os.cpp revision 6760:22b98ab2a69f
1/* 2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 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/codeCache.hpp" 31#include "code/icBuffer.hpp" 32#include "code/vtableStubs.hpp" 33#include "gc_implementation/shared/vmGCOperations.hpp" 34#include "interpreter/interpreter.hpp" 35#include "memory/allocation.inline.hpp" 36#ifdef ASSERT 37#include "memory/guardedMemory.hpp" 38#endif 39#include "oops/oop.inline.hpp" 40#include "prims/jvm.h" 41#include "prims/jvm_misc.hpp" 42#include "prims/privilegedStack.hpp" 43#include "runtime/arguments.hpp" 44#include "runtime/atomic.inline.hpp" 45#include "runtime/frame.inline.hpp" 46#include "runtime/interfaceSupport.hpp" 47#include "runtime/java.hpp" 48#include "runtime/javaCalls.hpp" 49#include "runtime/mutexLocker.hpp" 50#include "runtime/os.inline.hpp" 51#include "runtime/stubRoutines.hpp" 52#include "runtime/thread.inline.hpp" 53#include "runtime/vm_version.hpp" 54#include "services/attachListener.hpp" 55#include "services/memTracker.hpp" 56#include "services/threadService.hpp" 57#include "utilities/defaultStream.hpp" 58#include "utilities/events.hpp" 59 60# include <signal.h> 61 62PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 63 64OSThread* os::_starting_thread = NULL; 65address os::_polling_page = NULL; 66volatile int32_t* os::_mem_serialize_page = NULL; 67uintptr_t os::_serialize_page_mask = 0; 68long os::_rand_seed = 1; 69int os::_processor_count = 0; 70size_t os::_page_sizes[os::page_sizes_max]; 71 72#ifndef PRODUCT 73julong os::num_mallocs = 0; // # of calls to malloc/realloc 74julong os::alloc_bytes = 0; // # of bytes allocated 75julong os::num_frees = 0; // # of calls to free 76julong os::free_bytes = 0; // # of bytes freed 77#endif 78 79static juint cur_malloc_words = 0; // current size for MallocMaxTestWords 80 81void os_init_globals() { 82 // Called from init_globals(). 83 // See Threads::create_vm() in thread.cpp, and init.cpp. 84 os::init_globals(); 85} 86 87// Fill in buffer with current local time as an ISO-8601 string. 88// E.g., yyyy-mm-ddThh:mm:ss-zzzz. 89// Returns buffer, or NULL if it failed. 90// This would mostly be a call to 91// strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 92// except that on Windows the %z behaves badly, so we do it ourselves. 93// Also, people wanted milliseconds on there, 94// and strftime doesn't do milliseconds. 95char* os::iso8601_time(char* buffer, size_t buffer_length) { 96 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 97 // 1 2 98 // 12345678901234567890123456789 99 static const char* iso8601_format = 100 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; 101 static const size_t needed_buffer = 29; 102 103 // Sanity check the arguments 104 if (buffer == NULL) { 105 assert(false, "NULL buffer"); 106 return NULL; 107 } 108 if (buffer_length < needed_buffer) { 109 assert(false, "buffer_length too small"); 110 return NULL; 111 } 112 // Get the current time 113 jlong milliseconds_since_19700101 = javaTimeMillis(); 114 const int milliseconds_per_microsecond = 1000; 115 const time_t seconds_since_19700101 = 116 milliseconds_since_19700101 / milliseconds_per_microsecond; 117 const int milliseconds_after_second = 118 milliseconds_since_19700101 % milliseconds_per_microsecond; 119 // Convert the time value to a tm and timezone variable 120 struct tm time_struct; 121 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 122 assert(false, "Failed localtime_pd"); 123 return NULL; 124 } 125#if defined(_ALLBSD_SOURCE) 126 const time_t zone = (time_t) time_struct.tm_gmtoff; 127#else 128 const time_t zone = timezone; 129#endif 130 131 // If daylight savings time is in effect, 132 // we are 1 hour East of our time zone 133 const time_t seconds_per_minute = 60; 134 const time_t minutes_per_hour = 60; 135 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 136 time_t UTC_to_local = zone; 137 if (time_struct.tm_isdst > 0) { 138 UTC_to_local = UTC_to_local - seconds_per_hour; 139 } 140 // Compute the time zone offset. 141 // localtime_pd() sets timezone to the difference (in seconds) 142 // between UTC and and local time. 143 // ISO 8601 says we need the difference between local time and UTC, 144 // we change the sign of the localtime_pd() result. 145 const time_t local_to_UTC = -(UTC_to_local); 146 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 147 char sign_local_to_UTC = '+'; 148 time_t abs_local_to_UTC = local_to_UTC; 149 if (local_to_UTC < 0) { 150 sign_local_to_UTC = '-'; 151 abs_local_to_UTC = -(abs_local_to_UTC); 152 } 153 // Convert time zone offset seconds to hours and minutes. 154 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 155 const time_t zone_min = 156 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 157 158 // Print an ISO 8601 date and time stamp into the buffer 159 const int year = 1900 + time_struct.tm_year; 160 const int month = 1 + time_struct.tm_mon; 161 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, 162 year, 163 month, 164 time_struct.tm_mday, 165 time_struct.tm_hour, 166 time_struct.tm_min, 167 time_struct.tm_sec, 168 milliseconds_after_second, 169 sign_local_to_UTC, 170 zone_hours, 171 zone_min); 172 if (printed == 0) { 173 assert(false, "Failed jio_printf"); 174 return NULL; 175 } 176 return buffer; 177} 178 179OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 180#ifdef ASSERT 181 if (!