os.cpp revision 5253:8e94527f601e
1/* 2 * Copyright (c) 1997, 2013, 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/icBuffer.hpp" 31#include "code/vtableStubs.hpp" 32#include "gc_implementation/shared/vmGCOperations.hpp" 33#include "interpreter/interpreter.hpp" 34#include "memory/allocation.inline.hpp" 35#include "oops/oop.inline.hpp" 36#include "prims/jvm.h" 37#include "prims/jvm_misc.hpp" 38#include "prims/privilegedStack.hpp" 39#include "runtime/arguments.hpp" 40#include "runtime/frame.inline.hpp" 41#include "runtime/interfaceSupport.hpp" 42#include "runtime/java.hpp" 43#include "runtime/javaCalls.hpp" 44#include "runtime/mutexLocker.hpp" 45#include "runtime/os.hpp" 46#include "runtime/stubRoutines.hpp" 47#include "runtime/thread.inline.hpp" 48#include "services/attachListener.hpp" 49#include "services/memTracker.hpp" 50#include "services/threadService.hpp" 51#include "utilities/defaultStream.hpp" 52#include "utilities/events.hpp" 53#ifdef TARGET_OS_FAMILY_linux 54# include "os_linux.inline.hpp" 55#endif 56#ifdef TARGET_OS_FAMILY_solaris 57# include "os_solaris.inline.hpp" 58#endif 59#ifdef TARGET_OS_FAMILY_windows 60# include "os_windows.inline.hpp" 61#endif 62#ifdef TARGET_OS_FAMILY_bsd 63# include "os_bsd.inline.hpp" 64#endif 65 66# include <signal.h> 67 68OSThread* os::_starting_thread = NULL; 69address os::_polling_page = NULL; 70volatile int32_t* os::_mem_serialize_page = NULL; 71uintptr_t os::_serialize_page_mask = 0; 72long os::_rand_seed = 1; 73int os::_processor_count = 0; 74size_t os::_page_sizes[os::page_sizes_max]; 75 76#ifndef PRODUCT 77julong os::num_mallocs = 0; // # of calls to malloc/realloc 78julong os::alloc_bytes = 0; // # of bytes allocated 79julong os::num_frees = 0; // # of calls to free 80julong os::free_bytes = 0; // # of bytes freed 81#endif 82 83static juint cur_malloc_words = 0; // current size for MallocMaxTestWords 84 85void os_init_globals() { 86 // Called from init_globals(). 87 // See Threads::create_vm() in thread.cpp, and init.cpp. 88 os::init_globals(); 89} 90 91// Fill in buffer with current local time as an ISO-8601 string. 92// E.g., yyyy-mm-ddThh:mm:ss-zzzz. 93// Returns buffer, or NULL if it failed. 94// This would mostly be a call to 95// strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 96// except that on Windows the %z behaves badly, so we do it ourselves. 97// Also, people wanted milliseconds on there, 98// and strftime doesn't do milliseconds. 99char* os::iso8601_time(char* buffer, size_t buffer_length) { 100 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 101 // 1 2 102 // 12345678901234567890123456789 103 static const char* iso8601_format = 104 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; 105 static const size_t needed_buffer = 29; 106 107 // Sanity check the arguments 108 if (buffer == NULL) { 109 assert(false, "NULL buffer"); 110 return NULL; 111 } 112 if (buffer_length < needed_buffer) { 113 assert(false, "buffer_length too small"); 114 return NULL; 115 } 116 // Get the current time 117 jlong milliseconds_since_19700101 = javaTimeMillis(); 118 const int milliseconds_per_microsecond = 1000; 119 const time_t seconds_since_19700101 = 120 milliseconds_since_19700101 / milliseconds_per_microsecond; 121 const int milliseconds_after_second = 122 milliseconds_since_19700101 % milliseconds_per_microsecond; 123 // Convert the time value to a tm and timezone variable 124 struct tm time_struct; 125 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 126 assert(false, "Failed localtime_pd"); 127 return NULL; 128 } 129#if defined(_ALLBSD_SOURCE) 130 const time_t zone = (time_t) time_struct.tm_gmtoff; 131#else 132 const time_t zone = timezone; 133#endif 134 135 // If daylight savings time is in effect, 136 // we are 1 hour East of our time zone 137 const time_t seconds_per_minute = 60; 138 const time_t minutes_per_hour = 60; 139 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 140 time_t UTC_to_local = zone; 141 if (time_struct.tm_isdst > 0) { 142 UTC_to_local = UTC_to_local - seconds_per_hour; 143 } 144 // Compute the time zone offset. 145 // localtime_pd() sets timezone to the difference (in seconds) 146 // between UTC and and local time. 147 // ISO 8601 says we need the difference between local time and UTC, 148 // we change the sign of the localtime_pd() result. 149 const time_t local_to_UTC = -(UTC_to_local); 150 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 151 char sign_local_to_UTC = '+'; 152 time_t abs_local_to_UTC = local_to_UTC; 153 if (local_to_UTC < 0) { 154 sign_local_to_UTC = '-'; 155 abs_local_to_UTC = -(abs_local_to_UTC); 156 } 157 // Convert time zone offset seconds to hours and minutes. 158 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 159 const time_t zone_min = 160 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 161 162 // Print an ISO 8601 date and time stamp into the buffer 163 const int year = 1900 + time_struct.tm_year; 164 const int month = 1 + time_struct.tm_mon; 165 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, 166 year, 167 month, 168 time_struct.tm_mday, 169 time_struct.tm_hour, 170 time_struct.tm_min, 171 time_struct.tm_sec, 172 milliseconds_after_second, 173 sign_local_to_UTC, 174 zone_hours, 175 zone_min); 176 if (printed == 0) { 177 assert(false, "Failed jio_printf"); 178 return NULL; 179 } 180 return buffer; 181} 182 183OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 184#ifdef ASSERT 185 if (!(!thread->is_Java_thread() || 186 Thread::current() == thread || 187 Threads_lock->owned_by_self() 188 || thread->is_Compiler_thread() 189 )) { 190 assert(false, "possibility of dangling Thread pointer"); 191 } 192#endif 193 194 if (p >= MinPriority && p <= MaxPriority) { 195 int priority = java_to_os_priority[p]; 196 return set_native_priority(thread, priority); 197 } else { 198 assert(false, "Should not happen"); 199 return OS_ERR; 200 } 201} 202 203// The mapping from OS priority back to Java priority may be inexact because 204// Java priorities can map M:1 with native priorities. If you want the definite 205// Java priority then use JavaThread::java_priority() 206OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 207 int p; 208 int os_prio; 209 OSReturn ret = get_native_priority(thread, &os_prio); 210 if (ret != OS_OK) return ret; 211 212 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 213 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 214 } else { 215 // niceness values are in reverse order 216 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 217 } 218 priority = (ThreadPriority)p; 219 return OS_OK; 220} 221 222 223// --------------------- sun.misc.Signal (optional) --------------------- 224 225 226// SIGBREAK is sent by the keyboard to query the VM state 227#ifndef SIGBREAK 228#define SIGBREAK SIGQUIT 229#endif 230 231// sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 232 233 234static void signal_thread_entry(JavaThread* thread, TRAPS) { 235 os::set_priority(thread, NearMaxPriority); 236 while (true) { 237 int sig; 238 { 239 // FIXME : Currently we have not decieded what should be the status 240 // for this java thread blocked here. Once we decide about 241 // that we should fix this. 242 sig = os::signal_wait(); 243 } 244 if (sig == os::sigexitnum_pd()) { 245 // Terminate the signal thread 246 return; 247 } 248 249 switch (sig) { 250 case SIGBREAK: { 251 // Check if the signal is a trigger to start the Attach Listener - in that 252 // case don't print stack traces. 