os.cpp revision 2767:436b4a3231bf
1/* 2 * Copyright (c) 1997, 2011, 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 "services/attachListener.hpp" 48#include "services/threadService.hpp" 49#include "utilities/defaultStream.hpp" 50#include "utilities/events.hpp" 51#ifdef TARGET_OS_FAMILY_linux 52# include "os_linux.inline.hpp" 53# include "thread_linux.inline.hpp" 54#endif 55#ifdef TARGET_OS_FAMILY_solaris 56# include "os_solaris.inline.hpp" 57# include "thread_solaris.inline.hpp" 58#endif 59#ifdef TARGET_OS_FAMILY_windows 60# include "os_windows.inline.hpp" 61# include "thread_windows.inline.hpp" 62#endif 63#ifdef TARGET_OS_FAMILY_bsd 64# include "os_bsd.inline.hpp" 65# include "thread_bsd.inline.hpp" 66#endif 67 68# include <signal.h> 69 70OSThread* os::_starting_thread = NULL; 71address os::_polling_page = NULL; 72volatile int32_t* os::_mem_serialize_page = NULL; 73uintptr_t os::_serialize_page_mask = 0; 74long os::_rand_seed = 1; 75int os::_processor_count = 0; 76size_t os::_page_sizes[os::page_sizes_max]; 77 78#ifndef PRODUCT 79julong os::num_mallocs = 0; // # of calls to malloc/realloc 80julong os::alloc_bytes = 0; // # of bytes allocated 81julong os::num_frees = 0; // # of calls to free 82julong os::free_bytes = 0; // # of bytes freed 83#endif 84 85// Fill in buffer with current local time as an ISO-8601 string. 86// E.g., yyyy-mm-ddThh:mm:ss-zzzz. 87// Returns buffer, or NULL if it failed. 88// This would mostly be a call to 89// strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 90// except that on Windows the %z behaves badly, so we do it ourselves. 91// Also, people wanted milliseconds on there, 92// and strftime doesn't do milliseconds. 93char* os::iso8601_time(char* buffer, size_t buffer_length) { 94 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 95 // 1 2 96 // 12345678901234567890123456789 97 static const char* iso8601_format = 98 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; 99 static const size_t needed_buffer = 29; 100 101 // Sanity check the arguments 102 if (buffer == NULL) { 103 assert(false, "NULL buffer"); 104 return NULL; 105 } 106 if (buffer_length < needed_buffer) { 107 assert(false, "buffer_length too small"); 108 return NULL; 109 } 110 // Get the current time 111 jlong milliseconds_since_19700101 = javaTimeMillis(); 112 const int milliseconds_per_microsecond = 1000; 113 const time_t seconds_since_19700101 = 114 milliseconds_since_19700101 / milliseconds_per_microsecond; 115 const int milliseconds_after_second = 116 milliseconds_since_19700101 % milliseconds_per_microsecond; 117 // Convert the time value to a tm and timezone variable 118 struct tm time_struct; 119 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 120 assert(false, "Failed localtime_pd"); 121 return NULL; 122 } 123#if defined(_ALLBSD_SOURCE) 124 const time_t zone = (time_t) time_struct.tm_gmtoff; 125#else 126 const time_t zone = timezone; 127#endif 128 129 // If daylight savings time is in effect, 130 // we are 1 hour East of our time zone 131 const time_t seconds_per_minute = 60; 132 const time_t minutes_per_hour = 60; 133 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 134 time_t UTC_to_local = zone; 135 if (time_struct.tm_isdst > 0) { 136 UTC_to_local = UTC_to_local - seconds_per_hour; 137 } 138 // Compute the time zone offset. 139 // localtime_pd() sets timezone to the difference (in seconds) 140 // between UTC and and local time. 141 // ISO 8601 says we need the difference between local time and UTC, 142 // we change the sign of the localtime_pd() result. 143 const time_t local_to_UTC = -(UTC_to_local); 144 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 145 char sign_local_to_UTC = '+'; 146 time_t abs_local_to_UTC = local_to_UTC; 147 if (local_to_UTC < 0) { 148 sign_local_to_UTC = '-'; 149 abs_local_to_UTC = -(abs_local_to_UTC); 150 } 151 // Convert time zone offset seconds to hours and minutes. 152 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 153 const time_t zone_min = 154 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 155 156 // Print an ISO 8601 date and time stamp into the buffer 157 const int year = 1900 + time_struct.tm_year; 158 const int month = 1 + time_struct.tm_mon; 159 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, 160 year, 161 month, 162 time_struct.tm_mday, 163 time_struct.tm_hour, 164 time_struct.tm_min, 165 time_struct.tm_sec, 166 milliseconds_after_second, 167 sign_local_to_UTC, 168 zone_hours, 169 zone_min); 170 if (printed == 0) { 171 assert(false, "Failed jio_printf"); 172 return NULL; 173 } 174 return buffer; 175} 176 177OSReturn os::set_priority(Thread* thread, ThreadPriority p) { 178#ifdef ASSERT 179 if (!(!thread->is_Java_thread() || 180 Thread::current() == thread || 181 Threads_lock->owned_by_self() 182 || thread->is_Compiler_thread() 183 )) { 184 assert(false, "possibility of dangling Thread pointer"); 185 } 186#endif 187 188 if (p >= MinPriority && p <= MaxPriority) { 189 int priority = java_to_os_priority[p]; 190 return set_native_priority(thread, priority); 191 } else { 192 assert(false, "Should not happen"); 193 return OS_ERR; 194 } 195} 196 197 198OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 199 int p; 200 int os_prio; 201 OSReturn ret = get_native_priority(thread, &os_prio); 202 if (ret != OS_OK) return ret; 203 204 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 205 priority = (ThreadPriority)p; 206 return OS_OK; 207} 208 209 210// --------------------- sun.misc.Signal (optional) --------------------- 211 212 213// SIGBREAK is sent by the keyboard to query the VM state 214#ifndef SIGBREAK 215#define SIGBREAK SIGQUIT 216#endif 217 218// sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 219 220 221static void signal_thread_entry(JavaThread* thread, TRAPS) { 222 os::set_priority(thread, NearMaxPriority); 223 while (true) { 224 int sig; 225 { 226 // FIXME : Currently we have not decieded what should be the status 227 // for this java thread blocked here. Once we decide about 228 // that we should fix this. 229 sig = os::signal_wait(); 230 } 231 if (sig == os::sigexitnum_pd()) { 232 // Terminate the signal thread 233 return; 234 } 235 236 switch (sig) { 237 case SIGBREAK: { 238 // Check if the signal is a trigger to start the Attach Listener - in that 239 // case don't print stack traces. 