(!thread->is_Java_thread() || 182 Thread::current() == thread || 183 Threads_lock->owned_by_self() 184 || thread->is_Compiler_thread() 185 )) { 186 assert(false, "possibility of dangling Thread pointer"); 187 } 188#endif 189 190 if (p >= MinPriority && p <= MaxPriority) { 191 int priority = java_to_os_priority[p]; 192 return set_native_priority(thread, priority); 193 } else { 194 assert(false, "Should not happen"); 195 return OS_ERR; 196 } 197} 198 199// The mapping from OS priority back to Java priority may be inexact because 200// Java priorities can map M:1 with native priorities. If you want the definite 201// Java priority then use JavaThread::java_priority() 202OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 203 int p; 204 int os_prio; 205 OSReturn ret = get_native_priority(thread, &os_prio); 206 if (ret != OS_OK) return ret; 207 208 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 209 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 210 } else { 211 // niceness values are in reverse order 212 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 213 } 214 priority = (ThreadPriority)p; 215 return OS_OK; 216} 217 218 219// --------------------- sun.misc.Signal (optional) --------------------- 220 221 222// SIGBREAK is sent by the keyboard to query the VM state 223#ifndef SIGBREAK 224#define SIGBREAK SIGQUIT 225#endif 226 227// sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 228 229 230static void signal_thread_entry(JavaThread* thread, TRAPS) { 231 os::set_priority(thread, NearMaxPriority); 232 while (true) { 233 int sig; 234 { 235 // FIXME : Currently we have not decided what should be the status 236 // for this java thread blocked here. Once we decide about 237 // that we should fix this. 238 sig = os::signal_wait(); 239 } 240 if (sig == os::sigexitnum_pd()) { 241 // Terminate the signal thread 242 return; 243 } 244 245 switch (sig) { 246 case SIGBREAK: { 247 // Check if the signal is a trigger to start the Attach Listener - in that 248 // case don't print stack traces. 249 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 250 continue; 251 } 252 // Print stack traces 253 // Any SIGBREAK operations added here should make sure to flush 254 // the output stream (e.g. tty->flush()) after output. See 4803766. 255 // Each module also prints an extra carriage return after its output. 256 VM_PrintThreads op; 257 VMThread::execute(&op); 258 VM_PrintJNI jni_op; 259 VMThread::execute(&jni_op); 260 VM_FindDeadlocks op1(tty); 261 VMThread::execute(&op1); 262 Universe::print_heap_at_SIGBREAK(); 263 if (PrintClassHistogram) { 264 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */); 265 VMThread::execute(&op1); 266 } 267 if (JvmtiExport::should_post_data_dump()) { 268 JvmtiExport::post_data_dump(); 269 } 270 break; 271 } 272 default: { 273 // Dispatch the signal to java 274 HandleMark hm(THREAD); 275 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 276 KlassHandle klass (THREAD, k); 277 if (klass.not_null()) { 278 JavaValue result(T_VOID); 279 JavaCallArguments args; 280 args.push_int(sig); 281 JavaCalls::call_static( 282 &result, 283 klass, 284 vmSymbols::dispatch_name(), 285 vmSymbols::int_void_signature(), 286 &args, 287 THREAD 288 ); 289 } 290 if (HAS_PENDING_EXCEPTION) { 291 // tty is initialized early so we don't expect it to be null, but 292 // if it is we can't risk doing an initialization that might 293 // trigger additional out-of-memory conditions 294 if (tty != NULL) { 295 char klass_name[256]; 296 char tmp_sig_name[16]; 297 const char* sig_name = "UNKNOWN"; 298 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 299 name()->as_klass_external_name(klass_name, 256); 300 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 301 sig_name = tmp_sig_name; 302 warning("Exception %s occurred dispatching signal %s to handler" 303 "- the VM may need to be forcibly terminated", 304 klass_name, sig_name ); 305 } 306 CLEAR_PENDING_EXCEPTION; 307 } 308 } 309 } 310 } 311} 312 313void os::init_before_ergo() { 314 // We need to initialize large page support here because ergonomics takes some 315 // decisions depending on large page support and the calculated large page size. 316 large_page_init(); 317} 318 319void os::signal_init() { 320 if (!ReduceSignalUsage) { 321 // Setup JavaThread for processing signals 322 EXCEPTION_MARK; 323 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 324 instanceKlassHandle klass (THREAD, k); 325 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 326 327 const char thread_name[] = "Signal Dispatcher"; 328 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 329 330 // Initialize thread_oop to put it into the system threadGroup 331 Handle thread_group (THREAD, Universe::system_thread_group()); 332 JavaValue result(T_VOID); 333 JavaCalls::call_special(&result, thread_oop, 334 klass, 335 vmSymbols::object_initializer_name(), 336 vmSymbols::threadgroup_string_void_signature(), 337 thread_group, 338 string, 339 CHECK); 340 341 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 342 JavaCalls::call_special(&result, 343 thread_group, 344 group, 345 vmSymbols::add_method_name(), 346 vmSymbols::thread_void_signature(), 347 thread_oop, // ARG 1 348 CHECK); 349 350 os::signal_init_pd(); 351 352 { MutexLocker mu(Threads_lock); 353 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 354 355 // At this point it may be possible that no osthread was created for the 356 // JavaThread due to lack of memory. We would have to throw an exception 357 // in that case. However, since this must work and we do not allow 358 // exceptions anyway, check and abort if this fails. 359 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 360 vm_exit_during_initialization("java.lang.OutOfMemoryError", 361 os::native_thread_creation_failed_msg()); 362 } 363 364 java_lang_Thread::set_thread(thread_oop(), signal_thread); 365 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 366 java_lang_Thread::set_daemon(thread_oop()); 367 368 signal_thread->set_threadObj(thread_oop()); 369 Threads::add(signal_thread); 370 Thread::start(signal_thread); 371 } 372 // Handle ^BREAK 373 os::signal(SIGBREAK, os::user_handler()); 374 } 375} 376 377 378void os::terminate_signal_thread() { 379 if (!ReduceSignalUsage) 380 signal_notify(sigexitnum_pd()); 381} 382 383 384// --------------------- loading libraries --------------------- 385 386typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 387extern struct JavaVM_ main_vm; 388 389static void* _native_java_library = NULL; 390 391void* os::native_java_library() { 392 if (_native_java_library == NULL) { 393 char buffer[JVM_MAXPATHLEN]; 394 char ebuf[1024]; 395 396 // Try to load verify dll first. In 1.3 java dll depends on it and is not 397 // always able to find it when the loading executable is outside the JDK. 398 // In order to keep working with 1.2 we ignore any loading errors. 