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 "classfile/classLoader.hpp" 27 #include "classfile/javaClasses.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/icBuffer.hpp" 31 #include "code/vtableStubs.hpp" 32 #include "gc_implementation/shared/vmGCOperations.hpp" 33 #include "interpreter/interpreter.hpp" 34 #include "memory/allocation.inline.hpp" 35 #ifdef ASSERT 36 #include "memory/guardedMemory.hpp" 37 #endif 38 #include "oops/oop.inline.hpp" 39 #include "prims/jvm.h" 40 #include "prims/jvm_misc.hpp" 41 #include "prims/privilegedStack.hpp" 42 #include "runtime/arguments.hpp" 43 #include "runtime/frame.inline.hpp" 44 #include "runtime/interfaceSupport.hpp" 45 #include "runtime/java.hpp" 46 #include "runtime/javaCalls.hpp" 47 #include "runtime/mutexLocker.hpp" 48 #include "runtime/os.hpp" 49 #include "runtime/stubRoutines.hpp" 50 #include "runtime/thread.inline.hpp" 51 #include "services/attachListener.hpp" 52 #include "services/nmtCommon.hpp" 53 #include "services/mallocTracker.hpp" 54 #include "services/memTracker.hpp" 55 #include "services/threadService.hpp" 56 #include "utilities/defaultStream.hpp" 57 #include "utilities/events.hpp" 58 #ifdef TARGET_OS_FAMILY_linux 59 # include "os_linux.inline.hpp" 60 #endif 61 #ifdef TARGET_OS_FAMILY_solaris 62 # include "os_solaris.inline.hpp" 63 #endif 64 #ifdef TARGET_OS_FAMILY_windows 65 # include "os_windows.inline.hpp" 66 #endif 67 #ifdef TARGET_OS_FAMILY_bsd 68 # include "os_bsd.inline.hpp" 69 #endif 70 71 # include <signal.h> 72 73 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 74 75 OSThread* os::_starting_thread = NULL; 76 address os::_polling_page = NULL; 77 volatile int32_t* os::_mem_serialize_page = NULL; 78 uintptr_t os::_serialize_page_mask = 0; 79 long os::_rand_seed = 1; 80 int os::_processor_count = 0; 81 int os::_initial_active_processor_count = 0; 82 size_t os::_page_sizes[os::page_sizes_max]; 83 84 #ifndef PRODUCT 85 julong os::num_mallocs = 0; // # of calls to malloc/realloc 86 julong os::alloc_bytes = 0; // # of bytes allocated 87 julong os::num_frees = 0; // # of calls to free 88 julong os::free_bytes = 0; // # of bytes freed 89 #endif 90 91 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords 92 93 void os_init_globals() { 94 // Called from init_globals(). 95 // See Threads::create_vm() in thread.cpp, and init.cpp. 96 os::init_globals(); 97 } 98 99 static time_t get_timezone(const struct tm* time_struct) { 100 #if defined(_ALLBSD_SOURCE) 101 return time_struct->tm_gmtoff; 102 #elif defined(_WINDOWS) 103 long zone; 104 _get_timezone(&zone); 105 return static_cast<time_t>(zone); 106 #else 107 return timezone; 108 #endif 109 } 110 111 int os::snprintf(char* buf, size_t len, const char* fmt, ...) { 112 va_list args; 113 va_start(args, fmt); 114 int result = os::vsnprintf(buf, len, fmt, args); 115 va_end(args); 116 return result; 117 } 118 119 // Fill in buffer with current local time as an ISO-8601 string. 120 // E.g., yyyy-mm-ddThh:mm:ss-zzzz. 121 // Returns buffer, or NULL if it failed. 122 // This would mostly be a call to 123 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 124 // except that on Windows the %z behaves badly, so we do it ourselves. 125 // Also, people wanted milliseconds on there, 126 // and strftime doesn't do milliseconds. 127 char* os::iso8601_time(char* buffer, size_t buffer_length) { 128 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 129 // 1 2 130 // 12345678901234567890123456789 131 static const char* iso8601_format = 132 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; 133 static const size_t needed_buffer = 29; 134 135 // Sanity check the arguments 136 if (buffer == NULL) { 137 assert(false, "NULL buffer"); 138 return NULL; 139 } 140 if (buffer_length < needed_buffer) { 141 assert(false, "buffer_length too small"); 142 return NULL; 143 } 144 // Get the current time 145 jlong milliseconds_since_19700101 = javaTimeMillis(); 146 const int milliseconds_per_microsecond = 1000; 147 const time_t seconds_since_19700101 = 148 milliseconds_since_19700101 / milliseconds_per_microsecond; 149 const int milliseconds_after_second = 150 milliseconds_since_19700101 % milliseconds_per_microsecond; 151 // Convert the time value to a tm and timezone variable 152 struct tm time_struct; 153 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 154 assert(false, "Failed localtime_pd"); 155 return NULL; 156 } 157 const time_t zone = get_timezone(&time_struct); 158 159 // If daylight savings time is in effect, 160 // we are 1 hour East of our time zone 161 const time_t seconds_per_minute = 60; 162 const time_t minutes_per_hour = 60; 163 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 164 time_t UTC_to_local = zone; 165 if (time_struct.tm_isdst > 0) { 166 UTC_to_local = UTC_to_local - seconds_per_hour; 167 } 168 // Compute the time zone offset. 169 // localtime_pd() sets timezone to the difference (in seconds) 170 // between UTC and and local time. 171 // ISO 8601 says we need the difference between local time and UTC, 172 // we change the sign of the localtime_pd() result. 173 const time_t local_to_UTC = -(UTC_to_local); 174 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 175 char sign_local_to_UTC = '+'; 176 time_t abs_local_to_UTC = local_to_UTC; 177 if (local_to_UTC < 0) { 178 sign_local_to_UTC = '-'; 179 abs_local_to_UTC = -(abs_local_to_UTC); 180 } 181 // Convert time zone offset seconds to hours and minutes. 182 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 183 const time_t zone_min = 184 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 185 186 // Print an ISO 8601 date and time stamp into the buffer 187 const int year = 1900 + time_struct.tm_year; 188 const int month = 1 + time_struct.tm_mon; 189 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, 190 year, 191 month, 192 time_struct.tm_mday, 193 time_struct.tm_hour, 194 time_struct.tm_min, 195 time_struct.tm_sec, 196 milliseconds_after_second, 197 sign_local_to_UTC, 198 zone_hours, 199 zone_min); 200 if (printed == 0) { 201 assert(false, "Failed jio_printf"); 202 return NULL; 203 } 204 return buffer; 205 } 206 207 OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 208 #ifdef ASSERT 209 if (!