1 /* 2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "classfile/classLoader.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/vmSymbols.hpp" 29 #include "code/icBuffer.hpp" 30 #include "code/vtableStubs.hpp" 31 #include "compiler/compileBroker.hpp" 32 #include "compiler/disassembler.hpp" 33 #include "interpreter/interpreter.hpp" 34 #include "jvm_bsd.h" 35 #include "memory/allocation.inline.hpp" 36 #include "memory/filemap.hpp" 37 #include "mutex_bsd.inline.hpp" 38 #include "oops/oop.inline.hpp" 39 #include "os_bsd.inline.hpp" 40 #include "os_share_bsd.hpp" 41 #include "prims/jniFastGetField.hpp" 42 #include "prims/jvm.h" 43 #include "prims/jvm_misc.hpp" 44 #include "runtime/arguments.hpp" 45 #include "runtime/atomic.inline.hpp" 46 #include "runtime/extendedPC.hpp" 47 #include "runtime/globals.hpp" 48 #include "runtime/interfaceSupport.hpp" 49 #include "runtime/java.hpp" 50 #include "runtime/javaCalls.hpp" 51 #include "runtime/mutexLocker.hpp" 52 #include "runtime/objectMonitor.hpp" 53 #include "runtime/orderAccess.inline.hpp" 54 #include "runtime/osThread.hpp" 55 #include "runtime/perfMemory.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 "semaphore_bsd.hpp" 63 #include "services/attachListener.hpp" 64 #include "services/memTracker.hpp" 65 #include "services/runtimeService.hpp" 66 #include "utilities/decoder.hpp" 67 #include "utilities/defaultStream.hpp" 68 #include "utilities/events.hpp" 69 #include "utilities/growableArray.hpp" 70 #include "utilities/vmError.hpp" 71 72 // put OS-includes here 73 # include <sys/types.h> 74 # include <sys/mman.h> 75 # include <sys/stat.h> 76 # include <sys/select.h> 77 # include <pthread.h> 78 # include <signal.h> 79 # include <errno.h> 80 # include <dlfcn.h> 81 # include <stdio.h> 82 # include <unistd.h> 83 # include <sys/resource.h> 84 # include <pthread.h> 85 # include <sys/stat.h> 86 # include <sys/time.h> 87 # include <sys/times.h> 88 # include <sys/utsname.h> 89 # include <sys/socket.h> 90 # include <sys/wait.h> 91 # include <time.h> 92 # include <pwd.h> 93 # include <poll.h> 94 # include <semaphore.h> 95 # include <fcntl.h> 96 # include <string.h> 97 # include <sys/param.h> 98 # include <sys/sysctl.h> 99 # include <sys/ipc.h> 100 # include <sys/shm.h> 101 #ifndef __APPLE__ 102 # include <link.h> 103 #endif 104 # include <stdint.h> 105 # include <inttypes.h> 106 # include <sys/ioctl.h> 107 # include <sys/syscall.h> 108 109 #if defined(__FreeBSD__) || defined(__NetBSD__) 110 #include <elf.h> 111 #endif 112 113 #ifdef __APPLE__ 114 #include <mach/mach.h> // semaphore_* API 115 #include <mach-o/dyld.h> 116 #include <sys/proc_info.h> 117 #include <objc/objc-auto.h> 118 #endif 119 120 #ifndef MAP_ANONYMOUS 121 #define MAP_ANONYMOUS MAP_ANON 122 #endif 123 124 #define MAX_PATH (2 * K) 125 126 // for timer info max values which include all bits 127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 128 129 #define LARGEPAGES_BIT (1 << 6) 130 131 //////////////////////////////////////////////////////////////////////////////// 132 // global variables 133 julong os::Bsd::_physical_memory = 0; 134 135 #ifdef __APPLE__ 136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 137 volatile uint64_t os::Bsd::_max_abstime = 0; 138 #else 139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 140 #endif 141 pthread_t os::Bsd::_main_thread; 142 int os::Bsd::_page_size = -1; 143 144 static jlong initial_time_count=0; 145 146 static int clock_tics_per_sec = 100; 147 148 // For diagnostics to print a message once. see run_periodic_checks 149 static sigset_t check_signal_done; 150 static bool check_signals = true; 151 152 static pid_t _initial_pid = 0; 153 154 // Signal number used to suspend/resume a thread 155 156 // do not use any signal number less than SIGSEGV, see 4355769 157 static int SR_signum = SIGUSR2; 158 sigset_t SR_sigset; 159 160 161 //////////////////////////////////////////////////////////////////////////////// 162 // utility functions 163 164 static int SR_initialize(); 165 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 166 167 julong os::available_memory() { 168 return Bsd::available_memory(); 169 } 170 171 // available here means free 172 julong os::Bsd::available_memory() { 173 uint64_t available = physical_memory() >> 2; 174 #ifdef __APPLE__ 175 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 176 vm_statistics64_data_t vmstat; 177 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 178 (host_info64_t)&vmstat, &count); 179 assert(kerr == KERN_SUCCESS, 180 "host_statistics64 failed - check mach_host_self() and count"); 181 if (kerr == KERN_SUCCESS) { 182 available = vmstat.free_count * os::vm_page_size(); 183 } 184 #endif 185 return available; 186 } 187 188 julong os::physical_memory() { 189 return Bsd::physical_memory(); 190 } 191 192 // Return true if user is running as root. 193 194 bool os::have_special_privileges() { 195 static bool init = false; 196 static bool privileges = false; 197 if (!init) { 198 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 199 init = true; 200 } 201 return privileges; 202 } 203 204 205 206 // Cpu architecture string 207 #if defined(ZERO) 208 static char cpu_arch[] = ZERO_LIBARCH; 209 #elif defined(IA64) 210 static char cpu_arch[] = "ia64"; 211 #elif defined(IA32) 212 static char cpu_arch[] = "i386"; 213 #elif defined(AMD64) 214 static char cpu_arch[] = "amd64"; 215 #elif defined(ARM) 216 static char cpu_arch[] = "arm"; 217 #elif defined(PPC32) 218 static char cpu_arch[] = "ppc"; 219 #elif defined(SPARC) 220 #ifdef _LP64 221 static char cpu_arch[] = "sparcv9"; 222 #else 223 static char cpu_arch[] = "sparc"; 224 #endif 225 #else 226 #error Add appropriate cpu_arch setting 227 #endif 228 229 // Compiler variant 230 #ifdef COMPILER2 231 #define COMPILER_VARIANT "server" 232 #else 233 #define COMPILER_VARIANT "client" 234 #endif 235 236 237 void os::Bsd::initialize_system_info() { 238 int mib[2]; 239 size_t len; 240 int cpu_val; 241 julong mem_val; 242 243 // get processors count via hw.ncpus sysctl 244 mib[0] = CTL_HW; 245 mib[1] = HW_NCPU; 246 len = sizeof(cpu_val); 247 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 248 assert(len == sizeof(cpu_val), "unexpected data size"); 249 set_processor_count(cpu_val); 250 } else { 251 set_processor_count(1); // fallback 252 } 253 254 // get physical memory via hw.memsize sysctl (hw.memsize is used 255 // since it returns a 64 bit value) 256 mib[0] = CTL_HW; 257 258 #if defined (HW_MEMSIZE) // Apple 259 mib[1] = HW_MEMSIZE; 260 #elif defined(HW_PHYSMEM) // Most of BSD 261 mib[1] = HW_PHYSMEM; 262 #elif defined(HW_REALMEM) // Old FreeBSD 263 mib[1] = HW_REALMEM; 264 #else 265 #error No ways to get physmem 266 #endif 267 268 len = sizeof(mem_val); 269 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 270 assert(len == sizeof(mem_val), "unexpected data size"); 271 _physical_memory = mem_val; 272 } else { 273 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 274 } 275 276 #ifdef __OpenBSD__ 277 { 278 // limit _physical_memory memory view on OpenBSD since 279 // datasize rlimit restricts us anyway. 