os.cpp revision 5266:40136aa2cdb1
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 317void os::init_before_ergo() { 318 // We need to initialize large page support here because ergonomics takes some 319 // decisions depending on large page support and the calculated large page size. 320 large_page_init(); 321} 322 323void os::signal_init() { 324 if (!ReduceSignalUsage) { 325 // Setup JavaThread for processing signals 326 EXCEPTION_MARK; 327 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 328 instanceKlassHandle klass (THREAD, k); 329 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 330 331 const char thread_name[] = "Signal Dispatcher"; 332 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 333 334 // Initialize thread_oop to put it into the system threadGroup 335 Handle thread_group (THREAD, Universe::system_thread_group()); 336 JavaValue result(T_VOID); 337 JavaCalls::call_special(&result, thread_oop, 338 klass, 339 vmSymbols::object_initializer_name(), 340 vmSymbols::threadgroup_string_void_signature(), 341 thread_group, 342 string, 343 CHECK); 344 345 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 346 JavaCalls::call_special(&result, 347 thread_group, 348 group, 349 vmSymbols::add_method_name(), 350 vmSymbols::thread_void_signature(), 351 thread_oop, // ARG 1 352 CHECK); 353 354 os::signal_init_pd(); 355 356 { MutexLocker mu(Threads_lock); 357 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 358 359 // At this point it may be possible that no osthread was created for the 360 // JavaThread due to lack of memory. We would have to throw an exception 361 // in that case. However, since this must work and we do not allow 362 // exceptions anyway, check and abort if this fails. 363 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 364 vm_exit_during_initialization("java.lang.OutOfMemoryError", 365 "unable to create new native thread"); 366 } 367 368 java_lang_Thread::set_thread(thread_oop(), signal_thread); 369 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 370 java_lang_Thread::set_daemon(thread_oop()); 371 372 signal_thread->set_threadObj(thread_oop()); 373 Threads::add(signal_thread); 374 Thread::start(signal_thread); 375 } 376 // Handle ^BREAK 377 os::signal(SIGBREAK, os::user_handler()); 378 } 379} 380 381 382void os::terminate_signal_thread() { 383 if (!ReduceSignalUsage) 384 signal_notify(sigexitnum_pd()); 385} 386 387 388// --------------------- loading libraries --------------------- 389 390typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 391extern struct JavaVM_ main_vm; 392 393static void* _native_java_library = NULL; 394 395void* os::native_java_library() { 396 if (_native_java_library == NULL) { 397 char buffer[JVM_MAXPATHLEN]; 398 char ebuf[1024]; 399 400 // Try to load verify dll first. In 1.3 java dll depends on it and is not 401 // always able to find it when the loading executable is outside the JDK. 402 // In order to keep working with 1.2 we ignore any loading errors. 403 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 404 "verify")) { 405 dll_load(buffer, ebuf, sizeof(ebuf)); 406 } 407 408 // Load java dll 409 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 410 "java")) { 411 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 412 } 413 if (_native_java_library == NULL) { 414 vm_exit_during_initialization("Unable to load native library", ebuf); 415 } 416 417#if defined(__OpenBSD__) 418 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 419 // ignore errors 420 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 421 "net")) { 422 dll_load(buffer, ebuf, sizeof(ebuf)); 423 } 424#endif 425 } 426 static jboolean onLoaded = JNI_FALSE; 427 if (onLoaded) { 428 // We may have to wait to fire OnLoad until TLS is initialized. 429 if (ThreadLocalStorage::is_initialized()) { 430 // The JNI_OnLoad handling is normally done by method load in 431 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 432 // explicitly so we have to check for JNI_OnLoad as well 433 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 434 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 435 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 436 if (JNI_OnLoad != NULL) { 437 JavaThread* thread = JavaThread::current(); 438 ThreadToNativeFromVM ttn(thread); 439 HandleMark hm(thread); 440 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 441 onLoaded = JNI_TRUE; 442 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 443 vm_exit_during_initialization("Unsupported JNI version"); 444 } 445 } 446 } 447 } 448 return _native_java_library; 449} 450 451/* 452 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 453 * If check_lib == true then we are looking for an 454 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 455 * this library is statically linked into the image. 456 * If check_lib == false then we will look for the appropriate symbol in the 457 * executable if agent_lib->is_static_lib() == true or in the shared library 458 * referenced by 'handle'. 459 */ 460void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 461 const char *syms[], size_t syms_len) { 462 const char *lib_name; 463 void *handle = agent_lib->os_lib(); 464 void *entryName = NULL; 465 char *agent_function_name; 466 size_t i; 467 468 // If checking then use the agent name otherwise test is_static_lib() to 469 // see how to process this lookup 470 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 471 for (i = 0; i < syms_len; i++) { 472 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 473 if (agent_function_name == NULL) { 474 break; 475 } 476 entryName = dll_lookup(handle, agent_function_name); 477 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread); 478 if (entryName != NULL) { 479 break; 480 } 481 } 482 return entryName; 483} 484 485// See if the passed in agent is statically linked into the VM image. 486bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 487 size_t syms_len) { 488 void *ret; 489 void *proc_handle; 490 void *save_handle; 491 492 if (agent_lib->name() == NULL) { 493 return false; 494 } 495 proc_handle = get_default_process_handle(); 496 // Check for Agent_OnLoad/Attach_lib_name function 497 save_handle = agent_lib->os_lib(); 498 // We want to look in this process' symbol table. 499 agent_lib->set_os_lib(proc_handle); 500 ret = find_agent_function(agent_lib, true, syms, syms_len); 501 agent_lib->set_os_lib(save_handle); 502 if (ret != NULL) { 503 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 504 agent_lib->set_os_lib(proc_handle); 505 agent_lib->set_valid(); 506 agent_lib->set_static_lib(true); 507 return true; 508 } 509 return false; 510} 511 512// --------------------- heap allocation utilities --------------------- 513 514char *os::strdup(const char *str, MEMFLAGS flags) { 515 size_t size = strlen(str); 516 char *dup_str = (char *)malloc(size + 1, flags); 517 if (dup_str == NULL) return NULL; 518 strcpy(dup_str, str); 519 return dup_str; 520} 521 522 523 524#ifdef ASSERT 525#define space_before (MallocCushion + sizeof(double)) 526#define space_after MallocCushion 527#define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) 528#define size_addr_from_obj(p) ((size_t*)p - 1) 529// MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly 530// NB: cannot be debug variable, because these aren't set from the command line until 531// *after* the first few allocs already happened 532#define MallocCushion 16 533#else 534#define space_before 0 535#define space_after 0 536#define size_addr_from_base(p) should not use w/o ASSERT 537#define size_addr_from_obj(p) should not use w/o ASSERT 538#define MallocCushion 0 539#endif 540#define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 541 542#ifdef ASSERT 543inline size_t get_size(void* obj) { 544 size_t size = *size_addr_from_obj(obj); 545 if (size < 0) { 546 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten (" 547 SIZE_FORMAT ")", obj, size)); 548 } 549 return size; 550} 551 552u_char* find_cushion_backwards(u_char* start) { 553 u_char* p = start; 554 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || 555 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; 556 // ok, we have four consecutive marker bytes; find start 557 u_char* q = p - 4; 558 while (*q == badResourceValue) q--; 559 return q + 1; 560} 561 562u_char* find_cushion_forwards(u_char* start) { 563 u_char* p = start; 564 while (p[0] != badResourceValue || p[1] != badResourceValue || 565 p[2] != badResourceValue || p[3] != badResourceValue) p++; 566 // ok, we have four consecutive marker bytes; find end of cushion 567 u_char* q = p + 4; 568 while (*q == badResourceValue) q++; 569 return q - MallocCushion; 570} 571 572void print_neighbor_blocks(void* ptr) { 573 // find block allocated before ptr (not entirely crash-proof) 574 if (MallocCushion < 4) { 575 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); 576 return; 577 } 578 u_char* start_of_this_block = (u_char*)ptr - space_before; 579 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; 580 // look for cushion in front of prev. block 581 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); 582 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); 583 u_char* obj = start_of_prev_block + space_before; 584 if (size <= 0 ) { 585 // start is bad; mayhave been confused by OS data inbetween objects 586 // search one more backwards 587 start_of_prev_block = find_cushion_backwards(start_of_prev_block); 588 size = *size_addr_from_base(start_of_prev_block); 589 obj = start_of_prev_block + space_before; 590 } 591 592 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { 593 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 594 } else { 595 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 596 } 597 598 // now find successor block 599 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; 600 start_of_next_block = find_cushion_forwards(start_of_next_block); 601 u_char* next_obj = start_of_next_block + space_before; 602 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); 603 if (start_of_next_block[0] == badResourceValue && 604 start_of_next_block[1] == badResourceValue && 605 start_of_next_block[2] == badResourceValue && 606 start_of_next_block[3] == badResourceValue) { 607 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 608 } else { 609 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 610 } 611} 612 613 614void report_heap_error(void* memblock, void* bad, const char* where) { 615 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 616 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock); 617 print_neighbor_blocks(memblock); 618 fatal("memory stomping error"); 619} 620 621void verify_block(void* memblock) { 622 size_t size = get_size(memblock); 623 if (MallocCushion) { 624 u_char* ptr = (u_char*)memblock - space_before; 625 for (int i = 0; i < MallocCushion; i++) { 626 if (ptr[i] != badResourceValue) { 627 report_heap_error(memblock, ptr+i, "in front of"); 628 } 629 } 630 u_char* end = (u_char*)memblock + size + space_after; 631 for (int j = -MallocCushion; j < 0; j++) { 632 if (end[j] != badResourceValue) { 633 report_heap_error(memblock, end+j, "after"); 634 } 635 } 636 } 637} 638#endif 639 640// 641// This function supports testing of the malloc out of memory 642// condition without really running the system out of memory. 