os_bsd_zero.cpp revision 3701:bf2edd3c9b0f
1/* 2 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. 3 * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26#if defined(_ALLBSD_SOURCE) && !defined(__APPLE__) && !defined(__NetBSD__) 27#include <pthread.h> 28# include <pthread_np.h> /* For pthread_attr_get_np */ 29#endif 30 31// no precompiled headers 32#include "assembler_zero.inline.hpp" 33#include "classfile/classLoader.hpp" 34#include "classfile/systemDictionary.hpp" 35#include "classfile/vmSymbols.hpp" 36#include "code/icBuffer.hpp" 37#include "code/vtableStubs.hpp" 38#include "interpreter/interpreter.hpp" 39#include "jvm_bsd.h" 40#include "memory/allocation.inline.hpp" 41#include "mutex_bsd.inline.hpp" 42#include "nativeInst_zero.hpp" 43#include "os_share_bsd.hpp" 44#include "prims/jniFastGetField.hpp" 45#include "prims/jvm.h" 46#include "prims/jvm_misc.hpp" 47#include "runtime/arguments.hpp" 48#include "runtime/extendedPC.hpp" 49#include "runtime/frame.inline.hpp" 50#include "runtime/interfaceSupport.hpp" 51#include "runtime/java.hpp" 52#include "runtime/javaCalls.hpp" 53#include "runtime/mutexLocker.hpp" 54#include "runtime/osThread.hpp" 55#include "runtime/sharedRuntime.hpp" 56#include "runtime/stubRoutines.hpp" 57#include "runtime/timer.hpp" 58#include "thread_bsd.inline.hpp" 59#include "utilities/events.hpp" 60#include "utilities/vmError.hpp" 61 62address os::current_stack_pointer() { 63 address dummy = (address) &dummy; 64 return dummy; 65} 66 67frame os::get_sender_for_C_frame(frame* fr) { 68 ShouldNotCallThis(); 69} 70 71frame os::current_frame() { 72 // The only thing that calls this is the stack printing code in 73 // VMError::report: 74 // - Step 110 (printing stack bounds) uses the sp in the frame 75 // to determine the amount of free space on the stack. We 76 // set the sp to a close approximation of the real value in 77 // order to allow this step to complete. 78 // - Step 120 (printing native stack) tries to walk the stack. 79 // The frame we create has a NULL pc, which is ignored as an 80 // invalid frame. 81 frame dummy = frame(); 82 dummy.set_sp((intptr_t *) current_stack_pointer()); 83 return dummy; 84} 85 86char* os::non_memory_address_word() { 87 // Must never look like an address returned by reserve_memory, 88 // even in its subfields (as defined by the CPU immediate fields, 89 // if the CPU splits constants across multiple instructions). 90#ifdef SPARC 91 // On SPARC, 0 != %hi(any real address), because there is no 92 // allocation in the first 1Kb of the virtual address space. 93 return (char *) 0; 94#else 95 // This is the value for x86; works pretty well for PPC too. 96 return (char *) -1; 97#endif // SPARC 98} 99 100void os::initialize_thread(Thread* thr) { 101 // Nothing to do. 102} 103 104address os::Bsd::ucontext_get_pc(ucontext_t* uc) { 105 ShouldNotCallThis(); 106} 107 108ExtendedPC os::fetch_frame_from_context(void* ucVoid, 109 intptr_t** ret_sp, 110 intptr_t** ret_fp) { 111 ShouldNotCallThis(); 112} 113 114frame os::fetch_frame_from_context(void* ucVoid) { 115 ShouldNotCallThis(); 116} 117 118extern "C" JNIEXPORT int 119JVM_handle_bsd_signal(int sig, 120 siginfo_t* info, 121 void* ucVoid, 122 int abort_if_unrecognized) { 123 ucontext_t* uc = (ucontext_t*) ucVoid; 124 125 Thread* t = ThreadLocalStorage::get_thread_slow(); 126 127 SignalHandlerMark shm(t); 128 129 // Note: it's not uncommon that JNI code uses signal/sigset to 130 // install then restore certain signal handler (e.g. to temporarily 131 // block SIGPIPE, or have a SIGILL handler when detecting CPU 132 // type). When that happens, JVM_handle_bsd_signal() might be 133 // invoked with junk info/ucVoid. To avoid unnecessary crash when 134 // libjsig is not preloaded, try handle signals that do not require 135 // siginfo/ucontext first. 