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 68 OSThread* os::_starting_thread = NULL; 69 address os::_polling_page = NULL; 70 volatile int32_t* os::_mem_serialize_page = NULL; 71 uintptr_t os::_serialize_page_mask = 0; 72 long os::_rand_seed = 1; 73 int os::_processor_count = 0; 74 size_t os::_page_sizes[os::page_sizes_max]; 75 76 #ifndef PRODUCT 77 julong os::num_mallocs = 0; // # of calls to malloc/realloc 78 julong os::alloc_bytes = 0; // # of bytes allocated 79 julong os::num_frees = 0; // # of calls to free 80 julong os::free_bytes = 0; // # of bytes freed 81 #endif 82 83 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords 84 85 void 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. 99 char* 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 } 182 183 OSReturn 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() 206 OSReturn 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. 232 233 234 static 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 } 316 317 318 void 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 } 375 376 377 void os::terminate_signal_thread() { 378 if (!ReduceSignalUsage) 379 signal_notify(sigexitnum_pd()); 380 } 381 382 383 // --------------------- loading libraries --------------------- 384 385 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 386 extern struct JavaVM_ main_vm; 387 388 static void* _native_java_library = NULL; 389 390 void* 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 */ 455 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 456 const char *syms[], size_t syms_len) { 457 const char *lib_name; 458 void *handle = agent_lib->os_lib(); 459 void *entryName = NULL; 460 char *agent_function_name; 461 size_t i; 462 463 // If checking then use the agent name otherwise test is_static_lib() to 464 // see how to process this lookup 465 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 466 for (i = 0; i < syms_len; i++) { 467 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 468 if (agent_function_name == NULL) { 469 break; 470 } 471 entryName = dll_lookup(handle, agent_function_name); 472 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread); 473 if (entryName != NULL) { 474 break; 475 } 476 } 477 return entryName; 478 } 479 480 // See if the passed in agent is statically linked into the VM image. 481 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 482 size_t syms_len) { 483 void *ret; 484 void *proc_handle; 485 void *save_handle; 486 487 if (agent_lib->name() == NULL) { 488 return false; 489 } 490 proc_handle = get_default_process_handle(); 491 // Check for Agent_OnLoad/Attach_libname function 492 save_handle = agent_lib->os_lib(); 493 // We want to look in this process' symbol table. 494 agent_lib->set_os_lib(proc_handle); 495 ret = find_agent_function(agent_lib, true, syms, syms_len); 496 agent_lib->set_os_lib(save_handle); 497 if (ret != NULL) { 498 // Found an entry point like Agent_OnLoad_libname so we have a static agent 499 agent_lib->set_os_lib(proc_handle); 500 agent_lib->set_valid(); 501 agent_lib->set_static_lib(true); 502 return true; 503 } 504 return false; 505 } 506 507 // --------------------- heap allocation utilities --------------------- 508 509 char *os::strdup(const char *str, MEMFLAGS flags) { 510 size_t size = strlen(str); 511 char *dup_str = (char *)malloc(size + 1, flags); 512 if (dup_str == NULL) return NULL; 513 strcpy(dup_str, str); 514 return dup_str; 515 } 516 517 518 519 #ifdef ASSERT 520 #define space_before (MallocCushion + sizeof(double)) 521 #define space_after MallocCushion 522 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) 523 #define size_addr_from_obj(p) ((size_t*)p - 1) 524 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly 525 // NB: cannot be debug variable, because these aren't set from the command line until 526 // *after* the first few allocs already happened 527 #define MallocCushion 16 528 #else 529 #define space_before 0 530 #define space_after 0 531 #define size_addr_from_base(p) should not use w/o ASSERT 532 #define size_addr_from_obj(p) should not use w/o ASSERT 533 #define MallocCushion 0 534 #endif 535 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 536 537 #ifdef ASSERT 538 inline size_t get_size(void* obj) { 539 size_t size = *size_addr_from_obj(obj); 540 if (size < 0) { 541 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten (" 542 SIZE_FORMAT ")", obj, size)); 543 } 544 return size; 545 } 546 547 u_char* find_cushion_backwards(u_char* start) { 548 u_char* p = start; 549 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || 550 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; 551 // ok, we have four consecutive marker bytes; find start 552 u_char* q = p - 4; 553 while (*q == badResourceValue) q--; 554 return q + 1; 555 } 556 557 u_char* find_cushion_forwards(u_char* start) { 558 u_char* p = start; 559 while (p[0] != badResourceValue || p[1] != badResourceValue || 560 p[2] != badResourceValue || p[3] != badResourceValue) p++; 561 // ok, we have four consecutive marker bytes; find end of cushion 562 u_char* q = p + 4; 563 while (*q == badResourceValue) q++; 564 return q - MallocCushion; 565 } 566 567 void print_neighbor_blocks(void* ptr) { 