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 true /* need_prologue */); 270 VMThread::execute(&op1); 271 } 272 if (JvmtiExport::should_post_data_dump()) { 273 JvmtiExport::post_data_dump(); 274 } 275 break; 276 } 277 default: { 278 // Dispatch the signal to java 279 HandleMark hm(THREAD); 280 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 281 KlassHandle klass (THREAD, k); 282 if (klass.not_null()) { 283 JavaValue result(T_VOID); 284 JavaCallArguments args; 285 args.push_int(sig); 286 JavaCalls::call_static( 287 &result, 288 klass, 289 vmSymbols::dispatch_name(), 290 vmSymbols::int_void_signature(), 291 &args, 292 THREAD 293 ); 294 } 295 if (HAS_PENDING_EXCEPTION) { 296 // tty is initialized early so we don't expect it to be null, but 297 // if it is we can't risk doing an initialization that might 298 // trigger additional out-of-memory conditions 299 if (tty != NULL) { 300 char klass_name[256]; 301 char tmp_sig_name[16]; 302 const char* sig_name = "UNKNOWN"; 303 InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 304 name()->as_klass_external_name(klass_name, 256); 305 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 306 sig_name = tmp_sig_name; 307 warning("Exception %s occurred dispatching signal %s to handler" 308 "- the VM may need to be forcibly terminated", 309 klass_name, sig_name ); 310 } 311 CLEAR_PENDING_EXCEPTION; 312 } 313 } 314 } 315 } 316 } 317 318 319 void os::signal_init() { 320 if (!ReduceSignalUsage) { 321 // Setup JavaThread for processing signals 322 EXCEPTION_MARK; 323 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 324 instanceKlassHandle klass (THREAD, k); 325 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 326 327 const char thread_name[] = "Signal Dispatcher"; 328 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 329 330 // Initialize thread_oop to put it into the system threadGroup 331 Handle thread_group (THREAD, Universe::system_thread_group()); 332 JavaValue result(T_VOID); 333 JavaCalls::call_special(&result, thread_oop, 334 klass, 335 vmSymbols::object_initializer_name(), 336 vmSymbols::threadgroup_string_void_signature(), 337 thread_group, 338 string, 339 CHECK); 340 341 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 342 JavaCalls::call_special(&result, 343 thread_group, 344 group, 345 vmSymbols::add_method_name(), 346 vmSymbols::thread_void_signature(), 347 thread_oop, // ARG 1 348 CHECK); 349 350 os::signal_init_pd(); 351 352 { MutexLocker mu(Threads_lock); 353 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 354 355 // At this point it may be possible that no osthread was created for the 356 // JavaThread due to lack of memory. We would have to throw an exception 357 // in that case. However, since this must work and we do not allow 358 // exceptions anyway, check and abort if this fails. 359 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 360 vm_exit_during_initialization("java.lang.OutOfMemoryError", 361 "unable to create new native thread"); 362 } 363 364 java_lang_Thread::set_thread(thread_oop(), signal_thread); 365 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 366 java_lang_Thread::set_daemon(thread_oop()); 367 368 signal_thread->set_threadObj(thread_oop()); 369 Threads::add(signal_thread); 370 Thread::start(signal_thread); 371 } 372 // Handle ^BREAK 373 os::signal(SIGBREAK, os::user_handler()); 374 } 375 } 376 377 378 void os::terminate_signal_thread() { 379 if (!ReduceSignalUsage) 380 signal_notify(sigexitnum_pd()); 381 } 382 383 384 // --------------------- loading libraries --------------------- 385 386 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 387 extern struct JavaVM_ main_vm; 388 389 static void* _native_java_library = NULL; 390 391 void* os::native_java_library() { 392 if (_native_java_library == NULL) { 393 char buffer[JVM_MAXPATHLEN]; 394 char ebuf[1024]; 395 396 // Try to load verify dll first. In 1.3 java dll depends on it and is not 397 // always able to find it when the loading executable is outside the JDK. 398 // In order to keep working with 1.2 we ignore any loading errors. 399 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 400 "verify")) { 401 dll_load(buffer, ebuf, sizeof(ebuf)); 402 } 403 404 // Load java dll 405 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 406 "java")) { 407 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 408 } 409 if (_native_java_library == NULL) { 410 vm_exit_during_initialization("Unable to load native library", ebuf); 411 } 412 413 #if defined(__OpenBSD__) 414 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 415 // ignore errors 416 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 417 "net")) { 418 dll_load(buffer, ebuf, sizeof(ebuf)); 419 } 420 #endif 421 } 422 static jboolean onLoaded = JNI_FALSE; 423 if (onLoaded) { 424 // We may have to wait to fire OnLoad until TLS is initialized. 