280 struct rlimit limits; 281 getrlimit(RLIMIT_DATA, &limits); 282 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 283 } 284 #endif 285 } 286 287 #ifdef __APPLE__ 288 static const char *get_home() { 289 const char *home_dir = ::getenv("HOME"); 290 if ((home_dir == NULL) || (*home_dir == '\0')) { 291 struct passwd *passwd_info = getpwuid(geteuid()); 292 if (passwd_info != NULL) { 293 home_dir = passwd_info->pw_dir; 294 } 295 } 296 297 return home_dir; 298 } 299 #endif 300 301 void os::init_system_properties_values() { 302 // The next steps are taken in the product version: 303 // 304 // Obtain the JAVA_HOME value from the location of libjvm.so. 305 // This library should be located at: 306 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 307 // 308 // If "/jre/lib/" appears at the right place in the path, then we 309 // assume libjvm.so is installed in a JDK and we use this path. 310 // 311 // Otherwise exit with message: "Could not create the Java virtual machine." 312 // 313 // The following extra steps are taken in the debugging version: 314 // 315 // If "/jre/lib/" does NOT appear at the right place in the path 316 // instead of exit check for $JAVA_HOME environment variable. 317 // 318 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 319 // then we append a fake suffix "hotspot/libjvm.so" to this path so 320 // it looks like libjvm.so is installed there 321 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 322 // 323 // Otherwise exit. 324 // 325 // Important note: if the location of libjvm.so changes this 326 // code needs to be changed accordingly. 327 328 // See ld(1): 329 // The linker uses the following search paths to locate required 330 // shared libraries: 331 // 1: ... 332 // ... 333 // 7: The default directories, normally /lib and /usr/lib. 334 #ifndef DEFAULT_LIBPATH 335 #define DEFAULT_LIBPATH "/lib:/usr/lib" 336 #endif 337 338 // Base path of extensions installed on the system. 339 #define SYS_EXT_DIR "/usr/java/packages" 340 #define EXTENSIONS_DIR "/lib/ext" 341 342 #ifndef __APPLE__ 343 344 // Buffer that fits several sprintfs. 345 // Note that the space for the colon and the trailing null are provided 346 // by the nulls included by the sizeof operator. 347 const size_t bufsize = 348 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 349 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 350 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 351 352 // sysclasspath, java_home, dll_dir 353 { 354 char *pslash; 355 os::jvm_path(buf, bufsize); 356 357 // Found the full path to libjvm.so. 358 // Now cut the path to <java_home>/jre if we can. 359 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 360 pslash = strrchr(buf, '/'); 361 if (pslash != NULL) { 362 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 363 } 364 Arguments::set_dll_dir(buf); 365 366 if (pslash != NULL) { 367 pslash = strrchr(buf, '/'); 368 if (pslash != NULL) { 369 *pslash = '\0'; // Get rid of /<arch>. 370 pslash = strrchr(buf, '/'); 371 if (pslash != NULL) { 372 *pslash = '\0'; // Get rid of /lib. 373 } 374 } 375 } 376 Arguments::set_java_home(buf); 377 set_boot_path('/', ':'); 378 } 379 380 // Where to look for native libraries. 381 // 382 // Note: Due to a legacy implementation, most of the library path 383 // is set in the launcher. This was to accomodate linking restrictions 384 // on legacy Bsd implementations (which are no longer supported). 385 // Eventually, all the library path setting will be done here. 386 // 387 // However, to prevent the proliferation of improperly built native 388 // libraries, the new path component /usr/java/packages is added here. 389 // Eventually, all the library path setting will be done here. 390 { 391 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 392 // should always exist (until the legacy problem cited above is 393 // addressed). 394 const char *v = ::getenv("LD_LIBRARY_PATH"); 395 const char *v_colon = ":"; 396 if (v == NULL) { v = ""; v_colon = ""; } 397 // That's +1 for the colon and +1 for the trailing '\0'. 398 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 399 strlen(v) + 1 + 400 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 401 mtInternal); 402 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 403 Arguments::set_library_path(ld_library_path); 404 FREE_C_HEAP_ARRAY(char, ld_library_path); 405 } 406 407 // Extensions directories. 408 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 409 Arguments::set_ext_dirs(buf); 410 411 FREE_C_HEAP_ARRAY(char, buf); 412 413 #else // __APPLE__ 414 415 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 416 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 417 418 const char *user_home_dir = get_home(); 419 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 420 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 421 sizeof(SYS_EXTENSIONS_DIRS); 422 423 // Buffer that fits several sprintfs. 424 // Note that the space for the colon and the trailing null are provided 425 // by the nulls included by the sizeof operator. 426 const size_t bufsize = 427 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 428 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 429 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 430 431 // sysclasspath, java_home, dll_dir 432 { 433 char *pslash; 434 os::jvm_path(buf, bufsize); 435 436 // Found the full path to libjvm.so. 437 // Now cut the path to <java_home>/jre if we can. 438 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 439 pslash = strrchr(buf, '/'); 440 if (pslash != NULL) { 441 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 442 } 443 #ifdef STATIC_BUILD 444 strcat(buf, "/lib"); 445 #endif 446 447 Arguments::set_dll_dir(buf); 448 449 if (pslash != NULL) { 450 pslash = strrchr(buf, '/'); 451 if (pslash != NULL) { 452 *pslash = '\0'; // Get rid of /lib. 453 } 454 } 455 Arguments::set_java_home(buf); 456 set_boot_path('/', ':'); 457 } 458 459 // Where to look for native libraries. 460 // 461 // Note: Due to a legacy implementation, most of the library path 462 // is set in the launcher. This was to accomodate linking restrictions 463 // on legacy Bsd implementations (which are no longer supported). 464 // Eventually, all the library path setting will be done here. 465 // 466 // However, to prevent the proliferation of improperly built native 467 // libraries, the new path component /usr/java/packages is added here. 468 // Eventually, all the library path setting will be done here. 469 { 470 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 471 // should always exist (until the legacy problem cited above is 472 // addressed). 473 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 474 // can specify a directory inside an app wrapper 475 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 476 const char *l_colon = ":"; 477 if (l == NULL) { l = ""; l_colon = ""; } 478 479 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 480 const char *v_colon = ":"; 481 if (v == NULL) { v = ""; v_colon = ""; } 482 483 // Apple's Java6 has "." at the beginning of java.library.path. 484 // OpenJDK on Windows has "." at the end of java.library.path. 485 // OpenJDK on Linux and Solaris don't have "." in java.library.path 486 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 487 // "." is appended to the end of java.library.path. Yes, this 488 // could cause a change in behavior, but Apple's Java6 behavior 489 // can be achieved by putting "." at the beginning of the 490 // JAVA_LIBRARY_PATH environment variable. 