1 /* 2 * Copyright (c) 1999, 2017, 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.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.inline.hpp" 53 #include "runtime/osThread.hpp" 54 #include "runtime/perfMemory.hpp" 55 #include "runtime/sharedRuntime.hpp" 56 #include "runtime/statSampler.hpp" 57 #include "runtime/stubRoutines.hpp" 58 #include "runtime/thread.inline.hpp" 59 #include "runtime/threadCritical.hpp" 60 #include "runtime/timer.hpp" 61 #include "semaphore_bsd.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 <sys/types.h> 74 # include <sys/mman.h> 75 # include <sys/stat.h> 76 # include <sys/select.h> 77 # include <pthread.h> 78 # include <signal.h> 79 # include <errno.h> 80 # include <dlfcn.h> 81 # include <stdio.h> 82 # include <unistd.h> 83 # include <sys/resource.h> 84 # include <pthread.h> 85 # include <sys/stat.h> 86 # include <sys/time.h> 87 # include <sys/times.h> 88 # include <sys/utsname.h> 89 # include <sys/socket.h> 90 # include <sys/wait.h> 91 # include <time.h> 92 # include <pwd.h> 93 # include <poll.h> 94 # include <semaphore.h> 95 # include <fcntl.h> 96 # include <string.h> 97 # include <sys/param.h> 98 # include <sys/sysctl.h> 99 # include <sys/ipc.h> 100 # include <sys/shm.h> 101 #ifndef __APPLE__ 102 # include <link.h> 103 #endif 104 # include <stdint.h> 105 # include <inttypes.h> 106 # include <sys/ioctl.h> 107 # include <sys/syscall.h> 108 109 #if defined(__FreeBSD__) || defined(__NetBSD__) 110 #include <elf.h> 111 #endif 112 113 #ifdef __APPLE__ 114 #include <mach/mach.h> // semaphore_* API 115 #include <mach-o/dyld.h> 116 #include <sys/proc_info.h> 117 #include <objc/objc-auto.h> 118 #endif 119 120 #ifndef MAP_ANONYMOUS 121 #define MAP_ANONYMOUS MAP_ANON 122 #endif 123 124 #define MAX_PATH (2 * K) 125 126 // for timer info max values which include all bits 127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 128 129 #define LARGEPAGES_BIT (1 << 6) 130 131 //////////////////////////////////////////////////////////////////////////////// 132 // global variables 133 julong os::Bsd::_physical_memory = 0; 134 135 #ifdef __APPLE__ 136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 137 volatile uint64_t os::Bsd::_max_abstime = 0; 138 #else 139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 140 #endif 141 pthread_t os::Bsd::_main_thread; 142 int os::Bsd::_page_size = -1; 143 144 static jlong initial_time_count=0; 145 146 static int clock_tics_per_sec = 100; 147 148 // For diagnostics to print a message once. see run_periodic_checks 149 static sigset_t check_signal_done; 150 static bool check_signals = true; 151 152 static pid_t _initial_pid = 0; 153 154 // Signal number used to suspend/resume a thread 155 156 // do not use any signal number less than SIGSEGV, see 4355769 157 static int SR_signum = SIGUSR2; 158 sigset_t SR_sigset; 159 160 161 //////////////////////////////////////////////////////////////////////////////// 162 // utility functions 163 164 static int SR_initialize(); 165 166 julong os::available_memory() { 167 return Bsd::available_memory(); 168 } 169 170 // available here means free 171 julong os::Bsd::available_memory() { 172 uint64_t available = physical_memory() >> 2; 173 #ifdef __APPLE__ 174 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 175 vm_statistics64_data_t vmstat; 176 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 177 (host_info64_t)&vmstat, &count); 178 assert(kerr == KERN_SUCCESS, 179 "host_statistics64 failed - check mach_host_self() and count"); 180 if (kerr == KERN_SUCCESS) { 181 available = vmstat.free_count * os::vm_page_size(); 182 } 183 #endif 184 return available; 185 } 186 187 julong os::physical_memory() { 188 return Bsd::physical_memory(); 189 } 190 191 // Return true if user is running as root. 192 193 bool os::have_special_privileges() { 194 static bool init = false; 195 static bool privileges = false; 196 if (!init) { 197 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 198 init = true; 199 } 200 return privileges; 201 } 202 203 204 205 // Cpu architecture string 206 #if defined(ZERO) 207 static char cpu_arch[] = ZERO_LIBARCH; 208 #elif defined(IA64) 209 static char cpu_arch[] = "ia64"; 210 #elif defined(IA32) 211 static char cpu_arch[] = "i386"; 212 #elif defined(AMD64) 213 static char cpu_arch[] = "amd64"; 214 #elif defined(ARM) 215 static char cpu_arch[] = "arm"; 216 #elif defined(PPC32) 217 static char cpu_arch[] = "ppc"; 218 #elif defined(SPARC) 219 #ifdef _LP64 220 static char cpu_arch[] = "sparcv9"; 221 #else 222 static char cpu_arch[] = "sparc"; 223 #endif 224 #else 225 #error Add appropriate cpu_arch setting 226 #endif 227 228 // Compiler variant 229 #ifdef COMPILER2 230 #define COMPILER_VARIANT "server" 231 #else 232 #define COMPILER_VARIANT "client" 233 #endif 234 235 236 void os::Bsd::initialize_system_info() { 237 int mib[2]; 238 size_t len; 239 int cpu_val; 240 julong mem_val; 241 242 // get processors count via hw.ncpus sysctl 243 mib[0] = CTL_HW; 244 mib[1] = HW_NCPU; 245 len = sizeof(cpu_val); 246 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 247 assert(len == sizeof(cpu_val), "unexpected data size"); 248 set_processor_count(cpu_val); 249 } else { 250 set_processor_count(1); // fallback 251 } 252 253 // get physical memory via hw.memsize sysctl (hw.memsize is used 254 // since it returns a 64 bit value) 255 mib[0] = CTL_HW; 256 257 #if defined (HW_MEMSIZE) // Apple 258 mib[1] = HW_MEMSIZE; 259 #elif defined(HW_PHYSMEM) // Most of BSD 260 mib[1] = HW_PHYSMEM; 261 #elif defined(HW_REALMEM) // Old FreeBSD 262 mib[1] = HW_REALMEM; 263 #else 264 #error No ways to get physmem 265 #endif 266 267 len = sizeof(mem_val); 268 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 269 assert(len == sizeof(mem_val), "unexpected data size"); 270 _physical_memory = mem_val; 271 } else { 272 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 273 } 274 275 #ifdef __OpenBSD__ 276 { 277 // limit _physical_memory memory view on OpenBSD since 278 // datasize rlimit restricts us anyway. 279 struct rlimit limits; 280 getrlimit(RLIMIT_DATA, &limits); 281 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 282 } 283 #endif 284 } 285 286 #ifdef __APPLE__ 287 static const char *get_home() { 288 const char *home_dir = ::getenv("HOME"); 289 if ((home_dir == NULL) || (*home_dir == '\0')) { 290 struct passwd *passwd_info = getpwuid(geteuid()); 291 if (passwd_info != NULL) { 292 home_dir = passwd_info->pw_dir; 293 } 294 } 295 296 return home_dir; 297 } 298 #endif 299 300 void os::init_system_properties_values() { 301 // The next steps are taken in the product version: 302 // 303 // Obtain the JAVA_HOME value from the location of libjvm.so. 304 // This library should be located at: 305 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 306 // 307 // If "/jre/lib/" appears at the right place in the path, then we 308 // assume libjvm.so is installed in a JDK and we use this path. 309 // 310 // Otherwise exit with message: "Could not create the Java virtual machine." 311 // 312 // The following extra steps are taken in the debugging version: 313 // 314 // If "/jre/lib/" does NOT appear at the right place in the path 315 // instead of exit check for $JAVA_HOME environment variable. 316 // 317 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 318 // then we append a fake suffix "hotspot/libjvm.so" to this path so 319 // it looks like libjvm.so is installed there 320 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 321 // 322 // Otherwise exit. 323 // 324 // Important note: if the location of libjvm.so changes this 325 // code needs to be changed accordingly. 326 327 // See ld(1): 328 // The linker uses the following search paths to locate required 329 // shared libraries: 330 // 1: ... 331 // ... 332 // 7: The default directories, normally /lib and /usr/lib. 333 #ifndef DEFAULT_LIBPATH 334 #define DEFAULT_LIBPATH "/lib:/usr/lib" 335 #endif 336 337 // Base path of extensions installed on the system. 338 #define SYS_EXT_DIR "/usr/java/packages" 339 #define EXTENSIONS_DIR "/lib/ext" 340 341 #ifndef __APPLE__ 342 343 // Buffer that fits several sprintfs. 344 // Note that the space for the colon and the trailing null are provided 345 // by the nulls included by the sizeof operator. 346 const size_t bufsize = 347 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 348 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 349 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 350 351 // sysclasspath, java_home, dll_dir 352 { 353 char *pslash; 354 os::jvm_path(buf, bufsize); 355 356 // Found the full path to libjvm.so. 357 // Now cut the path to <java_home>/jre if we can. 358 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 359 pslash = strrchr(buf, '/'); 360 if (pslash != NULL) { 361 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 362 } 363 Arguments::set_dll_dir(buf); 364 365 if (pslash != NULL) { 366 pslash = strrchr(buf, '/'); 367 if (pslash != NULL) { 368 *pslash = '\0'; // Get rid of /<arch>. 369 pslash = strrchr(buf, '/'); 370 if (pslash != NULL) { 371 *pslash = '\0'; // Get rid of /lib. 372 } 373 } 374 } 375 Arguments::set_java_home(buf); 376 set_boot_path('/', ':'); 377 } 378 379 // Where to look for native libraries. 380 // 381 // Note: Due to a legacy implementation, most of the library path 382 // is set in the launcher. This was to accomodate linking restrictions 383 // on legacy Bsd implementations (which are no longer supported). 384 // Eventually, all the library path setting will be done here. 385 // 386 // However, to prevent the proliferation of improperly built native 387 // libraries, the new path component /usr/java/packages is added here. 388 // Eventually, all the library path setting will be done here. 389 { 390 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 391 // should always exist (until the legacy problem cited above is 392 // addressed). 393 const char *v = ::getenv("LD_LIBRARY_PATH"); 394 const char *v_colon = ":"; 395 if (v == NULL) { v = ""; v_colon = ""; } 396 // That's +1 for the colon and +1 for the trailing '\0'. 397 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 398 strlen(v) + 1 + 399 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 400 mtInternal); 401 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 402 Arguments::set_library_path(ld_library_path); 403 FREE_C_HEAP_ARRAY(char, ld_library_path); 404 } 405 406 // Extensions directories. 407 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 408 Arguments::set_ext_dirs(buf); 409 410 FREE_C_HEAP_ARRAY(char, buf); 411 412 #else // __APPLE__ 413 414 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 415 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 416 417 const char *user_home_dir = get_home(); 418 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 419 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 420 sizeof(SYS_EXTENSIONS_DIRS); 421 422 // Buffer that fits several sprintfs. 423 // Note that the space for the colon and the trailing null are provided 424 // by the nulls included by the sizeof operator. 425 const size_t bufsize = 426 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 427 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 428 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 429 430 // sysclasspath, java_home, dll_dir 431 { 432 char *pslash; 433 os::jvm_path(buf, bufsize); 434 435 // Found the full path to libjvm.so. 436 // Now cut the path to <java_home>/jre if we can. 437 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 438 pslash = strrchr(buf, '/'); 439 if (pslash != NULL) { 440 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 441 } 442 #ifdef STATIC_BUILD 443 strcat(buf, "/lib"); 444 #endif 445 446 Arguments::set_dll_dir(buf); 447 448 if (pslash != NULL) { 449 pslash = strrchr(buf, '/'); 450 if (pslash != NULL) { 451 *pslash = '\0'; // Get rid of /lib. 452 } 453 } 454 Arguments::set_java_home(buf); 455 set_boot_path('/', ':'); 456 } 457 458 // Where to look for native libraries. 459 // 460 // Note: Due to a legacy implementation, most of the library path 461 // is set in the launcher. This was to accomodate linking restrictions 462 // on legacy Bsd implementations (which are no longer supported). 463 // Eventually, all the library path setting will be done here. 464 // 465 // However, to prevent the proliferation of improperly built native 466 // libraries, the new path component /usr/java/packages is added here. 467 // Eventually, all the library path setting will be done here. 468 { 469 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 470 // should always exist (until the legacy problem cited above is 471 // addressed). 472 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 473 // can specify a directory inside an app wrapper 474 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 475 const char *l_colon = ":"; 476 if (l == NULL) { l = ""; l_colon = ""; } 477 478 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 479 const char *v_colon = ":"; 480 if (v == NULL) { v = ""; v_colon = ""; } 481 482 // Apple's Java6 has "." at the beginning of java.library.path. 483 // OpenJDK on Windows has "." at the end of java.library.path. 484 // OpenJDK on Linux and Solaris don't have "." in java.library.path 485 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 486 // "." is appended to the end of java.library.path. Yes, this 487 // could cause a change in behavior, but Apple's Java6 behavior 488 // can be achieved by putting "." at the beginning of the 489 // JAVA_LIBRARY_PATH environment variable. 490 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 491 strlen(v) + 1 + strlen(l) + 1 + 492 system_ext_size + 3, 493 mtInternal); 494 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 495 v, v_colon, l, l_colon, user_home_dir); 496 Arguments::set_library_path(ld_library_path); 497 FREE_C_HEAP_ARRAY(char, ld_library_path); 498 } 499 500 // Extensions directories. 501 // 502 // Note that the space for the colon and the trailing null are provided 503 // by the nulls included by the sizeof operator (so actually one byte more 504 // than necessary is allocated). 505 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 506 user_home_dir, Arguments::get_java_home()); 507 Arguments::set_ext_dirs(buf); 508 509 FREE_C_HEAP_ARRAY(char, buf); 510 511 #undef SYS_EXTENSIONS_DIR 512 #undef SYS_EXTENSIONS_DIRS 513 514 #endif // __APPLE__ 515 516 #undef SYS_EXT_DIR 517 #undef EXTENSIONS_DIR 518 } 519 520 //////////////////////////////////////////////////////////////////////////////// 521 // breakpoint support 522 523 void os::breakpoint() { 524 BREAKPOINT; 525 } 526 527 extern "C" void breakpoint() { 528 // use debugger to set breakpoint here 529 } 530 531 //////////////////////////////////////////////////////////////////////////////// 532 // signal support 533 534 debug_only(static bool signal_sets_initialized = false); 535 static sigset_t unblocked_sigs, vm_sigs; 536 537 bool os::Bsd::is_sig_ignored(int sig) { 538 struct sigaction oact; 539 sigaction(sig, (struct sigaction*)NULL, &oact); 540 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 541 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 542 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) { 543 return true; 544 } else { 545 return false; 546 } 547 } 548 549 void os::Bsd::signal_sets_init() { 550 // Should also have an assertion stating we are still single-threaded. 551 assert(!signal_sets_initialized, "Already initialized"); 552 // Fill in signals that are necessarily unblocked for all threads in 553 // the VM. Currently, we unblock the following signals: 554 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 555 // by -Xrs (=ReduceSignalUsage)); 556 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 557 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 558 // the dispositions or masks wrt these signals. 559 // Programs embedding the VM that want to use the above signals for their 560 // own purposes must, at this time, use the "-Xrs" option to prevent 561 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 562 // (See bug 4345157, and other related bugs). 