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 127 julong os::Bsd::_physical_memory = 0; 128 129 130 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 131 pthread_t os::Bsd::_main_thread; 132 int os::Bsd::_page_size = -1; 133 134 static jlong initial_time_count=0; 135 136 static int clock_tics_per_sec = 100; 137 138 // For diagnostics to print a message once. see run_periodic_checks 139 static sigset_t check_signal_done; 140 static bool check_signals = true; 141 142 static 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 */ 147 static int SR_signum = SIGUSR2; 148 sigset_t SR_sigset; 149 150 151 //////////////////////////////////////////////////////////////////////////////// 152 // utility functions 153 154 static int SR_initialize(); 155 156 julong os::available_memory() { 157 return Bsd::available_memory(); 158 } 159 160 julong os::Bsd::available_memory() { 161 // XXXBSD: this is just a stopgap implementation 162 return physical_memory() >> 2; 163 } 164 165 julong os::physical_memory() { 166 return Bsd::physical_memory(); 167 } 168 169 //////////////////////////////////////////////////////////////////////////////// 170 // environment support 171 172 bool 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. 184 185 bool 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) 199 static char cpu_arch[] = ZERO_LIBARCH; 200 #elif defined(IA64) 201 static char cpu_arch[] = "ia64"; 202 #elif defined(IA32) 203 static char cpu_arch[] = "i386"; 204 #elif defined(AMD64) 205 static char cpu_arch[] = "amd64"; 206 #elif defined(ARM) 207 static char cpu_arch[] = "arm"; 208 #elif defined(PPC) 209 static char cpu_arch[] = "ppc"; 210 #elif defined(SPARC) 211 # ifdef _LP64 212 static char cpu_arch[] = "sparcv9"; 213 # else 214 static 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 226 227 228 void 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__ 271 static 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 283 284 void 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 511 512 void os::breakpoint() { 513 BREAKPOINT; 514 } 515 516 extern "C" void breakpoint() { 517 // use debugger to set breakpoint here 518 } 519 520 //////////////////////////////////////////////////////////////////////////////// 521 // signal support 522 523 debug_only(static bool signal_sets_initialized = false); 524 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 525 526 bool 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 } 536 537 void 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.) 585 sigset_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. 592 sigset_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 598 sigset_t* os::Bsd::allowdebug_blocked_signals() { 599 assert(signal_sets_initialized, "Not initialized"); 600 return &allowdebug_blocked_sigs; 601 } 602 603 void 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 630 static 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" 639 typedef void (*objc_registerThreadWithCollector_t)(); 640 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 641 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 642 #endif 643 644 #ifdef __APPLE__ 645 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 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_port, THREAD_IDENTIFIER_INFO, 651 (thread_info_t) &m_ident_info, &count); 652 653 return m_ident_info.thread_id; 654 } 655 #endif 656 657 // Thread start routine for all newly created threads 658 static void *java_start(Thread *thread) { 659 // Try to randomize the cache line index of hot stack frames. 660 // This helps when threads of the same stack traces evict each other's 661 // cache lines. The threads can be either from the same JVM instance, or 662 // from different JVM instances. The benefit is especially true for 663 // processors with hyperthreading technology. 664 static int counter = 0; 665 int pid = os::current_process_id(); 666 alloca(((pid ^ counter++) & 7) * 128); 667 668 ThreadLocalStorage::set_thread(thread); 669 670 OSThread* osthread = thread->osthread(); 671 Monitor* sync = osthread->startThread_lock(); 672 673 // non floating stack BsdThreads needs extra check, see above 674 if (!_thread_safety_check(thread)) { 675 // notify parent thread 676 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 677 osthread->set_state(ZOMBIE); 678 sync->notify_all(); 679 return NULL; 680 } 681 682 #ifdef __APPLE__ 683 // thread_id is mach thread on macos, which pthreads graciously caches and provides for us 684 mach_port_t thread_id = ::pthread_mach_thread_np(::pthread_self()); 685 guarantee(thread_id != 0, "thread id missing from pthreads"); 686 osthread->set_thread_id(thread_id); 687 688 uint64_t unique_thread_id = locate_unique_thread_id(thread_id); 689 guarantee(unique_thread_id != 0, "unique thread id was not found"); 690 osthread->set_unique_thread_id(unique_thread_id); 691 #else 692 // thread_id is pthread_id on BSD 693 osthread->set_thread_id(::pthread_self()); 694 #endif 695 // initialize signal mask for this thread 696 os::Bsd::hotspot_sigmask(thread); 697 698 // initialize floating point control register 699 os::Bsd::init_thread_fpu_state(); 700 701 #ifdef __APPLE__ 702 // register thread with objc gc 703 if (objc_registerThreadWithCollectorFunction != NULL) { 704 objc_registerThreadWithCollectorFunction(); 705 } 706 #endif 707 708 // handshaking with parent thread 709 { 710 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 711 712 // notify parent thread 713 osthread->set_state(INITIALIZED); 714 sync->notify_all(); 715 716 // wait until os::start_thread() 717 while (osthread->get_state() == INITIALIZED) { 718 sync->wait(Mutex::_no_safepoint_check_flag); 719 } 720 } 721 722 // call one more level start routine 723 thread->run(); 724 725 return 0; 726 } 727 728 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 729 assert(thread->osthread() == NULL, "caller responsible"); 730 731 // Allocate the OSThread object 732 OSThread* osthread = new OSThread(NULL, NULL); 733 if (osthread == NULL) { 734 return false; 735 } 736 737 // set the correct thread state 738 osthread->set_thread_type(thr_type); 739 740 // Initial state is ALLOCATED but not INITIALIZED 741 osthread->set_state(ALLOCATED); 742 743 thread->set_osthread(osthread); 744 745 // init thread attributes 746 pthread_attr_t attr; 747 pthread_attr_init(&attr); 748 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 749 750 // stack size 751 if (os::Bsd::supports_variable_stack_size()) { 752 // calculate stack size if it's not specified by caller 753 if (stack_size == 0) { 754 stack_size = os::Bsd::default_stack_size(thr_type); 755 756 switch (thr_type) { 757 case os::java_thread: 758 // Java threads use ThreadStackSize which default value can be 759 // changed with the flag -Xss 760 assert (JavaThread::stack_size_at_create() > 0, "this should be set"); 761 stack_size = JavaThread::stack_size_at_create(); 762 break; 763 case os::compiler_thread: 764 if (CompilerThreadStackSize > 0) { 765 stack_size = (size_t)(CompilerThreadStackSize * K); 766 break; 767 } // else fall through: 768 // use VMThreadStackSize if CompilerThreadStackSize is not defined 769 case os::vm_thread: 770 case os::pgc_thread: 771 case os::cgc_thread: 772 case os::watcher_thread: 773 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 774 break; 775 } 776 } 777 778 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 779 pthread_attr_setstacksize(&attr, stack_size); 780 } else { 781 // let pthread_create() pick the default value. 782 } 783 784 ThreadState state; 785 786 { 787 pthread_t tid; 788 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 789 790 pthread_attr_destroy(&attr); 791 792 if (ret != 0) { 793 if (PrintMiscellaneous && (Verbose || WizardMode)) { 794 perror("pthread_create()"); 795 } 796 // Need to clean up stuff we've allocated so far 797 thread->set_osthread(NULL); 798 delete osthread; 799 return false; 800 } 801 802 // Store pthread info into the OSThread 803 osthread->set_pthread_id(tid); 804 805 // Wait until child thread is either initialized or aborted 806 { 807 Monitor* sync_with_child = osthread->startThread_lock(); 808 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 809 while ((state = osthread->get_state()) == ALLOCATED) { 810 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 811 } 812 } 813 814 } 815 816 // Aborted due to thread limit being reached 817 if (state == ZOMBIE) { 818 thread->set_osthread(NULL); 819 delete osthread; 820 return false; 821 } 822 823 // The thread is returned suspended (in state INITIALIZED), 824 // and is started higher up in the call chain 825 assert(state == INITIALIZED, "race condition"); 826 return true; 827 } 828 829 ///////////////////////////////////////////////////////////////////////////// 830 // attach existing thread 831 832 // bootstrap the main thread 833 bool os::create_main_thread(JavaThread* thread) { 834 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 835 return create_attached_thread(thread); 836 } 837 838 bool os::create_attached_thread(JavaThread* thread) { 839 #ifdef ASSERT 840 thread->verify_not_published(); 841 #endif 842 843 // Allocate the OSThread object 844 OSThread* osthread = new OSThread(NULL, NULL); 845 846 if (osthread == NULL) { 847 return false; 848 } 849 850 // Store pthread info into the OSThread 851 #ifdef __APPLE__ 852 // thread_id is mach thread on macos, which pthreads graciously caches and provides for us 853 mach_port_t thread_id = ::pthread_mach_thread_np(::pthread_self()); 854 guarantee(thread_id != 0, "just checking"); 855 osthread->set_thread_id(thread_id); 856 857 uint64_t unique_thread_id = locate_unique_thread_id(thread_id); 858 guarantee(unique_thread_id != 0, "just checking"); 859 osthread->set_unique_thread_id(unique_thread_id); 860 #else 861 osthread->set_thread_id(::pthread_self()); 862 #endif 863 osthread->set_pthread_id(::pthread_self()); 864 865 // initialize floating point control register 866 os::Bsd::init_thread_fpu_state(); 867 868 // Initial thread state is RUNNABLE 869 osthread->set_state(RUNNABLE); 870 871 thread->set_osthread(osthread); 872 873 // initialize signal mask for this thread 874 // and save the caller's signal mask 875 os::Bsd::hotspot_sigmask(thread); 876 877 return true; 878 } 879 880 void os::pd_start_thread(Thread* thread) { 881 OSThread * osthread = thread->osthread(); 882 assert(osthread->get_state() != INITIALIZED, "just checking"); 883 Monitor* sync_with_child = osthread->startThread_lock(); 884 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 885 sync_with_child->notify(); 886 } 887 888 // Free Bsd resources related to the OSThread 889 void os::free_thread(OSThread* osthread) { 890 assert(osthread != NULL, "osthread not set"); 891 892 if (Thread::current()->osthread() == osthread) { 893 // Restore caller's signal mask 894 sigset_t sigmask = osthread->caller_sigmask(); 895 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 896 } 897 898 delete osthread; 899 } 900 901 ////////////////////////////////////////////////////////////////////////////// 902 // thread local storage 903 904 int os::allocate_thread_local_storage() { 905 pthread_key_t key; 906 int rslt = pthread_key_create(&key, NULL); 907 assert(rslt == 0, "cannot allocate thread local storage"); 908 return (int)key; 909 } 910 911 // Note: This is currently not used by VM, as we don't destroy TLS key 912 // on VM exit. 913 void os::free_thread_local_storage(int index) { 914 int rslt = pthread_key_delete((pthread_key_t)index); 915 assert(rslt == 0, "invalid index"); 916 } 917 918 void os::thread_local_storage_at_put(int index, void* value) { 919 int rslt = pthread_setspecific((pthread_key_t)index, value); 920 assert(rslt == 0, "pthread_setspecific failed"); 921 } 922 923 extern "C" Thread* get_thread() { 924 return ThreadLocalStorage::thread(); 925 } 926 927 928 //////////////////////////////////////////////////////////////////////////////// 929 // time support 930 931 // Time since start-up in seconds to a fine granularity. 932 // Used by VMSelfDestructTimer and the MemProfiler. 933 double os::elapsedTime() { 934 935 return (double)(os::elapsed_counter()) * 0.000001; 936 } 937 938 jlong os::elapsed_counter() { 939 timeval time; 940 int status = gettimeofday(&time, NULL); 941 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count; 942 } 943 944 jlong os::elapsed_frequency() { 945 return (1000 * 1000); 946 } 947 948 bool os::supports_vtime() { return true; } 949 bool os::enable_vtime() { return false; } 950 bool os::vtime_enabled() { return false; } 951 952 double os::elapsedVTime() { 953 // better than nothing, but not much 954 return elapsedTime(); 955 } 956 957 jlong os::javaTimeMillis() { 958 timeval time; 959 int status = gettimeofday(&time, NULL); 960 assert(status != -1, "bsd error"); 961 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 962 } 963 964 #ifndef CLOCK_MONOTONIC 965 #define CLOCK_MONOTONIC (1) 966 #endif 967 968 #ifdef __APPLE__ 969 void os::Bsd::clock_init() { 970 // XXXDARWIN: Investigate replacement monotonic clock 971 } 972 #else 973 void os::Bsd::clock_init() { 974 struct timespec res; 975 struct timespec tp; 976 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 977 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 978 // yes, monotonic clock is supported 979 _clock_gettime = ::clock_gettime; 980 } 981 } 982 #endif 983 984 985 jlong os::javaTimeNanos() { 986 if (Bsd::supports_monotonic_clock()) { 987 struct timespec tp; 988 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp); 989 assert(status == 0, "gettime error"); 990 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 991 return result; 992 } else { 993 timeval time; 994 int status = gettimeofday(&time, NULL); 995 assert(status != -1, "bsd error"); 996 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 997 return 1000 * usecs; 998 } 999 } 1000 1001 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1002 if (Bsd::supports_monotonic_clock()) { 1003 info_ptr->max_value = ALL_64_BITS; 1004 1005 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1006 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1007 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1008 } else { 1009 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1010 info_ptr->max_value = ALL_64_BITS; 1011 1012 // gettimeofday is a real time clock so it skips 1013 info_ptr->may_skip_backward = true; 1014 info_ptr->may_skip_forward = true; 1015 } 1016 1017 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1018 } 1019 1020 // Return the real, user, and system times in seconds from an 1021 // arbitrary fixed point in the past. 1022 bool os::getTimesSecs(double* process_real_time, 1023 double* process_user_time, 1024 double* process_system_time) { 1025 struct tms ticks; 1026 clock_t real_ticks = times(&ticks); 1027 1028 if (real_ticks == (clock_t) (-1)) { 1029 return false; 1030 } else { 1031 double ticks_per_second = (double) clock_tics_per_sec; 1032 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1033 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1034 *process_real_time = ((double) real_ticks) / ticks_per_second; 1035 1036 return true; 1037 } 1038 } 1039 1040 1041 char * os::local_time_string(char *buf, size_t buflen) { 1042 struct tm t; 1043 time_t long_time; 1044 time(&long_time); 1045 localtime_r(&long_time, &t); 1046 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1047 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1048 t.tm_hour, t.tm_min, t.tm_sec); 1049 return buf; 1050 } 1051 1052 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1053 return localtime_r(clock, res); 1054 } 1055 1056 //////////////////////////////////////////////////////////////////////////////// 1057 // runtime exit support 1058 1059 // Note: os::shutdown() might be called very early during initialization, or 1060 // called from signal handler. Before adding something to os::shutdown(), make 1061 // sure it is async-safe and can handle partially initialized VM. 1062 void os::shutdown() { 1063 1064 // allow PerfMemory to attempt cleanup of any persistent resources 1065 perfMemory_exit(); 1066 1067 // needs to remove object in file system 1068 AttachListener::abort(); 1069 1070 // flush buffered output, finish log files 1071 ostream_abort(); 1072 1073 // Check for abort hook 1074 abort_hook_t abort_hook = Arguments::abort_hook(); 1075 if (abort_hook != NULL) { 1076 abort_hook(); 1077 } 1078 1079 } 1080 1081 // Note: os::abort() might be called very early during initialization, or 1082 // called from signal handler. Before adding something to os::abort(), make 1083 // sure it is async-safe and can handle partially initialized VM. 1084 void os::abort(bool dump_core) { 1085 os::shutdown(); 1086 if (dump_core) { 1087 #ifndef PRODUCT 1088 fdStream out(defaultStream::output_fd()); 1089 out.print_raw("Current thread is "); 1090 char buf[16]; 1091 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1092 out.print_raw_cr(buf); 1093 out.print_raw_cr("Dumping core ..."); 1094 #endif 1095 ::abort(); // dump core 1096 } 1097 1098 ::exit(1); 1099 } 1100 1101 // Die immediately, no exit hook, no abort hook, no cleanup. 