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 // We need to adapt the configured number of stack protection pages given 320 // in 4K pages to the actual os page size. We must do this before setting 321 // up minimal stack sizes etc. in os::init_2(). 322 JavaThread::set_stack_red_zone_size (align_size_up(StackRedPages * 4 * K, vm_page_size())); 323 JavaThread::set_stack_yellow_zone_size (align_size_up(StackYellowPages * 4 * K, vm_page_size())); 324 JavaThread::set_stack_reserved_zone_size(align_size_up(StackReservedPages * 4 * K, vm_page_size())); 325 JavaThread::set_stack_shadow_zone_size (align_size_up(StackShadowPages * 4 * K, vm_page_size())); 326 327 // VM version initialization identifies some characteristics of the 328 // platform that are used during ergonomic decisions. 329 VM_Version::init_before_ergo(); 330 } 331 332 void os::signal_init() { 333 if (!ReduceSignalUsage) { 334 // Setup JavaThread for processing signals 335 EXCEPTION_MARK; 336 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 337 instanceKlassHandle klass (THREAD, k); 338 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 339 340 const char thread_name[] = "Signal Dispatcher"; 341 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 342 343 // Initialize thread_oop to put it into the system threadGroup 344 Handle thread_group (THREAD, Universe::system_thread_group()); 345 JavaValue result(T_VOID); 346 JavaCalls::call_special(&result, thread_oop, 347 klass, 348 vmSymbols::object_initializer_name(), 349 vmSymbols::threadgroup_string_void_signature(), 350 thread_group, 351 string, 352 CHECK); 353 354 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 355 JavaCalls::call_special(&result, 356 thread_group, 357 group, 358 vmSymbols::add_method_name(), 359 vmSymbols::thread_void_signature(), 360 thread_oop, // ARG 1 361 CHECK); 362 363 os::signal_init_pd(); 364 365 { MutexLocker mu(Threads_lock); 366 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 367 368 // At this point it may be possible that no osthread was created for the 369 // JavaThread due to lack of memory. We would have to throw an exception 370 // in that case. However, since this must work and we do not allow 371 // exceptions anyway, check and abort if this fails. 372 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 373 vm_exit_during_initialization("java.lang.OutOfMemoryError", 374 os::native_thread_creation_failed_msg()); 375 } 376 377 java_lang_Thread::set_thread(thread_oop(), signal_thread); 378 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 379 java_lang_Thread::set_daemon(thread_oop()); 380 381 signal_thread->set_threadObj(thread_oop()); 382 Threads::add(signal_thread); 383 Thread::start(signal_thread); 384 } 385 // Handle ^BREAK 386 os::signal(SIGBREAK, os::user_handler()); 387 } 388 } 389 390 391 void os::terminate_signal_thread() { 392 if (!ReduceSignalUsage) 393 signal_notify(sigexitnum_pd()); 394 } 395 396 397 // --------------------- loading libraries --------------------- 398 399 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 400 extern struct JavaVM_ main_vm; 401 402 static void* _native_java_library = NULL; 403 404 void* os::native_java_library() { 405 if (_native_java_library == NULL) { 406 char buffer[JVM_MAXPATHLEN]; 407 char ebuf[1024]; 408 409 // Try to load verify dll first. In 1.3 java dll depends on it and is not 410 // always able to find it when the loading executable is outside the JDK. 411 // In order to keep working with 1.2 we ignore any loading errors. 412 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 413 "verify")) { 414 dll_load(buffer, ebuf, sizeof(ebuf)); 415 } 416 417 // Load java dll 418 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 419 "java")) { 420 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 421 } 422 if (_native_java_library == NULL) { 423 vm_exit_during_initialization("Unable to load native library", ebuf); 424 } 425 426 #if defined(__OpenBSD__) 427 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 428 // ignore errors 429 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 430 "net")) { 431 dll_load(buffer, ebuf, sizeof(ebuf)); 432 } 433 #endif 434 } 435 return _native_java_library; 436 } 437 438 /* 439 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 440 * If check_lib == true then we are looking for an 441 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 442 * this library is statically linked into the image. 443 * If check_lib == false then we will look for the appropriate symbol in the 444 * executable if agent_lib->is_static_lib() == true or in the shared library 445 * referenced by 'handle'. 446 */ 447 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 448 const char *syms[], size_t syms_len) { 449 assert(agent_lib != NULL, "sanity check"); 450 const char *lib_name; 451 void *handle = agent_lib->os_lib(); 452 void *entryName = NULL; 453 char *agent_function_name; 454 size_t i; 455 456 // If checking then use the agent name otherwise test is_static_lib() to 457 // see how to process this lookup 458 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 459 for (i = 0; i < syms_len; i++) { 460 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 461 if (agent_function_name == NULL) { 462 break; 463 } 464 entryName = dll_lookup(handle, agent_function_name); 465 FREE_C_HEAP_ARRAY(char, agent_function_name); 466 if (entryName != NULL) { 467 break; 468 } 469 } 470 return entryName; 471 } 472 473 // See if the passed in agent is statically linked into the VM image. 474 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 475 size_t syms_len) { 476 void *ret; 477 void *proc_handle; 478 void *save_handle; 479 480 assert(agent_lib != NULL, "sanity check"); 481 if (agent_lib->name() == NULL) { 482 return false; 483 } 484 proc_handle = get_default_process_handle(); 485 // Check for Agent_OnLoad/Attach_lib_name function 486 save_handle = agent_lib->os_lib(); 487 // We want to look in this process' symbol table. 