491 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 492 strlen(v) + 1 + strlen(l) + 1 + 493 system_ext_size + 3, 494 mtInternal); 495 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 496 v, v_colon, l, l_colon, user_home_dir); 497 Arguments::set_library_path(ld_library_path); 498 FREE_C_HEAP_ARRAY(char, ld_library_path); 499 } 500 501 // Extensions directories. 502 // 503 // Note that the space for the colon and the trailing null are provided 504 // by the nulls included by the sizeof operator (so actually one byte more 505 // than necessary is allocated). 506 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 507 user_home_dir, Arguments::get_java_home()); 508 Arguments::set_ext_dirs(buf); 509 510 FREE_C_HEAP_ARRAY(char, buf); 511 512 #undef SYS_EXTENSIONS_DIR 513 #undef SYS_EXTENSIONS_DIRS 514 515 #endif // __APPLE__ 516 517 #undef SYS_EXT_DIR 518 #undef EXTENSIONS_DIR 519 } 520 521 //////////////////////////////////////////////////////////////////////////////// 522 // breakpoint support 523 524 void os::breakpoint() { 525 BREAKPOINT; 526 } 527 528 extern "C" void breakpoint() { 529 // use debugger to set breakpoint here 530 } 531 532 //////////////////////////////////////////////////////////////////////////////// 533 // signal support 534 535 debug_only(static bool signal_sets_initialized = false); 536 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 537 538 bool os::Bsd::is_sig_ignored(int sig) { 539 struct sigaction oact; 540 sigaction(sig, (struct sigaction*)NULL, &oact); 541 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 542 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 543 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) { 544 return true; 545 } else { 546 return false; 547 } 548 } 549 550 void os::Bsd::signal_sets_init() { 551 // Should also have an assertion stating we are still single-threaded. 552 assert(!signal_sets_initialized, "Already initialized"); 553 // Fill in signals that are necessarily unblocked for all threads in 554 // the VM. Currently, we unblock the following signals: 555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 556 // by -Xrs (=ReduceSignalUsage)); 557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 559 // the dispositions or masks wrt these signals. 560 // Programs embedding the VM that want to use the above signals for their 561 // own purposes must, at this time, use the "-Xrs" option to prevent 562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 563 // (See bug 4345157, and other related bugs). 564 // In reality, though, unblocking these signals is really a nop, since 565 // these signals are not blocked by default. 566 sigemptyset(&unblocked_sigs); 567 sigemptyset(&allowdebug_blocked_sigs); 568 sigaddset(&unblocked_sigs, SIGILL); 569 sigaddset(&unblocked_sigs, SIGSEGV); 570 sigaddset(&unblocked_sigs, SIGBUS); 571 sigaddset(&unblocked_sigs, SIGFPE); 572 sigaddset(&unblocked_sigs, SR_signum); 573 574 if (!ReduceSignalUsage) { 575 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 576 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 577 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 578 } 579 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 580 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 581 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 582 } 583 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 584 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 585 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 586 } 587 } 588 // Fill in signals that are blocked by all but the VM thread. 589 sigemptyset(&vm_sigs); 590 if (!ReduceSignalUsage) { 591 sigaddset(&vm_sigs, BREAK_SIGNAL); 592 } 593 debug_only(signal_sets_initialized = true); 594 595 } 596 597 // These are signals that are unblocked while a thread is running Java. 598 // (For some reason, they get blocked by default.) 599 sigset_t* os::Bsd::unblocked_signals() { 600 assert(signal_sets_initialized, "Not initialized"); 601 return &unblocked_sigs; 602 } 603 604 // These are the signals that are blocked while a (non-VM) thread is 605 // running Java. Only the VM thread handles these signals. 606 sigset_t* os::Bsd::vm_signals() { 607 assert(signal_sets_initialized, "Not initialized"); 608 return &vm_sigs; 609 } 610 611 // These are signals that are blocked during cond_wait to allow debugger in 612 sigset_t* os::Bsd::allowdebug_blocked_signals() { 613 assert(signal_sets_initialized, "Not initialized"); 614 return &allowdebug_blocked_sigs; 615 } 616 617 void os::Bsd::hotspot_sigmask(Thread* thread) { 618 619 //Save caller's signal mask before setting VM signal mask 620 sigset_t caller_sigmask; 621 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 622 623 OSThread* osthread = thread->osthread(); 624 osthread->set_caller_sigmask(caller_sigmask); 625 626 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 627 628 if (!ReduceSignalUsage) { 629 if (thread->is_VM_thread()) { 630 // Only the VM thread handles BREAK_SIGNAL ... 631 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 632 } else { 633 // ... all other threads block BREAK_SIGNAL 634 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 635 } 636 } 637 } 638 639 640 ////////////////////////////////////////////////////////////////////////////// 641 // create new thread 642 643 #ifdef __APPLE__ 644 // library handle for calling objc_registerThreadWithCollector() 645 // without static linking to the libobjc library 646 #define OBJC_LIB "/usr/lib/libobjc.dylib" 647 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 648 typedef void (*objc_registerThreadWithCollector_t)(); 649 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 650 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 651 #endif 652 653 #ifdef __APPLE__ 654 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 655 // Additional thread_id used to correlate threads in SA 656 thread_identifier_info_data_t m_ident_info; 657 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 658 659 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 660 (thread_info_t) &m_ident_info, &count); 661 662 return m_ident_info.thread_id; 663 } 664 #endif 665 666 // Thread start routine for all newly created threads 667 static void *java_start(Thread *thread) { 668 // Try to randomize the cache line index of hot stack frames. 669 // This helps when threads of the same stack traces evict each other's 670 // cache lines. The threads can be either from the same JVM instance, or 671 // from different JVM instances. The benefit is especially true for 672 // processors with hyperthreading technology. 