os_bsd.cpp revision 5947:f4f6ae481e1a
1/* 2 * Copyright (c) 1999, 2013, 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 "classfile/classLoader.hpp" 27#include "classfile/systemDictionary.hpp" 28#include "classfile/vmSymbols.hpp" 29#include "code/icBuffer.hpp" 30#include "code/vtableStubs.hpp" 31#include "compiler/compileBroker.hpp" 32#include "compiler/disassembler.hpp" 33#include "interpreter/interpreter.hpp" 34#include "jvm_bsd.h" 35#include "memory/allocation.inline.hpp" 36#include "memory/filemap.hpp" 37#include "mutex_bsd.inline.hpp" 38#include "oops/oop.inline.hpp" 39#include "os_share_bsd.hpp" 40#include "prims/jniFastGetField.hpp" 41#include "prims/jvm.h" 42#include "prims/jvm_misc.hpp" 43#include "runtime/arguments.hpp" 44#include "runtime/extendedPC.hpp" 45#include "runtime/globals.hpp" 46#include "runtime/interfaceSupport.hpp" 47#include "runtime/java.hpp" 48#include "runtime/javaCalls.hpp" 49#include "runtime/mutexLocker.hpp" 50#include "runtime/objectMonitor.hpp" 51#include "runtime/osThread.hpp" 52#include "runtime/perfMemory.hpp" 53#include "runtime/sharedRuntime.hpp" 54#include "runtime/statSampler.hpp" 55#include "runtime/stubRoutines.hpp" 56#include "runtime/thread.inline.hpp" 57#include "runtime/threadCritical.hpp" 58#include "runtime/timer.hpp" 59#include "services/attachListener.hpp" 60#include "services/memTracker.hpp" 61#include "services/runtimeService.hpp" 62#include "utilities/decoder.hpp" 63#include "utilities/defaultStream.hpp" 64#include "utilities/events.hpp" 65#include "utilities/growableArray.hpp" 66#include "utilities/vmError.hpp" 67 68// put OS-includes here 69# include <sys/types.h> 70# include <sys/mman.h> 71# include <sys/stat.h> 72# include <sys/select.h> 73# include <pthread.h> 74# include <signal.h> 75# include <errno.h> 76# include <dlfcn.h> 77# include <stdio.h> 78# include <unistd.h> 79# include <sys/resource.h> 80# include <pthread.h> 81# include <sys/stat.h> 82# include <sys/time.h> 83# include <sys/times.h> 84# include <sys/utsname.h> 85# include <sys/socket.h> 86# include <sys/wait.h> 87# include <time.h> 88# include <pwd.h> 89# include <poll.h> 90# include <semaphore.h> 91# include <fcntl.h> 92# include <string.h> 93# include <sys/param.h> 94# include <sys/sysctl.h> 95# include <sys/ipc.h> 96# include <sys/shm.h> 97#ifndef __APPLE__ 98# include <link.h> 99#endif 100# include <stdint.h> 101# include <inttypes.h> 102# include <sys/ioctl.h> 103 104#if defined(__FreeBSD__) || defined(__NetBSD__) 105# include <elf.h> 106#endif 107 108#ifdef __APPLE__ 109# include <mach/mach.h> // semaphore_* API 110# include <mach-o/dyld.h> 111# include <sys/proc_info.h> 112# include <objc/objc-auto.h> 113#endif 114 115#ifndef MAP_ANONYMOUS 116#define MAP_ANONYMOUS MAP_ANON 117#endif 118 119#define MAX_PATH (2 * K) 120 121// for timer info max values which include all bits 122#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 123 124#define LARGEPAGES_BIT (1 << 6) 125//////////////////////////////////////////////////////////////////////////////// 126// global variables 127julong os::Bsd::_physical_memory = 0; 128 129 130int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 131pthread_t os::Bsd::_main_thread; 132int os::Bsd::_page_size = -1; 133 134static jlong initial_time_count=0; 135 136static int clock_tics_per_sec = 100; 137 138// For diagnostics to print a message once. see run_periodic_checks 139static sigset_t check_signal_done; 140static bool check_signals = true; 141 142static pid_t _initial_pid = 0; 143 144/* Signal number used to suspend/resume a thread */ 145 146/* do not use any signal number less than SIGSEGV, see 4355769 */ 147static int SR_signum = SIGUSR2; 148sigset_t SR_sigset; 149 150 151//////////////////////////////////////////////////////////////////////////////// 152// utility functions 153 154static int SR_initialize(); 155 156julong os::available_memory() { 157 return Bsd::available_memory(); 158} 159 160julong os::Bsd::available_memory() { 161 // XXXBSD: this is just a stopgap implementation 162 return physical_memory() >> 2; 163} 164 165julong os::physical_memory() { 166 return Bsd::physical_memory(); 167} 168 169//////////////////////////////////////////////////////////////////////////////// 170// environment support 171 172bool os::getenv(const char* name, char* buf, int len) { 173 const char* val = ::getenv(name); 174 if (val != NULL && strlen(val) < (size_t)len) { 175 strcpy(buf, val); 176 return true; 177 } 178 if (len > 0) buf[0] = 0; // return a null string 179 return false; 180} 181 182 183// Return true if user is running as root. 184 185bool os::have_special_privileges() { 186 static bool init = false; 187 static bool privileges = false; 188 if (!init) { 189 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 190 init = true; 191 } 192 return privileges; 193} 194 195 196 197// Cpu architecture string 198#if defined(ZERO) 199static char cpu_arch[] = ZERO_LIBARCH; 200#elif defined(IA64) 201static char cpu_arch[] = "ia64"; 202#elif defined(IA32) 203static char cpu_arch[] = "i386"; 204#elif defined(AMD64) 205static char cpu_arch[] = "amd64"; 206#elif defined(ARM) 207static char cpu_arch[] = "arm"; 208#elif defined(PPC32) 209static char cpu_arch[] = "ppc"; 210#elif defined(SPARC) 211# ifdef _LP64 212static char cpu_arch[] = "sparcv9"; 213# else 214static char cpu_arch[] = "sparc"; 215# endif 216#else 217#error Add appropriate cpu_arch setting 218#endif 219 220// Compiler variant 221#ifdef COMPILER2 222#define COMPILER_VARIANT "server" 223#else 224#define COMPILER_VARIANT "client" 225#endif 226 227 228void os::Bsd::initialize_system_info() { 229 int mib[2]; 230 size_t len; 231 int cpu_val; 232 julong mem_val; 233 234 /* get processors count via hw.ncpus sysctl */ 235 mib[0] = CTL_HW; 236 mib[1] = HW_NCPU; 237 len = sizeof(cpu_val); 238 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 239 assert(len == sizeof(cpu_val), "unexpected data size"); 240 set_processor_count(cpu_val); 241 } 242 else { 243 set_processor_count(1); // fallback 244 } 245 246 /* get physical memory via hw.memsize sysctl (hw.memsize is used 247 * since it returns a 64 bit value) 248 */ 249 mib[0] = CTL_HW; 250 mib[1] = HW_MEMSIZE; 251 len = sizeof(mem_val); 252 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 253 assert(len == sizeof(mem_val), "unexpected data size"); 254 _physical_memory = mem_val; 255 } else { 256 _physical_memory = 256*1024*1024; // fallback (XXXBSD?) 257 } 258 259#ifdef __OpenBSD__ 260 { 261 // limit _physical_memory memory view on OpenBSD since 262 // datasize rlimit restricts us anyway. 263 struct rlimit limits; 264 getrlimit(RLIMIT_DATA, &limits); 265 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 266 } 267#endif 268} 269 270#ifdef __APPLE__ 271static const char *get_home() { 272 const char *home_dir = ::getenv("HOME"); 273 if ((home_dir == NULL) || (*home_dir == '\0')) { 274 struct passwd *passwd_info = getpwuid(geteuid()); 275 if (passwd_info != NULL) { 276 home_dir = passwd_info->pw_dir; 277 } 278 } 279 280 return home_dir; 281} 282#endif 283 284void os::init_system_properties_values() { 285// char arch[12]; 286// sysinfo(SI_ARCHITECTURE, arch, sizeof(arch)); 287 288 // The next steps are taken in the product version: 289 // 290 // Obtain the JAVA_HOME value from the location of libjvm.so. 291 // This library should be located at: 292 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 293 // 294 // If "/jre/lib/" appears at the right place in the path, then we 295 // assume libjvm.so is installed in a JDK and we use this path. 296 // 297 // Otherwise exit with message: "Could not create the Java virtual machine." 298 // 299 // The following extra steps are taken in the debugging version: 300 // 301 // If "/jre/lib/" does NOT appear at the right place in the path 302 // instead of exit check for $JAVA_HOME environment variable. 303 // 304 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 305 // then we append a fake suffix "hotspot/libjvm.so" to this path so 306 // it looks like libjvm.so is installed there 307 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 308 // 309 // Otherwise exit. 310 // 311 // Important note: if the location of libjvm.so changes this 312 // code needs to be changed accordingly. 313 314 // The next few definitions allow the code to be verbatim: 315#define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal) 316#define getenv(n) ::getenv(n) 317 318/* 319 * See ld(1): 320 * The linker uses the following search paths to locate required 321 * shared libraries: 322 * 1: ... 323 * ... 324 * 7: The default directories, normally /lib and /usr/lib. 325 */ 326#ifndef DEFAULT_LIBPATH 327#define DEFAULT_LIBPATH "/lib:/usr/lib" 328#endif 329 330#define EXTENSIONS_DIR "/lib/ext" 331#define ENDORSED_DIR "/lib/endorsed" 332#define REG_DIR "/usr/java/packages" 333 334#ifdef __APPLE__ 335#define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 336#define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 337 const char *user_home_dir = get_home(); 338 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir 339 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 340 sizeof(SYS_EXTENSIONS_DIRS); 341#endif 342 343 { 344 /* sysclasspath, java_home, dll_dir */ 345 { 346 char *home_path; 347 char *dll_path; 348 char *pslash; 349 char buf[MAXPATHLEN]; 350 os::jvm_path(buf, sizeof(buf)); 351 352 // Found the full path to libjvm.so. 353 // Now cut the path to <java_home>/jre if we can. 354 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */ 355 pslash = strrchr(buf, '/'); 356 if (pslash != NULL) 357 *pslash = '\0'; /* get rid of /{client|server|hotspot} */ 358 dll_path = malloc(strlen(buf) + 1); 359 if (dll_path == NULL) 360 return; 361 strcpy(dll_path, buf); 362 Arguments::set_dll_dir(dll_path); 363 364 if (pslash != NULL) { 365 pslash = strrchr(buf, '/'); 366 if (pslash != NULL) { 367 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */ 368#ifndef __APPLE__ 369 pslash = strrchr(buf, '/'); 370 if (pslash != NULL) 371 *pslash = '\0'; /* get rid of /lib */ 372#endif 373 } 374 } 375 376 home_path = malloc(strlen(buf) + 1); 377 if (home_path == NULL) 378 return; 379 strcpy(home_path, buf); 380 Arguments::set_java_home(home_path); 381 382 if (!set_boot_path('/', ':')) 383 return; 384 } 385 386 /* 387 * Where to look for native libraries 388 * 389 * Note: Due to a legacy implementation, most of the library path 390 * is set in the launcher. This was to accomodate linking restrictions 391 * on legacy Bsd implementations (which are no longer supported). 392 * Eventually, all the library path setting will be done here. 393 * 394 * However, to prevent the proliferation of improperly built native 395 * libraries, the new path component /usr/java/packages is added here. 396 * Eventually, all the library path setting will be done here. 397 */ 398 { 399 char *ld_library_path; 400 401 /* 402 * Construct the invariant part of ld_library_path. Note that the 403 * space for the colon and the trailing null are provided by the 404 * nulls included by the sizeof operator (so actually we allocate 405 * a byte more than necessary). 406 */ 407#ifdef __APPLE__ 408 ld_library_path = (char *) malloc(system_ext_size); 409 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir); 410#else 411 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") + 412 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH)); 413 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch); 414#endif 415 416 /* 417 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It 418 * should always exist (until the legacy problem cited above is 419 * addressed). 420 */ 421#ifdef __APPLE__ 422 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper 423 char *l = getenv("JAVA_LIBRARY_PATH"); 424 if (l != NULL) { 425 char *t = ld_library_path; 426 /* That's +1 for the colon and +1 for the trailing '\0' */ 427 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1); 428 sprintf(ld_library_path, "%s:%s", l, t); 429 free(t); 430 } 431 432 char *v = getenv("DYLD_LIBRARY_PATH"); 433#else 434 char *v = getenv("LD_LIBRARY_PATH"); 435#endif 436 if (v != NULL) { 437 char *t = ld_library_path; 438 /* That's +1 for the colon and +1 for the trailing '\0' */ 439 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1); 440 sprintf(ld_library_path, "%s:%s", v, t); 441 free(t); 442 } 443 444#ifdef __APPLE__ 445 // Apple's Java6 has "." at the beginning of java.library.path. 446 // OpenJDK on Windows has "." at the end of java.library.path. 447 // OpenJDK on Linux and Solaris don't have "." in java.library.path 448 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 449 // "." is appended to the end of java.library.path. Yes, this 450 // could cause a change in behavior, but Apple's Java6 behavior 451 // can be achieved by putting "." at the beginning of the 452 // JAVA_LIBRARY_PATH environment variable. 453 { 454 char *t = ld_library_path; 455 // that's +3 for appending ":." and the trailing '\0' 456 ld_library_path = (char *) malloc(strlen(t) + 3); 457 sprintf(ld_library_path, "%s:%s", t, "."); 458 free(t); 459 } 460#endif 461 462 Arguments::set_library_path(ld_library_path); 463 } 464 465 /* 466 * Extensions directories. 467 * 468 * Note that the space for the colon and the trailing null are provided 469 * by the nulls included by the sizeof operator (so actually one byte more 470 * than necessary is allocated). 471 */ 472 { 473#ifdef __APPLE__ 474 char *buf = malloc(strlen(Arguments::get_java_home()) + 475 sizeof(EXTENSIONS_DIR) + system_ext_size); 476 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" 477 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home()); 478#else 479 char *buf = malloc(strlen(Arguments::get_java_home()) + 480 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR)); 481 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR, 482 Arguments::get_java_home()); 483#endif 484 485 Arguments::set_ext_dirs(buf); 486 } 487 488 /* Endorsed standards default directory. */ 489 { 490 char * buf; 491 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR)); 492 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 493 Arguments::set_endorsed_dirs(buf); 494 } 495 } 496 497#ifdef __APPLE__ 498#undef SYS_EXTENSIONS_DIR 499#endif 500#undef malloc 501#undef getenv 502#undef EXTENSIONS_DIR 503#undef ENDORSED_DIR 504 505 // Done 506 return; 507} 508 509//////////////////////////////////////////////////////////////////////////////// 510// breakpoint support 511 512void os::breakpoint() { 513 BREAKPOINT; 514} 515 516extern "C" void breakpoint() { 517 // use debugger to set breakpoint here 518} 519 520//////////////////////////////////////////////////////////////////////////////// 521// signal support 522 523debug_only(static bool signal_sets_initialized = false); 524static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 525 526bool os::Bsd::is_sig_ignored(int sig) { 527 struct sigaction oact; 528 sigaction(sig, (struct sigaction*)NULL, &oact); 529 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 530 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 531 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 532 return true; 533 else 534 return false; 535} 536 537void os::Bsd::signal_sets_init() { 538 // Should also have an assertion stating we are still single-threaded. 539 assert(!signal_sets_initialized, "Already initialized"); 540 // Fill in signals that are necessarily unblocked for all threads in 541 // the VM. Currently, we unblock the following signals: 542 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 543 // by -Xrs (=ReduceSignalUsage)); 544 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 545 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 546 // the dispositions or masks wrt these signals. 547 // Programs embedding the VM that want to use the above signals for their 548 // own purposes must, at this time, use the "-Xrs" option to prevent 549 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 550 // (See bug 4345157, and other related bugs). 551 // In reality, though, unblocking these signals is really a nop, since 552 // these signals are not blocked by default. 553 sigemptyset(&unblocked_sigs); 554 sigemptyset(&allowdebug_blocked_sigs); 555 sigaddset(&unblocked_sigs, SIGILL); 556 sigaddset(&unblocked_sigs, SIGSEGV); 557 sigaddset(&unblocked_sigs, SIGBUS); 558 sigaddset(&unblocked_sigs, SIGFPE); 559 sigaddset(&unblocked_sigs, SR_signum); 560 561 if (!ReduceSignalUsage) { 562 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 563 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 564 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 565 } 566 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 567 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 568 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 569 } 570 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 571 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 572 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 573 } 574 } 575 // Fill in signals that are blocked by all but the VM thread. 576 sigemptyset(&vm_sigs); 577 if (!ReduceSignalUsage) 578 sigaddset(&vm_sigs, BREAK_SIGNAL); 579 debug_only(signal_sets_initialized = true); 580 581} 582 583// These are signals that are unblocked while a thread is running Java. 584// (For some reason, they get blocked by default.) 585sigset_t* os::Bsd::unblocked_signals() { 586 assert(signal_sets_initialized, "Not initialized"); 587 return &unblocked_sigs; 588} 589 590// These are the signals that are blocked while a (non-VM) thread is 591// running Java. Only the VM thread handles these signals. 592sigset_t* os::Bsd::vm_signals() { 593 assert(signal_sets_initialized, "Not initialized"); 594 return &vm_sigs; 595} 596 597// These are signals that are blocked during cond_wait to allow debugger in 598sigset_t* os::Bsd::allowdebug_blocked_signals() { 599 assert(signal_sets_initialized, "Not initialized"); 600 return &allowdebug_blocked_sigs; 601} 602 603void os::Bsd::hotspot_sigmask(Thread* thread) { 604 605 //Save caller's signal mask before setting VM signal mask 606 sigset_t caller_sigmask; 607 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 608 609 OSThread* osthread = thread->osthread(); 610 osthread->set_caller_sigmask(caller_sigmask); 611 612 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 613 614 if (!ReduceSignalUsage) { 615 if (thread->is_VM_thread()) { 616 // Only the VM thread handles BREAK_SIGNAL ... 