os.cpp revision 4802:f2110083203d
155714Skris/* 255714Skris * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 355714Skris * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 455714Skris * 555714Skris * This code is free software; you can redistribute it and/or modify it 655714Skris * under the terms of the GNU General Public License version 2 only, as 755714Skris * published by the Free Software Foundation. 855714Skris * 955714Skris * This code is distributed in the hope that it will be useful, but WITHOUT 1055714Skris * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1155714Skris * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1255714Skris * version 2 for more details (a copy is included in the LICENSE file that 1355714Skris * accompanied this code). 1455714Skris * 1555714Skris * You should have received a copy of the GNU General Public License version 1655714Skris * 2 along with this work; if not, write to the Free Software Foundation, 1755714Skris * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 1855714Skris * 1955714Skris * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2055714Skris * or visit www.oracle.com if you need additional information or have any 2155714Skris * questions. 2255714Skris * 2355714Skris */ 2455714Skris 2555714Skris#include "precompiled.hpp" 2655714Skris#include "classfile/classLoader.hpp" 2755714Skris#include "classfile/javaClasses.hpp" 2855714Skris#include "classfile/systemDictionary.hpp" 2955714Skris#include "classfile/vmSymbols.hpp" 3055714Skris#include "code/icBuffer.hpp" 3155714Skris#include "code/vtableStubs.hpp" 3255714Skris#include "gc_implementation/shared/vmGCOperations.hpp" 3355714Skris#include "interpreter/interpreter.hpp" 3455714Skris#include "memory/allocation.inline.hpp" 3555714Skris#include "oops/oop.inline.hpp" 3655714Skris#include "prims/jvm.h" 3755714Skris#include "prims/jvm_misc.hpp" 3855714Skris#include "prims/privilegedStack.hpp" 3955714Skris#include "runtime/arguments.hpp" 4055714Skris#include "runtime/frame.inline.hpp" 4155714Skris#include "runtime/interfaceSupport.hpp" 4255714Skris#include "runtime/java.hpp" 4355714Skris#include "runtime/javaCalls.hpp" 4455714Skris#include "runtime/mutexLocker.hpp" 4555714Skris#include "runtime/os.hpp" 4655714Skris#include "runtime/stubRoutines.hpp" 4755714Skris#include "runtime/thread.inline.hpp" 4855714Skris#include "services/attachListener.hpp" 4955714Skris#include "services/memTracker.hpp" 5055714Skris#include "services/threadService.hpp" 5155714Skris#include "utilities/defaultStream.hpp" 5255714Skris#include "utilities/events.hpp" 5355714Skris#ifdef TARGET_OS_FAMILY_linux 5455714Skris# include "os_linux.inline.hpp" 5555714Skris#endif 5655714Skris#ifdef TARGET_OS_FAMILY_solaris 5755714Skris# include "os_solaris.inline.hpp" 5855714Skris#endif 59127128Snectar#ifdef TARGET_OS_FAMILY_windows 60246772Sjkim# include "os_windows.inline.hpp" 61160814Ssimon#endif 62246772Sjkim#ifdef TARGET_OS_FAMILY_bsd 63127128Snectar# include "os_bsd.inline.hpp" 6455714Skris#endif 6555714Skris 6655714Skris# include <signal.h> 6755714Skris 6855714SkrisOSThread* os::_starting_thread = NULL; 69109998Smarkmaddress os::_polling_page = NULL; 70109998Smarkmvolatile int32_t* os::_mem_serialize_page = NULL; 71109998Smarkmuintptr_t os::_serialize_page_mask = 0; 72127128Snectarlong os::_rand_seed = 1; 73109998Smarkmint os::_processor_count = 0; 74109998Smarkmsize_t os::_page_sizes[os::page_sizes_max]; 7559191Skris 7659191Skris#ifndef PRODUCT 7759191Skrisjulong os::num_mallocs = 0; // # of calls to malloc/realloc 7859191Skrisjulong os::alloc_bytes = 0; // # of bytes allocated 7959191Skrisjulong os::num_frees = 0; // # of calls to free 80238405Sjkimjulong os::free_bytes = 0; // # of bytes freed 8159191Skris#endif 82279264Sdelphij 8359191Skrisstatic juint cur_malloc_words = 0; // current size for MallocMaxTestWords 8459191Skris 85194206Ssimonvoid os_init_globals() { 86194206Ssimon // Called from init_globals(). 87194206Ssimon // See Threads::create_vm() in thread.cpp, and init.cpp. 88194206Ssimon os::init_globals(); 89194206Ssimon} 90194206Ssimon 91194206Ssimon// Fill in buffer with current local time as an ISO-8601 string. 9255714Skris// E.g., yyyy-mm-ddThh:mm:ss-zzzz. 9355714Skris// Returns buffer, or NULL if it failed. 9455714Skris// This would mostly be a call to 9555714Skris// strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 96194206Ssimon// except that on Windows the %z behaves badly, so we do it ourselves. 97194206Ssimon// Also, people wanted milliseconds on there, 98194206Ssimon// and strftime doesn't do milliseconds. 99194206Ssimonchar* os::iso8601_time(char* buffer, size_t buffer_length) { 100194206Ssimon // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 101194206Ssimon // 1 2 102194206Ssimon // 12345678901234567890123456789 103194206Ssimon static const char* iso8601_format = 10459191Skris "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; 10555714Skris static const size_t needed_buffer = 29; 10672613Skris 10772613Skris // Sanity check the arguments 10872613Skris if (buffer == NULL) { 10955714Skris assert(false, "NULL buffer"); 11055714Skris return NULL; 11159191Skris } 11259191Skris if (buffer_length < needed_buffer) { 11359191Skris assert(false, "buffer_length too small"); 11455714Skris return NULL; 115238405Sjkim } 11655714Skris // Get the current time 117238405Sjkim jlong milliseconds_since_19700101 = javaTimeMillis(); 11855714Skris const int milliseconds_per_microsecond = 1000; 11955714Skris const time_t seconds_since_19700101 = 12055714Skris milliseconds_since_19700101 / milliseconds_per_microsecond; 12155714Skris const int milliseconds_after_second = 12255714Skris milliseconds_since_19700101 % milliseconds_per_microsecond; 123238405Sjkim // Convert the time value to a tm and timezone variable 124205128Ssimon struct tm time_struct; 125205128Ssimon if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 126205128Ssimon assert(false, "Failed localtime_pd"); 127205128Ssimon return NULL; 128205128Ssimon } 129205128Ssimon#if defined(_ALLBSD_SOURCE) 130205128Ssimon const time_t zone = (time_t) time_struct.tm_gmtoff; 131205128Ssimon#else 132194206Ssimon const time_t zone = timezone; 133160814Ssimon#endif 134238405Sjkim 13559191Skris // If daylight savings time is in effect, 13655714Skris // we are 1 hour East of our time zone 137194206Ssimon const time_t seconds_per_minute = 60; 138194206Ssimon const time_t minutes_per_hour = 60; 139194206Ssimon const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 14055714Skris time_t UTC_to_local = zone; 141194206Ssimon if (time_struct.tm_isdst > 0) { 14255714Skris UTC_to_local = UTC_to_local - seconds_per_hour; 143238405Sjkim } 144238405Sjkim // Compute the time zone offset. 145127128Snectar // localtime_pd() sets timezone to the difference (in seconds) 146127128Snectar // between UTC and and local time. 147127128Snectar // ISO 8601 says we need the difference between local time and UTC, 148127128Snectar // we change the sign of the localtime_pd() result. 