os.cpp revision 7462:a0dd995271c4
1159248Srwatson/* 2159248Srwatson * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. 3159248Srwatson * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4159248Srwatson * 5159248Srwatson * This code is free software; you can redistribute it and/or modify it 6159248Srwatson * under the terms of the GNU General Public License version 2 only, as 7159248Srwatson * published by the Free Software Foundation. 8159248Srwatson * 9159248Srwatson * This code is distributed in the hope that it will be useful, but WITHOUT 10159248Srwatson * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11159248Srwatson * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12159248Srwatson * version 2 for more details (a copy is included in the LICENSE file that 13159248Srwatson * accompanied this code). 14159248Srwatson * 15159248Srwatson * You should have received a copy of the GNU General Public License version 16159248Srwatson * 2 along with this work; if not, write to the Free Software Foundation, 17159248Srwatson * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18159248Srwatson * 19159248Srwatson * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20159248Srwatson * or visit www.oracle.com if you need additional information or have any 21159248Srwatson * questions. 22159248Srwatson * 23159248Srwatson */ 24159248Srwatson 25159248Srwatson#include "precompiled.hpp" 26159248Srwatson#include "classfile/classLoader.hpp" 27159248Srwatson#include "classfile/javaClasses.hpp" 28159248Srwatson#include "classfile/systemDictionary.hpp" 29161630Srwatson#include "classfile/vmSymbols.hpp" 30161630Srwatson#include "code/codeCache.hpp" 31161630Srwatson#include "code/icBuffer.hpp" 32161630Srwatson#include "code/vtableStubs.hpp" 33161630Srwatson#include "gc_implementation/shared/vmGCOperations.hpp" 34161630Srwatson#include "interpreter/interpreter.hpp" 35161630Srwatson#include "memory/allocation.inline.hpp" 36161630Srwatson#ifdef ASSERT 37161630Srwatson#include "memory/guardedMemory.hpp" 38159248Srwatson#endif 39159248Srwatson#include "oops/oop.inline.hpp" 40159248Srwatson#include "prims/jvm.h" 41159248Srwatson#include "prims/jvm_misc.hpp" 42159248Srwatson#include "prims/privilegedStack.hpp" 43159248Srwatson#include "runtime/arguments.hpp" 44159248Srwatson#include "runtime/atomic.inline.hpp" 45159248Srwatson#include "runtime/frame.inline.hpp" 46159248Srwatson#include "runtime/interfaceSupport.hpp" 47159248Srwatson#include "runtime/java.hpp" 48159248Srwatson#include "runtime/javaCalls.hpp" 49168777Srwatson#include "runtime/mutexLocker.hpp" 50168777Srwatson#include "runtime/os.inline.hpp" 51168777Srwatson#include "runtime/stubRoutines.hpp" 52168777Srwatson#include "runtime/thread.inline.hpp" 53159248Srwatson#include "runtime/vm_version.hpp" 54159248Srwatson#include "services/attachListener.hpp" 55185573Srwatson#include "services/nmtCommon.hpp" 56159248Srwatson#include "services/mallocTracker.hpp" 57159248Srwatson#include "services/memTracker.hpp" 58159248Srwatson#include "services/threadService.hpp" 59159248Srwatson#include "utilities/defaultStream.hpp" 60159248Srwatson#include "utilities/events.hpp" 61159248Srwatson 62159248Srwatson# include <signal.h> 63159248Srwatson 64159248SrwatsonPRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 65159248Srwatson 66159248SrwatsonOSThread* os::_starting_thread = NULL; 67159248Srwatsonaddress os::_polling_page = NULL; 68159248Srwatsonvolatile int32_t* os::_mem_serialize_page = NULL; 69159248Srwatsonuintptr_t os::_serialize_page_mask = 0; 70159248Srwatsonlong os::_rand_seed = 1; 71159248Srwatsonint os::_processor_count = 0; 72159248Srwatsonsize_t os::_page_sizes[os::page_sizes_max]; 73159248Srwatson 74159248Srwatson#ifndef PRODUCT 75159248Srwatsonjulong os::num_mallocs = 0; // # of calls to malloc/realloc 76159248Srwatsonjulong os::alloc_bytes = 0; // # of bytes allocated 77159248Srwatsonjulong os::num_frees = 0; // # of calls to free 78159248Srwatsonjulong os::free_bytes = 0; // # of bytes freed 79159248Srwatson#endif 80159248Srwatson 81159248Srwatsonstatic juint cur_malloc_words = 0; // current size for MallocMaxTestWords 82168777Srwatson 83159248Srwatsonvoid os_init_globals() { 84159248Srwatson // Called from init_globals(). 85159248Srwatson // See Threads::create_vm() in thread.cpp, and init.cpp. 86159248Srwatson os::init_globals(); 87159248Srwatson} 88159248Srwatson 89159248Srwatson// Fill in buffer with current local time as an ISO-8601 string. 90159248Srwatson// E.g., yyyy-mm-ddThh:mm:ss-zzzz. 91159248Srwatson// Returns buffer, or NULL if it failed. 92159248Srwatson// This would mostly be a call to 93159248Srwatson// strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) 94159248Srwatson// except that on Windows the %z behaves badly, so we do it ourselves. 95159248Srwatson// Also, people wanted milliseconds on there, 96159248Srwatson// and strftime doesn't do milliseconds. 97159248Srwatsonchar* os::iso8601_time(char* buffer, size_t buffer_length) { 98159248Srwatson // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" 99159248Srwatson // 1 2 100159248Srwatson // 12345678901234567890123456789 101159248Srwatson static const char* iso8601_format = 102159248Srwatson "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; 103159248Srwatson static const size_t needed_buffer = 29; 104159248Srwatson 105159248Srwatson // Sanity check the arguments 106159248Srwatson if (buffer == NULL) { 107159248Srwatson assert(false, "NULL buffer"); 108159248Srwatson return NULL; 109159248Srwatson } 110159248Srwatson if (buffer_length < needed_buffer) { 111159248Srwatson assert(false, "buffer_length too small"); 112159248Srwatson return NULL; 113159248Srwatson } 114159248Srwatson // Get the current time 115159248Srwatson jlong milliseconds_since_19700101 = javaTimeMillis(); 116159248Srwatson const int milliseconds_per_microsecond = 1000; 117159248Srwatson const time_t seconds_since_19700101 = 118159248Srwatson milliseconds_since_19700101 / milliseconds_per_microsecond; 119159248Srwatson const int milliseconds_after_second = 120159248Srwatson milliseconds_since_19700101 % milliseconds_per_microsecond; 121161630Srwatson // Convert the time value to a tm and timezone variable 122159248Srwatson struct tm time_struct; 123159248Srwatson if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) { 124159248Srwatson assert(false, "Failed localtime_pd"); 125159248Srwatson return NULL; 126161630Srwatson } 127161630Srwatson#if defined(_ALLBSD_SOURCE) 128159248Srwatson const time_t zone = (time_t) time_struct.tm_gmtoff; 129159248Srwatson#else 130159248Srwatson const time_t zone = timezone; 131159248Srwatson#endif 132293161Sbrueffer 133159248Srwatson // If daylight savings time is in effect, 134159248Srwatson // we are 1 hour East of our time zone 135159248Srwatson const time_t seconds_per_minute = 60; 136159248Srwatson const time_t minutes_per_hour = 60; 137159248Srwatson const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; 138159248Srwatson time_t UTC_to_local = zone; 139159248Srwatson if (time_struct.tm_isdst > 0) { 140159248Srwatson UTC_to_local = UTC_to_local - seconds_per_hour; 141159248Srwatson } 142159248Srwatson // Compute the time zone offset. 143159248Srwatson // localtime_pd() sets timezone to the difference (in seconds) 144159248Srwatson // between UTC and and local time. 145159248Srwatson // ISO 8601 says we need the difference between local time and UTC, 146159248Srwatson // we change the sign of the localtime_pd() result. 