136 137 if (sig == SIGPIPE || sig == SIGXFSZ) { 138 // allow chained handler to go first 139 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 140 return true; 141 } else { 142 if (PrintMiscellaneous && (WizardMode || Verbose)) { 143 char buf[64]; 144 warning("Ignoring %s - see bugs 4229104 or 646499219", 145 os::exception_name(sig, buf, sizeof(buf))); 146 } 147 return true; 148 } 149 } 150 151 JavaThread* thread = NULL; 152 VMThread* vmthread = NULL; 153 if (os::Bsd::signal_handlers_are_installed) { 154 if (t != NULL ){ 155 if(t->is_Java_thread()) { 156 thread = (JavaThread*)t; 157 } 158 else if(t->is_VM_thread()){ 159 vmthread = (VMThread *)t; 160 } 161 } 162 } 163 164 if (info != NULL && thread != NULL) { 165 // Handle ALL stack overflow variations here 166 if (sig == SIGSEGV || sig == SIGBUS) { 167 address addr = (address) info->si_addr; 168 169 // check if fault address is within thread stack 170 if (addr < thread->stack_base() && 171 addr >= thread->stack_base() - thread->stack_size()) { 172 // stack overflow 173 if (thread->in_stack_yellow_zone(addr)) { 174 thread->disable_stack_yellow_zone(); 175 ShouldNotCallThis(); 176 } 177 else if (thread->in_stack_red_zone(addr)) { 178 thread->disable_stack_red_zone(); 179 ShouldNotCallThis(); 180 } 181#ifndef _ALLBSD_SOURCE 182 else { 183 // Accessing stack address below sp may cause SEGV if 184 // current thread has MAP_GROWSDOWN stack. This should 185 // only happen when current thread was created by user 186 // code with MAP_GROWSDOWN flag and then attached to VM. 187 // See notes in os_bsd.cpp. 188 if (thread->osthread()->expanding_stack() == 0) { 189 thread->osthread()->set_expanding_stack(); 190 if (os::Bsd::manually_expand_stack(thread, addr)) { 191 thread->osthread()->clear_expanding_stack(); 192 return true; 193 } 194 thread->osthread()->clear_expanding_stack(); 195 } 196 else { 197 fatal("recursive segv. expanding stack."); 198 } 199 } 200#endif 201 } 202 } 203 204 /*if (thread->thread_state() == _thread_in_Java) { 205 ShouldNotCallThis(); 206 } 207 else*/ if (thread->thread_state() == _thread_in_vm && 208 sig == SIGBUS && thread->doing_unsafe_access()) { 209 ShouldNotCallThis(); 210 } 211 212 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC 213 // kicks in and the heap gets shrunk before the field access. 214 /*if (sig == SIGSEGV || sig == SIGBUS) { 215 address addr = JNI_FastGetField::find_slowcase_pc(pc); 216 if (addr != (address)-1) { 217 stub = addr; 218 } 219 }*/ 220 221 // Check to see if we caught the safepoint code in the process 222 // of write protecting the memory serialization page. It write 223 // enables the page immediately after protecting it so we can 224 // just return to retry the write. 225 if ((sig == SIGSEGV || sig == SIGBUS) && 226 os::is_memory_serialize_page(thread, (address) info->si_addr)) { 227 // Block current thread until permission is restored. 228 os::block_on_serialize_page_trap(); 229 return true; 230 } 231 } 232 233 // signal-chaining 234 if (os::Bsd::chained_handler(sig, info, ucVoid)) { 235 return true; 236 } 237 238 if (!abort_if_unrecognized) { 239 // caller wants another chance, so give it to him 240 return false; 241 } 242 243#ifndef PRODUCT 244 if (sig == SIGSEGV) { 245 fatal("\n#" 246 "\n# /--------------------\\" 247 "\n# | segmentation fault |" 248 "\n# \\---\\ /--------------/" 249 "\n# /" 250 "\n# [-] |\\_/| " 251 "\n# (+)=C |o o|__ " 252 "\n# | | =-*-=__\\ " 253 "\n# OOO c_c_(___)"); 254 } 255#endif // !PRODUCT 256 257 const char *fmt = 258 "caught unhandled signal " INT32_FORMAT " at address " PTR_FORMAT; 259 char buf[128]; 260 261 sprintf(buf, fmt, sig, info->si_addr); 262 fatal(buf); 263} 264 265void os::Bsd::init_thread_fpu_state(void) { 266 // Nothing to do 267} 268 269#ifndef _ALLBSD_SOURCE 270int os::Bsd::get_fpu_control_word() { 271 ShouldNotCallThis(); 272} 273 274void os::Bsd::set_fpu_control_word(int fpu) { 275 ShouldNotCallThis(); 276} 277#endif 278 279bool os::is_allocatable(size_t bytes) { 280#ifdef _LP64 281 return true; 282#else 283 if (bytes < 2 * G) { 284 return true; 285 } 286 287 char* addr = reserve_memory(bytes, NULL); 288 289 if (addr != NULL) { 290 release_memory(addr, bytes); 