617 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 618 } else { 619 // ... all other threads block BREAK_SIGNAL 620 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 621 } 622 } 623} 624 625 626////////////////////////////////////////////////////////////////////////////// 627// create new thread 628 629// check if it's safe to start a new thread 630static bool _thread_safety_check(Thread* thread) { 631 return true; 632} 633 634#ifdef __APPLE__ 635// library handle for calling objc_registerThreadWithCollector() 636// without static linking to the libobjc library 637#define OBJC_LIB "/usr/lib/libobjc.dylib" 638#define OBJC_GCREGISTER "objc_registerThreadWithCollector" 639typedef void (*objc_registerThreadWithCollector_t)(); 640extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 641objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 642#endif 643 644#ifdef __APPLE__ 645static uint64_t locate_unique_thread_id() { 646 // Additional thread_id used to correlate threads in SA 647 thread_identifier_info_data_t m_ident_info; 648 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 649 650 thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO, 651 (thread_info_t) &m_ident_info, &count); 652 return m_ident_info.thread_id; 653} 654#endif 655 656// Thread start routine for all newly created threads 657static void *java_start(Thread *thread) { 658 // Try to randomize the cache line index of hot stack frames. 659 // This helps when threads of the same stack traces evict each other's 660 // cache lines. The threads can be either from the same JVM instance, or 661 // from different JVM instances. The benefit is especially true for 662 // processors with hyperthreading technology. 663 static int counter = 0; 664 int pid = os::current_process_id(); 665 alloca(((pid ^ counter++) & 7) * 128); 666 667 ThreadLocalStorage::set_thread(thread); 668 669 OSThread* osthread = thread->osthread(); 670 Monitor* sync = osthread->startThread_lock(); 671 672 // non floating stack BsdThreads needs extra check, see above 673 if (!_thread_safety_check(thread)) { 674 // notify parent thread 675 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 676 osthread->set_state(ZOMBIE); 677 sync->notify_all(); 678 return NULL; 679 } 680 681#ifdef __APPLE__ 682 // thread_id is mach thread on macos 683 osthread->set_thread_id(::mach_thread_self()); 684 osthread->set_unique_thread_id(locate_unique_thread_id()); 685#else 686 // thread_id is pthread_id on BSD 687 osthread->set_thread_id(::pthread_self()); 688#endif 689 // initialize signal mask for this thread 690 os::Bsd::hotspot_sigmask(thread); 691 692 // initialize floating point control register 693 os::Bsd::init_thread_fpu_state(); 694 695#ifdef __APPLE__ 696 // register thread with objc gc 697 if (objc_registerThreadWithCollectorFunction != NULL) { 698 objc_registerThreadWithCollectorFunction(); 699 } 700#endif 701 702 // handshaking with parent thread 703 { 704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 705 706 // notify parent thread 707 osthread->set_state(INITIALIZED); 708 sync->notify_all(); 709 710 // wait until os::start_thread() 711 while (osthread->get_state() == INITIALIZED) { 712 sync->wait(Mutex::_no_safepoint_check_flag); 713 } 714 } 715 716 // call one more level start routine 717 thread->run(); 718 719 return 0; 720} 721 722bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 723 assert(thread->osthread() == NULL, "caller responsible"); 724 725 // Allocate the OSThread object 726 OSThread* osthread = new OSThread(NULL, NULL); 727 if (osthread == NULL) { 728 return false; 729 } 730 731 // set the correct thread state 732 osthread->set_thread_type(thr_type); 733 734 // Initial state is ALLOCATED but not INITIALIZED 735 osthread->set_state(ALLOCATED); 736 737 thread->set_osthread(osthread); 738 739 // init thread attributes 740 pthread_attr_t attr; 741 pthread_attr_init(&attr); 742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 743 744 // stack size 745 if (os::Bsd::supports_variable_stack_size()) { 746 // calculate stack size if it's not specified by caller 747 if (stack_size == 0) { 748 stack_size = os::Bsd::default_stack_size(thr_type); 749 750 switch (thr_type) { 751 case os::java_thread: 752 // Java threads use ThreadStackSize which default value can be 753 // changed with the flag -Xss 754 assert (JavaThread::stack_size_at_create() > 0, "this should be set"); 755 stack_size = JavaThread::stack_size_at_create(); 756 break; 757 case os::compiler_thread: 758 if (CompilerThreadStackSize > 0) { 759 stack_size = (size_t)(CompilerThreadStackSize * K); 760 break; 761 } // else fall through: 762 // use VMThreadStackSize if CompilerThreadStackSize is not defined 763 case os::vm_thread: 764 case os::pgc_thread: 765 case os::cgc_thread: 766 case os::watcher_thread: 767 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 768 break; 769 } 770 } 771 772 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 773 pthread_attr_setstacksize(&attr, stack_size); 774 } else { 775 // let pthread_create() pick the default value. 776 } 777 778 ThreadState state; 779 780 { 781 pthread_t tid; 782 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 783 784 pthread_attr_destroy(&attr); 785 786 if (ret != 0) { 787 if (PrintMiscellaneous && (Verbose || WizardMode)) { 788 perror("pthread_create()"); 789 } 790 // Need to clean up stuff we've allocated so far 791 thread->set_osthread(NULL); 792 delete osthread; 793 return false; 794 } 795 796 // Store pthread info into the OSThread 797 osthread->set_pthread_id(tid); 798 799 // Wait until child thread is either initialized or aborted 800 { 801 Monitor* sync_with_child = osthread->startThread_lock(); 802 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 803 while ((state = osthread->get_state()) == ALLOCATED) { 804 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 805 } 806 } 807 808 } 809 810 // Aborted due to thread limit being reached 811 if (state == ZOMBIE) { 812 thread->set_osthread(NULL); 813 delete osthread; 814 return false; 815 } 816 817 // The thread is returned suspended (in state INITIALIZED), 818 // and is started higher up in the call chain 819 assert(state == INITIALIZED, "race condition"); 820 return true; 821} 822 823///////////////////////////////////////////////////////////////////////////// 824// attach existing thread 825 826// bootstrap the main thread 827bool os::create_main_thread(JavaThread* thread) { 828 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 829 return create_attached_thread(thread); 830} 831 832bool os::create_attached_thread(JavaThread* thread) { 833#ifdef ASSERT 834 thread->verify_not_published(); 835#endif 836 837 // Allocate the OSThread object 838 OSThread* osthread = new OSThread(NULL, NULL); 839 840 if (osthread == NULL) { 841 return false; 842 } 843 844 // Store pthread info into the OSThread 845#ifdef __APPLE__ 846 osthread->set_thread_id(::mach_thread_self()); 847 osthread->set_unique_thread_id(locate_unique_thread_id()); 848#else 849 osthread->set_thread_id(::pthread_self()); 850#endif 851 osthread->set_pthread_id(::pthread_self()); 852 853 // initialize floating point control register 854 os::Bsd::init_thread_fpu_state(); 855 856 // Initial thread state is RUNNABLE 857 osthread->set_state(RUNNABLE); 858 859 thread->set_osthread(osthread); 860 861 // initialize signal mask for this thread 862 // and save the caller's signal mask 863 os::Bsd::hotspot_sigmask(thread); 864 865 return true; 866} 867 868void os::pd_start_thread(Thread* thread) { 869 OSThread * osthread = thread->osthread(); 870 assert(osthread->get_state() != INITIALIZED, "just checking"); 871 Monitor* sync_with_child = osthread->startThread_lock(); 872 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 873 sync_with_child->notify(); 874} 875 876// Free Bsd resources related to the OSThread 877void os::free_thread(OSThread* osthread) { 878 assert(osthread != NULL, "osthread not set"); 879 880 if (Thread::current()->osthread() == osthread) { 881 // Restore caller's signal mask 882 sigset_t sigmask = osthread->caller_sigmask(); 883 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 884 } 885 886 delete osthread; 887} 888 889////////////////////////////////////////////////////////////////////////////// 890// thread local storage 891 892int os::allocate_thread_local_storage() { 893 pthread_key_t key; 894 int rslt = pthread_key_create(&key, NULL); 895 assert(rslt == 0, "cannot allocate thread local storage"); 896 return (int)key; 897} 898 899// Note: This is currently not used by VM, as we don't destroy TLS key 900// on VM exit. 901void os::free_thread_local_storage(int index) { 902 int rslt = pthread_key_delete((pthread_key_t)index); 903 assert(rslt == 0, "invalid index"); 904} 905 906void os::thread_local_storage_at_put(int index, void* value) { 907 int rslt = pthread_setspecific((pthread_key_t)index, value); 908 assert(rslt == 0, "pthread_setspecific failed"); 909} 910 911extern "C" Thread* get_thread() { 912 return ThreadLocalStorage::thread(); 913} 914 915 916//////////////////////////////////////////////////////////////////////////////// 917// time support 918 919// Time since start-up in seconds to a fine granularity. 920// Used by VMSelfDestructTimer and the MemProfiler. 921double os::elapsedTime() { 922 923 return (double)(os::elapsed_counter()) * 0.000001; 924} 925 926jlong os::elapsed_counter() { 927 timeval time; 928 int status = gettimeofday(&time, NULL); 929 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count; 930} 931 932jlong os::elapsed_frequency() { 933 return (1000 * 1000); 934} 935 936bool os::supports_vtime() { return true; } 937bool os::enable_vtime() { return false; } 938bool os::vtime_enabled() { return false; } 939 940double os::elapsedVTime() { 941 // better than nothing, but not much 942 return elapsedTime(); 943} 944 945jlong os::javaTimeMillis() { 946 timeval time; 947 int status = gettimeofday(&time, NULL); 948 assert(status != -1, "bsd error"); 949 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 950} 951 952#ifndef CLOCK_MONOTONIC 953#define CLOCK_MONOTONIC (1) 954#endif 955 956#ifdef __APPLE__ 957void os::Bsd::clock_init() { 958 // XXXDARWIN: Investigate replacement monotonic clock 959} 960#else 961void os::Bsd::clock_init() { 962 struct timespec res; 963 struct timespec tp; 964 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 965 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 966 // yes, monotonic clock is supported 967 _clock_gettime = ::clock_gettime; 968 } 969} 970#endif 971 972 973jlong os::javaTimeNanos() { 974 if (Bsd::supports_monotonic_clock()) { 975 struct timespec tp; 976 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp); 977 assert(status == 0, "gettime error"); 978 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 979 return result; 980 } else { 981 timeval time; 982 int status = gettimeofday(&time, NULL); 983 assert(status != -1, "bsd error"); 984 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 985 return 1000 * usecs; 986 } 987} 988 989void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 990 if (Bsd::supports_monotonic_clock()) { 991 info_ptr->max_value = ALL_64_BITS; 992 993 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 994 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 995 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 996 } else { 997 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 998 info_ptr->max_value = ALL_64_BITS; 999 1000 // gettimeofday is a real time clock so it skips 1001 info_ptr->may_skip_backward = true; 1002 info_ptr->may_skip_forward = true; 1003 } 1004 1005 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1006} 1007 1008// Return the real, user, and system times in seconds from an 1009// arbitrary fixed point in the past. 1010bool os::getTimesSecs(double* process_real_time, 1011 double* process_user_time, 1012 double* process_system_time) { 1013 struct tms ticks; 1014 clock_t real_ticks = times(&ticks); 1015 1016 if (real_ticks == (clock_t) (-1)) { 1017 return false; 1018 } else { 1019 double ticks_per_second = (double) clock_tics_per_sec; 1020 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1021 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1022 *process_real_time = ((double) real_ticks) / ticks_per_second; 1023 1024 return true; 1025 } 1026} 1027 1028 1029char * os::local_time_string(char *buf, size_t buflen) { 1030 struct tm t; 1031 time_t long_time; 1032 time(&long_time); 1033 localtime_r(&long_time, &t); 1034 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1035 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1036 t.tm_hour, t.tm_min, t.tm_sec); 1037 return buf; 1038} 1039 1040struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1041 return localtime_r(clock, res); 1042} 1043 1044//////////////////////////////////////////////////////////////////////////////// 1045// runtime exit support 1046 1047// Note: os::shutdown() might be called very early during initialization, or 1048// called from signal handler. Before adding something to os::shutdown(), make 1049// sure it is async-safe and can handle partially initialized VM. 1050void os::shutdown() { 1051 1052 // allow PerfMemory to attempt cleanup of any persistent resources 1053 perfMemory_exit(); 1054 1055 // needs to remove object in file system 1056 AttachListener::abort(); 1057 1058 // flush buffered output, finish log files 1059 ostream_abort(); 1060 1061 // Check for abort hook 1062 abort_hook_t abort_hook = Arguments::abort_hook(); 1063 if (abort_hook != NULL) { 1064 abort_hook(); 1065 } 1066 1067} 1068 1069// Note: os::abort() might be called very early during initialization, or 1070// called from signal handler. Before adding something to os::abort(), make 1071// sure it is async-safe and can handle partially initialized VM. 1072void os::abort(bool dump_core) { 1073 os::shutdown(); 1074 if (dump_core) { 1075#ifndef PRODUCT 1076 fdStream out(defaultStream::output_fd()); 1077 out.print_raw("Current thread is "); 1078 char buf[16]; 1079 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1080 out.print_raw_cr(buf); 1081 out.print_raw_cr("Dumping core ..."); 1082#endif 1083 ::abort(); // dump core 1084 } 1085 1086 ::exit(1); 1087} 1088 1089// Die immediately, no exit hook, no abort hook, no cleanup. 1090void os::die() { 1091 // _exit() on BsdThreads only kills current thread 1092 ::abort(); 1093} 1094 1095// unused on bsd for now. 1096void os::set_error_file(const char *logfile) {} 1097 1098 1099// This method is a copy of JDK's sysGetLastErrorString 1100// from src/solaris/hpi/src/system_md.c 1101 1102size_t os::lasterror(char *buf, size_t len) { 1103 1104 if (errno == 0) return 0; 1105 1106 const char *s = ::strerror(errno); 1107 size_t n = ::strlen(s); 1108 if (n >= len) { 1109 n = len - 1; 1110 } 1111 ::strncpy(buf, s, n); 1112 buf[n] = '\0'; 1113 return n; 1114} 1115 1116intx os::current_thread_id() { 1117#ifdef __APPLE__ 1118 return (intx)::mach_thread_self(); 1119#else 1120 return (intx)::pthread_self(); 1121#endif 1122} 1123int os::current_process_id() { 1124 1125 // Under the old bsd thread library, bsd gives each thread 1126 // its own process id. Because of this each thread will return 1127 // a different pid if this method were to return the result 1128 // of getpid(2). Bsd provides no api that returns the pid 1129 // of the launcher thread for the vm. This implementation 1130 // returns a unique pid, the pid of the launcher thread 1131 // that starts the vm 'process'. 1132 1133 // Under the NPTL, getpid() returns the same pid as the 1134 // launcher thread rather than a unique pid per thread. 1135 // Use gettid() if you want the old pre NPTL behaviour. 1136 1137 // if you are looking for the result of a call to getpid() that 1138 // returns a unique pid for the calling thread, then look at the 1139 // OSThread::thread_id() method in osThread_bsd.hpp file 1140 1141 return (int)(_initial_pid ? _initial_pid : getpid()); 1142} 1143 1144// DLL functions 1145 1146#define JNI_LIB_PREFIX "lib" 1147#ifdef __APPLE__ 1148#define JNI_LIB_SUFFIX ".dylib" 1149#else 1150#define JNI_LIB_SUFFIX ".so" 1151#endif 1152 1153const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1154 1155// This must be hard coded because it's the system's temporary 1156// directory not the java application's temp directory, ala java.io.tmpdir. 1157#ifdef __APPLE__ 1158// macosx has a secure per-user temporary directory 1159char temp_path_storage[PATH_MAX]; 1160const char* os::get_temp_directory() { 1161 static char *temp_path = NULL; 1162 if (temp_path == NULL) { 1163 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1164 if (pathSize == 0 || pathSize > PATH_MAX) { 1165 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1166 } 1167 temp_path = temp_path_storage; 1168 } 1169 return temp_path; 1170} 1171#else /* __APPLE__ */ 1172const char* os::get_temp_directory() { return "/tmp"; } 1173#endif /* __APPLE__ */ 1174 1175static bool file_exists(const char* filename) { 1176 struct stat statbuf; 1177 if (filename == NULL || strlen(filename) == 0) { 1178 return false; 1179 } 1180 return os::stat(filename, &statbuf) == 0; 1181} 1182 1183bool os::dll_build_name(char* buffer, size_t buflen, 1184 const char* pname, const char* fname) { 1185 bool retval = false; 1186 // Copied from libhpi 1187 const size_t pnamelen = pname ? strlen(pname) : 0; 1188 1189 // Return error on buffer overflow. 1190 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1191 return retval; 1192 } 1193 1194 if (pnamelen == 0) { 1195 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1196 retval = true; 1197 } else if (strchr(pname, *os::path_separator()) != NULL) { 1198 int n; 1199 char** pelements = split_path(pname, &n); 1200 if (pelements == NULL) { 1201 return false; 1202 } 1203 for (int i = 0 ; i < n ; i++) { 1204 // Really shouldn't be NULL, but check can't hurt 1205 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1206 continue; // skip the empty path values 1207 } 1208 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1209 pelements[i], fname); 1210 if (file_exists(buffer)) { 1211 retval = true; 1212 break; 1213 } 1214 } 1215 // release the storage 1216 for (int i = 0 ; i < n ; i++) { 1217 if (pelements[i] != NULL) { 1218 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1219 } 1220 } 1221 if (pelements != NULL) { 1222 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1223 } 1224 } else { 1225 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1226 retval = true; 1227 } 1228 return retval; 1229} 1230 1231// check if addr is inside libjvm.so 1232bool os::address_is_in_vm(address addr) { 1233 static address libjvm_base_addr; 1234 Dl_info dlinfo; 1235 1236 if (libjvm_base_addr == NULL) { 1237 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo); 1238 libjvm_base_addr = (address)dlinfo.dli_fbase; 1239 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1240 } 1241 1242 if (dladdr((void *)addr, &dlinfo)) { 1243 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1244 } 1245 1246 return false; 1247} 1248 1249 1250#define MACH_MAXSYMLEN 256 1251 1252bool os::dll_address_to_function_name(address addr, char *buf, 1253 int buflen, int *offset) { 1254 Dl_info dlinfo; 1255 char localbuf[MACH_MAXSYMLEN]; 1256 1257 // dladdr will find names of dynamic functions only, but does 1258 // it set dli_fbase with mach_header address when it "fails" ? 