1 /* 2 * Copyright (c) 1997, 2022, 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/javaClasses.hpp" 28 #include "classfile/moduleEntry.hpp" 29 #include "classfile/systemDictionary.hpp" 30 #include "classfile/vmClasses.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/gcVMOperations.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 #include "memory/resourceArea.hpp" 42 #include "memory/universe.hpp" 43 #include "oops/compressedKlass.hpp" 44 #include "oops/compressedOops.inline.hpp" 45 #include "oops/oop.inline.hpp" 46 #include "prims/jvm_misc.hpp" 47 #include "runtime/arguments.hpp" 48 #include "runtime/atomic.hpp" 49 #include "runtime/frame.inline.hpp" 50 #include "runtime/handles.inline.hpp" 51 #include "runtime/interfaceSupport.inline.hpp" 52 #include "runtime/java.hpp" 53 #include "runtime/javaCalls.hpp" 54 #include "runtime/jniHandles.hpp" 55 #include "runtime/mutexLocker.hpp" 56 #include "runtime/os.inline.hpp" 57 #include "runtime/osThread.hpp" 58 #include "runtime/safefetch.hpp" 59 #include "runtime/sharedRuntime.hpp" 60 #include "runtime/thread.inline.hpp" 61 #include "runtime/threadSMR.hpp" 62 #include "runtime/vmOperations.hpp" 63 #include "runtime/vm_version.hpp" 64 #include "services/attachListener.hpp" 65 #include "services/mallocTracker.hpp" 66 #include "services/memTracker.hpp" 67 #include "services/nmtPreInit.hpp" 68 #include "services/nmtCommon.hpp" 69 #include "services/threadService.hpp" 70 #include "utilities/align.hpp" 71 #include "utilities/count_trailing_zeros.hpp" 72 #include "utilities/defaultStream.hpp" 73 #include "utilities/events.hpp" 74 #include "utilities/powerOfTwo.hpp" 75 76 #ifndef _WINDOWS 77 # include <poll.h> 78 #endif 79 80 # include <signal.h> 81 # include <errno.h> 82 83 OSThread* os::_starting_thread = NULL; 84 address os::_polling_page = NULL; 85 volatile unsigned int os::_rand_seed = 1234567; 86 int os::_processor_count = 0; 87 int os::_initial_active_processor_count = 0; 88 os::PageSizes os::_page_sizes; 89 90 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords 91 92 DEBUG_ONLY(bool os::_mutex_init_done = false;) 93 94 int os::snprintf(char* buf, size_t len, const char* fmt, ...) { 95 va_list args; 96 va_start(args, fmt); 97 int result = os::vsnprintf(buf, len, fmt, args); 98 va_end(args); 99 return result; 100 } 101 102 // Fill in buffer with current local time as an ISO-8601 string. 103 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 104 // Returns buffer, or NULL if it failed. 105 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) { 106 const jlong now = javaTimeMillis(); 107 return os::iso8601_time(now, buffer, buffer_length, utc); 108 } 109 110 // Fill in buffer with an ISO-8601 string corresponding to the given javaTimeMillis value 111 // E.g., yyyy-mm-ddThh:mm:ss-zzzz. 112 // Returns buffer, or NULL if it failed. 113 // This would mostly be a call to 114 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 115 // except that on Windows the %z behaves badly, so we do it ourselves. 116 // Also, people wanted milliseconds on there, 117 // and strftime doesn't do milliseconds. 118 char* os::iso8601_time(jlong milliseconds_since_19700101, char* buffer, size_t buffer_length, bool utc) { 119 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 120 121 // Sanity check the arguments 122 if (buffer == NULL) { 123 assert(false, "NULL buffer"); 124 return NULL; 125 } 126 if (buffer_length < os::iso8601_timestamp_size) { 127 assert(false, "buffer_length too small"); 128 return NULL; 129 } 130 const int milliseconds_per_microsecond = 1000; 131 const time_t seconds_since_19700101 = 132 milliseconds_since_19700101 / milliseconds_per_microsecond; 133 const int milliseconds_after_second = 134 milliseconds_since_19700101 % milliseconds_per_microsecond; 135 // Convert the time value to a tm and timezone variable 136 struct tm time_struct; 137 if (utc) { 138 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 139 assert(false, "Failed gmtime_pd"); 140 return NULL; 141 } 142 } else { 143 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 144 assert(false, "Failed localtime_pd"); 145 return NULL; 146 } 147 } 148 149 const time_t seconds_per_minute = 60; 150 const time_t minutes_per_hour = 60; 151 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 152 153 // No offset when dealing with UTC 154 time_t UTC_to_local = 0; 155 if (!utc) { 156 #if defined(_ALLBSD_SOURCE) || defined(_GNU_SOURCE) 157 UTC_to_local = -(time_struct.tm_gmtoff); 158 #elif defined(_WINDOWS) 159 long zone; 160 _get_timezone(&zone); 161 UTC_to_local = static_cast<time_t>(zone); 162 #else 163 UTC_to_local = timezone; 164 #endif 165 166 // tm_gmtoff already includes adjustment for daylight saving 167 #if !defined(_ALLBSD_SOURCE) && !defined(_GNU_SOURCE) 168 // If daylight savings time is in effect, 169 // we are 1 hour East of our time zone 170 if (time_struct.tm_isdst > 0) { 171 UTC_to_local = UTC_to_local - seconds_per_hour; 172 } 173 #endif 174 } 175 176 // Compute the time zone offset. 177 // localtime_pd() sets timezone to the difference (in seconds) 178 // between UTC and and local time. 179 // ISO 8601 says we need the difference between local time and UTC, 180 // we change the sign of the localtime_pd() result. 181 const time_t local_to_UTC = -(UTC_to_local); 182 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 183 char sign_local_to_UTC = '+'; 184 time_t abs_local_to_UTC = local_to_UTC; 185 if (local_to_UTC < 0) { 186 sign_local_to_UTC = '-'; 187 abs_local_to_UTC = -(abs_local_to_UTC); 188 } 189 // Convert time zone offset seconds to hours and minutes. 190 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 191 const time_t zone_min = 192 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 193 194 // Print an ISO 8601 date and time stamp into the buffer 195 const int year = 1900 + time_struct.tm_year; 196 const int month = 1 + time_struct.tm_mon; 197 const int printed = jio_snprintf(buffer, buffer_length, 198 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d", 199 year, 200 month, 201 time_struct.tm_mday, 202 time_struct.tm_hour, 203 time_struct.tm_min, 204 time_struct.tm_sec, 205 milliseconds_after_second, 206 sign_local_to_UTC, 207 zone_hours, 208 zone_min); 209 if (printed == 0) { 210 assert(false, "Failed jio_printf"); 211 return NULL; 212 } 213 return buffer; 214 } 215 216 OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 217 debug_only(Thread::check_for_dangling_thread_pointer(thread);) 218 219 if ((p >= MinPriority && p <= MaxPriority) || 220 (p == CriticalPriority && thread->is_ConcurrentGC_thread())) { 221 int priority = java_to_os_priority[p]; 222 return set_native_priority(thread, priority); 223 } else { 224 assert(false, "Should not happen"); 225 return OS_ERR; 226 } 227 } 228 229 // The mapping from OS priority back to Java priority may be inexact because 230 // Java priorities can map M:1 with native priorities. If you want the definite 231 // Java priority then use JavaThread::java_priority() 232 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 233 int p; 234 int os_prio; 235 OSReturn ret = get_native_priority(thread, &os_prio); 236 if (ret != OS_OK) return ret; 237 238 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 239 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 240 } else { 241 // niceness values are in reverse order 242 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 243 } 244 priority = (ThreadPriority)p; 245 return OS_OK; 246 } 247 248 bool os::dll_build_name(char* buffer, size_t size, const char* fname) { 249 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX); 250 return (n != -1); 251 } 252 253 #if !defined(LINUX) && !defined(_WINDOWS) 254 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) { 255 committed_start = start; 256 committed_size = size; 257 return true; 258 } 259 #endif 260 261 // Helper for dll_locate_lib. 262 // Pass buffer and printbuffer as we already printed the path to buffer 263 // when we called get_current_directory. This way we avoid another buffer 264 // of size MAX_PATH. 265 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen, 266 const char* pname, char lastchar, const char* fname) { 267 268 // Concatenate path and file name, but don't print double path separators. 