(!thread->is_Java_thread() || 210 Thread::current() == thread || 211 Threads_lock->owned_by_self() 212 || thread->is_Compiler_thread() 213 )) { 214 assert(false, "possibility of dangling Thread pointer"); 215 } 216 #endif 217 218 if (p >= MinPriority && p <= MaxPriority) { 219 int priority = java_to_os_priority[p]; 220 return set_native_priority(thread, priority); 221 } else { 222 assert(false, "Should not happen"); 223 return OS_ERR; 224 } 225 } 226 227 // The mapping from OS priority back to Java priority may be inexact because 228 // Java priorities can map M:1 with native priorities. If you want the definite 229 // Java priority then use JavaThread::java_priority() 230 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 231 int p; 232 int os_prio; 233 OSReturn ret = get_native_priority(thread, &os_prio); 234 if (ret != OS_OK) return ret; 235 236 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 237 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 238 } else { 239 // niceness values are in reverse order 240 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 241 } 242 priority = (ThreadPriority)p; 243 return OS_OK; 244 } 245 246 247 // --------------------- sun.misc.Signal (optional) --------------------- 248 249 250 // SIGBREAK is sent by the keyboard to query the VM state 251 #ifndef SIGBREAK 252 #define SIGBREAK SIGQUIT 253 #endif 254 255 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 256 257 258 static void signal_thread_entry(JavaThread* thread, TRAPS) { 259 os::set_priority(thread, NearMaxPriority); 260 while (true) { 261 int sig; 262 { 263 // FIXME : Currently we have not decieded what should be the status 264 // for this java thread blocked here. Once we decide about 265 // that we should fix this. 266 sig = os::signal_wait(); 267 } 268 if (sig == os::sigexitnum_pd()) { 269 // Terminate the signal thread 270 return; 271 } 272 273 switch (sig) { 274 case SIGBREAK: { 275 // Check if the signal is a trigger to start the Attach Listener - in that 276 // case don't print stack traces. 277 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 278 continue; 279 } 280 // Print stack traces 281 // Any SIGBREAK operations added here should make sure to flush 282 // the output stream (e.g. tty->flush()) after output. See 4803766. 283 // Each module also prints an extra carriage return after its output. 284 VM_PrintThreads op; 285 VMThread::execute(&op); 286 VM_PrintJNI jni_op; 287 VMThread::execute(&jni_op); 288 VM_FindDeadlocks op1(tty); 289 VMThread::execute(&op1); 290 Universe::print_heap_at_SIGBREAK(); 291 if (PrintClassHistogram) { 292 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */); 293 VMThread::execute(&op1); 294 } 295 if (JvmtiExport::should_post_data_dump()) { 296 JvmtiExport::post_data_dump(); 297 } 298 break; 299 } 300 default: { 301 // Dispatch the signal to java 302 HandleMark hm(THREAD); 303 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 304 KlassHandle klass (THREAD, k); 305 if (klass.not_null()) { 306 JavaValue result(T_VOID); 307 JavaCallArguments args; 308 args.push_int(sig); 309 JavaCalls::call_static( 310 &result, 311 klass, 312 vmSymbols::dispatch_name(), 313 vmSymbols::int_void_signature(), 314 &args, 315 THREAD 316 ); 317 } 318 if (HAS_PENDING_EXCEPTION) { 319 // tty is initialized early so we don't expect it to be null, but 320 // if it is we can't risk doing an initialization that might 321 // trigger additional out-of-memory conditions 322 if (tty != NULL) { 323 char klass_name[256]; 324 char tmp_sig_name[16]; 325 const char* sig_name = "UNKNOWN"; 326 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 327 name()->as_klass_external_name(klass_name, 256); 328 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 329 sig_name = tmp_sig_name; 330 warning("Exception %s occurred dispatching signal %s to handler" 331 "- the VM may need to be forcibly terminated", 332 klass_name, sig_name ); 333 } 334 CLEAR_PENDING_EXCEPTION; 335 } 336 } 337 } 338 } 339 } 340 341 void os::init_before_ergo() { 342 initialize_initial_active_processor_count(); 343 // We need to initialize large page support here because ergonomics takes some 344 // decisions depending on large page support and the calculated large page size. 345 large_page_init(); 346 347 // VM version initialization identifies some characteristics of the 348 // the platform that are used during ergonomic decisions. 349 VM_Version::init_before_ergo(); 350 } 351 352 void os::signal_init() { 353 if (!ReduceSignalUsage) { 354 // Setup JavaThread for processing signals 355 EXCEPTION_MARK; 356 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 357 instanceKlassHandle klass (THREAD, k); 358 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 359 360 const char thread_name[] = "Signal Dispatcher"; 361 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 362 363 // Initialize thread_oop to put it into the system threadGroup 364 Handle thread_group (THREAD, Universe::system_thread_group()); 365 JavaValue result(T_VOID); 366 JavaCalls::call_special(&result, thread_oop, 367 klass, 368 vmSymbols::object_initializer_name(), 369 vmSymbols::threadgroup_string_void_signature(), 370 thread_group, 371 string, 372 CHECK); 373 374 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 375 JavaCalls::call_special(&result, 376 thread_group, 377 group, 378 vmSymbols::add_method_name(), 379 vmSymbols::thread_void_signature(), 380 thread_oop, // ARG 1 381 CHECK); 382 383 os::signal_init_pd(); 384 385 { MutexLocker mu(Threads_lock); 386 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 387 388 // At this point it may be possible that no osthread was created for the 389 // JavaThread due to lack of memory. We would have to throw an exception 390 // in that case. However, since this must work and we do not allow 391 // exceptions anyway, check and abort if this fails. 392 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 393 vm_exit_during_initialization("java.lang.OutOfMemoryError", 394 "unable to create new native thread"); 395 } 396 397 java_lang_Thread::set_thread(thread_oop(), signal_thread); 398 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 399 java_lang_Thread::set_daemon(thread_oop()); 400 401 signal_thread->set_threadObj(thread_oop()); 402 Threads::add(signal_thread); 403 Thread::start(signal_thread); 404 } 405 // Handle ^BREAK 406 os::signal(SIGBREAK, os::user_handler()); 407 } 408 } 409 410 411 void os::terminate_signal_thread() { 412 if (!ReduceSignalUsage) 413 signal_notify(sigexitnum_pd()); 414 } 415 416 417 // --------------------- loading libraries --------------------- 418 419 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 420 extern struct JavaVM_ main_vm; 421 422 static void* _native_java_library = NULL; 423 424 void* os::native_java_library() { 425 if (_native_java_library == NULL) { 426 char buffer[JVM_MAXPATHLEN]; 427 char ebuf[1024]; 428 429 // Try to load verify dll first. In 1.3 java dll depends on it and is not 430 // always able to find it when the loading executable is outside the JDK. 431 // In order to keep working with 1.2 we ignore any loading errors. 432 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 433 "verify")) { 434 dll_load(buffer, ebuf, sizeof(ebuf)); 435 } 436 437 // Load java dll 438 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 439 "java")) { 440 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 441 } 442 if (_native_java_library == NULL) { 443 vm_exit_during_initialization("Unable to load native library", ebuf); 444 } 445 446 #if defined(__OpenBSD__) 447 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 448 // ignore errors 449 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 450 "net")) { 451 dll_load(buffer, ebuf, sizeof(ebuf)); 452 } 453 #endif 454 } 455 static jboolean onLoaded = JNI_FALSE; 456 if (onLoaded) { 457 // We may have to wait to fire OnLoad until TLS is initialized. 