425 if (ThreadLocalStorage::is_initialized()) { 426 // The JNI_OnLoad handling is normally done by method load in 427 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 428 // explicitly so we have to check for JNI_OnLoad as well 429 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 430 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 431 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 432 if (JNI_OnLoad != NULL) { 433 JavaThread* thread = JavaThread::current(); 434 ThreadToNativeFromVM ttn(thread); 435 HandleMark hm(thread); 436 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 437 onLoaded = JNI_TRUE; 438 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 439 vm_exit_during_initialization("Unsupported JNI version"); 440 } 441 } 442 } 443 } 444 return _native_java_library; 445 } 446 447 // --------------------- heap allocation utilities --------------------- 448 449 char *os::strdup(const char *str, MEMFLAGS flags) { 450 size_t size = strlen(str); 451 char *dup_str = (char *)malloc(size + 1, flags); 452 if (dup_str == NULL) return NULL; 453 strcpy(dup_str, str); 454 return dup_str; 455 } 456 457 458 459 #ifdef ASSERT 460 #define space_before (MallocCushion + sizeof(double)) 461 #define space_after MallocCushion 462 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) 463 #define size_addr_from_obj(p) ((size_t*)p - 1) 464 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly 465 // NB: cannot be debug variable, because these aren't set from the command line until 466 // *after* the first few allocs already happened 467 #define MallocCushion 16 468 #else 469 #define space_before 0 470 #define space_after 0 471 #define size_addr_from_base(p) should not use w/o ASSERT 472 #define size_addr_from_obj(p) should not use w/o ASSERT 473 #define MallocCushion 0 474 #endif 475 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 476 477 #ifdef ASSERT 478 inline size_t get_size(void* obj) { 479 size_t size = *size_addr_from_obj(obj); 480 if (size < 0) { 481 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten (" 482 SIZE_FORMAT ")", obj, size)); 483 } 484 return size; 485 } 486 487 u_char* find_cushion_backwards(u_char* start) { 488 u_char* p = start; 489 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || 490 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; 491 // ok, we have four consecutive marker bytes; find start 492 u_char* q = p - 4; 493 while (*q == badResourceValue) q--; 494 return q + 1; 495 } 496 497 u_char* find_cushion_forwards(u_char* start) { 498 u_char* p = start; 499 while (p[0] != badResourceValue || p[1] != badResourceValue || 500 p[2] != badResourceValue || p[3] != badResourceValue) p++; 501 // ok, we have four consecutive marker bytes; find end of cushion 502 u_char* q = p + 4; 503 while (*q == badResourceValue) q++; 504 return q - MallocCushion; 505 } 506 507 void print_neighbor_blocks(void* ptr) { 508 // find block allocated before ptr (not entirely crash-proof) 509 if (MallocCushion < 4) { 510 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); 511 return; 512 } 513 u_char* start_of_this_block = (u_char*)ptr - space_before; 514 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; 515 // look for cushion in front of prev. block 516 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); 517 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); 518 u_char* obj = start_of_prev_block + space_before; 519 if (size <= 0 ) { 520 // start is bad; mayhave been confused by OS data inbetween objects 521 // search one more backwards 522 start_of_prev_block = find_cushion_backwards(start_of_prev_block); 523 size = *size_addr_from_base(start_of_prev_block); 524 obj = start_of_prev_block + space_before; 525 } 526 527 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { 528 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 529 } else { 530 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 531 } 532 533 // now find successor block 534 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; 535 start_of_next_block = find_cushion_forwards(start_of_next_block); 536 u_char* next_obj = start_of_next_block + space_before; 537 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); 538 if (start_of_next_block[0] == badResourceValue && 539 start_of_next_block[1] == badResourceValue && 540 start_of_next_block[2] == badResourceValue && 541 start_of_next_block[3] == badResourceValue) { 542 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 543 } else { 544 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 545 } 546 } 547 548 549 void report_heap_error(void* memblock, void* bad, const char* where) { 550 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 551 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock); 552 print_neighbor_blocks(memblock); 553 fatal("memory stomping error"); 554 } 555 556 void verify_block(void* memblock) { 557 size_t size = get_size(memblock); 558 if (MallocCushion) { 559 u_char* ptr = (u_char*)memblock - space_before; 560 for (int i = 0; i < MallocCushion; i++) { 561 if (ptr[i] != badResourceValue) { 562 report_heap_error(memblock, ptr+i, "in front of"); 563 } 564 } 565 u_char* end = (u_char*)memblock + size + space_after; 566 for (int j = -MallocCushion; j < 0; j++) { 567 if (end[j] != badResourceValue) { 568 report_heap_error(memblock, end+j, "after"); 569 } 570 } 571 } 572 } 573 #endif 574 575 // 576 // This function supports testing of the malloc out of memory 577 // condition without really running the system out of memory. 