488 agent_lib->set_os_lib(proc_handle); 489 ret = find_agent_function(agent_lib, true, syms, syms_len); 490 if (ret != NULL) { 491 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 492 agent_lib->set_valid(); 493 agent_lib->set_static_lib(true); 494 return true; 495 } 496 agent_lib->set_os_lib(save_handle); 497 return false; 498 } 499 500 // --------------------- heap allocation utilities --------------------- 501 502 char *os::strdup(const char *str, MEMFLAGS flags) { 503 size_t size = strlen(str); 504 char *dup_str = (char *)malloc(size + 1, flags); 505 if (dup_str == NULL) return NULL; 506 strcpy(dup_str, str); 507 return dup_str; 508 } 509 510 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) { 511 char* p = os::strdup(str, flags); 512 if (p == NULL) { 513 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom"); 514 } 515 return p; 516 } 517 518 519 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 520 521 #ifdef ASSERT 522 523 static void verify_memory(void* ptr) { 524 GuardedMemory guarded(ptr); 525 if (!guarded.verify_guards()) { 526 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 527 tty->print_cr("## memory stomp:"); 528 guarded.print_on(tty); 529 fatal("memory stomping error"); 530 } 531 } 532 533 #endif 534 535 // 536 // This function supports testing of the malloc out of memory 537 // condition without really running the system out of memory. 538 // 539 static bool has_reached_max_malloc_test_peak(size_t alloc_size) { 540 if (MallocMaxTestWords > 0) { 541 jint words = (jint)(alloc_size / BytesPerWord); 542 543 if ((cur_malloc_words + words) > MallocMaxTestWords) { 544 return true; 545 } 546 Atomic::add(words, (volatile jint *)&cur_malloc_words); 547 } 548 return false; 549 } 550 551 void* os::malloc(size_t size, MEMFLAGS flags) { 552 return os::malloc(size, flags, CALLER_PC); 553 } 554 555 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 556 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 557 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 558 559 #ifdef ASSERT 560 // checking for the WatcherThread and crash_protection first 561 // since os::malloc can be called when the libjvm.{dll,so} is 562 // first loaded and we don't have a thread yet. 563 // try to find the thread after we see that the watcher thread 564 // exists and has crash protection. 565 WatcherThread *wt = WatcherThread::watcher_thread(); 566 if (wt != NULL && wt->has_crash_protection()) { 567 Thread* thread = Thread::current_or_null(); 568 if (thread == wt) { 569 assert(!wt->has_crash_protection(), 570 "Can't malloc with crash protection from WatcherThread"); 571 } 572 } 573 #endif 574 575 if (size == 0) { 576 // return a valid pointer if size is zero 577 // if NULL is returned the calling functions assume out of memory. 578 size = 1; 579 } 580 581 // NMT support 582 NMT_TrackingLevel level = MemTracker::tracking_level(); 583 size_t nmt_header_size = MemTracker::malloc_header_size(level); 584 585 #ifndef ASSERT 586 const size_t alloc_size = size + nmt_header_size; 587 #else 588 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size); 589 if (size + nmt_header_size > alloc_size) { // Check for rollover. 590 return NULL; 591 } 592 #endif 593 594 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 595 596 // For the test flag -XX:MallocMaxTestWords 597 if (has_reached_max_malloc_test_peak(size)) { 598 return NULL; 599 } 600 601 u_char* ptr; 602 ptr = (u_char*)::malloc(alloc_size); 603 604 #ifdef ASSERT 605 if (ptr == NULL) { 606 return NULL; 607 } 608 // Wrap memory with guard 609 GuardedMemory guarded(ptr, size + nmt_header_size); 610 ptr = guarded.get_user_ptr(); 611 #endif 612 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 613 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 614 breakpoint(); 615 } 616 debug_only(if (paranoid) verify_memory(ptr)); 617 if (PrintMalloc && tty != NULL) { 618 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 619 } 620 621 // we do not track guard memory 622 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level); 623 } 624 625 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 626 return os::realloc(memblock, size, flags, CALLER_PC); 627 } 628 629 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 630 631 // For the test flag -XX:MallocMaxTestWords 632 if (has_reached_max_malloc_test_peak(size)) { 633 return NULL; 634 } 635 636 #ifndef ASSERT 637 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 638 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 639 // NMT support 640 void* membase = MemTracker::record_free(memblock); 641 NMT_TrackingLevel level = MemTracker::tracking_level(); 642 size_t nmt_header_size = MemTracker::malloc_header_size(level); 643 void* ptr = ::realloc(membase, size + nmt_header_size); 644 return MemTracker::record_malloc(ptr, size, memflags, stack, level); 645 #else 646 if (memblock == NULL) { 647 return os::malloc(size, memflags, stack); 648 } 649 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 650 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock)); 651 breakpoint(); 652 } 653 // NMT support 654 void* membase = MemTracker::malloc_base(memblock); 655 verify_memory(membase); 656 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 657 if (size == 0) { 658 return NULL; 659 } 660 // always move the block 661 void* ptr = os::malloc(size, memflags, stack); 662 if (PrintMalloc && tty != NULL) { 663 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr)); 664 } 665 // Copy to new memory if malloc didn't fail 666 if ( ptr != NULL ) { 667 GuardedMemory guarded(MemTracker::malloc_base(memblock)); 668 // Guard's user data contains NMT header 669 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock); 670 memcpy(ptr, memblock, MIN2(size, memblock_size)); 671 if (paranoid) verify_memory(MemTracker::malloc_base(ptr)); 672 