 name, val, min, max);
1650 return false;
1651 }
1653 bool Arguments::verify_min_value(intx val, intx min, const char* name) {
1654 // Returns true if given value is at least specified min threshold
1655 // false, otherwise.
1656 if (val >= min ) {
1657 return true;
1658 }
1659 jio_fprintf(defaultStream::error_stream(),
1660 "%s of " INTX_FORMAT " is invalid; must be at least " INTX_FORMAT "\n",
1661 name, val, min);
1662 return false;
1663 }
1665 bool Arguments::verify_percentage(uintx value, const char* name) {
1666 if (value <= 100) {
1667 return true;
1668 }
1669 jio_fprintf(defaultStream::error_stream(),
1670 "%s of " UINTX_FORMAT " is invalid; must be between 0 and 100\n",
1671 name, value);
1672 return false;
1673 }
1675 static void force_serial_gc() {
1676 FLAG_SET_DEFAULT(UseSerialGC, true);
1677 FLAG_SET_DEFAULT(UseParNewGC, false);
1678 FLAG_SET_DEFAULT(UseConcMarkSweepGC, false);
1679 FLAG_SET_DEFAULT(CMSIncrementalMode, false); // special CMS suboption
1680 FLAG_SET_DEFAULT(UseParallelGC, false);
1681 FLAG_SET_DEFAULT(UseParallelOldGC, false);
1682 FLAG_SET_DEFAULT(UseG1GC, false);
1683 }
1685 static bool verify_serial_gc_flags() {
1686 return (UseSerialGC &&
1687 !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
1688 UseParallelGC || UseParallelOldGC));
1689 }
1691 // check if do gclog rotation
1692 // +UseGCLogFileRotation is a must,
1693 // no gc log rotation when log file not supplied or
1694 // NumberOfGCLogFiles is 0, or GCLogFileSize is 0
1695 void check_gclog_consistency() {
1696 if (UseGCLogFileRotation) {
1697 if ((Arguments::gc_log_filename() == NULL) ||
1698 (NumberOfGCLogFiles == 0) ||
1699 (GCLogFileSize == 0)) {
1700 jio_fprintf(defaultStream::output_stream(),
1701 "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=<num_of_files> -XX:GCLogFileSize=<num_of_size>\n"
1702 "where num_of_file > 0 and num_of_size > 0\n"
1703 "GC log rotation is turned off\n");
1704 UseGCLogFileRotation = false;
1705 }
1706 }
1708 if (UseGCLogFileRotation && GCLogFileSize < 8*K) {
1709 FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
1710 jio_fprintf(defaultStream::output_stream(),
1711 "GCLogFileSize changed to minimum 8K\n");
1712 }
1713 }
1715 // Check consistency of GC selection
1716 bool Arguments::check_gc_consistency() {
1717 check_gclog_consistency();
1718 bool status = true;
1719 // Ensure that the user has not selected conflicting sets
1720 // of collectors. [Note: this check is merely a user convenience;
1721 // collectors over-ride each other so that only a non-conflicting
1722 // set is selected; however what the user gets is not what they
1723 // may have expected from the combination they asked for. It's
1724 // better to reduce user confusion by not allowing them to
1725 // select conflicting combinations.
1726 uint i = 0;
1727 if (UseSerialGC) i++;
1728 if (UseConcMarkSweepGC || UseParNewGC) i++;
1729 if (UseParallelGC || UseParallelOldGC) i++;
1730 if (UseG1GC) i++;
1731 if (i > 1) {
1732 jio_fprintf(defaultStream::error_stream(),
1733 "Conflicting collector combinations in option list; "
1734 "please refer to the release notes for the combinations "
1735 "allowed\n");
1736 status = false;
1737 }
1739 return status;
1740 }
1742 // Check stack pages settings
1743 bool Arguments::check_stack_pages()
1744 {
1745 bool status = true;
1746 status = status && verify_min_value(StackYellowPages, 1, "StackYellowPages");
1747 status = status && verify_min_value(StackRedPages, 1, "StackRedPages");
1748 // greater stack shadow pages can't generate instruction to bang stack
1749 status = status && verify_interval(StackShadowPages, 1, 50, "StackShadowPages");
1750 return status;
1751 }
1753 // Check the consistency of vm_init_args
1754 bool Arguments::check_vm_args_consistency() {
1755 // Method for adding checks for flag consistency.
1756 // The intent is to warn the user of all possible conflicts,
1757 // before returning an error.
1758 // Note: Needs platform-dependent factoring.
1759 bool status = true;
1761 #if ( (defined(COMPILER2) && defined(SPARC)))
1762 // NOTE: The call to VM_Version_init depends on the fact that VM_Version_init
1763 // on sparc doesn't require generation of a stub as is the case on, e.g.,
1764 // x86. Normally, VM_Version_init must be called from init_globals in
1765 // init.cpp, which is called by the initial java thread *after* arguments
1766 // have been parsed. VM_Version_init gets called twice on sparc.
1767 extern void VM_Version_init();
1768 VM_Version_init();
1769 if (!VM_Version::has_v9()) {
1770 jio_fprintf(defaultStream::error_stream(),
1771 "V8 Machine detected, Server requires V9\n");
1772 status = false;
1773 }
1774 #endif /* COMPILER2 && SPARC */
1776 // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
1777 // builds so the cost of stack banging can be measured.
1778 #if (defined(PRODUCT) && defined(SOLARIS))
1779 if (!UseBoundThreads && !UseStackBanging) {
1780 jio_fprintf(defaultStream::error_stream(),
1781 "-UseStackBanging conflicts with -UseBoundThreads\n");
1783 status = false;
1784 }
1785 #endif
1787 if (TLABRefillWasteFraction == 0) {
1788 jio_fprintf(defaultStream::error_stream(),
1789 "TLABRefillWasteFraction should be a denominator, "
1790 "not " SIZE_FORMAT "\n",
1791 TLABRefillWasteFraction);
1792 status = false;
1793 }
1795 status = status && verify_percentage(AdaptiveSizePolicyWeight,
1796 "AdaptiveSizePolicyWeight");
1797 status = status && verify_percentage(AdaptivePermSizeWeight, "AdaptivePermSizeWeight");
1798 status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
1799 status = status && verify_percentage(MinHeapFreeRatio, "MinHeapFreeRatio");
1800 status = status && verify_percentage(MaxHeapFreeRatio, "MaxHeapFreeRatio");
1802 if (MinHeapFreeRatio > MaxHeapFreeRatio) {
1803 jio_fprintf(defaultStream::error_stream(),
1804 "MinHeapFreeRatio (" UINTX_FORMAT ") must be less than or "
1805 "equal to MaxHeapFreeRatio (" UINTX_FORMAT ")\n",
1806 MinHeapFreeRatio, MaxHeapFreeRatio);
1807 status = false;
1808 }
1809 // Keeping the heap 100% free is hard ;-) so limit it to 99%.
1810 MinHeapFreeRatio = MIN2(MinHeapFreeRatio, (uintx) 99);
1812 if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
1813 MarkSweepAlwaysCompactCount = 1; // Move objects every gc.
1814 }
1816 if (UseParallelOldGC && ParallelOldGCSplitALot) {
1817 // Settings to encourage splitting.
1818 if (!FLAG_IS_CMDLINE(NewRatio)) {
1819 FLAG_SET_CMDLINE(intx, NewRatio, 2);
1820 }
1821 if (!FLAG_IS_CMDLINE(ScavengeBeforeFullGC)) {
1822 FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
1823 }
1824 }
1826 status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1827 status = status && verify_percentage(GCTimeLimit, "GCTimeLimit");
1828 if (GCTimeLimit == 100) {
1829 // Turn off gc-overhead-limit-exceeded checks
1830 FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
1831 }
1833 status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1835 status = status && check_gc_consistency();
1836 status = status && check_stack_pages();
1838 if (_has_alloc_profile) {
1839 if (UseParallelGC || UseParallelOldGC) {
1840 jio_fprintf(defaultStream::error_stream(),
1841 "error: invalid argument combination.\n"
1842 "Allocation profiling (-Xaprof) cannot be used together with "
1843 "Parallel GC (-XX:+UseParallelGC or -XX:+UseParallelOldGC).\n");
1844 status = false;
1845 }
1846 if (UseConcMarkSweepGC) {
1847 jio_fprintf(defaultStream::error_stream(),
1848 "error: invalid argument combination.\n"
1849 "Allocation profiling (-Xaprof) cannot be used together with "
1850 "the CMS collector (-XX:+UseConcMarkSweepGC).\n");
1851 status = false;
1852 }
1853 }
1855 if (CMSIncrementalMode) {
1856 if (!UseConcMarkSweepGC) {
1857 jio_fprintf(defaultStream::error_stream(),
1858 "error: invalid argument combination.\n"
1859 "The CMS collector (-XX:+UseConcMarkSweepGC) must be "
1860 "selected in order\nto use CMSIncrementalMode.\n");
1861 status = false;
1862 } else {
1863 status = status && verify_percentage(CMSIncrementalDutyCycle,
1864 "CMSIncrementalDutyCycle");
1865 status = status && verify_percentage(CMSIncrementalDutyCycleMin,
1866 "CMSIncrementalDutyCycleMin");
1867 status = status && verify_percentage(CMSIncrementalSafetyFactor,
1868 "CMSIncrementalSafetyFactor");
1869 status = status && verify_percentage(CMSIncrementalOffset,
1870 "CMSIncrementalOffset");
1871 status = status && verify_percentage(CMSExpAvgFactor,
1872 "CMSExpAvgFactor");
1873 // If it was not set on the command line, set
1874 // CMSInitiatingOccupancyFraction to 1 so icms can initiate cycles early.
