1 /* 2 * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "jvm.h" 27 #include "classfile/classLoader.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/icBuffer.hpp" 31 #include "code/vtableStubs.hpp" 32 #include "compiler/compileBroker.hpp" 33 #include "compiler/disassembler.hpp" 34 #include "interpreter/interpreter.hpp" 35 #include "logging/log.hpp" 36 #include "memory/allocation.inline.hpp" 37 #include "memory/filemap.hpp" 38 #include "oops/oop.inline.hpp" 39 #include "os_bsd.inline.hpp" 40 #include "os_share_bsd.hpp" 41 #include "prims/jniFastGetField.hpp" 42 #include "prims/jvm_misc.hpp" 43 #include "runtime/arguments.hpp" 44 #include "runtime/atomic.hpp" 45 #include "runtime/extendedPC.hpp" 46 #include "runtime/globals.hpp" 47 #include "runtime/interfaceSupport.inline.hpp" 48 #include "runtime/java.hpp" 49 #include "runtime/javaCalls.hpp" 50 #include "runtime/mutexLocker.hpp" 51 #include "runtime/objectMonitor.hpp" 52 #include "runtime/orderAccess.inline.hpp" 53 #include "runtime/osThread.hpp" 54 #include "runtime/perfMemory.hpp" 55 #include "runtime/semaphore.hpp" 56 #include "runtime/sharedRuntime.hpp" 57 #include "runtime/statSampler.hpp" 58 #include "runtime/stubRoutines.hpp" 59 #include "runtime/thread.inline.hpp" 60 #include "runtime/threadCritical.hpp" 61 #include "runtime/timer.hpp" 62 #include "services/attachListener.hpp" 63 #include "services/memTracker.hpp" 64 #include "services/runtimeService.hpp" 65 #include "utilities/align.hpp" 66 #include "utilities/decoder.hpp" 67 #include "utilities/defaultStream.hpp" 68 #include "utilities/events.hpp" 69 #include "utilities/growableArray.hpp" 70 #include "utilities/vmError.hpp" 71 72 // put OS-includes here 73 # include <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 <fcntl.h> 95 # include <string.h> 96 # include <sys/param.h> 97 # include <sys/sysctl.h> 98 # include <sys/ipc.h> 99 # include <sys/shm.h> 100 #ifndef __APPLE__ 101 # include <link.h> 102 #endif 103 # include <stdint.h> 104 # include <inttypes.h> 105 # include <sys/ioctl.h> 106 # include <sys/syscall.h> 107 108 #if defined(__FreeBSD__) || defined(__NetBSD__) 109 #include <elf.h> 110 #endif 111 112 #ifdef __APPLE__ 113 #include <mach/mach.h> // semaphore_* API 114 #include <mach-o/dyld.h> 115 #include <sys/proc_info.h> 116 #include <objc/objc-auto.h> 117 #endif 118 119 #ifndef MAP_ANONYMOUS 120 #define MAP_ANONYMOUS MAP_ANON 121 #endif 122 123 #define MAX_PATH (2 * K) 124 125 // for timer info max values which include all bits 126 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 127 128 #define LARGEPAGES_BIT (1 << 6) 129 130 //////////////////////////////////////////////////////////////////////////////// 131 // global variables 132 julong os::Bsd::_physical_memory = 0; 133 134 #ifdef __APPLE__ 135 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 136 volatile uint64_t os::Bsd::_max_abstime = 0; 137 #else 138 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 139 #endif 140 pthread_t os::Bsd::_main_thread; 141 int os::Bsd::_page_size = -1; 142 143 static jlong initial_time_count=0; 144 145 static int clock_tics_per_sec = 100; 146 147 // For diagnostics to print a message once. see run_periodic_checks 148 static sigset_t check_signal_done; 149 static bool check_signals = true; 150 151 static pid_t _initial_pid = 0; 152 153 // Signal number used to suspend/resume a thread 154 155 // do not use any signal number less than SIGSEGV, see 4355769 156 static int SR_signum = SIGUSR2; 157 sigset_t SR_sigset; 158 159 160 //////////////////////////////////////////////////////////////////////////////// 161 // utility functions 162 163 static int SR_initialize(); 164 165 julong os::available_memory() { 166 return Bsd::available_memory(); 167 } 168 169 // available here means free 170 julong os::Bsd::available_memory() { 171 uint64_t available = physical_memory() >> 2; 172 #ifdef __APPLE__ 173 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 174 vm_statistics64_data_t vmstat; 175 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 176 (host_info64_t)&vmstat, &count); 177 assert(kerr == KERN_SUCCESS, 178 "host_statistics64 failed - check mach_host_self() and count"); 179 if (kerr == KERN_SUCCESS) { 180 available = vmstat.free_count * os::vm_page_size(); 181 } 182 #endif 183 return available; 184 } 185 186 julong os::physical_memory() { 187 return Bsd::physical_memory(); 188 } 189 190 // Return true if user is running as root. 191 192 bool os::have_special_privileges() { 193 static bool init = false; 194 static bool privileges = false; 195 if (!init) { 196 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 197 init = true; 198 } 199 return privileges; 200 } 201 202 203 204 // Cpu architecture string 205 #if defined(ZERO) 206 static char cpu_arch[] = ZERO_LIBARCH; 207 #elif defined(IA64) 208 static char cpu_arch[] = "ia64"; 209 #elif defined(IA32) 210 static char cpu_arch[] = "i386"; 211 #elif defined(AMD64) 212 static char cpu_arch[] = "amd64"; 213 #elif defined(ARM) 214 static char cpu_arch[] = "arm"; 215 #elif defined(PPC32) 216 static char cpu_arch[] = "ppc"; 217 #elif defined(SPARC) 218 #ifdef _LP64 219 static char cpu_arch[] = "sparcv9"; 220 #else 221 static char cpu_arch[] = "sparc"; 222 #endif 223 #else 224 #error Add appropriate cpu_arch setting 225 #endif 226 227 // Compiler variant 228 #ifdef COMPILER2 229 #define COMPILER_VARIANT "server" 230 #else 231 #define COMPILER_VARIANT "client" 232 #endif 233 234 235 void os::Bsd::initialize_system_info() { 236 int mib[2]; 237 size_t len; 238 int cpu_val; 239 julong mem_val; 240 241 // get processors count via hw.ncpus sysctl 242 mib[0] = CTL_HW; 243 mib[1] = HW_NCPU; 244 len = sizeof(cpu_val); 245 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 246 assert(len == sizeof(cpu_val), "unexpected data size"); 247 set_processor_count(cpu_val); 248 } else { 249 set_processor_count(1); // fallback 250 } 251 252 // get physical memory via hw.memsize sysctl (hw.memsize is used 253 // since it returns a 64 bit value) 254 mib[0] = CTL_HW; 255 256 #if defined (HW_MEMSIZE) // Apple 257 mib[1] = HW_MEMSIZE; 258 #elif defined(HW_PHYSMEM) // Most of BSD 259 mib[1] = HW_PHYSMEM; 260 #elif defined(HW_REALMEM) // Old FreeBSD 261 mib[1] = HW_REALMEM; 262 #else 263 #error No ways to get physmem 264 #endif 265 266 len = sizeof(mem_val); 267 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 268 assert(len == sizeof(mem_val), "unexpected data size"); 269 _physical_memory = mem_val; 270 } else { 271 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 272 } 273 274 #ifdef __OpenBSD__ 275 { 276 // limit _physical_memory memory view on OpenBSD since 277 // datasize rlimit restricts us anyway. 278 struct rlimit limits; 279 getrlimit(RLIMIT_DATA, &limits); 280 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 281 } 282 #endif 283 } 284 285 #ifdef __APPLE__ 286 static const char *get_home() { 287 const char *home_dir = ::getenv("HOME"); 288 if ((home_dir == NULL) || (*home_dir == '\0')) { 289 struct passwd *passwd_info = getpwuid(geteuid()); 290 if (passwd_info != NULL) { 291 home_dir = passwd_info->pw_dir; 292 } 293 } 294 295 return home_dir; 296 } 297 #endif 298 299 void os::init_system_properties_values() { 300 // The next steps are taken in the product version: 301 // 302 // Obtain the JAVA_HOME value from the location of libjvm.so. 303 // This library should be located at: 304 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 305 // 306 // If "/jre/lib/" appears at the right place in the path, then we 307 // assume libjvm.so is installed in a JDK and we use this path. 308 // 309 // Otherwise exit with message: "Could not create the Java virtual machine." 310 // 311 // The following extra steps are taken in the debugging version: 312 // 313 // If "/jre/lib/" does NOT appear at the right place in the path 314 // instead of exit check for $JAVA_HOME environment variable. 315 // 316 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 317 // then we append a fake suffix "hotspot/libjvm.so" to this path so 318 // it looks like libjvm.so is installed there 319 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 320 // 321 // Otherwise exit. 322 // 323 // Important note: if the location of libjvm.so changes this 324 // code needs to be changed accordingly. 325 326 // See ld(1): 327 // The linker uses the following search paths to locate required 328 // shared libraries: 329 // 1: ... 330 // ... 331 // 7: The default directories, normally /lib and /usr/lib. 332 #ifndef DEFAULT_LIBPATH 333 #define DEFAULT_LIBPATH "/lib:/usr/lib" 334 #endif 335 336 // Base path of extensions installed on the system. 337 #define SYS_EXT_DIR "/usr/java/packages" 338 #define EXTENSIONS_DIR "/lib/ext" 339 340 #ifndef __APPLE__ 341 342 // Buffer that fits several sprintfs. 343 // Note that the space for the colon and the trailing null are provided 344 // by the nulls included by the sizeof operator. 345 const size_t bufsize = 346 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 347 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 348 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 349 350 // sysclasspath, java_home, dll_dir 351 { 352 char *pslash; 353 os::jvm_path(buf, bufsize); 354 355 // Found the full path to libjvm.so. 356 // Now cut the path to <java_home>/jre if we can. 357 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 358 pslash = strrchr(buf, '/'); 359 if (pslash != NULL) { 360 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 361 } 362 Arguments::set_dll_dir(buf); 363 364 if (pslash != NULL) { 365 pslash = strrchr(buf, '/'); 366 if (pslash != NULL) { 367 *pslash = '\0'; // Get rid of /<arch>. 368 pslash = strrchr(buf, '/'); 369 if (pslash != NULL) { 370 *pslash = '\0'; // Get rid of /lib. 371 } 372 } 373 } 374 Arguments::set_java_home(buf); 375 set_boot_path('/', ':'); 376 } 377 378 // Where to look for native libraries. 379 // 380 // Note: Due to a legacy implementation, most of the library path 381 // is set in the launcher. This was to accomodate linking restrictions 382 // on legacy Bsd implementations (which are no longer supported). 383 // Eventually, all the library path setting will be done here. 384 // 385 // However, to prevent the proliferation of improperly built native 386 // libraries, the new path component /usr/java/packages is added here. 387 // Eventually, all the library path setting will be done here. 388 { 389 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 390 // should always exist (until the legacy problem cited above is 391 // addressed). 392 const char *v = ::getenv("LD_LIBRARY_PATH"); 393 const char *v_colon = ":"; 394 if (v == NULL) { v = ""; v_colon = ""; } 395 // That's +1 for the colon and +1 for the trailing '\0'. 396 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 397 strlen(v) + 1 + 398 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 399 mtInternal); 400 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 401 Arguments::set_library_path(ld_library_path); 402 FREE_C_HEAP_ARRAY(char, ld_library_path); 403 } 404 405 // Extensions directories. 406 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 407 Arguments::set_ext_dirs(buf); 408 409 FREE_C_HEAP_ARRAY(char, buf); 410 411 #else // __APPLE__ 412 413 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 414 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 415 416 const char *user_home_dir = get_home(); 417 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 418 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 419 sizeof(SYS_EXTENSIONS_DIRS); 420 421 // Buffer that fits several sprintfs. 422 // Note that the space for the colon and the trailing null are provided 423 // by the nulls included by the sizeof operator. 424 const size_t bufsize = 425 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 426 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 427 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 428 429 // sysclasspath, java_home, dll_dir 430 { 431 char *pslash; 432 os::jvm_path(buf, bufsize); 433 434 // Found the full path to libjvm.so. 435 // Now cut the path to <java_home>/jre if we can. 436 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 437 pslash = strrchr(buf, '/'); 438 if (pslash != NULL) { 439 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 440 } 441 #ifdef STATIC_BUILD 442 strcat(buf, "/lib"); 443 #endif 444 445 Arguments::set_dll_dir(buf); 446 447 if (pslash != NULL) { 448 pslash = strrchr(buf, '/'); 449 if (pslash != NULL) { 450 *pslash = '\0'; // Get rid of /lib. 451 } 452 } 453 Arguments::set_java_home(buf); 454 set_boot_path('/', ':'); 455 } 456 457 // Where to look for native libraries. 458 // 459 // Note: Due to a legacy implementation, most of the library path 460 // is set in the launcher. This was to accomodate linking restrictions 461 // on legacy Bsd implementations (which are no longer supported). 462 // Eventually, all the library path setting will be done here. 463 // 464 // However, to prevent the proliferation of improperly built native 465 // libraries, the new path component /usr/java/packages is added here. 466 // Eventually, all the library path setting will be done here. 467 { 468 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 469 // should always exist (until the legacy problem cited above is 470 // addressed). 471 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 472 // can specify a directory inside an app wrapper 473 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 474 const char *l_colon = ":"; 475 if (l == NULL) { l = ""; l_colon = ""; } 476 477 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 478 const char *v_colon = ":"; 479 if (v == NULL) { v = ""; v_colon = ""; } 480 481 // Apple's Java6 has "." at the beginning of java.library.path. 482 // OpenJDK on Windows has "." at the end of java.library.path. 483 // OpenJDK on Linux and Solaris don't have "." in java.library.path 484 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 485 // "." is appended to the end of java.library.path. Yes, this 486 // could cause a change in behavior, but Apple's Java6 behavior 487 // can be achieved by putting "." at the beginning of the 488 // JAVA_LIBRARY_PATH environment variable. 489 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 490 strlen(v) + 1 + strlen(l) + 1 + 491 system_ext_size + 3, 492 mtInternal); 493 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 494 v, v_colon, l, l_colon, user_home_dir); 495 Arguments::set_library_path(ld_library_path); 496 FREE_C_HEAP_ARRAY(char, ld_library_path); 497 } 498 499 // Extensions directories. 500 // 501 // Note that the space for the colon and the trailing null are provided 502 // by the nulls included by the sizeof operator (so actually one byte more 503 // than necessary is allocated). 504 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 505 user_home_dir, Arguments::get_java_home()); 506 Arguments::set_ext_dirs(buf); 507 508 FREE_C_HEAP_ARRAY(char, buf); 509 510 #undef SYS_EXTENSIONS_DIR 511 #undef SYS_EXTENSIONS_DIRS 512 513 #endif // __APPLE__ 514 515 #undef SYS_EXT_DIR 516 #undef EXTENSIONS_DIR 517 } 518 519 //////////////////////////////////////////////////////////////////////////////// 520 // breakpoint support 521 522 void os::breakpoint() { 523 BREAKPOINT; 524 } 525 526 extern "C" void breakpoint() { 527 // use debugger to set breakpoint here 528 } 529 530 //////////////////////////////////////////////////////////////////////////////// 531 // signal support 532 533 debug_only(static bool signal_sets_initialized = false); 534 static sigset_t unblocked_sigs, vm_sigs; 535 536 bool os::Bsd::is_sig_ignored(int sig) { 537 struct sigaction oact; 538 sigaction(sig, (struct sigaction*)NULL, &oact); 539 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 540 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 541 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) { 542 return true; 543 } else { 544 return false; 545 } 546 } 547 548 void os::Bsd::signal_sets_init() { 549 // Should also have an assertion stating we are still single-threaded. 