399 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 400 "verify")) { 401 dll_load(buffer, ebuf, sizeof(ebuf)); 402 } 403 404 // Load java dll 405 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 406 "java")) { 407 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 408 } 409 if (_native_java_library == NULL) { 410 vm_exit_during_initialization("Unable to load native library", ebuf); 411 } 412 413#if defined(__OpenBSD__) 414 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 415 // ignore errors 416 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 417 "net")) { 418 dll_load(buffer, ebuf, sizeof(ebuf)); 419 } 420#endif 421 } 422 static jboolean onLoaded = JNI_FALSE; 423 if (onLoaded) { 424 // We may have to wait to fire OnLoad until TLS is initialized. 425 if (ThreadLocalStorage::is_initialized()) { 426 // The JNI_OnLoad handling is normally done by method load in 427 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 428 // explicitly so we have to check for JNI_OnLoad as well 429 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 430 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 431 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 432 if (JNI_OnLoad != NULL) { 433 JavaThread* thread = JavaThread::current(); 434 ThreadToNativeFromVM ttn(thread); 435 HandleMark hm(thread); 436 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 437 onLoaded = JNI_TRUE; 438 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 439 vm_exit_during_initialization("Unsupported JNI version"); 440 } 441 } 442 } 443 } 444 return _native_java_library; 445} 446 447/* 448 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 449 * If check_lib == true then we are looking for an 450 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 451 * this library is statically linked into the image. 452 * If check_lib == false then we will look for the appropriate symbol in the 453 * executable if agent_lib->is_static_lib() == true or in the shared library 454 * referenced by 'handle'. 455 */ 456void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 457 const char *syms[], size_t syms_len) { 458 assert(agent_lib != NULL, "sanity check"); 459 const char *lib_name; 460 void *handle = agent_lib->os_lib(); 461 void *entryName = NULL; 462 char *agent_function_name; 463 size_t i; 464 465 // If checking then use the agent name otherwise test is_static_lib() to 466 // see how to process this lookup 467 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 468 for (i = 0; i < syms_len; i++) { 469 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 470 if (agent_function_name == NULL) { 471 break; 472 } 473 entryName = dll_lookup(handle, agent_function_name); 474 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread); 475 if (entryName != NULL) { 476 break; 477 } 478 } 479 return entryName; 480} 481 482// See if the passed in agent is statically linked into the VM image. 483bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 484 size_t syms_len) { 485 void *ret; 486 void *proc_handle; 487 void *save_handle; 488 489 assert(agent_lib != NULL, "sanity check"); 490 if (agent_lib->name() == NULL) { 491 return false; 492 } 493 proc_handle = get_default_process_handle(); 494 // Check for Agent_OnLoad/Attach_lib_name function 495 save_handle = agent_lib->os_lib(); 496 // We want to look in this process' symbol table. 497 agent_lib->set_os_lib(proc_handle); 498 ret = find_agent_function(agent_lib, true, syms, syms_len); 499 if (ret != NULL) { 500 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 501 agent_lib->set_valid(); 502 agent_lib->set_static_lib(true); 503 return true; 504 } 505 agent_lib->set_os_lib(save_handle); 506 return false; 507} 508 509// --------------------- heap allocation utilities --------------------- 510 511char *os::strdup(const char *str, MEMFLAGS flags) { 512 size_t size = strlen(str); 513 char *dup_str = (char *)malloc(size + 1, flags); 514 if (dup_str == NULL) return NULL; 515 strcpy(dup_str, str); 516 return dup_str; 517} 518 519 520#define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 521 522#ifdef ASSERT 523 524static void verify_memory(void* ptr) { 525 GuardedMemory guarded(ptr); 526 if (!guarded.verify_guards()) { 527 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 528 tty->print_cr("## memory stomp:"); 529 guarded.print_on(tty); 530 fatal("memory stomping error"); 531 } 532} 533 534#endif 535 536// 537// This function supports testing of the malloc out of memory 538// condition without really running the system out of memory. 539// 540static u_char* testMalloc(size_t alloc_size) { 541 assert(MallocMaxTestWords > 0, "sanity check"); 542 543 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 544 return NULL; 545 } 546 547 u_char* ptr = (u_char*)::malloc(alloc_size); 548 549 if (ptr != NULL) { 550 Atomic::add(((jint) (alloc_size / BytesPerWord)), 551 (volatile jint *) &cur_malloc_words); 552 } 553 return ptr; 554} 555 556void* os::malloc(size_t size, MEMFLAGS memflags, address caller) { 557 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 558 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 559 560#ifdef ASSERT 561 // checking for the WatcherThread and crash_protection first 562 // since os::malloc can be called when the libjvm.{dll,so} is 563 // first loaded and we don't have a thread yet. 564 // try to find the thread after we see that the watcher thread 565 // exists and has crash protection. 566 WatcherThread *wt = WatcherThread::watcher_thread(); 567 if (wt != NULL && wt->has_crash_protection()) { 568 Thread* thread = ThreadLocalStorage::get_thread_slow(); 569 if (thread == wt) { 570 assert(!wt->has_crash_protection(), 571 "Can't malloc with crash protection from WatcherThread"); 572 } 573 } 574#endif 575 576 if (size == 0) { 577 // return a valid pointer if size is zero 578 // if NULL is returned the calling functions assume out of memory. 579 size = 1; 580 } 581 582#ifndef ASSERT 583 const size_t alloc_size = size; 584#else 585 const size_t alloc_size = GuardedMemory::get_total_size(size); 586 if (size > alloc_size) { // Check for rollover. 