240 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 241 continue; 242 } 243 // Print stack traces 244 // Any SIGBREAK operations added here should make sure to flush 245 // the output stream (e.g. tty->flush()) after output. See 4803766. 246 // Each module also prints an extra carriage return after its output. 247 VM_PrintThreads op; 248 VMThread::execute(&op); 249 VM_PrintJNI jni_op; 250 VMThread::execute(&jni_op); 251 VM_FindDeadlocks op1(tty); 252 VMThread::execute(&op1); 253 Universe::print_heap_at_SIGBREAK(); 254 if (PrintClassHistogram) { 255 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */, 256 true /* need_prologue */); 257 VMThread::execute(&op1); 258 } 259 if (JvmtiExport::should_post_data_dump()) { 260 JvmtiExport::post_data_dump(); 261 } 262 break; 263 } 264 default: { 265 // Dispatch the signal to java 266 HandleMark hm(THREAD); 267 klassOop k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 268 KlassHandle klass (THREAD, k); 269 if (klass.not_null()) { 270 JavaValue result(T_VOID); 271 JavaCallArguments args; 272 args.push_int(sig); 273 JavaCalls::call_static( 274 &result, 275 klass, 276 vmSymbols::dispatch_name(), 277 vmSymbols::int_void_signature(), 278 &args, 279 THREAD 280 ); 281 } 282 if (HAS_PENDING_EXCEPTION) { 283 // tty is initialized early so we don't expect it to be null, but 284 // if it is we can't risk doing an initialization that might 285 // trigger additional out-of-memory conditions 286 if (tty != NULL) { 287 char klass_name[256]; 288 char tmp_sig_name[16]; 289 const char* sig_name = "UNKNOWN"; 290 instanceKlass::cast(PENDING_EXCEPTION->klass())-> 291 name()->as_klass_external_name(klass_name, 256); 292 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 293 sig_name = tmp_sig_name; 294 warning("Exception %s occurred dispatching signal %s to handler" 295 "- the VM may need to be forcibly terminated", 296 klass_name, sig_name ); 297 } 298 CLEAR_PENDING_EXCEPTION; 299 } 300 } 301 } 302 } 303} 304 305 306void os::signal_init() { 307 if (!ReduceSignalUsage) { 308 // Setup JavaThread for processing signals 309 EXCEPTION_MARK; 310 klassOop k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 311 instanceKlassHandle klass (THREAD, k); 312 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 313 314 const char thread_name[] = "Signal Dispatcher"; 315 Handle string = java_lang_String::create_from_str(thread_name, CHECK); 316 317 // Initialize thread_oop to put it into the system threadGroup 318 Handle thread_group (THREAD, Universe::system_thread_group()); 319 JavaValue result(T_VOID); 320 JavaCalls::call_special(&result, thread_oop, 321 klass, 322 vmSymbols::object_initializer_name(), 323 vmSymbols::threadgroup_string_void_signature(), 324 thread_group, 325 string, 326 CHECK); 327 328 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 329 JavaCalls::call_special(&result, 330 thread_group, 331 group, 332 vmSymbols::add_method_name(), 333 vmSymbols::thread_void_signature(), 334 thread_oop, // ARG 1 335 CHECK); 336 337 os::signal_init_pd(); 338 339 { MutexLocker mu(Threads_lock); 340 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 341 342 // At this point it may be possible that no osthread was created for the 343 // JavaThread due to lack of memory. We would have to throw an exception 344 // in that case. However, since this must work and we do not allow 345 // exceptions anyway, check and abort if this fails. 346 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 347 vm_exit_during_initialization("java.lang.OutOfMemoryError", 348 "unable to create new native thread"); 349 } 350 351 java_lang_Thread::set_thread(thread_oop(), signal_thread); 352 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 353 java_lang_Thread::set_daemon(thread_oop()); 354 355 signal_thread->set_threadObj(thread_oop()); 356 Threads::add(signal_thread); 357 Thread::start(signal_thread); 358 } 359 // Handle ^BREAK 360 os::signal(SIGBREAK, os::user_handler()); 361 } 362} 363 364 365void os::terminate_signal_thread() { 366 if (!ReduceSignalUsage) 367 signal_notify(sigexitnum_pd()); 368} 369 370 371// --------------------- loading libraries --------------------- 372 373typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 374extern struct JavaVM_ main_vm; 375 376static void* _native_java_library = NULL; 377 378void* os::native_java_library() { 379 if (_native_java_library == NULL) { 380 char buffer[JVM_MAXPATHLEN]; 381 char ebuf[1024]; 382 383 // Try to load verify dll first. In 1.3 java dll depends on it and is not 384 // always able to find it when the loading executable is outside the JDK. 385 // In order to keep working with 1.2 we ignore any loading errors. 