550 assert(!signal_sets_initialized, "Already initialized"); 551 // Fill in signals that are necessarily unblocked for all threads in 552 // the VM. Currently, we unblock the following signals: 553 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 554 // by -Xrs (=ReduceSignalUsage)); 555 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 556 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 557 // the dispositions or masks wrt these signals. 558 // Programs embedding the VM that want to use the above signals for their 559 // own purposes must, at this time, use the "-Xrs" option to prevent 560 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 561 // (See bug 4345157, and other related bugs). 562 // In reality, though, unblocking these signals is really a nop, since 563 // these signals are not blocked by default. 564 sigemptyset(&unblocked_sigs); 565 sigaddset(&unblocked_sigs, SIGILL); 566 sigaddset(&unblocked_sigs, SIGSEGV); 567 sigaddset(&unblocked_sigs, SIGBUS); 568 sigaddset(&unblocked_sigs, SIGFPE); 569 sigaddset(&unblocked_sigs, SR_signum); 570 571 if (!ReduceSignalUsage) { 572 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 573 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 574 575 } 576 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 577 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 578 } 579 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 580 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 581 } 582 } 583 // Fill in signals that are blocked by all but the VM thread. 584 sigemptyset(&vm_sigs); 585 if (!ReduceSignalUsage) { 586 sigaddset(&vm_sigs, BREAK_SIGNAL); 587 } 588 debug_only(signal_sets_initialized = true); 589 590 } 591 592 // These are signals that are unblocked while a thread is running Java. 593 // (For some reason, they get blocked by default.) 594 sigset_t* os::Bsd::unblocked_signals() { 595 assert(signal_sets_initialized, "Not initialized"); 596 return &unblocked_sigs; 597 } 598 599 // These are the signals that are blocked while a (non-VM) thread is 600 // running Java. Only the VM thread handles these signals. 601 sigset_t* os::Bsd::vm_signals() { 602 assert(signal_sets_initialized, "Not initialized"); 603 return &vm_sigs; 604 } 605 606 void os::Bsd::hotspot_sigmask(Thread* thread) { 607 608 //Save caller's signal mask before setting VM signal mask 609 sigset_t caller_sigmask; 610 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 611 612 OSThread* osthread = thread->osthread(); 613 osthread->set_caller_sigmask(caller_sigmask); 614 615 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 616 617 if (!ReduceSignalUsage) { 618 if (thread->is_VM_thread()) { 619 // Only the VM thread handles BREAK_SIGNAL ... 620 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 621 } else { 622 // ... all other threads block BREAK_SIGNAL 623 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 624 } 625 } 626 } 627 628 629 ////////////////////////////////////////////////////////////////////////////// 630 // create new thread 631 632 #ifdef __APPLE__ 633 // library handle for calling objc_registerThreadWithCollector() 634 // without static linking to the libobjc library 635 #define OBJC_LIB "/usr/lib/libobjc.dylib" 636 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 637 typedef void (*objc_registerThreadWithCollector_t)(); 638 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 639 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 640 #endif 641 642 #ifdef __APPLE__ 643 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 644 // Additional thread_id used to correlate threads in SA 645 thread_identifier_info_data_t m_ident_info; 646 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 647 648 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 649 (thread_info_t) &m_ident_info, &count); 650 651 return m_ident_info.thread_id; 652 } 653 #endif 654 655 // Thread start routine for all newly created threads 656 static void *thread_native_entry(Thread *thread) { 657 // Try to randomize the cache line index of hot stack frames. 658 // This helps when threads of the same stack traces evict each other's 659 // cache lines. The threads can be either from the same JVM instance, or 660 // from different JVM instances. The benefit is especially true for 661 // processors with hyperthreading technology. 662 static int counter = 0; 663 int pid = os::current_process_id(); 664 alloca(((pid ^ counter++) & 7) * 128); 665 666 thread->initialize_thread_current(); 667 668 OSThread* osthread = thread->osthread(); 669 Monitor* sync = osthread->startThread_lock(); 670 671 osthread->set_thread_id(os::Bsd::gettid()); 672 673 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 674 os::current_thread_id(), (uintx) pthread_self()); 675 676 #ifdef __APPLE__ 677 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 678 guarantee(unique_thread_id != 0, "unique thread id was not found"); 679 osthread->set_unique_thread_id(unique_thread_id); 680 #endif 681 // initialize signal mask for this thread 682 os::Bsd::hotspot_sigmask(thread); 683 684 // initialize floating point control register 685 os::Bsd::init_thread_fpu_state(); 686 687 #ifdef __APPLE__ 688 // register thread with objc gc 689 if (objc_registerThreadWithCollectorFunction != NULL) { 690 objc_registerThreadWithCollectorFunction(); 691 } 692 #endif 693 694 // handshaking with parent thread 695 { 696 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 697 698 // notify parent thread 699 osthread->set_state(INITIALIZED); 700 sync->notify_all(); 701 702 // wait until os::start_thread() 703 while (osthread->get_state() == INITIALIZED) { 704 sync->wait(Mutex::_no_safepoint_check_flag); 705 } 706 } 707 708 // call one more level start routine 709 thread->run(); 710 711 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 712 os::current_thread_id(), (uintx) pthread_self()); 713 714 // If a thread has not deleted itself ("delete this") as part of its 715 // termination sequence, we have to ensure thread-local-storage is 716 // cleared before we actually terminate. No threads should ever be 717 // deleted asynchronously with respect to their termination. 718 if (Thread::current_or_null_safe() != NULL) { 719 assert(Thread::current_or_null_safe() == thread, "current thread is wrong"); 720 thread->clear_thread_current(); 721 } 722 723 return 0; 724 } 725 726 bool os::create_thread(Thread* thread, ThreadType thr_type, 727 size_t req_stack_size) { 728 assert(thread->osthread() == NULL, "caller responsible"); 729 730 // Allocate the OSThread object 731 OSThread* osthread = new OSThread(NULL, NULL); 732 if (osthread == NULL) { 733 return false; 734 } 735 736 // set the correct thread state 737 osthread->set_thread_type(thr_type); 738 739 // Initial state is ALLOCATED but not INITIALIZED 740 osthread->set_state(ALLOCATED); 741 742 thread->set_osthread(osthread); 743 744 // init thread attributes 745 pthread_attr_t attr; 746 pthread_attr_init(&attr); 747 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 748 749 // calculate stack size if it's not specified by caller 750 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size); 751 int status = pthread_attr_setstacksize(&attr, stack_size); 752 assert_status(status == 0, status, "pthread_attr_setstacksize"); 753 754 ThreadState state; 755 756 { 757 pthread_t tid; 758 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread); 759 760 char buf[64]; 761 if (ret == 0) { 762 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ", 763 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr)); 764 } else { 765 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.", 766 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr)); 767 } 768 769 pthread_attr_destroy(&attr); 770 771 if (ret != 0) { 772 // Need to clean up stuff we've allocated so far 773 thread->set_osthread(NULL); 774 delete osthread; 775 return false; 776 } 777 778 // Store pthread info into the OSThread 779 osthread->set_pthread_id(tid); 780 781 // Wait until child thread is either initialized or aborted 782 { 783 Monitor* sync_with_child = osthread->startThread_lock(); 784 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 785 while ((state = osthread->get_state()) == ALLOCATED) { 786 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 787 } 788 } 789 790 } 791 792 // Aborted due to thread limit being reached 793 if (state == ZOMBIE) { 794 thread->set_osthread(NULL); 795 delete osthread; 796 return false; 797 } 798 799 // The thread is returned suspended (in state INITIALIZED), 800 // and is started higher up in the call chain 801 assert(state == INITIALIZED, "race condition"); 802 return true; 803 } 804 805 ///////////////////////////////////////////////////////////////////////////// 806 // attach existing thread 807 808 // bootstrap the main thread 809 bool os::create_main_thread(JavaThread* thread) { 810 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 811 return create_attached_thread(thread); 812 } 813 814 bool os::create_attached_thread(JavaThread* thread) { 815 #ifdef ASSERT 816 thread->verify_not_published(); 817 #endif 818 819 // Allocate the OSThread object 820 OSThread* osthread = new OSThread(NULL, NULL); 821 822 if (osthread == NULL) { 823 return false; 824 } 825 826 osthread->set_thread_id(os::Bsd::gettid()); 827 828 // Store pthread info into the OSThread 829 #ifdef __APPLE__ 830 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 831 guarantee(unique_thread_id != 0, "just checking"); 832 osthread->set_unique_thread_id(unique_thread_id); 833 #endif 834 osthread->set_pthread_id(::pthread_self()); 835 836 // initialize floating point control register 837 os::Bsd::init_thread_fpu_state(); 838 839 // Initial thread state is RUNNABLE 840 osthread->set_state(RUNNABLE); 841 842 thread->set_osthread(osthread); 843 844 // initialize signal mask for this thread 845 // and save the caller's signal mask 846 os::Bsd::hotspot_sigmask(thread); 847 848 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").", 849 os::current_thread_id(), (uintx) pthread_self()); 850 851 return true; 852 } 853 854 void os::pd_start_thread(Thread* thread) { 855 OSThread * osthread = thread->osthread(); 856 assert(osthread->get_state() != INITIALIZED, "just checking"); 857 Monitor* sync_with_child = osthread->startThread_lock(); 858 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 859 sync_with_child->notify(); 860 } 861 862 // Free Bsd resources related to the OSThread 863 void os::free_thread(OSThread* osthread) { 864 assert(osthread != NULL, "osthread not set"); 865 866 // We are told to free resources of the argument thread, 867 // but we can only really operate on the current thread. 868 assert(Thread::current()->osthread() == osthread, 869 "os::free_thread but not current thread"); 870 871 // Restore caller's signal mask 872 sigset_t sigmask = osthread->caller_sigmask(); 873 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 874 875 delete osthread; 876 } 877 878 //////////////////////////////////////////////////////////////////////////////// 879 // time support 880 881 // Time since start-up in seconds to a fine granularity. 882 // Used by VMSelfDestructTimer and the MemProfiler. 883 double os::elapsedTime() { 884 885 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 886 } 887 888 jlong os::elapsed_counter() { 889 return javaTimeNanos() - initial_time_count; 890 } 891 892 jlong os::elapsed_frequency() { 893 return NANOSECS_PER_SEC; // nanosecond resolution 894 } 895 896 bool os::supports_vtime() { return true; } 897 bool os::enable_vtime() { return false; } 898 bool os::vtime_enabled() { return false; } 899 900 double os::elapsedVTime() { 901 // better than nothing, but not much 902 return elapsedTime(); 903 } 904 905 jlong os::javaTimeMillis() { 906 timeval time; 907 int status = gettimeofday(&time, NULL); 908 assert(status != -1, "bsd error"); 909 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 910 } 911 912 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 913 timeval time; 914 int status = gettimeofday(&time, NULL); 915 assert(status != -1, "bsd error"); 916 seconds = jlong(time.tv_sec); 917 nanos = jlong(time.tv_usec) * 1000; 918 } 919 920 #ifndef __APPLE__ 921 #ifndef CLOCK_MONOTONIC 922 #define CLOCK_MONOTONIC (1) 923 #endif 924 #endif 925 926 #ifdef __APPLE__ 927 void os::Bsd::clock_init() { 928 mach_timebase_info(&_timebase_info); 929 } 930 #else 931 void os::Bsd::clock_init() { 932 struct timespec res; 933 struct timespec tp; 934 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 935 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 936 // yes, monotonic clock is supported 937 _clock_gettime = ::clock_gettime; 938 } 939 } 940 #endif 941 942 943 944 #ifdef __APPLE__ 945 946 jlong os::javaTimeNanos() { 947 const uint64_t tm = mach_absolute_time(); 948 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 949 const uint64_t prev = Bsd::_max_abstime; 950 if (now <= prev) { 951 return prev; // same or retrograde time; 952 } 953 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev); 954 assert(obsv >= prev, "invariant"); // Monotonicity 955 // If the CAS succeeded then we're done and return "now". 956 // If the CAS failed and the observed value "obsv" is >= now then 957 // we should return "obsv". If the CAS failed and now > obsv > prv then 958 // some other thread raced this thread and installed a new value, in which case 959 // we could either (a) retry the entire operation, (b) retry trying to install now 960 // or (c) just return obsv. We use (c). No loop is required although in some cases 961 // we might discard a higher "now" value in deference to a slightly lower but freshly 962 // installed obsv value. That's entirely benign -- it admits no new orderings compared 963 // to (a) or (b) -- and greatly reduces coherence traffic. 964 // We might also condition (c) on the magnitude of the delta between obsv and now. 965 // Avoiding excessive CAS operations to hot RW locations is critical. 