1 /* 2 * Copyright (c) 2008, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "jvm.h" 27 #include "assembler_arm.inline.hpp" 28 #include "classfile/classLoader.hpp" 29 #include "classfile/systemDictionary.hpp" 30 #include "classfile/vmSymbols.hpp" 31 #include "code/icBuffer.hpp" 32 #include "code/vtableStubs.hpp" 33 #include "interpreter/interpreter.hpp" 34 #include "memory/allocation.inline.hpp" 35 #include "nativeInst_arm.hpp" 36 #include "os_share_linux.hpp" 37 #include "prims/jniFastGetField.hpp" 38 #include "prims/jvm_misc.hpp" 39 #include "runtime/arguments.hpp" 40 #include "runtime/extendedPC.hpp" 41 #include "runtime/frame.inline.hpp" 42 #include "runtime/interfaceSupport.inline.hpp" 43 #include "runtime/java.hpp" 44 #include "runtime/javaCalls.hpp" 45 #include "runtime/mutexLocker.inline.hpp" 46 #include "runtime/osThread.hpp" 47 #include "runtime/sharedRuntime.hpp" 48 #include "runtime/stubRoutines.hpp" 49 #include "runtime/timer.hpp" 50 #include "utilities/debug.hpp" 51 #include "utilities/events.inline.hpp" 52 #include "utilities/vmError.hpp" 53 54 // put OS-includes here 55 # include <sys/types.h> 56 # include <sys/mman.h> 57 # include <pthread.h> 58 # include <signal.h> 59 # include <errno.h> 60 # include <dlfcn.h> 61 # include <stdlib.h> 62 # include <stdio.h> 63 # include <unistd.h> 64 # include <sys/resource.h> 65 # include <pthread.h> 66 # include <sys/stat.h> 67 # include <sys/time.h> 68 # include <sys/utsname.h> 69 # include <sys/socket.h> 70 # include <sys/wait.h> 71 # include <pwd.h> 72 # include <poll.h> 73 # include <ucontext.h> 74 # include <fpu_control.h> 75 # include <asm/ptrace.h> 76 77 #define SPELL_REG_SP "sp" 78 79 // Don't #define SPELL_REG_FP for thumb because it is not safe to use, so this makes sure we never fetch it. 80 #ifndef __thumb__ 81 #define SPELL_REG_FP "fp" 82 #endif 83 84 address os::current_stack_pointer() { 85 register address sp __asm__ (SPELL_REG_SP); 86 return sp; 87 } 88 89 char* os::non_memory_address_word() { 90 // Must never look like an address returned by reserve_memory 91 return (char*) -1; 92 } 93 94 95 #if NGREG == 16 96 // These definitions are based on the observation that until 97 // the certain version of GCC mcontext_t was defined as 98 // a structure containing gregs[NGREG] array with 16 elements. 99 // In later GCC versions mcontext_t was redefined as struct sigcontext, 100 // along with NGREG constant changed to 18. 101 #define arm_pc gregs[15] 102 #define arm_sp gregs[13] 103 #define arm_fp gregs[11] 104 #define arm_r0 gregs[0] 105 #endif 106 107 #define ARM_REGS_IN_CONTEXT 16 108 109 110 address os::Linux::ucontext_get_pc(const ucontext_t* uc) { 111 return (address)uc->uc_mcontext.arm_pc; 112 } 113 114 void os::Linux::ucontext_set_pc(ucontext_t* uc, address pc) { 115 uc->uc_mcontext.arm_pc = (uintx)pc; 116 } 117 118 intptr_t* os::Linux::ucontext_get_sp(const ucontext_t* uc) { 119 return (intptr_t*)uc->uc_mcontext.arm_sp; 120 } 121 122 intptr_t* os::Linux::ucontext_get_fp(const ucontext_t* uc) { 123 return (intptr_t*)uc->uc_mcontext.arm_fp; 124 } 125 126 bool is_safe_for_fp(address pc) { 127 #ifdef __thumb__ 128 if (CodeCache::find_blob(pc) != NULL) { 129 return true; 130 } 131 // For thumb C frames, given an fp we have no idea how to access the frame contents. 132 return false; 133 #else 134 // Calling os::address_is_in_vm() here leads to a dladdr call. Calling any libc 135 // function during os::get_native_stack() can result in a deadlock if JFR is 136 // enabled. For now, be more lenient and allow all pc's. There are other 137 // frame sanity checks in shared code, and to date they have been sufficient 138 // for other platforms. 