578 // 579 static u_char* testMalloc(size_t alloc_size) { 580 assert(MallocMaxTestWords > 0, "sanity check"); 581 582 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 583 return NULL; 584 } 585 586 u_char* ptr = (u_char*)::malloc(alloc_size); 587 588 if (ptr != NULL) { 589 Atomic::add(((jint) (alloc_size / BytesPerWord)), 590 (volatile jint *) &cur_malloc_words); 591 } 592 return ptr; 593 } 594 595 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) { 596 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 597 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 598 599 if (size == 0) { 600 // return a valid pointer if size is zero 601 // if NULL is returned the calling functions assume out of memory. 602 size = 1; 603 } 604 605 const size_t alloc_size = size + space_before + space_after; 606 607 if (size > alloc_size) { // Check for rollover. 608 return NULL; 609 } 610 611 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 612 613 u_char* ptr; 614 615 if (MallocMaxTestWords > 0) { 616 ptr = testMalloc(alloc_size); 617 } else { 618 ptr = (u_char*)::malloc(alloc_size); 619 } 620 621 #ifdef ASSERT 622 if (ptr == NULL) return NULL; 623 if (MallocCushion) { 624 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; 625 u_char* end = ptr + space_before + size; 626 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; 627 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; 628 } 629 // put size just before data 630 *size_addr_from_base(ptr) = size; 631 #endif 632 u_char* memblock = ptr + space_before; 633 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 634 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 635 breakpoint(); 636 } 637 debug_only(if (paranoid) verify_block(memblock)); 638 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 639 640 // we do not track MallocCushion memory 641 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller); 642 643 return memblock; 644 } 645 646 647 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) { 648 #ifndef ASSERT 649 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 650 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 651 void* ptr = ::realloc(memblock, size); 652 if (ptr != NULL) { 653 MemTracker::record_realloc((address)memblock, (address)ptr, size, memflags, 654 caller == 0 ? CALLER_PC : caller); 655 } 656 return ptr; 657 #else 658 if (memblock == NULL) { 659 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller)); 660 } 661 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 662 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 663 breakpoint(); 664 } 665 verify_block(memblock); 666 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 667 if (size == 0) return NULL; 668 // always move the block 669 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller); 670 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 671 // Copy to new memory if malloc didn't fail 672 if ( ptr != NULL ) { 673 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); 674 if (paranoid) verify_block(ptr); 675 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 676 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 677 breakpoint(); 678 } 679 free(memblock); 680 } 681 return ptr; 682 #endif 683 } 684 685 686 void os::free(void *memblock, MEMFLAGS memflags) { 687 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 688 #ifdef ASSERT 689 if (memblock == NULL) return; 690 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 691 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 692 breakpoint(); 693 } 694 verify_block(memblock); 695 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 696 // Added by detlefs. 697 if (MallocCushion) { 698 u_char* ptr = (u_char*)memblock - space_before; 699 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { 700 guarantee(*p == badResourceValue, 701 "Thing freed should be malloc result."); 702 *p = (u_char)freeBlockPad; 703 } 704 size_t size = get_size(memblock); 705 inc_stat_counter(&free_bytes, size); 706 u_char* end = ptr + space_before + size; 707 for (u_char* q = end; q < end + MallocCushion; q++) { 708 guarantee(*q == badResourceValue, 709 "Thing freed should be malloc result."); 710 *q = (u_char)freeBlockPad; 711 } 712 if (PrintMalloc && tty != NULL) 713 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 714 } else if (PrintMalloc && tty != NULL) { 715 // tty->print_cr("os::free %p", memblock); 716 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock); 717 } 718 #endif 719 MemTracker::record_free((address)memblock, memflags); 720 721 ::free((char*)memblock - space_before); 722 } 723 724 void os::init_random(long initval) { 725 _rand_seed = initval; 726 } 727 728 729 long os::random() { 730 /* standard, well-known linear congruential random generator with 731 * next_rand = (16807*seed) mod (2**31-1) 732 * see 733 * (1) "Random Number Generators: Good Ones Are Hard to Find", 734 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 735 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 736 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 737 */ 738 const long a = 16807; 739 const unsigned long m = 2147483647; 740 const long q = m / a; assert(q == 127773, "weird math"); 741 const long r = m % a; assert(r == 2836, "weird math"); 742 743 // compute az=2^31p+q 744 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 745 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 