568 // find block allocated before ptr (not entirely crash-proof) 569 if (MallocCushion < 4) { 570 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); 571 return; 572 } 573 u_char* start_of_this_block = (u_char*)ptr - space_before; 574 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; 575 // look for cushion in front of prev. block 576 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); 577 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); 578 u_char* obj = start_of_prev_block + space_before; 579 if (size <= 0 ) { 580 // start is bad; mayhave been confused by OS data inbetween objects 581 // search one more backwards 582 start_of_prev_block = find_cushion_backwards(start_of_prev_block); 583 size = *size_addr_from_base(start_of_prev_block); 584 obj = start_of_prev_block + space_before; 585 } 586 587 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { 588 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 589 } else { 590 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 591 } 592 593 // now find successor block 594 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; 595 start_of_next_block = find_cushion_forwards(start_of_next_block); 596 u_char* next_obj = start_of_next_block + space_before; 597 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); 598 if (start_of_next_block[0] == badResourceValue && 599 start_of_next_block[1] == badResourceValue && 600 start_of_next_block[2] == badResourceValue && 601 start_of_next_block[3] == badResourceValue) { 602 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 603 } else { 604 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 605 } 606 } 607 608 609 void report_heap_error(void* memblock, void* bad, const char* where) { 610 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 611 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock); 612 print_neighbor_blocks(memblock); 613 fatal("memory stomping error"); 614 } 615 616 void verify_block(void* memblock) { 617 size_t size = get_size(memblock); 618 if (MallocCushion) { 619 u_char* ptr = (u_char*)memblock - space_before; 620 for (int i = 0; i < MallocCushion; i++) { 621 if (ptr[i] != badResourceValue) { 622 report_heap_error(memblock, ptr+i, "in front of"); 623 } 624 } 625 u_char* end = (u_char*)memblock + size + space_after; 626 for (int j = -MallocCushion; j < 0; j++) { 627 if (end[j] != badResourceValue) { 628 report_heap_error(memblock, end+j, "after"); 629 } 630 } 631 } 632 } 633 #endif 634 635 // 636 // This function supports testing of the malloc out of memory 637 // condition without really running the system out of memory. 638 // 639 static u_char* testMalloc(size_t alloc_size) { 640 assert(MallocMaxTestWords > 0, "sanity check"); 641 642 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 643 return NULL; 644 } 645 646 u_char* ptr = (u_char*)::malloc(alloc_size); 647 648 if (ptr != NULL) { 649 Atomic::add(((jint) (alloc_size / BytesPerWord)), 650 (volatile jint *) &cur_malloc_words); 651 } 652 return ptr; 653 } 654 655 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) { 656 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 657 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 658 659 #ifdef ASSERT 660 // checking for the WatcherThread and crash_protection first 661 // since os::malloc can be called when the libjvm.{dll,so} is 662 // first loaded and we don't have a thread yet. 663 // try to find the thread after we see that the watcher thread 664 // exists and has crash protection. 665 WatcherThread *wt = WatcherThread::watcher_thread(); 666 if (wt != NULL && wt->has_crash_protection()) { 667 Thread* thread = ThreadLocalStorage::get_thread_slow(); 668 if (thread == wt) { 669 assert(!wt->has_crash_protection(), 670 "Can't malloc with crash protection from WatcherThread"); 671 } 672 } 673 #endif 674 675 if (size == 0) { 676 // return a valid pointer if size is zero 677 // if NULL is returned the calling functions assume out of memory. 678 size = 1; 679 } 680 681 const size_t alloc_size = size + space_before + space_after; 682 683 if (size > alloc_size) { // Check for rollover. 684 return NULL; 685 } 686 687 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 688 689 u_char* ptr; 690 691 if (MallocMaxTestWords > 0) { 692 ptr = testMalloc(alloc_size); 693 } else { 694 ptr = (u_char*)::malloc(alloc_size); 695 } 696 697 #ifdef ASSERT 698 if (ptr == NULL) return NULL; 699 if (MallocCushion) { 700 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; 701 u_char* end = ptr + space_before + size; 702 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; 703 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; 704 } 705 // put size just before data 706 *size_addr_from_base(ptr) = size; 707 #endif 708 u_char* memblock = ptr + space_before; 709 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 710 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 711 breakpoint(); 712 } 713 debug_only(if (paranoid) verify_block(memblock)); 714 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 715 716 // we do not track MallocCushion memory 717 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller); 718 719 return memblock; 720 } 721 722 723 