1 /* 2 * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "jvm.h" 27 #include "classfile/classLoader.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/icBuffer.hpp" 31 #include "code/vtableStubs.hpp" 32 #include "compiler/compileBroker.hpp" 33 #include "compiler/disassembler.hpp" 34 #include "interpreter/interpreter.hpp" 35 #include "logging/log.hpp" 36 #include "memory/allocation.inline.hpp" 37 #include "memory/filemap.hpp" 38 #include "oops/oop.inline.hpp" 39 #include "os_bsd.inline.hpp" 40 #include "os_share_bsd.hpp" 41 #include "prims/jniFastGetField.hpp" 42 #include "prims/jvm_misc.hpp" 43 #include "runtime/arguments.hpp" 44 #include "runtime/atomic.hpp" 45 #include "runtime/extendedPC.hpp" 46 #include "runtime/globals.hpp" 47 #include "runtime/interfaceSupport.inline.hpp" 48 #include "runtime/java.hpp" 49 #include "runtime/javaCalls.hpp" 50 #include "runtime/mutexLocker.hpp" 51 #include "runtime/objectMonitor.hpp" 52 #include "runtime/orderAccess.hpp" 53 #include "runtime/osThread.hpp" 54 #include "runtime/perfMemory.hpp" 55 #include "runtime/semaphore.hpp" 56 #include "runtime/sharedRuntime.hpp" 57 #include "runtime/statSampler.hpp" 58 #include "runtime/stubRoutines.hpp" 59 #include "runtime/thread.inline.hpp" 60 #include "runtime/threadCritical.hpp" 61 #include "runtime/timer.hpp" 62 #include "services/attachListener.hpp" 63 #include "services/memTracker.hpp" 64 #include "services/runtimeService.hpp" 65 #include "utilities/align.hpp" 66 #include "utilities/decoder.hpp" 67 #include "utilities/defaultStream.hpp" 68 #include "utilities/events.hpp" 69 #include "utilities/growableArray.hpp" 70 #include "utilities/vmError.hpp" 71 72 // put OS-includes here 73 # include <dlfcn.h> 74 # include <errno.h> 75 # include <fcntl.h> 76 # include <inttypes.h> 77 # include <poll.h> 78 # include <pthread.h> 79 # include <pwd.h> 80 # include <signal.h> 81 # include <stdint.h> 82 # include <stdio.h> 83 # include <string.h> 84 # include <sys/ioctl.h> 85 # include <sys/mman.h> 86 # include <sys/param.h> 87 # include <sys/resource.h> 88 # include <sys/socket.h> 89 # include <sys/stat.h> 90 # include <sys/syscall.h> 91 # include <sys/sysctl.h> 92 # include <sys/time.h> 93 # include <sys/times.h> 94 # include <sys/types.h> 95 # include <sys/wait.h> 96 # include <time.h> 97 # include <unistd.h> 98 99 #if defined(__FreeBSD__) || defined(__NetBSD__) 100 #include <elf.h> 101 #endif 102 103 #ifdef __APPLE__ 104 #include <mach-o/dyld.h> 105 #endif 106 107 #ifndef MAP_ANONYMOUS 108 #define MAP_ANONYMOUS MAP_ANON 109 #endif 110 111 #define MAX_PATH (2 * K) 112 113 // for timer info max values which include all bits 114 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 115 116 //////////////////////////////////////////////////////////////////////////////// 117 // global variables 118 julong os::Bsd::_physical_memory = 0; 119 120 #ifdef __APPLE__ 121 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 122 volatile uint64_t os::Bsd::_max_abstime = 0; 123 #else 124 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 125 #endif 126 pthread_t os::Bsd::_main_thread; 127 int os::Bsd::_page_size = -1; 128 129 static jlong initial_time_count=0; 130 131 static int clock_tics_per_sec = 100; 132 133 // For diagnostics to print a message once. see run_periodic_checks 134 static sigset_t check_signal_done; 135 static bool check_signals = true; 136 137 static pid_t _initial_pid = 0; 138 139 // Signal number used to suspend/resume a thread 140 141 // do not use any signal number less than SIGSEGV, see 4355769 142 static int SR_signum = SIGUSR2; 143 sigset_t SR_sigset; 144 145 146 //////////////////////////////////////////////////////////////////////////////// 147 // utility functions 148 149 static int SR_initialize(); 150 151 julong os::available_memory() { 152 return Bsd::available_memory(); 153 } 154 155 // available here means free 156 julong os::Bsd::available_memory() { 157 uint64_t available = physical_memory() >> 2; 158 #ifdef __APPLE__ 159 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 160 vm_statistics64_data_t vmstat; 161 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 162 (host_info64_t)&vmstat, &count); 163 assert(kerr == KERN_SUCCESS, 164 "host_statistics64 failed - check mach_host_self() and count"); 165 if (kerr == KERN_SUCCESS) { 166 available = vmstat.free_count * os::vm_page_size(); 167 } 168 #endif 169 return available; 170 } 171 172 julong os::physical_memory() { 173 return Bsd::physical_memory(); 174 } 175 176 // Return true if user is running as root. 177 178 bool os::have_special_privileges() { 179 static bool init = false; 180 static bool privileges = false; 181 if (!init) { 182 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 183 init = true; 184 } 185 return privileges; 186 } 187 188 189 190 // Cpu architecture string 191 #if defined(ZERO) 192 static char cpu_arch[] = ZERO_LIBARCH; 193 #elif defined(IA64) 194 static char cpu_arch[] = "ia64"; 195 #elif defined(IA32) 196 static char cpu_arch[] = "i386"; 197 #elif defined(AMD64) 198 static char cpu_arch[] = "amd64"; 199 #elif defined(ARM) 200 static char cpu_arch[] = "arm"; 201 #elif defined(PPC32) 202 static char cpu_arch[] = "ppc"; 203 #elif defined(SPARC) 204 #ifdef _LP64 205 static char cpu_arch[] = "sparcv9"; 206 #else 207 static char cpu_arch[] = "sparc"; 208 #endif 209 #else 210 #error Add appropriate cpu_arch setting 211 #endif 212 213 // Compiler variant 214 #ifdef COMPILER2 215 #define COMPILER_VARIANT "server" 216 #else 217 #define COMPILER_VARIANT "client" 218 #endif 219 220 221 void os::Bsd::initialize_system_info() { 222 int mib[2]; 223 size_t len; 224 int cpu_val; 225 julong mem_val; 226 227 // get processors count via hw.ncpus sysctl 228 mib[0] = CTL_HW; 229 mib[1] = HW_NCPU; 230 len = sizeof(cpu_val); 231 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 232 assert(len == sizeof(cpu_val), "unexpected data size"); 233 set_processor_count(cpu_val); 234 } else { 235 set_processor_count(1); // fallback 236 } 237 238 // get physical memory via hw.memsize sysctl (hw.memsize is used 239 // since it returns a 64 bit value) 240 mib[0] = CTL_HW; 241 242 #if defined (HW_MEMSIZE) // Apple 243 mib[1] = HW_MEMSIZE; 244 #elif defined(HW_PHYSMEM) // Most of BSD 245 mib[1] = HW_PHYSMEM; 246 #elif defined(HW_REALMEM) // Old FreeBSD 247 mib[1] = HW_REALMEM; 248 #else 249 #error No ways to get physmem 250 #endif 251 252 len = sizeof(mem_val); 253 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 254 assert(len == sizeof(mem_val), "unexpected data size"); 255 _physical_memory = mem_val; 256 } else { 257 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 258 } 259 260 #ifdef __OpenBSD__ 261 { 262 // limit _physical_memory memory view on OpenBSD since 263 // datasize rlimit restricts us anyway. 264 struct rlimit limits; 265 getrlimit(RLIMIT_DATA, &limits); 266 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 267 } 268 #endif 269 } 270 271 #ifdef __APPLE__ 272 static const char *get_home() { 273 const char *home_dir = ::getenv("HOME"); 274 if ((home_dir == NULL) || (*home_dir == '\0')) { 275 struct passwd *passwd_info = getpwuid(geteuid()); 276 if (passwd_info != NULL) { 277 home_dir = passwd_info->pw_dir; 278 } 279 } 280 281 return home_dir; 282 } 283 #endif 284 285 void os::init_system_properties_values() { 286 // The next steps are taken in the product version: 287 // 288 // Obtain the JAVA_HOME value from the location of libjvm.so. 289 // This library should be located at: 290 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 291 // 292 // If "/jre/lib/" appears at the right place in the path, then we 293 // assume libjvm.so is installed in a JDK and we use this path. 294 // 295 // Otherwise exit with message: "Could not create the Java virtual machine." 296 // 297 // The following extra steps are taken in the debugging version: 298 // 299 // If "/jre/lib/" does NOT appear at the right place in the path 300 // instead of exit check for $JAVA_HOME environment variable. 301 // 302 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 303 // then we append a fake suffix "hotspot/libjvm.so" to this path so 304 // it looks like libjvm.so is installed there 305 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 306 // 307 // Otherwise exit. 308 // 309 // Important note: if the location of libjvm.so changes this 310 // code needs to be changed accordingly. 311 312 // See ld(1): 313 // The linker uses the following search paths to locate required 314 // shared libraries: 315 // 1: ... 316 // ... 317 // 7: The default directories, normally /lib and /usr/lib. 318 #ifndef DEFAULT_LIBPATH 319 #define DEFAULT_LIBPATH "/lib:/usr/lib" 320 #endif 321 322 // Base path of extensions installed on the system. 323 #define SYS_EXT_DIR "/usr/java/packages" 324 #define EXTENSIONS_DIR "/lib/ext" 325 326 #ifndef __APPLE__ 327 328 // Buffer that fits several sprintfs. 329 // Note that the space for the colon and the trailing null are provided 330 // by the nulls included by the sizeof operator. 331 const size_t bufsize = 332 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 333 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 334 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 335 336 // sysclasspath, java_home, dll_dir 337 { 338 char *pslash; 339 os::jvm_path(buf, bufsize); 340 341 // Found the full path to libjvm.so. 342 // Now cut the path to <java_home>/jre if we can. 343 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 344 pslash = strrchr(buf, '/'); 345 if (pslash != NULL) { 346 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 347 } 348 Arguments::set_dll_dir(buf); 349 350 if (pslash != NULL) { 351 pslash = strrchr(buf, '/'); 352 if (pslash != NULL) { 353 *pslash = '\0'; // Get rid of /<arch>. 354 pslash = strrchr(buf, '/'); 355 if (pslash != NULL) { 356 *pslash = '\0'; // Get rid of /lib. 357 } 358 } 359 } 360 Arguments::set_java_home(buf); 361 if (!set_boot_path('/', ':')) { 362 vm_exit_during_initialization("Failed setting boot class path.", NULL); 363 } 364 } 365 366 // Where to look for native libraries. 367 // 368 // Note: Due to a legacy implementation, most of the library path 369 // is set in the launcher. This was to accomodate linking restrictions 370 // on legacy Bsd implementations (which are no longer supported). 371 // Eventually, all the library path setting will be done here. 372 // 373 // However, to prevent the proliferation of improperly built native 374 // libraries, the new path component /usr/java/packages is added here. 375 // Eventually, all the library path setting will be done here. 376 { 377 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 378 // should always exist (until the legacy problem cited above is 379 // addressed). 380 const char *v = ::getenv("LD_LIBRARY_PATH"); 381 const char *v_colon = ":"; 382 if (v == NULL) { v = ""; v_colon = ""; } 383 // That's +1 for the colon and +1 for the trailing '\0'. 384 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 385 strlen(v) + 1 + 386 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 387 mtInternal); 388 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 389 Arguments::set_library_path(ld_library_path); 390 FREE_C_HEAP_ARRAY(char, ld_library_path); 391 } 392 393 // Extensions directories. 394 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 395 Arguments::set_ext_dirs(buf); 396 397 FREE_C_HEAP_ARRAY(char, buf); 398 399 #else // __APPLE__ 400 401 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 402 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 403 404 const char *user_home_dir = get_home(); 405 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 406 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 407 sizeof(SYS_EXTENSIONS_DIRS); 408 409 // Buffer that fits several sprintfs. 410 // Note that the space for the colon and the trailing null are provided 411 // by the nulls included by the sizeof operator. 412 const size_t bufsize = 413 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 414 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 415 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 416 417 // sysclasspath, java_home, dll_dir 418 { 419 char *pslash; 420 os::jvm_path(buf, bufsize); 421 422 // Found the full path to libjvm.so. 423 // Now cut the path to <java_home>/jre if we can. 424 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 425 pslash = strrchr(buf, '/'); 426 if (pslash != NULL) { 427 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 428 } 429 #ifdef STATIC_BUILD 430 strcat(buf, "/lib"); 431 #endif 432 433 Arguments::set_dll_dir(buf); 434 435 if (pslash != NULL) { 436 pslash = strrchr(buf, '/'); 437 if (pslash != NULL) { 438 *pslash = '\0'; // Get rid of /lib. 439 } 440 } 441 Arguments::set_java_home(buf); 442 set_boot_path('/', ':'); 443 } 444 445 // Where to look for native libraries. 446 // 447 // Note: Due to a legacy implementation, most of the library path 448 // is set in the launcher. This was to accomodate linking restrictions 449 // on legacy Bsd implementations (which are no longer supported). 450 // Eventually, all the library path setting will be done here. 451 // 452 // However, to prevent the proliferation of improperly built native 453 // libraries, the new path component /usr/java/packages is added here. 454 // Eventually, all the library path setting will be done here. 455 { 456 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 457 // should always exist (until the legacy problem cited above is 458 // addressed). 459 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 460 // can specify a directory inside an app wrapper 461 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 462 const char *l_colon = ":"; 463 if (l == NULL) { l = ""; l_colon = ""; } 464 465 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 466 const char *v_colon = ":"; 467 if (v == NULL) { v = ""; v_colon = ""; } 468 469 // Apple's Java6 has "." at the beginning of java.library.path. 470 // OpenJDK on Windows has "." at the end of java.library.path. 471 // OpenJDK on Linux and Solaris don't have "." in java.library.path 472 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 473 // "." is appended to the end of java.library.path. Yes, this 474 // could cause a change in behavior, but Apple's Java6 behavior 475 // can be achieved by putting "." at the beginning of the 476 // JAVA_LIBRARY_PATH environment variable. 477 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 478 strlen(v) + 1 + strlen(l) + 1 + 479 system_ext_size + 3, 480 mtInternal); 481 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 482 v, v_colon, l, l_colon, user_home_dir); 483 Arguments::set_library_path(ld_library_path); 484 FREE_C_HEAP_ARRAY(char, ld_library_path); 485 } 486 487 // Extensions directories. 488 // 489 // Note that the space for the colon and the trailing null are provided 490 // by the nulls included by the sizeof operator (so actually one byte more 491 // than necessary is allocated). 