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