966 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 967 return (prev == obsv) ? now : obsv; 968 } 969 970 #else // __APPLE__ 971 972 jlong os::javaTimeNanos() { 973 if (os::supports_monotonic_clock()) { 974 struct timespec tp; 975 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 976 assert(status == 0, "gettime error"); 977 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 978 return result; 979 } else { 980 timeval time; 981 int status = gettimeofday(&time, NULL); 982 assert(status != -1, "bsd error"); 983 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 984 return 1000 * usecs; 985 } 986 } 987 988 #endif // __APPLE__ 989 990 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 991 if (os::supports_monotonic_clock()) { 992 info_ptr->max_value = ALL_64_BITS; 993 994 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 995 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 996 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 997 } else { 998 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 999 info_ptr->max_value = ALL_64_BITS; 1000 1001 // gettimeofday is a real time clock so it skips 1002 info_ptr->may_skip_backward = true; 1003 info_ptr->may_skip_forward = true; 1004 } 1005 1006 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1007 } 1008 1009 // Return the real, user, and system times in seconds from an 1010 // arbitrary fixed point in the past. 1011 bool os::getTimesSecs(double* process_real_time, 1012 double* process_user_time, 1013 double* process_system_time) { 1014 struct tms ticks; 1015 clock_t real_ticks = times(&ticks); 1016 1017 if (real_ticks == (clock_t) (-1)) { 1018 return false; 1019 } else { 1020 double ticks_per_second = (double) clock_tics_per_sec; 1021 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1022 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1023 *process_real_time = ((double) real_ticks) / ticks_per_second; 1024 1025 return true; 1026 } 1027 } 1028 1029 1030 char * os::local_time_string(char *buf, size_t buflen) { 1031 struct tm t; 1032 time_t long_time; 1033 time(&long_time); 1034 localtime_r(&long_time, &t); 1035 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1036 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1037 t.tm_hour, t.tm_min, t.tm_sec); 1038 return buf; 1039 } 1040 1041 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1042 return localtime_r(clock, res); 1043 } 1044 1045 //////////////////////////////////////////////////////////////////////////////// 1046 // runtime exit support 1047 1048 // Note: os::shutdown() might be called very early during initialization, or 1049 // called from signal handler. Before adding something to os::shutdown(), make 1050 // sure it is async-safe and can handle partially initialized VM. 1051 void os::shutdown() { 1052 1053 // allow PerfMemory to attempt cleanup of any persistent resources 1054 perfMemory_exit(); 1055 1056 // needs to remove object in file system 1057 AttachListener::abort(); 1058 1059 // flush buffered output, finish log files 1060 ostream_abort(); 1061 1062 // Check for abort hook 1063 abort_hook_t abort_hook = Arguments::abort_hook(); 1064 if (abort_hook != NULL) { 1065 abort_hook(); 1066 } 1067 1068 } 1069 1070 // Note: os::abort() might be called very early during initialization, or 1071 // called from signal handler. Before adding something to os::abort(), make 1072 // sure it is async-safe and can handle partially initialized VM. 1073 void os::abort(bool dump_core, void* siginfo, const void* context) { 1074 os::shutdown(); 1075 if (dump_core) { 1076 #ifndef PRODUCT 1077 fdStream out(defaultStream::output_fd()); 1078 out.print_raw("Current thread is "); 1079 char buf[16]; 1080 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1081 out.print_raw_cr(buf); 1082 out.print_raw_cr("Dumping core ..."); 1083 #endif 1084 ::abort(); // dump core 1085 } 1086 1087 ::exit(1); 1088 } 1089 1090 // Die immediately, no exit hook, no abort hook, no cleanup. 1091 void os::die() { 1092 // _exit() on BsdThreads only kills current thread 1093 ::abort(); 1094 } 1095 1096 // This method is a copy of JDK's sysGetLastErrorString 1097 // from src/solaris/hpi/src/system_md.c 1098 1099 size_t os::lasterror(char *buf, size_t len) { 1100 if (errno == 0) return 0; 1101 1102 const char *s = os::strerror(errno); 1103 size_t n = ::strlen(s); 1104 if (n >= len) { 1105 n = len - 1; 1106 } 1107 ::strncpy(buf, s, n); 1108 buf[n] = '\0'; 1109 return n; 1110 } 1111 1112 // Information of current thread in variety of formats 1113 pid_t os::Bsd::gettid() { 1114 int retval = -1; 1115 1116 #ifdef __APPLE__ //XNU kernel 1117 // despite the fact mach port is actually not a thread id use it 1118 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1119 retval = ::pthread_mach_thread_np(::pthread_self()); 1120 guarantee(retval != 0, "just checking"); 1121 return retval; 1122 1123 #else 1124 #ifdef __FreeBSD__ 1125 retval = syscall(SYS_thr_self); 1126 #else 1127 #ifdef __OpenBSD__ 1128 retval = syscall(SYS_getthrid); 1129 #else 1130 #ifdef __NetBSD__ 1131 retval = (pid_t) syscall(SYS__lwp_self); 1132 #endif 1133 #endif 1134 #endif 1135 #endif 1136 1137 if (retval == -1) { 1138 return getpid(); 1139 } 1140 } 1141 1142 intx os::current_thread_id() { 1143 #ifdef __APPLE__ 1144 return (intx)::pthread_mach_thread_np(::pthread_self()); 1145 #else 1146 return (intx)::pthread_self(); 1147 #endif 1148 } 1149 1150 int os::current_process_id() { 1151 1152 // Under the old bsd thread library, bsd gives each thread 1153 // its own process id. Because of this each thread will return 1154 // a different pid if this method were to return the result 1155 // of getpid(2). Bsd provides no api that returns the pid 1156 // of the launcher thread for the vm. This implementation 1157 // returns a unique pid, the pid of the launcher thread 1158 // that starts the vm 'process'. 1159 1160 // Under the NPTL, getpid() returns the same pid as the 1161 // launcher thread rather than a unique pid per thread. 1162 // Use gettid() if you want the old pre NPTL behaviour. 1163 1164 // if you are looking for the result of a call to getpid() that 1165 // returns a unique pid for the calling thread, then look at the 1166 // OSThread::thread_id() method in osThread_bsd.hpp file 1167 1168 return (int)(_initial_pid ? _initial_pid : getpid()); 1169 } 1170 1171 // DLL functions 1172 1173 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1174 1175 // This must be hard coded because it's the system's temporary 1176 // directory not the java application's temp directory, ala java.io.tmpdir. 1177 #ifdef __APPLE__ 1178 // macosx has a secure per-user temporary directory 1179 char temp_path_storage[PATH_MAX]; 1180 const char* os::get_temp_directory() { 1181 static char *temp_path = NULL; 1182 if (temp_path == NULL) { 1183 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1184 if (pathSize == 0 || pathSize > PATH_MAX) { 1185 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1186 } 1187 temp_path = temp_path_storage; 1188 } 1189 return temp_path; 1190 } 1191 #else // __APPLE__ 1192 const char* os::get_temp_directory() { return "/tmp"; } 1193 #endif // __APPLE__ 1194 1195 // check if addr is inside libjvm.so 1196 bool os::address_is_in_vm(address addr) { 1197 static address libjvm_base_addr; 1198 Dl_info dlinfo; 1199 1200 if (libjvm_base_addr == NULL) { 1201 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1202 libjvm_base_addr = (address)dlinfo.dli_fbase; 1203 } 1204 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1205 } 1206 1207 if (dladdr((void *)addr, &dlinfo) != 0) { 1208 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1209 } 1210 1211 return false; 1212 } 1213 1214 1215 #define MACH_MAXSYMLEN 256 1216 1217 bool os::dll_address_to_function_name(address addr, char *buf, 1218 int buflen, int *offset, 1219 bool demangle) { 1220 // buf is not optional, but offset is optional 1221 assert(buf != NULL, "sanity check"); 1222 1223 Dl_info dlinfo; 1224 char localbuf[MACH_MAXSYMLEN]; 1225 1226 if (dladdr((void*)addr, &dlinfo) != 0) { 1227 // see if we have a matching symbol 1228 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1229 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) { 1230 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1231 } 1232 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1233 return true; 1234 } 1235 // no matching symbol so try for just file info 1236 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1237 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1238 buf, buflen, offset, dlinfo.dli_fname, demangle)) { 1239 return true; 1240 } 1241 } 1242 1243 // Handle non-dynamic manually: 1244 if (dlinfo.dli_fbase != NULL && 1245 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1246 dlinfo.dli_fbase)) { 1247 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) { 1248 jio_snprintf(buf, buflen, "%s", localbuf); 1249 } 1250 return true; 1251 } 1252 } 1253 buf[0] = '\0'; 1254 if (offset != NULL) *offset = -1; 1255 return false; 1256 } 1257 1258 // ported from solaris version 1259 bool os::dll_address_to_library_name(address addr, char* buf, 1260 int buflen, int* offset) { 1261 // buf is not optional, but offset is optional 1262 assert(buf != NULL, "sanity check"); 1263 1264 Dl_info dlinfo; 1265 1266 if (dladdr((void*)addr, &dlinfo) != 0) { 1267 if (dlinfo.dli_fname != NULL) { 1268 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1269 } 1270 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1271 *offset = addr - (address)dlinfo.dli_fbase; 1272 } 1273 return true; 1274 } 1275 1276 buf[0] = '\0'; 1277 if (offset) *offset = -1; 1278 return false; 1279 } 1280 1281 // Loads .dll/.so and 1282 // in case of error it checks if .dll/.so was built for the 1283 // same architecture as Hotspot is running on 1284 1285 #ifdef __APPLE__ 1286 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1287 #ifdef STATIC_BUILD 1288 return os::get_default_process_handle(); 1289 #else 1290 void * result= ::dlopen(filename, RTLD_LAZY); 1291 if (result != NULL) { 1292 // Successful loading 1293 return result; 1294 } 1295 1296 // Read system error message into ebuf 1297 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1298 ebuf[ebuflen-1]='\0'; 1299 1300 return NULL; 1301 #endif // STATIC_BUILD 1302 } 1303 #else 1304 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1305 #ifdef STATIC_BUILD 1306 return os::get_default_process_handle(); 1307 #else 1308 void * result= ::dlopen(filename, RTLD_LAZY); 1309 if (result != NULL) { 1310 // Successful loading 1311 return result; 1312 } 1313 1314 Elf32_Ehdr elf_head; 1315 1316 // Read system error message into ebuf 1317 // It may or may not be overwritten below 1318 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1319 ebuf[ebuflen-1]='\0'; 1320 int diag_msg_max_length=ebuflen-strlen(ebuf); 1321 char* diag_msg_buf=ebuf+strlen(ebuf); 1322 1323 if (diag_msg_max_length==0) { 1324 // No more space in ebuf for additional diagnostics message 1325 return NULL; 1326 } 1327 1328 1329 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1330 1331 if (file_descriptor < 0) { 1332 // Can't open library, report dlerror() message 1333 return NULL; 1334 } 1335 1336 bool failed_to_read_elf_head= 1337 (sizeof(elf_head)!= 1338 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1339 1340 ::close(file_descriptor); 1341 if (failed_to_read_elf_head) { 1342 // file i/o error - report dlerror() msg 1343 return NULL; 1344 } 1345 1346 typedef struct { 1347 Elf32_Half code; // Actual value as defined in elf.h 1348 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1349 char elf_class; // 32 or 64 bit 1350 char endianess; // MSB or LSB 1351 char* name; // String representation 1352 } arch_t; 1353 1354 #ifndef EM_486 1355 #define EM_486 6 /* Intel 80486 */ 1356 #endif 1357 1358 #ifndef EM_MIPS_RS3_LE 1359 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1360 #endif 1361 1362 #ifndef EM_PPC64 1363 #define EM_PPC64 21 /* PowerPC64 */ 1364 #endif 1365 1366 #ifndef EM_S390 1367 #define EM_S390 22 /* IBM System/390 */ 1368 #endif 1369 1370 #ifndef EM_IA_64 1371 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1372 #endif 1373 1374 #ifndef EM_X86_64 1375 #define EM_X86_64 62 /* AMD x86-64 */ 1376 #endif 1377 1378 static const arch_t arch_array[]={ 1379 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1380 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1381 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1382 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1383 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1384 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1385 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1386 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1387 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1388 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1389 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1390 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1391 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1392 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1393 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1394 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1395 }; 1396 1397 #if (defined IA32) 1398 static Elf32_Half running_arch_code=EM_386; 1399 #elif (defined AMD64) 1400 static Elf32_Half running_arch_code=EM_X86_64; 1401 #elif (defined IA64) 1402 static Elf32_Half running_arch_code=EM_IA_64; 1403 #elif (defined __sparc) && (defined _LP64) 1404 static Elf32_Half running_arch_code=EM_SPARCV9; 1405 #elif (defined __sparc) && (!defined _LP64) 1406 static Elf32_Half running_arch_code=EM_SPARC; 1407 #elif (defined __powerpc64__) 1408 static Elf32_Half running_arch_code=EM_PPC64; 1409 #elif (defined __powerpc__) 1410 static Elf32_Half running_arch_code=EM_PPC; 1411 #elif (defined ARM) 1412 static Elf32_Half running_arch_code=EM_ARM; 1413 #elif (defined S390) 1414 static Elf32_Half running_arch_code=EM_S390; 1415 #elif (defined ALPHA) 1416 static Elf32_Half running_arch_code=EM_ALPHA; 1417 #elif (defined MIPSEL) 1418 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1419 #elif (defined PARISC) 1420 static Elf32_Half running_arch_code=EM_PARISC; 1421 #elif (defined MIPS) 1422 static Elf32_Half running_arch_code=EM_MIPS; 1423 #elif (defined M68K) 1424 static Elf32_Half running_arch_code=EM_68K; 1425 #else 1426 #error Method os::dll_load requires that one of following is defined:\ 1427 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1428 #endif 1429 1430 // Identify compatability class for VM's architecture and library's architecture 1431 // Obtain string descriptions for architectures 1432 1433 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1434 int running_arch_index=-1; 1435 1436 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1437 if (running_arch_code == arch_array[i].code) { 1438 running_arch_index = i; 1439 } 1440 if (lib_arch.code == arch_array[i].code) { 1441 lib_arch.compat_class = arch_array[i].compat_class; 1442 lib_arch.name = arch_array[i].name; 1443 } 1444 } 1445 1446 assert(running_arch_index != -1, 1447 "Didn't find running architecture code (running_arch_code) in arch_array"); 1448 if (running_arch_index == -1) { 1449 // Even though running architecture detection failed 1450 // we may still continue with reporting dlerror() message 1451 return NULL; 1452 } 1453 1454 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1455 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1456 return NULL; 1457 } 1458 1459 #ifndef S390 1460 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1461 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1462 return NULL; 1463 } 1464 #endif // !S390 1465 1466 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1467 if (lib_arch.name!=NULL) { 1468 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1469 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1470 lib_arch.name, arch_array[running_arch_index].name); 1471 } else { 1472 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1473 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1474 lib_arch.code, 1475 arch_array[running_arch_index].name); 1476 } 1477 } 1478 1479 return NULL; 1480 #endif // STATIC_BUILD 1481 } 1482 #endif // !__APPLE__ 1483 1484 void* os::get_default_process_handle() { 1485 #ifdef __APPLE__ 1486 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1487 // to avoid finding unexpected symbols on second (or later) 1488 // loads of a library. 1489 return (void*)::dlopen(NULL, RTLD_FIRST); 1490 #else 1491 return (void*)::dlopen(NULL, RTLD_LAZY); 1492 #endif 1493 } 1494 1495 // XXX: Do we need a lock around this as per Linux? 