492 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 493 user_home_dir, Arguments::get_java_home()); 494 Arguments::set_ext_dirs(buf); 495 496 FREE_C_HEAP_ARRAY(char, buf); 497 498 #undef SYS_EXTENSIONS_DIR 499 #undef SYS_EXTENSIONS_DIRS 500 501 #endif // __APPLE__ 502 503 #undef SYS_EXT_DIR 504 #undef EXTENSIONS_DIR 505 } 506 507 //////////////////////////////////////////////////////////////////////////////// 508 // breakpoint support 509 510 void os::breakpoint() { 511 BREAKPOINT; 512 } 513 514 extern "C" void breakpoint() { 515 // use debugger to set breakpoint here 516 } 517 518 //////////////////////////////////////////////////////////////////////////////// 519 // signal support 520 521 debug_only(static bool signal_sets_initialized = false); 522 static sigset_t unblocked_sigs, vm_sigs; 523 524 void os::Bsd::signal_sets_init() { 525 // Should also have an assertion stating we are still single-threaded. 526 assert(!signal_sets_initialized, "Already initialized"); 527 // Fill in signals that are necessarily unblocked for all threads in 528 // the VM. Currently, we unblock the following signals: 529 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 530 // by -Xrs (=ReduceSignalUsage)); 531 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 532 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 533 // the dispositions or masks wrt these signals. 534 // Programs embedding the VM that want to use the above signals for their 535 // own purposes must, at this time, use the "-Xrs" option to prevent 536 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 537 // (See bug 4345157, and other related bugs). 538 // In reality, though, unblocking these signals is really a nop, since 539 // these signals are not blocked by default. 540 sigemptyset(&unblocked_sigs); 541 sigaddset(&unblocked_sigs, SIGILL); 542 sigaddset(&unblocked_sigs, SIGSEGV); 543 sigaddset(&unblocked_sigs, SIGBUS); 544 sigaddset(&unblocked_sigs, SIGFPE); 545 sigaddset(&unblocked_sigs, SR_signum); 546 547 if (!ReduceSignalUsage) { 548 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 549 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 550 551 } 552 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 553 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 554 } 555 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 556 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 557 } 558 } 559 // Fill in signals that are blocked by all but the VM thread. 560 sigemptyset(&vm_sigs); 561 if (!ReduceSignalUsage) { 562 sigaddset(&vm_sigs, BREAK_SIGNAL); 563 } 564 debug_only(signal_sets_initialized = true); 565 566 } 567 568 // These are signals that are unblocked while a thread is running Java. 569 // (For some reason, they get blocked by default.) 570 sigset_t* os::Bsd::unblocked_signals() { 571 assert(signal_sets_initialized, "Not initialized"); 572 return &unblocked_sigs; 573 } 574 575 // These are the signals that are blocked while a (non-VM) thread is 576 // running Java. Only the VM thread handles these signals. 577 sigset_t* os::Bsd::vm_signals() { 578 assert(signal_sets_initialized, "Not initialized"); 579 return &vm_sigs; 580 } 581 582 void os::Bsd::hotspot_sigmask(Thread* thread) { 583 584 //Save caller's signal mask before setting VM signal mask 585 sigset_t caller_sigmask; 586 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 587 588 OSThread* osthread = thread->osthread(); 589 osthread->set_caller_sigmask(caller_sigmask); 590 591 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 592 593 if (!ReduceSignalUsage) { 594 if (thread->is_VM_thread()) { 595 // Only the VM thread handles BREAK_SIGNAL ... 596 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 597 } else { 598 // ... all other threads block BREAK_SIGNAL 599 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 600 } 601 } 602 } 603 604 605 ////////////////////////////////////////////////////////////////////////////// 606 // create new thread 607 608 #ifdef __APPLE__ 609 // library handle for calling objc_registerThreadWithCollector() 610 // without static linking to the libobjc library 611 #define OBJC_LIB "/usr/lib/libobjc.dylib" 612 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 613 typedef void (*objc_registerThreadWithCollector_t)(); 614 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 615 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 616 #endif 617 618 #ifdef __APPLE__ 619 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 620 // Additional thread_id used to correlate threads in SA 621 thread_identifier_info_data_t m_ident_info; 622 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 623 624 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 625 (thread_info_t) &m_ident_info, &count); 626 627 return m_ident_info.thread_id; 628 } 629 #endif 630 631 // Thread start routine for all newly created threads 632 static void *thread_native_entry(Thread *thread) { 633 // Try to randomize the cache line index of hot stack frames. 634 // This helps when threads of the same stack traces evict each other's 635 // cache lines. The threads can be either from the same JVM instance, or 636 // from different JVM instances. The benefit is especially true for 637 // processors with hyperthreading technology. 638 static int counter = 0; 639 int pid = os::current_process_id(); 640 alloca(((pid ^ counter++) & 7) * 128); 641 642 thread->initialize_thread_current(); 643 644 OSThread* osthread = thread->osthread(); 645 Monitor* sync = osthread->startThread_lock(); 646 647 osthread->set_thread_id(os::Bsd::gettid()); 648 649 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 650 os::current_thread_id(), (uintx) pthread_self()); 651 652 #ifdef __APPLE__ 653 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 654 guarantee(unique_thread_id != 0, "unique thread id was not found"); 655 osthread->set_unique_thread_id(unique_thread_id); 656 #endif 657 // initialize signal mask for this thread 658 os::Bsd::hotspot_sigmask(thread); 659 660 // initialize floating point control register 661 os::Bsd::init_thread_fpu_state(); 662 663 #ifdef __APPLE__ 664 // register thread with objc gc 665 if (objc_registerThreadWithCollectorFunction != NULL) { 666 objc_registerThreadWithCollectorFunction(); 667 } 668 #endif 669 670 // handshaking with parent thread 671 { 672 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 673 674 // notify parent thread 675 osthread->set_state(INITIALIZED); 676 sync->notify_all(); 677 678 // wait until os::start_thread() 679 while (osthread->get_state() == INITIALIZED) { 680 sync->wait(Mutex::_no_safepoint_check_flag); 681 } 682 } 683 684 // call one more level start routine 685 thread->run(); 686 687 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 688 os::current_thread_id(), (uintx) pthread_self()); 689 690 // If a thread has not deleted itself ("delete this") as part of its 691 // termination sequence, we have to ensure thread-local-storage is 692 // cleared before we actually terminate. No threads should ever be 693 // deleted asynchronously with respect to their termination. 694 if (Thread::current_or_null_safe() != NULL) { 695 assert(Thread::current_or_null_safe() == thread, "current thread is wrong"); 696 thread->clear_thread_current(); 697 } 698 699 return 0; 700 } 701 702 bool os::create_thread(Thread* thread, ThreadType thr_type, 703 size_t req_stack_size) { 704 assert(thread->osthread() == NULL, "caller responsible"); 705 706 // Allocate the OSThread object 707 OSThread* osthread = new OSThread(NULL, NULL); 708 if (osthread == NULL) { 709 return false; 710 } 711 712 // set the correct thread state 713 osthread->set_thread_type(thr_type); 714 715 // Initial state is ALLOCATED but not INITIALIZED 716 osthread->set_state(ALLOCATED); 717 718 thread->set_osthread(osthread); 719 720 // init thread attributes 721 pthread_attr_t attr; 722 pthread_attr_init(&attr); 723 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 724 725 // calculate stack size if it's not specified by caller 726 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size); 727 int status = pthread_attr_setstacksize(&attr, stack_size); 728 assert_status(status == 0, status, "pthread_attr_setstacksize"); 729 730 ThreadState state; 731 732 { 733 pthread_t tid; 734 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread); 735 736 char buf[64]; 737 if (ret == 0) { 738 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ", 739 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr)); 740 } else { 741 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.", 742 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr)); 743 } 744 745 pthread_attr_destroy(&attr); 746 747 if (ret != 0) { 748 // Need to clean up stuff we've allocated so far 749 thread->set_osthread(NULL); 750 delete osthread; 751 return false; 752 } 753 754 // Store pthread info into the OSThread 755 osthread->set_pthread_id(tid); 756 757 // Wait until child thread is either initialized or aborted 758 { 759 Monitor* sync_with_child = osthread->startThread_lock(); 760 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 761 while ((state = osthread->get_state()) == ALLOCATED) { 762 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 763 } 764 } 765 766 } 767 768 // Aborted due to thread limit being reached 769 if (state == ZOMBIE) { 770 thread->set_osthread(NULL); 771 delete osthread; 772 return false; 773 } 774 775 // The thread is returned suspended (in state INITIALIZED), 776 // and is started higher up in the call chain 777 assert(state == INITIALIZED, "race condition"); 778 return true; 779 } 780 781 ///////////////////////////////////////////////////////////////////////////// 782 // attach existing thread 783 784 // bootstrap the main thread 785 bool os::create_main_thread(JavaThread* thread) { 786 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 787 return create_attached_thread(thread); 788 } 789 790 bool os::create_attached_thread(JavaThread* thread) { 791 #ifdef ASSERT 792 thread->verify_not_published(); 793 #endif 794 795 // Allocate the OSThread object 796 OSThread* osthread = new OSThread(NULL, NULL); 797 798 if (osthread == NULL) { 799 return false; 800 } 801 802 osthread->set_thread_id(os::Bsd::gettid()); 803 804 // Store pthread info into the OSThread 805 #ifdef __APPLE__ 806 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 807 guarantee(unique_thread_id != 0, "just checking"); 808 osthread->set_unique_thread_id(unique_thread_id); 809 #endif 810 osthread->set_pthread_id(::pthread_self()); 811 812 // initialize floating point control register 813 os::Bsd::init_thread_fpu_state(); 814 815 // Initial thread state is RUNNABLE 816 osthread->set_state(RUNNABLE); 817 818 thread->set_osthread(osthread); 819 820 // initialize signal mask for this thread 821 // and save the caller's signal mask 822 os::Bsd::hotspot_sigmask(thread); 823 824 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 825 os::current_thread_id(), (uintx) pthread_self()); 826 827 return true; 828 } 829 830 void os::pd_start_thread(Thread* thread) { 831 OSThread * osthread = thread->osthread(); 832 assert(osthread->get_state() != INITIALIZED, "just checking"); 833 Monitor* sync_with_child = osthread->startThread_lock(); 834 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 835 sync_with_child->notify(); 836 } 837 838 // Free Bsd resources related to the OSThread 839 void os::free_thread(OSThread* osthread) { 840 assert(osthread != NULL, "osthread not set"); 841 842 // We are told to free resources of the argument thread, 843 // but we can only really operate on the current thread. 844 assert(Thread::current()->osthread() == osthread, 845 "os::free_thread but not current thread"); 846 847 // Restore caller's signal mask 848 sigset_t sigmask = osthread->caller_sigmask(); 849 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 850 851 delete osthread; 852 } 853 854 //////////////////////////////////////////////////////////////////////////////// 855 // time support 856 857 // Time since start-up in seconds to a fine granularity. 858 // Used by VMSelfDestructTimer and the MemProfiler. 859 double os::elapsedTime() { 860 861 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 862 } 863 864 jlong os::elapsed_counter() { 865 return javaTimeNanos() - initial_time_count; 866 } 867 868 jlong os::elapsed_frequency() { 869 return NANOSECS_PER_SEC; // nanosecond resolution 870 } 871 872 bool os::supports_vtime() { return true; } 873 bool os::enable_vtime() { return false; } 874 bool os::vtime_enabled() { return false; } 875 876 double os::elapsedVTime() { 877 // better than nothing, but not much 878 return elapsedTime(); 879 } 880 881 jlong os::javaTimeMillis() { 882 timeval time; 883 int status = gettimeofday(&time, NULL); 884 assert(status != -1, "bsd error"); 885 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 886 } 887 888 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 889 timeval time; 890 int status = gettimeofday(&time, NULL); 891 assert(status != -1, "bsd error"); 892 seconds = jlong(time.tv_sec); 893 nanos = jlong(time.tv_usec) * 1000; 894 } 895 896 #ifndef __APPLE__ 897 #ifndef CLOCK_MONOTONIC 898 #define CLOCK_MONOTONIC (1) 899 #endif 900 #endif 901 902 #ifdef __APPLE__ 903 void os::Bsd::clock_init() { 904 mach_timebase_info(&_timebase_info); 905 } 906 #else 907 void os::Bsd::clock_init() { 908 struct timespec res; 909 struct timespec tp; 910 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 911 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 912 // yes, monotonic clock is supported 913 _clock_gettime = ::clock_gettime; 914 } 915 } 916 #endif 917 918 919 920 #ifdef __APPLE__ 921 922 jlong os::javaTimeNanos() { 923 const uint64_t tm = mach_absolute_time(); 924 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 925 const uint64_t prev = Bsd::_max_abstime; 926 if (now <= prev) { 927 return prev; // same or retrograde time; 928 } 929 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev); 930 assert(obsv >= prev, "invariant"); // Monotonicity 931 // If the CAS succeeded then we're done and return "now". 932 // If the CAS failed and the observed value "obsv" is >= now then 933 // we should return "obsv". If the CAS failed and now > obsv > prv then 934 // some other thread raced this thread and installed a new value, in which case 935 // we could either (a) retry the entire operation, (b) retry trying to install now 936 // or (c) just return obsv. We use (c). No loop is required although in some cases 937 // we might discard a higher "now" value in deference to a slightly lower but freshly 938 // installed obsv value. That's entirely benign -- it admits no new orderings compared 939 // to (a) or (b) -- and greatly reduces coherence traffic. 940 // We might also condition (c) on the magnitude of the delta between obsv and now. 941 // Avoiding excessive CAS operations to hot RW locations is critical. 