1 /* 2 * Copyright (c) 1997, 2018, 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 */ 24 25 #include "precompiled.hpp" 26 #include "jvm.h" 27 #include "classfile/classLoader.hpp" 28 #include "classfile/javaClasses.hpp" 29 #include "classfile/moduleEntry.hpp" 30 #include "classfile/systemDictionary.hpp" 31 #include "classfile/vmSymbols.hpp" 32 #include "code/codeCache.hpp" 33 #include "code/icBuffer.hpp" 34 #include "code/vtableStubs.hpp" 35 #include "gc/shared/vmGCOperations.hpp" 36 #include "logging/log.hpp" 37 #include "interpreter/interpreter.hpp" 38 #include "logging/log.hpp" 39 #include "logging/logStream.hpp" 40 #include "memory/allocation.inline.hpp" 41 #ifdef ASSERT 42 #include "memory/guardedMemory.hpp" 43 #endif 44 #include "memory/resourceArea.hpp" 45 #include "oops/oop.inline.hpp" 46 #include "prims/jvm_misc.hpp" 47 #include "prims/privilegedStack.hpp" 48 #include "runtime/arguments.hpp" 49 #include "runtime/atomic.hpp" 50 #include "runtime/frame.inline.hpp" 51 #include "runtime/interfaceSupport.inline.hpp" 52 #include "runtime/java.hpp" 53 #include "runtime/javaCalls.hpp" 54 #include "runtime/mutexLocker.hpp" 55 #include "runtime/os.inline.hpp" 56 #include "runtime/sharedRuntime.hpp" 57 #include "runtime/stubRoutines.hpp" 58 #include "runtime/thread.inline.hpp" 59 #include "runtime/threadSMR.hpp" 60 #include "runtime/vm_version.hpp" 61 #include "services/attachListener.hpp" 62 #include "services/mallocTracker.hpp" 63 #include "services/memTracker.hpp" 64 #include "services/nmtCommon.hpp" 65 #include "services/threadService.hpp" 66 #include "utilities/align.hpp" 67 #include "utilities/defaultStream.hpp" 68 #include "utilities/events.hpp" 69 70 # include <signal.h> 71 # include <errno.h> 72 73 OSThread* os::_starting_thread = NULL; 74 address os::_polling_page = NULL; 75 volatile int32_t* os::_mem_serialize_page = NULL; 76 uintptr_t os::_serialize_page_mask = 0; 77 volatile unsigned int os::_rand_seed = 1; 78 int os::_processor_count = 0; 79 int os::_initial_active_processor_count = 0; 80 size_t os::_page_sizes[os::page_sizes_max]; 81 82 #ifndef PRODUCT 83 julong os::num_mallocs = 0; // # of calls to malloc/realloc 84 julong os::alloc_bytes = 0; // # of bytes allocated 85 julong os::num_frees = 0; // # of calls to free 86 julong os::free_bytes = 0; // # of bytes freed 87 #endif 88 89 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords 90 91 void os_init_globals() { 92 // Called from init_globals(). 93 // See Threads::create_vm() in thread.cpp, and init.cpp. 94 os::init_globals(); 95 } 96 97 static time_t get_timezone(const struct tm* time_struct) { 98 #if defined(_ALLBSD_SOURCE) 99 return time_struct->tm_gmtoff; 100 #elif defined(_WINDOWS) 101 long zone; 102 _get_timezone(&zone); 103 return static_cast<time_t>(zone); 104 #else 105 return timezone; 106 #endif 107 } 108 109 int os::snprintf(char* buf, size_t len, const char* fmt, ...) { 110 va_list args; 111 va_start(args, fmt); 112 int result = os::vsnprintf(buf, len, fmt, args); 113 va_end(args); 114 return result; 115 } 116 117 // Fill in buffer with current local time as an ISO-8601 string. 118 // E.g., yyyy-mm-ddThh:mm:ss-zzzz. 119 // Returns buffer, or NULL if it failed. 120 // This would mostly be a call to 121 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 122 // except that on Windows the %z behaves badly, so we do it ourselves. 123 // Also, people wanted milliseconds on there, 124 // and strftime doesn't do milliseconds. 125 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) { 126 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 127 // 1 2 128 // 12345678901234567890123456789 129 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d" 130 static const size_t needed_buffer = 29; 131 132 // Sanity check the arguments 133 if (buffer == NULL) { 134 assert(false, "NULL buffer"); 135 return NULL; 136 } 137 if (buffer_length < needed_buffer) { 138 assert(false, "buffer_length too small"); 139 return NULL; 140 } 141 // Get the current time 142 jlong milliseconds_since_19700101 = javaTimeMillis(); 143 const int milliseconds_per_microsecond = 1000; 144 const time_t seconds_since_19700101 = 145 milliseconds_since_19700101 / milliseconds_per_microsecond; 146 const int milliseconds_after_second = 147 milliseconds_since_19700101 % milliseconds_per_microsecond; 148 // Convert the time value to a tm and timezone variable 149 struct tm time_struct; 150 if (utc) { 151 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 152 assert(false, "Failed gmtime_pd"); 153 return NULL; 154 } 155 } else { 156 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 157 assert(false, "Failed localtime_pd"); 158 return NULL; 159 } 160 } 161 const time_t zone = get_timezone(&time_struct); 162 163 // If daylight savings time is in effect, 164 // we are 1 hour East of our time zone 165 const time_t seconds_per_minute = 60; 166 const time_t minutes_per_hour = 60; 167 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 168 time_t UTC_to_local = zone; 169 if (time_struct.tm_isdst > 0) { 170 UTC_to_local = UTC_to_local - seconds_per_hour; 171 } 172 173 // No offset when dealing with UTC 174 if (utc) { 175 UTC_to_local = 0; 176 } 177 178 // Compute the time zone offset. 179 // localtime_pd() sets timezone to the difference (in seconds) 180 // between UTC and and local time. 181 // ISO 8601 says we need the difference between local time and UTC, 182 // we change the sign of the localtime_pd() result. 183 const time_t local_to_UTC = -(UTC_to_local); 184 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 185 char sign_local_to_UTC = '+'; 186 time_t abs_local_to_UTC = local_to_UTC; 187 if (local_to_UTC < 0) { 188 sign_local_to_UTC = '-'; 189 abs_local_to_UTC = -(abs_local_to_UTC); 190 } 191 // Convert time zone offset seconds to hours and minutes. 192 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 193 const time_t zone_min = 194 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 195 196 // Print an ISO 8601 date and time stamp into the buffer 197 const int year = 1900 + time_struct.tm_year; 198 const int month = 1 + time_struct.tm_mon; 199 const int printed = jio_snprintf(buffer, buffer_length, 200 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d", 201 year, 202 month, 203 time_struct.tm_mday, 204 time_struct.tm_hour, 205 time_struct.tm_min, 206 time_struct.tm_sec, 207 milliseconds_after_second, 208 sign_local_to_UTC, 209 zone_hours, 210 zone_min); 211 if (printed == 0) { 212 assert(false, "Failed jio_printf"); 213 return NULL; 214 } 215 return buffer; 216 } 217 218 OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 219 debug_only(Thread::check_for_dangling_thread_pointer(thread);) 220 221 if (p >= MinPriority && p <= MaxPriority) { 222 int priority = java_to_os_priority[p]; 223 return set_native_priority(thread, priority); 224 } else { 225 assert(false, "Should not happen"); 226 return OS_ERR; 227 } 228 } 229 230 // The mapping from OS priority back to Java priority may be inexact because 231 // Java priorities can map M:1 with native priorities. If you want the definite 232 // Java priority then use JavaThread::java_priority() 233 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 234 int p; 235 int os_prio; 236 OSReturn ret = get_native_priority(thread, &os_prio); 237 if (ret != OS_OK) return ret; 238 239 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 240 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 241 } else { 242 // niceness values are in reverse order 243 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 244 } 245 priority = (ThreadPriority)p; 246 return OS_OK; 247 } 248 249 bool os::dll_build_name(char* buffer, size_t size, const char* fname) { 250 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX); 251 return (n != -1); 252 } 253 254 #if !defined(LINUX) && !defined(_WINDOWS) 255 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) { 256 committed_start = start; 257 committed_size = size; 258 return true; 259 } 260 #endif 261 262 // Helper for dll_locate_lib. 263 // Pass buffer and printbuffer as we already printed the path to buffer 264 // when we called get_current_directory. This way we avoid another buffer 265 // of size MAX_PATH. 266 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen, 267 const char* pname, char lastchar, const char* fname) { 268 269 // Concatenate path and file name, but don't print double path separators. 