563 // In reality, though, unblocking these signals is really a nop, since 564 // these signals are not blocked by default. 565 sigemptyset(&unblocked_sigs); 566 sigaddset(&unblocked_sigs, SIGILL); 567 sigaddset(&unblocked_sigs, SIGSEGV); 568 sigaddset(&unblocked_sigs, SIGBUS); 569 sigaddset(&unblocked_sigs, SIGFPE); 570 sigaddset(&unblocked_sigs, SR_signum); 571 572 if (!ReduceSignalUsage) { 573 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 574 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 575 576 } 577 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 578 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 579 } 580 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 581 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 582 } 583 } 584 // Fill in signals that are blocked by all but the VM thread. 585 sigemptyset(&vm_sigs); 586 if (!ReduceSignalUsage) { 587 sigaddset(&vm_sigs, BREAK_SIGNAL); 588 } 589 debug_only(signal_sets_initialized = true); 590 591 } 592 593 // These are signals that are unblocked while a thread is running Java. 594 // (For some reason, they get blocked by default.) 595 sigset_t* os::Bsd::unblocked_signals() { 596 assert(signal_sets_initialized, "Not initialized"); 597 return &unblocked_sigs; 598 } 599 600 // These are the signals that are blocked while a (non-VM) thread is 601 // running Java. Only the VM thread handles these signals. 602 sigset_t* os::Bsd::vm_signals() { 603 assert(signal_sets_initialized, "Not initialized"); 604 return &vm_sigs; 605 } 606 607 void os::Bsd::hotspot_sigmask(Thread* thread) { 608 609 //Save caller's signal mask before setting VM signal mask 610 sigset_t caller_sigmask; 611 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 612 613 OSThread* osthread = thread->osthread(); 614 osthread->set_caller_sigmask(caller_sigmask); 615 616 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 617 618 if (!ReduceSignalUsage) { 619 if (thread->is_VM_thread()) { 620 // Only the VM thread handles BREAK_SIGNAL ... 621 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 622 } else { 623 // ... all other threads block BREAK_SIGNAL 624 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 625 } 626 } 627 } 628 629 630 ////////////////////////////////////////////////////////////////////////////// 631 // create new thread 632 633 #ifdef __APPLE__ 634 // library handle for calling objc_registerThreadWithCollector() 635 // without static linking to the libobjc library 636 #define OBJC_LIB "/usr/lib/libobjc.dylib" 637 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 638 typedef void (*objc_registerThreadWithCollector_t)(); 639 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 640 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 641 #endif 642 643 #ifdef __APPLE__ 644 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 645 // Additional thread_id used to correlate threads in SA 646 thread_identifier_info_data_t m_ident_info; 647 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 648 649 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 650 (thread_info_t) &m_ident_info, &count); 651 652 return m_ident_info.thread_id; 653 } 654 #endif 655 656 // Thread start routine for all newly created threads 657 static void *thread_native_entry(Thread *thread) { 658 // Try to randomize the cache line index of hot stack frames. 659 // This helps when threads of the same stack traces evict each other's 660 // cache lines. The threads can be either from the same JVM instance, or 661 // from different JVM instances. The benefit is especially true for 662 // processors with hyperthreading technology. 663 static int counter = 0; 664 int pid = os::current_process_id(); 665 alloca(((pid ^ counter++) & 7) * 128); 666 667 thread->initialize_thread_current(); 668 669 OSThread* osthread = thread->osthread(); 670 Monitor* sync = osthread->startThread_lock(); 671 672 osthread->set_thread_id(os::Bsd::gettid()); 673 674 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 675 os::current_thread_id(), (uintx) pthread_self()); 676 677 #ifdef __APPLE__ 678 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 679 guarantee(unique_thread_id != 0, "unique thread id was not found"); 680 osthread->set_unique_thread_id(unique_thread_id); 681 #endif 682 // initialize signal mask for this thread 683 os::Bsd::hotspot_sigmask(thread); 684 685 // initialize floating point control register 686 os::Bsd::init_thread_fpu_state(); 687 688 #ifdef __APPLE__ 689 // register thread with objc gc 690 if (objc_registerThreadWithCollectorFunction != NULL) { 691 objc_registerThreadWithCollectorFunction(); 692 } 693 #endif 694 695 // handshaking with parent thread 696 { 697 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 698 699 // notify parent thread 700 osthread->set_state(INITIALIZED); 701 sync->notify_all(); 702 703 // wait until os::start_thread() 704 while (osthread->get_state() == INITIALIZED) { 705 sync->wait(Mutex::_no_safepoint_check_flag); 706 } 707 } 708 709 // call one more level start routine 710 thread->run(); 711 712 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 713 os::current_thread_id(), (uintx) pthread_self()); 714 715 // If a thread has not deleted itself ("delete this") as part of its 716 // termination sequence, we have to ensure thread-local-storage is 717 // cleared before we actually terminate. No threads should ever be 718 // deleted asynchronously with respect to their termination. 719 if (Thread::current_or_null_safe() != NULL) { 720 assert(Thread::current_or_null_safe() == thread, "current thread is wrong"); 721 thread->clear_thread_current(); 722 } 723 724 return 0; 725 } 726 727 bool os::create_thread(Thread* thread, ThreadType thr_type, 728 size_t req_stack_size) { 729 assert(thread->osthread() == NULL, "caller responsible"); 730 731 // Allocate the OSThread object 732 OSThread* osthread = new OSThread(NULL, NULL); 733 if (osthread == NULL) { 734 return false; 735 } 736 737 // set the correct thread state 738 osthread->set_thread_type(thr_type); 739 740 // Initial state is ALLOCATED but not INITIALIZED 741 osthread->set_state(ALLOCATED); 742 743 thread->set_osthread(osthread); 744 745 // init thread attributes 746 pthread_attr_t attr; 747 pthread_attr_init(&attr); 748 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 749 750 // calculate stack size if it's not specified by caller 751 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size); 752 int status = pthread_attr_setstacksize(&attr, stack_size); 753 assert_status(status == 0, status, "pthread_attr_setstacksize"); 754 755 ThreadState state; 756 757 { 758 pthread_t tid; 759 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread); 760 761 char buf[64]; 762 if (ret == 0) { 763 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ", 764 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr)); 765 } else { 766 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.", 767 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr)); 768 } 769 770 pthread_attr_destroy(&attr); 771 772 if (ret != 0) { 773 // Need to clean up stuff we've allocated so far 774 thread->set_osthread(NULL); 775 delete osthread; 776 return false; 777 } 778 779 // Store pthread info into the OSThread 780 osthread->set_pthread_id(tid); 781 782 // Wait until child thread is either initialized or aborted 783 { 784 Monitor* sync_with_child = osthread->startThread_lock(); 785 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 786 while ((state = osthread->get_state()) == ALLOCATED) { 787 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 788 } 789 } 790 791 } 792 793 // Aborted due to thread limit being reached 794 if (state == ZOMBIE) { 795 thread->set_osthread(NULL); 796 delete osthread; 797 return false; 798 } 799 800 // The thread is returned suspended (in state INITIALIZED), 801 // and is started higher up in the call chain 802 assert(state == INITIALIZED, "race condition"); 803 return true; 804 } 805 806 ///////////////////////////////////////////////////////////////////////////// 807 // attach existing thread 808 809 // bootstrap the main thread 810 bool os::create_main_thread(JavaThread* thread) { 811 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 812 return create_attached_thread(thread); 813 } 814 815 bool os::create_attached_thread(JavaThread* thread) { 816 #ifdef ASSERT 817 thread->verify_not_published(); 818 #endif 819 820 // Allocate the OSThread object 821 OSThread* osthread = new OSThread(NULL, NULL); 822 823 if (osthread == NULL) { 824 return false; 825 } 826 827 osthread->set_thread_id(os::Bsd::gettid()); 828 829 // Store pthread info into the OSThread 830 #ifdef __APPLE__ 831 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 832 guarantee(unique_thread_id != 0, "just checking"); 833 osthread->set_unique_thread_id(unique_thread_id); 834 #endif 835 osthread->set_pthread_id(::pthread_self()); 836 837 // initialize floating point control register 838 os::Bsd::init_thread_fpu_state(); 839 840 // Initial thread state is RUNNABLE 841 osthread->set_state(RUNNABLE); 842 843 thread->set_osthread(osthread); 844 845 // initialize signal mask for this thread 846 // and save the caller's signal mask 847 os::Bsd::hotspot_sigmask(thread); 848 849 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 850 os::current_thread_id(), (uintx) pthread_self()); 851 852 return true; 853 } 854 855 void os::pd_start_thread(Thread* thread) { 856 OSThread * osthread = thread->osthread(); 857 assert(osthread->get_state() != INITIALIZED, "just checking"); 858 Monitor* sync_with_child = osthread->startThread_lock(); 859 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 860 sync_with_child->notify(); 861 } 862 863 // Free Bsd resources related to the OSThread 864 void os::free_thread(OSThread* osthread) { 865 assert(osthread != NULL, "osthread not set"); 866 867 // We are told to free resources of the argument thread, 868 // but we can only really operate on the current thread. 869 assert(Thread::current()->osthread() == osthread, 870 "os::free_thread but not current thread"); 871 872 // Restore caller's signal mask 873 sigset_t sigmask = osthread->caller_sigmask(); 874 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 875 876 delete osthread; 877 } 878 879 //////////////////////////////////////////////////////////////////////////////// 880 // time support 881 882 // Time since start-up in seconds to a fine granularity. 883 // Used by VMSelfDestructTimer and the MemProfiler. 884 double os::elapsedTime() { 885 886 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 887 } 888 889 jlong os::elapsed_counter() { 890 return javaTimeNanos() - initial_time_count; 891 } 892 893 jlong os::elapsed_frequency() { 894 return NANOSECS_PER_SEC; // nanosecond resolution 895 } 896 897 bool os::supports_vtime() { return true; } 898 bool os::enable_vtime() { return false; } 899 bool os::vtime_enabled() { return false; } 900 901 double os::elapsedVTime() { 902 // better than nothing, but not much 903 return elapsedTime(); 904 } 905 906 jlong os::javaTimeMillis() { 907 timeval time; 908 int status = gettimeofday(&time, NULL); 909 assert(status != -1, "bsd error"); 910 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 911 } 912 913 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 914 timeval time; 915 int status = gettimeofday(&time, NULL); 916 assert(status != -1, "bsd error"); 917 seconds = jlong(time.tv_sec); 918 nanos = jlong(time.tv_usec) * 1000; 919 } 920 921 #ifndef __APPLE__ 922 #ifndef CLOCK_MONOTONIC 923 #define CLOCK_MONOTONIC (1) 924 #endif 925 #endif 926 927 #ifdef __APPLE__ 928 void os::Bsd::clock_init() { 929 mach_timebase_info(&_timebase_info); 930 } 931 #else 932 void os::Bsd::clock_init() { 933 struct timespec res; 934 struct timespec tp; 935 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 936 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 937 // yes, monotonic clock is supported 938 _clock_gettime = ::clock_gettime; 939 } 940 } 941 #endif 942 943 944 945 #ifdef __APPLE__ 946 947 jlong os::javaTimeNanos() { 948 const uint64_t tm = mach_absolute_time(); 949 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 950 const uint64_t prev = Bsd::_max_abstime; 951 if (now <= prev) { 952 return prev; // same or retrograde time; 953 } 954 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev); 955 assert(obsv >= prev, "invariant"); // Monotonicity 956 // If the CAS succeeded then we're done and return "now". 957 // If the CAS failed and the observed value "obsv" is >= now then 958 // we should return "obsv". If the CAS failed and now > obsv > prv then 959 // some other thread raced this thread and installed a new value, in which case 960 // we could either (a) retry the entire operation, (b) retry trying to install now 961 // or (c) just return obsv. We use (c). No loop is required although in some cases 962 // we might discard a higher "now" value in deference to a slightly lower but freshly 963 // installed obsv value. That's entirely benign -- it admits no new orderings compared 964 // to (a) or (b) -- and greatly reduces coherence traffic. 965 // We might also condition (c) on the magnitude of the delta between obsv and now. 966 // Avoiding excessive CAS operations to hot RW locations is critical. 967 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 968 return (prev == obsv) ? now : obsv; 969 } 970 971 #else // __APPLE__ 972 973 jlong os::javaTimeNanos() { 974 if (os::supports_monotonic_clock()) { 975 struct timespec tp; 976 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 977 assert(status == 0, "gettime error"); 978 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 979 return result; 980 } else { 981 timeval time; 982 int status = gettimeofday(&time, NULL); 983 assert(status != -1, "bsd error"); 984 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 985 return 1000 * usecs; 986 } 987 } 988 989 #endif // __APPLE__ 990 991 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 992 if (os::supports_monotonic_clock()) { 993 info_ptr->max_value = ALL_64_BITS; 994 995 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 996 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 997 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 998 } else { 999 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1000 info_ptr->max_value = ALL_64_BITS; 1001 1002 // gettimeofday is a real time clock so it skips 1003 info_ptr->may_skip_backward = true; 1004 info_ptr->may_skip_forward = true; 1005 } 1006 1007 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1008 } 1009 1010 // Return the real, user, and system times in seconds from an 1011 // arbitrary fixed point in the past. 1012 bool os::getTimesSecs(double* process_real_time, 1013 double* process_user_time, 1014 double* process_system_time) { 1015 struct tms ticks; 1016 clock_t real_ticks = times(&ticks); 1017 1018 if (real_ticks == (clock_t) (-1)) { 1019 return false; 1020 } else { 1021 double ticks_per_second = (double) clock_tics_per_sec; 1022 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1023 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1024 *process_real_time = ((double) real_ticks) / ticks_per_second; 1025 1026 return true; 1027 } 1028 } 1029 1030 1031 char * os::local_time_string(char *buf, size_t buflen) { 1032 struct tm t; 1033 time_t long_time; 1034 time(&long_time); 1035 localtime_r(&long_time, &t); 1036 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1037 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1038 t.tm_hour, t.tm_min, t.tm_sec); 1039 return buf; 1040 } 1041 1042 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1043 return localtime_r(clock, res); 1044 } 1045 1046 //////////////////////////////////////////////////////////////////////////////// 1047 // runtime exit support 1048 1049 // Note: os::shutdown() might be called very early during initialization, or 1050 // called from signal handler. Before adding something to os::shutdown(), make 1051 // sure it is async-safe and can handle partially initialized VM. 1052 void os::shutdown() { 1053 1054 // allow PerfMemory to attempt cleanup of any persistent resources 1055 perfMemory_exit(); 1056 1057 // needs to remove object in file system 1058 AttachListener::abort(); 1059 1060 // flush buffered output, finish log files 1061 ostream_abort(); 1062 1063 // Check for abort hook 1064 abort_hook_t abort_hook = Arguments::abort_hook(); 1065 if (abort_hook != NULL) { 1066 abort_hook(); 1067 } 1068 1069 } 1070 1071 // Note: os::abort() might be called very early during initialization, or 1072 // called from signal handler. Before adding something to os::abort(), make 1073 // sure it is async-safe and can handle partially initialized VM. 1074 void os::abort(bool dump_core, void* siginfo, const void* context) { 1075 os::shutdown(); 1076 if (dump_core) { 1077 #ifndef PRODUCT 1078 fdStream out(defaultStream::output_fd()); 1079 out.print_raw("Current thread is "); 1080 char buf[16]; 1081 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1082 out.print_raw_cr(buf); 1083 out.print_raw_cr("Dumping core ..."); 1084 #endif 1085 ::abort(); // dump core 1086 } 1087 1088 ::exit(1); 1089 } 1090 1091 // Die immediately, no exit hook, no abort hook, no cleanup. 