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) { 724 #ifndef ASSERT 725 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 726 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 727 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker(); 728 void* ptr = ::realloc(memblock, size); 729 if (ptr != NULL) { 730 tkr.record((address)memblock, (address)ptr, size, memflags, 731 caller == 0 ? CALLER_PC : caller); 732 } else { 733 tkr.discard(); 734 } 735 return ptr; 736 #else 737 if (memblock == NULL) { 738 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller)); 739 } 740 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 741 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 742 breakpoint(); 743 } 744 verify_block(memblock); 745 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 746 if (size == 0) return NULL; 747 // always move the block 748 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller); 749 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 750 // Copy to new memory if malloc didn't fail 751 if ( ptr != NULL ) { 752 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); 753 if (paranoid) verify_block(ptr); 754 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 755 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 756 breakpoint(); 757 } 758 free(memblock); 759 } 760 return ptr; 761 #endif 762 } 763 764 765 void os::free(void *memblock, MEMFLAGS memflags) { 766 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 767 #ifdef ASSERT 768 if (memblock == NULL) return; 769 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 770 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 771 breakpoint(); 772 } 773 verify_block(memblock); 774 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 775 // Added by detlefs. 776 if (MallocCushion) { 777 u_char* ptr = (u_char*)memblock - space_before; 778 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { 779 guarantee(*p == badResourceValue, 780 "Thing freed should be malloc result."); 781 *p = (u_char)freeBlockPad; 782 } 783 size_t size = get_size(memblock); 784 inc_stat_counter(&free_bytes, size); 785 u_char* end = ptr + space_before + size; 786 for (u_char* q = end; q < end + MallocCushion; q++) { 787 guarantee(*q == badResourceValue, 788 "Thing freed should be malloc result."); 789 *q = (u_char)freeBlockPad; 790 } 791 if (PrintMalloc && tty != NULL) 792 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 793 } else if (PrintMalloc && tty != NULL) { 794 // tty->print_cr("os::free %p", memblock); 795 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock); 796 } 797 #endif 798 MemTracker::record_free((address)memblock, memflags); 799 800 ::free((char*)memblock - space_before); 801 } 802 803 void os::init_random(long initval) { 804 _rand_seed = initval; 805 } 806 807 808 long os::random() { 809 /* standard, well-known linear congruential random generator with 810 * next_rand = (16807*seed) mod (2**31-1) 811 * see 812 * (1) "Random Number Generators: Good Ones Are Hard to Find", 813 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 814 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 815 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 816 */ 817 const long a = 16807; 818 const unsigned long m = 2147483647; 819 const long q = m / a; assert(q == 127773, "weird math"); 820 const long r = m % a; assert(r == 2836, "weird math"); 821 822 // compute az=2^31p+q 823 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 824 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 825 lo += (hi & 0x7FFF) << 16; 826 827 // if q overflowed, ignore the overflow and increment q 828 if (lo > m) { 829 lo &= m; 830 ++lo; 831 } 832 lo += hi >> 15; 833 834 // if (p+q) overflowed, ignore the overflow and increment (p+q) 835 if (lo > m) { 836 lo &= m; 837 ++lo; 838 } 839 return (_rand_seed = lo); 840 } 841 842 // The INITIALIZED state is distinguished from the SUSPENDED state because the 843 // conditions in which a thread is first started are different from those in which 844 // a suspension is resumed. These differences make it hard for us to apply the 845 // tougher checks when starting threads that we want to do when resuming them. 846 // However, when start_thread is called as a result of Thread.start, on a Java 847 // thread, the operation is synchronized on the Java Thread object. So there 848 // cannot be a race to start the thread and hence for the thread to exit while 849 // we are working on it. Non-Java threads that start Java threads either have 850 // to do so in a context in which races are impossible, or should do appropriate 851 // locking. 