1102 void os::die() { 1103 // _exit() on BsdThreads only kills current thread 1104 ::abort(); 1105 } 1106 1107 // unused on bsd for now. 1108 void os::set_error_file(const char *logfile) {} 1109 1110 1111 // This method is a copy of JDK's sysGetLastErrorString 1112 // from src/solaris/hpi/src/system_md.c 1113 1114 size_t os::lasterror(char *buf, size_t len) { 1115 1116 if (errno == 0) return 0; 1117 1118 const char *s = ::strerror(errno); 1119 size_t n = ::strlen(s); 1120 if (n >= len) { 1121 n = len - 1; 1122 } 1123 ::strncpy(buf, s, n); 1124 buf[n] = '\0'; 1125 return n; 1126 } 1127 1128 intx os::current_thread_id() { 1129 #ifdef __APPLE__ 1130 return (intx)::pthread_mach_thread_np(::pthread_self()); 1131 #else 1132 return (intx)::pthread_self(); 1133 #endif 1134 } 1135 int os::current_process_id() { 1136 1137 // Under the old bsd thread library, bsd gives each thread 1138 // its own process id. Because of this each thread will return 1139 // a different pid if this method were to return the result 1140 // of getpid(2). Bsd provides no api that returns the pid 1141 // of the launcher thread for the vm. This implementation 1142 // returns a unique pid, the pid of the launcher thread 1143 // that starts the vm 'process'. 1144 1145 // Under the NPTL, getpid() returns the same pid as the 1146 // launcher thread rather than a unique pid per thread. 1147 // Use gettid() if you want the old pre NPTL behaviour. 1148 1149 // if you are looking for the result of a call to getpid() that 1150 // returns a unique pid for the calling thread, then look at the 1151 // OSThread::thread_id() method in osThread_bsd.hpp file 1152 1153 return (int)(_initial_pid ? _initial_pid : getpid()); 1154 } 1155 1156 // DLL functions 1157 1158 #define JNI_LIB_PREFIX "lib" 1159 #ifdef __APPLE__ 1160 #define JNI_LIB_SUFFIX ".dylib" 1161 #else 1162 #define JNI_LIB_SUFFIX ".so" 1163 #endif 1164 1165 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1166 1167 // This must be hard coded because it's the system's temporary 1168 // directory not the java application's temp directory, ala java.io.tmpdir. 1169 #ifdef __APPLE__ 1170 // macosx has a secure per-user temporary directory 1171 char temp_path_storage[PATH_MAX]; 1172 const char* os::get_temp_directory() { 1173 static char *temp_path = NULL; 1174 if (temp_path == NULL) { 1175 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1176 if (pathSize == 0 || pathSize > PATH_MAX) { 1177 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1178 } 1179 temp_path = temp_path_storage; 1180 } 1181 return temp_path; 1182 } 1183 #else /* __APPLE__ */ 1184 const char* os::get_temp_directory() { return "/tmp"; } 1185 #endif /* __APPLE__ */ 1186 1187 static bool file_exists(const char* filename) { 1188 struct stat statbuf; 1189 if (filename == NULL || strlen(filename) == 0) { 1190 return false; 1191 } 1192 return os::stat(filename, &statbuf) == 0; 1193 } 1194 1195 bool os::dll_build_name(char* buffer, size_t buflen, 1196 const char* pname, const char* fname) { 1197 bool retval = false; 1198 // Copied from libhpi 1199 const size_t pnamelen = pname ? strlen(pname) : 0; 1200 1201 // Return error on buffer overflow. 1202 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1203 return retval; 1204 } 1205 1206 if (pnamelen == 0) { 1207 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1208 retval = true; 1209 } else if (strchr(pname, *os::path_separator()) != NULL) { 1210 int n; 1211 char** pelements = split_path(pname, &n); 1212 if (pelements == NULL) { 1213 return false; 1214 } 1215 for (int i = 0 ; i < n ; i++) { 1216 // Really shouldn't be NULL, but check can't hurt 1217 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1218 continue; // skip the empty path values 1219 } 1220 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1221 pelements[i], fname); 1222 if (file_exists(buffer)) { 1223 retval = true; 1224 break; 1225 } 1226 } 1227 // release the storage 1228 for (int i = 0 ; i < n ; i++) { 1229 if (pelements[i] != NULL) { 1230 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1231 } 1232 } 1233 if (pelements != NULL) { 1234 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1235 } 1236 } else { 1237 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1238 retval = true; 1239 } 1240 return retval; 1241 } 1242 1243 // check if addr is inside libjvm.so 1244 bool os::address_is_in_vm(address addr) { 1245 static address libjvm_base_addr; 1246 Dl_info dlinfo; 1247 1248 if (libjvm_base_addr == NULL) { 1249 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1250 libjvm_base_addr = (address)dlinfo.dli_fbase; 1251 } 1252 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1253 } 1254 1255 if (dladdr((void *)addr, &dlinfo) != 0) { 1256 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1257 } 1258 1259 return false; 1260 } 1261 1262 1263 #define MACH_MAXSYMLEN 256 1264 1265 bool os::dll_address_to_function_name(address addr, char *buf, 1266 int buflen, int *offset) { 1267 // buf is not optional, but offset is optional 1268 assert(buf != NULL, "sanity check"); 1269 1270 Dl_info dlinfo; 1271 char localbuf[MACH_MAXSYMLEN]; 1272 1273 if (dladdr((void*)addr, &dlinfo) != 0) { 1274 // see if we have a matching symbol 1275 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1276 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1277 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1278 } 1279 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1280 return true; 1281 } 1282 // no matching symbol so try for just file info 1283 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1284 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1285 buf, buflen, offset, dlinfo.dli_fname)) { 1286 return true; 1287 } 1288 } 1289 1290 // Handle non-dynamic manually: 1291 if (dlinfo.dli_fbase != NULL && 1292 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1293 dlinfo.dli_fbase)) { 1294 if (!Decoder::demangle(localbuf, buf, buflen)) { 1295 jio_snprintf(buf, buflen, "%s", localbuf); 1296 } 1297 return true; 1298 } 1299 } 1300 buf[0] = '\0'; 1301 if (offset != NULL) *offset = -1; 1302 return false; 1303 } 1304 1305 // ported from solaris version 1306 bool os::dll_address_to_library_name(address addr, char* buf, 1307 int buflen, int* offset) { 1308 // buf is not optional, but offset is optional 1309 assert(buf != NULL, "sanity check"); 1310 1311 Dl_info dlinfo; 1312 1313 if (dladdr((void*)addr, &dlinfo) != 0) { 1314 if (dlinfo.dli_fname != NULL) { 1315 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1316 } 1317 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1318 *offset = addr - (address)dlinfo.dli_fbase; 1319 } 1320 return true; 1321 } 1322 1323 buf[0] = '\0'; 1324 if (offset) *offset = -1; 1325 return false; 1326 } 1327 1328 // Loads .dll/.so and 1329 // in case of error it checks if .dll/.so was built for the 1330 // same architecture as Hotspot is running on 1331 1332 #ifdef __APPLE__ 1333 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1334 void * result= ::dlopen(filename, RTLD_LAZY); 1335 if (result != NULL) { 1336 // Successful loading 1337 return result; 1338 } 1339 1340 // Read system error message into ebuf 1341 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1342 ebuf[ebuflen-1]='\0'; 1343 1344 return NULL; 1345 } 1346 #else 1347 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1348 { 1349 void * result= ::dlopen(filename, RTLD_LAZY); 1350 if (result != NULL) { 1351 // Successful loading 1352 return result; 1353 } 1354 1355 Elf32_Ehdr elf_head; 1356 1357 // Read system error message into ebuf 1358 // It may or may not be overwritten below 1359 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1360 ebuf[ebuflen-1]='\0'; 1361 int diag_msg_max_length=ebuflen-strlen(ebuf); 1362 char* diag_msg_buf=ebuf+strlen(ebuf); 1363 1364 if (diag_msg_max_length==0) { 1365 // No more space in ebuf for additional diagnostics message 1366 return NULL; 1367 } 1368 1369 1370 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1371 1372 if (file_descriptor < 0) { 1373 // Can't open library, report dlerror() message 1374 return NULL; 1375 } 1376 1377 bool failed_to_read_elf_head= 1378 (sizeof(elf_head)!= 1379 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 1380 1381 ::close(file_descriptor); 1382 if (failed_to_read_elf_head) { 1383 // file i/o error - report dlerror() msg 1384 return NULL; 1385 } 1386 1387 typedef struct { 1388 Elf32_Half code; // Actual value as defined in elf.h 1389 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1390 char elf_class; // 32 or 64 bit 1391 char endianess; // MSB or LSB 1392 char* name; // String representation 1393 } arch_t; 1394 1395 #ifndef EM_486 1396 #define EM_486 6 /* Intel 80486 */ 1397 #endif 1398 1399 #ifndef EM_MIPS_RS3_LE 1400 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1401 #endif 1402 1403 #ifndef EM_PPC64 1404 #define EM_PPC64 21 /* PowerPC64 */ 1405 #endif 1406 1407 #ifndef EM_S390 1408 #define EM_S390 22 /* IBM System/390 */ 1409 #endif 1410 1411 #ifndef EM_IA_64 1412 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1413 #endif 1414 1415 #ifndef EM_X86_64 1416 #define EM_X86_64 62 /* AMD x86-64 */ 1417 #endif 1418 1419 static const arch_t arch_array[]={ 1420 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1421 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1422 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1423 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1424 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1425 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1426 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1427 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1428 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1429 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1430 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1431 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1432 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1433 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1434 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1435 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1436 }; 1437 1438 #if (defined IA32) 1439 static Elf32_Half running_arch_code=EM_386; 1440 #elif (defined AMD64) 1441 static Elf32_Half running_arch_code=EM_X86_64; 1442 #elif (defined IA64) 1443 static Elf32_Half running_arch_code=EM_IA_64; 1444 #elif (defined __sparc) && (defined _LP64) 1445 static Elf32_Half running_arch_code=EM_SPARCV9; 1446 #elif (defined __sparc) && (!defined _LP64) 1447 static Elf32_Half running_arch_code=EM_SPARC; 1448 #elif (defined __powerpc64__) 1449 static Elf32_Half running_arch_code=EM_PPC64; 1450 #elif (defined __powerpc__) 1451 static Elf32_Half running_arch_code=EM_PPC; 1452 #elif (defined ARM) 1453 static Elf32_Half running_arch_code=EM_ARM; 1454 #elif (defined S390) 1455 static Elf32_Half running_arch_code=EM_S390; 1456 #elif (defined ALPHA) 1457 static Elf32_Half running_arch_code=EM_ALPHA; 1458 #elif (defined MIPSEL) 1459 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1460 #elif (defined PARISC) 1461 static Elf32_Half running_arch_code=EM_PARISC; 1462 #elif (defined MIPS) 1463 static Elf32_Half running_arch_code=EM_MIPS; 1464 #elif (defined M68K) 1465 static Elf32_Half running_arch_code=EM_68K; 1466 #else 1467 #error Method os::dll_load requires that one of following is defined:\ 1468 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1469 #endif 1470 1471 // Identify compatability class for VM's architecture and library's architecture 1472 // Obtain string descriptions for architectures 1473 1474 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1475 int running_arch_index=-1; 1476 1477 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 1478 if (running_arch_code == arch_array[i].code) { 1479 running_arch_index = i; 1480 } 1481 if (lib_arch.code == arch_array[i].code) { 1482 lib_arch.compat_class = arch_array[i].compat_class; 1483 lib_arch.name = arch_array[i].name; 1484 } 1485 } 1486 1487 assert(running_arch_index != -1, 1488 "Didn't find running architecture code (running_arch_code) in arch_array"); 1489 if (running_arch_index == -1) { 1490 // Even though running architecture detection failed 1491 // we may still continue with reporting dlerror() message 1492 return NULL; 1493 } 1494 1495 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1496 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1497 return NULL; 1498 } 1499 1500 #ifndef S390 1501 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1502 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1503 return NULL; 1504 } 1505 #endif // !S390 1506 1507 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1508 if ( lib_arch.name!=NULL ) { 1509 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1510 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1511 lib_arch.name, arch_array[running_arch_index].name); 1512 } else { 1513 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1514 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1515 lib_arch.code, 1516 arch_array[running_arch_index].name); 1517 } 1518 } 1519 1520 return NULL; 1521 } 1522 #endif /* !__APPLE__ */ 1523 1524 // XXX: Do we need a lock around this as per Linux? 1525 void* os::dll_lookup(void* handle, const char* name) { 1526 return dlsym(handle, name); 1527 } 1528 1529 1530 static bool _print_ascii_file(const char* filename, outputStream* st) { 1531 int fd = ::open(filename, O_RDONLY); 1532 if (fd == -1) { 1533 return false; 1534 } 1535 1536 char buf[32]; 1537 int bytes; 1538 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1539 st->print_raw(buf, bytes); 1540 } 1541 1542 ::close(fd); 1543 1544 return true; 1545 } 1546 1547 void os::print_dll_info(outputStream *st) { 1548 st->print_cr("Dynamic libraries:"); 1549 #ifdef RTLD_DI_LINKMAP 1550 Dl_info dli; 1551 void *handle; 1552 Link_map *map; 1553 Link_map *p; 1554 1555 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1556 dli.dli_fname == NULL) { 1557 st->print_cr("Error: Cannot print dynamic libraries."); 1558 return; 1559 } 1560 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1561 if (handle == NULL) { 1562 st->print_cr("Error: Cannot print dynamic libraries."); 1563 return; 1564 } 1565 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1566 if (map == NULL) { 1567 st->print_cr("Error: Cannot print dynamic libraries."); 1568 return; 1569 } 1570 1571 while (map->l_prev != NULL) 1572 map = map->l_prev; 1573 1574 while (map != NULL) { 1575 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1576 map = map->l_next; 1577 } 1578 1579 dlclose(handle); 1580 #elif defined(__APPLE__) 1581 uint32_t count; 1582 uint32_t i; 1583 1584 count = _dyld_image_count(); 1585 for (i = 1; i < count; i++) { 1586 const char *name = _dyld_get_image_name(i); 1587 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 1588 st->print_cr(PTR_FORMAT " \t%s", slide, name); 1589 } 1590 #else 1591 st->print_cr("Error: Cannot print dynamic libraries."); 1592 #endif 1593 } 1594 1595 void os::print_os_info_brief(outputStream* st) { 1596 st->print("Bsd"); 1597 1598 os::Posix::print_uname_info(st); 1599 } 1600 1601 void os::print_os_info(outputStream* st) { 1602 st->print("OS:"); 1603 st->print("Bsd"); 1604 1605 os::Posix::print_uname_info(st); 1606 1607 os::Posix::print_rlimit_info(st); 1608 1609 os::Posix::print_load_average(st); 1610 } 1611 1612 void os::pd_print_cpu_info(outputStream* st) { 1613 // Nothing to do for now. 1614 } 1615 1616 void os::print_memory_info(outputStream* st) { 1617 1618 st->print("Memory:"); 1619 st->print(" %dk page", os::vm_page_size()>>10); 1620 1621 st->print(", physical " UINT64_FORMAT "k", 1622 os::physical_memory() >> 10); 1623 st->print("(" UINT64_FORMAT "k free)", 1624 os::available_memory() >> 10); 1625 st->cr(); 1626 1627 // meminfo 1628 st->print("\n/proc/meminfo:\n"); 1629 _print_ascii_file("/proc/meminfo", st); 1630 st->cr(); 1631 } 1632 1633 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific 1634 // but they're the same for all the bsd arch that we support 1635 // and they're the same for solaris but there's no common place to put this. 1636 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR", 1637 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG", 1638 "ILL_COPROC", "ILL_BADSTK" }; 1639 1640 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV", 1641 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES", 1642 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" }; 1643 1644 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" }; 1645 1646 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" }; 1647 1648 void os::print_siginfo(outputStream* st, void* siginfo) { 1649 st->print("siginfo:"); 1650 1651 const int buflen = 100; 1652 char buf[buflen]; 1653 siginfo_t *si = (siginfo_t*)siginfo; 1654 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen)); 1655 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) { 1656 st->print("si_errno=%s", buf); 1657 } else { 1658 st->print("si_errno=%d", si->si_errno); 1659 } 1660 const int c = si->si_code; 1661 assert(c > 0, "unexpected si_code"); 1662 switch (si->si_signo) { 1663 case SIGILL: 1664 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]); 1665 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1666 break; 1667 case SIGFPE: 1668 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]); 1669 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1670 break; 1671 case SIGSEGV: 1672 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]); 1673 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1674 break; 1675 case SIGBUS: 1676 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]); 1677 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1678 break; 1679 default: 1680 st->print(", si_code=%d", si->si_code); 1681 // no si_addr 1682 } 1683 1684 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1685 UseSharedSpaces) { 1686 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1687 if (mapinfo->is_in_shared_space(si->si_addr)) { 1688 st->print("\n\nError accessing class data sharing archive." \ 1689 " Mapped file inaccessible during execution, " \ 1690 " possible disk/network problem."); 1691 } 1692 } 1693 st->cr(); 1694 } 1695 1696 1697 static void print_signal_handler(outputStream* st, int sig, 1698 char* buf, size_t buflen); 1699 1700 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1701 st->print_cr("Signal Handlers:"); 1702 print_signal_handler(st, SIGSEGV, buf, buflen); 1703 print_signal_handler(st, SIGBUS , buf, buflen); 1704 print_signal_handler(st, SIGFPE , buf, buflen); 1705 print_signal_handler(st, SIGPIPE, buf, buflen); 1706 print_signal_handler(st, SIGXFSZ, buf, buflen); 1707 print_signal_handler(st, SIGILL , buf, buflen); 1708 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1709 print_signal_handler(st, SR_signum, buf, buflen); 1710 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1711 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1712 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1713 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1714 } 1715 1716 static char saved_jvm_path[MAXPATHLEN] = {0}; 1717 1718 // Find the full path to the current module, libjvm 1719 void os::jvm_path(char *buf, jint buflen) { 1720 // Error checking. 