643// 644static u_char* testMalloc(size_t alloc_size) { 645 assert(MallocMaxTestWords > 0, "sanity check"); 646 647 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 648 return NULL; 649 } 650 651 u_char* ptr = (u_char*)::malloc(alloc_size); 652 653 if (ptr != NULL) { 654 Atomic::add(((jint) (alloc_size / BytesPerWord)), 655 (volatile jint *) &cur_malloc_words); 656 } 657 return ptr; 658} 659 660void* os::malloc(size_t size, MEMFLAGS memflags, address caller) { 661 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 662 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 663 664#ifdef ASSERT 665 // checking for the WatcherThread and crash_protection first 666 // since os::malloc can be called when the libjvm.{dll,so} is 667 // first loaded and we don't have a thread yet. 668 // try to find the thread after we see that the watcher thread 669 // exists and has crash protection. 670 WatcherThread *wt = WatcherThread::watcher_thread(); 671 if (wt != NULL && wt->has_crash_protection()) { 672 Thread* thread = ThreadLocalStorage::get_thread_slow(); 673 if (thread == wt) { 674 assert(!wt->has_crash_protection(), 675 "Can't malloc with crash protection from WatcherThread"); 676 } 677 } 678#endif 679 680 if (size == 0) { 681 // return a valid pointer if size is zero 682 // if NULL is returned the calling functions assume out of memory. 683 size = 1; 684 } 685 686 const size_t alloc_size = size + space_before + space_after; 687 688 if (size > alloc_size) { // Check for rollover. 689 return NULL; 690 } 691 692 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 693 694 u_char* ptr; 695 696 if (MallocMaxTestWords > 0) { 697 ptr = testMalloc(alloc_size); 698 } else { 699 ptr = (u_char*)::malloc(alloc_size); 700 } 701 702#ifdef ASSERT 703 if (ptr == NULL) return NULL; 704 if (MallocCushion) { 705 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; 706 u_char* end = ptr + space_before + size; 707 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; 708 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; 709 } 710 // put size just before data 711 *size_addr_from_base(ptr) = size; 712#endif 713 u_char* memblock = ptr + space_before; 714 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 715 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 716 breakpoint(); 717 } 718 debug_only(if (paranoid) verify_block(memblock)); 719 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 720 721 // we do not track MallocCushion memory 722 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller); 723 724 return memblock; 725} 726 727 728void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) { 729#ifndef ASSERT 730 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 731 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 732 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker(); 733 void* ptr = ::realloc(memblock, size); 734 if (ptr != NULL) { 735 tkr.record((address)memblock, (address)ptr, size, memflags, 736 caller == 0 ? CALLER_PC : caller); 737 } else { 738 tkr.discard(); 739 } 740 return ptr; 741#else 742 if (memblock == NULL) { 743 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller)); 744 } 745 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 746 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 747 breakpoint(); 748 } 749 verify_block(memblock); 750 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 751 if (size == 0) return NULL; 752 // always move the block 753 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller); 754 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 755 // Copy to new memory if malloc didn't fail 756 if ( ptr != NULL ) { 757 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); 758 if (paranoid) verify_block(ptr); 759 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 760 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 761 breakpoint(); 762 } 763 free(memblock); 764 } 765 return ptr; 766#endif 767} 768 769 770void os::free(void *memblock, MEMFLAGS memflags) { 771 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 772#ifdef ASSERT 773 if (memblock == NULL) return; 774 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 775 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 776 breakpoint(); 777 } 778 verify_block(memblock); 779 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 780 // Added by detlefs. 781 if (MallocCushion) { 782 u_char* ptr = (u_char*)memblock - space_before; 783 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { 784 guarantee(*p == badResourceValue, 785 "Thing freed should be malloc result."); 786 *p = (u_char)freeBlockPad; 787 } 788 size_t size = get_size(memblock); 789 inc_stat_counter(&free_bytes, size); 790 u_char* end = ptr + space_before + size; 791 for (u_char* q = end; q < end + MallocCushion; q++) { 792 guarantee(*q == badResourceValue, 793 "Thing freed should be malloc result."); 794 *q = (u_char)freeBlockPad; 795 } 796 if (PrintMalloc && tty != NULL) 797 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 798 } else if (PrintMalloc && tty != NULL) { 799 // tty->print_cr("os::free %p", memblock); 800 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock); 801 } 802#endif 803 MemTracker::record_free((address)memblock, memflags); 