os.cpp revision 10420:c558850fac57
1/* 2 * Copyright (c) 1997, 2016, 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 65OSThread* os::_starting_thread = NULL; 66address os::_polling_page = NULL; 67volatile int32_t* os::_mem_serialize_page = NULL; 68uintptr_t os::_serialize_page_mask = 0; 69long os::_rand_seed = 1; 70int os::_processor_count = 0; 71size_t os::_page_sizes[os::page_sizes_max]; 72 73#ifndef PRODUCT 74julong os::num_mallocs = 0; // # of calls to malloc/realloc 75julong os::alloc_bytes = 0; // # of bytes allocated 76julong os::num_frees = 0; // # of calls to free 77julong os::free_bytes = 0; // # of bytes freed 78#endif 79 80static juint cur_malloc_words = 0; // current size for MallocMaxTestWords 81 82void 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. 96char* 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 180OSReturn 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() 203OSReturn 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 231static 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::jdk_internal_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 314void 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 332void 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 391void os::terminate_signal_thread() { 392 if (!ReduceSignalUsage) 393 signal_notify(sigexitnum_pd()); 394} 395 396 397// --------------------- loading libraries --------------------- 398 399typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 400extern struct JavaVM_ main_vm; 401 402static void* _native_java_library = NULL; 403 404void* 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 */ 447void* 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. 474bool 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 502char *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 510char* 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 523static 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// 539static 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 551void* os::malloc(size_t size, MEMFLAGS flags) { 552 return os::malloc(size, flags, CALLER_PC); 553} 554 555void* 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 625void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 626 return os::realloc(memblock, size, flags, CALLER_PC); 627} 628 629void* 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 683void 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 709void os::init_random(long initval) { 710 _rand_seed = initval; 711} 712 713 714long 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 759void 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 767void os::abort(bool dump_core) { 768 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL); 769} 770 771//--------------------------------------------------------------------------- 772// Helper functions for fatal error handler 773 774void 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 809void 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 824void 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 836void 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 857void 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 898void 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. 1058bool 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 1114extern "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 1149char* 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 1196bool os::set_boot_path(char fileSep, char pathSep) { 1197 const char* home = Arguments::get_java_home(); 1198 int home_len = (int)strlen(home); 1199 1200 struct stat st; 1201 1202 // modular image if "modules" jimage exists 1203 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep); 1204 if (jimage == NULL) return false; 1205 bool has_jimage = (os::stat(jimage, &st) == 0); 1206 if (has_jimage) { 1207 Arguments::set_sysclasspath(jimage); 1208 FREE_C_HEAP_ARRAY(char, jimage); 1209 return true; 1210 } 1211 FREE_C_HEAP_ARRAY(char, jimage); 1212 1213 // check if developer build with exploded modules 1214 char* base_classes = format_boot_path("%/modules/java.base", home, home_len, fileSep, pathSep); 1215 if (base_classes == NULL) return false; 1216 if (os::stat(base_classes, &st) == 0) { 1217 Arguments::set_sysclasspath(base_classes); 1218 FREE_C_HEAP_ARRAY(char, base_classes); 1219 return true; 1220 } 1221 FREE_C_HEAP_ARRAY(char, base_classes); 1222 1223 return false; 1224} 1225 1226/* 1227 * Splits a path, based on its separator, the number of 1228 * elements is returned back in n. 1229 * It is the callers responsibility to: 1230 * a> check the value of n, and n may be 0. 