1721 if (buflen < MAXPATHLEN) { 1722 assert(false, "must use a large-enough buffer"); 1723 buf[0] = '\0'; 1724 return; 1725 } 1726 // Lazy resolve the path to current module. 1727 if (saved_jvm_path[0] != 0) { 1728 strcpy(buf, saved_jvm_path); 1729 return; 1730 } 1731 1732 char dli_fname[MAXPATHLEN]; 1733 bool ret = dll_address_to_library_name( 1734 CAST_FROM_FN_PTR(address, os::jvm_path), 1735 dli_fname, sizeof(dli_fname), NULL); 1736 assert(ret, "cannot locate libjvm"); 1737 char *rp = NULL; 1738 if (ret && dli_fname[0] != '\0') { 1739 rp = realpath(dli_fname, buf); 1740 } 1741 if (rp == NULL) 1742 return; 1743 1744 if (Arguments::created_by_gamma_launcher()) { 1745 // Support for the gamma launcher. Typical value for buf is 1746 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at 1747 // the right place in the string, then assume we are installed in a JDK and 1748 // we're done. Otherwise, check for a JAVA_HOME environment variable and 1749 // construct a path to the JVM being overridden. 1750 1751 const char *p = buf + strlen(buf) - 1; 1752 for (int count = 0; p > buf && count < 5; ++count) { 1753 for (--p; p > buf && *p != '/'; --p) 1754 /* empty */ ; 1755 } 1756 1757 if (strncmp(p, "/jre/lib/", 9) != 0) { 1758 // Look for JAVA_HOME in the environment. 1759 char* java_home_var = ::getenv("JAVA_HOME"); 1760 if (java_home_var != NULL && java_home_var[0] != 0) { 1761 char* jrelib_p; 1762 int len; 1763 1764 // Check the current module name "libjvm" 1765 p = strrchr(buf, '/'); 1766 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1767 1768 rp = realpath(java_home_var, buf); 1769 if (rp == NULL) 1770 return; 1771 1772 // determine if this is a legacy image or modules image 1773 // modules image doesn't have "jre" subdirectory 1774 len = strlen(buf); 1775 jrelib_p = buf + len; 1776 1777 // Add the appropriate library subdir 1778 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1779 if (0 != access(buf, F_OK)) { 1780 snprintf(jrelib_p, buflen-len, "/lib"); 1781 } 1782 1783 // Add the appropriate client or server subdir 1784 len = strlen(buf); 1785 jrelib_p = buf + len; 1786 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1787 if (0 != access(buf, F_OK)) { 1788 snprintf(jrelib_p, buflen-len, ""); 1789 } 1790 1791 // If the path exists within JAVA_HOME, add the JVM library name 1792 // to complete the path to JVM being overridden. Otherwise fallback 1793 // to the path to the current library. 1794 if (0 == access(buf, F_OK)) { 1795 // Use current module name "libjvm" 1796 len = strlen(buf); 1797 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1798 } else { 1799 // Fall back to path of current library 1800 rp = realpath(dli_fname, buf); 1801 if (rp == NULL) 1802 return; 1803 } 1804 } 1805 } 1806 } 1807 1808 strcpy(saved_jvm_path, buf); 1809 } 1810 1811 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1812 // no prefix required, not even "_" 1813 } 1814 1815 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1816 // no suffix required 1817 } 1818 1819 //////////////////////////////////////////////////////////////////////////////// 1820 // sun.misc.Signal support 1821 1822 static volatile jint sigint_count = 0; 1823 1824 static void 1825 UserHandler(int sig, void *siginfo, void *context) { 1826 // 4511530 - sem_post is serialized and handled by the manager thread. When 1827 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1828 // don't want to flood the manager thread with sem_post requests. 1829 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1830 return; 1831 1832 // Ctrl-C is pressed during error reporting, likely because the error 1833 // handler fails to abort. Let VM die immediately. 1834 if (sig == SIGINT && is_error_reported()) { 1835 os::die(); 1836 } 1837 1838 os::signal_notify(sig); 1839 } 1840 1841 void* os::user_handler() { 1842 return CAST_FROM_FN_PTR(void*, UserHandler); 1843 } 1844 1845 extern "C" { 1846 typedef void (*sa_handler_t)(int); 1847 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1848 } 1849 1850 void* os::signal(int signal_number, void* handler) { 1851 struct sigaction sigAct, oldSigAct; 1852 1853 sigfillset(&(sigAct.sa_mask)); 1854 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1855 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1856 1857 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1858 // -1 means registration failed 1859 return (void *)-1; 1860 } 1861 1862 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1863 } 1864 1865 void os::signal_raise(int signal_number) { 1866 ::raise(signal_number); 1867 } 1868 1869 /* 1870 * The following code is moved from os.cpp for making this 1871 * code platform specific, which it is by its very nature. 1872 */ 1873 1874 // Will be modified when max signal is changed to be dynamic 1875 int os::sigexitnum_pd() { 1876 return NSIG; 1877 } 1878 1879 // a counter for each possible signal value 1880 static volatile jint pending_signals[NSIG+1] = { 0 }; 1881 1882 // Bsd(POSIX) specific hand shaking semaphore. 1883 #ifdef __APPLE__ 1884 typedef semaphore_t os_semaphore_t; 1885 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1886 #define SEM_WAIT(sem) semaphore_wait(sem) 1887 #define SEM_POST(sem) semaphore_signal(sem) 1888 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1889 #else 1890 typedef sem_t os_semaphore_t; 1891 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1892 #define SEM_WAIT(sem) sem_wait(&sem) 1893 #define SEM_POST(sem) sem_post(&sem) 1894 #define SEM_DESTROY(sem) sem_destroy(&sem) 1895 #endif 1896 1897 class Semaphore : public StackObj { 1898 public: 1899 Semaphore(); 1900 ~Semaphore(); 1901 void signal(); 1902 void wait(); 1903 bool trywait(); 1904 bool timedwait(unsigned int sec, int nsec); 1905 private: 1906 jlong currenttime() const; 1907 semaphore_t _semaphore; 1908 }; 1909 1910 Semaphore::Semaphore() : _semaphore(0) { 1911 SEM_INIT(_semaphore, 0); 1912 } 1913 1914 Semaphore::~Semaphore() { 1915 SEM_DESTROY(_semaphore); 1916 } 1917 1918 void Semaphore::signal() { 1919 SEM_POST(_semaphore); 1920 } 1921 1922 void Semaphore::wait() { 1923 SEM_WAIT(_semaphore); 1924 } 1925 1926 jlong Semaphore::currenttime() const { 1927 struct timeval tv; 1928 gettimeofday(&tv, NULL); 1929 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1930 } 1931 1932 #ifdef __APPLE__ 1933 bool Semaphore::trywait() { 1934 return timedwait(0, 0); 1935 } 1936 1937 bool Semaphore::timedwait(unsigned int sec, int nsec) { 1938 kern_return_t kr = KERN_ABORTED; 1939 mach_timespec_t waitspec; 1940 waitspec.tv_sec = sec; 1941 waitspec.tv_nsec = nsec; 1942 1943 jlong starttime = currenttime(); 1944 1945 kr = semaphore_timedwait(_semaphore, waitspec); 1946 while (kr == KERN_ABORTED) { 1947 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1948 1949 jlong current = currenttime(); 1950 jlong passedtime = current - starttime; 1951 1952 if (passedtime >= totalwait) { 1953 waitspec.tv_sec = 0; 1954 waitspec.tv_nsec = 0; 1955 } else { 1956 jlong waittime = totalwait - (current - starttime); 1957 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 1958 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 1959 } 1960 1961 kr = semaphore_timedwait(_semaphore, waitspec); 1962 } 1963 1964 return kr == KERN_SUCCESS; 1965 } 1966 1967 #else 1968 1969 bool Semaphore::trywait() { 1970 return sem_trywait(&_semaphore) == 0; 1971 } 1972 1973 bool Semaphore::timedwait(unsigned int sec, int nsec) { 1974 struct timespec ts; 1975 jlong endtime = unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 1976 1977 while (1) { 1978 int result = sem_timedwait(&_semaphore, &ts); 1979 if (result == 0) { 1980 return true; 1981 } else if (errno == EINTR) { 1982 continue; 1983 } else if (errno == ETIMEDOUT) { 1984 return false; 1985 } else { 1986 return false; 1987 } 1988 } 1989 } 1990 1991 #endif // __APPLE__ 1992 1993 static os_semaphore_t sig_sem; 1994 static Semaphore sr_semaphore; 1995 1996 void os::signal_init_pd() { 1997 // Initialize signal structures 1998 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 1999 2000 // Initialize signal semaphore 2001 ::SEM_INIT(sig_sem, 0); 2002 } 2003 2004 void os::signal_notify(int sig) { 2005 Atomic::inc(&pending_signals[sig]); 2006 ::SEM_POST(sig_sem); 2007 } 2008 2009 static int check_pending_signals(bool wait) { 2010 Atomic::store(0, &sigint_count); 2011 for (;;) { 2012 for (int i = 0; i < NSIG + 1; i++) { 2013 jint n = pending_signals[i]; 2014 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2015 return i; 2016 } 2017 } 2018 if (!wait) { 2019 return -1; 2020 } 2021 JavaThread *thread = JavaThread::current(); 2022 ThreadBlockInVM tbivm(thread); 2023 2024 bool threadIsSuspended; 2025 do { 2026 thread->set_suspend_equivalent(); 2027 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2028 ::SEM_WAIT(sig_sem); 2029 2030 // were we externally suspended while we were waiting? 2031 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2032 if (threadIsSuspended) { 2033 // 2034 // The semaphore has been incremented, but while we were waiting 2035 // another thread suspended us. We don't want to continue running 2036 // while suspended because that would surprise the thread that 2037 // suspended us. 2038 // 2039 ::SEM_POST(sig_sem); 2040 2041 thread->java_suspend_self(); 2042 } 2043 } while (threadIsSuspended); 2044 } 2045 } 2046 2047 int os::signal_lookup() { 2048 return check_pending_signals(false); 2049 } 2050 2051 int os::signal_wait() { 2052 return check_pending_signals(true); 2053 } 2054 2055 //////////////////////////////////////////////////////////////////////////////// 2056 // Virtual Memory 2057 2058 int os::vm_page_size() { 2059 // Seems redundant as all get out 2060 assert(os::Bsd::page_size() != -1, "must call os::init"); 2061 return os::Bsd::page_size(); 2062 } 2063 2064 // Solaris allocates memory by pages. 2065 int os::vm_allocation_granularity() { 2066 assert(os::Bsd::page_size() != -1, "must call os::init"); 2067 return os::Bsd::page_size(); 2068 } 2069 2070 // Rationale behind this function: 2071 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2072 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2073 // samples for JITted code. Here we create private executable mapping over the code cache 2074 // and then we can use standard (well, almost, as mapping can change) way to provide 2075 // info for the reporting script by storing timestamp and location of symbol 2076 void bsd_wrap_code(char* base, size_t size) { 2077 static volatile jint cnt = 0; 2078 2079 if (!UseOprofile) { 2080 return; 2081 } 2082 2083 char buf[PATH_MAX + 1]; 2084 int num = Atomic::add(1, &cnt); 2085 2086 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2087 os::get_temp_directory(), os::current_process_id(), num); 2088 unlink(buf); 2089 2090 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2091 2092 if (fd != -1) { 2093 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2094 if (rv != (off_t)-1) { 2095 if (::write(fd, "", 1) == 1) { 2096 mmap(base, size, 2097 PROT_READ|PROT_WRITE|PROT_EXEC, 2098 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2099 } 2100 } 2101 ::close(fd); 2102 unlink(buf); 2103 } 2104 } 2105 2106 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2107 int err) { 2108 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2109 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2110 strerror(err), err); 2111 } 2112 2113 // NOTE: Bsd kernel does not really reserve the pages for us. 2114 // All it does is to check if there are enough free pages 2115 // left at the time of mmap(). This could be a potential 2116 // problem. 2117 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2118 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2119 #ifdef __OpenBSD__ 2120 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2121 if (::mprotect(addr, size, prot) == 0) { 2122 return true; 2123 } 2124 #else 2125 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2126 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2127 if (res != (uintptr_t) MAP_FAILED) { 2128 return true; 2129 } 2130 #endif 2131 2132 // Warn about any commit errors we see in non-product builds just 2133 // in case mmap() doesn't work as described on the man page. 2134 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2135 2136 return false; 2137 } 2138 2139 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2140 bool exec) { 2141 // alignment_hint is ignored on this OS 2142 return pd_commit_memory(addr, size, exec); 2143 } 2144 2145 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2146 const char* mesg) { 2147 assert(mesg != NULL, "mesg must be specified"); 2148 if (!pd_commit_memory(addr, size, exec)) { 2149 // add extra info in product mode for vm_exit_out_of_memory(): 2150 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2151 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2152 } 2153 } 2154 2155 void os::pd_commit_memory_or_exit(char* addr, size_t size, 2156 size_t alignment_hint, bool exec, 2157 const char* mesg) { 2158 // alignment_hint is ignored on this OS 2159 pd_commit_memory_or_exit(addr, size, exec, mesg); 2160 } 2161 2162 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2163 } 2164 2165 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2166 ::madvise(addr, bytes, MADV_DONTNEED); 2167 } 2168 2169 void os::numa_make_global(char *addr, size_t bytes) { 2170 } 2171 2172 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2173 } 2174 2175 bool os::numa_topology_changed() { return false; } 2176 2177 size_t os::numa_get_groups_num() { 2178 return 1; 2179 } 2180 2181 int os::numa_get_group_id() { 2182 return 0; 2183 } 2184 2185 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2186 if (size > 0) { 2187 ids[0] = 0; 2188 return 1; 2189 } 2190 return 0; 2191 } 2192 2193 bool os::get_page_info(char *start, page_info* info) { 2194 return false; 2195 } 2196 2197 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2198 return end; 2199 } 2200 2201 2202 bool os::pd_uncommit_memory(char* addr, size_t size) { 2203 #ifdef __OpenBSD__ 2204 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2205 return ::mprotect(addr, size, PROT_NONE) == 0; 2206 #else 2207 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2208 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2209 return res != (uintptr_t) MAP_FAILED; 2210 #endif 2211 } 2212 2213 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2214 return os::commit_memory(addr, size, !ExecMem); 2215 } 2216 2217 // If this is a growable mapping, remove the guard pages entirely by 2218 // munmap()ping them. If not, just call uncommit_memory(). 