1 /* 2 * Copyright (c) 1997, 2015, 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/shared/vmGCOperations.hpp" 34 #include "interpreter/interpreter.hpp" 35 #include "logging/log.hpp" 36 #include "memory/allocation.inline.hpp" 37 #ifdef ASSERT 38 #include "memory/guardedMemory.hpp" 39 #endif 40 #include "oops/oop.inline.hpp" 41 #include "prims/jvm.h" 42 #include "prims/jvm_misc.hpp" 43 #include "prims/privilegedStack.hpp" 44 #include "runtime/arguments.hpp" 45 #include "runtime/atomic.inline.hpp" 46 #include "runtime/frame.inline.hpp" 47 #include "runtime/interfaceSupport.hpp" 48 #include "runtime/java.hpp" 49 #include "runtime/javaCalls.hpp" 50 #include "runtime/mutexLocker.hpp" 51 #include "runtime/os.inline.hpp" 52 #include "runtime/stubRoutines.hpp" 53 #include "runtime/thread.inline.hpp" 54 #include "runtime/vm_version.hpp" 55 #include "services/attachListener.hpp" 56 #include "services/mallocTracker.hpp" 57 #include "services/memTracker.hpp" 58 #include "services/nmtCommon.hpp" 59 #include "services/threadService.hpp" 60 #include "utilities/defaultStream.hpp" 61 #include "utilities/events.hpp" 62 63 # include <signal.h> 64 65 OSThread* os::_starting_thread = NULL; 66 address os::_polling_page = NULL; 67 volatile int32_t* os::_mem_serialize_page = NULL; 68 uintptr_t os::_serialize_page_mask = 0; 69 long os::_rand_seed = 1; 70 int os::_processor_count = 0; 71 size_t os::_page_sizes[os::page_sizes_max]; 72 73 #ifndef PRODUCT 74 julong os::num_mallocs = 0; // # of calls to malloc/realloc 75 julong os::alloc_bytes = 0; // # of bytes allocated 76 julong os::num_frees = 0; // # of calls to free 77 julong os::free_bytes = 0; // # of bytes freed 78 #endif 79 80 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords 81 82 void os_init_globals() { 83 // Called from init_globals(). 84 // See Threads::create_vm() in thread.cpp, and init.cpp. 85 os::init_globals(); 86 } 87 88 // Fill in buffer with current local time as an ISO-8601 string. 89 // E.g., yyyy-mm-ddThh:mm:ss-zzzz. 90 // Returns buffer, or NULL if it failed. 91 // This would mostly be a call to 92 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 93 // except that on Windows the %z behaves badly, so we do it ourselves. 94 // Also, people wanted milliseconds on there, 95 // and strftime doesn't do milliseconds. 96 char* os::iso8601_time(char* buffer, size_t buffer_length) { 97 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 98 // 1 2 99 // 12345678901234567890123456789 100 // format string: "%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, 162 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d", 163 year, 164 month, 165 time_struct.tm_mday, 166 time_struct.tm_hour, 167 time_struct.tm_min, 168 time_struct.tm_sec, 169 milliseconds_after_second, 170 sign_local_to_UTC, 171 zone_hours, 172 zone_min); 173 if (printed == 0) { 174 assert(false, "Failed jio_printf"); 175 return NULL; 176 } 177 return buffer; 178 } 179 180 OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 181 #ifdef ASSERT 182 if (!(!thread->is_Java_thread() || 183 Thread::current() == thread || 184 Threads_lock->owned_by_self() 185 || thread->is_Compiler_thread() 186 )) { 187 assert(false, "possibility of dangling Thread pointer"); 188 } 189 #endif 190 191 if (p >= MinPriority && p <= MaxPriority) { 192 int priority = java_to_os_priority[p]; 193 return set_native_priority(thread, priority); 194 } else { 195 assert(false, "Should not happen"); 196 return OS_ERR; 197 } 198 } 199 200 // The mapping from OS priority back to Java priority may be inexact because 201 // Java priorities can map M:1 with native priorities. If you want the definite 202 // Java priority then use JavaThread::java_priority() 203 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 204 int p; 205 int os_prio; 206 OSReturn ret = get_native_priority(thread, &os_prio); 207 if (ret != OS_OK) return ret; 208 209 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 210 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 211 } else { 212 // niceness values are in reverse order 213 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 214 } 215 priority = (ThreadPriority)p; 216 return OS_OK; 217 } 218 219 220 // --------------------- sun.misc.Signal (optional) --------------------- 221 222 223 // SIGBREAK is sent by the keyboard to query the VM state 224 #ifndef SIGBREAK 225 #define SIGBREAK SIGQUIT 226 #endif 227 228 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 229 230 231 static void signal_thread_entry(JavaThread* thread, TRAPS) { 232 os::set_priority(thread, NearMaxPriority); 233 while (true) { 234 int sig; 235 { 236 // FIXME : Currently we have not decided what should be the status 237 // for this java thread blocked here. Once we decide about 238 // that we should fix this. 239 sig = os::signal_wait(); 240 } 241 if (sig == os::sigexitnum_pd()) { 242 // Terminate the signal thread 243 return; 244 } 245 246 switch (sig) { 247 case SIGBREAK: { 248 // Check if the signal is a trigger to start the Attach Listener - in that 249 // case don't print stack traces. 250 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 251 continue; 252 } 253 // Print stack traces 254 // Any SIGBREAK operations added here should make sure to flush 255 // the output stream (e.g. tty->flush()) after output. See 4803766. 256 // Each module also prints an extra carriage return after its output. 257 VM_PrintThreads op; 258 VMThread::execute(&op); 259 VM_PrintJNI jni_op; 260 VMThread::execute(&jni_op); 261 VM_FindDeadlocks op1(tty); 262 VMThread::execute(&op1); 263 Universe::print_heap_at_SIGBREAK(); 264 if (PrintClassHistogram) { 265 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */); 266 VMThread::execute(&op1); 267 } 268 if (JvmtiExport::should_post_data_dump()) { 269 JvmtiExport::post_data_dump(); 270 } 271 break; 272 } 273 default: { 274 // Dispatch the signal to java 275 HandleMark hm(THREAD); 276 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 277 KlassHandle klass (THREAD, k); 278 if (klass.not_null()) { 279 JavaValue result(T_VOID); 280 JavaCallArguments args; 281 args.push_int(sig); 282 JavaCalls::call_static( 283 &result, 284 klass, 285 vmSymbols::dispatch_name(), 286 vmSymbols::int_void_signature(), 287 &args, 288 THREAD 289 ); 290 } 291 if (HAS_PENDING_EXCEPTION) { 292 // tty is initialized early so we don't expect it to be null, but 293 // if it is we can't risk doing an initialization that might 294 // trigger additional out-of-memory conditions 295 if (tty != NULL) { 296 char klass_name[256]; 297 char tmp_sig_name[16]; 298 const char* sig_name = "UNKNOWN"; 299 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 300 name()->as_klass_external_name(klass_name, 256); 301 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 302 sig_name = tmp_sig_name; 303 warning("Exception %s occurred