1496 void* os::dll_lookup(void* handle, const char* name) { 1497 return dlsym(handle, name); 1498 } 1499 1500 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1501 outputStream * out = (outputStream *) param; 1502 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name); 1503 return 0; 1504 } 1505 1506 void os::print_dll_info(outputStream *st) { 1507 st->print_cr("Dynamic libraries:"); 1508 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1509 st->print_cr("Error: Cannot print dynamic libraries."); 1510 } 1511 } 1512 1513 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1514 #ifdef RTLD_DI_LINKMAP 1515 Dl_info dli; 1516 void *handle; 1517 Link_map *map; 1518 Link_map *p; 1519 1520 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1521 dli.dli_fname == NULL) { 1522 return 1; 1523 } 1524 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1525 if (handle == NULL) { 1526 return 1; 1527 } 1528 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1529 if (map == NULL) { 1530 dlclose(handle); 1531 return 1; 1532 } 1533 1534 while (map->l_prev != NULL) 1535 map = map->l_prev; 1536 1537 while (map != NULL) { 1538 // Value for top_address is returned as 0 since we don't have any information about module size 1539 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1540 dlclose(handle); 1541 return 1; 1542 } 1543 map = map->l_next; 1544 } 1545 1546 dlclose(handle); 1547 #elif defined(__APPLE__) 1548 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1549 // Value for top_address is returned as 0 since we don't have any information about module size 1550 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1551 return 1; 1552 } 1553 } 1554 return 0; 1555 #else 1556 return 1; 1557 #endif 1558 } 1559 1560 void os::get_summary_os_info(char* buf, size_t buflen) { 1561 // These buffers are small because we want this to be brief 1562 // and not use a lot of stack while generating the hs_err file. 1563 char os[100]; 1564 size_t size = sizeof(os); 1565 int mib_kern[] = { CTL_KERN, KERN_OSTYPE }; 1566 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) { 1567 #ifdef __APPLE__ 1568 strncpy(os, "Darwin", sizeof(os)); 1569 #elif __OpenBSD__ 1570 strncpy(os, "OpenBSD", sizeof(os)); 1571 #else 1572 strncpy(os, "BSD", sizeof(os)); 1573 #endif 1574 } 1575 1576 char release[100]; 1577 size = sizeof(release); 1578 int mib_release[] = { CTL_KERN, KERN_OSRELEASE }; 1579 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) { 1580 // if error, leave blank 1581 strncpy(release, "", sizeof(release)); 1582 } 1583 snprintf(buf, buflen, "%s %s", os, release); 1584 } 1585 1586 void os::print_os_info_brief(outputStream* st) { 1587 os::Posix::print_uname_info(st); 1588 } 1589 1590 void os::print_os_info(outputStream* st) { 1591 st->print("OS:"); 1592 1593 os::Posix::print_uname_info(st); 1594 1595 os::Posix::print_rlimit_info(st); 1596 1597 os::Posix::print_load_average(st); 1598 } 1599 1600 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) { 1601 // Nothing to do for now. 1602 } 1603 1604 void os::get_summary_cpu_info(char* buf, size_t buflen) { 1605 unsigned int mhz; 1606 size_t size = sizeof(mhz); 1607 int mib[] = { CTL_HW, HW_CPU_FREQ }; 1608 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) { 1609 mhz = 1; // looks like an error but can be divided by 1610 } else { 1611 mhz /= 1000000; // reported in millions 1612 } 1613 1614 char model[100]; 1615 size = sizeof(model); 1616 int mib_model[] = { CTL_HW, HW_MODEL }; 1617 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) { 1618 strncpy(model, cpu_arch, sizeof(model)); 1619 } 1620 1621 char machine[100]; 1622 size = sizeof(machine); 1623 int mib_machine[] = { CTL_HW, HW_MACHINE }; 1624 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) { 1625 strncpy(machine, "", sizeof(machine)); 1626 } 1627 1628 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz); 1629 } 1630 1631 void os::print_memory_info(outputStream* st) { 1632 1633 st->print("Memory:"); 1634 st->print(" %dk page", os::vm_page_size()>>10); 1635 1636 st->print(", physical " UINT64_FORMAT "k", 1637 os::physical_memory() >> 10); 1638 st->print("(" UINT64_FORMAT "k free)", 1639 os::available_memory() >> 10); 1640 st->cr(); 1641 } 1642 1643 static void print_signal_handler(outputStream* st, int sig, 1644 char* buf, size_t buflen); 1645 1646 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1647 st->print_cr("Signal Handlers:"); 1648 print_signal_handler(st, SIGSEGV, buf, buflen); 1649 print_signal_handler(st, SIGBUS , buf, buflen); 1650 print_signal_handler(st, SIGFPE , buf, buflen); 1651 print_signal_handler(st, SIGPIPE, buf, buflen); 1652 print_signal_handler(st, SIGXFSZ, buf, buflen); 1653 print_signal_handler(st, SIGILL , buf, buflen); 1654 print_signal_handler(st, SR_signum, buf, buflen); 1655 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1656 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1657 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1658 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1659 } 1660 1661 static char saved_jvm_path[MAXPATHLEN] = {0}; 1662 1663 // Find the full path to the current module, libjvm 1664 void os::jvm_path(char *buf, jint buflen) { 1665 // Error checking. 1666 if (buflen < MAXPATHLEN) { 1667 assert(false, "must use a large-enough buffer"); 1668 buf[0] = '\0'; 1669 return; 1670 } 1671 // Lazy resolve the path to current module. 1672 if (saved_jvm_path[0] != 0) { 1673 strcpy(buf, saved_jvm_path); 1674 return; 1675 } 1676 1677 char dli_fname[MAXPATHLEN]; 1678 bool ret = dll_address_to_library_name( 1679 CAST_FROM_FN_PTR(address, os::jvm_path), 1680 dli_fname, sizeof(dli_fname), NULL); 1681 assert(ret, "cannot locate libjvm"); 1682 char *rp = NULL; 1683 if (ret && dli_fname[0] != '\0') { 1684 rp = os::Posix::realpath(dli_fname, buf, buflen); 1685 } 1686 if (rp == NULL) { 1687 return; 1688 } 1689 1690 if (Arguments::sun_java_launcher_is_altjvm()) { 1691 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1692 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1693 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1694 // appears at the right place in the string, then assume we are 1695 // installed in a JDK and we're done. Otherwise, check for a 1696 // JAVA_HOME environment variable and construct a path to the JVM 1697 // being overridden. 1698 1699 const char *p = buf + strlen(buf) - 1; 1700 for (int count = 0; p > buf && count < 5; ++count) { 1701 for (--p; p > buf && *p != '/'; --p) 1702 /* empty */ ; 1703 } 1704 1705 if (strncmp(p, "/jre/lib/", 9) != 0) { 1706 // Look for JAVA_HOME in the environment. 1707 char* java_home_var = ::getenv("JAVA_HOME"); 1708 if (java_home_var != NULL && java_home_var[0] != 0) { 1709 char* jrelib_p; 1710 int len; 1711 1712 // Check the current module name "libjvm" 1713 p = strrchr(buf, '/'); 1714 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1715 1716 rp = os::Posix::realpath(java_home_var, buf, buflen); 1717 if (rp == NULL) { 1718 return; 1719 } 1720 1721 // determine if this is a legacy image or modules image 1722 // modules image doesn't have "jre" subdirectory 1723 len = strlen(buf); 1724 assert(len < buflen, "Ran out of buffer space"); 1725 jrelib_p = buf + len; 1726 1727 // Add the appropriate library subdir 1728 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1729 if (0 != access(buf, F_OK)) { 1730 snprintf(jrelib_p, buflen-len, "/lib"); 1731 } 1732 1733 // Add the appropriate client or server subdir 1734 len = strlen(buf); 1735 jrelib_p = buf + len; 1736 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1737 if (0 != access(buf, F_OK)) { 1738 snprintf(jrelib_p, buflen-len, "%s", ""); 1739 } 1740 1741 // If the path exists within JAVA_HOME, add the JVM library name 1742 // to complete the path to JVM being overridden. Otherwise fallback 1743 // to the path to the current library. 1744 if (0 == access(buf, F_OK)) { 1745 // Use current module name "libjvm" 1746 len = strlen(buf); 1747 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1748 } else { 1749 // Fall back to path of current library 1750 rp = os::Posix::realpath(dli_fname, buf, buflen); 1751 if (rp == NULL) { 1752 return; 1753 } 1754 } 1755 } 1756 } 1757 } 1758 1759 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1760 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1761 } 1762 1763 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1764 // no prefix required, not even "_" 1765 } 1766 1767 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1768 // no suffix required 1769 } 1770 1771 //////////////////////////////////////////////////////////////////////////////// 1772 // sun.misc.Signal support 1773 1774 static volatile jint sigint_count = 0; 1775 1776 static void UserHandler(int sig, void *siginfo, void *context) { 1777 // 4511530 - sem_post is serialized and handled by the manager thread. When 1778 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1779 // don't want to flood the manager thread with sem_post requests. 1780 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1781 return; 1782 } 1783 1784 // Ctrl-C is pressed during error reporting, likely because the error 1785 // handler fails to abort. Let VM die immediately. 1786 if (sig == SIGINT && VMError::is_error_reported()) { 1787 os::die(); 1788 } 1789 1790 os::signal_notify(sig); 1791 } 1792 1793 void* os::user_handler() { 1794 return CAST_FROM_FN_PTR(void*, UserHandler); 1795 } 1796 1797 extern "C" { 1798 typedef void (*sa_handler_t)(int); 1799 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1800 } 1801 1802 void* os::signal(int signal_number, void* handler) { 1803 struct sigaction sigAct, oldSigAct; 1804 1805 sigfillset(&(sigAct.sa_mask)); 1806 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1807 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1808 1809 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1810 // -1 means registration failed 1811 return (void *)-1; 1812 } 1813 1814 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1815 } 1816 1817 void os::signal_raise(int signal_number) { 1818 ::raise(signal_number); 1819 } 1820 1821 // The following code is moved from os.cpp for making this 1822 // code platform specific, which it is by its very nature. 1823 1824 // Will be modified when max signal is changed to be dynamic 1825 int os::sigexitnum_pd() { 1826 return NSIG; 1827 } 1828 1829 // a counter for each possible signal value 1830 static volatile jint pending_signals[NSIG+1] = { 0 }; 1831 static Semaphore* sig_sem = NULL; 1832 1833 static void jdk_misc_signal_init() { 1834 // Initialize signal structures 1835 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 1836 1837 // Initialize signal semaphore 1838 sig_sem = new Semaphore(); 1839 } 1840 1841 void os::signal_notify(int sig) { 1842 if (sig_sem != NULL) { 1843 Atomic::inc(&pending_signals[sig]); 1844 sig_sem->signal(); 1845 } else { 1846 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init 1847 // initialization isn't called. 1848 assert(ReduceSignalUsage, "signal semaphore should be created"); 1849 } 1850 } 1851 1852 static int check_pending_signals() { 1853 Atomic::store(0, &sigint_count); 1854 for (;;) { 1855 for (int i = 0; i < NSIG + 1; i++) { 1856 jint n = pending_signals[i]; 1857 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 1858 return i; 1859 } 1860 } 1861 JavaThread *thread = JavaThread::current(); 1862 ThreadBlockInVM tbivm(thread); 1863 1864 bool threadIsSuspended; 1865 do { 1866 thread->set_suspend_equivalent(); 1867 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 1868 sig_sem->wait(); 1869 1870 // were we externally suspended while we were waiting? 1871 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 1872 if (threadIsSuspended) { 1873 // The semaphore has been incremented, but while we were waiting 1874 // another thread suspended us. We don't want to continue running 1875 // while suspended because that would surprise the thread that 1876 // suspended us. 1877 sig_sem->signal(); 1878 1879 thread->java_suspend_self(); 1880 } 1881 } while (threadIsSuspended); 1882 } 1883 } 1884 1885 int os::signal_wait() { 1886 return check_pending_signals(); 1887 } 1888 1889 //////////////////////////////////////////////////////////////////////////////// 1890 // Virtual Memory 1891 1892 int os::vm_page_size() { 1893 // Seems redundant as all get out 1894 assert(os::Bsd::page_size() != -1, "must call os::init"); 1895 return os::Bsd::page_size(); 1896 } 1897 1898 // Solaris allocates memory by pages. 1899 int os::vm_allocation_granularity() { 1900 assert(os::Bsd::page_size() != -1, "must call os::init"); 1901 return os::Bsd::page_size(); 1902 } 1903 1904 // Rationale behind this function: 1905 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 1906 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 1907 // samples for JITted code. Here we create private executable mapping over the code cache 1908 // and then we can use standard (well, almost, as mapping can change) way to provide 1909 // info for the reporting script by storing timestamp and location of symbol 1910 void bsd_wrap_code(char* base, size_t size) { 1911 static volatile jint cnt = 0; 1912 1913 if (!UseOprofile) { 1914 return; 1915 } 1916 1917 char buf[PATH_MAX + 1]; 1918 int num = Atomic::add(1, &cnt); 1919 1920 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 1921 os::get_temp_directory(), os::current_process_id(), num); 1922 unlink(buf); 1923 1924 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 1925 1926 if (fd != -1) { 1927 off_t rv = ::lseek(fd, size-2, SEEK_SET); 1928 if (rv != (off_t)-1) { 1929 if (::write(fd, "", 1) == 1) { 1930 mmap(base, size, 1931 PROT_READ|PROT_WRITE|PROT_EXEC, 1932 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 1933 } 1934 } 1935 ::close(fd); 1936 unlink(buf); 1937 } 1938 } 1939 1940 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 1941 int err) { 1942 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT 1943 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec, 1944 os::errno_name(err), err); 1945 } 1946 1947 // NOTE: Bsd kernel does not really reserve the pages for us. 1948 // All it does is to check if there are enough free pages 1949 // left at the time of mmap(). This could be a potential 1950 // problem. 1951 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 1952 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 1953 #ifdef __OpenBSD__ 1954 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 1955 if (::mprotect(addr, size, prot) == 0) { 1956 return true; 1957 } 1958 #else 1959 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 1960 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 1961 if (res != (uintptr_t) MAP_FAILED) { 1962 return true; 1963 } 1964 #endif 1965 1966 // Warn about any commit errors we see in non-product builds just 1967 // in case mmap() doesn't work as described on the man page. 1968 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 1969 1970 return false; 1971 } 1972 1973 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 1974 bool exec) { 1975 // alignment_hint is ignored on this OS 1976 return pd_commit_memory(addr, size, exec); 1977 } 1978 1979 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 1980 const char* mesg) { 1981 assert(mesg != NULL, "mesg must be specified"); 1982 if (!pd_commit_memory(addr, size, exec)) { 1983 // add extra info in product mode for vm_exit_out_of_memory(): 1984 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 1985 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg); 1986 } 1987 } 1988 1989 void os::pd_commit_memory_or_exit(char* addr, size_t size, 1990 size_t alignment_hint, bool exec, 1991 const char* mesg) { 1992 // alignment_hint is ignored on this OS 1993 pd_commit_memory_or_exit(addr, size, exec, mesg); 1994 } 1995 1996 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 1997 } 1998 1999 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2000 ::madvise(addr, bytes, MADV_DONTNEED); 2001 } 2002 2003 void os::numa_make_global(char *addr, size_t bytes) { 2004 } 2005 2006 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2007 } 2008 2009 bool os::numa_topology_changed() { return false; } 2010 2011 size_t os::numa_get_groups_num() { 2012 return 1; 2013 } 2014 2015 int os::numa_get_group_id() { 2016 return 0; 2017 } 2018 2019 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2020 if (size > 0) { 2021 ids[0] = 0; 2022 return 1; 2023 } 2024 return 0; 2025 } 2026 2027 bool os::get_page_info(char *start, page_info* info) { 2028 return false; 2029 } 2030 2031 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2032 return end; 2033 } 2034 2035 2036 bool os::pd_uncommit_memory(char* addr, size_t size) { 2037 #ifdef __OpenBSD__ 2038 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2039 return ::mprotect(addr, size, PROT_NONE) == 0; 2040 #else 2041 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2042 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2043 return res != (uintptr_t) MAP_FAILED; 2044 #endif 2045 } 2046 2047 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2048 return os::commit_memory(addr, size, !ExecMem); 2049 } 2050 2051 // If this is a growable mapping, remove the guard pages entirely by 2052 // munmap()ping them. If not, just call uncommit_memory(). 