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(gclog_or_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 VM_Version::vm_init_before_ergo(); 320 } 321 322 void os::signal_init() { 323 if (!ReduceSignalUsage) { 324 // Setup JavaThread for processing signals 325 EXCEPTION_MARK; 326 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 327 instanceKlassHandle klass (THREAD, k); 328 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 329 330 const char thread_name[] = "Signal Dispatcher"; 331 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 332 333 // Initialize thread_oop to put it into the system threadGroup 334 Handle thread_group (THREAD, Universe::system_thread_group()); 335 JavaValue result(T_VOID); 336 JavaCalls::call_special(&result, thread_oop, 337 klass, 338 vmSymbols::object_initializer_name(), 339 vmSymbols::threadgroup_string_void_signature(), 340 thread_group, 341 string, 342 CHECK); 343 344 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 345 JavaCalls::call_special(&result, 346 thread_group, 347 group, 348 vmSymbols::add_method_name(), 349 vmSymbols::thread_void_signature(), 350 thread_oop, // ARG 1 351 CHECK); 352 353 os::signal_init_pd(); 354 355 { MutexLocker mu(Threads_lock); 356 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 357 358 // At this point it may be possible that no osthread was created for the 359 // JavaThread due to lack of memory. We would have to throw an exception 360 // in that case. However, since this must work and we do not allow 361 // exceptions anyway, check and abort if this fails. 362 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 363 vm_exit_during_initialization("java.lang.OutOfMemoryError", 364 os::native_thread_creation_failed_msg()); 365 } 366 367 java_lang_Thread::set_thread(thread_oop(), signal_thread); 368 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 369 java_lang_Thread::set_daemon(thread_oop()); 370 371 signal_thread->set_threadObj(thread_oop()); 372 Threads::add(signal_thread); 373 Thread::start(signal_thread); 374 } 375 // Handle ^BREAK 376 os::signal(SIGBREAK, os::user_handler()); 377 } 378 } 379 380 381 void os::terminate_signal_thread() { 382 if (!ReduceSignalUsage) 383 signal_notify(sigexitnum_pd()); 384 } 385 386 387 // --------------------- loading libraries --------------------- 388 389 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 390 extern struct JavaVM_ main_vm; 391 392 static void* _native_java_library = NULL; 393 394 void* os::native_java_library() { 395 if (_native_java_library == NULL) { 396 char buffer[JVM_MAXPATHLEN]; 397 char ebuf[1024]; 398 399 // Try to load verify dll first. In 1.3 java dll depends on it and is not 400 // always able to find it when the loading executable is outside the JDK. 401 // In order to keep working with 1.2 we ignore any loading errors. 402 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 403 "verify")) { 404 dll_load(buffer, ebuf, sizeof(ebuf)); 405 } 406 407 // Load java dll 408 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 409 "java")) { 410 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 411 } 412 if (_native_java_library == NULL) { 413 vm_exit_during_initialization("Unable to load native library", ebuf); 414 } 415 416 #if defined(__OpenBSD__) 417 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 418 // ignore errors 419 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 420 "net")) { 421 dll_load(buffer, ebuf, sizeof(ebuf)); 422 } 423 #endif 424 } 425 static jboolean onLoaded = JNI_FALSE; 426 if (onLoaded) { 427 // We may have to wait to fire OnLoad until TLS is initialized. 428 if (ThreadLocalStorage::is_initialized()) { 429 // The JNI_OnLoad handling is normally done by method load in 430 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 431 // explicitly so we have to check for JNI_OnLoad as well 432 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 433 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 434 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 435 if (JNI_OnLoad != NULL) { 436 JavaThread* thread = JavaThread::current(); 437 ThreadToNativeFromVM ttn(thread); 438 HandleMark hm(thread); 439 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 440 onLoaded = JNI_TRUE; 441 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 442 vm_exit_during_initialization("Unsupported JNI version"); 443 } 444 } 445 } 446 } 447 return _native_java_library; 448 } 449 450 /* 451 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 452 * If check_lib == true then we are looking for an 453 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 454 * this library is statically linked into the image. 455 * If check_lib == false then we will look for the appropriate symbol in the 456 * executable if agent_lib->is_static_lib() == true or in the shared library 457 * referenced by 'handle'. 458 */ 459 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 460 const char *syms[], size_t syms_len) { 461 assert(agent_lib != NULL, "sanity check"); 462 const char *lib_name; 463 void *handle = agent_lib->os_lib(); 464 void *entryName = NULL; 465 char *agent_function_name; 466 size_t i; 467 468 // If checking then use the agent name otherwise test is_static_lib() to 469 // see how to process this lookup 470 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 471 for (i = 0; i < syms_len; i++) { 472 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 473 if (agent_function_name == NULL) { 474 break; 475 } 476 entryName = dll_lookup(handle, agent_function_name); 477 FREE_C_HEAP_ARRAY(char, agent_function_name); 478 if (entryName != NULL) { 479 break; 480 } 481 } 482 return entryName; 483 } 484 485 // See if the passed in agent is statically linked into the VM image. 