746 lo += (hi & 0x7FFF) << 16; 747 748 // if q overflowed, ignore the overflow and increment q 749 if (lo > m) { 750 lo &= m; 751 ++lo; 752 } 753 lo += hi >> 15; 754 755 // if (p+q) overflowed, ignore the overflow and increment (p+q) 756 if (lo > m) { 757 lo &= m; 758 ++lo; 759 } 760 return (_rand_seed = lo); 761 } 762 763 // The INITIALIZED state is distinguished from the SUSPENDED state because the 764 // conditions in which a thread is first started are different from those in which 765 // a suspension is resumed. These differences make it hard for us to apply the 766 // tougher checks when starting threads that we want to do when resuming them. 767 // However, when start_thread is called as a result of Thread.start, on a Java 768 // thread, the operation is synchronized on the Java Thread object. So there 769 // cannot be a race to start the thread and hence for the thread to exit while 770 // we are working on it. Non-Java threads that start Java threads either have 771 // to do so in a context in which races are impossible, or should do appropriate 772 // locking. 773 774 void os::start_thread(Thread* thread) { 775 // guard suspend/resume 776 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 777 OSThread* osthread = thread->osthread(); 778 osthread->set_state(RUNNABLE); 779 pd_start_thread(thread); 780 } 781 782 //--------------------------------------------------------------------------- 783 // Helper functions for fatal error handler 784 785 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 786 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 787 788 int cols = 0; 789 int cols_per_line = 0; 790 switch (unitsize) { 791 case 1: cols_per_line = 16; break; 792 case 2: cols_per_line = 8; break; 793 case 4: cols_per_line = 4; break; 794 case 8: cols_per_line = 2; break; 795 default: return; 796 } 797 798 address p = start; 799 st->print(PTR_FORMAT ": ", start); 800 while (p < end) { 801 switch (unitsize) { 802 case 1: st->print("%02x", *(u1*)p); break; 803 case 2: st->print("%04x", *(u2*)p); break; 804 case 4: st->print("%08x", *(u4*)p); break; 805 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 806 } 807 p += unitsize; 808 cols++; 809 if (cols >= cols_per_line && p < end) { 810 cols = 0; 811 st->cr(); 812 st->print(PTR_FORMAT ": ", p); 813 } else { 814 st->print(" "); 815 } 816 } 817 st->cr(); 818 } 819 820 void os::print_environment_variables(outputStream* st, const char** env_list, 821 char* buffer, int len) { 822 if (env_list) { 823 st->print_cr("Environment Variables:"); 824 825 for (int i = 0; env_list[i] != NULL; i++) { 826 if (getenv(env_list[i], buffer, len)) { 827 st->print(env_list[i]); 828 st->print("="); 829 st->print_cr(buffer); 830 } 831 } 832 } 833 } 834 835 void os::print_cpu_info(outputStream* st) { 836 // cpu 837 st->print("CPU:"); 838 st->print("total %d", os::processor_count()); 839 // It's not safe to query number of active processors after crash 840 // st->print("(active %d)", os::active_processor_count()); 841 st->print(" %s", VM_Version::cpu_features()); 842 st->cr(); 843 pd_print_cpu_info(st); 844 } 845 846 void os::print_date_and_time(outputStream *st) { 847 time_t tloc; 848 (void)time(&tloc); 849 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 850 851 double t = os::elapsedTime(); 852 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 853 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 854 // before printf. We lost some precision, but who cares? 855 st->print_cr("elapsed time: %d seconds", (int)t); 856 } 857 858 // moved from debug.cpp (used to be find()) but still called from there 859 // The verbose parameter is only set by the debug code in one case 860 void os::print_location(outputStream* st, intptr_t x, bool verbose) { 861 address addr = (address)x; 862 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 863 if (b != NULL) { 864 if (b->is_buffer_blob()) { 865 // the interpreter is generated into a buffer blob 866 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 867 if (i != NULL) { 868 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 869 i->print_on(st); 870 return; 871 } 872 if (Interpreter::contains(addr)) { 873 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 874 " (not bytecode specific)", addr); 875 return; 876 } 877 // 878 if (AdapterHandlerLibrary::contains(b)) { 879 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 880 AdapterHandlerLibrary::print_handler_on(st, b); 881 } 882 // the stubroutines are generated into a buffer blob 883 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 884 if (d != NULL) { 885 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 886 d->print_on(st); 887 st->cr(); 888 return; 889 } 890 if (StubRoutines::contains(addr)) { 891 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 892 "stub routine", addr); 893 return; 894 } 895 // the InlineCacheBuffer is using stubs generated into a buffer blob 896 if (InlineCacheBuffer::contains(addr)) { 897 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 898 return; 899 } 900 VtableStub* v = VtableStubs::stub_containing(addr); 901 if (v != NULL) { 902 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 903 v->print_on(st); 904 st->cr(); 905 return; 906 } 907 } 908 nmethod* nm = b->as_nmethod_or_null(); 