Mercurial > hg > truffle
annotate src/share/vm/runtime/os.cpp @ 477:24fda36852ce
6727377: VM stack guard pages on Windows should PAGE_READWRITE not PAGE_EXECUTE_READWRITE
Summary: Make reguard_stack change access to RW, not execute and use os::protect_memory with the new parameter when change needed to X.
Reviewed-by: acorn, jcoomes
| author | coleenp |
|---|---|
| date | Wed, 10 Dec 2008 15:14:29 -0800 |
| parents | d95b224e9f17 |
| children | 773234c55e8c |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 196 | 2 * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved. |
| 0 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 8 * | |
| 9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
| 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 12 * version 2 for more details (a copy is included in the LICENSE file that | |
| 13 * accompanied this code). | |
| 14 * | |
| 15 * You should have received a copy of the GNU General Public License version | |
| 16 * 2 along with this work; if not, write to the Free Software Foundation, | |
| 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 18 * | |
| 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 # include "incls/_precompiled.incl" | |
| 26 # include "incls/_os.cpp.incl" | |
| 27 | |
| 28 # include <signal.h> | |
| 29 | |
| 30 OSThread* os::_starting_thread = NULL; | |
| 31 address os::_polling_page = NULL; | |
| 32 volatile int32_t* os::_mem_serialize_page = NULL; | |
| 33 uintptr_t os::_serialize_page_mask = 0; | |
| 34 long os::_rand_seed = 1; | |
| 35 int os::_processor_count = 0; | |
| 36 size_t os::_page_sizes[os::page_sizes_max]; | |
| 37 | |
| 38 #ifndef PRODUCT | |
| 39 int os::num_mallocs = 0; // # of calls to malloc/realloc | |
| 40 size_t os::alloc_bytes = 0; // # of bytes allocated | |
| 41 int os::num_frees = 0; // # of calls to free | |
| 42 #endif | |
| 43 | |
| 44 // Fill in buffer with current local time as an ISO-8601 string. | |
| 45 // E.g., yyyy-mm-ddThh:mm:ss-zzzz. | |
| 46 // Returns buffer, or NULL if it failed. | |
| 47 // This would mostly be a call to | |
| 48 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....) | |
| 49 // except that on Windows the %z behaves badly, so we do it ourselves. | |
| 50 // Also, people wanted milliseconds on there, | |
| 51 // and strftime doesn't do milliseconds. | |
| 52 char* os::iso8601_time(char* buffer, size_t buffer_length) { | |
| 53 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0" | |
| 54 // 1 2 | |
| 55 // 12345678901234567890123456789 | |
| 56 static const char* iso8601_format = | |
| 57 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"; | |
| 58 static const size_t needed_buffer = 29; | |
| 59 | |
| 60 // Sanity check the arguments | |
| 61 if (buffer == NULL) { | |
| 62 assert(false, "NULL buffer"); | |
| 63 return NULL; | |
| 64 } | |
| 65 if (buffer_length < needed_buffer) { | |
| 66 assert(false, "buffer_length too small"); | |
| 67 return NULL; | |
| 68 } | |
| 69 // Get the current time | |
| 61 | 70 jlong milliseconds_since_19700101 = javaTimeMillis(); |
| 0 | 71 const int milliseconds_per_microsecond = 1000; |
| 72 const time_t seconds_since_19700101 = | |
| 73 milliseconds_since_19700101 / milliseconds_per_microsecond; | |
| 74 const int milliseconds_after_second = | |
| 75 milliseconds_since_19700101 % milliseconds_per_microsecond; | |
| 76 // Convert the time value to a tm and timezone variable | |
| 77 const struct tm *time_struct_temp = localtime(&seconds_since_19700101); | |
| 78 if (time_struct_temp == NULL) { | |
| 79 assert(false, "Failed localtime"); | |
| 80 return NULL; | |
| 81 } | |
| 82 // Save the results of localtime | |
| 83 const struct tm time_struct = *time_struct_temp; | |
| 84 const time_t zone = timezone; | |
| 85 | |
| 86 // If daylight savings time is in effect, | |
| 87 // we are 1 hour East of our time zone | |
| 88 const time_t seconds_per_minute = 60; | |
| 89 const time_t minutes_per_hour = 60; | |
| 90 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour; | |
| 91 time_t UTC_to_local = zone; | |
| 92 if (time_struct.tm_isdst > 0) { | |
| 93 UTC_to_local = UTC_to_local - seconds_per_hour; | |
| 94 } | |
| 95 // Compute the time zone offset. | |
| 96 // localtime(3C) sets timezone to the difference (in seconds) | |
| 97 // between UTC and and local time. | |
| 98 // ISO 8601 says we need the difference between local time and UTC, | |
| 99 // we change the sign of the localtime(3C) result. | |
| 100 const time_t local_to_UTC = -(UTC_to_local); | |
| 101 // Then we have to figure out if if we are ahead (+) or behind (-) UTC. | |
| 102 char sign_local_to_UTC = '+'; | |
| 103 time_t abs_local_to_UTC = local_to_UTC; | |
| 104 if (local_to_UTC < 0) { | |
| 105 sign_local_to_UTC = '-'; | |
| 106 abs_local_to_UTC = -(abs_local_to_UTC); | |
| 107 } | |
| 108 // Convert time zone offset seconds to hours and minutes. | |
| 109 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour); | |
| 110 const time_t zone_min = | |
| 111 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute); | |
| 112 | |
| 113 // Print an ISO 8601 date and time stamp into the buffer | |
| 114 const int year = 1900 + time_struct.tm_year; | |
| 115 const int month = 1 + time_struct.tm_mon; | |
| 116 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format, | |
| 117 year, | |
| 118 month, | |
| 119 time_struct.tm_mday, | |
| 120 time_struct.tm_hour, | |
| 121 time_struct.tm_min, | |
| 122 time_struct.tm_sec, | |