852 853 void os::start_thread(Thread* thread) { 854 // guard suspend/resume 855 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 856 OSThread* osthread = thread->osthread(); 857 osthread->set_state(RUNNABLE); 858 pd_start_thread(thread); 859 } 860 861 //--------------------------------------------------------------------------- 862 // Helper functions for fatal error handler 863 864 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 865 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 866 867 int cols = 0; 868 int cols_per_line = 0; 869 switch (unitsize) { 870 case 1: cols_per_line = 16; break; 871 case 2: cols_per_line = 8; break; 872 case 4: cols_per_line = 4; break; 873 case 8: cols_per_line = 2; break; 874 default: return; 875 } 876 877 address p = start; 878 st->print(PTR_FORMAT ": ", start); 879 while (p < end) { 880 switch (unitsize) { 881 case 1: st->print("%02x", *(u1*)p); break; 882 case 2: st->print("%04x", *(u2*)p); break; 883 case 4: st->print("%08x", *(u4*)p); break; 884 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 885 } 886 p += unitsize; 887 cols++; 888 if (cols >= cols_per_line && p < end) { 889 cols = 0; 890 st->cr(); 891 st->print(PTR_FORMAT ": ", p); 892 } else { 893 st->print(" "); 894 } 895 } 896 st->cr(); 897 } 898 899 void os::print_environment_variables(outputStream* st, const char** env_list, 900 char* buffer, int len) { 901 if (env_list) { 902 st->print_cr("Environment Variables:"); 903 904 for (int i = 0; env_list[i] != NULL; i++) { 905 if (getenv(env_list[i], buffer, len)) { 906 st->print(env_list[i]); 907 st->print("="); 908 st->print_cr(buffer); 909 } 910 } 911 } 912 } 913 914 void os::print_cpu_info(outputStream* st) { 915 // cpu 916 st->print("CPU:"); 917 st->print("total %d", os::processor_count()); 918 // It's not safe to query number of active processors after crash 919 // st->print("(active %d)", os::active_processor_count()); 920 st->print(" %s", VM_Version::cpu_features()); 921 st->cr(); 922 pd_print_cpu_info(st); 923 } 924 925 void os::print_date_and_time(outputStream *st) { 926 time_t tloc; 927 (void)time(&tloc); 928 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 929 930 double t = os::elapsedTime(); 931 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 932 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 933 // before printf. We lost some precision, but who cares? 934 st->print_cr("elapsed time: %d seconds", (int)t); 935 } 936 937 // moved from debug.cpp (used to be find()) but still called from there 938 // The verbose parameter is only set by the debug code in one case 939 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 940 address addr = (address)x; 941 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 942 if (b != NULL) { 943 if (b->is_buffer_blob()) { 944 // the interpreter is generated into a buffer blob 945 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 946 if (i != NULL) { 947 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 948 i->print_on(st); 949 return; 950 } 951 if (Interpreter::contains(addr)) { 952 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 953 " (not bytecode specific)", addr); 954 return; 955 } 956 // 957 if (AdapterHandlerLibrary::contains(b)) { 958 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 959 AdapterHandlerLibrary::print_handler_on(st, b); 960 } 961 // the stubroutines are generated into a buffer blob 962 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 963 if (d != NULL) { 964 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 965 d->print_on(st); 966 st->cr(); 967 return; 968 } 969 if (StubRoutines::contains(addr)) { 970 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 971 "stub routine", addr); 972 return; 973 } 974 // the InlineCacheBuffer is using stubs generated into a buffer blob 975 if (InlineCacheBuffer::contains(addr)) { 976 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 977 return; 978 } 979 VtableStub* v = VtableStubs::stub_containing(addr); 980 if (v != NULL) { 981 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 982 v->print_on(st); 983 st->cr(); 984 return; 985 } 986 } 987 nmethod* nm = b->as_nmethod_or_null(); 988 if (nm != NULL) { 989 ResourceMark rm; 990 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 991 addr, (int)(addr - nm->entry_point()), nm); 992 if (verbose) { 993 st->print(" for "); 994 nm->method()->print_value_on(st); 995 } 996 st->cr(); 997 nm->print_nmethod(verbose); 998 return; 999 } 1000 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 1001 b->print_on(st); 1002 return; 1003 } 1004 1005 if (Universe::heap()->is_in(addr)) { 1006 HeapWord* p = Universe::heap()->block_start(addr); 1007 bool print = false; 1008 // If we couldn't find it it just may mean that heap wasn't parseable 1009 // See if we were just given an oop directly 1010 if (p != NULL && Universe::heap()->block_is_obj(p)) { 1011 print = true; 1012 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 1013 p = (HeapWord*) addr; 1014 print = true; 1015 } 1016 if (print) { 1017 if (p == (HeapWord*) addr) { 1018 st->print_cr(INTPTR_FORMAT " is an oop", addr); 1019 } else { 1020 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 1021 } 1022 oop(p)->print_on(st); 1023 return; 1024 } 1025 } else { 1026 if (Universe::heap()->is_in_reserved(addr)) { 1027 st->print_cr(INTPTR_FORMAT " is an unallocated location " 1028 "in the heap", addr); 1029 return; 1030 } 1031 } 1032 if (JNIHandles::is_global_handle((jobject) addr)) { 1033 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 1034 return; 1035 } 1036 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 1037 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 1038 return; 1039 } 1040 #ifndef PRODUCT 1041 // we don't keep the block list in product mode 1042 if (JNIHandleBlock::any_contains((jobject) addr)) { 1043 