909 if (nm != NULL) { 910 ResourceMark rm; 911 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 912 addr, (int)(addr - nm->entry_point()), nm); 913 if (verbose) { 914 st->print(" for "); 915 nm->method()->print_value_on(st); 916 } 917 st->cr(); 918 nm->print_nmethod(verbose); 919 return; 920 } 921 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 922 b->print_on(st); 923 return; 924 } 925 926 if (Universe::heap()->is_in(addr)) { 927 HeapWord* p = Universe::heap()->block_start(addr); 928 bool print = false; 929 // If we couldn't find it it just may mean that heap wasn't parseable 930 // See if we were just given an oop directly 931 if (p != NULL && Universe::heap()->block_is_obj(p)) { 932 print = true; 933 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 934 p = (HeapWord*) addr; 935 print = true; 936 } 937 if (print) { 938 if (p == (HeapWord*) addr) { 939 st->print_cr(INTPTR_FORMAT " is an oop", addr); 940 } else { 941 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 942 } 943 oop(p)->print_on(st); 944 return; 945 } 946 } else { 947 if (Universe::heap()->is_in_reserved(addr)) { 948 st->print_cr(INTPTR_FORMAT " is an unallocated location " 949 "in the heap", addr); 950 return; 951 } 952 } 953 if (JNIHandles::is_global_handle((jobject) addr)) { 954 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 955 return; 956 } 957 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 958 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 959 return; 960 } 961 #ifndef PRODUCT 962 // we don't keep the block list in product mode 963 if (JNIHandleBlock::any_contains((jobject) addr)) { 964 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 965 return; 966 } 967 #endif 968 969 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 970 // Check for privilege stack 971 if (thread->privileged_stack_top() != NULL && 972 thread->privileged_stack_top()->contains(addr)) { 973 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 974 "for thread: " INTPTR_FORMAT, addr, thread); 975 if (verbose) thread->print_on(st); 976 return; 977 } 978 // If the addr is a java thread print information about that. 979 if (addr == (address)thread) { 980 if (verbose) { 981 thread->print_on(st); 982 } else { 983 st->print_cr(INTPTR_FORMAT " is a thread", addr); 984 } 985 return; 986 } 987 // If the addr is in the stack region for this thread then report that 988 // and print thread info 989 if (thread->stack_base() >= addr && 990 addr > (thread->stack_base() - thread->stack_size())) { 991 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 992 INTPTR_FORMAT, addr, thread); 993 if (verbose) thread->print_on(st); 994 return; 995 } 996 997 } 998 999 #ifndef PRODUCT 1000 // Check if in metaspace. 1001 if (ClassLoaderDataGraph::contains((address)addr)) { 1002 // Use addr->print() from the debugger instead (not here) 1003 st->print_cr(INTPTR_FORMAT 1004 " is pointing into metadata", addr); 1005 return; 1006 } 1007 #endif 1008 1009 // Try an OS specific find 1010 if (os::find(addr, st)) { 1011 return; 1012 } 1013 1014 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1015 } 1016 1017 // Looks like all platforms except IA64 can use the same function to check 1018 // if C stack is walkable beyond current frame. The check for fp() is not 1019 // necessary on Sparc, but it's harmless. 1020 bool os::is_first_C_frame(frame* fr) { 1021 #if defined(IA64) && !defined(_WIN32) 1022 // On IA64 we have to check if the callers bsp is still valid 1023 // (i.e. within the register stack bounds). 1024 // Notice: this only works for threads created by the VM and only if 1025 // we walk the current stack!!! If we want to be able to walk 1026 // arbitrary other threads, we'll have to somehow store the thread 1027 // object in the frame. 1028 Thread *thread = Thread::current(); 1029 if ((address)fr->fp() <= 1030 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1031 // This check is a little hacky, because on Linux the first C 1032 // frame's ('start_thread') register stack frame starts at 1033 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1034 // ('__pthread_bound_body') register stack frame seems to really 1035 // start at "register_stack_base". 1036 return true; 1037 } else { 1038 return false; 1039 } 1040 #elif defined(IA64) && defined(_WIN32) 1041 return true; 1042 #else 1043 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1044 // Check usp first, because if that's bad the other accessors may fault 1045 // on some architectures. Ditto ufp second, etc. 1046 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1047 // sp on amd can be 32 bit aligned. 1048 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1049 1050 uintptr_t usp = (uintptr_t)fr->sp(); 1051 if ((usp & sp_align_mask) != 0) return true; 1052 1053 uintptr_t ufp = (uintptr_t)fr->fp(); 1054 if ((ufp & fp_align_mask) != 0) return true; 1055 1056 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1057 if ((old_sp & sp_align_mask) != 0) return true; 1058 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1059 1060 uintptr_t old_fp = (uintptr_t)fr->link(); 1061 if ((old_fp & fp_align_mask) != 0) return true; 1062 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1063 1064 // stack grows downwards; if old_fp is below current fp or if the stack 1065 // frame is too large, either the stack is corrupted or fp is not saved 1066 // on stack (i.e. on x86, ebp may be used as general register). The stack 1067 // is not walkable beyond current frame. 