1092 void os::die() { 1093 // _exit() on BsdThreads only kills current thread 1094 ::abort(); 1095 } 1096 1097 // This method is a copy of JDK's sysGetLastErrorString 1098 // from src/solaris/hpi/src/system_md.c 1099 1100 size_t os::lasterror(char *buf, size_t len) { 1101 if (errno == 0) return 0; 1102 1103 const char *s = os::strerror(errno); 1104 size_t n = ::strlen(s); 1105 if (n >= len) { 1106 n = len - 1; 1107 } 1108 ::strncpy(buf, s, n); 1109 buf[n] = '\0'; 1110 return n; 1111 } 1112 1113 // Information of current thread in variety of formats 1114 pid_t os::Bsd::gettid() { 1115 int retval = -1; 1116 1117 #ifdef __APPLE__ //XNU kernel 1118 // despite the fact mach port is actually not a thread id use it 1119 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1120 retval = ::pthread_mach_thread_np(::pthread_self()); 1121 guarantee(retval != 0, "just checking"); 1122 return retval; 1123 1124 #else 1125 #ifdef __FreeBSD__ 1126 retval = syscall(SYS_thr_self); 1127 #else 1128 #ifdef __OpenBSD__ 1129 retval = syscall(SYS_getthrid); 1130 #else 1131 #ifdef __NetBSD__ 1132 retval = (pid_t) syscall(SYS__lwp_self); 1133 #endif 1134 #endif 1135 #endif 1136 #endif 1137 1138 if (retval == -1) { 1139 return getpid(); 1140 } 1141 } 1142 1143 intx os::current_thread_id() { 1144 #ifdef __APPLE__ 1145 return (intx)::pthread_mach_thread_np(::pthread_self()); 1146 #else 1147 return (intx)::pthread_self(); 1148 #endif 1149 } 1150 1151 int os::current_process_id() { 1152 1153 // Under the old bsd thread library, bsd gives each thread 1154 // its own process id. Because of this each thread will return 1155 // a different pid if this method were to return the result 1156 // of getpid(2). Bsd provides no api that returns the pid 1157 // of the launcher thread for the vm. This implementation 1158 // returns a unique pid, the pid of the launcher thread 1159 // that starts the vm 'process'. 1160 1161 // Under the NPTL, getpid() returns the same pid as the 1162 // launcher thread rather than a unique pid per thread. 1163 // Use gettid() if you want the old pre NPTL behaviour. 1164 1165 // if you are looking for the result of a call to getpid() that 1166 // returns a unique pid for the calling thread, then look at the 1167 // OSThread::thread_id() method in osThread_bsd.hpp file 1168 1169 return (int)(_initial_pid ? _initial_pid : getpid()); 1170 } 1171 1172 // DLL functions 1173 1174 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1175 1176 // This must be hard coded because it's the system's temporary 1177 // directory not the java application's temp directory, ala java.io.tmpdir. 1178 #ifdef __APPLE__ 1179 // macosx has a secure per-user temporary directory 1180 char temp_path_storage[PATH_MAX]; 1181 const char* os::get_temp_directory() { 1182 static char *temp_path = NULL; 1183 if (temp_path == NULL) { 1184 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1185 if (pathSize == 0 || pathSize > PATH_MAX) { 1186 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1187 } 1188 temp_path = temp_path_storage; 1189 } 1190 return temp_path; 1191 } 1192 #else // __APPLE__ 1193 const char* os::get_temp_directory() { return "/tmp"; } 1194 #endif // __APPLE__ 1195 1196 // check if addr is inside libjvm.so 1197 bool os::address_is_in_vm(address addr) { 1198 static address libjvm_base_addr; 1199 Dl_info dlinfo; 1200 1201 if (libjvm_base_addr == NULL) { 1202 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1203 libjvm_base_addr = (address)dlinfo.dli_fbase; 1204 } 1205 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1206 } 1207 1208 if (dladdr((void *)addr, &dlinfo) != 0) { 1209 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1210 } 1211 1212 return false; 1213 } 1214 1215 1216 #define MACH_MAXSYMLEN 256 1217 1218 bool os::dll_address_to_function_name(address addr, char *buf, 1219 int buflen, int *offset, 1220 bool demangle) { 1221 // buf is not optional, but offset is optional 1222 assert(buf != NULL, "sanity check"); 1223 1224 Dl_info dlinfo; 1225 char localbuf[MACH_MAXSYMLEN]; 1226 1227 if (dladdr((void*)addr, &dlinfo) != 0) { 1228 // see if we have a matching symbol 1229 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1230 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) { 1231 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1232 } 1233 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1234 return true; 1235 } 1236 // no matching symbol so try for just file info 1237 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1238 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1239 buf, buflen, offset, dlinfo.dli_fname, demangle)) { 1240 return true; 1241 } 1242 } 1243 1244 // Handle non-dynamic manually: 1245 if (dlinfo.dli_fbase != NULL && 1246 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1247 dlinfo.dli_fbase)) { 1248 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) { 1249 jio_snprintf(buf, buflen, "%s", localbuf); 1250 } 1251 return true; 1252 } 1253 } 1254 buf[0] = '\0'; 1255 if (offset != NULL) *offset = -1; 1256 return false; 1257 } 1258 1259 // ported from solaris version 1260 bool os::dll_address_to_library_name(address addr, char* buf, 1261 int buflen, int* offset) { 1262 // buf is not optional, but offset is optional 1263 assert(buf != NULL, "sanity check"); 1264 1265 Dl_info dlinfo; 1266 1267 if (dladdr((void*)addr, &dlinfo) != 0) { 1268 if (dlinfo.dli_fname != NULL) { 1269 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1270 } 1271 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1272 *offset = addr - (address)dlinfo.dli_fbase; 1273 } 1274 return true; 1275 } 1276 1277 buf[0] = '\0'; 1278 if (offset) *offset = -1; 1279 return false; 1280 } 1281 1282 // Loads .dll/.so and 1283 // in case of error it checks if .dll/.so was built for the 1284 // same architecture as Hotspot is running on 1285 1286 #ifdef __APPLE__ 1287 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1288 #ifdef STATIC_BUILD 1289 return os::get_default_process_handle(); 1290 #else 1291 void * result= ::dlopen(filename, RTLD_LAZY); 1292 if (result != NULL) { 1293 // Successful loading 1294 return result; 1295 } 1296 1297 // Read system error message into ebuf 1298 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1299 ebuf[ebuflen-1]='\0'; 1300 1301 return NULL; 1302 #endif // STATIC_BUILD 1303 } 1304 #else 1305 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1306 #ifdef STATIC_BUILD 1307 return os::get_default_process_handle(); 1308 #else 1309 void * result= ::dlopen(filename, RTLD_LAZY); 1310 if (result != NULL) { 1311 // Successful loading 1312 return result; 1313 } 1314 1315 Elf32_Ehdr elf_head; 1316 1317 // Read system error message into ebuf 1318 // It may or may not be overwritten below 1319 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1320 ebuf[ebuflen-1]='\0'; 1321 int diag_msg_max_length=ebuflen-strlen(ebuf); 1322 char* diag_msg_buf=ebuf+strlen(ebuf); 1323 1324 if (diag_msg_max_length==0) { 1325 // No more space in ebuf for additional diagnostics message 1326 return NULL; 1327 } 1328 1329 1330 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1331 1332 if (file_descriptor < 0) { 1333 // Can't open library, report dlerror() message 1334 return NULL; 1335 } 1336 1337 bool failed_to_read_elf_head= 1338 (sizeof(elf_head)!= 1339 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1340 1341 ::close(file_descriptor); 1342 if (failed_to_read_elf_head) { 1343 // file i/o error - report dlerror() msg 1344 return NULL; 1345 } 1346 1347 typedef struct { 1348 Elf32_Half code; // Actual value as defined in elf.h 1349 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1350 char elf_class; // 32 or 64 bit 1351 char endianess; // MSB or LSB 1352 char* name; // String representation 1353 } arch_t; 1354 1355 #ifndef EM_486 1356 #define EM_486 6 /* Intel 80486 */ 1357 #endif 1358 1359 #ifndef EM_MIPS_RS3_LE 1360 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1361 #endif 1362 1363 #ifndef EM_PPC64 1364 #define EM_PPC64 21 /* PowerPC64 */ 1365 #endif 1366 1367 #ifndef EM_S390 1368 #define EM_S390 22 /* IBM System/390 */ 1369 #endif 1370 1371 #ifndef EM_IA_64 1372 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1373 #endif 1374 1375 #ifndef EM_X86_64 1376 #define EM_X86_64 62 /* AMD x86-64 */ 1377 #endif 1378 1379 static const arch_t arch_array[]={ 1380 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1381 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1382 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1383 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1384 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1385 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1386 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1387 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1388 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1389 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1390 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1391 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1392 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1393 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1394 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1395 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1396 }; 1397 1398 #if (defined IA32) 1399 static Elf32_Half running_arch_code=EM_386; 1400 #elif (defined AMD64) 1401 static Elf32_Half running_arch_code=EM_X86_64; 1402 #elif (defined IA64) 1403 static Elf32_Half running_arch_code=EM_IA_64; 1404 #elif (defined __sparc) && (defined _LP64) 1405 static Elf32_Half running_arch_code=EM_SPARCV9; 1406 #elif (defined __sparc) && (!defined _LP64) 1407 static Elf32_Half running_arch_code=EM_SPARC; 1408 #elif (defined __powerpc64__) 1409 static Elf32_Half running_arch_code=EM_PPC64; 1410 #elif (defined __powerpc__) 1411 static Elf32_Half running_arch_code=EM_PPC; 1412 #elif (defined ARM) 1413 static Elf32_Half running_arch_code=EM_ARM; 1414 #elif (defined S390) 1415 static Elf32_Half running_arch_code=EM_S390; 1416 #elif (defined ALPHA) 1417 static Elf32_Half running_arch_code=EM_ALPHA; 1418 #elif (defined MIPSEL) 1419 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1420 #elif (defined PARISC) 1421 static Elf32_Half running_arch_code=EM_PARISC; 1422 #elif (defined MIPS) 1423 static Elf32_Half running_arch_code=EM_MIPS; 1424 #elif (defined M68K) 1425 static Elf32_Half running_arch_code=EM_68K; 1426 #else 1427 #error Method os::dll_load requires that one of following is defined:\ 1428 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1429 #endif 1430 1431 // Identify compatability class for VM's architecture and library's architecture 1432 // Obtain string descriptions for architectures 1433 1434 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1435 int running_arch_index=-1; 1436 1437 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1438 if (running_arch_code == arch_array[i].code) { 1439 running_arch_index = i; 1440 } 1441 if (lib_arch.code == arch_array[i].code) { 1442 lib_arch.compat_class = arch_array[i].compat_class; 1443 lib_arch.name = arch_array[i].name; 1444 } 1445 } 1446 1447 assert(running_arch_index != -1, 1448 "Didn't find running architecture code (running_arch_code) in arch_array"); 1449 if (running_arch_index == -1) { 1450 // Even though running architecture detection failed 1451 // we may still continue with reporting dlerror() message 1452 return NULL; 1453 } 1454 1455 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1456 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1457 return NULL; 1458 } 1459 1460 #ifndef S390 1461 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1462 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1463 return NULL; 1464 } 1465 #endif // !S390 1466 1467 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1468 if (lib_arch.name!=NULL) { 1469 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1470 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1471 lib_arch.name, arch_array[running_arch_index].name); 1472 } else { 1473 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1474 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1475 lib_arch.code, 1476 arch_array[running_arch_index].name); 1477 } 1478 } 1479 1480 return NULL; 1481 #endif // STATIC_BUILD 1482 } 1483 #endif // !__APPLE__ 1484 1485 void* os::get_default_process_handle() { 1486 #ifdef __APPLE__ 1487 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1488 // to avoid finding unexpected symbols on second (or later) 1489 // loads of a library. 1490 return (void*)::dlopen(NULL, RTLD_FIRST); 1491 #else 1492 return (void*)::dlopen(NULL, RTLD_LAZY); 1493 #endif 1494 } 1495 1496 // XXX: Do we need a lock around this as per Linux? 