139 //return os::address_is_in_vm(pc); 140 return true; 141 #endif 142 } 143 144 // For Forte Analyzer AsyncGetCallTrace profiling support - thread 145 // is currently interrupted by SIGPROF. 146 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal 147 // frames. Currently we don't do that on Linux, so it's the same as 148 // os::fetch_frame_from_context(). 149 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread, 150 const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 151 152 assert(thread != NULL, "just checking"); 153 assert(ret_sp != NULL, "just checking"); 154 assert(ret_fp != NULL, "just checking"); 155 156 return os::fetch_frame_from_context(uc, ret_sp, ret_fp); 157 } 158 159 ExtendedPC os::fetch_frame_from_context(const void* ucVoid, 160 intptr_t** ret_sp, intptr_t** ret_fp) { 161 162 ExtendedPC epc; 163 const ucontext_t* uc = (const ucontext_t*)ucVoid; 164 165 if (uc != NULL) { 166 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc)); 167 if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc); 168 if (ret_fp) { 169 intptr_t* fp = os::Linux::ucontext_get_fp(uc); 170 #ifndef __thumb__ 171 if (CodeCache::find_blob(epc.pc()) == NULL) { 172 // It's a C frame. We need to adjust the fp. 173 fp += os::C_frame_offset; 174 } 175 #endif 176 // Clear FP when stack walking is dangerous so that 177 // the frame created will not be walked. 178 // However, ensure FP is set correctly when reliable and 179 // potentially necessary. 180 if (!is_safe_for_fp(epc.pc())) { 181 // FP unreliable 182 fp = (intptr_t *)NULL; 183 } 184 *ret_fp = fp; 185 } 186 } else { 187 // construct empty ExtendedPC for return value checking 188 epc = ExtendedPC(NULL); 189 if (ret_sp) *ret_sp = (intptr_t *)NULL; 190 if (ret_fp) *ret_fp = (intptr_t *)NULL; 191 } 192 193 return epc; 194 } 195 196 frame os::fetch_frame_from_context(const void* ucVoid) { 197 intptr_t* sp; 198 intptr_t* fp; 199 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 200 return frame(sp, fp, epc.pc()); 201 } 202 203 frame os::get_sender_for_C_frame(frame* fr) { 204 #ifdef __thumb__ 205 // We can't reliably get anything from a thumb C frame. 206 return frame(); 207 #else 208 address pc = fr->sender_pc(); 209 if (! is_safe_for_fp(pc)) { 210 return frame(fr->sender_sp(), (intptr_t *)NULL, pc); 211 } else { 212 return frame(fr->sender_sp(), fr->link() + os::C_frame_offset, pc); 213 } 214 #endif 215 } 216 217 // 218 // This actually returns two frames up. It does not return os::current_frame(), 219 // which is the actual current frame. Nor does it return os::get_native_stack(), 220 // which is the caller. It returns whoever called os::get_native_stack(). Not 221 // very intuitive, but consistent with how this API is implemented on other 222 // platforms. 223 // 224 frame os::current_frame() { 225 #ifdef __thumb__ 226 // We can't reliably get anything from a thumb C frame. 227 return frame(); 228 #else 229 register intptr_t* fp __asm__ (SPELL_REG_FP); 230 // fp is for os::current_frame. We want the fp for our caller. 231 frame myframe((intptr_t*)os::current_stack_pointer(), fp + os::C_frame_offset, 232 CAST_FROM_FN_PTR(address, os::current_frame)); 233 frame caller_frame = os::get_sender_for_C_frame(&myframe); 234 235 if (os::is_first_C_frame(&caller_frame)) { 236 // stack is not walkable 237 // Assert below was added because it does not seem like this can ever happen. 238 // How can this frame ever be the first C frame since it is called from C code? 239 // If it does ever happen, undo the assert and comment here on when/why it happens. 