| 123 milliseconds_after_second, | |
| 124 sign_local_to_UTC, | |
| 125 zone_hours, | |
| 126 zone_min); | |
| 127 if (printed == 0) { | |
| 128 assert(false, "Failed jio_printf"); | |
| 129 return NULL; | |
| 130 } | |
| 131 return buffer; | |
| 132 } | |
| 133 | |
| 134 OSReturn os::set_priority(Thread* thread, ThreadPriority p) { | |
| 135 #ifdef ASSERT | |
| 136 if (!(!thread->is_Java_thread() || | |
| 137 Thread::current() == thread || | |
| 138 Threads_lock->owned_by_self() | |
| 139 || thread->is_Compiler_thread() | |
| 140 )) { | |
| 141 assert(false, "possibility of dangling Thread pointer"); | |
| 142 } | |
| 143 #endif | |
| 144 | |
| 145 if (p >= MinPriority && p <= MaxPriority) { | |
| 146 int priority = java_to_os_priority[p]; | |
| 147 return set_native_priority(thread, priority); | |
| 148 } else { | |
| 149 assert(false, "Should not happen"); | |
| 150 return OS_ERR; | |
| 151 } | |
| 152 } | |
| 153 | |
| 154 | |
| 155 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) { | |
| 156 int p; | |
| 157 int os_prio; | |
| 158 OSReturn ret = get_native_priority(thread, &os_prio); | |
| 159 if (ret != OS_OK) return ret; | |
| 160 | |
| 161 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ; | |
| 162 priority = (ThreadPriority)p; | |
| 163 return OS_OK; | |
| 164 } | |
| 165 | |
| 166 | |
| 167 // --------------------- sun.misc.Signal (optional) --------------------- | |
| 168 | |
| 169 | |
| 170 // SIGBREAK is sent by the keyboard to query the VM state | |
| 171 #ifndef SIGBREAK | |
| 172 #define SIGBREAK SIGQUIT | |
| 173 #endif | |
| 174 | |
| 175 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread. | |
| 176 | |
| 177 | |
| 178 static void signal_thread_entry(JavaThread* thread, TRAPS) { | |
| 179 os::set_priority(thread, NearMaxPriority); | |
| 180 while (true) { | |
| 181 int sig; | |
| 182 { | |
| 183 // FIXME : Currently we have not decieded what should be the status | |
| 184 // for this java thread blocked here. Once we decide about | |
| 185 // that we should fix this. | |
| 186 sig = os::signal_wait(); | |
| 187 } | |
| 188 if (sig == os::sigexitnum_pd()) { | |
| 189 // Terminate the signal thread | |
| 190 return; | |
| 191 } | |
| 192 | |
| 193 switch (sig) { | |
| 194 case SIGBREAK: { | |
| 195 // Check if the signal is a trigger to start the Attach Listener - in that | |
| 196 // case don't print stack traces. | |
| 197 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) { | |
| 198 continue; | |
| 199 } | |
| 200 // Print stack traces | |
| 201 // Any SIGBREAK operations added here should make sure to flush | |
| 202 // the output stream (e.g. tty->flush()) after output. See 4803766. | |
| 203 // Each module also prints an extra carriage return after its output. | |
| 204 VM_PrintThreads op; | |
| 205 VMThread::execute(&op); | |
| 206 VM_PrintJNI jni_op; | |
| 207 VMThread::execute(&jni_op); | |
| 208 VM_FindDeadlocks op1(tty); | |
| 209 VMThread::execute(&op1); | |
| 210 Universe::print_heap_at_SIGBREAK(); | |
| 211 if (PrintClassHistogram) { | |
| 212 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */); | |
| 213 VMThread::execute(&op1); | |
| 214 } | |
| 215 if (JvmtiExport::should_post_data_dump()) { | |
| 216 JvmtiExport::post_data_dump(); | |
| 217 } | |
| 218 break; | |
| 219 } | |
| 220 default: { | |
| 221 // Dispatch the signal to java | |
| 222 HandleMark hm(THREAD); | |
| 223 klassOop k = SystemDictionary::resolve_or_null(vmSymbolHandles::sun_misc_Signal(), THREAD); | |
| 224 KlassHandle klass (THREAD, k); | |
| 225 if (klass.not_null()) { | |
| 226 JavaValue result(T_VOID); | |
| 227 JavaCallArguments args; | |
| 228 args.push_int(sig); | |
| 229 JavaCalls::call_static( | |
| 230 &result, | |
| 231 klass, | |
| 232 vmSymbolHandles::dispatch_name(), | |
| 233 vmSymbolHandles::int_void_signature(), | |
| 234 &args, | |
| 235 THREAD | |
| 236 ); | |
| 237 } | |
| 238 if (HAS_PENDING_EXCEPTION) { | |
| 239 // tty is initialized early so we don't expect it to be null, but | |
| 240 // if it is we can't risk doing an initialization that might | |
| 241 // trigger additional out-of-memory conditions | |
| 242 if (tty != NULL) { | |
| 243 char klass_name[256]; | |
| 244 char tmp_sig_name[16]; | |
| 245 const char* sig_name = "UNKNOWN"; | |
| 246 instanceKlass::cast(PENDING_EXCEPTION->klass())-> | |
| 247 name()->as_klass_external_name(klass_name, 256); | |
| 248 if (os::exception_name(sig, tmp_sig_name, 16) != NULL) | |
| 249 sig_name = tmp_sig_name; | |
| 250 warning("Exception %s occurred dispatching signal %s to handler" | |
| 251 "- the VM may need to be forcibly terminated", | |
| 252 klass_name, sig_name ); | |
| 253 } | |
| 254 CLEAR_PENDING_EXCEPTION; | |
| 255 } | |
| 256 } | |
| 257 } | |
| 258 } | |
| 259 } | |
| 260 | |
| 261 | |
| 262 void os::signal_init() { | |
| 263 if (!ReduceSignalUsage) { | |
| 264 // Setup JavaThread for processing signals | |
| 265 EXCEPTION_MARK; | |
| 266 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_Thread(), true, CHECK); | |
| 267 instanceKlassHandle klass (THREAD, k); | |
| 268 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); | |
| 269 | |
| 270 const char thread_name[] = "Signal Dispatcher"; | |
| 271 Handle string = java_lang_String::create_from_str(thread_name, CHECK); | |
| 272 | |
| 273 // Initialize thread_oop to put it into the system threadGroup | |
| 274 Handle thread_group (THREAD, Universe::system_thread_group()); | |
| 275 JavaValue result(T_VOID); | |
| 276 JavaCalls::call_special(&result, thread_oop, | |