1068 if (old_fp < ufp) return true; 1069 if (old_fp - ufp > 64 * K) return true; 1070 1071 return false; 1072 #endif 1073 } 1074 1075 #ifdef ASSERT 1076 extern "C" void test_random() { 1077 const double m = 2147483647; 1078 double mean = 0.0, variance = 0.0, t; 1079 long reps = 10000; 1080 unsigned long seed = 1; 1081 1082 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1083 os::init_random(seed); 1084 long num; 1085 for (int k = 0; k < reps; k++) { 1086 num = os::random(); 1087 double u = (double)num / m; 1088 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1089 1090 // calculate mean and variance of the random sequence 1091 mean += u; 1092 variance += (u*u); 1093 } 1094 mean /= reps; 1095 variance /= (reps - 1); 1096 1097 assert(num == 1043618065, "bad seed"); 1098 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1099 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1100 const double eps = 0.0001; 1101 t = fabsd(mean - 0.5018); 1102 assert(t < eps, "bad mean"); 1103 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1104 assert(t < eps, "bad variance"); 1105 } 1106 #endif 1107 1108 1109 // Set up the boot classpath. 1110 1111 char* os::format_boot_path(const char* format_string, 1112 const char* home, 1113 int home_len, 1114 char fileSep, 1115 char pathSep) { 1116 assert((fileSep == '/' && pathSep == ':') || 1117 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1118 1119 // Scan the format string to determine the length of the actual 1120 // boot classpath, and handle platform dependencies as well. 1121 int formatted_path_len = 0; 1122 const char* p; 1123 for (p = format_string; *p != 0; ++p) { 1124 if (*p == '%') formatted_path_len += home_len - 1; 1125 ++formatted_path_len; 1126 } 1127 1128 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1129 if (formatted_path == NULL) { 1130 return NULL; 1131 } 1132 1133 // Create boot classpath from format, substituting separator chars and 1134 // java home directory. 1135 char* q = formatted_path; 1136 for (p = format_string; *p != 0; ++p) { 1137 switch (*p) { 1138 case '%': 1139 strcpy(q, home); 1140 q += home_len; 1141 break; 1142 case '/': 1143 *q++ = fileSep; 1144 break; 1145 case ':': 1146 *q++ = pathSep; 1147 break; 1148 default: 1149 *q++ = *p; 1150 } 1151 } 1152 *q = '\0'; 1153 1154 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1155 return formatted_path; 1156 } 1157 1158 1159 bool os::set_boot_path(char fileSep, char pathSep) { 1160 const char* home = Arguments::get_java_home(); 1161 int home_len = (int)strlen(home); 1162 1163 static const char* meta_index_dir_format = "%/lib/"; 1164 static const char* meta_index_format = "%/lib/meta-index"; 1165 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1166 if (meta_index == NULL) return false; 1167 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1168 if (meta_index_dir == NULL) return false; 1169 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1170 1171 // Any modification to the JAR-file list, for the boot classpath must be 1172 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1173 // path class JARs, are stripped for StackMapTable to reduce download size. 1174 static const char classpath_format[] = 1175 "%/lib/resources.jar:" 1176 "%/lib/rt.jar:" 1177 "%/lib/sunrsasign.jar:" 1178 "%/lib/jsse.jar:" 1179 "%/lib/jce.jar:" 1180 "%/lib/charsets.jar:" 1181 "%/lib/jfr.jar:" 1182 #ifdef __APPLE__ 1183 "%/lib/JObjC.jar:" 1184 #endif 1185 "%/classes"; 1186 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1187 if (sysclasspath == NULL) return false; 1188 Arguments::set_sysclasspath(sysclasspath); 1189 1190 return true; 1191 } 1192 1193 /* 1194 * Splits a path, based on its separator, the number of 1195 * elements is returned back in n. 1196 * It is the callers responsibility to: 1197 * a> check the value of n, and n may be 0. 1198 * b> ignore any empty path elements 1199 * c> free up the data. 1200 */ 1201 char** os::split_path(const char* path, int* n) { 1202 *n = 0; 1203 if (path == NULL || strlen(path) == 0) { 1204 return NULL; 1205 } 1206 const char psepchar = *os::path_separator(); 1207 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1208 if (inpath == NULL) { 1209 return NULL; 1210 } 1211 strcpy(inpath, path); 1212 int count = 1; 1213 char* p = strchr(inpath, psepchar); 1214 // Get a count of elements to allocate memory 1215 while (p != NULL) { 1216 count++; 1217 p++; 1218 p = strchr(p, psepchar); 1219 } 1220 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1221 if (opath == NULL) { 1222 return NULL; 1223 } 1224 1225 // do the actual splitting 1226 p = inpath; 1227 for (int i = 0 ; i < count ; i++) { 1228 size_t len = strcspn(p, os::path_separator()); 1229 if (len > JVM_MAXPATHLEN) { 1230 return NULL; 1231 } 1232 // allocate the string and add terminator storage 1233 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1234 if (s == NULL) { 1235 return NULL; 1236 } 1237 strncpy(s, p, len); 1238 s[len] = '\0'; 1239 opath[i] = s; 1240 p += len + 1; 1241 } 1242 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1243 *n = count; 1244 return opath; 1245 } 1246 1247 void os::set_memory_serialize_page(address page) { 1248 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1249 _mem_serialize_page = (volatile int32_t *)page; 1250 // We initialize the serialization page shift count here 1251 // We assume a cache line size of 64 bytes 1252 assert(SerializePageShiftCount == count, 1253 "thread size changed, fix SerializePageShiftCount constant"); 1254 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1255 } 1256 1257 static volatile intptr_t SerializePageLock = 0; 1258 1259 // This method is called from signal handler when SIGSEGV occurs while the current 1260 // thread tries to store to the "read-only" memory serialize page during state 1261 // transition. 