942 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 943 return (prev == obsv) ? now : obsv; 944 } 945 946 #else // __APPLE__ 947 948 jlong os::javaTimeNanos() { 949 if (os::supports_monotonic_clock()) { 950 struct timespec tp; 951 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 952 assert(status == 0, "gettime error"); 953 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 954 return result; 955 } else { 956 timeval time; 957 int status = gettimeofday(&time, NULL); 958 assert(status != -1, "bsd error"); 959 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 960 return 1000 * usecs; 961 } 962 } 963 964 #endif // __APPLE__ 965 966 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 967 if (os::supports_monotonic_clock()) { 968 info_ptr->max_value = ALL_64_BITS; 969 970 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 971 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 972 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 973 } else { 974 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 975 info_ptr->max_value = ALL_64_BITS; 976 977 // gettimeofday is a real time clock so it skips 978 info_ptr->may_skip_backward = true; 979 info_ptr->may_skip_forward = true; 980 } 981 982 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 983 } 984 985 // Return the real, user, and system times in seconds from an 986 // arbitrary fixed point in the past. 987 bool os::getTimesSecs(double* process_real_time, 988 double* process_user_time, 989 double* process_system_time) { 990 struct tms ticks; 991 clock_t real_ticks = times(&ticks); 992 993 if (real_ticks == (clock_t) (-1)) { 994 return false; 995 } else { 996 double ticks_per_second = (double) clock_tics_per_sec; 997 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 998 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 999 *process_real_time = ((double) real_ticks) / ticks_per_second; 1000 1001 return true; 1002 } 1003 } 1004 1005 1006 char * os::local_time_string(char *buf, size_t buflen) { 1007 struct tm t; 1008 time_t long_time; 1009 time(&long_time); 1010 localtime_r(&long_time, &t); 1011 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1012 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1013 t.tm_hour, t.tm_min, t.tm_sec); 1014 return buf; 1015 } 1016 1017 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1018 return localtime_r(clock, res); 1019 } 1020 1021 //////////////////////////////////////////////////////////////////////////////// 1022 // runtime exit support 1023 1024 // Note: os::shutdown() might be called very early during initialization, or 1025 // called from signal handler. Before adding something to os::shutdown(), make 1026 // sure it is async-safe and can handle partially initialized VM. 1027 void os::shutdown() { 1028 1029 // allow PerfMemory to attempt cleanup of any persistent resources 1030 perfMemory_exit(); 1031 1032 // needs to remove object in file system 1033 AttachListener::abort(); 1034 1035 // flush buffered output, finish log files 1036 ostream_abort(); 1037 1038 // Check for abort hook 1039 abort_hook_t abort_hook = Arguments::abort_hook(); 1040 if (abort_hook != NULL) { 1041 abort_hook(); 1042 } 1043 1044 } 1045 1046 // Note: os::abort() might be called very early during initialization, or 1047 // called from signal handler. Before adding something to os::abort(), make 1048 // sure it is async-safe and can handle partially initialized VM. 1049 void os::abort(bool dump_core, void* siginfo, const void* context) { 1050 os::shutdown(); 1051 if (dump_core) { 1052 #ifndef PRODUCT 1053 fdStream out(defaultStream::output_fd()); 1054 out.print_raw("Current thread is "); 1055 char buf[16]; 1056 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1057 out.print_raw_cr(buf); 1058 out.print_raw_cr("Dumping core ..."); 1059 #endif 1060 ::abort(); // dump core 1061 } 1062 1063 ::exit(1); 1064 } 1065 1066 // Die immediately, no exit hook, no abort hook, no cleanup. 1067 void os::die() { 1068 // _exit() on BsdThreads only kills current thread 1069 ::abort(); 1070 } 1071 1072 // Information of current thread in variety of formats 1073 pid_t os::Bsd::gettid() { 1074 int retval = -1; 1075 1076 #ifdef __APPLE__ //XNU kernel 1077 // despite the fact mach port is actually not a thread id use it 1078 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1079 retval = ::pthread_mach_thread_np(::pthread_self()); 1080 guarantee(retval != 0, "just checking"); 1081 return retval; 1082 1083 #else 1084 #ifdef __FreeBSD__ 1085 retval = syscall(SYS_thr_self); 1086 #else 1087 #ifdef __OpenBSD__ 1088 retval = syscall(SYS_getthrid); 1089 #else 1090 #ifdef __NetBSD__ 1091 retval = (pid_t) syscall(SYS__lwp_self); 1092 #endif 1093 #endif 1094 #endif 1095 #endif 1096 1097 if (retval == -1) { 1098 return getpid(); 1099 } 1100 } 1101 1102 intx os::current_thread_id() { 1103 #ifdef __APPLE__ 1104 return (intx)::pthread_mach_thread_np(::pthread_self()); 1105 #else 1106 return (intx)::pthread_self(); 1107 #endif 1108 } 1109 1110 int os::current_process_id() { 1111 1112 // Under the old bsd thread library, bsd gives each thread 1113 // its own process id. Because of this each thread will return 1114 // a different pid if this method were to return the result 1115 // of getpid(2). Bsd provides no api that returns the pid 1116 // of the launcher thread for the vm. This implementation 1117 // returns a unique pid, the pid of the launcher thread 1118 // that starts the vm 'process'. 1119 1120 // Under the NPTL, getpid() returns the same pid as the 1121 // launcher thread rather than a unique pid per thread. 1122 // Use gettid() if you want the old pre NPTL behaviour. 1123 1124 // if you are looking for the result of a call to getpid() that 1125 // returns a unique pid for the calling thread, then look at the 1126 // OSThread::thread_id() method in osThread_bsd.hpp file 1127 1128 return (int)(_initial_pid ? _initial_pid : getpid()); 1129 } 1130 1131 // DLL functions 1132 1133 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1134 1135 // This must be hard coded because it's the system's temporary 1136 // directory not the java application's temp directory, ala java.io.tmpdir. 1137 #ifdef __APPLE__ 1138 // macosx has a secure per-user temporary directory 1139 char temp_path_storage[PATH_MAX]; 1140 const char* os::get_temp_directory() { 1141 static char *temp_path = NULL; 1142 if (temp_path == NULL) { 1143 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1144 if (pathSize == 0 || pathSize > PATH_MAX) { 1145 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1146 } 1147 temp_path = temp_path_storage; 1148 } 1149 return temp_path; 1150 } 1151 #else // __APPLE__ 1152 const char* os::get_temp_directory() { return "/tmp"; } 1153 #endif // __APPLE__ 1154 1155 // check if addr is inside libjvm.so 1156 bool os::address_is_in_vm(address addr) { 1157 static address libjvm_base_addr; 1158 Dl_info dlinfo; 1159 1160 if (libjvm_base_addr == NULL) { 1161 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1162 libjvm_base_addr = (address)dlinfo.dli_fbase; 1163 } 1164 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1165 } 1166 1167 if (dladdr((void *)addr, &dlinfo) != 0) { 1168 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1169 } 1170 1171 return false; 1172 } 1173 1174 1175 #define MACH_MAXSYMLEN 256 1176 1177 bool os::dll_address_to_function_name(address addr, char *buf, 1178 int buflen, int *offset, 1179 bool demangle) { 1180 // buf is not optional, but offset is optional 1181 assert(buf != NULL, "sanity check"); 1182 1183 Dl_info dlinfo; 1184 char localbuf[MACH_MAXSYMLEN]; 1185 1186 if (dladdr((void*)addr, &dlinfo) != 0) { 1187 // see if we have a matching symbol 1188 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1189 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) { 1190 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1191 } 1192 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1193 return true; 1194 } 1195 // no matching symbol so try for just file info 1196 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1197 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1198 buf, buflen, offset, dlinfo.dli_fname, demangle)) { 1199 return true; 1200 } 1201 } 1202 1203 // Handle non-dynamic manually: 1204 if (dlinfo.dli_fbase != NULL && 1205 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1206 dlinfo.dli_fbase)) { 1207 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) { 1208 jio_snprintf(buf, buflen, "%s", localbuf); 1209 } 1210 return true; 1211 } 1212 } 1213 buf[0] = '\0'; 1214 if (offset != NULL) *offset = -1; 1215 return false; 1216 } 1217 1218 // ported from solaris version 1219 bool os::dll_address_to_library_name(address addr, char* buf, 1220 int buflen, int* offset) { 1221 // buf is not optional, but offset is optional 1222 assert(buf != NULL, "sanity check"); 1223 1224 Dl_info dlinfo; 1225 1226 if (dladdr((void*)addr, &dlinfo) != 0) { 1227 if (dlinfo.dli_fname != NULL) { 1228 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1229 } 1230 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1231 *offset = addr - (address)dlinfo.dli_fbase; 1232 } 1233 return true; 1234 } 1235 1236 buf[0] = '\0'; 1237 if (offset) *offset = -1; 1238 return false; 1239 } 1240 1241 // Loads .dll/.so and 1242 // in case of error it checks if .dll/.so was built for the 1243 // same architecture as Hotspot is running on 1244 1245 #ifdef __APPLE__ 1246 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1247 #ifdef STATIC_BUILD 1248 return os::get_default_process_handle(); 1249 #else 1250 void * result= ::dlopen(filename, RTLD_LAZY); 1251 if (result != NULL) { 1252 // Successful loading 1253 return result; 1254 } 1255 1256 // Read system error message into ebuf 1257 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1258 ebuf[ebuflen-1]='\0'; 1259 1260 return NULL; 1261 #endif // STATIC_BUILD 1262 } 1263 #else 1264 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1265 #ifdef STATIC_BUILD 1266 return os::get_default_process_handle(); 1267 #else 1268 void * result= ::dlopen(filename, RTLD_LAZY); 1269 if (result != NULL) { 1270 // Successful loading 1271 return result; 1272 } 1273 1274 Elf32_Ehdr elf_head; 1275 1276 // Read system error message into ebuf 1277 // It may or may not be overwritten below 1278 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1279 ebuf[ebuflen-1]='\0'; 1280 int diag_msg_max_length=ebuflen-strlen(ebuf); 1281 char* diag_msg_buf=ebuf+strlen(ebuf); 1282 1283 if (diag_msg_max_length==0) { 1284 // No more space in ebuf for additional diagnostics message 1285 return NULL; 1286 } 1287 1288 1289 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1290 1291 if (file_descriptor < 0) { 1292 // Can't open library, report dlerror() message 1293 return NULL; 1294 } 1295 1296 bool failed_to_read_elf_head= 1297 (sizeof(elf_head)!= 1298 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1299 1300 ::close(file_descriptor); 1301 if (failed_to_read_elf_head) { 1302 // file i/o error - report dlerror() msg 1303 return NULL; 1304 } 1305 1306 typedef struct { 1307 Elf32_Half code; // Actual value as defined in elf.h 1308 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1309 char elf_class; // 32 or 64 bit 1310 char endianess; // MSB or LSB 1311 char* name; // String representation 1312 } arch_t; 1313 1314 #ifndef EM_486 1315 #define EM_486 6 /* Intel 80486 */ 1316 #endif 1317 1318 #ifndef EM_MIPS_RS3_LE 1319 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1320 #endif 1321 1322 #ifndef EM_PPC64 1323 #define EM_PPC64 21 /* PowerPC64 */ 1324 #endif 1325 1326 #ifndef EM_S390 1327 #define EM_S390 22 /* IBM System/390 */ 1328 #endif 1329 1330 #ifndef EM_IA_64 1331 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1332 #endif 1333 1334 #ifndef EM_X86_64 1335 #define EM_X86_64 62 /* AMD x86-64 */ 1336 #endif 1337 1338 static const arch_t arch_array[]={ 1339 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1340 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1341 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1342 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1343 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1344 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1345 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1346 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1347 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1348 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1349 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1350 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1351 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1352 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1353 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1354 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1355 }; 1356 1357 #if (defined IA32) 1358 static Elf32_Half running_arch_code=EM_386; 1359 #elif (defined AMD64) 1360 static Elf32_Half running_arch_code=EM_X86_64; 1361 #elif (defined IA64) 1362 static Elf32_Half running_arch_code=EM_IA_64; 1363 #elif (defined __sparc) && (defined _LP64) 1364 static Elf32_Half running_arch_code=EM_SPARCV9; 1365 #elif (defined __sparc) && (!defined _LP64) 1366 static Elf32_Half running_arch_code=EM_SPARC; 1367 #elif (defined __powerpc64__) 1368 static Elf32_Half running_arch_code=EM_PPC64; 1369 #elif (defined __powerpc__) 1370 static Elf32_Half running_arch_code=EM_PPC; 1371 #elif (defined ARM) 1372 static Elf32_Half running_arch_code=EM_ARM; 1373 #elif (defined S390) 1374 static Elf32_Half running_arch_code=EM_S390; 1375 #elif (defined ALPHA) 1376 static Elf32_Half running_arch_code=EM_ALPHA; 1377 #elif (defined MIPSEL) 1378 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1379 #elif (defined PARISC) 1380 static Elf32_Half running_arch_code=EM_PARISC; 1381 #elif (defined MIPS) 1382 static Elf32_Half running_arch_code=EM_MIPS; 1383 #elif (defined M68K) 1384 static Elf32_Half running_arch_code=EM_68K; 1385 #else 1386 #error Method os::dll_load requires that one of following is defined:\ 1387 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1388 #endif 1389 1390 // Identify compatability class for VM's architecture and library's architecture 1391 // Obtain string descriptions for architectures 1392 1393 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1394 int running_arch_index=-1; 1395 1396 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1397 if (running_arch_code == arch_array[i].code) { 1398 running_arch_index = i; 1399 } 1400 if (lib_arch.code == arch_array[i].code) { 1401 lib_arch.compat_class = arch_array[i].compat_class; 1402 lib_arch.name = arch_array[i].name; 1403 } 1404 } 1405 1406 assert(running_arch_index != -1, 1407 "Didn't find running architecture code (running_arch_code) in arch_array"); 1408 if (running_arch_index == -1) { 1409 // Even though running architecture detection failed 1410 // we may still continue with reporting dlerror() message 1411 return NULL; 1412 } 1413 1414 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1415 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1416 return NULL; 1417 } 1418 1419 #ifndef S390 1420 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1421 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1422 return NULL; 1423 } 1424 #endif // !S390 1425 1426 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1427 if (lib_arch.name!=NULL) { 1428 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1429 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1430 lib_arch.name, arch_array[running_arch_index].name); 1431 } else { 1432 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1433 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1434 lib_arch.code, 1435 arch_array[running_arch_index].name); 1436 } 1437 } 1438 1439 return NULL; 1440 #endif // STATIC_BUILD 1441 } 1442 #endif // !