270 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ? 271 "" : os::file_separator(); 272 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname); 273 // Check whether file exists. 274 if (ret != -1) { 275 struct stat statbuf; 276 return os::stat(buffer, &statbuf) == 0; 277 } 278 return false; 279 } 280 281 bool os::dll_locate_lib(char *buffer, size_t buflen, 282 const char* pname, const char* fname) { 283 bool retval = false; 284 285 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX); 286 char* fullfname = (char*)NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal); 287 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) { 288 const size_t pnamelen = pname ? strlen(pname) : 0; 289 290 if (pnamelen == 0) { 291 // If no path given, use current working directory. 292 const char* p = get_current_directory(buffer, buflen); 293 if (p != NULL) { 294 const size_t plen = strlen(buffer); 295 const char lastchar = buffer[plen - 1]; 296 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen, 297 "", lastchar, fullfname); 298 } 299 } else if (strchr(pname, *os::path_separator()) != NULL) { 300 // A list of paths. Search for the path that contains the library. 301 int n; 302 char** pelements = split_path(pname, &n); 303 if (pelements != NULL) { 304 for (int i = 0; i < n; i++) { 305 char* path = pelements[i]; 306 // Really shouldn't be NULL, but check can't hurt. 307 size_t plen = (path == NULL) ? 0 : strlen(path); 308 if (plen == 0) { 309 continue; // Skip the empty path values. 310 } 311 const char lastchar = path[plen - 1]; 312 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname); 313 if (retval) break; 314 } 315 // Release the storage allocated by split_path. 316 for (int i = 0; i < n; i++) { 317 if (pelements[i] != NULL) { 318 FREE_C_HEAP_ARRAY(char, pelements[i]); 319 } 320 } 321 FREE_C_HEAP_ARRAY(char*, pelements); 322 } 323 } else { 324 // A definite path. 325 const char lastchar = pname[pnamelen-1]; 326 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname); 327 } 328 } 329 330 FREE_C_HEAP_ARRAY(char*, fullfname); 331 return retval; 332 } 333 334 // --------------------- sun.misc.Signal (optional) --------------------- 335 336 337 // SIGBREAK is sent by the keyboard to query the VM state 338 #ifndef SIGBREAK 339 #define SIGBREAK SIGQUIT 340 #endif 341 342 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 343 344 345 static void signal_thread_entry(JavaThread* thread, TRAPS) { 346 os::set_priority(thread, NearMaxPriority); 347 while (true) { 348 int sig; 349 { 350 // FIXME : Currently we have not decided what should be the status 351 // for this java thread blocked here. Once we decide about 352 // that we should fix this. 353 sig = os::signal_wait(); 354 } 355 if (sig == os::sigexitnum_pd()) { 356 // Terminate the signal thread 357 return; 358 } 359 360 switch (sig) { 361 case SIGBREAK: { 362 // Check if the signal is a trigger to start the Attach Listener - in that 363 // case don't print stack traces. 364 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 365 continue; 366 } 367 // Print stack traces 368 // Any SIGBREAK operations added here should make sure to flush 369 // the output stream (e.g. tty->flush()) after output. See 4803766. 370 // Each module also prints an extra carriage return after its output. 371 VM_PrintThreads op; 372 VMThread::execute(&op); 373 VM_PrintJNI jni_op; 374 VMThread::execute(&jni_op); 375 VM_FindDeadlocks op1(tty); 376 VMThread::execute(&op1); 377 Universe::print_heap_at_SIGBREAK(); 378 if (PrintClassHistogram) { 379 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */); 380 VMThread::execute(&op1); 381 } 382 if (JvmtiExport::should_post_data_dump()) { 383 JvmtiExport::post_data_dump(); 384 } 385 break; 386 } 387 default: { 388 // Dispatch the signal to java 389 HandleMark hm(THREAD); 390 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD); 391 if (klass != NULL) { 392 JavaValue result(T_VOID); 393 JavaCallArguments args; 394 args.push_int(sig); 395 JavaCalls::call_static( 396 &result, 397 klass, 398 vmSymbols::dispatch_name(), 399 vmSymbols::int_void_signature(), 400 &args, 401 THREAD 402 ); 403 } 404 if (HAS_PENDING_EXCEPTION) { 405 // tty is initialized early so we don't expect it to be null, but 406 // if it is we can't risk doing an initialization that might 407 // trigger additional out-of-memory conditions 408 if (tty != NULL) { 409 char klass_name[256]; 410 char tmp_sig_name[16]; 411 const char* sig_name = "UNKNOWN"; 412 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 413 name()->as_klass_external_name(klass_name, 256); 414 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 415 sig_name = tmp_sig_name; 416 warning("Exception %s occurred dispatching signal %s to handler" 417 "- the VM may need to be forcibly terminated", 418 klass_name, sig_name ); 419 } 420 CLEAR_PENDING_EXCEPTION; 421 } 422 } 423 } 424 } 425 } 426 427 void os::init_before_ergo() { 428 initialize_initial_active_processor_count(); 429 // We need to initialize large page support here because ergonomics takes some 430 // decisions depending on large page support and the calculated large page size. 431 large_page_init(); 432 433 // We need to adapt the configured number of stack protection pages given 434 // in 4K pages to the actual os page size. We must do this before setting 435 // up minimal stack sizes etc. in os::init_2(). 436 JavaThread::set_stack_red_zone_size (align_up(StackRedPages * 4 * K, vm_page_size())); 437 JavaThread::set_stack_yellow_zone_size (align_up(StackYellowPages * 4 * K, vm_page_size())); 438 JavaThread::set_stack_reserved_zone_size(align_up(StackReservedPages * 4 * K, vm_page_size())); 439 JavaThread::set_stack_shadow_zone_size (align_up(StackShadowPages * 4 * K, vm_page_size())); 440 441 // VM version initialization identifies some characteristics of the 442 // platform that are used during ergonomic decisions. 443 VM_Version::init_before_ergo(); 444 } 445 446 void os::initialize_jdk_signal_support(TRAPS) { 447 if (!ReduceSignalUsage) { 448 // Setup JavaThread for processing signals 449 const char thread_name[] = "Signal Dispatcher"; 450 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 451 452 // Initialize thread_oop to put it into the system threadGroup 453 Handle thread_group (THREAD, Universe::system_thread_group()); 454 Handle thread_oop = JavaCalls::construct_new_instance(SystemDictionary::Thread_klass(), 455 vmSymbols::threadgroup_string_void_signature(), 456 thread_group, 457 string, 458 CHECK); 459 460 Klass* group = SystemDictionary::ThreadGroup_klass(); 461 JavaValue result(T_VOID); 462 JavaCalls::call_special(&result, 463 thread_group, 464 group, 465 vmSymbols::add_method_name(), 466 vmSymbols::thread_void_signature(), 467 thread_oop, 468 CHECK); 469 470 { MutexLocker mu(Threads_lock); 471 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 472 473 // At this point it may be possible that no osthread was created for the 474 // JavaThread due to lack of memory. We would have to throw an exception 475 // in that case. However, since this must work and we do not allow 476 // exceptions anyway, check and abort if this fails. 