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 1044 return; 1045 } 1046 #endif 1047 1048 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 1049 // Check for privilege stack 1050 if (thread->privileged_stack_top() != NULL && 1051 thread->privileged_stack_top()->contains(addr)) { 1052 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 1053 "for thread: " INTPTR_FORMAT, addr, thread); 1054 if (verbose) thread->print_on(st); 1055 return; 1056 } 1057 // If the addr is a java thread print information about that. 1058 if (addr == (address)thread) { 1059 if (verbose) { 1060 thread->print_on(st); 1061 } else { 1062 st->print_cr(INTPTR_FORMAT " is a thread", addr); 1063 } 1064 return; 1065 } 1066 // If the addr is in the stack region for this thread then report that 1067 // and print thread info 1068 if (thread->stack_base() >= addr && 1069 addr > (thread->stack_base() - thread->stack_size())) { 1070 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1071 INTPTR_FORMAT, addr, thread); 1072 if (verbose) thread->print_on(st); 1073 return; 1074 } 1075 1076 } 1077 1078 #ifndef PRODUCT 1079 // Check if in metaspace. 1080 if (ClassLoaderDataGraph::contains((address)addr)) { 1081 // Use addr->print() from the debugger instead (not here) 1082 st->print_cr(INTPTR_FORMAT 1083 " is pointing into metadata", addr); 1084 return; 1085 } 1086 #endif 1087 1088 // Try an OS specific find 1089 if (os::find(addr, st)) { 1090 return; 1091 } 1092 1093 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1094 } 1095 1096 // Looks like all platforms except IA64 can use the same function to check 1097 // if C stack is walkable beyond current frame. The check for fp() is not 1098 // necessary on Sparc, but it's harmless. 1099 bool os::is_first_C_frame(frame* fr) { 1100 #if defined(IA64) && !defined(_WIN32) 1101 // On IA64 we have to check if the callers bsp is still valid 1102 // (i.e. within the register stack bounds). 1103 // Notice: this only works for threads created by the VM and only if 1104 // we walk the current stack!!! If we want to be able to walk 1105 // arbitrary other threads, we'll have to somehow store the thread 1106 // object in the frame. 1107 Thread *thread = Thread::current(); 1108 if ((address)fr->fp() <= 1109 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1110 // This check is a little hacky, because on Linux the first C 1111 // frame's ('start_thread') register stack frame starts at 1112 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1113 // ('__pthread_bound_body') register stack frame seems to really 1114 // start at "register_stack_base". 1115 return true; 1116 } else { 1117 return false; 1118 } 1119 #elif defined(IA64) && defined(_WIN32) 1120 return true; 1121 #else 1122 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1123 // Check usp first, because if that's bad the other accessors may fault 1124 // on some architectures. Ditto ufp second, etc. 1125 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1126 // sp on amd can be 32 bit aligned. 1127 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1128 1129 uintptr_t usp = (uintptr_t)fr->sp(); 1130 if ((usp & sp_align_mask) != 0) return true; 1131 1132 uintptr_t ufp = (uintptr_t)fr->fp(); 1133 if ((ufp & fp_align_mask) != 0) return true; 1134 1135 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1136 if ((old_sp & sp_align_mask) != 0) return true; 1137 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1138 1139 uintptr_t old_fp = (uintptr_t)fr->link(); 1140 if ((old_fp & fp_align_mask) != 0) return true; 1141 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1142 1143 // stack grows downwards; if old_fp is below current fp or if the stack 1144 // frame is too large, either the stack is corrupted or fp is not saved 1145 // on stack (i.e. on x86, ebp may be used as general register). The stack 1146 // is not walkable beyond current frame. 1147 if (old_fp < ufp) return true; 1148 if (old_fp - ufp > 64 * K) return true; 1149 1150 return false; 1151 #endif 1152 } 1153 1154 #ifdef ASSERT 1155 extern "C" void test_random() { 1156 const double m = 2147483647; 1157 double mean = 0.0, variance = 0.0, t; 1158 long reps = 10000; 1159 unsigned long seed = 1; 1160 1161 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1162 os::init_random(seed); 1163 long num; 1164 for (int k = 0; k < reps; k++) { 1165 num = os::random(); 1166 double u = (double)num / m; 1167 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1168 1169 // calculate mean and variance of the random sequence 1170 mean += u; 1171 variance += (u*u); 1172 } 1173 mean /= reps; 1174 variance /= (reps - 1); 1175 1176 assert(num == 1043618065, "bad seed"); 1177 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1178 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1179 const double eps = 0.0001; 1180 t = fabsd(mean - 0.5018); 1181 assert(t < eps, "bad mean"); 1182 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1183 assert(t < eps, "bad variance"); 1184 } 1185 #endif 1186 1187 1188 // Set up the boot classpath. 