2053 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2054 return os::uncommit_memory(addr, size); 2055 } 2056 2057 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2058 // at 'requested_addr'. If there are existing memory mappings at the same 2059 // location, however, they will be overwritten. If 'fixed' is false, 2060 // 'requested_addr' is only treated as a hint, the return value may or 2061 // may not start from the requested address. Unlike Bsd mmap(), this 2062 // function returns NULL to indicate failure. 2063 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2064 char * addr; 2065 int flags; 2066 2067 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2068 if (fixed) { 2069 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2070 flags |= MAP_FIXED; 2071 } 2072 2073 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2074 // touch an uncommitted page. Otherwise, the read/write might 2075 // succeed if we have enough swap space to back the physical page. 2076 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2077 flags, -1, 0); 2078 2079 return addr == MAP_FAILED ? NULL : addr; 2080 } 2081 2082 static int anon_munmap(char * addr, size_t size) { 2083 return ::munmap(addr, size) == 0; 2084 } 2085 2086 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2087 size_t alignment_hint) { 2088 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2089 } 2090 2091 bool os::pd_release_memory(char* addr, size_t size) { 2092 return anon_munmap(addr, size); 2093 } 2094 2095 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2096 // Bsd wants the mprotect address argument to be page aligned. 2097 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size()); 2098 2099 // According to SUSv3, mprotect() should only be used with mappings 2100 // established by mmap(), and mmap() always maps whole pages. Unaligned 2101 // 'addr' likely indicates problem in the VM (e.g. trying to change 2102 // protection of malloc'ed or statically allocated memory). Check the 2103 // caller if you hit this assert. 2104 assert(addr == bottom, "sanity check"); 2105 2106 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2107 return ::mprotect(bottom, size, prot) == 0; 2108 } 2109 2110 // Set protections specified 2111 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2112 bool is_committed) { 2113 unsigned int p = 0; 2114 switch (prot) { 2115 case MEM_PROT_NONE: p = PROT_NONE; break; 2116 case MEM_PROT_READ: p = PROT_READ; break; 2117 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2118 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2119 default: 2120 ShouldNotReachHere(); 2121 } 2122 // is_committed is unused. 2123 return bsd_mprotect(addr, bytes, p); 2124 } 2125 2126 bool os::guard_memory(char* addr, size_t size) { 2127 return bsd_mprotect(addr, size, PROT_NONE); 2128 } 2129 2130 bool os::unguard_memory(char* addr, size_t size) { 2131 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2132 } 2133 2134 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2135 return false; 2136 } 2137 2138 // Large page support 2139 2140 static size_t _large_page_size = 0; 2141 2142 void os::large_page_init() { 2143 } 2144 2145 2146 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2147 fatal("This code is not used or maintained."); 2148 2149 // "exec" is passed in but not used. Creating the shared image for 2150 // the code cache doesn't have an SHM_X executable permission to check. 2151 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2152 2153 key_t key = IPC_PRIVATE; 2154 char *addr; 2155 2156 bool warn_on_failure = UseLargePages && 2157 (!FLAG_IS_DEFAULT(UseLargePages) || 2158 !FLAG_IS_DEFAULT(LargePageSizeInBytes)); 2159 2160 // Create a large shared memory region to attach to based on size. 2161 // Currently, size is the total size of the heap 2162 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2163 if (shmid == -1) { 2164 // Possible reasons for shmget failure: 2165 // 1. shmmax is too small for Java heap. 2166 // > check shmmax value: cat /proc/sys/kernel/shmmax 2167 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2168 // 2. not enough large page memory. 2169 // > check available large pages: cat /proc/meminfo 2170 // > increase amount of large pages: 2171 // echo new_value > /proc/sys/vm/nr_hugepages 2172 // Note 1: different Bsd may use different name for this property, 2173 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2174 // Note 2: it's possible there's enough physical memory available but 2175 // they are so fragmented after a long run that they can't 2176 // coalesce into large pages. Try to reserve large pages when 2177 // the system is still "fresh". 2178 if (warn_on_failure) { 2179 warning("Failed to reserve shared memory (errno = %d).", errno); 2180 } 2181 return NULL; 2182 } 2183 2184 // attach to the region 2185 addr = (char*)shmat(shmid, req_addr, 0); 2186 int err = errno; 2187 2188 // Remove shmid. If shmat() is successful, the actual shared memory segment 2189 // will be deleted when it's detached by shmdt() or when the process 2190 // terminates. If shmat() is not successful this will remove the shared 2191 // segment immediately. 2192 shmctl(shmid, IPC_RMID, NULL); 2193 2194 if ((intptr_t)addr == -1) { 2195 if (warn_on_failure) { 2196 warning("Failed to attach shared memory (errno = %d).", err); 2197 } 2198 return NULL; 2199 } 2200 2201 // The memory is committed 2202 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2203 2204 return addr; 2205 } 2206 2207 bool os::release_memory_special(char* base, size_t bytes) { 2208 if (MemTracker::tracking_level() > NMT_minimal) { 2209 Tracker tkr(Tracker::release); 2210 // detaching the SHM segment will also delete it, see reserve_memory_special() 2211 int rslt = shmdt(base); 2212 if (rslt == 0) { 2213 tkr.record((address)base, bytes); 2214 return true; 2215 } else { 2216 return false; 2217 } 2218 } else { 2219 return shmdt(base) == 0; 2220 } 2221 } 2222 2223 size_t os::large_page_size() { 2224 return _large_page_size; 2225 } 2226 2227 // HugeTLBFS allows application to commit large page memory on demand; 2228 // with SysV SHM the entire memory region must be allocated as shared 2229 // memory. 2230 bool os::can_commit_large_page_memory() { 2231 return UseHugeTLBFS; 2232 } 2233 2234 bool os::can_execute_large_page_memory() { 2235 return UseHugeTLBFS; 2236 } 2237 2238 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) { 2239 assert(file_desc >= 0, "file_desc is not valid"); 2240 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr); 2241 if (result != NULL) { 2242 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) { 2243 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory")); 2244 } 2245 } 2246 return result; 2247 } 2248 2249 // Reserve memory at an arbitrary address, only if that area is 2250 // available (and not reserved for something else). 2251 2252 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2253 const int max_tries = 10; 2254 char* base[max_tries]; 2255 size_t size[max_tries]; 2256 const size_t gap = 0x000000; 2257 2258 // Assert only that the size is a multiple of the page size, since 2259 // that's all that mmap requires, and since that's all we really know 2260 // about at this low abstraction level. If we need higher alignment, 2261 // we can either pass an alignment to this method or verify alignment 2262 // in one of the methods further up the call chain. See bug 5044738. 2263 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2264 2265 // Repeatedly allocate blocks until the block is allocated at the 2266 // right spot. 2267 2268 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2269 // if kernel honors the hint then we can return immediately. 2270 char * addr = anon_mmap(requested_addr, bytes, false); 2271 if (addr == requested_addr) { 2272 return requested_addr; 2273 } 2274 2275 if (addr != NULL) { 2276 // mmap() is successful but it fails to reserve at the requested address 2277 anon_munmap(addr, bytes); 2278 } 2279 2280 int i; 2281 for (i = 0; i < max_tries; ++i) { 2282 base[i] = reserve_memory(bytes); 2283 2284 if (base[i] != NULL) { 2285 // Is this the block we wanted? 2286 if (base[i] == requested_addr) { 2287 size[i] = bytes; 2288 break; 2289 } 2290 2291 // Does this overlap the block we wanted? Give back the overlapped 2292 // parts and try again. 2293 2294 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2295 if (top_overlap >= 0 && top_overlap < bytes) { 2296 unmap_memory(base[i], top_overlap); 2297 base[i] += top_overlap; 2298 size[i] = bytes - top_overlap; 2299 } else { 2300 size_t bottom_overlap = base[i] + bytes - requested_addr; 2301 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2302 unmap_memory(requested_addr, bottom_overlap); 2303 size[i] = bytes - bottom_overlap; 2304 } else { 2305 size[i] = bytes; 2306 } 2307 } 2308 } 2309 } 2310 2311 // Give back the unused reserved pieces. 2312 2313 for (int j = 0; j < i; ++j) { 2314 if (base[j] != NULL) { 2315 unmap_memory(base[j], size[j]); 2316 } 2317 } 2318 2319 if (i < max_tries) { 2320 return requested_addr; 2321 } else { 2322 return NULL; 2323 } 2324 } 2325 2326 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2327 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2328 } 2329 2330 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2331 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2332 } 2333 2334 void os::naked_short_sleep(jlong ms) { 2335 struct timespec req; 2336 2337 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2338 req.tv_sec = 0; 2339 if (ms > 0) { 2340 req.tv_nsec = (ms % 1000) * 1000000; 2341 } else { 2342 req.tv_nsec = 1; 2343 } 2344 2345 nanosleep(&req, NULL); 2346 2347 return; 2348 } 2349 2350 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2351 void os::infinite_sleep() { 2352 while (true) { // sleep forever ... 2353 ::sleep(100); // ... 100 seconds at a time 2354 } 2355 } 2356 2357 // Used to convert frequent JVM_Yield() to nops 2358 bool os::dont_yield() { 2359 return DontYieldALot; 2360 } 2361 2362 void os::naked_yield() { 2363 sched_yield(); 2364 } 2365 2366 //////////////////////////////////////////////////////////////////////////////// 2367 // thread priority support 2368 2369 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2370 // only supports dynamic priority, static priority must be zero. For real-time 2371 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2372 // However, for large multi-threaded applications, SCHED_RR is not only slower 2373 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2374 // of 5 runs - Sep 2005). 2375 // 2376 // The following code actually changes the niceness of kernel-thread/LWP. It 2377 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2378 // not the entire user process, and user level threads are 1:1 mapped to kernel 2379 // threads. It has always been the case, but could change in the future. For 2380 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2381 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2382 2383 #if !defined(__APPLE__) 2384 int os::java_to_os_priority[CriticalPriority + 1] = { 2385 19, // 0 Entry should never be used 2386 2387 0, // 1 MinPriority 2388 3, // 2 2389 6, // 3 2390 2391 10, // 4 2392 15, // 5 NormPriority 2393 18, // 6 2394 2395 21, // 7 2396 25, // 8 2397 28, // 9 NearMaxPriority 2398 2399 31, // 10 MaxPriority 2400 2401 31 // 11 CriticalPriority 2402 }; 2403 #else 2404 // Using Mach high-level priority assignments 2405 int os::java_to_os_priority[CriticalPriority + 1] = { 2406 0, // 0 Entry should never be used (MINPRI_USER) 2407 2408 27, // 1 MinPriority 2409 28, // 2 2410 29, // 3 2411 2412 30, // 4 2413 31, // 5 NormPriority (BASEPRI_DEFAULT) 2414 32, // 6 2415 2416 33, // 7 2417 34, // 8 2418 35, // 9 NearMaxPriority 2419 2420 36, // 10 MaxPriority 2421 2422 36 // 11 CriticalPriority 2423 }; 2424 #endif 2425 2426 static int prio_init() { 2427 if (ThreadPriorityPolicy == 1) { 2428 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2429 // if effective uid is not root. Perhaps, a more elegant way of doing 2430 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2431 if (geteuid() != 0) { 2432 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2433 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2434 } 2435 ThreadPriorityPolicy = 0; 2436 } 2437 } 2438 if (UseCriticalJavaThreadPriority) { 2439 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2440 } 2441 return 0; 2442 } 2443 2444 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2445 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2446 2447 #ifdef __OpenBSD__ 2448 // OpenBSD pthread_setprio starves low priority threads 2449 return OS_OK; 2450 #elif defined(__FreeBSD__) 2451 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2452 #elif defined(__APPLE__) || defined(__NetBSD__) 2453 struct sched_param sp; 2454 int policy; 2455 pthread_t self = pthread_self(); 2456 2457 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2458 return OS_ERR; 2459 } 2460 2461 sp.sched_priority = newpri; 2462 if (pthread_setschedparam(self, policy, &sp) != 0) { 2463 return OS_ERR; 2464 } 2465 2466 return OS_OK; 2467 #else 2468 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2469 return (ret == 0) ? OS_OK : OS_ERR; 2470 #endif 2471 } 2472 2473 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2474 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2475 *priority_ptr = java_to_os_priority[NormPriority]; 2476 return OS_OK; 2477 } 2478 2479 errno = 0; 2480 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2481 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2482 #elif defined(__APPLE__) || defined(__NetBSD__) 2483 int policy; 2484 struct sched_param sp; 2485 2486 pthread_getschedparam(pthread_self(), &policy, &sp); 2487 *priority_ptr = sp.sched_priority; 2488 #else 2489 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2490 #endif 2491 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2492 } 2493 2494 // Hint to the underlying OS that a task switch would not be good. 2495 // Void return because it's a hint and can fail. 2496 void os::hint_no_preempt() {} 2497 2498 //////////////////////////////////////////////////////////////////////////////// 2499 // suspend/resume support 2500 2501 // The low-level signal-based suspend/resume support is a remnant from the 2502 // old VM-suspension that used to be for java-suspension, safepoints etc, 2503 // within hotspot. Currently used by JFR's OSThreadSampler 2504 // 2505 // The remaining code is greatly simplified from the more general suspension 2506 // code that used to be used. 2507 // 2508 // The protocol is quite simple: 2509 // - suspend: 2510 // - sends a signal to the target thread 2511 // - polls the suspend state of the osthread using a yield loop 2512 // - target thread signal handler (SR_handler) sets suspend state 2513 // and blocks in sigsuspend until continued 2514 // - resume: 2515 // - sets target osthread state to continue 2516 // - sends signal to end the sigsuspend loop in the SR_handler 2517 // 2518 // Note that the SR_lock plays no role in this suspend/resume protocol, 2519 // but is checked for NULL in SR_handler as a thread termination indicator. 