1259 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) { 1260 if (buf != NULL) { 1261 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1262 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1263 } 1264 } 1265 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1266 return true; 1267 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) { 1268 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1269 buf, buflen, offset, dlinfo.dli_fname)) { 1270 return true; 1271 } 1272 } 1273 1274 // Handle non-dymanic manually: 1275 if (dlinfo.dli_fbase != NULL && 1276 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) { 1277 if(!Decoder::demangle(localbuf, buf, buflen)) { 1278 jio_snprintf(buf, buflen, "%s", localbuf); 1279 } 1280 return true; 1281 } 1282 if (buf != NULL) buf[0] = '\0'; 1283 if (offset != NULL) *offset = -1; 1284 return false; 1285} 1286 1287// ported from solaris version 1288bool os::dll_address_to_library_name(address addr, char* buf, 1289 int buflen, int* offset) { 1290 Dl_info dlinfo; 1291 1292 if (dladdr((void*)addr, &dlinfo)){ 1293 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1294 if (offset) *offset = addr - (address)dlinfo.dli_fbase; 1295 return true; 1296 } else { 1297 if (buf) buf[0] = '\0'; 1298 if (offset) *offset = -1; 1299 return false; 1300 } 1301} 1302 1303// Loads .dll/.so and 1304// in case of error it checks if .dll/.so was built for the 1305// same architecture as Hotspot is running on 1306 1307#ifdef __APPLE__ 1308void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1309 void * result= ::dlopen(filename, RTLD_LAZY); 1310 if (result != NULL) { 1311 // Successful loading 1312 return result; 1313 } 1314 1315 // Read system error message into ebuf 1316 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1317 ebuf[ebuflen-1]='\0'; 1318 1319 return NULL; 1320} 1321#else 1322void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1323{ 1324 void * result= ::dlopen(filename, RTLD_LAZY); 1325 if (result != NULL) { 1326 // Successful loading 1327 return result; 1328 } 1329 1330 Elf32_Ehdr elf_head; 1331 1332 // Read system error message into ebuf 1333 // It may or may not be overwritten below 1334 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1335 ebuf[ebuflen-1]='\0'; 1336 int diag_msg_max_length=ebuflen-strlen(ebuf); 1337 char* diag_msg_buf=ebuf+strlen(ebuf); 1338 1339 if (diag_msg_max_length==0) { 1340 // No more space in ebuf for additional diagnostics message 1341 return NULL; 1342 } 1343 1344 1345 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1346 1347 if (file_descriptor < 0) { 1348 // Can't open library, report dlerror() message 1349 return NULL; 1350 } 1351 1352 bool failed_to_read_elf_head= 1353 (sizeof(elf_head)!= 1354 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 1355 1356 ::close(file_descriptor); 1357 if (failed_to_read_elf_head) { 1358 // file i/o error - report dlerror() msg 1359 return NULL; 1360 } 1361 1362 typedef struct { 1363 Elf32_Half code; // Actual value as defined in elf.h 1364 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1365 char elf_class; // 32 or 64 bit 1366 char endianess; // MSB or LSB 1367 char* name; // String representation 1368 } arch_t; 1369 1370 #ifndef EM_486 1371 #define EM_486 6 /* Intel 80486 */ 1372 #endif 1373 1374 #ifndef EM_MIPS_RS3_LE 1375 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1376 #endif 1377 1378 #ifndef EM_PPC64 1379 #define EM_PPC64 21 /* PowerPC64 */ 1380 #endif 1381 1382 #ifndef EM_S390 1383 #define EM_S390 22 /* IBM System/390 */ 1384 #endif 1385 1386 #ifndef EM_IA_64 1387 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1388 #endif 1389 1390 #ifndef EM_X86_64 1391 #define EM_X86_64 62 /* AMD x86-64 */ 1392 #endif 1393 1394 static const arch_t arch_array[]={ 1395 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1396 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1397 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1398 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1399 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1400 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1401 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1402 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1403 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1404 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1405 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1406 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1407 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1408 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1409 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1410 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1411 }; 1412 1413 #if (defined IA32) 1414 static Elf32_Half running_arch_code=EM_386; 1415 #elif (defined AMD64) 1416 static Elf32_Half running_arch_code=EM_X86_64; 1417 #elif (defined IA64) 1418 static Elf32_Half running_arch_code=EM_IA_64; 1419 #elif (defined __sparc) && (defined _LP64) 1420 static Elf32_Half running_arch_code=EM_SPARCV9; 1421 #elif (defined __sparc) && (!defined _LP64) 1422 static Elf32_Half running_arch_code=EM_SPARC; 1423 #elif (defined __powerpc64__) 1424 static Elf32_Half running_arch_code=EM_PPC64; 1425 #elif (defined __powerpc__) 1426 static Elf32_Half running_arch_code=EM_PPC; 1427 #elif (defined ARM) 1428 static Elf32_Half running_arch_code=EM_ARM; 1429 #elif (defined S390) 1430 static Elf32_Half running_arch_code=EM_S390; 1431 #elif (defined ALPHA) 1432 static Elf32_Half running_arch_code=EM_ALPHA; 1433 #elif (defined MIPSEL) 1434 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1435 #elif (defined PARISC) 1436 static Elf32_Half running_arch_code=EM_PARISC; 1437 #elif (defined MIPS) 1438 static Elf32_Half running_arch_code=EM_MIPS; 1439 #elif (defined M68K) 1440 static Elf32_Half running_arch_code=EM_68K; 1441 #else 1442 #error Method os::dll_load requires that one of following is defined:\ 1443 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1444 #endif 1445 1446 // Identify compatability class for VM's architecture and library's architecture 1447 // Obtain string descriptions for architectures 1448 1449 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1450 int running_arch_index=-1; 1451 1452 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 1453 if (running_arch_code == arch_array[i].code) { 1454 running_arch_index = i; 1455 } 1456 if (lib_arch.code == arch_array[i].code) { 1457 lib_arch.compat_class = arch_array[i].compat_class; 1458 lib_arch.name = arch_array[i].name; 1459 } 1460 } 1461 1462 assert(running_arch_index != -1, 1463 "Didn't find running architecture code (running_arch_code) in arch_array"); 1464 if (running_arch_index == -1) { 1465 // Even though running architecture detection failed 1466 // we may still continue with reporting dlerror() message 1467 return NULL; 1468 } 1469 1470 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1471 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1472 return NULL; 1473 } 1474 1475#ifndef S390 1476 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1477 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1478 return NULL; 1479 } 1480#endif // !S390 1481 1482 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1483 if ( lib_arch.name!=NULL ) { 1484 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1485 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1486 lib_arch.name, arch_array[running_arch_index].name); 1487 } else { 1488 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1489 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1490 lib_arch.code, 1491 arch_array[running_arch_index].name); 1492 } 1493 } 1494 1495 return NULL; 1496} 1497#endif /* !__APPLE__ */ 1498 1499// XXX: Do we need a lock around this as per Linux? 1500void* os::dll_lookup(void* handle, const char* name) { 1501 return dlsym(handle, name); 1502} 1503 1504 1505static bool _print_ascii_file(const char* filename, outputStream* st) { 1506 int fd = ::open(filename, O_RDONLY); 1507 if (fd == -1) { 1508 return false; 1509 } 1510 1511 char buf[32]; 1512 int bytes; 1513 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1514 st->print_raw(buf, bytes); 1515 } 1516 1517 ::close(fd); 1518 1519 return true; 1520} 1521 1522void os::print_dll_info(outputStream *st) { 1523 st->print_cr("Dynamic libraries:"); 1524#ifdef RTLD_DI_LINKMAP 1525 Dl_info dli; 1526 void *handle; 1527 Link_map *map; 1528 Link_map *p; 1529 1530 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) { 1531 st->print_cr("Error: Cannot print dynamic libraries."); 1532 return; 1533 } 1534 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1535 if (handle == NULL) { 1536 st->print_cr("Error: Cannot print dynamic libraries."); 1537 return; 1538 } 1539 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1540 if (map == NULL) { 1541 st->print_cr("Error: Cannot print dynamic libraries."); 1542 return; 1543 } 1544 1545 while (map->l_prev != NULL) 1546 map = map->l_prev; 1547 1548 while (map != NULL) { 1549 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1550 map = map->l_next; 1551 } 1552 1553 dlclose(handle); 1554#elif defined(__APPLE__) 1555 uint32_t count; 1556 uint32_t i; 1557 1558 count = _dyld_image_count(); 1559 for (i = 1; i < count; i++) { 1560 const char *name = _dyld_get_image_name(i); 1561 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 1562 st->print_cr(PTR_FORMAT " \t%s", slide, name); 1563 } 1564#else 1565 st->print_cr("Error: Cannot print dynamic libraries."); 1566#endif 1567} 1568 1569void os::print_os_info_brief(outputStream* st) { 1570 st->print("Bsd"); 1571 1572 os::Posix::print_uname_info(st); 1573} 1574 1575void os::print_os_info(outputStream* st) { 1576 st->print("OS:"); 1577 st->print("Bsd"); 1578 1579 os::Posix::print_uname_info(st); 1580 1581 os::Posix::print_rlimit_info(st); 1582 1583 os::Posix::print_load_average(st); 1584} 1585 1586void os::pd_print_cpu_info(outputStream* st) { 1587 // Nothing to do for now. 1588} 1589 1590void os::print_memory_info(outputStream* st) { 1591 1592 st->print("Memory:"); 1593 st->print(" %dk page", os::vm_page_size()>>10); 1594 1595 st->print(", physical " UINT64_FORMAT "k", 1596 os::physical_memory() >> 10); 1597 st->print("(" UINT64_FORMAT "k free)", 1598 os::available_memory() >> 10); 1599 st->cr(); 1600 1601 // meminfo 1602 st->print("\n/proc/meminfo:\n"); 1603 _print_ascii_file("/proc/meminfo", st); 1604 st->cr(); 1605} 1606 1607// Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific 1608// but they're the same for all the bsd arch that we support 1609// and they're the same for solaris but there's no common place to put this. 1610const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR", 1611 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG", 1612 "ILL_COPROC", "ILL_BADSTK" }; 1613 1614const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV", 1615 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES", 1616 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" }; 1617 1618const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" }; 1619 1620const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" }; 1621 1622void os::print_siginfo(outputStream* st, void* siginfo) { 1623 st->print("siginfo:"); 1624 1625 const int buflen = 100; 1626 char buf[buflen]; 1627 siginfo_t *si = (siginfo_t*)siginfo; 1628 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen)); 1629 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) { 1630 st->print("si_errno=%s", buf); 1631 } else { 1632 st->print("si_errno=%d", si->si_errno); 1633 } 1634 const int c = si->si_code; 1635 assert(c > 0, "unexpected si_code"); 1636 switch (si->si_signo) { 1637 case SIGILL: 1638 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]); 1639 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1640 break; 1641 case SIGFPE: 1642 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]); 1643 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1644 break; 1645 case SIGSEGV: 1646 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]); 1647 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1648 break; 1649 case SIGBUS: 1650 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]); 1651 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1652 break; 1653 default: 1654 st->print(", si_code=%d", si->si_code); 1655 // no si_addr 1656 } 1657 1658 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1659 UseSharedSpaces) { 1660 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1661 if (mapinfo->is_in_shared_space(si->si_addr)) { 1662 st->print("\n\nError accessing class data sharing archive." \ 1663 " Mapped file inaccessible during execution, " \ 1664 " possible disk/network problem."); 1665 } 1666 } 1667 st->cr(); 1668} 1669 1670 1671static void print_signal_handler(outputStream* st, int sig, 1672 char* buf, size_t buflen); 1673 1674void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1675 st->print_cr("Signal Handlers:"); 1676 print_signal_handler(st, SIGSEGV, buf, buflen); 1677 print_signal_handler(st, SIGBUS , buf, buflen); 1678 print_signal_handler(st, SIGFPE , buf, buflen); 1679 print_signal_handler(st, SIGPIPE, buf, buflen); 1680 print_signal_handler(st, SIGXFSZ, buf, buflen); 1681 print_signal_handler(st, SIGILL , buf, buflen); 1682 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1683 print_signal_handler(st, SR_signum, buf, buflen); 1684 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1685 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1686 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1687 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1688} 1689 1690static char saved_jvm_path[MAXPATHLEN] = {0}; 1691 1692// Find the full path to the current module, libjvm 1693void os::jvm_path(char *buf, jint buflen) { 1694 // Error checking. 1695 if (buflen < MAXPATHLEN) { 1696 assert(false, "must use a large-enough buffer"); 1697 buf[0] = '\0'; 1698 return; 1699 } 1700 // Lazy resolve the path to current module. 1701 if (saved_jvm_path[0] != 0) { 1702 strcpy(buf, saved_jvm_path); 1703 return; 1704 } 1705 1706 char dli_fname[MAXPATHLEN]; 1707 bool ret = dll_address_to_library_name( 1708 CAST_FROM_FN_PTR(address, os::jvm_path), 1709 dli_fname, sizeof(dli_fname), NULL); 1710 assert(ret != 0, "cannot locate libjvm"); 1711 char *rp = realpath(dli_fname, buf); 1712 if (rp == NULL) 1713 return; 1714 1715 if (Arguments::created_by_gamma_launcher()) { 1716 // Support for the gamma launcher. Typical value for buf is 1717 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at 1718 // the right place in the string, then assume we are installed in a JDK and 1719 // we're done. Otherwise, check for a JAVA_HOME environment variable and 1720 // construct a path to the JVM being overridden. 1721 1722 const char *p = buf + strlen(buf) - 1; 1723 for (int count = 0; p > buf && count < 5; ++count) { 1724 for (--p; p > buf && *p != '/'; --p) 1725 /* empty */ ; 1726 } 1727 1728 if (strncmp(p, "/jre/lib/", 9) != 0) { 1729 // Look for JAVA_HOME in the environment. 1730 char* java_home_var = ::getenv("JAVA_HOME"); 1731 if (java_home_var != NULL && java_home_var[0] != 0) { 1732 char* jrelib_p; 1733 int len; 1734 1735 // Check the current module name "libjvm" 1736 p = strrchr(buf, '/'); 1737 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1738 1739 rp = realpath(java_home_var, buf); 1740 if (rp == NULL) 1741 return; 1742 1743 // determine if this is a legacy image or modules image 1744 // modules image doesn't have "jre" subdirectory 1745 len = strlen(buf); 1746 jrelib_p = buf + len; 1747 1748 // Add the appropriate library subdir 1749 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1750 if (0 != access(buf, F_OK)) { 1751 snprintf(jrelib_p, buflen-len, "/lib"); 1752 } 1753 1754 // Add the appropriate client or server subdir 1755 len = strlen(buf); 1756 jrelib_p = buf + len; 1757 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1758 if (0 != access(buf, F_OK)) { 1759 snprintf(jrelib_p, buflen-len, ""); 1760 } 1761 1762 // If the path exists within JAVA_HOME, add the JVM library name 1763 // to complete the path to JVM being overridden. Otherwise fallback 1764 // to the path to the current library. 1765 if (0 == access(buf, F_OK)) { 1766 // Use current module name "libjvm" 1767 len = strlen(buf); 1768 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1769 } else { 1770 // Fall back to path of current library 1771 rp = realpath(dli_fname, buf); 1772 if (rp == NULL) 1773 return; 1774 } 1775 } 1776 } 1777 } 1778 1779 strcpy(saved_jvm_path, buf); 1780} 1781 1782void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1783 // no prefix required, not even "_" 1784} 1785 1786void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1787 // no suffix required 1788} 1789 1790//////////////////////////////////////////////////////////////////////////////// 1791// sun.misc.Signal support 1792 1793static volatile jint sigint_count = 0; 1794 1795static void 1796UserHandler(int sig, void *siginfo, void *context) { 1797 // 4511530 - sem_post is serialized and handled by the manager thread. When 1798 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1799 // don't want to flood the manager thread with sem_post requests. 1800 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1801 return; 1802 1803 // Ctrl-C is pressed during error reporting, likely because the error 1804 // handler fails to abort. Let VM die immediately. 1805 if (sig == SIGINT && is_error_reported()) { 1806 os::die(); 1807 } 1808 1809 os::signal_notify(sig); 1810} 1811 1812void* os::user_handler() { 1813 return CAST_FROM_FN_PTR(void*, UserHandler); 1814} 1815 1816extern "C" { 1817 typedef void (*sa_handler_t)(int); 1818 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1819} 1820 1821void* os::signal(int signal_number, void* handler) { 1822 struct sigaction sigAct, oldSigAct; 1823 1824 sigfillset(&(sigAct.sa_mask)); 1825 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1826 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1827 1828 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1829 // -1 means registration failed 1830 return (void *)-1; 1831 } 1832 1833 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1834} 1835 1836void os::signal_raise(int signal_number) { 1837 ::raise(signal_number); 1838} 1839 1840/* 1841 * The following code is moved from os.cpp for making this 1842 * code platform specific, which it is by its very nature. 1843 */ 1844 1845// Will be modified when max signal is changed to be dynamic 1846int os::sigexitnum_pd() { 1847 return NSIG; 1848} 1849 1850// a counter for each possible signal value 1851static volatile jint pending_signals[NSIG+1] = { 0 }; 1852 1853// Bsd(POSIX) specific hand shaking semaphore. 