486 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 487 size_t syms_len) { 488 void *ret; 489 void *proc_handle; 490 void *save_handle; 491 492 assert(agent_lib != NULL, "sanity check"); 493 if (agent_lib->name() == NULL) { 494 return false; 495 } 496 proc_handle = get_default_process_handle(); 497 // Check for Agent_OnLoad/Attach_lib_name function 498 save_handle = agent_lib->os_lib(); 499 // We want to look in this process' symbol table. 500 agent_lib->set_os_lib(proc_handle); 501 ret = find_agent_function(agent_lib, true, syms, syms_len); 502 if (ret != NULL) { 503 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 504 agent_lib->set_valid(); 505 agent_lib->set_static_lib(true); 506 return true; 507 } 508 agent_lib->set_os_lib(save_handle); 509 return false; 510 } 511 512 // --------------------- heap allocation utilities --------------------- 513 514 char *os::strdup(const char *str, MEMFLAGS flags) { 515 size_t size = strlen(str); 516 char *dup_str = (char *)malloc(size + 1, flags); 517 if (dup_str == NULL) return NULL; 518 strcpy(dup_str, str); 519 return dup_str; 520 } 521 522 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) { 523 char* p = os::strdup(str, flags); 524 if (p == NULL) { 525 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom"); 526 } 527 return p; 528 } 529 530 531 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 532 533 #ifdef ASSERT 534 535 static void verify_memory(void* ptr) { 536 GuardedMemory guarded(ptr); 537 if (!guarded.verify_guards()) { 538 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 539 tty->print_cr("## memory stomp:"); 540 guarded.print_on(tty); 541 fatal("memory stomping error"); 542 } 543 } 544 545 #endif 546 547 // 548 // This function supports testing of the malloc out of memory 549 // condition without really running the system out of memory. 550 // 551 static bool has_reached_max_malloc_test_peak(size_t alloc_size) { 552 if (MallocMaxTestWords > 0) { 553 jint words = (jint)(alloc_size / BytesPerWord); 554 555 if ((cur_malloc_words + words) > MallocMaxTestWords) { 556 return true; 557 } 558 Atomic::add(words, (volatile jint *)&cur_malloc_words); 559 } 560 return false; 561 } 562 563 void* os::malloc(size_t size, MEMFLAGS flags) { 564 return os::malloc(size, flags, CALLER_PC); 565 } 566 567 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 568 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 569 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 570 571 #ifdef ASSERT 572 // checking for the WatcherThread and crash_protection first 573 // since os::malloc can be called when the libjvm.{dll,so} is 574 // first loaded and we don't have a thread yet. 575 // try to find the thread after we see that the watcher thread 576 // exists and has crash protection. 577 WatcherThread *wt = WatcherThread::watcher_thread(); 578 if (wt != NULL && wt->has_crash_protection()) { 579 Thread* thread = ThreadLocalStorage::get_thread_slow(); 580 if (thread == wt) { 581 assert(!wt->has_crash_protection(), 582 "Can't malloc with crash protection from WatcherThread"); 583 } 584 } 585 #endif 586 587 if (size == 0) { 588 // return a valid pointer if size is zero 589 // if NULL is returned the calling functions assume out of memory. 590 size = 1; 591 } 592 593 // NMT support 594 NMT_TrackingLevel level = MemTracker::tracking_level(); 595 size_t nmt_header_size = MemTracker::malloc_header_size(level); 596 597 #ifndef ASSERT 598 const size_t alloc_size = size + nmt_header_size; 599 #else 600 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size); 601 if (size + nmt_header_size > alloc_size) { // Check for rollover. 602 return NULL; 603 } 604 #endif 605 606 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 607 608 // For the test flag -XX:MallocMaxTestWords 609 if (has_reached_max_malloc_test_peak(size)) { 610 return NULL; 611 } 612 613 u_char* ptr; 614 ptr = (u_char*)::malloc(alloc_size); 615 616 #ifdef ASSERT 617 if (ptr == NULL) { 618 return NULL; 619 } 620 // Wrap memory with guard 621 GuardedMemory guarded(ptr, size + nmt_header_size); 622 ptr = guarded.get_user_ptr(); 623 #endif 624 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 625 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 626 breakpoint(); 627 } 628 debug_only(if (paranoid) verify_memory(ptr)); 629 if (PrintMalloc && tty != NULL) { 630 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 631 } 632 633 // we do not track guard memory 634 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level); 635 } 636 637 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 638 return os::realloc(memblock, size, flags, CALLER_PC); 639 } 640 641 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 642 643 // For the test flag -XX:MallocMaxTestWords 644 if (has_reached_max_malloc_test_peak(size)) { 645 return NULL; 646 } 647 648 #ifndef ASSERT 649 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 650 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 651 // NMT support 652 void* membase = MemTracker::record_free(memblock); 653 NMT_TrackingLevel level = MemTracker::tracking_level(); 654 size_t nmt_header_size = MemTracker::malloc_header_size(level); 655 void* ptr = ::realloc(membase, size + nmt_header_size); 656 return MemTracker::record_malloc(ptr, size, memflags, stack, level); 657 #else 658 if (memblock == NULL) { 659 return os::malloc(size, memflags, stack); 660 } 661 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 662 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock)); 663 breakpoint(); 664 } 665 // NMT support 666 void* membase = MemTracker::malloc_base(memblock); 667 verify_memory(membase); 668 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 669 if (size == 0) { 670 return NULL; 671 } 672 // always move the block 673 void* ptr = os::malloc(size, memflags, stack); 674 if (PrintMalloc && tty != NULL) { 675 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr)); 676 } 677 // Copy to new memory if malloc didn't fail 678 if ( ptr != NULL ) { 679 GuardedMemory guarded(MemTracker::malloc_base(memblock)); 680 // Guard's user data contains NMT header 681 