dispatching signal %s to handler" 304 "- the VM may need to be forcibly terminated", 305 klass_name, sig_name ); 306 } 307 CLEAR_PENDING_EXCEPTION; 308 } 309 } 310 } 311 } 312 } 313 314 void os::init_before_ergo() { 315 // We need to initialize large page support here because ergonomics takes some 316 // decisions depending on large page support and the calculated large page size. 317 large_page_init(); 318 } 319 320 void os::signal_init() { 321 if (!ReduceSignalUsage) { 322 // Setup JavaThread for processing signals 323 EXCEPTION_MARK; 324 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 325 instanceKlassHandle klass (THREAD, k); 326 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 327 328 const char thread_name[] = "Signal Dispatcher"; 329 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 330 331 // Initialize thread_oop to put it into the system threadGroup 332 Handle thread_group (THREAD, Universe::system_thread_group()); 333 JavaValue result(T_VOID); 334 JavaCalls::call_special(&result, thread_oop, 335 klass, 336 vmSymbols::object_initializer_name(), 337 vmSymbols::threadgroup_string_void_signature(), 338 thread_group, 339 string, 340 CHECK); 341 342 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 343 JavaCalls::call_special(&result, 344 thread_group, 345 group, 346 vmSymbols::add_method_name(), 347 vmSymbols::thread_void_signature(), 348 thread_oop, // ARG 1 349 CHECK); 350 351 os::signal_init_pd(); 352 353 { MutexLocker mu(Threads_lock); 354 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 355 356 // At this point it may be possible that no osthread was created for the 357 // JavaThread due to lack of memory. We would have to throw an exception 358 // in that case. However, since this must work and we do not allow 359 // exceptions anyway, check and abort if this fails. 360 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 361 vm_exit_during_initialization("java.lang.OutOfMemoryError", 362 os::native_thread_creation_failed_msg()); 363 } 364 365 java_lang_Thread::set_thread(thread_oop(), signal_thread); 366 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 367 java_lang_Thread::set_daemon(thread_oop()); 368 369 signal_thread->set_threadObj(thread_oop()); 370 Threads::add(signal_thread); 371 Thread::start(signal_thread); 372 } 373 // Handle ^BREAK 374 os::signal(SIGBREAK, os::user_handler()); 375 } 376 } 377 378 379 void os::terminate_signal_thread() { 380 if (!ReduceSignalUsage) 381 signal_notify(sigexitnum_pd()); 382 } 383 384 385 // --------------------- loading libraries --------------------- 386 387 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 388 extern struct JavaVM_ main_vm; 389 390 static void* _native_java_library = NULL; 391 392 void* os::native_java_library() { 393 if (_native_java_library == NULL) { 394 char buffer[JVM_MAXPATHLEN]; 395 char ebuf[1024]; 396 397 // Try to load verify dll first. In 1.3 java dll depends on it and is not 398 // always able to find it when the loading executable is outside the JDK. 399 // In order to keep working with 1.2 we ignore any loading errors. 400 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 401 "verify")) { 402 dll_load(buffer, ebuf, sizeof(ebuf)); 403 } 404 405 // Load java dll 406 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 407 "java")) { 408 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 409 } 410 if (_native_java_library == NULL) { 411 vm_exit_during_initialization("Unable to load native library", ebuf); 412 } 413 414 #if defined(__OpenBSD__) 415 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 416 // ignore errors 417 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 418 "net")) { 419 dll_load(buffer, ebuf, sizeof(ebuf)); 420 } 421 #endif 422 } 423 static jboolean onLoaded = JNI_FALSE; 424 if (onLoaded) { 425 // We may have to wait to fire OnLoad until TLS is initialized. 426 if (ThreadLocalStorage::is_initialized()) { 427 // The JNI_OnLoad handling is normally done by method load in 428 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 429 // explicitly so we have to check for JNI_OnLoad as well 430 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 431 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 432 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 433 if (JNI_OnLoad != NULL) { 434 JavaThread* thread = JavaThread::current(); 435 ThreadToNativeFromVM ttn(thread); 436 HandleMark hm(thread); 437 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 438 onLoaded = JNI_TRUE; 439 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 440 vm_exit_during_initialization("Unsupported JNI version"); 441 } 442 } 443 } 444 } 445 return _native_java_library; 446 } 447 448 /* 449 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 450 * If check_lib == true then we are looking for an 451 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 452 * this library is statically linked into the image. 453 * If check_lib == false then we will look for the appropriate symbol in the 454 * executable if agent_lib->is_static_lib() == true or in the shared library 455 * referenced by 'handle'. 456 */ 457 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 458 const char *syms[], size_t syms_len) { 459 assert(agent_lib != NULL, "sanity check"); 460 const char *lib_name; 461 void *handle = agent_lib->os_lib(); 462 void *entryName = NULL; 463 char *agent_function_name; 464 size_t i; 465 466 // If checking then use the agent name otherwise test is_static_lib() to 467 // see how to process this lookup 468 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 469 for (i = 0; i < syms_len; i++) { 470 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 471 if (agent_function_name == NULL) { 472 break; 473 } 474 entryName = dll_lookup(handle, agent_function_name); 475 FREE_C_HEAP_ARRAY(char, agent_function_name); 476 if (entryName != NULL) { 477 break; 478 } 479 } 480 return entryName; 481 } 482 483 // See if the passed in agent is statically linked into the VM image. 484 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 485 size_t syms_len) { 486 void *ret; 487 void *proc_handle; 488 void *save_handle; 489 490 assert(agent_lib != NULL, "sanity check"); 491 if (agent_lib->name() == NULL) { 492 return false; 493 } 494 proc_handle = get_default_process_handle(); 495 // Check for Agent_OnLoad/Attach_lib_name function 496 save_handle = agent_lib->os_lib(); 497 // We want to look in this process' symbol table. 