1854#ifdef __APPLE__ 1855typedef semaphore_t os_semaphore_t; 1856#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1857#define SEM_WAIT(sem) semaphore_wait(sem) 1858#define SEM_POST(sem) semaphore_signal(sem) 1859#define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1860#else 1861typedef sem_t os_semaphore_t; 1862#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1863#define SEM_WAIT(sem) sem_wait(&sem) 1864#define SEM_POST(sem) sem_post(&sem) 1865#define SEM_DESTROY(sem) sem_destroy(&sem) 1866#endif 1867 1868class Semaphore : public StackObj { 1869 public: 1870 Semaphore(); 1871 ~Semaphore(); 1872 void signal(); 1873 void wait(); 1874 bool trywait(); 1875 bool timedwait(unsigned int sec, int nsec); 1876 private: 1877 jlong currenttime() const; 1878 semaphore_t _semaphore; 1879}; 1880 1881Semaphore::Semaphore() : _semaphore(0) { 1882 SEM_INIT(_semaphore, 0); 1883} 1884 1885Semaphore::~Semaphore() { 1886 SEM_DESTROY(_semaphore); 1887} 1888 1889void Semaphore::signal() { 1890 SEM_POST(_semaphore); 1891} 1892 1893void Semaphore::wait() { 1894 SEM_WAIT(_semaphore); 1895} 1896 1897jlong Semaphore::currenttime() const { 1898 struct timeval tv; 1899 gettimeofday(&tv, NULL); 1900 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1901} 1902 1903#ifdef __APPLE__ 1904bool Semaphore::trywait() { 1905 return timedwait(0, 0); 1906} 1907 1908bool Semaphore::timedwait(unsigned int sec, int nsec) { 1909 kern_return_t kr = KERN_ABORTED; 1910 mach_timespec_t waitspec; 1911 waitspec.tv_sec = sec; 1912 waitspec.tv_nsec = nsec; 1913 1914 jlong starttime = currenttime(); 1915 1916 kr = semaphore_timedwait(_semaphore, waitspec); 1917 while (kr == KERN_ABORTED) { 1918 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1919 1920 jlong current = currenttime(); 1921 jlong passedtime = current - starttime; 1922 1923 if (passedtime >= totalwait) { 1924 waitspec.tv_sec = 0; 1925 waitspec.tv_nsec = 0; 1926 } else { 1927 jlong waittime = totalwait - (current - starttime); 1928 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 1929 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 1930 } 1931 1932 kr = semaphore_timedwait(_semaphore, waitspec); 1933 } 1934 1935 return kr == KERN_SUCCESS; 1936} 1937 1938#else 1939 1940bool Semaphore::trywait() { 1941 return sem_trywait(&_semaphore) == 0; 1942} 1943 1944bool Semaphore::timedwait(unsigned int sec, int nsec) { 1945 struct timespec ts; 1946 jlong endtime = unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 1947 1948 while (1) { 1949 int result = sem_timedwait(&_semaphore, &ts); 1950 if (result == 0) { 1951 return true; 1952 } else if (errno == EINTR) { 1953 continue; 1954 } else if (errno == ETIMEDOUT) { 1955 return false; 1956 } else { 1957 return false; 1958 } 1959 } 1960} 1961 1962#endif // __APPLE__ 1963 1964static os_semaphore_t sig_sem; 1965static Semaphore sr_semaphore; 1966 1967void os::signal_init_pd() { 1968 // Initialize signal structures 1969 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 1970 1971 // Initialize signal semaphore 1972 ::SEM_INIT(sig_sem, 0); 1973} 1974 1975void os::signal_notify(int sig) { 1976 Atomic::inc(&pending_signals[sig]); 1977 ::SEM_POST(sig_sem); 1978} 1979 1980static int check_pending_signals(bool wait) { 1981 Atomic::store(0, &sigint_count); 1982 for (;;) { 1983 for (int i = 0; i < NSIG + 1; i++) { 1984 jint n = pending_signals[i]; 1985 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 1986 return i; 1987 } 1988 } 1989 if (!wait) { 1990 return -1; 1991 } 1992 JavaThread *thread = JavaThread::current(); 1993 ThreadBlockInVM tbivm(thread); 1994 1995 bool threadIsSuspended; 1996 do { 1997 thread->set_suspend_equivalent(); 1998 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 1999 ::SEM_WAIT(sig_sem); 2000 2001 // were we externally suspended while we were waiting? 2002 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2003 if (threadIsSuspended) { 2004 // 2005 // The semaphore has been incremented, but while we were waiting 2006 // another thread suspended us. We don't want to continue running 2007 // while suspended because that would surprise the thread that 2008 // suspended us. 2009 // 2010 ::SEM_POST(sig_sem); 2011 2012 thread->java_suspend_self(); 2013 } 2014 } while (threadIsSuspended); 2015 } 2016} 2017 2018int os::signal_lookup() { 2019 return check_pending_signals(false); 2020} 2021 2022int os::signal_wait() { 2023 return check_pending_signals(true); 2024} 2025 2026//////////////////////////////////////////////////////////////////////////////// 2027// Virtual Memory 2028 2029int os::vm_page_size() { 2030 // Seems redundant as all get out 2031 assert(os::Bsd::page_size() != -1, "must call os::init"); 2032 return os::Bsd::page_size(); 2033} 2034 2035// Solaris allocates memory by pages. 2036int os::vm_allocation_granularity() { 2037 assert(os::Bsd::page_size() != -1, "must call os::init"); 2038 return os::Bsd::page_size(); 2039} 2040 2041// Rationale behind this function: 2042// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2043// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2044// samples for JITted code. Here we create private executable mapping over the code cache 2045// and then we can use standard (well, almost, as mapping can change) way to provide 2046// info for the reporting script by storing timestamp and location of symbol 2047void bsd_wrap_code(char* base, size_t size) { 2048 static volatile jint cnt = 0; 2049 2050 if (!UseOprofile) { 2051 return; 2052 } 2053 2054 char buf[PATH_MAX + 1]; 2055 int num = Atomic::add(1, &cnt); 2056 2057 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2058 os::get_temp_directory(), os::current_process_id(), num); 2059 unlink(buf); 2060 2061 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2062 2063 if (fd != -1) { 2064 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2065 if (rv != (off_t)-1) { 2066 if (::write(fd, "", 1) == 1) { 2067 mmap(base, size, 2068 PROT_READ|PROT_WRITE|PROT_EXEC, 2069 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2070 } 2071 } 2072 ::close(fd); 2073 unlink(buf); 2074 } 2075} 2076 2077static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2078 int err) { 2079 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2080 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2081 strerror(err), err); 2082} 2083 2084// NOTE: Bsd kernel does not really reserve the pages for us. 2085// All it does is to check if there are enough free pages 2086// left at the time of mmap(). This could be a potential 2087// problem. 2088bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2089 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2090#ifdef __OpenBSD__ 2091 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2092 if (::mprotect(addr, size, prot) == 0) { 2093 return true; 2094 } 2095#else 2096 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2097 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2098 if (res != (uintptr_t) MAP_FAILED) { 2099 return true; 2100 } 2101#endif 2102 2103 // Warn about any commit errors we see in non-product builds just 2104 // in case mmap() doesn't work as described on the man page. 2105 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2106 2107 return false; 2108} 2109 2110bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2111 bool exec) { 2112 // alignment_hint is ignored on this OS 2113 return pd_commit_memory(addr, size, exec); 2114} 2115 2116void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2117 const char* mesg) { 2118 assert(mesg != NULL, "mesg must be specified"); 2119 if (!pd_commit_memory(addr, size, exec)) { 2120 // add extra info in product mode for vm_exit_out_of_memory(): 2121 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2122 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2123 } 2124} 2125 2126void os::pd_commit_memory_or_exit(char* addr, size_t size, 2127 size_t alignment_hint, bool exec, 2128 const char* mesg) { 2129 // alignment_hint is ignored on this OS 2130 pd_commit_memory_or_exit(addr, size, exec, mesg); 2131} 2132 2133void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2134} 2135 2136void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2137 ::madvise(addr, bytes, MADV_DONTNEED); 2138} 2139 2140void os::numa_make_global(char *addr, size_t bytes) { 2141} 2142 2143void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2144} 2145 2146bool os::numa_topology_changed() { return false; } 2147 2148size_t os::numa_get_groups_num() { 2149 return 1; 2150} 2151 2152int os::numa_get_group_id() { 2153 return 0; 2154} 2155 2156size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2157 if (size > 0) { 2158 ids[0] = 0; 2159 return 1; 2160 } 2161 return 0; 2162} 2163 2164bool os::get_page_info(char *start, page_info* info) { 2165 return false; 2166} 2167 2168char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2169 return end; 2170} 2171 2172 2173bool os::pd_uncommit_memory(char* addr, size_t size) { 2174#ifdef __OpenBSD__ 2175 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2176 return ::mprotect(addr, size, PROT_NONE) == 0; 2177#else 2178 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2179 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2180 return res != (uintptr_t) MAP_FAILED; 2181#endif 2182} 2183 2184bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2185 return os::commit_memory(addr, size, !ExecMem); 2186} 2187 2188// If this is a growable mapping, remove the guard pages entirely by 2189// munmap()ping them. If not, just call uncommit_memory(). 2190bool os::remove_stack_guard_pages(char* addr, size_t size) { 2191 return os::uncommit_memory(addr, size); 2192} 2193 2194static address _highest_vm_reserved_address = NULL; 2195 2196// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2197// at 'requested_addr'. If there are existing memory mappings at the same 2198// location, however, they will be overwritten. If 'fixed' is false, 2199// 'requested_addr' is only treated as a hint, the return value may or 2200// may not start from the requested address. Unlike Bsd mmap(), this 2201// function returns NULL to indicate failure. 2202static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2203 char * addr; 2204 int flags; 2205 2206 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2207 if (fixed) { 2208 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2209 flags |= MAP_FIXED; 2210 } 2211 2212 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2213 // touch an uncommitted page. Otherwise, the read/write might 2214 // succeed if we have enough swap space to back the physical page. 2215 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2216 flags, -1, 0); 2217 2218 if (addr != MAP_FAILED) { 2219 // anon_mmap() should only get called during VM initialization, 2220 // don't need lock (actually we can skip locking even it can be called 2221 // from multiple threads, because _highest_vm_reserved_address is just a 2222 // hint about the upper limit of non-stack memory regions.) 2223 if ((address)addr + bytes > _highest_vm_reserved_address) { 2224 _highest_vm_reserved_address = (address)addr + bytes; 2225 } 2226 } 2227 2228 return addr == MAP_FAILED ? NULL : addr; 2229} 2230 2231// Don't update _highest_vm_reserved_address, because there might be memory 2232// regions above addr + size. If so, releasing a memory region only creates 2233// a hole in the address space, it doesn't help prevent heap-stack collision. 2234// 2235static int anon_munmap(char * addr, size_t size) { 2236 return ::munmap(addr, size) == 0; 2237} 2238 2239char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2240 size_t alignment_hint) { 2241 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2242} 2243 2244bool os::pd_release_memory(char* addr, size_t size) { 2245 return anon_munmap(addr, size); 2246} 2247 2248static bool bsd_mprotect(char* addr, size_t size, int prot) { 2249 // Bsd wants the mprotect address argument to be page aligned. 2250 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2251 2252 // According to SUSv3, mprotect() should only be used with mappings 2253 // established by mmap(), and mmap() always maps whole pages. Unaligned 2254 // 'addr' likely indicates problem in the VM (e.g. trying to change 2255 // protection of malloc'ed or statically allocated memory). Check the 2256 // caller if you hit this assert. 2257 assert(addr == bottom, "sanity check"); 2258 2259 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2260 return ::mprotect(bottom, size, prot) == 0; 2261} 2262 2263// Set protections specified 2264bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2265 bool is_committed) { 2266 unsigned int p = 0; 2267 switch (prot) { 2268 case MEM_PROT_NONE: p = PROT_NONE; break; 2269 case MEM_PROT_READ: p = PROT_READ; break; 2270 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2271 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2272 default: 2273 ShouldNotReachHere(); 2274 } 2275 // is_committed is unused. 2276 return bsd_mprotect(addr, bytes, p); 2277} 2278 2279bool os::guard_memory(char* addr, size_t size) { 2280 return bsd_mprotect(addr, size, PROT_NONE); 2281} 2282 2283bool os::unguard_memory(char* addr, size_t size) { 2284 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2285} 2286 2287bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2288 return false; 2289} 2290 2291// Large page support 2292 2293static size_t _large_page_size = 0; 2294 2295void os::large_page_init() { 2296} 2297 2298 2299char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) { 2300 // "exec" is passed in but not used. Creating the shared image for 2301 // the code cache doesn't have an SHM_X executable permission to check. 2302 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2303 2304 key_t key = IPC_PRIVATE; 2305 char *addr; 2306 2307 bool warn_on_failure = UseLargePages && 2308 (!FLAG_IS_DEFAULT(UseLargePages) || 2309 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2310 ); 2311 char msg[128]; 2312 2313 // Create a large shared memory region to attach to based on size. 2314 // Currently, size is the total size of the heap 2315 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2316 if (shmid == -1) { 2317 // Possible reasons for shmget failure: 2318 // 1. shmmax is too small for Java heap. 2319 // > check shmmax value: cat /proc/sys/kernel/shmmax 2320 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2321 // 2. not enough large page memory. 2322 // > check available large pages: cat /proc/meminfo 2323 // > increase amount of large pages: 2324 // echo new_value > /proc/sys/vm/nr_hugepages 2325 // Note 1: different Bsd may use different name for this property, 2326 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2327 // Note 2: it's possible there's enough physical memory available but 2328 // they are so fragmented after a long run that they can't 2329 // coalesce into large pages. Try to reserve large pages when 2330 // the system is still "fresh". 2331 if (warn_on_failure) { 2332 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 2333 warning(msg); 2334 } 2335 return NULL; 2336 } 2337 2338 // attach to the region 2339 addr = (char*)shmat(shmid, req_addr, 0); 2340 int err = errno; 2341 2342 // Remove shmid. If shmat() is successful, the actual shared memory segment 2343 // will be deleted when it's detached by shmdt() or when the process 2344 // terminates. If shmat() is not successful this will remove the shared 2345 // segment immediately. 2346 shmctl(shmid, IPC_RMID, NULL); 2347 2348 if ((intptr_t)addr == -1) { 2349 if (warn_on_failure) { 2350 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 2351 warning(msg); 2352 } 2353 return NULL; 2354 } 2355 2356 // The memory is committed 2357 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC); 2358 2359 return addr; 2360} 2361 2362bool os::release_memory_special(char* base, size_t bytes) { 2363 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2364 // detaching the SHM segment will also delete it, see reserve_memory_special() 2365 int rslt = shmdt(base); 2366 if (rslt == 0) { 2367 tkr.record((address)base, bytes); 2368 return true; 2369 } else { 2370 tkr.discard(); 2371 return false; 2372 } 2373 2374} 2375 2376size_t os::large_page_size() { 2377 return _large_page_size; 2378} 2379 2380// HugeTLBFS allows application to commit large page memory on demand; 2381// with SysV SHM the entire memory region must be allocated as shared 2382// memory. 2383bool os::can_commit_large_page_memory() { 2384 return UseHugeTLBFS; 2385} 2386 2387bool os::can_execute_large_page_memory() { 2388 return UseHugeTLBFS; 2389} 2390 2391// Reserve memory at an arbitrary address, only if that area is 2392// available (and not reserved for something else). 2393 2394char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2395 const int max_tries = 10; 2396 char* base[max_tries]; 2397 size_t size[max_tries]; 2398 const size_t gap = 0x000000; 2399 2400 // Assert only that the size is a multiple of the page size, since 2401 // that's all that mmap requires, and since that's all we really know 2402 // about at this low abstraction level. If we need higher alignment, 2403 // we can either pass an alignment to this method or verify alignment 2404 // in one of the methods further up the call chain. See bug 5044738. 2405 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2406 2407 // Repeatedly allocate blocks until the block is allocated at the 2408 // right spot. Give up after max_tries. Note that reserve_memory() will 2409 // automatically update _highest_vm_reserved_address if the call is 2410 // successful. The variable tracks the highest memory address every reserved 2411 // by JVM. It is used to detect heap-stack collision if running with 2412 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2413 // space than needed, it could confuse the collision detecting code. To 2414 // solve the problem, save current _highest_vm_reserved_address and 2415 // calculate the correct value before return. 2416 address old_highest = _highest_vm_reserved_address; 2417 2418 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2419 // if kernel honors the hint then we can return immediately. 2420 char * addr = anon_mmap(requested_addr, bytes, false); 2421 if (addr == requested_addr) { 2422 return requested_addr; 2423 } 2424 2425 if (addr != NULL) { 2426 // mmap() is successful but it fails to reserve at the requested address 2427 anon_munmap(addr, bytes); 2428 } 2429 2430 int i; 2431 for (i = 0; i < max_tries; ++i) { 2432 base[i] = reserve_memory(bytes); 2433 2434 if (base[i] != NULL) { 2435 // Is this the block we wanted? 2436 if (base[i] == requested_addr) { 2437 size[i] = bytes; 2438 break; 2439 } 2440 2441 // Does this overlap the block we wanted? Give back the overlapped 2442 // parts and try again. 