253 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 254 continue; 255 } 256 // Print stack traces 257 // Any SIGBREAK operations added here should make sure to flush 258 // the output stream (e.g. tty->flush()) after output. See 4803766. 259 // Each module also prints an extra carriage return after its output. 260 VM_PrintThreads op; 261 VMThread::execute(&op); 262 VM_PrintJNI jni_op; 263 VMThread::execute(&jni_op); 264 VM_FindDeadlocks op1(tty); 265 VMThread::execute(&op1); 266 Universe::print_heap_at_SIGBREAK(); 267 if (PrintClassHistogram) { 268 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */); 269 VMThread::execute(&op1); 270 } 271 if (JvmtiExport::should_post_data_dump()) { 272 JvmtiExport::post_data_dump(); 273 } 274 break; 275 } 276 default: { 277 // Dispatch the signal to java 278 HandleMark hm(THREAD); 279 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 280 KlassHandle klass (THREAD, k); 281 if (klass.not_null()) { 282 JavaValue result(T_VOID); 283 JavaCallArguments args; 284 args.push_int(sig); 285 JavaCalls::call_static( 286 &result, 287 klass, 288 vmSymbols::dispatch_name(), 289 vmSymbols::int_void_signature(), 290 &args, 291 THREAD 292 ); 293 } 294 if (HAS_PENDING_EXCEPTION) { 295 // tty is initialized early so we don't expect it to be null, but 296 // if it is we can't risk doing an initialization that might 297 // trigger additional out-of-memory conditions 298 if (tty != NULL) { 299 char klass_name[256]; 300 char tmp_sig_name[16]; 301 const char* sig_name = "UNKNOWN"; 302 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 303 name()->as_klass_external_name(klass_name, 256); 304 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 305 sig_name = tmp_sig_name; 306 warning("Exception %s occurred dispatching signal %s to handler" 307 "- the VM may need to be forcibly terminated", 308 klass_name, sig_name ); 309 } 310 CLEAR_PENDING_EXCEPTION; 311 } 312 } 313 } 314 } 315} 316 317 318void os::signal_init() { 319 if (!ReduceSignalUsage) { 320 // Setup JavaThread for processing signals 321 EXCEPTION_MARK; 322 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 323 instanceKlassHandle klass (THREAD, k); 324 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 325 326 const char thread_name[] = "Signal Dispatcher"; 327 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 328 329 // Initialize thread_oop to put it into the system threadGroup 330 Handle thread_group (THREAD, Universe::system_thread_group()); 331 JavaValue result(T_VOID); 332 JavaCalls::call_special(&result, thread_oop, 333 klass, 334 vmSymbols::object_initializer_name(), 335 vmSymbols::threadgroup_string_void_signature(), 336 thread_group, 337 string, 338 CHECK); 339 340 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 341 JavaCalls::call_special(&result, 342 thread_group, 343 group, 344 vmSymbols::add_method_name(), 345 vmSymbols::thread_void_signature(), 346 thread_oop, // ARG 1 347 CHECK); 348 349 os::signal_init_pd(); 350 351 { MutexLocker mu(Threads_lock); 352 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 353 354 // At this point it may be possible that no osthread was created for the 355 // JavaThread due to lack of memory. We would have to throw an exception 356 // in that case. However, since this must work and we do not allow 357 // exceptions anyway, check and abort if this fails. 358 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 359 vm_exit_during_initialization("java.lang.OutOfMemoryError", 360 "unable to create new native thread"); 361 } 362 363 java_lang_Thread::set_thread(thread_oop(), signal_thread); 364 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 365 java_lang_Thread::set_daemon(thread_oop()); 366 367 signal_thread->set_threadObj(thread_oop()); 368 Threads::add(signal_thread); 369 Thread::start(signal_thread); 370 } 371 // Handle ^BREAK 372 os::signal(SIGBREAK, os::user_handler()); 373 } 374} 375 376 377void os::terminate_signal_thread() { 378 if (!ReduceSignalUsage) 379 signal_notify(sigexitnum_pd()); 380} 381 382 383// --------------------- loading libraries --------------------- 384 385typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 386extern struct JavaVM_ main_vm; 387 388static void* _native_java_library = NULL; 389 390void* os::native_java_library() { 391 if (_native_java_library == NULL) { 392 char buffer[JVM_MAXPATHLEN]; 393 char ebuf[1024]; 394 395 // Try to load verify dll first. In 1.3 java dll depends on it and is not 396 // always able to find it when the loading executable is outside the JDK. 397 // In order to keep working with 1.2 we ignore any loading errors. 398 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 399 "verify")) { 400 dll_load(buffer, ebuf, sizeof(ebuf)); 401 } 402 403 // Load java dll 404 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 405 "java")) { 406 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 407 } 408 if (_native_java_library == NULL) { 409 vm_exit_during_initialization("Unable to load native library", ebuf); 410 } 411 412#if defined(__OpenBSD__) 413 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 414 // ignore errors 415 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 416 "net")) { 417 dll_load(buffer, ebuf, sizeof(ebuf)); 418 } 419#endif 420 } 421 static jboolean onLoaded = JNI_FALSE; 422 if (onLoaded) { 423 // We may have to wait to fire OnLoad until TLS is initialized. 