149127128Snectar const time_t local_to_UTC = -(UTC_to_local); 150238405Sjkim // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 151127128Snectar char sign_local_to_UTC = '+'; 152238405Sjkim time_t abs_local_to_UTC = local_to_UTC; 153127128Snectar if (local_to_UTC < 0) { 154127128Snectar sign_local_to_UTC = '-'; 15555714Skris abs_local_to_UTC = -(abs_local_to_UTC); 15655714Skris } 15759191Skris // Convert time zone offset seconds to hours and minutes. 15859191Skris const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 15959191Skris const time_t zone_min = 16059191Skris ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 16155714Skris 16255714Skris // Print an ISO 8601 date and time stamp into the buffer 163194206Ssimon const int year = 1900 + time_struct.tm_year; 164194206Ssimon const int month = 1 + time_struct.tm_mon; 165194206Ssimon const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, 16655714Skris year, 167160814Ssimon month, 168194206Ssimon time_struct.tm_mday, 16955714Skris time_struct.tm_hour, 17059191Skris time_struct.tm_min, 17159191Skris time_struct.tm_sec, 17259191Skris milliseconds_after_second, 17372613Skris sign_local_to_UTC, 17459191Skris zone_hours, 17555714Skris zone_min); 17655714Skris if (printed == 0) { 177109998Smarkm assert(false, "Failed jio_printf"); 17855714Skris return NULL; 17955714Skris } 18055714Skris return buffer; 18155714Skris} 18255714Skris 18355714SkrisOSReturn os::set_priority(Thread* thread, ThreadPriority p) { 18455714Skris#ifdef ASSERT 18568651Skris if (!(!thread->is_Java_thread() || 18659191Skris Thread::current() == thread || 18755714Skris Threads_lock->owned_by_self() 188238405Sjkim || thread->is_Compiler_thread() 189127128Snectar )) { 19059191Skris assert(false, "possibility of dangling Thread pointer"); 191127128Snectar } 192127128Snectar#endif 193205128Ssimon 194205128Ssimon if (p >= MinPriority && p <= MaxPriority) { 195127128Snectar int priority = java_to_os_priority[p]; 196127128Snectar return set_native_priority(thread, priority); 197127128Snectar } else { 198127128Snectar assert(false, "Should not happen"); 199127128Snectar return OS_ERR; 200127128Snectar } 201127128Snectar} 202127128Snectar 203127128Snectar// The mapping from OS priority back to Java priority may be inexact because 204238405Sjkim// Java priorities can map M:1 with native priorities. If you want the definite 205127128Snectar// Java priority then use JavaThread::java_priority() 206238405SjkimOSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 207142425Snectar int p; 208238405Sjkim int os_prio; 209238405Sjkim OSReturn ret = get_native_priority(thread, &os_prio); 210238405Sjkim if (ret != OS_OK) return ret; 21168651Skris 21268651Skris if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 213238405Sjkim for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 21468651Skris } else { 21568651Skris // niceness values are in reverse order 216142425Snectar for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 21759191Skris } 218194206Ssimon priority = (ThreadPriority)p; 219194206Ssimon return OS_OK; 220194206Ssimon} 221194206Ssimon 222194206Ssimon 223194206Ssimon// --------------------- sun.misc.Signal (optional) --------------------- 224194206Ssimon 225194206Ssimon 226194206Ssimon// SIGBREAK is sent by the keyboard to query the VM state 227194206Ssimon#ifndef SIGBREAK 228194206Ssimon#define SIGBREAK SIGQUIT 229194206Ssimon#endif 230194206Ssimon 231194206Ssimon// sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 232194206Ssimon 233194206Ssimon 234194206Ssimonstatic void signal_thread_entry(JavaThread* thread, TRAPS) { 235194206Ssimon os::set_priority(thread, NearMaxPriority); 236194206Ssimon while (true) { 237194206Ssimon int sig; 238194206Ssimon { 239194206Ssimon // FIXME : Currently we have not decieded what should be the status 24068651Skris // for this java thread blocked here. Once we decide about 241194206Ssimon // that we should fix this. 242194206Ssimon sig = os::signal_wait(); 243194206Ssimon } 24468651Skris if (sig == os::sigexitnum_pd()) { 245194206Ssimon // Terminate the signal thread 24668651Skris return; 24759191Skris } 24859191Skris 24955714Skris switch (sig) { 25059191Skris case SIGBREAK: { 25155714Skris // Check if the signal is a trigger to start the Attach Listener - in that 25255714Skris // case don't print stack traces. 25355714Skris if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 25455714Skris continue; 25555714Skris } 25659191Skris // Print stack traces 25768651Skris // Any SIGBREAK operations added here should make sure to flush 25855714Skris // the output stream (e.g. tty->flush()) after output. See 4803766. 25955714Skris // Each module also prints an extra carriage return after its output. 26055714Skris VM_PrintThreads op; 26155714Skris VMThread::execute(&op); 26255714Skris VM_PrintJNI jni_op; 26355714Skris VMThread::execute(&jni_op); 26455714Skris VM_FindDeadlocks op1(tty); 26555714Skris VMThread::execute(&op1); 26659191Skris Universe::print_heap_at_SIGBREAK(); 26759191Skris if (PrintClassHistogram) { 26855714Skris VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */); 269109998Smarkm VMThread::execute(&op1); 27055714Skris } 27168651Skris if (JvmtiExport::should_post_data_dump()) { 27255714Skris JvmtiExport::post_data_dump(); 27355714Skris } 27476866Skris break; 27555714Skris } 27676866Skris default: { 277215697Ssimon // Dispatch the signal to java 278127128Snectar HandleMark hm(THREAD); 279127128Snectar Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 28055714Skris KlassHandle klass (THREAD, k); 28176866Skris if (klass.not_null()) { 28276866Skris JavaValue result(T_VOID); 283127128Snectar JavaCallArguments args; 28455714Skris args.push_int(sig); 285127128Snectar JavaCalls::call_static( 286109998Smarkm &result, 28755714Skris klass, 28855714Skris vmSymbols::dispatch_name(), 28955714Skris vmSymbols::int_void_signature(), 29076866Skris &args, 29176866Skris THREAD 29279998Skris ); 29379998Skris } 29479998Skris if (HAS_PENDING_EXCEPTION) { 29579998Skris // tty is initialized early so we don't expect it to be null, but 29679998Skris // if it is we can't risk doing an initialization that might 29779998Skris // trigger additional out-of-memory conditions 298127128Snectar if (tty != NULL) { 29976866Skris char klass_name[256]; 300127128Snectar char tmp_sig_name[16]; 301109998Smarkm const char* sig_name = "UNKNOWN"; 302127128Snectar InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 30355714Skris name()->as_klass_external_name(klass_name, 256); 304127128Snectar if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 30576866Skris sig_name = tmp_sig_name; 30679998Skris warning("Exception %s occurred dispatching signal %s to handler" 30776866Skris "- the VM may need to be forcibly terminated", 30855714Skris klass_name, sig_name ); 309127128Snectar } 310127128Snectar CLEAR_PENDING_EXCEPTION; 311127128Snectar } 312127128Snectar } 313127128Snectar } 314127128Snectar } 315127128Snectar} 316127128Snectar 317127128Snectar 318238405Sjkimvoid os::signal_init() { 319127128Snectar if (!ReduceSignalUsage) { 320127128Snectar // Setup JavaThread for processing signals 321127128Snectar EXCEPTION_MARK; 322127128Snectar Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 323127128Snectar instanceKlassHandle klass (THREAD, k); 324127128Snectar instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 325127128Snectar 326127128Snectar const char thread_name[] = "Signal Dispatcher"; 327127128Snectar Handle string = java_lang_String::create_from_str(thread_name, CHECK); 328127128Snectar 32955714Skris // Initialize thread_oop to put it into the system threadGroup 330 Handle thread_group (THREAD, Universe::system_thread_group()); 331 JavaValue result(T_VOID); 332 JavaCalls::call_special(&result, thread_oop, 333 klass, 334 vmSymbols::object_initializer_name(), 335 vmSymbols::threadgroup_string_void_signature(), 336 thread_group, 337 string, 338 CHECK); 339 340 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 341 JavaCalls::call_special(&result, 342 thread_group, 343 group, 344 vmSymbols::add_method_name(), 345 vmSymbols::thread_void_signature(), 346 thread_oop, // ARG 1 347 CHECK); 348 349 os::signal_init_pd(); 350 351 { MutexLocker mu(Threads_lock); 352 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 353 354 // At this point it may be possible that no osthread was created for the 355 // JavaThread due to lack of memory. We would have to throw an exception 356 // in that case. However, since this must work and we do not allow 357 // exceptions anyway, check and abort if this fails. 358 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 359 vm_exit_during_initialization("java.lang.OutOfMemoryError", 360 "unable to create new native thread"); 361 } 362 363 java_lang_Thread::set_thread(thread_oop(), signal_thread); 364 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 365 java_lang_Thread::set_daemon(thread_oop()); 366 367 signal_thread->set_threadObj(thread_oop()); 368 Threads::add(signal_thread); 369 Thread::start(signal_thread); 370 } 371 // Handle ^BREAK 372 os::signal(SIGBREAK, os::user_handler()); 373 } 374} 375 376 377void os::terminate_signal_thread() { 378 if (!ReduceSignalUsage) 379 signal_notify(sigexitnum_pd()); 380} 381 382 383// --------------------- loading libraries --------------------- 384 385typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 386extern struct JavaVM_ main_vm; 387 388static void* _native_java_library = NULL; 389 390void* os::native_java_library() { 391 if (_native_java_library == NULL) { 392 char buffer[JVM_MAXPATHLEN]; 393 char ebuf[1024]; 394 395 // Try to load verify dll first. In 1.3 java dll depends on it and is not 396 // always able to find it when the loading executable is outside the JDK. 397 // In order to keep working with 1.2 we ignore any loading errors. 398 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 399 "verify")) { 400 dll_load(buffer, ebuf, sizeof(ebuf)); 401 } 402 403 // Load java dll 404 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 405 "java")) { 406 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 407 } 408 if (_native_java_library == NULL) { 409 vm_exit_during_initialization("Unable to load native library", ebuf); 410 } 411 412#if defined(__OpenBSD__) 413 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 414 // ignore errors 415 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 416 "net")) { 417 dll_load(buffer, ebuf, sizeof(ebuf)); 418 } 419#endif 420 } 421 static jboolean onLoaded = JNI_FALSE; 422 if (onLoaded) { 423 // We may have to wait to fire OnLoad until TLS is initialized. 424 if (ThreadLocalStorage::is_initialized()) { 425 // The JNI_OnLoad handling is normally done by method load in 426 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 427 // explicitly so we have to check for JNI_OnLoad as well 428 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 429 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 430 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 431 if (JNI_OnLoad != NULL) { 432 JavaThread* thread = JavaThread::current(); 433 ThreadToNativeFromVM ttn(thread); 434 HandleMark hm(thread); 435 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 436 onLoaded = JNI_TRUE; 437 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 438 vm_exit_during_initialization("Unsupported JNI version"); 439 } 440 } 441 } 442 } 443 return _native_java_library; 444} 445 446// --------------------- heap allocation utilities --------------------- 447 448char *os::strdup(const char *str, MEMFLAGS flags) { 449 size_t size = strlen(str); 450 char *dup_str = (char *)malloc(size + 1, flags); 451 if (dup_str == NULL) return NULL; 452 strcpy(dup_str, str); 453 return dup_str; 454} 455 456 457 458#ifdef ASSERT 459#define space_before (MallocCushion + sizeof(double)) 460#define space_after MallocCushion 461#define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) 462#define size_addr_from_obj(p) ((size_t*)p - 1) 463// MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly 464// NB: cannot be debug variable, because these aren't set from the command line until 465// *after* the first few allocs already happened 466#define MallocCushion 16 467#else 468#define space_before 0 469#define space_after 0 470#define size_addr_from_base(p) should not use w/o ASSERT 471#define size_addr_from_obj(p) should not use w/o ASSERT 472#define MallocCushion 0 473#endif 474#define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 475 476#ifdef ASSERT 477inline size_t get_size(void* obj) { 478 size_t size = *size_addr_from_obj(obj); 479 if (size < 0) { 480 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten (" 481 SIZE_FORMAT ")", obj, size)); 482 } 483 return size; 484} 485 486u_char* find_cushion_backwards(u_char* start) { 487 u_char* p = start; 488 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || 489 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; 490 // ok, we have four consecutive marker bytes; find start 491 u_char* q = p - 4; 492 while (*q == badResourceValue) q--; 493 return q + 1; 494} 495 496u_char* find_cushion_forwards(u_char* start) { 497 u_char* p = start; 498 while (p[0] != badResourceValue || p[1] != badResourceValue || 499 p[2] != badResourceValue || p[3] != badResourceValue) p++; 500 // ok, we have four consecutive marker bytes; find end of cushion 501 u_char* q = p + 4; 502 while (*q == badResourceValue) q++; 503 return q - MallocCushion; 504} 505 506void print_neighbor_blocks(void* ptr) { 507 // find block allocated before ptr (not entirely crash-proof) 508 if (MallocCushion < 4) { 509 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); 510 return; 511 } 512 u_char* start_of_this_block = (u_char*)ptr - space_before; 513 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; 514 // look for cushion in front of prev. block 515 