458 if (ThreadLocalStorage::is_initialized()) { 459 // The JNI_OnLoad handling is normally done by method load in 460 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 461 // explicitly so we have to check for JNI_OnLoad as well 462 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 463 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 464 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 465 if (JNI_OnLoad != NULL) { 466 JavaThread* thread = JavaThread::current(); 467 ThreadToNativeFromVM ttn(thread); 468 HandleMark hm(thread); 469 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 470 onLoaded = JNI_TRUE; 471 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 472 vm_exit_during_initialization("Unsupported JNI version"); 473 } 474 } 475 } 476 } 477 return _native_java_library; 478 } 479 480 /* 481 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 482 * If check_lib == true then we are looking for an 483 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 484 * this library is statically linked into the image. 485 * If check_lib == false then we will look for the appropriate symbol in the 486 * executable if agent_lib->is_static_lib() == true or in the shared library 487 * referenced by 'handle'. 488 */ 489 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 490 const char *syms[], size_t syms_len) { 491 assert(agent_lib != NULL, "sanity check"); 492 const char *lib_name; 493 void *handle = agent_lib->os_lib(); 494 void *entryName = NULL; 495 char *agent_function_name; 496 size_t i; 497 498 // If checking then use the agent name otherwise test is_static_lib() to 499 // see how to process this lookup 500 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 501 for (i = 0; i < syms_len; i++) { 502 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 503 if (agent_function_name == NULL) { 504 break; 505 } 506 entryName = dll_lookup(handle, agent_function_name); 507 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread); 508 if (entryName != NULL) { 509 break; 510 } 511 } 512 return entryName; 513 } 514 515 // See if the passed in agent is statically linked into the VM image. 516 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 517 size_t syms_len) { 518 void *ret; 519 void *proc_handle; 520 void *save_handle; 521 522 assert(agent_lib != NULL, "sanity check"); 523 if (agent_lib->name() == NULL) { 524 return false; 525 } 526 proc_handle = get_default_process_handle(); 527 // Check for Agent_OnLoad/Attach_lib_name function 528 save_handle = agent_lib->os_lib(); 529 // We want to look in this process' symbol table. 530 agent_lib->set_os_lib(proc_handle); 531 ret = find_agent_function(agent_lib, true, syms, syms_len); 532 if (ret != NULL) { 533 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 534 agent_lib->set_valid(); 535 agent_lib->set_static_lib(true); 536 return true; 537 } 538 agent_lib->set_os_lib(save_handle); 539 return false; 540 } 541 542 // --------------------- heap allocation utilities --------------------- 543 544 char *os::strdup(const char *str, MEMFLAGS flags) { 545 size_t size = strlen(str); 546 char *dup_str = (char *)malloc(size + 1, flags); 547 if (dup_str == NULL) return NULL; 548 strcpy(dup_str, str); 549 return dup_str; 550 } 551 552 553 554 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 555 556 #ifdef ASSERT 557 static void verify_memory(void* ptr) { 558 GuardedMemory guarded(ptr); 559 if (!guarded.verify_guards()) { 560 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 561 tty->print_cr("## memory stomp:"); 562 guarded.print_on(tty); 563 fatal("memory stomping error"); 564 } 565 } 566 #endif 567 568 // 569 // This function supports testing of the malloc out of memory 570 // condition without really running the system out of memory. 571 // 572 static u_char* testMalloc(size_t alloc_size) { 573 assert(MallocMaxTestWords > 0, "sanity check"); 574 575 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 576 return NULL; 577 } 578 579 u_char* ptr = (u_char*)::malloc(alloc_size); 580 581 if (ptr != NULL) { 582 Atomic::add(((jint) (alloc_size / BytesPerWord)), 583 (volatile jint *) &cur_malloc_words); 584 } 585 return ptr; 586 } 587 588 void* os::malloc(size_t size, MEMFLAGS flags) { 589 return os::malloc(size, flags, CALLER_PC); 590 } 591 592 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 593 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 594 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 595 596 #ifdef ASSERT 597 // checking for the WatcherThread and crash_protection first 598 // since os::malloc can be called when the libjvm.{dll,so} is 599 // first loaded and we don't have a thread yet. 600 // try to find the thread after we see that the watcher thread 601 // exists and has crash protection. 602 WatcherThread *wt = WatcherThread::watcher_thread(); 603 if (wt != NULL && wt->has_crash_protection()) { 604 Thread* thread = ThreadLocalStorage::get_thread_slow(); 605 if (thread == wt) { 606 assert(!wt->has_crash_protection(), 607 "Can't malloc with crash protection from WatcherThread"); 608 } 609 } 610 #endif 611 612 if (size == 0) { 613 // return a valid pointer if size is zero 614 // if NULL is returned the calling functions assume out of memory. 615 size = 1; 616 } 617 618 // NMT support 619 NMT_TrackingLevel level = MemTracker::tracking_level(); 620 size_t nmt_header_size = MemTracker::malloc_header_size(level); 621 622 #ifndef ASSERT 623 const size_t alloc_size = size + nmt_header_size; 624 #else 625 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size); 626 if (size + nmt_header_size > alloc_size) { // Check for rollover. 627 return NULL; 628 } 629 #endif 630 631 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 632 633 u_char* ptr; 634 if (MallocMaxTestWords > 0) { 635 ptr = testMalloc(alloc_size); 636 } else { 637 ptr = (u_char*)::malloc(alloc_size); 638 } 639 640 #ifdef ASSERT 641 if (ptr == NULL) { 642 return NULL; 643 } 644 // Wrap memory with guard 645 GuardedMemory guarded(ptr, size + nmt_header_size); 646 ptr = guarded.get_user_ptr(); 647 #endif 648 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 649 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 650 breakpoint(); 651 } 652 debug_only(if (paranoid) verify_memory(ptr)); 653 if (PrintMalloc && tty != NULL) { 654 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 655 } 656 657 // we do not track guard memory 658 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level); 659 } 660 661 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 662 return os::realloc(memblock, size, flags, CALLER_PC); 663 } 664 665 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 666 667 #ifndef ASSERT 668 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 669 