424 if (ThreadLocalStorage::is_initialized()) { 425 // The JNI_OnLoad handling is normally done by method load in 426 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 427 // explicitly so we have to check for JNI_OnLoad as well 428 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 429 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 430 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 431 if (JNI_OnLoad != NULL) { 432 JavaThread* thread = JavaThread::current(); 433 ThreadToNativeFromVM ttn(thread); 434 HandleMark hm(thread); 435 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 436 onLoaded = JNI_TRUE; 437 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 438 vm_exit_during_initialization("Unsupported JNI version"); 439 } 440 } 441 } 442 } 443 return _native_java_library; 444} 445 446/* 447 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 448 * If check_lib == true then we are looking for an 449 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 450 * this library is statically linked into the image. 451 * If check_lib == false then we will look for the appropriate symbol in the 452 * executable if agent_lib->is_static_lib() == true or in the shared library 453 * referenced by 'handle'. 454 */ 455void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 456 const char *syms[], size_t syms_len) { 457 assert(agent_lib != NULL, "sanity check"); 458 const char *lib_name; 459 void *handle = agent_lib->os_lib(); 460 void *entryName = NULL; 461 char *agent_function_name; 462 size_t i; 463 464 // If checking then use the agent name otherwise test is_static_lib() to 465 // see how to process this lookup 466 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 467 for (i = 0; i < syms_len; i++) { 468 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 469 if (agent_function_name == NULL) { 470 break; 471 } 472 entryName = dll_lookup(handle, agent_function_name); 473 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread); 474 if (entryName != NULL) { 475 break; 476 } 477 } 478 return entryName; 479} 480 481// See if the passed in agent is statically linked into the VM image. 482bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 483 size_t syms_len) { 484 void *ret; 485 void *proc_handle; 486 void *save_handle; 487 488 assert(agent_lib != NULL, "sanity check"); 489 if (agent_lib->name() == NULL) { 490 return false; 491 } 492 proc_handle = get_default_process_handle(); 493 // Check for Agent_OnLoad/Attach_lib_name function 494 save_handle = agent_lib->os_lib(); 495 // We want to look in this process' symbol table. 496 agent_lib->set_os_lib(proc_handle); 497 ret = find_agent_function(agent_lib, true, syms, syms_len); 498 if (ret != NULL) { 499 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 500 agent_lib->set_valid(); 501 agent_lib->set_static_lib(true); 502 return true; 503 } 504 agent_lib->set_os_lib(save_handle); 505 return false; 506} 507 508// --------------------- heap allocation utilities --------------------- 509 510char *os::strdup(const char *str, MEMFLAGS flags) { 511 size_t size = strlen(str); 512 char *dup_str = (char *)malloc(size + 1, flags); 513 if (dup_str == NULL) return NULL; 514 strcpy(dup_str, str); 515 return dup_str; 516} 517 518 519 520#ifdef ASSERT 521#define space_before (MallocCushion + sizeof(double)) 522#define space_after MallocCushion 523#define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) 524#define size_addr_from_obj(p) ((size_t*)p - 1) 525// MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly 526// NB: cannot be debug variable, because these aren't set from the command line until 527// *after* the first few allocs already happened 528#define MallocCushion 16 529#else 530#define space_before 0 531#define space_after 0 532#define size_addr_from_base(p) should not use w/o ASSERT 533#define size_addr_from_obj(p) should not use w/o ASSERT 534#define MallocCushion 0 535#endif 536#define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 537 538#ifdef ASSERT 539inline size_t get_size(void* obj) { 540 size_t size = *size_addr_from_obj(obj); 541 if (size < 0) { 542 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten (" 543 SIZE_FORMAT ")", obj, size)); 544 } 545 return size; 546} 547 548u_char* find_cushion_backwards(u_char* start) { 549 u_char* p = start; 550 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || 551 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; 552 // ok, we have four consecutive marker bytes; find start 553 u_char* q = p - 4; 554 while (*q == badResourceValue) q--; 555 return q + 1; 556} 557 558u_char* find_cushion_forwards(u_char* start) { 559 u_char* p = start; 560 while (p[0] != badResourceValue || p[1] != badResourceValue || 561 p[2] != badResourceValue || p[3] != badResourceValue) p++; 562 // ok, we have four consecutive marker bytes; find end of cushion 563 u_char* q = p + 4; 564 while (*q == badResourceValue) q++; 565 return q - MallocCushion; 566} 567 568void print_neighbor_blocks(void* ptr) { 569 // find block allocated before ptr (not entirely crash-proof) 570 if (MallocCushion < 4) { 571 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); 572 return; 573 } 574 u_char* start_of_this_block = (u_char*)ptr - space_before; 575 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; 576 // look for cushion in front of prev. block 577 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); 578 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); 579 u_char* obj = start_of_prev_block + space_before; 580 if (size <= 0 ) { 581 // start is bad; mayhave been confused by OS data inbetween objects 582 // search one more backwards 583 start_of_prev_block = find_cushion_backwards(start_of_prev_block); 584 size = *size_addr_from_base(start_of_prev_block); 585 obj = start_of_prev_block + space_before; 586 } 587 588 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { 589 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 590 } else { 591 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 592 } 593 594 // now find successor block 595 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; 596 start_of_next_block = find_cushion_forwards(start_of_next_block); 597 u_char* next_obj = start_of_next_block + space_before; 598 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); 599 if (start_of_next_block[0] == badResourceValue && 600 start_of_next_block[1] == badResourceValue && 601 start_of_next_block[2] == badResourceValue && 602 start_of_next_block[3] == badResourceValue) { 603 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 604 } else { 605 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 606 } 607} 608 609 610void report_heap_error(void* memblock, void* bad, const char* where) { 611 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 612 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock); 613 print_neighbor_blocks(memblock); 614 fatal("memory stomping error"); 615} 616 617void verify_block(void* memblock) { 618 size_t size = get_size(memblock); 619 if (MallocCushion) { 620 u_char* ptr = (u_char*)memblock - space_before; 621 for (int i = 0; i < MallocCushion; i++) { 622 if (ptr[i] != badResourceValue) { 623 report_heap_error(memblock, ptr+i, "in front of"); 624 } 625 } 626 u_char* end = (u_char*)memblock + size + space_after; 627 for (int j = -MallocCushion; j < 0; j++) { 628 if (end[j] != badResourceValue) { 629 report_heap_error(memblock, end+j, "after"); 630 } 631 } 632 } 633} 634#endif 635 636// 637// This function supports testing of the malloc out of memory 638// condition without really running the system out of memory. 