386 dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), "verify"); 387 dll_load(buffer, ebuf, sizeof(ebuf)); 388 389 // Load java dll 390 dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), "java"); 391 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 392 if (_native_java_library == NULL) { 393 vm_exit_during_initialization("Unable to load native library", ebuf); 394 } 395 396#if defined(__OpenBSD__) 397 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 398 // ignore errors 399 dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), "net"); 400 dll_load(buffer, ebuf, sizeof(ebuf)); 401#endif 402 } 403 static jboolean onLoaded = JNI_FALSE; 404 if (onLoaded) { 405 // We may have to wait to fire OnLoad until TLS is initialized. 406 if (ThreadLocalStorage::is_initialized()) { 407 // The JNI_OnLoad handling is normally done by method load in 408 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 409 // explicitly so we have to check for JNI_OnLoad as well 410 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 411 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 412 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 413 if (JNI_OnLoad != NULL) { 414 JavaThread* thread = JavaThread::current(); 415 ThreadToNativeFromVM ttn(thread); 416 HandleMark hm(thread); 417 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 418 onLoaded = JNI_TRUE; 419 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 420 vm_exit_during_initialization("Unsupported JNI version"); 421 } 422 } 423 } 424 } 425 return _native_java_library; 426} 427 428// --------------------- heap allocation utilities --------------------- 429 430char *os::strdup(const char *str) { 431 size_t size = strlen(str); 432 char *dup_str = (char *)malloc(size + 1); 433 if (dup_str == NULL) return NULL; 434 strcpy(dup_str, str); 435 return dup_str; 436} 437 438 439 440#ifdef ASSERT 441#define space_before (MallocCushion + sizeof(double)) 442#define space_after MallocCushion 443#define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) 444#define size_addr_from_obj(p) ((size_t*)p - 1) 445// MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly 446// NB: cannot be debug variable, because these aren't set from the command line until 447// *after* the first few allocs already happened 448#define MallocCushion 16 449#else 450#define space_before 0 451#define space_after 0 452#define size_addr_from_base(p) should not use w/o ASSERT 453#define size_addr_from_obj(p) should not use w/o ASSERT 454#define MallocCushion 0 455#endif 456#define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 457 458#ifdef ASSERT 459inline size_t get_size(void* obj) { 460 size_t size = *size_addr_from_obj(obj); 461 if (size < 0) { 462 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten (" 463 SIZE_FORMAT ")", obj, size)); 464 } 465 return size; 466} 467 468u_char* find_cushion_backwards(u_char* start) { 469 u_char* p = start; 470 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || 471 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; 472 // ok, we have four consecutive marker bytes; find start 473 u_char* q = p - 4; 474 while (*q == badResourceValue) q--; 475 return q + 1; 476} 477 478u_char* find_cushion_forwards(u_char* start) { 479 u_char* p = start; 480 while (p[0] != badResourceValue || p[1] != badResourceValue || 481 p[2] != badResourceValue || p[3] != badResourceValue) p++; 482 // ok, we have four consecutive marker bytes; find end of cushion 483 u_char* q = p + 4; 484 while (*q == badResourceValue) q++; 485 return q - MallocCushion; 486} 487 488void print_neighbor_blocks(void* ptr) { 489 // find block allocated before ptr (not entirely crash-proof) 490 if (MallocCushion < 4) { 491 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); 492 return; 493 } 494 u_char* start_of_this_block = (u_char*)ptr - space_before; 495 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; 496 // look for cushion in front of prev. block 497 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); 498 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); 499 u_char* obj = start_of_prev_block + space_before; 500 if (size <= 0 ) { 501 // start is bad; mayhave been confused by OS data inbetween objects 502 // search one more backwards 503 start_of_prev_block = find_cushion_backwards(start_of_prev_block); 504 size = *size_addr_from_base(start_of_prev_block); 505 obj = start_of_prev_block + space_before; 506 } 507 508 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { 509 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 510 } else { 511 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 512 } 513 514 // now find successor block 515 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; 516 start_of_next_block = find_cushion_forwards(start_of_next_block); 517 u_char* next_obj = start_of_next_block + space_before; 518 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); 519 if (start_of_next_block[0] == badResourceValue && 520 start_of_next_block[1] == badResourceValue && 521 start_of_next_block[2] == badResourceValue && 522 start_of_next_block[3] == badResourceValue) { 523 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 524 } else { 525 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 526 } 527} 528 529 530void report_heap_error(void* memblock, void* bad, const char* where) { 531 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 532 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock); 533 print_neighbor_blocks(memblock); 534 