2219 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2220 return os::uncommit_memory(addr, size); 2221 } 2222 2223 static address _highest_vm_reserved_address = NULL; 2224 2225 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2226 // at 'requested_addr'. If there are existing memory mappings at the same 2227 // location, however, they will be overwritten. If 'fixed' is false, 2228 // 'requested_addr' is only treated as a hint, the return value may or 2229 // may not start from the requested address. Unlike Bsd mmap(), this 2230 // function returns NULL to indicate failure. 2231 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2232 char * addr; 2233 int flags; 2234 2235 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2236 if (fixed) { 2237 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2238 flags |= MAP_FIXED; 2239 } 2240 2241 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2242 // touch an uncommitted page. Otherwise, the read/write might 2243 // succeed if we have enough swap space to back the physical page. 2244 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2245 flags, -1, 0); 2246 2247 if (addr != MAP_FAILED) { 2248 // anon_mmap() should only get called during VM initialization, 2249 // don't need lock (actually we can skip locking even it can be called 2250 // from multiple threads, because _highest_vm_reserved_address is just a 2251 // hint about the upper limit of non-stack memory regions.) 2252 if ((address)addr + bytes > _highest_vm_reserved_address) { 2253 _highest_vm_reserved_address = (address)addr + bytes; 2254 } 2255 } 2256 2257 return addr == MAP_FAILED ? NULL : addr; 2258 } 2259 2260 // Don't update _highest_vm_reserved_address, because there might be memory 2261 // regions above addr + size. If so, releasing a memory region only creates 2262 // a hole in the address space, it doesn't help prevent heap-stack collision. 2263 // 2264 static int anon_munmap(char * addr, size_t size) { 2265 return ::munmap(addr, size) == 0; 2266 } 2267 2268 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2269 size_t alignment_hint) { 2270 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2271 } 2272 2273 bool os::pd_release_memory(char* addr, size_t size) { 2274 return anon_munmap(addr, size); 2275 } 2276 2277 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2278 // Bsd wants the mprotect address argument to be page aligned. 2279 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2280 2281 // According to SUSv3, mprotect() should only be used with mappings 2282 // established by mmap(), and mmap() always maps whole pages. Unaligned 2283 // 'addr' likely indicates problem in the VM (e.g. trying to change 2284 // protection of malloc'ed or statically allocated memory). Check the 2285 // caller if you hit this assert. 2286 assert(addr == bottom, "sanity check"); 2287 2288 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2289 return ::mprotect(bottom, size, prot) == 0; 2290 } 2291 2292 // Set protections specified 2293 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2294 bool is_committed) { 2295 unsigned int p = 0; 2296 switch (prot) { 2297 case MEM_PROT_NONE: p = PROT_NONE; break; 2298 case MEM_PROT_READ: p = PROT_READ; break; 2299 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2300 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2301 default: 2302 ShouldNotReachHere(); 2303 } 2304 // is_committed is unused. 2305 return bsd_mprotect(addr, bytes, p); 2306 } 2307 2308 bool os::guard_memory(char* addr, size_t size) { 2309 return bsd_mprotect(addr, size, PROT_NONE); 2310 } 2311 2312 bool os::unguard_memory(char* addr, size_t size) { 2313 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2314 } 2315 2316 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2317 return false; 2318 } 2319 2320 // Large page support 2321 2322 static size_t _large_page_size = 0; 2323 2324 void os::large_page_init() { 2325 } 2326 2327 2328 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2329 fatal("This code is not used or maintained."); 2330 2331 // "exec" is passed in but not used. Creating the shared image for 2332 // the code cache doesn't have an SHM_X executable permission to check. 2333 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2334 2335 key_t key = IPC_PRIVATE; 2336 char *addr; 2337 2338 bool warn_on_failure = UseLargePages && 2339 (!FLAG_IS_DEFAULT(UseLargePages) || 2340 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2341 ); 2342 char msg[128]; 2343 2344 // Create a large shared memory region to attach to based on size. 2345 // Currently, size is the total size of the heap 2346 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2347 if (shmid == -1) { 2348 // Possible reasons for shmget failure: 2349 // 1. shmmax is too small for Java heap. 2350 // > check shmmax value: cat /proc/sys/kernel/shmmax 2351 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2352 // 2. not enough large page memory. 2353 // > check available large pages: cat /proc/meminfo 2354 // > increase amount of large pages: 2355 // echo new_value > /proc/sys/vm/nr_hugepages 2356 // Note 1: different Bsd may use different name for this property, 2357 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2358 // Note 2: it's possible there's enough physical memory available but 2359 // they are so fragmented after a long run that they can't 2360 // coalesce into large pages. Try to reserve large pages when 2361 // the system is still "fresh". 2362 if (warn_on_failure) { 2363 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 2364 warning(msg); 2365 } 2366 return NULL; 2367 } 2368 2369 // attach to the region 2370 addr = (char*)shmat(shmid, req_addr, 0); 2371 int err = errno; 2372 2373 // Remove shmid. If shmat() is successful, the actual shared memory segment 2374 // will be deleted when it's detached by shmdt() or when the process 2375 // terminates. If shmat() is not successful this will remove the shared 2376 // segment immediately. 2377 shmctl(shmid, IPC_RMID, NULL); 2378 2379 if ((intptr_t)addr == -1) { 2380 if (warn_on_failure) { 2381 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 2382 warning(msg); 2383 } 2384 return NULL; 2385 } 2386 2387 // The memory is committed 2388 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC); 2389 2390 return addr; 2391 } 2392 2393 bool os::release_memory_special(char* base, size_t bytes) { 2394 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2395 // detaching the SHM segment will also delete it, see reserve_memory_special() 2396 int rslt = shmdt(base); 2397 if (rslt == 0) { 2398 tkr.record((address)base, bytes); 2399 return true; 2400 } else { 2401 tkr.discard(); 2402 return false; 2403 } 2404 2405 } 2406 2407 size_t os::large_page_size() { 2408 return _large_page_size; 2409 } 2410 2411 // HugeTLBFS allows application to commit large page memory on demand; 2412 // with SysV SHM the entire memory region must be allocated as shared 2413 // memory. 2414 bool os::can_commit_large_page_memory() { 2415 return UseHugeTLBFS; 2416 } 2417 2418 bool os::can_execute_large_page_memory() { 2419 return UseHugeTLBFS; 2420 } 2421 2422 // Reserve memory at an arbitrary address, only if that area is 2423 // available (and not reserved for something else). 2424 2425 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2426 const int max_tries = 10; 2427 char* base[max_tries]; 2428 size_t size[max_tries]; 2429 const size_t gap = 0x000000; 2430 2431 // Assert only that the size is a multiple of the page size, since 2432 // that's all that mmap requires, and since that's all we really know 2433 // about at this low abstraction level. If we need higher alignment, 2434 // we can either pass an alignment to this method or verify alignment 2435 // in one of the methods further up the call chain. See bug 5044738. 2436 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2437 2438 // Repeatedly allocate blocks until the block is allocated at the 2439 // right spot. Give up after max_tries. Note that reserve_memory() will 2440 // automatically update _highest_vm_reserved_address if the call is 2441 // successful. The variable tracks the highest memory address every reserved 2442 // by JVM. It is used to detect heap-stack collision if running with 2443 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2444 // space than needed, it could confuse the collision detecting code. To 2445 // solve the problem, save current _highest_vm_reserved_address and 2446 // calculate the correct value before return. 2447 address old_highest = _highest_vm_reserved_address; 2448 2449 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2450 // if kernel honors the hint then we can return immediately. 2451 char * addr = anon_mmap(requested_addr, bytes, false); 2452 if (addr == requested_addr) { 2453 return requested_addr; 2454 } 2455 2456 if (addr != NULL) { 2457 // mmap() is successful but it fails to reserve at the requested address 2458 anon_munmap(addr, bytes); 2459 } 2460 2461 int i; 2462 for (i = 0; i < max_tries; ++i) { 2463 base[i] = reserve_memory(bytes); 2464 2465 if (base[i] != NULL) { 2466 // Is this the block we wanted? 2467 if (base[i] == requested_addr) { 2468 size[i] = bytes; 2469 break; 2470 } 2471 2472 // Does this overlap the block we wanted? Give back the overlapped 2473 // parts and try again. 2474 2475 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2476 if (top_overlap >= 0 && top_overlap < bytes) { 2477 unmap_memory(base[i], top_overlap); 2478 base[i] += top_overlap; 2479 size[i] = bytes - top_overlap; 2480 } else { 2481 size_t bottom_overlap = base[i] + bytes - requested_addr; 2482 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2483 unmap_memory(requested_addr, bottom_overlap); 2484 size[i] = bytes - bottom_overlap; 2485 } else { 2486 size[i] = bytes; 2487 } 2488 } 2489 } 2490 } 2491 2492 // Give back the unused reserved pieces. 2493 2494 for (int j = 0; j < i; ++j) { 2495 if (base[j] != NULL) { 2496 unmap_memory(base[j], size[j]); 2497 } 2498 } 2499 2500 if (i < max_tries) { 2501 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2502 return requested_addr; 2503 } else { 2504 _highest_vm_reserved_address = old_highest; 2505 return NULL; 2506 } 2507 } 2508 2509 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2510 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2511 } 2512 2513 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation. 2514 // Solaris uses poll(), bsd uses park(). 2515 // Poll() is likely a better choice, assuming that Thread.interrupt() 2516 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with 2517 // SIGSEGV, see 4355769. 2518 2519 int os::sleep(Thread* thread, jlong millis, bool interruptible) { 2520 assert(thread == Thread::current(), "thread consistency check"); 2521 2522 ParkEvent * const slp = thread->_SleepEvent ; 2523 slp->reset() ; 2524 OrderAccess::fence() ; 2525 2526 if (interruptible) { 2527 jlong prevtime = javaTimeNanos(); 2528 2529 for (;;) { 2530 if (os::is_interrupted(thread, true)) { 2531 return OS_INTRPT; 2532 } 2533 2534 jlong newtime = javaTimeNanos(); 2535 2536 if (newtime - prevtime < 0) { 2537 // time moving backwards, should only happen if no monotonic clock 2538 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2539 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2540 } else { 2541 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2542 } 2543 2544 if(millis <= 0) { 2545 return OS_OK; 2546 } 2547 2548 prevtime = newtime; 2549 2550 { 2551 assert(thread->is_Java_thread(), "sanity check"); 2552 JavaThread *jt = (JavaThread *) thread; 2553 ThreadBlockInVM tbivm(jt); 2554 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 2555 2556 jt->set_suspend_equivalent(); 2557 // cleared by handle_special_suspend_equivalent_condition() or 2558 // java_suspend_self() via check_and_wait_while_suspended() 2559 2560 slp->park(millis); 2561 2562 // were we externally suspended while we were waiting? 2563 jt->check_and_wait_while_suspended(); 2564 } 2565 } 2566 } else { 2567 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 2568 jlong prevtime = javaTimeNanos(); 2569 2570 for (;;) { 2571 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 2572 // the 1st iteration ... 2573 jlong newtime = javaTimeNanos(); 2574 2575 if (newtime - prevtime < 0) { 2576 // time moving backwards, should only happen if no monotonic clock 2577 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2578 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2579 } else { 2580 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2581 } 2582 2583 if(millis <= 0) break ; 2584 2585 prevtime = newtime; 2586 slp->park(millis); 2587 } 2588 return OS_OK ; 2589 } 2590 } 2591 2592 int os::naked_sleep() { 2593 // %% make the sleep time an integer flag. for now use 1 millisec. 2594 return os::sleep(Thread::current(), 1, false); 2595 } 2596 2597 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2598 void os::infinite_sleep() { 2599 while (true) { // sleep forever ... 2600 ::sleep(100); // ... 100 seconds at a time 2601 } 2602 } 2603 2604 // Used to convert frequent JVM_Yield() to nops 2605 bool os::dont_yield() { 2606 return DontYieldALot; 2607 } 2608 2609 void os::yield() { 2610 sched_yield(); 2611 } 2612 2613 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 2614 2615 void os::yield_all(int attempts) { 2616 // Yields to all threads, including threads with lower priorities 2617 // Threads on Bsd are all with same priority. The Solaris style 2618 // os::yield_all() with nanosleep(1ms) is not necessary. 2619 sched_yield(); 2620 } 2621 2622 // Called from the tight loops to possibly influence time-sharing heuristics 2623 void os::loop_breaker(int attempts) { 2624 os::yield_all(attempts); 2625 } 2626 2627 //////////////////////////////////////////////////////////////////////////////// 2628 // thread priority support 2629 2630 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2631 // only supports dynamic priority, static priority must be zero. For real-time 2632 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2633 // However, for large multi-threaded applications, SCHED_RR is not only slower 2634 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2635 // of 5 runs - Sep 2005). 2636 // 2637 // The following code actually changes the niceness of kernel-thread/LWP. It 2638 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2639 // not the entire user process, and user level threads are 1:1 mapped to kernel 2640 // threads. It has always been the case, but could change in the future. For 2641 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2642 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2643 2644 #if !defined(__APPLE__) 2645 int os::java_to_os_priority[CriticalPriority + 1] = { 2646 19, // 0 Entry should never be used 2647 2648 0, // 1 MinPriority 2649 3, // 2 2650 6, // 3 2651 2652 10, // 4 2653 15, // 5 NormPriority 2654 18, // 6 2655 2656 21, // 7 2657 25, // 8 2658 28, // 9 NearMaxPriority 2659 2660 31, // 10 MaxPriority 2661 2662 31 // 11 CriticalPriority 2663 }; 2664 #else 2665 /* Using Mach high-level priority assignments */ 2666 int os::java_to_os_priority[CriticalPriority + 1] = { 2667 0, // 0 Entry should never be used (MINPRI_USER) 2668 2669 27, // 1 MinPriority 2670 28, // 2 2671 29, // 3 2672 2673 30, // 4 2674 31, // 5 NormPriority (BASEPRI_DEFAULT) 2675 32, // 6 2676 2677 33, // 7 2678 34, // 8 2679 35, // 9 NearMaxPriority 2680 2681 36, // 10 MaxPriority 2682 2683 36 // 11 CriticalPriority 2684 }; 2685 #endif 2686 2687 static int prio_init() { 2688 if (ThreadPriorityPolicy == 1) { 2689 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2690 // if effective uid is not root. Perhaps, a more elegant way of doing 2691 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2692 if (geteuid() != 0) { 2693 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2694 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2695 } 2696 ThreadPriorityPolicy = 0; 2697 } 2698 } 2699 if (UseCriticalJavaThreadPriority) { 2700 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2701 } 2702 return 0; 2703 } 2704 2705 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2706 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 2707 2708 #ifdef __OpenBSD__ 2709 // OpenBSD pthread_setprio starves low priority threads 2710 return OS_OK; 2711 #elif defined(__FreeBSD__) 2712 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2713 #elif defined(__APPLE__) || defined(__NetBSD__) 2714 struct sched_param sp; 2715 int policy; 2716 pthread_t self = pthread_self(); 2717 2718 if (pthread_getschedparam(self, &policy, &sp) != 0) 2719 return OS_ERR; 2720 2721 sp.sched_priority = newpri; 2722 if (pthread_setschedparam(self, policy, &sp) != 0) 2723 return OS_ERR; 2724 2725 return OS_OK; 2726 #else 2727 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2728 return (ret == 0) ? OS_OK : OS_ERR; 2729 #endif 2730 } 2731 2732 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2733 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 2734 *priority_ptr = java_to_os_priority[NormPriority]; 2735 return OS_OK; 2736 } 2737 2738 errno = 0; 2739 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2740 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2741 #elif defined(__APPLE__) || defined(__NetBSD__) 2742 int policy; 2743 struct sched_param sp; 2744 2745 pthread_getschedparam(pthread_self(), &policy, &sp); 2746 *priority_ptr = sp.sched_priority; 2747 #else 2748 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2749 #endif 2750 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2751 } 2752 2753 // Hint to the underlying OS that a task switch would not be good. 2754 // Void return because it's a hint and can fail. 2755 void os::hint_no_preempt() {} 2756 2757 //////////////////////////////////////////////////////////////////////////////// 2758 // suspend/resume support 2759 2760 // the low-level signal-based suspend/resume support is a remnant from the 2761 // old VM-suspension that used to be for java-suspension, safepoints etc, 2762 // within hotspot. Now there is a single use-case for this: 2763 // - calling get_thread_pc() on the VMThread by the flat-profiler task 2764 // that runs in the watcher thread. 