639// 640static u_char* testMalloc(size_t alloc_size) { 641 assert(MallocMaxTestWords > 0, "sanity check"); 642 643 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 644 return NULL; 645 } 646 647 u_char* ptr = (u_char*)::malloc(alloc_size); 648 649 if (ptr != NULL) { 650 Atomic::add(((jint) (alloc_size / BytesPerWord)), 651 (volatile jint *) &cur_malloc_words); 652 } 653 return ptr; 654} 655 656void* os::malloc(size_t size, MEMFLAGS memflags, address caller) { 657 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 658 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 659 660#ifdef ASSERT 661 // checking for the WatcherThread and crash_protection first 662 // since os::malloc can be called when the libjvm.{dll,so} is 663 // first loaded and we don't have a thread yet. 664 // try to find the thread after we see that the watcher thread 665 // exists and has crash protection. 666 WatcherThread *wt = WatcherThread::watcher_thread(); 667 if (wt != NULL && wt->has_crash_protection()) { 668 Thread* thread = ThreadLocalStorage::get_thread_slow(); 669 if (thread == wt) { 670 assert(!wt->has_crash_protection(), 671 "Can't malloc with crash protection from WatcherThread"); 672 } 673 } 674#endif 675 676 if (size == 0) { 677 // return a valid pointer if size is zero 678 // if NULL is returned the calling functions assume out of memory. 679 size = 1; 680 } 681 682 const size_t alloc_size = size + space_before + space_after; 683 684 if (size > alloc_size) { // Check for rollover. 685 return NULL; 686 } 687 688 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 689 690 u_char* ptr; 691 692 if (MallocMaxTestWords > 0) { 693 ptr = testMalloc(alloc_size); 694 } else { 695 ptr = (u_char*)::malloc(alloc_size); 696 } 697 698#ifdef ASSERT 699 if (ptr == NULL) return NULL; 700 if (MallocCushion) { 701 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; 702 u_char* end = ptr + space_before + size; 703 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; 704 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; 705 } 706 // put size just before data 707 *size_addr_from_base(ptr) = size; 708#endif 709 u_char* memblock = ptr + space_before; 710 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 711 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 712 breakpoint(); 713 } 714 debug_only(if (paranoid) verify_block(memblock)); 715 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 716 717 // we do not track MallocCushion memory 718 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller); 719 720 return memblock; 721} 722 723 724void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) { 725#ifndef ASSERT 726 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 727 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 728 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker(); 729 void* ptr = ::realloc(memblock, size); 730 if (ptr != NULL) { 731 tkr.record((address)memblock, (address)ptr, size, memflags, 732 caller == 0 ? CALLER_PC : caller); 733 } else { 734 tkr.discard(); 735 } 736 return ptr; 737#else 738 if (memblock == NULL) { 739 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller)); 740 } 741 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 742 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 743 breakpoint(); 744 } 745 verify_block(memblock); 746 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 747 if (size == 0) return NULL; 748 // always move the block 749 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller); 750 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 751 // Copy to new memory if malloc didn't fail 752 if ( ptr != NULL ) { 753 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); 754 if (paranoid) verify_block(ptr); 755 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 756 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 757 breakpoint(); 758 } 759 free(memblock); 760 } 761 return ptr; 762#endif 763} 764 765 766void os::free(void *memblock, MEMFLAGS memflags) { 767 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 768#ifdef ASSERT 769 if (memblock == NULL) return; 770 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 771 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 772 breakpoint(); 773 } 774 verify_block(memblock); 775 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 776 // Added by detlefs. 777 if (MallocCushion) { 778 u_char* ptr = (u_char*)memblock - space_before; 779 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { 780 guarantee(*p == badResourceValue, 781 "Thing freed should be malloc result."); 782 *p = (u_char)freeBlockPad; 783 } 784 size_t size = get_size(memblock); 785 inc_stat_counter(&free_bytes, size); 786 u_char* end = ptr + space_before + size; 787 for (u_char* q = end; q < end + MallocCushion; q++) { 788 guarantee(*q == badResourceValue, 789 "Thing freed should be malloc result."); 790 *q = (u_char)freeBlockPad; 791 } 792 if (PrintMalloc && tty != NULL) 793 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 794 } else if (PrintMalloc && tty != NULL) { 795 // tty->print_cr("os::free %p", memblock); 796 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock); 797 } 798#endif 799 MemTracker::record_free((address)memblock, memflags); 800 801 ::free((char*)memblock - space_before); 802} 803 804void os::init_random(long initval) { 805 _rand_seed = initval; 806} 807 808 809long os::random() { 810 /* standard, well-known linear congruential random generator with 811 * next_rand = (16807*seed) mod (2**31-1) 812 * see 813 * (1) "Random Number Generators: Good Ones Are Hard to Find", 814 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 815 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 816 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 817 */ 818 const long a = 16807; 819 const unsigned long m = 2147483647; 820 const long q = m / a; assert(q == 127773, "weird math"); 821 const long r = m % a; assert(r == 2836, "weird math"); 822 823 // compute az=2^31p+q 824 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 825 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 826 lo += (hi & 0x7FFF) << 16; 827 828 // if q overflowed, ignore the overflow and increment q 829 if (lo > m) { 830 lo &= m; 831 ++lo; 832 } 833 lo += hi >> 15; 834 835 // if (p+q) overflowed, ignore the overflow and increment (p+q) 836 if (lo > m) { 837 lo &= m; 838 ++lo; 839 } 840 return (_rand_seed = lo); 841} 842 843// The INITIALIZED state is distinguished from the SUSPENDED state because the 844// conditions in which a thread is first started are different from those in which 845// a suspension is resumed. These differences make it hard for us to apply the 846// tougher checks when starting threads that we want to do when resuming them. 847// However, when start_thread is called as a result of Thread.start, on a Java 848// thread, the operation is synchronized on the Java Thread object. So there 849// cannot be a race to start the thread and hence for the thread to exit while 850// we are working on it. Non-Java threads that start Java threads either have 851// to do so in a context in which races are impossible, or should do appropriate 852// locking. 