fatal("memory stomping error"); 535} 536 537void verify_block(void* memblock) { 538 size_t size = get_size(memblock); 539 if (MallocCushion) { 540 u_char* ptr = (u_char*)memblock - space_before; 541 for (int i = 0; i < MallocCushion; i++) { 542 if (ptr[i] != badResourceValue) { 543 report_heap_error(memblock, ptr+i, "in front of"); 544 } 545 } 546 u_char* end = (u_char*)memblock + size + space_after; 547 for (int j = -MallocCushion; j < 0; j++) { 548 if (end[j] != badResourceValue) { 549 report_heap_error(memblock, end+j, "after"); 550 } 551 } 552 } 553} 554#endif 555 556void* os::malloc(size_t size) { 557 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 558 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 559 560 if (size == 0) { 561 // return a valid pointer if size is zero 562 // if NULL is returned the calling functions assume out of memory. 563 size = 1; 564 } 565 566 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 567 u_char* ptr = (u_char*)::malloc(size + space_before + space_after); 568#ifdef ASSERT 569 if (ptr == NULL) return NULL; 570 if (MallocCushion) { 571 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; 572 u_char* end = ptr + space_before + size; 573 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; 574 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; 575 } 576 // put size just before data 577 *size_addr_from_base(ptr) = size; 578#endif 579 u_char* memblock = ptr + space_before; 580 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 581 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 582 breakpoint(); 583 } 584 debug_only(if (paranoid) verify_block(memblock)); 585 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 586 return memblock; 587} 588 589 590void* os::realloc(void *memblock, size_t size) { 591#ifndef ASSERT 592 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 593 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 594 return ::realloc(memblock, size); 595#else 596 if (memblock == NULL) { 597 return malloc(size); 598 } 599 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 600 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 601 breakpoint(); 602 } 603 verify_block(memblock); 604 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 605 if (size == 0) return NULL; 606 // always move the block 607 void* ptr = malloc(size); 608 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 609 // Copy to new memory if malloc didn't fail 610 if ( ptr != NULL ) { 611 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); 612 if (paranoid) verify_block(ptr); 613 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 614 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 615 breakpoint(); 616 } 617 free(memblock); 618 } 619 return ptr; 620#endif 621} 622 623 624void os::free(void *memblock) { 625 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 626#ifdef ASSERT 627 if (memblock == NULL) return; 628 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 629 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 630 breakpoint(); 631 } 632 verify_block(memblock); 633 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 634 // Added by detlefs. 635 if (MallocCushion) { 636 u_char* ptr = (u_char*)memblock - space_before; 637 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { 638 guarantee(*p == badResourceValue, 639 "Thing freed should be malloc result."); 640 *p = (u_char)freeBlockPad; 641 } 642 size_t size = get_size(memblock); 643 inc_stat_counter(&free_bytes, size); 644 u_char* end = ptr + space_before + size; 645 for (u_char* q = end; q < end + MallocCushion; q++) { 646 guarantee(*q == badResourceValue, 647 "Thing freed should be malloc result."); 648 *q = (u_char)freeBlockPad; 649 } 650 if (PrintMalloc && tty != NULL) 651 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 652 } else if (PrintMalloc && tty != NULL) { 653 // tty->print_cr("os::free %p", memblock); 654 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock); 655 } 656#endif 657 ::free((char*)memblock - space_before); 658} 659 660void os::init_random(long initval) { 661 _rand_seed = initval; 662} 663 664 665long os::random() { 666 /* standard, well-known linear congruential random generator with 667 * next_rand = (16807*seed) mod (2**31-1) 668 * see 669 * (1) "Random Number Generators: Good Ones Are Hard to Find", 670 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 671 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 672 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 673 */ 674 const long a = 16807; 675 const unsigned long m = 2147483647; 676 const long q = m / a; assert(q == 127773, "weird math"); 677 const long r = m % a; assert(r == 2836, "weird math"); 678 679 // compute az=2^31p+q 680 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 681 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 682 lo += (hi & 0x7FFF) << 16; 683 684 // if q overflowed, ignore the overflow and increment q 685 if (lo > m) { 686 lo &= m; 687 ++lo; 688 } 689 lo += hi >> 15; 690 691 // if (p+q) overflowed, ignore the overflow and increment (p+q) 692 if (lo > m) { 693 lo &= m; 694 ++lo; 695 } 696 return (_rand_seed = lo); 697} 698 699// The INITIALIZED state is distinguished from the SUSPENDED state because the 700// conditions in which a thread is first started are different from those in which 701// a suspension is resumed. These differences make it hard for us to apply the 702// tougher checks when starting threads that we want to do when resuming them. 703// However, when start_thread is called as a result of Thread.start, on a Java 704// thread, the operation is synchronized on the Java Thread object. So there 705// cannot be a race to start the thread and hence for the thread to exit while 706// we are working on it. Non-Java threads that start Java threads either have 707// to do so in a context in which races are impossible, or should do appropriate 708// locking. 