1189 1190 char* os::format_boot_path(const char* format_string, 1191 const char* home, 1192 int home_len, 1193 char fileSep, 1194 char pathSep) { 1195 assert((fileSep == '/' && pathSep == ':') || 1196 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1197 1198 // Scan the format string to determine the length of the actual 1199 // boot classpath, and handle platform dependencies as well. 1200 int formatted_path_len = 0; 1201 const char* p; 1202 for (p = format_string; *p != 0; ++p) { 1203 if (*p == '%') formatted_path_len += home_len - 1; 1204 ++formatted_path_len; 1205 } 1206 1207 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1208 if (formatted_path == NULL) { 1209 return NULL; 1210 } 1211 1212 // Create boot classpath from format, substituting separator chars and 1213 // java home directory. 1214 char* q = formatted_path; 1215 for (p = format_string; *p != 0; ++p) { 1216 switch (*p) { 1217 case '%': 1218 strcpy(q, home); 1219 q += home_len; 1220 break; 1221 case '/': 1222 *q++ = fileSep; 1223 break; 1224 case ':': 1225 *q++ = pathSep; 1226 break; 1227 default: 1228 *q++ = *p; 1229 } 1230 } 1231 *q = '\0'; 1232 1233 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1234 return formatted_path; 1235 } 1236 1237 1238 bool os::set_boot_path(char fileSep, char pathSep) { 1239 const char* home = Arguments::get_java_home(); 1240 int home_len = (int)strlen(home); 1241 1242 static const char* meta_index_dir_format = "%/lib/"; 1243 static const char* meta_index_format = "%/lib/meta-index"; 1244 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1245 if (meta_index == NULL) return false; 1246 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1247 if (meta_index_dir == NULL) return false; 1248 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1249 1250 // Any modification to the JAR-file list, for the boot classpath must be 1251 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1252 // path class JARs, are stripped for StackMapTable to reduce download size. 1253 static const char classpath_format[] = 1254 "%/lib/resources.jar:" 1255 "%/lib/rt.jar:" 1256 "%/lib/sunrsasign.jar:" 1257 "%/lib/jsse.jar:" 1258 "%/lib/jce.jar:" 1259 "%/lib/charsets.jar:" 1260 "%/lib/jfr.jar:" 1261 #ifdef __APPLE__ 1262 "%/lib/JObjC.jar:" 1263 #endif 1264 "%/classes"; 1265 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1266 if (sysclasspath == NULL) return false; 1267 Arguments::set_sysclasspath(sysclasspath); 1268 1269 return true; 1270 } 1271 1272 /* 1273 * Splits a path, based on its separator, the number of 1274 * elements is returned back in n. 1275 * It is the callers responsibility to: 1276 * a> check the value of n, and n may be 0. 1277 * b> ignore any empty path elements 1278 * c> free up the data. 1279 */ 1280 char** os::split_path(const char* path, int* n) { 1281 *n = 0; 1282 if (path == NULL || strlen(path) == 0) { 1283 return NULL; 1284 } 1285 const char psepchar = *os::path_separator(); 1286 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1287 if (inpath == NULL) { 1288 return NULL; 1289 } 1290 strcpy(inpath, path); 1291 int count = 1; 1292 char* p = strchr(inpath, psepchar); 1293 // Get a count of elements to allocate memory 1294 while (p != NULL) { 1295 count++; 1296 p++; 1297 p = strchr(p, psepchar); 1298 } 1299 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1300 if (opath == NULL) { 1301 return NULL; 1302 } 1303 1304 // do the actual splitting 1305 p = inpath; 1306 for (int i = 0 ; i < count ; i++) { 1307 size_t len = strcspn(p, os::path_separator()); 1308 if (len > JVM_MAXPATHLEN) { 1309 return NULL; 1310 } 1311 // allocate the string and add terminator storage 1312 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1313 if (s == NULL) { 1314 return NULL; 1315 } 1316 strncpy(s, p, len); 1317 s[len] = '\0'; 1318 opath[i] = s; 1319 p += len + 1; 1320 } 1321 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1322 *n = count; 1323 return opath; 1324 } 1325 1326 void os::set_memory_serialize_page(address page) { 1327 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1328 _mem_serialize_page = (volatile int32_t *)page; 1329 // We initialize the serialization page shift count here 1330 // We assume a cache line size of 64 bytes 1331 assert(SerializePageShiftCount == count, 1332 "thread size changed, fix SerializePageShiftCount constant"); 1333 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1334 } 1335 1336 static volatile intptr_t SerializePageLock = 0; 1337 1338 // This method is called from signal handler when SIGSEGV occurs while the current 1339 // thread tries to store to the "read-only" memory serialize page during state 1340 // transition. 1341 void os::block_on_serialize_page_trap() { 1342 if (TraceSafepoint) { 1343 tty->print_cr("Block until the serialize page permission restored"); 1344 } 1345 // When VMThread is holding the SerializePageLock during modifying the 1346 // access permission of the memory serialize page, the following call 1347 // will block until the permission of that page is restored to rw. 1348 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1349 // this case, it's OK as the signal is synchronous and we know precisely when 1350 // it can occur. 