477 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 478 vm_exit_during_initialization("java.lang.OutOfMemoryError", 479 os::native_thread_creation_failed_msg()); 480 } 481 482 java_lang_Thread::set_thread(thread_oop(), signal_thread); 483 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 484 java_lang_Thread::set_daemon(thread_oop()); 485 486 signal_thread->set_threadObj(thread_oop()); 487 Threads::add(signal_thread); 488 Thread::start(signal_thread); 489 } 490 // Handle ^BREAK 491 os::signal(SIGBREAK, os::user_handler()); 492 } 493 } 494 495 496 void os::terminate_signal_thread() { 497 if (!ReduceSignalUsage) 498 signal_notify(sigexitnum_pd()); 499 } 500 501 502 // --------------------- loading libraries --------------------- 503 504 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 505 extern struct JavaVM_ main_vm; 506 507 static void* _native_java_library = NULL; 508 509 void* os::native_java_library() { 510 if (_native_java_library == NULL) { 511 char buffer[JVM_MAXPATHLEN]; 512 char ebuf[1024]; 513 514 // Try to load verify dll first. In 1.3 java dll depends on it and is not 515 // always able to find it when the loading executable is outside the JDK. 516 // In order to keep working with 1.2 we ignore any loading errors. 517 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(), 518 "verify")) { 519 dll_load(buffer, ebuf, sizeof(ebuf)); 520 } 521 522 // Load java dll 523 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(), 524 "java")) { 525 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 526 } 527 if (_native_java_library == NULL) { 528 vm_exit_during_initialization("Unable to load native library", ebuf); 529 } 530 531 #if defined(__OpenBSD__) 532 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 533 // ignore errors 534 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(), 535 "net")) { 536 dll_load(buffer, ebuf, sizeof(ebuf)); 537 } 538 #endif 539 } 540 return _native_java_library; 541 } 542 543 /* 544 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 545 * If check_lib == true then we are looking for an 546 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 547 * this library is statically linked into the image. 548 * If check_lib == false then we will look for the appropriate symbol in the 549 * executable if agent_lib->is_static_lib() == true or in the shared library 550 * referenced by 'handle'. 551 */ 552 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 553 const char *syms[], size_t syms_len) { 554 assert(agent_lib != NULL, "sanity check"); 555 const char *lib_name; 556 void *handle = agent_lib->os_lib(); 557 void *entryName = NULL; 558 char *agent_function_name; 559 size_t i; 560 561 // If checking then use the agent name otherwise test is_static_lib() to 562 // see how to process this lookup 563 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 564 for (i = 0; i < syms_len; i++) { 565 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 566 if (agent_function_name == NULL) { 567 break; 568 } 569 entryName = dll_lookup(handle, agent_function_name); 570 FREE_C_HEAP_ARRAY(char, agent_function_name); 571 if (entryName != NULL) { 572 break; 573 } 574 } 575 return entryName; 576 } 577 578 // See if the passed in agent is statically linked into the VM image. 579 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 580 size_t syms_len) { 581 void *ret; 582 void *proc_handle; 583 void *save_handle; 584 585 assert(agent_lib != NULL, "sanity check"); 586 if (agent_lib->name() == NULL) { 587 return false; 588 } 589 proc_handle = get_default_process_handle(); 590 // Check for Agent_OnLoad/Attach_lib_name function 591 save_handle = agent_lib->os_lib(); 592 // We want to look in this process' symbol table. 593 agent_lib->set_os_lib(proc_handle); 594 ret = find_agent_function(agent_lib, true, syms, syms_len); 595 if (ret != NULL) { 596 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 597 agent_lib->set_valid(); 598 agent_lib->set_static_lib(true); 599 return true; 600 } 601 agent_lib->set_os_lib(save_handle); 602 return false; 603 } 604 605 // --------------------- heap allocation utilities --------------------- 606 607 char *os::strdup(const char *str, MEMFLAGS flags) { 608 size_t size = strlen(str); 609 char *dup_str = (char *)malloc(size + 1, flags); 610 if (dup_str == NULL) return NULL; 611 strcpy(dup_str, str); 612 return dup_str; 613 } 614 615 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) { 616 char* p = os::strdup(str, flags); 617 if (p == NULL) { 618 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom"); 619 } 620 return p; 621 } 622 623 624 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 625 626 #ifdef ASSERT 627 628 static void verify_memory(void* ptr) { 629 GuardedMemory guarded(ptr); 630 if (!guarded.verify_guards()) { 631 LogTarget(Warning, malloc, free) lt; 632 ResourceMark rm; 633 LogStream ls(lt); 634 ls.print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 635 ls.print_cr("## memory stomp:"); 636 guarded.print_on(&ls); 637 fatal("memory stomping error"); 638 } 639 } 640 641 #endif 642 643 // 644 // This function supports testing of the malloc out of memory 645 // condition without really running the system out of memory. 646 // 647 static bool has_reached_max_malloc_test_peak(size_t alloc_size) { 648 if (MallocMaxTestWords > 0) { 649 size_t words = (alloc_size / BytesPerWord); 650 651 if ((cur_malloc_words + words) > MallocMaxTestWords) { 652 return true; 653 } 654 Atomic::add(words, &cur_malloc_words); 655 } 656 return false; 657 } 658 659 void* os::malloc(size_t size, MEMFLAGS flags) { 660 return os::malloc(size, flags, CALLER_PC); 661 } 662 663 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 664 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 665 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 666 667 // Since os::malloc can be called when the libjvm.{dll,so} is 668 // first loaded and we don't have a thread yet we must accept NULL also here. 669 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()), 670 "malloc() not allowed when crash protection is set"); 671 672 if (size == 0) { 673 // return a valid pointer if size is zero 674 // if NULL is returned the calling functions assume out of memory. 675 size = 1; 676 } 677 678 // NMT support 679 NMT_TrackingLevel level = MemTracker::tracking_level(); 680 size_t nmt_header_size = MemTracker::malloc_header_size(level); 681 682 #ifndef ASSERT 683 const size_t alloc_size = size + nmt_header_size; 684 #else 685 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size); 686 if (size + nmt_header_size > alloc_size) { // Check for rollover. 687 return NULL; 688 } 689 #endif 690 691 // For the test flag -XX:MallocMaxTestWords 692 if (has_reached_max_malloc_test_peak(size)) { 693 return NULL; 694 } 695 696 u_char* ptr; 697 ptr = (u_char*)::malloc(alloc_size); 698 699 #ifdef ASSERT 700 if (ptr == NULL) { 701 return NULL; 702 } 703 // Wrap memory with guard 704 GuardedMemory guarded(ptr, size + nmt_header_size); 705 ptr = guarded.get_user_ptr(); 706 #endif 707 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 708 log_warning(malloc, free)("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 709 breakpoint(); 710 } 711 debug_only(if (paranoid) verify_memory(ptr)); 712 713 // we do not track guard memory 714 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level); 715 } 716 717 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 718 return os::realloc(memblock, size, flags, CALLER_PC); 719 } 720 721 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 722 723 // For the test flag -XX:MallocMaxTestWords 724 if (has_reached_max_malloc_test_peak(size)) { 725 return NULL; 726 } 727 728 if (size == 0) { 729 // return a valid pointer if size is zero 730 // if NULL is returned the calling functions assume out of memory. 