498 agent_lib->set_os_lib(proc_handle); 499 ret = find_agent_function(agent_lib, true, syms, syms_len); 500 if (ret != NULL) { 501 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 502 agent_lib->set_valid(); 503 agent_lib->set_static_lib(true); 504 return true; 505 } 506 agent_lib->set_os_lib(save_handle); 507 return false; 508 } 509 510 // --------------------- heap allocation utilities --------------------- 511 512 char *os::strdup(const char *str, MEMFLAGS flags) { 513 size_t size = strlen(str); 514 char *dup_str = (char *)malloc(size + 1, flags); 515 if (dup_str == NULL) return NULL; 516 strcpy(dup_str, str); 517 return dup_str; 518 } 519 520 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) { 521 char* p = os::strdup(str, flags); 522 if (p == NULL) { 523 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom"); 524 } 525 return p; 526 } 527 528 529 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 530 531 #ifdef ASSERT 532 533 static void verify_memory(void* ptr) { 534 GuardedMemory guarded(ptr); 535 if (!guarded.verify_guards()) { 536 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 537 tty->print_cr("## memory stomp:"); 538 guarded.print_on(tty); 539 fatal("memory stomping error"); 540 } 541 } 542 543 #endif 544 545 // 546 // This function supports testing of the malloc out of memory 547 // condition without really running the system out of memory. 548 // 549 static bool has_reached_max_malloc_test_peak(size_t alloc_size) { 550 if (MallocMaxTestWords > 0) { 551 jint words = (jint)(alloc_size / BytesPerWord); 552 553 if ((cur_malloc_words + words) > MallocMaxTestWords) { 554 return true; 555 } 556 Atomic::add(words, (volatile jint *)&cur_malloc_words); 557 } 558 return false; 559 } 560 561 void* os::malloc(size_t size, MEMFLAGS flags) { 562 return os::malloc(size, flags, CALLER_PC); 563 } 564 565 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 566 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 567 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 568 569 #ifdef ASSERT 570 // checking for the WatcherThread and crash_protection first 571 // since os::malloc can be called when the libjvm.{dll,so} is 572 // first loaded and we don't have a thread yet. 573 // try to find the thread after we see that the watcher thread 574 // exists and has crash protection. 575 WatcherThread *wt = WatcherThread::watcher_thread(); 576 if (wt != NULL && wt->has_crash_protection()) { 577 Thread* thread = ThreadLocalStorage::get_thread_slow(); 578 if (thread == wt) { 579 assert(!wt->has_crash_protection(), 580 "Can't malloc with crash protection from WatcherThread"); 581 } 582 } 583 #endif 584 585 if (size == 0) { 586 // return a valid pointer if size is zero 587 // if NULL is returned the calling functions assume out of memory. 588 size = 1; 589 } 590 591 // NMT support 592 NMT_TrackingLevel level = MemTracker::tracking_level(); 593 size_t nmt_header_size = MemTracker::malloc_header_size(level); 594 595 #ifndef ASSERT 596 const size_t alloc_size = size + nmt_header_size; 597 #else 598 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size); 599 if (size + nmt_header_size > alloc_size) { // Check for rollover. 600 return NULL; 601 } 602 #endif 603 604 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 605 606 // For the test flag -XX:MallocMaxTestWords 607 if (has_reached_max_malloc_test_peak(size)) { 608 return NULL; 609 } 610 611 u_char* ptr; 612 ptr = (u_char*)::malloc(alloc_size); 613 614 #ifdef ASSERT 615 if (ptr == NULL) { 616 return NULL; 617 } 618 // Wrap memory with guard 619 GuardedMemory guarded(ptr, size + nmt_header_size); 620 ptr = guarded.get_user_ptr(); 621 #endif 622 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 623 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 624 breakpoint(); 625 } 626 debug_only(if (paranoid) verify_memory(ptr)); 627 if (PrintMalloc && tty != NULL) { 628 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 629 } 630 631 // we do not track guard memory 632 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level); 633 } 634 635 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 636 return os::realloc(memblock, size, flags, CALLER_PC); 637 } 638 639 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 640 641 // For the test flag -XX:MallocMaxTestWords 642 if (has_reached_max_malloc_test_peak(size)) { 643 return NULL; 644 } 645 646 #ifndef ASSERT 647 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 648 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 649 // NMT support 650 void* membase = MemTracker::record_free(memblock); 651 NMT_TrackingLevel level = MemTracker::tracking_level(); 652 size_t nmt_header_size = MemTracker::malloc_header_size(level); 653 void* ptr = ::realloc(membase, size + nmt_header_size); 654 return MemTracker::record_malloc(ptr, size, memflags, stack, level); 655 #else 656 if (memblock == NULL) { 657 return os::malloc(size, memflags, stack); 658 } 659 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 660 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock)); 661 breakpoint(); 662 } 663 // NMT support 664 void* membase = MemTracker::malloc_base(memblock); 665 verify_memory(membase); 666 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 667 if (size == 0) { 668 return NULL; 669 } 670 // always move the block 671 void* ptr = os::malloc(size, memflags, stack); 672 if (PrintMalloc && tty != NULL) { 673 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr)); 674 } 675 // Copy to new memory if malloc didn't fail 676 if ( ptr != NULL ) { 677 GuardedMemory guarded(MemTracker::malloc_base(memblock)); 678 // Guard's user data contains NMT header 679 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock); 680 memcpy(ptr, memblock, MIN2(size, memblock_size)); 681 if (paranoid) verify_memory(MemTracker::malloc_base(ptr)); 682 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 683 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 684 breakpoint(); 685 } 686 os::free(memblock); 687 } 688 return ptr; 689 #endif 690 } 691 692 693 void os::free(void *memblock) { 694 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 695 #ifdef ASSERT 696 if (memblock == NULL) return; 697 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 698 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock)); 699 breakpoint(); 700 } 701 void* membase = MemTracker::record_free(memblock); 702 verify_memory(membase); 703 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 704 705 GuardedMemory guarded(membase); 706 size_t size = guarded.get_user_size(); 707 inc_stat_counter(&free_bytes, size); 708 membase = guarded.release_for_freeing(); 709 if (PrintMalloc && tty != NULL) { 710 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase); 711 } 712 ::free(membase); 713 #else 714 void* membase = MemTracker::record_free(memblock); 715 ::free(membase); 716 #endif 717 } 718 719 void os::init_random(long initval) { 720 _rand_seed = initval; 721 } 722 723 724 long os::random() { 725 /* standard, well-known linear congruential random generator with 726 * next_rand = (16807*seed) mod (2**31-1) 727 * see 728 * (1) "Random Number Generators: Good Ones Are Hard to Find", 729 