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