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 670 // NMT support 671 void* membase = MemTracker::record_free(memblock); 672 NMT_TrackingLevel level = MemTracker::tracking_level(); 673 size_t nmt_header_size = MemTracker::malloc_header_size(level); 674 void* ptr = ::realloc(membase, size + nmt_header_size); 675 return MemTracker::record_malloc(ptr, size, memflags, stack, level); 676 #else 677 if (memblock == NULL) { 678 return os::malloc(size, memflags, stack); 679 } 680 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 681 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 682 breakpoint(); 683 } 684 // NMT support 685 void* membase = MemTracker::malloc_base(memblock); 686 verify_memory(membase); 687 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 688 if (size == 0) { 689 return NULL; 690 } 691 // always move the block 692 void* ptr = os::malloc(size, memflags, stack); 693 if (PrintMalloc) { 694 tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 695 } 696 // Copy to new memory if malloc didn't fail 697 if ( ptr != NULL ) { 698 GuardedMemory guarded(MemTracker::malloc_base(memblock)); 699 // Guard's user data contains NMT header 700 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock); 701 memcpy(ptr, memblock, MIN2(size, memblock_size)); 702 if (paranoid) verify_memory(MemTracker::malloc_base(ptr)); 703 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 704 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 705 breakpoint(); 706 } 707 os::free(memblock); 708 } 709 return ptr; 710 #endif 711 } 712 713 714 void os::free(void *memblock, MEMFLAGS memflags) { 715 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 716 #ifdef ASSERT 717 if (memblock == NULL) return; 718 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 719 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 720 breakpoint(); 721 } 722 void* membase = MemTracker::record_free(memblock); 723 verify_memory(membase); 724 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 725 726 GuardedMemory guarded(membase); 727 size_t size = guarded.get_user_size(); 728 inc_stat_counter(&free_bytes, size); 729 membase = guarded.release_for_freeing(); 730 if (PrintMalloc && tty != NULL) { 731 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase); 732 } 733 ::free(membase); 734 #else 735 void* membase = MemTracker::record_free(memblock); 736 ::free(membase); 737 #endif 738 } 739 740 void os::init_random(long initval) { 741 _rand_seed = initval; 742 } 743 744 745 long os::random() { 746 /* standard, well-known linear congruential random generator with 747 * next_rand = (16807*seed) mod (2**31-1) 748 * see 749 * (1) "Random Number Generators: Good Ones Are Hard to Find", 750 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 751 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 752 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 753 */ 754 const long a = 16807; 755 const unsigned long m = 2147483647; 756 const long q = m / a; assert(q == 127773, "weird math"); 757 const long r = m % a; assert(r == 2836, "weird math"); 758 759 // compute az=2^31p+q 760 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 761 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 762 lo += (hi & 0x7FFF) << 16; 763 764 // if q overflowed, ignore the overflow and increment q 765 if (lo > m) { 766 lo &= m; 767 ++lo; 768 } 769 lo += hi >> 15; 770 771 // if (p+q) overflowed, ignore the overflow and increment (p+q) 772 if (lo > m) { 773 lo &= m; 774 ++lo; 775 } 776 return (_rand_seed = lo); 777 } 778 779 // The INITIALIZED state is distinguished from the SUSPENDED state because the 780 // conditions in which a thread is first started are different from those in which 781 // a suspension is resumed. These differences make it hard for us to apply the 782 // tougher checks when starting threads that we want to do when resuming them. 783 // However, when start_thread is called as a result of Thread.start, on a Java 784 // thread, the operation is synchronized on the Java Thread object. So there 785 // cannot be a race to start the thread and hence for the thread to exit while 786 // we are working on it. Non-Java threads that start Java threads either have 787 // to do so in a context in which races are impossible, or should do appropriate 788 // locking. 789 790 void os::start_thread(Thread* thread) { 791 // guard suspend/resume 792 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 793 OSThread* osthread = thread->osthread(); 794 osthread->set_state(RUNNABLE); 795 pd_start_thread(thread); 796 } 797 798 //--------------------------------------------------------------------------- 799 // Helper functions for fatal error handler 800 801 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 802 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 803 804 int cols = 0; 805 int cols_per_line = 0; 806 switch (unitsize) { 807 case 1: cols_per_line = 16; break; 808 case 2: cols_per_line = 8; break; 809 case 4: cols_per_line = 4; break; 810 case 8: cols_per_line = 2; break; 811 default: return; 812 } 813 814 address p = start; 815 st->print(PTR_FORMAT ": ", start); 816 while (p < end) { 817 switch (unitsize) { 818 case 1: st->print("%02x", *(u1*)p); break; 819 case 2: st->print("%04x", *(u2*)p); break; 820 case 4: st->print("%08x", *(u4*)p); break; 821 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 822 } 823 p += unitsize; 824 cols++; 825 if (cols >= cols_per_line && p < end) { 826 cols = 0; 827 st->cr(); 828 st->print(PTR_FORMAT ": ", p); 829 } else { 830 st->print(" "); 831 } 832 } 833 st->cr(); 834 } 835 836 void os::print_environment_variables(outputStream* st, const char** env_list, 837 char* buffer, int len) { 838 if (env_list) { 839 st->print_cr("Environment Variables:"); 840 841 for (int i = 0; env_list[i] != NULL; i++) { 842 if (getenv(env_list[i], buffer, len)) { 843 st->print("%s", env_list[i]); 844 st->print("="); 845 st->print_cr("%s", buffer); 846 } 847 } 848 } 849 } 850 851 void os::print_cpu_info(outputStream* st) { 852 // cpu 853 st->print("CPU:"); 854 st->print("total %d", os::processor_count()); 855 // It's not safe to query number of active processors after crash 856 // st->print("(active %d)", os::active_processor_count()); but we can 857 // print the initial number of active processors. 858 // We access the raw value here because the assert in the accessor will 859 // fail if the crash occurs before initialization of this value. 860 st->print(" (initial active %d)", _initial_active_processor_count); 861 st->print(" %s", VM_Version::cpu_features()); 862 st->cr(); 863 pd_print_cpu_info(st); 864 } 865 866 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) { 867 const int secs_per_day = 86400; 868 const int secs_per_hour = 3600; 869 const int secs_per_min = 60; 870 871 time_t tloc; 872 (void)time(&tloc); 873 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 874 875 struct tm tz; 876 if (localtime_pd(&tloc, &tz) != NULL) { 877 ::strftime(buf, buflen, "%Z", &tz); 878 st->print_cr("timezone: %s", buf); 879 } 880 881 double t = os::elapsedTime(); 882 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 883 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 884 // before printf. We lost some precision, but who cares? 