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 730 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 731 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 732 */ 733 const long a = 16807; 734 const unsigned long m = 2147483647; 735 const long q = m / a; assert(q == 127773, "weird math"); 736 const long r = m % a; assert(r == 2836, "weird math"); 737 738 // compute az=2^31p+q 739 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 740 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 741 lo += (hi & 0x7FFF) << 16; 742 743 // if q overflowed, ignore the overflow and increment q 744 if (lo > m) { 745 lo &= m; 746 ++lo; 747 } 748 lo += hi >> 15; 749 750 // if (p+q) overflowed, ignore the overflow and increment (p+q) 751 if (lo > m) { 752 lo &= m; 753 ++lo; 754 } 755 return (_rand_seed = lo); 756 } 757 758 // The INITIALIZED state is distinguished from the SUSPENDED state because the 759 // conditions in which a thread is first started are different from those in which 760 // a suspension is resumed. These differences make it hard for us to apply the 761 // tougher checks when starting threads that we want to do when resuming them. 762 // However, when start_thread is called as a result of Thread.start, on a Java 763 // thread, the operation is synchronized on the Java Thread object. So there 764 // cannot be a race to start the thread and hence for the thread to exit while 765 // we are working on it. Non-Java threads that start Java threads either have 766 // to do so in a context in which races are impossible, or should do appropriate 767 // locking. 768 769 void os::start_thread(Thread* thread) { 770 // guard suspend/resume 771 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 772 OSThread* osthread = thread->osthread(); 773 osthread->set_state(RUNNABLE); 774 pd_start_thread(thread); 775 } 776 777 void os::abort(bool dump_core) { 778 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL); 779 } 780 781 //--------------------------------------------------------------------------- 782 // Helper functions for fatal error handler 783 784 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 785 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 786 787 int cols = 0; 788 int cols_per_line = 0; 789 switch (unitsize) { 790 case 1: cols_per_line = 16; break; 791 case 2: cols_per_line = 8; break; 792 case 4: cols_per_line = 4; break; 793 case 8: cols_per_line = 2; break; 794 default: return; 795 } 796 797 address p = start; 798 st->print(PTR_FORMAT ": ", p2i(start)); 799 while (p < end) { 800 switch (unitsize) { 801 case 1: st->print("%02x", *(u1*)p); break; 802 case 2: st->print("%04x", *(u2*)p); break; 803 case 4: st->print("%08x", *(u4*)p); break; 804 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 805 } 806 p += unitsize; 807 cols++; 808 if (cols >= cols_per_line && p < end) { 809 cols = 0; 810 st->cr(); 811 st->print(PTR_FORMAT ": ", p2i(p)); 812 } else { 813 st->print(" "); 814 } 815 } 816 st->cr(); 817 } 818 819 void os::print_environment_variables(outputStream* st, const char** env_list) { 820 if (env_list) { 821 st->print_cr("Environment Variables:"); 822 823 for (int i = 0; env_list[i] != NULL; i++) { 824 char *envvar = ::getenv(env_list[i]); 825 if (envvar != NULL) { 826 st->print("%s", env_list[i]); 827 st->print("="); 828 st->print_cr("%s", envvar); 829 } 830 } 831 } 832 } 833 834 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) { 835 // cpu 836 st->print("CPU:"); 837 st->print("total %d", os::processor_count()); 838 // It's not safe to query number of active processors after crash 839 // st->print("(active %d)", os::active_processor_count()); 840 st->print(" %s", VM_Version::cpu_features()); 841 st->cr(); 842 pd_print_cpu_info(st, buf, buflen); 843 } 844 845 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version 846 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) { 847 st->print("Host: "); 848 #ifndef PRODUCT 849 if (get_host_name(buf, buflen)) { 850 st->print("%s, ", buf); 851 } 852 #endif // PRODUCT 853 get_summary_cpu_info(buf, buflen); 854 st->print("%s, ", buf); 855 size_t mem = physical_memory()/G; 856 if (mem == 0) { // for low memory systems 857 mem = physical_memory()/M; 858 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem); 859 } else { 860 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem); 861 } 862 get_summary_os_info(buf, buflen); 863 st->print_raw(buf); 864 st->cr(); 865 } 866 867 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) { 868 const int secs_per_day = 86400; 869 const int secs_per_hour = 3600; 870 const int secs_per_min = 60; 871 872 time_t tloc; 873 (void)time(&tloc); 874 char* timestring = ctime(&tloc); // ctime adds newline. 875 // edit out the newline 876 char* nl = strchr(timestring, '\n'); 877 if (nl != NULL) { 878 *nl = '\0'; 879 } 880 881 struct tm tz; 882 if (localtime_pd(&tloc, &tz) != NULL) { 883 ::strftime(buf, buflen, "%Z", &tz); 884 st->print("Time: %s %s", timestring, buf); 885 } else { 886 st->print("Time: %s", timestring); 887 } 888 889 double t = os::elapsedTime(); 890 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 891 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 892 // before printf. We lost some precision, but who cares? 893 int eltime = (int)t; // elapsed time in seconds 894 895 // print elapsed time in a human-readable format: 896 int eldays = eltime / secs_per_day; 897 int day_secs = eldays * secs_per_day; 898 int elhours = (eltime - day_secs) / secs_per_hour; 899 int hour_secs = elhours * secs_per_hour; 900 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 901 int minute_secs = elmins * secs_per_min; 902 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 903 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 904 } 905 906 // moved from debug.cpp (used to be find()) but still called from there 907 // The verbose parameter is only set by the debug code in one case 908 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 909 address addr = (address)x; 910 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 911 if (b != NULL) { 912 if (b->is_buffer_blob()) { 913 // the interpreter is generated into a buffer blob 914 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 915 if (i != NULL) { 916 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin())); 917 i->print_on(st); 918 return; 919 } 920 if (Interpreter::contains(addr)) { 921 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 922 " (not bytecode specific)", p2i(addr)); 923 return; 924 } 925 // 926 if (AdapterHandlerLibrary::contains(b)) { 927 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin())); 928 AdapterHandlerLibrary::print_handler_on(st, b); 929 } 930 // the stubroutines are generated into a buffer blob 931 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 932 if (d != NULL) { 933 