269 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ? 270 "" : os::file_separator(); 271 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname); 272 // Check whether file exists. 273 if (ret != -1) { 274 struct stat statbuf; 275 return os::stat(buffer, &statbuf) == 0; 276 } 277 return false; 278 } 279 280 // Frees all memory allocated on the heap for the 281 // supplied array of arrays of chars (a), where n 282 // is the number of elements in the array. 283 static void free_array_of_char_arrays(char** a, size_t n) { 284 while (n > 0) { 285 n--; 286 if (a[n] != NULL) { 287 FREE_C_HEAP_ARRAY(char, a[n]); 288 } 289 } 290 FREE_C_HEAP_ARRAY(char*, a); 291 } 292 293 bool os::dll_locate_lib(char *buffer, size_t buflen, 294 const char* pname, const char* fname) { 295 bool retval = false; 296 297 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX); 298 char* fullfname = NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal); 299 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) { 300 const size_t pnamelen = pname ? strlen(pname) : 0; 301 302 if (pnamelen == 0) { 303 // If no path given, use current working directory. 304 const char* p = get_current_directory(buffer, buflen); 305 if (p != NULL) { 306 const size_t plen = strlen(buffer); 307 const char lastchar = buffer[plen - 1]; 308 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen, 309 "", lastchar, fullfname); 310 } 311 } else if (strchr(pname, *os::path_separator()) != NULL) { 312 // A list of paths. Search for the path that contains the library. 313 size_t n; 314 char** pelements = split_path(pname, &n, fullfnamelen); 315 if (pelements != NULL) { 316 for (size_t i = 0; i < n; i++) { 317 char* path = pelements[i]; 318 // Really shouldn't be NULL, but check can't hurt. 319 size_t plen = (path == NULL) ? 0 : strlen(path); 320 if (plen == 0) { 321 continue; // Skip the empty path values. 322 } 323 const char lastchar = path[plen - 1]; 324 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname); 325 if (retval) break; 326 } 327 // Release the storage allocated by split_path. 328 free_array_of_char_arrays(pelements, n); 329 } 330 } else { 331 // A definite path. 332 const char lastchar = pname[pnamelen-1]; 333 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname); 334 } 335 } 336 337 FREE_C_HEAP_ARRAY(char*, fullfname); 338 return retval; 339 } 340 341 // --------------------- sun.misc.Signal (optional) --------------------- 342 343 344 // SIGBREAK is sent by the keyboard to query the VM state 345 #ifndef SIGBREAK 346 #define SIGBREAK SIGQUIT 347 #endif 348 349 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 350 351 352 static void signal_thread_entry(JavaThread* thread, TRAPS) { 353 os::set_priority(thread, NearMaxPriority); 354 while (true) { 355 int sig; 356 { 357 // FIXME : Currently we have not decided what should be the status 358 // for this java thread blocked here. Once we decide about 359 // that we should fix this. 360 sig = os::signal_wait(); 361 } 362 if (sig == os::sigexitnum_pd()) { 363 // Terminate the signal thread 364 return; 365 } 366 367 switch (sig) { 368 case SIGBREAK: { 369 #if INCLUDE_SERVICES 370 // Check if the signal is a trigger to start the Attach Listener - in that 371 // case don't print stack traces. 372 if (!DisableAttachMechanism) { 373 // Attempt to transit state to AL_INITIALIZING. 374 AttachListenerState cur_state = AttachListener::transit_state(AL_INITIALIZING, AL_NOT_INITIALIZED); 375 if (cur_state == AL_INITIALIZING) { 376 // Attach Listener has been started to initialize. Ignore this signal. 377 continue; 378 } else if (cur_state == AL_NOT_INITIALIZED) { 379 // Start to initialize. 380 if (AttachListener::is_init_trigger()) { 381 // Attach Listener has been initialized. 382 // Accept subsequent request. 383 continue; 384 } else { 385 // Attach Listener could not be started. 386 // So we need to transit the state to AL_NOT_INITIALIZED. 387 AttachListener::set_state(AL_NOT_INITIALIZED); 388 } 389 } else if (AttachListener::check_socket_file()) { 390 // Attach Listener has been started, but unix domain socket file 391 // does not exist. So restart Attach Listener. 392 continue; 393 } 394 } 395 #endif 396 // Print stack traces 397 // Any SIGBREAK operations added here should make sure to flush 398 // the output stream (e.g. tty->flush()) after output. See 4803766. 399 // Each module also prints an extra carriage return after its output. 400 VM_PrintThreads op(tty, PrintConcurrentLocks, false /* no extended info */, true /* print JNI handle info */); 401 VMThread::execute(&op); 402 VM_FindDeadlocks op1(tty); 403 VMThread::execute(&op1); 404 Universe::print_heap_at_SIGBREAK(); 405 if (PrintClassHistogram) { 406 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */); 407 VMThread::execute(&op1); 408 } 409 if (JvmtiExport::should_post_data_dump()) { 410 JvmtiExport::post_data_dump(); 411 } 412 break; 413 } 414 default: { 415 // Dispatch the signal to java 416 HandleMark hm(THREAD); 417 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD); 418 if (klass != NULL) { 419 JavaValue result(T_VOID); 420 JavaCallArguments args; 421 args.push_int(sig); 422 JavaCalls::call_static( 423 &result, 424 klass, 425 vmSymbols::dispatch_name(), 426 vmSymbols::int_void_signature(), 427 &args, 428 THREAD 429 ); 430 } 431 if (HAS_PENDING_EXCEPTION) { 432 // tty is initialized early so we don't expect it to be null, but 433 // if it is we can't risk doing an initialization that might 434 // trigger additional out-of-memory conditions 435 if (tty != NULL) { 436 char klass_name[256]; 437 char tmp_sig_name[16]; 438 const char* sig_name = "UNKNOWN"; 439 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 440 name()->as_klass_external_name(klass_name, 256); 441 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 442 sig_name = tmp_sig_name; 443 warning("Exception %s occurred dispatching signal %s to handler" 444 "- the VM may need to be forcibly terminated", 445 klass_name, sig_name ); 446 } 447 CLEAR_PENDING_EXCEPTION; 448 } 449 } 450 } 451 } 452 } 453 454 void os::init_before_ergo() { 455 initialize_initial_active_processor_count(); 456 // We need to initialize large page support here because ergonomics takes some 457 // decisions depending on large page support and the calculated large page size. 458 large_page_init(); 459 460 StackOverflow::initialize_stack_zone_sizes(); 461 462 // VM version initialization identifies some characteristics of the 463 // platform that are used during ergonomic decisions. 464 VM_Version::init_before_ergo(); 465 } 466 467 void os::initialize_jdk_signal_support(TRAPS) { 468 if (!ReduceSignalUsage) { 469 // Setup JavaThread for processing signals 470 const char* name = "Signal Dispatcher"; 471 Handle thread_oop = JavaThread::create_system_thread_object(name, true /* visible */, CHECK); 472 473 JavaThread* thread = new JavaThread(&signal_thread_entry); 474 JavaThread::vm_exit_on_osthread_failure(thread); 475 476 JavaThread::start_internal_daemon(THREAD, thread, thread_oop, NearMaxPriority); 477 478 // Handle ^BREAK 479 os::signal(SIGBREAK, os::user_handler()); 480 } 481 } 482 483 484 void os::terminate_signal_thread() { 485 if (!ReduceSignalUsage) 486 signal_notify(sigexitnum_pd()); 487 } 488 489 490 // --------------------- loading libraries --------------------- 491 492 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 493 extern struct JavaVM_ main_vm; 494 495 static void* _native_java_library = NULL; 496 497 void* os::native_java_library() { 498 if (_native_java_library == NULL) { 499 char buffer[JVM_MAXPATHLEN]; 500 char ebuf[1024]; 501 502 // Load java dll 503 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(), 504 "java")) { 505 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 506 } 507 if (_native_java_library == NULL) { 508 vm_exit_during_initialization("Unable to load native library", ebuf); 509 } 510 511 #if defined(__OpenBSD__) 512 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 513 // ignore errors 514 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(), 515 "net")) { 516 dll_load(buffer, ebuf, sizeof(ebuf)); 517 } 518 #endif 519 } 520 return _native_java_library; 521 } 522 523 /* 524 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 525 * If check_lib == true then we are looking for an 526 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 527 * this library is statically linked into the image. 