587 return NULL; 588 } 589#endif 590 591 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 592 593 u_char* ptr; 594 if (MallocMaxTestWords > 0) { 595 ptr = testMalloc(alloc_size); 596 } else { 597 ptr = (u_char*)::malloc(alloc_size); 598 } 599 600#ifdef ASSERT 601 if (ptr == NULL) { 602 return NULL; 603 } 604 // Wrap memory with guard 605 GuardedMemory guarded(ptr, size); 606 ptr = guarded.get_user_ptr(); 607#endif 608 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 609 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 610 breakpoint(); 611 } 612 debug_only(if (paranoid) verify_memory(ptr)); 613 if (PrintMalloc && tty != NULL) { 614 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 615 } 616 617 // we do not track guard memory 618 MemTracker::record_malloc((address)ptr, size, memflags, caller == 0 ? CALLER_PC : caller); 619 620 return ptr; 621} 622 623 624void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) { 625#ifndef ASSERT 626 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 627 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 628 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker(); 629 void* ptr = ::realloc(memblock, size); 630 if (ptr != NULL) { 631 tkr.record((address)memblock, (address)ptr, size, memflags, 632 caller == 0 ? CALLER_PC : caller); 633 } else { 634 tkr.discard(); 635 } 636 return ptr; 637#else 638 if (memblock == NULL) { 639 return os::malloc(size, memflags, (caller == 0 ? CALLER_PC : caller)); 640 } 641 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 642 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 643 breakpoint(); 644 } 645 verify_memory(memblock); 646 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 647 if (size == 0) { 648 return NULL; 649 } 650 // always move the block 651 void* ptr = os::malloc(size, memflags, caller == 0 ? CALLER_PC : caller); 652 if (PrintMalloc) { 653 tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 654 } 655 // Copy to new memory if malloc didn't fail 656 if ( ptr != NULL ) { 657 GuardedMemory guarded(memblock); 658 memcpy(ptr, memblock, MIN2(size, guarded.get_user_size())); 659 if (paranoid) verify_memory(ptr); 660 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 661 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 662 breakpoint(); 663 } 664 os::free(memblock); 665 } 666 return ptr; 667#endif 668} 669 670 671void os::free(void *memblock, MEMFLAGS memflags) { 672 address trackp = (address) memblock; 673 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 674#ifdef ASSERT 675 if (memblock == NULL) return; 676 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 677 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 678 breakpoint(); 679 } 680 verify_memory(memblock); 681 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 682 683 GuardedMemory guarded(memblock); 684 size_t size = guarded.get_user_size(); 685 inc_stat_counter(&free_bytes, size); 686 memblock = guarded.release_for_freeing(); 687 if (PrintMalloc && tty != NULL) { 688 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 689 } 690#endif 691 MemTracker::record_free(trackp, memflags); 692 693 ::free(memblock); 694} 695 696void os::init_random(long initval) { 697 _rand_seed = initval; 698} 699 700 701long os::random() { 702 /* standard, well-known linear congruential random generator with 703 * next_rand = (16807*seed) mod (2**31-1) 704 * see 705 * (1) "Random Number Generators: Good Ones Are Hard to Find", 706 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 707 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 708 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 709 */ 710 const long a = 16807; 711 const unsigned long m = 2147483647; 712 const long q = m / a; assert(q == 127773, "weird math"); 713 const long r = m % a; assert(r == 2836, "weird math"); 714 715 // compute az=2^31p+q 716 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 717 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 718 lo += (hi & 0x7FFF) << 16; 719 720 // if q overflowed, ignore the overflow and increment q 721 if (lo > m) { 722 lo &= m; 723 ++lo; 724 } 725 lo += hi >> 15; 726 727 // if (p+q) overflowed, ignore the overflow and increment (p+q) 728 if (lo > m) { 729 lo &= m; 730 ++lo; 731 } 732 return (_rand_seed = lo); 733} 734 735// The INITIALIZED state is distinguished from the SUSPENDED state because the 736// conditions in which a thread is first started are different from those in which 737// a suspension is resumed. These differences make it hard for us to apply the 738// tougher checks when starting threads that we want to do when resuming them. 739// However, when start_thread is called as a result of Thread.start, on a Java 740// thread, the operation is synchronized on the Java Thread object. So there 741// cannot be a race to start the thread and hence for the thread to exit while 742// we are working on it. Non-Java threads that start Java threads either have 743// to do so in a context in which races are impossible, or should do appropriate 744// locking. 745 746void os::start_thread(Thread* thread) { 747 // guard suspend/resume 748 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 749 OSThread* osthread = thread->osthread(); 750 osthread->set_state(RUNNABLE); 751 pd_start_thread(thread); 752} 753 754//--------------------------------------------------------------------------- 755// Helper functions for fatal error handler 756 757void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 758 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 759 760 int cols = 0; 761 int cols_per_line = 0; 762 switch (unitsize) { 763 case 1: cols_per_line = 16; break; 764 case 2: cols_per_line = 8; break; 765 case 4: cols_per_line = 4; break; 766 case 8: cols_per_line = 2; break; 767 default: return; 768 } 769 770 address p = start; 771 st->print(PTR_FORMAT ": ", start); 772 while (p < end) { 773 switch (unitsize) { 774 case 1: st->print("%02x", *(u1*)p); break; 775 case 2: st->print("%04x", *(u2*)p); break; 776 case 4: st->print("%08x", *(u4*)p); break; 777 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 778 } 779 p += unitsize; 780 cols++; 781 if (cols >= cols_per_line && p < end) { 782 cols = 0; 783 st->cr(); 784 st->print(PTR_FORMAT ": ", p); 785 } else { 786 st->print(" "); 787 } 788 } 789 st->cr(); 790} 791 792void os::print_environment_variables(outputStream* st, const char** env_list, 793 char* buffer, int len) { 794 if (env_list) { 795 st->print_cr("Environment Variables:"); 796 797 for (int i = 0; env_list[i] != NULL; i++) { 798 if (getenv(env_list[i], buffer, len)) { 799 st->print("%s", env_list[i]); 800 st->print("="); 801 st->print_cr("%s", buffer); 802 } 803 } 804 } 805} 806 807void os::print_cpu_info(outputStream* st) { 808 // cpu 809 st->print("CPU:"); 810 st->print("total %d", os::processor_count()); 811 // It's not safe to query number of active processors after crash 812 // st->print("(active %d)", os::active_processor_count()); 813 st->print(" %s", VM_Version::cpu_features()); 814 st->cr(); 815 pd_print_cpu_info(st); 816} 817 818void os::print_date_and_time(outputStream *st) { 819 const int secs_per_day = 86400; 820 const int secs_per_hour = 3600; 821 const int secs_per_min = 60; 822 823 time_t tloc; 824 (void)time(&tloc); 825 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 826 827 double t = os::elapsedTime(); 828 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 829 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 830 // before printf. We lost some precision, but who cares? 831 int eltime = (int)t; // elapsed time in seconds 832 833 // print elapsed time in a human-readable format: 834 int eldays = eltime / secs_per_day; 835 int day_secs = eldays * secs_per_day; 836 int elhours = (eltime - day_secs) / secs_per_hour; 837 int hour_secs = elhours * secs_per_hour; 838 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 839 int minute_secs = elmins * secs_per_min; 840 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 841 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 842} 843 844// moved from debug.cpp (used to be find()) but still called from there 845// The verbose parameter is only set by the debug code in one case 846void os::print_location(outputStream* st, intptr_t x, bool verbose) { 847 address addr = (address)x; 848 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 849 if (b != NULL) { 850 if (b->is_buffer_blob()) { 851 // the interpreter is generated into a buffer blob 852 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 853 if (i != NULL) { 854 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 855 i->print_on(st); 856 return; 857 } 858 if (Interpreter::contains(addr)) { 859 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 860 " (not bytecode specific)", addr); 861 return; 862 } 863 // 864 if (AdapterHandlerLibrary::contains(b)) { 865 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 866 AdapterHandlerLibrary::print_handler_on(st, b); 867 } 868 // the stubroutines are generated into a buffer blob 869 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 870 if (d != NULL) { 871 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 872 d->print_on(st); 873 st->cr(); 874 return; 875 } 876 if (StubRoutines::contains(addr)) { 877 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 878 "stub routine", addr); 879 return; 880 } 881 // the InlineCacheBuffer is using stubs generated into a buffer blob 882 if (InlineCacheBuffer::contains(addr)) { 883 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 884 return; 885 } 886 VtableStub* v = VtableStubs::stub_containing(addr); 887 if (v != NULL) { 888 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 889 v->print_on(st); 890 st->cr(); 891 return; 892 } 893 } 894 nmethod* nm = b->as_nmethod_or_null(); 895 if (nm != NULL) { 896 ResourceMark rm; 897 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 898 addr, (int)(addr - nm->entry_point()), nm); 899 if (verbose) { 900 st->print(" for "); 901 nm->method()->print_value_on(st); 902 } 903 st->cr(); 904 nm->print_nmethod(verbose); 905 return; 906 } 907 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 908 b->print_on(st); 909 return; 910 } 911 912 if (Universe::heap()->is_in(addr)) { 913 HeapWord* p = Universe::heap()->block_start(addr); 914 bool print = false; 915 // If we couldn't find it it just may mean that heap wasn't parsable 916 // See if we were just given an oop directly 917 if (p != NULL && Universe::heap()->block_is_obj(p)) { 918 print = true; 919 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 920 p = (HeapWord*) addr; 921 print = true; 922 } 923 if (print) { 924 if (p == (HeapWord*) addr) { 925 st->print_cr(INTPTR_FORMAT " is an oop", addr); 926 } else { 927 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 928 } 929 oop(p)->print_on(st); 930 return; 931 } 932 } else { 933 if (Universe::heap()->is_in_reserved(addr)) { 934 st->print_cr(INTPTR_FORMAT " is an unallocated location " 935 "in the heap", addr); 936 return; 937 } 938 } 939 if (JNIHandles::is_global_handle((jobject) addr)) { 940 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 941 return; 942 } 943 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 944 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 945 return; 946 } 947#ifndef PRODUCT 948 // we don't keep the block list in product mode 949 if (JNIHandleBlock::any_contains((jobject) addr)) { 950 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 951 return; 952 } 953#endif 954 955 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 956 // Check for privilege stack 957 if (thread->privileged_stack_top() != NULL && 958 thread->privileged_stack_top()->contains(addr)) { 959 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 960 "for thread: " INTPTR_FORMAT, addr, thread); 961 if (verbose) thread->print_on(st); 962 return; 963 } 964 // If the addr is a java thread print information about that. 965 if (addr == (address)thread) { 966 if (verbose) { 967 thread->print_on(st); 968 } else { 969 st->print_cr(INTPTR_FORMAT " is a thread", addr); 970 } 971 return; 972 } 973 // If the addr is in the stack region for this thread then report that 974 // and print thread info 975 if (thread->stack_base() >= addr && 976 addr > (thread->stack_base() - thread->stack_size())) { 977 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 978 INTPTR_FORMAT, addr, thread); 979 if (verbose) thread->print_on(st); 980 return; 981 } 982 983 } 984 985 // Check if in metaspace and print types that have vptrs (only method now) 986 if (Metaspace::contains(addr)) { 987 if (Method::has_method_vptr((const void*)addr)) { 988 ((Method*)addr)->print_value_on(st); 989 st->cr(); 990 } else { 991 // Use addr->print() from the debugger instead (not here) 992 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr); 993 } 994 return; 995 } 996 997 // Try an OS specific find 998 if (os::find(addr, st)) { 999 return; 1000 } 1001 1002 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1003} 1004 1005// Looks like all platforms except IA64 can use the same function to check 1006// if C stack is walkable beyond current frame. The check for fp() is not 1007// necessary on Sparc, but it's harmless. 