1231 * b> ignore any empty path elements 1232 * c> free up the data. 1233 */ 1234char** os::split_path(const char* path, int* n) { 1235 *n = 0; 1236 if (path == NULL || strlen(path) == 0) { 1237 return NULL; 1238 } 1239 const char psepchar = *os::path_separator(); 1240 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1241 if (inpath == NULL) { 1242 return NULL; 1243 } 1244 strcpy(inpath, path); 1245 int count = 1; 1246 char* p = strchr(inpath, psepchar); 1247 // Get a count of elements to allocate memory 1248 while (p != NULL) { 1249 count++; 1250 p++; 1251 p = strchr(p, psepchar); 1252 } 1253 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1254 if (opath == NULL) { 1255 return NULL; 1256 } 1257 1258 // do the actual splitting 1259 p = inpath; 1260 for (int i = 0 ; i < count ; i++) { 1261 size_t len = strcspn(p, os::path_separator()); 1262 if (len > JVM_MAXPATHLEN) { 1263 return NULL; 1264 } 1265 // allocate the string and add terminator storage 1266 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1267 if (s == NULL) { 1268 return NULL; 1269 } 1270 strncpy(s, p, len); 1271 s[len] = '\0'; 1272 opath[i] = s; 1273 p += len + 1; 1274 } 1275 FREE_C_HEAP_ARRAY(char, inpath); 1276 *n = count; 1277 return opath; 1278} 1279 1280void os::set_memory_serialize_page(address page) { 1281 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1282 _mem_serialize_page = (volatile int32_t *)page; 1283 // We initialize the serialization page shift count here 1284 // We assume a cache line size of 64 bytes 1285 assert(SerializePageShiftCount == count, 1286 "thread size changed, fix SerializePageShiftCount constant"); 1287 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1288} 1289 1290static volatile intptr_t SerializePageLock = 0; 1291 1292// This method is called from signal handler when SIGSEGV occurs while the current 1293// thread tries to store to the "read-only" memory serialize page during state 1294// transition. 1295void os::block_on_serialize_page_trap() { 1296 log_debug(safepoint)("Block until the serialize page permission restored"); 1297 1298 // When VMThread is holding the SerializePageLock during modifying the 1299 // access permission of the memory serialize page, the following call 1300 // will block until the permission of that page is restored to rw. 1301 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1302 // this case, it's OK as the signal is synchronous and we know precisely when 1303 // it can occur. 1304 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1305 Thread::muxRelease(&SerializePageLock); 1306} 1307 1308// Serialize all thread state variables 1309void os::serialize_thread_states() { 1310 // On some platforms such as Solaris & Linux, the time duration of the page 1311 // permission restoration is observed to be much longer than expected due to 1312 // scheduler starvation problem etc. To avoid the long synchronization 1313 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1314 // the mutator thread if such case is encountered. See bug 6546278 for details. 1315 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1316 os::protect_memory((char *)os::get_memory_serialize_page(), 1317 os::vm_page_size(), MEM_PROT_READ); 1318 os::protect_memory((char *)os::get_memory_serialize_page(), 1319 os::vm_page_size(), MEM_PROT_RW); 1320 Thread::muxRelease(&SerializePageLock); 1321} 1322 1323// Returns true if the current stack pointer is above the stack shadow 1324// pages, false otherwise. 1325bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method) { 1326 if (!thread->is_Java_thread()) return false; 1327 address sp = current_stack_pointer(); 1328 // Check if we have StackShadowPages above the yellow zone. This parameter 1329 // is dependent on the depth of the maximum VM call stack possible from 1330 // the handler for stack overflow. 'instanceof' in the stack overflow 1331 // handler or a println uses at least 8k stack of VM and native code 1332 // respectively. 1333 const int framesize_in_bytes = 1334 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1335 1336 assert((thread->stack_base() - thread->stack_size()) + 1337 (JavaThread::stack_guard_zone_size() + 1338 JavaThread::stack_shadow_zone_size() + framesize_in_bytes) == 1339 ((JavaThread*)thread)->stack_overflow_limit() + framesize_in_bytes, "sanity"); 1340 1341 return (sp > ((JavaThread*)thread)->stack_overflow_limit() + framesize_in_bytes); 1342} 1343 1344size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) { 1345 assert(min_pages > 0, "sanity"); 1346 if (UseLargePages) { 1347 const size_t max_page_size = region_size / min_pages; 1348 1349 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1350 const size_t page_size = _page_sizes[i]; 1351 if (page_size <= max_page_size) { 1352 if (!must_be_aligned || is_size_aligned(region_size, page_size)) { 1353 return page_size; 1354 } 1355 } 1356 } 1357 } 1358 1359 return vm_page_size(); 1360} 1361 1362size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) { 1363 return page_size_for_region(region_size, min_pages, true); 1364} 1365 1366size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) { 1367 return page_size_for_region(region_size, min_pages, false); 1368} 1369 1370#ifndef PRODUCT 1371void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1372{ 1373 if (TracePageSizes) { 1374 tty->print("%s: ", str); 1375 for (int i = 0; i < count; ++i) { 1376 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1377 } 1378 tty->cr(); 1379 } 1380} 1381 1382void os::trace_page_sizes(const char* str, const size_t region_min_size, 1383 const size_t region_max_size, const size_t page_size, 1384 const char* base, const size_t size) 1385{ 1386 if (TracePageSizes) { 1387 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1388 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1389 " size=" SIZE_FORMAT, 1390 str, region_min_size, region_max_size, 1391 page_size, p2i(base), size); 1392 } 1393} 1394#endif // #ifndef PRODUCT 1395 1396// This is the working definition of a server class machine: 1397// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1398// because the graphics memory (?) sometimes masks physical memory. 