1497 void* os::dll_lookup(void* handle, const char* name) { 1498 return dlsym(handle, name); 1499 } 1500 1501 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1502 outputStream * out = (outputStream *) param; 1503 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name); 1504 return 0; 1505 } 1506 1507 void os::print_dll_info(outputStream *st) { 1508 st->print_cr("Dynamic libraries:"); 1509 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1510 st->print_cr("Error: Cannot print dynamic libraries."); 1511 } 1512 } 1513 1514 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1515 #ifdef RTLD_DI_LINKMAP 1516 Dl_info dli; 1517 void *handle; 1518 Link_map *map; 1519 Link_map *p; 1520 1521 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1522 dli.dli_fname == NULL) { 1523 return 1; 1524 } 1525 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1526 if (handle == NULL) { 1527 return 1; 1528 } 1529 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1530 if (map == NULL) { 1531 dlclose(handle); 1532 return 1; 1533 } 1534 1535 while (map->l_prev != NULL) 1536 map = map->l_prev; 1537 1538 while (map != NULL) { 1539 // Value for top_address is returned as 0 since we don't have any information about module size 1540 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1541 dlclose(handle); 1542 return 1; 1543 } 1544 map = map->l_next; 1545 } 1546 1547 dlclose(handle); 1548 #elif defined(__APPLE__) 1549 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1550 // Value for top_address is returned as 0 since we don't have any information about module size 1551 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1552 return 1; 1553 } 1554 } 1555 return 0; 1556 #else 1557 return 1; 1558 #endif 1559 } 1560 1561 void os::get_summary_os_info(char* buf, size_t buflen) { 1562 // These buffers are small because we want this to be brief 1563 // and not use a lot of stack while generating the hs_err file. 1564 char os[100]; 1565 size_t size = sizeof(os); 1566 int mib_kern[] = { CTL_KERN, KERN_OSTYPE }; 1567 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) { 1568 #ifdef __APPLE__ 1569 strncpy(os, "Darwin", sizeof(os)); 1570 #elif __OpenBSD__ 1571 strncpy(os, "OpenBSD", sizeof(os)); 1572 #else 1573 strncpy(os, "BSD", sizeof(os)); 1574 #endif 1575 } 1576 1577 char release[100]; 1578 size = sizeof(release); 1579 int mib_release[] = { CTL_KERN, KERN_OSRELEASE }; 1580 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) { 1581 // if error, leave blank 1582 strncpy(release, "", sizeof(release)); 1583 } 1584 snprintf(buf, buflen, "%s %s", os, release); 1585 } 1586 1587 void os::print_os_info_brief(outputStream* st) { 1588 os::Posix::print_uname_info(st); 1589 } 1590 1591 void os::print_os_info(outputStream* st) { 1592 st->print("OS:"); 1593 1594 os::Posix::print_uname_info(st); 1595 1596 os::Posix::print_rlimit_info(st); 1597 1598 os::Posix::print_load_average(st); 1599 } 1600 1601 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) { 1602 // Nothing to do for now. 1603 } 1604 1605 void os::get_summary_cpu_info(char* buf, size_t buflen) { 1606 unsigned int mhz; 1607 size_t size = sizeof(mhz); 1608 int mib[] = { CTL_HW, HW_CPU_FREQ }; 1609 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) { 1610 mhz = 1; // looks like an error but can be divided by 1611 } else { 1612 mhz /= 1000000; // reported in millions 1613 } 1614 1615 char model[100]; 1616 size = sizeof(model); 1617 int mib_model[] = { CTL_HW, HW_MODEL }; 1618 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) { 1619 strncpy(model, cpu_arch, sizeof(model)); 1620 } 1621 1622 char machine[100]; 1623 size = sizeof(machine); 1624 int mib_machine[] = { CTL_HW, HW_MACHINE }; 1625 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) { 1626 strncpy(machine, "", sizeof(machine)); 1627 } 1628 1629 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz); 1630 } 1631 1632 void os::print_memory_info(outputStream* st) { 1633 1634 st->print("Memory:"); 1635 st->print(" %dk page", os::vm_page_size()>>10); 1636 1637 st->print(", physical " UINT64_FORMAT "k", 1638 os::physical_memory() >> 10); 1639 st->print("(" UINT64_FORMAT "k free)", 1640 os::available_memory() >> 10); 1641 st->cr(); 1642 } 1643 1644 static void print_signal_handler(outputStream* st, int sig, 1645 char* buf, size_t buflen); 1646 1647 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1648 st->print_cr("Signal Handlers:"); 1649 print_signal_handler(st, SIGSEGV, buf, buflen); 1650 print_signal_handler(st, SIGBUS , buf, buflen); 1651 print_signal_handler(st, SIGFPE , buf, buflen); 1652 print_signal_handler(st, SIGPIPE, buf, buflen); 1653 print_signal_handler(st, SIGXFSZ, buf, buflen); 1654 print_signal_handler(st, SIGILL , buf, buflen); 1655 print_signal_handler(st, SR_signum, buf, buflen); 1656 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1657 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1658 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1659 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1660 } 1661 1662 static char saved_jvm_path[MAXPATHLEN] = {0}; 1663 1664 // Find the full path to the current module, libjvm 1665 void os::jvm_path(char *buf, jint buflen) { 1666 // Error checking. 1667 if (buflen < MAXPATHLEN) { 1668 assert(false, "must use a large-enough buffer"); 1669 buf[0] = '\0'; 1670 return; 1671 } 1672 // Lazy resolve the path to current module. 1673 if (saved_jvm_path[0] != 0) { 1674 strcpy(buf, saved_jvm_path); 1675 return; 1676 } 1677 1678 char dli_fname[MAXPATHLEN]; 1679 bool ret = dll_address_to_library_name( 1680 CAST_FROM_FN_PTR(address, os::jvm_path), 1681 dli_fname, sizeof(dli_fname), NULL); 1682 assert(ret, "cannot locate libjvm"); 1683 char *rp = NULL; 1684 if (ret && dli_fname[0] != '\0') { 1685 rp = os::Posix::realpath(dli_fname, buf, buflen); 1686 } 1687 if (rp == NULL) { 1688 return; 1689 } 1690 1691 if (Arguments::sun_java_launcher_is_altjvm()) { 1692 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1693 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1694 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1695 // appears at the right place in the string, then assume we are 1696 // installed in a JDK and we're done. Otherwise, check for a 1697 // JAVA_HOME environment variable and construct a path to the JVM 1698 // being overridden. 1699 1700 const char *p = buf + strlen(buf) - 1; 1701 for (int count = 0; p > buf && count < 5; ++count) { 1702 for (--p; p > buf && *p != '/'; --p) 1703 /* empty */ ; 1704 } 1705 1706 if (strncmp(p, "/jre/lib/", 9) != 0) { 1707 // Look for JAVA_HOME in the environment. 1708 char* java_home_var = ::getenv("JAVA_HOME"); 1709 if (java_home_var != NULL && java_home_var[0] != 0) { 1710 char* jrelib_p; 1711 int len; 1712 1713 // Check the current module name "libjvm" 1714 p = strrchr(buf, '/'); 1715 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1716 1717 rp = os::Posix::realpath(java_home_var, buf, buflen); 1718 if (rp == NULL) { 1719 return; 1720 } 1721 1722 // determine if this is a legacy image or modules image 1723 // modules image doesn't have "jre" subdirectory 1724 len = strlen(buf); 1725 assert(len < buflen, "Ran out of buffer space"); 1726 jrelib_p = buf + len; 1727 1728 // Add the appropriate library subdir 1729 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1730 if (0 != access(buf, F_OK)) { 1731 snprintf(jrelib_p, buflen-len, "/lib"); 1732 } 1733 1734 // Add the appropriate client or server subdir 1735 len = strlen(buf); 1736 jrelib_p = buf + len; 1737 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1738 if (0 != access(buf, F_OK)) { 1739 snprintf(jrelib_p, buflen-len, "%s", ""); 1740 } 1741 1742 // If the path exists within JAVA_HOME, add the JVM library name 1743 // to complete the path to JVM being overridden. Otherwise fallback 1744 // to the path to the current library. 1745 if (0 == access(buf, F_OK)) { 1746 // Use current module name "libjvm" 1747 len = strlen(buf); 1748 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1749 } else { 1750 // Fall back to path of current library 1751 rp = os::Posix::realpath(dli_fname, buf, buflen); 1752 if (rp == NULL) { 1753 return; 1754 } 1755 } 1756 } 1757 } 1758 } 1759 1760 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1761 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1762 } 1763 1764 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1765 // no prefix required, not even "_" 1766 } 1767 1768 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1769 // no suffix required 1770 } 1771 1772 //////////////////////////////////////////////////////////////////////////////// 1773 // sun.misc.Signal support 1774 1775 static volatile jint sigint_count = 0; 1776 1777 static void UserHandler(int sig, void *siginfo, void *context) { 1778 // 4511530 - sem_post is serialized and handled by the manager thread. When 1779 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1780 // don't want to flood the manager thread with sem_post requests. 1781 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1782 return; 1783 } 1784 1785 // Ctrl-C is pressed during error reporting, likely because the error 1786 // handler fails to abort. Let VM die immediately. 1787 if (sig == SIGINT && VMError::is_error_reported()) { 1788 os::die(); 1789 } 1790 1791 os::signal_notify(sig); 1792 } 1793 1794 void* os::user_handler() { 1795 return CAST_FROM_FN_PTR(void*, UserHandler); 1796 } 1797 1798 extern "C" { 1799 typedef void (*sa_handler_t)(int); 1800 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1801 } 1802 1803 void* os::signal(int signal_number, void* handler) { 1804 struct sigaction sigAct, oldSigAct; 1805 1806 sigfillset(&(sigAct.sa_mask)); 1807 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1808 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1809 1810 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1811 // -1 means registration failed 1812 return (void *)-1; 1813 } 1814 1815 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1816 } 1817 1818 void os::signal_raise(int signal_number) { 1819 ::raise(signal_number); 1820 } 1821 1822 // The following code is moved from os.cpp for making this 1823 // code platform specific, which it is by its very nature. 1824 1825 // Will be modified when max signal is changed to be dynamic 1826 int os::sigexitnum_pd() { 1827 return NSIG; 1828 } 1829 1830 // a counter for each possible signal value 1831 static volatile jint pending_signals[NSIG+1] = { 0 }; 1832 1833 // Bsd(POSIX) specific hand shaking semaphore. 1834 #ifdef __APPLE__ 1835 typedef semaphore_t os_semaphore_t; 1836 1837 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1838 #define SEM_WAIT(sem) semaphore_wait(sem) 1839 #define SEM_POST(sem) semaphore_signal(sem) 1840 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1841 #else 1842 typedef sem_t os_semaphore_t; 1843 1844 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1845 #define SEM_WAIT(sem) sem_wait(&sem) 1846 #define SEM_POST(sem) sem_post(&sem) 1847 #define SEM_DESTROY(sem) sem_destroy(&sem) 1848 #endif 1849 1850 #ifdef __APPLE__ 1851 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used. 1852 1853 static const char* sem_init_strerror(kern_return_t value) { 1854 switch (value) { 1855 case KERN_INVALID_ARGUMENT: return "Invalid argument"; 1856 case KERN_RESOURCE_SHORTAGE: return "Resource shortage"; 1857 default: return "Unknown"; 1858 } 1859 } 1860 1861 OSXSemaphore::OSXSemaphore(uint value) { 1862 kern_return_t ret = SEM_INIT(_semaphore, value); 1863 1864 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret)); 1865 } 1866 1867 OSXSemaphore::~OSXSemaphore() { 1868 SEM_DESTROY(_semaphore); 1869 } 1870 1871 void OSXSemaphore::signal(uint count) { 1872 for (uint i = 0; i < count; i++) { 1873 kern_return_t ret = SEM_POST(_semaphore); 1874 1875 assert(ret == KERN_SUCCESS, "Failed to signal semaphore"); 1876 } 1877 } 1878 1879 void OSXSemaphore::wait() { 1880 kern_return_t ret; 1881 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) { 1882 // Semaphore was interrupted. Retry. 1883 } 1884 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore"); 1885 } 1886 1887 jlong OSXSemaphore::currenttime() { 1888 struct timeval tv; 1889 gettimeofday(&tv, NULL); 1890 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1891 } 1892 1893 bool OSXSemaphore::trywait() { 1894 return timedwait(0, 0); 1895 } 1896 1897 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) { 1898 kern_return_t kr = KERN_ABORTED; 1899 mach_timespec_t waitspec; 1900 waitspec.tv_sec = sec; 1901 waitspec.tv_nsec = nsec; 1902 1903 jlong starttime = currenttime(); 1904 1905 kr = semaphore_timedwait(_semaphore, waitspec); 1906 while (kr == KERN_ABORTED) { 1907 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1908 1909 jlong current = currenttime(); 1910 jlong passedtime = current - starttime; 1911 1912 if (passedtime >= totalwait) { 1913 waitspec.tv_sec = 0; 1914 waitspec.tv_nsec = 0; 1915 } else { 1916 jlong waittime = totalwait - (current - starttime); 1917 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 1918 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 1919 } 1920 1921 kr = semaphore_timedwait(_semaphore, waitspec); 1922 } 1923 1924 return kr == KERN_SUCCESS; 1925 } 1926 1927 #else 1928 // Use POSIX implementation of semaphores. 1929 1930 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) { 1931 struct timespec ts; 1932 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 1933 1934 return ts; 1935 } 1936 1937 #endif // __APPLE__ 1938 1939 static os_semaphore_t sig_sem; 1940 1941 #ifdef __APPLE__ 1942 static OSXSemaphore sr_semaphore; 1943 #else 1944 static PosixSemaphore sr_semaphore; 1945 #endif 1946 1947 void os::signal_init_pd() { 1948 // Initialize signal structures 1949 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 1950 1951 // Initialize signal semaphore 1952 ::SEM_INIT(sig_sem, 0); 1953 } 1954 1955 void os::signal_notify(int sig) { 1956 Atomic::inc(&pending_signals[sig]); 1957 ::SEM_POST(sig_sem); 1958 } 1959 1960 static int check_pending_signals(bool wait) { 1961 Atomic::store(0, &sigint_count); 1962 for (;;) { 1963 for (int i = 0; i < NSIG + 1; i++) { 1964 jint n = pending_signals[i]; 1965 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 1966 return i; 1967 } 1968 } 1969 if (!wait) { 1970 return -1; 1971 } 1972 JavaThread *thread = JavaThread::current(); 1973 ThreadBlockInVM tbivm(thread); 1974 1975 bool threadIsSuspended; 1976 do { 1977 thread->set_suspend_equivalent(); 1978 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 1979 ::SEM_WAIT(sig_sem); 1980 1981 // were we externally suspended while we were waiting? 1982 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 1983 if (threadIsSuspended) { 1984 // The semaphore has been incremented, but while we were waiting 1985 // another thread suspended us. We don't want to continue running 1986 // while suspended because that would surprise the thread that 1987 // suspended us. 1988 ::SEM_POST(sig_sem); 1989 1990 thread->java_suspend_self(); 1991 } 1992 } while (threadIsSuspended); 1993 } 1994 } 1995 1996 int os::signal_lookup() { 1997 return check_pending_signals(false); 1998 } 1999 2000 int os::signal_wait() { 2001 return check_pending_signals(true); 2002 } 2003 2004 //////////////////////////////////////////////////////////////////////////////// 2005 // Virtual Memory 2006 2007 int os::vm_page_size() { 2008 // Seems redundant as all get out 2009 assert(os::Bsd::page_size() != -1, "must call os::init"); 2010 return os::Bsd::page_size(); 2011 } 2012 2013 // Solaris allocates memory by pages. 2014 int os::vm_allocation_granularity() { 2015 assert(os::Bsd::page_size() != -1, "must call os::init"); 2016 return os::Bsd::page_size(); 2017 } 2018 2019 // Rationale behind this function: 2020 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2021 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2022 // samples for JITted code. Here we create private executable mapping over the code cache 2023 // and then we can use standard (well, almost, as mapping can change) way to provide 2024 // info for the reporting script by storing timestamp and location of symbol 2025 void bsd_wrap_code(char* base, size_t size) { 2026 static volatile jint cnt = 0; 2027 2028 if (!UseOprofile) { 2029 return; 2030 } 2031 2032 char buf[PATH_MAX + 1]; 2033 int num = Atomic::add(1, &cnt); 2034 2035 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2036 os::get_temp_directory(), os::current_process_id(), num); 2037 unlink(buf); 2038 2039 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2040 2041 if (fd != -1) { 2042 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2043 if (rv != (off_t)-1) { 2044 if (::write(fd, "", 1) == 1) { 2045 mmap(base, size, 2046 PROT_READ|PROT_WRITE|PROT_EXEC, 2047 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2048 } 2049 } 2050 ::close(fd); 2051 unlink(buf); 2052 } 2053 } 2054 2055 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2056 int err) { 2057 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT 2058 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec, 2059 os::errno_name(err), err); 2060 } 2061 2062 // NOTE: Bsd kernel does not really reserve the pages for us. 2063 // All it does is to check if there are enough free pages 2064 // left at the time of mmap(). This could be a potential 2065 // problem. 