731 size = 1; 732 } 733 734 #ifndef ASSERT 735 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 736 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 737 // NMT support 738 void* membase = MemTracker::record_free(memblock); 739 NMT_TrackingLevel level = MemTracker::tracking_level(); 740 size_t nmt_header_size = MemTracker::malloc_header_size(level); 741 void* ptr = ::realloc(membase, size + nmt_header_size); 742 return MemTracker::record_malloc(ptr, size, memflags, stack, level); 743 #else 744 if (memblock == NULL) { 745 return os::malloc(size, memflags, stack); 746 } 747 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 748 log_warning(malloc, free)("os::realloc caught " PTR_FORMAT, p2i(memblock)); 749 breakpoint(); 750 } 751 // NMT support 752 void* membase = MemTracker::malloc_base(memblock); 753 verify_memory(membase); 754 // always move the block 755 void* ptr = os::malloc(size, memflags, stack); 756 // Copy to new memory if malloc didn't fail 757 if (ptr != NULL ) { 758 GuardedMemory guarded(MemTracker::malloc_base(memblock)); 759 // Guard's user data contains NMT header 760 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock); 761 memcpy(ptr, memblock, MIN2(size, memblock_size)); 762 if (paranoid) verify_memory(MemTracker::malloc_base(ptr)); 763 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 764 log_warning(malloc, free)("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 765 breakpoint(); 766 } 767 os::free(memblock); 768 } 769 return ptr; 770 #endif 771 } 772 773 774 void os::free(void *memblock) { 775 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 776 #ifdef ASSERT 777 if (memblock == NULL) return; 778 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 779 log_warning(malloc, free)("os::free caught " PTR_FORMAT, p2i(memblock)); 780 breakpoint(); 781 } 782 void* membase = MemTracker::record_free(memblock); 783 verify_memory(membase); 784 785 GuardedMemory guarded(membase); 786 size_t size = guarded.get_user_size(); 787 inc_stat_counter(&free_bytes, size); 788 membase = guarded.release_for_freeing(); 789 ::free(membase); 790 #else 791 void* membase = MemTracker::record_free(memblock); 792 ::free(membase); 793 #endif 794 } 795 796 void os::init_random(unsigned int initval) { 797 _rand_seed = initval; 798 } 799 800 801 static int random_helper(unsigned int rand_seed) { 802 /* standard, well-known linear congruential random generator with 803 * next_rand = (16807*seed) mod (2**31-1) 804 * see 805 * (1) "Random Number Generators: Good Ones Are Hard to Find", 806 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 807 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 808 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 809 */ 810 const unsigned int a = 16807; 811 const unsigned int m = 2147483647; 812 const int q = m / a; assert(q == 127773, "weird math"); 813 const int r = m % a; assert(r == 2836, "weird math"); 814 815 // compute az=2^31p+q 816 unsigned int lo = a * (rand_seed & 0xFFFF); 817 unsigned int hi = a * (rand_seed >> 16); 818 lo += (hi & 0x7FFF) << 16; 819 820 // if q overflowed, ignore the overflow and increment q 821 if (lo > m) { 822 lo &= m; 823 ++lo; 824 } 825 lo += hi >> 15; 826 827 // if (p+q) overflowed, ignore the overflow and increment (p+q) 828 if (lo > m) { 829 lo &= m; 830 ++lo; 831 } 832 return lo; 833 } 834 835 int os::random() { 836 // Make updating the random seed thread safe. 837 while (true) { 838 unsigned int seed = _rand_seed; 839 unsigned int rand = random_helper(seed); 840 if (Atomic::cmpxchg(rand, &_rand_seed, seed) == seed) { 841 return static_cast<int>(rand); 842 } 843 } 844 } 845 846 // The INITIALIZED state is distinguished from the SUSPENDED state because the 847 // conditions in which a thread is first started are different from those in which 848 // a suspension is resumed. These differences make it hard for us to apply the 849 // tougher checks when starting threads that we want to do when resuming them. 850 // However, when start_thread is called as a result of Thread.start, on a Java 851 // thread, the operation is synchronized on the Java Thread object. So there 852 // cannot be a race to start the thread and hence for the thread to exit while 853 // we are working on it. Non-Java threads that start Java threads either have 854 // to do so in a context in which races are impossible, or should do appropriate 855 // locking. 856 857 void os::start_thread(Thread* thread) { 858 // guard suspend/resume 859 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 860 OSThread* osthread = thread->osthread(); 861 osthread->set_state(RUNNABLE); 862 pd_start_thread(thread); 863 } 864 865 void os::abort(bool dump_core) { 866 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL); 867 } 868 869 //--------------------------------------------------------------------------- 870 // Helper functions for fatal error handler 871 872 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 873 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 874 875 int cols = 0; 876 int cols_per_line = 0; 877 switch (unitsize) { 878 case 1: cols_per_line = 16; break; 879 case 2: cols_per_line = 8; break; 880 case 4: cols_per_line = 4; break; 881 case 8: cols_per_line = 2; break; 882 default: return; 883 } 884 885 address p = start; 886 st->print(PTR_FORMAT ": ", p2i(start)); 887 while (p < end) { 888 switch (unitsize) { 889 case 1: st->print("%02x", *(u1*)p); break; 890 case 2: st->print("%04x", *(u2*)p); break; 891 case 4: st->print("%08x", *(u4*)p); break; 892 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 893 } 894 p += unitsize; 895 cols++; 896 if (cols >= cols_per_line && p < end) { 897 cols = 0; 898 st->cr(); 899 st->print(PTR_FORMAT ": ", p2i(p)); 900 } else { 901 st->print(" "); 902 } 903 } 904 st->cr(); 905 } 906 907 void os::print_environment_variables(outputStream* st, const char** env_list) { 908 if (env_list) { 909 st->print_cr("Environment Variables:"); 910 911 for (int i = 0; env_list[i] != NULL; i++) { 912 char *envvar = ::getenv(env_list[i]); 913 if (envvar != NULL) { 914 st->print("%s", env_list[i]); 915 st->print("="); 916 st->print_cr("%s", envvar); 917 } 918 } 919 } 920 } 921 922 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) { 923 // cpu 924 st->print("CPU:"); 925 st->print("total %d", os::processor_count()); 926 // It's not safe to query number of active processors after crash 927 // st->print("(active %d)", os::active_processor_count()); but we can 928 // print the initial number of active processors. 929 // We access the raw value here because the assert in the accessor will 930 // fail if the crash occurs before initialization of this value. 