147159248Srwatson const time_t local_to_UTC = -(UTC_to_local); 148159248Srwatson // Then we have to figure out if if we are ahead (+) or behind (-) UTC. 149159248Srwatson char sign_local_to_UTC = '+'; 150159248Srwatson time_t abs_local_to_UTC = local_to_UTC; 151159248Srwatson if (local_to_UTC < 0) { 152159248Srwatson sign_local_to_UTC = '-'; 153159248Srwatson abs_local_to_UTC = -(abs_local_to_UTC); 154159248Srwatson } 155161630Srwatson // Convert time zone offset seconds to hours and minutes. 156159248Srwatson const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); 157159248Srwatson const time_t zone_min = 158159248Srwatson ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); 159159248Srwatson 160159248Srwatson // Print an ISO 8601 date and time stamp into the buffer 161159248Srwatson const int year = 1900 + time_struct.tm_year; 162159248Srwatson const int month = 1 + time_struct.tm_mon; 163159248Srwatson const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, 164159248Srwatson year, 165159248Srwatson month, 166159248Srwatson time_struct.tm_mday, 167159248Srwatson time_struct.tm_hour, 168159248Srwatson time_struct.tm_min, 169159248Srwatson time_struct.tm_sec, 170159248Srwatson milliseconds_after_second, 171159248Srwatson sign_local_to_UTC, 172159248Srwatson zone_hours, 173159248Srwatson zone_min); 174159248Srwatson if (printed == 0) { 175159248Srwatson assert(false, "Failed jio_printf"); 176159248Srwatson return NULL; 177159248Srwatson } 178159248Srwatson return buffer; 179159248Srwatson} 180159248Srwatson 181159248SrwatsonOSReturn os::set_priority(Thread* thread, ThreadPriority p) { 182159248Srwatson#ifdef ASSERT 183159248Srwatson if (!(!thread->is_Java_thread() || 184159248Srwatson Thread::current() == thread || 185159248Srwatson Threads_lock->owned_by_self() 186159248Srwatson || thread->is_Compiler_thread() 187159248Srwatson )) { 188159248Srwatson assert(false, "possibility of dangling Thread pointer"); 189159248Srwatson } 190159248Srwatson#endif 191159248Srwatson 192159248Srwatson if (p >= MinPriority && p <= MaxPriority) { 193159248Srwatson int priority = java_to_os_priority[p]; 194159248Srwatson return set_native_priority(thread, priority); 195159248Srwatson } else { 196159248Srwatson assert(false, "Should not happen"); 197159248Srwatson return OS_ERR; 198159248Srwatson } 199159248Srwatson} 200159248Srwatson 201159248Srwatson// The mapping from OS priority back to Java priority may be inexact because 202159248Srwatson// Java priorities can map M:1 with native priorities. If you want the definite 203159248Srwatson// Java priority then use JavaThread::java_priority() 204159248SrwatsonOSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { 205161630Srwatson int p; 206159248Srwatson int os_prio; 207159248Srwatson OSReturn ret = get_native_priority(thread, &os_prio); 208159248Srwatson if (ret != OS_OK) return ret; 209159248Srwatson 210159248Srwatson if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) { 211159248Srwatson for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; 212159248Srwatson } else { 213159248Srwatson // niceness values are in reverse order 214159248Srwatson for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ; 215159248Srwatson } 216159248Srwatson priority = (ThreadPriority)p; 217159248Srwatson return OS_OK; 218185573Srwatson} 219159248Srwatson 220159248Srwatson 221159248Srwatson// --------------------- sun.misc.Signal (optional) --------------------- 222159248Srwatson 223159248Srwatson 224159248Srwatson// SIGBREAK is sent by the keyboard to query the VM state 225159248Srwatson#ifndef SIGBREAK 226159248Srwatson#define SIGBREAK SIGQUIT 227159248Srwatson#endif 228159248Srwatson 229159248Srwatson// sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. 230159248Srwatson 231159248Srwatson 232159248Srwatsonstatic void signal_thread_entry(JavaThread* thread, TRAPS) { 233159248Srwatson os::set_priority(thread, NearMaxPriority); 234159248Srwatson while (true) { 235159248Srwatson int sig; 236159248Srwatson { 237159248Srwatson // FIXME : Currently we have not decided what should be the status 238159248Srwatson // for this java thread blocked here. Once we decide about 239159248Srwatson // that we should fix this. 240159248Srwatson sig = os::signal_wait(); 241159248Srwatson } 242159248Srwatson if (sig == os::sigexitnum_pd()) { 243159248Srwatson // Terminate the signal thread 244159248Srwatson return; 245159248Srwatson } 246159248Srwatson 247159248Srwatson switch (sig) { 248159248Srwatson case SIGBREAK: { 249159248Srwatson // Check if the signal is a trigger to start the Attach Listener - in that 250159248Srwatson // case don't print stack traces. 251159248Srwatson if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { 252159248Srwatson continue; 253159248Srwatson } 254159248Srwatson // Print stack traces 255161630Srwatson // Any SIGBREAK operations added here should make sure to flush 256159248Srwatson // the output stream (e.g. tty->flush()) after output. See 4803766. 257159248Srwatson // Each module also prints an extra carriage return after its output. 258159248Srwatson VM_PrintThreads op; 259159248Srwatson VMThread::execute(&op); 260159248Srwatson VM_PrintJNI jni_op; 261159248Srwatson VMThread::execute(&jni_op); 262159248Srwatson VM_FindDeadlocks op1(tty); 263159248Srwatson VMThread::execute(&op1); 264159248Srwatson Universe::print_heap_at_SIGBREAK(); 265159248Srwatson if (PrintClassHistogram) { 266159248Srwatson VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */); 267159248Srwatson VMThread::execute(&op1); 268159248Srwatson } 269159248Srwatson if (JvmtiExport::should_post_data_dump()) { 270159248Srwatson JvmtiExport::post_data_dump(); 271159248Srwatson } 272159248Srwatson break; 273159248Srwatson } 274159248Srwatson default: { 275159248Srwatson // Dispatch the signal to java 276159248Srwatson HandleMark hm(THREAD); 277159248Srwatson Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD); 278159248Srwatson KlassHandle klass (THREAD, k); 279159248Srwatson if (klass.not_null()) { 280159248Srwatson JavaValue result(T_VOID); 281159248Srwatson JavaCallArguments args; 282159248Srwatson args.push_int(sig); 283159248Srwatson JavaCalls::call_static( 284159248Srwatson &result, 285159248Srwatson klass, 286159248Srwatson vmSymbols::dispatch_name(), 287159248Srwatson vmSymbols::int_void_signature(), 288159248Srwatson &args, 289159248Srwatson THREAD 290159248Srwatson ); 291159248Srwatson } 292159248Srwatson if (HAS_PENDING_EXCEPTION) { 293159248Srwatson // tty is initialized early so we don't expect it to be null, but 294159248Srwatson // if it is we can't risk doing an initialization that might 295159248Srwatson // trigger additional out-of-memory conditions 296159248Srwatson if (tty != NULL) { 297159248Srwatson char klass_name[256]; 298159248Srwatson char tmp_sig_name[16]; 299159248Srwatson const char* sig_name = "UNKNOWN"; 300159248Srwatson InstanceKlass::cast(PENDING_EXCEPTION->klass())-> 301159248Srwatson name()->as_klass_external_name(klass_name, 256); 302159248Srwatson if (os::exception_name(sig, tmp_sig_name, 16) != NULL) 303159248Srwatson sig_name = tmp_sig_name; 304159248Srwatson warning("Exception %s occurred dispatching signal %s to handler" 305159248Srwatson "- the VM may need to be forcibly terminated", 306159248Srwatson klass_name, sig_name ); 307159248Srwatson } 308159248Srwatson CLEAR_PENDING_EXCEPTION; 309159248Srwatson } 310159248Srwatson } 311159248Srwatson } 312159248Srwatson } 313159248Srwatson} 314159248Srwatson 315159248Srwatsonvoid os::init_before_ergo() { 316159248Srwatson // We need to initialize large page support here because ergonomics takes some 317159248Srwatson // decisions depending on large page support and the calculated large page size. 318159248Srwatson large_page_init(); 319159248Srwatson} 