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