| 277 klass, | |
| 278 vmSymbolHandles::object_initializer_name(), | |
| 279 vmSymbolHandles::threadgroup_string_void_signature(), | |
| 280 thread_group, | |
| 281 string, | |
| 282 CHECK); | |
| 283 | |
| 284 KlassHandle group(THREAD, SystemDictionary::threadGroup_klass()); | |
| 285 JavaCalls::call_special(&result, | |
| 286 thread_group, | |
| 287 group, | |
| 288 vmSymbolHandles::add_method_name(), | |
| 289 vmSymbolHandles::thread_void_signature(), | |
| 290 thread_oop, // ARG 1 | |
| 291 CHECK); | |
| 292 | |
| 293 os::signal_init_pd(); | |
| 294 | |
| 295 { MutexLocker mu(Threads_lock); | |
| 296 JavaThread* signal_thread = new JavaThread(&signal_thread_entry); | |
| 297 | |
| 298 // At this point it may be possible that no osthread was created for the | |
| 299 // JavaThread due to lack of memory. We would have to throw an exception | |
| 300 // in that case. However, since this must work and we do not allow | |
| 301 // exceptions anyway, check and abort if this fails. | |
| 302 if (signal_thread == NULL || signal_thread->osthread() == NULL) { | |
| 303 vm_exit_during_initialization("java.lang.OutOfMemoryError", | |
| 304 "unable to create new native thread"); | |
| 305 } | |
| 306 | |
| 307 java_lang_Thread::set_thread(thread_oop(), signal_thread); | |
| 308 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority); | |
| 309 java_lang_Thread::set_daemon(thread_oop()); | |
| 310 | |
| 311 signal_thread->set_threadObj(thread_oop()); | |
| 312 Threads::add(signal_thread); | |
| 313 Thread::start(signal_thread); | |
| 314 } | |
| 315 // Handle ^BREAK | |
| 316 os::signal(SIGBREAK, os::user_handler()); | |
| 317 } | |
| 318 } | |
| 319 | |
| 320 | |
| 321 void os::terminate_signal_thread() { | |
| 322 if (!ReduceSignalUsage) | |
| 323 signal_notify(sigexitnum_pd()); | |
| 324 } | |
| 325 | |
| 326 | |
| 327 // --------------------- loading libraries --------------------- | |
| 328 | |
| 329 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *); | |
| 330 extern struct JavaVM_ main_vm; | |
| 331 | |
| 332 static void* _native_java_library = NULL; | |
| 333 | |
| 334 void* os::native_java_library() { | |
| 335 if (_native_java_library == NULL) { | |
| 336 char buffer[JVM_MAXPATHLEN]; | |
| 337 char ebuf[1024]; | |
| 338 | |
| 242 | 339 // Try to load verify dll first. In 1.3 java dll depends on it and is not |
| 340 // always able to find it when the loading executable is outside the JDK. | |
| 0 | 341 // In order to keep working with 1.2 we ignore any loading errors. |
| 242 | 342 dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), "verify"); |
| 343 dll_load(buffer, ebuf, sizeof(ebuf)); | |
| 0 | 344 |
| 345 // Load java dll | |
| 242 | 346 dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), "java"); |
| 347 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf)); | |
| 0 | 348 if (_native_java_library == NULL) { |
| 349 vm_exit_during_initialization("Unable to load native library", ebuf); | |
| 350 } | |
| 242 | 351 } |
| 352 static jboolean onLoaded = JNI_FALSE; | |
| 353 if (onLoaded) { | |
| 354 // We may have to wait to fire OnLoad until TLS is initialized. | |
| 355 if (ThreadLocalStorage::is_initialized()) { | |
| 356 // The JNI_OnLoad handling is normally done by method load in | |
| 357 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library | |
| 358 // explicitly so we have to check for JNI_OnLoad as well | |
| 359 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS; | |
| 360 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR( | |
| 361 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0])); | |
| 362 if (JNI_OnLoad != NULL) { | |
| 363 JavaThread* thread = JavaThread::current(); | |
| 364 ThreadToNativeFromVM ttn(thread); | |
| 365 HandleMark hm(thread); | |
| 366 jint ver = (*JNI_OnLoad)(&main_vm, NULL); | |
| 367 onLoaded = JNI_TRUE; | |
| 368 if (!Threads::is_supported_jni_version_including_1_1(ver)) { | |
| 369 vm_exit_during_initialization("Unsupported JNI version"); | |
| 370 } | |
| 0 | 371 } |
| 372 } | |
| 373 } | |
| 374 return _native_java_library; | |
| 375 } | |
| 376 | |
| 377 // --------------------- heap allocation utilities --------------------- | |
| 378 | |
| 379 char *os::strdup(const char *str) { | |
| 380 size_t size = strlen(str); | |
| 381 char *dup_str = (char *)malloc(size + 1); | |
| 382 if (dup_str == NULL) return NULL; | |
| 383 strcpy(dup_str, str); | |
| 384 return dup_str; | |
| 385 } | |
| 386 | |
| 387 | |
| 388 | |
| 389 #ifdef ASSERT | |
| 390 #define space_before (MallocCushion + sizeof(double)) | |
| 391 #define space_after MallocCushion | |
| 392 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t)) | |
| 393 #define size_addr_from_obj(p) ((size_t*)p - 1) | |
| 394 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly | |
| 395 // NB: cannot be debug variable, because these aren't set from the command line until | |
| 396 // *after* the first few allocs already happened | |
| 397 #define MallocCushion 16 | |
| 398 #else | |
| 399 #define space_before 0 | |
| 400 #define space_after 0 | |
| 401 #define size_addr_from_base(p) should not use w/o ASSERT | |
| 402 #define size_addr_from_obj(p) should not use w/o ASSERT | |
| 403 #define MallocCushion 0 | |
| 404 #endif | |
| 405 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */ | |
| 406 | |
| 407 #ifdef ASSERT | |
| 408 inline size_t get_size(void* obj) { | |
| 409 size_t size = *size_addr_from_obj(obj); | |
| 410 if (size < 0 ) | |