1875 if (CMSInitiatingOccupancyFraction < 0) {
1876 FLAG_SET_DEFAULT(CMSInitiatingOccupancyFraction, 1);
1877 }
1878 }
1879 }
1881 // CMS space iteration, which FLSVerifyAllHeapreferences entails,
1882 // insists that we hold the requisite locks so that the iteration is
1883 // MT-safe. For the verification at start-up and shut-down, we don't
1884 // yet have a good way of acquiring and releasing these locks,
1885 // which are not visible at the CollectedHeap level. We want to
1886 // be able to acquire these locks and then do the iteration rather
1887 // than just disable the lock verification. This will be fixed under
1888 // bug 4788986.
1889 if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
1890 if (VerifyGCStartAt == 0) {
1891 warning("Heap verification at start-up disabled "
1892 "(due to current incompatibility with FLSVerifyAllHeapReferences)");
1893 VerifyGCStartAt = 1; // Disable verification at start-up
1894 }
1895 if (VerifyBeforeExit) {
1896 warning("Heap verification at shutdown disabled "
1897 "(due to current incompatibility with FLSVerifyAllHeapReferences)");
1898 VerifyBeforeExit = false; // Disable verification at shutdown
1899 }
1900 }
1902 // Note: only executed in non-PRODUCT mode
1903 if (!UseAsyncConcMarkSweepGC &&
1904 (ExplicitGCInvokesConcurrent ||
1905 ExplicitGCInvokesConcurrentAndUnloadsClasses)) {
1906 jio_fprintf(defaultStream::error_stream(),
1907 "error: +ExplictGCInvokesConcurrent[AndUnloadsClasses] conflicts"
1908 " with -UseAsyncConcMarkSweepGC");
1909 status = false;
1910 }
1912 status = status && verify_min_value(ParGCArrayScanChunk, 1, "ParGCArrayScanChunk");
1914 #ifndef SERIALGC
1915 if (UseG1GC) {
1916 status = status && verify_percentage(InitiatingHeapOccupancyPercent,
1917 "InitiatingHeapOccupancyPercent");
1918 status = status && verify_min_value(G1RefProcDrainInterval, 1,
1919 "G1RefProcDrainInterval");
1920 status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
1921 "G1ConcMarkStepDurationMillis");
1922 }
1923 #endif
1925 status = status && verify_interval(RefDiscoveryPolicy,
1926 ReferenceProcessor::DiscoveryPolicyMin,
1927 ReferenceProcessor::DiscoveryPolicyMax,
1928 "RefDiscoveryPolicy");
1930 // Limit the lower bound of this flag to 1 as it is used in a division
1931 // expression.
1932 status = status && verify_interval(TLABWasteTargetPercent,
1933 1, 100, "TLABWasteTargetPercent");
1935 status = status && verify_object_alignment();
1937 return status;
1938 }
1940 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
1941 const char* option_type) {
1942 if (ignore) return false;
1944 const char* spacer = " ";
1945 if (option_type == NULL) {
1946 option_type = ++spacer; // Set both to the empty string.
1947 }
1949 if (os::obsolete_option(option)) {
1950 jio_fprintf(defaultStream::error_stream(),
1951 "Obsolete %s%soption: %s\n", option_type, spacer,
1952 option->optionString);
1953 return false;
1954 } else {
1955 jio_fprintf(defaultStream::error_stream(),
1956 "Unrecognized %s%soption: %s\n", option_type, spacer,
1957 option->optionString);
1958 return true;
1959 }
1960 }
1962 static const char* user_assertion_options[] = {
1963 "-da", "-ea", "-disableassertions", "-enableassertions", 0
1964 };
1966 static const char* system_assertion_options[] = {
1967 "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
1968 };
1970 // Return true if any of the strings in null-terminated array 'names' matches.
1971 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
1972 // the option must match exactly.
1973 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
1974 bool tail_allowed) {
1975 for (/* empty */; *names != NULL; ++names) {
1976 if (match_option(option, *names, tail)) {
1977 if (**tail == '\0' || tail_allowed && **tail == ':') {
1978 return true;
1979 }
1980 }
1981 }
1982 return false;
1983 }
1985 bool Arguments::parse_uintx(const char* value,
1986 uintx* uintx_arg,
1987 uintx min_size) {
1989 // Check the sign first since atomull() parses only unsigned values.
1990 bool value_is_positive = !(*value == '-');
1992 if (value_is_positive) {
1993 julong n;
1994 bool good_return = atomull(value, &n);
1995 if (good_return) {
1996 bool above_minimum = n >= min_size;
1997 bool value_is_too_large = n > max_uintx;
1999 if (above_minimum && !value_is_too_large) {
2000 *uintx_arg = n;
2001 return true;
2002 }
2003 }
2004 }
2005 return false;
2006 }
2008 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
2009 julong* long_arg,
2010 julong min_size) {
2011 if (!atomull(s, long_arg)) return arg_unreadable;
2012 return check_memory_size(*long_arg, min_size);
2013 }
2015 // Parse JavaVMInitArgs structure
2017 jint Arguments::parse_vm_init_args(const JavaVMInitArgs* args) {
2018 // For components of the system classpath.
2019 SysClassPath scp(Arguments::get_sysclasspath());
2020 bool scp_assembly_required = false;
2022 // Save default settings for some mode flags
2023 Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
2024 Arguments::_UseOnStackReplacement = UseOnStackReplacement;
2025 Arguments::_ClipInlining = ClipInlining;
2026 Arguments::_BackgroundCompilation = BackgroundCompilation;
2028 // Setup flags for mixed which is the default
2029 set_mode_flags(_mixed);
2031 // Parse JAVA_TOOL_OPTIONS environment variable (if present)
2032 jint result = parse_java_tool_options_environment_variable(&scp, &scp_assembly_required);
2033 if (result != JNI_OK) {
2034 return result;
2035 }
2037 // Parse JavaVMInitArgs structure passed in
2038 result = parse_each_vm_init_arg(args, &scp, &scp_assembly_required, COMMAND_LINE);
2039 if (result != JNI_OK) {
2040 return result;
2041 }
2043 if (AggressiveOpts) {
2044 // Insert alt-rt.jar between user-specified bootclasspath
2045 // prefix and the default bootclasspath. os::set_boot_path()
2046 // uses meta_index_dir as the default bootclasspath directory.
2047 const char* altclasses_jar = "alt-rt.jar";
2048 size_t altclasses_path_len = strlen(get_meta_index_dir()) + 1 +
2049 strlen(altclasses_jar);
2050 char* altclasses_path = NEW_C_HEAP_ARRAY(char, altclasses_path_len);
2051 strcpy(altclasses_path, get_meta_index_dir());
2052 strcat(altclasses_path, altclasses_jar);
2053 scp.add_suffix_to_prefix(altclasses_path);
2054 scp_assembly_required = true;
2055 FREE_C_HEAP_ARRAY(char, altclasses_path);
2056 }
2058 // Parse _JAVA_OPTIONS environment variable (if present) (mimics classic VM)
2059 result = parse_java_options_environment_variable(&scp, &scp_assembly_required);
2060 if (result != JNI_OK) {
2061 return result;
2062 }
2064 // Do final processing now that all arguments have been parsed
2065 result = finalize_vm_init_args(&scp, scp_assembly_required);
2066 if (result != JNI_OK) {
2067 return result;
2068 }
2070 return JNI_OK;
2071 }
2073 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
2074 SysClassPath* scp_p,
2075 bool* scp_assembly_required_p,
2076 FlagValueOrigin origin) {
2077 // Remaining part of option string
2078 const char* tail;
2080 // iterate over arguments
2081 for (int index = 0; index < args->nOptions; index++) {
2082 bool is_absolute_path = false; // for -agentpath vs -agentlib
2084 const JavaVMOption* option = args->options + index;
2086 if (!match_option(option, "-Djava.class.path", &tail) &&
2087 !match_option(option, "-Dsun.java.command", &tail) &&
2088 !match_option(option, "-Dsun.java.launcher", &tail)) {
2090 // add all jvm options to the jvm_args string. This string
2091 // is used later to set the java.vm.args PerfData string constant.