240 assert(false, "this should never happen"); 241 return frame(); 242 } 243 244 // return frame for our caller's caller 245 return os::get_sender_for_C_frame(&caller_frame); 246 #endif 247 } 248 249 extern "C" address check_vfp_fault_instr; 250 extern "C" address check_vfp3_32_fault_instr; 251 extern "C" address check_simd_fault_instr; 252 extern "C" address check_mp_ext_fault_instr; 253 254 address check_vfp_fault_instr = NULL; 255 address check_vfp3_32_fault_instr = NULL; 256 address check_simd_fault_instr = NULL; 257 address check_mp_ext_fault_instr = NULL; 258 259 // Utility functions 260 261 extern "C" int JVM_handle_linux_signal(int sig, siginfo_t* info, 262 void* ucVoid, int abort_if_unrecognized) { 263 ucontext_t* uc = (ucontext_t*) ucVoid; 264 265 Thread* t = Thread::current_or_null_safe(); 266 267 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away 268 // (no destructors can be run) 269 os::ThreadCrashProtection::check_crash_protection(sig, t); 270 271 SignalHandlerMark shm(t); 272 273 if (sig == SIGILL && 274 ((info->si_addr == (caddr_t)check_simd_fault_instr) 275 || info->si_addr == (caddr_t)check_vfp_fault_instr 276 || info->si_addr == (caddr_t)check_vfp3_32_fault_instr 277 || info->si_addr == (caddr_t)check_mp_ext_fault_instr)) { 278 // skip faulty instruction + instruction that sets return value to 279 // success and set return value to failure. 280 os::Linux::ucontext_set_pc(uc, (address)info->si_addr + 8); 281 uc->uc_mcontext.arm_r0 = 0; 282 return true; 283 } 284 285 // Note: it's not uncommon that JNI code uses signal/sigset to install 286 // then restore certain signal handler (e.g. to temporarily block SIGPIPE, 287 // or have a SIGILL handler when detecting CPU type). When that happens, 288 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To 289 // avoid unnecessary crash when libjsig is not preloaded, try handle signals 290 // that do not require siginfo/ucontext first. 291 292 if (sig == SIGPIPE || sig == SIGXFSZ) { 293 // allow chained handler to go first 294 if (os::Linux::chained_handler(sig, info, ucVoid)) { 295 return true; 296 } else { 297 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219 298 return true; 299 } 300 } 301 302 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT 303 if ((sig == SIGSEGV || sig == SIGBUS) && info != NULL && info->si_addr == g_assert_poison) { 304 if (handle_assert_poison_fault(ucVoid, info->si_addr)) { 305 return 1; 306 } 307 } 308 #endif 309 310 JavaThread* thread = NULL; 311 VMThread* vmthread = NULL; 312 if (os::Linux::signal_handlers_are_installed) { 313 if (t != NULL ){ 314 if(t->is_Java_thread()) { 315 thread = (JavaThread*)t; 316 } 317 else if(t->is_VM_thread()){ 318 vmthread = (VMThread *)t; 319 } 320 } 321 } 322 323 address stub = NULL; 324 address pc = NULL; 325 bool unsafe_access = false; 326 327 if (info != NULL && uc != NULL && thread != NULL) { 328 pc = (address) os::Linux::ucontext_get_pc(uc); 329 330 // Handle ALL stack overflow variations here 331 if (sig == SIGSEGV) { 332 address addr = (address) info->si_addr; 333 334 if (StubRoutines::is_safefetch_fault(pc)) { 335 os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc)); 336 return 1; 337 } 338 // check if fault address is within thread stack 339 if (addr < thread->stack_base() && 340 addr >= thread->stack_base() - thread->stack_size()) { 341 // stack overflow 342 if (thread->in_stack_yellow_reserved_zone(addr)) { 343 thread->disable_stack_yellow_reserved_zone(); 344 if (thread->thread_state() == _thread_in_Java) { 345 // Throw a stack overflow exception. Guard pages will be reenabled 346 // while unwinding the stack. 347 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 348 } else { 349 // Thread was in the vm or native code. Return and try to finish. 350 return 1; 351 } 352 } else if (thread->in_stack_red_zone(addr)) { 353 // Fatal red zone violation. Disable the guard pages and fall through 354 // to handle_unexpected_exception way down below. 