673 static int counter = 0; 674 int pid = os::current_process_id(); 675 alloca(((pid ^ counter++) & 7) * 128); 676 677 ThreadLocalStorage::set_thread(thread); 678 679 OSThread* osthread = thread->osthread(); 680 Monitor* sync = osthread->startThread_lock(); 681 682 osthread->set_thread_id(os::Bsd::gettid()); 683 684 #ifdef __APPLE__ 685 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 686 guarantee(unique_thread_id != 0, "unique thread id was not found"); 687 osthread->set_unique_thread_id(unique_thread_id); 688 #endif 689 // initialize signal mask for this thread 690 os::Bsd::hotspot_sigmask(thread); 691 692 // initialize floating point control register 693 os::Bsd::init_thread_fpu_state(); 694 695 #ifdef __APPLE__ 696 // register thread with objc gc 697 if (objc_registerThreadWithCollectorFunction != NULL) { 698 objc_registerThreadWithCollectorFunction(); 699 } 700 #endif 701 702 // handshaking with parent thread 703 { 704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 705 706 // notify parent thread 707 osthread->set_state(INITIALIZED); 708 sync->notify_all(); 709 710 // wait until os::start_thread() 711 while (osthread->get_state() == INITIALIZED) { 712 sync->wait(Mutex::_no_safepoint_check_flag); 713 } 714 } 715 716 // call one more level start routine 717 thread->run(); 718 719 return 0; 720 } 721 722 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 723 assert(thread->osthread() == NULL, "caller responsible"); 724 725 // Allocate the OSThread object 726 OSThread* osthread = new OSThread(NULL, NULL); 727 if (osthread == NULL) { 728 return false; 729 } 730 731 // set the correct thread state 732 osthread->set_thread_type(thr_type); 733 734 // Initial state is ALLOCATED but not INITIALIZED 735 osthread->set_state(ALLOCATED); 736 737 thread->set_osthread(osthread); 738 739 // init thread attributes 740 pthread_attr_t attr; 741 pthread_attr_init(&attr); 742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 743 744 // calculate stack size if it's not specified by caller 745 if (stack_size == 0) { 746 stack_size = os::Bsd::default_stack_size(thr_type); 747 748 switch (thr_type) { 749 case os::java_thread: 750 // Java threads use ThreadStackSize which default value can be 751 // changed with the flag -Xss 752 assert(JavaThread::stack_size_at_create() > 0, "this should be set"); 753 stack_size = JavaThread::stack_size_at_create(); 754 break; 755 case os::compiler_thread: 756 if (CompilerThreadStackSize > 0) { 757 stack_size = (size_t)(CompilerThreadStackSize * K); 758 break; 759 } // else fall through: 760 // use VMThreadStackSize if CompilerThreadStackSize is not defined 761 case os::vm_thread: 762 case os::pgc_thread: 763 case os::cgc_thread: 764 case os::watcher_thread: 765 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 766 break; 767 } 768 } 769 770 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 771 pthread_attr_setstacksize(&attr, stack_size); 772 773 ThreadState state; 774 775 { 776 pthread_t tid; 777 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 778 779 pthread_attr_destroy(&attr); 780 781 if (ret != 0) { 782 if (PrintMiscellaneous && (Verbose || WizardMode)) { 783 perror("pthread_create()"); 784 } 785 // Need to clean up stuff we've allocated so far 786 thread->set_osthread(NULL); 787 delete osthread; 788 return false; 789 } 790 791 // Store pthread info into the OSThread 792 osthread->set_pthread_id(tid); 793 794 // Wait until child thread is either initialized or aborted 795 { 796 Monitor* sync_with_child = osthread->startThread_lock(); 797 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 798 while ((state = osthread->get_state()) == ALLOCATED) { 799 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 800 } 801 } 802 803 } 804 805 // Aborted due to thread limit being reached 806 if (state == ZOMBIE) { 807 thread->set_osthread(NULL); 808 delete osthread; 809 return false; 810 } 811 812 // The thread is returned suspended (in state INITIALIZED), 813 // and is started higher up in the call chain 814 assert(state == INITIALIZED, "race condition"); 815 return true; 816 } 817 818 ///////////////////////////////////////////////////////////////////////////// 819 // attach existing thread 820 821 // bootstrap the main thread 822 bool os::create_main_thread(JavaThread* thread) { 823 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 824 return create_attached_thread(thread); 825 } 826 827 bool os::create_attached_thread(JavaThread* thread) { 828 #ifdef ASSERT 829 thread->verify_not_published(); 830 #endif 831 832 // Allocate the OSThread object 833 OSThread* osthread = new OSThread(NULL, NULL); 834 835 if (osthread == NULL) { 836 return false; 837 } 838 839 osthread->set_thread_id(os::Bsd::gettid()); 840 841 // Store pthread info into the OSThread 842 #ifdef __APPLE__ 843 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 844 guarantee(unique_thread_id != 0, "just checking"); 845 osthread->set_unique_thread_id(unique_thread_id); 846 #endif 847 osthread->set_pthread_id(::pthread_self()); 848 849 // initialize floating point control register 850 os::Bsd::init_thread_fpu_state(); 851 852 // Initial thread state is RUNNABLE 853 osthread->set_state(RUNNABLE); 854 855 thread->set_osthread(osthread); 856 857 // initialize signal mask for this thread 858 // and save the caller's signal mask 859 os::Bsd::hotspot_sigmask(thread); 860 861 return true; 862 } 863 864 void os::pd_start_thread(Thread* thread) { 865 OSThread * osthread = thread->osthread(); 866 assert(osthread->get_state() != INITIALIZED, "just checking"); 867 Monitor* sync_with_child = osthread->startThread_lock(); 868 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 869 sync_with_child->notify(); 870 } 871 872 // Free Bsd resources related to the OSThread 873 void os::free_thread(OSThread* osthread) { 874 assert(osthread != NULL, "osthread not set"); 875 876 if (Thread::current()->osthread() == osthread) { 877 // Restore caller's signal mask 878 sigset_t sigmask = osthread->caller_sigmask(); 879 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 880 } 881 882 delete osthread; 883 } 884 885 ////////////////////////////////////////////////////////////////////////////// 886 // thread local storage 887 888 // Restore the thread pointer if the destructor is called. This is in case 889 // someone from JNI code sets up a destructor with pthread_key_create to run 890 // detachCurrentThread on thread death. Unless we restore the thread pointer we 891 // will hang or crash. When detachCurrentThread is called the key will be set 892 // to null and we will not be called again. If detachCurrentThread is never 893 // called we could loop forever depending on the pthread implementation. 894 static void restore_thread_pointer(void* p) { 895 Thread* thread = (Thread*) p; 896 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread); 897 } 898 899 int os::allocate_thread_local_storage() { 900 pthread_key_t key; 901 int rslt = pthread_key_create(&key, restore_thread_pointer); 902 assert(rslt == 0, "cannot allocate thread local storage"); 903 return (int)key; 904 } 905 906 // Note: This is currently not used by VM, as we don't destroy TLS key 907 // on VM exit. 908 void os::free_thread_local_storage(int index) { 909 int rslt = pthread_key_delete((pthread_key_t)index); 910 assert(rslt == 0, "invalid index"); 911 } 912 913 void os::thread_local_storage_at_put(int index, void* value) { 914 int rslt = pthread_setspecific((pthread_key_t)index, value); 915 assert(rslt == 0, "pthread_setspecific failed"); 916 } 917 918 extern "C" Thread* get_thread() { 919 return ThreadLocalStorage::thread(); 920 } 921 922 923 //////////////////////////////////////////////////////////////////////////////// 924 // time support 925 926 // Time since start-up in seconds to a fine granularity. 