2092 // the -Djava.class.path and the -Dsun.java.command options are
2093 // omitted from jvm_args string as each have their own PerfData
2094 // string constant object.
2095 build_jvm_args(option->optionString);
2096 }
2098 // -verbose:[class/gc/jni]
2099 if (match_option(option, "-verbose", &tail)) {
2100 if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2101 FLAG_SET_CMDLINE(bool, TraceClassLoading, true);
2102 FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
2103 } else if (!strcmp(tail, ":gc")) {
2104 FLAG_SET_CMDLINE(bool, PrintGC, true);
2105 } else if (!strcmp(tail, ":jni")) {
2106 FLAG_SET_CMDLINE(bool, PrintJNIResolving, true);
2107 }
2108 // -da / -ea / -disableassertions / -enableassertions
2109 // These accept an optional class/package name separated by a colon, e.g.,
2110 // -da:java.lang.Thread.
2111 } else if (match_option(option, user_assertion_options, &tail, true)) {
2112 bool enable = option->optionString[1] == 'e'; // char after '-' is 'e'
2113 if (*tail == '\0') {
2114 JavaAssertions::setUserClassDefault(enable);
2115 } else {
2116 assert(*tail == ':', "bogus match by match_option()");
2117 JavaAssertions::addOption(tail + 1, enable);
2118 }
2119 // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2120 } else if (match_option(option, system_assertion_options, &tail, false)) {
2121 bool enable = option->optionString[1] == 'e'; // char after '-' is 'e'
2122 JavaAssertions::setSystemClassDefault(enable);
2123 // -bootclasspath:
2124 } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2125 scp_p->reset_path(tail);
2126 *scp_assembly_required_p = true;
2127 // -bootclasspath/a:
2128 } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2129 scp_p->add_suffix(tail);
2130 *scp_assembly_required_p = true;
2131 // -bootclasspath/p:
2132 } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2133 scp_p->add_prefix(tail);
2134 *scp_assembly_required_p = true;
2135 // -Xrun
2136 } else if (match_option(option, "-Xrun", &tail)) {
2137 if (tail != NULL) {
2138 const char* pos = strchr(tail, ':');
2139 size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2140 char* name = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len + 1), tail, len);
2141 name[len] = '\0';
2143 char *options = NULL;
2144 if(pos != NULL) {
2145 size_t len2 = strlen(pos+1) + 1; // options start after ':'. Final zero must be copied.
2146 options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2), pos+1, len2);
2147 }
2148 #ifdef JVMTI_KERNEL
2149 if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2150 warning("profiling and debugging agents are not supported with Kernel VM");
2151 } else
2152 #endif // JVMTI_KERNEL
2153 add_init_library(name, options);
2154 }
2155 // -agentlib and -agentpath
2156 } else if (match_option(option, "-agentlib:", &tail) ||
2157 (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2158 if(tail != NULL) {
2159 const char* pos = strchr(tail, '=');
2160 size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2161 char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1), tail, len);
2162 name[len] = '\0';
2164 char *options = NULL;
2165 if(pos != NULL) {
2166 options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(pos + 1) + 1), pos + 1);
2167 }
2168 #ifdef JVMTI_KERNEL
2169 if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2170 warning("profiling and debugging agents are not supported with Kernel VM");
2171 } else
2172 #endif // JVMTI_KERNEL
2173 add_init_agent(name, options, is_absolute_path);
2175 }
2176 // -javaagent
2177 } else if (match_option(option, "-javaagent:", &tail)) {
2178 if(tail != NULL) {
2179 char *options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(tail) + 1), tail);
2180 add_init_agent("instrument", options, false);
2181 }
2182 // -Xnoclassgc
2183 } else if (match_option(option, "-Xnoclassgc", &tail)) {
2184 FLAG_SET_CMDLINE(bool, ClassUnloading, false);
2185 // -Xincgc: i-CMS
2186 } else if (match_option(option, "-Xincgc", &tail)) {
2187 FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2188 FLAG_SET_CMDLINE(bool, CMSIncrementalMode, true);
2189 // -Xnoincgc: no i-CMS
2190 } else if (match_option(option, "-Xnoincgc", &tail)) {
2191 FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2192 FLAG_SET_CMDLINE(bool, CMSIncrementalMode, false);
2193 // -Xconcgc
2194 } else if (match_option(option, "-Xconcgc", &tail)) {
2195 FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2196 // -Xnoconcgc
2197 } else if (match_option(option, "-Xnoconcgc", &tail)) {
2198 FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2199 // -Xbatch
2200 } else if (match_option(option, "-Xbatch", &tail)) {
2201 FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2202 // -Xmn for compatibility with other JVM vendors
2203 } else if (match_option(option, "-Xmn", &tail)) {
2204 julong long_initial_eden_size = 0;
2205 ArgsRange errcode = parse_memory_size(tail, &long_initial_eden_size, 1);
2206 if (errcode != arg_in_range) {
2207 jio_fprintf(defaultStream::error_stream(),
2208 "Invalid initial eden size: %s\n", option->optionString);
2209 describe_range_error(errcode);
2210 return JNI_EINVAL;
2211 }
2212 FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_eden_size);
2213 FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_eden_size);
2214 // -Xms
2215 } else if (match_option(option, "-Xms", &tail)) {
2216 julong long_initial_heap_size = 0;
2217 ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 1);
2218 if (errcode != arg_in_range) {
2219 jio_fprintf(defaultStream::error_stream(),
2220 "Invalid initial heap size: %s\n", option->optionString);
2221 describe_range_error(errcode);
2222 return JNI_EINVAL;
2223 }
2224 FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
2225 // Currently the minimum size and the initial heap sizes are the same.
2226 set_min_heap_size(InitialHeapSize);
2227 // -Xmx
2228 } else if (match_option(option, "-Xmx", &tail)) {
2229 julong long_max_heap_size = 0;
2230 ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
2231 if (errcode != arg_in_range) {
2232 jio_fprintf(defaultStream::error_stream(),
2233 "Invalid maximum heap size: %s\n", option->optionString);
2234 describe_range_error(errcode);
2235 return JNI_EINVAL;
2236 }
2237 FLAG_SET_CMDLINE(uintx, MaxHeapSize, (uintx)long_max_heap_size);
2238 // Xmaxf
2239 } else if (match_option(option, "-Xmaxf", &tail)) {
2240 int maxf = (int)(atof(tail) * 100);
2241 if (maxf < 0 || maxf > 100) {
2242 jio_fprintf(defaultStream::error_stream(),
2243 "Bad max heap free percentage size: %s\n",
2244 option->optionString);
2245 return JNI_EINVAL;
2246 } else {
2247 FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf);
2248 }
2249 // Xminf
2250 } else if (match_option(option, "-Xminf", &tail)) {
2251 int minf = (int)(atof(tail) * 100);
2252 if (minf < 0 || minf > 100) {
2253 jio_fprintf(defaultStream::error_stream(),
2254 "Bad min heap free percentage size: %s\n",
2255 option->optionString);
2256 return JNI_EINVAL;
2257 } else {
2258 FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf);
2259 }
2260 // -Xss
2261 } else if (match_option(option, "-Xss", &tail)) {
2262 julong long_ThreadStackSize = 0;
2263 ArgsRange errcode = parse_memory_size(tail, &long_ThreadStackSize, 1000);
2264 if (errcode != arg_in_range) {
2265 jio_fprintf(defaultStream::error_stream(),
2266 "Invalid thread stack size: %s\n", option->optionString);
2267 describe_range_error(errcode);
2268 return JNI_EINVAL;
2269 }
2270 // Internally track ThreadStackSize in units of 1024 bytes.
2271 FLAG_SET_CMDLINE(intx, ThreadStackSize,
2272 round_to((int)long_ThreadStackSize, K) / K);
2273 // -Xoss
2274 } else if (match_option(option, "-Xoss", &tail)) {
2275 // HotSpot does not have separate native and Java stacks, ignore silently for compatibility
2276 // -Xmaxjitcodesize
2277 } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
2278 match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
2279 julong long_ReservedCodeCacheSize = 0;
2280 ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize,
2281 (size_t)InitialCodeCacheSize);
2282 if (errcode != arg_in_range) {
2283 jio_fprintf(defaultStream::error_stream(),
2284 "Invalid maximum code cache size: %s. Should be greater than InitialCodeCacheSize=%dK\n",
2285 option->optionString, InitialCodeCacheSize/K);
2286 describe_range_error(errcode);
2287 return JNI_EINVAL;
2288 }
2289 FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
2290 // -green
2291 } else if (match_option(option, "-green", &tail)) {
2292 jio_fprintf(defaultStream::error_stream(),
2293 "Green threads support not available\n");
2294 return JNI_EINVAL;
2295 // -native
2296 } else if (match_option(option, "-native", &tail)) {
2297 // HotSpot always uses native threads, ignore silently for compatibility
2298 // -Xsqnopause
2299 } else if (match_option(option, "-Xsqnopause", &tail)) {
2300 // EVM option, ignore silently for compatibility
2301 // -Xrs
2302 } else if (match_option(option, "-Xrs", &tail)) {
2303 // Classic/EVM option, new functionality
2304 FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true);
2305 } else if (match_option(option, "-Xusealtsigs", &tail)) {
2306 // change default internal VM signals used - lower case for back compat
2307 FLAG_SET_CMDLINE(bool, UseAltSigs, true);
2308 // -Xoptimize
2309 } else if (match_option(option, "-Xoptimize", &tail)) {
2310 // EVM option, ignore silently for compatibility
2311 // -Xprof
2312 } else if (match_option(option, "-Xprof", &tail)) {
2313 #ifndef FPROF_KERNEL
2314 _has_profile = true;
2315 #else // FPROF_KERNEL
2316 // do we have to exit?