355 thread->disable_stack_red_zone(); 356 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 357 } else { 358 // Accessing stack address below sp may cause SEGV if current 359 // thread has MAP_GROWSDOWN stack. This should only happen when 360 // current thread was created by user code with MAP_GROWSDOWN flag 361 // and then attached to VM. See notes in os_linux.cpp. 362 if (thread->osthread()->expanding_stack() == 0) { 363 thread->osthread()->set_expanding_stack(); 364 if (os::Linux::manually_expand_stack(thread, addr)) { 365 thread->osthread()->clear_expanding_stack(); 366 return 1; 367 } 368 thread->osthread()->clear_expanding_stack(); 369 } else { 370 fatal("recursive segv. expanding stack."); 371 } 372 } 373 } 374 } 375 376 if (thread->thread_state() == _thread_in_Java) { 377 // Java thread running in Java code => find exception handler if any 378 // a fault inside compiled code, the interpreter, or a stub 379 380 if (sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 381 stub = SharedRuntime::get_poll_stub(pc); 382 } else if (sig == SIGBUS) { 383 // BugId 4454115: A read from a MappedByteBuffer can fault 384 // here if the underlying file has been truncated. 385 // Do not crash the VM in such a case. 386 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 387 CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL; 388 if ((nm != NULL && nm->has_unsafe_access()) || (thread->doing_unsafe_access() && UnsafeCopyMemory::contains_pc(pc))) { 389 unsafe_access = true; 390 } 391 } else if (sig == SIGSEGV && 392 MacroAssembler::uses_implicit_null_check(info->si_addr)) { 393 // Determination of interpreter/vtable stub/compiled code null exception 394 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 395 if (cb != NULL) { 396 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 397 } 398 } else if (sig == SIGILL && *(int *)pc == NativeInstruction::zombie_illegal_instruction) { 399 // Zombie 400 stub = SharedRuntime::get_handle_wrong_method_stub(); 401 } 402 } else if ((thread->thread_state() == _thread_in_vm || 403 thread->thread_state() == _thread_in_native) && 404 sig == SIGBUS && thread->doing_unsafe_access()) { 405 unsafe_access = true; 406 } 407 408 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 409 // and the heap gets shrunk before the field access. 410 if (sig == SIGSEGV || sig == SIGBUS) { 411 address addr = JNI_FastGetField::find_slowcase_pc(pc); 412 if (addr != (address)-1) { 413 stub = addr; 414 } 415 } 416 } 417 418 if (unsafe_access && stub == NULL) { 419 // it can be an unsafe access and we haven't found 420 // any other suitable exception reason, 421 // so assume it is an unsafe access. 422 address next_pc = pc + Assembler::InstructionSize; 423 if (UnsafeCopyMemory::contains_pc(pc)) { 424 next_pc = UnsafeCopyMemory::page_error_continue_pc(pc); 425 } 426 #ifdef __thumb__ 427 if (uc->uc_mcontext.arm_cpsr & PSR_T_BIT) { 428 next_pc = (address)((intptr_t)next_pc | 0x1); 429 } 430 #endif 431 432 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 433 } 434 435 if (stub != NULL) { 436 #ifdef __thumb__ 437 if (uc->uc_mcontext.arm_cpsr & PSR_T_BIT) { 438 intptr_t p = (intptr_t)pc | 0x1; 439 pc = (address)p; 440 441 // Clear Thumb mode bit if we're redirected into the ARM ISA based code 442 if (((intptr_t)stub & 0x1) == 0) { 443 uc->uc_mcontext.arm_cpsr &= ~PSR_T_BIT; 444 } 445 } else { 446 // No Thumb2 compiled stubs are triggered from ARM ISA compiled JIT'd code today. 