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); 516 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); 517 u_char* obj = start_of_prev_block + space_before; 518 if (size <= 0 ) { 519 // start is bad; mayhave been confused by OS data inbetween objects 520 // search one more backwards 521 start_of_prev_block = find_cushion_backwards(start_of_prev_block); 522 size = *size_addr_from_base(start_of_prev_block); 523 obj = start_of_prev_block + space_before; 524 } 525 526 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { 527 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 528 } else { 529 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size); 530 } 531 532 // now find successor block 533 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; 534 start_of_next_block = find_cushion_forwards(start_of_next_block); 535 u_char* next_obj = start_of_next_block + space_before; 536 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); 537 if (start_of_next_block[0] == badResourceValue && 538 start_of_next_block[1] == badResourceValue && 539 start_of_next_block[2] == badResourceValue && 540 start_of_next_block[3] == badResourceValue) { 541 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 542 } else { 543 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size); 544 } 545} 546 547 548void report_heap_error(void* memblock, void* bad, const char* where) { 549 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 550 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock); 551 print_neighbor_blocks(memblock); 552 fatal("memory stomping error"); 553} 554 555void verify_block(void* memblock) { 556 size_t size = get_size(memblock); 557 if (MallocCushion) { 558 u_char* ptr = (u_char*)memblock - space_before; 559 for (int i = 0; i < MallocCushion; i++) { 560 if (ptr[i] != badResourceValue) { 561 report_heap_error(memblock, ptr+i, "in front of"); 562 } 563 } 564 u_char* end = (u_char*)memblock + size + space_after; 565 for (int j = -MallocCushion; j < 0; j++) { 566 if (end[j] != badResourceValue) { 567 report_heap_error(memblock, end+j, "after"); 568 } 569 } 570 } 571} 572#endif 573 574// 575// This function supports testing of the malloc out of memory 576// condition without really running the system out of memory. 577// 578static u_char* testMalloc(size_t alloc_size) { 579 assert(MallocMaxTestWords > 0, "sanity check"); 580 581 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 582 return NULL; 583 } 584 585 u_char* ptr = (u_char*)::malloc(alloc_size); 586 587 if (ptr != NULL) { 588 Atomic::add(((jint) (alloc_size / BytesPerWord)), 589 (volatile jint *) &cur_malloc_words); 590 } 591 return ptr; 592} 593 594void* os::malloc(size_t size, MEMFLAGS memflags, address caller) { 595 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 596 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 597 598 if (size == 0) { 599 // return a valid pointer if size is zero 600 // if NULL is returned the calling functions assume out of memory. 601 size = 1; 602 } 603 604 const size_t alloc_size = size + space_before + space_after; 605 606 if (size > alloc_size) { // Check for rollover. 607 return NULL; 608 } 609 610 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 611 612 u_char* ptr; 613 614 if (MallocMaxTestWords > 0) { 615 ptr = testMalloc(alloc_size); 616 } else { 617 ptr = (u_char*)::malloc(alloc_size); 618 } 619 620#ifdef ASSERT 621 if (ptr == NULL) return NULL; 622 if (MallocCushion) { 623 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; 624 u_char* end = ptr + space_before + size; 625 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; 626 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; 627 } 628 // put size just before data 629 *size_addr_from_base(ptr) = size; 630#endif 631 u_char* memblock = ptr + space_before; 632 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 633 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 634 breakpoint(); 635 } 636 debug_only(if (paranoid) verify_block(memblock)); 637 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock); 638 639 // we do not track MallocCushion memory 640 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller); 641 642 return memblock; 643} 644 645 646void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) { 647#ifndef ASSERT 648 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 649 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 650 void* ptr = ::realloc(memblock, size); 651 if (ptr != NULL) { 652 MemTracker::record_realloc((address)memblock, (address)ptr, size, memflags, 653 caller == 0 ? CALLER_PC : caller); 654 } 655 return ptr; 656#else 657 if (memblock == NULL) { 658 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller)); 659 } 660 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 661 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 662 breakpoint(); 663 } 664 verify_block(memblock); 665 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 666 if (size == 0) return NULL; 667 // always move the block 668 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller); 669 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 670 // Copy to new memory if malloc didn't fail 671 if ( ptr != NULL ) { 672 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); 673 if (paranoid) verify_block(ptr); 674 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 675 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 676 breakpoint(); 677 } 678 free(memblock); 679 } 680 return ptr; 681#endif 682} 683 684 685void os::free(void *memblock, MEMFLAGS memflags) { 686 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 687#ifdef ASSERT 688 if (memblock == NULL) return; 689 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 690 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 691 breakpoint(); 692 } 693 verify_block(memblock); 694 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 695 // Added by detlefs. 