528 * If check_lib == false then we will look for the appropriate symbol in the 529 * executable if agent_lib->is_static_lib() == true or in the shared library 530 * referenced by 'handle'. 531 */ 532 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 533 const char *syms[], size_t syms_len) { 534 assert(agent_lib != NULL, "sanity check"); 535 const char *lib_name; 536 void *handle = agent_lib->os_lib(); 537 void *entryName = NULL; 538 char *agent_function_name; 539 size_t i; 540 541 // If checking then use the agent name otherwise test is_static_lib() to 542 // see how to process this lookup 543 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 544 for (i = 0; i < syms_len; i++) { 545 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 546 if (agent_function_name == NULL) { 547 break; 548 } 549 entryName = dll_lookup(handle, agent_function_name); 550 FREE_C_HEAP_ARRAY(char, agent_function_name); 551 if (entryName != NULL) { 552 break; 553 } 554 } 555 return entryName; 556 } 557 558 // See if the passed in agent is statically linked into the VM image. 559 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 560 size_t syms_len) { 561 void *ret; 562 void *proc_handle; 563 void *save_handle; 564 565 assert(agent_lib != NULL, "sanity check"); 566 if (agent_lib->name() == NULL) { 567 return false; 568 } 569 proc_handle = get_default_process_handle(); 570 // Check for Agent_OnLoad/Attach_lib_name function 571 save_handle = agent_lib->os_lib(); 572 // We want to look in this process' symbol table. 573 agent_lib->set_os_lib(proc_handle); 574 ret = find_agent_function(agent_lib, true, syms, syms_len); 575 if (ret != NULL) { 576 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 577 agent_lib->set_valid(); 578 agent_lib->set_static_lib(true); 579 return true; 580 } 581 agent_lib->set_os_lib(save_handle); 582 return false; 583 } 584 585 // --------------------- heap allocation utilities --------------------- 586 587 char *os::strdup(const char *str, MEMFLAGS flags) { 588 size_t size = strlen(str); 589 char *dup_str = (char *)malloc(size + 1, flags); 590 if (dup_str == NULL) return NULL; 591 strcpy(dup_str, str); 592 return dup_str; 593 } 594 595 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) { 596 char* p = os::strdup(str, flags); 597 if (p == NULL) { 598 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom"); 599 } 600 return p; 601 } 602 603 // 604 // This function supports testing of the malloc out of memory 605 // condition without really running the system out of memory. 606 // 607 608 static bool has_reached_max_malloc_test_peak(size_t alloc_size) { 609 if (MallocMaxTestWords > 0) { 610 size_t words = (alloc_size / BytesPerWord); 611 612 if ((cur_malloc_words + words) > MallocMaxTestWords) { 613 return true; 614 } 615 Atomic::add(&cur_malloc_words, words); 616 } 617 return false; 618 } 619 620 #ifdef ASSERT 621 static void check_crash_protection() { 622 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()), 623 "not allowed when crash protection is set"); 624 } 625 static void break_if_ptr_caught(void* ptr) { 626 if (p2i(ptr) == (intptr_t)MallocCatchPtr) { 627 log_warning(malloc, free)("ptr caught: " PTR_FORMAT, p2i(ptr)); 628 breakpoint(); 629 } 630 } 631 #endif // ASSERT 632 633 void* os::malloc(size_t size, MEMFLAGS flags) { 634 return os::malloc(size, flags, CALLER_PC); 635 } 636 637 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 638 639 // Special handling for NMT preinit phase before arguments are parsed 640 void* rc = NULL; 641 if (NMTPreInit::handle_malloc(&rc, size)) { 642 // No need to fill with 0 because DumpSharedSpaces doesn't use these 643 // early allocations. 644 return rc; 645 } 646 647 DEBUG_ONLY(check_crash_protection()); 648 649 // On malloc(0), implementations of malloc(3) have the choice to return either 650 // NULL or a unique non-NULL pointer. To unify libc behavior across our platforms 651 // we chose the latter. 652 size = MAX2((size_t)1, size); 653 654 // For the test flag -XX:MallocMaxTestWords 655 if (has_reached_max_malloc_test_peak(size)) { 656 return NULL; 657 } 658 659 const size_t outer_size = size + MemTracker::overhead_per_malloc(); 660 661 void* const outer_ptr = ::malloc(outer_size); 662 if (outer_ptr == NULL) { 663 return NULL; 664 } 665 666 void* const inner_ptr = MemTracker::record_malloc((address)outer_ptr, size, memflags, stack); 667 668 if (DumpSharedSpaces) { 669 // Need to deterministically fill all the alignment gaps in C++ structures. 670 ::memset(inner_ptr, 0, size); 671 } else { 672 DEBUG_ONLY(::memset(inner_ptr, uninitBlockPad, size);) 673 } 674 DEBUG_ONLY(break_if_ptr_caught(inner_ptr);) 675 return inner_ptr; 676 } 677 678 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 679 return os::realloc(memblock, size, flags, CALLER_PC); 680 } 681 682 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 683 684 // Special handling for NMT preinit phase before arguments are parsed 685 void* rc = NULL; 686 if (NMTPreInit::handle_realloc(&rc, memblock, size)) { 687 return rc; 688 } 689 690 if (memblock == NULL) { 691 return os::malloc(size, memflags, stack); 692 } 693 694 DEBUG_ONLY(check_crash_protection()); 695 696 // On realloc(p, 0), implementers of realloc(3) have the choice to return either 697 // NULL or a unique non-NULL pointer. To unify libc behavior across our platforms 698 // we chose the latter. 699 size = MAX2((size_t)1, size); 700 701 // For the test flag -XX:MallocMaxTestWords 702 if (has_reached_max_malloc_test_peak(size)) { 703 return NULL; 704 } 705 706 const size_t new_outer_size = size + MemTracker::overhead_per_malloc(); 707 708 // If NMT is enabled, this checks for heap overwrites, then de-accounts the old block. 709 void* const old_outer_ptr = MemTracker::record_free(memblock); 710 711 void* const new_outer_ptr = ::realloc(old_outer_ptr, new_outer_size); 712 if (new_outer_ptr == NULL) { 713 return NULL; 714 } 715 716 void* const new_inner_ptr = MemTracker::record_malloc(new_outer_ptr, size, memflags, stack); 717 718 DEBUG_ONLY(break_if_ptr_caught(new_inner_ptr);) 719 720 return new_inner_ptr; 721 } 722 723 void os::free(void *memblock) { 724 725 // Special handling for NMT preinit phase before arguments are parsed 726 if (NMTPreInit::handle_free(memblock)) { 727 return; 728 } 729 730 if (memblock == NULL) { 731 return; 732 } 733 734 DEBUG_ONLY(break_if_ptr_caught(memblock);) 735 736 // If NMT is enabled, this checks for heap overwrites, then de-accounts the old block. 737 void* const old_outer_ptr = MemTracker::record_free(memblock); 738 739 ::free(old_outer_ptr); 740 } 741 742 void os::init_random(unsigned int initval) { 743 _rand_seed = initval; 744 } 745 746 747 int os::next_random(unsigned int rand_seed) { 748 /* standard, well-known linear congruential random generator with 749 * next_rand = (16807*seed) mod (2**31-1) 750 * see 751 * (1) "Random Number Generators: Good Ones Are Hard to Find", 752 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 753 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 754 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 755 */ 756 const unsigned int a = 16807; 757 const unsigned int m = 2147483647; 758 const int q = m / a; assert(q == 127773, "weird math"); 759 const int r = m % a; assert(r == 2836, "weird math"); 760 761 // compute az=2^31p+q 762 unsigned int lo = a * (rand_seed & 0xFFFF); 763 unsigned int hi = a * (rand_seed >> 16); 764 lo += (hi & 0x7FFF) << 16; 765 766 // if q overflowed, ignore the overflow and increment q 767 if (lo > m) { 768 lo &= m; 769 ++lo; 770 } 771 lo += hi >> 15; 772 773 // if (p+q) overflowed, ignore the overflow and increment (p+q) 774 if (lo > m) { 775 lo &= m; 776 ++lo; 777 } 778 return lo; 779 } 780 781 int os::random() { 782 // Make updating the random seed thread safe. 783 while (true) { 784 unsigned int seed = _rand_seed; 785 unsigned int rand = next_random(seed); 786 if (Atomic::cmpxchg(&_rand_seed, seed, rand, memory_order_relaxed) == seed) { 787 return static_cast<int>(rand); 788 } 789 } 790 } 791 792 // The INITIALIZED state is distinguished from the SUSPENDED state because the 793 // conditions in which a thread is first started are different from those in which 794 // a suspension is resumed. These differences make it hard for us to apply the 795 // tougher checks when starting threads that we want to do when resuming them. 796 // However, when start_thread is called as a result of Thread.start, on a Java 797 // thread, the operation is synchronized on the Java Thread object. So there 798 // cannot be a race to start the thread and hence for the thread to exit while 799 // we are working on it. Non-Java threads that start Java threads either have 800 // to do so in a context in which races are impossible, or should do appropriate 801 // locking. 