804 805 ::free((char*)memblock - space_before); 806} 807 808void os::init_random(long initval) { 809 _rand_seed = initval; 810} 811 812 813long os::random() { 814 /* standard, well-known linear congruential random generator with 815 * next_rand = (16807*seed) mod (2**31-1) 816 * see 817 * (1) "Random Number Generators: Good Ones Are Hard to Find", 818 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 819 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 820 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 821 */ 822 const long a = 16807; 823 const unsigned long m = 2147483647; 824 const long q = m / a; assert(q == 127773, "weird math"); 825 const long r = m % a; assert(r == 2836, "weird math"); 826 827 // compute az=2^31p+q 828 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 829 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 830 lo += (hi & 0x7FFF) << 16; 831 832 // if q overflowed, ignore the overflow and increment q 833 if (lo > m) { 834 lo &= m; 835 ++lo; 836 } 837 lo += hi >> 15; 838 839 // if (p+q) overflowed, ignore the overflow and increment (p+q) 840 if (lo > m) { 841 lo &= m; 842 ++lo; 843 } 844 return (_rand_seed = lo); 845} 846 847// The INITIALIZED state is distinguished from the SUSPENDED state because the 848// conditions in which a thread is first started are different from those in which 849// a suspension is resumed. These differences make it hard for us to apply the 850// tougher checks when starting threads that we want to do when resuming them. 851// However, when start_thread is called as a result of Thread.start, on a Java 852// thread, the operation is synchronized on the Java Thread object. So there 853// cannot be a race to start the thread and hence for the thread to exit while 854// we are working on it. Non-Java threads that start Java threads either have 855// to do so in a context in which races are impossible, or should do appropriate 856// locking. 857 858void os::start_thread(Thread* thread) { 859 // guard suspend/resume 860 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 861 OSThread* osthread = thread->osthread(); 862 osthread->set_state(RUNNABLE); 863 pd_start_thread(thread); 864} 865 866//--------------------------------------------------------------------------- 867// Helper functions for fatal error handler 868 869void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 870 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 871 872 int cols = 0; 873 int cols_per_line = 0; 874 switch (unitsize) { 875 case 1: cols_per_line = 16; break; 876 case 2: cols_per_line = 8; break; 877 case 4: cols_per_line = 4; break; 878 case 8: cols_per_line = 2; break; 879 default: return; 880 } 881 882 address p = start; 883 st->print(PTR_FORMAT ": ", start); 884 while (p < end) { 885 switch (unitsize) { 886 case 1: st->print("%02x", *(u1*)p); break; 887 case 2: st->print("%04x", *(u2*)p); break; 888 case 4: st->print("%08x", *(u4*)p); break; 889 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 890 } 891 p += unitsize; 892 cols++; 893 if (cols >= cols_per_line && p < end) { 894 cols = 0; 895 st->cr(); 896 st->print(PTR_FORMAT ": ", p); 897 } else { 898 st->print(" "); 899 } 900 } 901 st->cr(); 902} 903 904void os::print_environment_variables(outputStream* st, const char** env_list, 905 char* buffer, int len) { 906 if (env_list) { 907 st->print_cr("Environment Variables:"); 908 909 for (int i = 0; env_list[i] != NULL; i++) { 910 if (getenv(env_list[i], buffer, len)) { 911 st->print(env_list[i]); 912 st->print("="); 913 st->print_cr(buffer); 914 } 915 } 916 } 917} 918 919void os::print_cpu_info(outputStream* st) { 920 // cpu 921 st->print("CPU:"); 922 st->print("total %d", os::processor_count()); 923 // It's not safe to query number of active processors after crash 924 // st->print("(active %d)", os::active_processor_count()); 925 st->print(" %s", VM_Version::cpu_features()); 926 st->cr(); 927 pd_print_cpu_info(st); 928} 929 930void os::print_date_and_time(outputStream *st) { 931 time_t tloc; 932 (void)time(&tloc); 933 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 934 935 double t = os::elapsedTime(); 936 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 937 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 938 // before printf. We lost some precision, but who cares? 939 st->print_cr("elapsed time: %d seconds", (int)t); 940} 941 942// moved from debug.cpp (used to be find()) but still called from there 943// The verbose parameter is only set by the debug code in one case 944void os::print_location(outputStream* st, intptr_t x, bool verbose) { 945 address addr = (address)x; 946 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 947 if (b != NULL) { 948 if (b->is_buffer_blob()) { 949 // the interpreter is generated into a buffer blob 950 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 951 if (i != NULL) { 952 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 953 i->print_on(st); 954 return; 955 } 956 if (Interpreter::contains(addr)) { 957 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 958 " (not bytecode specific)", addr); 959 return; 960 } 961 // 962 if (AdapterHandlerLibrary::contains(b)) { 963 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 964 AdapterHandlerLibrary::print_handler_on(st, b); 965 } 966 // the stubroutines are generated into a buffer blob 967 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 968 if (d != NULL) { 969 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 970 d->print_on(st); 971 st->cr(); 