696 if (MallocCushion) { 697 u_char* ptr = (u_char*)memblock - space_before; 698 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { 699 guarantee(*p == badResourceValue, 700 "Thing freed should be malloc result."); 701 *p = (u_char)freeBlockPad; 702 } 703 size_t size = get_size(memblock); 704 inc_stat_counter(&free_bytes, size); 705 u_char* end = ptr + space_before + size; 706 for (u_char* q = end; q < end + MallocCushion; q++) { 707 guarantee(*q == badResourceValue, 708 "Thing freed should be malloc result."); 709 *q = (u_char)freeBlockPad; 710 } 711 if (PrintMalloc && tty != NULL) 712 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock); 713 } else if (PrintMalloc && tty != NULL) { 714 // tty->print_cr("os::free %p", memblock); 715 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock); 716 } 717#endif 718 MemTracker::record_free((address)memblock, memflags); 719 720 ::free((char*)memblock - space_before); 721} 722 723void os::init_random(long initval) { 724 _rand_seed = initval; 725} 726 727 728long os::random() { 729 /* standard, well-known linear congruential random generator with 730 * next_rand = (16807*seed) mod (2**31-1) 731 * see 732 * (1) "Random Number Generators: Good Ones Are Hard to Find", 733 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 734 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 735 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 736 */ 737 const long a = 16807; 738 const unsigned long m = 2147483647; 739 const long q = m / a; assert(q == 127773, "weird math"); 740 const long r = m % a; assert(r == 2836, "weird math"); 741 742 // compute az=2^31p+q 743 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 744 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 745 lo += (hi & 0x7FFF) << 16; 746 747 // if q overflowed, ignore the overflow and increment q 748 if (lo > m) { 749 lo &= m; 750 ++lo; 751 } 752 lo += hi >> 15; 753 754 // if (p+q) overflowed, ignore the overflow and increment (p+q) 755 if (lo > m) { 756 lo &= m; 757 ++lo; 758 } 759 return (_rand_seed = lo); 760} 761 762// The INITIALIZED state is distinguished from the SUSPENDED state because the 763// conditions in which a thread is first started are different from those in which 764// a suspension is resumed. These differences make it hard for us to apply the 765// tougher checks when starting threads that we want to do when resuming them. 766// However, when start_thread is called as a result of Thread.start, on a Java 767// thread, the operation is synchronized on the Java Thread object. So there 768// cannot be a race to start the thread and hence for the thread to exit while 769// we are working on it. Non-Java threads that start Java threads either have 770// to do so in a context in which races are impossible, or should do appropriate 771// locking. 772 773void os::start_thread(Thread* thread) { 774 // guard suspend/resume 775 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 776 OSThread* osthread = thread->osthread(); 777 osthread->set_state(RUNNABLE); 778 pd_start_thread(thread); 779} 780 781//--------------------------------------------------------------------------- 782// Helper functions for fatal error handler 783 784void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 785 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 786 787 int cols = 0; 788 int cols_per_line = 0; 789 switch (unitsize) { 790 case 1: cols_per_line = 16; break; 791 case 2: cols_per_line = 8; break; 792 case 4: cols_per_line = 4; break; 793 case 8: cols_per_line = 2; break; 794 default: return; 795 } 796 797 address p = start; 798 st->print(PTR_FORMAT ": ", start); 799 while (p < end) { 800 switch (unitsize) { 801 case 1: st->print("%02x", *(u1*)p); break; 802 case 2: st->print("%04x", *(u2*)p); break; 803 case 4: st->print("%08x", *(u4*)p); break; 804 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 805 } 806 p += unitsize; 807 cols++; 808 if (cols >= cols_per_line && p < end) { 809 cols = 0; 810 st->cr(); 811 st->print(PTR_FORMAT ": ", p); 812 } else { 813 st->print(" "); 814 } 815 } 816 st->cr(); 817} 818 819void os::print_environment_variables(outputStream* st, const char** env_list, 820 char* buffer, int len) { 821 if (env_list) { 822 st->print_cr("Environment Variables:"); 823 824 for (int i = 0; env_list[i] != NULL; i++) { 825 if (getenv(env_list[i], buffer, len)) { 826 st->print(env_list[i]); 827 st->print("="); 828 st->print_cr(buffer); 829 } 830 } 831 } 832} 833 834void os::print_cpu_info(outputStream* st) { 835 // cpu 836 st->print("CPU:"); 837 st->print("total %d", os::processor_count()); 838 // It's not safe to query number of active processors after crash 839 // st->print("(active %d)", os::active_processor_count()); 840 st->print(" %s", VM_Version::cpu_features()); 841 st->cr(); 842 pd_print_cpu_info(st); 843} 844 845void os::print_date_and_time(outputStream *st) { 846 time_t tloc; 847 (void)time(&tloc); 848 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 849 850 double t = os::elapsedTime(); 851 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 852 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 853 // before printf. We lost some precision, but who cares? 854 st->print_cr("elapsed time: %d seconds", (int)t); 855} 856 857// moved from debug.cpp (used to be find()) but still called from there 858// The verbose parameter is only set by the debug code in one case 859void os::print_location(outputStream* st, intptr_t x, bool verbose) { 860 address addr = (address)x; 861 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 862 if (b != NULL) { 863 if (b->is_buffer_blob()) { 864 // the interpreter is generated into a buffer blob 865 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 866 if (i != NULL) { 867 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 868 i->print_on(st); 869 return; 870 } 871 if (Interpreter::contains(addr)) { 872 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 873 " (not bytecode specific)", addr); 874 return; 875 } 876 // 877 if (AdapterHandlerLibrary::contains(b)) { 878 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 879 AdapterHandlerLibrary::print_handler_on(st, b); 880 } 881 // the stubroutines are generated into a buffer blob 882 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 883 if (d != NULL) { 884 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 885 d->print_on(st); 886 st->cr(); 887 return; 888 } 889 if (StubRoutines::contains(addr)) { 890 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 891 "stub routine", addr); 892 return; 893 } 894 // the InlineCacheBuffer is using stubs generated into a buffer blob 895 if (InlineCacheBuffer::contains(addr)) { 896 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 897 return; 898 } 899 VtableStub* v = VtableStubs::stub_containing(addr); 900 if (v != NULL) { 901 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 902 v->print_on(st); 903 st->cr(); 904 return; 905 } 906 } 907 nmethod* nm = b->as_nmethod_or_null(); 908 if (nm != NULL) { 909 ResourceMark rm; 910 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 911 addr, (int)(addr - nm->entry_point()), nm); 912 if (verbose) { 913 st->print(" for "); 914 nm->method()->print_value_on(st); 915 } 916 st->cr(); 917 nm->print_nmethod(verbose); 918 return; 919 } 920 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 921 b->print_on(st); 922 return; 923 } 924 925 if (Universe::heap()->is_in(addr)) { 926 HeapWord* p = Universe::heap()->block_start(addr); 927 bool print = false; 928 // If we couldn't find it it just may mean that heap wasn't parseable 929 // See if we were just given an oop directly 930 if (p != NULL && Universe::heap()->block_is_obj(p)) { 931 print = true; 932 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 933 p = (HeapWord*) addr; 934 print = true; 935 } 936 if (print) { 937 if (p == (HeapWord*) addr) { 938 st->print_cr(INTPTR_FORMAT " is an oop", addr); 939 } else { 940 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 941 } 942 