__APPLE__ 1443 1444 void* os::get_default_process_handle() { 1445 #ifdef __APPLE__ 1446 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1447 // to avoid finding unexpected symbols on second (or later) 1448 // loads of a library. 1449 return (void*)::dlopen(NULL, RTLD_FIRST); 1450 #else 1451 return (void*)::dlopen(NULL, RTLD_LAZY); 1452 #endif 1453 } 1454 1455 // XXX: Do we need a lock around this as per Linux? 1456 void* os::dll_lookup(void* handle, const char* name) { 1457 return dlsym(handle, name); 1458 } 1459 1460 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1461 outputStream * out = (outputStream *) param; 1462 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name); 1463 return 0; 1464 } 1465 1466 void os::print_dll_info(outputStream *st) { 1467 st->print_cr("Dynamic libraries:"); 1468 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1469 st->print_cr("Error: Cannot print dynamic libraries."); 1470 } 1471 } 1472 1473 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1474 #ifdef RTLD_DI_LINKMAP 1475 Dl_info dli; 1476 void *handle; 1477 Link_map *map; 1478 Link_map *p; 1479 1480 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1481 dli.dli_fname == NULL) { 1482 return 1; 1483 } 1484 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1485 if (handle == NULL) { 1486 return 1; 1487 } 1488 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1489 if (map == NULL) { 1490 dlclose(handle); 1491 return 1; 1492 } 1493 1494 while (map->l_prev != NULL) 1495 map = map->l_prev; 1496 1497 while (map != NULL) { 1498 // Value for top_address is returned as 0 since we don't have any information about module size 1499 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1500 dlclose(handle); 1501 return 1; 1502 } 1503 map = map->l_next; 1504 } 1505 1506 dlclose(handle); 1507 #elif defined(__APPLE__) 1508 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1509 // Value for top_address is returned as 0 since we don't have any information about module size 1510 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1511 return 1; 1512 } 1513 } 1514 return 0; 1515 #else 1516 return 1; 1517 #endif 1518 } 1519 1520 void os::get_summary_os_info(char* buf, size_t buflen) { 1521 // These buffers are small because we want this to be brief 1522 // and not use a lot of stack while generating the hs_err file. 1523 char os[100]; 1524 size_t size = sizeof(os); 1525 int mib_kern[] = { CTL_KERN, KERN_OSTYPE }; 1526 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) { 1527 #ifdef __APPLE__ 1528 strncpy(os, "Darwin", sizeof(os)); 1529 #elif __OpenBSD__ 1530 strncpy(os, "OpenBSD", sizeof(os)); 1531 #else 1532 strncpy(os, "BSD", sizeof(os)); 1533 #endif 1534 } 1535 1536 char release[100]; 1537 size = sizeof(release); 1538 int mib_release[] = { CTL_KERN, KERN_OSRELEASE }; 1539 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) { 1540 // if error, leave blank 1541 strncpy(release, "", sizeof(release)); 1542 } 1543 snprintf(buf, buflen, "%s %s", os, release); 1544 } 1545 1546 void os::print_os_info_brief(outputStream* st) { 1547 os::Posix::print_uname_info(st); 1548 } 1549 1550 void os::print_os_info(outputStream* st) { 1551 st->print("OS:"); 1552 1553 os::Posix::print_uname_info(st); 1554 1555 os::Posix::print_rlimit_info(st); 1556 1557 os::Posix::print_load_average(st); 1558 } 1559 1560 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) { 1561 // Nothing to do for now. 1562 } 1563 1564 void os::get_summary_cpu_info(char* buf, size_t buflen) { 1565 unsigned int mhz; 1566 size_t size = sizeof(mhz); 1567 int mib[] = { CTL_HW, HW_CPU_FREQ }; 1568 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) { 1569 mhz = 1; // looks like an error but can be divided by 1570 } else { 1571 mhz /= 1000000; // reported in millions 1572 } 1573 1574 char model[100]; 1575 size = sizeof(model); 1576 int mib_model[] = { CTL_HW, HW_MODEL }; 1577 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) { 1578 strncpy(model, cpu_arch, sizeof(model)); 1579 } 1580 1581 char machine[100]; 1582 size = sizeof(machine); 1583 int mib_machine[] = { CTL_HW, HW_MACHINE }; 1584 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) { 1585 strncpy(machine, "", sizeof(machine)); 1586 } 1587 1588 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz); 1589 } 1590 1591 void os::print_memory_info(outputStream* st) { 1592 1593 st->print("Memory:"); 1594 st->print(" %dk page", os::vm_page_size()>>10); 1595 1596 st->print(", physical " UINT64_FORMAT "k", 1597 os::physical_memory() >> 10); 1598 st->print("(" UINT64_FORMAT "k free)", 1599 os::available_memory() >> 10); 1600 st->cr(); 1601 } 1602 1603 static void print_signal_handler(outputStream* st, int sig, 1604 char* buf, size_t buflen); 1605 1606 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1607 st->print_cr("Signal Handlers:"); 1608 print_signal_handler(st, SIGSEGV, buf, buflen); 1609 print_signal_handler(st, SIGBUS , buf, buflen); 1610 print_signal_handler(st, SIGFPE , buf, buflen); 1611 print_signal_handler(st, SIGPIPE, buf, buflen); 1612 print_signal_handler(st, SIGXFSZ, buf, buflen); 1613 print_signal_handler(st, SIGILL , buf, buflen); 1614 print_signal_handler(st, SR_signum, buf, buflen); 1615 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1616 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1617 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1618 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1619 } 1620 1621 static char saved_jvm_path[MAXPATHLEN] = {0}; 1622 1623 // Find the full path to the current module, libjvm 1624 void os::jvm_path(char *buf, jint buflen) { 1625 // Error checking. 1626 if (buflen < MAXPATHLEN) { 1627 assert(false, "must use a large-enough buffer"); 1628 buf[0] = '\0'; 1629 return; 1630 } 1631 // Lazy resolve the path to current module. 1632 if (saved_jvm_path[0] != 0) { 1633 strcpy(buf, saved_jvm_path); 1634 return; 1635 } 1636 1637 char dli_fname[MAXPATHLEN]; 1638 bool ret = dll_address_to_library_name( 1639 CAST_FROM_FN_PTR(address, os::jvm_path), 1640 dli_fname, sizeof(dli_fname), NULL); 1641 assert(ret, "cannot locate libjvm"); 1642 char *rp = NULL; 1643 if (ret && dli_fname[0] != '\0') { 1644 rp = os::Posix::realpath(dli_fname, buf, buflen); 1645 } 1646 if (rp == NULL) { 1647 return; 1648 } 1649 1650 if (Arguments::sun_java_launcher_is_altjvm()) { 1651 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1652 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1653 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1654 // appears at the right place in the string, then assume we are 1655 // installed in a JDK and we're done. Otherwise, check for a 1656 // JAVA_HOME environment variable and construct a path to the JVM 1657 // being overridden. 1658 1659 const char *p = buf + strlen(buf) - 1; 1660 for (int count = 0; p > buf && count < 5; ++count) { 1661 for (--p; p > buf && *p != '/'; --p) 1662 /* empty */ ; 1663 } 1664 1665 if (strncmp(p, "/jre/lib/", 9) != 0) { 1666 // Look for JAVA_HOME in the environment. 1667 char* java_home_var = ::getenv("JAVA_HOME"); 1668 if (java_home_var != NULL && java_home_var[0] != 0) { 1669 char* jrelib_p; 1670 int len; 1671 1672 // Check the current module name "libjvm" 1673 p = strrchr(buf, '/'); 1674 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1675 1676 rp = os::Posix::realpath(java_home_var, buf, buflen); 1677 if (rp == NULL) { 1678 return; 1679 } 1680 1681 // determine if this is a legacy image or modules image 1682 // modules image doesn't have "jre" subdirectory 1683 len = strlen(buf); 1684 assert(len < buflen, "Ran out of buffer space"); 1685 jrelib_p = buf + len; 1686 1687 // Add the appropriate library subdir 1688 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1689 if (0 != access(buf, F_OK)) { 1690 snprintf(jrelib_p, buflen-len, "/lib"); 1691 } 1692 1693 // Add the appropriate client or server subdir 1694 len = strlen(buf); 1695 jrelib_p = buf + len; 1696 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1697 if (0 != access(buf, F_OK)) { 1698 snprintf(jrelib_p, buflen-len, "%s", ""); 1699 } 1700 1701 // If the path exists within JAVA_HOME, add the JVM library name 1702 // to complete the path to JVM being overridden. Otherwise fallback 1703 // to the path to the current library. 1704 if (0 == access(buf, F_OK)) { 1705 // Use current module name "libjvm" 1706 len = strlen(buf); 1707 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1708 } else { 1709 // Fall back to path of current library 1710 rp = os::Posix::realpath(dli_fname, buf, buflen); 1711 if (rp == NULL) { 1712 return; 1713 } 1714 } 1715 } 1716 } 1717 } 1718 1719 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1720 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1721 } 1722 1723 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1724 // no prefix required, not even "_" 1725 } 1726 1727 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1728 // no suffix required 1729 } 1730 1731 //////////////////////////////////////////////////////////////////////////////// 1732 // sun.misc.Signal support 1733 1734 static volatile jint sigint_count = 0; 1735 1736 static void UserHandler(int sig, void *siginfo, void *context) { 1737 // 4511530 - sem_post is serialized and handled by the manager thread. When 1738 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1739 // don't want to flood the manager thread with sem_post requests. 1740 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1741 return; 1742 } 1743 1744 // Ctrl-C is pressed during error reporting, likely because the error 1745 // handler fails to abort. Let VM die immediately. 1746 if (sig == SIGINT && VMError::is_error_reported()) { 1747 os::die(); 1748 } 1749 1750 os::signal_notify(sig); 1751 } 1752 1753 void* os::user_handler() { 1754 return CAST_FROM_FN_PTR(void*, UserHandler); 1755 } 1756 1757 extern "C" { 1758 typedef void (*sa_handler_t)(int); 1759 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1760 } 1761 1762 void* os::signal(int signal_number, void* handler) { 1763 struct sigaction sigAct, oldSigAct; 1764 1765 sigfillset(&(sigAct.sa_mask)); 1766 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1767 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1768 1769 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1770 // -1 means registration failed 1771 return (void *)-1; 1772 } 1773 1774 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1775 } 1776 1777 void os::signal_raise(int signal_number) { 1778 ::raise(signal_number); 1779 } 1780 1781 // The following code is moved from os.cpp for making this 1782 // code platform specific, which it is by its very nature. 1783 1784 // Will be modified when max signal is changed to be dynamic 1785 int os::sigexitnum_pd() { 1786 return NSIG; 1787 } 1788 1789 // a counter for each possible signal value 1790 static volatile jint pending_signals[NSIG+1] = { 0 }; 1791 static Semaphore* sig_sem = NULL; 1792 1793 static void jdk_misc_signal_init() { 1794 // Initialize signal structures 1795 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 1796 1797 // Initialize signal semaphore 1798 sig_sem = new Semaphore(); 1799 } 1800 1801 void os::signal_notify(int sig) { 1802 if (sig_sem != NULL) { 1803 Atomic::inc(&pending_signals[sig]); 1804 sig_sem->signal(); 1805 } else { 1806 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init 1807 // initialization isn't called. 1808 assert(ReduceSignalUsage, "signal semaphore should be created"); 1809 } 1810 } 1811 1812 static int check_pending_signals() { 1813 Atomic::store(0, &sigint_count); 1814 for (;;) { 1815 for (int i = 0; i < NSIG + 1; i++) { 1816 jint n = pending_signals[i]; 1817 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 1818 return i; 1819 } 1820 } 1821 JavaThread *thread = JavaThread::current(); 1822 ThreadBlockInVM tbivm(thread); 1823 1824 bool threadIsSuspended; 1825 do { 1826 thread->set_suspend_equivalent(); 1827 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 1828 sig_sem->wait(); 1829 1830 // were we externally suspended while we were waiting? 1831 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 1832 if (threadIsSuspended) { 1833 // The semaphore has been incremented, but while we were waiting 1834 // another thread suspended us. We don't want to continue running 1835 // while suspended because that would surprise the thread that 1836 // suspended us. 1837 sig_sem->signal(); 1838 1839 thread->java_suspend_self(); 1840 } 1841 } while (threadIsSuspended); 1842 } 1843 } 1844 1845 int os::signal_wait() { 1846 return check_pending_signals(); 1847 } 1848 1849 //////////////////////////////////////////////////////////////////////////////// 1850 // Virtual Memory 1851 1852 int os::vm_page_size() { 1853 // Seems redundant as all get out 1854 assert(os::Bsd::page_size() != -1, "must call os::init"); 1855 return os::Bsd::page_size(); 1856 } 1857 1858 // Solaris allocates memory by pages. 1859 int os::vm_allocation_granularity() { 1860 assert(os::Bsd::page_size() != -1, "must call os::init"); 1861 return os::Bsd::page_size(); 1862 } 1863 1864 // Rationale behind this function: 1865 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 1866 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 1867 // samples for JITted code. Here we create private executable mapping over the code cache 1868 // and then we can use standard (well, almost, as mapping can change) way to provide 1869 // info for the reporting script by storing timestamp and location of symbol 1870 void bsd_wrap_code(char* base, size_t size) { 1871 static volatile jint cnt = 0; 1872 1873 if (!UseOprofile) { 1874 return; 1875 } 1876 1877 char buf[PATH_MAX + 1]; 1878 int num = Atomic::add(1, &cnt); 1879 1880 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 1881 os::get_temp_directory(), os::current_process_id(), num); 1882 unlink(buf); 1883 1884 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 1885 1886 if (fd != -1) { 1887 off_t rv = ::lseek(fd, size-2, SEEK_SET); 1888 if (rv != (off_t)-1) { 1889 if (::write(fd, "", 1) == 1) { 1890 mmap(base, size, 1891 PROT_READ|PROT_WRITE|PROT_EXEC, 1892 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 1893 } 1894 } 1895 ::close(fd); 1896 unlink(buf); 1897 } 1898 } 1899 1900 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 1901 int err) { 1902 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT 1903 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec, 1904 os::errno_name(err), err); 1905 } 1906 1907 // NOTE: Bsd kernel does not really reserve the pages for us. 1908 // All it does is to check if there are enough free pages 1909 // left at the time of mmap(). This could be a potential 1910 // problem. 