927 // Used by VMSelfDestructTimer and the MemProfiler. 928 double os::elapsedTime() { 929 930 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 931 } 932 933 jlong os::elapsed_counter() { 934 return javaTimeNanos() - initial_time_count; 935 } 936 937 jlong os::elapsed_frequency() { 938 return NANOSECS_PER_SEC; // nanosecond resolution 939 } 940 941 bool os::supports_vtime() { return true; } 942 bool os::enable_vtime() { return false; } 943 bool os::vtime_enabled() { return false; } 944 945 double os::elapsedVTime() { 946 // better than nothing, but not much 947 return elapsedTime(); 948 } 949 950 jlong os::javaTimeMillis() { 951 timeval time; 952 int status = gettimeofday(&time, NULL); 953 assert(status != -1, "bsd error"); 954 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 955 } 956 957 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 958 timeval time; 959 int status = gettimeofday(&time, NULL); 960 assert(status != -1, "bsd error"); 961 seconds = jlong(time.tv_sec); 962 nanos = jlong(time.tv_usec) * 1000; 963 } 964 965 #ifndef __APPLE__ 966 #ifndef CLOCK_MONOTONIC 967 #define CLOCK_MONOTONIC (1) 968 #endif 969 #endif 970 971 #ifdef __APPLE__ 972 void os::Bsd::clock_init() { 973 mach_timebase_info(&_timebase_info); 974 } 975 #else 976 void os::Bsd::clock_init() { 977 struct timespec res; 978 struct timespec tp; 979 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 980 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 981 // yes, monotonic clock is supported 982 _clock_gettime = ::clock_gettime; 983 } 984 } 985 #endif 986 987 988 989 #ifdef __APPLE__ 990 991 jlong os::javaTimeNanos() { 992 const uint64_t tm = mach_absolute_time(); 993 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 994 const uint64_t prev = Bsd::_max_abstime; 995 if (now <= prev) { 996 return prev; // same or retrograde time; 997 } 998 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 999 assert(obsv >= prev, "invariant"); // Monotonicity 1000 // If the CAS succeeded then we're done and return "now". 1001 // If the CAS failed and the observed value "obsv" is >= now then 1002 // we should return "obsv". If the CAS failed and now > obsv > prv then 1003 // some other thread raced this thread and installed a new value, in which case 1004 // we could either (a) retry the entire operation, (b) retry trying to install now 1005 // or (c) just return obsv. We use (c). No loop is required although in some cases 1006 // we might discard a higher "now" value in deference to a slightly lower but freshly 1007 // installed obsv value. That's entirely benign -- it admits no new orderings compared 1008 // to (a) or (b) -- and greatly reduces coherence traffic. 1009 // We might also condition (c) on the magnitude of the delta between obsv and now. 1010 // Avoiding excessive CAS operations to hot RW locations is critical. 1011 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 1012 return (prev == obsv) ? now : obsv; 1013 } 1014 1015 #else // __APPLE__ 1016 1017 jlong os::javaTimeNanos() { 1018 if (os::supports_monotonic_clock()) { 1019 struct timespec tp; 1020 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 1021 assert(status == 0, "gettime error"); 1022 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1023 return result; 1024 } else { 1025 timeval time; 1026 int status = gettimeofday(&time, NULL); 1027 assert(status != -1, "bsd error"); 1028 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1029 return 1000 * usecs; 1030 } 1031 } 1032 1033 #endif // __APPLE__ 1034 1035 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1036 if (os::supports_monotonic_clock()) { 1037 info_ptr->max_value = ALL_64_BITS; 1038 1039 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1040 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1041 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1042 } else { 1043 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1044 info_ptr->max_value = ALL_64_BITS; 1045 1046 // gettimeofday is a real time clock so it skips 1047 info_ptr->may_skip_backward = true; 1048 info_ptr->may_skip_forward = true; 1049 } 1050 1051 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1052 } 1053 1054 // Return the real, user, and system times in seconds from an 1055 // arbitrary fixed point in the past. 1056 bool os::getTimesSecs(double* process_real_time, 1057 double* process_user_time, 1058 double* process_system_time) { 1059 struct tms ticks; 1060 clock_t real_ticks = times(&ticks); 1061 1062 if (real_ticks == (clock_t) (-1)) { 1063 return false; 1064 } else { 1065 double ticks_per_second = (double) clock_tics_per_sec; 1066 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1067 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1068 *process_real_time = ((double) real_ticks) / ticks_per_second; 1069 1070 return true; 1071 } 1072 } 1073 1074 1075 char * os::local_time_string(char *buf, size_t buflen) { 1076 struct tm t; 1077 time_t long_time; 1078 time(&long_time); 1079 localtime_r(&long_time, &t); 1080 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1081 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1082 t.tm_hour, t.tm_min, t.tm_sec); 1083 return buf; 1084 } 1085 1086 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1087 return localtime_r(clock, res); 1088 } 1089 1090 //////////////////////////////////////////////////////////////////////////////// 1091 // runtime exit support 1092 1093 // Note: os::shutdown() might be called very early during initialization, or 1094 // called from signal handler. Before adding something to os::shutdown(), make 1095 // sure it is async-safe and can handle partially initialized VM. 1096 void os::shutdown() { 1097 1098 // allow PerfMemory to attempt cleanup of any persistent resources 1099 perfMemory_exit(); 1100 1101 // needs to remove object in file system 1102 AttachListener::abort(); 1103 1104 // flush buffered output, finish log files 1105 ostream_abort(); 1106 1107 // Check for abort hook 1108 abort_hook_t abort_hook = Arguments::abort_hook(); 1109 if (abort_hook != NULL) { 1110 abort_hook(); 1111 } 1112 1113 } 1114 1115 // Note: os::abort() might be called very early during initialization, or 1116 // called from signal handler. Before adding something to os::abort(), make 1117 // sure it is async-safe and can handle partially initialized VM. 1118 void os::abort(bool dump_core, void* siginfo, void* context) { 1119 os::shutdown(); 1120 if (dump_core) { 1121 #ifndef PRODUCT 1122 fdStream out(defaultStream::output_fd()); 1123 out.print_raw("Current thread is "); 1124 char buf[16]; 1125 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1126 out.print_raw_cr(buf); 1127 out.print_raw_cr("Dumping core ..."); 1128 #endif 1129 ::abort(); // dump core 1130 } 1131 1132 ::exit(1); 1133 } 1134 1135 // Die immediately, no exit hook, no abort hook, no cleanup. 