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock); 682 memcpy(ptr, memblock, MIN2(size, memblock_size)); 683 if (paranoid) verify_memory(MemTracker::malloc_base(ptr)); 684 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 685 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 686 breakpoint(); 687 } 688 os::free(memblock); 689 } 690 return ptr; 691 #endif 692 } 693 694 695 void os::free(void *memblock) { 696 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 697 #ifdef ASSERT 698 if (memblock == NULL) return; 699 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 700 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock)); 701 breakpoint(); 702 } 703 void* membase = MemTracker::record_free(memblock); 704 verify_memory(membase); 705 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 706 707 GuardedMemory guarded(membase); 708 size_t size = guarded.get_user_size(); 709 inc_stat_counter(&free_bytes, size); 710 membase = guarded.release_for_freeing(); 711 if (PrintMalloc && tty != NULL) { 712 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase); 713 } 714 ::free(membase); 715 #else 716 void* membase = MemTracker::record_free(memblock); 717 ::free(membase); 718 #endif 719 } 720 721 void os::init_random(long initval) { 722 _rand_seed = initval; 723 } 724 725 726 long os::random() { 727 /* standard, well-known linear congruential random generator with 728 * next_rand = (16807*seed) mod (2**31-1) 729 * see 730 * (1) "Random Number Generators: Good Ones Are Hard to Find", 731 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 732 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 733 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 734 */ 735 const long a = 16807; 736 const unsigned long m = 2147483647; 737 const long q = m / a; assert(q == 127773, "weird math"); 738 const long r = m % a; assert(r == 2836, "weird math"); 739 740 // compute az=2^31p+q 741 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 742 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 743 lo += (hi & 0x7FFF) << 16; 744 745 // if q overflowed, ignore the overflow and increment q 746 if (lo > m) { 747 lo &= m; 748 ++lo; 749 } 750 lo += hi >> 15; 751 752 // if (p+q) overflowed, ignore the overflow and increment (p+q) 753 if (lo > m) { 754 lo &= m; 755 ++lo; 756 } 757 return (_rand_seed = lo); 758 } 759 760 // The INITIALIZED state is distinguished from the SUSPENDED state because the 761 // conditions in which a thread is first started are different from those in which 762 // a suspension is resumed. These differences make it hard for us to apply the 763 // tougher checks when starting threads that we want to do when resuming them. 764 // However, when start_thread is called as a result of Thread.start, on a Java 765 // thread, the operation is synchronized on the Java Thread object. So there 766 // cannot be a race to start the thread and hence for the thread to exit while 767 // we are working on it. Non-Java threads that start Java threads either have 768 // to do so in a context in which races are impossible, or should do appropriate 769 // locking. 770 771 void os::start_thread(Thread* thread) { 772 // guard suspend/resume 773 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 774 OSThread* osthread = thread->osthread(); 775 osthread->set_state(RUNNABLE); 776 pd_start_thread(thread); 777 } 778 779 void os::abort(bool dump_core) { 780 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL); 781 } 782 783 //--------------------------------------------------------------------------- 784 // Helper functions for fatal error handler 785 786 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 787 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 788 789 int cols = 0; 790 int cols_per_line = 0; 791 switch (unitsize) { 792 case 1: cols_per_line = 16; break; 793 case 2: cols_per_line = 8; break; 794 case 4: cols_per_line = 4; break; 795 case 8: cols_per_line = 2; break; 796 default: return; 797 } 798 799 address p = start; 800 st->print(PTR_FORMAT ": ", p2i(start)); 801 while (p < end) { 802 switch (unitsize) { 803 case 1: st->print("%02x", *(u1*)p); break; 804 case 2: st->print("%04x", *(u2*)p); break; 805 case 4: st->print("%08x", *(u4*)p); break; 806 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 807 } 808 p += unitsize; 809 cols++; 810 if (cols >= cols_per_line && p < end) { 811 cols = 0; 812 st->cr(); 813 st->print(PTR_FORMAT ": ", p2i(p)); 814 } else { 815 st->print(" "); 816 } 817 } 818 st->cr(); 819 } 820 821 void os::print_environment_variables(outputStream* st, const char** env_list) { 822 if (env_list) { 823 st->print_cr("Environment Variables:"); 824 825 for (int i = 0; env_list[i] != NULL; i++) { 826 char *envvar = ::getenv(env_list[i]); 827 if (envvar != NULL) { 828 st->print("%s", env_list[i]); 829 st->print("="); 830 st->print_cr("%s", envvar); 831 } 832 } 833 } 834 } 835 836 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) { 837 // cpu 838 st->print("CPU:"); 839 st->print("total %d", os::processor_count()); 840 // It's not safe to query number of active processors after crash 841 // st->print("(active %d)", os::active_processor_count()); 842 st->print(" %s", VM_Version::cpu_features()); 843 st->cr(); 844 pd_print_cpu_info(st, buf, buflen); 845 } 846 847 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version 848 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) { 849 st->print("Host: "); 850 #ifndef PRODUCT 851 if (get_host_name(buf, buflen)) { 852 st->print("%s, ", buf); 853 } 854 #endif // PRODUCT 855 get_summary_cpu_info(buf, buflen); 856 st->print("%s, ", buf); 857 size_t mem = physical_memory()/G; 858 if (mem == 0) { // for low memory systems 859 mem = physical_memory()/M; 860 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem); 861 } else { 862 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem); 863 } 864 get_summary_os_info(buf, buflen); 865 st->print_raw(buf); 866 st->cr(); 867 } 868 869 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) { 870 const int secs_per_day = 86400; 871 const int secs_per_hour = 3600; 872 const int secs_per_min = 60; 873 874 time_t tloc; 875 (void)time(&tloc); 876 char* timestring = ctime(&tloc); // ctime adds newline. 