320159248Srwatson 321159248Srwatsonvoid os::signal_init() { 322159248Srwatson if (!ReduceSignalUsage) { 323159248Srwatson // Setup JavaThread for processing signals 324159248Srwatson EXCEPTION_MARK; 325159248Srwatson Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); 326159248Srwatson instanceKlassHandle klass (THREAD, k); 327159248Srwatson instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); 328159248Srwatson 329159248Srwatson const char thread_name[] = "Signal Dispatcher"; 330159248Srwatson Handle string = java_lang_String::create_from_str(thread_name, CHECK); 331159248Srwatson 332159248Srwatson // Initialize thread_oop to put it into the system threadGroup 333159248Srwatson Handle thread_group (THREAD, Universe::system_thread_group()); 334159248Srwatson JavaValue result(T_VOID); 335159248Srwatson JavaCalls::call_special(&result, thread_oop, 336159248Srwatson klass, 337159248Srwatson vmSymbols::object_initializer_name(), 338159248Srwatson vmSymbols::threadgroup_string_void_signature(), 339159248Srwatson thread_group, 340159248Srwatson string, 341159248Srwatson CHECK); 342159248Srwatson 343159248Srwatson KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); 344159248Srwatson JavaCalls::call_special(&result, 345159248Srwatson thread_group, 346159248Srwatson group, 347159248Srwatson vmSymbols::add_method_name(), 348159248Srwatson vmSymbols::thread_void_signature(), 349159248Srwatson thread_oop, // ARG 1 350159248Srwatson CHECK); 351159248Srwatson 352159248Srwatson os::signal_init_pd(); 353 354 { MutexLocker mu(Threads_lock); 355 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); 356 357 // At this point it may be possible that no osthread was created for the 358 // JavaThread due to lack of memory. We would have to throw an exception 359 // in that case. However, since this must work and we do not allow 360 // exceptions anyway, check and abort if this fails. 361 if (signal_thread == NULL || signal_thread->osthread() == NULL) { 362 vm_exit_during_initialization("java.lang.OutOfMemoryError", 363 os::native_thread_creation_failed_msg()); 364 } 365 366 java_lang_Thread::set_thread(thread_oop(), signal_thread); 367 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); 368 java_lang_Thread::set_daemon(thread_oop()); 369 370 signal_thread->set_threadObj(thread_oop()); 371 Threads::add(signal_thread); 372 Thread::start(signal_thread); 373 } 374 // Handle ^BREAK 375 os::signal(SIGBREAK, os::user_handler()); 376 } 377} 378 379 380void os::terminate_signal_thread() { 381 if (!ReduceSignalUsage) 382 signal_notify(sigexitnum_pd()); 383} 384 385 386// --------------------- loading libraries --------------------- 387 388typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); 389extern struct JavaVM_ main_vm; 390 391static void* _native_java_library = NULL; 392 393void* os::native_java_library() { 394 if (_native_java_library == NULL) { 395 char buffer[JVM_MAXPATHLEN]; 396 char ebuf[1024]; 397 398 // Try to load verify dll first. In 1.3 java dll depends on it and is not 399 // always able to find it when the loading executable is outside the JDK. 400 // In order to keep working with 1.2 we ignore any loading errors. 401 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 402 "verify")) { 403 dll_load(buffer, ebuf, sizeof(ebuf)); 404 } 405 406 // Load java dll 407 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 408 "java")) { 409 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); 410 } 411 if (_native_java_library == NULL) { 412 vm_exit_during_initialization("Unable to load native library", ebuf); 413 } 414 415#if defined(__OpenBSD__) 416 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so 417 // ignore errors 418 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), 419 "net")) { 420 dll_load(buffer, ebuf, sizeof(ebuf)); 421 } 422#endif 423 } 424 static jboolean onLoaded = JNI_FALSE; 425 if (onLoaded) { 426 // We may have to wait to fire OnLoad until TLS is initialized. 427 if (ThreadLocalStorage::is_initialized()) { 428 // The JNI_OnLoad handling is normally done by method load in 429 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library 430 // explicitly so we have to check for JNI_OnLoad as well 431 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; 432 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( 433 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); 434 if (JNI_OnLoad != NULL) { 435 JavaThread* thread = JavaThread::current(); 436 ThreadToNativeFromVM ttn(thread); 437 HandleMark hm(thread); 438 jint ver = (*JNI_OnLoad)(&main_vm, NULL); 439 onLoaded = JNI_TRUE; 440 if (!Threads::is_supported_jni_version_including_1_1(ver)) { 441 vm_exit_during_initialization("Unsupported JNI version"); 442 } 443 } 444 } 445 } 446 return _native_java_library; 447} 448 449/* 450 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists. 451 * If check_lib == true then we are looking for an 452 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if 453 * this library is statically linked into the image. 454 * If check_lib == false then we will look for the appropriate symbol in the 455 * executable if agent_lib->is_static_lib() == true or in the shared library 456 * referenced by 'handle'. 457 */ 458void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib, 459 const char *syms[], size_t syms_len) { 460 assert(agent_lib != NULL, "sanity check"); 461 const char *lib_name; 462 void *handle = agent_lib->os_lib(); 463 void *entryName = NULL; 464 char *agent_function_name; 465 size_t i; 466 467 // If checking then use the agent name otherwise test is_static_lib() to 468 // see how to process this lookup 469 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL); 470 for (i = 0; i < syms_len; i++) { 471 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path()); 472 if (agent_function_name == NULL) { 473 break; 474 } 475 entryName = dll_lookup(handle, agent_function_name); 476 FREE_C_HEAP_ARRAY(char, agent_function_name); 477 if (entryName != NULL) { 478 break; 479 } 480 } 481 return entryName; 482} 483 484// See if the passed in agent is statically linked into the VM image. 485bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 486 size_t syms_len) { 487 void *ret; 488 void *proc_handle; 489 void *save_handle; 490 491 assert(agent_lib != NULL, "sanity check"); 492 if (agent_lib->name() == NULL) { 493 return false; 494 } 495 proc_handle = get_default_process_handle(); 496 // Check for Agent_OnLoad/Attach_lib_name function 497 save_handle = agent_lib->os_lib(); 498 // We want to look in this process' symbol table. 499 agent_lib->set_os_lib(proc_handle); 500 ret = find_agent_function(agent_lib, true, syms, syms_len); 501 if (ret != NULL) { 502 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent 503 agent_lib->set_valid(); 504 agent_lib->set_static_lib(true); 505 return true; 506 } 507 agent_lib->set_os_lib(save_handle); 508 return false; 509} 510 511// --------------------- heap allocation utilities --------------------- 512 513char *os::strdup(const char *str, MEMFLAGS flags) { 514 size_t size = strlen(str); 515 char *dup_str = (char *)malloc(size + 1, flags); 516 if (dup_str == NULL) return NULL; 517 strcpy(dup_str, str); 518 return dup_str; 519} 520 521char* os::strdup_check_oom(const char* str, MEMFLAGS flags) { 522 char* p = os::strdup(str, flags); 523 if (p == NULL) { 524 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom"); 525 } 526 return p; 527} 528 529 530#define paranoid 0 /* only set to 1 if you suspect checking code has bug */ 531 532#ifdef ASSERT 533 534static void verify_memory(void* ptr) { 535 GuardedMemory guarded(ptr); 536 if (!guarded.verify_guards()) { 537 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees); 538 tty->print_cr("## memory stomp:"); 539 guarded.print_on(tty); 540 fatal("memory stomping error"); 541 } 542} 543 544#endif 545 546// 547// This function supports testing of the malloc out of memory 548// condition without really running the system out of memory. 