802 803 void os::start_thread(Thread* thread) { 804 OSThread* osthread = thread->osthread(); 805 osthread->set_state(RUNNABLE); 806 pd_start_thread(thread); 807 } 808 809 void os::abort(bool dump_core) { 810 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL); 811 } 812 813 //--------------------------------------------------------------------------- 814 // Helper functions for fatal error handler 815 816 bool os::print_function_and_library_name(outputStream* st, 817 address addr, 818 char* buf, int buflen, 819 bool shorten_paths, 820 bool demangle, 821 bool strip_arguments) { 822 // If no scratch buffer given, allocate one here on stack. 823 // (used during error handling; its a coin toss, really, if on-stack allocation 824 // is worse than (raw) C-heap allocation in that case). 825 char* p = buf; 826 if (p == NULL) { 827 p = (char*)::alloca(O_BUFLEN); 828 buflen = O_BUFLEN; 829 } 830 int offset = 0; 831 bool have_function_name = dll_address_to_function_name(addr, p, buflen, 832 &offset, demangle); 833 bool is_function_descriptor = false; 834 #ifdef HAVE_FUNCTION_DESCRIPTORS 835 // When we deal with a function descriptor instead of a real code pointer, try to 836 // resolve it. There is a small chance that a random pointer given to this function 837 // may just happen to look like a valid descriptor, but this is rare and worth the 838 // risk to see resolved function names. But we will print a little suffix to mark 839 // this as a function descriptor for the reader (see below). 840 if (!have_function_name && os::is_readable_pointer(addr)) { 841 address addr2 = (address)os::resolve_function_descriptor(addr); 842 if (have_function_name = is_function_descriptor = 843 dll_address_to_function_name(addr2, p, buflen, &offset, demangle)) { 844 addr = addr2; 845 } 846 } 847 #endif // HAVE_FUNCTION_DESCRIPTORS 848 849 if (have_function_name) { 850 // Print function name, optionally demangled 851 if (demangle && strip_arguments) { 852 char* args_start = strchr(p, '('); 853 if (args_start != NULL) { 854 *args_start = '\0'; 855 } 856 } 857 // Print offset. Omit printing if offset is zero, which makes the output 858 // more readable if we print function pointers. 859 if (offset == 0) { 860 st->print("%s", p); 861 } else { 862 st->print("%s+%d", p, offset); 863 } 864 } else { 865 st->print(PTR_FORMAT, p2i(addr)); 866 } 867 offset = 0; 868 869 const bool have_library_name = dll_address_to_library_name(addr, p, buflen, &offset); 870 if (have_library_name) { 871 // Cut path parts 872 if (shorten_paths) { 873 char* p2 = strrchr(p, os::file_separator()[0]); 874 if (p2 != NULL) { 875 p = p2 + 1; 876 } 877 } 878 st->print(" in %s", p); 879 if (!have_function_name) { // Omit offset if we already printed the function offset 880 st->print("+%d", offset); 881 } 882 } 883 884 // Write a trailing marker if this was a function descriptor 885 if (have_function_name && is_function_descriptor) { 886 st->print_raw(" (FD)"); 887 } 888 889 return have_function_name || have_library_name; 890 } 891 892 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize, 893 int bytes_per_line, address logical_start) { 894 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 895 896 start = align_down(start, unitsize); 897 logical_start = align_down(logical_start, unitsize); 898 bytes_per_line = align_up(bytes_per_line, 8); 899 900 int cols = 0; 901 int cols_per_line = bytes_per_line / unitsize; 902 903 address p = start; 904 address logical_p = logical_start; 905 906 // Print out the addresses as if we were starting from logical_start. 907 st->print(PTR_FORMAT ": ", p2i(logical_p)); 908 while (p < end) { 909 if (is_readable_pointer(p)) { 910 switch (unitsize) { 911 case 1: st->print("%02x", *(u1*)p); break; 912 case 2: st->print("%04x", *(u2*)p); break; 913 case 4: st->print("%08x", *(u4*)p); break; 914 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 915 } 916 } else { 917 st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????"); 918 } 919 p += unitsize; 920 logical_p += unitsize; 921 cols++; 922 if (cols >= cols_per_line && p < end) { 923 cols = 0; 924 st->cr(); 925 st->print(PTR_FORMAT ": ", p2i(logical_p)); 926 } else { 927 st->print(" "); 928 } 929 } 930 st->cr(); 931 } 932 933 void os::print_dhm(outputStream* st, const char* startStr, long sec) { 934 long days = sec/86400; 935 long hours = (sec/3600) - (days * 24); 936 long minutes = (sec/60) - (days * 1440) - (hours * 60); 937 if (startStr == NULL) startStr = ""; 938 st->print_cr("%s %ld days %ld:%02ld hours", startStr, days, hours, minutes); 939 } 940 941 void os::print_instructions(outputStream* st, address pc, int unitsize) { 942 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc)); 943 print_hex_dump(st, pc - 256, pc + 256, unitsize); 944 } 945 946 void os::print_environment_variables(outputStream* st, const char** env_list) { 947 if (env_list) { 948 st->print_cr("Environment Variables:"); 949 950 for (int i = 0; env_list[i] != NULL; i++) { 951 char *envvar = ::getenv(env_list[i]); 952 if (envvar != NULL) { 953 st->print("%s", env_list[i]); 954 st->print("="); 955 st->print("%s", envvar); 956 // Use separate cr() printing to avoid unnecessary buffer operations that might cause truncation. 957 st->cr(); 958 } 959 } 960 } 961 } 962 963 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) { 964 // cpu 965 st->print("CPU:"); 966 #if defined(__APPLE__) && !defined(ZERO) 967 if (VM_Version::is_cpu_emulated()) { 968 st->print(" (EMULATED)"); 969 } 970 #endif 971 st->print(" total %d", os::processor_count()); 972 // It's not safe to query number of active processors after crash 973 // st->print("(active %d)", os::active_processor_count()); but we can 974 // print the initial number of active processors. 975 // We access the raw value here because the assert in the accessor will 976 // fail if the crash occurs before initialization of this value. 977 st->print(" (initial active %d)", _initial_active_processor_count); 978 st->print(" %s", VM_Version::features_string()); 979 st->cr(); 980 pd_print_cpu_info(st, buf, buflen); 981 } 982 983 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version 984 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) { 985 st->print("Host: "); 986 #ifndef PRODUCT 987 if (get_host_name(buf, buflen)) { 988 st->print("%s, ", buf); 989 } 990 #endif // PRODUCT 991 get_summary_cpu_info(buf, buflen); 992 st->print("%s, ", buf); 993 size_t mem = physical_memory()/G; 994 if (mem == 0) { // for low memory systems 995 mem = physical_memory()/M; 996 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem); 997 } else { 998 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem); 999 } 1000 get_summary_os_info(buf, buflen); 1001 st->print_raw(buf); 1002 st->cr(); 1003 } 1004 1005 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) { 1006 const int secs_per_day = 86400; 1007 const int secs_per_hour = 3600; 1008 const int secs_per_min = 60; 1009 1010 time_t tloc; 1011 (void)time(&tloc); 1012 char* timestring = ctime(&tloc); // ctime adds newline. 