853 854void os::start_thread(Thread* thread) { 855 // guard suspend/resume 856 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 857 OSThread* osthread = thread->osthread(); 858 osthread->set_state(RUNNABLE); 859 pd_start_thread(thread); 860} 861 862//--------------------------------------------------------------------------- 863// Helper functions for fatal error handler 864 865void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 866 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 867 868 int cols = 0; 869 int cols_per_line = 0; 870 switch (unitsize) { 871 case 1: cols_per_line = 16; break; 872 case 2: cols_per_line = 8; break; 873 case 4: cols_per_line = 4; break; 874 case 8: cols_per_line = 2; break; 875 default: return; 876 } 877 878 address p = start; 879 st->print(PTR_FORMAT ": ", start); 880 while (p < end) { 881 switch (unitsize) { 882 case 1: st->print("%02x", *(u1*)p); break; 883 case 2: st->print("%04x", *(u2*)p); break; 884 case 4: st->print("%08x", *(u4*)p); break; 885 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 886 } 887 p += unitsize; 888 cols++; 889 if (cols >= cols_per_line && p < end) { 890 cols = 0; 891 st->cr(); 892 st->print(PTR_FORMAT ": ", p); 893 } else { 894 st->print(" "); 895 } 896 } 897 st->cr(); 898} 899 900void os::print_environment_variables(outputStream* st, const char** env_list, 901 char* buffer, int len) { 902 if (env_list) { 903 st->print_cr("Environment Variables:"); 904 905 for (int i = 0; env_list[i] != NULL; i++) { 906 if (getenv(env_list[i], buffer, len)) { 907 st->print(env_list[i]); 908 st->print("="); 909 st->print_cr(buffer); 910 } 911 } 912 } 913} 914 915void os::print_cpu_info(outputStream* st) { 916 // cpu 917 st->print("CPU:"); 918 st->print("total %d", os::processor_count()); 919 // It's not safe to query number of active processors after crash 920 // st->print("(active %d)", os::active_processor_count()); 921 st->print(" %s", VM_Version::cpu_features()); 922 st->cr(); 923 pd_print_cpu_info(st); 924} 925 926void os::print_date_and_time(outputStream *st) { 927 time_t tloc; 928 (void)time(&tloc); 929 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 930 931 double t = os::elapsedTime(); 932 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 933 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 934 // before printf. We lost some precision, but who cares? 935 st->print_cr("elapsed time: %d seconds", (int)t); 936} 937 938// moved from debug.cpp (used to be find()) but still called from there 939// The verbose parameter is only set by the debug code in one case 940void os::print_location(outputStream* st, intptr_t x, bool verbose) { 941 address addr = (address)x; 942 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 943 if (b != NULL) { 944 if (b->is_buffer_blob()) { 945 // the interpreter is generated into a buffer blob 946 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 947 if (i != NULL) { 948 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 949 i->print_on(st); 950 return; 951 } 952 if (Interpreter::contains(addr)) { 953 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 954 " (not bytecode specific)", addr); 955 return; 956 } 957 // 958 if (AdapterHandlerLibrary::contains(b)) { 959 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 960 AdapterHandlerLibrary::print_handler_on(st, b); 961 } 962 // the stubroutines are generated into a buffer blob 963 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 964 if (d != NULL) { 965 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 966 d->print_on(st); 967 st->cr(); 968 return; 969 } 970 if (StubRoutines::contains(addr)) { 971 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 972 "stub routine", addr); 973 return; 974 } 975 // the InlineCacheBuffer is using stubs generated into a buffer blob 976 if (InlineCacheBuffer::contains(addr)) { 977 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 978 return; 979 } 980 VtableStub* v = VtableStubs::stub_containing(addr); 981 if (v != NULL) { 982 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 983 v->print_on(st); 984 st->cr(); 985 return; 986 } 987 } 988 nmethod* nm = b->as_nmethod_or_null(); 989 if (nm != NULL) { 990 ResourceMark rm; 991 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 992 addr, (int)(addr - nm->entry_point()), nm); 993 if (verbose) { 994 st->print(" for "); 995 nm->method()->print_value_on(st); 996 } 997 st->cr(); 998 nm->print_nmethod(verbose); 999 return; 1000 } 1001 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 1002 b->print_on(st); 1003 return; 1004 } 1005 1006 if (Universe::heap()->is_in(addr)) { 1007 HeapWord* p = Universe::heap()->block_start(addr); 1008 bool print = false; 1009 // If we couldn't find it it just may mean that heap wasn't parseable 1010 // See if we were just given an oop directly 1011 if (p != NULL && Universe::heap()->block_is_obj(p)) { 1012 print = true; 1013 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 1014 p = (HeapWord*) addr; 1015 print = true; 1016 } 1017 if (print) { 1018 if (p == (HeapWord*) addr) { 1019 st->print_cr(INTPTR_FORMAT " is an oop", addr); 1020 } else { 1021 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 1022 } 1023 oop(p)->print_on(st); 1024 return; 1025 } 1026 } else { 1027 if (Universe::heap()->is_in_reserved(addr)) { 1028 st->print_cr(INTPTR_FORMAT " is an unallocated location " 1029 "in the heap", addr); 1030 return; 1031 } 1032 } 1033 if (JNIHandles::is_global_handle((jobject) addr)) { 1034 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 1035 return; 1036 } 1037 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 1038 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 