549// 550static u_char* testMalloc(size_t alloc_size) { 551 assert(MallocMaxTestWords > 0, "sanity check"); 552 553 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) { 554 return NULL; 555 } 556 557 u_char* ptr = (u_char*)::malloc(alloc_size); 558 559 if (ptr != NULL) { 560 Atomic::add(((jint) (alloc_size / BytesPerWord)), 561 (volatile jint *) &cur_malloc_words); 562 } 563 return ptr; 564} 565 566void* os::malloc(size_t size, MEMFLAGS flags) { 567 return os::malloc(size, flags, CALLER_PC); 568} 569 570void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 571 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 572 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 573 574#ifdef ASSERT 575 // checking for the WatcherThread and crash_protection first 576 // since os::malloc can be called when the libjvm.{dll,so} is 577 // first loaded and we don't have a thread yet. 578 // try to find the thread after we see that the watcher thread 579 // exists and has crash protection. 580 WatcherThread *wt = WatcherThread::watcher_thread(); 581 if (wt != NULL && wt->has_crash_protection()) { 582 Thread* thread = ThreadLocalStorage::get_thread_slow(); 583 if (thread == wt) { 584 assert(!wt->has_crash_protection(), 585 "Can't malloc with crash protection from WatcherThread"); 586 } 587 } 588#endif 589 590 if (size == 0) { 591 // return a valid pointer if size is zero 592 // if NULL is returned the calling functions assume out of memory. 593 size = 1; 594 } 595 596 // NMT support 597 NMT_TrackingLevel level = MemTracker::tracking_level(); 598 size_t nmt_header_size = MemTracker::malloc_header_size(level); 599 600#ifndef ASSERT 601 const size_t alloc_size = size + nmt_header_size; 602#else 603 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size); 604 if (size + nmt_header_size > alloc_size) { // Check for rollover. 605 return NULL; 606 } 607#endif 608 609 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 610 611 u_char* ptr; 612 if (MallocMaxTestWords > 0) { 613 ptr = testMalloc(alloc_size); 614 } else { 615 ptr = (u_char*)::malloc(alloc_size); 616 } 617 618#ifdef ASSERT 619 if (ptr == NULL) { 620 return NULL; 621 } 622 // Wrap memory with guard 623 GuardedMemory guarded(ptr, size + nmt_header_size); 624 ptr = guarded.get_user_ptr(); 625#endif 626 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 627 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 628 breakpoint(); 629 } 630 debug_only(if (paranoid) verify_memory(ptr)); 631 if (PrintMalloc && tty != NULL) { 632 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 633 } 634 635 // we do not track guard memory 636 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level); 637} 638 639void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) { 640 return os::realloc(memblock, size, flags, CALLER_PC); 641} 642 643void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) { 644 645#ifndef ASSERT 646 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1)); 647 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size)); 648 // NMT support 649 void* membase = MemTracker::record_free(memblock); 650 NMT_TrackingLevel level = MemTracker::tracking_level(); 651 size_t nmt_header_size = MemTracker::malloc_header_size(level); 652 void* ptr = ::realloc(membase, size + nmt_header_size); 653 return MemTracker::record_malloc(ptr, size, memflags, stack, level); 654#else 655 if (memblock == NULL) { 656 return os::malloc(size, memflags, stack); 657 } 658 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 659 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock); 660 breakpoint(); 661 } 662 // NMT support 663 void* membase = MemTracker::malloc_base(memblock); 664 verify_memory(membase); 665 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 666 if (size == 0) { 667 return NULL; 668 } 669 // always move the block 670 void* ptr = os::malloc(size, memflags, stack); 671 if (PrintMalloc) { 672 tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr); 673 } 674 // Copy to new memory if malloc didn't fail 675 if ( ptr != NULL ) { 676 GuardedMemory guarded(MemTracker::malloc_base(memblock)); 677 // Guard's user data contains NMT header 678 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock); 679 memcpy(ptr, memblock, MIN2(size, memblock_size)); 680 if (paranoid) verify_memory(MemTracker::malloc_base(ptr)); 681 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { 682 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr); 683 breakpoint(); 684 } 685 os::free(memblock); 686 } 687 return ptr; 688#endif 689} 690 691 692void os::free(void *memblock) { 693 NOT_PRODUCT(inc_stat_counter(&num_frees, 1)); 694#ifdef ASSERT 695 if (memblock == NULL) return; 696 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { 697 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock); 698 breakpoint(); 699 } 700 void* membase = MemTracker::record_free(memblock); 701 verify_memory(membase); 702 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); 703 704 GuardedMemory guarded(membase); 705 size_t size = guarded.get_user_size(); 706 inc_stat_counter(&free_bytes, size); 707 membase = guarded.release_for_freeing(); 708 if (PrintMalloc && tty != NULL) { 709 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase); 710 } 711 ::free(membase); 712#else 713 void* membase = MemTracker::record_free(memblock); 714 ::free(membase); 715#endif 716} 717 718void os::init_random(long initval) { 719 _rand_seed = initval; 720} 721 722 723long os::random() { 724 /* standard, well-known linear congruential random generator with 725 * next_rand = (16807*seed) mod (2**31-1) 726 * see 727 * (1) "Random Number Generators: Good Ones Are Hard to Find", 728 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), 729 * (2) "Two Fast Implementations of the 'Minimal Standard' Random 730 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. 731 */ 732 const long a = 16807; 733 const unsigned long m = 2147483647; 734 const long q = m / a; assert(q == 127773, "weird math"); 735 const long r = m % a; assert(r == 2836, "weird math"); 736 737 // compute az=2^31p+q 738 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); 739 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); 740 lo += (hi & 0x7FFF) << 16; 741 742 // if q overflowed, ignore the overflow and increment q 743 if (lo > m) { 744 lo &= m; 745 ++lo; 746 } 747 lo += hi >> 15; 748 749 // if (p+q) overflowed, ignore the overflow and increment (p+q) 750 if (lo > m) { 751 lo &= m; 752 ++lo; 753 } 754 return (_rand_seed = lo); 755} 756 757// The INITIALIZED state is distinguished from the SUSPENDED state because the 758// conditions in which a thread is first started are different from those in which 759// a suspension is resumed. These differences make it hard for us to apply the 760// tougher checks when starting threads that we want to do when resuming them. 761// However, when start_thread is called as a result of Thread.start, on a Java 762// thread, the operation is synchronized on the Java Thread object. So there 763// cannot be a race to start the thread and hence for the thread to exit while 764// we are working on it. Non-Java threads that start Java threads either have 765// to do so in a context in which races are impossible, or should do appropriate 766// locking. 