2443 2444 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2445 if (top_overlap >= 0 && top_overlap < bytes) { 2446 unmap_memory(base[i], top_overlap); 2447 base[i] += top_overlap; 2448 size[i] = bytes - top_overlap; 2449 } else { 2450 size_t bottom_overlap = base[i] + bytes - requested_addr; 2451 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2452 unmap_memory(requested_addr, bottom_overlap); 2453 size[i] = bytes - bottom_overlap; 2454 } else { 2455 size[i] = bytes; 2456 } 2457 } 2458 } 2459 } 2460 2461 // Give back the unused reserved pieces. 2462 2463 for (int j = 0; j < i; ++j) { 2464 if (base[j] != NULL) { 2465 unmap_memory(base[j], size[j]); 2466 } 2467 } 2468 2469 if (i < max_tries) { 2470 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2471 return requested_addr; 2472 } else { 2473 _highest_vm_reserved_address = old_highest; 2474 return NULL; 2475 } 2476} 2477 2478size_t os::read(int fd, void *buf, unsigned int nBytes) { 2479 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2480} 2481 2482// TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation. 2483// Solaris uses poll(), bsd uses park(). 2484// Poll() is likely a better choice, assuming that Thread.interrupt() 2485// generates a SIGUSRx signal. Note that SIGUSR1 can interfere with 2486// SIGSEGV, see 4355769. 2487 2488int os::sleep(Thread* thread, jlong millis, bool interruptible) { 2489 assert(thread == Thread::current(), "thread consistency check"); 2490 2491 ParkEvent * const slp = thread->_SleepEvent ; 2492 slp->reset() ; 2493 OrderAccess::fence() ; 2494 2495 if (interruptible) { 2496 jlong prevtime = javaTimeNanos(); 2497 2498 for (;;) { 2499 if (os::is_interrupted(thread, true)) { 2500 return OS_INTRPT; 2501 } 2502 2503 jlong newtime = javaTimeNanos(); 2504 2505 if (newtime - prevtime < 0) { 2506 // time moving backwards, should only happen if no monotonic clock 2507 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2508 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2509 } else { 2510 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2511 } 2512 2513 if(millis <= 0) { 2514 return OS_OK; 2515 } 2516 2517 prevtime = newtime; 2518 2519 { 2520 assert(thread->is_Java_thread(), "sanity check"); 2521 JavaThread *jt = (JavaThread *) thread; 2522 ThreadBlockInVM tbivm(jt); 2523 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 2524 2525 jt->set_suspend_equivalent(); 2526 // cleared by handle_special_suspend_equivalent_condition() or 2527 // java_suspend_self() via check_and_wait_while_suspended() 2528 2529 slp->park(millis); 2530 2531 // were we externally suspended while we were waiting? 2532 jt->check_and_wait_while_suspended(); 2533 } 2534 } 2535 } else { 2536 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 2537 jlong prevtime = javaTimeNanos(); 2538 2539 for (;;) { 2540 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 2541 // the 1st iteration ... 2542 jlong newtime = javaTimeNanos(); 2543 2544 if (newtime - prevtime < 0) { 2545 // time moving backwards, should only happen if no monotonic clock 2546 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2547 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2548 } else { 2549 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2550 } 2551 2552 if(millis <= 0) break ; 2553 2554 prevtime = newtime; 2555 slp->park(millis); 2556 } 2557 return OS_OK ; 2558 } 2559} 2560 2561int os::naked_sleep() { 2562 // %% make the sleep time an integer flag. for now use 1 millisec. 2563 return os::sleep(Thread::current(), 1, false); 2564} 2565 2566// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2567void os::infinite_sleep() { 2568 while (true) { // sleep forever ... 2569 ::sleep(100); // ... 100 seconds at a time 2570 } 2571} 2572 2573// Used to convert frequent JVM_Yield() to nops 2574bool os::dont_yield() { 2575 return DontYieldALot; 2576} 2577 2578void os::yield() { 2579 sched_yield(); 2580} 2581 2582os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 2583 2584void os::yield_all(int attempts) { 2585 // Yields to all threads, including threads with lower priorities 2586 // Threads on Bsd are all with same priority. The Solaris style 2587 // os::yield_all() with nanosleep(1ms) is not necessary. 2588 sched_yield(); 2589} 2590 2591// Called from the tight loops to possibly influence time-sharing heuristics 2592void os::loop_breaker(int attempts) { 2593 os::yield_all(attempts); 2594} 2595 2596//////////////////////////////////////////////////////////////////////////////// 2597// thread priority support 2598 2599// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2600// only supports dynamic priority, static priority must be zero. For real-time 2601// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2602// However, for large multi-threaded applications, SCHED_RR is not only slower 2603// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2604// of 5 runs - Sep 2005). 2605// 2606// The following code actually changes the niceness of kernel-thread/LWP. It 2607// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2608// not the entire user process, and user level threads are 1:1 mapped to kernel 2609// threads. It has always been the case, but could change in the future. For 2610// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2611// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2612 2613#if !defined(__APPLE__) 2614int os::java_to_os_priority[CriticalPriority + 1] = { 2615 19, // 0 Entry should never be used 2616 2617 0, // 1 MinPriority 2618 3, // 2 2619 6, // 3 2620 2621 10, // 4 2622 15, // 5 NormPriority 2623 18, // 6 2624 2625 21, // 7 2626 25, // 8 2627 28, // 9 NearMaxPriority 2628 2629 31, // 10 MaxPriority 2630 2631 31 // 11 CriticalPriority 2632}; 2633#else 2634/* Using Mach high-level priority assignments */ 2635int os::java_to_os_priority[CriticalPriority + 1] = { 2636 0, // 0 Entry should never be used (MINPRI_USER) 2637 2638 27, // 1 MinPriority 2639 28, // 2 2640 29, // 3 2641 2642 30, // 4 2643 31, // 5 NormPriority (BASEPRI_DEFAULT) 2644 32, // 6 2645 2646 33, // 7 2647 34, // 8 2648 35, // 9 NearMaxPriority 2649 2650 36, // 10 MaxPriority 2651 2652 36 // 11 CriticalPriority 2653}; 2654#endif 2655 2656static int prio_init() { 2657 if (ThreadPriorityPolicy == 1) { 2658 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2659 // if effective uid is not root. Perhaps, a more elegant way of doing 2660 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2661 if (geteuid() != 0) { 2662 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2663 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2664 } 2665 ThreadPriorityPolicy = 0; 2666 } 2667 } 2668 if (UseCriticalJavaThreadPriority) { 2669 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2670 } 2671 return 0; 2672} 2673 2674OSReturn os::set_native_priority(Thread* thread, int newpri) { 2675 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 2676 2677#ifdef __OpenBSD__ 2678 // OpenBSD pthread_setprio starves low priority threads 2679 return OS_OK; 2680#elif defined(__FreeBSD__) 2681 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2682#elif defined(__APPLE__) || defined(__NetBSD__) 2683 struct sched_param sp; 2684 int policy; 2685 pthread_t self = pthread_self(); 2686 2687 if (pthread_getschedparam(self, &policy, &sp) != 0) 2688 return OS_ERR; 2689 2690 sp.sched_priority = newpri; 2691 if (pthread_setschedparam(self, policy, &sp) != 0) 2692 return OS_ERR; 2693 2694 return OS_OK; 2695#else 2696 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2697 return (ret == 0) ? OS_OK : OS_ERR; 2698#endif 2699} 2700 2701OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2702 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 2703 *priority_ptr = java_to_os_priority[NormPriority]; 2704 return OS_OK; 2705 } 2706 2707 errno = 0; 2708#if defined(__OpenBSD__) || defined(__FreeBSD__) 2709 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2710#elif defined(__APPLE__) || defined(__NetBSD__) 2711 int policy; 2712 struct sched_param sp; 2713 2714 pthread_getschedparam(pthread_self(), &policy, &sp); 2715 *priority_ptr = sp.sched_priority; 2716#else 2717 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2718#endif 2719 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2720} 2721 2722// Hint to the underlying OS that a task switch would not be good. 2723// Void return because it's a hint and can fail. 2724void os::hint_no_preempt() {} 2725 2726//////////////////////////////////////////////////////////////////////////////// 2727// suspend/resume support 2728 2729// the low-level signal-based suspend/resume support is a remnant from the 2730// old VM-suspension that used to be for java-suspension, safepoints etc, 2731// within hotspot. Now there is a single use-case for this: 2732// - calling get_thread_pc() on the VMThread by the flat-profiler task 2733// that runs in the watcher thread. 2734// The remaining code is greatly simplified from the more general suspension 2735// code that used to be used. 2736// 2737// The protocol is quite simple: 2738// - suspend: 2739// - sends a signal to the target thread 2740// - polls the suspend state of the osthread using a yield loop 2741// - target thread signal handler (SR_handler) sets suspend state 2742// and blocks in sigsuspend until continued 2743// - resume: 2744// - sets target osthread state to continue 2745// - sends signal to end the sigsuspend loop in the SR_handler 2746// 2747// Note that the SR_lock plays no role in this suspend/resume protocol. 2748// 2749 2750static void resume_clear_context(OSThread *osthread) { 2751 osthread->set_ucontext(NULL); 2752 osthread->set_siginfo(NULL); 2753} 2754 2755static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2756 osthread->set_ucontext(context); 2757 osthread->set_siginfo(siginfo); 2758} 2759 2760// 2761// Handler function invoked when a thread's execution is suspended or 2762// resumed. We have to be careful that only async-safe functions are 2763// called here (Note: most pthread functions are not async safe and 2764// should be avoided.) 2765// 2766// Note: sigwait() is a more natural fit than sigsuspend() from an 2767// interface point of view, but sigwait() prevents the signal hander 2768// from being run. libpthread would get very confused by not having 2769// its signal handlers run and prevents sigwait()'s use with the 2770// mutex granting granting signal. 2771// 2772// Currently only ever called on the VMThread or JavaThread 2773// 2774static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2775 // Save and restore errno to avoid confusing native code with EINTR 2776 // after sigsuspend. 2777 int old_errno = errno; 2778 2779 Thread* thread = Thread::current(); 2780 OSThread* osthread = thread->osthread(); 2781 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2782 2783 os::SuspendResume::State current = osthread->sr.state(); 2784 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2785 suspend_save_context(osthread, siginfo, context); 2786 2787 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2788 os::SuspendResume::State state = osthread->sr.suspended(); 2789 if (state == os::SuspendResume::SR_SUSPENDED) { 2790 sigset_t suspend_set; // signals for sigsuspend() 2791 2792 // get current set of blocked signals and unblock resume signal 2793 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2794 sigdelset(&suspend_set, SR_signum); 2795 2796 sr_semaphore.signal(); 2797 // wait here until we are resumed 2798 while (1) { 2799 sigsuspend(&suspend_set); 2800 2801 os::SuspendResume::State result = osthread->sr.running(); 2802 if (result == os::SuspendResume::SR_RUNNING) { 2803 sr_semaphore.signal(); 2804 break; 2805 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2806 ShouldNotReachHere(); 2807 } 2808 } 2809 2810 } else if (state == os::SuspendResume::SR_RUNNING) { 2811 // request was cancelled, continue 2812 } else { 2813 ShouldNotReachHere(); 2814 } 2815 2816 resume_clear_context(osthread); 2817 } else if (current == os::SuspendResume::SR_RUNNING) { 2818 // request was cancelled, continue 2819 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2820 // ignore 2821 } else { 2822 // ignore 2823 } 2824 2825 errno = old_errno; 2826} 2827 2828 2829static int SR_initialize() { 2830 struct sigaction act; 2831 char *s; 2832 /* Get signal number to use for suspend/resume */ 2833 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2834 int sig = ::strtol(s, 0, 10); 2835 if (sig > 0 || sig < NSIG) { 2836 SR_signum = sig; 2837 } 2838 } 2839 2840 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2841 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2842 2843 sigemptyset(&SR_sigset); 2844 sigaddset(&SR_sigset, SR_signum); 2845 2846 /* Set up signal handler for suspend/resume */ 2847 act.sa_flags = SA_RESTART|SA_SIGINFO; 2848 act.sa_handler = (void (*)(int)) SR_handler; 2849 2850 // SR_signum is blocked by default. 2851 // 4528190 - We also need to block pthread restart signal (32 on all 2852 // supported Bsd platforms). Note that BsdThreads need to block 2853 // this signal for all threads to work properly. So we don't have 2854 // to use hard-coded signal number when setting up the mask. 2855 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2856 2857 if (sigaction(SR_signum, &act, 0) == -1) { 2858 return -1; 2859 } 2860 2861 // Save signal flag 2862 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2863 return 0; 2864} 2865 2866static int sr_notify(OSThread* osthread) { 2867 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2868 assert_status(status == 0, status, "pthread_kill"); 2869 return status; 2870} 2871 2872// "Randomly" selected value for how long we want to spin 2873// before bailing out on suspending a thread, also how often 2874// we send a signal to a thread we want to resume 2875static const int RANDOMLY_LARGE_INTEGER = 1000000; 2876static const int RANDOMLY_LARGE_INTEGER2 = 100; 2877 2878// returns true on success and false on error - really an error is fatal 2879// but this seems the normal response to library errors 2880static bool do_suspend(OSThread* osthread) { 2881 assert(osthread->sr.is_running(), "thread should be running"); 2882 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2883 2884 // mark as suspended and send signal 2885 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2886 // failed to switch, state wasn't running? 2887 ShouldNotReachHere(); 2888 return false; 2889 } 2890 2891 if (sr_notify(osthread) != 0) { 2892 ShouldNotReachHere(); 2893 } 2894 2895 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2896 while (true) { 2897 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2898 break; 2899 } else { 2900 // timeout 2901 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2902 if (cancelled == os::SuspendResume::SR_RUNNING) { 2903 return false; 2904 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2905 // make sure that we consume the signal on the semaphore as well 2906 sr_semaphore.wait(); 2907 break; 2908 } else { 2909 ShouldNotReachHere(); 2910 return false; 2911 } 2912 } 2913 } 2914 2915 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2916 return true; 2917} 2918 2919static void do_resume(OSThread* osthread) { 2920 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2921 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2922 2923 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2924 // failed to switch to WAKEUP_REQUEST 2925 ShouldNotReachHere(); 2926 return; 2927 } 2928 2929 while (true) { 2930 if (sr_notify(osthread) == 0) { 2931 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2932 if (osthread->sr.is_running()) { 2933 return; 2934 } 2935 } 2936 } else { 2937 ShouldNotReachHere(); 2938 } 2939 } 2940 2941 guarantee(osthread->sr.is_running(), "Must be running!"); 2942} 2943 2944//////////////////////////////////////////////////////////////////////////////// 2945// interrupt support 2946 2947void os::interrupt(Thread* thread) { 2948 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 2949 "possibility of dangling Thread pointer"); 2950 2951 OSThread* osthread = thread->osthread(); 2952 2953 if (!osthread->interrupted()) { 2954 osthread->set_interrupted(true); 2955 // More than one thread can get here with the same value of osthread, 2956 // resulting in multiple notifications. We do, however, want the store 2957 // to interrupted() to be visible to other threads before we execute unpark(). 2958 OrderAccess::fence(); 2959 ParkEvent * const slp = thread->_SleepEvent ; 2960 if (slp != NULL) slp->unpark() ; 2961 } 2962 2963 // For JSR166. Unpark even if interrupt status already was set 2964 if (thread->is_Java_thread()) 2965 ((JavaThread*)thread)->parker()->unpark(); 2966 2967 ParkEvent * ev = thread->_ParkEvent ; 2968 if (ev != NULL) ev->unpark() ; 2969 2970} 2971 2972bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 2973 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 2974 "possibility of dangling Thread pointer"); 2975 2976 OSThread* osthread = thread->osthread(); 2977 2978 bool interrupted = osthread->interrupted(); 2979 2980 if (interrupted && clear_interrupted) { 2981 osthread->set_interrupted(false); 2982 // consider thread->_SleepEvent->reset() ... optional optimization 2983 } 2984 2985 return interrupted; 2986} 2987 2988/////////////////////////////////////////////////////////////////////////////////// 2989// signal handling (except suspend/resume) 2990 2991// This routine may be used by user applications as a "hook" to catch signals. 2992// The user-defined signal handler must pass unrecognized signals to this 2993// routine, and if it returns true (non-zero), then the signal handler must 2994// return immediately. If the flag "abort_if_unrecognized" is true, then this 2995// routine will never retun false (zero), but instead will execute a VM panic 2996// routine kill the process. 2997// 2998// If this routine returns false, it is OK to call it again. This allows 2999// the user-defined signal handler to perform checks either before or after 3000// the VM performs its own checks. Naturally, the user code would be making 3001// a serious error if it tried to handle an exception (such as a null check 3002// or breakpoint) that the VM was generating for its own correct operation. 3003// 3004// This routine may recognize any of the following kinds of signals: 3005// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 3006// It should be consulted by handlers for any of those signals. 3007// 3008// The caller of this routine must pass in the three arguments supplied 3009// to the function referred to in the "sa_sigaction" (not the "sa_handler") 3010// field of the structure passed to sigaction(). This routine assumes that 3011// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 3012// 3013// Note that the VM will print warnings if it detects conflicting signal 3014// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 3015// 3016extern "C" JNIEXPORT int 3017JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 3018 void* ucontext, int abort_if_unrecognized); 3019 3020void signalHandler(int sig, siginfo_t* info, void* uc) { 3021 assert(info != NULL && uc != NULL, "it must be old kernel"); 3022 int orig_errno = errno; // Preserve errno value over signal handler. 