1262 void os::block_on_serialize_page_trap() { 1263 if (TraceSafepoint) { 1264 tty->print_cr("Block until the serialize page permission restored"); 1265 } 1266 // When VMThread is holding the SerializePageLock during modifying the 1267 // access permission of the memory serialize page, the following call 1268 // will block until the permission of that page is restored to rw. 1269 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1270 // this case, it's OK as the signal is synchronous and we know precisely when 1271 // it can occur. 1272 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1273 Thread::muxRelease(&SerializePageLock); 1274 } 1275 1276 // Serialize all thread state variables 1277 void os::serialize_thread_states() { 1278 // On some platforms such as Solaris & Linux, the time duration of the page 1279 // permission restoration is observed to be much longer than expected due to 1280 // scheduler starvation problem etc. To avoid the long synchronization 1281 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1282 // the mutator thread if such case is encountered. See bug 6546278 for details. 1283 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1284 os::protect_memory((char *)os::get_memory_serialize_page(), 1285 os::vm_page_size(), MEM_PROT_READ); 1286 os::protect_memory((char *)os::get_memory_serialize_page(), 1287 os::vm_page_size(), MEM_PROT_RW); 1288 Thread::muxRelease(&SerializePageLock); 1289 } 1290 1291 // Returns true if the current stack pointer is above the stack shadow 1292 // pages, false otherwise. 1293 1294 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1295 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1296 address sp = current_stack_pointer(); 1297 // Check if we have StackShadowPages above the yellow zone. This parameter 1298 // is dependent on the depth of the maximum VM call stack possible from 1299 // the handler for stack overflow. 'instanceof' in the stack overflow 1300 // handler or a println uses at least 8k stack of VM and native code 1301 // respectively. 1302 const int framesize_in_bytes = 1303 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1304 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1305 * vm_page_size()) + framesize_in_bytes; 1306 // The very lower end of the stack 1307 address stack_limit = thread->stack_base() - thread->stack_size(); 1308 return (sp > (stack_limit + reserved_area)); 1309 } 1310 1311 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1312 uint min_pages) 1313 { 1314 assert(min_pages > 0, "sanity"); 1315 if (UseLargePages) { 1316 const size_t max_page_size = region_max_size / min_pages; 1317 1318 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1319 const size_t sz = _page_sizes[i]; 1320 const size_t mask = sz - 1; 1321 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1322 // The largest page size with no fragmentation. 1323 return sz; 1324 } 1325 1326 if (sz <= max_page_size) { 1327 // The largest page size that satisfies the min_pages requirement. 1328 return sz; 1329 } 1330 } 1331 } 1332 1333 return vm_page_size(); 1334 } 1335 1336 #ifndef PRODUCT 1337 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1338 { 1339 if (TracePageSizes) { 1340 tty->print("%s: ", str); 1341 for (int i = 0; i < count; ++i) { 1342 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1343 } 1344 tty->cr(); 1345 } 1346 } 1347 1348 void os::trace_page_sizes(const char* str, const size_t region_min_size, 1349 const size_t region_max_size, const size_t page_size, 1350 const char* base, const size_t size) 1351 { 1352 if (TracePageSizes) { 1353 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1354 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1355 " size=" SIZE_FORMAT, 1356 str, region_min_size, region_max_size, 1357 page_size, base, size); 1358 } 1359 } 1360 #endif // #ifndef PRODUCT 1361 1362 // This is the working definition of a server class machine: 1363 // >= 2 physical CPU's and >=2GB of memory, with some fuzz 1364 // because the graphics memory (?) sometimes masks physical memory. 