1399// If you want to change the definition of a server class machine 1400// on some OS or platform, e.g., >=4GB on Windows platforms, 1401// then you'll have to parameterize this method based on that state, 1402// as was done for logical processors here, or replicate and 1403// specialize this method for each platform. (Or fix os to have 1404// some inheritance structure and use subclassing. Sigh.) 1405// If you want some platform to always or never behave as a server 1406// class machine, change the setting of AlwaysActAsServerClassMachine 1407// and NeverActAsServerClassMachine in globals*.hpp. 1408bool os::is_server_class_machine() { 1409 // First check for the early returns 1410 if (NeverActAsServerClassMachine) { 1411 return false; 1412 } 1413 if (AlwaysActAsServerClassMachine) { 1414 return true; 1415 } 1416 // Then actually look at the machine 1417 bool result = false; 1418 const unsigned int server_processors = 2; 1419 const julong server_memory = 2UL * G; 1420 // We seem not to get our full complement of memory. 1421 // We allow some part (1/8?) of the memory to be "missing", 1422 // based on the sizes of DIMMs, and maybe graphics cards. 1423 const julong missing_memory = 256UL * M; 1424 1425 /* Is this a server class machine? */ 1426 if ((os::active_processor_count() >= (int)server_processors) && 1427 (os::physical_memory() >= (server_memory - missing_memory))) { 1428 const unsigned int logical_processors = 1429 VM_Version::logical_processors_per_package(); 1430 if (logical_processors > 1) { 1431 const unsigned int physical_packages = 1432 os::active_processor_count() / logical_processors; 1433 if (physical_packages >= server_processors) { 1434 result = true; 1435 } 1436 } else { 1437 result = true; 1438 } 1439 } 1440 return result; 1441} 1442 1443void os::SuspendedThreadTask::run() { 1444 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1445 internal_do_task(); 1446 _done = true; 1447} 1448 1449bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1450 return os::pd_create_stack_guard_pages(addr, bytes); 1451} 1452 1453char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1454 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1455 if (result != NULL) { 1456 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1457 } 1458 1459 return result; 1460} 1461 1462char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1463 MEMFLAGS flags) { 1464 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1465 if (result != NULL) { 1466 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1467 MemTracker::record_virtual_memory_type((address)result, flags); 1468 } 1469 1470 return result; 1471} 1472 1473char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1474 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1475 if (result != NULL) { 1476 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1477 } 1478 return result; 1479} 1480 1481void os::split_reserved_memory(char *base, size_t size, 1482 size_t split, bool realloc) { 1483 pd_split_reserved_memory(base, size, split, realloc); 1484} 1485 1486bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1487 bool res = pd_commit_memory(addr, bytes, executable); 1488 if (res) { 1489 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1490 } 1491 return res; 1492} 1493 1494bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1495 bool executable) { 1496 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1497 if (res) { 1498 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1499 } 1500 return res; 1501} 1502 1503void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1504 const char* mesg) { 1505 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1506 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1507} 1508 1509void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1510 bool executable, const char* mesg) { 1511 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1512 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1513} 1514 1515bool os::uncommit_memory(char* addr, size_t bytes) { 1516 bool res; 1517 if (MemTracker::tracking_level() > NMT_minimal) { 1518 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1519 res = pd_uncommit_memory(addr, bytes); 1520 if (res) { 1521 tkr.record((address)addr, bytes); 1522 } 1523 } else { 1524 res = pd_uncommit_memory(addr, bytes); 1525 } 1526 return res; 1527} 1528 1529bool os::release_memory(char* addr, size_t