| 411 fatal2("free: size field of object #%p was overwritten (%lu)", obj, size); | |
| 412 return size; | |
| 413 } | |
| 414 | |
| 415 u_char* find_cushion_backwards(u_char* start) { | |
| 416 u_char* p = start; | |
| 417 while (p[ 0] != badResourceValue || p[-1] != badResourceValue || | |
| 418 p[-2] != badResourceValue || p[-3] != badResourceValue) p--; | |
| 419 // ok, we have four consecutive marker bytes; find start | |
| 420 u_char* q = p - 4; | |
| 421 while (*q == badResourceValue) q--; | |
| 422 return q + 1; | |
| 423 } | |
| 424 | |
| 425 u_char* find_cushion_forwards(u_char* start) { | |
| 426 u_char* p = start; | |
| 427 while (p[0] != badResourceValue || p[1] != badResourceValue || | |
| 428 p[2] != badResourceValue || p[3] != badResourceValue) p++; | |
| 429 // ok, we have four consecutive marker bytes; find end of cushion | |
| 430 u_char* q = p + 4; | |
| 431 while (*q == badResourceValue) q++; | |
| 432 return q - MallocCushion; | |
| 433 } | |
| 434 | |
| 435 void print_neighbor_blocks(void* ptr) { | |
| 436 // find block allocated before ptr (not entirely crash-proof) | |
| 437 if (MallocCushion < 4) { | |
| 438 tty->print_cr("### cannot find previous block (MallocCushion < 4)"); | |
| 439 return; | |
| 440 } | |
| 441 u_char* start_of_this_block = (u_char*)ptr - space_before; | |
| 442 u_char* end_of_prev_block_data = start_of_this_block - space_after -1; | |
| 443 // look for cushion in front of prev. block | |
| 444 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data); | |
| 445 ptrdiff_t size = *size_addr_from_base(start_of_prev_block); | |
| 446 u_char* obj = start_of_prev_block + space_before; | |
| 447 if (size <= 0 ) { | |
| 448 // start is bad; mayhave been confused by OS data inbetween objects | |
| 449 // search one more backwards | |
| 450 start_of_prev_block = find_cushion_backwards(start_of_prev_block); | |
| 451 size = *size_addr_from_base(start_of_prev_block); | |
| 452 obj = start_of_prev_block + space_before; | |
| 453 } | |
| 454 | |
| 455 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) { | |
| 456 tty->print_cr("### previous object: %p (%ld bytes)", obj, size); | |
| 457 } else { | |
| 458 tty->print_cr("### previous object (not sure if correct): %p (%ld bytes)", obj, size); | |
| 459 } | |
| 460 | |
| 461 // now find successor block | |
| 462 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after; | |
| 463 start_of_next_block = find_cushion_forwards(start_of_next_block); | |
| 464 u_char* next_obj = start_of_next_block + space_before; | |
| 465 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block); | |
| 466 if (start_of_next_block[0] == badResourceValue && | |
| 467 start_of_next_block[1] == badResourceValue && | |
| 468 start_of_next_block[2] == badResourceValue && | |
| 469 start_of_next_block[3] == badResourceValue) { | |
| 470 tty->print_cr("### next object: %p (%ld bytes)", next_obj, next_size); | |
| 471 } else { | |
| 472 tty->print_cr("### next object (not sure if correct): %p (%ld bytes)", next_obj, next_size); | |
| 473 } | |
| 474 } | |
| 475 | |
| 476 | |
| 477 void report_heap_error(void* memblock, void* bad, const char* where) { | |
| 478 tty->print_cr("## nof_mallocs = %d, nof_frees = %d", os::num_mallocs, os::num_frees); | |
| 479 tty->print_cr("## memory stomp: byte at %p %s object %p", bad, where, memblock); | |
| 480 print_neighbor_blocks(memblock); | |
| 481 fatal("memory stomping error"); | |
| 482 } | |
| 483 | |
| 484 void verify_block(void* memblock) { | |
| 485 size_t size = get_size(memblock); | |
| 486 if (MallocCushion) { | |
| 487 u_char* ptr = (u_char*)memblock - space_before; | |
| 488 for (int i = 0; i < MallocCushion; i++) { | |
| 489 if (ptr[i] != badResourceValue) { | |
| 490 report_heap_error(memblock, ptr+i, "in front of"); | |
| 491 } | |
| 492 } | |
| 493 u_char* end = (u_char*)memblock + size + space_after; | |
| 494 for (int j = -MallocCushion; j < 0; j++) { | |
| 495 if (end[j] != badResourceValue) { | |
| 496 report_heap_error(memblock, end+j, "after"); | |
| 497 } | |
| 498 } | |
| 499 } | |
| 500 } | |
| 501 #endif | |
| 502 | |
| 503 void* os::malloc(size_t size) { | |
| 504 NOT_PRODUCT(num_mallocs++); | |
| 505 NOT_PRODUCT(alloc_bytes += size); | |
| 506 | |
| 507 if (size == 0) { | |
| 508 // return a valid pointer if size is zero | |
| 509 // if NULL is returned the calling functions assume out of memory. | |
| 510 size = 1; | |
| 511 } | |
| 512 | |
| 513 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); | |
| 514 u_char* ptr = (u_char*)::malloc(size + space_before + space_after); | |
| 515 #ifdef ASSERT | |
| 516 if (ptr == NULL) return NULL; | |
| 517 if (MallocCushion) { | |
| 518 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue; | |
| 519 u_char* end = ptr + space_before + size; | |
| 520 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad; | |
| 521 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue; | |
| 522 } | |
| 523 // put size just before data | |
| 524 *size_addr_from_base(ptr) = size; | |
| 525 #endif | |
| 526 u_char* memblock = ptr + space_before; | |
| 527 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { | |
| 528 tty->print_cr("os::malloc caught, %lu bytes --> %p", size, memblock); | |
| 529 breakpoint(); | |
| 530 } | |
| 531 debug_only(if (paranoid) verify_block(memblock)); | |
| 532 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc %lu bytes --> %p", size, memblock); | |
| 533 return memblock; | |
| 534 } | |
| 535 | |