1351 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1352 Thread::muxRelease(&SerializePageLock); 1353 } 1354 1355 // Serialize all thread state variables 1356 void os::serialize_thread_states() { 1357 // On some platforms such as Solaris & Linux, the time duration of the page 1358 // permission restoration is observed to be much longer than expected due to 1359 // scheduler starvation problem etc. To avoid the long synchronization 1360 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1361 // the mutator thread if such case is encountered. See bug 6546278 for details. 1362 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1363 os::protect_memory((char *)os::get_memory_serialize_page(), 1364 os::vm_page_size(), MEM_PROT_READ); 1365 os::protect_memory((char *)os::get_memory_serialize_page(), 1366 os::vm_page_size(), MEM_PROT_RW); 1367 Thread::muxRelease(&SerializePageLock); 1368 } 1369 1370 // Returns true if the current stack pointer is above the stack shadow 1371 // pages, false otherwise. 1372 1373 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1374 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1375 address sp = current_stack_pointer(); 1376 // Check if we have StackShadowPages above the yellow zone. This parameter 1377 // is dependent on the depth of the maximum VM call stack possible from 1378 // the handler for stack overflow. 'instanceof' in the stack overflow 1379 // handler or a println uses at least 8k stack of VM and native code 1380 // respectively. 1381 const int framesize_in_bytes = 1382 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1383 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1384 * vm_page_size()) + framesize_in_bytes; 1385 // The very lower end of the stack 1386 address stack_limit = thread->stack_base() - thread->stack_size(); 1387 return (sp > (stack_limit + reserved_area)); 1388 } 1389 1390 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1391 uint min_pages) 1392 { 1393 assert(min_pages > 0, "sanity"); 1394 if (UseLargePages) { 1395 const size_t max_page_size = region_max_size / min_pages; 1396 1397 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1398 const size_t sz = _page_sizes[i]; 1399 const size_t mask = sz - 1; 1400 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1401 // The largest page size with no fragmentation. 1402 return sz; 1403 } 1404 1405 if (sz <= max_page_size) { 1406 // The largest page size that satisfies the min_pages requirement. 1407 return sz; 1408 } 1409 } 1410 } 1411 1412 return vm_page_size(); 1413 } 1414 1415 #ifndef PRODUCT 1416 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1417 { 1418 if (TracePageSizes) { 1419 tty->print("%s: ", str); 1420 for (int i = 0; i < count; ++i) { 1421 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1422 } 1423 tty->cr(); 1424 } 1425 } 1426 1427 void os::trace_page_sizes(const char* str, const size_t region_min_size, 1428 const size_t region_max_size, const size_t page_size, 1429 const char* base, const size_t size) 1430 { 1431 if (TracePageSizes) { 1432 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1433 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1434 " size=" SIZE_FORMAT, 1435 str, region_min_size, region_max_size, 1436 page_size, base, size); 1437 } 1438 } 1439 #endif // #ifndef PRODUCT 1440 1441 // This is the working definition of a server class machine: 1442 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1443 // because the graphics memory (?) sometimes masks physical memory. 1444 // If you want to change the definition of a server class machine 1445 // on some OS or platform, e.g., >=4GB on Windohs platforms, 1446 // then you'll have to parameterize this method based on that state, 1447 // as was done for logical processors here, or replicate and 1448 // specialize this method for each platform. (Or fix os to have 1449 // some inheritance structure and use subclassing. Sigh.) 1450 // If you want some platform to always or never behave as a server 1451 // class machine, change the setting of AlwaysActAsServerClassMachine 1452 // and NeverActAsServerClassMachine in globals*.hpp. 1453 bool os::is_server_class_machine() { 1454 // First check for the early returns 1455 if (NeverActAsServerClassMachine) { 1456 return false; 1457 } 1458 if (AlwaysActAsServerClassMachine) { 1459 return true; 1460 } 1461 // Then actually look at the machine 1462 bool result = false; 1463 const unsigned int server_processors = 2; 1464 const julong server_memory = 2UL * G; 1465 // We seem not to get our full complement of memory. 1466 // We allow some part (1/8?) of the memory to be "missing", 1467 // based on the sizes of DIMMs, and maybe graphics cards. 