2066 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2067 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2068 #ifdef __OpenBSD__ 2069 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2070 if (::mprotect(addr, size, prot) == 0) { 2071 return true; 2072 } 2073 #else 2074 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2075 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2076 if (res != (uintptr_t) MAP_FAILED) { 2077 return true; 2078 } 2079 #endif 2080 2081 // Warn about any commit errors we see in non-product builds just 2082 // in case mmap() doesn't work as described on the man page. 2083 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2084 2085 return false; 2086 } 2087 2088 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2089 bool exec) { 2090 // alignment_hint is ignored on this OS 2091 return pd_commit_memory(addr, size, exec); 2092 } 2093 2094 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2095 const char* mesg) { 2096 assert(mesg != NULL, "mesg must be specified"); 2097 if (!pd_commit_memory(addr, size, exec)) { 2098 // add extra info in product mode for vm_exit_out_of_memory(): 2099 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2100 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg); 2101 } 2102 } 2103 2104 void os::pd_commit_memory_or_exit(char* addr, size_t size, 2105 size_t alignment_hint, bool exec, 2106 const char* mesg) { 2107 // alignment_hint is ignored on this OS 2108 pd_commit_memory_or_exit(addr, size, exec, mesg); 2109 } 2110 2111 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2112 } 2113 2114 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2115 ::madvise(addr, bytes, MADV_DONTNEED); 2116 } 2117 2118 void os::numa_make_global(char *addr, size_t bytes) { 2119 } 2120 2121 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2122 } 2123 2124 bool os::numa_topology_changed() { return false; } 2125 2126 size_t os::numa_get_groups_num() { 2127 return 1; 2128 } 2129 2130 int os::numa_get_group_id() { 2131 return 0; 2132 } 2133 2134 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2135 if (size > 0) { 2136 ids[0] = 0; 2137 return 1; 2138 } 2139 return 0; 2140 } 2141 2142 bool os::get_page_info(char *start, page_info* info) { 2143 return false; 2144 } 2145 2146 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2147 return end; 2148 } 2149 2150 2151 bool os::pd_uncommit_memory(char* addr, size_t size) { 2152 #ifdef __OpenBSD__ 2153 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2154 return ::mprotect(addr, size, PROT_NONE) == 0; 2155 #else 2156 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2157 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2158 return res != (uintptr_t) MAP_FAILED; 2159 #endif 2160 } 2161 2162 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2163 return os::commit_memory(addr, size, !ExecMem); 2164 } 2165 2166 // If this is a growable mapping, remove the guard pages entirely by 2167 // munmap()ping them. If not, just call uncommit_memory(). 2168 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2169 return os::uncommit_memory(addr, size); 2170 } 2171 2172 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2173 // at 'requested_addr'. If there are existing memory mappings at the same 2174 // location, however, they will be overwritten. If 'fixed' is false, 2175 // 'requested_addr' is only treated as a hint, the return value may or 2176 // may not start from the requested address. Unlike Bsd mmap(), this 2177 // function returns NULL to indicate failure. 2178 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2179 char * addr; 2180 int flags; 2181 2182 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2183 if (fixed) { 2184 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2185 flags |= MAP_FIXED; 2186 } 2187 2188 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2189 // touch an uncommitted page. Otherwise, the read/write might 2190 // succeed if we have enough swap space to back the physical page. 2191 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2192 flags, -1, 0); 2193 2194 return addr == MAP_FAILED ? NULL : addr; 2195 } 2196 2197 static int anon_munmap(char * addr, size_t size) { 2198 return ::munmap(addr, size) == 0; 2199 } 2200 2201 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2202 size_t alignment_hint) { 2203 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2204 } 2205 2206 bool os::pd_release_memory(char* addr, size_t size) { 2207 return anon_munmap(addr, size); 2208 } 2209 2210 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2211 // Bsd wants the mprotect address argument to be page aligned. 2212 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size()); 2213 2214 // According to SUSv3, mprotect() should only be used with mappings 2215 // established by mmap(), and mmap() always maps whole pages. Unaligned 2216 // 'addr' likely indicates problem in the VM (e.g. trying to change 2217 // protection of malloc'ed or statically allocated memory). Check the 2218 // caller if you hit this assert. 2219 assert(addr == bottom, "sanity check"); 2220 2221 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2222 return ::mprotect(bottom, size, prot) == 0; 2223 } 2224 2225 // Set protections specified 2226 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2227 bool is_committed) { 2228 unsigned int p = 0; 2229 switch (prot) { 2230 case MEM_PROT_NONE: p = PROT_NONE; break; 2231 case MEM_PROT_READ: p = PROT_READ; break; 2232 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2233 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2234 default: 2235 ShouldNotReachHere(); 2236 } 2237 // is_committed is unused. 2238 return bsd_mprotect(addr, bytes, p); 2239 } 2240 2241 bool os::guard_memory(char* addr, size_t size) { 2242 return bsd_mprotect(addr, size, PROT_NONE); 2243 } 2244 2245 bool os::unguard_memory(char* addr, size_t size) { 2246 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2247 } 2248 2249 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2250 return false; 2251 } 2252 2253 // Large page support 2254 2255 static size_t _large_page_size = 0; 2256 2257 void os::large_page_init() { 2258 } 2259 2260 2261 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2262 fatal("This code is not used or maintained."); 2263 2264 // "exec" is passed in but not used. Creating the shared image for 2265 // the code cache doesn't have an SHM_X executable permission to check. 2266 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2267 2268 key_t key = IPC_PRIVATE; 2269 char *addr; 2270 2271 bool warn_on_failure = UseLargePages && 2272 (!FLAG_IS_DEFAULT(UseLargePages) || 2273 !FLAG_IS_DEFAULT(LargePageSizeInBytes)); 2274 2275 // Create a large shared memory region to attach to based on size. 2276 // Currently, size is the total size of the heap 2277 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2278 if (shmid == -1) { 2279 // Possible reasons for shmget failure: 2280 // 1. shmmax is too small for Java heap. 2281 // > check shmmax value: cat /proc/sys/kernel/shmmax 2282 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2283 // 2. not enough large page memory. 2284 // > check available large pages: cat /proc/meminfo 2285 // > increase amount of large pages: 2286 // echo new_value > /proc/sys/vm/nr_hugepages 2287 // Note 1: different Bsd may use different name for this property, 2288 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2289 // Note 2: it's possible there's enough physical memory available but 2290 // they are so fragmented after a long run that they can't 2291 // coalesce into large pages. Try to reserve large pages when 2292 // the system is still "fresh". 2293 if (warn_on_failure) { 2294 warning("Failed to reserve shared memory (errno = %d).", errno); 2295 } 2296 return NULL; 2297 } 2298 2299 // attach to the region 2300 addr = (char*)shmat(shmid, req_addr, 0); 2301 int err = errno; 2302 2303 // Remove shmid. If shmat() is successful, the actual shared memory segment 2304 // will be deleted when it's detached by shmdt() or when the process 2305 // terminates. If shmat() is not successful this will remove the shared 2306 // segment immediately. 2307 shmctl(shmid, IPC_RMID, NULL); 2308 2309 if ((intptr_t)addr == -1) { 2310 if (warn_on_failure) { 2311 warning("Failed to attach shared memory (errno = %d).", err); 2312 } 2313 return NULL; 2314 } 2315 2316 // The memory is committed 2317 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2318 2319 return addr; 2320 } 2321 2322 bool os::release_memory_special(char* base, size_t bytes) { 2323 if (MemTracker::tracking_level() > NMT_minimal) { 2324 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2325 // detaching the SHM segment will also delete it, see reserve_memory_special() 2326 int rslt = shmdt(base); 2327 if (rslt == 0) { 2328 tkr.record((address)base, bytes); 2329 return true; 2330 } else { 2331 return false; 2332 } 2333 } else { 2334 return shmdt(base) == 0; 2335 } 2336 } 2337 2338 size_t os::large_page_size() { 2339 return _large_page_size; 2340 } 2341 2342 // HugeTLBFS allows application to commit large page memory on demand; 2343 // with SysV SHM the entire memory region must be allocated as shared 2344 // memory. 2345 bool os::can_commit_large_page_memory() { 2346 return UseHugeTLBFS; 2347 } 2348 2349 bool os::can_execute_large_page_memory() { 2350 return UseHugeTLBFS; 2351 } 2352 2353 // Reserve memory at an arbitrary address, only if that area is 2354 // available (and not reserved for something else). 2355 2356 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2357 const int max_tries = 10; 2358 char* base[max_tries]; 2359 size_t size[max_tries]; 2360 const size_t gap = 0x000000; 2361 2362 // Assert only that the size is a multiple of the page size, since 2363 // that's all that mmap requires, and since that's all we really know 2364 // about at this low abstraction level. If we need higher alignment, 2365 // we can either pass an alignment to this method or verify alignment 2366 // in one of the methods further up the call chain. See bug 5044738. 2367 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2368 2369 // Repeatedly allocate blocks until the block is allocated at the 2370 // right spot. 2371 2372 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2373 // if kernel honors the hint then we can return immediately. 2374 char * addr = anon_mmap(requested_addr, bytes, false); 2375 if (addr == requested_addr) { 2376 return requested_addr; 2377 } 2378 2379 if (addr != NULL) { 2380 // mmap() is successful but it fails to reserve at the requested address 2381 anon_munmap(addr, bytes); 2382 } 2383 2384 int i; 2385 for (i = 0; i < max_tries; ++i) { 2386 base[i] = reserve_memory(bytes); 2387 2388 if (base[i] != NULL) { 2389 // Is this the block we wanted? 2390 if (base[i] == requested_addr) { 2391 size[i] = bytes; 2392 break; 2393 } 2394 2395 // Does this overlap the block we wanted? Give back the overlapped 2396 // parts and try again. 2397 2398 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2399 if (top_overlap >= 0 && top_overlap < bytes) { 2400 unmap_memory(base[i], top_overlap); 2401 base[i] += top_overlap; 2402 size[i] = bytes - top_overlap; 2403 } else { 2404 size_t bottom_overlap = base[i] + bytes - requested_addr; 2405 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2406 unmap_memory(requested_addr, bottom_overlap); 2407 size[i] = bytes - bottom_overlap; 2408 } else { 2409 size[i] = bytes; 2410 } 2411 } 2412 } 2413 } 2414 2415 // Give back the unused reserved pieces. 2416 2417 for (int j = 0; j < i; ++j) { 2418 if (base[j] != NULL) { 2419 unmap_memory(base[j], size[j]); 2420 } 2421 } 2422 2423 if (i < max_tries) { 2424 return requested_addr; 2425 } else { 2426 return NULL; 2427 } 2428 } 2429 2430 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2431 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2432 } 2433 2434 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2435 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2436 } 2437 2438 void os::naked_short_sleep(jlong ms) { 2439 struct timespec req; 2440 2441 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2442 req.tv_sec = 0; 2443 if (ms > 0) { 2444 req.tv_nsec = (ms % 1000) * 1000000; 2445 } else { 2446 req.tv_nsec = 1; 2447 } 2448 2449 nanosleep(&req, NULL); 2450 2451 return; 2452 } 2453 2454 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2455 void os::infinite_sleep() { 2456 while (true) { // sleep forever ... 2457 ::sleep(100); // ... 100 seconds at a time 2458 } 2459 } 2460 2461 // Used to convert frequent JVM_Yield() to nops 2462 bool os::dont_yield() { 2463 return DontYieldALot; 2464 } 2465 2466 void os::naked_yield() { 2467 sched_yield(); 2468 } 2469 2470 //////////////////////////////////////////////////////////////////////////////// 2471 // thread priority support 2472 2473 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2474 // only supports dynamic priority, static priority must be zero. For real-time 2475 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2476 // However, for large multi-threaded applications, SCHED_RR is not only slower 2477 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2478 // of 5 runs - Sep 2005). 2479 // 2480 // The following code actually changes the niceness of kernel-thread/LWP. It 2481 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2482 // not the entire user process, and user level threads are 1:1 mapped to kernel 2483 // threads. It has always been the case, but could change in the future. For 2484 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2485 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2486 2487 #if !defined(__APPLE__) 2488 int os::java_to_os_priority[CriticalPriority + 1] = { 2489 19, // 0 Entry should never be used 2490 2491 0, // 1 MinPriority 2492 3, // 2 2493 6, // 3 2494 2495 10, // 4 2496 15, // 5 NormPriority 2497 18, // 6 2498 2499 21, // 7 2500 25, // 8 2501 28, // 9 NearMaxPriority 2502 2503 31, // 10 MaxPriority 2504 2505 31 // 11 CriticalPriority 2506 }; 2507 #else 2508 // Using Mach high-level priority assignments 2509 int os::java_to_os_priority[CriticalPriority + 1] = { 2510 0, // 0 Entry should never be used (MINPRI_USER) 2511 2512 27, // 1 MinPriority 2513 28, // 2 2514 29, // 3 2515 2516 30, // 4 2517 31, // 5 NormPriority (BASEPRI_DEFAULT) 2518 32, // 6 2519 2520 33, // 7 2521 34, // 8 2522 35, // 9 NearMaxPriority 2523 2524 36, // 10 MaxPriority 2525 2526 36 // 11 CriticalPriority 2527 }; 2528 #endif 2529 2530 static int prio_init() { 2531 if (ThreadPriorityPolicy == 1) { 2532 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2533 // if effective uid is not root. Perhaps, a more elegant way of doing 2534 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2535 if (geteuid() != 0) { 2536 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2537 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2538 } 2539 ThreadPriorityPolicy = 0; 2540 } 2541 } 2542 if (UseCriticalJavaThreadPriority) { 2543 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2544 } 2545 return 0; 2546 } 2547 2548 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2549 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2550 2551 #ifdef __OpenBSD__ 2552 // OpenBSD pthread_setprio starves low priority threads 2553 return OS_OK; 2554 #elif defined(__FreeBSD__) 2555 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2556 #elif defined(__APPLE__) || defined(__NetBSD__) 2557 struct sched_param sp; 2558 int policy; 2559 pthread_t self = pthread_self(); 2560 2561 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2562 return OS_ERR; 2563 } 2564 2565 sp.sched_priority = newpri; 2566 if (pthread_setschedparam(self, policy, &sp) != 0) { 2567 return OS_ERR; 2568 } 2569 2570 return OS_OK; 2571 #else 2572 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2573 return (ret == 0) ? OS_OK : OS_ERR; 2574 #endif 2575 } 2576 2577 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2578 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2579 *priority_ptr = java_to_os_priority[NormPriority]; 2580 return OS_OK; 2581 } 2582 2583 errno = 0; 2584 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2585 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2586 #elif defined(__APPLE__) || defined(__NetBSD__) 2587 int policy; 2588 struct sched_param sp; 2589 2590 pthread_getschedparam(pthread_self(), &policy, &sp); 2591 *priority_ptr = sp.sched_priority; 2592 #else 2593 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2594 #endif 2595 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2596 } 2597 2598 // Hint to the underlying OS that a task switch would not be good. 2599 // Void return because it's a hint and can fail. 2600 void os::hint_no_preempt() {} 2601 2602 //////////////////////////////////////////////////////////////////////////////// 2603 // suspend/resume support 2604 2605 // The low-level signal-based suspend/resume support is a remnant from the 2606 // old VM-suspension that used to be for java-suspension, safepoints etc, 2607 // within hotspot. Currently used by JFR's OSThreadSampler 2608 // 2609 // The remaining code is greatly simplified from the more general suspension 2610 // code that used to be used. 2611 // 2612 // The protocol is quite simple: 2613 // - suspend: 2614 // - sends a signal to the target thread 2615 // - polls the suspend state of the osthread using a yield loop 2616 // - target thread signal handler (SR_handler) sets suspend state 2617 // and blocks in sigsuspend until continued 2618 // - resume: 2619 // - sets target osthread state to continue 2620 // - sends signal to end the sigsuspend loop in the SR_handler 2621 // 2622 // Note that the SR_lock plays no role in this suspend/resume protocol, 2623 // but is checked for NULL in SR_handler as a thread termination indicator. 