709 710void os::start_thread(Thread* thread) { 711 // guard suspend/resume 712 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 713 OSThread* osthread = thread->osthread(); 714 osthread->set_state(RUNNABLE); 715 pd_start_thread(thread); 716} 717 718//--------------------------------------------------------------------------- 719// Helper functions for fatal error handler 720 721void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 722 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 723 724 int cols = 0; 725 int cols_per_line = 0; 726 switch (unitsize) { 727 case 1: cols_per_line = 16; break; 728 case 2: cols_per_line = 8; break; 729 case 4: cols_per_line = 4; break; 730 case 8: cols_per_line = 2; break; 731 default: return; 732 } 733 734 address p = start; 735 st->print(PTR_FORMAT ": ", start); 736 while (p < end) { 737 switch (unitsize) { 738 case 1: st->print("%02x", *(u1*)p); break; 739 case 2: st->print("%04x", *(u2*)p); break; 740 case 4: st->print("%08x", *(u4*)p); break; 741 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 742 } 743 p += unitsize; 744 cols++; 745 if (cols >= cols_per_line && p < end) { 746 cols = 0; 747 st->cr(); 748 st->print(PTR_FORMAT ": ", p); 749 } else { 750 st->print(" "); 751 } 752 } 753 st->cr(); 754} 755 756void os::print_environment_variables(outputStream* st, const char** env_list, 757 char* buffer, int len) { 758 if (env_list) { 759 st->print_cr("Environment Variables:"); 760 761 for (int i = 0; env_list[i] != NULL; i++) { 762 if (getenv(env_list[i], buffer, len)) { 763 st->print(env_list[i]); 764 st->print("="); 765 st->print_cr(buffer); 766 } 767 } 768 } 769} 770 771void os::print_cpu_info(outputStream* st) { 772 // cpu 773 st->print("CPU:"); 774 st->print("total %d", os::processor_count()); 775 // It's not safe to query number of active processors after crash 776 // st->print("(active %d)", os::active_processor_count()); 777 st->print(" %s", VM_Version::cpu_features()); 778 st->cr(); 779 pd_print_cpu_info(st); 780} 781 782void os::print_date_and_time(outputStream *st) { 783 time_t tloc; 784 (void)time(&tloc); 785 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 786 787 double t = os::elapsedTime(); 788 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 789 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 790 // before printf. We lost some precision, but who cares? 791 st->print_cr("elapsed time: %d seconds", (int)t); 792} 793 794// moved from debug.cpp (used to be find()) but still called from there 795// The verbose parameter is only set by the debug code in one case 796void os::print_location(outputStream* st, intptr_t x, bool verbose) { 797 address addr = (address)x; 798 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 799 if (b != NULL) { 800 if (b->is_buffer_blob()) { 801 // the interpreter is generated into a buffer blob 802 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 803 if (i != NULL) { 804 st->print_cr(INTPTR_FORMAT " is an Interpreter codelet", addr); 805 i->print_on(st); 806 return; 807 } 808 if (Interpreter::contains(addr)) { 809 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 810 " (not bytecode specific)", addr); 811 return; 812 } 813 // 814 if (AdapterHandlerLibrary::contains(b)) { 815 st->print_cr(INTPTR_FORMAT " is an AdapterHandler", addr); 816 AdapterHandlerLibrary::print_handler_on(st, b); 817 } 818 // the stubroutines are generated into a buffer blob 819 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 820 if (d != NULL) { 821 d->print_on(st); 822 if (verbose) st->cr(); 823 return; 824 } 825 if (StubRoutines::contains(addr)) { 826 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 827 "stub routine", addr); 828 return; 829 } 830 // the InlineCacheBuffer is using stubs generated into a buffer blob 831 if (InlineCacheBuffer::contains(addr)) { 832 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 833 return; 834 } 835 VtableStub* v = VtableStubs::stub_containing(addr); 836 if (v != NULL) { 837 v->print_on(st); 838 return; 839 } 840 } 841 if (verbose && b->is_nmethod()) { 842 ResourceMark rm; 843 st->print("%#p: Compiled ", addr); 844 ((nmethod*)b)->method()->print_value_on(st); 845 st->print(" = (CodeBlob*)" INTPTR_FORMAT, b); 846 st->cr(); 847 return; 848 } 849 st->print(INTPTR_FORMAT " ", b); 850 if ( b->is_nmethod()) { 851 if (b->is_zombie()) { 852 st->print_cr("is zombie nmethod"); 853 } else if (b->is_not_entrant()) { 854 st->print_cr("is non-entrant nmethod"); 855 } 856 } 857 b->print_on(st); 858 return; 859 } 860 861 if (Universe::heap()->is_in(addr)) { 862 HeapWord* p = Universe::heap()->block_start(addr); 863 bool print = false; 864 // If we couldn't find it it just may mean that heap wasn't parseable 865 // See if we were just given an oop directly 866 if (p != NULL && Universe::heap()->block_is_obj(p)) { 867 print = true; 868 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 869 p = (HeapWord*) addr; 870 print = true; 871 } 872 if (print) { 873 st->print_cr(INTPTR_FORMAT " is an oop", addr); 874 oop(p)->print_on(st); 875 if (p != (HeapWord*)x && oop(p)->is_constMethod() && 876 constMethodOop(p)->contains(addr)) { 877 Thread *thread = Thread::current(); 878 HandleMark hm(thread); 879 methodHandle mh (thread, constMethodOop(p)->method()); 880 if (!mh->is_native()) { 881 st->print_cr("bci_from(%p) = %d; print_codes():", 882 addr, mh->bci_from(address(x))); 883 mh->print_codes_on(st); 884 } 885 } 886 return; 887 } 888 } else { 889 if (Universe::heap()->is_in_reserved(addr)) { 890 st->print_cr(INTPTR_FORMAT " is an unallocated location " 891 "in the heap", addr); 892 return; 893 } 894 } 895 if (JNIHandles::is_global_handle((jobject) addr)) { 896 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 897 return; 898 } 899 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 900 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 901 return; 902 } 903#ifndef PRODUCT 904 // we don't keep the block list in product mode 905 if (JNIHandleBlock::any_contains((jobject) addr)) { 906 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 907 return; 908 } 909#endif 910 911 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 912 // Check for privilege stack 913 if (thread->privileged_stack_top() != NULL && 914 thread->privileged_stack_top()->contains(addr)) { 915 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 916 "for thread: " INTPTR_FORMAT, addr, thread); 917 if (verbose) thread->print_on(st); 918 return; 919 } 920 // If the addr is a java thread print information about that. 921 if (addr == (address)thread) { 922 if (verbose) { 923 thread->print_on(st); 924 } else { 925 st->print_cr(INTPTR_FORMAT " is a thread", addr); 926 } 927 return; 928 } 929 // If the addr is in the stack region for this thread then report that 930 // and print thread info 931 if (thread->stack_base() >= addr && 932 addr > (thread->stack_base() - thread->stack_size())) { 933 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 934 INTPTR_FORMAT, addr, thread); 935 if (verbose) thread->print_on(st); 936 return; 937 } 938 939 } 940 // Try an OS specific find 941 if (os::find(addr, st)) { 942 return; 943 } 944 945 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 946} 947 948// Looks like all platforms except IA64 can use the same function to check 949// if C stack is walkable beyond current frame. The check for fp() is not 950// necessary on Sparc, but it's harmless. 951bool os::is_first_C_frame(frame* fr) { 952#ifdef IA64 953 // In order to walk native frames on Itanium, we need to access the unwind 954 // table, which is inside ELF. We don't want to parse ELF after fatal error, 955 // so return true for IA64. If we need to support C stack walking on IA64, 956 // this function needs to be moved to CPU specific files, as fp() on IA64 957 // is register stack, which grows towards higher memory address. 958 return true; 959#endif 960 961 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 962 // Check usp first, because if that's bad the other accessors may fault 963 // on some architectures. Ditto ufp second, etc. 964 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 965 // sp on amd can be 32 bit aligned. 966 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 967 968 uintptr_t usp = (uintptr_t)fr->sp(); 969 if ((usp & sp_align_mask) != 0) return true; 970 971 uintptr_t ufp = (uintptr_t)fr->fp(); 972 if ((ufp & fp_align_mask) != 0) return true; 973 974 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 975 if ((old_sp & sp_align_mask) != 0) return true; 976 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 977 978 uintptr_t old_fp = (uintptr_t)fr->link(); 979 if ((old_fp & fp_align_mask) != 0) return true; 980 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 981 982 // stack grows downwards; if old_fp is below current fp or if the stack 983 // frame is too large, either the stack is corrupted or fp is not saved 984 // on stack (i.e. on x86, ebp may be used as general register). The stack 985 // is not walkable beyond current frame. 986 if (old_fp < ufp) return true; 987 if (old_fp - ufp > 64 * K) return true; 988 989 return false; 990} 991 992#ifdef ASSERT 993extern "C" void test_random() { 994 const double m = 2147483647; 995 double mean = 0.0, variance = 0.0, t; 996 long reps = 10000; 997 unsigned long seed = 1; 998 999 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1000 os::init_random(seed); 1001 long num; 1002 for (int k = 0; k < reps; k++) { 1003 num = os::random(); 1004 double u = (double)num / m; 1005 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1006 1007 // calculate mean and variance of the random sequence 1008 mean += u; 1009 variance += (u*u); 1010 } 1011 mean /= reps; 1012 variance /= (reps - 1); 1013 1014 assert(num == 1043618065, "bad seed"); 1015 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1016 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1017 const double eps = 0.0001; 1018 t = fabsd(mean - 0.5018); 1019 assert(t < eps, "bad mean"); 1020 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1021 assert(t < eps, "bad variance"); 1022} 1023#endif 1024 1025 1026// Set up the boot classpath. 1027 1028char* os::format_boot_path(const char* format_string, 1029 const char* home, 1030 int home_len, 1031 char fileSep, 1032 char pathSep) { 1033 assert((fileSep == '/' && pathSep == ':') || 1034 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1035 1036 // Scan the format string to determine the length of the actual 1037 // boot classpath, and handle platform dependencies as well. 1038 int formatted_path_len = 0; 1039 const char* p; 1040 for (p = format_string; *p != 0; ++p) { 1041 if (*p == '%') formatted_path_len += home_len - 1; 1042 ++formatted_path_len; 1043 } 1044 1045 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1); 1046 if (formatted_path == NULL) { 1047 return NULL; 1048 } 1049 1050 // Create boot classpath from format, substituting separator chars and 1051 // java home directory. 