767 768void os::start_thread(Thread* thread) { 769 // guard suspend/resume 770 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); 771 OSThread* osthread = thread->osthread(); 772 osthread->set_state(RUNNABLE); 773 pd_start_thread(thread); 774} 775 776//--------------------------------------------------------------------------- 777// Helper functions for fatal error handler 778 779void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { 780 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); 781 782 int cols = 0; 783 int cols_per_line = 0; 784 switch (unitsize) { 785 case 1: cols_per_line = 16; break; 786 case 2: cols_per_line = 8; break; 787 case 4: cols_per_line = 4; break; 788 case 8: cols_per_line = 2; break; 789 default: return; 790 } 791 792 address p = start; 793 st->print(PTR_FORMAT ": ", start); 794 while (p < end) { 795 switch (unitsize) { 796 case 1: st->print("%02x", *(u1*)p); break; 797 case 2: st->print("%04x", *(u2*)p); break; 798 case 4: st->print("%08x", *(u4*)p); break; 799 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; 800 } 801 p += unitsize; 802 cols++; 803 if (cols >= cols_per_line && p < end) { 804 cols = 0; 805 st->cr(); 806 st->print(PTR_FORMAT ": ", p); 807 } else { 808 st->print(" "); 809 } 810 } 811 st->cr(); 812} 813 814void os::print_environment_variables(outputStream* st, const char** env_list, 815 char* buffer, int len) { 816 if (env_list) { 817 st->print_cr("Environment Variables:"); 818 819 for (int i = 0; env_list[i] != NULL; i++) { 820 if (getenv(env_list[i], buffer, len)) { 821 st->print("%s", env_list[i]); 822 st->print("="); 823 st->print_cr("%s", buffer); 824 } 825 } 826 } 827} 828 829void os::print_cpu_info(outputStream* st) { 830 // cpu 831 st->print("CPU:"); 832 st->print("total %d", os::processor_count()); 833 // It's not safe to query number of active processors after crash 834 // st->print("(active %d)", os::active_processor_count()); 835 st->print(" %s", VM_Version::cpu_features()); 836 st->cr(); 837 pd_print_cpu_info(st); 838} 839 840void os::print_date_and_time(outputStream *st) { 841 const int secs_per_day = 86400; 842 const int secs_per_hour = 3600; 843 const int secs_per_min = 60; 844 845 time_t tloc; 846 (void)time(&tloc); 847 st->print("time: %s", ctime(&tloc)); // ctime adds newline. 848 849 double t = os::elapsedTime(); 850 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in 851 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int 852 // before printf. We lost some precision, but who cares? 853 int eltime = (int)t; // elapsed time in seconds 854 855 // print elapsed time in a human-readable format: 856 int eldays = eltime / secs_per_day; 857 int day_secs = eldays * secs_per_day; 858 int elhours = (eltime - day_secs) / secs_per_hour; 859 int hour_secs = elhours * secs_per_hour; 860 int elmins = (eltime - day_secs - hour_secs) / secs_per_min; 861 int minute_secs = elmins * secs_per_min; 862 int elsecs = (eltime - day_secs - hour_secs - minute_secs); 863 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs); 864} 865 866// moved from debug.cpp (used to be find()) but still called from there 867// The verbose parameter is only set by the debug code in one case 868void os::print_location(outputStream* st, intptr_t x, bool verbose) { 869 address addr = (address)x; 870 CodeBlob* b = CodeCache::find_blob_unsafe(addr); 871 if (b != NULL) { 872 if (b->is_buffer_blob()) { 873 // the interpreter is generated into a buffer blob 874 InterpreterCodelet* i = Interpreter::codelet_containing(addr); 875 if (i != NULL) { 876 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin())); 877 i->print_on(st); 878 return; 879 } 880 if (Interpreter::contains(addr)) { 881 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code" 882 " (not bytecode specific)", addr); 883 return; 884 } 885 // 886 if (AdapterHandlerLibrary::contains(b)) { 887 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin())); 888 AdapterHandlerLibrary::print_handler_on(st, b); 889 } 890 // the stubroutines are generated into a buffer blob 891 StubCodeDesc* d = StubCodeDesc::desc_for(addr); 892 if (d != NULL) { 893 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin())); 894 d->print_on(st); 895 st->cr(); 896 return; 897 } 898 if (StubRoutines::contains(addr)) { 899 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) " 900 "stub routine", addr); 901 return; 902 } 903 // the InlineCacheBuffer is using stubs generated into a buffer blob 904 if (InlineCacheBuffer::contains(addr)) { 905 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr); 906 return; 907 } 908 VtableStub* v = VtableStubs::stub_containing(addr); 909 if (v != NULL) { 910 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point())); 911 v->print_on(st); 912 st->cr(); 913 return; 914 } 915 } 916 nmethod* nm = b->as_nmethod_or_null(); 917 if (nm != NULL) { 918 ResourceMark rm; 919 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT, 920 addr, (int)(addr - nm->entry_point()), nm); 921 if (verbose) { 922 st->print(" for "); 923 nm->method()->print_value_on(st); 924 } 925 st->cr(); 926 nm->print_nmethod(verbose); 927 return; 928 } 929 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin())); 930 b->print_on(st); 931 return; 932 } 933 934 if (Universe::heap()->is_in(addr)) { 935 HeapWord* p = Universe::heap()->block_start(addr); 936 bool print = false; 937 // If we couldn't find it it just may mean that heap wasn't parsable 938 // See if we were just given an oop directly 939 if (p != NULL && Universe::heap()->block_is_obj(p)) { 940 print = true; 941 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) { 942 p = (HeapWord*) addr; 943 print = true; 944 } 945 if (print) { 946 if (p == (HeapWord*) addr) { 947 st->print_cr(INTPTR_FORMAT " is an oop", addr); 948 } else { 949 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p); 950 } 951 oop(p)->print_on(st); 952 return; 953 } 954 } else { 955 if (Universe::heap()->is_in_reserved(addr)) { 956 st->print_cr(INTPTR_FORMAT " is an unallocated location " 957 "in the heap", addr); 958 return; 959 } 960 } 961 if (JNIHandles::is_global_handle((jobject) addr)) { 962 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr); 963 return; 964 } 965 if (JNIHandles::is_weak_global_handle((jobject) addr)) { 966 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr); 967 return; 968 } 969#ifndef PRODUCT 970 // we don't keep the block list in product mode 971 if (JNIHandleBlock::any_contains((jobject) addr)) { 972 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr); 973 return; 974 } 975#endif 976 977 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { 978 // Check for privilege stack 979 if (thread->privileged_stack_top() != NULL && 980 thread->privileged_stack_top()->contains(addr)) { 981 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack " 982 "for thread: " INTPTR_FORMAT, addr, thread); 983 if (verbose) thread->print_on(st); 984 return; 985 } 986 // If the addr is a java thread print information about that. 987 if (addr == (address)thread) { 988 if (verbose) { 989 thread->print_on(st); 990 } else { 991 st->print_cr(INTPTR_FORMAT " is a thread", addr); 992 } 993 return; 994 } 995 // If the addr is in the stack region for this thread then report that 996 // and print thread info 997 if (thread->stack_base() >= addr && 998 addr > (thread->stack_base() - thread->stack_size())) { 999 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: " 1000 INTPTR_FORMAT, addr, thread); 1001 if (verbose) thread->print_on(st); 1002 return; 1003 } 1004 1005 } 1006 1007 // Check if in metaspace and print types that have vptrs (only method now) 1008 if (Metaspace::contains(addr)) { 1009 if (Method::has_method_vptr((const void*)addr)) { 1010 ((Method*)addr)->print_value_on(st); 1011 st->cr(); 1012 } else { 1013 // Use addr->print() from the debugger instead (not here) 1014 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr); 1015 } 1016 return; 1017 } 1018 1019 // Try an OS specific find 1020 if (os::find(addr, st)) { 1021 return; 1022 } 1023 1024 st->print_cr(INTPTR_FORMAT " is an unknown value", addr); 1025} 1026 1027// Looks like all platforms except IA64 can use the same function to check 1028// if C stack is walkable beyond current frame. The check for fp() is not 1029// necessary on Sparc, but it's harmless. 