885 int eltime = (int)t; // elapsed time in seconds 886 887 // print elapsed time in a human-readable format: 888 int eldays = eltime / secs_per_day; 889 int day_secs = eldays * secs_per_day; 890 int elhours = (eltime - day_secs) / secs_per_hour; 891 int hour_secs = elhours * secs_per_hour; 892 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 893 int minute_secs = elmins * secs_per_min; 894 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 895 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 896 } 897 898 // moved from debug.cpp (used to be find()) but still called from there 899 // The verbose parameter is only set by the debug code in one case 900 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 901 address addr = (address)x; 902 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 903 if (b != NULL) { 904 if (b->is_buffer_blob()) { 905 // the interpreter is generated into a buffer blob 906 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 907 if (i != NULL) { 908 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 909 i->print_on(st); 910 return; 911 } 912 if (Interpreter::contains(addr)) { 913 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 914 " (not bytecode specific)", addr); 915 return; 916 } 917 // 918 if (AdapterHandlerLibrary::contains(b)) { 919 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 920 AdapterHandlerLibrary::print_handler_on(st, b); 921 } 922 // the stubroutines are generated into a buffer blob 923 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 924 if (d != NULL) { 925 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 926 d->print_on(st); 927 st->cr(); 928 return; 929 } 930 if (StubRoutines::contains(addr)) { 931 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 932 "stub routine", addr); 933 return; 934 } 935 // the InlineCacheBuffer is using stubs generated into a buffer blob 936 if (InlineCacheBuffer::contains(addr)) { 937 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 938 return; 939 } 940 VtableStub* v = VtableStubs::stub_containing(addr); 941 if (v != NULL) { 942 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 943 v->print_on(st); 944 st->cr(); 945 return; 946 } 947 } 948 nmethod* nm = b->as_nmethod_or_null(); 949 if (nm != NULL) { 950 ResourceMark rm; 951 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 952 addr, (int)(addr - nm->entry_point()), nm); 953 if (verbose) { 954 st->print(" for "); 955 nm->method()->print_value_on(st); 956 } 957 st->cr(); 958 nm->print_nmethod(verbose); 959 return; 960 } 961 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 962 b->print_on(st); 963 return; 964 } 965 966 if (Universe::heap()->is_in(addr)) { 967 HeapWord* p = Universe::heap()->block_start(addr); 968 bool print = false; 969 // If we couldn't find it it just may mean that heap wasn't parseable 970 // See if we were just given an oop directly 971 if (p != NULL && Universe::heap()->block_is_obj(p)) { 972 print = true; 973 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 974 p = (HeapWord*) addr; 975 print = true; 976 } 977 if (print) { 978 if (p == (HeapWord*) addr) { 979 st->print_cr(INTPTR_FORMAT " is an oop", addr); 980 } else { 981 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 982 } 983 oop(p)->print_on(st); 984 return; 985 } 986 } else { 987 if (Universe::heap()->is_in_reserved(addr)) { 988 st->print_cr(INTPTR_FORMAT " is an unallocated location " 989 "in the heap", addr); 990 return; 991 } 992 } 993 if (JNIHandles::is_global_handle((jobject) addr)) { 994 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 995 return; 996 } 997 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 998 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 999 return; 1000 } 1001 #ifndef PRODUCT 1002 // we don't keep the block list in product mode 1003 if (JNIHandleBlock::any_contains((jobject) addr)) { 1004 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 1005 return; 1006 } 1007 #endif 1008 1009 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1010 // Check for privilege stack 1011 if (thread->privileged_stack_top() != NULL && 1012 thread->privileged_stack_top()->contains(addr)) { 1013 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1014 "for thread: " INTPTR_FORMAT, addr, thread); 1015 if (verbose) thread->print_on(st); 1016 return; 1017 } 1018 // If the addr is a java thread print information about that. 1019 if (addr == (address)thread) { 1020 if (verbose) { 1021 thread->print_on(st); 1022 } else { 1023 st->print_cr(INTPTR_FORMAT " is a thread", addr); 1024 } 1025 return; 1026 } 1027 // If the addr is in the stack region for this thread then report that 1028 // and print thread info 1029 if (thread->stack_base() >= addr && 1030 addr > (thread->stack_base() - thread->stack_size())) { 1031 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1032 INTPTR_FORMAT, addr, thread); 1033 if (verbose) thread->print_on(st); 1034 return; 1035 } 1036 1037 } 1038 1039 // Check if in metaspace and print types that have vptrs (only method now) 1040 if (Metaspace::contains(addr)) { 1041 if (Method::has_method_vptr((const void*)addr)) { 1042 ((Method*)addr)->print_value_on(st); 1043 st->cr(); 1044 } else { 1045 // Use addr->print() from the debugger instead (not here) 1046 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr); 1047 } 1048 return; 1049 } 1050 1051 // Try an OS specific find 1052 if (os::find(addr, st)) { 1053 return; 1054 } 1055 1056 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1057 } 1058 1059 // Looks like all platforms except IA64 can use the same function to check 1060 // if C stack is walkable beyond current frame. The check for fp() is not 1061 // necessary on Sparc, but it's harmless. 1062 bool os::is_first_C_frame(frame* fr) { 1063 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32) 1064 // On IA64 we have to check if the callers bsp is still valid 1065 // (i.e. within the register stack bounds). 1066 // Notice: this only works for threads created by the VM and only if 1067 // we walk the current stack!!! If we want to be able to walk 1068 // arbitrary other threads, we'll have to somehow store the thread 1069 // object in the frame. 1070 Thread *thread = Thread::current(); 1071 if ((address)fr->fp() <= 1072 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1073 // This check is a little hacky, because on Linux the first C 1074 // frame's ('start_thread') register stack frame starts at 1075 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1076 // ('__pthread_bound_body') register stack frame seems to really 1077 // start at "register_stack_base". 