972 return; 973 } 974 if (StubRoutines::contains(addr)) { 975 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 976 "stub routine", addr); 977 return; 978 } 979 // the InlineCacheBuffer is using stubs generated into a buffer blob 980 if (InlineCacheBuffer::contains(addr)) { 981 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 982 return; 983 } 984 VtableStub* v = VtableStubs::stub_containing(addr); 985 if (v != NULL) { 986 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 987 v->print_on(st); 988 st->cr(); 989 return; 990 } 991 } 992 nmethod* nm = b->as_nmethod_or_null(); 993 if (nm != NULL) { 994 ResourceMark rm; 995 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 996 addr, (int)(addr - nm->entry_point()), nm); 997 if (verbose) { 998 st->print(" for "); 999 nm->method()->print_value_on(st); 1000 } 1001 st->cr(); 1002 nm->print_nmethod(verbose); 1003 return; 1004 } 1005 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 1006 b->print_on(st); 1007 return; 1008 } 1009 1010 if (Universe::heap()->is_in(addr)) { 1011 HeapWord* p = Universe::heap()->block_start(addr); 1012 bool print = false; 1013 // If we couldn't find it it just may mean that heap wasn't parseable 1014 // See if we were just given an oop directly 1015 if (p != NULL && Universe::heap()->block_is_obj(p)) { 1016 print = true; 1017 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 1018 p = (HeapWord*) addr; 1019 print = true; 1020 } 1021 if (print) { 1022 if (p == (HeapWord*) addr) { 1023 st->print_cr(INTPTR_FORMAT " is an oop", addr); 1024 } else { 1025 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 1026 } 1027 oop(p)->print_on(st); 1028 return; 1029 } 1030 } else { 1031 if (Universe::heap()->is_in_reserved(addr)) { 1032 st->print_cr(INTPTR_FORMAT " is an unallocated location " 1033 "in the heap", addr); 1034 return; 1035 } 1036 } 1037 if (JNIHandles::is_global_handle((jobject) addr)) { 1038 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 1039 return; 1040 } 1041 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 1042 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 1043 return; 1044 } 1045#ifndef PRODUCT 1046 // we don't keep the block list in product mode 1047 if (JNIHandleBlock::any_contains((jobject) addr)) { 1048 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 1049 return; 1050 } 1051#endif 1052 1053 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1054 // Check for privilege stack 1055 if (thread->privileged_stack_top() != NULL && 1056 thread->privileged_stack_top()->contains(addr)) { 1057 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1058 "for thread: " INTPTR_FORMAT, addr, thread); 1059 if (verbose) thread->print_on(st); 1060 return; 1061 } 1062 // If the addr is a java thread print information about that. 1063 if (addr == (address)thread) { 1064 if (verbose) { 1065 thread->print_on(st); 1066 } else { 1067 st->print_cr(INTPTR_FORMAT " is a thread", addr); 1068 } 1069 return; 1070 } 1071 // If the addr is in the stack region for this thread then report that 1072 // and print thread info 1073 if (thread->stack_base() >= addr && 1074 addr > (thread->stack_base() - thread->stack_size())) { 1075 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1076 INTPTR_FORMAT, addr, thread); 1077 if (verbose) thread->print_on(st); 1078 return; 1079 } 1080 1081 } 1082 1083#ifndef PRODUCT 1084 // Check if in metaspace. 1085 if (ClassLoaderDataGraph::contains((address)addr)) { 1086 // Use addr->print() from the debugger instead (not here) 1087 st->print_cr(INTPTR_FORMAT 1088 " is pointing into metadata", addr); 1089 return; 1090 } 1091#endif 1092 1093 // Try an OS specific find 1094 if (os::find(addr, st)) { 1095 return; 1096 } 1097 1098 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1099} 1100 1101// Looks like all platforms except IA64 can use the same function to check 1102// if C stack is walkable beyond current frame. The check for fp() is not 1103// necessary on Sparc, but it's harmless. 1104bool os::is_first_C_frame(frame* fr) { 1105#if defined(IA64) && !defined(_WIN32) 1106 // On IA64 we have to check if the callers bsp is still valid 1107 // (i.e. within the register stack bounds). 1108 // Notice: this only works for threads created by the VM and only if 1109 // we walk the current stack!!! If we want to be able to walk 1110 // arbitrary other threads, we'll have to somehow store the thread 1111 // object in the frame. 1112 Thread *thread = Thread::current(); 1113 if ((address)fr->fp() <= 1114 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1115 // This check is a little hacky, because on Linux the first C 1116 // frame's ('start_thread') register stack frame starts at 1117 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1118 // ('__pthread_bound_body') register stack frame seems to really 1119 // start at "register_stack_base". 1120 return true; 1121 } else { 1122 return false; 1123 } 1124#elif defined(IA64) && defined(_WIN32) 1125 return true; 1126#else 1127 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1128 // Check usp first, because if that's bad the other accessors may fault 1129 // on some architectures. Ditto ufp second, etc. 1130 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1131 // sp on amd can be 32 bit aligned. 