931 st->print(" (initial active %d)", _initial_active_processor_count); 932 st->print(" %s", VM_Version::features_string()); 933 st->cr(); 934 pd_print_cpu_info(st, buf, buflen); 935 } 936 937 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version 938 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) { 939 st->print("Host: "); 940 #ifndef PRODUCT 941 if (get_host_name(buf, buflen)) { 942 st->print("%s, ", buf); 943 } 944 #endif // PRODUCT 945 get_summary_cpu_info(buf, buflen); 946 st->print("%s, ", buf); 947 size_t mem = physical_memory()/G; 948 if (mem == 0) { // for low memory systems 949 mem = physical_memory()/M; 950 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem); 951 } else { 952 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem); 953 } 954 get_summary_os_info(buf, buflen); 955 st->print_raw(buf); 956 st->cr(); 957 } 958 959 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) { 960 const int secs_per_day = 86400; 961 const int secs_per_hour = 3600; 962 const int secs_per_min = 60; 963 964 time_t tloc; 965 (void)time(&tloc); 966 char* timestring = ctime(&tloc); // ctime adds newline. 967 // edit out the newline 968 char* nl = strchr(timestring, '\n'); 969 if (nl != NULL) { 970 *nl = '\0'; 971 } 972 973 struct tm tz; 974 if (localtime_pd(&tloc, &tz) != NULL) { 975 ::strftime(buf, buflen, "%Z", &tz); 976 st->print("Time: %s %s", timestring, buf); 977 } else { 978 st->print("Time: %s", timestring); 979 } 980 981 double t = os::elapsedTime(); 982 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 983 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 984 // before printf. We lost some precision, but who cares? 985 int eltime = (int)t; // elapsed time in seconds 986 987 // print elapsed time in a human-readable format: 988 int eldays = eltime / secs_per_day; 989 int day_secs = eldays * secs_per_day; 990 int elhours = (eltime - day_secs) / secs_per_hour; 991 int hour_secs = elhours * secs_per_hour; 992 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 993 int minute_secs = elmins * secs_per_min; 994 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 995 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 996 } 997 998 // moved from debug.cpp (used to be find()) but still called from there 999 // The verbose parameter is only set by the debug code in one case 1000 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 1001 address addr = (address)x; 1002 // Handle NULL first, so later checks don't need to protect against it. 1003 if (addr == NULL) { 1004 st->print_cr("0x0 is NULL"); 1005 return; 1006 } 1007 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 1008 if (b != NULL) { 1009 if (b->is_buffer_blob()) { 1010 // the interpreter is generated into a buffer blob 1011 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 1012 if (i != NULL) { 1013 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin())); 1014 i->print_on(st); 1015 return; 1016 } 1017 if (Interpreter::contains(addr)) { 1018 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 1019 " (not bytecode specific)", p2i(addr)); 1020 return; 1021 } 1022 // 1023 if (AdapterHandlerLibrary::contains(b)) { 1024 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin())); 1025 AdapterHandlerLibrary::print_handler_on(st, b); 1026 } 1027 // the stubroutines are generated into a buffer blob 1028 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 1029 if (d != NULL) { 1030 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin())); 1031 d->print_on(st); 1032 st->cr(); 1033 return; 1034 } 1035 if (StubRoutines::contains(addr)) { 1036 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr)); 1037 return; 1038 } 1039 // the InlineCacheBuffer is using stubs generated into a buffer blob 1040 if (InlineCacheBuffer::contains(addr)) { 1041 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr)); 1042 return; 1043 } 1044 VtableStub* v = VtableStubs::stub_containing(addr); 1045 if (v != NULL) { 1046 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point())); 1047 v->print_on(st); 1048 st->cr(); 1049 return; 1050 } 1051 } 1052 nmethod* nm = b->as_nmethod_or_null(); 1053 if (nm != NULL) { 1054 ResourceMark rm; 1055 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 1056 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm)); 1057 if (verbose) { 1058 st->print(" for "); 1059 nm->method()->print_value_on(st); 1060 } 1061 st->cr(); 1062 nm->print_nmethod(verbose); 1063 return; 1064 } 1065 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin())); 1066 b->print_on(st); 1067 return; 1068 } 1069 1070 if (Universe::heap()->is_in(addr)) { 1071 HeapWord* p = Universe::heap()->block_start(addr); 1072 bool print = false; 1073 // If we couldn't find it it just may mean that heap wasn't parsable 1074 // See if we were just given an oop directly 1075 if (p != NULL && Universe::heap()->block_is_obj(p)) { 1076 print = true; 1077 } else if (p == NULL && oopDesc::is_oop(oop(addr))) { 1078 p = (HeapWord*) addr; 1079 print = true; 1080 } 1081 if (print) { 1082 if (p == (HeapWord*) addr) { 1083 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr)); 1084 } else { 1085 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p)); 1086 } 1087 oop(p)->print_on(st); 1088 return; 1089 } 1090 } else { 1091 if (Universe::heap()->is_in_reserved(addr)) { 1092 st->print_cr(INTPTR_FORMAT " is an unallocated location " 1093 "in the heap", p2i(addr)); 1094 return; 1095 } 1096 } 1097 if (JNIHandles::is_global_handle((jobject) addr)) { 1098 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr)); 1099 return; 1100 } 1101 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 1102 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr)); 1103 return; 1104 } 1105 #ifndef PRODUCT 1106 // we don't keep the block list in product mode 1107 if (JNIHandles::is_local_handle((jobject) addr)) { 1108 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr)); 1109 return; 1110 } 1111 #endif 1112 1113 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) { 1114 // Check for privilege stack 1115 if (thread->privileged_stack_top() != NULL && 1116 thread->privileged_stack_top()->contains(addr)) { 1117 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1118 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread)); 1119 if (verbose) thread->print_on(st); 1120 return; 1121 } 1122 // If the addr is a java thread print information about that. 1123 if (addr == (address)thread) { 1124 if (verbose) { 1125 thread->print_on(st); 1126 } else { 1127 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr)); 1128 } 1129 return; 1130 } 1131 // If the addr is in the stack region for this thread then report that 1132 // and print thread info 1133 if (thread->on_local_stack(addr)) { 1134 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1135 INTPTR_FORMAT, p2i(addr), p2i(thread)); 1136 if (verbose) thread->print_on(st); 1137 return; 1138 } 1139 } 1140 1141 // Check if in metaspace and print types that have vptrs (only method now) 1142 if (Metaspace::contains(addr)) { 1143 if (Method::has_method_vptr((const void*)addr)) { 1144 ((Method*)addr)->print_value_on(st); 1145 st->cr(); 1146 } else { 1147 // Use addr->print() from the debugger instead (not here) 1148 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr)); 1149 } 1150 return; 1151 } 1152 1153 // Try an OS specific find 1154 if (os::find(addr, st)) { 1155 return; 1156 } 1157 1158 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr)); 1159 } 1160 1161 // Looks like all platforms can use the same function to check if C 1162 // stack is walkable beyond current frame. The check for fp() is not 1163 // necessary on Sparc, but it's harmless. 1164 bool os::is_first_C_frame(frame* fr) { 1165 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1166 // Check usp first, because if that's bad the other accessors may fault 1167 // on some architectures. Ditto ufp second, etc. 1168 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1169 // sp on amd can be 32 bit aligned. 