1013 // edit out the newline 1014 char* nl = strchr(timestring, '\n'); 1015 if (nl != NULL) { 1016 *nl = '\0'; 1017 } 1018 1019 struct tm tz; 1020 if (localtime_pd(&tloc, &tz) != NULL) { 1021 wchar_t w_buf[80]; 1022 size_t n = ::wcsftime(w_buf, 80, L"%Z", &tz); 1023 if (n > 0) { 1024 ::wcstombs(buf, w_buf, buflen); 1025 st->print("Time: %s %s", timestring, buf); 1026 } else { 1027 st->print("Time: %s", timestring); 1028 } 1029 } else { 1030 st->print("Time: %s", timestring); 1031 } 1032 1033 double t = os::elapsedTime(); 1034 // NOTE: a crash using printf("%f",...) on Linux was historically noted here. 1035 int eltime = (int)t; // elapsed time in seconds 1036 int eltimeFraction = (int) ((t - eltime) * 1000000); 1037 1038 // print elapsed time in a human-readable format: 1039 int eldays = eltime / secs_per_day; 1040 int day_secs = eldays * secs_per_day; 1041 int elhours = (eltime - day_secs) / secs_per_hour; 1042 int hour_secs = elhours * secs_per_hour; 1043 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 1044 int minute_secs = elmins * secs_per_min; 1045 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 1046 st->print_cr(" elapsed time: %d.%06d seconds (%dd %dh %dm %ds)", eltime, eltimeFraction, eldays, elhours, elmins, elsecs); 1047 } 1048 1049 1050 // Check if pointer can be read from (4-byte read access). 1051 // Helps to prove validity of a not-NULL pointer. 1052 // Returns true in very early stages of VM life when stub is not yet generated. 1053 bool os::is_readable_pointer(const void* p) { 1054 int* const aligned = (int*) align_down((intptr_t)p, 4); 1055 int cafebabe = 0xcafebabe; // tester value 1 1056 int deadbeef = 0xdeadbeef; // tester value 2 1057 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef); 1058 } 1059 1060 bool os::is_readable_range(const void* from, const void* to) { 1061 if ((uintptr_t)from >= (uintptr_t)to) return false; 1062 for (uintptr_t p = align_down((uintptr_t)from, min_page_size()); p < (uintptr_t)to; p += min_page_size()) { 1063 if (!is_readable_pointer((const void*)p)) { 1064 return false; 1065 } 1066 } 1067 return true; 1068 } 1069 1070 1071 // moved from debug.cpp (used to be find()) but still called from there 1072 // The verbose parameter is only set by the debug code in one case 1073 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 1074 address addr = (address)x; 1075 // Handle NULL first, so later checks don't need to protect against it. 1076 if (addr == NULL) { 1077 st->print_cr("0x0 is NULL"); 1078 return; 1079 } 1080 1081 // Check if addr points into a code blob. 1082 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 1083 if (b != NULL) { 1084 b->dump_for_addr(addr, st, verbose); 1085 return; 1086 } 1087 1088 // Check if addr points into Java heap. 1089 if (Universe::heap()->print_location(st, addr)) { 1090 return; 1091 } 1092 1093 bool accessible = is_readable_pointer(addr); 1094 1095 // Check if addr is a JNI handle. 1096 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) { 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 } 1106 1107 // Check if addr belongs to a Java thread. 1108 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) { 1109 // If the addr is a java thread print information about that. 1110 if (addr == (address)thread) { 1111 if (verbose) { 1112 thread->print_on(st); 1113 } else { 1114 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr)); 1115 } 1116 return; 1117 } 1118 // If the addr is in the stack region for this thread then report that 1119 // and print thread info 1120 if (thread->is_in_full_stack(addr)) { 1121 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1122 INTPTR_FORMAT, p2i(addr), p2i(thread)); 1123 if (verbose) thread->print_on(st); 1124 return; 1125 } 1126 } 1127 1128 // Check if in metaspace and print types that have vptrs 1129 if (Metaspace::contains(addr)) { 1130 if (Klass::is_valid((Klass*)addr)) { 1131 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr)); 1132 ((Klass*)addr)->print_on(st); 1133 } else if (Method::is_valid_method((const Method*)addr)) { 1134 ((Method*)addr)->print_value_on(st); 1135 st->cr(); 1136 } else { 1137 // Use addr->print() from the debugger instead (not here) 1138 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr)); 1139 } 1140 return; 1141 } 1142 1143 // Compressed klass needs to be decoded first. 1144 #ifdef _LP64 1145 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) { 1146 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr; 1147 Klass* k = CompressedKlassPointers::decode_raw(narrow_klass); 1148 1149 if (Klass::is_valid(k)) { 1150 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k)); 1151 k->print_on(st); 1152 return; 1153 } 1154 } 1155 #endif 1156 1157 // Try an OS specific find 1158 if (os::find(addr, st)) { 1159 return; 1160 } 1161 1162 if (accessible) { 1163 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr)); 1164 if (is_aligned(addr, sizeof(intptr_t))) { 1165 st->print(" " PTR_FORMAT " |", *(intptr_t*)addr); 1166 } 1167 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) { 1168 st->print(" %02x", *(u1*)p); 1169 } 1170 st->cr(); 1171 return; 1172 } 1173 1174 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr)); 1175 } 1176 1177 bool is_pointer_bad(intptr_t* ptr) { 1178 return !is_aligned(ptr, sizeof(uintptr_t)) || !os::is_readable_pointer(ptr); 1179 } 1180 1181 // Looks like all platforms can use the same function to check if C 1182 // stack is walkable beyond current frame. 1183 // Returns true if this is not the case, i.e. the frame is possibly 1184 // the first C frame on the stack. 1185 bool os::is_first_C_frame(frame* fr) { 1186 1187 #ifdef _WINDOWS 1188 return true; // native stack isn't walkable on windows this way. 1189 #endif 1190 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1191 // Check usp first, because if that's bad the other accessors may fault 1192 // on some architectures. Ditto ufp second, etc. 1193 1194 if (is_pointer_bad(fr->sp())) return true; 1195 1196 uintptr_t ufp = (uintptr_t)fr->fp(); 1197 if (is_pointer_bad(fr->fp())) return true; 1198 1199 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1200 if ((uintptr_t)fr->sender_sp() == (uintptr_t)-1 || is_pointer_bad(fr->sender_sp())) return true; 1201 1202 uintptr_t old_fp = (uintptr_t)fr->link_or_null(); 1203 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp || 1204 is_pointer_bad(fr->link_or_null())) return true; 1205 1206 // stack grows downwards; if old_fp is below current fp or if the stack 1207 // frame is too large, either the stack is corrupted or fp is not saved 1208 // on stack (i.e. on x86, ebp may be used as general register). The stack 1209 // is not walkable beyond current frame. 1210 if (old_fp < ufp) return true; 1211 if (old_fp - ufp > 64 * K) return true; 1212 1213 return false; 1214 } 1215 1216 // Set up the boot classpath. 1217 1218 char* os::format_boot_path(const char* format_string, 1219 const char* home, 1220 int home_len, 1221 char fileSep, 1222 char pathSep) { 1223 assert((fileSep == '/' && pathSep == ':') || 1224 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1225 1226 // Scan the format string to determine the length of the actual 1227 // boot classpath, and handle platform dependencies as well. 1228 int formatted_path_len = 0; 1229 const char* p; 1230 for (p = format_string; *p != 0; ++p) { 1231 if (*p == '%') formatted_path_len += home_len - 1; 1232 ++formatted_path_len; 1233 } 1234 1235 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1236 1237 // Create boot classpath from format, substituting separator chars and 1238 // java home directory. 1239 char* q = formatted_path; 1240 for (p = format_string; *p != 0; ++p) { 1241 switch (*p) { 1242 case '%': 1243 strcpy(q, home); 1244 q += home_len; 1245 break; 1246 case '/': 1247 *q++ = fileSep; 1248 break; 1249 case ':': 1250 *q++ = pathSep; 1251 break; 1252 default: 1253 *q++ = *p; 1254 } 1255 } 1256 *q = '\0'; 1257 1258 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1259 return formatted_path; 1260 } 1261 1262 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N') 1263 // that ensures automatic closing of the file on exec. If it can not find support in 1264 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic 1265 // closing of the file on exec. 1266 FILE* os::fopen(const char* path, const char* mode) { 1267 char modified_mode[20]; 1268 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer"); 1269 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode); 1270 FILE* file = ::fopen(path, modified_mode); 1271 1272 #if !