877 // edit out the newline 878 char* nl = strchr(timestring, '\n'); 879 if (nl != NULL) { 880 *nl = '\0'; 881 } 882 883 struct tm tz; 884 if (localtime_pd(&tloc, &tz) != NULL) { 885 ::strftime(buf, buflen, "%Z", &tz); 886 st->print("Time: %s %s", timestring, buf); 887 } else { 888 st->print("Time: %s", timestring); 889 } 890 891 double t = os::elapsedTime(); 892 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 893 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 894 // before printf. We lost some precision, but who cares? 895 int eltime = (int)t; // elapsed time in seconds 896 897 // print elapsed time in a human-readable format: 898 int eldays = eltime / secs_per_day; 899 int day_secs = eldays * secs_per_day; 900 int elhours = (eltime - day_secs) / secs_per_hour; 901 int hour_secs = elhours * secs_per_hour; 902 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 903 int minute_secs = elmins * secs_per_min; 904 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 905 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 906 } 907 908 // moved from debug.cpp (used to be find()) but still called from there 909 // The verbose parameter is only set by the debug code in one case 910 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 911 address addr = (address)x; 912 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 913 if (b != NULL) { 914 if (b->is_buffer_blob()) { 915 // the interpreter is generated into a buffer blob 916 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 917 if (i != NULL) { 918 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin())); 919 i->print_on(st); 920 return; 921 } 922 if (Interpreter::contains(addr)) { 923 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 924 " (not bytecode specific)", p2i(addr)); 925 return; 926 } 927 // 928 if (AdapterHandlerLibrary::contains(b)) { 929 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin())); 930 AdapterHandlerLibrary::print_handler_on(st, b); 931 } 932 // the stubroutines are generated into a buffer blob 933 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 934 if (d != NULL) { 935 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin())); 936 d->print_on(st); 937 st->cr(); 938 return; 939 } 940 if (StubRoutines::contains(addr)) { 941 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr)); 942 return; 943 } 944 // the InlineCacheBuffer is using stubs generated into a buffer blob 945 if (InlineCacheBuffer::contains(addr)) { 946 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr)); 947 return; 948 } 949 VtableStub* v = VtableStubs::stub_containing(addr); 950 if (v != NULL) { 951 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point())); 952 v->print_on(st); 953 st->cr(); 954 return; 955 } 956 } 957 nmethod* nm = b->as_nmethod_or_null(); 958 if (nm != NULL) { 959 ResourceMark rm; 960 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 961 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm)); 962 if (verbose) { 963 st->print(" for "); 964 nm->method()->print_value_on(st); 965 } 966 st->cr(); 967 nm->print_nmethod(verbose); 968 return; 969 } 970 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin())); 971 b->print_on(st); 972 return; 973 } 974 975 if (Universe::heap()->is_in(addr)) { 976 HeapWord* p = Universe::heap()->block_start(addr); 977 bool print = false; 978 // If we couldn't find it it just may mean that heap wasn't parsable 979 // See if we were just given an oop directly 980 if (p != NULL && Universe::heap()->block_is_obj(p)) { 981 print = true; 982 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 983 p = (HeapWord*) addr; 984 print = true; 985 } 986 if (print) { 987 if (p == (HeapWord*) addr) { 988 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr)); 989 } else { 990 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p)); 991 } 992 oop(p)->print_on(st); 993 return; 994 } 995 } else { 996 if (Universe::heap()->is_in_reserved(addr)) { 997 st->print_cr(INTPTR_FORMAT " is an unallocated location " 998 "in the heap", p2i(addr)); 999 return; 1000 } 1001 } 1002 if (JNIHandles::is_global_handle((jobject) addr)) { 1003 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr)); 1004 return; 1005 } 1006 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 1007 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr)); 1008 return; 1009 } 1010 #ifndef PRODUCT 1011 // we don't keep the block list in product mode 1012 if (JNIHandleBlock::any_contains((jobject) addr)) { 1013 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr)); 1014 return; 1015 } 1016 #endif 1017 1018 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1019 // Check for privilege stack 1020 if (thread->privileged_stack_top() != NULL && 1021 thread->privileged_stack_top()->contains(addr)) { 1022 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1023 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread)); 1024 if (verbose) thread->print_on(st); 1025 return; 1026 } 1027 // If the addr is a java thread print information about that. 1028 if (addr == (address)thread) { 1029 if (verbose) { 1030 thread->print_on(st); 1031 } else { 1032 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr)); 1033 } 1034 return; 1035 } 1036 // If the addr is in the stack region for this thread then report that 1037 // and print thread info 1038 if (thread->stack_base() >= addr && 1039 addr > (thread->stack_base() - thread->stack_size())) { 1040 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1041 INTPTR_FORMAT, p2i(addr), p2i(thread)); 1042 if (verbose) thread->print_on(st); 1043 return; 1044 } 1045 1046 } 1047 1048 // Check if in metaspace and print types that have vptrs (only method now) 1049 if (Metaspace::contains(addr)) { 1050 if (Method::has_method_vptr((const void*)addr)) { 1051 ((Method*)addr)->print_value_on(st); 1052 st->cr(); 1053 } else { 1054 // Use addr->print() from the debugger instead (not here) 1055 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr)); 1056 } 1057 return; 1058 } 1059 1060 // Try an OS specific find 1061 if (os::find(addr, st)) { 1062 return; 1063 } 1064 1065 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr)); 1066 } 1067 1068 // Looks like all platforms except IA64 can use the same function to check 1069 // if C stack is walkable beyond current frame. The check for fp() is not 1070 // necessary on Sparc, but it's harmless. 