291 } 292 293 return addr != NULL; 294#endif // _LP64 295} 296 297/////////////////////////////////////////////////////////////////////////////// 298// thread stack 299 300size_t os::Bsd::min_stack_allowed = 64 * K; 301 302bool os::Bsd::supports_variable_stack_size() { 303 return true; 304} 305 306size_t os::Bsd::default_stack_size(os::ThreadType thr_type) { 307#ifdef _LP64 308 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M); 309#else 310 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K); 311#endif // _LP64 312 return s; 313} 314 315size_t os::Bsd::default_guard_size(os::ThreadType thr_type) { 316 // Only enable glibc guard pages for non-Java threads 317 // (Java threads have HotSpot guard pages) 318 return (thr_type == java_thread ? 0 : page_size()); 319} 320 321static void current_stack_region(address *bottom, size_t *size) { 322 address stack_bottom; 323 address stack_top; 324 size_t stack_bytes; 325 326#ifdef __APPLE__ 327 pthread_t self = pthread_self(); 328 stack_top = (address) pthread_get_stackaddr_np(self); 329 stack_bytes = pthread_get_stacksize_np(self); 330 stack_bottom = stack_top - stack_bytes; 331#elif defined(__OpenBSD__) 332 stack_t ss; 333 int rslt = pthread_stackseg_np(pthread_self(), &ss); 334 335 if (rslt != 0) 336 fatal(err_msg("pthread_stackseg_np failed with err = " INT32_FORMAT, 337 rslt)); 338 339 stack_top = (address) ss.ss_sp; 340 stack_bytes = ss.ss_size; 341 stack_bottom = stack_top - stack_bytes; 342#elif defined(_ALLBSD_SOURCE) 343 pthread_attr_t attr; 344 345 int rslt = pthread_attr_init(&attr); 346 347 // JVM needs to know exact stack location, abort if it fails 348 if (rslt != 0) 349 fatal(err_msg("pthread_attr_init failed with err = " INT32_FORMAT, rslt)); 350 351 rslt = pthread_attr_get_np(pthread_self(), &attr); 352 353 if (rslt != 0) 354 fatal(err_msg("pthread_attr_get_np failed with err = " INT32_FORMAT, 355 rslt)); 356 357 if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 || 358 pthread_attr_getstacksize(&attr, &stack_bytes) != 0) { 359 fatal("Can not locate current stack attributes!"); 360 } 361 362 pthread_attr_destroy(&attr); 363 364 stack_top = stack_bottom + stack_bytes; 365#else /* Linux */ 366 pthread_attr_t attr; 367 int res = pthread_getattr_np(pthread_self(), &attr); 368 if (res != 0) { 369 if (res == ENOMEM) { 370 vm_exit_out_of_memory(0, "pthread_getattr_np"); 371 } 372 else { 373 fatal(err_msg("pthread_getattr_np failed with errno = " INT32_FORMAT, 374 res)); 375 } 376 } 377 378 res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes); 379 if (res != 0) { 380 fatal(err_msg("pthread_attr_getstack failed with errno = " INT32_FORMAT, 381 res)); 382 } 383 stack_top = stack_bottom + stack_bytes; 384 385 // The block of memory returned by pthread_attr_getstack() includes 386 // guard pages where present. We need to trim these off. 387 size_t page_bytes = os::Bsd::page_size(); 388 assert(((intptr_t) stack_bottom & (page_bytes - 1)) == 0, "unaligned stack"); 389 390 size_t guard_bytes; 391 res = pthread_attr_getguardsize(&attr, &guard_bytes); 392 if (res != 0) { 393 fatal(err_msg( 394 "pthread_attr_getguardsize failed with errno = " INT32_FORMAT, res)); 395 } 396 int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes; 397 assert(guard_bytes == guard_pages * page_bytes, "unaligned guard"); 398 399#ifdef IA64 400 // IA64 has two stacks sharing the same area of memory, a normal 401 // stack growing downwards and a register stack growing upwards. 402 // Guard pages, if present, are in the centre. This code splits 403 // the stack in two even without guard pages, though in theory 404 // there's nothing to stop us allocating more to the normal stack 405 // or more to the register stack if one or the other were found 406 // to grow faster. 