(defined LINUX || defined BSD || defined _WINDOWS) 1273 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N' 1274 // is not supported as mode in fopen 1275 if (file != NULL) { 1276 int fd = fileno(file); 1277 if (fd != -1) { 1278 int fd_flags = fcntl(fd, F_GETFD); 1279 if (fd_flags != -1) { 1280 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC); 1281 } 1282 } 1283 } 1284 #endif 1285 1286 return file; 1287 } 1288 1289 bool os::set_boot_path(char fileSep, char pathSep) { 1290 const char* home = Arguments::get_java_home(); 1291 int home_len = (int)strlen(home); 1292 1293 struct stat st; 1294 1295 // modular image if "modules" jimage exists 1296 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep); 1297 if (jimage == NULL) return false; 1298 bool has_jimage = (os::stat(jimage, &st) == 0); 1299 if (has_jimage) { 1300 Arguments::set_sysclasspath(jimage, true); 1301 FREE_C_HEAP_ARRAY(char, jimage); 1302 return true; 1303 } 1304 FREE_C_HEAP_ARRAY(char, jimage); 1305 1306 // check if developer build with exploded modules 1307 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep); 1308 if (base_classes == NULL) return false; 1309 if (os::stat(base_classes, &st) == 0) { 1310 Arguments::set_sysclasspath(base_classes, false); 1311 FREE_C_HEAP_ARRAY(char, base_classes); 1312 return true; 1313 } 1314 FREE_C_HEAP_ARRAY(char, base_classes); 1315 1316 return false; 1317 } 1318 1319 bool os::file_exists(const char* filename) { 1320 struct stat statbuf; 1321 if (filename == NULL || strlen(filename) == 0) { 1322 return false; 1323 } 1324 return os::stat(filename, &statbuf) == 0; 1325 } 1326 1327 // Splits a path, based on its separator, the number of 1328 // elements is returned back in "elements". 1329 // file_name_length is used as a modifier for each path's 1330 // length when compared to JVM_MAXPATHLEN. So if you know 1331 // each returned path will have something appended when 1332 // in use, you can pass the length of that in 1333 // file_name_length, to ensure we detect if any path 1334 // exceeds the maximum path length once prepended onto 1335 // the sub-path/file name. 1336 // It is the callers responsibility to: 1337 // a> check the value of "elements", which may be 0. 1338 // b> ignore any empty path elements 1339 // c> free up the data. 1340 char** os::split_path(const char* path, size_t* elements, size_t file_name_length) { 1341 *elements = (size_t)0; 1342 if (path == NULL || strlen(path) == 0 || file_name_length == (size_t)NULL) { 1343 return NULL; 1344 } 1345 const char psepchar = *os::path_separator(); 1346 char* inpath = NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1347 strcpy(inpath, path); 1348 size_t count = 1; 1349 char* p = strchr(inpath, psepchar); 1350 // Get a count of elements to allocate memory 1351 while (p != NULL) { 1352 count++; 1353 p++; 1354 p = strchr(p, psepchar); 1355 } 1356 1357 char** opath = NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1358 1359 // do the actual splitting 1360 p = inpath; 1361 for (size_t i = 0 ; i < count ; i++) { 1362 size_t len = strcspn(p, os::path_separator()); 1363 if (len + file_name_length > JVM_MAXPATHLEN) { 1364 // release allocated storage before exiting the vm 1365 free_array_of_char_arrays(opath, i++); 1366 vm_exit_during_initialization("The VM tried to use a path that exceeds the maximum path length for " 1367 "this system. Review path-containing parameters and properties, such as " 1368 "sun.boot.library.path, to identify potential sources for this path."); 1369 } 1370 // allocate the string and add terminator storage 1371 char* s = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1372 strncpy(s, p, len); 1373 s[len] = '\0'; 1374 opath[i] = s; 1375 p += len + 1; 1376 } 1377 FREE_C_HEAP_ARRAY(char, inpath); 1378 *elements = count; 1379 return opath; 1380 } 1381 1382 // Returns true if the current stack pointer is above the stack shadow 1383 // pages, false otherwise. 1384 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) { 1385 if (!thread->is_Java_thread()) return false; 1386 // Check if we have StackShadowPages above the guard zone. This parameter 1387 // is dependent on the depth of the maximum VM call stack possible from 1388 // the handler for stack overflow. 'instanceof' in the stack overflow 1389 // handler or a println uses at least 8k stack of VM and native code 1390 // respectively. 1391 const int framesize_in_bytes = 1392 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1393 1394 address limit = JavaThread::cast(thread)->stack_overflow_state()->shadow_zone_safe_limit(); 1395 return sp > (limit + framesize_in_bytes); 1396 } 1397 1398 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1399 assert(min_pages > 0, "sanity"); 1400 if (UseLargePages) { 1401 const size_t max_page_size = region_size / min_pages; 1402 1403 for (size_t page_size = page_sizes().largest(); page_size != 0; 1404 page_size = page_sizes().next_smaller(page_size)) { 1405 if (page_size <= max_page_size) { 1406 if (!must_be_aligned || is_aligned(region_size, page_size)) { 1407 return page_size; 1408 } 1409 } 1410 } 1411 } 1412 1413 return vm_page_size(); 1414 } 1415 1416 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1417 return page_size_for_region(region_size, min_pages, true); 1418 } 1419 1420 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1421 return page_size_for_region(region_size, min_pages, false); 1422 } 1423 1424 #ifndef MAX_PATH 1425 #define MAX_PATH (2 * K) 1426 #endif 1427 1428 void os::pause() { 1429 char filename[MAX_PATH]; 1430 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 1431 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile); 1432 } else { 1433 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 1434 } 1435 1436 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 1437 if (fd != -1) { 1438 struct stat buf; 1439 ::close(fd); 1440 while (::stat(filename, &buf) == 0) { 1441 #if defined(_WINDOWS) 1442 Sleep(100); 1443 #else 1444 (void)::poll(NULL, 0, 100); 1445 #endif 1446 } 1447 } else { 1448 jio_fprintf(stderr, 1449 "Could not open pause file '%s', continuing immediately.\n", filename); 1450 } 1451 } 1452 1453 static const char* errno_to_string (int e, bool short_text) { 1454 #define ALL_SHARED_ENUMS(X) \ 1455 X(E2BIG, "Argument list too long") \ 1456 X(EACCES, "Permission denied") \ 1457 X(EADDRINUSE, "Address in use") \ 1458 X(EADDRNOTAVAIL, "Address not available") \ 1459 X(EAFNOSUPPORT, "Address family not supported") \ 1460 X(EAGAIN, "Resource unavailable, try again") \ 1461 X(EALREADY, "Connection already in progress") \ 1462 X(EBADF, "Bad file descriptor") \ 1463 X(EBADMSG, "Bad message") \ 1464 X(EBUSY, "Device or resource busy") \ 1465 X(ECANCELED, "Operation canceled") \ 1466 X(ECHILD, "No child processes") \ 1467 X(ECONNABORTED, "Connection aborted") \ 1468 X(ECONNREFUSED, "Connection refused") \ 1469 X(ECONNRESET, "Connection reset") \ 1470 X(EDEADLK, "Resource deadlock would occur") \ 1471 X(EDESTADDRREQ, "Destination address required") \ 1472 X(EDOM, "Mathematics argument out of domain of function") \ 1473 X(EEXIST, "File exists") \ 1474 X(EFAULT, "Bad address") \ 1475 X(EFBIG, "File too large") \ 1476 X(EHOSTUNREACH, "Host is unreachable") \ 1477 X(EIDRM, "Identifier removed") \ 1478 X(EILSEQ, "Illegal byte sequence") \ 1479 X(EINPROGRESS, "Operation in progress") \ 1480 X(EINTR, "Interrupted function") \ 1481 X(EINVAL, "Invalid argument") \ 1482 X(EIO, "I/O error") \ 1483 X(EISCONN, "Socket is connected") \ 1484 X(EISDIR, "Is a directory") \ 1485 X(ELOOP, "Too many levels of symbolic links") \ 1486 X(EMFILE, "Too many open files") \ 1487 X(EMLINK, "Too many links") \ 1488 X(EMSGSIZE, "Message too large") \ 1489 X(ENAMETOOLONG, "Filename too long") \ 1490 X(ENETDOWN, "Network is down") \ 1491 X(ENETRESET, "Connection aborted by network") \ 1492 X(ENETUNREACH, "Network unreachable") \ 1493 X(ENFILE, "Too many files open in system") \ 1494 X(ENOBUFS, "No buffer space available") \ 1495 X(ENODATA, "No message is available on the STREAM head read queue") \ 1496 X(ENODEV, "No such device") \ 1497 X(ENOENT, "No such file or directory") \ 1498 X(ENOEXEC, "Executable file format error") \ 1499 X(ENOLCK, "No locks available") \ 1500 X(ENOLINK, "Reserved") \ 1501 X(ENOMEM, "Not enough space") \ 1502 X(ENOMSG, "No message of the desired type") \ 1503 X(ENOPROTOOPT, "Protocol not available") \ 1504 