2317 warning("Kernel VM does not support flat profiling.");
2318 #endif // FPROF_KERNEL
2319 // -Xaprof
2320 } else if (match_option(option, "-Xaprof", &tail)) {
2321 _has_alloc_profile = true;
2322 // -Xconcurrentio
2323 } else if (match_option(option, "-Xconcurrentio", &tail)) {
2324 FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true);
2325 FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2326 FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1);
2327 FLAG_SET_CMDLINE(bool, UseTLAB, false);
2328 FLAG_SET_CMDLINE(uintx, NewSizeThreadIncrease, 16 * K); // 20Kb per thread added to new generation
2330 // -Xinternalversion
2331 } else if (match_option(option, "-Xinternalversion", &tail)) {
2332 jio_fprintf(defaultStream::output_stream(), "%s\n",
2333 VM_Version::internal_vm_info_string());
2334 vm_exit(0);
2335 #ifndef PRODUCT
2336 // -Xprintflags
2337 } else if (match_option(option, "-Xprintflags", &tail)) {
2338 CommandLineFlags::printFlags(tty, false);
2339 vm_exit(0);
2340 #endif
2341 // -D
2342 } else if (match_option(option, "-D", &tail)) {
2343 if (!add_property(tail)) {
2344 return JNI_ENOMEM;
2345 }
2346 // Out of the box management support
2347 if (match_option(option, "-Dcom.sun.management", &tail)) {
2348 FLAG_SET_CMDLINE(bool, ManagementServer, true);
2349 }
2350 // -Xint
2351 } else if (match_option(option, "-Xint", &tail)) {
2352 set_mode_flags(_int);
2353 // -Xmixed
2354 } else if (match_option(option, "-Xmixed", &tail)) {
2355 set_mode_flags(_mixed);
2356 // -Xcomp
2357 } else if (match_option(option, "-Xcomp", &tail)) {
2358 // for testing the compiler; turn off all flags that inhibit compilation
2359 set_mode_flags(_comp);
2361 // -Xshare:dump
2362 } else if (match_option(option, "-Xshare:dump", &tail)) {
2363 #ifdef TIERED
2364 FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
2365 set_mode_flags(_int); // Prevent compilation, which creates objects
2366 #elif defined(COMPILER2)
2367 vm_exit_during_initialization(
2368 "Dumping a shared archive is not supported on the Server JVM.", NULL);
2369 #elif defined(KERNEL)
2370 vm_exit_during_initialization(
2371 "Dumping a shared archive is not supported on the Kernel JVM.", NULL);
2372 #else
2373 FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
2374 set_mode_flags(_int); // Prevent compilation, which creates objects
2375 #endif
2376 // -Xshare:on
2377 } else if (match_option(option, "-Xshare:on", &tail)) {
2378 FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2379 FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
2380 // -Xshare:auto
2381 } else if (match_option(option, "-Xshare:auto", &tail)) {
2382 FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2383 FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2384 // -Xshare:off
2385 } else if (match_option(option, "-Xshare:off", &tail)) {
2386 FLAG_SET_CMDLINE(bool, UseSharedSpaces, false);
2387 FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2389 // -Xverify
2390 } else if (match_option(option, "-Xverify", &tail)) {
2391 if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
2392 FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true);
2393 FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2394 } else if (strcmp(tail, ":remote") == 0) {
2395 FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2396 FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2397 } else if (strcmp(tail, ":none") == 0) {
2398 FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2399 FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false);
2400 } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
2401 return JNI_EINVAL;
2402 }
2403 // -Xdebug
2404 } else if (match_option(option, "-Xdebug", &tail)) {
2405 // note this flag has been used, then ignore
2406 set_xdebug_mode(true);
2407 // -Xnoagent
2408 } else if (match_option(option, "-Xnoagent", &tail)) {
2409 // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
2410 } else if (match_option(option, "-Xboundthreads", &tail)) {
2411 // Bind user level threads to kernel threads (Solaris only)
2412 FLAG_SET_CMDLINE(bool, UseBoundThreads, true);
2413 } else if (match_option(option, "-Xloggc:", &tail)) {
2414 // Redirect GC output to the file. -Xloggc:<filename>
2415 // ostream_init_log(), when called will use this filename
2416 // to initialize a fileStream.
2417 _gc_log_filename = strdup(tail);
2418 FLAG_SET_CMDLINE(bool, PrintGC, true);
2419 FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);
2421 // JNI hooks
2422 } else if (match_option(option, "-Xcheck", &tail)) {
2423 if (!strcmp(tail, ":jni")) {
2424 CheckJNICalls = true;
2425 } else if (is_bad_option(option, args->ignoreUnrecognized,
2426 "check")) {
2427 return JNI_EINVAL;
2428 }
2429 } else if (match_option(option, "vfprintf", &tail)) {
2430 _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
2431 } else if (match_option(option, "exit", &tail)) {
2432 _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
2433 } else if (match_option(option, "abort", &tail)) {
2434 _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
2435 // -XX:+AggressiveHeap
2436 } else if (match_option(option, "-XX:+AggressiveHeap", &tail)) {
2438 // This option inspects the machine and attempts to set various
2439 // parameters to be optimal for long-running, memory allocation
2440 // intensive jobs. It is intended for machines with large
2441 // amounts of cpu and memory.
2443 // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
2444 // VM, but we may not be able to represent the total physical memory
2445 // available (like having 8gb of memory on a box but using a 32bit VM).
2446 // Thus, we need to make sure we're using a julong for intermediate
2447 // calculations.
2448 julong initHeapSize;
2449 julong total_memory = os::physical_memory();
2451 if (total_memory < (julong)256*M) {
2452 jio_fprintf(defaultStream::error_stream(),
2453 "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
2454 vm_exit(1);
2455 }
2457 // The heap size is half of available memory, or (at most)
2458 // all of possible memory less 160mb (leaving room for the OS
2459 // when using ISM). This is the maximum; because adaptive sizing
2460 // is turned on below, the actual space used may be smaller.
2462 initHeapSize = MIN2(total_memory / (julong)2,
2463 total_memory - (julong)160*M);
2465 // Make sure that if we have a lot of memory we cap the 32 bit
2466 // process space. The 64bit VM version of this function is a nop.
2467 initHeapSize = os::allocatable_physical_memory(initHeapSize);
2469 // The perm gen is separate but contiguous with the
2470 // object heap (and is reserved with it) so subtract it
2471 // from the heap size.
2472 if (initHeapSize > MaxPermSize) {
2473 initHeapSize = initHeapSize - MaxPermSize;
2474 } else {
2475 warning("AggressiveHeap and MaxPermSize values may conflict");
2476 }
2478 if (FLAG_IS_DEFAULT(MaxHeapSize)) {
2479 FLAG_SET_CMDLINE(uintx, MaxHeapSize, initHeapSize);
2480 FLAG_SET_CMDLINE(uintx, InitialHeapSize, initHeapSize);
2481 // Currently the minimum size and the initial heap sizes are the same.
2482 set_min_heap_size(initHeapSize);
2483 }
2484 if (FLAG_IS_DEFAULT(NewSize)) {
2485 // Make the young generation 3/8ths of the total heap.
2486 FLAG_SET_CMDLINE(uintx, NewSize,
2487 ((julong)MaxHeapSize / (julong)8) * (julong)3);
2488 FLAG_SET_CMDLINE(uintx, MaxNewSize, NewSize);
2489 }
2491 FLAG_SET_DEFAULT(UseLargePages, true);
2493 // Increase some data structure sizes for efficiency
2494 FLAG_SET_CMDLINE(uintx, BaseFootPrintEstimate, MaxHeapSize);
2495 FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2496 FLAG_SET_CMDLINE(uintx, TLABSize, 256*K);
2498 // See the OldPLABSize comment below, but replace 'after promotion'
2499 // with 'after copying'. YoungPLABSize is the size of the survivor
2500 // space per-gc-thread buffers. The default is 4kw.