bytes) { 1530 bool res; 1531 if (MemTracker::tracking_level() > NMT_minimal) { 1532 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1533 res = pd_release_memory(addr, bytes); 1534 if (res) { 1535 tkr.record((address)addr, bytes); 1536 } 1537 } else { 1538 res = pd_release_memory(addr, bytes); 1539 } 1540 return res; 1541} 1542 1543void os::pretouch_memory(char* start, char* end) { 1544 for (volatile char *p = start; p < end; p += os::vm_page_size()) { 1545 *p = 0; 1546 } 1547} 1548 1549char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1550 char *addr, size_t bytes, bool read_only, 1551 bool allow_exec) { 1552 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1553 if (result != NULL) { 1554 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1555 } 1556 return result; 1557} 1558 1559char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1560 char *addr, size_t bytes, bool read_only, 1561 bool allow_exec) { 1562 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1563 read_only, allow_exec); 1564} 1565 1566bool os::unmap_memory(char *addr, size_t bytes) { 1567 bool result; 1568 if (MemTracker::tracking_level() > NMT_minimal) { 1569 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1570 result = pd_unmap_memory(addr, bytes); 1571 if (result) { 1572 tkr.record((address)addr, bytes); 1573 } 1574 } else { 1575 result = pd_unmap_memory(addr, bytes); 1576 } 1577 return result; 1578} 1579 1580void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1581 pd_free_memory(addr, bytes, alignment_hint); 1582} 1583 1584void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1585 pd_realign_memory(addr, bytes, alignment_hint); 1586} 1587 1588#ifndef TARGET_OS_FAMILY_windows 1589/* try to switch state from state "from" to state "to" 1590 * returns the state set after the method is complete 1591 */ 1592os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1593 os::SuspendResume::State to) 1594{ 1595 os::SuspendResume::State result = 1596 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1597 if (result == from) { 1598 // success 1599 return to; 1600 } 1601 return result; 1602} 1603#endif 1604 1605/////////////// Unit tests /////////////// 1606 1607#ifndef PRODUCT 1608 1609#define assert_eq(a,b) assert(a == b, SIZE_FORMAT " != " SIZE_FORMAT, a, b) 1610 1611class TestOS : AllStatic { 1612 static size_t small_page_size() { 1613 return os::vm_page_size(); 1614 } 1615 1616 static size_t large_page_size() { 1617 const size_t large_page_size_example = 4 * M; 1618 return os::page_size_for_region_aligned(large_page_size_example, 1); 1619 } 1620 1621 static void test_page_size_for_region_aligned() { 1622 if (UseLargePages) { 1623 const size_t small_page = small_page_size(); 1624 const size_t large_page = large_page_size(); 1625 1626 if (large_page > small_page) { 1627 size_t num_small_pages_in_large = large_page / small_page; 1628 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large); 1629 1630 assert_eq(page, small_page); 1631 } 1632 } 1633 } 1634 1635 static void test_page_size_for_region_alignment() { 1636 if (UseLargePages) { 1637 const size_t small_page = small_page_size(); 1638 const size_t large_page = large_page_size(); 1639 if (large_page > small_page) { 1640 const size_t unaligned_region = large_page + 17; 1641 size_t page = os::page_size_for_region_aligned(unaligned_region, 1); 1642 assert_eq(page, small_page); 1643 1644 const size_t num_pages = 5; 1645 const size_t aligned_region = large_page * num_pages; 1646 page = os::page_size_for_region_aligned(aligned_region, num_pages); 1647 assert_eq(page, large_page); 1648 } 1649 } 1650 } 1651 1652 static void test_page_size_for_region_unaligned() { 1653 if (UseLargePages) { 1654 // Given exact page size, should return that page size. 1655 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1656 size_t expected = os::_page_sizes[i]; 1657 size_t actual = os::page_size_for_region_unaligned(expected, 1); 1658 assert_eq(expected, actual); 1659 } 1660 1661 // Given slightly larger size than a page size, return the page size. 1662 for (size_t i = 0; os::_page_sizes[i] != 0; i++) { 1663 size_t expected = os::_page_sizes[i]; 1664 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1); 1665 assert_eq(expected, actual); 1666 } 1667 1668 // Given a slightly smaller size than a page size, 1669 // return the next smaller page size. 1670 if (os::_page_sizes[1] > os::_page_sizes[0]) { 1671 size_t expected = os::_page_sizes[0]; 1672 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1); 1673 assert_eq(actual, expected); 1674 } 1675 1676 // Return small page size for values less than a small page. 1677 size_t small_page = small_page_size(); 1678 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1); 1679 assert_eq(small_page, actual); 1680 } 1681 } 1682 1683 public: 1684 static void run_tests() { 1685 test_page_size_for_region_aligned(); 1686 test_page_size_for_region_alignment(); 1687 test_page_size_for_region_unaligned(); 1688 } 1689}; 1690 1691void TestOS_test() { 1692 TestOS::run_tests(); 1693} 1694 1695#endif // PRODUCT 1696