1078 return true; 1079 } else { 1080 return false; 1081 } 1082 #elif defined(IA64) && defined(_WIN32) 1083 return true; 1084 #else 1085 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1086 // Check usp first, because if that's bad the other accessors may fault 1087 // on some architectures. Ditto ufp second, etc. 1088 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1089 // sp on amd can be 32 bit aligned. 1090 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1091 1092 uintptr_t usp = (uintptr_t)fr->sp(); 1093 if ((usp & sp_align_mask) != 0) return true; 1094 1095 uintptr_t ufp = (uintptr_t)fr->fp(); 1096 if ((ufp & fp_align_mask) != 0) return true; 1097 1098 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1099 if ((old_sp & sp_align_mask) != 0) return true; 1100 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1101 1102 uintptr_t old_fp = (uintptr_t)fr->link(); 1103 if ((old_fp & fp_align_mask) != 0) return true; 1104 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1105 1106 // stack grows downwards; if old_fp is below current fp or if the stack 1107 // frame is too large, either the stack is corrupted or fp is not saved 1108 // on stack (i.e. on x86, ebp may be used as general register). The stack 1109 // is not walkable beyond current frame. 1110 if (old_fp < ufp) return true; 1111 if (old_fp - ufp > 64 * K) return true; 1112 1113 return false; 1114 #endif 1115 } 1116 1117 #ifdef ASSERT 1118 extern "C" void test_random() { 1119 const double m = 2147483647; 1120 double mean = 0.0, variance = 0.0, t; 1121 long reps = 10000; 1122 unsigned long seed = 1; 1123 1124 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1125 os::init_random(seed); 1126 long num; 1127 for (int k = 0; k < reps; k++) { 1128 num = os::random(); 1129 double u = (double)num / m; 1130 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1131 1132 // calculate mean and variance of the random sequence 1133 mean += u; 1134 variance += (u*u); 1135 } 1136 mean /= reps; 1137 variance /= (reps - 1); 1138 1139 assert(num == 1043618065, "bad seed"); 1140 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1141 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1142 const double eps = 0.0001; 1143 t = fabsd(mean - 0.5018); 1144 assert(t < eps, "bad mean"); 1145 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1146 assert(t < eps, "bad variance"); 1147 } 1148 #endif 1149 1150 1151 // Set up the boot classpath. 1152 1153 char* os::format_boot_path(const char* format_string, 1154 const char* home, 1155 int home_len, 1156 char fileSep, 1157 char pathSep) { 1158 assert((fileSep == '/' && pathSep == ':') || 1159 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1160 1161 // Scan the format string to determine the length of the actual 1162 // boot classpath, and handle platform dependencies as well. 1163 int formatted_path_len = 0; 1164 const char* p; 1165 for (p = format_string; *p != 0; ++p) { 1166 if (*p == '%') formatted_path_len += home_len - 1; 1167 ++formatted_path_len; 1168 } 1169 1170 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1171 if (formatted_path == NULL) { 1172 return NULL; 1173 } 1174 1175 // Create boot classpath from format, substituting separator chars and 1176 // java home directory. 1177 char* q = formatted_path; 1178 for (p = format_string; *p != 0; ++p) { 1179 switch (*p) { 1180 case '%': 1181 strcpy(q, home); 1182 q += home_len; 1183 break; 1184 case '/': 1185 *q++ = fileSep; 1186 break; 1187 case ':': 1188 *q++ = pathSep; 1189 break; 1190 default: 1191 *q++ = *p; 1192 } 1193 } 1194 *q = '\0'; 1195 1196 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1197 return formatted_path; 1198 } 1199 1200 1201 bool os::set_boot_path(char fileSep, char pathSep) { 1202 const char* home = Arguments::get_java_home(); 1203 int home_len = (int)strlen(home); 1204 1205 static const char* meta_index_dir_format = "%/lib/"; 1206 static const char* meta_index_format = "%/lib/meta-index"; 1207 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1208 if (meta_index == NULL) return false; 1209 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1210 if (meta_index_dir == NULL) return false; 1211 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1212 1213 // Any modification to the JAR-file list, for the boot classpath must be 1214 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1215 // path class JARs, are stripped for StackMapTable to reduce download size. 1216 static const char classpath_format[] = 1217 "%/lib/resources.jar:" 1218 "%/lib/rt.jar:" 1219 "%/lib/sunrsasign.jar:" 1220 "%/lib/jsse.jar:" 1221 "%/lib/jce.jar:" 1222 "%/lib/charsets.jar:" 1223 "%/lib/jfr.jar:" 1224 "%/classes"; 1225 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1226 if (sysclasspath == NULL) return false; 1227 Arguments::set_sysclasspath(sysclasspath); 1228 1229 return true; 1230 } 1231 1232 /* 1233 * Splits a path, based on its separator, the number of 1234 * elements is returned back in n. 1235 * It is the callers responsibility to: 1236 * a> check the value of n, and n may be 0. 1237 * b> ignore any empty path elements 1238 * c> free up the data. 1239 */ 1240 char** os::split_path(const char* path, int* n) { 1241 *n = 0; 1242 if (path == NULL || strlen(path) == 0) { 1243 return NULL; 1244 } 1245 const char psepchar = *os::path_separator(); 1246 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1247 if (inpath == NULL) { 1248 return NULL; 1249 } 1250 strcpy(inpath, path); 1251 int count = 1; 1252 char* p = strchr(inpath, psepchar); 1253 // Get a count of elements to allocate memory 1254 while (p != NULL) { 1255 count++; 1256 p++; 1257 p = strchr(p, psepchar); 1258 } 1259 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1260 if (opath == NULL) { 1261 return NULL; 1262 } 1263 1264 // do the actual splitting 1265 p = inpath; 1266 for (int i = 0 ; i < count ; i++) { 1267 size_t len = strcspn(p, os::path_separator()); 1268 if (len > JVM_MAXPATHLEN) { 1269 return NULL; 1270 } 1271 // allocate the string and add terminator storage 1272 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1273 if (s == NULL) { 1274 return NULL; 1275 } 1276 strncpy(s, p, len); 1277 s[len] = '\0'; 1278 opath[i] = s; 1279 p += len + 1; 1280 } 1281 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1282 *n = count; 1283 return opath; 1284 } 1285 1286 void os::set_memory_serialize_page(address page) { 1287 int count = log2_intptr(sizeof(class JavaThread)) - log2_int(64); 1288 _mem_serialize_page = (volatile int32_t *)page; 1289 // We initialize the serialization page shift count here 1290 // We assume a cache line size of 64 bytes 1291 assert(SerializePageShiftCount == count, 1292 "thread size changed, fix SerializePageShiftCount constant"); 1293 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1294 } 1295 1296 static volatile intptr_t SerializePageLock = 0; 1297 1298 // This method is called from signal handler when SIGSEGV occurs while the current 1299 // thread tries to store to the "read-only" memory serialize page during state 1300 // transition. 