1132 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1133 1134 uintptr_t usp = (uintptr_t)fr->sp(); 1135 if ((usp & sp_align_mask) != 0) return true; 1136 1137 uintptr_t ufp = (uintptr_t)fr->fp(); 1138 if ((ufp & fp_align_mask) != 0) return true; 1139 1140 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1141 if ((old_sp & sp_align_mask) != 0) return true; 1142 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1143 1144 uintptr_t old_fp = (uintptr_t)fr->link(); 1145 if ((old_fp & fp_align_mask) != 0) return true; 1146 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1147 1148 // stack grows downwards; if old_fp is below current fp or if the stack 1149 // frame is too large, either the stack is corrupted or fp is not saved 1150 // on stack (i.e. on x86, ebp may be used as general register). The stack 1151 // is not walkable beyond current frame. 1152 if (old_fp < ufp) return true; 1153 if (old_fp - ufp > 64 * K) return true; 1154 1155 return false; 1156#endif 1157} 1158 1159#ifdef ASSERT 1160extern "C" void test_random() { 1161 const double m = 2147483647; 1162 double mean = 0.0, variance = 0.0, t; 1163 long reps = 10000; 1164 unsigned long seed = 1; 1165 1166 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1167 os::init_random(seed); 1168 long num; 1169 for (int k = 0; k < reps; k++) { 1170 num = os::random(); 1171 double u = (double)num / m; 1172 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1173 1174 // calculate mean and variance of the random sequence 1175 mean += u; 1176 variance += (u*u); 1177 } 1178 mean /= reps; 1179 variance /= (reps - 1); 1180 1181 assert(num == 1043618065, "bad seed"); 1182 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1183 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1184 const double eps = 0.0001; 1185 t = fabsd(mean - 0.5018); 1186 assert(t < eps, "bad mean"); 1187 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1188 assert(t < eps, "bad variance"); 1189} 1190#endif 1191 1192 1193// Set up the boot classpath. 1194 1195char* os::format_boot_path(const char* format_string, 1196 const char* home, 1197 int home_len, 1198 char fileSep, 1199 char pathSep) { 1200 assert((fileSep == '/' && pathSep == ':') || 1201 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1202 1203 // Scan the format string to determine the length of the actual 1204 // boot classpath, and handle platform dependencies as well. 1205 int formatted_path_len = 0; 1206 const char* p; 1207 for (p = format_string; *p != 0; ++p) { 1208 if (*p == '%') formatted_path_len += home_len - 1; 1209 ++formatted_path_len; 1210 } 1211 1212 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1213 if (formatted_path == NULL) { 1214 return NULL; 1215 } 1216 1217 // Create boot classpath from format, substituting separator chars and 1218 // java home directory. 1219 char* q = formatted_path; 1220 for (p = format_string; *p != 0; ++p) { 1221 switch (*p) { 1222 case '%': 1223 strcpy(q, home); 1224 q += home_len; 1225 break; 1226 case '/': 1227 *q++ = fileSep; 1228 break; 1229 case ':': 1230 *q++ = pathSep; 1231 break; 1232 default: 1233 *q++ = *p; 1234 } 1235 } 1236 *q = '\0'; 1237 1238 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1239 return formatted_path; 1240} 1241 1242 1243bool os::set_boot_path(char fileSep, char pathSep) { 1244 const char* home = Arguments::get_java_home(); 1245 int home_len = (int)strlen(home); 1246 1247 static const char* meta_index_dir_format = "%/lib/"; 1248 static const char* meta_index_format = "%/lib/meta-index"; 1249 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1250 if (meta_index == NULL) return false; 1251 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1252 if (meta_index_dir == NULL) return false; 1253 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1254 1255 // Any modification to the JAR-file list, for the boot classpath must be 1256 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1257 // path class JARs, are stripped for StackMapTable to reduce download size. 1258 static const char classpath_format[] = 1259 "%/lib/resources.jar:" 1260 "%/lib/rt.jar:" 1261 "%/lib/sunrsasign.jar:" 1262 "%/lib/jsse.jar:" 1263 "%/lib/jce.jar:" 1264 "%/lib/charsets.jar:" 1265 "%/lib/jfr.jar:" 1266#ifdef __APPLE__ 1267 "%/lib/JObjC.jar:" 1268#endif 1269 "%/classes"; 1270 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1271 if (sysclasspath == NULL) return false; 1272 Arguments::set_sysclasspath(sysclasspath); 1273 1274 return true; 1275} 1276 1277/* 1278 * Splits a path, based on its separator, the number of 1279 * elements is returned back in n. 1280 * It is the callers responsibility to: 1281 * a> check the value of n, and n may be 0. 1282 * b> ignore any empty path elements 1283 * c> free up the data. 1284 */ 1285char** os::split_path(const char* path, int* n) { 1286 *n = 0; 1287 if (path == NULL || strlen(path) == 0) { 1288 return NULL; 1289 } 1290 const char psepchar = *os::path_separator(); 1291 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1292 if (inpath == NULL) { 1293 return NULL; 1294 } 1295 strcpy(inpath, path); 1296 int count = 1; 1297 char* p = strchr(inpath, psepchar); 1298 // Get a count of elements to allocate memory 1299 while (p != NULL) { 1300 count++; 1301 p++; 1302 p = strchr(p, psepchar); 1303 } 1304 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1305 if (opath == NULL) { 1306 return NULL; 1307 } 1308 1309 // do the actual splitting 1310 p = inpath; 1311 for (int i = 0 ; i < count ; i++) { 1312 size_t len = strcspn(p, os::path_separator()); 1313 if (len > JVM_MAXPATHLEN) { 1314 return NULL; 1315 } 1316 // allocate the string and add terminator storage 1317 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1318 if (s == NULL) { 1319 return NULL; 1320 } 