3023 JVM_handle_bsd_signal(sig, info, uc, true); 3024 errno = orig_errno; 3025} 3026 3027 3028// This boolean allows users to forward their own non-matching signals 3029// to JVM_handle_bsd_signal, harmlessly. 3030bool os::Bsd::signal_handlers_are_installed = false; 3031 3032// For signal-chaining 3033struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3034unsigned int os::Bsd::sigs = 0; 3035bool os::Bsd::libjsig_is_loaded = false; 3036typedef struct sigaction *(*get_signal_t)(int); 3037get_signal_t os::Bsd::get_signal_action = NULL; 3038 3039struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3040 struct sigaction *actp = NULL; 3041 3042 if (libjsig_is_loaded) { 3043 // Retrieve the old signal handler from libjsig 3044 actp = (*get_signal_action)(sig); 3045 } 3046 if (actp == NULL) { 3047 // Retrieve the preinstalled signal handler from jvm 3048 actp = get_preinstalled_handler(sig); 3049 } 3050 3051 return actp; 3052} 3053 3054static bool call_chained_handler(struct sigaction *actp, int sig, 3055 siginfo_t *siginfo, void *context) { 3056 // Call the old signal handler 3057 if (actp->sa_handler == SIG_DFL) { 3058 // It's more reasonable to let jvm treat it as an unexpected exception 3059 // instead of taking the default action. 3060 return false; 3061 } else if (actp->sa_handler != SIG_IGN) { 3062 if ((actp->sa_flags & SA_NODEFER) == 0) { 3063 // automaticlly block the signal 3064 sigaddset(&(actp->sa_mask), sig); 3065 } 3066 3067 sa_handler_t hand; 3068 sa_sigaction_t sa; 3069 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3070 // retrieve the chained handler 3071 if (siginfo_flag_set) { 3072 sa = actp->sa_sigaction; 3073 } else { 3074 hand = actp->sa_handler; 3075 } 3076 3077 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3078 actp->sa_handler = SIG_DFL; 3079 } 3080 3081 // try to honor the signal mask 3082 sigset_t oset; 3083 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3084 3085 // call into the chained handler 3086 if (siginfo_flag_set) { 3087 (*sa)(sig, siginfo, context); 3088 } else { 3089 (*hand)(sig); 3090 } 3091 3092 // restore the signal mask 3093 pthread_sigmask(SIG_SETMASK, &oset, 0); 3094 } 3095 // Tell jvm's signal handler the signal is taken care of. 3096 return true; 3097} 3098 3099bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3100 bool chained = false; 3101 // signal-chaining 3102 if (UseSignalChaining) { 3103 struct sigaction *actp = get_chained_signal_action(sig); 3104 if (actp != NULL) { 3105 chained = call_chained_handler(actp, sig, siginfo, context); 3106 } 3107 } 3108 return chained; 3109} 3110 3111struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3112 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 3113 return &sigact[sig]; 3114 } 3115 return NULL; 3116} 3117 3118void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3119 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3120 sigact[sig] = oldAct; 3121 sigs |= (unsigned int)1 << sig; 3122} 3123 3124// for diagnostic 3125int os::Bsd::sigflags[MAXSIGNUM]; 3126 3127int os::Bsd::get_our_sigflags(int sig) { 3128 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3129 return sigflags[sig]; 3130} 3131 3132void os::Bsd::set_our_sigflags(int sig, int flags) { 3133 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3134 sigflags[sig] = flags; 3135} 3136 3137void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3138 // Check for overwrite. 3139 struct sigaction oldAct; 3140 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3141 3142 void* oldhand = oldAct.sa_sigaction 3143 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3144 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3145 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3146 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3147 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3148 if (AllowUserSignalHandlers || !set_installed) { 3149 // Do not overwrite; user takes responsibility to forward to us. 3150 return; 3151 } else if (UseSignalChaining) { 3152 // save the old handler in jvm 3153 save_preinstalled_handler(sig, oldAct); 3154 // libjsig also interposes the sigaction() call below and saves the 3155 // old sigaction on it own. 3156 } else { 3157 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3158 "%#lx for signal %d.", (long)oldhand, sig)); 3159 } 3160 } 3161 3162 struct sigaction sigAct; 3163 sigfillset(&(sigAct.sa_mask)); 3164 sigAct.sa_handler = SIG_DFL; 3165 if (!set_installed) { 3166 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3167 } else { 3168 sigAct.sa_sigaction = signalHandler; 3169 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3170 } 3171#if __APPLE__ 3172 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3173 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3174 // if the signal handler declares it will handle it on alternate stack. 3175 // Notice we only declare we will handle it on alt stack, but we are not 3176 // actually going to use real alt stack - this is just a workaround. 3177 // Please see ux_exception.c, method catch_mach_exception_raise for details 3178 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3179 if (sig == SIGSEGV) { 3180 sigAct.sa_flags |= SA_ONSTACK; 3181 } 3182#endif 3183 3184 // Save flags, which are set by ours 3185 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3186 sigflags[sig] = sigAct.sa_flags; 3187 3188 int ret = sigaction(sig, &sigAct, &oldAct); 3189 assert(ret == 0, "check"); 3190 3191 void* oldhand2 = oldAct.sa_sigaction 3192 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3193 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3194 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3195} 3196 3197// install signal handlers for signals that HotSpot needs to 3198// handle in order to support Java-level exception handling. 3199 3200void os::Bsd::install_signal_handlers() { 3201 if (!signal_handlers_are_installed) { 3202 signal_handlers_are_installed = true; 3203 3204 // signal-chaining 3205 typedef void (*signal_setting_t)(); 3206 signal_setting_t begin_signal_setting = NULL; 3207 signal_setting_t end_signal_setting = NULL; 3208 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3209 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3210 if (begin_signal_setting != NULL) { 3211 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3212 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3213 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3214 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3215 libjsig_is_loaded = true; 3216 assert(UseSignalChaining, "should enable signal-chaining"); 3217 } 3218 if (libjsig_is_loaded) { 3219 // Tell libjsig jvm is setting signal handlers 3220 (*begin_signal_setting)(); 3221 } 3222 3223 set_signal_handler(SIGSEGV, true); 3224 set_signal_handler(SIGPIPE, true); 3225 set_signal_handler(SIGBUS, true); 3226 set_signal_handler(SIGILL, true); 3227 set_signal_handler(SIGFPE, true); 3228 set_signal_handler(SIGXFSZ, true); 3229 3230#if defined(__APPLE__) 3231 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3232 // signals caught and handled by the JVM. To work around this, we reset the mach task 3233 // signal handler that's placed on our process by CrashReporter. This disables 3234 // CrashReporter-based reporting. 3235 // 3236 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3237 // on caught fatal signals. 3238 // 3239 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3240 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3241 // exception handling, while leaving the standard BSD signal handlers functional. 3242 kern_return_t kr; 3243 kr = task_set_exception_ports(mach_task_self(), 3244 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3245 MACH_PORT_NULL, 3246 EXCEPTION_STATE_IDENTITY, 3247 MACHINE_THREAD_STATE); 3248 3249 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3250#endif 3251 3252 if (libjsig_is_loaded) { 3253 // Tell libjsig jvm finishes setting signal handlers 3254 (*end_signal_setting)(); 3255 } 3256 3257 // We don't activate signal checker if libjsig is in place, we trust ourselves 3258 // and if UserSignalHandler is installed all bets are off 3259 if (CheckJNICalls) { 3260 if (libjsig_is_loaded) { 3261 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3262 check_signals = false; 3263 } 3264 if (AllowUserSignalHandlers) { 3265 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3266 check_signals = false; 3267 } 3268 } 3269 } 3270} 3271 3272 3273///// 3274// glibc on Bsd platform uses non-documented flag 3275// to indicate, that some special sort of signal 3276// trampoline is used. 3277// We will never set this flag, and we should 3278// ignore this flag in our diagnostic 3279#ifdef SIGNIFICANT_SIGNAL_MASK 3280#undef SIGNIFICANT_SIGNAL_MASK 3281#endif 3282#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3283 3284static const char* get_signal_handler_name(address handler, 3285 char* buf, int buflen) { 3286 int offset; 3287 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3288 if (found) { 3289 // skip directory names 3290 const char *p1, *p2; 3291 p1 = buf; 3292 size_t len = strlen(os::file_separator()); 3293 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3294 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3295 } else { 3296 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3297 } 3298 return buf; 3299} 3300 3301static void print_signal_handler(outputStream* st, int sig, 3302 char* buf, size_t buflen) { 3303 struct sigaction sa; 3304 3305 sigaction(sig, NULL, &sa); 3306 3307 // See comment for SIGNIFICANT_SIGNAL_MASK define 3308 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3309 3310 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3311 3312 address handler = (sa.sa_flags & SA_SIGINFO) 3313 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3314 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3315 3316 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3317 st->print("SIG_DFL"); 3318 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3319 st->print("SIG_IGN"); 3320 } else { 3321 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3322 } 3323 3324 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask); 3325 3326 address rh = VMError::get_resetted_sighandler(sig); 3327 // May be, handler was resetted by VMError? 3328 if(rh != NULL) { 3329 handler = rh; 3330 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3331 } 3332 3333 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags); 3334 3335 // Check: is it our handler? 3336 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3337 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3338 // It is our signal handler 3339 // check for flags, reset system-used one! 3340 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3341 st->print( 3342 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3343 os::Bsd::get_our_sigflags(sig)); 3344 } 3345 } 3346 st->cr(); 3347} 3348 3349 3350#define DO_SIGNAL_CHECK(sig) \ 3351 if (!sigismember(&check_signal_done, sig)) \ 3352 os::Bsd::check_signal_handler(sig) 3353 3354// This method is a periodic task to check for misbehaving JNI applications 3355// under CheckJNI, we can add any periodic checks here 3356 3357void os::run_periodic_checks() { 3358 3359 if (check_signals == false) return; 3360 3361 // SEGV and BUS if overridden could potentially prevent 3362 // generation of hs*.log in the event of a crash, debugging 3363 // such a case can be very challenging, so we absolutely 3364 // check the following for a good measure: 3365 DO_SIGNAL_CHECK(SIGSEGV); 3366 DO_SIGNAL_CHECK(SIGILL); 3367 DO_SIGNAL_CHECK(SIGFPE); 3368 DO_SIGNAL_CHECK(SIGBUS); 3369 DO_SIGNAL_CHECK(SIGPIPE); 3370 DO_SIGNAL_CHECK(SIGXFSZ); 3371 3372 3373 // ReduceSignalUsage allows the user to override these handlers 3374 // see comments at the very top and jvm_solaris.h 3375 if (!ReduceSignalUsage) { 3376 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3377 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3378 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3379 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3380 } 3381 3382 DO_SIGNAL_CHECK(SR_signum); 3383 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3384} 3385 3386typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3387 3388static os_sigaction_t os_sigaction = NULL; 3389 3390void os::Bsd::check_signal_handler(int sig) { 3391 char buf[O_BUFLEN]; 3392 address jvmHandler = NULL; 3393 3394 3395 struct sigaction act; 3396 if (os_sigaction == NULL) { 3397 // only trust the default sigaction, in case it has been interposed 3398 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3399 if (os_sigaction == NULL) return; 3400 } 3401 3402 os_sigaction(sig, (struct sigaction*)NULL, &act); 3403 3404 3405 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3406 3407 address thisHandler = (act.sa_flags & SA_SIGINFO) 3408 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3409 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 3410 3411 3412 switch(sig) { 3413 case SIGSEGV: 3414 case SIGBUS: 3415 case SIGFPE: 3416 case SIGPIPE: 3417 case SIGILL: 3418 case SIGXFSZ: 3419 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3420 break; 3421 3422 case SHUTDOWN1_SIGNAL: 3423 case SHUTDOWN2_SIGNAL: 3424 case SHUTDOWN3_SIGNAL: 3425 case BREAK_SIGNAL: 3426 jvmHandler = (address)user_handler(); 3427 break; 3428 3429 case INTERRUPT_SIGNAL: 3430 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3431 break; 3432 3433 default: 3434 if (sig == SR_signum) { 3435 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3436 } else { 3437 return; 3438 } 3439 break; 3440 } 3441 3442 if (thisHandler != jvmHandler) { 3443 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3444 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3445 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3446 // No need to check this sig any longer 3447 sigaddset(&check_signal_done, sig); 3448 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3449 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3450 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3451 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3452 // No need to check this sig any longer 3453 sigaddset(&check_signal_done, sig); 3454 } 3455 3456 // Dump all the signal 3457 if (sigismember(&check_signal_done, sig)) { 3458 print_signal_handlers(tty, buf, O_BUFLEN); 3459 } 3460} 3461 3462extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3463 3464extern bool signal_name(int signo, char* buf, size_t len); 3465 3466const char* os::exception_name(int exception_code, char* buf, size_t size) { 3467 if (0 < exception_code && exception_code <= SIGRTMAX) { 3468 // signal 3469 if (!signal_name(exception_code, buf, size)) { 3470 jio_snprintf(buf, size, "SIG%d", exception_code); 3471 } 3472 return buf; 3473 } else { 3474 return NULL; 3475 } 3476} 3477 3478// this is called _before_ the most of global arguments have been parsed 3479void os::init(void) { 3480 char dummy; /* used to get a guess on initial stack address */ 3481// first_hrtime = gethrtime(); 3482 3483 // With BsdThreads the JavaMain thread pid (primordial thread) 3484 // is different than the pid of the java launcher thread. 3485 // So, on Bsd, the launcher thread pid is passed to the VM 3486 // via the sun.java.launcher.pid property. 3487 // Use this property instead of getpid() if it was correctly passed. 3488 // See bug 6351349. 3489 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3490 3491 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3492 3493 clock_tics_per_sec = CLK_TCK; 3494 3495 init_random(1234567); 3496 3497 ThreadCritical::initialize(); 3498 3499 Bsd::set_page_size(getpagesize()); 3500 if (Bsd::page_size() == -1) { 3501 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3502 strerror(errno))); 3503 } 3504 init_page_sizes((size_t) Bsd::page_size()); 3505 3506 Bsd::initialize_system_info(); 3507 3508 // main_thread points to the aboriginal thread 3509 Bsd::_main_thread = pthread_self(); 3510 3511 Bsd::clock_init(); 3512 initial_time_count = os::elapsed_counter(); 3513 3514#ifdef __APPLE__ 3515 // XXXDARWIN 3516 // Work around the unaligned VM callbacks in hotspot's 3517 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3518 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3519 // alignment when doing symbol lookup. To work around this, we force early 3520 // binding of all symbols now, thus binding when alignment is known-good. 3521 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3522#endif 3523} 3524 3525// To install functions for atexit system call 3526extern "C" { 3527 static void perfMemory_exit_helper() { 3528 perfMemory_exit(); 3529 } 3530} 3531 3532// this is called _after_ the global arguments have been parsed 3533jint os::init_2(void) 3534{ 3535 // Allocate a single page and mark it as readable for safepoint polling 3536 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3537 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 3538 3539 os::set_polling_page( polling_page ); 3540 3541#ifndef PRODUCT 3542 if(Verbose && PrintMiscellaneous) 3543 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3544#endif 3545 3546 if (!UseMembar) { 3547 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3548 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3549 os::set_memory_serialize_page( mem_serialize_page ); 3550 3551#ifndef PRODUCT 3552 if(Verbose && PrintMiscellaneous) 3553 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3554#endif 3555 } 3556 3557 os::large_page_init(); 3558 3559 // initialize suspend/resume support - must do this before signal_sets_init() 3560 if (SR_initialize() != 0) { 3561 perror("SR_initialize failed"); 3562 return JNI_ERR; 3563 } 3564 3565 Bsd::signal_sets_init(); 3566 Bsd::install_signal_handlers(); 3567 3568 // Check minimum allowable stack size for thread creation and to initialize 3569 // the java system classes, including StackOverflowError - depends on page 3570 // size. Add a page for compiler2 recursion in main thread. 3571 // Add in 2*BytesPerWord times page size to account for VM stack during 3572 // class initialization depending on 32 or 64 bit VM. 3573 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3574 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3575 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3576 3577 size_t threadStackSizeInBytes = ThreadStackSize * K; 3578 if (threadStackSizeInBytes != 0 && 3579 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3580 tty->print_cr("\nThe stack size specified is too small, " 3581 "Specify at least %dk", 3582 os::Bsd::min_stack_allowed/ K); 3583 return JNI_ERR; 3584 } 3585 3586 // Make the stack size a multiple of the page size so that 3587 // the yellow/red zones can be guarded. 