1170 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1171 1172 uintptr_t usp = (uintptr_t)fr->sp(); 1173 if ((usp & sp_align_mask) != 0) return true; 1174 1175 uintptr_t ufp = (uintptr_t)fr->fp(); 1176 if ((ufp & fp_align_mask) != 0) return true; 1177 1178 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1179 if ((old_sp & sp_align_mask) != 0) return true; 1180 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1181 1182 uintptr_t old_fp = (uintptr_t)fr->link(); 1183 if ((old_fp & fp_align_mask) != 0) return true; 1184 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1185 1186 // stack grows downwards; if old_fp is below current fp or if the stack 1187 // frame is too large, either the stack is corrupted or fp is not saved 1188 // on stack (i.e. on x86, ebp may be used as general register). The stack 1189 // is not walkable beyond current frame. 1190 if (old_fp < ufp) return true; 1191 if (old_fp - ufp > 64 * K) return true; 1192 1193 return false; 1194 } 1195 1196 1197 // Set up the boot classpath. 1198 1199 char* os::format_boot_path(const char* format_string, 1200 const char* home, 1201 int home_len, 1202 char fileSep, 1203 char pathSep) { 1204 assert((fileSep == '/' && pathSep == ':') || 1205 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1206 1207 // Scan the format string to determine the length of the actual 1208 // boot classpath, and handle platform dependencies as well. 1209 int formatted_path_len = 0; 1210 const char* p; 1211 for (p = format_string; *p != 0; ++p) { 1212 if (*p == '%') formatted_path_len += home_len - 1; 1213 ++formatted_path_len; 1214 } 1215 1216 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1217 if (formatted_path == NULL) { 1218 return NULL; 1219 } 1220 1221 // Create boot classpath from format, substituting separator chars and 1222 // java home directory. 1223 char* q = formatted_path; 1224 for (p = format_string; *p != 0; ++p) { 1225 switch (*p) { 1226 case '%': 1227 strcpy(q, home); 1228 q += home_len; 1229 break; 1230 case '/': 1231 *q++ = fileSep; 1232 break; 1233 case ':': 1234 *q++ = pathSep; 1235 break; 1236 default: 1237 *q++ = *p; 1238 } 1239 } 1240 *q = '\0'; 1241 1242 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1243 return formatted_path; 1244 } 1245 1246 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N') 1247 // that ensures automatic closing of the file on exec. If it can not find support in 1248 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic 1249 // closing of the file on exec. 1250 FILE* os::fopen(const char* path, const char* mode) { 1251 char modified_mode[20]; 1252 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer"); 1253 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode); 1254 FILE* file = ::fopen(path, modified_mode); 1255 1256 #if !(defined LINUX || defined BSD || defined _WINDOWS) 1257 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N' 1258 // is not supported as mode in fopen 1259 if (file != NULL) { 1260 int fd = fileno(file); 1261 if (fd != -1) { 1262 int fd_flags = fcntl(fd, F_GETFD); 1263 if (fd_flags != -1) { 1264 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC); 1265 } 1266 } 1267 } 1268 #endif 1269 1270 return file; 1271 } 1272 1273 bool os::set_boot_path(char fileSep, char pathSep) { 1274 const char* home = Arguments::get_java_home(); 1275 int home_len = (int)strlen(home); 1276 1277 struct stat st; 1278 1279 // modular image if "modules" jimage exists 1280 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep); 1281 if (jimage == NULL) return false; 1282 bool has_jimage = (os::stat(jimage, &st) == 0); 1283 if (has_jimage) { 1284 Arguments::set_sysclasspath(jimage, true); 1285 FREE_C_HEAP_ARRAY(char, jimage); 1286 return true; 1287 } 1288 FREE_C_HEAP_ARRAY(char, jimage); 1289 1290 // check if developer build with exploded modules 1291 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep); 1292 if (base_classes == NULL) return false; 1293 if (os::stat(base_classes, &st) == 0) { 1294 Arguments::set_sysclasspath(base_classes, false); 1295 FREE_C_HEAP_ARRAY(char, base_classes); 1296 return true; 1297 } 1298 FREE_C_HEAP_ARRAY(char, base_classes); 1299 1300 return false; 1301 } 1302 1303 /* 1304 * Splits a path, based on its separator, the number of 1305 * elements is returned back in n. 1306 * It is the callers responsibility to: 1307 * a> check the value of n, and n may be 0. 1308 * b> ignore any empty path elements 1309 * c> free up the data. 1310 */ 1311 char** os::split_path(const char* path, int* n) { 1312 *n = 0; 1313 if (path == NULL || strlen(path) == 0) { 1314 return NULL; 1315 } 1316 const char psepchar = *os::path_separator(); 1317 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1318 if (inpath == NULL) { 1319 return NULL; 1320 } 1321 strcpy(inpath, path); 1322 int count = 1; 1323 char* p = strchr(inpath, psepchar); 1324 // Get a count of elements to allocate memory 1325 while (p != NULL) { 1326 count++; 1327 p++; 1328 p = strchr(p, psepchar); 1329 } 1330 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1331 if (opath == NULL) { 1332 return NULL; 1333 } 1334 1335 // do the actual splitting 1336 p = inpath; 1337 for (int i = 0 ; i < count ; i++) { 1338 size_t len = strcspn(p, os::path_separator()); 1339 if (len > JVM_MAXPATHLEN) { 1340 return NULL; 1341 } 1342 // allocate the string and add terminator storage 1343 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1344 if (s == NULL) { 1345 return NULL; 1346 } 1347 strncpy(s, p, len); 1348 s[len] = '\0'; 1349 opath[i] = s; 1350 p += len + 1; 1351 } 1352 FREE_C_HEAP_ARRAY(char, inpath); 1353 *n = count; 1354 return opath; 1355 } 1356 1357 void os::set_memory_serialize_page(address page) { 1358 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1359 _mem_serialize_page = (volatile int32_t *)page; 1360 // We initialize the serialization page shift count here 1361 // We assume a cache line size of 64 bytes 1362 assert(SerializePageShiftCount == count, "JavaThread size changed; " 1363 "SerializePageShiftCount constant should be %d", count); 1364 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1365 } 1366 1367 static volatile intptr_t SerializePageLock = 0; 1368 1369 // This method is called from signal handler when SIGSEGV occurs while the current 1370 // thread tries to store to the "read-only" memory serialize page during state 1371 // transition. 1372 void os::block_on_serialize_page_trap() { 1373 log_debug(safepoint)("Block until the serialize page permission restored"); 1374 1375 // When VMThread is holding the SerializePageLock during modifying the 1376 // access permission of the memory serialize page, the following call 1377 // will block until the permission of that page is restored to rw. 1378 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1379 // this case, it's OK as the signal is synchronous and we know precisely when 1380 // it can occur. 1381 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1382 Thread::muxRelease(&SerializePageLock); 1383 } 1384 1385 // Serialize all thread state variables 1386 void os::serialize_thread_states() { 1387 // On some platforms such as Solaris & Linux, the time duration of the page 1388 // permission restoration is observed to be much longer than expected due to 1389 // scheduler starvation problem etc. To avoid the long synchronization 1390 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1391 // the mutator thread if such case is encountered. See bug 6546278 for details. 