1301 void os::block_on_serialize_page_trap() { 1302 if (TraceSafepoint) { 1303 tty->print_cr("Block until the serialize page permission restored"); 1304 } 1305 // When VMThread is holding the SerializePageLock during modifying the 1306 // access permission of the memory serialize page, the following call 1307 // will block until the permission of that page is restored to rw. 1308 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1309 // this case, it's OK as the signal is synchronous and we know precisely when 1310 // it can occur. 1311 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1312 Thread::muxRelease(&SerializePageLock); 1313 } 1314 1315 // Serialize all thread state variables 1316 void os::serialize_thread_states() { 1317 // On some platforms such as Solaris & Linux, the time duration of the page 1318 // permission restoration is observed to be much longer than expected due to 1319 // scheduler starvation problem etc. To avoid the long synchronization 1320 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1321 // the mutator thread if such case is encountered. See bug 6546278 for details. 1322 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1323 os::protect_memory((char *)os::get_memory_serialize_page(), 1324 os::vm_page_size(), MEM_PROT_READ); 1325 os::protect_memory((char *)os::get_memory_serialize_page(), 1326 os::vm_page_size(), MEM_PROT_RW); 1327 Thread::muxRelease(&SerializePageLock); 1328 } 1329 1330 // Returns true if the current stack pointer is above the stack shadow 1331 // pages, false otherwise. 1332 1333 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1334 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1335 address sp = current_stack_pointer(); 1336 // Check if we have StackShadowPages above the yellow zone. This parameter 1337 // is dependent on the depth of the maximum VM call stack possible from 1338 // the handler for stack overflow. 'instanceof' in the stack overflow 1339 // handler or a println uses at least 8k stack of VM and native code 1340 // respectively. 1341 const int framesize_in_bytes = 1342 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1343 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1344 * vm_page_size()) + framesize_in_bytes; 1345 // The very lower end of the stack 1346 address stack_limit = thread->stack_base() - thread->stack_size(); 1347 return (sp > (stack_limit + reserved_area)); 1348 } 1349 1350 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1351 assert(min_pages > 0, "sanity"); 1352 if (UseLargePages) { 1353 const size_t max_page_size = region_size / min_pages; 1354 1355 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1356 const size_t page_size = _page_sizes[i]; 1357 if (page_size <= max_page_size) { 1358 if (!must_be_aligned || is_size_aligned(region_size, page_size)) { 1359 return page_size; 1360 } 1361 } 1362 } 1363 } 1364 1365 return vm_page_size(); 1366 } 1367 1368 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1369 return page_size_for_region(region_size, min_pages, true); 1370 } 1371 1372 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1373 return page_size_for_region(region_size, min_pages, false); 1374 } 1375 1376 #ifndef PRODUCT 1377 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1378 { 1379 if (TracePageSizes) { 1380 tty->print("%s: ", str); 1381 for (int i = 0; i < count; ++i) { 1382 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1383 } 1384 tty->cr(); 1385 } 1386 } 1387 1388 void os::trace_page_sizes(const char* str, const size_t region_min_size, 1389 const size_t region_max_size, const size_t page_size, 1390 const char* base, const size_t size) 1391 { 1392 if (TracePageSizes) { 1393 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1394 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1395 " size=" SIZE_FORMAT, 1396 str, region_min_size, region_max_size, 1397 page_size, base, size); 1398 } 1399 } 1400 #endif // #ifndef PRODUCT 1401 1402 // This is the working definition of a server class machine: 1403 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1404 // because the graphics memory (?) sometimes masks physical memory. 1405 // If you want to change the definition of a server class machine 1406 // on some OS or platform, e.g., >=4GB on Windohs platforms, 1407 // then you'll have to parameterize this method based on that state, 1408 // as was done for logical processors here, or replicate and 1409 // specialize this method for each platform. (Or fix os to have 1410 // some inheritance structure and use subclassing. Sigh.) 1411 // If you want some platform to always or never behave as a server 1412 // class machine, change the setting of AlwaysActAsServerClassMachine 1413 // and NeverActAsServerClassMachine in globals*.hpp. 1414 bool os::is_server_class_machine() { 1415 // First check for the early returns 1416 if (NeverActAsServerClassMachine) { 1417 return false; 1418 } 1419 if (AlwaysActAsServerClassMachine) { 1420 return true; 1421 } 1422 // Then actually look at the machine 1423 bool result = false; 1424 const unsigned int server_processors = 2; 1425 const julong server_memory = 2UL * G; 1426 // We seem not to get our full complement of memory. 1427 // We allow some part (1/8?) of the memory to be "missing", 1428 // based on the sizes of DIMMs, and maybe graphics cards. 1429 const julong missing_memory = 256UL * M; 1430 1431 /* Is this a server class machine? */ 1432 if ((os::active_processor_count() >= (int)server_processors) && 1433 (os::physical_memory() >= (server_memory - missing_memory))) { 1434 const unsigned int logical_processors = 1435 VM_Version::logical_processors_per_package(); 1436 if (logical_processors > 1) { 1437 const unsigned int physical_packages = 1438 os::active_processor_count() / logical_processors; 1439 if (physical_packages > server_processors) { 1440 result = true; 1441 } 1442 } else { 1443 result = true; 1444 } 1445 } 1446 return result; 1447 } 1448 1449 void os::initialize_initial_active_processor_count() { 1450 assert(_initial_active_processor_count == 0, "Initial active processor count already set."); 1451 _initial_active_processor_count = active_processor_count(); 1452 } 1453 1454 void os::SuspendedThreadTask::run() { 1455 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1456 internal_do_task(); 1457 _done = true; 1458 } 1459 1460 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1461 return os::pd_create_stack_guard_pages(addr, bytes); 1462 } 1463 1464 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1465 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1466 if (result != NULL) { 1467 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1468 } 1469 1470 return result; 1471 } 1472 1473 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1474 MEMFLAGS flags) { 1475 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1476 if (result != NULL) { 1477 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1478 