| 536 | |
| 537 void* os::realloc(void *memblock, size_t size) { | |
| 538 NOT_PRODUCT(num_mallocs++); | |
| 539 NOT_PRODUCT(alloc_bytes += size); | |
| 540 #ifndef ASSERT | |
| 541 return ::realloc(memblock, size); | |
| 542 #else | |
| 543 if (memblock == NULL) { | |
| 544 return os::malloc(size); | |
| 545 } | |
| 546 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { | |
| 547 tty->print_cr("os::realloc caught %p", memblock); | |
| 548 breakpoint(); | |
| 549 } | |
| 550 verify_block(memblock); | |
| 551 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); | |
| 552 if (size == 0) return NULL; | |
| 553 // always move the block | |
| 554 void* ptr = malloc(size); | |
| 555 if (PrintMalloc) tty->print_cr("os::remalloc %lu bytes, %p --> %p", size, memblock, ptr); | |
| 556 // Copy to new memory if malloc didn't fail | |
| 557 if ( ptr != NULL ) { | |
| 558 memcpy(ptr, memblock, MIN2(size, get_size(memblock))); | |
| 559 if (paranoid) verify_block(ptr); | |
| 560 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) { | |
| 561 tty->print_cr("os::realloc caught, %lu bytes --> %p", size, ptr); | |
| 562 breakpoint(); | |
| 563 } | |
| 564 free(memblock); | |
| 565 } | |
| 566 return ptr; | |
| 567 #endif | |
| 568 } | |
| 569 | |
| 570 | |
| 571 void os::free(void *memblock) { | |
| 572 NOT_PRODUCT(num_frees++); | |
| 573 #ifdef ASSERT | |
| 574 if (memblock == NULL) return; | |
| 575 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { | |
| 576 if (tty != NULL) tty->print_cr("os::free caught %p", memblock); | |
| 577 breakpoint(); | |
| 578 } | |
| 579 verify_block(memblock); | |
| 580 if (PrintMalloc && tty != NULL) | |
| 581 // tty->print_cr("os::free %p", memblock); | |
| 582 fprintf(stderr, "os::free %p\n", memblock); | |
| 583 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); | |
| 584 // Added by detlefs. | |
| 585 if (MallocCushion) { | |
| 586 u_char* ptr = (u_char*)memblock - space_before; | |
| 587 for (u_char* p = ptr; p < ptr + MallocCushion; p++) { | |
| 588 guarantee(*p == badResourceValue, | |
| 589 "Thing freed should be malloc result."); | |
| 590 *p = (u_char)freeBlockPad; | |
| 591 } | |
| 592 size_t size = get_size(memblock); | |
| 593 u_char* end = ptr + space_before + size; | |
| 594 for (u_char* q = end; q < end + MallocCushion; q++) { | |
| 595 guarantee(*q == badResourceValue, | |
| 596 "Thing freed should be malloc result."); | |
| 597 *q = (u_char)freeBlockPad; | |
| 598 } | |
| 599 } | |
| 600 #endif | |
| 601 ::free((char*)memblock - space_before); | |
| 602 } | |
| 603 | |
| 604 void os::init_random(long initval) { | |
| 605 _rand_seed = initval; | |
| 606 } | |
| 607 | |
| 608 | |
| 609 long os::random() { | |
| 610 /* standard, well-known linear congruential random generator with | |
| 611 * next_rand = (16807*seed) mod (2**31-1) | |
| 612 * see | |
| 613 * (1) "Random Number Generators: Good Ones Are Hard to Find", | |
| 614 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988), | |
| 615 * (2) "Two Fast Implementations of the 'Minimal Standard' Random | |
| 616 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88. | |
| 617 */ | |
| 618 const long a = 16807; | |
| 619 const unsigned long m = 2147483647; | |
| 620 const long q = m / a; assert(q == 127773, "weird math"); | |
| 621 const long r = m % a; assert(r == 2836, "weird math"); | |
| 622 | |
| 623 // compute az=2^31p+q | |
| 624 unsigned long lo = a * (long)(_rand_seed & 0xFFFF); | |
| 625 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16); | |
| 626 lo += (hi & 0x7FFF) << 16; | |
| 627 | |
| 628 // if q overflowed, ignore the overflow and increment q | |
| 629 if (lo > m) { | |
| 630 lo &= m; | |
| 631 ++lo; | |
| 632 } | |
| 633 lo += hi >> 15; | |
| 634 | |
| 635 // if (p+q) overflowed, ignore the overflow and increment (p+q) | |
| 636 if (lo > m) { | |
| 637 lo &= m; | |
| 638 ++lo; | |
| 639 } | |
| 640 return (_rand_seed = lo); | |
| 641 } | |
| 642 | |
| 643 // The INITIALIZED state is distinguished from the SUSPENDED state because the | |
| 644 // conditions in which a thread is first started are different from those in which | |
| 645 // a suspension is resumed. These differences make it hard for us to apply the | |
| 646 // tougher checks when starting threads that we want to do when resuming them. | |
| 647 // However, when start_thread is called as a result of Thread.start, on a Java | |
| 648 // thread, the operation is synchronized on the Java Thread object. So there | |
| 649 // cannot be a race to start the thread and hence for the thread to exit while | |
| 650 // we are working on it. Non-Java threads that start Java threads either have | |
| 651 // to do so in a context in which races are impossible, or should do appropriate | |
| 652 // locking. | |
| 653 | |
| 654 void os::start_thread(Thread* thread) { | |
| 655 // guard suspend/resume | |
| 656 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag); | |
| 657 OSThread* osthread = thread->osthread(); | |
| 658 osthread->set_state(RUNNABLE); | |
| 659 pd_start_thread(thread); | |
| 660 } | |
| 661 | |
| 662 //--------------------------------------------------------------------------- | |
| 663 // Helper functions for fatal error handler | |
| 664 | |
| 665 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) { | |
| 666 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking"); | |
| 667 | |
| 668 int cols = 0; | |
| 669 int cols_per_line = 0; | |
| 670 switch (unitsize) { | |
| 671 case 1: cols_per_line = 16; break; | |