oop(p)->print_on(st); 943 return; 944 } 945 } else { 946 if (Universe::heap()->is_in_reserved(addr)) { 947 st->print_cr(INTPTR_FORMAT " is an unallocated location " 948 "in the heap", addr); 949 return; 950 } 951 } 952 if (JNIHandles::is_global_handle((jobject) addr)) { 953 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 954 return; 955 } 956 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 957 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 958 return; 959 } 960#ifndef PRODUCT 961 // we don't keep the block list in product mode 962 if (JNIHandleBlock::any_contains((jobject) addr)) { 963 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 964 return; 965 } 966#endif 967 968 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 969 // Check for privilege stack 970 if (thread->privileged_stack_top() != NULL && 971 thread->privileged_stack_top()->contains(addr)) { 972 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 973 "for thread: " INTPTR_FORMAT, addr, thread); 974 if (verbose) thread->print_on(st); 975 return; 976 } 977 // If the addr is a java thread print information about that. 978 if (addr == (address)thread) { 979 if (verbose) { 980 thread->print_on(st); 981 } else { 982 st->print_cr(INTPTR_FORMAT " is a thread", addr); 983 } 984 return; 985 } 986 // If the addr is in the stack region for this thread then report that 987 // and print thread info 988 if (thread->stack_base() >= addr && 989 addr > (thread->stack_base() - thread->stack_size())) { 990 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 991 INTPTR_FORMAT, addr, thread); 992 if (verbose) thread->print_on(st); 993 return; 994 } 995 996 } 997 998#ifndef PRODUCT 999 // Check if in metaspace. 1000 if (ClassLoaderDataGraph::contains((address)addr)) { 1001 // Use addr->print() from the debugger instead (not here) 1002 st->print_cr(INTPTR_FORMAT 1003 " is pointing into metadata", addr); 1004 return; 1005 } 1006#endif 1007 1008 // Try an OS specific find 1009 if (os::find(addr, st)) { 1010 return; 1011 } 1012 1013 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1014} 1015 1016// Looks like all platforms except IA64 can use the same function to check 1017// if C stack is walkable beyond current frame. The check for fp() is not 1018// necessary on Sparc, but it's harmless. 1019bool os::is_first_C_frame(frame* fr) { 1020#if defined(IA64) && !defined(_WIN32) 1021 // On IA64 we have to check if the callers bsp is still valid 1022 // (i.e. within the register stack bounds). 1023 // Notice: this only works for threads created by the VM and only if 1024 // we walk the current stack!!! If we want to be able to walk 1025 // arbitrary other threads, we'll have to somehow store the thread 1026 // object in the frame. 1027 Thread *thread = Thread::current(); 1028 if ((address)fr->fp() <= 1029 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1030 // This check is a little hacky, because on Linux the first C 1031 // frame's ('start_thread') register stack frame starts at 1032 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1033 // ('__pthread_bound_body') register stack frame seems to really 1034 // start at "register_stack_base". 1035 return true; 1036 } else { 1037 return false; 1038 } 1039#elif defined(IA64) && defined(_WIN32) 1040 return true; 1041#else 1042 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1043 // Check usp first, because if that's bad the other accessors may fault 1044 // on some architectures. Ditto ufp second, etc. 1045 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1046 // sp on amd can be 32 bit aligned. 1047 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1048 1049 uintptr_t usp = (uintptr_t)fr->sp(); 1050 if ((usp & sp_align_mask) != 0) return true; 1051 1052 uintptr_t ufp = (uintptr_t)fr->fp(); 1053 if ((ufp & fp_align_mask) != 0) return true; 1054 1055 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1056 if ((old_sp & sp_align_mask) != 0) return true; 1057 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1058 1059 uintptr_t old_fp = (uintptr_t)fr->link(); 1060 if ((old_fp & fp_align_mask) != 0) return true; 1061 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1062 1063 // stack grows downwards; if old_fp is below current fp or if the stack 1064 // frame is too large, either the stack is corrupted or fp is not saved 1065 // on stack (i.e. on x86, ebp may be used as general register). The stack 1066 // is not walkable beyond current frame. 1067 if (old_fp < ufp) return true; 1068 if (old_fp - ufp > 64 * K) return true; 1069 1070 return false; 1071#endif 1072} 1073 1074#ifdef ASSERT 1075extern "C" void test_random() { 1076 const double m = 2147483647; 1077 double mean = 0.0, variance = 0.0, t; 1078 long reps = 10000; 1079 unsigned long seed = 1; 1080 1081 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1082 os::init_random(seed); 1083 long num; 1084 for (int k = 0; k < reps; k++) { 1085 num = os::random(); 1086 double u = (double)num / m; 1087 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1088 1089 // calculate mean and variance of the random sequence 1090 mean += u; 1091 variance += (u*u); 1092 } 1093 mean /= reps; 1094 variance /= (reps - 1); 1095 1096 assert(num == 1043618065, "bad seed"); 1097 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1098 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1099 const double eps = 0.0001; 1100 t = fabsd(mean - 0.5018); 1101 assert(t < eps, "bad mean"); 1102 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1103 assert(t < eps, "bad variance"); 1104} 1105#endif 1106 1107 1108// Set up the boot classpath. 1109 1110char* os::format_boot_path(const char* format_string, 1111 const char* home, 1112 int home_len, 1113 char fileSep, 1114 char pathSep) { 1115 assert((fileSep == '/' && pathSep == ':') || 1116 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); 1117 1118 // Scan the format string to determine the length of the actual 1119 // boot classpath, and handle platform dependencies as well. 1120 int formatted_path_len = 0; 1121 const char* p; 1122 for (p = format_string; *p != 0; ++p) { 1123 if (*p == '%') formatted_path_len += home_len - 1; 1124 ++formatted_path_len; 1125 } 1126 1127 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1128 if (formatted_path == NULL) { 1129 return NULL; 1130 } 1131 1132 // Create boot classpath from format, substituting separator chars and 1133 // java home directory. 