2520 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs. 2521 // 2522 // Note that resume_clear_context() and suspend_save_context() are needed 2523 // by SR_handler(), so that fetch_frame_from_ucontext() works, 2524 // which in part is used by: 2525 // - Forte Analyzer: AsyncGetCallTrace() 2526 // - StackBanging: get_frame_at_stack_banging_point() 2527 2528 static void resume_clear_context(OSThread *osthread) { 2529 osthread->set_ucontext(NULL); 2530 osthread->set_siginfo(NULL); 2531 } 2532 2533 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2534 osthread->set_ucontext(context); 2535 osthread->set_siginfo(siginfo); 2536 } 2537 2538 // Handler function invoked when a thread's execution is suspended or 2539 // resumed. We have to be careful that only async-safe functions are 2540 // called here (Note: most pthread functions are not async safe and 2541 // should be avoided.) 2542 // 2543 // Note: sigwait() is a more natural fit than sigsuspend() from an 2544 // interface point of view, but sigwait() prevents the signal hander 2545 // from being run. libpthread would get very confused by not having 2546 // its signal handlers run and prevents sigwait()'s use with the 2547 // mutex granting granting signal. 2548 // 2549 // Currently only ever called on the VMThread or JavaThread 2550 // 2551 #ifdef __APPLE__ 2552 static OSXSemaphore sr_semaphore; 2553 #else 2554 static PosixSemaphore sr_semaphore; 2555 #endif 2556 2557 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2558 // Save and restore errno to avoid confusing native code with EINTR 2559 // after sigsuspend. 2560 int old_errno = errno; 2561 2562 Thread* thread = Thread::current_or_null_safe(); 2563 assert(thread != NULL, "Missing current thread in SR_handler"); 2564 2565 // On some systems we have seen signal delivery get "stuck" until the signal 2566 // mask is changed as part of thread termination. Check that the current thread 2567 // has not already terminated (via SR_lock()) - else the following assertion 2568 // will fail because the thread is no longer a JavaThread as the ~JavaThread 2569 // destructor has completed. 2570 2571 if (thread->SR_lock() == NULL) { 2572 return; 2573 } 2574 2575 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2576 2577 OSThread* osthread = thread->osthread(); 2578 2579 os::SuspendResume::State current = osthread->sr.state(); 2580 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2581 suspend_save_context(osthread, siginfo, context); 2582 2583 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2584 os::SuspendResume::State state = osthread->sr.suspended(); 2585 if (state == os::SuspendResume::SR_SUSPENDED) { 2586 sigset_t suspend_set; // signals for sigsuspend() 2587 2588 // get current set of blocked signals and unblock resume signal 2589 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2590 sigdelset(&suspend_set, SR_signum); 2591 2592 sr_semaphore.signal(); 2593 // wait here until we are resumed 2594 while (1) { 2595 sigsuspend(&suspend_set); 2596 2597 os::SuspendResume::State result = osthread->sr.running(); 2598 if (result == os::SuspendResume::SR_RUNNING) { 2599 sr_semaphore.signal(); 2600 break; 2601 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2602 ShouldNotReachHere(); 2603 } 2604 } 2605 2606 } else if (state == os::SuspendResume::SR_RUNNING) { 2607 // request was cancelled, continue 2608 } else { 2609 ShouldNotReachHere(); 2610 } 2611 2612 resume_clear_context(osthread); 2613 } else if (current == os::SuspendResume::SR_RUNNING) { 2614 // request was cancelled, continue 2615 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2616 // ignore 2617 } else { 2618 // ignore 2619 } 2620 2621 errno = old_errno; 2622 } 2623 2624 2625 static int SR_initialize() { 2626 struct sigaction act; 2627 char *s; 2628 // Get signal number to use for suspend/resume 2629 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2630 int sig = ::strtol(s, 0, 10); 2631 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769. 2632 sig < NSIG) { // Must be legal signal and fit into sigflags[]. 2633 SR_signum = sig; 2634 } else { 2635 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.", 2636 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum); 2637 } 2638 } 2639 2640 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2641 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2642 2643 sigemptyset(&SR_sigset); 2644 sigaddset(&SR_sigset, SR_signum); 2645 2646 // Set up signal handler for suspend/resume 2647 act.sa_flags = SA_RESTART|SA_SIGINFO; 2648 act.sa_handler = (void (*)(int)) SR_handler; 2649 2650 // SR_signum is blocked by default. 2651 // 4528190 - We also need to block pthread restart signal (32 on all 2652 // supported Bsd platforms). Note that BsdThreads need to block 2653 // this signal for all threads to work properly. So we don't have 2654 // to use hard-coded signal number when setting up the mask. 2655 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2656 2657 if (sigaction(SR_signum, &act, 0) == -1) { 2658 return -1; 2659 } 2660 2661 // Save signal flag 2662 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2663 return 0; 2664 } 2665 2666 static int sr_notify(OSThread* osthread) { 2667 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2668 assert_status(status == 0, status, "pthread_kill"); 2669 return status; 2670 } 2671 2672 // "Randomly" selected value for how long we want to spin 2673 // before bailing out on suspending a thread, also how often 2674 // we send a signal to a thread we want to resume 2675 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2676 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2677 2678 // returns true on success and false on error - really an error is fatal 2679 // but this seems the normal response to library errors 2680 static bool do_suspend(OSThread* osthread) { 2681 assert(osthread->sr.is_running(), "thread should be running"); 2682 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2683 2684 // mark as suspended and send signal 2685 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2686 // failed to switch, state wasn't running? 2687 ShouldNotReachHere(); 2688 return false; 2689 } 2690 2691 if (sr_notify(osthread) != 0) { 2692 ShouldNotReachHere(); 2693 } 2694 2695 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2696 while (true) { 2697 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2698 break; 2699 } else { 2700 // timeout 2701 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2702 if (cancelled == os::SuspendResume::SR_RUNNING) { 2703 return false; 2704 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2705 // make sure that we consume the signal on the semaphore as well 2706 sr_semaphore.wait(); 2707 break; 2708 } else { 2709 ShouldNotReachHere(); 2710 return false; 2711 } 2712 } 2713 } 2714 2715 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2716 return true; 2717 } 2718 2719 static void do_resume(OSThread* osthread) { 2720 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2721 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2722 2723 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2724 // failed to switch to WAKEUP_REQUEST 2725 ShouldNotReachHere(); 2726 return; 2727 } 2728 2729 while (true) { 2730 if (sr_notify(osthread) == 0) { 2731 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2732 if (osthread->sr.is_running()) { 2733 return; 2734 } 2735 } 2736 } else { 2737 ShouldNotReachHere(); 2738 } 2739 } 2740 2741 guarantee(osthread->sr.is_running(), "Must be running!"); 2742 } 2743 2744 /////////////////////////////////////////////////////////////////////////////////// 2745 // signal handling (except suspend/resume) 2746 2747 // This routine may be used by user applications as a "hook" to catch signals. 2748 // The user-defined signal handler must pass unrecognized signals to this 2749 // routine, and if it returns true (non-zero), then the signal handler must 2750 // return immediately. If the flag "abort_if_unrecognized" is true, then this 2751 // routine will never retun false (zero), but instead will execute a VM panic 2752 // routine kill the process. 2753 // 2754 // If this routine returns false, it is OK to call it again. This allows 2755 // the user-defined signal handler to perform checks either before or after 2756 // the VM performs its own checks. Naturally, the user code would be making 2757 // a serious error if it tried to handle an exception (such as a null check 2758 // or breakpoint) that the VM was generating for its own correct operation. 2759 // 2760 // This routine may recognize any of the following kinds of signals: 2761 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2762 // It should be consulted by handlers for any of those signals. 2763 // 2764 // The caller of this routine must pass in the three arguments supplied 2765 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 2766 // field of the structure passed to sigaction(). This routine assumes that 2767 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2768 // 2769 // Note that the VM will print warnings if it detects conflicting signal 2770 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2771 // 2772 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2773 void* ucontext, 2774 int abort_if_unrecognized); 2775 2776 static void signalHandler(int sig, siginfo_t* info, void* uc) { 2777 assert(info != NULL && uc != NULL, "it must be old kernel"); 2778 int orig_errno = errno; // Preserve errno value over signal handler. 2779 JVM_handle_bsd_signal(sig, info, uc, true); 2780 errno = orig_errno; 2781 } 2782 2783 2784 // This boolean allows users to forward their own non-matching signals 2785 // to JVM_handle_bsd_signal, harmlessly. 2786 bool os::Bsd::signal_handlers_are_installed = false; 2787 2788 // For signal-chaining 2789 struct sigaction sigact[NSIG]; 2790 uint32_t sigs = 0; 2791 #if (32 < NSIG-1) 2792 #error "Not all signals can be encoded in sigs. Adapt its type!" 2793 #endif 2794 bool os::Bsd::libjsig_is_loaded = false; 2795 typedef struct sigaction *(*get_signal_t)(int); 2796 get_signal_t os::Bsd::get_signal_action = NULL; 2797 2798 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2799 struct sigaction *actp = NULL; 2800 2801 if (libjsig_is_loaded) { 2802 // Retrieve the old signal handler from libjsig 2803 actp = (*get_signal_action)(sig); 2804 } 2805 if (actp == NULL) { 2806 // Retrieve the preinstalled signal handler from jvm 2807 actp = get_preinstalled_handler(sig); 2808 } 2809 2810 return actp; 2811 } 2812 2813 static bool call_chained_handler(struct sigaction *actp, int sig, 2814 siginfo_t *siginfo, void *context) { 2815 // Call the old signal handler 2816 if (actp->sa_handler == SIG_DFL) { 2817 // It's more reasonable to let jvm treat it as an unexpected exception 2818 // instead of taking the default action. 2819 return false; 2820 } else if (actp->sa_handler != SIG_IGN) { 2821 if ((actp->sa_flags & SA_NODEFER) == 0) { 2822 // automaticlly block the signal 2823 sigaddset(&(actp->sa_mask), sig); 2824 } 2825 2826 sa_handler_t hand; 2827 sa_sigaction_t sa; 2828 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 2829 // retrieve the chained handler 2830 if (siginfo_flag_set) { 2831 sa = actp->sa_sigaction; 2832 } else { 2833 hand = actp->sa_handler; 2834 } 2835 2836 if ((actp->sa_flags & SA_RESETHAND) != 0) { 2837 actp->sa_handler = SIG_DFL; 2838 } 2839 2840 // try to honor the signal mask 2841 sigset_t oset; 2842 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 2843 2844 // call into the chained handler 2845 if (siginfo_flag_set) { 2846 (*sa)(sig, siginfo, context); 2847 } else { 2848 (*hand)(sig); 2849 } 2850 2851 // restore the signal mask 2852 pthread_sigmask(SIG_SETMASK, &oset, 0); 2853 } 2854 // Tell jvm's signal handler the signal is taken care of. 2855 return true; 2856 } 2857 2858 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 2859 bool chained = false; 2860 // signal-chaining 2861 if (UseSignalChaining) { 2862 struct sigaction *actp = get_chained_signal_action(sig); 2863 if (actp != NULL) { 2864 chained = call_chained_handler(actp, sig, siginfo, context); 2865 } 2866 } 2867 return chained; 2868 } 2869 2870 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 2871 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) { 2872 return &sigact[sig]; 2873 } 2874 return NULL; 2875 } 2876 2877 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 2878 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2879 sigact[sig] = oldAct; 2880 sigs |= (uint32_t)1 << (sig-1); 2881 } 2882 2883 // for diagnostic 2884 int sigflags[NSIG]; 2885 2886 int os::Bsd::get_our_sigflags(int sig) { 2887 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2888 return sigflags[sig]; 2889 } 2890 2891 void os::Bsd::set_our_sigflags(int sig, int flags) { 2892 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2893 if (sig > 0 && sig < NSIG) { 2894 sigflags[sig] = flags; 2895 } 2896 } 2897 2898 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 2899 // Check for overwrite. 2900 struct sigaction oldAct; 2901 sigaction(sig, (struct sigaction*)NULL, &oldAct); 2902 2903 void* oldhand = oldAct.sa_sigaction 2904 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 2905 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 2906 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 2907 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 2908 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 2909 if (AllowUserSignalHandlers || !set_installed) { 2910 // Do not overwrite; user takes responsibility to forward to us. 2911 return; 2912 } else if (UseSignalChaining) { 2913 // save the old handler in jvm 2914 save_preinstalled_handler(sig, oldAct); 2915 // libjsig also interposes the sigaction() call below and saves the 2916 // old sigaction on it own. 2917 } else { 2918 fatal("Encountered unexpected pre-existing sigaction handler " 2919 "%#lx for signal %d.", (long)oldhand, sig); 2920 } 2921 } 2922 2923 struct sigaction sigAct; 2924 sigfillset(&(sigAct.sa_mask)); 2925 sigAct.sa_handler = SIG_DFL; 2926 if (!set_installed) { 2927 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 2928 } else { 2929 sigAct.sa_sigaction = signalHandler; 2930 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 2931 } 2932 #ifdef __APPLE__ 2933 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 2934 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 2935 // if the signal handler declares it will handle it on alternate stack. 2936 // Notice we only declare we will handle it on alt stack, but we are not 2937 // actually going to use real alt stack - this is just a workaround. 