2501 FLAG_SET_CMDLINE(uintx, YoungPLABSize, 256*K); // Note: this is in words
2503 // OldPLABSize is the size of the buffers in the old gen that
2504 // UseParallelGC uses to promote live data that doesn't fit in the
2505 // survivor spaces. At any given time, there's one for each gc thread.
2506 // The default size is 1kw. These buffers are rarely used, since the
2507 // survivor spaces are usually big enough. For specjbb, however, there
2508 // are occasions when there's lots of live data in the young gen
2509 // and we end up promoting some of it. We don't have a definite
2510 // explanation for why bumping OldPLABSize helps, but the theory
2511 // is that a bigger PLAB results in retaining something like the
2512 // original allocation order after promotion, which improves mutator
2513 // locality. A minor effect may be that larger PLABs reduce the
2514 // number of PLAB allocation events during gc. The value of 8kw
2515 // was arrived at by experimenting with specjbb.
2516 FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K); // Note: this is in words
2518 // CompilationPolicyChoice=0 causes the server compiler to adopt
2519 // a more conservative which-method-do-I-compile policy when one
2520 // of the counters maintained by the interpreter trips. The
2521 // result is reduced startup time and improved specjbb and
2522 // alacrity performance. Zero is the default, but we set it
2523 // explicitly here in case the default changes.
2524 // See runtime/compilationPolicy.*.
2525 FLAG_SET_CMDLINE(intx, CompilationPolicyChoice, 0);
2527 // Enable parallel GC and adaptive generation sizing
2528 FLAG_SET_CMDLINE(bool, UseParallelGC, true);
2529 FLAG_SET_DEFAULT(ParallelGCThreads,
2530 Abstract_VM_Version::parallel_worker_threads());
2532 // Encourage steady state memory management
2533 FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);
2535 // This appears to improve mutator locality
2536 FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2538 // Get around early Solaris scheduling bug
2539 // (affinity vs other jobs on system)
2540 // but disallow DR and offlining (5008695).
2541 FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true);
2543 } else if (match_option(option, "-XX:+NeverTenure", &tail)) {
2544 // The last option must always win.
2545 FLAG_SET_CMDLINE(bool, AlwaysTenure, false);
2546 FLAG_SET_CMDLINE(bool, NeverTenure, true);
2547 } else if (match_option(option, "-XX:+AlwaysTenure", &tail)) {
2548 // The last option must always win.
2549 FLAG_SET_CMDLINE(bool, NeverTenure, false);
2550 FLAG_SET_CMDLINE(bool, AlwaysTenure, true);
2551 } else if (match_option(option, "-XX:+CMSPermGenSweepingEnabled", &tail) ||
2552 match_option(option, "-XX:-CMSPermGenSweepingEnabled", &tail)) {
2553 jio_fprintf(defaultStream::error_stream(),
2554 "Please use CMSClassUnloadingEnabled in place of "
2555 "CMSPermGenSweepingEnabled in the future\n");
2556 } else if (match_option(option, "-XX:+UseGCTimeLimit", &tail)) {
2557 FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, true);
2558 jio_fprintf(defaultStream::error_stream(),
2559 "Please use -XX:+UseGCOverheadLimit in place of "
2560 "-XX:+UseGCTimeLimit in the future\n");
2561 } else if (match_option(option, "-XX:-UseGCTimeLimit", &tail)) {
2562 FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, false);
2563 jio_fprintf(defaultStream::error_stream(),
2564 "Please use -XX:-UseGCOverheadLimit in place of "
2565 "-XX:-UseGCTimeLimit in the future\n");
2566 // The TLE options are for compatibility with 1.3 and will be
2567 // removed without notice in a future release. These options
2568 // are not to be documented.
2569 } else if (match_option(option, "-XX:MaxTLERatio=", &tail)) {
2570 // No longer used.
2571 } else if (match_option(option, "-XX:+ResizeTLE", &tail)) {
2572 FLAG_SET_CMDLINE(bool, ResizeTLAB, true);
2573 } else if (match_option(option, "-XX:-ResizeTLE", &tail)) {
2574 FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2575 } else if (match_option(option, "-XX:+PrintTLE", &tail)) {
2576 FLAG_SET_CMDLINE(bool, PrintTLAB, true);
2577 } else if (match_option(option, "-XX:-PrintTLE", &tail)) {
2578 FLAG_SET_CMDLINE(bool, PrintTLAB, false);
2579 } else if (match_option(option, "-XX:TLEFragmentationRatio=", &tail)) {
2580 // No longer used.
2581 } else if (match_option(option, "-XX:TLESize=", &tail)) {
2582 julong long_tlab_size = 0;
2583 ArgsRange errcode = parse_memory_size(tail, &long_tlab_size, 1);
2584 if (errcode != arg_in_range) {
2585 jio_fprintf(defaultStream::error_stream(),
2586 "Invalid TLAB size: %s\n", option->optionString);
2587 describe_range_error(errcode);
2588 return JNI_EINVAL;
2589 }
2590 FLAG_SET_CMDLINE(uintx, TLABSize, long_tlab_size);
2591 } else if (match_option(option, "-XX:TLEThreadRatio=", &tail)) {
2592 // No longer used.
2593 } else if (match_option(option, "-XX:+UseTLE", &tail)) {
2594 FLAG_SET_CMDLINE(bool, UseTLAB, true);
2595 } else if (match_option(option, "-XX:-UseTLE", &tail)) {
2596 FLAG_SET_CMDLINE(bool, UseTLAB, false);
2597 SOLARIS_ONLY(
2598 } else if (match_option(option, "-XX:+UsePermISM", &tail)) {
2599 warning("-XX:+UsePermISM is obsolete.");
2600 FLAG_SET_CMDLINE(bool, UseISM, true);
2601 } else if (match_option(option, "-XX:-UsePermISM", &tail)) {
2602 FLAG_SET_CMDLINE(bool, UseISM, false);
2603 )
2604 } else if (match_option(option, "-XX:+DisplayVMOutputToStderr", &tail)) {
2605 FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false);
2606 FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true);
2607 } else if (match_option(option, "-XX:+DisplayVMOutputToStdout", &tail)) {
2608 FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false);
2609 FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true);
2610 } else if (match_option(option, "-XX:+ExtendedDTraceProbes", &tail)) {
2611 #if defined(DTRACE_ENABLED)
2612 FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true);
2613 FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true);
2614 FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true);
2615 FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true);
2616 #else // defined(DTRACE_ENABLED)
2617 jio_fprintf(defaultStream::error_stream(),
2618 "ExtendedDTraceProbes flag is not applicable for this configuration\n");
2619 return JNI_EINVAL;
2620 #endif // defined(DTRACE_ENABLED)
2621 #ifdef ASSERT
2622 } else if (match_option(option, "-XX:+FullGCALot", &tail)) {
2623 FLAG_SET_CMDLINE(bool, FullGCALot, true);
2624 // disable scavenge before parallel mark-compact
2625 FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2626 #endif
2627 } else if (match_option(option, "-XX:CMSParPromoteBlocksToClaim=", &tail)) {
2628 julong cms_blocks_to_claim = (julong)atol(tail);
2629 FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2630 jio_fprintf(defaultStream::error_stream(),
2631 "Please use -XX:OldPLABSize in place of "
2632 "-XX:CMSParPromoteBlocksToClaim in the future\n");
2633 } else if (match_option(option, "-XX:ParCMSPromoteBlocksToClaim=", &tail)) {
2634 julong cms_blocks_to_claim = (julong)atol(tail);
2635 FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2636 jio_fprintf(defaultStream::error_stream(),
2637 "Please use -XX:OldPLABSize in place of "
2638 "-XX:ParCMSPromoteBlocksToClaim in the future\n");
2639 } else if (match_option(option, "-XX:ParallelGCOldGenAllocBufferSize=", &tail)) {
2640 julong old_plab_size = 0;
2641 ArgsRange errcode = parse_memory_size(tail, &old_plab_size, 1);
2642 if (errcode != arg_in_range) {
2643 jio_fprintf(defaultStream::error_stream(),
2644 "Invalid old PLAB size: %s\n", option->optionString);
2645 describe_range_error(errcode);
2646 return JNI_EINVAL;
2647 }
2648 FLAG_SET_CMDLINE(uintx, OldPLABSize, old_plab_size);
2649 jio_fprintf(defaultStream::error_stream(),