1052 char* q = formatted_path; 1053 for (p = format_string; *p != 0; ++p) { 1054 switch (*p) { 1055 case '%': 1056 strcpy(q, home); 1057 q += home_len; 1058 break; 1059 case '/': 1060 *q++ = fileSep; 1061 break; 1062 case ':': 1063 *q++ = pathSep; 1064 break; 1065 default: 1066 *q++ = *p; 1067 } 1068 } 1069 *q = '\0'; 1070 1071 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1072 return formatted_path; 1073} 1074 1075 1076bool os::set_boot_path(char fileSep, char pathSep) { 1077 const char* home = Arguments::get_java_home(); 1078 int home_len = (int)strlen(home); 1079 1080 static const char* meta_index_dir_format = "%/lib/"; 1081 static const char* meta_index_format = "%/lib/meta-index"; 1082 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1083 if (meta_index == NULL) return false; 1084 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1085 if (meta_index_dir == NULL) return false; 1086 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1087 1088 // Any modification to the JAR-file list, for the boot classpath must be 1089 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1090 // path class JARs, are stripped for StackMapTable to reduce download size. 1091 static const char classpath_format[] = 1092 "%/lib/resources.jar:" 1093 "%/lib/rt.jar:" 1094 "%/lib/sunrsasign.jar:" 1095 "%/lib/jsse.jar:" 1096 "%/lib/jce.jar:" 1097 "%/lib/charsets.jar:" 1098#ifdef __APPLE__ 1099 "%/lib/JObjC.jar:" 1100#endif 1101 "%/classes"; 1102 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1103 if (sysclasspath == NULL) return false; 1104 Arguments::set_sysclasspath(sysclasspath); 1105 1106 return true; 1107} 1108 1109/* 1110 * Splits a path, based on its separator, the number of 1111 * elements is returned back in n. 1112 * It is the callers responsibility to: 1113 * a> check the value of n, and n may be 0. 1114 * b> ignore any empty path elements 1115 * c> free up the data. 1116 */ 1117char** os::split_path(const char* path, int* n) { 1118 *n = 0; 1119 if (path == NULL || strlen(path) == 0) { 1120 return NULL; 1121 } 1122 const char psepchar = *os::path_separator(); 1123 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1); 1124 if (inpath == NULL) { 1125 return NULL; 1126 } 1127 strncpy(inpath, path, strlen(path)); 1128 int count = 1; 1129 char* p = strchr(inpath, psepchar); 1130 // Get a count of elements to allocate memory 1131 while (p != NULL) { 1132 count++; 1133 p++; 1134 p = strchr(p, psepchar); 1135 } 1136 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count); 1137 if (opath == NULL) { 1138 return NULL; 1139 } 1140 1141 // do the actual splitting 1142 p = inpath; 1143 for (int i = 0 ; i < count ; i++) { 1144 size_t len = strcspn(p, os::path_separator()); 1145 if (len > JVM_MAXPATHLEN) { 1146 return NULL; 1147 } 1148 // allocate the string and add terminator storage 1149 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1); 1150 if (s == NULL) { 1151 return NULL; 1152 } 1153 strncpy(s, p, len); 1154 s[len] = '\0'; 1155 opath[i] = s; 1156 p += len + 1; 1157 } 1158 FREE_C_HEAP_ARRAY(char, inpath); 1159 *n = count; 1160 return opath; 1161} 1162 1163void os::set_memory_serialize_page(address page) { 1164 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1165 _mem_serialize_page = (volatile int32_t *)page; 1166 // We initialize the serialization page shift count here 1167 // We assume a cache line size of 64 bytes 1168 assert(SerializePageShiftCount == count, 1169 "thread size changed, fix SerializePageShiftCount constant"); 1170 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1171} 1172 1173static volatile intptr_t SerializePageLock = 0; 1174 1175// This method is called from signal handler when SIGSEGV occurs while the current 1176// thread tries to store to the "read-only" memory serialize page during state 1177// transition. 1178void os::block_on_serialize_page_trap() { 1179 if (TraceSafepoint) { 1180 tty->print_cr("Block until the serialize page permission restored"); 1181 } 1182 // When VMThread is holding the SerializePageLock during modifying the 1183 // access permission of the memory serialize page, the following call 1184 // will block until the permission of that page is restored to rw. 1185 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1186 // this case, it's OK as the signal is synchronous and we know precisely when 1187 // it can occur. 1188 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1189 Thread::muxRelease(&SerializePageLock); 1190} 1191 1192// Serialize all thread state variables 1193void os::serialize_thread_states() { 1194 // On some platforms such as Solaris & Linux, the time duration of the page 1195 // permission restoration is observed to be much longer than expected due to 1196 // scheduler starvation problem etc. To avoid the long synchronization 1197 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1198 // the mutator thread if such case is encountered. See bug 6546278 for details. 