1392 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1393 os::protect_memory((char *)os::get_memory_serialize_page(), 1394 os::vm_page_size(), MEM_PROT_READ); 1395 os::protect_memory((char *)os::get_memory_serialize_page(), 1396 os::vm_page_size(), MEM_PROT_RW); 1397 Thread::muxRelease(&SerializePageLock); 1398 } 1399 1400 // Returns true if the current stack pointer is above the stack shadow 1401 // pages, false otherwise. 1402 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) { 1403 if (!thread->is_Java_thread()) return false; 1404 // Check if we have StackShadowPages above the yellow zone. This parameter 1405 // is dependent on the depth of the maximum VM call stack possible from 1406 // the handler for stack overflow. 'instanceof' in the stack overflow 1407 // handler or a println uses at least 8k stack of VM and native code 1408 // respectively. 1409 const int framesize_in_bytes = 1410 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1411 1412 address limit = ((JavaThread*)thread)->stack_end() + 1413 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size()); 1414 1415 return sp > (limit + framesize_in_bytes); 1416 } 1417 1418 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1419 assert(min_pages > 0, "sanity"); 1420 if (UseLargePages) { 1421 const size_t max_page_size = region_size / min_pages; 1422 1423 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1424 const size_t page_size = _page_sizes[i]; 1425 if (page_size <= max_page_size) { 1426 if (!must_be_aligned || is_aligned(region_size, page_size)) { 1427 return page_size; 1428 } 1429 } 1430 } 1431 } 1432 1433 return vm_page_size(); 1434 } 1435 1436 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1437 return page_size_for_region(region_size, min_pages, true); 1438 } 1439 1440 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1441 return page_size_for_region(region_size, min_pages, false); 1442 } 1443 1444 static const char* errno_to_string (int e, bool short_text) { 1445 #define ALL_SHARED_ENUMS(X) \ 1446 X(E2BIG, "Argument list too long") \ 1447 X(EACCES, "Permission denied") \ 1448 X(EADDRINUSE, "Address in use") \ 1449 X(EADDRNOTAVAIL, "Address not available") \ 1450 X(EAFNOSUPPORT, "Address family not supported") \ 1451 X(EAGAIN, "Resource unavailable, try again") \ 1452 X(EALREADY, "Connection already in progress") \ 1453 X(EBADF, "Bad file descriptor") \ 1454 X(EBADMSG, "Bad message") \ 1455 X(EBUSY, "Device or resource busy") \ 1456 X(ECANCELED, "Operation canceled") \ 1457 X(ECHILD, "No child processes") \ 1458 X(ECONNABORTED, "Connection aborted") \ 1459 X(ECONNREFUSED, "Connection refused") \ 1460 X(ECONNRESET, "Connection reset") \ 1461 X(EDEADLK, "Resource deadlock would occur") \ 1462 X(EDESTADDRREQ, "Destination address required") \ 1463 X(EDOM, "Mathematics argument out of domain of function") \ 1464 X(EEXIST, "File exists") \ 1465 X(EFAULT, "Bad address") \ 1466 X(EFBIG, "File too large") \ 1467 X(EHOSTUNREACH, "Host is unreachable") \ 1468 X(EIDRM, "Identifier removed") \ 1469 X(EILSEQ, "Illegal byte sequence") \ 1470 X(EINPROGRESS, "Operation in progress") \ 1471 X(EINTR, "Interrupted function") \ 1472 X(EINVAL, "Invalid argument") \ 1473 X(EIO, "I/O error") \ 1474 X(EISCONN, "Socket is connected") \ 1475 X(EISDIR, "Is a directory") \ 1476 X(ELOOP, "Too many levels of symbolic links") \ 1477 X(EMFILE, "Too many open files") \ 1478 X(EMLINK, "Too many links") \ 1479 X(EMSGSIZE, "Message too large") \ 1480 X(ENAMETOOLONG, "Filename too long") \ 1481 X(ENETDOWN, "Network is down") \ 1482 X(ENETRESET, "Connection aborted by network") \ 1483 X(ENETUNREACH, "Network unreachable") \ 1484 X(ENFILE, "Too many files open in system") \ 1485 X(ENOBUFS, "No buffer space available") \ 1486 X(ENODATA, "No message is available on the STREAM head read queue") \ 1487 X(ENODEV, "No such device") \ 1488 X(ENOENT, "No such file or directory") \ 1489 X(ENOEXEC, "Executable file format error") \ 1490 X(ENOLCK, "No locks available") \ 1491 X(ENOLINK, "Reserved") \ 1492 X(ENOMEM, "Not enough space") \ 1493 X(ENOMSG, "No message of the desired type") \ 1494 X(ENOPROTOOPT, "Protocol not available") \ 1495 X(ENOSPC, "No space left on device") \ 1496 X(ENOSR, "No STREAM resources") \ 1497 X(ENOSTR, "Not a STREAM") \ 1498 X(ENOSYS, "Function not supported") \ 1499 X(ENOTCONN, "The socket is not connected") \ 1500 X(ENOTDIR, "Not a directory") \ 1501 X(ENOTEMPTY, "Directory not empty") \ 1502 X(ENOTSOCK, "Not a socket") \ 1503 X(ENOTSUP, "Not supported") \ 1504 X(ENOTTY, "Inappropriate I/O control operation") \ 1505 X(ENXIO, "No such device or address") \ 1506 X(EOPNOTSUPP, "Operation not supported on socket") \ 1507 X(EOVERFLOW, "Value too large to be stored in data type") \ 1508 X(EPERM, "Operation not permitted") \ 1509 X(EPIPE, "Broken pipe") \ 1510 X(EPROTO, "Protocol error") \ 1511 X(EPROTONOSUPPORT, "Protocol not supported") \ 1512 X(EPROTOTYPE, "Protocol wrong type for socket") \ 1513 X(ERANGE, "Result too large") \ 1514 X(EROFS, "Read-only file system") \ 1515 X(ESPIPE, "Invalid seek") \ 1516 X(ESRCH, "No such process") \ 1517 X(ETIME, "Stream ioctl() timeout") \ 1518 X(ETIMEDOUT, "Connection timed out") \ 1519 X(ETXTBSY, "Text file busy") \ 1520 X(EWOULDBLOCK, "Operation would block") \ 1521 X(EXDEV, "Cross-device link") 1522 1523 #define DEFINE_ENTRY(e, text) { e, #e, text }, 1524 1525 static const struct { 1526 int v; 1527 const char* short_text; 1528 const char* long_text; 1529 } table [] = { 1530 1531 ALL_SHARED_ENUMS(DEFINE_ENTRY) 1532 1533 // The following enums are not defined on all platforms. 1534 #ifdef ESTALE 1535 DEFINE_ENTRY(ESTALE, "Reserved") 1536 #endif 1537 #ifdef EDQUOT 1538 DEFINE_ENTRY(EDQUOT, "Reserved") 1539 #endif 1540 #ifdef EMULTIHOP 1541 DEFINE_ENTRY(EMULTIHOP, "Reserved") 1542 #endif 1543 1544 // End marker. 1545 { -1, "Unknown errno", "Unknown error" } 1546 1547 }; 1548 1549 #undef DEFINE_ENTRY 1550 #undef ALL_FLAGS 1551 1552 int i = 0; 1553 while (table[i].v != -1 && table[i].v != e) { 1554 i ++; 1555 } 1556 1557 return short_text ? table[i].short_text : table[i].long_text; 1558 1559 } 1560 1561 const char* os::strerror(int e) { 1562 return errno_to_string(e, false); 1563 } 1564 1565 const char* os::errno_name(int e) { 1566 return errno_to_string(e, true); 1567 } 1568 1569 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) { 1570 LogTarget(Info, pagesize) log; 1571 if (log.is_enabled()) { 1572 LogStream out(log); 1573 1574 out.print("%s: ", str); 1575 for (int i = 0; i < count; ++i) { 1576 out.print(" " SIZE_FORMAT, page_sizes[i]); 1577 } 1578 out.cr(); 1579 } 1580 } 1581 1582 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size) 1583 1584 void os::trace_page_sizes(const char* str, 1585 const size_t region_min_size, 1586 const size_t region_max_size, 1587 const size_t page_size, 1588 const char* base, 1589 const size_t size) { 1590 1591 log_info(pagesize)("%s: " 1592 " min=" SIZE_FORMAT "%s" 1593 " max=" SIZE_FORMAT "%s" 1594 " base=" PTR_FORMAT 1595 " page_size=" SIZE_FORMAT "%s" 1596 " size=" SIZE_FORMAT "%s", 1597 str, 1598 trace_page_size_params(region_min_size), 1599 trace_page_size_params(region_max_size), 1600 p2i(base), 1601 trace_page_size_params(page_size), 1602 trace_page_size_params(size)); 1603 } 1604 1605 void os::trace_page_sizes_for_requested_size(const char* str, 1606 const size_t requested_size, 1607 const size_t page_size, 1608 const size_t alignment, 1609 const char* base, 1610 const size_t size) { 1611 1612 log_info(pagesize)("%s:" 1613 " req_size=" SIZE_FORMAT "%s" 1614 " base=" PTR_FORMAT 1615 " page_size=" SIZE_FORMAT "%s" 1616 " alignment=" SIZE_FORMAT "%s" 1617 " size=" SIZE_FORMAT "%s", 1618 str, 1619 trace_page_size_params(requested_size), 1620 p2i(base), 1621 trace_page_size_params(page_size), 1622 trace_page_size_params(alignment), 1623 trace_page_size_params(size)); 1624 } 1625 1626 1627 // This is the working definition of a server class machine: 1628 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1629 // because the graphics memory (?) sometimes masks physical memory. 