1468 const julong missing_memory = 256UL * M; 1469 1470 /* Is this a server class machine? */ 1471 if ((os::active_processor_count() >= (int)server_processors) && 1472 (os::physical_memory() >= (server_memory - missing_memory))) { 1473 const unsigned int logical_processors = 1474 VM_Version::logical_processors_per_package(); 1475 if (logical_processors > 1) { 1476 const unsigned int physical_packages = 1477 os::active_processor_count() / logical_processors; 1478 if (physical_packages > server_processors) { 1479 result = true; 1480 } 1481 } else { 1482 result = true; 1483 } 1484 } 1485 return result; 1486 } 1487 1488 // Read file line by line, if line is longer than bsize, 1489 // skip rest of line. 1490 int os::get_line_chars(int fd, char* buf, const size_t bsize){ 1491 size_t sz, i = 0; 1492 1493 // read until EOF, EOL or buf is full 1494 while ((sz = (int) read(fd, &buf[i], 1)) == 1 && i < (bsize-2) && buf[i] != '\n') { 1495 ++i; 1496 } 1497 1498 if (buf[i] == '\n') { 1499 // EOL reached so ignore EOL character and return 1500 1501 buf[i] = 0; 1502 return (int) i; 1503 } 1504 1505 buf[i+1] = 0; 1506 1507 if (sz != 1) { 1508 // EOF reached. if we read chars before EOF return them and 1509 // return EOF on next call otherwise return EOF 1510 1511 return (i == 0) ? -1 : (int) i; 1512 } 1513 1514 // line is longer than size of buf, skip to EOL 1515 char ch; 1516 while (read(fd, &ch, 1) == 1 && ch != '\n') { 1517 // Do nothing 1518 } 1519 1520 // return initial part of line that fits in buf. 1521 // If we reached EOF, it will be returned on next call. 1522 1523 return (int) i; 1524 } 1525 1526 void os::SuspendedThreadTask::run() { 1527 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1528 internal_do_task(); 1529 _done = true; 1530 } 1531 1532 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1533 return os::pd_create_stack_guard_pages(addr, bytes); 1534 } 1535 1536 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1537 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1538 if (result != NULL) { 1539 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1540 } 1541 1542 return result; 1543 } 1544 1545 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1546 MEMFLAGS flags) { 1547 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1548 if (result != NULL) { 1549 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1550 MemTracker::record_virtual_memory_type((address)result, flags); 1551 } 1552 1553 return result; 1554 } 1555 1556 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1557 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1558 if (result != NULL) { 1559 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC); 1560 } 1561 return result; 1562 } 1563 1564 void os::split_reserved_memory(char *base, size_t size, 1565 size_t split, bool realloc) { 1566 pd_split_reserved_memory(base, size, split, realloc); 1567 } 1568 1569 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1570 bool res = pd_commit_memory(addr, bytes, executable); 1571 if (res) { 1572 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1573 } 1574 return res; 1575 } 1576 1577 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1578 bool executable) { 1579 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1580 if (res) { 1581 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1582 } 1583 return res; 1584 } 1585 1586 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1587 const char* mesg) { 1588 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1589 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1590 } 1591 1592 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1593 bool executable, const char* mesg) { 1594 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1595 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1596 } 1597 1598 bool os::uncommit_memory(char* addr, size_t bytes) { 1599 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1600 bool res = pd_uncommit_memory(addr, bytes); 1601 if (res) { 1602 tkr.record((address)addr, bytes); 1603 } else { 1604 tkr.discard(); 1605 } 1606 return res; 1607 } 1608 1609 bool os::release_memory(char* addr, size_t bytes) { 1610 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1611 bool res = pd_release_memory(addr, bytes); 1612 if (res) { 1613 tkr.record((address)addr, bytes); 1614 } else { 1615 tkr.discard(); 1616 } 1617 return res; 1618 } 1619 1620 1621 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1622 char *addr, size_t bytes, bool read_only, 1623 bool allow_exec) { 1624 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1625 if (result != NULL) { 1626 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC); 1627 } 1628 return result; 1629 } 1630 1631 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1632 char *addr, size_t bytes, bool read_only, 1633 bool allow_exec) { 1634 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1635 read_only, allow_exec); 1636 } 1637 1638 bool os::unmap_memory(char *addr, size_t bytes) { 1639 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1640 bool result = pd_unmap_memory(addr, bytes); 1641 if (result) { 1642 tkr.record((address)addr, bytes); 1643 } else { 1644 tkr.discard(); 1645 } 1646 return result; 1647 } 1648 1649 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1650 pd_free_memory(addr, bytes, alignment_hint); 1651 } 1652 1653 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1654 pd_realign_memory(addr, bytes, alignment_hint); 1655 } 1656 1657 #ifndef TARGET_OS_FAMILY_windows 1658 /* try to switch state from state "from" to state "to" 1659 * returns the state set after the method is complete 1660 */ 1661 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1662 os::SuspendResume::State to) 1663 { 1664 os::SuspendResume::State result = 1665 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1666 if (result == from) { 1667 // success 1668 return to; 1669 } 1670 return result; 1671 } 1672 #endif