1199 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1200 os::protect_memory((char *)os::get_memory_serialize_page(), 1201 os::vm_page_size(), MEM_PROT_READ); 1202 os::protect_memory((char *)os::get_memory_serialize_page(), 1203 os::vm_page_size(), MEM_PROT_RW); 1204 Thread::muxRelease(&SerializePageLock); 1205} 1206 1207// Returns true if the current stack pointer is above the stack shadow 1208// pages, false otherwise. 1209 1210bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1211 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1212 address sp = current_stack_pointer(); 1213 // Check if we have StackShadowPages above the yellow zone. This parameter 1214 // is dependent on the depth of the maximum VM call stack possible from 1215 // the handler for stack overflow. 'instanceof' in the stack overflow 1216 // handler or a println uses at least 8k stack of VM and native code 1217 // respectively. 1218 const int framesize_in_bytes = 1219 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1220 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1221 * vm_page_size()) + framesize_in_bytes; 1222 // The very lower end of the stack 1223 address stack_limit = thread->stack_base() - thread->stack_size(); 1224 return (sp > (stack_limit + reserved_area)); 1225} 1226 1227size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1228 uint min_pages) 1229{ 1230 assert(min_pages > 0, "sanity"); 1231 if (UseLargePages) { 1232 const size_t max_page_size = region_max_size / min_pages; 1233 1234 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1235 const size_t sz = _page_sizes[i]; 1236 const size_t mask = sz - 1; 1237 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1238 // The largest page size with no fragmentation. 1239 return sz; 1240 } 1241 1242 if (sz <= max_page_size) { 1243 // The largest page size that satisfies the min_pages requirement. 1244 return sz; 1245 } 1246 } 1247 } 1248 1249 return vm_page_size(); 1250} 1251 1252#ifndef PRODUCT 1253void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1254{ 1255 if (TracePageSizes) { 1256 tty->print("%s: ", str); 1257 for (int i = 0; i < count; ++i) { 1258 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1259 } 1260 tty->cr(); 1261 } 1262} 1263 1264void os::trace_page_sizes(const char* str, const size_t region_min_size, 1265 const size_t region_max_size, const size_t page_size, 1266 const char* base, const size_t size) 1267{ 1268 if (TracePageSizes) { 1269 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1270 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1271 " size=" SIZE_FORMAT, 1272 str, region_min_size, region_max_size, 1273 page_size, base, size); 1274 } 1275} 1276#endif // #ifndef PRODUCT 1277 1278// This is the working definition of a server class machine: 1279// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1280// because the graphics memory (?) sometimes masks physical memory. 1281// If you want to change the definition of a server class machine 1282// on some OS or platform, e.g., >=4GB on Windohs platforms, 1283// then you'll have to parameterize this method based on that state, 1284// as was done for logical processors here, or replicate and 1285// specialize this method for each platform. (Or fix os to have 1286// some inheritance structure and use subclassing. Sigh.) 1287// If you want some platform to always or never behave as a server 1288// class machine, change the setting of AlwaysActAsServerClassMachine 1289// and NeverActAsServerClassMachine in globals*.hpp. 1290bool os::is_server_class_machine() { 1291 // First check for the early returns 1292 if (NeverActAsServerClassMachine) { 1293 return false; 1294 } 1295 if (AlwaysActAsServerClassMachine) { 1296 return true; 1297 } 1298 // Then actually look at the machine 1299 bool result = false; 1300 const unsigned int server_processors = 2; 1301 const julong server_memory = 2UL * G; 1302 // We seem not to get our full complement of memory. 1303 // We allow some part (1/8?) of the memory to be "missing", 1304 // based on the sizes of DIMMs, and maybe graphics cards. 1305 const julong missing_memory = 256UL * M; 1306 1307 /* Is this a server class machine? */ 1308 if ((os::active_processor_count() >= (int)server_processors) && 1309 (os::physical_memory() >= (server_memory - missing_memory))) { 1310 const unsigned int logical_processors = 1311 VM_Version::logical_processors_per_package(); 1312 if (logical_processors > 1) { 1313 const unsigned int physical_packages = 1314 os::active_processor_count() / logical_processors; 1315 if (physical_packages > server_processors) { 1316 result = true; 1317 } 1318 } else { 1319 result = true; 1320 } 1321 } 1322 return result; 1323} 1324 1325// Read file line by line, if line is longer than bsize, 1326// skip rest of line. 1327int os::get_line_chars(int fd, char* buf, const size_t bsize){ 1328 size_t sz, i = 0; 1329 1330 // read until EOF, EOL or buf is full 1331 while ((sz = (int) read(fd, &buf[i], 1)) == 1 && i < (bsize-2) && buf[i] != '\n') { 1332 ++i; 1333 } 1334 1335 if (buf[i] == '\n') { 1336 // EOL reached so ignore EOL character and return 1337 1338 buf[i] = 0; 1339 return (int) i; 1340 } 1341 1342 buf[i+1] = 0; 1343 1344 if (sz != 1) { 1345 // EOF reached. if we read chars before EOF return them and 1346 // return EOF on next call otherwise return EOF 1347 1348 return (i == 0) ? -1 : (int) i; 1349 } 1350 1351 // line is longer than size of buf, skip to EOL 1352 char ch; 1353 while (read(fd, &ch, 1) == 1 && ch != '\n') { 1354 // Do nothing 1355 } 1356 1357 // return initial part of line that fits in buf. 1358 // If we reached EOF, it will be returned on next call. 1359 1360 return (int) i; 1361} 1362