1039 return; 1040 } 1041#ifndef PRODUCT 1042 // we don't keep the block list in product mode 1043 if (JNIHandleBlock::any_contains((jobject) addr)) { 1044 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 1045 return; 1046 } 1047#endif 1048 1049 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1050 // Check for privilege stack 1051 if (thread->privileged_stack_top() != NULL && 1052 thread->privileged_stack_top()->contains(addr)) { 1053 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1054 "for thread: " INTPTR_FORMAT, addr, thread); 1055 if (verbose) thread->print_on(st); 1056 return; 1057 } 1058 // If the addr is a java thread print information about that. 1059 if (addr == (address)thread) { 1060 if (verbose) { 1061 thread->print_on(st); 1062 } else { 1063 st->print_cr(INTPTR_FORMAT " is a thread", addr); 1064 } 1065 return; 1066 } 1067 // If the addr is in the stack region for this thread then report that 1068 // and print thread info 1069 if (thread->stack_base() >= addr && 1070 addr > (thread->stack_base() - thread->stack_size())) { 1071 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1072 INTPTR_FORMAT, addr, thread); 1073 if (verbose) thread->print_on(st); 1074 return; 1075 } 1076 1077 } 1078 1079#ifndef PRODUCT 1080 // Check if in metaspace. 1081 if (ClassLoaderDataGraph::contains((address)addr)) { 1082 // Use addr->print() from the debugger instead (not here) 1083 st->print_cr(INTPTR_FORMAT 1084 " is pointing into metadata", addr); 1085 return; 1086 } 1087#endif 1088 1089 // Try an OS specific find 1090 if (os::find(addr, st)) { 1091 return; 1092 } 1093 1094 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1095} 1096 1097// Looks like all platforms except IA64 can use the same function to check 1098// if C stack is walkable beyond current frame. The check for fp() is not 1099// necessary on Sparc, but it's harmless. 1100bool os::is_first_C_frame(frame* fr) { 1101#if defined(IA64) && !defined(_WIN32) 1102 // On IA64 we have to check if the callers bsp is still valid 1103 // (i.e. within the register stack bounds). 1104 // Notice: this only works for threads created by the VM and only if 1105 // we walk the current stack!!! If we want to be able to walk 1106 // arbitrary other threads, we'll have to somehow store the thread 1107 // object in the frame. 1108 Thread *thread = Thread::current(); 1109 if ((address)fr->fp() <= 1110 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1111 // This check is a little hacky, because on Linux the first C 1112 // frame's ('start_thread') register stack frame starts at 1113 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1114 // ('__pthread_bound_body') register stack frame seems to really 1115 // start at "register_stack_base". 1116 return true; 1117 } else { 1118 return false; 1119 } 1120#elif defined(IA64) && defined(_WIN32) 1121 return true; 1122#else 1123 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1124 // Check usp first, because if that's bad the other accessors may fault 1125 // on some architectures. Ditto ufp second, etc. 1126 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1127 // sp on amd can be 32 bit aligned. 1128 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1129 1130 uintptr_t usp = (uintptr_t)fr->sp(); 1131 if ((usp & sp_align_mask) != 0) return true; 1132 1133 uintptr_t ufp = (uintptr_t)fr->fp(); 1134 if ((ufp & fp_align_mask) != 0) return true; 1135 1136 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1137 if ((old_sp & sp_align_mask) != 0) return true; 1138 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1139 1140 uintptr_t old_fp = (uintptr_t)fr->link(); 1141 if ((old_fp & fp_align_mask) != 0) return true; 1142 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1143 1144 // stack grows downwards; if old_fp is below current fp or if the stack 1145 // frame is too large, either the stack is corrupted or fp is not saved 1146 // on stack (i.e. on x86, ebp may be used as general register). The stack 1147 // is not walkable beyond current frame. 1148 if (old_fp < ufp) return true; 1149 if (old_fp - ufp > 64 * K) return true; 1150 1151 return false; 1152#endif 1153} 1154 1155#ifdef ASSERT 1156extern "C" void test_random() { 1157 const double m = 2147483647; 1158 double mean = 0.0, variance = 0.0, t; 1159 long reps = 10000; 1160 unsigned long seed = 1; 1161 1162 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1163 os::init_random(seed); 1164 long num; 1165 for (int k = 0; k < reps; k++) { 1166 num = os::random(); 1167 double u = (double)num / m; 1168 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1169 1170 // calculate mean and variance of the random sequence 1171 mean += u; 1172 variance += (u*u); 1173 } 1174 mean /= reps; 1175 variance /= (reps - 1); 1176 1177 assert(num == 1043618065, "bad seed"); 1178 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1179 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1180 const double eps = 0.0001; 1181 t = fabsd(mean - 0.5018); 1182 assert(t < eps, "bad mean"); 1183 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1184 assert(t < eps, "bad variance"); 1185} 1186#endif 1187 1188 1189// Set up the boot classpath. 1190 1191char* os::format_boot_path(const char* format_string, 1192 const char* home, 1193 int home_len, 1194 char fileSep, 1195 char pathSep) { 1196 assert((fileSep == '/' && pathSep == ':') || 1197 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1198 1199 // Scan the format string to determine the length of the actual 1200 // boot classpath, and handle platform dependencies as well. 1201 int formatted_path_len = 0; 1202 const char* p; 1203 for (p = format_string; *p != 0; ++p) { 1204 if (*p == '%') formatted_path_len += home_len - 1; 1205 ++formatted_path_len; 1206 } 1207 1208 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1209 if (formatted_path == NULL) { 1210 return NULL; 1211 } 1212 1213 // Create boot classpath from format, substituting separator chars and 1214 // java home directory. 