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 673 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr)); 674 breakpoint(); 675 } 676 os::free(memblock); 677 } 678 return ptr; 679 #endif 680 } 681 682 683 void os::free(void *memblock) { 684 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 685 #ifdef ASSERT 686 if (memblock == NULL) return; 687 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 688 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock)); 689 breakpoint(); 690 } 691 void* membase = MemTracker::record_free(memblock); 692 verify_memory(membase); 693 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 694 695 GuardedMemory guarded(membase); 696 size_t size = guarded.get_user_size(); 697 inc_stat_counter(&free_bytes, size); 698 membase = guarded.release_for_freeing(); 699 if (PrintMalloc && tty != NULL) { 700 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase); 701 } 702 ::free(membase); 703 #else 704 void* membase = MemTracker::record_free(memblock); 705 ::free(membase); 706 #endif 707 } 708 709 void os::init_random(long initval) { 710 _rand_seed = initval; 711 } 712 713 714 long os::random() { 715 /* standard, well-known linear congruential random generator with 716 * next_rand = (16807*seed) mod (2**31-1) 717 * see 718 * (1) "Random Number Generators: Good Ones Are Hard to Find", 719 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 720 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 721 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 722 */ 723 const long a = 16807; 724 const unsigned long m = 2147483647; 725 const long q = m / a; assert(q == 127773, "weird math"); 726 const long r = m % a; assert(r == 2836, "weird math"); 727 728 // compute az=2^31p+q 729 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 730 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 731 lo += (hi & 0x7FFF) << 16; 732 733 // if q overflowed, ignore the overflow and increment q 734 if (lo > m) { 735 lo &= m; 736 ++lo; 737 } 738 lo += hi >> 15; 739 740 // if (p+q) overflowed, ignore the overflow and increment (p+q) 741 if (lo > m) { 742 lo &= m; 743 ++lo; 744 } 745 return (_rand_seed = lo); 746 } 747 748 // The INITIALIZED state is distinguished from the SUSPENDED state because the 749 // conditions in which a thread is first started are different from those in which 750 // a suspension is resumed. These differences make it hard for us to apply the 751 // tougher checks when starting threads that we want to do when resuming them. 752 // However, when start_thread is called as a result of Thread.start, on a Java 753 // thread, the operation is synchronized on the Java Thread object. So there 754 // cannot be a race to start the thread and hence for the thread to exit while 755 // we are working on it. Non-Java threads that start Java threads either have 756 // to do so in a context in which races are impossible, or should do appropriate 757 // locking. 758 759 void os::start_thread(Thread* thread) { 760 // guard suspend/resume 761 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 762 OSThread* osthread = thread->osthread(); 763 osthread->set_state(RUNNABLE); 764 pd_start_thread(thread); 765 } 766 767 void os::abort(bool dump_core) { 768 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL); 769 } 770 771 //--------------------------------------------------------------------------- 772 // Helper functions for fatal error handler 773 774 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 775 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 776 777 int cols = 0; 778 int cols_per_line = 0; 779 switch (unitsize) { 780 case 1: cols_per_line = 16; break; 781 case 2: cols_per_line = 8; break; 782 case 4: cols_per_line = 4; break; 783 case 8: cols_per_line = 2; break; 784 default: return; 785 } 786 787 address p = start; 788 st->print(PTR_FORMAT ": ", p2i(start)); 789 while (p < end) { 790 switch (unitsize) { 791 case 1: st->print("%02x", *(u1*)p); break; 792 case 2: st->print("%04x", *(u2*)p); break; 793 case 4: st->print("%08x", *(u4*)p); break; 794 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 795 } 796 p += unitsize; 797 cols++; 798 if (cols >= cols_per_line && p < end) { 799 cols = 0; 800 st->cr(); 801 st->print(PTR_FORMAT ": ", p2i(p)); 802 } else { 803 st->print(" "); 804 } 805 } 806 st->cr(); 807 } 808 809 void os::print_environment_variables(outputStream* st, const char** env_list) { 810 if (env_list) { 811 st->print_cr("Environment Variables:"); 812 813 for (int i = 0; env_list[i] != NULL; i++) { 814 char *envvar = ::getenv(env_list[i]); 815 if (envvar != NULL) { 816 st->print("%s", env_list[i]); 817 st->print("="); 818 st->print_cr("%s", envvar); 819 } 820 } 821 } 822 } 823 824 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) { 825 // cpu 826 st->print("CPU:"); 827 st->print("total %d", os::processor_count()); 828 // It's not safe to query number of active processors after crash 829 // st->print("(active %d)", os::active_processor_count()); 830 st->print(" %s", VM_Version::features_string()); 831 st->cr(); 832 pd_print_cpu_info(st, buf, buflen); 833 } 834 835 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version 836 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) { 837 st->print("Host: "); 838 #ifndef PRODUCT 839 if (get_host_name(buf, buflen)) { 840 st->print("%s, ", buf); 841 } 842 #endif // PRODUCT 843 get_summary_cpu_info(buf, buflen); 844 st->print("%s, ", buf); 845 size_t mem = physical_memory()/G; 846 if (mem == 0) { // for low memory systems 847 mem = physical_memory()/M; 848 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem); 849 } else { 850 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem); 851 } 852 get_summary_os_info(buf, buflen); 853 st->print_raw(buf); 854 st->cr(); 855 } 856 857 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) { 858 const int secs_per_day = 86400; 859 const int secs_per_hour = 3600; 860 const int secs_per_min = 60; 861 862 time_t tloc; 863 (void)time(&tloc); 864 char* timestring = ctime(&tloc); // ctime adds newline. 