MemTracker::record_virtual_memory_type((address)result, flags); 1479 } 1480 1481 return result; 1482 } 1483 1484 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1485 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1486 if (result != NULL) { 1487 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1488 } 1489 return result; 1490 } 1491 1492 void os::split_reserved_memory(char *base, size_t size, 1493 size_t split, bool realloc) { 1494 pd_split_reserved_memory(base, size, split, realloc); 1495 } 1496 1497 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1498 bool res = pd_commit_memory(addr, bytes, executable); 1499 if (res) { 1500 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1501 } 1502 return res; 1503 } 1504 1505 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1506 bool executable) { 1507 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1508 if (res) { 1509 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1510 } 1511 return res; 1512 } 1513 1514 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1515 const char* mesg) { 1516 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1517 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1518 } 1519 1520 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1521 bool executable, const char* mesg) { 1522 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1523 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1524 } 1525 1526 bool os::uncommit_memory(char* addr, size_t bytes) { 1527 bool res; 1528 if (MemTracker::tracking_level() > NMT_minimal) { 1529 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1530 res = pd_uncommit_memory(addr, bytes); 1531 if (res) { 1532 tkr.record((address)addr, bytes); 1533 } 1534 } else { 1535 res = pd_uncommit_memory(addr, bytes); 1536 } 1537 return res; 1538 } 1539 1540 bool os::release_memory(char* addr, size_t bytes) { 1541 bool res; 1542 if (MemTracker::tracking_level() > NMT_minimal) { 1543 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1544 res = pd_release_memory(addr, bytes); 1545 if (res) { 1546 tkr.record((address)addr, bytes); 1547 } 1548 } else { 1549 res = pd_release_memory(addr, bytes); 1550 } 1551 return res; 1552 } 1553 1554 void os::pretouch_memory(char* start, char* end) { 1555 for (volatile char *p = start; p < end; p += os::vm_page_size()) { 1556 *p = 0; 1557 } 1558 } 1559 1560 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1561 char *addr, size_t bytes, bool read_only, 1562 bool allow_exec) { 1563 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1564 if (result != NULL) { 1565 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1566 } 1567 return result; 1568 } 1569 1570 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1571 char *addr, size_t bytes, bool read_only, 1572 bool allow_exec) { 1573 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1574 read_only, allow_exec); 1575 } 1576 1577 bool os::unmap_memory(char *addr, size_t bytes) { 1578 bool result; 1579 if (MemTracker::tracking_level() > NMT_minimal) { 1580 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1581 result = pd_unmap_memory(addr, bytes); 1582 if (result) { 1583 tkr.record((address)addr, bytes); 1584 } 1585 } else { 1586 result = pd_unmap_memory(addr, bytes); 1587 } 1588 return result; 1589 } 1590 1591 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1592 pd_free_memory(addr, bytes, alignment_hint); 1593 } 1594 1595 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1596 pd_realign_memory(addr, bytes, alignment_hint); 1597 } 1598 1599 #ifndef TARGET_OS_FAMILY_windows 1600 /* try to switch state from state "from" to state "to" 1601 * returns the state set after the method is complete 1602 */ 1603 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1604 os::SuspendResume::State to) 1605 { 1606 os::SuspendResume::State result = 1607 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1608 if (result == from) { 1609 // success 1610 return to; 1611 } 1612 return result; 1613 } 1614 #endif 1615 1616 /////////////// Unit tests /////////////// 1617 1618 #ifndef PRODUCT 1619 1620 #define assert_eq(a,b) assert(a == b, err_msg(SIZE_FORMAT " != " SIZE_FORMAT, a, b)) 1621 1622 class TestOS : AllStatic { 1623 static size_t small_page_size() { 1624 return os::vm_page_size(); 1625 } 1626 1627 static size_t large_page_size() { 1628 const size_t large_page_size_example = 4 * M; 1629 return os::page_size_for_region_aligned(large_page_size_example, 1); 1630 } 1631 1632 static void test_page_size_for_region_aligned() { 1633 if (UseLargePages) { 1634 const size_t small_page = small_page_size(); 1635 const size_t large_page = large_page_size(); 1636 1637 if (large_page > small_page) { 1638 size_t num_small_pages_in_large = large_page / small_page; 1639 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large); 1640 1641 assert_eq(page, small_page); 1642 } 1643 } 1644 } 1645 1646 static void test_page_size_for_region_alignment() { 1647 if (UseLargePages) { 1648 const size_t small_page = small_page_size(); 1649 const size_t large_page = large_page_size(); 1650 if (large_page > small_page) { 1651 const size_t unaligned_region = large_page + 17; 1652 size_t page = os::page_size_for_region_aligned(unaligned_region, 1); 1653 assert_eq(page, small_page); 1654 1655 const size_t num_pages = 5; 1656 const size_t aligned_region = large_page * num_pages; 1657 page = os::page_size_for_region_aligned(aligned_region, num_pages); 1658 assert_eq(page, large_page); 1659 } 1660 } 1661 } 1662 1663 static void test_page_size_for_region_unaligned() { 1664 if (UseLargePages) { 1665 // Given exact page size, should return that page size. 1666 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1667 size_t expected = os::_page_sizes[i]; 1668 size_t actual = os::page_size_for_region_unaligned(expected, 1); 1669 assert_eq(expected, actual); 1670 } 1671 1672 // Given slightly larger size than a page size, return the page size. 1673 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1674 size_t expected = os::_page_sizes[i]; 1675 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1); 1676 assert_eq(expected, actual); 1677 } 1678 1679 // Given a slightly smaller size than a page size, 1680 // return the next smaller page size. 1681 if (os::_page_sizes[1] > os::_page_sizes[0]) { 1682 size_t expected = os::_page_sizes[0]; 1683 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1); 1684 assert_eq(actual, expected); 1685 } 1686 1687 // Return small page size for values less than a small page. 1688 size_t small_page = small_page_size(); 1689 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1); 1690 assert_eq(small_page, actual); 1691 } 1692 } 1693 1694 public: 1695 static void run_tests() { 1696 test_page_size_for_region_aligned(); 1697 test_page_size_for_region_alignment(); 1698 test_page_size_for_region_unaligned(); 1699 } 1700 }; 1701 1702 void TestOS_test() { 1703 TestOS::run_tests(); 1704 } 1705 1706 #endif // PRODUCT