1630 // If you want to change the definition of a server class machine 1631 // on some OS or platform, e.g., >=4GB on Windows platforms, 1632 // then you'll have to parameterize this method based on that state, 1633 // as was done for logical processors here, or replicate and 1634 // specialize this method for each platform. (Or fix os to have 1635 // some inheritance structure and use subclassing. Sigh.) 1636 // If you want some platform to always or never behave as a server 1637 // class machine, change the setting of AlwaysActAsServerClassMachine 1638 // and NeverActAsServerClassMachine in globals*.hpp. 1639 bool os::is_server_class_machine() { 1640 // First check for the early returns 1641 if (NeverActAsServerClassMachine) { 1642 return false; 1643 } 1644 if (AlwaysActAsServerClassMachine) { 1645 return true; 1646 } 1647 // Then actually look at the machine 1648 bool result = false; 1649 const unsigned int server_processors = 2; 1650 const julong server_memory = 2UL * G; 1651 // We seem not to get our full complement of memory. 1652 // We allow some part (1/8?) of the memory to be "missing", 1653 // based on the sizes of DIMMs, and maybe graphics cards. 1654 const julong missing_memory = 256UL * M; 1655 1656 /* Is this a server class machine? */ 1657 if ((os::active_processor_count() >= (int)server_processors) && 1658 (os::physical_memory() >= (server_memory - missing_memory))) { 1659 const unsigned int logical_processors = 1660 VM_Version::logical_processors_per_package(); 1661 if (logical_processors > 1) { 1662 const unsigned int physical_packages = 1663 os::active_processor_count() / logical_processors; 1664 if (physical_packages >= server_processors) { 1665 result = true; 1666 } 1667 } else { 1668 result = true; 1669 } 1670 } 1671 return result; 1672 } 1673 1674 void os::initialize_initial_active_processor_count() { 1675 assert(_initial_active_processor_count == 0, "Initial active processor count already set."); 1676 _initial_active_processor_count = active_processor_count(); 1677 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count); 1678 } 1679 1680 void os::SuspendedThreadTask::run() { 1681 internal_do_task(); 1682 _done = true; 1683 } 1684 1685 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1686 return os::pd_create_stack_guard_pages(addr, bytes); 1687 } 1688 1689 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, int file_desc) { 1690 char* result = NULL; 1691 1692 if (file_desc != -1) { 1693 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(), 1694 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file. 1695 result = os::map_memory_to_file(addr, bytes, file_desc); 1696 if (result != NULL) { 1697 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1698 } 1699 } else { 1700 result = pd_reserve_memory(bytes, addr, alignment_hint); 1701 if (result != NULL) { 1702 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1703 } 1704 } 1705 1706 return result; 1707 } 1708 1709 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1710 MEMFLAGS flags) { 1711 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1712 if (result != NULL) { 1713 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1714 MemTracker::record_virtual_memory_type((address)result, flags); 1715 } 1716 1717 return result; 1718 } 1719 1720 char* os::attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc) { 1721 char* result = NULL; 1722 if (file_desc != -1) { 1723 result = pd_attempt_reserve_memory_at(bytes, addr, file_desc); 1724 if (result != NULL) { 1725 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1726 } 1727 } else { 1728 result = pd_attempt_reserve_memory_at(bytes, addr); 1729 if (result != NULL) { 1730 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1731 } 1732 } 1733 return result; 1734 } 1735 1736 void os::split_reserved_memory(char *base, size_t size, 1737 size_t split, bool realloc) { 1738 pd_split_reserved_memory(base, size, split, realloc); 1739 } 1740 1741 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1742 bool res = pd_commit_memory(addr, bytes, executable); 1743 if (res) { 1744 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1745 } 1746 return res; 1747 } 1748 1749 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1750 bool executable) { 1751 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1752 if (res) { 1753 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1754 } 1755 return res; 1756 } 1757 1758 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1759 const char* mesg) { 1760 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1761 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1762 } 1763 1764 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1765 bool executable, const char* mesg) { 1766 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1767 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1768 } 1769 1770 bool os::uncommit_memory(char* addr, size_t bytes) { 1771 bool res; 1772 if (MemTracker::tracking_level() > NMT_minimal) { 1773 Tracker tkr(Tracker::uncommit); 1774 res = pd_uncommit_memory(addr, bytes); 1775 if (res) { 1776 tkr.record((address)addr, bytes); 1777 } 1778 } else { 1779 res = pd_uncommit_memory(addr, bytes); 1780 } 1781 return res; 1782 } 1783 1784 bool os::release_memory(char* addr, size_t bytes) { 1785 bool res; 1786 if (MemTracker::tracking_level() > NMT_minimal) { 1787 Tracker tkr(Tracker::release); 1788 res = pd_release_memory(addr, bytes); 1789 if (res) { 1790 tkr.record((address)addr, bytes); 1791 } 1792 } else { 1793 res = pd_release_memory(addr, bytes); 1794 } 1795 return res; 1796 } 1797 1798 void os::pretouch_memory(void* start, void* end, size_t page_size) { 1799 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) { 1800 *p = 0; 1801 } 1802 } 1803 1804 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1805 char *addr, size_t bytes, bool read_only, 1806 bool allow_exec) { 1807 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1808 if (result != NULL) { 1809 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1810 } 1811 return result; 1812 } 1813 1814 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1815 char *addr, size_t bytes, bool read_only, 1816 bool allow_exec) { 1817 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1818 read_only, allow_exec); 1819 } 1820 1821 bool os::unmap_memory(char *addr, size_t bytes) { 1822 bool result; 1823 if (MemTracker::tracking_level() > NMT_minimal) { 1824 Tracker tkr(Tracker::release); 1825 result = pd_unmap_memory(addr, bytes); 1826 if (result) { 1827 tkr.record((address)addr, bytes); 1828 } 1829 } else { 1830 result = pd_unmap_memory(addr, bytes); 1831 } 1832 return result; 1833 } 1834 1835 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1836 pd_free_memory(addr, bytes, alignment_hint); 1837 } 1838 1839 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1840 pd_realign_memory(addr, bytes, alignment_hint); 1841 } 1842 1843 #ifndef _WINDOWS 1844 /* try to switch state from state "from" to state "to" 1845 * returns the state set after the method is complete 1846 */ 1847 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1848 os::SuspendResume::State to) 1849 { 1850 os::SuspendResume::State result = Atomic::cmpxchg(to, &_state, from); 1851 if (result == from) { 1852 // success 1853 return to; 1854 } 1855 return result; 1856 } 1857 #endif