1911 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 1912 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 1913 #ifdef __OpenBSD__ 1914 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 1915 if (::mprotect(addr, size, prot) == 0) { 1916 return true; 1917 } 1918 #else 1919 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 1920 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 1921 if (res != (uintptr_t) MAP_FAILED) { 1922 return true; 1923 } 1924 #endif 1925 1926 // Warn about any commit errors we see in non-product builds just 1927 // in case mmap() doesn't work as described on the man page. 1928 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 1929 1930 return false; 1931 } 1932 1933 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 1934 bool exec) { 1935 // alignment_hint is ignored on this OS 1936 return pd_commit_memory(addr, size, exec); 1937 } 1938 1939 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 1940 const char* mesg) { 1941 assert(mesg != NULL, "mesg must be specified"); 1942 if (!pd_commit_memory(addr, size, exec)) { 1943 // add extra info in product mode for vm_exit_out_of_memory(): 1944 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 1945 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg); 1946 } 1947 } 1948 1949 void os::pd_commit_memory_or_exit(char* addr, size_t size, 1950 size_t alignment_hint, bool exec, 1951 const char* mesg) { 1952 // alignment_hint is ignored on this OS 1953 pd_commit_memory_or_exit(addr, size, exec, mesg); 1954 } 1955 1956 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1957 } 1958 1959 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 1960 ::madvise(addr, bytes, MADV_DONTNEED); 1961 } 1962 1963 void os::numa_make_global(char *addr, size_t bytes) { 1964 } 1965 1966 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 1967 } 1968 1969 bool os::numa_topology_changed() { return false; } 1970 1971 size_t os::numa_get_groups_num() { 1972 return 1; 1973 } 1974 1975 int os::numa_get_group_id() { 1976 return 0; 1977 } 1978 1979 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 1980 if (size > 0) { 1981 ids[0] = 0; 1982 return 1; 1983 } 1984 return 0; 1985 } 1986 1987 bool os::get_page_info(char *start, page_info* info) { 1988 return false; 1989 } 1990 1991 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 1992 return end; 1993 } 1994 1995 1996 bool os::pd_uncommit_memory(char* addr, size_t size) { 1997 #ifdef __OpenBSD__ 1998 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 1999 return ::mprotect(addr, size, PROT_NONE) == 0; 2000 #else 2001 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2002 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2003 return res != (uintptr_t) MAP_FAILED; 2004 #endif 2005 } 2006 2007 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2008 return os::commit_memory(addr, size, !ExecMem); 2009 } 2010 2011 // If this is a growable mapping, remove the guard pages entirely by 2012 // munmap()ping them. If not, just call uncommit_memory(). 2013 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2014 return os::uncommit_memory(addr, size); 2015 } 2016 2017 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2018 // at 'requested_addr'. If there are existing memory mappings at the same 2019 // location, however, they will be overwritten. If 'fixed' is false, 2020 // 'requested_addr' is only treated as a hint, the return value may or 2021 // may not start from the requested address. Unlike Bsd mmap(), this 2022 // function returns NULL to indicate failure. 2023 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2024 char * addr; 2025 int flags; 2026 2027 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2028 if (fixed) { 2029 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2030 flags |= MAP_FIXED; 2031 } 2032 2033 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2034 // touch an uncommitted page. Otherwise, the read/write might 2035 // succeed if we have enough swap space to back the physical page. 2036 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2037 flags, -1, 0); 2038 2039 return addr == MAP_FAILED ? NULL : addr; 2040 } 2041 2042 static int anon_munmap(char * addr, size_t size) { 2043 return ::munmap(addr, size) == 0; 2044 } 2045 2046 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2047 size_t alignment_hint) { 2048 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2049 } 2050 2051 bool os::pd_release_memory(char* addr, size_t size) { 2052 return anon_munmap(addr, size); 2053 } 2054 2055 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2056 // Bsd wants the mprotect address argument to be page aligned. 2057 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size()); 2058 2059 // According to SUSv3, mprotect() should only be used with mappings 2060 // established by mmap(), and mmap() always maps whole pages. Unaligned 2061 // 'addr' likely indicates problem in the VM (e.g. trying to change 2062 // protection of malloc'ed or statically allocated memory). Check the 2063 // caller if you hit this assert. 2064 assert(addr == bottom, "sanity check"); 2065 2066 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2067 return ::mprotect(bottom, size, prot) == 0; 2068 } 2069 2070 // Set protections specified 2071 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2072 bool is_committed) { 2073 unsigned int p = 0; 2074 switch (prot) { 2075 case MEM_PROT_NONE: p = PROT_NONE; break; 2076 case MEM_PROT_READ: p = PROT_READ; break; 2077 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2078 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2079 default: 2080 ShouldNotReachHere(); 2081 } 2082 // is_committed is unused. 2083 return bsd_mprotect(addr, bytes, p); 2084 } 2085 2086 bool os::guard_memory(char* addr, size_t size) { 2087 return bsd_mprotect(addr, size, PROT_NONE); 2088 } 2089 2090 bool os::unguard_memory(char* addr, size_t size) { 2091 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2092 } 2093 2094 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2095 return false; 2096 } 2097 2098 // Large page support 2099 2100 static size_t _large_page_size = 0; 2101 2102 void os::large_page_init() { 2103 } 2104 2105 2106 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2107 fatal("os::reserve_memory_special should not be called on BSD."); 2108 return NULL; 2109 } 2110 2111 bool os::release_memory_special(char* base, size_t bytes) { 2112 fatal("os::release_memory_special should not be called on BSD."); 2113 return false; 2114 } 2115 2116 size_t os::large_page_size() { 2117 return _large_page_size; 2118 } 2119 2120 bool os::can_commit_large_page_memory() { 2121 // Does not matter, we do not support huge pages. 2122 return false; 2123 } 2124 2125 bool os::can_execute_large_page_memory() { 2126 // Does not matter, we do not support huge pages. 2127 return false; 2128 } 2129 2130 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) { 2131 assert(file_desc >= 0, "file_desc is not valid"); 2132 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr); 2133 if (result != NULL) { 2134 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) { 2135 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory")); 2136 } 2137 } 2138 return result; 2139 } 2140 2141 // Reserve memory at an arbitrary address, only if that area is 2142 // available (and not reserved for something else). 2143 2144 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2145 const int max_tries = 10; 2146 char* base[max_tries]; 2147 size_t size[max_tries]; 2148 const size_t gap = 0x000000; 2149 2150 // Assert only that the size is a multiple of the page size, since 2151 // that's all that mmap requires, and since that's all we really know 2152 // about at this low abstraction level. If we need higher alignment, 2153 // we can either pass an alignment to this method or verify alignment 2154 // in one of the methods further up the call chain. See bug 5044738. 2155 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2156 2157 // Repeatedly allocate blocks until the block is allocated at the 2158 // right spot. 2159 2160 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2161 // if kernel honors the hint then we can return immediately. 2162 char * addr = anon_mmap(requested_addr, bytes, false); 2163 if (addr == requested_addr) { 2164 return requested_addr; 2165 } 2166 2167 if (addr != NULL) { 2168 // mmap() is successful but it fails to reserve at the requested address 2169 anon_munmap(addr, bytes); 2170 } 2171 2172 int i; 2173 for (i = 0; i < max_tries; ++i) { 2174 base[i] = reserve_memory(bytes); 2175 2176 if (base[i] != NULL) { 2177 // Is this the block we wanted? 2178 if (base[i] == requested_addr) { 2179 size[i] = bytes; 2180 break; 2181 } 2182 2183 // Does this overlap the block we wanted? Give back the overlapped 2184 // parts and try again. 2185 2186 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2187 if (top_overlap >= 0 && top_overlap < bytes) { 2188 unmap_memory(base[i], top_overlap); 2189 base[i] += top_overlap; 2190 size[i] = bytes - top_overlap; 2191 } else { 2192 size_t bottom_overlap = base[i] + bytes - requested_addr; 2193 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2194 unmap_memory(requested_addr, bottom_overlap); 2195 size[i] = bytes - bottom_overlap; 2196 } else { 2197 size[i] = bytes; 2198 } 2199 } 2200 } 2201 } 2202 2203 // Give back the unused reserved pieces. 2204 2205 for (int j = 0; j < i; ++j) { 2206 if (base[j] != NULL) { 2207 unmap_memory(base[j], size[j]); 2208 } 2209 } 2210 2211 if (i < max_tries) { 2212 return requested_addr; 2213 } else { 2214 return NULL; 2215 } 2216 } 2217 2218 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2219 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2220 } 2221 2222 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2223 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2224 } 2225 2226 void os::naked_short_sleep(jlong ms) { 2227 struct timespec req; 2228 2229 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2230 req.tv_sec = 0; 2231 if (ms > 0) { 2232 req.tv_nsec = (ms % 1000) * 1000000; 2233 } else { 2234 req.tv_nsec = 1; 2235 } 2236 2237 nanosleep(&req, NULL); 2238 2239 return; 2240 } 2241 2242 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2243 void os::infinite_sleep() { 2244 while (true) { // sleep forever ... 2245 ::sleep(100); // ... 100 seconds at a time 2246 } 2247 } 2248 2249 // Used to convert frequent JVM_Yield() to nops 2250 bool os::dont_yield() { 2251 return DontYieldALot; 2252 } 2253 2254 void os::naked_yield() { 2255 sched_yield(); 2256 } 2257 2258 //////////////////////////////////////////////////////////////////////////////// 2259 // thread priority support 2260 2261 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2262 // only supports dynamic priority, static priority must be zero. For real-time 2263 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2264 // However, for large multi-threaded applications, SCHED_RR is not only slower 2265 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2266 // of 5 runs - Sep 2005). 2267 // 2268 // The following code actually changes the niceness of kernel-thread/LWP. It 2269 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2270 // not the entire user process, and user level threads are 1:1 mapped to kernel 2271 // threads. It has always been the case, but could change in the future. For 2272 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2273 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2274 2275 #if !defined(__APPLE__) 2276 int os::java_to_os_priority[CriticalPriority + 1] = { 2277 19, // 0 Entry should never be used 2278 2279 0, // 1 MinPriority 2280 3, // 2 2281 6, // 3 2282 2283 10, // 4 2284 15, // 5 NormPriority 2285 18, // 6 2286 2287 21, // 7 2288 25, // 8 2289 28, // 9 NearMaxPriority 2290 2291 31, // 10 MaxPriority 2292 2293 31 // 11 CriticalPriority 2294 }; 2295 #else 2296 // Using Mach high-level priority assignments 2297 int os::java_to_os_priority[CriticalPriority + 1] = { 2298 0, // 0 Entry should never be used (MINPRI_USER) 2299 2300 27, // 1 MinPriority 2301 28, // 2 2302 29, // 3 2303 2304 30, // 4 2305 31, // 5 NormPriority (BASEPRI_DEFAULT) 2306 32, // 6 2307 2308 33, // 7 2309 34, // 8 2310 35, // 9 NearMaxPriority 2311 2312 36, // 10 MaxPriority 2313 2314 36 // 11 CriticalPriority 2315 }; 2316 #endif 2317 2318 static int prio_init() { 2319 if (ThreadPriorityPolicy == 1) { 2320 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2321 // if effective uid is not root. Perhaps, a more elegant way of doing 2322 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2323 if (geteuid() != 0) { 2324 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2325 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2326 } 2327 ThreadPriorityPolicy = 0; 2328 } 2329 } 2330 if (UseCriticalJavaThreadPriority) { 2331 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2332 } 2333 return 0; 2334 } 2335 2336 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2337 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2338 2339 #ifdef __OpenBSD__ 2340 // OpenBSD pthread_setprio starves low priority threads 2341 return OS_OK; 2342 #elif defined(__FreeBSD__) 2343 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2344 #elif defined(__APPLE__) || defined(__NetBSD__) 2345 struct sched_param sp; 2346 int policy; 2347 pthread_t self = pthread_self(); 2348 2349 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2350 return OS_ERR; 2351 } 2352 2353 sp.sched_priority = newpri; 2354 if (pthread_setschedparam(self, policy, &sp) != 0) { 2355 return OS_ERR; 2356 } 2357 2358 return OS_OK; 2359 #else 2360 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2361 return (ret == 0) ? OS_OK : OS_ERR; 2362 #endif 2363 } 2364 2365 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2366 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2367 *priority_ptr = java_to_os_priority[NormPriority]; 2368 return OS_OK; 2369 } 2370 2371 errno = 0; 2372 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2373 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2374 #elif defined(__APPLE__) || defined(__NetBSD__) 2375 int policy; 2376 struct sched_param sp; 2377 2378 pthread_getschedparam(pthread_self(), &policy, &sp); 2379 *priority_ptr = sp.sched_priority; 2380 #else 2381 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2382 #endif 2383 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2384 } 2385 2386 //////////////////////////////////////////////////////////////////////////////// 2387 // suspend/resume support 2388 2389 // The low-level signal-based suspend/resume support is a remnant from the 2390 // old VM-suspension that used to be for java-suspension, safepoints etc, 2391 // within hotspot. Currently used by JFR's OSThreadSampler 2392 // 2393 // The remaining code is greatly simplified from the more general suspension 2394 // code that used to be used. 2395 // 2396 // The protocol is quite simple: 2397 // - suspend: 2398 // - sends a signal to the target thread 2399 // - polls the suspend state of the osthread using a yield loop 2400 // - target thread signal handler (SR_handler) sets suspend state 2401 // and blocks in sigsuspend until continued 2402 // - resume: 2403 // - sets target osthread state to continue 2404 // - sends signal to end the sigsuspend loop in the SR_handler 2405 // 2406 // Note that the SR_lock plays no role in this suspend/resume protocol, 2407 // but is checked for NULL in SR_handler as a thread termination indicator. 