1134 char* q = formatted_path; 1135 for (p = format_string; *p != 0; ++p) { 1136 switch (*p) { 1137 case '%': 1138 strcpy(q, home); 1139 q += home_len; 1140 break; 1141 case '/': 1142 *q++ = fileSep; 1143 break; 1144 case ':': 1145 *q++ = pathSep; 1146 break; 1147 default: 1148 *q++ = *p; 1149 } 1150 } 1151 *q = '\0'; 1152 1153 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1154 return formatted_path; 1155} 1156 1157 1158bool os::set_boot_path(char fileSep, char pathSep) { 1159 const char* home = Arguments::get_java_home(); 1160 int home_len = (int)strlen(home); 1161 1162 static const char* meta_index_dir_format = "%/lib/"; 1163 static const char* meta_index_format = "%/lib/meta-index"; 1164 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1165 if (meta_index == NULL) return false; 1166 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1167 if (meta_index_dir == NULL) return false; 1168 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1169 1170 // Any modification to the JAR-file list, for the boot classpath must be 1171 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1172 // path class JARs, are stripped for StackMapTable to reduce download size. 1173 static const char classpath_format[] = 1174 "%/lib/resources.jar:" 1175 "%/lib/rt.jar:" 1176 "%/lib/sunrsasign.jar:" 1177 "%/lib/jsse.jar:" 1178 "%/lib/jce.jar:" 1179 "%/lib/charsets.jar:" 1180 "%/lib/jfr.jar:" 1181#ifdef __APPLE__ 1182 "%/lib/JObjC.jar:" 1183#endif 1184 "%/classes"; 1185 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1186 if (sysclasspath == NULL) return false; 1187 Arguments::set_sysclasspath(sysclasspath); 1188 1189 return true; 1190} 1191 1192/* 1193 * Splits a path, based on its separator, the number of 1194 * elements is returned back in n. 1195 * It is the callers responsibility to: 1196 * a> check the value of n, and n may be 0. 1197 * b> ignore any empty path elements 1198 * c> free up the data. 1199 */ 1200char** os::split_path(const char* path, int* n) { 1201 *n = 0; 1202 if (path == NULL || strlen(path) == 0) { 1203 return NULL; 1204 } 1205 const char psepchar = *os::path_separator(); 1206 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1207 if (inpath == NULL) { 1208 return NULL; 1209 } 1210 strcpy(inpath, path); 1211 int count = 1; 1212 char* p = strchr(inpath, psepchar); 1213 // Get a count of elements to allocate memory 1214 while (p != NULL) { 1215 count++; 1216 p++; 1217 p = strchr(p, psepchar); 1218 } 1219 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1220 if (opath == NULL) { 1221 return NULL; 1222 } 1223 1224 // do the actual splitting 1225 p = inpath; 1226 for (int i = 0 ; i < count ; i++) { 1227 size_t len = strcspn(p, os::path_separator()); 1228 if (len > JVM_MAXPATHLEN) { 1229 return NULL; 1230 } 1231 // allocate the string and add terminator storage 1232 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1233 if (s == NULL) { 1234 return NULL; 1235 } 1236 strncpy(s, p, len); 1237 s[len] = '\0'; 1238 opath[i] = s; 1239 p += len + 1; 1240 } 1241 FREE_C_HEAP_ARRAY(char, inpath, mtInternal); 1242 *n = count; 1243 return opath; 1244} 1245 1246void os::set_memory_serialize_page(address page) { 1247 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1248 _mem_serialize_page = (volatile int32_t *)page; 1249 // We initialize the serialization page shift count here 1250 // We assume a cache line size of 64 bytes 1251 assert(SerializePageShiftCount == count, 1252 "thread size changed, fix SerializePageShiftCount constant"); 1253 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1254} 1255 1256static volatile intptr_t SerializePageLock = 0; 1257 1258// This method is called from signal handler when SIGSEGV occurs while the current 1259// thread tries to store to the "read-only" memory serialize page during state 1260// transition. 1261void os::block_on_serialize_page_trap() { 1262 if (TraceSafepoint) { 1263 tty->print_cr("Block until the serialize page permission restored"); 1264 } 1265 // When VMThread is holding the SerializePageLock during modifying the 1266 // access permission of the memory serialize page, the following call 1267 // will block until the permission of that page is restored to rw. 1268 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1269 // this case, it's OK as the signal is synchronous and we know precisely when 1270 // it can occur. 1271 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1272 Thread::muxRelease(&SerializePageLock); 1273} 1274 1275// Serialize all thread state variables 1276void os::serialize_thread_states() { 1277 // On some platforms such as Solaris & Linux, the time duration of the page 1278 // permission restoration is observed to be much longer than expected due to 1279 // scheduler starvation problem etc. To avoid the long synchronization 1280 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1281 // the mutator thread if such case is encountered. See bug 6546278 for details. 1282 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1283 os::protect_memory((char *)os::get_memory_serialize_page(), 1284 os::vm_page_size(), MEM_PROT_READ); 1285 os::protect_memory((char *)os::get_memory_serialize_page(), 1286 os::vm_page_size(), MEM_PROT_RW); 1287 Thread::muxRelease(&SerializePageLock); 1288} 1289 1290// Returns true if the current stack pointer is above the stack shadow 1291// pages, false otherwise. 1292 1293bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1294 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1295 address sp = current_stack_pointer(); 1296 // Check if we have StackShadowPages above the yellow zone. This parameter 1297 // is dependent on the depth of the maximum VM call stack possible from 1298 // the handler for stack overflow. 'instanceof' in the stack overflow 1299 // handler or a println uses at least 8k stack of VM and native code 1300 // respectively. 1301 const int framesize_in_bytes = 1302 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1303 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1304 * vm_page_size()) + framesize_in_bytes; 1305 // The very lower end of the stack 1306 address stack_limit = thread->stack_base() - thread->stack_size(); 1307 return (sp > (stack_limit + reserved_area)); 1308} 1309 1310size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, 1311 uint min_pages) 1312{ 1313 assert(min_pages > 0, "sanity"); 1314 if (UseLargePages) { 1315 const size_t max_page_size = region_max_size / min_pages; 1316 1317 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { 1318 const size_t sz = _page_sizes[i]; 1319 const size_t mask = sz - 1; 1320 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { 1321 // The largest page size with no fragmentation. 1322 return sz; 1323 } 1324 1325 if (sz <= max_page_size) { 1326 // The largest page size that satisfies the min_pages requirement. 1327 return sz; 1328 } 1329 } 1330 } 1331 1332 return vm_page_size(); 1333} 1334 1335#ifndef PRODUCT 1336void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1337{ 1338 if (TracePageSizes) { 1339 tty->print("%s: ", str); 1340 for (int i = 0; i < count; ++i) { 1341 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1342 } 1343 tty->cr(); 1344 } 1345} 1346 1347void os::trace_page_sizes(const char* str, const size_t region_min_size, 1348 const size_t region_max_size, const size_t page_size, 1349 const char* base, const size_t size) 1350{ 1351 if (TracePageSizes) { 1352 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1353 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1354 " size=" SIZE_FORMAT, 1355 str, region_min_size, region_max_size, 1356 page_size, base, size); 1357 } 1358} 1359#endif // #ifndef PRODUCT 1360 1361// This is the working definition of a server class machine: 1362// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1363// because the graphics memory (?) sometimes masks physical memory. 