2938 // Please see ux_exception.c, method catch_mach_exception_raise for details 2939 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 2940 if (sig == SIGSEGV) { 2941 sigAct.sa_flags |= SA_ONSTACK; 2942 } 2943 #endif 2944 2945 // Save flags, which are set by ours 2946 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 2947 sigflags[sig] = sigAct.sa_flags; 2948 2949 int ret = sigaction(sig, &sigAct, &oldAct); 2950 assert(ret == 0, "check"); 2951 2952 void* oldhand2 = oldAct.sa_sigaction 2953 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 2954 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 2955 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 2956 } 2957 2958 // install signal handlers for signals that HotSpot needs to 2959 // handle in order to support Java-level exception handling. 2960 2961 void os::Bsd::install_signal_handlers() { 2962 if (!signal_handlers_are_installed) { 2963 signal_handlers_are_installed = true; 2964 2965 // signal-chaining 2966 typedef void (*signal_setting_t)(); 2967 signal_setting_t begin_signal_setting = NULL; 2968 signal_setting_t end_signal_setting = NULL; 2969 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 2970 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 2971 if (begin_signal_setting != NULL) { 2972 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 2973 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 2974 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 2975 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 2976 libjsig_is_loaded = true; 2977 assert(UseSignalChaining, "should enable signal-chaining"); 2978 } 2979 if (libjsig_is_loaded) { 2980 // Tell libjsig jvm is setting signal handlers 2981 (*begin_signal_setting)(); 2982 } 2983 2984 set_signal_handler(SIGSEGV, true); 2985 set_signal_handler(SIGPIPE, true); 2986 set_signal_handler(SIGBUS, true); 2987 set_signal_handler(SIGILL, true); 2988 set_signal_handler(SIGFPE, true); 2989 set_signal_handler(SIGXFSZ, true); 2990 2991 #if defined(__APPLE__) 2992 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 2993 // signals caught and handled by the JVM. To work around this, we reset the mach task 2994 // signal handler that's placed on our process by CrashReporter. This disables 2995 // CrashReporter-based reporting. 2996 // 2997 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 2998 // on caught fatal signals. 2999 // 3000 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3001 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3002 // exception handling, while leaving the standard BSD signal handlers functional. 3003 kern_return_t kr; 3004 kr = task_set_exception_ports(mach_task_self(), 3005 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3006 MACH_PORT_NULL, 3007 EXCEPTION_STATE_IDENTITY, 3008 MACHINE_THREAD_STATE); 3009 3010 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3011 #endif 3012 3013 if (libjsig_is_loaded) { 3014 // Tell libjsig jvm finishes setting signal handlers 3015 (*end_signal_setting)(); 3016 } 3017 3018 // We don't activate signal checker if libjsig is in place, we trust ourselves 3019 // and if UserSignalHandler is installed all bets are off 3020 if (CheckJNICalls) { 3021 if (libjsig_is_loaded) { 3022 if (PrintJNIResolving) { 3023 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3024 } 3025 check_signals = false; 3026 } 3027 if (AllowUserSignalHandlers) { 3028 if (PrintJNIResolving) { 3029 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3030 } 3031 check_signals = false; 3032 } 3033 } 3034 } 3035 } 3036 3037 3038 ///// 3039 // glibc on Bsd platform uses non-documented flag 3040 // to indicate, that some special sort of signal 3041 // trampoline is used. 3042 // We will never set this flag, and we should 3043 // ignore this flag in our diagnostic 3044 #ifdef SIGNIFICANT_SIGNAL_MASK 3045 #undef SIGNIFICANT_SIGNAL_MASK 3046 #endif 3047 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3048 3049 static const char* get_signal_handler_name(address handler, 3050 char* buf, int buflen) { 3051 int offset; 3052 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3053 if (found) { 3054 // skip directory names 3055 const char *p1, *p2; 3056 p1 = buf; 3057 size_t len = strlen(os::file_separator()); 3058 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3059 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3060 } else { 3061 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3062 } 3063 return buf; 3064 } 3065 3066 static void print_signal_handler(outputStream* st, int sig, 3067 char* buf, size_t buflen) { 3068 struct sigaction sa; 3069 3070 sigaction(sig, NULL, &sa); 3071 3072 // See comment for SIGNIFICANT_SIGNAL_MASK define 3073 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3074 3075 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3076 3077 address handler = (sa.sa_flags & SA_SIGINFO) 3078 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3079 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3080 3081 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3082 st->print("SIG_DFL"); 3083 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3084 st->print("SIG_IGN"); 3085 } else { 3086 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3087 } 3088 3089 st->print(", sa_mask[0]="); 3090 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3091 3092 address rh = VMError::get_resetted_sighandler(sig); 3093 // May be, handler was resetted by VMError? 3094 if (rh != NULL) { 3095 handler = rh; 3096 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3097 } 3098 3099 st->print(", sa_flags="); 3100 os::Posix::print_sa_flags(st, sa.sa_flags); 3101 3102 // Check: is it our handler? 3103 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3104 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3105 // It is our signal handler 3106 // check for flags, reset system-used one! 3107 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3108 st->print( 3109 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3110 os::Bsd::get_our_sigflags(sig)); 3111 } 3112 } 3113 st->cr(); 3114 } 3115 3116 3117 #define DO_SIGNAL_CHECK(sig) \ 3118 do { \ 3119 if (!sigismember(&check_signal_done, sig)) { \ 3120 os::Bsd::check_signal_handler(sig); \ 3121 } \ 3122 } while (0) 3123 3124 // This method is a periodic task to check for misbehaving JNI applications 3125 // under CheckJNI, we can add any periodic checks here 3126 3127 void os::run_periodic_checks() { 3128 3129 if (check_signals == false) return; 3130 3131 // SEGV and BUS if overridden could potentially prevent 3132 // generation of hs*.log in the event of a crash, debugging 3133 // such a case can be very challenging, so we absolutely 3134 // check the following for a good measure: 3135 DO_SIGNAL_CHECK(SIGSEGV); 3136 DO_SIGNAL_CHECK(SIGILL); 3137 DO_SIGNAL_CHECK(SIGFPE); 3138 DO_SIGNAL_CHECK(SIGBUS); 3139 DO_SIGNAL_CHECK(SIGPIPE); 3140 DO_SIGNAL_CHECK(SIGXFSZ); 3141 3142 3143 // ReduceSignalUsage allows the user to override these handlers 3144 // see comments at the very top and jvm_md.h 3145 if (!ReduceSignalUsage) { 3146 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3147 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3148 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3149 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3150 } 3151 3152 DO_SIGNAL_CHECK(SR_signum); 3153 } 3154 3155 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3156 3157 static os_sigaction_t os_sigaction = NULL; 3158 3159 void os::Bsd::check_signal_handler(int sig) { 3160 char buf[O_BUFLEN]; 3161 address jvmHandler = NULL; 3162 3163 3164 struct sigaction act; 3165 if (os_sigaction == NULL) { 3166 // only trust the default sigaction, in case it has been interposed 3167 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3168 if (os_sigaction == NULL) return; 3169 } 3170 3171 os_sigaction(sig, (struct sigaction*)NULL, &act); 3172 3173 3174 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3175 3176 address thisHandler = (act.sa_flags & SA_SIGINFO) 3177 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3178 : CAST_FROM_FN_PTR(address, act.sa_handler); 3179 3180 3181 switch (sig) { 3182 case SIGSEGV: 3183 case SIGBUS: 3184 case SIGFPE: 3185 case SIGPIPE: 3186 case SIGILL: 3187 case SIGXFSZ: 3188 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3189 break; 3190 3191 case SHUTDOWN1_SIGNAL: 3192 case SHUTDOWN2_SIGNAL: 3193 case SHUTDOWN3_SIGNAL: 3194 case BREAK_SIGNAL: 3195 jvmHandler = (address)user_handler(); 3196 break; 3197 3198 default: 3199 if (sig == SR_signum) { 3200 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3201 } else { 3202 return; 3203 } 3204 break; 3205 } 3206 3207 if (thisHandler != jvmHandler) { 3208 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3209 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3210 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3211 // No need to check this sig any longer 3212 sigaddset(&check_signal_done, sig); 3213 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3214 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3215 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3216 exception_name(sig, buf, O_BUFLEN)); 3217 } 3218 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3219 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3220 tty->print("expected:"); 3221 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig)); 3222 tty->cr(); 3223 tty->print(" found:"); 3224 os::Posix::print_sa_flags(tty, act.sa_flags); 3225 tty->cr(); 3226 // No need to check this sig any longer 3227 sigaddset(&check_signal_done, sig); 3228 } 3229 3230 // Dump all the signal 3231 if (sigismember(&check_signal_done, sig)) { 3232 print_signal_handlers(tty, buf, O_BUFLEN); 3233 } 3234 } 3235 3236 extern void report_error(char* file_name, int line_no, char* title, 3237 char* format, ...); 3238 3239 // this is called _before_ the most of global arguments have been parsed 3240 void os::init(void) { 3241 char dummy; // used to get a guess on initial stack address 3242 3243 // With BsdThreads the JavaMain thread pid (primordial thread) 3244 // is different than the pid of the java launcher thread. 3245 // So, on Bsd, the launcher thread pid is passed to the VM 3246 // via the sun.java.launcher.pid property. 3247 // Use this property instead of getpid() if it was correctly passed. 3248 // See bug 6351349. 3249 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3250 3251 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3252 3253 clock_tics_per_sec = CLK_TCK; 3254 3255 init_random(1234567); 3256 3257 Bsd::set_page_size(getpagesize()); 3258 if (Bsd::page_size() == -1) { 3259 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno)); 3260 } 3261 init_page_sizes((size_t) Bsd::page_size()); 3262 3263 Bsd::initialize_system_info(); 3264 3265 // _main_thread points to the thread that created/loaded the JVM. 3266 Bsd::_main_thread = pthread_self(); 3267 3268 Bsd::clock_init(); 3269 initial_time_count = javaTimeNanos(); 3270 3271 #ifdef __APPLE__ 3272 // XXXDARWIN 3273 // Work around the unaligned VM callbacks in hotspot's 3274 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3275 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3276 // alignment when doing symbol lookup. To work around this, we force early 3277 // binding of all symbols now, thus binding when alignment is known-good. 3278 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3279 #endif 3280 3281 os::Posix::init(); 3282 } 3283 3284 // To install functions for atexit system call 3285 extern "C" { 3286 static void perfMemory_exit_helper() { 3287 perfMemory_exit(); 3288 } 3289 } 3290 3291 // this is called _after_ the global arguments have been parsed 3292 jint os::init_2(void) { 3293 3294 os::Posix::init_2(); 3295 3296 // initialize suspend/resume support - must do this before signal_sets_init() 3297 if (SR_initialize() != 0) { 3298 perror("SR_initialize failed"); 3299 return JNI_ERR; 3300 } 3301 3302 Bsd::signal_sets_init(); 3303 Bsd::install_signal_handlers(); 3304 // Initialize data for jdk.internal.misc.Signal 3305 if (!ReduceSignalUsage) { 3306 jdk_misc_signal_init(); 3307 } 3308 3309 // Check and sets minimum stack sizes against command line options 3310 if (Posix::set_minimum_stack_sizes() == JNI_ERR) { 3311 return JNI_ERR; 3312 } 3313 3314 if (MaxFDLimit) { 3315 // set the number of file descriptors to max. print out error 3316 // if getrlimit/setrlimit fails but continue regardless. 3317 struct rlimit nbr_files; 3318 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3319 if (status != 0) { 3320 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno)); 3321 } else { 3322 nbr_files.rlim_cur = nbr_files.rlim_max; 3323 3324 #ifdef __APPLE__ 3325 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3326 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3327 // be used instead 3328 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3329 #endif 3330 3331 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3332 if (status != 0) { 3333 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno)); 3334 } 3335 } 3336 } 3337 3338 // at-exit methods are called in the reverse order of their registration. 3339 // atexit functions are called on return from main or as a result of a 3340 // call to exit(3C). There can be only 32 of these functions registered 3341 // and atexit() does not set errno. 3342 3343 if (PerfAllowAtExitRegistration) { 3344 // only register atexit functions if PerfAllowAtExitRegistration is set. 3345 // atexit functions can be delayed until process exit time, which 3346 // can be problematic for embedded VM situations. Embedded VMs should 3347 // call DestroyJavaVM() to assure that VM resources are released. 3348 3349 // note: perfMemory_exit_helper atexit function may be removed in 3350 // the future if the appropriate cleanup code can be added to the 3351 // VM_Exit VMOperation's doit method. 3352 if (atexit(perfMemory_exit_helper) != 0) { 3353 warning("os::init_2 atexit(perfMemory_exit_helper) failed"); 3354 } 3355 } 3356 3357 // initialize thread priority policy 3358 prio_init(); 3359 3360 #ifdef __APPLE__ 3361 // dynamically link to objective c gc registration 3362 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3363 if (handleLibObjc != NULL) { 3364 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3365 } 3366 #endif 3367 3368 return JNI_OK; 3369 } 3370 3371 // Mark the polling page as unreadable 3372 void os::make_polling_page_unreadable(void) { 3373 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3374 fatal("Could not disable polling page"); 3375 } 3376 } 3377 3378 // Mark the polling page as readable 3379 void os::make_polling_page_readable(void) { 3380 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3381 fatal("Could not enable polling page"); 3382 } 3383 } 3384 3385 int os::active_processor_count() { 3386 // User has overridden the number of active processors 3387 if (ActiveProcessorCount > 0) { 3388 log_trace(os)("active_processor_count: " 3389 "active processor count set by user : %d", 3390 ActiveProcessorCount); 3391 return ActiveProcessorCount; 3392 } 3393 3394 return _processor_count; 3395 } 3396 3397 void os::set_native_thread_name(const char *name) { 3398 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3399 // This is only supported in Snow Leopard and beyond 3400 if (name != NULL) { 3401 // Add a "Java: " prefix to the name 3402 char buf[MAXTHREADNAMESIZE]; 3403 snprintf(buf, sizeof(buf), "Java: %s", name); 3404 pthread_setname_np(buf); 3405 } 3406 #endif 3407 } 3408 3409 bool os::distribute_processes(uint length, uint* distribution) { 3410 // Not yet implemented. 3411 return false; 3412 } 3413 3414 bool os::bind_to_processor(uint processor_id) { 3415 // Not yet implemented. 