2408 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs. 2409 // 2410 // Note that resume_clear_context() and suspend_save_context() are needed 2411 // by SR_handler(), so that fetch_frame_from_ucontext() works, 2412 // which in part is used by: 2413 // - Forte Analyzer: AsyncGetCallTrace() 2414 // - StackBanging: get_frame_at_stack_banging_point() 2415 2416 static void resume_clear_context(OSThread *osthread) { 2417 osthread->set_ucontext(NULL); 2418 osthread->set_siginfo(NULL); 2419 } 2420 2421 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2422 osthread->set_ucontext(context); 2423 osthread->set_siginfo(siginfo); 2424 } 2425 2426 // Handler function invoked when a thread's execution is suspended or 2427 // resumed. We have to be careful that only async-safe functions are 2428 // called here (Note: most pthread functions are not async safe and 2429 // should be avoided.) 2430 // 2431 // Note: sigwait() is a more natural fit than sigsuspend() from an 2432 // interface point of view, but sigwait() prevents the signal hander 2433 // from being run. libpthread would get very confused by not having 2434 // its signal handlers run and prevents sigwait()'s use with the 2435 // mutex granting granting signal. 2436 // 2437 // Currently only ever called on the VMThread or JavaThread 2438 // 2439 #ifdef __APPLE__ 2440 static OSXSemaphore sr_semaphore; 2441 #else 2442 static PosixSemaphore sr_semaphore; 2443 #endif 2444 2445 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2446 // Save and restore errno to avoid confusing native code with EINTR 2447 // after sigsuspend. 2448 int old_errno = errno; 2449 2450 Thread* thread = Thread::current_or_null_safe(); 2451 assert(thread != NULL, "Missing current thread in SR_handler"); 2452 2453 // On some systems we have seen signal delivery get "stuck" until the signal 2454 // mask is changed as part of thread termination. Check that the current thread 2455 // has not already terminated (via SR_lock()) - else the following assertion 2456 // will fail because the thread is no longer a JavaThread as the ~JavaThread 2457 // destructor has completed. 2458 2459 if (thread->SR_lock() == NULL) { 2460 return; 2461 } 2462 2463 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2464 2465 OSThread* osthread = thread->osthread(); 2466 2467 os::SuspendResume::State current = osthread->sr.state(); 2468 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2469 suspend_save_context(osthread, siginfo, context); 2470 2471 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2472 os::SuspendResume::State state = osthread->sr.suspended(); 2473 if (state == os::SuspendResume::SR_SUSPENDED) { 2474 sigset_t suspend_set; // signals for sigsuspend() 2475 2476 // get current set of blocked signals and unblock resume signal 2477 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2478 sigdelset(&suspend_set, SR_signum); 2479 2480 sr_semaphore.signal(); 2481 // wait here until we are resumed 2482 while (1) { 2483 sigsuspend(&suspend_set); 2484 2485 os::SuspendResume::State result = osthread->sr.running(); 2486 if (result == os::SuspendResume::SR_RUNNING) { 2487 sr_semaphore.signal(); 2488 break; 2489 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2490 ShouldNotReachHere(); 2491 } 2492 } 2493 2494 } else if (state == os::SuspendResume::SR_RUNNING) { 2495 // request was cancelled, continue 2496 } else { 2497 ShouldNotReachHere(); 2498 } 2499 2500 resume_clear_context(osthread); 2501 } else if (current == os::SuspendResume::SR_RUNNING) { 2502 // request was cancelled, continue 2503 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2504 // ignore 2505 } else { 2506 // ignore 2507 } 2508 2509 errno = old_errno; 2510 } 2511 2512 2513 static int SR_initialize() { 2514 struct sigaction act; 2515 char *s; 2516 // Get signal number to use for suspend/resume 2517 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2518 int sig = ::strtol(s, 0, 10); 2519 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769. 2520 sig < NSIG) { // Must be legal signal and fit into sigflags[]. 2521 SR_signum = sig; 2522 } else { 2523 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.", 2524 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum); 2525 } 2526 } 2527 2528 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2529 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2530 2531 sigemptyset(&SR_sigset); 2532 sigaddset(&SR_sigset, SR_signum); 2533 2534 // Set up signal handler for suspend/resume 2535 act.sa_flags = SA_RESTART|SA_SIGINFO; 2536 act.sa_handler = (void (*)(int)) SR_handler; 2537 2538 // SR_signum is blocked by default. 2539 // 4528190 - We also need to block pthread restart signal (32 on all 2540 // supported Bsd platforms). Note that BsdThreads need to block 2541 // this signal for all threads to work properly. So we don't have 2542 // to use hard-coded signal number when setting up the mask. 2543 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2544 2545 if (sigaction(SR_signum, &act, 0) == -1) { 2546 return -1; 2547 } 2548 2549 // Save signal flag 2550 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2551 return 0; 2552 } 2553 2554 static int sr_notify(OSThread* osthread) { 2555 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2556 assert_status(status == 0, status, "pthread_kill"); 2557 return status; 2558 } 2559 2560 // "Randomly" selected value for how long we want to spin 2561 // before bailing out on suspending a thread, also how often 2562 // we send a signal to a thread we want to resume 2563 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2564 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2565 2566 // returns true on success and false on error - really an error is fatal 2567 // but this seems the normal response to library errors 2568 static bool do_suspend(OSThread* osthread) { 2569 assert(osthread->sr.is_running(), "thread should be running"); 2570 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2571 2572 // mark as suspended and send signal 2573 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2574 // failed to switch, state wasn't running? 2575 ShouldNotReachHere(); 2576 return false; 2577 } 2578 2579 if (sr_notify(osthread) != 0) { 2580 ShouldNotReachHere(); 2581 } 2582 2583 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2584 while (true) { 2585 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2586 break; 2587 } else { 2588 // timeout 2589 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2590 if (cancelled == os::SuspendResume::SR_RUNNING) { 2591 return false; 2592 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2593 // make sure that we consume the signal on the semaphore as well 2594 sr_semaphore.wait(); 2595 break; 2596 } else { 2597 ShouldNotReachHere(); 2598 return false; 2599 } 2600 } 2601 } 2602 2603 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2604 return true; 2605 } 2606 2607 static void do_resume(OSThread* osthread) { 2608 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2609 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2610 2611 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2612 // failed to switch to WAKEUP_REQUEST 2613 ShouldNotReachHere(); 2614 return; 2615 } 2616 2617 while (true) { 2618 if (sr_notify(osthread) == 0) { 2619 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2620 if (osthread->sr.is_running()) { 2621 return; 2622 } 2623 } 2624 } else { 2625 ShouldNotReachHere(); 2626 } 2627 } 2628 2629 guarantee(osthread->sr.is_running(), "Must be running!"); 2630 } 2631 2632 /////////////////////////////////////////////////////////////////////////////////// 2633 // signal handling (except suspend/resume) 2634 2635 // This routine may be used by user applications as a "hook" to catch signals. 2636 // The user-defined signal handler must pass unrecognized signals to this 2637 // routine, and if it returns true (non-zero), then the signal handler must 2638 // return immediately. If the flag "abort_if_unrecognized" is true, then this 2639 // routine will never retun false (zero), but instead will execute a VM panic 2640 // routine kill the process. 2641 // 2642 // If this routine returns false, it is OK to call it again. This allows 2643 // the user-defined signal handler to perform checks either before or after 2644 // the VM performs its own checks. Naturally, the user code would be making 2645 // a serious error if it tried to handle an exception (such as a null check 2646 // or breakpoint) that the VM was generating for its own correct operation. 2647 // 2648 // This routine may recognize any of the following kinds of signals: 2649 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2650 // It should be consulted by handlers for any of those signals. 2651 // 2652 // The caller of this routine must pass in the three arguments supplied 2653 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 2654 // field of the structure passed to sigaction(). This routine assumes that 2655 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2656 // 2657 // Note that the VM will print warnings if it detects conflicting signal 2658 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2659 // 2660 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2661 void* ucontext, 2662 int abort_if_unrecognized); 2663 2664 static void signalHandler(int sig, siginfo_t* info, void* uc) { 2665 assert(info != NULL && uc != NULL, "it must be old kernel"); 2666 int orig_errno = errno; // Preserve errno value over signal handler. 2667 JVM_handle_bsd_signal(sig, info, uc, true); 2668 errno = orig_errno; 2669 } 2670 2671 2672 // This boolean allows users to forward their own non-matching signals 2673 // to JVM_handle_bsd_signal, harmlessly. 2674 bool os::Bsd::signal_handlers_are_installed = false; 2675 2676 // For signal-chaining 2677 struct sigaction sigact[NSIG]; 2678 uint32_t sigs = 0; 2679 #if (32 < NSIG-1) 2680 #error "Not all signals can be encoded in sigs. Adapt its type!" 2681 #endif 2682 bool os::Bsd::libjsig_is_loaded = false; 2683 typedef struct sigaction *(*get_signal_t)(int); 2684 get_signal_t os::Bsd::get_signal_action = NULL; 2685 2686 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2687 struct sigaction *actp = NULL; 2688 2689 if (libjsig_is_loaded) { 2690 // Retrieve the old signal handler from libjsig 2691 actp = (*get_signal_action)(sig); 2692 } 2693 if (actp == NULL) { 2694 // Retrieve the preinstalled signal handler from jvm 2695 actp = get_preinstalled_handler(sig); 2696 } 2697 2698 return actp; 2699 } 2700 2701 static bool call_chained_handler(struct sigaction *actp, int sig, 2702 siginfo_t *siginfo, void *context) { 2703 // Call the old signal handler 2704 if (actp->sa_handler == SIG_DFL) { 2705 // It's more reasonable to let jvm treat it as an unexpected exception 2706 // instead of taking the default action. 2707 return false; 2708 } else if (actp->sa_handler != SIG_IGN) { 2709 if ((actp->sa_flags & SA_NODEFER) == 0) { 2710 // automaticlly block the signal 2711 sigaddset(&(actp->sa_mask), sig); 2712 } 2713 2714 sa_handler_t hand; 2715 sa_sigaction_t sa; 2716 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 2717 // retrieve the chained handler 2718 if (siginfo_flag_set) { 2719 sa = actp->sa_sigaction; 2720 } else { 2721 hand = actp->sa_handler; 2722 } 2723 2724 if ((actp->sa_flags & SA_RESETHAND) != 0) { 2725 actp->sa_handler = SIG_DFL; 2726 } 2727 2728 // try to honor the signal mask 2729 sigset_t oset; 2730 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 2731 2732 // call into the chained handler 2733 if (siginfo_flag_set) { 2734 (*sa)(sig, siginfo, context); 2735 } else { 2736 (*hand)(sig); 2737 } 2738 2739 // restore the signal mask 2740 pthread_sigmask(SIG_SETMASK, &oset, 0); 2741 } 2742 // Tell jvm's signal handler the signal is taken care of. 2743 return true; 2744 } 2745 2746 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 2747 bool chained = false; 2748 // signal-chaining 2749 if (UseSignalChaining) { 2750 struct sigaction *actp = get_chained_signal_action(sig); 2751 if (actp != NULL) { 2752 chained = call_chained_handler(actp, sig, siginfo, context); 2753 } 2754 } 2755 return chained; 2756 } 2757 2758 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 2759 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) { 2760 return &sigact[sig]; 2761 } 2762 return NULL; 2763 } 2764 2765 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 2766 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2767 sigact[sig] = oldAct; 2768 sigs |= (uint32_t)1 << (sig-1); 2769 } 2770 2771 // for diagnostic 2772 int sigflags[NSIG]; 2773 2774 int os::Bsd::get_our_sigflags(int sig) { 2775 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2776 return sigflags[sig]; 2777 } 2778 2779 void os::Bsd::set_our_sigflags(int sig, int flags) { 2780 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2781 if (sig > 0 && sig < NSIG) { 2782 sigflags[sig] = flags; 2783 } 2784 } 2785 2786 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 2787 // Check for overwrite. 2788 struct sigaction oldAct; 2789 sigaction(sig, (struct sigaction*)NULL, &oldAct); 2790 2791 void* oldhand = oldAct.sa_sigaction 2792 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 2793 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 2794 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 2795 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 2796 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 2797 if (AllowUserSignalHandlers || !set_installed) { 2798 // Do not overwrite; user takes responsibility to forward to us. 2799 return; 2800 } else if (UseSignalChaining) { 2801 // save the old handler in jvm 2802 save_preinstalled_handler(sig, oldAct); 2803 // libjsig also interposes the sigaction() call below and saves the 2804 // old sigaction on it own. 2805 } else { 2806 fatal("Encountered unexpected pre-existing sigaction handler " 2807 "%#lx for signal %d.", (long)oldhand, sig); 2808 } 2809 } 2810 2811 struct sigaction sigAct; 2812 sigfillset(&(sigAct.sa_mask)); 2813 sigAct.sa_handler = SIG_DFL; 2814 if (!set_installed) { 2815 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 2816 } else { 2817 sigAct.sa_sigaction = signalHandler; 2818 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 2819 } 2820 #ifdef __APPLE__ 2821 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 2822 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 2823 // if the signal handler declares it will handle it on alternate stack. 2824 // Notice we only declare we will handle it on alt stack, but we are not 2825 // actually going to use real alt stack - this is just a workaround. 2826 // Please see ux_exception.c, method catch_mach_exception_raise for details 2827 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 2828 if (sig == SIGSEGV) { 2829 sigAct.sa_flags |= SA_ONSTACK; 2830 } 2831 #endif 2832 2833 // Save flags, which are set by ours 2834 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2835 sigflags[sig] = sigAct.sa_flags; 2836 2837 int ret = sigaction(sig, &sigAct, &oldAct); 2838 assert(ret == 0, "check"); 2839 2840 void* oldhand2 = oldAct.sa_sigaction 2841 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 2842 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 2843 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 2844 } 2845 2846 // install signal handlers for signals that HotSpot needs to 2847 // handle in order to support Java-level exception handling. 