2624 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs. 2625 // 2626 // Note that resume_clear_context() and suspend_save_context() are needed 2627 // by SR_handler(), so that fetch_frame_from_ucontext() works, 2628 // which in part is used by: 2629 // - Forte Analyzer: AsyncGetCallTrace() 2630 // - StackBanging: get_frame_at_stack_banging_point() 2631 2632 static void resume_clear_context(OSThread *osthread) { 2633 osthread->set_ucontext(NULL); 2634 osthread->set_siginfo(NULL); 2635 } 2636 2637 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2638 osthread->set_ucontext(context); 2639 osthread->set_siginfo(siginfo); 2640 } 2641 2642 // Handler function invoked when a thread's execution is suspended or 2643 // resumed. We have to be careful that only async-safe functions are 2644 // called here (Note: most pthread functions are not async safe and 2645 // should be avoided.) 2646 // 2647 // Note: sigwait() is a more natural fit than sigsuspend() from an 2648 // interface point of view, but sigwait() prevents the signal hander 2649 // from being run. libpthread would get very confused by not having 2650 // its signal handlers run and prevents sigwait()'s use with the 2651 // mutex granting granting signal. 2652 // 2653 // Currently only ever called on the VMThread or JavaThread 2654 // 2655 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2656 // Save and restore errno to avoid confusing native code with EINTR 2657 // after sigsuspend. 2658 int old_errno = errno; 2659 2660 Thread* thread = Thread::current_or_null_safe(); 2661 assert(thread != NULL, "Missing current thread in SR_handler"); 2662 2663 // On some systems we have seen signal delivery get "stuck" until the signal 2664 // mask is changed as part of thread termination. Check that the current thread 2665 // has not already terminated (via SR_lock()) - else the following assertion 2666 // will fail because the thread is no longer a JavaThread as the ~JavaThread 2667 // destructor has completed. 2668 2669 if (thread->SR_lock() == NULL) { 2670 return; 2671 } 2672 2673 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2674 2675 OSThread* osthread = thread->osthread(); 2676 2677 os::SuspendResume::State current = osthread->sr.state(); 2678 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2679 suspend_save_context(osthread, siginfo, context); 2680 2681 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2682 os::SuspendResume::State state = osthread->sr.suspended(); 2683 if (state == os::SuspendResume::SR_SUSPENDED) { 2684 sigset_t suspend_set; // signals for sigsuspend() 2685 2686 // get current set of blocked signals and unblock resume signal 2687 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2688 sigdelset(&suspend_set, SR_signum); 2689 2690 sr_semaphore.signal(); 2691 // wait here until we are resumed 2692 while (1) { 2693 sigsuspend(&suspend_set); 2694 2695 os::SuspendResume::State result = osthread->sr.running(); 2696 if (result == os::SuspendResume::SR_RUNNING) { 2697 sr_semaphore.signal(); 2698 break; 2699 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2700 ShouldNotReachHere(); 2701 } 2702 } 2703 2704 } else if (state == os::SuspendResume::SR_RUNNING) { 2705 // request was cancelled, continue 2706 } else { 2707 ShouldNotReachHere(); 2708 } 2709 2710 resume_clear_context(osthread); 2711 } else if (current == os::SuspendResume::SR_RUNNING) { 2712 // request was cancelled, continue 2713 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2714 // ignore 2715 } else { 2716 // ignore 2717 } 2718 2719 errno = old_errno; 2720 } 2721 2722 2723 static int SR_initialize() { 2724 struct sigaction act; 2725 char *s; 2726 // Get signal number to use for suspend/resume 2727 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2728 int sig = ::strtol(s, 0, 10); 2729 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769. 2730 sig < NSIG) { // Must be legal signal and fit into sigflags[]. 2731 SR_signum = sig; 2732 } else { 2733 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.", 2734 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum); 2735 } 2736 } 2737 2738 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2739 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2740 2741 sigemptyset(&SR_sigset); 2742 sigaddset(&SR_sigset, SR_signum); 2743 2744 // Set up signal handler for suspend/resume 2745 act.sa_flags = SA_RESTART|SA_SIGINFO; 2746 act.sa_handler = (void (*)(int)) SR_handler; 2747 2748 // SR_signum is blocked by default. 2749 // 4528190 - We also need to block pthread restart signal (32 on all 2750 // supported Bsd platforms). Note that BsdThreads need to block 2751 // this signal for all threads to work properly. So we don't have 2752 // to use hard-coded signal number when setting up the mask. 2753 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2754 2755 if (sigaction(SR_signum, &act, 0) == -1) { 2756 return -1; 2757 } 2758 2759 // Save signal flag 2760 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2761 return 0; 2762 } 2763 2764 static int sr_notify(OSThread* osthread) { 2765 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2766 assert_status(status == 0, status, "pthread_kill"); 2767 return status; 2768 } 2769 2770 // "Randomly" selected value for how long we want to spin 2771 // before bailing out on suspending a thread, also how often 2772 // we send a signal to a thread we want to resume 2773 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2774 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2775 2776 // returns true on success and false on error - really an error is fatal 2777 // but this seems the normal response to library errors 2778 static bool do_suspend(OSThread* osthread) { 2779 assert(osthread->sr.is_running(), "thread should be running"); 2780 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2781 2782 // mark as suspended and send signal 2783 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2784 // failed to switch, state wasn't running? 2785 ShouldNotReachHere(); 2786 return false; 2787 } 2788 2789 if (sr_notify(osthread) != 0) { 2790 ShouldNotReachHere(); 2791 } 2792 2793 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2794 while (true) { 2795 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2796 break; 2797 } else { 2798 // timeout 2799 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2800 if (cancelled == os::SuspendResume::SR_RUNNING) { 2801 return false; 2802 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2803 // make sure that we consume the signal on the semaphore as well 2804 sr_semaphore.wait(); 2805 break; 2806 } else { 2807 ShouldNotReachHere(); 2808 return false; 2809 } 2810 } 2811 } 2812 2813 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2814 return true; 2815 } 2816 2817 static void do_resume(OSThread* osthread) { 2818 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2819 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2820 2821 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2822 // failed to switch to WAKEUP_REQUEST 2823 ShouldNotReachHere(); 2824 return; 2825 } 2826 2827 while (true) { 2828 if (sr_notify(osthread) == 0) { 2829 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2830 if (osthread->sr.is_running()) { 2831 return; 2832 } 2833 } 2834 } else { 2835 ShouldNotReachHere(); 2836 } 2837 } 2838 2839 guarantee(osthread->sr.is_running(), "Must be running!"); 2840 } 2841 2842 /////////////////////////////////////////////////////////////////////////////////// 2843 // signal handling (except suspend/resume) 2844 2845 // This routine may be used by user applications as a "hook" to catch signals. 2846 // The user-defined signal handler must pass unrecognized signals to this 2847 // routine, and if it returns true (non-zero), then the signal handler must 2848 // return immediately. If the flag "abort_if_unrecognized" is true, then this 2849 // routine will never retun false (zero), but instead will execute a VM panic 2850 // routine kill the process. 2851 // 2852 // If this routine returns false, it is OK to call it again. This allows 2853 // the user-defined signal handler to perform checks either before or after 2854 // the VM performs its own checks. Naturally, the user code would be making 2855 // a serious error if it tried to handle an exception (such as a null check 2856 // or breakpoint) that the VM was generating for its own correct operation. 2857 // 2858 // This routine may recognize any of the following kinds of signals: 2859 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2860 // It should be consulted by handlers for any of those signals. 2861 // 2862 // The caller of this routine must pass in the three arguments supplied 2863 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 2864 // field of the structure passed to sigaction(). This routine assumes that 2865 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2866 // 2867 // Note that the VM will print warnings if it detects conflicting signal 2868 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2869 // 2870 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2871 void* ucontext, 2872 int abort_if_unrecognized); 2873 2874 void signalHandler(int sig, siginfo_t* info, void* uc) { 2875 assert(info != NULL && uc != NULL, "it must be old kernel"); 2876 int orig_errno = errno; // Preserve errno value over signal handler. 2877 JVM_handle_bsd_signal(sig, info, uc, true); 2878 errno = orig_errno; 2879 } 2880 2881 2882 // This boolean allows users to forward their own non-matching signals 2883 // to JVM_handle_bsd_signal, harmlessly. 2884 bool os::Bsd::signal_handlers_are_installed = false; 2885 2886 // For signal-chaining 2887 struct sigaction sigact[NSIG]; 2888 uint32_t sigs = 0; 2889 #if (32 < NSIG-1) 2890 #error "Not all signals can be encoded in sigs. Adapt its type!" 2891 #endif 2892 bool os::Bsd::libjsig_is_loaded = false; 2893 typedef struct sigaction *(*get_signal_t)(int); 2894 get_signal_t os::Bsd::get_signal_action = NULL; 2895 2896 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2897 struct sigaction *actp = NULL; 2898 2899 if (libjsig_is_loaded) { 2900 // Retrieve the old signal handler from libjsig 2901 actp = (*get_signal_action)(sig); 2902 } 2903 if (actp == NULL) { 2904 // Retrieve the preinstalled signal handler from jvm 2905 actp = get_preinstalled_handler(sig); 2906 } 2907 2908 return actp; 2909 } 2910 2911 static bool call_chained_handler(struct sigaction *actp, int sig, 2912 siginfo_t *siginfo, void *context) { 2913 // Call the old signal handler 2914 if (actp->sa_handler == SIG_DFL) { 2915 // It's more reasonable to let jvm treat it as an unexpected exception 2916 // instead of taking the default action. 2917 return false; 2918 } else if (actp->sa_handler != SIG_IGN) { 2919 if ((actp->sa_flags & SA_NODEFER) == 0) { 2920 // automaticlly block the signal 2921 sigaddset(&(actp->sa_mask), sig); 2922 } 2923 2924 sa_handler_t hand; 2925 sa_sigaction_t sa; 2926 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 2927 // retrieve the chained handler 2928 if (siginfo_flag_set) { 2929 sa = actp->sa_sigaction; 2930 } else { 2931 hand = actp->sa_handler; 2932 } 2933 2934 if ((actp->sa_flags & SA_RESETHAND) != 0) { 2935 actp->sa_handler = SIG_DFL; 2936 } 2937 2938 // try to honor the signal mask 2939 sigset_t oset; 2940 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 2941 2942 // call into the chained handler 2943 if (siginfo_flag_set) { 2944 (*sa)(sig, siginfo, context); 2945 } else { 2946 (*hand)(sig); 2947 } 2948 2949 // restore the signal mask 2950 pthread_sigmask(SIG_SETMASK, &oset, 0); 2951 } 2952 // Tell jvm's signal handler the signal is taken care of. 2953 return true; 2954 } 2955 2956 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 2957 bool chained = false; 2958 // signal-chaining 2959 if (UseSignalChaining) { 2960 struct sigaction *actp = get_chained_signal_action(sig); 2961 if (actp != NULL) { 2962 chained = call_chained_handler(actp, sig, siginfo, context); 2963 } 2964 } 2965 return chained; 2966 } 2967 2968 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 2969 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) { 2970 return &sigact[sig]; 2971 } 2972 return NULL; 2973 } 2974 2975 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 2976 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2977 sigact[sig] = oldAct; 2978 sigs |= (uint32_t)1 << (sig-1); 2979 } 2980 2981 // for diagnostic 2982 int sigflags[NSIG]; 2983 2984 int os::Bsd::get_our_sigflags(int sig) { 2985 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2986 return sigflags[sig]; 2987 } 2988 2989 void os::Bsd::set_our_sigflags(int sig, int flags) { 2990 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2991 if (sig > 0 && sig < NSIG) { 2992 sigflags[sig] = flags; 2993 } 2994 } 2995 2996 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 2997 // Check for overwrite. 2998 struct sigaction oldAct; 2999 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3000 3001 void* oldhand = oldAct.sa_sigaction 3002 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3003 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3004 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3005 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3006 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3007 if (AllowUserSignalHandlers || !set_installed) { 3008 // Do not overwrite; user takes responsibility to forward to us. 3009 return; 3010 } else if (UseSignalChaining) { 3011 // save the old handler in jvm 3012 save_preinstalled_handler(sig, oldAct); 3013 // libjsig also interposes the sigaction() call below and saves the 3014 // old sigaction on it own. 3015 } else { 3016 fatal("Encountered unexpected pre-existing sigaction handler " 3017 "%#lx for signal %d.", (long)oldhand, sig); 3018 } 3019 } 3020 3021 struct sigaction sigAct; 3022 sigfillset(&(sigAct.sa_mask)); 3023 sigAct.sa_handler = SIG_DFL; 3024 if (!set_installed) { 3025 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3026 } else { 3027 sigAct.sa_sigaction = signalHandler; 3028 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3029 } 3030 #ifdef __APPLE__ 3031 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3032 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3033 // if the signal handler declares it will handle it on alternate stack. 3034 // Notice we only declare we will handle it on alt stack, but we are not 3035 // actually going to use real alt stack - this is just a workaround. 3036 // Please see ux_exception.c, method catch_mach_exception_raise for details 3037 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3038 if (sig == SIGSEGV) { 3039 sigAct.sa_flags |= SA_ONSTACK; 3040 } 3041 #endif 3042 3043 // Save flags, which are set by ours 3044 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 3045 sigflags[sig] = sigAct.sa_flags; 3046 3047 int ret = sigaction(sig, &sigAct, &oldAct); 3048 assert(ret == 0, "check"); 3049 3050 void* oldhand2 = oldAct.sa_sigaction 3051 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3052 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3053 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3054 } 3055 3056 // install signal handlers for signals that HotSpot needs to 3057 // handle in order to support Java-level exception handling. 