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin())); 934 d->print_on(st); 935 st->cr(); 936 return; 937 } 938 if (StubRoutines::contains(addr)) { 939 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr)); 940 return; 941 } 942 // the InlineCacheBuffer is using stubs generated into a buffer blob 943 if (InlineCacheBuffer::contains(addr)) { 944 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr)); 945 return; 946 } 947 VtableStub* v = VtableStubs::stub_containing(addr); 948 if (v != NULL) { 949 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point())); 950 v->print_on(st); 951 st->cr(); 952 return; 953 } 954 } 955 nmethod* nm = b->as_nmethod_or_null(); 956 if (nm != NULL) { 957 ResourceMark rm; 958 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 959 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm)); 960 if (verbose) { 961 st->print(" for "); 962 nm->method()->print_value_on(st); 963 } 964 st->cr(); 965 nm->print_nmethod(verbose); 966 return; 967 } 968 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin())); 969 b->print_on(st); 970 return; 971 } 972 973 if (Universe::heap()->is_in(addr)) { 974 HeapWord* p = Universe::heap()->block_start(addr); 975 bool print = false; 976 // If we couldn't find it it just may mean that heap wasn't parsable 977 // See if we were just given an oop directly 978 if (p != NULL && Universe::heap()->block_is_obj(p)) { 979 print = true; 980 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 981 p = (HeapWord*) addr; 982 print = true; 983 } 984 if (print) { 985 if (p == (HeapWord*) addr) { 986 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr)); 987 } else { 988 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p)); 989 } 990 oop(p)->print_on(st); 991 return; 992 } 993 } else { 994 if (Universe::heap()->is_in_reserved(addr)) { 995 st->print_cr(INTPTR_FORMAT " is an unallocated location " 996 "in the heap", p2i(addr)); 997 return; 998 } 999 } 1000 if (JNIHandles::is_global_handle((jobject) addr)) { 1001 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr)); 1002 return; 1003 } 1004 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 1005 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr)); 1006 return; 1007 } 1008 #ifndef PRODUCT 1009 // we don't keep the block list in product mode 1010 if (JNIHandleBlock::any_contains((jobject) addr)) { 1011 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr)); 1012 return; 1013 } 1014 #endif 1015 1016 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1017 // Check for privilege stack 1018 if (thread->privileged_stack_top() != NULL && 1019 thread->privileged_stack_top()->contains(addr)) { 1020 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1021 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread)); 1022 if (verbose) thread->print_on(st); 1023 return; 1024 } 1025 // If the addr is a java thread print information about that. 1026 if (addr == (address)thread) { 1027 if (verbose) { 1028 thread->print_on(st); 1029 } else { 1030 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr)); 1031 } 1032 return; 1033 } 1034 // If the addr is in the stack region for this thread then report that 1035 // and print thread info 1036 if (thread->stack_base() >= addr && 1037 addr > (thread->stack_base() - thread->stack_size())) { 1038 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1039 INTPTR_FORMAT, p2i(addr), p2i(thread)); 1040 if (verbose) thread->print_on(st); 1041 return; 1042 } 1043 1044 } 1045 1046 // Check if in metaspace and print types that have vptrs (only method now) 1047 if (Metaspace::contains(addr)) { 1048 if (Method::has_method_vptr((const void*)addr)) { 1049 ((Method*)addr)->print_value_on(st); 1050 st->cr(); 1051 } else { 1052 // Use addr->print() from the debugger instead (not here) 1053 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr)); 1054 } 1055 return; 1056 } 1057 1058 // Try an OS specific find 1059 if (os::find(addr, st)) { 1060 return; 1061 } 1062 1063 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr)); 1064 } 1065 1066 // Looks like all platforms except IA64 can use the same function to check 1067 // if C stack is walkable beyond current frame. The check for fp() is not 1068 // necessary on Sparc, but it's harmless. 1069 bool os::is_first_C_frame(frame* fr) { 1070 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32) 1071 // On IA64 we have to check if the callers bsp is still valid 1072 // (i.e. within the register stack bounds). 1073 // Notice: this only works for threads created by the VM and only if 1074 // we walk the current stack!!! If we want to be able to walk 1075 // arbitrary other threads, we'll have to somehow store the thread 1076 // object in the frame. 1077 Thread *thread = Thread::current(); 1078 if ((address)fr->fp() <= 1079 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1080 // This check is a little hacky, because on Linux the first C 1081 // frame's ('start_thread') register stack frame starts at 1082 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1083 // ('__pthread_bound_body') register stack frame seems to really 1084 // start at "register_stack_base". 1085 return true; 1086 } else { 1087 return false; 1088 } 1089 #elif defined(IA64) && defined(_WIN32) 1090 return true; 1091 #else 1092 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1093 // Check usp first, because if that's bad the other accessors may fault 1094 // on some architectures. Ditto ufp second, etc. 1095 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1096 // sp on amd can be 32 bit aligned. 1097 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1098 1099 uintptr_t usp = (uintptr_t)fr->sp(); 1100 if ((usp & sp_align_mask) != 0) return true; 1101 1102 uintptr_t ufp = (uintptr_t)fr->fp(); 1103 if ((ufp & fp_align_mask) != 0) return true; 1104 1105 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1106 if ((old_sp & sp_align_mask) != 0) return true; 1107 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1108 1109 uintptr_t old_fp = (uintptr_t)fr->link(); 1110 if ((old_fp & fp_align_mask) != 0) return true; 1111 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1112 1113 // stack grows downwards; if old_fp is below current fp or if the stack 1114 // frame is too large, either the stack is corrupted or fp is not saved 1115 // on stack (i.e. on x86, ebp may be used as general register). The stack 1116 // is not walkable beyond current frame. 