447 // The support needs to be added if that changes 448 assert((((intptr_t)stub & 0x1) == 0), "can't return to Thumb code"); 449 } 450 #endif 451 452 // save all thread context in case we need to restore it 453 if (thread != NULL) thread->set_saved_exception_pc(pc); 454 455 os::Linux::ucontext_set_pc(uc, stub); 456 return true; 457 } 458 459 // signal-chaining 460 if (os::Linux::chained_handler(sig, info, ucVoid)) { 461 return true; 462 } 463 464 if (!abort_if_unrecognized) { 465 // caller wants another chance, so give it to him 466 return false; 467 } 468 469 if (pc == NULL && uc != NULL) { 470 pc = os::Linux::ucontext_get_pc(uc); 471 } 472 473 // unmask current signal 474 sigset_t newset; 475 sigemptyset(&newset); 476 sigaddset(&newset, sig); 477 sigprocmask(SIG_UNBLOCK, &newset, NULL); 478 479 VMError::report_and_die(t, sig, pc, info, ucVoid); 480 481 ShouldNotReachHere(); 482 return false; 483 } 484 485 void os::Linux::init_thread_fpu_state(void) { 486 os::setup_fpu(); 487 } 488 489 int os::Linux::get_fpu_control_word(void) { 490 return 0; 491 } 492 493 void os::Linux::set_fpu_control_word(int fpu_control) { 494 // Nothing to do 495 } 496 497 void os::setup_fpu() { 498 #if !defined(__SOFTFP__) && defined(__VFP_FP__) 499 // Turn on IEEE-754 compliant VFP mode 500 __asm__ volatile ( 501 "mov %%r0, #0;" 502 "fmxr fpscr, %%r0" 503 : /* no output */ : /* no input */ : "r0" 504 ); 505 #endif 506 } 507 508 bool os::is_allocatable(size_t bytes) { 509 return true; 510 } 511 512 //////////////////////////////////////////////////////////////////////////////// 513 // thread stack 514 515 // Minimum usable stack sizes required to get to user code. Space for 516 // HotSpot guard pages is added later. 517 size_t os::Posix::_compiler_thread_min_stack_allowed = (32 DEBUG_ONLY(+ 4)) * K; 518 size_t os::Posix::_java_thread_min_stack_allowed = (32 DEBUG_ONLY(+ 4)) * K; 519 size_t os::Posix::_vm_internal_thread_min_stack_allowed = (48 DEBUG_ONLY(+ 4)) * K; 520 521 // return default stack size for thr_type 522 size_t os::Posix::default_stack_size(os::ThreadType thr_type) { 523 // default stack size (compiler thread needs larger stack) 524 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K); 525 return s; 526 } 527 528 ///////////////////////////////////////////////////////////////////////////// 529 // helper functions for fatal error handler 530 531 void os::print_context(outputStream *st, const void *context) { 532 if (context == NULL) return; 533 const ucontext_t *uc = (const ucontext_t*)context; 534 535 st->print_cr("Registers:"); 536 intx* reg_area = (intx*)&uc->uc_mcontext.arm_r0; 537 for (int r = 0; r < ARM_REGS_IN_CONTEXT; r++) { 538 st->print_cr(" %-3s = " INTPTR_FORMAT, as_Register(r)->name(), reg_area[r]); 539 } 540 #define U64_FORMAT "0x%016llx" 541 // now print flag register 542 st->print_cr(" %-4s = 0x%08lx", "cpsr",uc->uc_mcontext.arm_cpsr); 543 st->cr(); 544 545 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc); 546 st->print_cr("Top of Stack: (sp=" INTPTR_FORMAT ")", p2i(sp)); 547 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 548 st->cr(); 549 550 // Note: it may be unsafe to inspect memory near pc. For example, pc may 551 // point to garbage if entry point in an nmethod is corrupted. Leave 552 // this at the end, and hope for the best. 553 address pc = os::Linux::ucontext_get_pc(uc); 554 print_instructions(st, pc, Assembler::InstructionSize); 555 st->cr(); 556 } 557 558 void os::print_register_info(outputStream *st, const void *context) { 559 if (context == NULL) return; 560 561 const ucontext_t *uc = (const ucontext_t*)context; 562 intx* reg_area = (intx*)&uc->uc_mcontext.arm_r0; 563 564 st->print_cr("Register to memory mapping:"); 565 st->cr(); 566 for (int r = 0; r < ARM_REGS_IN_CONTEXT; r++) { 567 st->print_cr(" %-3s = " INTPTR_FORMAT, as_Register(r)->name(), reg_area[r]); 568 print_location(st, reg_area[r]); 569 st->cr(); 570 } 571 st->cr(); 572 } 573 574 575 576 typedef int64_t cmpxchg_long_func_t(int64_t, int64_t, volatile