1071 bool os::is_first_C_frame(frame* fr) { 1072 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32) 1073 // On IA64 we have to check if the callers bsp is still valid 1074 // (i.e. within the register stack bounds). 1075 // Notice: this only works for threads created by the VM and only if 1076 // we walk the current stack!!! If we want to be able to walk 1077 // arbitrary other threads, we'll have to somehow store the thread 1078 // object in the frame. 1079 Thread *thread = Thread::current(); 1080 if ((address)fr->fp() <= 1081 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1082 // This check is a little hacky, because on Linux the first C 1083 // frame's ('start_thread') register stack frame starts at 1084 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1085 // ('__pthread_bound_body') register stack frame seems to really 1086 // start at "register_stack_base". 1087 return true; 1088 } else { 1089 return false; 1090 } 1091 #elif defined(IA64) && defined(_WIN32) 1092 return true; 1093 #else 1094 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1095 // Check usp first, because if that's bad the other accessors may fault 1096 // on some architectures. Ditto ufp second, etc. 1097 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1098 // sp on amd can be 32 bit aligned. 1099 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1100 1101 uintptr_t usp = (uintptr_t)fr->sp(); 1102 if ((usp & sp_align_mask) != 0) return true; 1103 1104 uintptr_t ufp = (uintptr_t)fr->fp(); 1105 if ((ufp & fp_align_mask) != 0) return true; 1106 1107 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1108 if ((old_sp & sp_align_mask) != 0) return true; 1109 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1110 1111 uintptr_t old_fp = (uintptr_t)fr->link(); 1112 if ((old_fp & fp_align_mask) != 0) return true; 1113 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1114 1115 // stack grows downwards; if old_fp is below current fp or if the stack 1116 // frame is too large, either the stack is corrupted or fp is not saved 1117 // on stack (i.e. on x86, ebp may be used as general register). The stack 1118 // is not walkable beyond current frame. 1119 if (old_fp < ufp) return true; 1120 if (old_fp - ufp > 64 * K) return true; 1121 1122 return false; 1123 #endif 1124 } 1125 1126 #ifdef ASSERT 1127 extern "C" void test_random() { 1128 const double m = 2147483647; 1129 double mean = 0.0, variance = 0.0, t; 1130 long reps = 10000; 1131 unsigned long seed = 1; 1132 1133 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1134 os::init_random(seed); 1135 long num; 1136 for (int k = 0; k < reps; k++) { 1137 num = os::random(); 1138 double u = (double)num / m; 1139 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1140 1141 // calculate mean and variance of the random sequence 1142 mean += u; 1143 variance += (u*u); 1144 } 1145 mean /= reps; 1146 variance /= (reps - 1); 1147 1148 assert(num == 1043618065, "bad seed"); 1149 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1150 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1151 const double eps = 0.0001; 1152 t = fabsd(mean - 0.5018); 1153 assert(t < eps, "bad mean"); 1154 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1155 assert(t < eps, "bad variance"); 1156 } 1157 #endif 1158 1159 1160 // Set up the boot classpath. 1161 1162 char* os::format_boot_path(const char* format_string, 1163 const char* home, 1164 int home_len, 1165 char fileSep, 1166 char pathSep) { 1167 assert((fileSep == '/' && pathSep == ':') || 1168 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1169 1170 // Scan the format string to determine the length of the actual 1171 // boot classpath, and handle platform dependencies as well. 1172 int formatted_path_len = 0; 1173 const char* p; 1174 for (p = format_string; *p != 0; ++p) { 1175 if (*p == '%') formatted_path_len += home_len - 1; 1176 ++formatted_path_len; 1177 } 1178 1179 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1180 if (formatted_path == NULL) { 1181 return NULL; 1182 } 1183 1184 // Create boot classpath from format, substituting separator chars and 1185 // java home directory. 1186 char* q = formatted_path; 1187 for (p = format_string; *p != 0; ++p) { 1188 switch (*p) { 1189 case '%': 1190 strcpy(q, home); 1191 q += home_len; 1192 break; 1193 case '/': 1194 *q++ = fileSep; 1195 break; 1196 case ':': 1197 *q++ = pathSep; 1198 break; 1199 default: 1200 *q++ = *p; 1201 } 1202 } 1203 *q = '\0'; 1204 1205 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1206 return formatted_path; 1207 } 1208 1209 // returns a PATH of all entries in the given directory that do not start with a '.' 