1117 if (old_fp < ufp) return true; 1118 if (old_fp - ufp > 64 * K) return true; 1119 1120 return false; 1121 #endif 1122 } 1123 1124 #ifdef ASSERT 1125 extern "C" void test_random() { 1126 const double m = 2147483647; 1127 double mean = 0.0, variance = 0.0, t; 1128 long reps = 10000; 1129 unsigned long seed = 1; 1130 1131 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1132 os::init_random(seed); 1133 long num; 1134 for (int k = 0; k < reps; k++) { 1135 num = os::random(); 1136 double u = (double)num / m; 1137 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1138 1139 // calculate mean and variance of the random sequence 1140 mean += u; 1141 variance += (u*u); 1142 } 1143 mean /= reps; 1144 variance /= (reps - 1); 1145 1146 assert(num == 1043618065, "bad seed"); 1147 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1148 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1149 const double eps = 0.0001; 1150 t = fabsd(mean - 0.5018); 1151 assert(t < eps, "bad mean"); 1152 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1153 assert(t < eps, "bad variance"); 1154 } 1155 #endif 1156 1157 1158 // Set up the boot classpath. 1159 1160 char* os::format_boot_path(const char* format_string, 1161 const char* home, 1162 int home_len, 1163 char fileSep, 1164 char pathSep) { 1165 assert((fileSep == '/' && pathSep == ':') || 1166 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1167 1168 // Scan the format string to determine the length of the actual 1169 // boot classpath, and handle platform dependencies as well. 1170 int formatted_path_len = 0; 1171 const char* p; 1172 for (p = format_string; *p != 0; ++p) { 1173 if (*p == '%') formatted_path_len += home_len - 1; 1174 ++formatted_path_len; 1175 } 1176 1177 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1178 if (formatted_path == NULL) { 1179 return NULL; 1180 } 1181 1182 // Create boot classpath from format, substituting separator chars and 1183 // java home directory. 1184 char* q = formatted_path; 1185 for (p = format_string; *p != 0; ++p) { 1186 switch (*p) { 1187 case '%': 1188 strcpy(q, home); 1189 q += home_len; 1190 break; 1191 case '/': 1192 *q++ = fileSep; 1193 break; 1194 case ':': 1195 *q++ = pathSep; 1196 break; 1197 default: 1198 *q++ = *p; 1199 } 1200 } 1201 *q = '\0'; 1202 1203 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1204 return formatted_path; 1205 } 1206 1207 // returns a PATH of all entries in the given directory that do not start with a '.' 1208 static char* expand_entries_to_path(char* directory, char fileSep, char pathSep) { 1209 DIR* dir = os::opendir(directory); 1210 if (dir == NULL) return NULL; 1211 1212 char* path = NULL; 1213 size_t path_len = 0; // path length including \0 terminator 1214 1215 size_t directory_len = strlen(directory); 1216 struct dirent *entry; 1217 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal); 1218 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) { 1219 const char* name = entry->d_name; 1220 if (name[0] == '.') continue; 1221 1222 size_t name_len = strlen(name); 1223 size_t needed = directory_len + name_len + 2; 1224 size_t new_len = path_len + needed; 1225 if (path == NULL) { 1226 path = NEW_C_HEAP_ARRAY(char, new_len, mtInternal); 1227 } else { 1228 path = REALLOC_C_HEAP_ARRAY(char, path, new_len, mtInternal); 1229 } 1230 if (path == NULL) 1231 break; 1232 1233 // append <pathSep>directory<fileSep>name 1234 char* p = path; 1235 if (path_len > 0) { 1236 p += (path_len -1); 1237 *p = pathSep; 1238 p++; 1239 } 1240 1241 strcpy(p, directory); 1242 p += directory_len; 1243 1244 *p = fileSep; 1245 p++; 1246 1247 strcpy(p, name); 1248 p += name_len; 1249 1250 path_len = new_len; 1251 } 1252 1253 FREE_C_HEAP_ARRAY(char, dbuf); 1254 os::closedir(dir); 1255 1256 return path; 1257 } 1258 1259 bool os::set_boot_path(char fileSep, char pathSep) { 1260 const char* home = Arguments::get_java_home(); 1261 int home_len = (int)strlen(home); 1262 1263 char* sysclasspath = NULL; 1264 struct stat st; 1265 1266 // modular image if bootmodules.jimage exists 1267 char* jimage = format_boot_path("%/lib/modules/" BOOT_IMAGE_NAME, home, home_len, fileSep, pathSep); 1268 if (jimage == NULL) return false; 1269 bool has_jimage = (os::stat(jimage, &st) == 0); 1270 if (has_jimage) { 1271 Arguments::set_sysclasspath(jimage); 1272 FREE_C_HEAP_ARRAY(char, jimage); 1273 return true; 1274 } 1275 FREE_C_HEAP_ARRAY(char, jimage); 1276 1277 // check if developer build with exploded modules 1278 char* modules_dir = format_boot_path("%/modules", home, home_len, fileSep, pathSep); 1279 if (os::stat(modules_dir, &st) == 0) { 1280 if ((st.st_mode & S_IFDIR) == S_IFDIR) { 1281 sysclasspath = expand_entries_to_path(modules_dir, fileSep, pathSep); 1282 } 1283 } 1284 FREE_C_HEAP_ARRAY(char, modules_dir); 1285 1286 // fallback to classes 1287 if (sysclasspath == NULL) 1288 sysclasspath = format_boot_path("%/classes", home, home_len, fileSep, pathSep); 1289 1290 if (sysclasspath == NULL) return false; 1291 Arguments::set_sysclasspath(sysclasspath); 1292 FREE_C_HEAP_ARRAY(char, sysclasspath); 1293 1294 return true; 1295 } 1296 1297 /* 1298 * Splits a path, based on its separator, the number of 1299 * elements is returned back in n. 1300 * It is the callers responsibility to: 1301 * a> check the value of n, and n may be 0. 1302 * b> ignore any empty path elements 1303 * c> free up the data. 1304 */ 1305 char** os::split_path(const char* path, int* n) { 1306 *n = 0; 1307 if (path == NULL || strlen(path) == 0) { 1308 return NULL; 1309 } 1310 const char psepchar = *os::path_separator(); 1311 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1312 if (inpath == NULL) { 1313 return NULL; 1314 } 1315 strcpy(inpath, path); 1316 int count = 1; 1317 char* p = strchr(inpath, psepchar); 1318 // Get a count of elements to allocate memory 1319 while (p != NULL) { 1320 count++; 1321 p++; 1322 p = strchr(p, psepchar); 1323 } 1324 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1325 if (opath == NULL) { 1326 return NULL; 1327 } 1328 1329 // do the actual splitting 1330 p = inpath; 1331 for (int i = 0 ; i < count ; i++) { 1332 size_t len = strcspn(p, os::path_separator()); 1333 if (len > JVM_MAXPATHLEN) { 1334 return NULL; 1335 } 1336 // allocate the string and add terminator storage 1337 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1338 if (s == NULL) { 1339 return NULL; 1340 } 1341 strncpy(s, p, len); 1342 s[len] = '\0'; 1343 opath[i] = s; 1344 p += len + 1; 1345 } 1346 FREE_C_HEAP_ARRAY(char, inpath); 1347 *n = count; 1348 return opath; 1349 } 1350 1351 void os::set_memory_serialize_page(address page) { 1352 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1353 _mem_serialize_page = (volatile int32_t *)page; 1354 // We initialize the serialization page shift count here 1355 // We assume a cache line size of 64 bytes 1356 assert(SerializePageShiftCount == count, 1357 "thread size changed, fix SerializePageShiftCount constant"); 1358 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1359 } 1360 1361 static volatile intptr_t SerializePageLock = 0; 1362 1363 // This method is called from signal handler when SIGSEGV occurs while the current 1364 // thread tries to store to the "read-only" memory serialize page during state 1365 // transition. 