1215 char* q = formatted_path; 1216 for (p = format_string; *p != 0; ++p) { 1217 switch (*p) { 1218 case '%': 1219 strcpy(q, home); 1220 q += home_len; 1221 break; 1222 case '/': 1223 *q++ = fileSep; 1224 break; 1225 case ':': 1226 *q++ = pathSep; 1227 break; 1228 default: 1229 *q++ = *p; 1230 } 1231 } 1232 *q = '\0'; 1233 1234 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1235 return formatted_path; 1236} 1237 1238 1239bool os::set_boot_path(char fileSep, char pathSep) { 1240 const char* home = Arguments::get_java_home(); 1241 int home_len = (int)strlen(home); 1242 1243 static const char* meta_index_dir_format = "%/lib/"; 1244 static const char* meta_index_format = "%/lib/meta-index"; 1245 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1246 if (meta_index == NULL) return false; 1247 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1248 if (meta_index_dir == NULL) return false; 1249 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1250 1251 // Any modification to the JAR-file list, for the boot classpath must be 1252 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1253 // path class JARs, are stripped for StackMapTable to reduce download size. 1254 static const char classpath_format[] = 1255 "%/lib/resources.jar:" 1256 "%/lib/rt.jar:" 1257 "%/lib/sunrsasign.jar:" 1258 "%/lib/jsse.jar:" 1259 "%/lib/jce.jar:" 1260 "%/lib/charsets.jar:" 1261 "%/lib/jfr.jar:" 1262#ifdef __APPLE__ 1263 "%/lib/JObjC.jar:" 1264#endif 1265 "%/classes"; 1266 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1267 if (sysclasspath == NULL) return false; 1268 Arguments::set_sysclasspath(sysclasspath); 1269 1270 return true; 1271} 1272 1273/* 1274 * Splits a path, based on its separator, the number of 1275 * elements is returned back in n. 1276 * It is the callers responsibility to: 1277 * a> check the value of n, and n may be 0. 1278 * b> ignore any empty path elements 1279 * c> free up the data. 1280 */ 1281char** os::split_path(const char* path, int* n) { 1282 *n = 0; 1283 if (path == NULL || strlen(path) == 0) { 1284 return NULL; 1285 } 1286 const char psepchar = *os::path_separator(); 1287 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1288 if (inpath == NULL) { 1289 return NULL; 1290 } 1291 strcpy(inpath, path); 1292 int count = 1; 1293 char* p = strchr(inpath, psepchar); 1294 // Get a count of elements to allocate memory 1295 while (p != NULL) { 1296 count++; 1297 p++; 1298 p = strchr(p, psepchar); 1299 } 1300 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1301 if (opath == NULL) { 1302 return NULL; 1303 } 1304 1305 // do the actual splitting 1306 p = inpath; 1307 for (int i = 0 ; i < count ; i++) { 1308 size_t len = strcspn(p, os::path_separator()); 1309 if (len > JVM_MAXPATHLEN) { 1310 return NULL; 1311 } 1312 // allocate the string and add terminator storage 1313 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1314 if (s == NULL) { 1315 return NULL; 1316 } 1317 strncpy(s, p, len); 1318 s[len] = '\0'; 1319 opath[i] = s; 1320 p += len + 1; 1321 } 1322 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1323 *n = count; 1324 return opath; 1325} 1326 1327void os::set_memory_serialize_page(address page) { 1328 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1329 _mem_serialize_page = (volatile int32_t *)page; 1330 // We initialize the serialization page shift count here 1331 // We assume a cache line size of 64 bytes 1332 assert(SerializePageShiftCount == count, 1333 "thread size changed, fix SerializePageShiftCount constant"); 1334 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1335} 1336 1337static volatile intptr_t SerializePageLock = 0; 1338 1339// This method is called from signal handler when SIGSEGV occurs while the current 1340// thread tries to store to the "read-only" memory serialize page during state 1341// transition. 1342void os::block_on_serialize_page_trap() { 1343 if (TraceSafepoint) { 1344 tty->print_cr("Block until the serialize page permission restored"); 1345 } 1346 // When VMThread is holding the SerializePageLock during modifying the 1347 // access permission of the memory serialize page, the following call 1348 // will block until the permission of that page is restored to rw. 1349 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1350 // this case, it's OK as the signal is synchronous and we know precisely when 1351 // it can occur. 1352 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1353 Thread::muxRelease(&SerializePageLock); 1354} 1355 1356// Serialize all thread state variables 1357void os::serialize_thread_states() { 1358 // On some platforms such as Solaris & Linux, the time duration of the page 1359 // permission restoration is observed to be much longer than expected due to 1360 // scheduler starvation problem etc. To avoid the long synchronization 1361 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1362 // the mutator thread if such case is encountered. See bug 6546278 for details. 1363 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1364 os::protect_memory((char *)os::get_memory_serialize_page(), 1365 os::vm_page_size(), MEM_PROT_READ); 1366 os::protect_memory((char *)os::get_memory_serialize_page(), 1367 os::vm_page_size(), MEM_PROT_RW); 1368 Thread::muxRelease(&SerializePageLock); 1369} 1370 1371// Returns true if the current stack pointer is above the stack shadow 1372// pages, false otherwise. 1373 1374bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1375 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1376 address sp = current_stack_pointer(); 1377 // Check if we have StackShadowPages above the yellow zone. This parameter 1378 // is dependent on the depth of the maximum VM call stack possible from 1379 // the handler for stack overflow. 'instanceof' in the stack overflow 1380 // handler or a println uses at least 8k stack of VM and native code 1381 // respectively. 1382 const int framesize_in_bytes = 1383 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1384 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1385 * vm_page_size()) + framesize_in_bytes; 1386 // The very lower end of the stack 1387 address stack_limit = thread->stack_base() - thread->stack_size(); 1388 return (sp > (stack_limit + reserved_area)); 1389} 1390 1391size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1392 uint min_pages) 1393{ 1394 assert(min_pages > 0, "sanity"); 1395 if (UseLargePages) { 1396 const size_t max_page_size = region_max_size / min_pages; 1397 1398 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1399 const size_t sz = _page_sizes[i]; 1400 const size_t mask = sz - 1; 1401 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1402 // The largest page size with no fragmentation. 1403 return sz; 1404 } 1405 1406 if (sz <= max_page_size) { 1407 // The largest page size that satisfies the min_pages requirement. 