1008bool os::is_first_C_frame(frame* fr) { 1009#if (defined(IA64) && !defined(AIX)) && !defined(_WIN32) 1010 // On IA64 we have to check if the callers bsp is still valid 1011 // (i.e. within the register stack bounds). 1012 // Notice: this only works for threads created by the VM and only if 1013 // we walk the current stack!!! If we want to be able to walk 1014 // arbitrary other threads, we'll have to somehow store the thread 1015 // object in the frame. 1016 Thread *thread = Thread::current(); 1017 if ((address)fr->fp() <= 1018 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1019 // This check is a little hacky, because on Linux the first C 1020 // frame's ('start_thread') register stack frame starts at 1021 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1022 // ('__pthread_bound_body') register stack frame seems to really 1023 // start at "register_stack_base". 1024 return true; 1025 } else { 1026 return false; 1027 } 1028#elif defined(IA64) && defined(_WIN32) 1029 return true; 1030#else 1031 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1032 // Check usp first, because if that's bad the other accessors may fault 1033 // on some architectures. Ditto ufp second, etc. 1034 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1035 // sp on amd can be 32 bit aligned. 1036 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1037 1038 uintptr_t usp = (uintptr_t)fr->sp(); 1039 if ((usp & sp_align_mask) != 0) return true; 1040 1041 uintptr_t ufp = (uintptr_t)fr->fp(); 1042 if ((ufp & fp_align_mask) != 0) return true; 1043 1044 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1045 if ((old_sp & sp_align_mask) != 0) return true; 1046 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1047 1048 uintptr_t old_fp = (uintptr_t)fr->link(); 1049 if ((old_fp & fp_align_mask) != 0) return true; 1050 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1051 1052 // stack grows downwards; if old_fp is below current fp or if the stack 1053 // frame is too large, either the stack is corrupted or fp is not saved 1054 // on stack (i.e. on x86, ebp may be used as general register). The stack 1055 // is not walkable beyond current frame. 1056 if (old_fp < ufp) return true; 1057 if (old_fp - ufp > 64 * K) return true; 1058 1059 return false; 1060#endif 1061} 1062 1063#ifdef ASSERT 1064extern "C" void test_random() { 1065 const double m = 2147483647; 1066 double mean = 0.0, variance = 0.0, t; 1067 long reps = 10000; 1068 unsigned long seed = 1; 1069 1070 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1071 os::init_random(seed); 1072 long num; 1073 for (int k = 0; k < reps; k++) { 1074 num = os::random(); 1075 double u = (double)num / m; 1076 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1077 1078 // calculate mean and variance of the random sequence 1079 mean += u; 1080 variance += (u*u); 1081 } 1082 mean /= reps; 1083 variance /= (reps - 1); 1084 1085 assert(num == 1043618065, "bad seed"); 1086 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1087 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1088 const double eps = 0.0001; 1089 t = fabsd(mean - 0.5018); 1090 assert(t < eps, "bad mean"); 1091 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1092 assert(t < eps, "bad variance"); 1093} 1094#endif 1095 1096 1097// Set up the boot classpath. 1098 1099char* os::format_boot_path(const char* format_string, 1100 const char* home, 1101 int home_len, 1102 char fileSep, 1103 char pathSep) { 1104 assert((fileSep == '/' && pathSep == ':') || 1105 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1106 1107 // Scan the format string to determine the length of the actual 1108 // boot classpath, and handle platform dependencies as well. 1109 int formatted_path_len = 0; 1110 const char* p; 1111 for (p = format_string; *p != 0; ++p) { 1112 if (*p == '%') formatted_path_len += home_len - 1; 1113 ++formatted_path_len; 1114 } 1115 1116 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1117 if (formatted_path == NULL) { 1118 return NULL; 1119 } 1120 1121 // Create boot classpath from format, substituting separator chars and 1122 // java home directory. 1123 char* q = formatted_path; 1124 for (p = format_string; *p != 0; ++p) { 1125 switch (*p) { 1126 case '%': 1127 strcpy(q, home); 1128 q += home_len; 1129 break; 1130 case '/': 1131 *q++ = fileSep; 1132 break; 1133 case ':': 1134 *q++ = pathSep; 1135 break; 1136 default: 1137 *q++ = *p; 1138 } 1139 } 1140 *q = '\0'; 1141 1142 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1143 return formatted_path; 1144} 1145 1146 1147bool os::set_boot_path(char fileSep, char pathSep) { 1148 const char* home = Arguments::get_java_home(); 1149 int home_len = (int)strlen(home); 1150 1151 static const char* meta_index_dir_format = "%/lib/"; 1152 static const char* meta_index_format = "%/lib/meta-index"; 1153 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1154 if (meta_index == NULL) return false; 1155 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1156 if (meta_index_dir == NULL) return false; 1157 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1158 1159 // Any modification to the JAR-file list, for the boot classpath must be 1160 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1161 // path class JARs, are stripped for StackMapTable to reduce download size. 1162 static const char classpath_format[] = 1163 "%/lib/resources.jar:" 1164 "%/lib/rt.jar:" 1165 "%/lib/sunrsasign.jar:" 1166 "%/lib/jsse.jar:" 1167 "%/lib/jce.jar:" 1168 "%/lib/charsets.jar:" 1169 "%/lib/jfr.jar:" 1170 "%/classes"; 1171 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1172 if (sysclasspath == NULL) return false; 1173 Arguments::set_sysclasspath(sysclasspath); 1174 1175 return true; 1176} 1177 1178/* 1179 * Splits a path, based on its separator, the number of 1180 * elements is returned back in n. 1181 * It is the callers responsibility to: 1182 * a> check the value of n, and n may be 0. 