2650 "Please use -XX:OldPLABSize in place of "
2651 "-XX:ParallelGCOldGenAllocBufferSize in the future\n");
2652 } else if (match_option(option, "-XX:ParallelGCToSpaceAllocBufferSize=", &tail)) {
2653 julong young_plab_size = 0;
2654 ArgsRange errcode = parse_memory_size(tail, &young_plab_size, 1);
2655 if (errcode != arg_in_range) {
2656 jio_fprintf(defaultStream::error_stream(),
2657 "Invalid young PLAB size: %s\n", option->optionString);
2658 describe_range_error(errcode);
2659 return JNI_EINVAL;
2660 }
2661 FLAG_SET_CMDLINE(uintx, YoungPLABSize, young_plab_size);
2662 jio_fprintf(defaultStream::error_stream(),
2663 "Please use -XX:YoungPLABSize in place of "
2664 "-XX:ParallelGCToSpaceAllocBufferSize in the future\n");
2665 } else if (match_option(option, "-XX:CMSMarkStackSize=", &tail) ||
2666 match_option(option, "-XX:G1MarkStackSize=", &tail)) {
2667 julong stack_size = 0;
2668 ArgsRange errcode = parse_memory_size(tail, &stack_size, 1);
2669 if (errcode != arg_in_range) {
2670 jio_fprintf(defaultStream::error_stream(),
2671 "Invalid mark stack size: %s\n", option->optionString);
2672 describe_range_error(errcode);
2673 return JNI_EINVAL;
2674 }
2675 FLAG_SET_CMDLINE(uintx, MarkStackSize, stack_size);
2676 } else if (match_option(option, "-XX:CMSMarkStackSizeMax=", &tail)) {
2677 julong max_stack_size = 0;
2678 ArgsRange errcode = parse_memory_size(tail, &max_stack_size, 1);
2679 if (errcode != arg_in_range) {
2680 jio_fprintf(defaultStream::error_stream(),
2681 "Invalid maximum mark stack size: %s\n",
2682 option->optionString);
2683 describe_range_error(errcode);
2684 return JNI_EINVAL;
2685 }
2686 FLAG_SET_CMDLINE(uintx, MarkStackSizeMax, max_stack_size);
2687 } else if (match_option(option, "-XX:ParallelMarkingThreads=", &tail) ||
2688 match_option(option, "-XX:ParallelCMSThreads=", &tail)) {
2689 uintx conc_threads = 0;
2690 if (!parse_uintx(tail, &conc_threads, 1)) {
2691 jio_fprintf(defaultStream::error_stream(),
2692 "Invalid concurrent threads: %s\n", option->optionString);
2693 return JNI_EINVAL;
2694 }
2695 FLAG_SET_CMDLINE(uintx, ConcGCThreads, conc_threads);
2696 } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
2697 // Skip -XX:Flags= since that case has already been handled
2698 if (strncmp(tail, "Flags=", strlen("Flags=")) != 0) {
2699 if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
2700 return JNI_EINVAL;
2701 }
2702 }
2703 // Unknown option
2704 } else if (is_bad_option(option, args->ignoreUnrecognized)) {
2705 return JNI_ERR;
2706 }
2707 }
2709 // Change the default value for flags which have different default values
2710 // when working with older JDKs.
2711 if (JDK_Version::current().compare_major(6) <= 0 &&
2712 FLAG_IS_DEFAULT(UseVMInterruptibleIO)) {
2713 FLAG_SET_DEFAULT(UseVMInterruptibleIO, true);
2714 }
2715 #ifdef LINUX
2716 if (JDK_Version::current().compare_major(6) <= 0 &&
2717 FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
2718 FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
2719 }
2720 #endif // LINUX
2721 return JNI_OK;
2722 }
2724 jint Arguments::finalize_vm_init_args(SysClassPath* scp_p, bool scp_assembly_required) {
2725 // This must be done after all -D arguments have been processed.
2726 scp_p->expand_endorsed();
2728 if (scp_assembly_required || scp_p->get_endorsed() != NULL) {
2729 // Assemble the bootclasspath elements into the final path.
2730 Arguments::set_sysclasspath(scp_p->combined_path());
2731 }
2733 // This must be done after all arguments have been processed.
2734 // java_compiler() true means set to "NONE" or empty.
2735 if (java_compiler() && !xdebug_mode()) {
2736 // For backwards compatibility, we switch to interpreted mode if
2737 // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
2738 // not specified.
2739 set_mode_flags(_int);
2740 }
2741 if (CompileThreshold == 0) {
2742 set_mode_flags(_int);
2743 }
2745 #ifndef COMPILER2
2746 // Don't degrade server performance for footprint
2747 if (FLAG_IS_DEFAULT(UseLargePages) &&
2748 MaxHeapSize < LargePageHeapSizeThreshold) {
2749 // No need for large granularity pages w/small heaps.
2750 // Note that large pages are enabled/disabled for both the
2751 // Java heap and the code cache.
2752 FLAG_SET_DEFAULT(UseLargePages, false);
2753 SOLARIS_ONLY(FLAG_SET_DEFAULT(UseMPSS, false));
2754 SOLARIS_ONLY(FLAG_SET_DEFAULT(UseISM, false));
2755 }
2757 // Tiered compilation is undefined with C1.
2758 TieredCompilation = false;
2759 #else
2760 if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
2761 FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
2762 }
2763 #endif
2765 // If we are running in a headless jre, force java.awt.headless property
2766 // to be true unless the property has already been set.
2767 // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
2768 if (os::is_headless_jre()) {
2769 const char* headless = Arguments::get_property("java.awt.headless");
2770 if (headless == NULL) {
2771 char envbuffer[128];
2772 if (!os::getenv("JAVA_AWT_HEADLESS", envbuffer, sizeof(envbuffer))) {
2773 if (!add_property("java.awt.headless=true")) {
2774 return JNI_ENOMEM;
2775 }
2776 } else {
2777 char buffer[256];
2778 strcpy(buffer, "java.awt.headless=");
2779 strcat(buffer, envbuffer);
2780 if (!add_property(buffer)) {
2781 return JNI_ENOMEM;
2782 }
2783 }
2784 }
2785 }
2787 if (!check_vm_args_consistency()) {
2788 return JNI_ERR;
2789 }
2791 return JNI_OK;
2792 }
2794 jint Arguments::parse_java_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2795 return parse_options_environment_variable("_JAVA_OPTIONS", scp_p,
2796 scp_assembly_required_p);
2797 }
2799 jint Arguments::parse_java_tool_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2800 return parse_options_environment_variable("JAVA_TOOL_OPTIONS", scp_p,
2801 scp_assembly_required_p);
2802 }
2804 jint Arguments::parse_options_environment_variable(const char* name, SysClassPath* scp_p, bool* scp_assembly_required_p) {
2805 const int N_MAX_OPTIONS = 64;
2806 const int OPTION_BUFFER_SIZE = 1024;
2807 char buffer[OPTION_BUFFER_SIZE];
2809 // The variable will be ignored if it exceeds the length of the buffer.
2810 // Don't check this variable if user has special privileges
2811 // (e.g. unix su command).
2812 if (os::getenv(name, buffer, sizeof(buffer)) &&
2813 !os::have_special_privileges()) {
2814 JavaVMOption options[N_MAX_OPTIONS]; // Construct option array
2815 jio_fprintf(defaultStream::error_stream(),
2816 "Picked up %s: %s\n", name, buffer);
2817 char* rd = buffer; // pointer to the input string (rd)
2818 int i;
2819 for (i = 0; i < N_MAX_OPTIONS;) { // repeat for all options in the input string
2820 while (isspace(*rd)) rd++; // skip whitespace
2821 if (*rd == 0) break; // we re done when the input string is read completely
2823 // The output, option string, overwrites the input string.
2824 // Because of quoting, the pointer to the option string (wrt) may lag the pointer to
2825 // input string (rd).
2826 char* wrt = rd;
2828 options[i++].optionString = wrt; // Fill in option
2829 while (*rd != 0 && !isspace(*rd)) { // unquoted strings terminate with a space or NULL
2830 if (*rd == '\'' || *rd == '"') { // handle a quoted string
2831 int quote = *rd; // matching quote to look for
2832 rd++; // don't copy open quote
2833 while (*rd != quote) { // include everything (even spaces) up until quote
2834 if (*rd == 0) { // string termination means unmatched string
2835 jio_fprintf(defaultStream::error_stream(),
2836 "Unmatched quote in %s\n", name);
2837 return JNI_ERR;
2838 }
2839 *wrt++ = *rd++; // copy to option string
2840 }
2841 rd++; // don't copy close quote
2842 } else {
2843 *wrt++ = *rd++; // copy to option string
2844 }
2845 }
2846 // Need to check if we're done before writing a NULL,
2847 // because the write could be to the byte that rd is pointing to.