1366 void os::block_on_serialize_page_trap() { 1367 log_debug(safepoint)("Block until the serialize page permission restored"); 1368 1369 // When VMThread is holding the SerializePageLock during modifying the 1370 // access permission of the memory serialize page, the following call 1371 // will block until the permission of that page is restored to rw. 1372 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1373 // this case, it's OK as the signal is synchronous and we know precisely when 1374 // it can occur. 1375 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1376 Thread::muxRelease(&SerializePageLock); 1377 } 1378 1379 // Serialize all thread state variables 1380 void os::serialize_thread_states() { 1381 // On some platforms such as Solaris & Linux, the time duration of the page 1382 // permission restoration is observed to be much longer than expected due to 1383 // scheduler starvation problem etc. To avoid the long synchronization 1384 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1385 // the mutator thread if such case is encountered. See bug 6546278 for details. 1386 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1387 os::protect_memory((char *)os::get_memory_serialize_page(), 1388 os::vm_page_size(), MEM_PROT_READ); 1389 os::protect_memory((char *)os::get_memory_serialize_page(), 1390 os::vm_page_size(), MEM_PROT_RW); 1391 Thread::muxRelease(&SerializePageLock); 1392 } 1393 1394 // Returns true if the current stack pointer is above the stack shadow 1395 // pages, false otherwise. 1396 1397 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method) { 1398 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1399 address sp = current_stack_pointer(); 1400 // Check if we have StackShadowPages above the yellow zone. This parameter 1401 // is dependent on the depth of the maximum VM call stack possible from 1402 // the handler for stack overflow. 'instanceof' in the stack overflow 1403 // handler or a println uses at least 8k stack of VM and native code 1404 // respectively. 1405 const int framesize_in_bytes = 1406 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1407 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1408 * vm_page_size()) + framesize_in_bytes; 1409 // The very lower end of the stack 1410 address stack_limit = thread->stack_base() - thread->stack_size(); 1411 return (sp > (stack_limit + reserved_area)); 1412 } 1413 1414 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1415 assert(min_pages > 0, "sanity"); 1416 if (UseLargePages) { 1417 const size_t max_page_size = region_size / min_pages; 1418 1419 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1420 const size_t page_size = _page_sizes[i]; 1421 if (page_size <= max_page_size) { 1422 if (!must_be_aligned || is_size_aligned(region_size, page_size)) { 1423 return page_size; 1424 } 1425 } 1426 } 1427 } 1428 1429 return vm_page_size(); 1430 } 1431 1432 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1433 return page_size_for_region(region_size, min_pages, true); 1434 } 1435 1436 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1437 return page_size_for_region(region_size, min_pages, false); 1438 } 1439 1440 #ifndef PRODUCT 1441 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1442 { 1443 if (TracePageSizes) { 1444 tty->print("%s: ", str); 1445 for (int i = 0; i < count; ++i) { 1446 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1447 } 1448 tty->cr(); 1449 } 1450 } 1451 1452 void os::trace_page_sizes(const char* str, const size_t region_min_size, 1453 const size_t region_max_size, const size_t page_size, 1454 const char* base, const size_t size) 1455 { 1456 if (TracePageSizes) { 1457 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1458 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1459 " size=" SIZE_FORMAT, 1460 str, region_min_size, region_max_size, 1461 page_size, p2i(base), size); 1462 } 1463 } 1464 #endif // #ifndef PRODUCT 1465 1466 // This is the working definition of a server class machine: 1467 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1468 // because the graphics memory (?) sometimes masks physical memory. 1469 // If you want to change the definition of a server class machine 1470 // on some OS or platform, e.g., >=4GB on Windows platforms, 1471 // then you'll have to parameterize this method based on that state, 1472 // as was done for logical processors here, or replicate and 1473 // specialize this method for each platform. (Or fix os to have 1474 // some inheritance structure and use subclassing. Sigh.) 1475 // If you want some platform to always or never behave as a server 1476 // class machine, change the setting of AlwaysActAsServerClassMachine 1477 // and NeverActAsServerClassMachine in globals*.hpp. 1478 bool os::is_server_class_machine() { 1479 // First check for the early returns 1480 if (NeverActAsServerClassMachine) { 1481 return false; 1482 } 1483 if (AlwaysActAsServerClassMachine) { 1484 return true; 1485 } 1486 // Then actually look at the machine 1487 bool result = false; 1488 const unsigned int server_processors = 2; 1489 const julong server_memory = 2UL * G; 1490 // We seem not to get our full complement of memory. 1491 // We allow some part (1/8?) of the memory to be "missing", 1492 // based on the sizes of DIMMs, and maybe graphics cards. 1493 const julong missing_memory = 256UL * M; 1494 1495 /* Is this a server class machine? */ 1496 if ((os::active_processor_count() >= (int)server_processors) && 1497 (os::physical_memory() >= (server_memory - missing_memory))) { 1498 const unsigned int logical_processors = 1499 VM_Version::logical_processors_per_package(); 1500 if (logical_processors > 1) { 1501 const unsigned int physical_packages = 1502 os::active_processor_count() / logical_processors; 1503 if (physical_packages > server_processors) { 1504 result = true; 1505 } 1506 } else { 1507 result = true; 1508 } 1509 } 1510 return result; 1511 } 1512 1513 void os::SuspendedThreadTask::run() { 1514 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1515 internal_do_task(); 1516 _done = true; 1517 } 1518 1519 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1520 return os::pd_create_stack_guard_pages(addr, bytes); 1521 } 1522 1523 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1524 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1525 if (result != NULL) { 1526 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1527 } 1528 1529 return result; 1530 } 1531 1532 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1533 MEMFLAGS flags) { 1534 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1535 if (result != NULL) { 1536 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1537 MemTracker::record_virtual_memory_type((address)result, flags); 1538 } 1539 1540 return result; 1541 } 1542 