3588 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3589 vm_page_size())); 3590 3591 if (MaxFDLimit) { 3592 // set the number of file descriptors to max. print out error 3593 // if getrlimit/setrlimit fails but continue regardless. 3594 struct rlimit nbr_files; 3595 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3596 if (status != 0) { 3597 if (PrintMiscellaneous && (Verbose || WizardMode)) 3598 perror("os::init_2 getrlimit failed"); 3599 } else { 3600 nbr_files.rlim_cur = nbr_files.rlim_max; 3601 3602#ifdef __APPLE__ 3603 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3604 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3605 // be used instead 3606 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3607#endif 3608 3609 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3610 if (status != 0) { 3611 if (PrintMiscellaneous && (Verbose || WizardMode)) 3612 perror("os::init_2 setrlimit failed"); 3613 } 3614 } 3615 } 3616 3617 // at-exit methods are called in the reverse order of their registration. 3618 // atexit functions are called on return from main or as a result of a 3619 // call to exit(3C). There can be only 32 of these functions registered 3620 // and atexit() does not set errno. 3621 3622 if (PerfAllowAtExitRegistration) { 3623 // only register atexit functions if PerfAllowAtExitRegistration is set. 3624 // atexit functions can be delayed until process exit time, which 3625 // can be problematic for embedded VM situations. Embedded VMs should 3626 // call DestroyJavaVM() to assure that VM resources are released. 3627 3628 // note: perfMemory_exit_helper atexit function may be removed in 3629 // the future if the appropriate cleanup code can be added to the 3630 // VM_Exit VMOperation's doit method. 3631 if (atexit(perfMemory_exit_helper) != 0) { 3632 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3633 } 3634 } 3635 3636 // initialize thread priority policy 3637 prio_init(); 3638 3639#ifdef __APPLE__ 3640 // dynamically link to objective c gc registration 3641 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3642 if (handleLibObjc != NULL) { 3643 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3644 } 3645#endif 3646 3647 return JNI_OK; 3648} 3649 3650// this is called at the end of vm_initialization 3651void os::init_3(void) { } 3652 3653// Mark the polling page as unreadable 3654void os::make_polling_page_unreadable(void) { 3655 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 3656 fatal("Could not disable polling page"); 3657}; 3658 3659// Mark the polling page as readable 3660void os::make_polling_page_readable(void) { 3661 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3662 fatal("Could not enable polling page"); 3663 } 3664}; 3665 3666int os::active_processor_count() { 3667 return _processor_count; 3668} 3669 3670void os::set_native_thread_name(const char *name) { 3671#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3672 // This is only supported in Snow Leopard and beyond 3673 if (name != NULL) { 3674 // Add a "Java: " prefix to the name 3675 char buf[MAXTHREADNAMESIZE]; 3676 snprintf(buf, sizeof(buf), "Java: %s", name); 3677 pthread_setname_np(buf); 3678 } 3679#endif 3680} 3681 3682bool os::distribute_processes(uint length, uint* distribution) { 3683 // Not yet implemented. 3684 return false; 3685} 3686 3687bool os::bind_to_processor(uint processor_id) { 3688 // Not yet implemented. 3689 return false; 3690} 3691 3692void os::SuspendedThreadTask::internal_do_task() { 3693 if (do_suspend(_thread->osthread())) { 3694 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3695 do_task(context); 3696 do_resume(_thread->osthread()); 3697 } 3698} 3699 3700/// 3701class PcFetcher : public os::SuspendedThreadTask { 3702public: 3703 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3704 ExtendedPC result(); 3705protected: 3706 void do_task(const os::SuspendedThreadTaskContext& context); 3707private: 3708 ExtendedPC _epc; 3709}; 3710 3711ExtendedPC PcFetcher::result() { 3712 guarantee(is_done(), "task is not done yet."); 3713 return _epc; 3714} 3715 3716void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3717 Thread* thread = context.thread(); 3718 OSThread* osthread = thread->osthread(); 3719 if (osthread->ucontext() != NULL) { 3720 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3721 } else { 3722 // NULL context is unexpected, double-check this is the VMThread 3723 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3724 } 3725} 3726 3727// Suspends the target using the signal mechanism and then grabs the PC before 3728// resuming the target. Used by the flat-profiler only 3729ExtendedPC os::get_thread_pc(Thread* thread) { 3730 // Make sure that it is called by the watcher for the VMThread 3731 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3732 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3733 3734 PcFetcher fetcher(thread); 3735 fetcher.run(); 3736 return fetcher.result(); 3737} 3738 3739int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3740{ 3741 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3742} 3743 3744//////////////////////////////////////////////////////////////////////////////// 3745// debug support 3746 3747bool os::find(address addr, outputStream* st) { 3748 Dl_info dlinfo; 3749 memset(&dlinfo, 0, sizeof(dlinfo)); 3750 if (dladdr(addr, &dlinfo)) { 3751 st->print(PTR_FORMAT ": ", addr); 3752 if (dlinfo.dli_sname != NULL) { 3753 st->print("%s+%#x", dlinfo.dli_sname, 3754 addr - (intptr_t)dlinfo.dli_saddr); 3755 } else if (dlinfo.dli_fname) { 3756 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3757 } else { 3758 st->print("<absolute address>"); 3759 } 3760 if (dlinfo.dli_fname) { 3761 st->print(" in %s", dlinfo.dli_fname); 3762 } 3763 if (dlinfo.dli_fbase) { 3764 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3765 } 3766 st->cr(); 3767 3768 if (Verbose) { 3769 // decode some bytes around the PC 3770 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3771 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3772 address lowest = (address) dlinfo.dli_sname; 3773 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3774 if (begin < lowest) begin = lowest; 3775 Dl_info dlinfo2; 3776 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr 3777 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3778 end = (address) dlinfo2.dli_saddr; 3779 Disassembler::decode(begin, end, st); 3780 } 3781 return true; 3782 } 3783 return false; 3784} 3785 3786//////////////////////////////////////////////////////////////////////////////// 3787// misc 3788 3789// This does not do anything on Bsd. This is basically a hook for being 3790// able to use structured exception handling (thread-local exception filters) 3791// on, e.g., Win32. 3792void 3793os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3794 JavaCallArguments* args, Thread* thread) { 3795 f(value, method, args, thread); 3796} 3797 3798void os::print_statistics() { 3799} 3800 3801int os::message_box(const char* title, const char* message) { 3802 int i; 3803 fdStream err(defaultStream::error_fd()); 3804 for (i = 0; i < 78; i++) err.print_raw("="); 3805 err.cr(); 3806 err.print_raw_cr(title); 3807 for (i = 0; i < 78; i++) err.print_raw("-"); 3808 err.cr(); 3809 err.print_raw_cr(message); 3810 for (i = 0; i < 78; i++) err.print_raw("="); 3811 err.cr(); 3812 3813 char buf[16]; 3814 // Prevent process from exiting upon "read error" without consuming all CPU 3815 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3816 3817 return buf[0] == 'y' || buf[0] == 'Y'; 3818} 3819 3820int os::stat(const char *path, struct stat *sbuf) { 3821 char pathbuf[MAX_PATH]; 3822 if (strlen(path) > MAX_PATH - 1) { 3823 errno = ENAMETOOLONG; 3824 return -1; 3825 } 3826 os::native_path(strcpy(pathbuf, path)); 3827 return ::stat(pathbuf, sbuf); 3828} 3829 3830bool os::check_heap(bool force) { 3831 return true; 3832} 3833 3834int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 3835 return ::vsnprintf(buf, count, format, args); 3836} 3837 3838// Is a (classpath) directory empty? 3839bool os::dir_is_empty(const char* path) { 3840 DIR *dir = NULL; 3841 struct dirent *ptr; 3842 3843 dir = opendir(path); 3844 if (dir == NULL) return true; 3845 3846 /* Scan the directory */ 3847 bool result = true; 3848 char buf[sizeof(struct dirent) + MAX_PATH]; 3849 while (result && (ptr = ::readdir(dir)) != NULL) { 3850 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3851 result = false; 3852 } 3853 } 3854 closedir(dir); 3855 return result; 3856} 3857 3858// This code originates from JDK's sysOpen and open64_w 3859// from src/solaris/hpi/src/system_md.c 3860 3861#ifndef O_DELETE 3862#define O_DELETE 0x10000 3863#endif 3864 3865// Open a file. Unlink the file immediately after open returns 3866// if the specified oflag has the O_DELETE flag set. 3867// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3868 3869int os::open(const char *path, int oflag, int mode) { 3870 3871 if (strlen(path) > MAX_PATH - 1) { 3872 errno = ENAMETOOLONG; 3873 return -1; 3874 } 3875 int fd; 3876 int o_delete = (oflag & O_DELETE); 3877 oflag = oflag & ~O_DELETE; 3878 3879 fd = ::open(path, oflag, mode); 3880 if (fd == -1) return -1; 3881 3882 //If the open succeeded, the file might still be a directory 3883 { 3884 struct stat buf; 3885 int ret = ::fstat(fd, &buf); 3886 int st_mode = buf.st_mode; 3887 3888 if (ret != -1) { 3889 if ((st_mode & S_IFMT) == S_IFDIR) { 3890 errno = EISDIR; 3891 ::close(fd); 3892 return -1; 3893 } 3894 } else { 3895 ::close(fd); 3896 return -1; 3897 } 3898 } 3899 3900 /* 3901 * All file descriptors that are opened in the JVM and not 3902 * specifically destined for a subprocess should have the 3903 * close-on-exec flag set. If we don't set it, then careless 3rd 3904 * party native code might fork and exec without closing all 3905 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3906 * UNIXProcess.c), and this in turn might: 3907 * 3908 * - cause end-of-file to fail to be detected on some file 3909 * descriptors, resulting in mysterious hangs, or 3910 * 3911 * - might cause an fopen in the subprocess to fail on a system 3912 * suffering from bug 1085341. 3913 * 3914 * (Yes, the default setting of the close-on-exec flag is a Unix 3915 * design flaw) 3916 * 3917 * See: 3918 * 1085341: 32-bit stdio routines should support file descriptors >255 3919 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3920 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3921 */ 3922#ifdef FD_CLOEXEC 3923 { 3924 int flags = ::fcntl(fd, F_GETFD); 3925 if (flags != -1) 3926 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3927 } 3928#endif 3929 3930 if (o_delete != 0) { 3931 ::unlink(path); 3932 } 3933 return fd; 3934} 3935 3936 3937// create binary file, rewriting existing file if required 3938int os::create_binary_file(const char* path, bool rewrite_existing) { 3939 int oflags = O_WRONLY | O_CREAT; 3940 if (!rewrite_existing) { 3941 oflags |= O_EXCL; 3942 } 3943 return ::open(path, oflags, S_IREAD | S_IWRITE); 3944} 3945 3946// return current position of file pointer 3947jlong os::current_file_offset(int fd) { 3948 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3949} 3950 3951// move file pointer to the specified offset 3952jlong os::seek_to_file_offset(int fd, jlong offset) { 3953 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3954} 3955 3956// This code originates from JDK's sysAvailable 3957// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3958 3959int os::available(int fd, jlong *bytes) { 3960 jlong cur, end; 3961 int mode; 3962 struct stat buf; 3963 3964 if (::fstat(fd, &buf) >= 0) { 3965 mode = buf.st_mode; 3966 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3967 /* 3968 * XXX: is the following call interruptible? If so, this might 3969 * need to go through the INTERRUPT_IO() wrapper as for other 3970 * blocking, interruptible calls in this file. 3971 */ 3972 int n; 3973 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3974 *bytes = n; 3975 return 1; 3976 } 3977 } 3978 } 3979 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3980 return 0; 3981 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3982 return 0; 3983 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3984 return 0; 3985 } 3986 *bytes = end - cur; 3987 return 1; 3988} 3989 3990int os::socket_available(int fd, jint *pbytes) { 3991 if (fd < 0) 3992 return OS_OK; 3993 3994 int ret; 3995 3996 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 3997 3998 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 3999 // is expected to return 0 on failure and 1 on success to the jdk. 4000 4001 return (ret == OS_ERR) ? 0 : 1; 4002} 4003 4004// Map a block of memory. 4005char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 4006 char *addr, size_t bytes, bool read_only, 4007 bool allow_exec) { 4008 int prot; 4009 int flags; 4010 4011 if (read_only) { 4012 prot = PROT_READ; 4013 flags = MAP_SHARED; 4014 } else { 4015 prot = PROT_READ | PROT_WRITE; 4016 flags = MAP_PRIVATE; 4017 } 4018 4019 if (allow_exec) { 4020 prot |= PROT_EXEC; 4021 } 4022 4023 if (addr != NULL) { 4024 flags |= MAP_FIXED; 4025 } 4026 4027 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4028 fd, file_offset); 4029 if (mapped_address == MAP_FAILED) { 4030 return NULL; 4031 } 4032 return mapped_address; 4033} 4034 4035 4036// Remap a block of memory. 4037char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4038 char *addr, size_t bytes, bool read_only, 4039 bool allow_exec) { 4040 // same as map_memory() on this OS 4041 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4042 allow_exec); 4043} 4044 4045 4046// Unmap a block of memory. 4047bool os::pd_unmap_memory(char* addr, size_t bytes) { 4048 return munmap(addr, bytes) == 0; 4049} 4050 4051// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4052// are used by JVM M&M and JVMTI to get user+sys or user CPU time 4053// of a thread. 4054// 4055// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4056// the fast estimate available on the platform. 4057 4058jlong os::current_thread_cpu_time() { 4059#ifdef __APPLE__ 4060 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4061#else 4062 Unimplemented(); 4063 return 0; 4064#endif 4065} 4066 4067jlong os::thread_cpu_time(Thread* thread) { 4068#ifdef __APPLE__ 4069 return os::thread_cpu_time(thread, true /* user + sys */); 4070#else 4071 Unimplemented(); 4072 return 0; 4073#endif 4074} 4075 4076jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4077#ifdef __APPLE__ 4078 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4079#else 4080 Unimplemented(); 4081 return 0; 4082#endif 4083} 4084 4085jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4086#ifdef __APPLE__ 4087 struct thread_basic_info tinfo; 4088 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4089 kern_return_t kr; 4090 thread_t mach_thread; 4091 4092 mach_thread = thread->osthread()->thread_id(); 4093 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4094 if (kr != KERN_SUCCESS) 4095 return -1; 4096 4097 if (user_sys_cpu_time) { 4098 jlong nanos; 4099 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4100 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4101 return nanos; 4102 } else { 4103 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4104 } 4105#else 4106 Unimplemented(); 4107 return 0; 4108#endif 4109} 4110 4111 4112void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4113 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4114 info_ptr->may_skip_backward = false; // elapsed time not wall time 4115 info_ptr->may_skip_forward = false; // elapsed time not wall time 4116 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4117} 4118 4119void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4120 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4121 info_ptr->may_skip_backward = false; // elapsed time not wall time 4122 info_ptr->may_skip_forward = false; // elapsed time not wall time 4123 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4124} 4125 4126bool os::is_thread_cpu_time_supported() { 4127#ifdef __APPLE__ 4128 return true; 4129#else 4130 return false; 4131#endif 4132} 4133 4134// System loadavg support. Returns -1 if load average cannot be obtained. 4135// Bsd doesn't yet have a (official) notion of processor sets, 4136// so just return the system wide load average. 4137int os::loadavg(double loadavg[], int nelem) { 4138 return ::getloadavg(loadavg, nelem); 4139} 4140 4141void os::pause() { 4142 char filename[MAX_PATH]; 4143 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4144 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4145 } else { 4146 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4147 } 4148 4149 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4150 if (fd != -1) { 4151 struct stat buf; 4152 ::close(fd); 4153 while (::stat(filename, &buf) == 0) { 4154 (void)::poll(NULL, 0, 100); 4155 } 4156 } else { 4157 jio_fprintf(stderr, 4158 "Could not open pause file '%s', continuing immediately.\n", filename); 4159 } 4160} 4161 4162 4163// Refer to the comments in os_solaris.cpp park-unpark. 4164// 4165// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4166// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4167// For specifics regarding the bug see GLIBC BUGID 261237 : 4168// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4169// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4170// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4171// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4172// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4173// and monitorenter when we're using 1-0 locking. All those operations may result in 4174// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4175// of libpthread avoids the problem, but isn't practical. 4176// 4177// Possible remedies: 4178// 4179// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4180// This is palliative and probabilistic, however. If the thread is preempted 4181// between the call to compute_abstime() and pthread_cond_timedwait(), more 4182// than the minimum period may have passed, and the abstime may be stale (in the 4183// past) resultin in a hang. Using this technique reduces the odds of a hang 4184// but the JVM is still vulnerable, particularly on heavily loaded systems. 4185// 4186// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4187// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4188// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4189// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4190// thread. 4191// 4192// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4193// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4194// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4195// This also works well. In fact it avoids kernel-level scalability impediments 4196// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4197// timers in a graceful fashion. 