865 // edit out the newline 866 char* nl = strchr(timestring, '\n'); 867 if (nl != NULL) { 868 *nl = '\0'; 869 } 870 871 struct tm tz; 872 if (localtime_pd(&tloc, &tz) != NULL) { 873 ::strftime(buf, buflen, "%Z", &tz); 874 st->print("Time: %s %s", timestring, buf); 875 } else { 876 st->print("Time: %s", timestring); 877 } 878 879 double t = os::elapsedTime(); 880 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 881 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 882 // before printf. We lost some precision, but who cares? 883 int eltime = (int)t; // elapsed time in seconds 884 885 // print elapsed time in a human-readable format: 886 int eldays = eltime / secs_per_day; 887 int day_secs = eldays * secs_per_day; 888 int elhours = (eltime - day_secs) / secs_per_hour; 889 int hour_secs = elhours * secs_per_hour; 890 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 891 int minute_secs = elmins * secs_per_min; 892 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 893 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 894 } 895 896 // moved from debug.cpp (used to be find()) but still called from there 897 // The verbose parameter is only set by the debug code in one case 898 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 899 address addr = (address)x; 900 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 901 if (b != NULL) { 902 if (b->is_buffer_blob()) { 903 // the interpreter is generated into a buffer blob 904 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 905 if (i != NULL) { 906 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin())); 907 i->print_on(st); 908 return; 909 } 910 if (Interpreter::contains(addr)) { 911 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 912 " (not bytecode specific)", p2i(addr)); 913 return; 914 } 915 // 916 if (AdapterHandlerLibrary::contains(b)) { 917 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin())); 918 AdapterHandlerLibrary::print_handler_on(st, b); 919 } 920 // the stubroutines are generated into a buffer blob 921 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 922 if (d != NULL) { 923 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin())); 924 d->print_on(st); 925 st->cr(); 926 return; 927 } 928 if (StubRoutines::contains(addr)) { 929 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr)); 930 return; 931 } 932 // the InlineCacheBuffer is using stubs generated into a buffer blob 933 if (InlineCacheBuffer::contains(addr)) { 934 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr)); 935 return; 936 } 937 VtableStub* v = VtableStubs::stub_containing(addr); 938 if (v != NULL) { 939 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point())); 940 v->print_on(st); 941 st->cr(); 942 return; 943 } 944 } 945 nmethod* nm = b->as_nmethod_or_null(); 946 if (nm != NULL) { 947 ResourceMark rm; 948 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 949 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm)); 950 if (verbose) { 951 st->print(" for "); 952 nm->method()->print_value_on(st); 953 } 954 st->cr(); 955 nm->print_nmethod(verbose); 956 return; 957 } 958 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin())); 959 b->print_on(st); 960 return; 961 } 962 963 if (Universe::heap()->is_in(addr)) { 964 HeapWord* p = Universe::heap()->block_start(addr); 965 bool print = false; 966 // If we couldn't find it it just may mean that heap wasn't parsable 967 // See if we were just given an oop directly 968 if (p != NULL && Universe::heap()->block_is_obj(p)) { 969 print = true; 970 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 971 p = (HeapWord*) addr; 972 print = true; 973 } 974 if (print) { 975 if (p == (HeapWord*) addr) { 976 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr)); 977 } else { 978 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p)); 979 } 980 oop(p)->print_on(st); 981 return; 982 } 983 } else { 984 if (Universe::heap()->is_in_reserved(addr)) { 985 st->print_cr(INTPTR_FORMAT " is an unallocated location " 986 "in the heap", p2i(addr)); 987 return; 988 } 989 } 990 if (JNIHandles::is_global_handle((jobject) addr)) { 991 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr)); 992 return; 993 } 994 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 995 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr)); 996 return; 997 } 998 #ifndef PRODUCT 999 // we don't keep the block list in product mode 1000 if (JNIHandleBlock::any_contains((jobject) addr)) { 1001 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr)); 1002 return; 1003 } 1004 #endif 1005 1006 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1007 // Check for privilege stack 1008 if (thread->privileged_stack_top() != NULL && 1009 thread->privileged_stack_top()->contains(addr)) { 1010 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1011 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread)); 1012 if (verbose) thread->print_on(st); 1013 return; 1014 } 1015 // If the addr is a java thread print information about that. 1016 if (addr == (address)thread) { 1017 if (verbose) { 1018 thread->print_on(st); 1019 } else { 1020 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr)); 1021 } 1022 return; 1023 } 1024 // If the addr is in the stack region for this thread then report that 1025 // and print thread info 1026 if (thread->on_local_stack(addr)) { 1027 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1028 INTPTR_FORMAT, p2i(addr), p2i(thread)); 1029 if (verbose) thread->print_on(st); 1030 return; 1031 } 1032 1033 } 1034 1035 // Check if in metaspace and print types that have vptrs (only method now) 1036 if (Metaspace::contains(addr)) { 1037 if (Method::has_method_vptr((const void*)addr)) { 1038 ((Method*)addr)->print_value_on(st); 1039 st->cr(); 1040 } else { 1041 // Use addr->print() from the debugger instead (not here) 1042 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr)); 1043 } 1044 return; 1045 } 1046 1047 // Try an OS specific find 1048 if (os::find(addr, st)) { 1049 return; 1050 } 1051 1052 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr)); 1053 } 1054 1055 // Looks like all platforms except IA64 can use the same function to check 1056 // if C stack is walkable beyond current frame. The check for fp() is not 1057 // necessary on Sparc, but it's harmless. 