1136 void os::die() { 1137 // _exit() on BsdThreads only kills current thread 1138 ::abort(); 1139 } 1140 1141 // This method is a copy of JDK's sysGetLastErrorString 1142 // from src/solaris/hpi/src/system_md.c 1143 1144 size_t os::lasterror(char *buf, size_t len) { 1145 if (errno == 0) return 0; 1146 1147 const char *s = ::strerror(errno); 1148 size_t n = ::strlen(s); 1149 if (n >= len) { 1150 n = len - 1; 1151 } 1152 ::strncpy(buf, s, n); 1153 buf[n] = '\0'; 1154 return n; 1155 } 1156 1157 // Information of current thread in variety of formats 1158 pid_t os::Bsd::gettid() { 1159 int retval = -1; 1160 1161 #ifdef __APPLE__ //XNU kernel 1162 // despite the fact mach port is actually not a thread id use it 1163 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1164 retval = ::pthread_mach_thread_np(::pthread_self()); 1165 guarantee(retval != 0, "just checking"); 1166 return retval; 1167 1168 #else 1169 #ifdef __FreeBSD__ 1170 retval = syscall(SYS_thr_self); 1171 #else 1172 #ifdef __OpenBSD__ 1173 retval = syscall(SYS_getthrid); 1174 #else 1175 #ifdef __NetBSD__ 1176 retval = (pid_t) syscall(SYS__lwp_self); 1177 #endif 1178 #endif 1179 #endif 1180 #endif 1181 1182 if (retval == -1) { 1183 return getpid(); 1184 } 1185 } 1186 1187 intx os::current_thread_id() { 1188 #ifdef __APPLE__ 1189 return (intx)::pthread_mach_thread_np(::pthread_self()); 1190 #else 1191 return (intx)::pthread_self(); 1192 #endif 1193 } 1194 1195 int os::current_process_id() { 1196 1197 // Under the old bsd thread library, bsd gives each thread 1198 // its own process id. Because of this each thread will return 1199 // a different pid if this method were to return the result 1200 // of getpid(2). Bsd provides no api that returns the pid 1201 // of the launcher thread for the vm. This implementation 1202 // returns a unique pid, the pid of the launcher thread 1203 // that starts the vm 'process'. 1204 1205 // Under the NPTL, getpid() returns the same pid as the 1206 // launcher thread rather than a unique pid per thread. 1207 // Use gettid() if you want the old pre NPTL behaviour. 1208 1209 // if you are looking for the result of a call to getpid() that 1210 // returns a unique pid for the calling thread, then look at the 1211 // OSThread::thread_id() method in osThread_bsd.hpp file 1212 1213 return (int)(_initial_pid ? _initial_pid : getpid()); 1214 } 1215 1216 // DLL functions 1217 1218 #define JNI_LIB_PREFIX "lib" 1219 #ifdef __APPLE__ 1220 #define JNI_LIB_SUFFIX ".dylib" 1221 #else 1222 #define JNI_LIB_SUFFIX ".so" 1223 #endif 1224 1225 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1226 1227 // This must be hard coded because it's the system's temporary 1228 // directory not the java application's temp directory, ala java.io.tmpdir. 1229 #ifdef __APPLE__ 1230 // macosx has a secure per-user temporary directory 1231 char temp_path_storage[PATH_MAX]; 1232 const char* os::get_temp_directory() { 1233 static char *temp_path = NULL; 1234 if (temp_path == NULL) { 1235 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1236 if (pathSize == 0 || pathSize > PATH_MAX) { 1237 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1238 } 1239 temp_path = temp_path_storage; 1240 } 1241 return temp_path; 1242 } 1243 #else // __APPLE__ 1244 const char* os::get_temp_directory() { return "/tmp"; } 1245 #endif // __APPLE__ 1246 1247 static bool file_exists(const char* filename) { 1248 struct stat statbuf; 1249 if (filename == NULL || strlen(filename) == 0) { 1250 return false; 1251 } 1252 return os::stat(filename, &statbuf) == 0; 1253 } 1254 1255 bool os::dll_build_name(char* buffer, size_t buflen, 1256 const char* pname, const char* fname) { 1257 bool retval = false; 1258 // Copied from libhpi 1259 const size_t pnamelen = pname ? strlen(pname) : 0; 1260 1261 // Return error on buffer overflow. 1262 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1263 return retval; 1264 } 1265 1266 if (pnamelen == 0) { 1267 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1268 retval = true; 1269 } else if (strchr(pname, *os::path_separator()) != NULL) { 1270 int n; 1271 char** pelements = split_path(pname, &n); 1272 if (pelements == NULL) { 1273 return false; 1274 } 1275 for (int i = 0; i < n; i++) { 1276 // Really shouldn't be NULL, but check can't hurt 1277 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1278 continue; // skip the empty path values 1279 } 1280 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1281 pelements[i], fname); 1282 if (file_exists(buffer)) { 1283 retval = true; 1284 break; 1285 } 1286 } 1287 // release the storage 1288 for (int i = 0; i < n; i++) { 1289 if (pelements[i] != NULL) { 1290 FREE_C_HEAP_ARRAY(char, pelements[i]); 1291 } 1292 } 1293 if (pelements != NULL) { 1294 FREE_C_HEAP_ARRAY(char*, pelements); 1295 } 1296 } else { 1297 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1298 retval = true; 1299 } 1300 return retval; 1301 } 1302 1303 // check if addr is inside libjvm.so 1304 bool os::address_is_in_vm(address addr) { 1305 static address libjvm_base_addr; 1306 Dl_info dlinfo; 1307 1308 if (libjvm_base_addr == NULL) { 1309 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1310 libjvm_base_addr = (address)dlinfo.dli_fbase; 1311 } 1312 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1313 } 1314 1315 if (dladdr((void *)addr, &dlinfo) != 0) { 1316 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1317 } 1318 1319 return false; 1320 } 1321 1322 1323 #define MACH_MAXSYMLEN 256 1324 1325 bool os::dll_address_to_function_name(address addr, char *buf, 1326 int buflen, int *offset, 1327 bool demangle) { 1328 // buf is not optional, but offset is optional 1329 assert(buf != NULL, "sanity check"); 1330 1331 Dl_info dlinfo; 1332 char localbuf[MACH_MAXSYMLEN]; 1333 1334 if (dladdr((void*)addr, &dlinfo) != 0) { 1335 // see if we have a matching symbol 1336 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1337 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) { 1338 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1339 } 1340 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1341 return true; 1342 } 1343 // no matching symbol so try for just file info 1344 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1345 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1346 buf, buflen, offset, dlinfo.dli_fname, demangle)) { 1347 return true; 1348 } 1349 } 1350 1351 // Handle non-dynamic manually: 1352 if (dlinfo.dli_fbase != NULL && 1353 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1354 dlinfo.dli_fbase)) { 1355 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) { 1356 jio_snprintf(buf, buflen, "%s", localbuf); 1357 } 1358 return true; 1359 } 1360 } 1361 buf[0] = '\0'; 1362 if (offset != NULL) *offset = -1; 1363 return false; 1364 } 1365 1366 // ported from solaris version 1367 bool os::dll_address_to_library_name(address addr, char* buf, 1368 int buflen, int* offset) { 1369 // buf is not optional, but offset is optional 1370 assert(buf != NULL, "sanity check"); 1371 1372 Dl_info dlinfo; 1373 1374 if (dladdr((void*)addr, &dlinfo) != 0) { 1375 if (dlinfo.dli_fname != NULL) { 1376 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1377 } 1378 