2765 // The remaining code is greatly simplified from the more general suspension 2766 // code that used to be used. 2767 // 2768 // The protocol is quite simple: 2769 // - suspend: 2770 // - sends a signal to the target thread 2771 // - polls the suspend state of the osthread using a yield loop 2772 // - target thread signal handler (SR_handler) sets suspend state 2773 // and blocks in sigsuspend until continued 2774 // - resume: 2775 // - sets target osthread state to continue 2776 // - sends signal to end the sigsuspend loop in the SR_handler 2777 // 2778 // Note that the SR_lock plays no role in this suspend/resume protocol. 2779 // 2780 2781 static void resume_clear_context(OSThread *osthread) { 2782 osthread->set_ucontext(NULL); 2783 osthread->set_siginfo(NULL); 2784 } 2785 2786 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2787 osthread->set_ucontext(context); 2788 osthread->set_siginfo(siginfo); 2789 } 2790 2791 // 2792 // Handler function invoked when a thread's execution is suspended or 2793 // resumed. We have to be careful that only async-safe functions are 2794 // called here (Note: most pthread functions are not async safe and 2795 // should be avoided.) 2796 // 2797 // Note: sigwait() is a more natural fit than sigsuspend() from an 2798 // interface point of view, but sigwait() prevents the signal hander 2799 // from being run. libpthread would get very confused by not having 2800 // its signal handlers run and prevents sigwait()'s use with the 2801 // mutex granting granting signal. 2802 // 2803 // Currently only ever called on the VMThread or JavaThread 2804 // 2805 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2806 // Save and restore errno to avoid confusing native code with EINTR 2807 // after sigsuspend. 2808 int old_errno = errno; 2809 2810 Thread* thread = Thread::current(); 2811 OSThread* osthread = thread->osthread(); 2812 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2813 2814 os::SuspendResume::State current = osthread->sr.state(); 2815 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2816 suspend_save_context(osthread, siginfo, context); 2817 2818 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2819 os::SuspendResume::State state = osthread->sr.suspended(); 2820 if (state == os::SuspendResume::SR_SUSPENDED) { 2821 sigset_t suspend_set; // signals for sigsuspend() 2822 2823 // get current set of blocked signals and unblock resume signal 2824 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2825 sigdelset(&suspend_set, SR_signum); 2826 2827 sr_semaphore.signal(); 2828 // wait here until we are resumed 2829 while (1) { 2830 sigsuspend(&suspend_set); 2831 2832 os::SuspendResume::State result = osthread->sr.running(); 2833 if (result == os::SuspendResume::SR_RUNNING) { 2834 sr_semaphore.signal(); 2835 break; 2836 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2837 ShouldNotReachHere(); 2838 } 2839 } 2840 2841 } else if (state == os::SuspendResume::SR_RUNNING) { 2842 // request was cancelled, continue 2843 } else { 2844 ShouldNotReachHere(); 2845 } 2846 2847 resume_clear_context(osthread); 2848 } else if (current == os::SuspendResume::SR_RUNNING) { 2849 // request was cancelled, continue 2850 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2851 // ignore 2852 } else { 2853 // ignore 2854 } 2855 2856 errno = old_errno; 2857 } 2858 2859 2860 static int SR_initialize() { 2861 struct sigaction act; 2862 char *s; 2863 /* Get signal number to use for suspend/resume */ 2864 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2865 int sig = ::strtol(s, 0, 10); 2866 if (sig > 0 || sig < NSIG) { 2867 SR_signum = sig; 2868 } 2869 } 2870 2871 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2872 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2873 2874 sigemptyset(&SR_sigset); 2875 sigaddset(&SR_sigset, SR_signum); 2876 2877 /* Set up signal handler for suspend/resume */ 2878 act.sa_flags = SA_RESTART|SA_SIGINFO; 2879 act.sa_handler = (void (*)(int)) SR_handler; 2880 2881 // SR_signum is blocked by default. 2882 // 4528190 - We also need to block pthread restart signal (32 on all 2883 // supported Bsd platforms). Note that BsdThreads need to block 2884 // this signal for all threads to work properly. So we don't have 2885 // to use hard-coded signal number when setting up the mask. 2886 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2887 2888 if (sigaction(SR_signum, &act, 0) == -1) { 2889 return -1; 2890 } 2891 2892 // Save signal flag 2893 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2894 return 0; 2895 } 2896 2897 static int sr_notify(OSThread* osthread) { 2898 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2899 assert_status(status == 0, status, "pthread_kill"); 2900 return status; 2901 } 2902 2903 // "Randomly" selected value for how long we want to spin 2904 // before bailing out on suspending a thread, also how often 2905 // we send a signal to a thread we want to resume 2906 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2907 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2908 2909 // returns true on success and false on error - really an error is fatal 2910 // but this seems the normal response to library errors 2911 static bool do_suspend(OSThread* osthread) { 2912 assert(osthread->sr.is_running(), "thread should be running"); 2913 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2914 2915 // mark as suspended and send signal 2916 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2917 // failed to switch, state wasn't running? 2918 ShouldNotReachHere(); 2919 return false; 2920 } 2921 2922 if (sr_notify(osthread) != 0) { 2923 ShouldNotReachHere(); 2924 } 2925 2926 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2927 while (true) { 2928 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2929 break; 2930 } else { 2931 // timeout 2932 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2933 if (cancelled == os::SuspendResume::SR_RUNNING) { 2934 return false; 2935 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2936 // make sure that we consume the signal on the semaphore as well 2937 sr_semaphore.wait(); 2938 break; 2939 } else { 2940 ShouldNotReachHere(); 2941 return false; 2942 } 2943 } 2944 } 2945 2946 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2947 return true; 2948 } 2949 2950 static void do_resume(OSThread* osthread) { 2951 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2952 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2953 2954 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2955 // failed to switch to WAKEUP_REQUEST 2956 ShouldNotReachHere(); 2957 return; 2958 } 2959 2960 while (true) { 2961 if (sr_notify(osthread) == 0) { 2962 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2963 if (osthread->sr.is_running()) { 2964 return; 2965 } 2966 } 2967 } else { 2968 ShouldNotReachHere(); 2969 } 2970 } 2971 2972 guarantee(osthread->sr.is_running(), "Must be running!"); 2973 } 2974 2975 //////////////////////////////////////////////////////////////////////////////// 2976 // interrupt support 2977 2978 void os::interrupt(Thread* thread) { 2979 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 2980 "possibility of dangling Thread pointer"); 2981 2982 OSThread* osthread = thread->osthread(); 2983 2984 if (!osthread->interrupted()) { 2985 osthread->set_interrupted(true); 2986 // More than one thread can get here with the same value of osthread, 2987 // resulting in multiple notifications. We do, however, want the store 2988 // to interrupted() to be visible to other threads before we execute unpark(). 2989 OrderAccess::fence(); 2990 ParkEvent * const slp = thread->_SleepEvent ; 2991 if (slp != NULL) slp->unpark() ; 2992 } 2993 2994 // For JSR166. Unpark even if interrupt status already was set 2995 if (thread->is_Java_thread()) 2996 ((JavaThread*)thread)->parker()->unpark(); 2997 2998 ParkEvent * ev = thread->_ParkEvent ; 2999 if (ev != NULL) ev->unpark() ; 3000 3001 } 3002 3003 bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 3004 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3005 "possibility of dangling Thread pointer"); 3006 3007 OSThread* osthread = thread->osthread(); 3008 3009 bool interrupted = osthread->interrupted(); 3010 3011 if (interrupted && clear_interrupted) { 3012 osthread->set_interrupted(false); 3013 // consider thread->_SleepEvent->reset() ... optional optimization 3014 } 3015 3016 return interrupted; 3017 } 3018 3019 /////////////////////////////////////////////////////////////////////////////////// 3020 // signal handling (except suspend/resume) 3021 3022 // This routine may be used by user applications as a "hook" to catch signals. 3023 // The user-defined signal handler must pass unrecognized signals to this 3024 // routine, and if it returns true (non-zero), then the signal handler must 3025 // return immediately. If the flag "abort_if_unrecognized" is true, then this 3026 // routine will never retun false (zero), but instead will execute a VM panic 3027 // routine kill the process. 3028 // 3029 // If this routine returns false, it is OK to call it again. This allows 3030 // the user-defined signal handler to perform checks either before or after 3031 // the VM performs its own checks. Naturally, the user code would be making 3032 // a serious error if it tried to handle an exception (such as a null check 3033 // or breakpoint) that the VM was generating for its own correct operation. 3034 // 3035 // This routine may recognize any of the following kinds of signals: 3036 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 3037 // It should be consulted by handlers for any of those signals. 3038 // 3039 // The caller of this routine must pass in the three arguments supplied 3040 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 3041 // field of the structure passed to sigaction(). This routine assumes that 3042 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 3043 // 3044 // Note that the VM will print warnings if it detects conflicting signal 3045 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 3046 // 3047 extern "C" JNIEXPORT int 3048 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 3049 void* ucontext, int abort_if_unrecognized); 3050 3051 void signalHandler(int sig, siginfo_t* info, void* uc) { 3052 assert(info != NULL && uc != NULL, "it must be old kernel"); 3053 int orig_errno = errno; // Preserve errno value over signal handler. 3054 JVM_handle_bsd_signal(sig, info, uc, true); 3055 errno = orig_errno; 3056 } 3057 3058 3059 // This boolean allows users to forward their own non-matching signals 3060 // to JVM_handle_bsd_signal, harmlessly. 3061 bool os::Bsd::signal_handlers_are_installed = false; 3062 3063 // For signal-chaining 3064 struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3065 unsigned int os::Bsd::sigs = 0; 3066 bool os::Bsd::libjsig_is_loaded = false; 3067 typedef struct sigaction *(*get_signal_t)(int); 3068 get_signal_t os::Bsd::get_signal_action = NULL; 3069 3070 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3071 struct sigaction *actp = NULL; 3072 3073 if (libjsig_is_loaded) { 3074 // Retrieve the old signal handler from libjsig 3075 actp = (*get_signal_action)(sig); 3076 } 3077 if (actp == NULL) { 3078 // Retrieve the preinstalled signal handler from jvm 3079 actp = get_preinstalled_handler(sig); 3080 } 3081 3082 return actp; 3083 } 3084 3085 static bool call_chained_handler(struct sigaction *actp, int sig, 3086 siginfo_t *siginfo, void *context) { 3087 // Call the old signal handler 3088 if (actp->sa_handler == SIG_DFL) { 3089 // It's more reasonable to let jvm treat it as an unexpected exception 3090 // instead of taking the default action. 3091 return false; 3092 } else if (actp->sa_handler != SIG_IGN) { 3093 if ((actp->sa_flags & SA_NODEFER) == 0) { 3094 // automaticlly block the signal 3095 sigaddset(&(actp->sa_mask), sig); 3096 } 3097 3098 sa_handler_t hand; 3099 sa_sigaction_t sa; 3100 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3101 // retrieve the chained handler 3102 if (siginfo_flag_set) { 3103 sa = actp->sa_sigaction; 3104 } else { 3105 hand = actp->sa_handler; 3106 } 3107 3108 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3109 actp->sa_handler = SIG_DFL; 3110 } 3111 3112 // try to honor the signal mask 3113 sigset_t oset; 3114 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3115 3116 // call into the chained handler 3117 if (siginfo_flag_set) { 3118 (*sa)(sig, siginfo, context); 3119 } else { 3120 (*hand)(sig); 3121 } 3122 3123 // restore the signal mask 3124 pthread_sigmask(SIG_SETMASK, &oset, 0); 3125 } 3126 // Tell jvm's signal handler the signal is taken care of. 3127 return true; 3128 } 3129 3130 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3131 bool chained = false; 3132 // signal-chaining 3133 if (UseSignalChaining) { 3134 struct sigaction *actp = get_chained_signal_action(sig); 3135 if (actp != NULL) { 3136 chained = call_chained_handler(actp, sig, siginfo, context); 3137 } 3138 } 3139 return chained; 3140 } 3141 3142 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3143 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 3144 return &sigact[sig]; 3145 } 3146 return NULL; 3147 } 3148 3149 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3150 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3151 sigact[sig] = oldAct; 3152 sigs |= (unsigned int)1 << sig; 3153 } 3154 3155 // for diagnostic 3156 int os::Bsd::sigflags[MAXSIGNUM]; 3157 3158 int os::Bsd::get_our_sigflags(int sig) { 3159 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3160 return sigflags[sig]; 3161 } 3162 3163 void os::Bsd::set_our_sigflags(int sig, int flags) { 3164 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3165 sigflags[sig] = flags; 3166 } 3167 3168 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3169 // Check for overwrite. 3170 struct sigaction oldAct; 3171 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3172 3173 void* oldhand = oldAct.sa_sigaction 3174 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3175 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3176 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3177 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3178 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3179 if (AllowUserSignalHandlers || !set_installed) { 3180 // Do not overwrite; user takes responsibility to forward to us. 3181 return; 3182 } else if (UseSignalChaining) { 3183 // save the old handler in jvm 3184 save_preinstalled_handler(sig, oldAct); 3185 // libjsig also interposes the sigaction() call below and saves the 3186 // old sigaction on it own. 3187 } else { 3188 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3189 "%#lx for signal %d.", (long)oldhand, sig)); 3190 } 3191 } 3192 3193 struct sigaction sigAct; 3194 sigfillset(&(sigAct.sa_mask)); 3195 sigAct.sa_handler = SIG_DFL; 3196 if (!set_installed) { 3197 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3198 } else { 3199 sigAct.sa_sigaction = signalHandler; 3200 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3201 } 3202 #if __APPLE__ 3203 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3204 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3205 // if the signal handler declares it will handle it on alternate stack. 3206 // Notice we only declare we will handle it on alt stack, but we are not 3207 // actually going to use real alt stack - this is just a workaround. 3208 // Please see ux_exception.c, method catch_mach_exception_raise for details 3209 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3210 if (sig == SIGSEGV) { 3211 sigAct.sa_flags |= SA_ONSTACK; 3212 } 3213 #endif 3214 3215 // Save flags, which are set by ours 3216 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3217 sigflags[sig] = sigAct.sa_flags; 3218 3219 int ret = sigaction(sig, &sigAct, &oldAct); 3220 assert(ret == 0, "check"); 3221 3222 void* oldhand2 = oldAct.sa_sigaction 3223 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3224 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3225 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3226 } 3227 3228 // install signal handlers for signals that HotSpot needs to 3229 // handle in order to support Java-level exception handling. 