2848 2849 void os::Bsd::install_signal_handlers() { 2850 if (!signal_handlers_are_installed) { 2851 signal_handlers_are_installed = true; 2852 2853 // signal-chaining 2854 typedef void (*signal_setting_t)(); 2855 signal_setting_t begin_signal_setting = NULL; 2856 signal_setting_t end_signal_setting = NULL; 2857 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 2858 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 2859 if (begin_signal_setting != NULL) { 2860 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 2861 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 2862 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 2863 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 2864 libjsig_is_loaded = true; 2865 assert(UseSignalChaining, "should enable signal-chaining"); 2866 } 2867 if (libjsig_is_loaded) { 2868 // Tell libjsig jvm is setting signal handlers 2869 (*begin_signal_setting)(); 2870 } 2871 2872 set_signal_handler(SIGSEGV, true); 2873 set_signal_handler(SIGPIPE, true); 2874 set_signal_handler(SIGBUS, true); 2875 set_signal_handler(SIGILL, true); 2876 set_signal_handler(SIGFPE, true); 2877 set_signal_handler(SIGXFSZ, true); 2878 2879 #if defined(__APPLE__) 2880 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 2881 // signals caught and handled by the JVM. To work around this, we reset the mach task 2882 // signal handler that's placed on our process by CrashReporter. This disables 2883 // CrashReporter-based reporting. 2884 // 2885 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 2886 // on caught fatal signals. 2887 // 2888 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 2889 // handlers. By replacing the existing task exception handler, we disable gdb's mach 2890 // exception handling, while leaving the standard BSD signal handlers functional. 2891 kern_return_t kr; 2892 kr = task_set_exception_ports(mach_task_self(), 2893 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 2894 MACH_PORT_NULL, 2895 EXCEPTION_STATE_IDENTITY, 2896 MACHINE_THREAD_STATE); 2897 2898 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 2899 #endif 2900 2901 if (libjsig_is_loaded) { 2902 // Tell libjsig jvm finishes setting signal handlers 2903 (*end_signal_setting)(); 2904 } 2905 2906 // We don't activate signal checker if libjsig is in place, we trust ourselves 2907 // and if UserSignalHandler is installed all bets are off 2908 if (CheckJNICalls) { 2909 if (libjsig_is_loaded) { 2910 if (PrintJNIResolving) { 2911 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 2912 } 2913 check_signals = false; 2914 } 2915 if (AllowUserSignalHandlers) { 2916 if (PrintJNIResolving) { 2917 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 2918 } 2919 check_signals = false; 2920 } 2921 } 2922 } 2923 } 2924 2925 2926 ///// 2927 // glibc on Bsd platform uses non-documented flag 2928 // to indicate, that some special sort of signal 2929 // trampoline is used. 2930 // We will never set this flag, and we should 2931 // ignore this flag in our diagnostic 2932 #ifdef SIGNIFICANT_SIGNAL_MASK 2933 #undef SIGNIFICANT_SIGNAL_MASK 2934 #endif 2935 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 2936 2937 static const char* get_signal_handler_name(address handler, 2938 char* buf, int buflen) { 2939 int offset; 2940 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 2941 if (found) { 2942 // skip directory names 2943 const char *p1, *p2; 2944 p1 = buf; 2945 size_t len = strlen(os::file_separator()); 2946 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 2947 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 2948 } else { 2949 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 2950 } 2951 return buf; 2952 } 2953 2954 static void print_signal_handler(outputStream* st, int sig, 2955 char* buf, size_t buflen) { 2956 struct sigaction sa; 2957 2958 sigaction(sig, NULL, &sa); 2959 2960 // See comment for SIGNIFICANT_SIGNAL_MASK define 2961 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 2962 2963 st->print("%s: ", os::exception_name(sig, buf, buflen)); 2964 2965 address handler = (sa.sa_flags & SA_SIGINFO) 2966 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 2967 : CAST_FROM_FN_PTR(address, sa.sa_handler); 2968 2969 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 2970 st->print("SIG_DFL"); 2971 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 2972 st->print("SIG_IGN"); 2973 } else { 2974 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 2975 } 2976 2977 st->print(", sa_mask[0]="); 2978 os::Posix::print_signal_set_short(st, &sa.sa_mask); 2979 2980 address rh = VMError::get_resetted_sighandler(sig); 2981 // May be, handler was resetted by VMError? 2982 if (rh != NULL) { 2983 handler = rh; 2984 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 2985 } 2986 2987 st->print(", sa_flags="); 2988 os::Posix::print_sa_flags(st, sa.sa_flags); 2989 2990 // Check: is it our handler? 2991 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 2992 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 2993 // It is our signal handler 2994 // check for flags, reset system-used one! 2995 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 2996 st->print( 2997 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 2998 os::Bsd::get_our_sigflags(sig)); 2999 } 3000 } 3001 st->cr(); 3002 } 3003 3004 3005 #define DO_SIGNAL_CHECK(sig) \ 3006 do { \ 3007 if (!sigismember(&check_signal_done, sig)) { \ 3008 os::Bsd::check_signal_handler(sig); \ 3009 } \ 3010 } while (0) 3011 3012 // This method is a periodic task to check for misbehaving JNI applications 3013 // under CheckJNI, we can add any periodic checks here 3014 3015 void os::run_periodic_checks() { 3016 3017 if (check_signals == false) return; 3018 3019 // SEGV and BUS if overridden could potentially prevent 3020 // generation of hs*.log in the event of a crash, debugging 3021 // such a case can be very challenging, so we absolutely 3022 // check the following for a good measure: 3023 DO_SIGNAL_CHECK(SIGSEGV); 3024 DO_SIGNAL_CHECK(SIGILL); 3025 DO_SIGNAL_CHECK(SIGFPE); 3026 DO_SIGNAL_CHECK(SIGBUS); 3027 DO_SIGNAL_CHECK(SIGPIPE); 3028 DO_SIGNAL_CHECK(SIGXFSZ); 3029 3030 3031 // ReduceSignalUsage allows the user to override these handlers 3032 // see comments at the very top and jvm_md.h 3033 if (!ReduceSignalUsage) { 3034 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3035 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3036 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3037 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3038 } 3039 3040 DO_SIGNAL_CHECK(SR_signum); 3041 } 3042 3043 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3044 3045 static os_sigaction_t os_sigaction = NULL; 3046 3047 void os::Bsd::check_signal_handler(int sig) { 3048 char buf[O_BUFLEN]; 3049 address jvmHandler = NULL; 3050 3051 3052 struct sigaction act; 3053 if (os_sigaction == NULL) { 3054 // only trust the default sigaction, in case it has been interposed 3055 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3056 if (os_sigaction == NULL) return; 3057 } 3058 3059 os_sigaction(sig, (struct sigaction*)NULL, &act); 3060 3061 3062 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3063 3064 address thisHandler = (act.sa_flags & SA_SIGINFO) 3065 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3066 : CAST_FROM_FN_PTR(address, act.sa_handler); 3067 3068 3069 switch (sig) { 3070 case SIGSEGV: 3071 case SIGBUS: 3072 case SIGFPE: 3073 case SIGPIPE: 3074 case SIGILL: 3075 case SIGXFSZ: 3076 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3077 break; 3078 3079 case SHUTDOWN1_SIGNAL: 3080 case SHUTDOWN2_SIGNAL: 3081 case SHUTDOWN3_SIGNAL: 3082 case BREAK_SIGNAL: 3083 jvmHandler = (address)user_handler(); 3084 break; 3085 3086 default: 3087 if (sig == SR_signum) { 3088 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3089 } else { 3090 return; 3091 } 3092 break; 3093 } 3094 3095 if (thisHandler != jvmHandler) { 3096 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3097 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3098 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3099 // No need to check this sig any longer 3100 sigaddset(&check_signal_done, sig); 3101 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3102 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3103 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3104 exception_name(sig, buf, O_BUFLEN)); 3105 } 3106 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3107 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3108 tty->print("expected:"); 3109 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig)); 3110 tty->cr(); 3111 tty->print(" found:"); 3112 os::Posix::print_sa_flags(tty, act.sa_flags); 3113 tty->cr(); 3114 // No need to check this sig any longer 3115 sigaddset(&check_signal_done, sig); 3116 } 3117 3118 // Dump all the signal 3119 if (sigismember(&check_signal_done, sig)) { 3120 print_signal_handlers(tty, buf, O_BUFLEN); 3121 } 3122 } 3123 3124 extern void report_error(char* file_name, int line_no, char* title, 3125 char* format, ...); 3126 3127 // this is called _before_ the most of global arguments have been parsed 3128 void os::init(void) { 3129 char dummy; // used to get a guess on initial stack address 3130 3131 // With BsdThreads the JavaMain thread pid (primordial thread) 3132 // is different than the pid of the java launcher thread. 3133 // So, on Bsd, the launcher thread pid is passed to the VM 3134 // via the sun.java.launcher.pid property. 3135 // Use this property instead of getpid() if it was correctly passed. 3136 // See bug 6351349. 3137 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3138 3139 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3140 3141 clock_tics_per_sec = CLK_TCK; 3142 3143 init_random(1234567); 3144 3145 Bsd::set_page_size(getpagesize()); 3146 if (Bsd::page_size() == -1) { 3147 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno)); 3148 } 3149 init_page_sizes((size_t) Bsd::page_size()); 3150 3151 Bsd::initialize_system_info(); 3152 3153 // _main_thread points to the thread that created/loaded the JVM. 3154 Bsd::_main_thread = pthread_self(); 3155 3156 Bsd::clock_init(); 3157 initial_time_count = javaTimeNanos(); 3158 3159 #ifdef __APPLE__ 3160 // XXXDARWIN 3161 // Work around the unaligned VM callbacks in hotspot's 3162 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3163 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3164 // alignment when doing symbol lookup. To work around this, we force early 3165 // binding of all symbols now, thus binding when alignment is known-good. 3166 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3167 #endif 3168 3169 os::Posix::init(); 3170 } 3171 3172 // To install functions for atexit system call 3173 extern "C" { 3174 static void perfMemory_exit_helper() { 3175 perfMemory_exit(); 3176 } 3177 } 3178 3179 // this is called _after_ the global arguments have been parsed 3180 jint os::init_2(void) { 3181 3182 os::Posix::init_2(); 3183 3184 // initialize suspend/resume support - must do this before signal_sets_init() 3185 if (SR_initialize() != 0) { 3186 perror("SR_initialize failed"); 3187 return JNI_ERR; 3188 } 3189 3190 Bsd::signal_sets_init(); 3191 Bsd::install_signal_handlers(); 3192 // Initialize data for jdk.internal.misc.Signal 3193 if (!ReduceSignalUsage) { 3194 jdk_misc_signal_init(); 3195 } 3196 3197 // Check and sets minimum stack sizes against command line options 3198 if (Posix::set_minimum_stack_sizes() == JNI_ERR) { 3199 return JNI_ERR; 3200 } 3201 3202 if (MaxFDLimit) { 3203 // set the number of file descriptors to max. print out error 3204 // if getrlimit/setrlimit fails but continue regardless. 3205 struct rlimit nbr_files; 3206 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3207 if (status != 0) { 3208 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno)); 3209 } else { 3210 nbr_files.rlim_cur = nbr_files.rlim_max; 3211 3212 #ifdef __APPLE__ 3213 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3214 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3215 // be used instead 3216 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3217 #endif 3218 3219 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3220 if (status != 0) { 3221 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno)); 3222 } 3223 } 3224 } 3225 3226 // at-exit methods are called in the reverse order of their registration. 3227 // atexit functions are called on return from main or as a result of a 3228 // call to exit(3C). There can be only 32 of these functions registered 3229 // and atexit() does not set errno. 3230 3231 if (PerfAllowAtExitRegistration) { 3232 // only register atexit functions if PerfAllowAtExitRegistration is set. 3233 // atexit functions can be delayed until process exit time, which 3234 // can be problematic for embedded VM situations. Embedded VMs should 3235 // call DestroyJavaVM() to assure that VM resources are released. 3236 3237 // note: perfMemory_exit_helper atexit function may be removed in 3238 // the future if the appropriate cleanup code can be added to the 3239 // VM_Exit VMOperation's doit method. 3240 if (atexit(perfMemory_exit_helper) != 0) { 3241 warning("os::init_2 atexit(perfMemory_exit_helper) failed"); 3242 } 3243 } 3244 3245 // initialize thread priority policy 3246 prio_init(); 3247 3248 #ifdef __APPLE__ 3249 // dynamically link to objective c gc registration 3250 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3251 if (handleLibObjc != NULL) { 3252 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3253 } 3254 #endif 3255 3256 return JNI_OK; 3257 } 3258 3259 // Mark the polling page as unreadable 3260 void os::make_polling_page_unreadable(void) { 3261 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3262 fatal("Could not disable polling page"); 3263 } 3264 } 3265 3266 // Mark the polling page as readable 3267 void os::make_polling_page_readable(void) { 3268 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3269 fatal("Could not enable polling page"); 3270 } 3271 } 3272 3273 int os::active_processor_count() { 3274 // User has overridden the number of active processors 3275 if (ActiveProcessorCount > 0) { 3276 log_trace(os)("active_processor_count: " 3277 "active processor count set by user : %d", 3278 ActiveProcessorCount); 3279 return ActiveProcessorCount; 3280 } 3281 3282 return _processor_count; 3283 } 3284 3285 void os::set_native_thread_name(const char *name) { 3286 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3287 // This is only supported in Snow Leopard and beyond 3288 if (name != NULL) { 3289 // Add a "Java: " prefix to the name 3290 char buf[MAXTHREADNAMESIZE]; 3291 snprintf(buf, sizeof(buf), "Java: %s", name); 3292 pthread_setname_np(buf); 3293 } 3294 #endif 3295 } 3296 3297 bool os::distribute_processes(uint length, uint* distribution) { 3298 // Not yet implemented. 3299 return false; 3300 } 3301 3302 bool os::bind_to_processor(uint processor_id) { 3303 // Not yet implemented. 