1058 bool os::is_first_C_frame(frame* fr) { 1059 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32) 1060 // On IA64 we have to check if the callers bsp is still valid 1061 // (i.e. within the register stack bounds). 1062 // Notice: this only works for threads created by the VM and only if 1063 // we walk the current stack!!! If we want to be able to walk 1064 // arbitrary other threads, we'll have to somehow store the thread 1065 // object in the frame. 1066 Thread *thread = Thread::current(); 1067 if ((address)fr->fp() <= 1068 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1069 // This check is a little hacky, because on Linux the first C 1070 // frame's ('start_thread') register stack frame starts at 1071 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1072 // ('__pthread_bound_body') register stack frame seems to really 1073 // start at "register_stack_base". 1074 return true; 1075 } else { 1076 return false; 1077 } 1078 #elif defined(IA64) && defined(_WIN32) 1079 return true; 1080 #else 1081 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1082 // Check usp first, because if that's bad the other accessors may fault 1083 // on some architectures. Ditto ufp second, etc. 1084 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1085 // sp on amd can be 32 bit aligned. 1086 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1087 1088 uintptr_t usp = (uintptr_t)fr->sp(); 1089 if ((usp & sp_align_mask) != 0) return true; 1090 1091 uintptr_t ufp = (uintptr_t)fr->fp(); 1092 if ((ufp & fp_align_mask) != 0) return true; 1093 1094 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1095 if ((old_sp & sp_align_mask) != 0) return true; 1096 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1097 1098 uintptr_t old_fp = (uintptr_t)fr->link(); 1099 if ((old_fp & fp_align_mask) != 0) return true; 1100 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1101 1102 // stack grows downwards; if old_fp is below current fp or if the stack 1103 // frame is too large, either the stack is corrupted or fp is not saved 1104 // on stack (i.e. on x86, ebp may be used as general register). The stack 1105 // is not walkable beyond current frame. 1106 if (old_fp < ufp) return true; 1107 if (old_fp - ufp > 64 * K) return true; 1108 1109 return false; 1110 #endif 1111 } 1112 1113 #ifdef ASSERT 1114 extern "C" void test_random() { 1115 const double m = 2147483647; 1116 double mean = 0.0, variance = 0.0, t; 1117 long reps = 10000; 1118 unsigned long seed = 1; 1119 1120 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1121 os::init_random(seed); 1122 long num; 1123 for (int k = 0; k < reps; k++) { 1124 num = os::random(); 1125 double u = (double)num / m; 1126 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1127 1128 // calculate mean and variance of the random sequence 1129 mean += u; 1130 variance += (u*u); 1131 } 1132 mean /= reps; 1133 variance /= (reps - 1); 1134 1135 assert(num == 1043618065, "bad seed"); 1136 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1137 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1138 const double eps = 0.0001; 1139 t = fabsd(mean - 0.5018); 1140 assert(t < eps, "bad mean"); 1141 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1142 assert(t < eps, "bad variance"); 1143 } 1144 #endif 1145 1146 1147 // Set up the boot classpath. 1148 1149 char* os::format_boot_path(const char* format_string, 1150 const char* home, 1151 int home_len, 1152 char fileSep, 1153 char pathSep) { 1154 assert((fileSep == '/' && pathSep == ':') || 1155 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1156 1157 // Scan the format string to determine the length of the actual 1158 // boot classpath, and handle platform dependencies as well. 1159 int formatted_path_len = 0; 1160 const char* p; 1161 for (p = format_string; *p != 0; ++p) { 1162 if (*p == '%') formatted_path_len += home_len - 1; 1163 ++formatted_path_len; 1164 } 1165 1166 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1167 if (formatted_path == NULL) { 1168 return NULL; 1169 } 1170 1171 // Create boot classpath from format, substituting separator chars and 1172 // java home directory. 1173 char* q = formatted_path; 1174 for (p = format_string; *p != 0; ++p) { 1175 switch (*p) { 1176 case '%': 1177 strcpy(q, home); 1178 q += home_len; 1179 break; 1180 case '/': 1181 *q++ = fileSep; 1182 break; 1183 case ':': 1184 *q++ = pathSep; 1185 break; 1186 default: 1187 *q++ = *p; 1188 } 1189 } 1190 *q = '\0'; 1191 1192 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1193 return formatted_path; 1194 } 1195 1196 // returns a PATH of all entries in the given directory that do not start with a '.' 