1408 return sz; 1409 } 1410 } 1411 } 1412 1413 return vm_page_size(); 1414} 1415 1416#ifndef PRODUCT 1417void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1418{ 1419 if (TracePageSizes) { 1420 tty->print("%s: ", str); 1421 for (int i = 0; i < count; ++i) { 1422 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1423 } 1424 tty->cr(); 1425 } 1426} 1427 1428void os::trace_page_sizes(const char* str, const size_t region_min_size, 1429 const size_t region_max_size, const size_t page_size, 1430 const char* base, const size_t size) 1431{ 1432 if (TracePageSizes) { 1433 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1434 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1435 " size=" SIZE_FORMAT, 1436 str, region_min_size, region_max_size, 1437 page_size, base, size); 1438 } 1439} 1440#endif // #ifndef PRODUCT 1441 1442// This is the working definition of a server class machine: 1443// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1444// because the graphics memory (?) sometimes masks physical memory. 1445// If you want to change the definition of a server class machine 1446// on some OS or platform, e.g., >=4GB on Windohs platforms, 1447// then you'll have to parameterize this method based on that state, 1448// as was done for logical processors here, or replicate and 1449// specialize this method for each platform. (Or fix os to have 1450// some inheritance structure and use subclassing. Sigh.) 1451// If you want some platform to always or never behave as a server 1452// class machine, change the setting of AlwaysActAsServerClassMachine 1453// and NeverActAsServerClassMachine in globals*.hpp. 1454bool os::is_server_class_machine() { 1455 // First check for the early returns 1456 if (NeverActAsServerClassMachine) { 1457 return false; 1458 } 1459 if (AlwaysActAsServerClassMachine) { 1460 return true; 1461 } 1462 // Then actually look at the machine 1463 bool result = false; 1464 const unsigned int server_processors = 2; 1465 const julong server_memory = 2UL * G; 1466 // We seem not to get our full complement of memory. 1467 // We allow some part (1/8?) of the memory to be "missing", 1468 // based on the sizes of DIMMs, and maybe graphics cards. 1469 const julong missing_memory = 256UL * M; 1470 1471 /* Is this a server class machine? */ 1472 if ((os::active_processor_count() >= (int)server_processors) && 1473 (os::physical_memory() >= (server_memory - missing_memory))) { 1474 const unsigned int logical_processors = 1475 VM_Version::logical_processors_per_package(); 1476 if (logical_processors > 1) { 1477 const unsigned int physical_packages = 1478 os::active_processor_count() / logical_processors; 1479 if (physical_packages > server_processors) { 1480 result = true; 1481 } 1482 } else { 1483 result = true; 1484 } 1485 } 1486 return result; 1487} 1488 1489void os::SuspendedThreadTask::run() { 1490 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1491 internal_do_task(); 1492 _done = true; 1493} 1494 1495bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1496 return os::pd_create_stack_guard_pages(addr, bytes); 1497} 1498 1499char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1500 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1501 if (result != NULL) { 1502 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1503 } 1504 1505 return result; 1506} 1507 1508char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1509 MEMFLAGS flags) { 1510 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1511 if (result != NULL) { 1512 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1513 MemTracker::record_virtual_memory_type((address)result, flags); 1514 } 1515 1516 return result; 1517} 1518 1519char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1520 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1521 if (result != NULL) { 1522 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1523 } 1524 return result; 1525} 1526 1527void os::split_reserved_memory(char *base, size_t size, 1528 size_t split, bool realloc) { 1529 pd_split_reserved_memory(base, size, split, realloc); 1530} 1531 1532bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1533 bool res = pd_commit_memory(addr, bytes, executable); 1534 if (res) { 1535 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1536 } 1537 return res; 1538} 1539 1540bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1541 bool executable) { 1542 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1543 if (res) { 1544 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1545 } 1546 return res; 1547} 1548 1549void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1550 const char* mesg) { 1551 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1552 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1553} 1554 1555void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1556 bool executable, const char* mesg) { 1557 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1558 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1559} 1560 1561bool os::uncommit_memory(char* addr, size_t bytes) { 1562 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1563 bool res = pd_uncommit_memory(addr, bytes); 1564 if (res) { 1565 tkr.record((address)addr, bytes); 1566 } else { 1567 tkr.discard(); 1568 } 1569 return res; 1570} 1571 1572bool os::release_memory(char* addr, size_t bytes) { 1573 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1574 bool res = pd_release_memory(addr, bytes); 1575 if (res) { 1576 tkr.record((address)addr, bytes); 1577 } else { 1578 tkr.discard(); 1579 } 1580 return res; 1581} 1582 1583 1584char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1585 char *addr, size_t bytes, bool read_only, 1586 bool allow_exec) { 1587 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1588 if (result != NULL) { 1589 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC); 1590 } 1591 return result; 1592} 1593 1594char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1595 char *addr, size_t bytes, bool read_only, 1596 bool allow_exec) { 1597 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1598 read_only, allow_exec); 1599} 1600 1601bool os::unmap_memory(char *addr, size_t bytes) { 1602 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1603 bool result = pd_unmap_memory(addr, bytes); 1604 if (result) { 1605 tkr.record((address)addr, bytes); 1606 } else { 1607 tkr.discard(); 1608 } 1609 return result; 1610} 1611 1612void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1613 pd_free_memory(addr, bytes, alignment_hint); 1614} 1615 1616void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1617 pd_realign_memory(addr, bytes, alignment_hint); 1618} 1619 1620#ifndef TARGET_OS_FAMILY_windows 1621/* try to switch state from state "from" to state "to" 1622 * returns the state set after the method is complete 1623 */ 1624os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1625 os::SuspendResume::State to) 1626{ 1627 os::SuspendResume::State result = 1628 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1629 if (result == from) { 1630 // success 1631 return to; 1632 } 1633 return result; 1634} 1635#endif 1636