| 672 case 2: cols_per_line = 8; break; | |
| 673 case 4: cols_per_line = 4; break; | |
| 674 case 8: cols_per_line = 2; break; | |
| 675 default: return; | |
| 676 } | |
| 677 | |
| 678 address p = start; | |
| 679 st->print(PTR_FORMAT ": ", start); | |
| 680 while (p < end) { | |
| 681 switch (unitsize) { | |
| 682 case 1: st->print("%02x", *(u1*)p); break; | |
| 683 case 2: st->print("%04x", *(u2*)p); break; | |
| 684 case 4: st->print("%08x", *(u4*)p); break; | |
| 685 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break; | |
| 686 } | |
| 687 p += unitsize; | |
| 688 cols++; | |
| 689 if (cols >= cols_per_line && p < end) { | |
| 690 cols = 0; | |
| 691 st->cr(); | |
| 692 st->print(PTR_FORMAT ": ", p); | |
| 693 } else { | |
| 694 st->print(" "); | |
| 695 } | |
| 696 } | |
| 697 st->cr(); | |
| 698 } | |
| 699 | |
| 700 void os::print_environment_variables(outputStream* st, const char** env_list, | |
| 701 char* buffer, int len) { | |
| 702 if (env_list) { | |
| 703 st->print_cr("Environment Variables:"); | |
| 704 | |
| 705 for (int i = 0; env_list[i] != NULL; i++) { | |
| 706 if (getenv(env_list[i], buffer, len)) { | |
| 707 st->print(env_list[i]); | |
| 708 st->print("="); | |
| 709 st->print_cr(buffer); | |
| 710 } | |
| 711 } | |
| 712 } | |
| 713 } | |
| 714 | |
| 715 void os::print_cpu_info(outputStream* st) { | |
| 716 // cpu | |
| 717 st->print("CPU:"); | |
| 718 st->print("total %d", os::processor_count()); | |
| 719 // It's not safe to query number of active processors after crash | |
| 720 // st->print("(active %d)", os::active_processor_count()); | |
| 721 st->print(" %s", VM_Version::cpu_features()); | |
| 722 st->cr(); | |
| 723 } | |
| 724 | |
| 725 void os::print_date_and_time(outputStream *st) { | |
| 726 time_t tloc; | |
| 727 (void)time(&tloc); | |
| 728 st->print("time: %s", ctime(&tloc)); // ctime adds newline. | |
| 729 | |
| 730 double t = os::elapsedTime(); | |
| 731 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in | |
| 732 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int | |
| 733 // before printf. We lost some precision, but who cares? | |
| 734 st->print_cr("elapsed time: %d seconds", (int)t); | |
| 735 } | |
| 736 | |
| 737 | |
| 738 // Looks like all platforms except IA64 can use the same function to check | |
| 739 // if C stack is walkable beyond current frame. The check for fp() is not | |
| 740 // necessary on Sparc, but it's harmless. | |
| 741 bool os::is_first_C_frame(frame* fr) { | |
| 742 #ifdef IA64 | |
| 743 // In order to walk native frames on Itanium, we need to access the unwind | |
| 744 // table, which is inside ELF. We don't want to parse ELF after fatal error, | |
| 745 // so return true for IA64. If we need to support C stack walking on IA64, | |
| 746 // this function needs to be moved to CPU specific files, as fp() on IA64 | |
| 747 // is register stack, which grows towards higher memory address. | |
| 748 return true; | |
| 749 #endif | |
| 750 | |
| 751 // Load up sp, fp, sender sp and sender fp, check for reasonable values. | |
| 752 // Check usp first, because if that's bad the other accessors may fault | |
| 753 // on some architectures. Ditto ufp second, etc. | |
| 754 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1); | |
| 755 // sp on amd can be 32 bit aligned. | |
| 756 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1); | |
| 757 | |
| 758 uintptr_t usp = (uintptr_t)fr->sp(); | |
| 759 if ((usp & sp_align_mask) != 0) return true; | |
| 760 | |
| 761 uintptr_t ufp = (uintptr_t)fr->fp(); | |
| 762 if ((ufp & fp_align_mask) != 0) return true; | |
| 763 | |
| 764 uintptr_t old_sp = (uintptr_t)fr->sender_sp(); | |
| 765 if ((old_sp & sp_align_mask) != 0) return true; | |
| 766 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true; | |
| 767 | |
| 768 uintptr_t old_fp = (uintptr_t)fr->link(); | |
| 769 if ((old_fp & fp_align_mask) != 0) return true; | |
| 770 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true; | |
| 771 | |
| 772 // stack grows downwards; if old_fp is below current fp or if the stack | |
| 773 // frame is too large, either the stack is corrupted or fp is not saved | |
| 774 // on stack (i.e. on x86, ebp may be used as general register). The stack | |
| 775 // is not walkable beyond current frame. | |
| 776 if (old_fp < ufp) return true; | |
| 777 if (old_fp - ufp > 64 * K) return true; | |
| 778 | |
| 779 return false; | |
| 780 } | |
| 781 | |
| 782 #ifdef ASSERT | |
| 783 extern "C" void test_random() { | |
| 784 const double m = 2147483647; | |
| 785 double mean = 0.0, variance = 0.0, t; | |
| 786 long reps = 10000; | |
| 787 unsigned long seed = 1; | |
| 788 | |
| 789 tty->print_cr("seed %ld for %ld repeats...", seed, reps); | |
| 790 os::init_random(seed); | |
| 791 long num; | |
| 792 for (int k = 0; k < reps; k++) { | |
| 793 num = os::random(); | |
| 794 double u = (double)num / m; | |
| 795 assert(u >= 0.0 && u <= 1.0, "bad random number!"); | |
| 796 | |
| 797 // calculate mean and variance of the random sequence | |
| 798 mean += u; | |
| 799 variance += (u*u); | |
| 800 } | |
| 801 mean /= reps; | |
| 802 variance /= (reps - 1); | |
| 803 | |
| 804 assert(num == 1043618065, "bad seed"); | |
| 805 tty->print_cr("mean of the 1st 10000 numbers: %f", mean); | |
| 806 tty->print_cr("variance of the 1st 10000 numbers: %f", variance); | |
| 807 const double eps = 0.0001; | |
| 808 t = fabsd(mean - 0.5018); | |
| 809 assert(t < eps, "bad mean"); | |