2848 if (*rd++ == 0) {
2849 *wrt = 0;
2850 break;
2851 }
2852 *wrt = 0; // Zero terminate option
2853 }
2854 // Construct JavaVMInitArgs structure and parse as if it was part of the command line
2855 JavaVMInitArgs vm_args;
2856 vm_args.version = JNI_VERSION_1_2;
2857 vm_args.options = options;
2858 vm_args.nOptions = i;
2859 vm_args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
2861 if (PrintVMOptions) {
2862 const char* tail;
2863 for (int i = 0; i < vm_args.nOptions; i++) {
2864 const JavaVMOption *option = vm_args.options + i;
2865 if (match_option(option, "-XX:", &tail)) {
2866 logOption(tail);
2867 }
2868 }
2869 }
2871 return(parse_each_vm_init_arg(&vm_args, scp_p, scp_assembly_required_p, ENVIRON_VAR));
2872 }
2873 return JNI_OK;
2874 }
2876 void Arguments::set_shared_spaces_flags() {
2877 const bool must_share = DumpSharedSpaces || RequireSharedSpaces;
2878 const bool might_share = must_share || UseSharedSpaces;
2880 // The string table is part of the shared archive so the size must match.
2881 if (!FLAG_IS_DEFAULT(StringTableSize)) {
2882 // Disable sharing.
2883 if (must_share) {
2884 warning("disabling shared archive %s because of non-default "
2885 "StringTableSize", DumpSharedSpaces ? "creation" : "use");
2886 }
2887 if (might_share) {
2888 FLAG_SET_DEFAULT(DumpSharedSpaces, false);
2889 FLAG_SET_DEFAULT(RequireSharedSpaces, false);
2890 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2891 }
2892 return;
2893 }
2895 // Check whether class data sharing settings conflict with GC, compressed oops
2896 // or page size, and fix them up. Explicit sharing options override other
2897 // settings.
2898 const bool cannot_share = UseConcMarkSweepGC || CMSIncrementalMode ||
2899 UseG1GC || UseParNewGC || UseParallelGC || UseParallelOldGC ||
2900 UseCompressedOops || UseLargePages && FLAG_IS_CMDLINE(UseLargePages);
2901 if (cannot_share) {
2902 if (must_share) {
2903 warning("selecting serial gc and disabling large pages %s"
2904 "because of %s", "" LP64_ONLY("and compressed oops "),
2905 DumpSharedSpaces ? "-Xshare:dump" : "-Xshare:on");
2906 force_serial_gc();
2907 FLAG_SET_CMDLINE(bool, UseLargePages, false);
2908 LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedOops, false));
2909 } else {
2910 if (UseSharedSpaces && Verbose) {
2911 warning("turning off use of shared archive because of "
2912 "choice of garbage collector or large pages");
2913 }
2914 no_shared_spaces();
2915 }
2916 } else if (UseLargePages && might_share) {
2917 // Disable large pages to allow shared spaces. This is sub-optimal, since
2918 // there may not even be a shared archive to use.
2919 FLAG_SET_DEFAULT(UseLargePages, false);
2920 }
2921 }
2923 // Disable options not supported in this release, with a warning if they
2924 // were explicitly requested on the command-line
2925 #define UNSUPPORTED_OPTION(opt, description) \
2926 do { \
2927 if (opt) { \
2928 if (FLAG_IS_CMDLINE(opt)) { \
2929 warning(description " is disabled in this release."); \
2930 } \
2931 FLAG_SET_DEFAULT(opt, false); \
2932 } \
2933 } while(0)
2935 // Parse entry point called from JNI_CreateJavaVM
2937 jint Arguments::parse(const JavaVMInitArgs* args) {
2939 // Sharing support
2940 // Construct the path to the archive
2941 char jvm_path[JVM_MAXPATHLEN];
2942 os::jvm_path(jvm_path, sizeof(jvm_path));
2943 #ifdef TIERED
2944 if (strstr(jvm_path, "client") != NULL) {
2945 force_client_mode = true;
2946 }
2947 #endif // TIERED
2948 char *end = strrchr(jvm_path, *os::file_separator());
2949 if (end != NULL) *end = '\0';
2950 char *shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(jvm_path) +
2951 strlen(os::file_separator()) + 20);
2952 if (shared_archive_path == NULL) return JNI_ENOMEM;
2953 strcpy(shared_archive_path, jvm_path);
2954 strcat(shared_archive_path, os::file_separator());
2955 strcat(shared_archive_path, "classes");
2956 DEBUG_ONLY(strcat(shared_archive_path, "_g");)
2957 strcat(shared_archive_path, ".jsa");
2958 SharedArchivePath = shared_archive_path;
2960 // Remaining part of option string
2961 const char* tail;
2963 // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
2964 bool settings_file_specified = false;
2965 const char* flags_file;
2966 int index;
2967 for (index = 0; index < args->nOptions; index++) {
2968 const JavaVMOption *option = args->options + index;
2969 if (match_option(option, "-XX:Flags=", &tail)) {
2970 flags_file = tail;
2971 settings_file_specified = true;
2972 }
2973 if (match_option(option, "-XX:+PrintVMOptions", &tail)) {
2974 PrintVMOptions = true;
2975 }
2976 if (match_option(option, "-XX:-PrintVMOptions", &tail)) {
2977 PrintVMOptions = false;
2978 }
2979 if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions", &tail)) {
2980 IgnoreUnrecognizedVMOptions = true;
2981 }
2982 if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions", &tail)) {
2983 IgnoreUnrecognizedVMOptions = false;
2984 }
2985 if (match_option(option, "-XX:+PrintFlagsInitial", &tail)) {
2986 CommandLineFlags::printFlags(tty, false);
2987 vm_exit(0);
2988 }
2990 #ifndef PRODUCT
2991 if (match_option(option, "-XX:+PrintFlagsWithComments", &tail)) {
2992 CommandLineFlags::printFlags(tty, true);
2993 vm_exit(0);
2994 }
2995 #endif
2996 }
2998 if (IgnoreUnrecognizedVMOptions) {
2999 // uncast const to modify the flag args->ignoreUnrecognized
3000 *(jboolean*)(&args->ignoreUnrecognized) = true;
3001 }
3003 // Parse specified settings file
3004 if (settings_file_specified) {
3005 if (!process_settings_file(flags_file, true, args->ignoreUnrecognized)) {
3006 return JNI_EINVAL;
3007 }
3008 }
3010 // Parse default .hotspotrc settings file
3011 if (!settings_file_specified) {
3012 if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
3013 return JNI_EINVAL;
3014 }
3015 }
3017 if (PrintVMOptions) {
3018 for (index = 0; index < args->nOptions; index++) {
3019 const JavaVMOption *option = args->options + index;
3020 if (match_option(option, "-XX:", &tail)) {
3021 logOption(tail);
3022 }
3023 }
3024 }
3026 // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
3027 jint result = parse_vm_init_args(args);
3028 if (result != JNI_OK) {
3029 return result;
3030 }
3032 #ifdef JAVASE_EMBEDDED
3033 UNSUPPORTED_OPTION(UseG1GC, "G1 GC");
3034 #endif
3036 #ifndef PRODUCT
3037 if (TraceBytecodesAt != 0) {
3038 TraceBytecodes = true;
3039 }
3040 if (CountCompiledCalls) {
3041 if (UseCounterDecay) {
3042 warning("UseCounterDecay disabled because CountCalls is set");
3043 UseCounterDecay = false;
3044 }
3045 }
3046 #endif // PRODUCT
3048 // Transitional
3049 if (EnableMethodHandles || AnonymousClasses) {
3050 if (!EnableInvokeDynamic && !FLAG_IS_DEFAULT(EnableInvokeDynamic)) {
3051 warning("EnableMethodHandles and AnonymousClasses are obsolete. Keeping EnableInvokeDynamic disabled.");
3052 } else {
3053 EnableInvokeDynamic = true;
3054 }
3055 }
3057 // JSR 292 is not supported before 1.7
3058 if (!JDK_Version::is_gte_jdk17x_version()) {
3059 if (EnableInvokeDynamic) {
3060 if (!FLAG_IS_DEFAULT(EnableInvokeDynamic)) {
3061 warning("JSR 292 is not supported before 1.7. Disabling support.");
3062 }
3063 EnableInvokeDynamic = false;
3064 }
3065 }
3067 if (EnableInvokeDynamic && ScavengeRootsInCode == 0) {
3068 if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3069 warning("forcing ScavengeRootsInCode non-zero because EnableInvokeDynamic is true");
3070 }
3071 ScavengeRootsInCode = 1;
3072 }
3073 if (!JavaObjectsInPerm && ScavengeRootsInCode == 0) {
3074 if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3075 warning("forcing ScavengeRootsInCode non-zero because JavaObjectsInPerm is false");
3076 }
3077 ScavengeRootsInCode = 1;
3078 }
3080 if (PrintGCDetails) {
3081 // Turn on -verbose:gc options as well
3082 PrintGC = true;
3083 }
3085 // Set object alignment values.
3086 set_object_alignment();
3088 #ifdef SERIALGC
3089 force_serial_gc();
3090 #endif // SERIALGC
3091 #ifdef KERNEL
3092 no_shared_spaces();
3093 #endif // KERNEL
3095 // Set flags based on ergonomics.