1321 strncpy(s, p, len); 1322 s[len] = '\0'; 1323 opath[i] = s; 1324 p += len + 1; 1325 } 1326 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1327 *n = count; 1328 return opath; 1329} 1330 1331void os::set_memory_serialize_page(address page) { 1332 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1333 _mem_serialize_page = (volatile int32_t *)page; 1334 // We initialize the serialization page shift count here 1335 // We assume a cache line size of 64 bytes 1336 assert(SerializePageShiftCount == count, 1337 "thread size changed, fix SerializePageShiftCount constant"); 1338 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1339} 1340 1341static volatile intptr_t SerializePageLock = 0; 1342 1343// This method is called from signal handler when SIGSEGV occurs while the current 1344// thread tries to store to the "read-only" memory serialize page during state 1345// transition. 1346void os::block_on_serialize_page_trap() { 1347 if (TraceSafepoint) { 1348 tty->print_cr("Block until the serialize page permission restored"); 1349 } 1350 // When VMThread is holding the SerializePageLock during modifying the 1351 // access permission of the memory serialize page, the following call 1352 // will block until the permission of that page is restored to rw. 1353 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1354 // this case, it's OK as the signal is synchronous and we know precisely when 1355 // it can occur. 1356 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1357 Thread::muxRelease(&SerializePageLock); 1358} 1359 1360// Serialize all thread state variables 1361void os::serialize_thread_states() { 1362 // On some platforms such as Solaris & Linux, the time duration of the page 1363 // permission restoration is observed to be much longer than expected due to 1364 // scheduler starvation problem etc. To avoid the long synchronization 1365 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1366 // the mutator thread if such case is encountered. See bug 6546278 for details. 1367 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1368 os::protect_memory((char *)os::get_memory_serialize_page(), 1369 os::vm_page_size(), MEM_PROT_READ); 1370 os::protect_memory((char *)os::get_memory_serialize_page(), 1371 os::vm_page_size(), MEM_PROT_RW); 1372 Thread::muxRelease(&SerializePageLock); 1373} 1374 1375// Returns true if the current stack pointer is above the stack shadow 1376// pages, false otherwise. 1377 1378bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1379 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1380 address sp = current_stack_pointer(); 1381 // Check if we have StackShadowPages above the yellow zone. This parameter 1382 // is dependent on the depth of the maximum VM call stack possible from 1383 // the handler for stack overflow. 'instanceof' in the stack overflow 1384 // handler or a println uses at least 8k stack of VM and native code 1385 // respectively. 1386 const int framesize_in_bytes = 1387 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1388 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1389 * vm_page_size()) + framesize_in_bytes; 1390 // The very lower end of the stack 1391 address stack_limit = thread->stack_base() - thread->stack_size(); 1392 return (sp > (stack_limit + reserved_area)); 1393} 1394 1395size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1396 uint min_pages) 1397{ 1398 assert(min_pages > 0, "sanity"); 1399 if (UseLargePages) { 1400 const size_t max_page_size = region_max_size / min_pages; 1401 1402 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1403 const size_t sz = _page_sizes[i]; 1404 const size_t mask = sz - 1; 1405 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1406 // The largest page size with no fragmentation. 1407 return sz; 1408 } 1409 1410 if (sz <= max_page_size) { 1411 // The largest page size that satisfies the min_pages requirement. 1412 return sz; 1413 } 1414 } 1415 } 1416 1417 return vm_page_size(); 1418} 1419 1420#ifndef PRODUCT 1421void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1422{ 1423 if (TracePageSizes) { 1424 tty->print("%s: ", str); 1425 for (int i = 0; i < count; ++i) { 1426 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1427 } 1428 tty->cr(); 1429 } 1430} 1431 1432void os::trace_page_sizes(const char* str, const size_t region_min_size, 1433 const size_t region_max_size, const size_t page_size, 1434 const char* base, const size_t size) 1435{ 1436 if (TracePageSizes) { 1437 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1438 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1439 " size=" SIZE_FORMAT, 1440 str, region_min_size, region_max_size, 1441 page_size, base, size); 1442 } 1443} 1444#endif // #ifndef PRODUCT 1445 1446// This is the working definition of a server class machine: 1447// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1448// because the graphics memory (?) sometimes masks physical memory. 1449// If you want to change the definition of a server class machine 1450// on some OS or platform, e.g., >=4GB on Windohs platforms, 1451// then you'll have to parameterize this method based on that state, 1452// as was done for logical processors here, or replicate and 1453// specialize this method for each platform. (Or fix os to have 1454// some inheritance structure and use subclassing. Sigh.) 1455// If you want some platform to always or never behave as a server 1456// class machine, change the setting of AlwaysActAsServerClassMachine 1457// and NeverActAsServerClassMachine in globals*.hpp. 1458bool os::is_server_class_machine() { 1459 // First check for the early returns 1460 if (NeverActAsServerClassMachine) { 1461 return false; 1462 } 1463 if (AlwaysActAsServerClassMachine) { 1464 return true; 1465 } 1466 // Then actually look at the machine 1467 bool result = false; 1468 const unsigned int server_processors = 2; 1469 const julong server_memory = 2UL * G; 1470 // We seem not to get our full complement of memory. 