3058 3059 void os::Bsd::install_signal_handlers() { 3060 if (!signal_handlers_are_installed) { 3061 signal_handlers_are_installed = true; 3062 3063 // signal-chaining 3064 typedef void (*signal_setting_t)(); 3065 signal_setting_t begin_signal_setting = NULL; 3066 signal_setting_t end_signal_setting = NULL; 3067 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3068 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3069 if (begin_signal_setting != NULL) { 3070 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3071 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3072 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3073 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3074 libjsig_is_loaded = true; 3075 assert(UseSignalChaining, "should enable signal-chaining"); 3076 } 3077 if (libjsig_is_loaded) { 3078 // Tell libjsig jvm is setting signal handlers 3079 (*begin_signal_setting)(); 3080 } 3081 3082 set_signal_handler(SIGSEGV, true); 3083 set_signal_handler(SIGPIPE, true); 3084 set_signal_handler(SIGBUS, true); 3085 set_signal_handler(SIGILL, true); 3086 set_signal_handler(SIGFPE, true); 3087 set_signal_handler(SIGXFSZ, true); 3088 3089 #if defined(__APPLE__) 3090 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3091 // signals caught and handled by the JVM. To work around this, we reset the mach task 3092 // signal handler that's placed on our process by CrashReporter. This disables 3093 // CrashReporter-based reporting. 3094 // 3095 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3096 // on caught fatal signals. 3097 // 3098 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3099 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3100 // exception handling, while leaving the standard BSD signal handlers functional. 3101 kern_return_t kr; 3102 kr = task_set_exception_ports(mach_task_self(), 3103 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3104 MACH_PORT_NULL, 3105 EXCEPTION_STATE_IDENTITY, 3106 MACHINE_THREAD_STATE); 3107 3108 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3109 #endif 3110 3111 if (libjsig_is_loaded) { 3112 // Tell libjsig jvm finishes setting signal handlers 3113 (*end_signal_setting)(); 3114 } 3115 3116 // We don't activate signal checker if libjsig is in place, we trust ourselves 3117 // and if UserSignalHandler is installed all bets are off 3118 if (CheckJNICalls) { 3119 if (libjsig_is_loaded) { 3120 if (PrintJNIResolving) { 3121 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3122 } 3123 check_signals = false; 3124 } 3125 if (AllowUserSignalHandlers) { 3126 if (PrintJNIResolving) { 3127 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3128 } 3129 check_signals = false; 3130 } 3131 } 3132 } 3133 } 3134 3135 3136 ///// 3137 // glibc on Bsd platform uses non-documented flag 3138 // to indicate, that some special sort of signal 3139 // trampoline is used. 3140 // We will never set this flag, and we should 3141 // ignore this flag in our diagnostic 3142 #ifdef SIGNIFICANT_SIGNAL_MASK 3143 #undef SIGNIFICANT_SIGNAL_MASK 3144 #endif 3145 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3146 3147 static const char* get_signal_handler_name(address handler, 3148 char* buf, int buflen) { 3149 int offset; 3150 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3151 if (found) { 3152 // skip directory names 3153 const char *p1, *p2; 3154 p1 = buf; 3155 size_t len = strlen(os::file_separator()); 3156 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3157 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3158 } else { 3159 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3160 } 3161 return buf; 3162 } 3163 3164 static void print_signal_handler(outputStream* st, int sig, 3165 char* buf, size_t buflen) { 3166 struct sigaction sa; 3167 3168 sigaction(sig, NULL, &sa); 3169 3170 // See comment for SIGNIFICANT_SIGNAL_MASK define 3171 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3172 3173 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3174 3175 address handler = (sa.sa_flags & SA_SIGINFO) 3176 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3177 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3178 3179 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3180 st->print("SIG_DFL"); 3181 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3182 st->print("SIG_IGN"); 3183 } else { 3184 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3185 } 3186 3187 st->print(", sa_mask[0]="); 3188 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3189 3190 address rh = VMError::get_resetted_sighandler(sig); 3191 // May be, handler was resetted by VMError? 3192 if (rh != NULL) { 3193 handler = rh; 3194 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3195 } 3196 3197 st->print(", sa_flags="); 3198 os::Posix::print_sa_flags(st, sa.sa_flags); 3199 3200 // Check: is it our handler? 3201 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3202 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3203 // It is our signal handler 3204 // check for flags, reset system-used one! 3205 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3206 st->print( 3207 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3208 os::Bsd::get_our_sigflags(sig)); 3209 } 3210 } 3211 st->cr(); 3212 } 3213 3214 3215 #define DO_SIGNAL_CHECK(sig) \ 3216 do { \ 3217 if (!sigismember(&check_signal_done, sig)) { \ 3218 os::Bsd::check_signal_handler(sig); \ 3219 } \ 3220 } while (0) 3221 3222 // This method is a periodic task to check for misbehaving JNI applications 3223 // under CheckJNI, we can add any periodic checks here 3224 3225 void os::run_periodic_checks() { 3226 3227 if (check_signals == false) return; 3228 3229 // SEGV and BUS if overridden could potentially prevent 3230 // generation of hs*.log in the event of a crash, debugging 3231 // such a case can be very challenging, so we absolutely 3232 // check the following for a good measure: 3233 DO_SIGNAL_CHECK(SIGSEGV); 3234 DO_SIGNAL_CHECK(SIGILL); 3235 DO_SIGNAL_CHECK(SIGFPE); 3236 DO_SIGNAL_CHECK(SIGBUS); 3237 DO_SIGNAL_CHECK(SIGPIPE); 3238 DO_SIGNAL_CHECK(SIGXFSZ); 3239 3240 3241 // ReduceSignalUsage allows the user to override these handlers 3242 // see comments at the very top and jvm_md.h 3243 if (!ReduceSignalUsage) { 3244 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3245 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3246 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3247 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3248 } 3249 3250 DO_SIGNAL_CHECK(SR_signum); 3251 } 3252 3253 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3254 3255 static os_sigaction_t os_sigaction = NULL; 3256 3257 void os::Bsd::check_signal_handler(int sig) { 3258 char buf[O_BUFLEN]; 3259 address jvmHandler = NULL; 3260 3261 3262 struct sigaction act; 3263 if (os_sigaction == NULL) { 3264 // only trust the default sigaction, in case it has been interposed 3265 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3266 if (os_sigaction == NULL) return; 3267 } 3268 3269 os_sigaction(sig, (struct sigaction*)NULL, &act); 3270 3271 3272 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3273 3274 address thisHandler = (act.sa_flags & SA_SIGINFO) 3275 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3276 : CAST_FROM_FN_PTR(address, act.sa_handler); 3277 3278 3279 switch (sig) { 3280 case SIGSEGV: 3281 case SIGBUS: 3282 case SIGFPE: 3283 case SIGPIPE: 3284 case SIGILL: 3285 case SIGXFSZ: 3286 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3287 break; 3288 3289 case SHUTDOWN1_SIGNAL: 3290 case SHUTDOWN2_SIGNAL: 3291 case SHUTDOWN3_SIGNAL: 3292 case BREAK_SIGNAL: 3293 jvmHandler = (address)user_handler(); 3294 break; 3295 3296 default: 3297 if (sig == SR_signum) { 3298 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3299 } else { 3300 return; 3301 } 3302 break; 3303 } 3304 3305 if (thisHandler != jvmHandler) { 3306 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3307 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3308 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3309 // No need to check this sig any longer 3310 sigaddset(&check_signal_done, sig); 3311 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3312 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3313 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3314 exception_name(sig, buf, O_BUFLEN)); 3315 } 3316 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3317 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3318 tty->print("expected:"); 3319 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig)); 3320 tty->cr(); 3321 tty->print(" found:"); 3322 os::Posix::print_sa_flags(tty, act.sa_flags); 3323 tty->cr(); 3324 // No need to check this sig any longer 3325 sigaddset(&check_signal_done, sig); 3326 } 3327 3328 // Dump all the signal 3329 if (sigismember(&check_signal_done, sig)) { 3330 print_signal_handlers(tty, buf, O_BUFLEN); 3331 } 3332 } 3333 3334 extern void report_error(char* file_name, int line_no, char* title, 3335 char* format, ...); 3336 3337 // this is called _before_ the most of global arguments have been parsed 3338 void os::init(void) { 3339 char dummy; // used to get a guess on initial stack address 3340 3341 // With BsdThreads the JavaMain thread pid (primordial thread) 3342 // is different than the pid of the java launcher thread. 3343 // So, on Bsd, the launcher thread pid is passed to the VM 3344 // via the sun.java.launcher.pid property. 3345 // Use this property instead of getpid() if it was correctly passed. 3346 // See bug 6351349. 3347 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3348 3349 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3350 3351 clock_tics_per_sec = CLK_TCK; 3352 3353 init_random(1234567); 3354 3355 Bsd::set_page_size(getpagesize()); 3356 if (Bsd::page_size() == -1) { 3357 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno)); 3358 } 3359 init_page_sizes((size_t) Bsd::page_size()); 3360 3361 Bsd::initialize_system_info(); 3362 3363 // main_thread points to the aboriginal thread 3364 Bsd::_main_thread = pthread_self(); 3365 3366 Bsd::clock_init(); 3367 initial_time_count = javaTimeNanos(); 3368 3369 #ifdef __APPLE__ 3370 // XXXDARWIN 3371 // Work around the unaligned VM callbacks in hotspot's 3372 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3373 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3374 // alignment when doing symbol lookup. To work around this, we force early 3375 // binding of all symbols now, thus binding when alignment is known-good. 3376 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3377 #endif 3378 3379 os::Posix::init(); 3380 } 3381 3382 // To install functions for atexit system call 3383 extern "C" { 3384 static void perfMemory_exit_helper() { 3385 perfMemory_exit(); 3386 } 3387 } 3388 3389 // this is called _after_ the global arguments have been parsed 3390 jint os::init_2(void) { 3391 3392 os::Posix::init_2(); 3393 3394 // Allocate a single page and mark it as readable for safepoint polling 3395 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3396 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3397 3398 os::set_polling_page(polling_page); 3399 log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page)); 3400 3401 if (!UseMembar) { 3402 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3403 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3404 os::set_memory_serialize_page(mem_serialize_page); 3405 log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page)); 3406 } 3407 3408 // initialize suspend/resume support - must do this before signal_sets_init() 3409 if (SR_initialize() != 0) { 3410 perror("SR_initialize failed"); 3411 return JNI_ERR; 3412 } 3413 3414 Bsd::signal_sets_init(); 3415 Bsd::install_signal_handlers(); 3416 3417 // Check and sets minimum stack sizes against command line options 3418 if (Posix::set_minimum_stack_sizes() == JNI_ERR) { 3419 return JNI_ERR; 3420 } 3421 3422 if (MaxFDLimit) { 3423 // set the number of file descriptors to max. print out error 3424 // if getrlimit/setrlimit fails but continue regardless. 3425 struct rlimit nbr_files; 3426 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3427 if (status != 0) { 3428 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno)); 3429 } else { 3430 nbr_files.rlim_cur = nbr_files.rlim_max; 3431 3432 #ifdef __APPLE__ 3433 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3434 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3435 // be used instead 3436 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3437 #endif 3438 3439 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3440 if (status != 0) { 3441 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno)); 3442 } 3443 } 3444 } 3445 3446 // at-exit methods are called in the reverse order of their registration. 3447 // atexit functions are called on return from main or as a result of a 3448 // call to exit(3C). There can be only 32 of these functions registered 3449 // and atexit() does not set errno. 3450 3451 if (PerfAllowAtExitRegistration) { 3452 // only register atexit functions if PerfAllowAtExitRegistration is set. 3453 // atexit functions can be delayed until process exit time, which 3454 // can be problematic for embedded VM situations. Embedded VMs should 3455 // call DestroyJavaVM() to assure that VM resources are released. 3456 3457 // note: perfMemory_exit_helper atexit function may be removed in 3458 // the future if the appropriate cleanup code can be added to the 3459 // VM_Exit VMOperation's doit method. 3460 if (atexit(perfMemory_exit_helper) != 0) { 3461 warning("os::init_2 atexit(perfMemory_exit_helper) failed"); 3462 } 3463 } 3464 3465 // initialize thread priority policy 3466 prio_init(); 3467 3468 #ifdef __APPLE__ 3469 // dynamically link to objective c gc registration 3470 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3471 if (handleLibObjc != NULL) { 3472 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3473 } 3474 #endif 3475 3476 return JNI_OK; 3477 } 3478 3479 // Mark the polling page as unreadable 3480 void os::make_polling_page_unreadable(void) { 3481 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3482 fatal("Could not disable polling page"); 3483 } 3484 } 3485 3486 // Mark the polling page as readable 3487 void os::make_polling_page_readable(void) { 3488 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3489 fatal("Could not enable polling page"); 3490 } 3491 } 3492 3493 int os::active_processor_count() { 3494 return _processor_count; 3495 } 3496 3497 void os::set_native_thread_name(const char *name) { 3498 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3499 // This is only supported in Snow Leopard and beyond 3500 if (name != NULL) { 3501 // Add a "Java: " prefix to the name 3502 char buf[MAXTHREADNAMESIZE]; 3503 snprintf(buf, sizeof(buf), "Java: %s", name); 3504 pthread_setname_np(buf); 3505 } 3506 #endif 3507 } 3508 3509 bool os::distribute_processes(uint length, uint* distribution) { 3510 // Not yet implemented. 3511 return false; 3512 } 3513 3514 bool os::bind_to_processor(uint processor_id) { 3515 // Not yet implemented. 3516 return false; 3517 } 3518 3519 void os::SuspendedThreadTask::internal_do_task() { 3520 if (do_suspend(_thread->osthread())) { 3521 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3522 do_task(context); 3523 do_resume(_thread->osthread()); 3524 } 3525 } 3526 3527 //////////////////////////////////////////////////////////////////////////////// 3528 // debug support 3529 3530 bool os::find(address addr, outputStream* st) { 3531 Dl_info dlinfo; 3532 memset(&dlinfo, 0, sizeof(dlinfo)); 3533 if (dladdr(addr, &dlinfo) != 0) { 3534 st->print(INTPTR_FORMAT ": ", (intptr_t)addr); 3535 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3536 st->print("%s+%#x", dlinfo.dli_sname, 3537 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr)); 3538 } else if (dlinfo.dli_fbase != NULL) { 3539 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase)); 3540 } else { 3541 st->print("<absolute address>"); 3542 } 3543 if (dlinfo.dli_fname != NULL) { 3544 st->print(" in %s", dlinfo.dli_fname); 3545 } 3546 if (dlinfo.dli_fbase != NULL) { 3547 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase); 3548 } 3549 st->cr(); 3550 3551 if (Verbose) { 3552 // decode some bytes around the PC 3553 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3554 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3555 address lowest = (address) dlinfo.dli_sname; 3556 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3557 if (begin < lowest) begin = lowest; 3558 Dl_info dlinfo2; 3559 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3560 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3561 end = (address) dlinfo2.dli_saddr; 3562 } 3563 Disassembler::decode(begin, end, st); 3564 } 3565 return true; 3566 } 3567 return false; 3568 } 3569 3570 //////////////////////////////////////////////////////////////////////////////// 3571 // misc 3572 3573 // This does not do anything on Bsd. This is basically a hook for being 3574 // able to use structured exception handling (thread-local exception filters) 3575 // on, e.g., Win32. 