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1379 *offset = addr - (address)dlinfo.dli_fbase; 1380 } 1381 return true; 1382 } 1383 1384 buf[0] = '\0'; 1385 if (offset) *offset = -1; 1386 return false; 1387 } 1388 1389 // Loads .dll/.so and 1390 // in case of error it checks if .dll/.so was built for the 1391 // same architecture as Hotspot is running on 1392 1393 #ifdef __APPLE__ 1394 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1395 #ifdef STATIC_BUILD 1396 return os::get_default_process_handle(); 1397 #else 1398 void * result= ::dlopen(filename, RTLD_LAZY); 1399 if (result != NULL) { 1400 // Successful loading 1401 return result; 1402 } 1403 1404 // Read system error message into ebuf 1405 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1406 ebuf[ebuflen-1]='\0'; 1407 1408 return NULL; 1409 #endif // STATIC_BUILD 1410 } 1411 #else 1412 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1413 #ifdef STATIC_BUILD 1414 return os::get_default_process_handle(); 1415 #else 1416 void * result= ::dlopen(filename, RTLD_LAZY); 1417 if (result != NULL) { 1418 // Successful loading 1419 return result; 1420 } 1421 1422 Elf32_Ehdr elf_head; 1423 1424 // Read system error message into ebuf 1425 // It may or may not be overwritten below 1426 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1427 ebuf[ebuflen-1]='\0'; 1428 int diag_msg_max_length=ebuflen-strlen(ebuf); 1429 char* diag_msg_buf=ebuf+strlen(ebuf); 1430 1431 if (diag_msg_max_length==0) { 1432 // No more space in ebuf for additional diagnostics message 1433 return NULL; 1434 } 1435 1436 1437 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1438 1439 if (file_descriptor < 0) { 1440 // Can't open library, report dlerror() message 1441 return NULL; 1442 } 1443 1444 bool failed_to_read_elf_head= 1445 (sizeof(elf_head)!= 1446 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1447 1448 ::close(file_descriptor); 1449 if (failed_to_read_elf_head) { 1450 // file i/o error - report dlerror() msg 1451 return NULL; 1452 } 1453 1454 typedef struct { 1455 Elf32_Half code; // Actual value as defined in elf.h 1456 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1457 char elf_class; // 32 or 64 bit 1458 char endianess; // MSB or LSB 1459 char* name; // String representation 1460 } arch_t; 1461 1462 #ifndef EM_486 1463 #define EM_486 6 /* Intel 80486 */ 1464 #endif 1465 1466 #ifndef EM_MIPS_RS3_LE 1467 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1468 #endif 1469 1470 #ifndef EM_PPC64 1471 #define EM_PPC64 21 /* PowerPC64 */ 1472 #endif 1473 1474 #ifndef EM_S390 1475 #define EM_S390 22 /* IBM System/390 */ 1476 #endif 1477 1478 #ifndef EM_IA_64 1479 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1480 #endif 1481 1482 #ifndef EM_X86_64 1483 #define EM_X86_64 62 /* AMD x86-64 */ 1484 #endif 1485 1486 static const arch_t arch_array[]={ 1487 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1488 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1489 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1490 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1491 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1492 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1493 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1494 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1495 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1496 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1497 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1498 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1499 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1500 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1501 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1502 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1503 }; 1504 1505 #if (defined IA32) 1506 static Elf32_Half running_arch_code=EM_386; 1507 #elif (defined AMD64) 1508 static Elf32_Half running_arch_code=EM_X86_64; 1509 #elif (defined IA64) 1510 static Elf32_Half running_arch_code=EM_IA_64; 1511 #elif (defined __sparc) && (defined _LP64) 1512 static Elf32_Half running_arch_code=EM_SPARCV9; 1513 #elif (defined __sparc) && (!defined _LP64) 1514 static Elf32_Half running_arch_code=EM_SPARC; 1515 #elif (defined __powerpc64__) 1516 static Elf32_Half running_arch_code=EM_PPC64; 1517 #elif (defined __powerpc__) 1518 static Elf32_Half running_arch_code=EM_PPC; 1519 #elif (defined ARM) 1520 static Elf32_Half running_arch_code=EM_ARM; 1521 #elif (defined S390) 1522 static Elf32_Half running_arch_code=EM_S390; 1523 #elif (defined ALPHA) 1524 static Elf32_Half running_arch_code=EM_ALPHA; 1525 #elif (defined MIPSEL) 1526 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1527 #elif (defined PARISC) 1528 static Elf32_Half running_arch_code=EM_PARISC; 1529 #elif (defined MIPS) 1530 static Elf32_Half running_arch_code=EM_MIPS; 1531 #elif (defined M68K) 1532 static Elf32_Half running_arch_code=EM_68K; 1533 #else 1534 #error Method os::dll_load requires that one of following is defined:\ 1535 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1536 #endif 1537 1538 // Identify compatability class for VM's architecture and library's architecture 1539 // Obtain string descriptions for architectures 1540 1541 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1542 int running_arch_index=-1; 1543 1544 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1545 if (running_arch_code == arch_array[i].code) { 1546 running_arch_index = i; 1547 } 1548 if (lib_arch.code == arch_array[i].code) { 1549 lib_arch.compat_class = arch_array[i].compat_class; 1550 lib_arch.name = arch_array[i].name; 1551 } 1552 } 1553 1554 assert(running_arch_index != -1, 1555 "Didn't find running architecture code (running_arch_code) in arch_array"); 1556 if (running_arch_index == -1) { 1557 // Even though running architecture detection failed 1558 // we may still continue with reporting dlerror() message 1559 return NULL; 1560 } 1561 1562 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1563 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1564 return NULL; 1565 } 1566 1567 #ifndef S390 1568 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1569 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1570 return NULL; 1571 } 1572 #endif // !S390 1573 1574 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1575 if (lib_arch.name!=NULL) { 1576 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1577 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1578 lib_arch.name, arch_array[running_arch_index].name); 1579 } else { 1580 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1581 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1582 lib_arch.code, 1583 arch_array[running_arch_index].name); 1584 } 1585 } 1586 1587 return NULL; 1588 #endif // STATIC_BUILD 1589 } 1590 #endif // !__APPLE__ 1591 1592 void* os::get_default_process_handle() { 1593 #ifdef __APPLE__ 1594 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1595 // to avoid finding unexpected symbols on second (or later) 1596 // loads of a library. 1597 return (void*)::dlopen(NULL, RTLD_FIRST); 1598 #else 1599 return (void*)::dlopen(NULL, RTLD_LAZY); 1600 #endif 1601 } 1602 1603 // XXX: Do we need a lock around this as per Linux? 