3304 return false; 3305 } 3306 3307 void os::SuspendedThreadTask::internal_do_task() { 3308 if (do_suspend(_thread->osthread())) { 3309 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3310 do_task(context); 3311 do_resume(_thread->osthread()); 3312 } 3313 } 3314 3315 //////////////////////////////////////////////////////////////////////////////// 3316 // debug support 3317 3318 bool os::find(address addr, outputStream* st) { 3319 Dl_info dlinfo; 3320 memset(&dlinfo, 0, sizeof(dlinfo)); 3321 if (dladdr(addr, &dlinfo) != 0) { 3322 st->print(INTPTR_FORMAT ": ", (intptr_t)addr); 3323 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3324 st->print("%s+%#x", dlinfo.dli_sname, 3325 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr)); 3326 } else if (dlinfo.dli_fbase != NULL) { 3327 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase)); 3328 } else { 3329 st->print("<absolute address>"); 3330 } 3331 if (dlinfo.dli_fname != NULL) { 3332 st->print(" in %s", dlinfo.dli_fname); 3333 } 3334 if (dlinfo.dli_fbase != NULL) { 3335 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase); 3336 } 3337 st->cr(); 3338 3339 if (Verbose) { 3340 // decode some bytes around the PC 3341 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3342 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3343 address lowest = (address) dlinfo.dli_sname; 3344 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3345 if (begin < lowest) begin = lowest; 3346 Dl_info dlinfo2; 3347 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3348 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3349 end = (address) dlinfo2.dli_saddr; 3350 } 3351 Disassembler::decode(begin, end, st); 3352 } 3353 return true; 3354 } 3355 return false; 3356 } 3357 3358 //////////////////////////////////////////////////////////////////////////////// 3359 // misc 3360 3361 // This does not do anything on Bsd. This is basically a hook for being 3362 // able to use structured exception handling (thread-local exception filters) 3363 // on, e.g., Win32. 3364 void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3365 const methodHandle& method, JavaCallArguments* args, 3366 Thread* thread) { 3367 f(value, method, args, thread); 3368 } 3369 3370 void os::print_statistics() { 3371 } 3372 3373 bool os::message_box(const char* title, const char* message) { 3374 int i; 3375 fdStream err(defaultStream::error_fd()); 3376 for (i = 0; i < 78; i++) err.print_raw("="); 3377 err.cr(); 3378 err.print_raw_cr(title); 3379 for (i = 0; i < 78; i++) err.print_raw("-"); 3380 err.cr(); 3381 err.print_raw_cr(message); 3382 for (i = 0; i < 78; i++) err.print_raw("="); 3383 err.cr(); 3384 3385 char buf[16]; 3386 // Prevent process from exiting upon "read error" without consuming all CPU 3387 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3388 3389 return buf[0] == 'y' || buf[0] == 'Y'; 3390 } 3391 3392 static inline struct timespec get_mtime(const char* filename) { 3393 struct stat st; 3394 int ret = os::stat(filename, &st); 3395 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno)); 3396 #ifdef __APPLE__ 3397 return st.st_mtimespec; 3398 #else 3399 return st.st_mtim; 3400 #endif 3401 } 3402 3403 int os::compare_file_modified_times(const char* file1, const char* file2) { 3404 struct timespec filetime1 = get_mtime(file1); 3405 struct timespec filetime2 = get_mtime(file2); 3406 int diff = filetime1.tv_sec - filetime2.tv_sec; 3407 if (diff == 0) { 3408 return filetime1.tv_nsec - filetime2.tv_nsec; 3409 } 3410 return diff; 3411 } 3412 3413 // Is a (classpath) directory empty? 3414 bool os::dir_is_empty(const char* path) { 3415 DIR *dir = NULL; 3416 struct dirent *ptr; 3417 3418 dir = opendir(path); 3419 if (dir == NULL) return true; 3420 3421 // Scan the directory 3422 bool result = true; 3423 while (result && (ptr = readdir(dir)) != NULL) { 3424 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3425 result = false; 3426 } 3427 } 3428 closedir(dir); 3429 return result; 3430 } 3431 3432 // This code originates from JDK's sysOpen and open64_w 3433 // from src/solaris/hpi/src/system_md.c 3434 3435 int os::open(const char *path, int oflag, int mode) { 3436 if (strlen(path) > MAX_PATH - 1) { 3437 errno = ENAMETOOLONG; 3438 return -1; 3439 } 3440 int fd; 3441 3442 fd = ::open(path, oflag, mode); 3443 if (fd == -1) return -1; 3444 3445 // If the open succeeded, the file might still be a directory 3446 { 3447 struct stat buf; 3448 int ret = ::fstat(fd, &buf); 3449 int st_mode = buf.st_mode; 3450 3451 if (ret != -1) { 3452 if ((st_mode & S_IFMT) == S_IFDIR) { 3453 errno = EISDIR; 3454 ::close(fd); 3455 return -1; 3456 } 3457 } else { 3458 ::close(fd); 3459 return -1; 3460 } 3461 } 3462 3463 // All file descriptors that are opened in the JVM and not 3464 // specifically destined for a subprocess should have the 3465 // close-on-exec flag set. If we don't set it, then careless 3rd 3466 // party native code might fork and exec without closing all 3467 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3468 // UNIXProcess.c), and this in turn might: 3469 // 3470 // - cause end-of-file to fail to be detected on some file 3471 // descriptors, resulting in mysterious hangs, or 3472 // 3473 // - might cause an fopen in the subprocess to fail on a system 3474 // suffering from bug 1085341. 3475 // 3476 // (Yes, the default setting of the close-on-exec flag is a Unix 3477 // design flaw) 3478 // 3479 // See: 3480 // 1085341: 32-bit stdio routines should support file descriptors >255 3481 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3482 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3483 // 3484 #ifdef FD_CLOEXEC 3485 { 3486 int flags = ::fcntl(fd, F_GETFD); 3487 if (flags != -1) { 3488 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3489 } 3490 } 3491 #endif 3492 3493 return fd; 3494 } 3495 3496 3497 // create binary file, rewriting existing file if required 3498 int os::create_binary_file(const char* path, bool rewrite_existing) { 3499 int oflags = O_WRONLY | O_CREAT; 3500 if (!rewrite_existing) { 3501 oflags |= O_EXCL; 3502 } 3503 return ::open(path, oflags, S_IREAD | S_IWRITE); 3504 } 3505 3506 // return current position of file pointer 3507 jlong os::current_file_offset(int fd) { 3508 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3509 } 3510 3511 // move file pointer to the specified offset 3512 jlong os::seek_to_file_offset(int fd, jlong offset) { 3513 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3514 } 3515 3516 // This code originates from JDK's sysAvailable 3517 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3518 3519 int os::available(int fd, jlong *bytes) { 3520 jlong cur, end; 3521 int mode; 3522 struct stat buf; 3523 3524 if (::fstat(fd, &buf) >= 0) { 3525 mode = buf.st_mode; 3526 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3527 int n; 3528 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3529 *bytes = n; 3530 return 1; 3531 } 3532 } 3533 } 3534 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3535 return 0; 3536 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3537 return 0; 3538 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3539 return 0; 3540 } 3541 *bytes = end - cur; 3542 return 1; 3543 } 3544 3545 // Map a block of memory. 3546 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3547 char *addr, size_t bytes, bool read_only, 3548 bool allow_exec) { 3549 int prot; 3550 int flags; 3551 3552 if (read_only) { 3553 prot = PROT_READ; 3554 flags = MAP_SHARED; 3555 } else { 3556 prot = PROT_READ | PROT_WRITE; 3557 flags = MAP_PRIVATE; 3558 } 3559 3560 if (allow_exec) { 3561 prot |= PROT_EXEC; 3562 } 3563 3564 if (addr != NULL) { 3565 flags |= MAP_FIXED; 3566 } 3567 3568 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3569 fd, file_offset); 3570 if (mapped_address == MAP_FAILED) { 3571 return NULL; 3572 } 3573 return mapped_address; 3574 } 3575 3576 3577 // Remap a block of memory. 3578 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3579 char *addr, size_t bytes, bool read_only, 3580 bool allow_exec) { 3581 // same as map_memory() on this OS 3582 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3583 allow_exec); 3584 } 3585 3586 3587 // Unmap a block of memory. 3588 bool os::pd_unmap_memory(char* addr, size_t bytes) { 3589 return munmap(addr, bytes) == 0; 3590 } 3591 3592 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3593 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 3594 // of a thread. 3595 // 3596 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 3597 // the fast estimate available on the platform. 3598 3599 jlong os::current_thread_cpu_time() { 3600 #ifdef __APPLE__ 3601 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 3602 #else 3603 Unimplemented(); 3604 return 0; 3605 #endif 3606 } 3607 3608 jlong os::thread_cpu_time(Thread* thread) { 3609 #ifdef __APPLE__ 3610 return os::thread_cpu_time(thread, true /* user + sys */); 3611 #else 3612 Unimplemented(); 3613 return 0; 3614 #endif 3615 } 3616 3617 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 3618 #ifdef __APPLE__ 3619 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 3620 #else 3621 Unimplemented(); 3622 return 0; 3623 #endif 3624 } 3625 3626 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 3627 #ifdef __APPLE__ 3628 struct thread_basic_info tinfo; 3629 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 3630 kern_return_t kr; 3631 thread_t mach_thread; 3632 3633 mach_thread = thread->osthread()->thread_id(); 3634 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 3635 if (kr != KERN_SUCCESS) { 3636 return -1; 3637 } 3638 3639 if (user_sys_cpu_time) { 3640 jlong nanos; 3641 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 3642 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 3643 return nanos; 3644 } else { 3645 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 3646 } 3647 #else 3648 Unimplemented(); 3649 return 0; 3650 #endif 3651 } 3652 3653 3654 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3655 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3656 info_ptr->may_skip_backward = false; // elapsed time not wall time 3657 info_ptr->may_skip_forward = false; // elapsed time not wall time 3658 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3659 } 3660 3661 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3662 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3663 info_ptr->may_skip_backward = false; // elapsed time not wall time 3664 info_ptr->may_skip_forward = false; // elapsed time not wall time 3665 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3666 } 3667 3668 bool os::is_thread_cpu_time_supported() { 3669 #ifdef __APPLE__ 3670 return true; 3671 #else 3672 return false; 3673 #endif 3674 } 3675 3676 // System loadavg support. Returns -1 if load average cannot be obtained. 3677 // Bsd doesn't yet have a (official) notion of processor sets, 3678 // so just return the system wide load average. 3679 int os::loadavg(double loadavg[], int nelem) { 3680 return ::getloadavg(loadavg, nelem); 3681 } 3682 3683 void os::pause() { 3684 char filename[MAX_PATH]; 3685 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 3686 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 3687 } else { 3688 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 3689 } 3690 3691 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 3692 if (fd != -1) { 3693 struct stat buf; 3694 ::close(fd); 3695 while (::stat(filename, &buf) == 0) { 3696 (void)::poll(NULL, 0, 100); 3697 } 3698 } else { 3699 jio_fprintf(stderr, 3700 "Could not open pause file '%s', continuing immediately.\n", filename); 3701 } 3702 } 3703 3704 // Darwin has no "environ" in a dynamic library. 3705 #ifdef __APPLE__ 3706 #include <crt_externs.h> 3707 #define environ (*_NSGetEnviron()) 3708 #else 3709 extern char** environ; 3710 #endif 3711 3712 // Run the specified command in a separate process. Return its exit value, 3713 // or -1 on failure (e.g. can't fork a new process). 3714 // Unlike system(), this function can be called from signal handler. It 3715 // doesn't block SIGINT et al. 3716 int os::fork_and_exec(char* cmd) { 3717 const char * argv[4] = {"sh", "-c", cmd, NULL}; 3718 3719 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 3720 // pthread_atfork handlers and reset pthread library. All we need is a 3721 // separate process to execve. Make a direct syscall to fork process. 3722 // On IA64 there's no fork syscall, we have to use fork() and hope for 3723 // the best... 3724 pid_t pid = fork(); 3725 3726 if (pid < 0) { 3727 // fork failed 3728 return -1; 3729 3730 } else if (pid == 0) { 3731 // child process 3732 3733 // execve() in BsdThreads will call pthread_kill_other_threads_np() 3734 // first to kill every thread on the thread list. Because this list is 3735 // not reset by fork() (see notes above), execve() will instead kill 3736 // every thread in the parent process. We know this is the only thread 3737 // in the new process, so make a system call directly. 3738 // IA64 should use normal execve() from glibc to match the glibc fork() 3739 // above. 3740 execve("/bin/sh", (char* const*)argv, environ); 3741 3742 // execve failed 3743 _exit(-1); 3744 3745 } else { 3746 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 3747 // care about the actual exit code, for now. 3748 3749 int status; 3750 3751 // Wait for the child process to exit. This returns immediately if 3752 // the child has already exited. */ 3753 while (waitpid(pid, &status, 0) < 0) { 3754 switch (errno) { 3755 case ECHILD: return 0; 3756 case EINTR: break; 3757 default: return -1; 3758 } 3759 } 3760 3761 if (WIFEXITED(status)) { 3762 // The child exited normally; get its exit code. 3763 return WEXITSTATUS(status); 3764 } else if (WIFSIGNALED(status)) { 3765 // The child exited because of a signal 3766 // The best value to return is 0x80 + signal number, 3767 // because that is what all Unix shells do, and because 3768 // it allows callers to distinguish between process exit and 3769 // process death by signal. 3770 return 0x80 + WTERMSIG(status); 3771 } else { 3772 // Unknown exit code; pass it through 3773 return status; 3774 } 3775 } 3776 } 3777 3778 // Get the default path to the core file 3779 // Returns the length of the string 3780 int os::get_core_path(char* buffer, size_t bufferSize) { 3781 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 3782 3783 // Truncate if theoretical string was longer than bufferSize 3784 n = MIN2(n, (int)bufferSize); 3785 3786 return n; 3787 } 3788 3789 #ifndef PRODUCT 3790 void TestReserveMemorySpecial_test() { 3791 // No tests available for this platform 3792 } 3793 #endif 3794 3795 bool os::start_debugging(char *buf, int buflen) { 3796 int len = (int)strlen(buf); 3797 char *p = &buf[len]; 3798 3799 jio_snprintf(p, buflen-len, 3800 "\n\n" 3801 "Do you want to debug the problem?\n\n" 3802 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n" 3803 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n" 3804 "Otherwise, press RETURN to abort...", 3805 os::current_process_id(), os::current_process_id(), 3806 os::current_thread_id(), os::current_thread_id()); 3807 3808 bool yes = os::message_box("Unexpected Error", buf); 3809 3810 if (yes) { 3811 // yes, user asked VM to launch debugger 3812 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d", 3813 os::current_process_id(), os::current_process_id()); 3814 3815 os::fork_and_exec(buf); 3816 yes = false; 3817 } 3818 return yes; 3819 }