3230 3231 void os::Bsd::install_signal_handlers() { 3232 if (!signal_handlers_are_installed) { 3233 signal_handlers_are_installed = true; 3234 3235 // signal-chaining 3236 typedef void (*signal_setting_t)(); 3237 signal_setting_t begin_signal_setting = NULL; 3238 signal_setting_t end_signal_setting = NULL; 3239 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3240 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3241 if (begin_signal_setting != NULL) { 3242 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3243 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3244 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3245 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3246 libjsig_is_loaded = true; 3247 assert(UseSignalChaining, "should enable signal-chaining"); 3248 } 3249 if (libjsig_is_loaded) { 3250 // Tell libjsig jvm is setting signal handlers 3251 (*begin_signal_setting)(); 3252 } 3253 3254 set_signal_handler(SIGSEGV, true); 3255 set_signal_handler(SIGPIPE, true); 3256 set_signal_handler(SIGBUS, true); 3257 set_signal_handler(SIGILL, true); 3258 set_signal_handler(SIGFPE, true); 3259 set_signal_handler(SIGXFSZ, true); 3260 3261 #if defined(__APPLE__) 3262 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3263 // signals caught and handled by the JVM. To work around this, we reset the mach task 3264 // signal handler that's placed on our process by CrashReporter. This disables 3265 // CrashReporter-based reporting. 3266 // 3267 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3268 // on caught fatal signals. 3269 // 3270 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3271 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3272 // exception handling, while leaving the standard BSD signal handlers functional. 3273 kern_return_t kr; 3274 kr = task_set_exception_ports(mach_task_self(), 3275 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3276 MACH_PORT_NULL, 3277 EXCEPTION_STATE_IDENTITY, 3278 MACHINE_THREAD_STATE); 3279 3280 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3281 #endif 3282 3283 if (libjsig_is_loaded) { 3284 // Tell libjsig jvm finishes setting signal handlers 3285 (*end_signal_setting)(); 3286 } 3287 3288 // We don't activate signal checker if libjsig is in place, we trust ourselves 3289 // and if UserSignalHandler is installed all bets are off 3290 if (CheckJNICalls) { 3291 if (libjsig_is_loaded) { 3292 if (PrintJNIResolving) { 3293 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3294 } 3295 check_signals = false; 3296 } 3297 if (AllowUserSignalHandlers) { 3298 if (PrintJNIResolving) { 3299 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3300 } 3301 check_signals = false; 3302 } 3303 } 3304 } 3305 } 3306 3307 3308 ///// 3309 // glibc on Bsd platform uses non-documented flag 3310 // to indicate, that some special sort of signal 3311 // trampoline is used. 3312 // We will never set this flag, and we should 3313 // ignore this flag in our diagnostic 3314 #ifdef SIGNIFICANT_SIGNAL_MASK 3315 #undef SIGNIFICANT_SIGNAL_MASK 3316 #endif 3317 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3318 3319 static const char* get_signal_handler_name(address handler, 3320 char* buf, int buflen) { 3321 int offset; 3322 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3323 if (found) { 3324 // skip directory names 3325 const char *p1, *p2; 3326 p1 = buf; 3327 size_t len = strlen(os::file_separator()); 3328 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3329 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3330 } else { 3331 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3332 } 3333 return buf; 3334 } 3335 3336 static void print_signal_handler(outputStream* st, int sig, 3337 char* buf, size_t buflen) { 3338 struct sigaction sa; 3339 3340 sigaction(sig, NULL, &sa); 3341 3342 // See comment for SIGNIFICANT_SIGNAL_MASK define 3343 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3344 3345 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3346 3347 address handler = (sa.sa_flags & SA_SIGINFO) 3348 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3349 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3350 3351 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3352 st->print("SIG_DFL"); 3353 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3354 st->print("SIG_IGN"); 3355 } else { 3356 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3357 } 3358 3359 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask); 3360 3361 address rh = VMError::get_resetted_sighandler(sig); 3362 // May be, handler was resetted by VMError? 3363 if(rh != NULL) { 3364 handler = rh; 3365 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3366 } 3367 3368 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags); 3369 3370 // Check: is it our handler? 3371 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3372 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3373 // It is our signal handler 3374 // check for flags, reset system-used one! 3375 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3376 st->print( 3377 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3378 os::Bsd::get_our_sigflags(sig)); 3379 } 3380 } 3381 st->cr(); 3382 } 3383 3384 3385 #define DO_SIGNAL_CHECK(sig) \ 3386 if (!sigismember(&check_signal_done, sig)) \ 3387 os::Bsd::check_signal_handler(sig) 3388 3389 // This method is a periodic task to check for misbehaving JNI applications 3390 // under CheckJNI, we can add any periodic checks here 3391 3392 void os::run_periodic_checks() { 3393 3394 if (check_signals == false) return; 3395 3396 // SEGV and BUS if overridden could potentially prevent 3397 // generation of hs*.log in the event of a crash, debugging 3398 // such a case can be very challenging, so we absolutely 3399 // check the following for a good measure: 3400 DO_SIGNAL_CHECK(SIGSEGV); 3401 DO_SIGNAL_CHECK(SIGILL); 3402 DO_SIGNAL_CHECK(SIGFPE); 3403 DO_SIGNAL_CHECK(SIGBUS); 3404 DO_SIGNAL_CHECK(SIGPIPE); 3405 DO_SIGNAL_CHECK(SIGXFSZ); 3406 3407 3408 // ReduceSignalUsage allows the user to override these handlers 3409 // see comments at the very top and jvm_solaris.h 3410 if (!ReduceSignalUsage) { 3411 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3412 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3413 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3414 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3415 } 3416 3417 DO_SIGNAL_CHECK(SR_signum); 3418 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3419 } 3420 3421 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3422 3423 static os_sigaction_t os_sigaction = NULL; 3424 3425 void os::Bsd::check_signal_handler(int sig) { 3426 char buf[O_BUFLEN]; 3427 address jvmHandler = NULL; 3428 3429 3430 struct sigaction act; 3431 if (os_sigaction == NULL) { 3432 // only trust the default sigaction, in case it has been interposed 3433 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3434 if (os_sigaction == NULL) return; 3435 } 3436 3437 os_sigaction(sig, (struct sigaction*)NULL, &act); 3438 3439 3440 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3441 3442 address thisHandler = (act.sa_flags & SA_SIGINFO) 3443 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3444 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 3445 3446 3447 switch(sig) { 3448 case SIGSEGV: 3449 case SIGBUS: 3450 case SIGFPE: 3451 case SIGPIPE: 3452 case SIGILL: 3453 case SIGXFSZ: 3454 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3455 break; 3456 3457 case SHUTDOWN1_SIGNAL: 3458 case SHUTDOWN2_SIGNAL: 3459 case SHUTDOWN3_SIGNAL: 3460 case BREAK_SIGNAL: 3461 jvmHandler = (address)user_handler(); 3462 break; 3463 3464 case INTERRUPT_SIGNAL: 3465 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3466 break; 3467 3468 default: 3469 if (sig == SR_signum) { 3470 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3471 } else { 3472 return; 3473 } 3474 break; 3475 } 3476 3477 if (thisHandler != jvmHandler) { 3478 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3479 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3480 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3481 // No need to check this sig any longer 3482 sigaddset(&check_signal_done, sig); 3483 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3484 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3485 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3486 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3487 // No need to check this sig any longer 3488 sigaddset(&check_signal_done, sig); 3489 } 3490 3491 // Dump all the signal 3492 if (sigismember(&check_signal_done, sig)) { 3493 print_signal_handlers(tty, buf, O_BUFLEN); 3494 } 3495 } 3496 3497 extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3498 3499 extern bool signal_name(int signo, char* buf, size_t len); 3500 3501 const char* os::exception_name(int exception_code, char* buf, size_t size) { 3502 if (0 < exception_code && exception_code <= SIGRTMAX) { 3503 // signal 3504 if (!signal_name(exception_code, buf, size)) { 3505 jio_snprintf(buf, size, "SIG%d", exception_code); 3506 } 3507 return buf; 3508 } else { 3509 return NULL; 3510 } 3511 } 3512 3513 // this is called _before_ the most of global arguments have been parsed 3514 void os::init(void) { 3515 char dummy; /* used to get a guess on initial stack address */ 3516 // first_hrtime = gethrtime(); 3517 3518 // With BsdThreads the JavaMain thread pid (primordial thread) 3519 // is different than the pid of the java launcher thread. 3520 // So, on Bsd, the launcher thread pid is passed to the VM 3521 // via the sun.java.launcher.pid property. 3522 // Use this property instead of getpid() if it was correctly passed. 3523 // See bug 6351349. 3524 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3525 3526 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3527 3528 clock_tics_per_sec = CLK_TCK; 3529 3530 init_random(1234567); 3531 3532 ThreadCritical::initialize(); 3533 3534 Bsd::set_page_size(getpagesize()); 3535 if (Bsd::page_size() == -1) { 3536 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3537 strerror(errno))); 3538 } 3539 init_page_sizes((size_t) Bsd::page_size()); 3540 3541 Bsd::initialize_system_info(); 3542 3543 // main_thread points to the aboriginal thread 3544 Bsd::_main_thread = pthread_self(); 3545 3546 Bsd::clock_init(); 3547 initial_time_count = os::elapsed_counter(); 3548 3549 #ifdef __APPLE__ 3550 // XXXDARWIN 3551 // Work around the unaligned VM callbacks in hotspot's 3552 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3553 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3554 // alignment when doing symbol lookup. To work around this, we force early 3555 // binding of all symbols now, thus binding when alignment is known-good. 3556 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3557 #endif 3558 } 3559 3560 // To install functions for atexit system call 3561 extern "C" { 3562 static void perfMemory_exit_helper() { 3563 perfMemory_exit(); 3564 } 3565 } 3566 3567 // this is called _after_ the global arguments have been parsed 3568 jint os::init_2(void) 3569 { 3570 // Allocate a single page and mark it as readable for safepoint polling 3571 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3572 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 3573 3574 os::set_polling_page( polling_page ); 3575 3576 #ifndef PRODUCT 3577 if(Verbose && PrintMiscellaneous) 3578 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3579 #endif 3580 3581 if (!UseMembar) { 3582 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3583 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3584 os::set_memory_serialize_page( mem_serialize_page ); 3585 3586 #ifndef PRODUCT 3587 if(Verbose && PrintMiscellaneous) 3588 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3589 #endif 3590 } 3591 3592 os::large_page_init(); 3593 3594 // initialize suspend/resume support - must do this before signal_sets_init() 3595 if (SR_initialize() != 0) { 3596 perror("SR_initialize failed"); 3597 return JNI_ERR; 3598 } 3599 3600 Bsd::signal_sets_init(); 3601 Bsd::install_signal_handlers(); 3602 3603 // Check minimum allowable stack size for thread creation and to initialize 3604 // the java system classes, including StackOverflowError - depends on page 3605 // size. Add a page for compiler2 recursion in main thread. 3606 // Add in 2*BytesPerWord times page size to account for VM stack during 3607 // class initialization depending on 32 or 64 bit VM. 3608 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3609 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3610 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3611 3612 size_t threadStackSizeInBytes = ThreadStackSize * K; 3613 if (threadStackSizeInBytes != 0 && 3614 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3615 tty->print_cr("\nThe stack size specified is too small, " 3616 "Specify at least %dk", 3617 os::Bsd::min_stack_allowed/ K); 3618 return JNI_ERR; 3619 } 3620 3621 // Make the stack size a multiple of the page size so that 3622 // the yellow/red zones can be guarded. 3623 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3624 vm_page_size())); 3625 3626 if (MaxFDLimit) { 3627 // set the number of file descriptors to max. print out error 3628 // if getrlimit/setrlimit fails but continue regardless. 3629 struct rlimit nbr_files; 3630 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3631 if (status != 0) { 3632 if (PrintMiscellaneous && (Verbose || WizardMode)) 3633 perror("os::init_2 getrlimit failed"); 3634 } else { 3635 nbr_files.rlim_cur = nbr_files.rlim_max; 3636 3637 #ifdef __APPLE__ 3638 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3639 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3640 // be used instead 3641 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3642 #endif 3643 3644 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3645 if (status != 0) { 3646 if (PrintMiscellaneous && (Verbose || WizardMode)) 3647 perror("os::init_2 setrlimit failed"); 3648 } 3649 } 3650 } 3651 3652 // at-exit methods are called in the reverse order of their registration. 3653 // atexit functions are called on return from main or as a result of a 3654 // call to exit(3C). There can be only 32 of these functions registered 3655 // and atexit() does not set errno. 3656 3657 if (PerfAllowAtExitRegistration) { 3658 // only register atexit functions if PerfAllowAtExitRegistration is set. 3659 // atexit functions can be delayed until process exit time, which 3660 // can be problematic for embedded VM situations. Embedded VMs should 3661 // call DestroyJavaVM() to assure that VM resources are released. 3662 3663 // note: perfMemory_exit_helper atexit function may be removed in 3664 // the future if the appropriate cleanup code can be added to the 3665 // VM_Exit VMOperation's doit method. 3666 if (atexit(perfMemory_exit_helper) != 0) { 3667 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3668 } 3669 } 3670 3671 // initialize thread priority policy 3672 prio_init(); 3673 3674 #ifdef __APPLE__ 3675 // dynamically link to objective c gc registration 3676 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3677 if (handleLibObjc != NULL) { 3678 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3679 } 3680 #endif 3681 3682 return JNI_OK; 3683 } 3684 3685 // this is called at the end of vm_initialization 3686 void os::init_3(void) { } 3687 3688 // Mark the polling page as unreadable 3689 void os::make_polling_page_unreadable(void) { 3690 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 3691 fatal("Could not disable polling page"); 3692 }; 3693 3694 // Mark the polling page as readable 3695 void os::make_polling_page_readable(void) { 3696 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3697 fatal("Could not enable polling page"); 3698 } 3699 }; 3700 3701 int os::active_processor_count() { 3702 return _processor_count; 3703 } 3704 3705 void os::set_native_thread_name(const char *name) { 3706 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3707 // This is only supported in Snow Leopard and beyond 3708 if (name != NULL) { 3709 // Add a "Java: " prefix to the name 3710 char buf[MAXTHREADNAMESIZE]; 3711 snprintf(buf, sizeof(buf), "Java: %s", name); 3712 pthread_setname_np(buf); 3713 } 3714 #endif 3715 } 3716 3717 bool os::distribute_processes(uint length, uint* distribution) { 3718 // Not yet implemented. 3719 return false; 3720 } 3721 3722 bool os::bind_to_processor(uint processor_id) { 3723 // Not yet implemented. 