1471 // We allow some part (1/8?) of the memory to be "missing", 1472 // based on the sizes of DIMMs, and maybe graphics cards. 1473 const julong missing_memory = 256UL * M; 1474 1475 /* Is this a server class machine? */ 1476 if ((os::active_processor_count() >= (int)server_processors) && 1477 (os::physical_memory() >= (server_memory - missing_memory))) { 1478 const unsigned int logical_processors = 1479 VM_Version::logical_processors_per_package(); 1480 if (logical_processors > 1) { 1481 const unsigned int physical_packages = 1482 os::active_processor_count() / logical_processors; 1483 if (physical_packages > server_processors) { 1484 result = true; 1485 } 1486 } else { 1487 result = true; 1488 } 1489 } 1490 return result; 1491} 1492 1493void os::SuspendedThreadTask::run() { 1494 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1495 internal_do_task(); 1496 _done = true; 1497} 1498 1499bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1500 return os::pd_create_stack_guard_pages(addr, bytes); 1501} 1502 1503char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1504 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1505 if (result != NULL) { 1506 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1507 } 1508 1509 return result; 1510} 1511 1512char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1513 MEMFLAGS flags) { 1514 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1515 if (result != NULL) { 1516 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1517 MemTracker::record_virtual_memory_type((address)result, flags); 1518 } 1519 1520 return result; 1521} 1522 1523char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1524 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1525 if (result != NULL) { 1526 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1527 } 1528 return result; 1529} 1530 1531void os::split_reserved_memory(char *base, size_t size, 1532 size_t split, bool realloc) { 1533 pd_split_reserved_memory(base, size, split, realloc); 1534} 1535 1536bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1537 bool res = pd_commit_memory(addr, bytes, executable); 1538 if (res) { 1539 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1540 } 1541 return res; 1542} 1543 1544bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1545 bool executable) { 1546 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1547 if (res) { 1548 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1549 } 1550 return res; 1551} 1552 1553void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1554 const char* mesg) { 1555 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1556 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1557} 1558 1559void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1560 bool executable, const char* mesg) { 1561 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1562 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1563} 1564 1565bool os::uncommit_memory(char* addr, size_t bytes) { 1566 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1567 bool res = pd_uncommit_memory(addr, bytes); 1568 if (res) { 1569 tkr.record((address)addr, bytes); 1570 } else { 1571 tkr.discard(); 1572 } 1573 return res; 1574} 1575 1576bool os::release_memory(char* addr, size_t bytes) { 1577 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1578 bool res = pd_release_memory(addr, bytes); 1579 if (res) { 1580 tkr.record((address)addr, bytes); 1581 } else { 1582 tkr.discard(); 1583 } 1584 return res; 1585} 1586 1587 1588char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1589 char *addr, size_t bytes, bool read_only, 1590 bool allow_exec) { 1591 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1592 if (result != NULL) { 1593 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC); 1594 } 1595 return result; 1596} 1597 1598char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1599 char *addr, size_t bytes, bool read_only, 1600 bool allow_exec) { 1601 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1602 read_only, allow_exec); 1603} 1604 1605bool os::unmap_memory(char *addr, size_t bytes) { 1606 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1607 bool result = pd_unmap_memory(addr, bytes); 1608 if (result) { 1609 tkr.record((address)addr, bytes); 1610 } else { 1611 tkr.discard(); 1612 } 1613 return result; 1614} 1615 1616void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1617 pd_free_memory(addr, bytes, alignment_hint); 1618} 1619 1620void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1621 pd_realign_memory(addr, bytes, alignment_hint); 1622} 1623 1624#ifndef TARGET_OS_FAMILY_windows 1625/* try to switch state from state "from" to state "to" 1626 * returns the state set after the method is complete 1627 */ 1628os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1629 os::SuspendResume::State to) 1630{ 1631 os::SuspendResume::State result = 1632 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1633 if (result == from) { 1634 // success 1635 return to; 1636 } 1637 return result; 1638} 1639#endif 1640