| 810 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355; | |
| 811 assert(t < eps, "bad variance"); | |
| 812 } | |
| 813 #endif | |
| 814 | |
| 815 | |
| 816 // Set up the boot classpath. | |
| 817 | |
| 818 char* os::format_boot_path(const char* format_string, | |
| 819 const char* home, | |
| 820 int home_len, | |
| 821 char fileSep, | |
| 822 char pathSep) { | |
| 823 assert((fileSep == '/' && pathSep == ':') || | |
| 824 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars"); | |
| 825 | |
| 826 // Scan the format string to determine the length of the actual | |
| 827 // boot classpath, and handle platform dependencies as well. | |
| 828 int formatted_path_len = 0; | |
| 829 const char* p; | |
| 830 for (p = format_string; *p != 0; ++p) { | |
| 831 if (*p == '%') formatted_path_len += home_len - 1; | |
| 832 ++formatted_path_len; | |
| 833 } | |
| 834 | |
| 835 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1); | |
| 836 if (formatted_path == NULL) { | |
| 837 return NULL; | |
| 838 } | |
| 839 | |
| 840 // Create boot classpath from format, substituting separator chars and | |
| 841 // java home directory. | |
| 842 char* q = formatted_path; | |
| 843 for (p = format_string; *p != 0; ++p) { | |
| 844 switch (*p) { | |
| 845 case '%': | |
| 846 strcpy(q, home); | |
| 847 q += home_len; | |
| 848 break; | |
| 849 case '/': | |
| 850 *q++ = fileSep; | |
| 851 break; | |
| 852 case ':': | |
| 853 *q++ = pathSep; | |
| 854 break; | |
| 855 default: | |
| 856 *q++ = *p; | |
| 857 } | |
| 858 } | |
| 859 *q = '\0'; | |
| 860 | |
| 861 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched"); | |
| 862 return formatted_path; | |
| 863 } | |
| 864 | |
| 865 | |
| 866 bool os::set_boot_path(char fileSep, char pathSep) { | |
| 867 | |
| 868 const char* home = Arguments::get_java_home(); | |
| 869 int home_len = (int)strlen(home); | |
| 870 | |
| 871 static const char* meta_index_dir_format = "%/lib/"; | |
| 872 static const char* meta_index_format = "%/lib/meta-index"; | |
| 873 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep); | |
| 874 if (meta_index == NULL) return false; | |
| 875 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep); | |
| 876 if (meta_index_dir == NULL) return false; | |
| 877 Arguments::set_meta_index_path(meta_index, meta_index_dir); | |
| 878 | |
| 879 // Any modification to the JAR-file list, for the boot classpath must be | |
| 880 // aligned with install/install/make/common/Pack.gmk. Note: boot class | |
| 881 // path class JARs, are stripped for StackMapTable to reduce download size. | |
| 882 static const char classpath_format[] = | |
| 883 "%/lib/resources.jar:" | |
| 884 "%/lib/rt.jar:" | |
| 885 "%/lib/sunrsasign.jar:" | |
| 886 "%/lib/jsse.jar:" | |
| 887 "%/lib/jce.jar:" | |
| 888 "%/lib/charsets.jar:" | |
| 889 "%/classes"; | |
| 890 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep); | |
| 891 if (sysclasspath == NULL) return false; | |
| 892 Arguments::set_sysclasspath(sysclasspath); | |
| 893 | |
| 894 return true; | |
| 895 } | |
| 896 | |
| 897 void os::set_memory_serialize_page(address page) { | |
| 898 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64); | |
| 899 _mem_serialize_page = (volatile int32_t *)page; | |
| 900 // We initialize the serialization page shift count here | |
| 901 // We assume a cache line size of 64 bytes | |
| 902 assert(SerializePageShiftCount == count, | |
| 903 "thread size changed, fix SerializePageShiftCount constant"); | |
| 904 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t))); | |
| 905 } | |
| 906 | |
|
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907 static volatile intptr_t SerializePageLock = 0; |
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908 |
| 0 | 909 // This method is called from signal handler when SIGSEGV occurs while the current |
| 910 // thread tries to store to the "read-only" memory serialize page during state | |
| 911 // transition. | |
| 912 void os::block_on_serialize_page_trap() { | |
| 913 if (TraceSafepoint) { | |
| 914 tty->print_cr("Block until the serialize page permission restored"); | |
| 915 } | |
|
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916 // When VMThread is holding the SerializePageLock during modifying the |
| 0 | 917 // access permission of the memory serialize page, the following call |
| 918 // will block until the permission of that page is restored to rw. | |
| 919 // Generally, it is unsafe to manipulate locks in signal handlers, but in | |
| 920 // this case, it's OK as the signal is synchronous and we know precisely when | |
|
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921 // it can occur. |
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922 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page"); |
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923 Thread::muxRelease(&SerializePageLock); |
| 0 | 924 } |
| 925 | |
| 926 // Serialize all thread state variables | |
| 927 void os::serialize_thread_states() { | |
| 928 // On some platforms such as Solaris & Linux, the time duration of the page | |
| 929 // permission restoration is observed to be much longer than expected due to | |
| 930 // scheduler starvation problem etc. To avoid the long synchronization | |
|
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931 // time and expensive page trap spinning, 'SerializePageLock' is used to block |
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932 // the mutator thread if such case is encountered. See bug 6546278 for details. |