3724 return false; 3725 } 3726 3727 void os::SuspendedThreadTask::internal_do_task() { 3728 if (do_suspend(_thread->osthread())) { 3729 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3730 do_task(context); 3731 do_resume(_thread->osthread()); 3732 } 3733 } 3734 3735 /// 3736 class PcFetcher : public os::SuspendedThreadTask { 3737 public: 3738 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3739 ExtendedPC result(); 3740 protected: 3741 void do_task(const os::SuspendedThreadTaskContext& context); 3742 private: 3743 ExtendedPC _epc; 3744 }; 3745 3746 ExtendedPC PcFetcher::result() { 3747 guarantee(is_done(), "task is not done yet."); 3748 return _epc; 3749 } 3750 3751 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3752 Thread* thread = context.thread(); 3753 OSThread* osthread = thread->osthread(); 3754 if (osthread->ucontext() != NULL) { 3755 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3756 } else { 3757 // NULL context is unexpected, double-check this is the VMThread 3758 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3759 } 3760 } 3761 3762 // Suspends the target using the signal mechanism and then grabs the PC before 3763 // resuming the target. Used by the flat-profiler only 3764 ExtendedPC os::get_thread_pc(Thread* thread) { 3765 // Make sure that it is called by the watcher for the VMThread 3766 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3767 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3768 3769 PcFetcher fetcher(thread); 3770 fetcher.run(); 3771 return fetcher.result(); 3772 } 3773 3774 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3775 { 3776 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3777 } 3778 3779 //////////////////////////////////////////////////////////////////////////////// 3780 // debug support 3781 3782 bool os::find(address addr, outputStream* st) { 3783 Dl_info dlinfo; 3784 memset(&dlinfo, 0, sizeof(dlinfo)); 3785 if (dladdr(addr, &dlinfo) != 0) { 3786 st->print(PTR_FORMAT ": ", addr); 3787 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3788 st->print("%s+%#x", dlinfo.dli_sname, 3789 addr - (intptr_t)dlinfo.dli_saddr); 3790 } else if (dlinfo.dli_fbase != NULL) { 3791 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3792 } else { 3793 st->print("<absolute address>"); 3794 } 3795 if (dlinfo.dli_fname != NULL) { 3796 st->print(" in %s", dlinfo.dli_fname); 3797 } 3798 if (dlinfo.dli_fbase != NULL) { 3799 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3800 } 3801 st->cr(); 3802 3803 if (Verbose) { 3804 // decode some bytes around the PC 3805 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3806 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3807 address lowest = (address) dlinfo.dli_sname; 3808 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3809 if (begin < lowest) begin = lowest; 3810 Dl_info dlinfo2; 3811 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3812 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3813 end = (address) dlinfo2.dli_saddr; 3814 Disassembler::decode(begin, end, st); 3815 } 3816 return true; 3817 } 3818 return false; 3819 } 3820 3821 //////////////////////////////////////////////////////////////////////////////// 3822 // misc 3823 3824 // This does not do anything on Bsd. This is basically a hook for being 3825 // able to use structured exception handling (thread-local exception filters) 3826 // on, e.g., Win32. 3827 void 3828 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3829 JavaCallArguments* args, Thread* thread) { 3830 f(value, method, args, thread); 3831 } 3832 3833 void os::print_statistics() { 3834 } 3835 3836 int os::message_box(const char* title, const char* message) { 3837 int i; 3838 fdStream err(defaultStream::error_fd()); 3839 for (i = 0; i < 78; i++) err.print_raw("="); 3840 err.cr(); 3841 err.print_raw_cr(title); 3842 for (i = 0; i < 78; i++) err.print_raw("-"); 3843 err.cr(); 3844 err.print_raw_cr(message); 3845 for (i = 0; i < 78; i++) err.print_raw("="); 3846 err.cr(); 3847 3848 char buf[16]; 3849 // Prevent process from exiting upon "read error" without consuming all CPU 3850 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3851 3852 return buf[0] == 'y' || buf[0] == 'Y'; 3853 } 3854 3855 int os::stat(const char *path, struct stat *sbuf) { 3856 char pathbuf[MAX_PATH]; 3857 if (strlen(path) > MAX_PATH - 1) { 3858 errno = ENAMETOOLONG; 3859 return -1; 3860 } 3861 os::native_path(strcpy(pathbuf, path)); 3862 return ::stat(pathbuf, sbuf); 3863 } 3864 3865 bool os::check_heap(bool force) { 3866 return true; 3867 } 3868 3869 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 3870 return ::vsnprintf(buf, count, format, args); 3871 } 3872 3873 // Is a (classpath) directory empty? 3874 bool os::dir_is_empty(const char* path) { 3875 DIR *dir = NULL; 3876 struct dirent *ptr; 3877 3878 dir = opendir(path); 3879 if (dir == NULL) return true; 3880 3881 /* Scan the directory */ 3882 bool result = true; 3883 char buf[sizeof(struct dirent) + MAX_PATH]; 3884 while (result && (ptr = ::readdir(dir)) != NULL) { 3885 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3886 result = false; 3887 } 3888 } 3889 closedir(dir); 3890 return result; 3891 } 3892 3893 // This code originates from JDK's sysOpen and open64_w 3894 // from src/solaris/hpi/src/system_md.c 3895 3896 #ifndef O_DELETE 3897 #define O_DELETE 0x10000 3898 #endif 3899 3900 // Open a file. Unlink the file immediately after open returns 3901 // if the specified oflag has the O_DELETE flag set. 3902 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3903 3904 int os::open(const char *path, int oflag, int mode) { 3905 3906 if (strlen(path) > MAX_PATH - 1) { 3907 errno = ENAMETOOLONG; 3908 return -1; 3909 } 3910 int fd; 3911 int o_delete = (oflag & O_DELETE); 3912 oflag = oflag & ~O_DELETE; 3913 3914 fd = ::open(path, oflag, mode); 3915 if (fd == -1) return -1; 3916 3917 //If the open succeeded, the file might still be a directory 3918 { 3919 struct stat buf; 3920 int ret = ::fstat(fd, &buf); 3921 int st_mode = buf.st_mode; 3922 3923 if (ret != -1) { 3924 if ((st_mode & S_IFMT) == S_IFDIR) { 3925 errno = EISDIR; 3926 ::close(fd); 3927 return -1; 3928 } 3929 } else { 3930 ::close(fd); 3931 return -1; 3932 } 3933 } 3934 3935 /* 3936 * All file descriptors that are opened in the JVM and not 3937 * specifically destined for a subprocess should have the 3938 * close-on-exec flag set. If we don't set it, then careless 3rd 3939 * party native code might fork and exec without closing all 3940 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3941 * UNIXProcess.c), and this in turn might: 3942 * 3943 * - cause end-of-file to fail to be detected on some file 3944 * descriptors, resulting in mysterious hangs, or 3945 * 3946 * - might cause an fopen in the subprocess to fail on a system 3947 * suffering from bug 1085341. 3948 * 3949 * (Yes, the default setting of the close-on-exec flag is a Unix 3950 * design flaw) 3951 * 3952 * See: 3953 * 1085341: 32-bit stdio routines should support file descriptors >255 3954 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3955 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3956 */ 3957 #ifdef FD_CLOEXEC 3958 { 3959 int flags = ::fcntl(fd, F_GETFD); 3960 if (flags != -1) 3961 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3962 } 3963 #endif 3964 3965 if (o_delete != 0) { 3966 ::unlink(path); 3967 } 3968 return fd; 3969 } 3970 3971 3972 // create binary file, rewriting existing file if required 3973 int os::create_binary_file(const char* path, bool rewrite_existing) { 3974 int oflags = O_WRONLY | O_CREAT; 3975 if (!rewrite_existing) { 3976 oflags |= O_EXCL; 3977 } 3978 return ::open(path, oflags, S_IREAD | S_IWRITE); 3979 } 3980 3981 // return current position of file pointer 3982 jlong os::current_file_offset(int fd) { 3983 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3984 } 3985 3986 // move file pointer to the specified offset 3987 jlong os::seek_to_file_offset(int fd, jlong offset) { 3988 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3989 } 3990 3991 // This code originates from JDK's sysAvailable 3992 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3993 3994 int os::available(int fd, jlong *bytes) { 3995 jlong cur, end; 3996 int mode; 3997 struct stat buf; 3998 3999 if (::fstat(fd, &buf) >= 0) { 4000 mode = buf.st_mode; 4001 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 4002 /* 4003 * XXX: is the following call interruptible? If so, this might 4004 * need to go through the INTERRUPT_IO() wrapper as for other 4005 * blocking, interruptible calls in this file. 4006 */ 4007 int n; 4008 if (::ioctl(fd, FIONREAD, &n) >= 0) { 4009 *bytes = n; 4010 return 1; 4011 } 4012 } 4013 } 4014 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 4015 return 0; 4016 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 4017 return 0; 4018 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 4019 return 0; 4020 } 4021 *bytes = end - cur; 4022 return 1; 4023 } 4024 4025 int os::socket_available(int fd, jint *pbytes) { 4026 if (fd < 0) 4027 return OS_OK; 4028 4029 int ret; 4030 4031 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 4032 4033 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 4034 // is expected to return 0 on failure and 1 on success to the jdk. 4035 4036 return (ret == OS_ERR) ? 0 : 1; 4037 } 4038 4039 // Map a block of memory. 4040 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 4041 char *addr, size_t bytes, bool read_only, 4042 bool allow_exec) { 4043 int prot; 4044 int flags; 4045 4046 if (read_only) { 4047 prot = PROT_READ; 4048 flags = MAP_SHARED; 4049 } else { 4050 prot = PROT_READ | PROT_WRITE; 4051 flags = MAP_PRIVATE; 4052 } 4053 4054 if (allow_exec) { 4055 prot |= PROT_EXEC; 4056 } 4057 4058 if (addr != NULL) { 4059 flags |= MAP_FIXED; 4060 } 4061 4062 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4063 fd, file_offset); 4064 if (mapped_address == MAP_FAILED) { 4065 return NULL; 4066 } 4067 return mapped_address; 4068 } 4069 4070 4071 // Remap a block of memory. 4072 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4073 char *addr, size_t bytes, bool read_only, 4074 bool allow_exec) { 4075 // same as map_memory() on this OS 4076 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4077 allow_exec); 4078 } 4079 4080 4081 // Unmap a block of memory. 4082 bool os::pd_unmap_memory(char* addr, size_t bytes) { 4083 return munmap(addr, bytes) == 0; 4084 } 4085 4086 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4087 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 4088 // of a thread. 4089 // 4090 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4091 // the fast estimate available on the platform. 4092 4093 jlong os::current_thread_cpu_time() { 4094 #ifdef __APPLE__ 4095 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4096 #else 4097 Unimplemented(); 4098 return 0; 4099 #endif 4100 } 4101 4102 jlong os::thread_cpu_time(Thread* thread) { 4103 #ifdef __APPLE__ 4104 return os::thread_cpu_time(thread, true /* user + sys */); 4105 #else 4106 Unimplemented(); 4107 return 0; 4108 #endif 4109 } 4110 4111 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4112 #ifdef __APPLE__ 4113 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4114 #else 4115 Unimplemented(); 4116 return 0; 4117 #endif 4118 } 4119 4120 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4121 #ifdef __APPLE__ 4122 struct thread_basic_info tinfo; 4123 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4124 kern_return_t kr; 4125 thread_t mach_thread; 4126 4127 mach_thread = thread->osthread()->thread_id(); 4128 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4129 if (kr != KERN_SUCCESS) 4130 return -1; 4131 4132 if (user_sys_cpu_time) { 4133 jlong nanos; 4134 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4135 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4136 return nanos; 4137 } else { 4138 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4139 } 4140 #else 4141 Unimplemented(); 4142 return 0; 4143 #endif 4144 } 4145 4146 4147 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4148 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4149 info_ptr->may_skip_backward = false; // elapsed time not wall time 4150 info_ptr->may_skip_forward = false; // elapsed time not wall time 4151 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4152 } 4153 4154 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4155 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4156 info_ptr->may_skip_backward = false; // elapsed time not wall time 4157 info_ptr->may_skip_forward = false; // elapsed time not wall time 4158 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4159 } 4160 4161 bool os::is_thread_cpu_time_supported() { 4162 #ifdef __APPLE__ 4163 return true; 4164 #else 4165 return false; 4166 #endif 4167 } 4168 4169 // System loadavg support. Returns -1 if load average cannot be obtained. 4170 // Bsd doesn't yet have a (official) notion of processor sets, 4171 // so just return the system wide load average. 4172 int os::loadavg(double loadavg[], int nelem) { 4173 return ::getloadavg(loadavg, nelem); 4174 } 4175 4176 void os::pause() { 4177 char filename[MAX_PATH]; 4178 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4179 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4180 } else { 4181 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4182 } 4183 4184 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4185 if (fd != -1) { 4186 struct stat buf; 4187 ::close(fd); 4188 while (::stat(filename, &buf) == 0) { 4189 (void)::poll(NULL, 0, 100); 4190 } 4191 } else { 4192 jio_fprintf(stderr, 4193 "Could not open pause file '%s', continuing immediately.\n", filename); 4194 } 4195 } 4196 4197 4198 // Refer to the comments in os_solaris.cpp park-unpark. 4199 // 4200 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4201 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4202 // For specifics regarding the bug see GLIBC BUGID 261237 : 4203 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4204 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4205 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4206 // is used. (The simple C test-case provided in the GLIBC bug report manifests the 4207 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4208 // and monitorenter when we're using 1-0 locking. All those operations may result in 4209 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4210 // of libpthread avoids the problem, but isn't practical. 4211 // 4212 // Possible remedies: 4213 // 4214 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4215 // This is palliative and probabilistic, however. If the thread is preempted 4216 // between the call to compute_abstime() and pthread_cond_timedwait(), more 4217 // than the minimum period may have passed, and the abstime may be stale (in the 4218 // past) resultin in a hang. Using this technique reduces the odds of a hang 4219 // but the JVM is still vulnerable, particularly on heavily loaded systems. 4220 // 4221 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4222 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4223 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4224 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4225 // thread. 4226 // 4227 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4228 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4229 // a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4230 // This also works well. In fact it avoids kernel-level scalability impediments 4231 // on certain platforms that don't handle lots of active pthread_cond_timedwait() 4232 // timers in a graceful fashion. 4233 // 4234 // 4. When the abstime value is in the past it appears that control returns 4235 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4236 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4237 // can avoid the problem by reinitializing the condvar -- by cond_destroy() 4238 // followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4239 // It may be possible to avoid reinitialization by checking the return 4240 // value from pthread_cond_timedwait(). In addition to reinitializing the 4241 // condvar we must establish the invariant that cond_signal() is only called 4242 // within critical sections protected by the adjunct mutex. This prevents 4243 // cond_signal() from "seeing" a condvar that's in the midst of being 4244 // reinitialized or that is corrupt. Sadly, this invariant obviates the 4245 // desirable signal-after-unlock optimization that avoids futile context switching. 4246 // 4247 // I'm also concerned that some versions of NTPL might allocate an auxilliary 4248 // structure when a condvar is used or initialized. cond_destroy() would 4249 // release the helper structure. Our reinitialize-after-timedwait fix 4250 // put excessive stress on malloc/free and locks protecting the c-heap. 4251 // 4252 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4253 // It may be possible to refine (4) by checking the kernel and NTPL verisons 4254 // and only enabling the work-around for vulnerable environments. 