3096 set_ergonomics_flags();
3098 set_shared_spaces_flags();
3100 // Check the GC selections again.
3101 if (!check_gc_consistency()) {
3102 return JNI_EINVAL;
3103 }
3105 if (TieredCompilation) {
3106 set_tiered_flags();
3107 } else {
3108 // Check if the policy is valid. Policies 0 and 1 are valid for non-tiered setup.
3109 if (CompilationPolicyChoice >= 2) {
3110 vm_exit_during_initialization(
3111 "Incompatible compilation policy selected", NULL);
3112 }
3113 }
3115 #ifndef KERNEL
3116 // Set heap size based on available physical memory
3117 set_heap_size();
3118 // Set per-collector flags
3119 if (UseParallelGC || UseParallelOldGC) {
3120 set_parallel_gc_flags();
3121 } else if (UseConcMarkSweepGC) { // should be done before ParNew check below
3122 set_cms_and_parnew_gc_flags();
3123 } else if (UseParNewGC) { // skipped if CMS is set above
3124 set_parnew_gc_flags();
3125 } else if (UseG1GC) {
3126 set_g1_gc_flags();
3127 }
3128 #endif // KERNEL
3130 #ifdef SERIALGC
3131 assert(verify_serial_gc_flags(), "SerialGC unset");
3132 #endif // SERIALGC
3134 // Set bytecode rewriting flags
3135 set_bytecode_flags();
3137 // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled.
3138 set_aggressive_opts_flags();
3140 // Turn off biased locking for locking debug mode flags,
3141 // which are subtlely different from each other but neither works with
3142 // biased locking.
3143 if (UseHeavyMonitors
3144 #ifdef COMPILER1
3145 || !UseFastLocking
3146 #endif // COMPILER1
3147 ) {
3148 if (!FLAG_IS_DEFAULT(UseBiasedLocking) && UseBiasedLocking) {
3149 // flag set to true on command line; warn the user that they
3150 // can't enable biased locking here
3151 warning("Biased Locking is not supported with locking debug flags"
3152 "; ignoring UseBiasedLocking flag." );
3153 }
3154 UseBiasedLocking = false;
3155 }
3157 #ifdef CC_INTERP
3158 // Clear flags not supported by the C++ interpreter
3159 FLAG_SET_DEFAULT(ProfileInterpreter, false);
3160 FLAG_SET_DEFAULT(UseBiasedLocking, false);
3161 LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
3162 #endif // CC_INTERP
3164 #ifdef COMPILER2
3165 if (!UseBiasedLocking || EmitSync != 0) {
3166 UseOptoBiasInlining = false;
3167 }
3168 if (!EliminateLocks) {
3169 EliminateNestedLocks = false;
3170 }
3171 #endif
3173 if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
3174 warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
3175 DebugNonSafepoints = true;
3176 }
3178 #ifndef PRODUCT
3179 if (CompileTheWorld) {
3180 // Force NmethodSweeper to sweep whole CodeCache each time.
3181 if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
3182 NmethodSweepFraction = 1;
3183 }
3184 }
3185 #endif
3187 if (PrintCommandLineFlags) {
3188 CommandLineFlags::printSetFlags(tty);
3189 }
3191 // Apply CPU specific policy for the BiasedLocking
3192 if (UseBiasedLocking) {
3193 if (!VM_Version::use_biased_locking() &&
3194 !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
3195 UseBiasedLocking = false;
3196 }
3197 }
3199 // set PauseAtExit if the gamma launcher was used and a debugger is attached
3200 // but only if not already set on the commandline
3201 if (Arguments::created_by_gamma_launcher() && os::is_debugger_attached()) {
3202 bool set = false;
3203 CommandLineFlags::wasSetOnCmdline("PauseAtExit", &set);
3204 if (!set) {
3205 FLAG_SET_DEFAULT(PauseAtExit, true);
3206 }
3207 }
3209 return JNI_OK;
3210 }
3212 int Arguments::PropertyList_count(SystemProperty* pl) {
3213 int count = 0;
3214 while(pl != NULL) {
3215 count++;
3216 pl = pl->next();
3217 }
3218 return count;
3219 }
3221 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
3222 assert(key != NULL, "just checking");
3223 SystemProperty* prop;
3224 for (prop = pl; prop != NULL; prop = prop->next()) {
3225 if (strcmp(key, prop->key()) == 0) return prop->value();
3226 }
3227 return NULL;
3228 }
3230 const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
3231 int count = 0;
3232 const char* ret_val = NULL;
3234 while(pl != NULL) {
3235 if(count >= index) {
3236 ret_val = pl->key();
3237 break;
3238 }
3239 count++;
3240 pl = pl->next();
3241 }
3243 return ret_val;
3244 }
3246 char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
3247 int count = 0;
3248 char* ret_val = NULL;
3250 while(pl != NULL) {
3251 if(count >= index) {
3252 ret_val = pl->value();
3253 break;
3254 }
3255 count++;
3256 pl = pl->next();
3257 }
3259 return ret_val;
3260 }
3262 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
3263 SystemProperty* p = *plist;
3264 if (p == NULL) {
3265 *plist = new_p;
3266 } else {
3267 while (p->next() != NULL) {
3268 p = p->next();
3269 }
3270 p->set_next(new_p);
3271 }
3272 }
3274 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, char* v) {
3275 if (plist == NULL)
3276 return;
3278 SystemProperty* new_p = new SystemProperty(k, v, true);
3279 PropertyList_add(plist, new_p);
3280 }
3282 // This add maintains unique property key in the list.
3283 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, char* v, jboolean append) {
3284 if (plist == NULL)
3285 return;
3287 // If property key exist then update with new value.
3288 SystemProperty* prop;
3289 for (prop = *plist; prop != NULL; prop = prop->next()) {
3290 if (strcmp(k, prop->key()) == 0) {
3291 if (append) {
3292 prop->append_value(v);
3293 } else {
3294 prop->set_value(v);
3295 }
3296 return;
3297 }
3298 }
3300 PropertyList_add(plist, k, v);
3301 }
3303 #ifdef KERNEL
3304 char *Arguments::get_kernel_properties() {
3305 // Find properties starting with kernel and append them to string
3306 // We need to find out how long they are first because the URL's that they
3307 // might point to could get long.
3308 int length = 0;
3309 SystemProperty* prop;
3310 for (prop = _system_properties; prop != NULL; prop = prop->next()) {
3311 if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
3312 length += (strlen(prop->key()) + strlen(prop->value()) + 5); // "-D ="
3313 }
3314 }
3315 // Add one for null terminator.
3316 char *props = AllocateHeap(length + 1, "get_kernel_properties");
3317 if (length != 0) {
3318 int pos = 0;
3319 for (prop = _system_properties; prop != NULL; prop = prop->next()) {
3320 if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
3321 jio_snprintf(&props[pos], length-pos,
3322 "-D%s=%s ", prop->key(), prop->value());
3323 pos = strlen(props);
3324 }
3325 }
3326 }
3327 // null terminate props in case of null
3328 props[length] = '\0';
3329 return props;
3330 }
3331 #endif // KERNEL
3333 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
3334 // Returns true if all of the source pointed by src has been copied over to
3335 // the destination buffer pointed by buf. Otherwise, returns false.
3336 // Notes:
3337 // 1. If the length (buflen) of the destination buffer excluding the
3338 // NULL terminator character is not long enough for holding the expanded
3339 // pid characters, it also returns false instead of returning the partially
3340 // expanded one.
3341 // 2. The passed in "buflen" should be large enough to hold the null terminator.
3342 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
3343 char* buf, size_t buflen) {
3344 const char* p = src;
3345 char* b = buf;
3346 const char* src_end = &src[srclen];
3347 char* buf_end = &buf[buflen - 1];
3349 while (p < src_end && b < buf_end) {
3350 if (*p == '%') {
3351 switch (*(++p)) {
3352 case '%': // "%%" ==> "%"
3353 *b++ = *p++;
3354 break;
3355 case 'p': { // "%p" ==> current process id
3356 // buf_end points to the character before the last character so
3357 // that we could write '\0' to the end of the buffer.
3358 size_t buf_sz = buf_end - b + 1;
3359 int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
3361 // if jio_snprintf fails or the buffer is not long enough to hold
3362 // the expanded pid, returns false.
3363 if (ret < 0 || ret >= (int)buf_sz) {
3364 return false;
3365 } else {
3366 b += ret;
3367 assert(*b == '\0', "fail in copy_expand_pid");
3368 if (p == src_end && b == buf_end + 1) {
3369 // reach the end of the buffer.
3370 return true;
3371 }
3372 }
3373 p++;
3374 break;
3375 }
3376 default :
3377 *b++ = '%';
3378 }
3379 } else {
3380 *b++ = *p++;
3381 }
3382 }
3383 *b = '\0';
3384 return (p == src_end); // return false if not all of the source was copied
3385 }