407 int total_pages = align_size_down(stack_bytes, page_bytes) / page_bytes; 408 stack_bottom += (total_pages - guard_pages) / 2 * page_bytes; 409#endif // IA64 410 411 stack_bottom += guard_bytes; 412 413 pthread_attr_destroy(&attr); 414 415 // The initial thread has a growable stack, and the size reported 416 // by pthread_attr_getstack is the maximum size it could possibly 417 // be given what currently mapped. This can be huge, so we cap it. 418 if (os::Bsd::is_initial_thread()) { 419 stack_bytes = stack_top - stack_bottom; 420 421 if (stack_bytes > JavaThread::stack_size_at_create()) 422 stack_bytes = JavaThread::stack_size_at_create(); 423 424 stack_bottom = stack_top - stack_bytes; 425 } 426#endif 427 428 assert(os::current_stack_pointer() >= stack_bottom, "should do"); 429 assert(os::current_stack_pointer() < stack_top, "should do"); 430 431 *bottom = stack_bottom; 432 *size = stack_top - stack_bottom; 433} 434 435address os::current_stack_base() { 436 address bottom; 437 size_t size; 438 current_stack_region(&bottom, &size); 439 return bottom + size; 440} 441 442size_t os::current_stack_size() { 443 // stack size includes normal stack and HotSpot guard pages 444 address bottom; 445 size_t size; 446 current_stack_region(&bottom, &size); 447 return size; 448} 449 450///////////////////////////////////////////////////////////////////////////// 451// helper functions for fatal error handler 452 453void os::print_context(outputStream* st, void* context) { 454 ShouldNotCallThis(); 455} 456 457void os::print_register_info(outputStream *st, void *context) { 458 ShouldNotCallThis(); 459} 460 461///////////////////////////////////////////////////////////////////////////// 462// Stubs for things that would be in bsd_zero.s if it existed. 463// You probably want to disassemble these monkeys to check they're ok. 464 465extern "C" { 466 int SpinPause() { 467 } 468 469 int SafeFetch32(int *adr, int errValue) { 470 int value = errValue; 471 value = *adr; 472 return value; 473 } 474 intptr_t SafeFetchN(intptr_t *adr, intptr_t errValue) { 475 intptr_t value = errValue; 476 value = *adr; 477 return value; 478 } 479 480 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) { 481 if (from > to) { 482 jshort *end = from + count; 483 while (from < end) 484 *(to++) = *(from++); 485 } 486 else if (from < to) { 487 jshort *end = from; 488 from += count - 1; 489 to += count - 1; 490 while (from >= end) 491 *(to--) = *(from--); 492 } 493 } 494 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) { 495 if (from > to) { 496 jint *end = from + count; 497 while (from < end) 498 *(to++) = *(from++); 499 } 500 else if (from < to) { 501 jint *end = from; 502 from += count - 1; 503 to += count - 1; 504 while (from >= end) 505 *(to--) = *(from--); 506 } 507 } 508 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) { 509 if (from > to) { 510 jlong *end = from + count; 511 while (from < end) 512 os::atomic_copy64(from++, to++); 513 } 514 else if (from < to) { 515 jlong *end = from; 516 from += count - 1; 517 to += count - 1; 518 while (from >= end) 519 os::atomic_copy64(from--, to--); 520 } 521 } 522 523 void _Copy_arrayof_conjoint_bytes(HeapWord* from, 524 HeapWord* to, 525 size_t count) { 526 memmove(to, from, count); 527 } 528 void _Copy_arrayof_conjoint_jshorts(HeapWord* from, 529 HeapWord* to, 530 size_t count) { 531 memmove(to, from, count * 2); 532 } 533 void _Copy_arrayof_conjoint_jints(HeapWord* from, 534 HeapWord* to, 535 size_t count) { 536 memmove(to, from, count * 4); 537 } 538 void _Copy_arrayof_conjoint_jlongs(HeapWord* from, 539 HeapWord* to, 540 size_t count) { 541 memmove(to, from, count * 8); 542 } 543}; 544 545///////////////////////////////////////////////////////////////////////////// 546// Implementations of atomic operations not supported by processors. 547// -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html 548 549#ifndef _LP64 550extern "C" { 551 long long unsigned int __sync_val_compare_and_swap_8( 552 volatile void *ptr, 553 long long unsigned int oldval, 554 long long unsigned int newval) { 555 ShouldNotCallThis(); 556 } 557}; 558#endif // !_LP64 559 560#ifndef PRODUCT 561void os::verify_stack_alignment() { 562} 563#endif 564