int64_t*); 577 578 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 579 580 int64_t os::atomic_cmpxchg_long_bootstrap(int64_t compare_value, int64_t exchange_value, volatile int64_t* dest) { 581 // try to use the stub: 582 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 583 584 if (func != NULL) { 585 os::atomic_cmpxchg_long_func = func; 586 return (*func)(compare_value, exchange_value, dest); 587 } 588 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 589 590 int64_t old_value = *dest; 591 if (old_value == compare_value) 592 *dest = exchange_value; 593 return old_value; 594 } 595 typedef int64_t load_long_func_t(const volatile int64_t*); 596 597 load_long_func_t* os::atomic_load_long_func = os::atomic_load_long_bootstrap; 598 599 int64_t os::atomic_load_long_bootstrap(const volatile int64_t* src) { 600 // try to use the stub: 601 load_long_func_t* func = CAST_TO_FN_PTR(load_long_func_t*, StubRoutines::atomic_load_long_entry()); 602 603 if (func != NULL) { 604 os::atomic_load_long_func = func; 605 return (*func)(src); 606 } 607 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 608 609 int64_t old_value = *src; 610 return old_value; 611 } 612 613 typedef void store_long_func_t(int64_t, volatile int64_t*); 614 615 store_long_func_t* os::atomic_store_long_func = os::atomic_store_long_bootstrap; 616 617 void os::atomic_store_long_bootstrap(int64_t val, volatile int64_t* dest) { 618 // try to use the stub: 619 store_long_func_t* func = CAST_TO_FN_PTR(store_long_func_t*, StubRoutines::atomic_store_long_entry()); 620 621 if (func != NULL) { 622 os::atomic_store_long_func = func; 623 return (*func)(val, dest); 624 } 625 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 626 627 *dest = val; 628 } 629 630 typedef int32_t atomic_add_func_t(int32_t add_value, volatile int32_t *dest); 631 632 atomic_add_func_t * os::atomic_add_func = os::atomic_add_bootstrap; 633 634 int32_t os::atomic_add_bootstrap(int32_t add_value, volatile int32_t *dest) { 635 atomic_add_func_t * func = CAST_TO_FN_PTR(atomic_add_func_t*, 636 StubRoutines::atomic_add_entry()); 637 if (func != NULL) { 638 os::atomic_add_func = func; 639 return (*func)(add_value, dest); 640 } 641 642 int32_t old_value = *dest; 643 *dest = old_value + add_value; 644 return (old_value + add_value); 645 } 646 647 typedef int32_t atomic_xchg_func_t(int32_t exchange_value, volatile int32_t *dest); 648 649 atomic_xchg_func_t * os::atomic_xchg_func = os::atomic_xchg_bootstrap; 650 651 int32_t os::atomic_xchg_bootstrap(int32_t exchange_value, volatile int32_t *dest) { 652 atomic_xchg_func_t * func = CAST_TO_FN_PTR(atomic_xchg_func_t*, 653 StubRoutines::atomic_xchg_entry()); 654 if (func != NULL) { 655 os::atomic_xchg_func = func; 656 return (*func)(exchange_value, dest); 657 } 658 659 int32_t old_value = *dest; 660 *dest = exchange_value; 661 return (old_value); 662 } 663 664 typedef int32_t cmpxchg_func_t(int32_t, int32_t, volatile int32_t*); 665 666 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 667 668 int32_t os::atomic_cmpxchg_bootstrap(int32_t compare_value, int32_t exchange_value, volatile int32_t* dest) { 669 // try to use the stub: 670 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 671 672 if (func != NULL) { 673 os::atomic_cmpxchg_func = func; 674 return (*func)(compare_value, exchange_value, dest); 675 } 676 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 677 678 int32_t old_value = *dest; 679 if (old_value == compare_value) 680 *dest = exchange_value; 681 return old_value; 682 } 683 684 685 #ifndef PRODUCT 686 void os::verify_stack_alignment() { 687 } 688 #endif 689 690 int os::extra_bang_size_in_bytes() { 691 // ARM does not require an additional stack bang. 692 return 0; 693 }