1183 * b> ignore any empty path elements 1184 * c> free up the data. 1185 */ 1186char** os::split_path(const char* path, int* n) { 1187 *n = 0; 1188 if (path == NULL || strlen(path) == 0) { 1189 return NULL; 1190 } 1191 const char psepchar = *os::path_separator(); 1192 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1193 if (inpath == NULL) { 1194 return NULL; 1195 } 1196 strcpy(inpath, path); 1197 int count = 1; 1198 char* p = strchr(inpath, psepchar); 1199 // Get a count of elements to allocate memory 1200 while (p != NULL) { 1201 count++; 1202 p++; 1203 p = strchr(p, psepchar); 1204 } 1205 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1206 if (opath == NULL) { 1207 return NULL; 1208 } 1209 1210 // do the actual splitting 1211 p = inpath; 1212 for (int i = 0 ; i < count ; i++) { 1213 size_t len = strcspn(p, os::path_separator()); 1214 if (len > JVM_MAXPATHLEN) { 1215 return NULL; 1216 } 1217 // allocate the string and add terminator storage 1218 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1219 if (s == NULL) { 1220 return NULL; 1221 } 1222 strncpy(s, p, len); 1223 s[len] = '\0'; 1224 opath[i] = s; 1225 p += len + 1; 1226 } 1227 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1228 *n = count; 1229 return opath; 1230} 1231 1232void os::set_memory_serialize_page(address page) { 1233 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1234 _mem_serialize_page = (volatile int32_t *)page; 1235 // We initialize the serialization page shift count here 1236 // We assume a cache line size of 64 bytes 1237 assert(SerializePageShiftCount == count, 1238 "thread size changed, fix SerializePageShiftCount constant"); 1239 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1240} 1241 1242static volatile intptr_t SerializePageLock = 0; 1243 1244// This method is called from signal handler when SIGSEGV occurs while the current 1245// thread tries to store to the "read-only" memory serialize page during state 1246// transition. 1247void os::block_on_serialize_page_trap() { 1248 if (TraceSafepoint) { 1249 tty->print_cr("Block until the serialize page permission restored"); 1250 } 1251 // When VMThread is holding the SerializePageLock during modifying the 1252 // access permission of the memory serialize page, the following call 1253 // will block until the permission of that page is restored to rw. 1254 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1255 // this case, it's OK as the signal is synchronous and we know precisely when 1256 // it can occur. 1257 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1258 Thread::muxRelease(&SerializePageLock); 1259} 1260 1261// Serialize all thread state variables 1262void os::serialize_thread_states() { 1263 // On some platforms such as Solaris & Linux, the time duration of the page 1264 // permission restoration is observed to be much longer than expected due to 1265 // scheduler starvation problem etc. To avoid the long synchronization 1266 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1267 // the mutator thread if such case is encountered. See bug 6546278 for details. 1268 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1269 os::protect_memory((char *)os::get_memory_serialize_page(), 1270 os::vm_page_size(), MEM_PROT_READ); 1271 os::protect_memory((char *)os::get_memory_serialize_page(), 1272 os::vm_page_size(), MEM_PROT_RW); 1273 Thread::muxRelease(&SerializePageLock); 1274} 1275 1276// Returns true if the current stack pointer is above the stack shadow 1277// pages, false otherwise. 1278 1279bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1280 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1281 address sp = current_stack_pointer(); 1282 // Check if we have StackShadowPages above the yellow zone. This parameter 1283 // is dependent on the depth of the maximum VM call stack possible from 1284 // the handler for stack overflow. 'instanceof' in the stack overflow 1285 // handler or a println uses at least 8k stack of VM and native code 1286 // respectively. 1287 const int framesize_in_bytes = 1288 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1289 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1290 * vm_page_size()) + framesize_in_bytes; 1291 // The very lower end of the stack 1292 address stack_limit = thread->stack_base() - thread->stack_size(); 1293 return (sp > (stack_limit + reserved_area)); 1294} 1295 1296size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1297 uint min_pages) 1298{ 1299 assert(min_pages > 0, "sanity"); 1300 if (UseLargePages) { 1301 const size_t max_page_size = region_max_size / min_pages; 1302 1303 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1304 const size_t sz = _page_sizes[i]; 1305 const size_t mask = sz - 1; 1306 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1307 // The largest page size with no fragmentation. 1308 return sz; 1309 } 1310 1311 if (sz <= max_page_size) { 1312 // The largest page size that satisfies the min_pages requirement. 1313 return sz; 1314 } 1315 } 1316 } 1317 1318 return vm_page_size(); 1319} 1320 1321#ifndef PRODUCT 1322void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1323{ 1324 if (TracePageSizes) { 1325 tty->print("%s: ", str); 1326 for (int i = 0; i < count; ++i) { 1327 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1328 } 1329 tty->cr(); 1330 } 1331} 1332 1333void os::trace_page_sizes(const char* str, const size_t region_min_size, 1334 const size_t region_max_size, const size_t page_size, 1335 const char* base, const size_t size) 1336{ 1337 if (TracePageSizes) { 1338 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1339 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1340 " size=" SIZE_FORMAT, 1341 str, region_min_size, region_max_size, 1342 page_size, base, size); 1343 } 1344} 1345#endif // #ifndef PRODUCT 1346 1347// This is the working definition of a server class machine: 1348// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1349// because the graphics memory (?) sometimes masks physical memory. 