3576 void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3577 const methodHandle& method, JavaCallArguments* args, 3578 Thread* thread) { 3579 f(value, method, args, thread); 3580 } 3581 3582 void os::print_statistics() { 3583 } 3584 3585 bool os::message_box(const char* title, const char* message) { 3586 int i; 3587 fdStream err(defaultStream::error_fd()); 3588 for (i = 0; i < 78; i++) err.print_raw("="); 3589 err.cr(); 3590 err.print_raw_cr(title); 3591 for (i = 0; i < 78; i++) err.print_raw("-"); 3592 err.cr(); 3593 err.print_raw_cr(message); 3594 for (i = 0; i < 78; i++) err.print_raw("="); 3595 err.cr(); 3596 3597 char buf[16]; 3598 // Prevent process from exiting upon "read error" without consuming all CPU 3599 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3600 3601 return buf[0] == 'y' || buf[0] == 'Y'; 3602 } 3603 3604 int os::stat(const char *path, struct stat *sbuf) { 3605 char pathbuf[MAX_PATH]; 3606 if (strlen(path) > MAX_PATH - 1) { 3607 errno = ENAMETOOLONG; 3608 return -1; 3609 } 3610 os::native_path(strcpy(pathbuf, path)); 3611 return ::stat(pathbuf, sbuf); 3612 } 3613 3614 static inline struct timespec get_mtime(const char* filename) { 3615 struct stat st; 3616 int ret = os::stat(filename, &st); 3617 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno)); 3618 #ifdef __APPLE__ 3619 return st.st_mtimespec; 3620 #else 3621 return st.st_mtim; 3622 #endif 3623 } 3624 3625 int os::compare_file_modified_times(const char* file1, const char* file2) { 3626 struct timespec filetime1 = get_mtime(file1); 3627 struct timespec filetime2 = get_mtime(file2); 3628 int diff = filetime1.tv_sec - filetime2.tv_sec; 3629 if (diff == 0) { 3630 return filetime1.tv_nsec - filetime2.tv_nsec; 3631 } 3632 return diff; 3633 } 3634 3635 // Is a (classpath) directory empty? 3636 bool os::dir_is_empty(const char* path) { 3637 DIR *dir = NULL; 3638 struct dirent *ptr; 3639 3640 dir = opendir(path); 3641 if (dir == NULL) return true; 3642 3643 // Scan the directory 3644 bool result = true; 3645 char buf[sizeof(struct dirent) + MAX_PATH]; 3646 while (result && (ptr = ::readdir(dir)) != NULL) { 3647 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3648 result = false; 3649 } 3650 } 3651 closedir(dir); 3652 return result; 3653 } 3654 3655 // This code originates from JDK's sysOpen and open64_w 3656 // from src/solaris/hpi/src/system_md.c 3657 3658 int os::open(const char *path, int oflag, int mode) { 3659 if (strlen(path) > MAX_PATH - 1) { 3660 errno = ENAMETOOLONG; 3661 return -1; 3662 } 3663 int fd; 3664 3665 fd = ::open(path, oflag, mode); 3666 if (fd == -1) return -1; 3667 3668 // If the open succeeded, the file might still be a directory 3669 { 3670 struct stat buf; 3671 int ret = ::fstat(fd, &buf); 3672 int st_mode = buf.st_mode; 3673 3674 if (ret != -1) { 3675 if ((st_mode & S_IFMT) == S_IFDIR) { 3676 errno = EISDIR; 3677 ::close(fd); 3678 return -1; 3679 } 3680 } else { 3681 ::close(fd); 3682 return -1; 3683 } 3684 } 3685 3686 // All file descriptors that are opened in the JVM and not 3687 // specifically destined for a subprocess should have the 3688 // close-on-exec flag set. If we don't set it, then careless 3rd 3689 // party native code might fork and exec without closing all 3690 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3691 // UNIXProcess.c), and this in turn might: 3692 // 3693 // - cause end-of-file to fail to be detected on some file 3694 // descriptors, resulting in mysterious hangs, or 3695 // 3696 // - might cause an fopen in the subprocess to fail on a system 3697 // suffering from bug 1085341. 3698 // 3699 // (Yes, the default setting of the close-on-exec flag is a Unix 3700 // design flaw) 3701 // 3702 // See: 3703 // 1085341: 32-bit stdio routines should support file descriptors >255 3704 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3705 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3706 // 3707 #ifdef FD_CLOEXEC 3708 { 3709 int flags = ::fcntl(fd, F_GETFD); 3710 if (flags != -1) { 3711 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3712 } 3713 } 3714 #endif 3715 3716 return fd; 3717 } 3718 3719 3720 // create binary file, rewriting existing file if required 3721 int os::create_binary_file(const char* path, bool rewrite_existing) { 3722 int oflags = O_WRONLY | O_CREAT; 3723 if (!rewrite_existing) { 3724 oflags |= O_EXCL; 3725 } 3726 return ::open(path, oflags, S_IREAD | S_IWRITE); 3727 } 3728 3729 // return current position of file pointer 3730 jlong os::current_file_offset(int fd) { 3731 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3732 } 3733 3734 // move file pointer to the specified offset 3735 jlong os::seek_to_file_offset(int fd, jlong offset) { 3736 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3737 } 3738 3739 // This code originates from JDK's sysAvailable 3740 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3741 3742 int os::available(int fd, jlong *bytes) { 3743 jlong cur, end; 3744 int mode; 3745 struct stat buf; 3746 3747 if (::fstat(fd, &buf) >= 0) { 3748 mode = buf.st_mode; 3749 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3750 int n; 3751 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3752 *bytes = n; 3753 return 1; 3754 } 3755 } 3756 } 3757 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3758 return 0; 3759 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3760 return 0; 3761 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3762 return 0; 3763 } 3764 *bytes = end - cur; 3765 return 1; 3766 } 3767 3768 // Map a block of memory. 3769 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3770 char *addr, size_t bytes, bool read_only, 3771 bool allow_exec) { 3772 int prot; 3773 int flags; 3774 3775 if (read_only) { 3776 prot = PROT_READ; 3777 flags = MAP_SHARED; 3778 } else { 3779 prot = PROT_READ | PROT_WRITE; 3780 flags = MAP_PRIVATE; 3781 } 3782 3783 if (allow_exec) { 3784 prot |= PROT_EXEC; 3785 } 3786 3787 if (addr != NULL) { 3788 flags |= MAP_FIXED; 3789 } 3790 3791 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3792 fd, file_offset); 3793 if (mapped_address == MAP_FAILED) { 3794 return NULL; 3795 } 3796 return mapped_address; 3797 } 3798 3799 3800 // Remap a block of memory. 3801 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3802 char *addr, size_t bytes, bool read_only, 3803 bool allow_exec) { 3804 // same as map_memory() on this OS 3805 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3806 allow_exec); 3807 } 3808 3809 3810 // Unmap a block of memory. 3811 bool os::pd_unmap_memory(char* addr, size_t bytes) { 3812 return munmap(addr, bytes) == 0; 3813 } 3814 3815 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3816 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 3817 // of a thread. 3818 // 3819 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 3820 // the fast estimate available on the platform. 3821 3822 jlong os::current_thread_cpu_time() { 3823 #ifdef __APPLE__ 3824 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 3825 #else 3826 Unimplemented(); 3827 return 0; 3828 #endif 3829 } 3830 3831 jlong os::thread_cpu_time(Thread* thread) { 3832 #ifdef __APPLE__ 3833 return os::thread_cpu_time(thread, true /* user + sys */); 3834 #else 3835 Unimplemented(); 3836 return 0; 3837 #endif 3838 } 3839 3840 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 3841 #ifdef __APPLE__ 3842 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 3843 #else 3844 Unimplemented(); 3845 return 0; 3846 #endif 3847 } 3848 3849 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 3850 #ifdef __APPLE__ 3851 struct thread_basic_info tinfo; 3852 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 3853 kern_return_t kr; 3854 thread_t mach_thread; 3855 3856 mach_thread = thread->osthread()->thread_id(); 3857 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 3858 if (kr != KERN_SUCCESS) { 3859 return -1; 3860 } 3861 3862 if (user_sys_cpu_time) { 3863 jlong nanos; 3864 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 3865 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 3866 return nanos; 3867 } else { 3868 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 3869 } 3870 #else 3871 Unimplemented(); 3872 return 0; 3873 #endif 3874 } 3875 3876 3877 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3878 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3879 info_ptr->may_skip_backward = false; // elapsed time not wall time 3880 info_ptr->may_skip_forward = false; // elapsed time not wall time 3881 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3882 } 3883 3884 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3885 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3886 info_ptr->may_skip_backward = false; // elapsed time not wall time 3887 info_ptr->may_skip_forward = false; // elapsed time not wall time 3888 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3889 } 3890 3891 bool os::is_thread_cpu_time_supported() { 3892 #ifdef __APPLE__ 3893 return true; 3894 #else 3895 return false; 3896 #endif 3897 } 3898 3899 // System loadavg support. Returns -1 if load average cannot be obtained. 3900 // Bsd doesn't yet have a (official) notion of processor sets, 3901 // so just return the system wide load average. 3902 int os::loadavg(double loadavg[], int nelem) { 3903 return ::getloadavg(loadavg, nelem); 3904 } 3905 3906 void os::pause() { 3907 char filename[MAX_PATH]; 3908 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 3909 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 3910 } else { 3911 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 3912 } 3913 3914 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 3915 if (fd != -1) { 3916 struct stat buf; 3917 ::close(fd); 3918 while (::stat(filename, &buf) == 0) { 3919 (void)::poll(NULL, 0, 100); 3920 } 3921 } else { 3922 jio_fprintf(stderr, 3923 "Could not open pause file '%s', continuing immediately.\n", filename); 3924 } 3925 } 3926 3927 // Darwin has no "environ" in a dynamic library. 3928 #ifdef __APPLE__ 3929 #include <crt_externs.h> 3930 #define environ (*_NSGetEnviron()) 3931 #else 3932 extern char** environ; 3933 #endif 3934 3935 // Run the specified command in a separate process. Return its exit value, 3936 // or -1 on failure (e.g. can't fork a new process). 3937 // Unlike system(), this function can be called from signal handler. It 3938 // doesn't block SIGINT et al. 3939 int os::fork_and_exec(char* cmd) { 3940 const char * argv[4] = {"sh", "-c", cmd, NULL}; 3941 3942 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 3943 // pthread_atfork handlers and reset pthread library. All we need is a 3944 // separate process to execve. Make a direct syscall to fork process. 3945 // On IA64 there's no fork syscall, we have to use fork() and hope for 3946 // the best... 3947 pid_t pid = fork(); 3948 3949 if (pid < 0) { 3950 // fork failed 3951 return -1; 3952 3953 } else if (pid == 0) { 3954 // child process 3955 3956 // execve() in BsdThreads will call pthread_kill_other_threads_np() 3957 // first to kill every thread on the thread list. Because this list is 3958 // not reset by fork() (see notes above), execve() will instead kill 3959 // every thread in the parent process. We know this is the only thread 3960 // in the new process, so make a system call directly. 3961 // IA64 should use normal execve() from glibc to match the glibc fork() 3962 // above. 3963 execve("/bin/sh", (char* const*)argv, environ); 3964 3965 // execve failed 3966 _exit(-1); 3967 3968 } else { 3969 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 3970 // care about the actual exit code, for now. 3971 3972 int status; 3973 3974 // Wait for the child process to exit. This returns immediately if 3975 // the child has already exited. */ 3976 while (waitpid(pid, &status, 0) < 0) { 3977 switch (errno) { 3978 case ECHILD: return 0; 3979 case EINTR: break; 3980 default: return -1; 3981 } 3982 } 3983 3984 if (WIFEXITED(status)) { 3985 // The child exited normally; get its exit code. 3986 return WEXITSTATUS(status); 3987 } else if (WIFSIGNALED(status)) { 3988 // The child exited because of a signal 3989 // The best value to return is 0x80 + signal number, 3990 // because that is what all Unix shells do, and because 3991 // it allows callers to distinguish between process exit and 3992 // process death by signal. 3993 return 0x80 + WTERMSIG(status); 3994 } else { 3995 // Unknown exit code; pass it through 3996 return status; 3997 } 3998 } 3999 } 4000 4001 // is_headless_jre() 4002 // 4003 // Test for the existence of xawt/libmawt.so or libawt_xawt.so 4004 // in order to report if we are running in a headless jre 4005 // 4006 // Since JDK8 xawt/libmawt.so was moved into the same directory 4007 // as libawt.so, and renamed libawt_xawt.so 4008 // 4009 bool os::is_headless_jre() { 4010 #ifdef __APPLE__ 4011 // We no longer build headless-only on Mac OS X 4012 return false; 4013 #else 4014 struct stat statbuf; 4015 char buf[MAXPATHLEN]; 4016 char libmawtpath[MAXPATHLEN]; 4017 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4018 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4019 char *p; 4020 4021 // Get path to libjvm.so 4022 os::jvm_path(buf, sizeof(buf)); 4023 4024 // Get rid of libjvm.so 4025 p = strrchr(buf, '/'); 4026 if (p == NULL) { 4027 return false; 4028 } else { 4029 *p = '\0'; 4030 } 4031 4032 // Get rid of client or server 4033 p = strrchr(buf, '/'); 4034 if (p == NULL) { 4035 return false; 4036 } else { 4037 *p = '\0'; 4038 } 4039 4040 // check xawt/libmawt.so 4041 strcpy(libmawtpath, buf); 4042 strcat(libmawtpath, xawtstr); 4043 if (::stat(libmawtpath, &statbuf) == 0) return false; 4044 4045 // check libawt_xawt.so 4046 strcpy(libmawtpath, buf); 4047 strcat(libmawtpath, new_xawtstr); 4048 if (::stat(libmawtpath, &statbuf) == 0) return false; 4049 4050 return true; 4051 #endif 4052 } 4053 4054 // Get the default path to the core file 4055 // Returns the length of the string 4056 int os::get_core_path(char* buffer, size_t bufferSize) { 4057 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 4058 4059 // Truncate if theoretical string was longer than bufferSize 4060 n = MIN2(n, (int)bufferSize); 4061 4062 return n; 4063 } 4064 4065 #ifndef PRODUCT 4066 void TestReserveMemorySpecial_test() { 4067 // No tests available for this platform 4068 } 4069 #endif 4070 4071 bool os::start_debugging(char *buf, int buflen) { 4072 int len = (int)strlen(buf); 4073 char *p = &buf[len]; 4074 4075 jio_snprintf(p, buflen-len, 4076 "\n\n" 4077 "Do you want to debug the problem?\n\n" 4078 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n" 4079 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n" 4080 "Otherwise, press RETURN to abort...", 4081 os::current_process_id(), os::current_process_id(), 4082 os::current_thread_id(), os::current_thread_id()); 4083 4084 bool yes = os::message_box("Unexpected Error", buf); 4085 4086 if (yes) { 4087 // yes, user asked VM to launch debugger 4088 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d", 4089 os::current_process_id(), os::current_process_id()); 4090 4091 os::fork_and_exec(buf); 4092 yes = false; 4093 } 4094 return yes; 4095 }