1197 static char* expand_entries_to_path(char* directory, char fileSep, char pathSep) { 1198 DIR* dir = os::opendir(directory); 1199 if (dir == NULL) return NULL; 1200 1201 char* path = NULL; 1202 size_t path_len = 0; // path length including \0 terminator 1203 1204 size_t directory_len = strlen(directory); 1205 struct dirent *entry; 1206 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal); 1207 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) { 1208 const char* name = entry->d_name; 1209 if (name[0] == '.') continue; 1210 1211 size_t name_len = strlen(name); 1212 size_t needed = directory_len + name_len + 2; 1213 size_t new_len = path_len + needed; 1214 if (path == NULL) { 1215 path = NEW_C_HEAP_ARRAY(char, new_len, mtInternal); 1216 } else { 1217 path = REALLOC_C_HEAP_ARRAY(char, path, new_len, mtInternal); 1218 } 1219 if (path == NULL) 1220 break; 1221 1222 // append <pathSep>directory<fileSep>name 1223 char* p = path; 1224 if (path_len > 0) { 1225 p += (path_len -1); 1226 *p = pathSep; 1227 p++; 1228 } 1229 1230 strcpy(p, directory); 1231 p += directory_len; 1232 1233 *p = fileSep; 1234 p++; 1235 1236 strcpy(p, name); 1237 p += name_len; 1238 1239 path_len = new_len; 1240 } 1241 1242 FREE_C_HEAP_ARRAY(char, dbuf); 1243 os::closedir(dir); 1244 1245 return path; 1246 } 1247 1248 bool os::set_boot_path(char fileSep, char pathSep) { 1249 const char* home = Arguments::get_java_home(); 1250 int home_len = (int)strlen(home); 1251 1252 char* sysclasspath = NULL; 1253 struct stat st; 1254 1255 // modular image if bootmodules.jimage exists 1256 char* jimage = format_boot_path("%/lib/modules/" BOOT_IMAGE_NAME, home, home_len, fileSep, pathSep); 1257 if (jimage == NULL) return false; 1258 bool has_jimage = (os::stat(jimage, &st) == 0); 1259 if (has_jimage) { 1260 Arguments::set_sysclasspath(jimage); 1261 FREE_C_HEAP_ARRAY(char, jimage); 1262 return true; 1263 } 1264 FREE_C_HEAP_ARRAY(char, jimage); 1265 1266 // check if developer build with exploded modules 1267 char* modules_dir = format_boot_path("%/modules", home, home_len, fileSep, pathSep); 1268 if (os::stat(modules_dir, &st) == 0) { 1269 if ((st.st_mode & S_IFDIR) == S_IFDIR) { 1270 sysclasspath = expand_entries_to_path(modules_dir, fileSep, pathSep); 1271 } 1272 } 1273 FREE_C_HEAP_ARRAY(char, modules_dir); 1274 1275 // fallback to classes 1276 if (sysclasspath == NULL) 1277 sysclasspath = format_boot_path("%/classes", home, home_len, fileSep, pathSep); 1278 1279 if (sysclasspath == NULL) return false; 1280 Arguments::set_sysclasspath(sysclasspath); 1281 FREE_C_HEAP_ARRAY(char, sysclasspath); 1282 1283 return true; 1284 } 1285 1286 /* 1287 * Splits a path, based on its separator, the number of 1288 * elements is returned back in n. 1289 * It is the callers responsibility to: 1290 * a> check the value of n, and n may be 0. 1291 * b> ignore any empty path elements 1292 * c> free up the data. 1293 */ 1294 char** os::split_path(const char* path, int* n) { 1295 *n = 0; 1296 if (path == NULL || strlen(path) == 0) { 1297 return NULL; 1298 } 1299 const char psepchar = *os::path_separator(); 1300 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1301 if (inpath == NULL) { 1302 return NULL; 1303 } 1304 strcpy(inpath, path); 1305 int count = 1; 1306 char* p = strchr(inpath, psepchar); 1307 // Get a count of elements to allocate memory 1308 while (p != NULL) { 1309 count++; 1310 p++; 1311 p = strchr(p, psepchar); 1312 } 1313 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1314 if (opath == NULL) { 1315 return NULL; 1316 } 1317 1318 // do the actual splitting 1319 p = inpath; 1320 for (int i = 0 ; i < count ; i++) { 1321 size_t len = strcspn(p, os::path_separator()); 1322 if (len > JVM_MAXPATHLEN) { 1323 return NULL; 1324 } 1325 // allocate the string and add terminator storage 1326 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1327 if (s == NULL) { 1328 return NULL; 1329 } 1330 strncpy(s, p, len); 1331 s[len] = '\0'; 1332 opath[i] = s; 1333 p += len + 1; 1334 } 1335 FREE_C_HEAP_ARRAY(char, inpath); 1336 *n = count; 1337 return opath; 1338 } 1339 1340 void os::set_memory_serialize_page(address page) { 1341 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1342 _mem_serialize_page = (volatile int32_t *)page; 1343 // We initialize the serialization page shift count here 1344 // We assume a cache line size of 64 bytes 1345 assert(SerializePageShiftCount == count, 1346 "thread size changed, fix SerializePageShiftCount constant"); 1347 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1348 } 1349 1350 static volatile intptr_t SerializePageLock = 0; 1351 1352 // This method is called from signal handler when SIGSEGV occurs while the current 1353 // thread tries to store to the "read-only" memory serialize page during state 1354 // transition. 1355 void os::block_on_serialize_page_trap() { 1356 log_debug(safepoint)("Block until the serialize page permission restored"); 1357 1358 // When VMThread is holding the SerializePageLock during modifying the 1359 // access permission of the memory serialize page, the following call 1360 // will block until the permission of that page is restored to rw. 1361 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1362 // this case, it's OK as the signal is synchronous and we know precisely when 1363 // it can occur. 1364 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1365 Thread::muxRelease(&SerializePageLock); 1366 } 1367 1368 // Serialize all thread state variables 1369 void os::serialize_thread_states() { 1370 // On some platforms such as Solaris & Linux, the time duration of the page 1371 // permission restoration is observed to be much longer than expected due to 1372 // scheduler starvation problem etc. To avoid the long synchronization 1373 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1374 // the mutator thread if such case is encountered. See bug 6546278 for details. 1375 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1376 os::protect_memory((char *)os::get_memory_serialize_page(), 1377 os::vm_page_size(), MEM_PROT_READ); 1378 os::protect_memory((char *)os::get_memory_serialize_page(), 1379 os::vm_page_size(), MEM_PROT_RW); 1380 Thread::muxRelease(&SerializePageLock); 1381 } 1382 1383 // Returns true if the current stack pointer is above the stack shadow 1384 // pages, false otherwise. 1385 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method) { 1386 if (!thread->is_Java_thread()) return false; 1387 address sp = current_stack_pointer(); 1388 // Check if we have StackShadowPages above the yellow zone. This parameter 1389 // is dependent on the depth of the maximum VM call stack possible from 1390 // the handler for stack overflow. 