1210 static char* expand_entries_to_path(char* directory, char fileSep, char pathSep) { 1211 DIR* dir = os::opendir(directory); 1212 if (dir == NULL) return NULL; 1213 1214 char* path = NULL; 1215 size_t path_len = 0; // path length including \0 terminator 1216 1217 size_t directory_len = strlen(directory); 1218 struct dirent *entry; 1219 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal); 1220 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) { 1221 const char* name = entry->d_name; 1222 if (name[0] == '.') continue; 1223 1224 size_t name_len = strlen(name); 1225 size_t needed = directory_len + name_len + 2; 1226 size_t new_len = path_len + needed; 1227 if (path == NULL) { 1228 path = NEW_C_HEAP_ARRAY(char, new_len, mtInternal); 1229 } else { 1230 path = REALLOC_C_HEAP_ARRAY(char, path, new_len, mtInternal); 1231 } 1232 if (path == NULL) 1233 break; 1234 1235 // append <pathSep>directory<fileSep>name 1236 char* p = path; 1237 if (path_len > 0) { 1238 p += (path_len -1); 1239 *p = pathSep; 1240 p++; 1241 } 1242 1243 strcpy(p, directory); 1244 p += directory_len; 1245 1246 *p = fileSep; 1247 p++; 1248 1249 strcpy(p, name); 1250 p += name_len; 1251 1252 path_len = new_len; 1253 } 1254 1255 FREE_C_HEAP_ARRAY(char, dbuf); 1256 os::closedir(dir); 1257 1258 return path; 1259 } 1260 1261 bool os::set_boot_path(char fileSep, char pathSep) { 1262 const char* home = Arguments::get_java_home(); 1263 int home_len = (int)strlen(home); 1264 1265 char* sysclasspath = NULL; 1266 struct stat st; 1267 1268 // modular image if bootmodules.jimage exists 1269 char* jimage = format_boot_path("%/lib/modules/" BOOT_IMAGE_NAME, home, home_len, fileSep, pathSep); 1270 if (jimage == NULL) return false; 1271 bool has_jimage = (os::stat(jimage, &st) == 0); 1272 if (has_jimage) { 1273 Arguments::set_sysclasspath(jimage); 1274 FREE_C_HEAP_ARRAY(char, jimage); 1275 return true; 1276 } 1277 FREE_C_HEAP_ARRAY(char, jimage); 1278 1279 // check if developer build with exploded modules 1280 char* modules_dir = format_boot_path("%/modules", home, home_len, fileSep, pathSep); 1281 if (os::stat(modules_dir, &st) == 0) { 1282 if ((st.st_mode & S_IFDIR) == S_IFDIR) { 1283 sysclasspath = expand_entries_to_path(modules_dir, fileSep, pathSep); 1284 } 1285 } 1286 FREE_C_HEAP_ARRAY(char, modules_dir); 1287 1288 // fallback to classes 1289 if (sysclasspath == NULL) 1290 sysclasspath = format_boot_path("%/classes", home, home_len, fileSep, pathSep); 1291 1292 if (sysclasspath == NULL) return false; 1293 Arguments::set_sysclasspath(sysclasspath); 1294 FREE_C_HEAP_ARRAY(char, sysclasspath); 1295 1296 return true; 1297 } 1298 1299 /* 1300 * Splits a path, based on its separator, the number of 1301 * elements is returned back in n. 1302 * It is the callers responsibility to: 1303 * a> check the value of n, and n may be 0. 1304 * b> ignore any empty path elements 1305 * c> free up the data. 1306 */ 1307 char** os::split_path(const char* path, int* n) { 1308 *n = 0; 1309 if (path == NULL || strlen(path) == 0) { 1310 return NULL; 1311 } 1312 const char psepchar = *os::path_separator(); 1313 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1314 if (inpath == NULL) { 1315 return NULL; 1316 } 1317 strcpy(inpath, path); 1318 int count = 1; 1319 char* p = strchr(inpath, psepchar); 1320 // Get a count of elements to allocate memory 1321 while (p != NULL) { 1322 count++; 1323 p++; 1324 p = strchr(p, psepchar); 1325 } 1326 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1327 if (opath == NULL) { 1328 return NULL; 1329 } 1330 1331 // do the actual splitting 1332 p = inpath; 1333 for (int i = 0 ; i < count ; i++) { 1334 size_t len = strcspn(p, os::path_separator()); 1335 if (len > JVM_MAXPATHLEN) { 1336 return NULL; 1337 } 1338 // allocate the string and add terminator storage 1339 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1340 if (s == NULL) { 1341 return NULL; 1342 } 1343 strncpy(s, p, len); 1344 s[len] = '\0'; 1345 opath[i] = s; 1346 p += len + 1; 1347 } 1348 FREE_C_HEAP_ARRAY(char, inpath); 1349 *n = count; 1350 return opath; 1351 } 1352 1353 void os::set_memory_serialize_page(address page) { 1354 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1355 _mem_serialize_page = (volatile int32_t *)page; 1356 // We initialize the serialization page shift count here 1357 // We assume a cache line size of 64 bytes 1358 assert(SerializePageShiftCount == count, 1359 "thread size changed, fix SerializePageShiftCount constant"); 1360 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1361 } 1362 1363 static volatile intptr_t SerializePageLock = 0; 1364 1365 // This method is called from signal handler when SIGSEGV occurs while the current 1366 // thread tries to store to the "read-only" memory serialize page during state 1367 // transition. 1368 void os::block_on_serialize_page_trap() { 1369 log_debug(safepoint)("Block until the serialize page permission restored"); 1370 1371 // When VMThread is holding the SerializePageLock during modifying the 1372 // access permission of the memory serialize page, the following call 1373 // will block until the permission of that page is restored to rw. 1374 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1375 // this case, it's OK as the signal is synchronous and we know precisely when 1376 // it can occur. 1377 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1378 Thread::muxRelease(&SerializePageLock); 1379 } 1380 1381 // Serialize all thread state variables 1382 void os::serialize_thread_states() { 1383 // On some platforms such as Solaris & Linux, the time duration of the page 1384 // permission restoration is observed to be much longer than expected due to 1385 // scheduler starvation problem etc. To avoid the long synchronization 1386 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1387 // the mutator thread if such case is encountered. See bug 6546278 for details. 1388 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1389 os::protect_memory((char *)os::get_memory_serialize_page(), 1390 os::vm_page_size(), MEM_PROT_READ); 1391 os::protect_memory((char *)os::get_memory_serialize_page(), 1392 os::vm_page_size(), MEM_PROT_RW); 1393 Thread::muxRelease(&SerializePageLock); 1394 } 1395 1396 // Returns true if the current stack pointer is above the stack shadow 1397 // pages, false otherwise. 1398 1399 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method) { 1400 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1401 address sp = current_stack_pointer(); 1402 // Check if we have StackShadowPages above the yellow zone. This parameter 1403 // is dependent on the depth of the maximum VM call stack possible from 1404 // the handler for stack overflow. 