X(ENOSPC, "No space left on device") \ 1505 X(ENOSR, "No STREAM resources") \ 1506 X(ENOSTR, "Not a STREAM") \ 1507 X(ENOSYS, "Function not supported") \ 1508 X(ENOTCONN, "The socket is not connected") \ 1509 X(ENOTDIR, "Not a directory") \ 1510 X(ENOTEMPTY, "Directory not empty") \ 1511 X(ENOTSOCK, "Not a socket") \ 1512 X(ENOTSUP, "Not supported") \ 1513 X(ENOTTY, "Inappropriate I/O control operation") \ 1514 X(ENXIO, "No such device or address") \ 1515 X(EOPNOTSUPP, "Operation not supported on socket") \ 1516 X(EOVERFLOW, "Value too large to be stored in data type") \ 1517 X(EPERM, "Operation not permitted") \ 1518 X(EPIPE, "Broken pipe") \ 1519 X(EPROTO, "Protocol error") \ 1520 X(EPROTONOSUPPORT, "Protocol not supported") \ 1521 X(EPROTOTYPE, "Protocol wrong type for socket") \ 1522 X(ERANGE, "Result too large") \ 1523 X(EROFS, "Read-only file system") \ 1524 X(ESPIPE, "Invalid seek") \ 1525 X(ESRCH, "No such process") \ 1526 X(ETIME, "Stream ioctl() timeout") \ 1527 X(ETIMEDOUT, "Connection timed out") \ 1528 X(ETXTBSY, "Text file busy") \ 1529 X(EWOULDBLOCK, "Operation would block") \ 1530 X(EXDEV, "Cross-device link") 1531 1532 #define DEFINE_ENTRY(e, text) { e, #e, text }, 1533 1534 static const struct { 1535 int v; 1536 const char* short_text; 1537 const char* long_text; 1538 } table [] = { 1539 1540 ALL_SHARED_ENUMS(DEFINE_ENTRY) 1541 1542 // The following enums are not defined on all platforms. 1543 #ifdef ESTALE 1544 DEFINE_ENTRY(ESTALE, "Reserved") 1545 #endif 1546 #ifdef EDQUOT 1547 DEFINE_ENTRY(EDQUOT, "Reserved") 1548 #endif 1549 #ifdef EMULTIHOP 1550 DEFINE_ENTRY(EMULTIHOP, "Reserved") 1551 #endif 1552 1553 // End marker. 1554 { -1, "Unknown errno", "Unknown error" } 1555 1556 }; 1557 1558 #undef DEFINE_ENTRY 1559 #undef ALL_FLAGS 1560 1561 int i = 0; 1562 while (table[i].v != -1 && table[i].v != e) { 1563 i ++; 1564 } 1565 1566 return short_text ? table[i].short_text : table[i].long_text; 1567 1568 } 1569 1570 const char* os::strerror(int e) { 1571 return errno_to_string(e, false); 1572 } 1573 1574 const char* os::errno_name(int e) { 1575 return errno_to_string(e, true); 1576 } 1577 1578 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size) 1579 1580 void os::trace_page_sizes(const char* str, 1581 const size_t region_min_size, 1582 const size_t region_max_size, 1583 const size_t page_size, 1584 const char* base, 1585 const size_t size) { 1586 1587 log_info(pagesize)("%s: " 1588 " min=" SIZE_FORMAT "%s" 1589 " max=" SIZE_FORMAT "%s" 1590 " base=" PTR_FORMAT 1591 " page_size=" SIZE_FORMAT "%s" 1592 " size=" SIZE_FORMAT "%s", 1593 str, 1594 trace_page_size_params(region_min_size), 1595 trace_page_size_params(region_max_size), 1596 p2i(base), 1597 trace_page_size_params(page_size), 1598 trace_page_size_params(size)); 1599 } 1600 1601 void os::trace_page_sizes_for_requested_size(const char* str, 1602 const size_t requested_size, 1603 const size_t page_size, 1604 const size_t alignment, 1605 const char* base, 1606 const size_t size) { 1607 1608 log_info(pagesize)("%s:" 1609 " req_size=" SIZE_FORMAT "%s" 1610 " base=" PTR_FORMAT 1611 " page_size=" SIZE_FORMAT "%s" 1612 " alignment=" SIZE_FORMAT "%s" 1613 " size=" SIZE_FORMAT "%s", 1614 str, 1615 trace_page_size_params(requested_size), 1616 p2i(base), 1617 trace_page_size_params(page_size), 1618 trace_page_size_params(alignment), 1619 trace_page_size_params(size)); 1620 } 1621 1622 1623 // This is the working definition of a server class machine: 1624 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1625 // because the graphics memory (?) sometimes masks physical memory. 1626 // If you want to change the definition of a server class machine 1627 // on some OS or platform, e.g., >=4GB on Windows platforms, 1628 // then you'll have to parameterize this method based on that state, 1629 // as was done for logical processors here, or replicate and 1630 // specialize this method for each platform. (Or fix os to have 1631 // some inheritance structure and use subclassing. Sigh.) 1632 // If you want some platform to always or never behave as a server 1633 // class machine, change the setting of AlwaysActAsServerClassMachine 1634 // and NeverActAsServerClassMachine in globals*.hpp. 1635 bool os::is_server_class_machine() { 1636 // First check for the early returns 1637 if (NeverActAsServerClassMachine) { 1638 return false; 1639 } 1640 if (AlwaysActAsServerClassMachine) { 1641 return true; 1642 } 1643 // Then actually look at the machine 1644 bool result = false; 1645 const unsigned int server_processors = 2; 1646 const julong server_memory = 2UL * G; 1647 // We seem not to get our full complement of memory. 1648 // We allow some part (1/8?) of the memory to be "missing", 1649 // based on the sizes of DIMMs, and maybe graphics cards. 1650 const julong missing_memory = 256UL * M; 1651 1652 /* Is this a server class machine? */ 1653 if ((os::active_processor_count() >= (int)server_processors) && 1654 (os::physical_memory() >= (server_memory - missing_memory))) { 1655 const unsigned int logical_processors = 1656 VM_Version::logical_processors_per_package(); 1657 if (logical_processors > 1) { 1658 const unsigned int physical_packages = 1659 os::active_processor_count() / logical_processors; 1660 if (physical_packages >= server_processors) { 1661 result = true; 1662 } 1663 } else { 1664 result = true; 1665 } 1666 } 1667 return result; 1668 } 1669 1670 void os::initialize_initial_active_processor_count() { 1671 assert(_initial_active_processor_count == 0, "Initial active processor count already set."); 1672 _initial_active_processor_count = active_processor_count(); 1673 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count); 1674 } 1675 1676 void os::SuspendedThreadTask::run() { 1677 internal_do_task(); 1678 _done = true; 1679 } 1680 1681 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1682 return os::pd_create_stack_guard_pages(addr, bytes); 1683 } 1684 1685 char* os::reserve_memory(size_t bytes, bool executable, MEMFLAGS flags) { 1686 char* result = pd_reserve_memory(bytes, executable); 1687 if (result != NULL) { 1688 MemTracker::record_virtual_memory_reserve(result, bytes, CALLER_PC); 1689 if (flags != mtOther) { 1690 MemTracker::record_virtual_memory_type(result, flags); 1691 } 1692 } 1693 1694 return result; 1695 } 1696 1697 char* os::attempt_reserve_memory_at(char* addr, size_t bytes, bool executable) { 1698 char* result = pd_attempt_reserve_memory_at(addr, bytes, executable); 1699 if (result != NULL) { 1700 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1701 } else { 1702 log_debug(os)("Attempt to reserve memory at " INTPTR_FORMAT " for " 1703 SIZE_FORMAT " bytes failed, errno %d", p2i(addr), bytes, get_last_error()); 1704 } 1705 return result; 1706 } 1707 1708 static void assert_nonempty_range(const char* addr, size_t bytes) { 1709 assert(addr != nullptr && bytes > 0, "invalid range [" PTR_FORMAT ", " PTR_FORMAT ")", 1710 p2i(addr), p2i(addr) + bytes); 1711 } 1712 1713 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1714 assert_nonempty_range(addr, bytes); 1715 bool res = pd_commit_memory(addr, bytes, executable); 1716 if (res) { 1717 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1718 } 1719 return res; 1720 } 1721 1722 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1723 bool executable) { 1724 assert_nonempty_range(addr, size); 1725 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1726 if (res) { 1727 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1728 } 1729 return res; 1730 } 1731 1732 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1733 const char* mesg) { 1734 assert_nonempty_range(addr, bytes); 1735 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1736 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1737 } 1738 1739 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1740 bool executable, const char* mesg) { 1741 assert_nonempty_range(addr, size); 1742 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1743 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1744 } 1745 1746 bool os::uncommit_memory(char* addr, size_t bytes, bool executable) { 1747 assert_nonempty_range(addr, bytes); 1748 bool res; 1749 if (MemTracker::enabled()) { 1750 Tracker tkr(Tracker::uncommit); 1751 res = pd_uncommit_memory(addr, bytes, executable); 1752 if (res) { 1753 tkr.record((address)addr, bytes); 1754 } 1755 } else { 1756 res = pd_uncommit_memory(addr, bytes, executable); 1757 } 1758 return res; 1759 } 1760 1761 bool os::release_memory(char* addr, size_t bytes) { 1762 assert_nonempty_range(addr, bytes); 1763 bool res; 1764 if (MemTracker::enabled()) { 1765 // Note: Tracker contains a ThreadCritical. 