1365 // If you want to change the definition of a server class machine 1366 // on some OS or platform, e.g., >=4GB on Windohs platforms, 1367 // then you'll have to parameterize this method based on that state, 1368 // as was done for logical processors here, or replicate and 1369 // specialize this method for each platform. (Or fix os to have 1370 // some inheritance structure and use subclassing. Sigh.) 1371 // If you want some platform to always or never behave as a server 1372 // class machine, change the setting of AlwaysActAsServerClassMachine 1373 // and NeverActAsServerClassMachine in globals*.hpp. 1374 bool os::is_server_class_machine() { 1375 // First check for the early returns 1376 if (NeverActAsServerClassMachine) { 1377 return false; 1378 } 1379 if (AlwaysActAsServerClassMachine) { 1380 return true; 1381 } 1382 // Then actually look at the machine 1383 bool result = false; 1384 const unsigned int server_processors = 2; 1385 const julong server_memory = 2UL * G; 1386 // We seem not to get our full complement of memory. 1387 // We allow some part (1/8?) of the memory to be "missing", 1388 // based on the sizes of DIMMs, and maybe graphics cards. 1389 const julong missing_memory = 256UL * M; 1390 1391 /* Is this a server class machine? */ 1392 if ((os::active_processor_count() >= (int)server_processors) && 1393 (os::physical_memory() >= (server_memory - missing_memory))) { 1394 const unsigned int logical_processors = 1395 VM_Version::logical_processors_per_package(); 1396 if (logical_processors > 1) { 1397 const unsigned int physical_packages = 1398 os::active_processor_count() / logical_processors; 1399 if (physical_packages > server_processors) { 1400 result = true; 1401 } 1402 } else { 1403 result = true; 1404 } 1405 } 1406 return result; 1407 } 1408 1409 // Read file line by line, if line is longer than bsize, 1410 // skip rest of line. 1411 int os::get_line_chars(int fd, char* buf, const size_t bsize){ 1412 size_t sz, i = 0; 1413 1414 // read until EOF, EOL or buf is full 1415 while ((sz = (int) read(fd, &buf[i], 1)) == 1 && i < (bsize-2) && buf[i] != '\n') { 1416 ++i; 1417 } 1418 1419 if (buf[i] == '\n') { 1420 // EOL reached so ignore EOL character and return 1421 1422 buf[i] = 0; 1423 return (int) i; 1424 } 1425 1426 buf[i+1] = 0; 1427 1428 if (sz != 1) { 1429 // EOF reached. if we read chars before EOF return them and 1430 // return EOF on next call otherwise return EOF 1431 1432 return (i == 0) ? -1 : (int) i; 1433 } 1434 1435 // line is longer than size of buf, skip to EOL 1436 char ch; 1437 while (read(fd, &ch, 1) == 1 && ch != '\n') { 1438 // Do nothing 1439 } 1440 1441 // return initial part of line that fits in buf. 1442 // If we reached EOF, it will be returned on next call. 1443 1444 return (int) i; 1445 } 1446 1447 bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1448 return os::pd_create_stack_guard_pages(addr, bytes); 1449 } 1450 1451 1452 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1453 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1454 if (result != NULL) { 1455 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1456 } 1457 1458 return result; 1459 } 1460 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1461 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1462 if (result != NULL) { 1463 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1464 } 1465 return result; 1466 } 1467 1468 void os::split_reserved_memory(char *base, size_t size, 1469 size_t split, bool realloc) { 1470 pd_split_reserved_memory(base, size, split, realloc); 1471 } 1472 1473 bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1474 bool res = pd_commit_memory(addr, bytes, executable); 1475 if (res) { 1476 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1477 } 1478 return res; 1479 } 1480 1481 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1482 bool executable) { 1483 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1484 if (res) { 1485 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1486 } 1487 return res; 1488 } 1489 1490 bool os::uncommit_memory(char* addr, size_t bytes) { 1491 bool res = pd_uncommit_memory(addr, bytes); 1492 if (res) { 1493 MemTracker::record_virtual_memory_uncommit((address)addr, bytes); 1494 } 1495 return res; 1496 } 1497 1498 bool os::release_memory(char* addr, size_t bytes) { 1499 bool res = pd_release_memory(addr, bytes); 1500 if (res) { 1501 MemTracker::record_virtual_memory_release((address)addr, bytes); 1502 } 1503 return res; 1504 } 1505 1506 1507 char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1508 char *addr, size_t bytes, bool read_only, 1509 bool allow_exec) { 1510 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1511 if (result != NULL) { 1512 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1513 MemTracker::record_virtual_memory_commit((address)result, bytes, CALLER_PC); 1514 } 1515 return result; 1516 } 1517 1518 char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1519 char *addr, size_t bytes, bool read_only, 1520 bool allow_exec) { 1521 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1522 read_only, allow_exec); 1523 } 1524 1525 bool os::unmap_memory(char *addr, size_t bytes) { 1526 bool result = pd_unmap_memory(addr, bytes); 1527 if (result) { 1528 MemTracker::record_virtual_memory_uncommit((address)addr, bytes); 1529 MemTracker::record_virtual_memory_release((address)addr, bytes); 1530 } 1531 return result; 1532 } 1533 1534 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1535 pd_free_memory(addr, bytes, alignment_hint); 1536 } 1537 1538 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1539 pd_realign_memory(addr, bytes, alignment_hint); 1540 } 1541