1030bool os::is_first_C_frame(frame* fr) { 1031#if (defined(IA64) && !defined(AIX)) && !defined(_WIN32) 1032 // On IA64 we have to check if the callers bsp is still valid 1033 // (i.e. within the register stack bounds). 1034 // Notice: this only works for threads created by the VM and only if 1035 // we walk the current stack!!! If we want to be able to walk 1036 // arbitrary other threads, we'll have to somehow store the thread 1037 // object in the frame. 1038 Thread *thread = Thread::current(); 1039 if ((address)fr->fp() <= 1040 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) { 1041 // This check is a little hacky, because on Linux the first C 1042 // frame's ('start_thread') register stack frame starts at 1043 // "register_stack_base + 0x48" while on HPUX, the first C frame's 1044 // ('__pthread_bound_body') register stack frame seems to really 1045 // start at "register_stack_base". 1046 return true; 1047 } else { 1048 return false; 1049 } 1050#elif defined(IA64) && defined(_WIN32) 1051 return true; 1052#else 1053 // Load up sp, fp, sender sp and sender fp, check for reasonable values. 1054 // Check usp first, because if that's bad the other accessors may fault 1055 // on some architectures. Ditto ufp second, etc. 1056 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); 1057 // sp on amd can be 32 bit aligned. 1058 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); 1059 1060 uintptr_t usp = (uintptr_t)fr->sp(); 1061 if ((usp & sp_align_mask) != 0) return true; 1062 1063 uintptr_t ufp = (uintptr_t)fr->fp(); 1064 if ((ufp & fp_align_mask) != 0) return true; 1065 1066 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); 1067 if ((old_sp & sp_align_mask) != 0) return true; 1068 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; 1069 1070 uintptr_t old_fp = (uintptr_t)fr->link(); 1071 if ((old_fp & fp_align_mask) != 0) return true; 1072 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; 1073 1074 // stack grows downwards; if old_fp is below current fp or if the stack 1075 // frame is too large, either the stack is corrupted or fp is not saved 1076 // on stack (i.e. on x86, ebp may be used as general register). The stack 1077 // is not walkable beyond current frame. 1078 if (old_fp < ufp) return true; 1079 if (old_fp - ufp > 64 * K) return true; 1080 1081 return false; 1082#endif 1083} 1084 1085#ifdef ASSERT 1086extern "C" void test_random() { 1087 const double m = 2147483647; 1088 double mean = 0.0, variance = 0.0, t; 1089 long reps = 10000; 1090 unsigned long seed = 1; 1091 1092 tty->print_cr("seed %ld for %ld repeats...", seed, reps); 1093 os::init_random(seed); 1094 long num; 1095 for (int k = 0; k < reps; k++) { 1096 num = os::random(); 1097 double u = (double)num / m; 1098 assert(u >= 0.0 && u <= 1.0, "bad random number!"); 1099 1100 // calculate mean and variance of the random sequence 1101 mean += u; 1102 variance += (u*u); 1103 } 1104 mean /= reps; 1105 variance /= (reps - 1); 1106 1107 assert(num == 1043618065, "bad seed"); 1108 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); 1109 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); 1110 const double eps = 0.0001; 1111 t = fabsd(mean - 0.5018); 1112 assert(t < eps, "bad mean"); 1113 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; 1114 assert(t < eps, "bad variance"); 1115} 1116#endif 1117 1118 1119// Set up the boot classpath. 1120 1121char* os::format_boot_path(const char* format_string, 1122 const char* home, 1123 int home_len, 1124 char fileSep, 1125 char pathSep) { 1126 assert((fileSep == '/' && pathSep == ':') || 1127 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars"); 1128 1129 // Scan the format string to determine the length of the actual 1130 // boot classpath, and handle platform dependencies as well. 1131 int formatted_path_len = 0; 1132 const char* p; 1133 for (p = format_string; *p != 0; ++p) { 1134 if (*p == '%') formatted_path_len += home_len - 1; 1135 ++formatted_path_len; 1136 } 1137 1138 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal); 1139 if (formatted_path == NULL) { 1140 return NULL; 1141 } 1142 1143 // Create boot classpath from format, substituting separator chars and 1144 // java home directory. 1145 char* q = formatted_path; 1146 for (p = format_string; *p != 0; ++p) { 1147 switch (*p) { 1148 case '%': 1149 strcpy(q, home); 1150 q += home_len; 1151 break; 1152 case '/': 1153 *q++ = fileSep; 1154 break; 1155 case ':': 1156 *q++ = pathSep; 1157 break; 1158 default: 1159 *q++ = *p; 1160 } 1161 } 1162 *q = '\0'; 1163 1164 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); 1165 return formatted_path; 1166} 1167 1168// returns a PATH of all entries in the given directory that do not start with a '.' 1169static char* expand_entries_to_path(char* directory, char fileSep, char pathSep) { 1170 DIR* dir = os::opendir(directory); 1171 if (dir == NULL) return NULL; 1172 1173 char* path = NULL; 1174 size_t path_len = 0; // path length including \0 terminator 1175 1176 size_t directory_len = strlen(directory); 1177 struct dirent *entry; 1178 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal); 1179 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) { 1180 const char* name = entry->d_name; 1181 if (name[0] == '.') continue; 1182 1183 size_t name_len = strlen(name); 1184 size_t needed = directory_len + name_len + 2; 1185 size_t new_len = path_len + needed; 1186 if (path == NULL) { 1187 path = NEW_C_HEAP_ARRAY(char, new_len, mtInternal); 1188 } else { 1189 path = REALLOC_C_HEAP_ARRAY(char, path, new_len, mtInternal); 1190 } 1191 if (path == NULL) 1192 break; 1193 1194 // append <pathSep>directory<fileSep>name 1195 char* p = path; 1196 if (path_len > 0) { 1197 p += (path_len -1); 1198 *p = pathSep; 1199 p++; 1200 } 1201 1202 strcpy(p, directory); 1203 p += directory_len; 1204 1205 *p = fileSep; 1206 p++; 1207 1208 strcpy(p, name); 1209 p += name_len; 1210 1211 path_len = new_len; 1212 } 1213 1214 FREE_C_HEAP_ARRAY(char, dbuf); 1215 os::closedir(dir); 1216 1217 return path; 1218} 1219 1220bool os::set_boot_path(char fileSep, char pathSep) { 1221 const char* home = Arguments::get_java_home(); 1222 int home_len = (int)strlen(home); 1223 1224 static const char* meta_index_dir_format = "%/lib/"; 1225 static const char* meta_index_format = "%/lib/meta-index"; 1226 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); 1227 if (meta_index == NULL) return false; 1228 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); 1229 if (meta_index_dir == NULL) return false; 1230 Arguments::set_meta_index_path(meta_index, meta_index_dir); 1231 1232 char* sysclasspath = NULL; 1233 1234 // images build if rt.jar exists 1235 char* rt_jar = format_boot_path("%/lib/rt.jar", home, home_len, fileSep, pathSep); 1236 if (rt_jar == NULL) return false; 1237 struct stat st; 1238 bool has_rt_jar = (os::stat(rt_jar, &st) == 0); 1239 FREE_C_HEAP_ARRAY(char, rt_jar); 1240 1241 if (has_rt_jar) { 1242 // Any modification to the JAR-file list, for the boot classpath must be 1243 // aligned with install/install/make/common/Pack.gmk. Note: boot class 1244 // path class JARs, are stripped for StackMapTable to reduce download size. 1245 static const char classpath_format[] = 1246 "%/lib/resources.jar:" 1247 "%/lib/rt.jar:" 1248 "%/lib/jsse.jar:" 1249 "%/lib/jce.jar:" 1250 "%/lib/charsets.jar:" 1251 "%/lib/jfr.jar:" 1252 "%/classes"; 1253 sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); 1254 } else { 1255 // no rt.jar, check if developer build with exploded modules 1256 char* modules_dir = format_boot_path("%/modules", home, home_len, fileSep, pathSep); 1257 if (os::stat(modules_dir, &st) == 0) { 1258 if ((st.st_mode & S_IFDIR) == S_IFDIR) { 1259 sysclasspath = expand_entries_to_path(modules_dir, fileSep, pathSep); 1260 } 1261 } 1262 1263 // fallback to classes 1264 if (sysclasspath == NULL) 1265 sysclasspath = format_boot_path("%/classes", home, home_len, fileSep, pathSep); 1266 } 1267 1268 if (sysclasspath == NULL) return false; 1269 Arguments::set_sysclasspath(sysclasspath); 1270 1271 return true; 1272} 1273 1274/* 1275 * Splits a path, based on its separator, the number of 1276 * elements is returned back in n. 1277 * It is the callers responsibility to: 1278 * a> check the value of n, and n may be 0. 1279 * b> ignore any empty path elements 1280 * c> free up the data. 1281 */ 1282char** os::split_path(const char* path, int* n) { 1283 *n = 0; 1284 if (path == NULL || strlen(path) == 0) { 1285 return NULL; 1286 } 1287 const char psepchar = *os::path_separator(); 1288 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal); 1289 if (inpath == NULL) { 1290 return NULL; 1291 } 1292 strcpy(inpath, path); 1293 int count = 1; 1294 char* p = strchr(inpath, psepchar); 1295 // Get a count of elements to allocate memory 1296 while (p != NULL) { 1297 count++; 1298 p++; 1299 p = strchr(p, psepchar); 1300 } 1301 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal); 1302 if (opath == NULL) { 1303 return NULL; 1304 } 1305 1306 // do the actual splitting 1307 p = inpath; 1308 for (int i = 0 ; i < count ; i++) { 1309 size_t len = strcspn(p, os::path_separator()); 1310 if (len > JVM_MAXPATHLEN) { 1311 return NULL; 1312 } 1313 // allocate the string and add terminator storage 1314 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 1315 if (s == NULL) { 1316 return NULL; 1317 } 1318 strncpy(s, p, len); 1319 s[len] = '\0'; 1320 opath[i] = s; 1321 p += len + 1; 1322 } 1323 FREE_C_HEAP_ARRAY(char, inpath); 1324 *n = count; 1325 return opath; 1326} 1327 1328void os::set_memory_serialize_page(address page) { 1329 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); 1330 _mem_serialize_page = (volatile int32_t *)page; 1331 // We initialize the serialization page shift count here 1332 // We assume a cache line size of 64 bytes 1333 assert(SerializePageShiftCount == count, 1334 "thread size changed, fix SerializePageShiftCount constant"); 1335 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); 1336} 1337 1338static volatile intptr_t SerializePageLock = 0; 1339 1340// This method is called from signal handler when SIGSEGV occurs while the current 1341// thread tries to store to the "read-only" memory serialize page during state 1342// transition. 1343void os::block_on_serialize_page_trap() { 1344 if (TraceSafepoint) { 1345 tty->print_cr("Block until the serialize page permission restored"); 1346 } 1347 // When VMThread is holding the SerializePageLock during modifying the 1348 // access permission of the memory serialize page, the following call 1349 // will block until the permission of that page is restored to rw. 1350 // Generally, it is unsafe to manipulate locks in signal handlers, but in 1351 // this case, it's OK as the signal is synchronous and we know precisely when 1352 // it can occur. 1353 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); 1354 Thread::muxRelease(&SerializePageLock); 1355} 1356 1357// Serialize all thread state variables 1358void os::serialize_thread_states() { 1359 // On some platforms such as Solaris & Linux, the time duration of the page 1360 // permission restoration is observed to be much longer than expected due to 1361 // scheduler starvation problem etc. To avoid the long synchronization 1362 // time and expensive page trap spinning, 'SerializePageLock' is used to block 1363 // the mutator thread if such case is encountered. See bug 6546278 for details. 1364 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); 1365 os::protect_memory((char *)os::get_memory_serialize_page(), 1366 os::vm_page_size(), MEM_PROT_READ); 1367 os::protect_memory((char *)os::get_memory_serialize_page(), 1368 os::vm_page_size(), MEM_PROT_RW); 1369 Thread::muxRelease(&SerializePageLock); 1370} 1371 1372// Returns true if the current stack pointer is above the stack shadow 1373// pages, false otherwise. 1374 1375bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { 1376 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); 1377 address sp = current_stack_pointer(); 1378 // Check if we have StackShadowPages above the yellow zone. This parameter 1379 // is dependent on the depth of the maximum VM call stack possible from 1380 // the handler for stack overflow. 'instanceof' in the stack overflow 1381 // handler or a println uses at least 8k stack of VM and native code 1382 // respectively. 1383 const int framesize_in_bytes = 1384 Interpreter::size_top_interpreter_activation(method()) * wordSize; 1385 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) 1386 * vm_page_size()) + framesize_in_bytes; 1387 // The very lower end of the stack 1388 address stack_limit = thread->stack_base() - thread->stack_size(); 1389 return (sp > (stack_limit + reserved_area)); 1390} 1391 1392size_t os::page_size_for_region(size_t region_size, size_t min_pages) { 1393 assert(min_pages > 0, "sanity"); 1394 if (UseLargePages) { 1395 const size_t max_page_size = region_size / min_pages; 1396 1397 for (size_t i = 0; _page_sizes[i] != 0; ++i) { 1398 const size_t page_size = _page_sizes[i]; 1399 if (page_size <= max_page_size && is_size_aligned(region_size, page_size)) { 1400 return page_size; 1401 } 1402 } 1403 } 1404 1405 return vm_page_size(); 1406} 1407 1408#ifndef PRODUCT 1409void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) 1410{ 1411 if (TracePageSizes) { 1412 tty->print("%s: ", str); 1413 for (int i = 0; i < count; ++i) { 1414 tty->print(" " SIZE_FORMAT, page_sizes[i]); 1415 } 1416 tty->cr(); 1417 } 1418} 1419 1420void os::trace_page_sizes(const char* str, const size_t region_min_size, 1421 const size_t region_max_size, const size_t page_size, 1422 const char* base, const size_t size) 1423{ 1424 if (TracePageSizes) { 1425 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT 1426 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT 1427 " size=" SIZE_FORMAT, 1428 str, region_min_size, region_max_size, 1429 page_size, base, size); 1430 } 1431} 1432#endif // #ifndef PRODUCT 1433 1434// This is the working definition of a server class machine: 1435// >= 2 physical CPU's and >=2GB of memory, with some fuzz 1436// because the graphics memory (?) sometimes masks physical memory. 1437// If you want to change the definition of a server class machine 1438// on some OS or platform, e.g., >=4GB on Windows platforms, 1439// then you'll have to parameterize this method based on that state, 1440// as was done for logical processors here, or replicate and 1441// specialize this method for each platform. (Or fix os to have 1442// some inheritance structure and use subclassing. Sigh.) 1443// If you want some platform to always or never behave as a server 1444// class machine, change the setting of AlwaysActAsServerClassMachine 1445// and NeverActAsServerClassMachine in globals*.hpp. 1446bool os::is_server_class_machine() { 1447 // First check for the early returns 1448 if (NeverActAsServerClassMachine) { 1449 return false; 1450 } 1451 if (AlwaysActAsServerClassMachine) { 1452 return true; 1453 } 1454 // Then actually look at the machine 1455 bool result = false; 1456 const unsigned int server_processors = 2; 1457 const julong server_memory = 2UL * G; 1458 // We seem not to get our full complement of memory. 