'instanceof' in the stack overflow 1391 // handler or a println uses at least 8k stack of VM and native code 1392 // respectively. 1393 const int framesize_in_bytes = 1394 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1395 1396 assert((thread->stack_base() - thread->stack_size()) + 1397 (JavaThread::stack_guard_zone_size() + 1398 JavaThread::stack_shadow_zone_size() + framesize_in_bytes) == 1399 ((JavaThread*)thread)->stack_overflow_limit() + framesize_in_bytes, "sanity"); 1400 1401 return (sp > ((JavaThread*)thread)->stack_overflow_limit() + framesize_in_bytes); 1402 } 1403 1404 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1405 assert(min_pages > 0, "sanity"); 1406 if (UseLargePages) { 1407 const size_t max_page_size = region_size / min_pages; 1408 1409 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1410 const size_t page_size = _page_sizes[i]; 1411 if (page_size <= max_page_size) { 1412 if (!must_be_aligned || is_size_aligned(region_size, page_size)) { 1413 return page_size; 1414 } 1415 } 1416 } 1417 } 1418 1419 return vm_page_size(); 1420 } 1421 1422 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1423 return page_size_for_region(region_size, min_pages, true); 1424 } 1425 1426 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1427 return page_size_for_region(region_size, min_pages, false); 1428 } 1429 1430 #ifndef PRODUCT 1431 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1432 { 1433 if (TracePageSizes) { 1434 tty->print("%s: ", str); 1435 for (int i = 0; i < count; ++i) { 1436 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1437 } 1438 tty->cr(); 1439 } 1440 } 1441 1442 void os::trace_page_sizes(const char* str, const size_t region_min_size, 1443 const size_t region_max_size, const size_t page_size, 1444 const char* base, const size_t size) 1445 { 1446 if (TracePageSizes) { 1447 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1448 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1449 " size=" SIZE_FORMAT, 1450 str, region_min_size, region_max_size, 1451 page_size, p2i(base), size); 1452 } 1453 } 1454 #endif // #ifndef PRODUCT 1455 1456 // This is the working definition of a server class machine: 1457 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1458 // because the graphics memory (?) sometimes masks physical memory. 1459 // If you want to change the definition of a server class machine 1460 // on some OS or platform, e.g., >=4GB on Windows platforms, 1461 // then you'll have to parameterize this method based on that state, 1462 // as was done for logical processors here, or replicate and 1463 // specialize this method for each platform. (Or fix os to have 1464 // some inheritance structure and use subclassing. Sigh.) 1465 // If you want some platform to always or never behave as a server 1466 // class machine, change the setting of AlwaysActAsServerClassMachine 1467 // and NeverActAsServerClassMachine in globals*.hpp. 1468 bool os::is_server_class_machine() { 1469 // First check for the early returns 1470 if (NeverActAsServerClassMachine) { 1471 return false; 1472 } 1473 if (AlwaysActAsServerClassMachine) { 1474 return true; 1475 } 1476 // Then actually look at the machine 1477 bool result = false; 1478 const unsigned int server_processors = 2; 1479 const julong server_memory = 2UL * G; 1480 // We seem not to get our full complement of memory. 1481 // We allow some part (1/8?) of the memory to be "missing", 1482 // based on the sizes of DIMMs, and maybe graphics cards. 1483 const julong missing_memory = 256UL * M; 1484 1485 /* Is this a server class machine? */ 1486 if ((os::active_processor_count() >= (int)server_processors) && 1487 (os::physical_memory() >= (server_memory - missing_memory))) { 1488 const unsigned int logical_processors = 1489 VM_Version::logical_processors_per_package(); 1490 if (logical_processors > 1) { 1491 const unsigned int physical_packages = 1492 os::active_processor_count() / logical_processors; 1493 if (physical_packages >= server_processors) { 1494 result = true; 1495 } 1496 } else { 1497 result = true; 1498 } 1499 } 1500 return result; 1501 } 1502 1503 void os::SuspendedThreadTask::run() { 1504 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1505 internal_do_task(); 1506 _done = true; 1507 } 1508 1509 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1510 return os::pd_create_stack_guard_pages(addr, bytes); 1511 } 1512 1513 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1514 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1515 if (result != NULL) { 1516 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1517 } 1518 1519 return result; 1520 } 1521 1522 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1523 MEMFLAGS flags) { 1524 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1525 if (result != NULL) { 1526 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1527 MemTracker::record_virtual_memory_type((address)result, flags); 1528 } 1529 1530 return result; 1531 } 1532 1533 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1534 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1535 if (result != NULL) { 1536 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1537 } 1538 return result; 1539 } 1540 1541 void os::split_reserved_memory(char *base, size_t size, 1542 size_t split, bool realloc) { 1543 pd_split_reserved_memory(base, size, split, realloc); 1544 } 1545 1546 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1547 bool res = pd_commit_memory(addr, bytes, executable); 1548 if (res) { 1549 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1550 } 1551 return res; 1552 } 1553 1554 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1555 bool executable) { 1556 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1557 if (res) { 1558 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1559 } 1560 return res; 1561 } 1562 1563 