'instanceof' in the stack overflow 1405 // handler or a println uses at least 8k stack of VM and native code 1406 // respectively. 1407 const int framesize_in_bytes = 1408 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1409 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1410 * vm_page_size()) + framesize_in_bytes; 1411 // The very lower end of the stack 1412 address stack_limit = thread->stack_base() - thread->stack_size(); 1413 return (sp > (stack_limit + reserved_area)); 1414 } 1415 1416 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1417 assert(min_pages > 0, "sanity"); 1418 if (UseLargePages) { 1419 const size_t max_page_size = region_size / min_pages; 1420 1421 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1422 const size_t page_size = _page_sizes[i]; 1423 if (page_size <= max_page_size) { 1424 if (!must_be_aligned || is_size_aligned(region_size, page_size)) { 1425 return page_size; 1426 } 1427 } 1428 } 1429 } 1430 1431 return vm_page_size(); 1432 } 1433 1434 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1435 return page_size_for_region(region_size, min_pages, true); 1436 } 1437 1438 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1439 return page_size_for_region(region_size, min_pages, false); 1440 } 1441 1442 #ifndef PRODUCT 1443 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1444 { 1445 if (TracePageSizes) { 1446 tty->print("%s: ", str); 1447 for (int i = 0; i < count; ++i) { 1448 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1449 } 1450 tty->cr(); 1451 } 1452 } 1453 1454 void os::trace_page_sizes(const char* str, const size_t region_min_size, 1455 const size_t region_max_size, const size_t page_size, 1456 const char* base, const size_t size) 1457 { 1458 if (TracePageSizes) { 1459 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1460 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1461 " size=" SIZE_FORMAT, 1462 str, region_min_size, region_max_size, 1463 page_size, p2i(base), size); 1464 } 1465 } 1466 #endif // #ifndef PRODUCT 1467 1468 // This is the working definition of a server class machine: 1469 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1470 // because the graphics memory (?) sometimes masks physical memory. 1471 // If you want to change the definition of a server class machine 1472 // on some OS or platform, e.g., >=4GB on Windows platforms, 1473 // then you'll have to parameterize this method based on that state, 1474 // as was done for logical processors here, or replicate and 1475 // specialize this method for each platform. (Or fix os to have 1476 // some inheritance structure and use subclassing. Sigh.) 1477 // If you want some platform to always or never behave as a server 1478 // class machine, change the setting of AlwaysActAsServerClassMachine 1479 // and NeverActAsServerClassMachine in globals*.hpp. 1480 bool os::is_server_class_machine() { 1481 // First check for the early returns 1482 if (NeverActAsServerClassMachine) { 1483 return false; 1484 } 1485 if (AlwaysActAsServerClassMachine) { 1486 return true; 1487 } 1488 // Then actually look at the machine 1489 bool result = false; 1490 const unsigned int server_processors = 2; 1491 const julong server_memory = 2UL * G; 1492 // We seem not to get our full complement of memory. 1493 // We allow some part (1/8?) of the memory to be "missing", 1494 // based on the sizes of DIMMs, and maybe graphics cards. 1495 const julong missing_memory = 256UL * M; 1496 1497 /* Is this a server class machine? */ 1498 if ((os::active_processor_count() >= (int)server_processors) && 1499 (os::physical_memory() >= (server_memory - missing_memory))) { 1500 const unsigned int logical_processors = 1501 VM_Version::logical_processors_per_package(); 1502 if (logical_processors > 1) { 1503 const unsigned int physical_packages = 1504 os::active_processor_count() / logical_processors; 1505 if (physical_packages > server_processors) { 1506 result = true; 1507 } 1508 } else { 1509 result = true; 1510 } 1511 } 1512 return result; 1513 } 1514 1515 void os::SuspendedThreadTask::run() { 1516 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1517 internal_do_task(); 1518 _done = true; 1519 } 1520 1521 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1522 return os::pd_create_stack_guard_pages(addr, bytes); 1523 } 1524 1525 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1526 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1527 if (result != NULL) { 1528 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1529 } 1530 1531 return result; 1532 } 1533 1534 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1535 MEMFLAGS flags) { 1536 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1537 if (result != NULL) { 1538 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1539 MemTracker::record_virtual_memory_type((address)result, flags); 1540 } 1541 1542 return result; 1543 } 1544 1545 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1546 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1547 if (result != NULL) { 1548 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1549 } 1550 return result; 1551 } 1552 1553 void os::split_reserved_memory(char *base, size_t size, 1554 size_t split, bool realloc) { 1555 pd_split_reserved_memory(base, size, split, realloc); 1556 } 1557 1558 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1559 bool res = pd_commit_memory(addr, bytes, executable); 1560 if (res) { 1561 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1562 } 1563 return res; 1564 } 1565 1566 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1567 bool executable) { 1568 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1569 if (res) { 1570 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1571 } 1572 return res; 1573 } 1574 1575 