1459 // We allow some part (1/8?) of the memory to be "missing", 1460 // based on the sizes of DIMMs, and maybe graphics cards. 1461 const julong missing_memory = 256UL * M; 1462 1463 /* Is this a server class machine? */ 1464 if ((os::active_processor_count() >= (int)server_processors) && 1465 (os::physical_memory() >= (server_memory - missing_memory))) { 1466 const unsigned int logical_processors = 1467 VM_Version::logical_processors_per_package(); 1468 if (logical_processors > 1) { 1469 const unsigned int physical_packages = 1470 os::active_processor_count() / logical_processors; 1471 if (physical_packages > server_processors) { 1472 result = true; 1473 } 1474 } else { 1475 result = true; 1476 } 1477 } 1478 return result; 1479} 1480 1481void os::SuspendedThreadTask::run() { 1482 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this"); 1483 internal_do_task(); 1484 _done = true; 1485} 1486 1487bool os::create_stack_guard_pages(char* addr, size_t bytes) { 1488 return os::pd_create_stack_guard_pages(addr, bytes); 1489} 1490 1491char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) { 1492 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1493 if (result != NULL) { 1494 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1495 } 1496 1497 return result; 1498} 1499 1500char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, 1501 MEMFLAGS flags) { 1502 char* result = pd_reserve_memory(bytes, addr, alignment_hint); 1503 if (result != NULL) { 1504 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1505 MemTracker::record_virtual_memory_type((address)result, flags); 1506 } 1507 1508 return result; 1509} 1510 1511char* os::attempt_reserve_memory_at(size_t bytes, char* addr) { 1512 char* result = pd_attempt_reserve_memory_at(bytes, addr); 1513 if (result != NULL) { 1514 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC); 1515 } 1516 return result; 1517} 1518 1519void os::split_reserved_memory(char *base, size_t size, 1520 size_t split, bool realloc) { 1521 pd_split_reserved_memory(base, size, split, realloc); 1522} 1523 1524bool os::commit_memory(char* addr, size_t bytes, bool executable) { 1525 bool res = pd_commit_memory(addr, bytes, executable); 1526 if (res) { 1527 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1528 } 1529 return res; 1530} 1531 1532bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 1533 bool executable) { 1534 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable); 1535 if (res) { 1536 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1537 } 1538 return res; 1539} 1540 1541void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable, 1542 const char* mesg) { 1543 pd_commit_memory_or_exit(addr, bytes, executable, mesg); 1544 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC); 1545} 1546 1547void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, 1548 bool executable, const char* mesg) { 1549 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg); 1550 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC); 1551} 1552 1553bool os::uncommit_memory(char* addr, size_t bytes) { 1554 bool res; 1555 if (MemTracker::tracking_level() > NMT_minimal) { 1556 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker(); 1557 res = pd_uncommit_memory(addr, bytes); 1558 if (res) { 1559 tkr.record((address)addr, bytes); 1560 } 1561 } else { 1562 res = pd_uncommit_memory(addr, bytes); 1563 } 1564 return res; 1565} 1566 1567bool os::release_memory(char* addr, size_t bytes) { 1568 bool res; 1569 if (MemTracker::tracking_level() > NMT_minimal) { 1570 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1571 res = pd_release_memory(addr, bytes); 1572 if (res) { 1573 tkr.record((address)addr, bytes); 1574 } 1575 } else { 1576 res = pd_release_memory(addr, bytes); 1577 } 1578 return res; 1579} 1580 1581 1582char* os::map_memory(int fd, const char* file_name, size_t file_offset, 1583 char *addr, size_t bytes, bool read_only, 1584 bool allow_exec) { 1585 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); 1586 if (result != NULL) { 1587 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC); 1588 } 1589 return result; 1590} 1591 1592char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 1593 char *addr, size_t bytes, bool read_only, 1594 bool allow_exec) { 1595 return pd_remap_memory(fd, file_name, file_offset, addr, bytes, 1596 read_only, allow_exec); 1597} 1598 1599bool os::unmap_memory(char *addr, size_t bytes) { 1600 bool result; 1601 if (MemTracker::tracking_level() > NMT_minimal) { 1602 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 1603 result = pd_unmap_memory(addr, bytes); 1604 if (result) { 1605 tkr.record((address)addr, bytes); 1606 } 1607 } else { 1608 result = pd_unmap_memory(addr, bytes); 1609 } 1610 return result; 1611} 1612 1613void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1614 pd_free_memory(addr, bytes, alignment_hint); 1615} 1616 1617void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1618 pd_realign_memory(addr, bytes, alignment_hint); 1619} 1620 1621#ifndef TARGET_OS_FAMILY_windows 1622/* try to switch state from state "from" to state "to" 1623 * returns the state set after the method is complete 1624 */ 1625os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from, 1626 os::SuspendResume::State to) 1627{ 1628 os::SuspendResume::State result = 1629 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from); 1630 if (result == from) { 1631 // success 1632 return to; 1633 } 1634 return result; 1635} 1636#endif 1637 1638/////////////// Unit tests /////////////// 1639 1640#ifndef PRODUCT 1641 1642#define assert_eq(a,b) assert(a == b, err_msg(SIZE_FORMAT " != " SIZE_FORMAT, a, b)) 1643 1644class TestOS : AllStatic { 1645 static size_t small_page_size() { 1646 return os::vm_page_size(); 1647 } 1648 1649 static size_t large_page_size() { 1650 const size_t large_page_size_example = 4 * M; 1651 return os::page_size_for_region(large_page_size_example, 1); 1652 } 1653 1654 static void test_page_size_for_region() { 1655 if (UseLargePages) { 1656 const size_t small_page = small_page_size(); 1657 const size_t large_page = large_page_size(); 1658 1659 if (large_page > small_page) { 1660 size_t num_small_pages_in_large = large_page / small_page; 1661 size_t page = os::page_size_for_region(large_page, num_small_pages_in_large); 1662 1663 assert_eq(page, small_page); 1664 } 1665 } 1666 } 1667 1668 static void test_page_size_for_region_alignment() { 1669 if (UseLargePages) { 1670 const size_t small_page = small_page_size(); 1671 const size_t large_page = large_page_size(); 1672 if (large_page > small_page) { 1673 const size_t unaligned_region = large_page + 17; 1674 size_t page = os::page_size_for_region(unaligned_region, 1); 1675 assert_eq(page, small_page); 1676 1677 const size_t num_pages = 5; 1678 const size_t aligned_region = large_page * num_pages; 1679 page = os::page_size_for_region(aligned_region, num_pages); 1680 assert_eq(page, large_page); 1681 } 1682 } 1683 } 1684 1685 public: 1686 static void run_tests() { 1687 test_page_size_for_region(); 1688 test_page_size_for_region_alignment(); 1689 } 1690}; 1691 1692void TestOS_test() { 1693 TestOS::run_tests(); 1694} 1695 1696#endif // PRODUCT 1697