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1564 const char* mesg) { 1565 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1566 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1567 } 1568 1569 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1570 bool executable, const char* mesg) { 1571 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1572 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1573 } 1574 1575 bool os::uncommit_memory(char* addr, size_t bytes) { 1576 bool res; 1577 if (MemTracker::tracking_level() > NMT_minimal) { 1578 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1579 res = pd_uncommit_memory(addr, bytes); 1580 if (res) { 1581 tkr.record((address)addr, bytes); 1582 } 1583 } else { 1584 res = pd_uncommit_memory(addr, bytes); 1585 } 1586 return res; 1587 } 1588 1589 bool os::release_memory(char* addr, size_t bytes) { 1590 bool res; 1591 if (MemTracker::tracking_level() > NMT_minimal) { 1592 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1593 res = pd_release_memory(addr, bytes); 1594 if (res) { 1595 tkr.record((address)addr, bytes); 1596 } 1597 } else { 1598 res = pd_release_memory(addr, bytes); 1599 } 1600 return res; 1601 } 1602 1603 void os::pretouch_memory(char* start, char* end) { 1604 for (volatile char *p = start; p < end; p += os::vm_page_size()) { 1605 *p = 0; 1606 } 1607 } 1608 1609 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1610 char *addr, size_t bytes, bool read_only, 1611 bool allow_exec) { 1612 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1613 if (result != NULL) { 1614 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1615 } 1616 return result; 1617 } 1618 1619 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1620 char *addr, size_t bytes, bool read_only, 1621 bool allow_exec) { 1622 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1623 read_only, allow_exec); 1624 } 1625 1626 bool os::unmap_memory(char *addr, size_t bytes) { 1627 bool result; 1628 if (MemTracker::tracking_level() > NMT_minimal) { 1629 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1630 result = pd_unmap_memory(addr, bytes); 1631 if (result) { 1632 tkr.record((address)addr, bytes); 1633 } 1634 } else { 1635 result = pd_unmap_memory(addr, bytes); 1636 } 1637 return result; 1638 } 1639 1640 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1641 pd_free_memory(addr, bytes, alignment_hint); 1642 } 1643 1644 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1645 pd_realign_memory(addr, bytes, alignment_hint); 1646 } 1647 1648 #ifndef TARGET_OS_FAMILY_windows 1649 /* try to switch state from state "from" to state "to" 1650 * returns the state set after the method is complete 1651 */ 1652 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1653 os::SuspendResume::State to) 1654 { 1655 os::SuspendResume::State result = 1656 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1657 if (result == from) { 1658 // success 1659 return to; 1660 } 1661 return result; 1662 } 1663 #endif 1664 1665 /////////////// Unit tests /////////////// 1666 1667 #ifndef PRODUCT 1668 1669 #define assert_eq(a,b) assert(a == b, SIZE_FORMAT " != " SIZE_FORMAT, a, b) 1670 1671 class TestOS : AllStatic { 1672 static size_t small_page_size() { 1673 return os::vm_page_size(); 1674 } 1675 1676 static size_t large_page_size() { 1677 const size_t large_page_size_example = 4 * M; 1678 return os::page_size_for_region_aligned(large_page_size_example, 1); 1679 } 1680 1681 static void test_page_size_for_region_aligned() { 1682 if (UseLargePages) { 1683 const size_t small_page = small_page_size(); 1684 const size_t large_page = large_page_size(); 1685 1686 if (large_page > small_page) { 1687 size_t num_small_pages_in_large = large_page / small_page; 1688 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large); 1689 1690 assert_eq(page, small_page); 1691 } 1692 } 1693 } 1694 1695 static void test_page_size_for_region_alignment() { 1696 if (UseLargePages) { 1697 const size_t small_page = small_page_size(); 1698 const size_t large_page = large_page_size(); 1699 if (large_page > small_page) { 1700 const size_t unaligned_region = large_page + 17; 1701 size_t page = os::page_size_for_region_aligned(unaligned_region, 1); 1702 assert_eq(page, small_page); 1703 1704 const size_t num_pages = 5; 1705 const size_t aligned_region = large_page * num_pages; 1706 page = os::page_size_for_region_aligned(aligned_region, num_pages); 1707 assert_eq(page, large_page); 1708 } 1709 } 1710 } 1711 1712 static void test_page_size_for_region_unaligned() { 1713 if (UseLargePages) { 1714 // Given exact page size, should return that page size. 1715 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1716 size_t expected = os::_page_sizes[i]; 1717 size_t actual = os::page_size_for_region_unaligned(expected, 1); 1718 assert_eq(expected, actual); 1719 } 1720 1721 // Given slightly larger size than a page size, return the page size. 1722 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1723 size_t expected = os::_page_sizes[i]; 1724 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1); 1725 assert_eq(expected, actual); 1726 } 1727 1728 // Given a slightly smaller size than a page size, 1729 // return the next smaller page size. 1730 if (os::_page_sizes[1] > os::_page_sizes[0]) { 1731 size_t expected = os::_page_sizes[0]; 1732 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1); 1733 assert_eq(actual, expected); 1734 } 1735 1736 // Return small page size for values less than a small page. 1737 size_t small_page = small_page_size(); 1738 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1); 1739 assert_eq(small_page, actual); 1740 } 1741 } 1742 1743 public: 1744 static void run_tests() { 1745 test_page_size_for_region_aligned(); 1746 test_page_size_for_region_alignment(); 1747 test_page_size_for_region_unaligned(); 1748 } 1749 }; 1750 1751 void TestOS_test() { 1752 TestOS::run_tests(); 1753 } 1754 1755 #endif // PRODUCT