4198// 4199// 4. When the abstime value is in the past it appears that control returns 4200// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4201// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4202// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4203// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4204// It may be possible to avoid reinitialization by checking the return 4205// value from pthread_cond_timedwait(). In addition to reinitializing the 4206// condvar we must establish the invariant that cond_signal() is only called 4207// within critical sections protected by the adjunct mutex. This prevents 4208// cond_signal() from "seeing" a condvar that's in the midst of being 4209// reinitialized or that is corrupt. Sadly, this invariant obviates the 4210// desirable signal-after-unlock optimization that avoids futile context switching. 4211// 4212// I'm also concerned that some versions of NTPL might allocate an auxilliary 4213// structure when a condvar is used or initialized. cond_destroy() would 4214// release the helper structure. Our reinitialize-after-timedwait fix 4215// put excessive stress on malloc/free and locks protecting the c-heap. 4216// 4217// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4218// It may be possible to refine (4) by checking the kernel and NTPL verisons 4219// and only enabling the work-around for vulnerable environments. 4220 4221// utility to compute the abstime argument to timedwait: 4222// millis is the relative timeout time 4223// abstime will be the absolute timeout time 4224// TODO: replace compute_abstime() with unpackTime() 4225 4226static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4227 if (millis < 0) millis = 0; 4228 struct timeval now; 4229 int status = gettimeofday(&now, NULL); 4230 assert(status == 0, "gettimeofday"); 4231 jlong seconds = millis / 1000; 4232 millis %= 1000; 4233 if (seconds > 50000000) { // see man cond_timedwait(3T) 4234 seconds = 50000000; 4235 } 4236 abstime->tv_sec = now.tv_sec + seconds; 4237 long usec = now.tv_usec + millis * 1000; 4238 if (usec >= 1000000) { 4239 abstime->tv_sec += 1; 4240 usec -= 1000000; 4241 } 4242 abstime->tv_nsec = usec * 1000; 4243 return abstime; 4244} 4245 4246 4247// Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 4248// Conceptually TryPark() should be equivalent to park(0). 4249 4250int os::PlatformEvent::TryPark() { 4251 for (;;) { 4252 const int v = _Event ; 4253 guarantee ((v == 0) || (v == 1), "invariant") ; 4254 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 4255 } 4256} 4257 4258void os::PlatformEvent::park() { // AKA "down()" 4259 // Invariant: Only the thread associated with the Event/PlatformEvent 4260 // may call park(). 4261 // TODO: assert that _Assoc != NULL or _Assoc == Self 4262 int v ; 4263 for (;;) { 4264 v = _Event ; 4265 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4266 } 4267 guarantee (v >= 0, "invariant") ; 4268 if (v == 0) { 4269 // Do this the hard way by blocking ... 4270 int status = pthread_mutex_lock(_mutex); 4271 assert_status(status == 0, status, "mutex_lock"); 4272 guarantee (_nParked == 0, "invariant") ; 4273 ++ _nParked ; 4274 while (_Event < 0) { 4275 status = pthread_cond_wait(_cond, _mutex); 4276 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4277 // Treat this the same as if the wait was interrupted 4278 if (status == ETIMEDOUT) { status = EINTR; } 4279 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4280 } 4281 -- _nParked ; 4282 4283 _Event = 0 ; 4284 status = pthread_mutex_unlock(_mutex); 4285 assert_status(status == 0, status, "mutex_unlock"); 4286 // Paranoia to ensure our locked and lock-free paths interact 4287 // correctly with each other. 4288 OrderAccess::fence(); 4289 } 4290 guarantee (_Event >= 0, "invariant") ; 4291} 4292 4293int os::PlatformEvent::park(jlong millis) { 4294 guarantee (_nParked == 0, "invariant") ; 4295 4296 int v ; 4297 for (;;) { 4298 v = _Event ; 4299 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4300 } 4301 guarantee (v >= 0, "invariant") ; 4302 if (v != 0) return OS_OK ; 4303 4304 // We do this the hard way, by blocking the thread. 4305 // Consider enforcing a minimum timeout value. 4306 struct timespec abst; 4307 compute_abstime(&abst, millis); 4308 4309 int ret = OS_TIMEOUT; 4310 int status = pthread_mutex_lock(_mutex); 4311 assert_status(status == 0, status, "mutex_lock"); 4312 guarantee (_nParked == 0, "invariant") ; 4313 ++_nParked ; 4314 4315 // Object.wait(timo) will return because of 4316 // (a) notification 4317 // (b) timeout 4318 // (c) thread.interrupt 4319 // 4320 // Thread.interrupt and object.notify{All} both call Event::set. 4321 // That is, we treat thread.interrupt as a special case of notification. 4322 // The underlying Solaris implementation, cond_timedwait, admits 4323 // spurious/premature wakeups, but the JLS/JVM spec prevents the 4324 // JVM from making those visible to Java code. As such, we must 4325 // filter out spurious wakeups. We assume all ETIME returns are valid. 4326 // 4327 // TODO: properly differentiate simultaneous notify+interrupt. 4328 // In that case, we should propagate the notify to another waiter. 4329 4330 while (_Event < 0) { 4331 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4332 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4333 pthread_cond_destroy (_cond); 4334 pthread_cond_init (_cond, NULL) ; 4335 } 4336 assert_status(status == 0 || status == EINTR || 4337 status == ETIMEDOUT, 4338 status, "cond_timedwait"); 4339 if (!FilterSpuriousWakeups) break ; // previous semantics 4340 if (status == ETIMEDOUT) break ; 4341 // We consume and ignore EINTR and spurious wakeups. 4342 } 4343 --_nParked ; 4344 if (_Event >= 0) { 4345 ret = OS_OK; 4346 } 4347 _Event = 0 ; 4348 status = pthread_mutex_unlock(_mutex); 4349 assert_status(status == 0, status, "mutex_unlock"); 4350 assert (_nParked == 0, "invariant") ; 4351 // Paranoia to ensure our locked and lock-free paths interact 4352 // correctly with each other. 4353 OrderAccess::fence(); 4354 return ret; 4355} 4356 4357void os::PlatformEvent::unpark() { 4358 // Transitions for _Event: 4359 // 0 :=> 1 4360 // 1 :=> 1 4361 // -1 :=> either 0 or 1; must signal target thread 4362 // That is, we can safely transition _Event from -1 to either 4363 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back 4364 // unpark() calls. 4365 // See also: "Semaphores in Plan 9" by Mullender & Cox 4366 // 4367 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4368 // that it will take two back-to-back park() calls for the owning 4369 // thread to block. This has the benefit of forcing a spurious return 4370 // from the first park() call after an unpark() call which will help 4371 // shake out uses of park() and unpark() without condition variables. 4372 4373 if (Atomic::xchg(1, &_Event) >= 0) return; 4374 4375 // Wait for the thread associated with the event to vacate 4376 int status = pthread_mutex_lock(_mutex); 4377 assert_status(status == 0, status, "mutex_lock"); 4378 int AnyWaiters = _nParked; 4379 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4380 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4381 AnyWaiters = 0; 4382 pthread_cond_signal(_cond); 4383 } 4384 status = pthread_mutex_unlock(_mutex); 4385 assert_status(status == 0, status, "mutex_unlock"); 4386 if (AnyWaiters != 0) { 4387 status = pthread_cond_signal(_cond); 4388 assert_status(status == 0, status, "cond_signal"); 4389 } 4390 4391 // Note that we signal() _after dropping the lock for "immortal" Events. 4392 // This is safe and avoids a common class of futile wakeups. In rare 4393 // circumstances this can cause a thread to return prematurely from 4394 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4395 // simply re-test the condition and re-park itself. 4396} 4397 4398 4399// JSR166 4400// ------------------------------------------------------- 4401 4402/* 4403 * The solaris and bsd implementations of park/unpark are fairly 4404 * conservative for now, but can be improved. They currently use a 4405 * mutex/condvar pair, plus a a count. 4406 * Park decrements count if > 0, else does a condvar wait. Unpark 4407 * sets count to 1 and signals condvar. Only one thread ever waits 4408 * on the condvar. Contention seen when trying to park implies that someone 4409 * is unparking you, so don't wait. And spurious returns are fine, so there 4410 * is no need to track notifications. 4411 */ 4412 4413#define MAX_SECS 100000000 4414/* 4415 * This code is common to bsd and solaris and will be moved to a 4416 * common place in dolphin. 4417 * 4418 * The passed in time value is either a relative time in nanoseconds 4419 * or an absolute time in milliseconds. Either way it has to be unpacked 4420 * into suitable seconds and nanoseconds components and stored in the 4421 * given timespec structure. 4422 * Given time is a 64-bit value and the time_t used in the timespec is only 4423 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4424 * overflow if times way in the future are given. Further on Solaris versions 4425 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4426 * number of seconds, in abstime, is less than current_time + 100,000,000. 4427 * As it will be 28 years before "now + 100000000" will overflow we can 4428 * ignore overflow and just impose a hard-limit on seconds using the value 4429 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4430 * years from "now". 4431 */ 4432 4433static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4434 assert (time > 0, "convertTime"); 4435 4436 struct timeval now; 4437 int status = gettimeofday(&now, NULL); 4438 assert(status == 0, "gettimeofday"); 4439 4440 time_t max_secs = now.tv_sec + MAX_SECS; 4441 4442 if (isAbsolute) { 4443 jlong secs = time / 1000; 4444 if (secs > max_secs) { 4445 absTime->tv_sec = max_secs; 4446 } 4447 else { 4448 absTime->tv_sec = secs; 4449 } 4450 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4451 } 4452 else { 4453 jlong secs = time / NANOSECS_PER_SEC; 4454 if (secs >= MAX_SECS) { 4455 absTime->tv_sec = max_secs; 4456 absTime->tv_nsec = 0; 4457 } 4458 else { 4459 absTime->tv_sec = now.tv_sec + secs; 4460 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4461 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4462 absTime->tv_nsec -= NANOSECS_PER_SEC; 4463 ++absTime->tv_sec; // note: this must be <= max_secs 4464 } 4465 } 4466 } 4467 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4468 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4469 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4470 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4471} 4472 4473void Parker::park(bool isAbsolute, jlong time) { 4474 // Ideally we'd do something useful while spinning, such 4475 // as calling unpackTime(). 4476 4477 // Optional fast-path check: 4478 // Return immediately if a permit is available. 4479 // We depend on Atomic::xchg() having full barrier semantics 4480 // since we are doing a lock-free update to _counter. 4481 if (Atomic::xchg(0, &_counter) > 0) return; 4482 4483 Thread* thread = Thread::current(); 4484 assert(thread->is_Java_thread(), "Must be JavaThread"); 4485 JavaThread *jt = (JavaThread *)thread; 4486 4487 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4488 // Check interrupt before trying to wait 4489 if (Thread::is_interrupted(thread, false)) { 4490 return; 4491 } 4492 4493 // Next, demultiplex/decode time arguments 4494 struct timespec absTime; 4495 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 4496 return; 4497 } 4498 if (time > 0) { 4499 unpackTime(&absTime, isAbsolute, time); 4500 } 4501 4502 4503 // Enter safepoint region 4504 // Beware of deadlocks such as 6317397. 4505 // The per-thread Parker:: mutex is a classic leaf-lock. 4506 // In particular a thread must never block on the Threads_lock while 4507 // holding the Parker:: mutex. If safepoints are pending both the 4508 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4509 ThreadBlockInVM tbivm(jt); 4510 4511 // Don't wait if cannot get lock since interference arises from 4512 // unblocking. Also. check interrupt before trying wait 4513 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4514 return; 4515 } 4516 4517 int status ; 4518 if (_counter > 0) { // no wait needed 4519 _counter = 0; 4520 status = pthread_mutex_unlock(_mutex); 4521 assert (status == 0, "invariant") ; 4522 // Paranoia to ensure our locked and lock-free paths interact 4523 // correctly with each other and Java-level accesses. 4524 OrderAccess::fence(); 4525 return; 4526 } 4527 4528#ifdef ASSERT 4529 // Don't catch signals while blocked; let the running threads have the signals. 4530 // (This allows a debugger to break into the running thread.) 4531 sigset_t oldsigs; 4532 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4533 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4534#endif 4535 4536 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4537 jt->set_suspend_equivalent(); 4538 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4539 4540 if (time == 0) { 4541 status = pthread_cond_wait (_cond, _mutex) ; 4542 } else { 4543 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 4544 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4545 pthread_cond_destroy (_cond) ; 4546 pthread_cond_init (_cond, NULL); 4547 } 4548 } 4549 assert_status(status == 0 || status == EINTR || 4550 status == ETIMEDOUT, 4551 status, "cond_timedwait"); 4552 4553#ifdef ASSERT 4554 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4555#endif 4556 4557 _counter = 0 ; 4558 status = pthread_mutex_unlock(_mutex) ; 4559 assert_status(status == 0, status, "invariant") ; 4560 // Paranoia to ensure our locked and lock-free paths interact 4561 // correctly with each other and Java-level accesses. 4562 OrderAccess::fence(); 4563 4564 // If externally suspended while waiting, re-suspend 4565 if (jt->handle_special_suspend_equivalent_condition()) { 4566 jt->java_suspend_self(); 4567 } 4568} 4569 4570void Parker::unpark() { 4571 int s, status ; 4572 status = pthread_mutex_lock(_mutex); 4573 assert (status == 0, "invariant") ; 4574 s = _counter; 4575 _counter = 1; 4576 if (s < 1) { 4577 if (WorkAroundNPTLTimedWaitHang) { 4578 status = pthread_cond_signal (_cond) ; 4579 assert (status == 0, "invariant") ; 4580 status = pthread_mutex_unlock(_mutex); 4581 assert (status == 0, "invariant") ; 4582 } else { 4583 status = pthread_mutex_unlock(_mutex); 4584 assert (status == 0, "invariant") ; 4585 status = pthread_cond_signal (_cond) ; 4586 assert (status == 0, "invariant") ; 4587 } 4588 } else { 4589 pthread_mutex_unlock(_mutex); 4590 assert (status == 0, "invariant") ; 4591 } 4592} 4593 4594 4595/* Darwin has no "environ" in a dynamic library. */ 4596#ifdef __APPLE__ 4597#include <crt_externs.h> 4598#define environ (*_NSGetEnviron()) 4599#else 4600extern char** environ; 4601#endif 4602 4603// Run the specified command in a separate process. Return its exit value, 4604// or -1 on failure (e.g. can't fork a new process). 4605// Unlike system(), this function can be called from signal handler. It 4606// doesn't block SIGINT et al. 4607int os::fork_and_exec(char* cmd) { 4608 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4609 4610 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4611 // pthread_atfork handlers and reset pthread library. All we need is a 4612 // separate process to execve. Make a direct syscall to fork process. 4613 // On IA64 there's no fork syscall, we have to use fork() and hope for 4614 // the best... 4615 pid_t pid = fork(); 4616 4617 if (pid < 0) { 4618 // fork failed 4619 return -1; 4620 4621 } else if (pid == 0) { 4622 // child process 4623 4624 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4625 // first to kill every thread on the thread list. Because this list is 4626 // not reset by fork() (see notes above), execve() will instead kill 4627 // every thread in the parent process. We know this is the only thread 4628 // in the new process, so make a system call directly. 4629 // IA64 should use normal execve() from glibc to match the glibc fork() 4630 // above. 4631 execve("/bin/sh", (char* const*)argv, environ); 4632 4633 // execve failed 4634 _exit(-1); 4635 4636 } else { 4637 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4638 // care about the actual exit code, for now. 4639 4640 int status; 4641 4642 // Wait for the child process to exit. This returns immediately if 4643 // the child has already exited. */ 4644 while (waitpid(pid, &status, 0) < 0) { 4645 switch (errno) { 4646 case ECHILD: return 0; 4647 case EINTR: break; 4648 default: return -1; 4649 } 4650 } 4651 4652 if (WIFEXITED(status)) { 4653 // The child exited normally; get its exit code. 4654 return WEXITSTATUS(status); 4655 } else if (WIFSIGNALED(status)) { 4656 // The child exited because of a signal 4657 // The best value to return is 0x80 + signal number, 4658 // because that is what all Unix shells do, and because 4659 // it allows callers to distinguish between process exit and 4660 // process death by signal. 4661 return 0x80 + WTERMSIG(status); 4662 } else { 4663 // Unknown exit code; pass it through 4664 return status; 4665 } 4666 } 4667} 4668 4669// is_headless_jre() 4670// 4671// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4672// in order to report if we are running in a headless jre 4673// 4674// Since JDK8 xawt/libmawt.so was moved into the same directory 4675// as libawt.so, and renamed libawt_xawt.so 4676// 4677bool os::is_headless_jre() { 4678 struct stat statbuf; 4679 char buf[MAXPATHLEN]; 4680 char libmawtpath[MAXPATHLEN]; 4681 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4682 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4683 char *p; 4684 4685 // Get path to libjvm.so 4686 os::jvm_path(buf, sizeof(buf)); 4687 4688 // Get rid of libjvm.so 4689 p = strrchr(buf, '/'); 4690 if (p == NULL) return false; 4691 else *p = '\0'; 4692 4693 // Get rid of client or server 4694 p = strrchr(buf, '/'); 4695 if (p == NULL) return false; 4696 else *p = '\0'; 4697 4698 // check xawt/libmawt.so 4699 strcpy(libmawtpath, buf); 4700 strcat(libmawtpath, xawtstr); 4701 if (::stat(libmawtpath, &statbuf) == 0) return false; 4702 4703 // check libawt_xawt.so 4704 strcpy(libmawtpath, buf); 4705 strcat(libmawtpath, new_xawtstr); 4706 if (::stat(libmawtpath, &statbuf) == 0) return false; 4707 4708 return true; 4709} 4710 4711// Get the default path to the core file 4712// Returns the length of the string 4713int os::get_core_path(char* buffer, size_t bufferSize) { 4714 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4715 4716 // Truncate if theoretical string was longer than bufferSize 4717 n = MIN2(n, (int)bufferSize); 4718 4719 return n; 4720} 4721 4722