4255 4256 // utility to compute the abstime argument to timedwait: 4257 // millis is the relative timeout time 4258 // abstime will be the absolute timeout time 4259 // TODO: replace compute_abstime() with unpackTime() 4260 4261 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4262 if (millis < 0) millis = 0; 4263 struct timeval now; 4264 int status = gettimeofday(&now, NULL); 4265 assert(status == 0, "gettimeofday"); 4266 jlong seconds = millis / 1000; 4267 millis %= 1000; 4268 if (seconds > 50000000) { // see man cond_timedwait(3T) 4269 seconds = 50000000; 4270 } 4271 abstime->tv_sec = now.tv_sec + seconds; 4272 long usec = now.tv_usec + millis * 1000; 4273 if (usec >= 1000000) { 4274 abstime->tv_sec += 1; 4275 usec -= 1000000; 4276 } 4277 abstime->tv_nsec = usec * 1000; 4278 return abstime; 4279 } 4280 4281 4282 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 4283 // Conceptually TryPark() should be equivalent to park(0). 4284 4285 int os::PlatformEvent::TryPark() { 4286 for (;;) { 4287 const int v = _Event ; 4288 guarantee ((v == 0) || (v == 1), "invariant") ; 4289 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 4290 } 4291 } 4292 4293 void os::PlatformEvent::park() { // AKA "down()" 4294 // Invariant: Only the thread associated with the Event/PlatformEvent 4295 // may call park(). 4296 // TODO: assert that _Assoc != NULL or _Assoc == Self 4297 int v ; 4298 for (;;) { 4299 v = _Event ; 4300 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4301 } 4302 guarantee (v >= 0, "invariant") ; 4303 if (v == 0) { 4304 // Do this the hard way by blocking ... 4305 int status = pthread_mutex_lock(_mutex); 4306 assert_status(status == 0, status, "mutex_lock"); 4307 guarantee (_nParked == 0, "invariant") ; 4308 ++ _nParked ; 4309 while (_Event < 0) { 4310 status = pthread_cond_wait(_cond, _mutex); 4311 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4312 // Treat this the same as if the wait was interrupted 4313 if (status == ETIMEDOUT) { status = EINTR; } 4314 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4315 } 4316 -- _nParked ; 4317 4318 _Event = 0 ; 4319 status = pthread_mutex_unlock(_mutex); 4320 assert_status(status == 0, status, "mutex_unlock"); 4321 // Paranoia to ensure our locked and lock-free paths interact 4322 // correctly with each other. 4323 OrderAccess::fence(); 4324 } 4325 guarantee (_Event >= 0, "invariant") ; 4326 } 4327 4328 int os::PlatformEvent::park(jlong millis) { 4329 guarantee (_nParked == 0, "invariant") ; 4330 4331 int v ; 4332 for (;;) { 4333 v = _Event ; 4334 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4335 } 4336 guarantee (v >= 0, "invariant") ; 4337 if (v != 0) return OS_OK ; 4338 4339 // We do this the hard way, by blocking the thread. 4340 // Consider enforcing a minimum timeout value. 4341 struct timespec abst; 4342 compute_abstime(&abst, millis); 4343 4344 int ret = OS_TIMEOUT; 4345 int status = pthread_mutex_lock(_mutex); 4346 assert_status(status == 0, status, "mutex_lock"); 4347 guarantee (_nParked == 0, "invariant") ; 4348 ++_nParked ; 4349 4350 // Object.wait(timo) will return because of 4351 // (a) notification 4352 // (b) timeout 4353 // (c) thread.interrupt 4354 // 4355 // Thread.interrupt and object.notify{All} both call Event::set. 4356 // That is, we treat thread.interrupt as a special case of notification. 4357 // The underlying Solaris implementation, cond_timedwait, admits 4358 // spurious/premature wakeups, but the JLS/JVM spec prevents the 4359 // JVM from making those visible to Java code. As such, we must 4360 // filter out spurious wakeups. We assume all ETIME returns are valid. 4361 // 4362 // TODO: properly differentiate simultaneous notify+interrupt. 4363 // In that case, we should propagate the notify to another waiter. 4364 4365 while (_Event < 0) { 4366 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4367 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4368 pthread_cond_destroy (_cond); 4369 pthread_cond_init (_cond, NULL) ; 4370 } 4371 assert_status(status == 0 || status == EINTR || 4372 status == ETIMEDOUT, 4373 status, "cond_timedwait"); 4374 if (!FilterSpuriousWakeups) break ; // previous semantics 4375 if (status == ETIMEDOUT) break ; 4376 // We consume and ignore EINTR and spurious wakeups. 4377 } 4378 --_nParked ; 4379 if (_Event >= 0) { 4380 ret = OS_OK; 4381 } 4382 _Event = 0 ; 4383 status = pthread_mutex_unlock(_mutex); 4384 assert_status(status == 0, status, "mutex_unlock"); 4385 assert (_nParked == 0, "invariant") ; 4386 // Paranoia to ensure our locked and lock-free paths interact 4387 // correctly with each other. 4388 OrderAccess::fence(); 4389 return ret; 4390 } 4391 4392 void os::PlatformEvent::unpark() { 4393 // Transitions for _Event: 4394 // 0 :=> 1 4395 // 1 :=> 1 4396 // -1 :=> either 0 or 1; must signal target thread 4397 // That is, we can safely transition _Event from -1 to either 4398 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back 4399 // unpark() calls. 4400 // See also: "Semaphores in Plan 9" by Mullender & Cox 4401 // 4402 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4403 // that it will take two back-to-back park() calls for the owning 4404 // thread to block. This has the benefit of forcing a spurious return 4405 // from the first park() call after an unpark() call which will help 4406 // shake out uses of park() and unpark() without condition variables. 4407 4408 if (Atomic::xchg(1, &_Event) >= 0) return; 4409 4410 // Wait for the thread associated with the event to vacate 4411 int status = pthread_mutex_lock(_mutex); 4412 assert_status(status == 0, status, "mutex_lock"); 4413 int AnyWaiters = _nParked; 4414 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4415 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4416 AnyWaiters = 0; 4417 pthread_cond_signal(_cond); 4418 } 4419 status = pthread_mutex_unlock(_mutex); 4420 assert_status(status == 0, status, "mutex_unlock"); 4421 if (AnyWaiters != 0) { 4422 status = pthread_cond_signal(_cond); 4423 assert_status(status == 0, status, "cond_signal"); 4424 } 4425 4426 // Note that we signal() _after dropping the lock for "immortal" Events. 4427 // This is safe and avoids a common class of futile wakeups. In rare 4428 // circumstances this can cause a thread to return prematurely from 4429 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4430 // simply re-test the condition and re-park itself. 4431 } 4432 4433 4434 // JSR166 4435 // ------------------------------------------------------- 4436 4437 /* 4438 * The solaris and bsd implementations of park/unpark are fairly 4439 * conservative for now, but can be improved. They currently use a 4440 * mutex/condvar pair, plus a a count. 4441 * Park decrements count if > 0, else does a condvar wait. Unpark 4442 * sets count to 1 and signals condvar. Only one thread ever waits 4443 * on the condvar. Contention seen when trying to park implies that someone 4444 * is unparking you, so don't wait. And spurious returns are fine, so there 4445 * is no need to track notifications. 4446 */ 4447 4448 #define MAX_SECS 100000000 4449 /* 4450 * This code is common to bsd and solaris and will be moved to a 4451 * common place in dolphin. 4452 * 4453 * The passed in time value is either a relative time in nanoseconds 4454 * or an absolute time in milliseconds. Either way it has to be unpacked 4455 * into suitable seconds and nanoseconds components and stored in the 4456 * given timespec structure. 4457 * Given time is a 64-bit value and the time_t used in the timespec is only 4458 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4459 * overflow if times way in the future are given. Further on Solaris versions 4460 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4461 * number of seconds, in abstime, is less than current_time + 100,000,000. 4462 * As it will be 28 years before "now + 100000000" will overflow we can 4463 * ignore overflow and just impose a hard-limit on seconds using the value 4464 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4465 * years from "now". 4466 */ 4467 4468 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4469 assert (time > 0, "convertTime"); 4470 4471 struct timeval now; 4472 int status = gettimeofday(&now, NULL); 4473 assert(status == 0, "gettimeofday"); 4474 4475 time_t max_secs = now.tv_sec + MAX_SECS; 4476 4477 if (isAbsolute) { 4478 jlong secs = time / 1000; 4479 if (secs > max_secs) { 4480 absTime->tv_sec = max_secs; 4481 } 4482 else { 4483 absTime->tv_sec = secs; 4484 } 4485 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4486 } 4487 else { 4488 jlong secs = time / NANOSECS_PER_SEC; 4489 if (secs >= MAX_SECS) { 4490 absTime->tv_sec = max_secs; 4491 absTime->tv_nsec = 0; 4492 } 4493 else { 4494 absTime->tv_sec = now.tv_sec + secs; 4495 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4496 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4497 absTime->tv_nsec -= NANOSECS_PER_SEC; 4498 ++absTime->tv_sec; // note: this must be <= max_secs 4499 } 4500 } 4501 } 4502 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4503 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4504 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4505 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4506 } 4507 4508 void Parker::park(bool isAbsolute, jlong time) { 4509 // Ideally we'd do something useful while spinning, such 4510 // as calling unpackTime(). 4511 4512 // Optional fast-path check: 4513 // Return immediately if a permit is available. 4514 // We depend on Atomic::xchg() having full barrier semantics 4515 // since we are doing a lock-free update to _counter. 4516 if (Atomic::xchg(0, &_counter) > 0) return; 4517 4518 Thread* thread = Thread::current(); 4519 assert(thread->is_Java_thread(), "Must be JavaThread"); 4520 JavaThread *jt = (JavaThread *)thread; 4521 4522 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4523 // Check interrupt before trying to wait 4524 if (Thread::is_interrupted(thread, false)) { 4525 return; 4526 } 4527 4528 // Next, demultiplex/decode time arguments 4529 struct timespec absTime; 4530 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 4531 return; 4532 } 4533 if (time > 0) { 4534 unpackTime(&absTime, isAbsolute, time); 4535 } 4536 4537 4538 // Enter safepoint region 4539 // Beware of deadlocks such as 6317397. 4540 // The per-thread Parker:: mutex is a classic leaf-lock. 4541 // In particular a thread must never block on the Threads_lock while 4542 // holding the Parker:: mutex. If safepoints are pending both the 4543 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4544 ThreadBlockInVM tbivm(jt); 4545 4546 // Don't wait if cannot get lock since interference arises from 4547 // unblocking. Also. check interrupt before trying wait 4548 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4549 return; 4550 } 4551 4552 int status ; 4553 if (_counter > 0) { // no wait needed 4554 _counter = 0; 4555 status = pthread_mutex_unlock(_mutex); 4556 assert (status == 0, "invariant") ; 4557 // Paranoia to ensure our locked and lock-free paths interact 4558 // correctly with each other and Java-level accesses. 4559 OrderAccess::fence(); 4560 return; 4561 } 4562 4563 #ifdef ASSERT 4564 // Don't catch signals while blocked; let the running threads have the signals. 4565 // (This allows a debugger to break into the running thread.) 4566 sigset_t oldsigs; 4567 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4568 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4569 #endif 4570 4571 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4572 jt->set_suspend_equivalent(); 4573 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4574 4575 if (time == 0) { 4576 status = pthread_cond_wait (_cond, _mutex) ; 4577 } else { 4578 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 4579 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4580 pthread_cond_destroy (_cond) ; 4581 pthread_cond_init (_cond, NULL); 4582 } 4583 } 4584 assert_status(status == 0 || status == EINTR || 4585 status == ETIMEDOUT, 4586 status, "cond_timedwait"); 4587 4588 #ifdef ASSERT 4589 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4590 #endif 4591 4592 _counter = 0 ; 4593 status = pthread_mutex_unlock(_mutex) ; 4594 assert_status(status == 0, status, "invariant") ; 4595 // Paranoia to ensure our locked and lock-free paths interact 4596 // correctly with each other and Java-level accesses. 4597 OrderAccess::fence(); 4598 4599 // If externally suspended while waiting, re-suspend 4600 if (jt->handle_special_suspend_equivalent_condition()) { 4601 jt->java_suspend_self(); 4602 } 4603 } 4604 4605 void Parker::unpark() { 4606 int s, status ; 4607 status = pthread_mutex_lock(_mutex); 4608 assert (status == 0, "invariant") ; 4609 s = _counter; 4610 _counter = 1; 4611 if (s < 1) { 4612 if (WorkAroundNPTLTimedWaitHang) { 4613 status = pthread_cond_signal (_cond) ; 4614 assert (status == 0, "invariant") ; 4615 status = pthread_mutex_unlock(_mutex); 4616 assert (status == 0, "invariant") ; 4617 } else { 4618 status = pthread_mutex_unlock(_mutex); 4619 assert (status == 0, "invariant") ; 4620 status = pthread_cond_signal (_cond) ; 4621 assert (status == 0, "invariant") ; 4622 } 4623 } else { 4624 pthread_mutex_unlock(_mutex); 4625 assert (status == 0, "invariant") ; 4626 } 4627 } 4628 4629 4630 /* Darwin has no "environ" in a dynamic library. */ 4631 #ifdef __APPLE__ 4632 #include <crt_externs.h> 4633 #define environ (*_NSGetEnviron()) 4634 #else 4635 extern char** environ; 4636 #endif 4637 4638 // Run the specified command in a separate process. Return its exit value, 4639 // or -1 on failure (e.g. can't fork a new process). 4640 // Unlike system(), this function can be called from signal handler. It 4641 // doesn't block SIGINT et al. 4642 int os::fork_and_exec(char* cmd) { 4643 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4644 4645 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4646 // pthread_atfork handlers and reset pthread library. All we need is a 4647 // separate process to execve. Make a direct syscall to fork process. 4648 // On IA64 there's no fork syscall, we have to use fork() and hope for 4649 // the best... 4650 pid_t pid = fork(); 4651 4652 if (pid < 0) { 4653 // fork failed 4654 return -1; 4655 4656 } else if (pid == 0) { 4657 // child process 4658 4659 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4660 // first to kill every thread on the thread list. Because this list is 4661 // not reset by fork() (see notes above), execve() will instead kill 4662 // every thread in the parent process. We know this is the only thread 4663 // in the new process, so make a system call directly. 4664 // IA64 should use normal execve() from glibc to match the glibc fork() 4665 // above. 4666 execve("/bin/sh", (char* const*)argv, environ); 4667 4668 // execve failed 4669 _exit(-1); 4670 4671 } else { 4672 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4673 // care about the actual exit code, for now. 4674 4675 int status; 4676 4677 // Wait for the child process to exit. This returns immediately if 4678 // the child has already exited. */ 4679 while (waitpid(pid, &status, 0) < 0) { 4680 switch (errno) { 4681 case ECHILD: return 0; 4682 case EINTR: break; 4683 default: return -1; 4684 } 4685 } 4686 4687 if (WIFEXITED(status)) { 4688 // The child exited normally; get its exit code. 4689 return WEXITSTATUS(status); 4690 } else if (WIFSIGNALED(status)) { 4691 // The child exited because of a signal 4692 // The best value to return is 0x80 + signal number, 4693 // because that is what all Unix shells do, and because 4694 // it allows callers to distinguish between process exit and 4695 // process death by signal. 4696 return 0x80 + WTERMSIG(status); 4697 } else { 4698 // Unknown exit code; pass it through 4699 return status; 4700 } 4701 } 4702 } 4703 4704 // is_headless_jre() 4705 // 4706 // Test for the existence of xawt/libmawt.so or libawt_xawt.so 4707 // in order to report if we are running in a headless jre 4708 // 4709 // Since JDK8 xawt/libmawt.so was moved into the same directory 4710 // as libawt.so, and renamed libawt_xawt.so 4711 // 4712 bool os::is_headless_jre() { 4713 struct stat statbuf; 4714 char buf[MAXPATHLEN]; 4715 char libmawtpath[MAXPATHLEN]; 4716 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4717 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4718 char *p; 4719 4720 // Get path to libjvm.so 4721 os::jvm_path(buf, sizeof(buf)); 4722 4723 // Get rid of libjvm.so 4724 p = strrchr(buf, '/'); 4725 if (p == NULL) return false; 4726 else *p = '\0'; 4727 4728 // Get rid of client or server 4729 p = strrchr(buf, '/'); 4730 if (p == NULL) return false; 4731 else *p = '\0'; 4732 4733 // check xawt/libmawt.so 4734 strcpy(libmawtpath, buf); 4735 strcat(libmawtpath, xawtstr); 4736 if (::stat(libmawtpath, &statbuf) == 0) return false; 4737 4738 // check libawt_xawt.so 4739 strcpy(libmawtpath, buf); 4740 strcat(libmawtpath, new_xawtstr); 4741 if (::stat(libmawtpath, &statbuf) == 0) return false; 4742 4743 return true; 4744 } 4745 4746 // Get the default path to the core file 4747 // Returns the length of the string 4748 int os::get_core_path(char* buffer, size_t bufferSize) { 4749 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4750 4751 // Truncate if theoretical string was longer than bufferSize 4752 n = MIN2(n, (int)bufferSize); 4753 4754 return n; 4755 } 4756 4757 #ifndef PRODUCT 4758 void TestReserveMemorySpecial_test() { 4759 // No tests available for this platform 4760 } 4761 #endif