1766 Tracker tkr(Tracker::release); 1767 res = pd_release_memory(addr, bytes); 1768 if (res) { 1769 tkr.record((address)addr, bytes); 1770 } 1771 } else { 1772 res = pd_release_memory(addr, bytes); 1773 } 1774 if (!res) { 1775 log_info(os)("os::release_memory failed (" PTR_FORMAT ", " SIZE_FORMAT ")", p2i(addr), bytes); 1776 } 1777 return res; 1778 } 1779 1780 // Prints all mappings 1781 void os::print_memory_mappings(outputStream* st) { 1782 os::print_memory_mappings(nullptr, (size_t)-1, st); 1783 } 1784 1785 // Pretouching must use a store, not just a load. On many OSes loads from 1786 // fresh memory would be satisfied from a single mapped page containing all 1787 // zeros. We need to store something to each page to get them backed by 1788 // their own memory, which is the effect we want here. An atomic add of 1789 // zero is used instead of a simple store, allowing the memory to be used 1790 // while pretouch is in progress, rather than requiring users of the memory 1791 // to wait until the entire range has been touched. This is technically 1792 // a UB data race, but doesn't cause any problems for us. 1793 void os::pretouch_memory(void* start, void* end, size_t page_size) { 1794 assert(start <= end, "invalid range: " PTR_FORMAT " -> " PTR_FORMAT, p2i(start), p2i(end)); 1795 assert(is_power_of_2(page_size), "page size misaligned: %zu", page_size); 1796 assert(page_size >= sizeof(int), "page size too small: %zu", page_size); 1797 if (start < end) { 1798 // We're doing concurrent-safe touch and memory state has page 1799 // granularity, so we can touch anywhere in a page. Touch at the 1800 // beginning of each page to simplify iteration. 1801 char* cur = static_cast<char*>(align_down(start, page_size)); 1802 void* last = align_down(static_cast<char*>(end) - 1, page_size); 1803 assert(cur <= last, "invariant"); 1804 // Iterate from first page through last (inclusive), being careful to 1805 // avoid overflow if the last page abuts the end of the address range. 1806 for ( ; true; cur += page_size) { 1807 Atomic::add(reinterpret_cast<int*>(cur), 0, memory_order_relaxed); 1808 if (cur >= last) break; 1809 } 1810 } 1811 } 1812 1813 char* os::map_memory_to_file(size_t bytes, int file_desc) { 1814 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(), 1815 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file. 1816 // On all current implementations NULL is interpreted as any available address. 1817 char* result = os::map_memory_to_file(NULL /* addr */, bytes, file_desc); 1818 if (result != NULL) { 1819 MemTracker::record_virtual_memory_reserve_and_commit(result, bytes, CALLER_PC); 1820 } 1821 return result; 1822 } 1823 1824 char* os::attempt_map_memory_to_file_at(char* addr, size_t bytes, int file_desc) { 1825 char* result = pd_attempt_map_memory_to_file_at(addr, bytes, file_desc); 1826 if (result != NULL) { 1827 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1828 } 1829 return result; 1830 } 1831 1832 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1833 char *addr, size_t bytes, bool read_only, 1834 bool allow_exec, MEMFLAGS flags) { 1835 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1836 if (result != NULL) { 1837 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC, flags); 1838 } 1839 return result; 1840 } 1841 1842 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1843 char *addr, size_t bytes, bool read_only, 1844 bool allow_exec) { 1845 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1846 read_only, allow_exec); 1847 } 1848 1849 bool os::unmap_memory(char *addr, size_t bytes) { 1850 bool result; 1851 if (MemTracker::enabled()) { 1852 Tracker tkr(Tracker::release); 1853 result = pd_unmap_memory(addr, bytes); 1854 if (result) { 1855 tkr.record((address)addr, bytes); 1856 } 1857 } else { 1858 result = pd_unmap_memory(addr, bytes); 1859 } 1860 return result; 1861 } 1862 1863 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1864 pd_free_memory(addr, bytes, alignment_hint); 1865 } 1866 1867 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1868 pd_realign_memory(addr, bytes, alignment_hint); 1869 } 1870 1871 char* os::reserve_memory_special(size_t size, size_t alignment, size_t page_size, 1872 char* addr, bool executable) { 1873 1874 assert(is_aligned(addr, alignment), "Unaligned request address"); 1875 1876 char* result = pd_reserve_memory_special(size, alignment, page_size, addr, executable); 1877 if (result != NULL) { 1878 // The memory is committed 1879 MemTracker::record_virtual_memory_reserve_and_commit((address)result, size, CALLER_PC); 1880 } 1881 1882 return result; 1883 } 1884 1885 bool os::release_memory_special(char* addr, size_t bytes) { 1886 bool res; 1887 if (MemTracker::enabled()) { 1888 // Note: Tracker contains a ThreadCritical. 1889 Tracker tkr(Tracker::release); 1890 res = pd_release_memory_special(addr, bytes); 1891 if (res) { 1892 tkr.record((address)addr, bytes); 1893 } 1894 } else { 1895 res = pd_release_memory_special(addr, bytes); 1896 } 1897 return res; 1898 } 1899 1900 #ifndef _WINDOWS 1901 /* try to switch state from state "from" to state "to" 1902 * returns the state set after the method is complete 1903 */ 1904 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1905 os::SuspendResume::State to) 1906 { 1907 os::SuspendResume::State result = Atomic::cmpxchg(&_state, from, to); 1908 if (result == from) { 1909 // success 1910 return to; 1911 } 1912 return result; 1913 } 1914 #endif 1915 1916 // Convenience wrapper around naked_short_sleep to allow for longer sleep 1917 // times. Only for use by non-JavaThreads. 1918 void os::naked_sleep(jlong millis) { 1919 assert(!Thread::current()->is_Java_thread(), "not for use by JavaThreads"); 1920 const jlong limit = 999; 1921 while (millis > limit) { 1922 naked_short_sleep(limit); 1923 millis -= limit; 1924 } 1925 naked_short_sleep(millis); 1926 } 1927 1928 1929 ////// Implementation of PageSizes 1930 1931 void os::PageSizes::add(size_t page_size) { 1932 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size); 1933 _v |= page_size; 1934 } 1935 1936 bool os::PageSizes::contains(size_t page_size) const { 1937 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size); 1938 return (_v & page_size) != 0; 1939 } 1940 1941 size_t os::PageSizes::next_smaller(size_t page_size) const { 1942 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size); 1943 size_t v2 = _v & (page_size - 1); 1944 if (v2 == 0) { 1945 return 0; 1946 } 1947 return round_down_power_of_2(v2); 1948 } 1949 1950 size_t os::PageSizes::next_larger(size_t page_size) const { 1951 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size); 1952 if (page_size == max_power_of_2<size_t>()) { // Shift by 32/64 would be UB 1953 return 0; 1954 } 1955 // Remove current and smaller page sizes 1956 size_t v2 = _v & ~(page_size + (page_size - 1)); 1957 if (v2 == 0) { 1958 return 0; 1959 } 1960 return (size_t)1 << count_trailing_zeros(v2); 1961 } 1962 1963 size_t os::PageSizes::largest() const { 1964 const size_t max = max_power_of_2<size_t>(); 1965 if (contains(max)) { 1966 return max; 1967 } 1968 return next_smaller(max); 1969 } 1970 1971 size_t os::PageSizes::smallest() const { 1972 // Strictly speaking the set should not contain sizes < os::vm_page_size(). 1973 // But this is not enforced. 1974 return next_larger(1); 1975 } 1976 1977 void os::PageSizes::print_on(outputStream* st) const { 1978 bool first = true; 1979 for (size_t sz = smallest(); sz != 0; sz = next_larger(sz)) { 1980 if (first) { 1981 first = false; 1982 } else { 1983 st->print_raw(", "); 1984 } 1985 if (sz < M) { 1986 st->print(SIZE_FORMAT "k", sz / K); 1987 } else if (sz < G) { 1988 st->print(SIZE_FORMAT "M", sz / M); 1989 } else { 1990 st->print(SIZE_FORMAT "G", sz / G); 1991 } 1992 } 1993 if (first) { 1994 st->print("empty"); 1995 } 1996 }