1364// If you want to change the definition of a server class machine 1365// on some OS or platform, e.g., >=4GB on Windohs platforms, 1366// then you'll have to parameterize this method based on that state, 1367// as was done for logical processors here, or replicate and 1368// specialize this method for each platform. (Or fix os to have 1369// some inheritance structure and use subclassing. Sigh.) 1370// If you want some platform to always or never behave as a server 1371// class machine, change the setting of AlwaysActAsServerClassMachine 1372// and NeverActAsServerClassMachine in globals*.hpp. 1373bool os::is_server_class_machine() { 1374 // First check for the early returns 1375 if (NeverActAsServerClassMachine) { 1376 return false; 1377 } 1378 if (AlwaysActAsServerClassMachine) { 1379 return true; 1380 } 1381 // Then actually look at the machine 1382 bool result = false; 1383 const unsigned int server_processors = 2; 1384 const julong server_memory = 2UL * G; 1385 // We seem not to get our full complement of memory. 1386 // We allow some part (1/8?) of the memory to be "missing", 1387 // based on the sizes of DIMMs, and maybe graphics cards. 1388 const julong missing_memory = 256UL * M; 1389 1390 /* Is this a server class machine? */ 1391 if ((os::active_processor_count() >= (int)server_processors) && 1392 (os::physical_memory() >= (server_memory - missing_memory))) { 1393 const unsigned int logical_processors = 1394 VM_Version::logical_processors_per_package(); 1395 if (logical_processors > 1) { 1396 const unsigned int physical_packages = 1397 os::active_processor_count() / logical_processors; 1398 if (physical_packages > server_processors) { 1399 result = true; 1400 } 1401 } else { 1402 result = true; 1403 } 1404 } 1405 return result; 1406} 1407 1408// Read file line by line, if line is longer than bsize, 1409// skip rest of line. 1410int os::get_line_chars(int fd, char* buf, const size_t bsize){ 1411 size_t sz, i = 0; 1412 1413 // read until EOF, EOL or buf is full 1414 while ((sz = (int) read(fd, &buf[i], 1)) == 1 && i < (bsize-2) && buf[i] != '\n') { 1415 ++i; 1416 } 1417 1418 if (buf[i] == '\n') { 1419 // EOL reached so ignore EOL character and return 1420 1421 buf[i] = 0; 1422 return (int) i; 1423 } 1424 1425 buf[i+1] = 0; 1426 1427 if (sz != 1) { 1428 // EOF reached. if we read chars before EOF return them and 1429 // return EOF on next call otherwise return EOF 1430 1431 return (i == 0) ? -1 : (int) i; 1432 } 1433 1434 // line is longer than size of buf, skip to EOL 1435 char ch; 1436 while (read(fd, &ch, 1) == 1 && ch != '\n') { 1437 // Do nothing 1438 } 1439 1440 // return initial part of line that fits in buf. 1441 // If we reached EOF, it will be returned on next call. 1442 1443 return (int) i; 1444} 1445 1446void os::SuspendedThreadTask::run() { 1447 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1448 internal_do_task(); 1449 _done = true; 1450} 1451 1452bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1453 return os::pd_create_stack_guard_pages(addr, bytes); 1454} 1455 1456char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1457 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1458 if (result != NULL) { 1459 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1460 } 1461 1462 return result; 1463} 1464 1465char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1466 MEMFLAGS flags) { 1467 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1468 if (result != NULL) { 1469 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1470 MemTracker::record_virtual_memory_type((address)result, flags); 1471 } 1472 1473 return result; 1474} 1475 1476char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1477 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1478 if (result != NULL) { 1479 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1480 } 1481 return result; 1482} 1483 1484void os::split_reserved_memory(char *base, size_t size, 1485 size_t split, bool realloc) { 1486 pd_split_reserved_memory(base, size, split, realloc); 1487} 1488 1489bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1490 bool res = pd_commit_memory(addr, bytes, executable); 1491 if (res) { 1492 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1493 } 1494 return res; 1495} 1496 1497bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1498 bool executable) { 1499 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1500 if (res) { 1501 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1502 } 1503 return res; 1504} 1505 1506bool os::uncommit_memory(char* addr, size_t bytes) { 1507 bool res = pd_uncommit_memory(addr, bytes); 1508 if (res) { 1509 MemTracker::record_virtual_memory_uncommit((address)addr, bytes); 1510 } 1511 return res; 1512} 1513 1514bool os::release_memory(char* addr, size_t bytes) { 1515 bool res = pd_release_memory(addr, bytes); 1516 if (res) { 1517 MemTracker::record_virtual_memory_release((address)addr, bytes); 1518 } 1519 return res; 1520} 1521 1522 1523char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1524 char *addr, size_t bytes, bool read_only, 1525 bool allow_exec) { 1526 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1527 if (result != NULL) { 1528 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1529 MemTracker::record_virtual_memory_commit((address)result, bytes, CALLER_PC); 1530 } 1531 return result; 1532} 1533 1534char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1535 char *addr, size_t bytes, bool read_only, 1536 bool allow_exec) { 1537 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1538 read_only, allow_exec); 1539} 1540 1541bool os::unmap_memory(char *addr, size_t bytes) { 1542 bool result = pd_unmap_memory(addr, bytes); 1543 if (result) { 1544 MemTracker::record_virtual_memory_uncommit((address)addr, bytes); 1545 MemTracker::record_virtual_memory_release((address)addr, bytes); 1546 } 1547 return result; 1548} 1549 1550void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1551 pd_free_memory(addr, bytes, alignment_hint); 1552} 1553 1554void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1555 pd_realign_memory(addr, bytes, alignment_hint); 1556} 1557 1558#ifndef TARGET_OS_FAMILY_windows 1559/* try to switch state from state "from" to state "to" 1560 * returns the state set after the method is complete 1561 */ 1562os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1563 os::SuspendResume::State to) 1564{ 1565 os::SuspendResume::State result = 1566 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1567 if (result == from) { 1568 // success 1569 return to; 1570 } 1571 return result; 1572} 1573#endif 1574