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933 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states"); |
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934 os::protect_memory((char *)os::get_memory_serialize_page(), |
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935 os::vm_page_size(), MEM_PROT_READ); |
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936 os::protect_memory((char *)os::get_memory_serialize_page(), |
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937 os::vm_page_size(), MEM_PROT_RW); |
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938 Thread::muxRelease(&SerializePageLock); |
| 0 | 939 } |
| 940 | |
| 941 // Returns true if the current stack pointer is above the stack shadow | |
| 942 // pages, false otherwise. | |
| 943 | |
| 944 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) { | |
| 945 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check"); | |
| 946 address sp = current_stack_pointer(); | |
| 947 // Check if we have StackShadowPages above the yellow zone. This parameter | |
| 948 // is dependant on the depth of the maximum VM call stack possible from | |
| 949 // the handler for stack overflow. 'instanceof' in the stack overflow | |
| 950 // handler or a println uses at least 8k stack of VM and native code | |
| 951 // respectively. | |
| 952 const int framesize_in_bytes = | |
| 953 Interpreter::size_top_interpreter_activation(method()) * wordSize; | |
| 954 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages) | |
| 955 * vm_page_size()) + framesize_in_bytes; | |
| 956 // The very lower end of the stack | |
| 957 address stack_limit = thread->stack_base() - thread->stack_size(); | |
| 958 return (sp > (stack_limit + reserved_area)); | |
| 959 } | |
| 960 | |
| 961 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size, | |
| 962 uint min_pages) | |
| 963 { | |
| 964 assert(min_pages > 0, "sanity"); | |
| 965 if (UseLargePages) { | |
| 966 const size_t max_page_size = region_max_size / min_pages; | |
| 967 | |
| 968 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) { | |
| 969 const size_t sz = _page_sizes[i]; | |
| 970 const size_t mask = sz - 1; | |
| 971 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) { | |
| 972 // The largest page size with no fragmentation. | |
| 973 return sz; | |
| 974 } | |
| 975 | |
| 976 if (sz <= max_page_size) { | |
| 977 // The largest page size that satisfies the min_pages requirement. | |
| 978 return sz; | |
| 979 } | |
| 980 } | |
| 981 } | |
| 982 | |
| 983 return vm_page_size(); | |
| 984 } | |
| 985 | |
| 986 #ifndef PRODUCT | |
| 987 void os::trace_page_sizes(const char* str, const size_t region_min_size, | |
| 988 const size_t region_max_size, const size_t page_size, | |
| 989 const char* base, const size_t size) | |
| 990 { | |
| 991 if (TracePageSizes) { | |
| 992 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT | |
| 993 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT | |
| 994 " size=" SIZE_FORMAT, | |
| 995 str, region_min_size, region_max_size, | |
| 996 page_size, base, size); | |
| 997 } | |
| 998 } | |
| 999 #endif // #ifndef PRODUCT | |
| 1000 | |
| 1001 // This is the working definition of a server class machine: | |
| 1002 // >= 2 physical CPU's and >=2GB of memory, with some fuzz | |
| 1003 // because the graphics memory (?) sometimes masks physical memory. | |
| 1004 // If you want to change the definition of a server class machine | |
| 1005 // on some OS or platform, e.g., >=4GB on Windohs platforms, | |
| 1006 // then you'll have to parameterize this method based on that state, | |
| 1007 // as was done for logical processors here, or replicate and | |
| 1008 // specialize this method for each platform. (Or fix os to have | |
| 1009 // some inheritance structure and use subclassing. Sigh.) | |
| 1010 // If you want some platform to always or never behave as a server | |
| 1011 // class machine, change the setting of AlwaysActAsServerClassMachine | |
| 1012 // and NeverActAsServerClassMachine in globals*.hpp. | |
| 1013 bool os::is_server_class_machine() { | |
| 1014 // First check for the early returns | |
| 1015 if (NeverActAsServerClassMachine) { | |
| 1016 return false; | |
| 1017 } | |
| 1018 if (AlwaysActAsServerClassMachine) { | |
| 1019 return true; | |
| 1020 } | |
| 1021 // Then actually look at the machine | |
| 1022 bool result = false; | |
| 1023 const unsigned int server_processors = 2; | |
| 1024 const julong server_memory = 2UL * G; | |
| 1025 // We seem not to get our full complement of memory. | |
| 1026 // We allow some part (1/8?) of the memory to be "missing", | |
| 1027 // based on the sizes of DIMMs, and maybe graphics cards. | |
| 1028 const julong missing_memory = 256UL * M; | |
| 1029 | |
| 1030 /* Is this a server class machine? */ | |
| 1031 if ((os::active_processor_count() >= (int)server_processors) && | |
| 1032 (os::physical_memory() >= (server_memory - missing_memory))) { | |
| 1033 const unsigned int logical_processors = | |
| 1034 VM_Version::logical_processors_per_package(); | |
| 1035 if (logical_processors > 1) { | |
| 1036 const unsigned int physical_packages = | |
| 1037 os::active_processor_count() / logical_processors; | |
| 1038 if (physical_packages > server_processors) { | |
| 1039 result = true; | |
| 1040 } | |
| 1041 } else { | |
| 1042 result = true; | |
| 1043 } | |
| 1044 } | |
| 1045 return result; | |
| 1046 } |