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1576 const char* mesg) { 1577 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1578 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1579 } 1580 1581 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1582 bool executable, const char* mesg) { 1583 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1584 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1585 } 1586 1587 bool os::uncommit_memory(char* addr, size_t bytes) { 1588 bool res; 1589 if (MemTracker::tracking_level() > NMT_minimal) { 1590 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1591 res = pd_uncommit_memory(addr, bytes); 1592 if (res) { 1593 tkr.record((address)addr, bytes); 1594 } 1595 } else { 1596 res = pd_uncommit_memory(addr, bytes); 1597 } 1598 return res; 1599 } 1600 1601 bool os::release_memory(char* addr, size_t bytes) { 1602 bool res; 1603 if (MemTracker::tracking_level() > NMT_minimal) { 1604 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1605 res = pd_release_memory(addr, bytes); 1606 if (res) { 1607 tkr.record((address)addr, bytes); 1608 } 1609 } else { 1610 res = pd_release_memory(addr, bytes); 1611 } 1612 return res; 1613 } 1614 1615 void os::pretouch_memory(char* start, char* end) { 1616 for (volatile char *p = start; p < end; p += os::vm_page_size()) { 1617 *p = 0; 1618 } 1619 } 1620 1621 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1622 char *addr, size_t bytes, bool read_only, 1623 bool allow_exec) { 1624 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1625 if (result != NULL) { 1626 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1627 } 1628 return result; 1629 } 1630 1631 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1632 char *addr, size_t bytes, bool read_only, 1633 bool allow_exec) { 1634 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1635 read_only, allow_exec); 1636 } 1637 1638 bool os::unmap_memory(char *addr, size_t bytes) { 1639 bool result; 1640 if (MemTracker::tracking_level() > NMT_minimal) { 1641 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1642 result = pd_unmap_memory(addr, bytes); 1643 if (result) { 1644 tkr.record((address)addr, bytes); 1645 } 1646 } else { 1647 result = pd_unmap_memory(addr, bytes); 1648 } 1649 return result; 1650 } 1651 1652 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1653 pd_free_memory(addr, bytes, alignment_hint); 1654 } 1655 1656 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1657 pd_realign_memory(addr, bytes, alignment_hint); 1658 } 1659 1660 #ifndef TARGET_OS_FAMILY_windows 1661 /* try to switch state from state "from" to state "to" 1662 * returns the state set after the method is complete 1663 */ 1664 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1665 os::SuspendResume::State to) 1666 { 1667 os::SuspendResume::State result = 1668 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1669 if (result == from) { 1670 // success 1671 return to; 1672 } 1673 return result; 1674 } 1675 #endif 1676 1677 /////////////// Unit tests /////////////// 1678 1679 #ifndef PRODUCT 1680 1681 #define assert_eq(a,b) assert(a == b, SIZE_FORMAT " != " SIZE_FORMAT, a, b) 1682 1683 class TestOS : AllStatic { 1684 static size_t small_page_size() { 1685 return os::vm_page_size(); 1686 } 1687 1688 static size_t large_page_size() { 1689 const size_t large_page_size_example = 4 * M; 1690 return os::page_size_for_region_aligned(large_page_size_example, 1); 1691 } 1692 1693 static void test_page_size_for_region_aligned() { 1694 if (UseLargePages) { 1695 const size_t small_page = small_page_size(); 1696 const size_t large_page = large_page_size(); 1697 1698 if (large_page > small_page) { 1699 size_t num_small_pages_in_large = large_page / small_page; 1700 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large); 1701 1702 assert_eq(page, small_page); 1703 } 1704 } 1705 } 1706 1707 static void test_page_size_for_region_alignment() { 1708 if (UseLargePages) { 1709 const size_t small_page = small_page_size(); 1710 const size_t large_page = large_page_size(); 1711 if (large_page > small_page) { 1712 const size_t unaligned_region = large_page + 17; 1713 size_t page = os::page_size_for_region_aligned(unaligned_region, 1); 1714 assert_eq(page, small_page); 1715 1716 const size_t num_pages = 5; 1717 const size_t aligned_region = large_page * num_pages; 1718 page = os::page_size_for_region_aligned(aligned_region, num_pages); 1719 assert_eq(page, large_page); 1720 } 1721 } 1722 } 1723 1724 static void test_page_size_for_region_unaligned() { 1725 if (UseLargePages) { 1726 // Given exact page size, should return that page size. 1727 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1728 size_t expected = os::_page_sizes[i]; 1729 size_t actual = os::page_size_for_region_unaligned(expected, 1); 1730 assert_eq(expected, actual); 1731 } 1732 1733 // Given slightly larger size than a page size, return the page size. 1734 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1735 size_t expected = os::_page_sizes[i]; 1736 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1); 1737 assert_eq(expected, actual); 1738 } 1739 1740 // Given a slightly smaller size than a page size, 1741 // return the next smaller page size. 1742 if (os::_page_sizes[1] > os::_page_sizes[0]) { 1743 size_t expected = os::_page_sizes[0]; 1744 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1); 1745 assert_eq(actual, expected); 1746 } 1747 1748 // Return small page size for values less than a small page. 1749 size_t small_page = small_page_size(); 1750 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1); 1751 assert_eq(small_page, actual); 1752 } 1753 } 1754 1755 public: 1756 static void run_tests() { 1757 test_page_size_for_region_aligned(); 1758 test_page_size_for_region_alignment(); 1759 test_page_size_for_region_unaligned(); 1760 } 1761 }; 1762 1763 void TestOS_test() { 1764 TestOS::run_tests(); 1765 } 1766 1767 #endif // PRODUCT