3416 return false; 3417 } 3418 3419 void os::SuspendedThreadTask::internal_do_task() { 3420 if (do_suspend(_thread->osthread())) { 3421 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3422 do_task(context); 3423 do_resume(_thread->osthread()); 3424 } 3425 } 3426 3427 //////////////////////////////////////////////////////////////////////////////// 3428 // debug support 3429 3430 bool os::find(address addr, outputStream* st) { 3431 Dl_info dlinfo; 3432 memset(&dlinfo, 0, sizeof(dlinfo)); 3433 if (dladdr(addr, &dlinfo) != 0) { 3434 st->print(INTPTR_FORMAT ": ", (intptr_t)addr); 3435 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3436 st->print("%s+%#x", dlinfo.dli_sname, 3437 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr)); 3438 } else if (dlinfo.dli_fbase != NULL) { 3439 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase)); 3440 } else { 3441 st->print("<absolute address>"); 3442 } 3443 if (dlinfo.dli_fname != NULL) { 3444 st->print(" in %s", dlinfo.dli_fname); 3445 } 3446 if (dlinfo.dli_fbase != NULL) { 3447 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase); 3448 } 3449 st->cr(); 3450 3451 if (Verbose) { 3452 // decode some bytes around the PC 3453 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3454 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3455 address lowest = (address) dlinfo.dli_sname; 3456 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3457 if (begin < lowest) begin = lowest; 3458 Dl_info dlinfo2; 3459 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3460 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3461 end = (address) dlinfo2.dli_saddr; 3462 } 3463 Disassembler::decode(begin, end, st); 3464 } 3465 return true; 3466 } 3467 return false; 3468 } 3469 3470 //////////////////////////////////////////////////////////////////////////////// 3471 // misc 3472 3473 // This does not do anything on Bsd. This is basically a hook for being 3474 // able to use structured exception handling (thread-local exception filters) 3475 // on, e.g., Win32. 3476 void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3477 const methodHandle& method, JavaCallArguments* args, 3478 Thread* thread) { 3479 f(value, method, args, thread); 3480 } 3481 3482 void os::print_statistics() { 3483 } 3484 3485 bool os::message_box(const char* title, const char* message) { 3486 int i; 3487 fdStream err(defaultStream::error_fd()); 3488 for (i = 0; i < 78; i++) err.print_raw("="); 3489 err.cr(); 3490 err.print_raw_cr(title); 3491 for (i = 0; i < 78; i++) err.print_raw("-"); 3492 err.cr(); 3493 err.print_raw_cr(message); 3494 for (i = 0; i < 78; i++) err.print_raw("="); 3495 err.cr(); 3496 3497 char buf[16]; 3498 // Prevent process from exiting upon "read error" without consuming all CPU 3499 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3500 3501 return buf[0] == 'y' || buf[0] == 'Y'; 3502 } 3503 3504 int os::stat(const char *path, struct stat *sbuf) { 3505 char pathbuf[MAX_PATH]; 3506 if (strlen(path) > MAX_PATH - 1) { 3507 errno = ENAMETOOLONG; 3508 return -1; 3509 } 3510 os::native_path(strcpy(pathbuf, path)); 3511 return ::stat(pathbuf, sbuf); 3512 } 3513 3514 static inline struct timespec get_mtime(const char* filename) { 3515 struct stat st; 3516 int ret = os::stat(filename, &st); 3517 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno)); 3518 #ifdef __APPLE__ 3519 return st.st_mtimespec; 3520 #else 3521 return st.st_mtim; 3522 #endif 3523 } 3524 3525 int os::compare_file_modified_times(const char* file1, const char* file2) { 3526 struct timespec filetime1 = get_mtime(file1); 3527 struct timespec filetime2 = get_mtime(file2); 3528 int diff = filetime1.tv_sec - filetime2.tv_sec; 3529 if (diff == 0) { 3530 return filetime1.tv_nsec - filetime2.tv_nsec; 3531 } 3532 return diff; 3533 } 3534 3535 // Is a (classpath) directory empty? 3536 bool os::dir_is_empty(const char* path) { 3537 DIR *dir = NULL; 3538 struct dirent *ptr; 3539 3540 dir = opendir(path); 3541 if (dir == NULL) return true; 3542 3543 // Scan the directory 3544 bool result = true; 3545 char buf[sizeof(struct dirent) + MAX_PATH]; 3546 while (result && (ptr = ::readdir(dir)) != NULL) { 3547 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3548 result = false; 3549 } 3550 } 3551 closedir(dir); 3552 return result; 3553 } 3554 3555 // This code originates from JDK's sysOpen and open64_w 3556 // from src/solaris/hpi/src/system_md.c 3557 3558 int os::open(const char *path, int oflag, int mode) { 3559 if (strlen(path) > MAX_PATH - 1) { 3560 errno = ENAMETOOLONG; 3561 return -1; 3562 } 3563 int fd; 3564 3565 fd = ::open(path, oflag, mode); 3566 if (fd == -1) return -1; 3567 3568 // If the open succeeded, the file might still be a directory 3569 { 3570 struct stat buf; 3571 int ret = ::fstat(fd, &buf); 3572 int st_mode = buf.st_mode; 3573 3574 if (ret != -1) { 3575 if ((st_mode & S_IFMT) == S_IFDIR) { 3576 errno = EISDIR; 3577 ::close(fd); 3578 return -1; 3579 } 3580 } else { 3581 ::close(fd); 3582 return -1; 3583 } 3584 } 3585 3586 // All file descriptors that are opened in the JVM and not 3587 // specifically destined for a subprocess should have the 3588 // close-on-exec flag set. If we don't set it, then careless 3rd 3589 // party native code might fork and exec without closing all 3590 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3591 // UNIXProcess.c), and this in turn might: 3592 // 3593 // - cause end-of-file to fail to be detected on some file 3594 // descriptors, resulting in mysterious hangs, or 3595 // 3596 // - might cause an fopen in the subprocess to fail on a system 3597 // suffering from bug 1085341. 3598 // 3599 // (Yes, the default setting of the close-on-exec flag is a Unix 3600 // design flaw) 3601 // 3602 // See: 3603 // 1085341: 32-bit stdio routines should support file descriptors >255 3604 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3605 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3606 // 3607 #ifdef FD_CLOEXEC 3608 { 3609 int flags = ::fcntl(fd, F_GETFD); 3610 if (flags != -1) { 3611 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3612 } 3613 } 3614 #endif 3615 3616 return fd; 3617 } 3618 3619 3620 // create binary file, rewriting existing file if required 3621 int os::create_binary_file(const char* path, bool rewrite_existing) { 3622 int oflags = O_WRONLY | O_CREAT; 3623 if (!rewrite_existing) { 3624 oflags |= O_EXCL; 3625 } 3626 return ::open(path, oflags, S_IREAD | S_IWRITE); 3627 } 3628 3629 // return current position of file pointer 3630 jlong os::current_file_offset(int fd) { 3631 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3632 } 3633 3634 // move file pointer to the specified offset 3635 jlong os::seek_to_file_offset(int fd, jlong offset) { 3636 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3637 } 3638 3639 // This code originates from JDK's sysAvailable 3640 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3641 3642 int os::available(int fd, jlong *bytes) { 3643 jlong cur, end; 3644 int mode; 3645 struct stat buf; 3646 3647 if (::fstat(fd, &buf) >= 0) { 3648 mode = buf.st_mode; 3649 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3650 int n; 3651 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3652 *bytes = n; 3653 return 1; 3654 } 3655 } 3656 } 3657 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3658 return 0; 3659 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3660 return 0; 3661 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3662 return 0; 3663 } 3664 *bytes = end - cur; 3665 return 1; 3666 } 3667 3668 // Map a block of memory. 3669 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3670 char *addr, size_t bytes, bool read_only, 3671 bool allow_exec) { 3672 int prot; 3673 int flags; 3674 3675 if (read_only) { 3676 prot = PROT_READ; 3677 flags = MAP_SHARED; 3678 } else { 3679 prot = PROT_READ | PROT_WRITE; 3680 flags = MAP_PRIVATE; 3681 } 3682 3683 if (allow_exec) { 3684 prot |= PROT_EXEC; 3685 } 3686 3687 if (addr != NULL) { 3688 flags |= MAP_FIXED; 3689 } 3690 3691 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3692 fd, file_offset); 3693 if (mapped_address == MAP_FAILED) { 3694 return NULL; 3695 } 3696 return mapped_address; 3697 } 3698 3699 3700 // Remap a block of memory. 3701 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3702 char *addr, size_t bytes, bool read_only, 3703 bool allow_exec) { 3704 // same as map_memory() on this OS 3705 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3706 allow_exec); 3707 } 3708 3709 3710 // Unmap a block of memory. 3711 bool os::pd_unmap_memory(char* addr, size_t bytes) { 3712 return munmap(addr, bytes) == 0; 3713 } 3714 3715 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3716 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 3717 // of a thread. 3718 // 3719 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 3720 // the fast estimate available on the platform. 3721 3722 jlong os::current_thread_cpu_time() { 3723 #ifdef __APPLE__ 3724 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 3725 #else 3726 Unimplemented(); 3727 return 0; 3728 #endif 3729 } 3730 3731 jlong os::thread_cpu_time(Thread* thread) { 3732 #ifdef __APPLE__ 3733 return os::thread_cpu_time(thread, true /* user + sys */); 3734 #else 3735 Unimplemented(); 3736 return 0; 3737 #endif 3738 } 3739 3740 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 3741 #ifdef __APPLE__ 3742 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 3743 #else 3744 Unimplemented(); 3745 return 0; 3746 #endif 3747 } 3748 3749 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 3750 #ifdef __APPLE__ 3751 struct thread_basic_info tinfo; 3752 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 3753 kern_return_t kr; 3754 thread_t mach_thread; 3755 3756 mach_thread = thread->osthread()->thread_id(); 3757 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 3758 if (kr != KERN_SUCCESS) { 3759 return -1; 3760 } 3761 3762 if (user_sys_cpu_time) { 3763 jlong nanos; 3764 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 3765 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 3766 return nanos; 3767 } else { 3768 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 3769 } 3770 #else 3771 Unimplemented(); 3772 return 0; 3773 #endif 3774 } 3775 3776 3777 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3778 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3779 info_ptr->may_skip_backward = false; // elapsed time not wall time 3780 info_ptr->may_skip_forward = false; // elapsed time not wall time 3781 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3782 } 3783 3784 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3785 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3786 info_ptr->may_skip_backward = false; // elapsed time not wall time 3787 info_ptr->may_skip_forward = false; // elapsed time not wall time 3788 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3789 } 3790 3791 bool os::is_thread_cpu_time_supported() { 3792 #ifdef __APPLE__ 3793 return true; 3794 #else 3795 return false; 3796 #endif 3797 } 3798 3799 // System loadavg support. Returns -1 if load average cannot be obtained. 3800 // Bsd doesn't yet have a (official) notion of processor sets, 3801 // so just return the system wide load average. 3802 int os::loadavg(double loadavg[], int nelem) { 3803 return ::getloadavg(loadavg, nelem); 3804 } 3805 3806 void os::pause() { 3807 char filename[MAX_PATH]; 3808 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 3809 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 3810 } else { 3811 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 3812 } 3813 3814 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 3815 if (fd != -1) { 3816 struct stat buf; 3817 ::close(fd); 3818 while (::stat(filename, &buf) == 0) { 3819 (void)::poll(NULL, 0, 100); 3820 } 3821 } else { 3822 jio_fprintf(stderr, 3823 "Could not open pause file '%s', continuing immediately.\n", filename); 3824 } 3825 } 3826 3827 // Darwin has no "environ" in a dynamic library. 3828 #ifdef __APPLE__ 3829 #include <crt_externs.h> 3830 #define environ (*_NSGetEnviron()) 3831 #else 3832 extern char** environ; 3833 #endif 3834 3835 // Run the specified command in a separate process. Return its exit value, 3836 // or -1 on failure (e.g. can't fork a new process). 3837 // Unlike system(), this function can be called from signal handler. It 3838 // doesn't block SIGINT et al. 3839 int os::fork_and_exec(char* cmd) { 3840 const char * argv[4] = {"sh", "-c", cmd, NULL}; 3841 3842 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 3843 // pthread_atfork handlers and reset pthread library. All we need is a 3844 // separate process to execve. Make a direct syscall to fork process. 3845 // On IA64 there's no fork syscall, we have to use fork() and hope for 3846 // the best... 3847 pid_t pid = fork(); 3848 3849 if (pid < 0) { 3850 // fork failed 3851 return -1; 3852 3853 } else if (pid == 0) { 3854 // child process 3855 3856 // execve() in BsdThreads will call pthread_kill_other_threads_np() 3857 // first to kill every thread on the thread list. Because this list is 3858 // not reset by fork() (see notes above), execve() will instead kill 3859 // every thread in the parent process. We know this is the only thread 3860 // in the new process, so make a system call directly. 3861 // IA64 should use normal execve() from glibc to match the glibc fork() 3862 // above. 3863 execve("/bin/sh", (char* const*)argv, environ); 3864 3865 // execve failed 3866 _exit(-1); 3867 3868 } else { 3869 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 3870 // care about the actual exit code, for now. 3871 3872 int status; 3873 3874 // Wait for the child process to exit. This returns immediately if 3875 // the child has already exited. */ 3876 while (waitpid(pid, &status, 0) < 0) { 3877 switch (errno) { 3878 case ECHILD: return 0; 3879 case EINTR: break; 3880 default: return -1; 3881 } 3882 } 3883 3884 if (WIFEXITED(status)) { 3885 // The child exited normally; get its exit code. 3886 return WEXITSTATUS(status); 3887 } else if (WIFSIGNALED(status)) { 3888 // The child exited because of a signal 3889 // The best value to return is 0x80 + signal number, 3890 // because that is what all Unix shells do, and because 3891 // it allows callers to distinguish between process exit and 3892 // process death by signal. 3893 return 0x80 + WTERMSIG(status); 3894 } else { 3895 // Unknown exit code; pass it through 3896 return status; 3897 } 3898 } 3899 } 3900 3901 // Get the default path to the core file 3902 // Returns the length of the string 3903 int os::get_core_path(char* buffer, size_t bufferSize) { 3904 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 3905 3906 // Truncate if theoretical string was longer than bufferSize 3907 n = MIN2(n, (int)bufferSize); 3908 3909 return n; 3910 } 3911 3912 #ifndef PRODUCT 3913 void TestReserveMemorySpecial_test() { 3914 // No tests available for this platform 3915 } 3916 #endif 3917 3918 bool os::start_debugging(char *buf, int buflen) { 3919 int len = (int)strlen(buf); 3920 char *p = &buf[len]; 3921 3922 jio_snprintf(p, buflen-len, 3923 "\n\n" 3924 "Do you want to debug the problem?\n\n" 3925 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n" 3926 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n" 3927 "Otherwise, press RETURN to abort...", 3928 os::current_process_id(), os::current_process_id(), 3929 os::current_thread_id(), os::current_thread_id()); 3930 3931 bool yes = os::message_box("Unexpected Error", buf); 3932 3933 if (yes) { 3934 // yes, user asked VM to launch debugger 3935 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d", 3936 os::current_process_id(), os::current_process_id()); 3937 3938 os::fork_and_exec(buf); 3939 yes = false; 3940 } 3941 return yes; 3942 }