1543 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1544 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1545 if (result != NULL) { 1546 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1547 } 1548 return result; 1549 } 1550 1551 void os::split_reserved_memory(char *base, size_t size, 1552 size_t split, bool realloc) { 1553 pd_split_reserved_memory(base, size, split, realloc); 1554 } 1555 1556 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1557 bool res = pd_commit_memory(addr, bytes, executable); 1558 if (res) { 1559 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1560 } 1561 return res; 1562 } 1563 1564 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1565 bool executable) { 1566 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1567 if (res) { 1568 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1569 } 1570 return res; 1571 } 1572 1573 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1574 const char* mesg) { 1575 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1576 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1577 } 1578 1579 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1580 bool executable, const char* mesg) { 1581 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1582 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1583 } 1584 1585 bool os::uncommit_memory(char* addr, size_t bytes) { 1586 bool res; 1587 if (MemTracker::tracking_level() > NMT_minimal) { 1588 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1589 res = pd_uncommit_memory(addr, bytes); 1590 if (res) { 1591 tkr.record((address)addr, bytes); 1592 } 1593 } else { 1594 res = pd_uncommit_memory(addr, bytes); 1595 } 1596 return res; 1597 } 1598 1599 bool os::release_memory(char* addr, size_t bytes) { 1600 bool res; 1601 if (MemTracker::tracking_level() > NMT_minimal) { 1602 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1603 res = pd_release_memory(addr, bytes); 1604 if (res) { 1605 tkr.record((address)addr, bytes); 1606 } 1607 } else { 1608 res = pd_release_memory(addr, bytes); 1609 } 1610 return res; 1611 } 1612 1613 void os::pretouch_memory(char* start, char* end) { 1614 for (volatile char *p = start; p < end; p += os::vm_page_size()) { 1615 *p = 0; 1616 } 1617 } 1618 1619 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1620 char *addr, size_t bytes, bool read_only, 1621 bool allow_exec) { 1622 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1623 if (result != NULL) { 1624 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1625 } 1626 return result; 1627 } 1628 1629 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1630 char *addr, size_t bytes, bool read_only, 1631 bool allow_exec) { 1632 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1633 read_only, allow_exec); 1634 } 1635 1636 bool os::unmap_memory(char *addr, size_t bytes) { 1637 bool result; 1638 if (MemTracker::tracking_level() > NMT_minimal) { 1639 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1640 result = pd_unmap_memory(addr, bytes); 1641 if (result) { 1642 tkr.record((address)addr, bytes); 1643 } 1644 } else { 1645 result = pd_unmap_memory(addr, bytes); 1646 } 1647 return result; 1648 } 1649 1650 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1651 pd_free_memory(addr, bytes, alignment_hint); 1652 } 1653 1654 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1655 pd_realign_memory(addr, bytes, alignment_hint); 1656 } 1657 1658 #ifndef TARGET_OS_FAMILY_windows 1659 /* try to switch state from state "from" to state "to" 1660 * returns the state set after the method is complete 1661 */ 1662 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1663 os::SuspendResume::State to) 1664 { 1665 os::SuspendResume::State result = 1666 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1667 if (result == from) { 1668 // success 1669 return to; 1670 } 1671 return result; 1672 } 1673 #endif 1674 1675 /////////////// Unit tests /////////////// 1676 1677 #ifndef PRODUCT 1678 1679 #define assert_eq(a,b) assert(a == b, SIZE_FORMAT " != " SIZE_FORMAT, a, b) 1680 1681 class TestOS : AllStatic { 1682 static size_t small_page_size() { 1683 return os::vm_page_size(); 1684 } 1685 1686 static size_t large_page_size() { 1687 const size_t large_page_size_example = 4 * M; 1688 return os::page_size_for_region_aligned(large_page_size_example, 1); 1689 } 1690 1691 static void test_page_size_for_region_aligned() { 1692 if (UseLargePages) { 1693 const size_t small_page = small_page_size(); 1694 const size_t large_page = large_page_size(); 1695 1696 if (large_page > small_page) { 1697 size_t num_small_pages_in_large = large_page / small_page; 1698 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large); 1699 1700 assert_eq(page, small_page); 1701 } 1702 } 1703 } 1704 1705 static void test_page_size_for_region_alignment() { 1706 if (UseLargePages) { 1707 const size_t small_page = small_page_size(); 1708 const size_t large_page = large_page_size(); 1709 if (large_page > small_page) { 1710 const size_t unaligned_region = large_page + 17; 1711 size_t page = os::page_size_for_region_aligned(unaligned_region, 1); 1712 assert_eq(page, small_page); 1713 1714 const size_t num_pages = 5; 1715 const size_t aligned_region = large_page * num_pages; 1716 page = os::page_size_for_region_aligned(aligned_region, num_pages); 1717 assert_eq(page, large_page); 1718 } 1719 } 1720 } 1721 1722 static void test_page_size_for_region_unaligned() { 1723 if (UseLargePages) { 1724 // Given exact page size, should return that page size. 1725 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1726 size_t expected = os::_page_sizes[i]; 1727 size_t actual = os::page_size_for_region_unaligned(expected, 1); 1728 assert_eq(expected, actual); 1729 } 1730 1731 // Given slightly larger size than a page size, return the page size. 1732 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1733 size_t expected = os::_page_sizes[i]; 1734 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1); 1735 assert_eq(expected, actual); 1736 } 1737 1738 // Given a slightly smaller size than a page size, 1739 // return the next smaller page size. 1740 if (os::_page_sizes[1] > os::_page_sizes[0]) { 1741 size_t expected = os::_page_sizes[0]; 1742 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1); 1743 assert_eq(actual, expected); 1744 } 1745 1746 // Return small page size for values less than a small page. 1747 size_t small_page = small_page_size(); 1748 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1); 1749 assert_eq(small_page, actual); 1750 } 1751 } 1752 1753 public: 1754 static void run_tests() { 1755 test_page_size_for_region_aligned(); 1756 test_page_size_for_region_alignment(); 1757 test_page_size_for_region_unaligned(); 1758 } 1759 }; 1760 1761 void TestOS_test() { 1762 TestOS::run_tests(); 1763 } 1764 1765 #endif // PRODUCT