1350// If you want to change the definition of a server class machine 1351// on some OS or platform, e.g., >=4GB on Windows platforms, 1352// then you'll have to parameterize this method based on that state, 1353// as was done for logical processors here, or replicate and 1354// specialize this method for each platform. (Or fix os to have 1355// some inheritance structure and use subclassing. Sigh.) 1356// If you want some platform to always or never behave as a server 1357// class machine, change the setting of AlwaysActAsServerClassMachine 1358// and NeverActAsServerClassMachine in globals*.hpp. 1359bool os::is_server_class_machine() { 1360 // First check for the early returns 1361 if (NeverActAsServerClassMachine) { 1362 return false; 1363 } 1364 if (AlwaysActAsServerClassMachine) { 1365 return true; 1366 } 1367 // Then actually look at the machine 1368 bool result = false; 1369 const unsigned int server_processors = 2; 1370 const julong server_memory = 2UL * G; 1371 // We seem not to get our full complement of memory. 1372 // We allow some part (1/8?) of the memory to be "missing", 1373 // based on the sizes of DIMMs, and maybe graphics cards. 1374 const julong missing_memory = 256UL * M; 1375 1376 /* Is this a server class machine? */ 1377 if ((os::active_processor_count() >= (int)server_processors) && 1378 (os::physical_memory() >= (server_memory - missing_memory))) { 1379 const unsigned int logical_processors = 1380 VM_Version::logical_processors_per_package(); 1381 if (logical_processors > 1) { 1382 const unsigned int physical_packages = 1383 os::active_processor_count() / logical_processors; 1384 if (physical_packages > server_processors) { 1385 result = true; 1386 } 1387 } else { 1388 result = true; 1389 } 1390 } 1391 return result; 1392} 1393 1394void os::SuspendedThreadTask::run() { 1395 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1396 internal_do_task(); 1397 _done = true; 1398} 1399 1400bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1401 return os::pd_create_stack_guard_pages(addr, bytes); 1402} 1403 1404char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1405 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1406 if (result != NULL) { 1407 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1408 } 1409 1410 return result; 1411} 1412 1413char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1414 MEMFLAGS flags) { 1415 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1416 if (result != NULL) { 1417 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1418 MemTracker::record_virtual_memory_type((address)result, flags); 1419 } 1420 1421 return result; 1422} 1423 1424char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1425 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1426 if (result != NULL) { 1427 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1428 } 1429 return result; 1430} 1431 1432void os::split_reserved_memory(char *base, size_t size, 1433 size_t split, bool realloc) { 1434 pd_split_reserved_memory(base, size, split, realloc); 1435} 1436 1437bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1438 bool res = pd_commit_memory(addr, bytes, executable); 1439 if (res) { 1440 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1441 } 1442 return res; 1443} 1444 1445bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1446 bool executable) { 1447 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1448 if (res) { 1449 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1450 } 1451 return res; 1452} 1453 1454void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1455 const char* mesg) { 1456 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1457 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1458} 1459 1460void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1461 bool executable, const char* mesg) { 1462 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1463 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1464} 1465 1466bool os::uncommit_memory(char* addr, size_t bytes) { 1467 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1468 bool res = pd_uncommit_memory(addr, bytes); 1469 if (res) { 1470 tkr.record((address)addr, bytes); 1471 } else { 1472 tkr.discard(); 1473 } 1474 return res; 1475} 1476 1477bool os::release_memory(char* addr, size_t bytes) { 1478 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1479 bool res = pd_release_memory(addr, bytes); 1480 if (res) { 1481 tkr.record((address)addr, bytes); 1482 } else { 1483 tkr.discard(); 1484 } 1485 return res; 1486} 1487 1488 1489char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1490 char *addr, size_t bytes, bool read_only, 1491 bool allow_exec) { 1492 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1493 if (result != NULL) { 1494 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC); 1495 } 1496 return result; 1497} 1498 1499char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1500 char *addr, size_t bytes, bool read_only, 1501 bool allow_exec) { 1502 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1503 read_only, allow_exec); 1504} 1505 1506bool os::unmap_memory(char *addr, size_t bytes) { 1507 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1508 bool result = pd_unmap_memory(addr, bytes); 1509 if (result) { 1510 tkr.record((address)addr, bytes); 1511 } else { 1512 tkr.discard(); 1513 } 1514 return result; 1515} 1516 1517void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1518 pd_free_memory(addr, bytes, alignment_hint); 1519} 1520 1521void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1522 pd_realign_memory(addr, bytes, alignment_hint); 1523} 1524 1525#ifndef TARGET_OS_FAMILY_windows 1526/* try to switch state from state "from" to state "to" 1527 * returns the state set after the method is complete 1528 */ 1529os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1530 os::SuspendResume::State to) 1531{ 1532 os::SuspendResume::State result = 1533 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1534 if (result == from) { 1535 // success 1536 return to; 1537 } 1538 return result; 1539} 1540#endif 1541