1604 void* os::dll_lookup(void* handle, const char* name) { 1605 return dlsym(handle, name); 1606 } 1607 1608 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1609 outputStream * out = (outputStream *) param; 1610 out->print_cr(PTR_FORMAT " \t%s", base_address, name); 1611 return 0; 1612 } 1613 1614 void os::print_dll_info(outputStream *st) { 1615 st->print_cr("Dynamic libraries:"); 1616 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1617 st->print_cr("Error: Cannot print dynamic libraries."); 1618 } 1619 } 1620 1621 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1622 #ifdef RTLD_DI_LINKMAP 1623 Dl_info dli; 1624 void *handle; 1625 Link_map *map; 1626 Link_map *p; 1627 1628 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1629 dli.dli_fname == NULL) { 1630 return 1; 1631 } 1632 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1633 if (handle == NULL) { 1634 return 1; 1635 } 1636 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1637 if (map == NULL) { 1638 dlclose(handle); 1639 return 1; 1640 } 1641 1642 while (map->l_prev != NULL) 1643 map = map->l_prev; 1644 1645 while (map != NULL) { 1646 // Value for top_address is returned as 0 since we don't have any information about module size 1647 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1648 dlclose(handle); 1649 return 1; 1650 } 1651 map = map->l_next; 1652 } 1653 1654 dlclose(handle); 1655 #elif defined(__APPLE__) 1656 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1657 // Value for top_address is returned as 0 since we don't have any information about module size 1658 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1659 return 1; 1660 } 1661 } 1662 return 0; 1663 #else 1664 return 1; 1665 #endif 1666 } 1667 1668 void os::get_summary_os_info(char* buf, size_t buflen) { 1669 // These buffers are small because we want this to be brief 1670 // and not use a lot of stack while generating the hs_err file. 1671 char os[100]; 1672 size_t size = sizeof(os); 1673 int mib_kern[] = { CTL_KERN, KERN_OSTYPE }; 1674 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) { 1675 #ifdef __APPLE__ 1676 strncpy(os, "Darwin", sizeof(os)); 1677 #elif __OpenBSD__ 1678 strncpy(os, "OpenBSD", sizeof(os)); 1679 #else 1680 strncpy(os, "BSD", sizeof(os)); 1681 #endif 1682 } 1683 1684 char release[100]; 1685 size = sizeof(release); 1686 int mib_release[] = { CTL_KERN, KERN_OSRELEASE }; 1687 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) { 1688 // if error, leave blank 1689 strncpy(release, "", sizeof(release)); 1690 } 1691 snprintf(buf, buflen, "%s %s", os, release); 1692 } 1693 1694 void os::print_os_info_brief(outputStream* st) { 1695 os::Posix::print_uname_info(st); 1696 } 1697 1698 void os::print_os_info(outputStream* st) { 1699 st->print("OS:"); 1700 1701 os::Posix::print_uname_info(st); 1702 1703 os::Posix::print_rlimit_info(st); 1704 1705 os::Posix::print_load_average(st); 1706 } 1707 1708 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) { 1709 // Nothing to do for now. 1710 } 1711 1712 void os::get_summary_cpu_info(char* buf, size_t buflen) { 1713 unsigned int mhz; 1714 size_t size = sizeof(mhz); 1715 int mib[] = { CTL_HW, HW_CPU_FREQ }; 1716 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) { 1717 mhz = 1; // looks like an error but can be divided by 1718 } else { 1719 mhz /= 1000000; // reported in millions 1720 } 1721 1722 char model[100]; 1723 size = sizeof(model); 1724 int mib_model[] = { CTL_HW, HW_MODEL }; 1725 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) { 1726 strncpy(model, cpu_arch, sizeof(model)); 1727 } 1728 1729 char machine[100]; 1730 size = sizeof(machine); 1731 int mib_machine[] = { CTL_HW, HW_MACHINE }; 1732 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) { 1733 strncpy(machine, "", sizeof(machine)); 1734 } 1735 1736 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz); 1737 } 1738 1739 void os::print_memory_info(outputStream* st) { 1740 1741 st->print("Memory:"); 1742 st->print(" %dk page", os::vm_page_size()>>10); 1743 1744 st->print(", physical " UINT64_FORMAT "k", 1745 os::physical_memory() >> 10); 1746 st->print("(" UINT64_FORMAT "k free)", 1747 os::available_memory() >> 10); 1748 st->cr(); 1749 } 1750 1751 void os::print_siginfo(outputStream* st, void* siginfo) { 1752 const siginfo_t* si = (const siginfo_t*)siginfo; 1753 1754 os::Posix::print_siginfo_brief(st, si); 1755 1756 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1757 UseSharedSpaces) { 1758 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1759 if (mapinfo->is_in_shared_space(si->si_addr)) { 1760 st->print("\n\nError accessing class data sharing archive." \ 1761 " Mapped file inaccessible during execution, " \ 1762 " possible disk/network problem."); 1763 } 1764 } 1765 st->cr(); 1766 } 1767 1768 1769 static void print_signal_handler(outputStream* st, int sig, 1770 char* buf, size_t buflen); 1771 1772 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1773 st->print_cr("Signal Handlers:"); 1774 print_signal_handler(st, SIGSEGV, buf, buflen); 1775 print_signal_handler(st, SIGBUS , buf, buflen); 1776 print_signal_handler(st, SIGFPE , buf, buflen); 1777 print_signal_handler(st, SIGPIPE, buf, buflen); 1778 print_signal_handler(st, SIGXFSZ, buf, buflen); 1779 print_signal_handler(st, SIGILL , buf, buflen); 1780 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1781 print_signal_handler(st, SR_signum, buf, buflen); 1782 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1783 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1784 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1785 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1786 } 1787 1788 static char saved_jvm_path[MAXPATHLEN] = {0}; 1789 1790 // Find the full path to the current module, libjvm 1791 void os::jvm_path(char *buf, jint buflen) { 1792 // Error checking. 1793 if (buflen < MAXPATHLEN) { 1794 assert(false, "must use a large-enough buffer"); 1795 buf[0] = '\0'; 1796 return; 1797 } 1798 // Lazy resolve the path to current module. 1799 if (saved_jvm_path[0] != 0) { 1800 strcpy(buf, saved_jvm_path); 1801 return; 1802 } 1803 1804 char dli_fname[MAXPATHLEN]; 1805 bool ret = dll_address_to_library_name( 1806 CAST_FROM_FN_PTR(address, os::jvm_path), 1807 dli_fname, sizeof(dli_fname), NULL); 1808 assert(ret, "cannot locate libjvm"); 1809 char *rp = NULL; 1810 if (ret && dli_fname[0] != '\0') { 1811 rp = realpath(dli_fname, buf); 1812 } 1813 if (rp == NULL) { 1814 return; 1815 } 1816 1817 if (Arguments::sun_java_launcher_is_altjvm()) { 1818 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1819 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1820 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1821 // appears at the right place in the string, then assume we are 1822 // installed in a JDK and we're done. Otherwise, check for a 1823 // JAVA_HOME environment variable and construct a path to the JVM 1824 // being overridden. 1825 1826 const char *p = buf + strlen(buf) - 1; 1827 for (int count = 0; p > buf && count < 5; ++count) { 1828 for (--p; p > buf && *p != '/'; --p) 1829 /* empty */ ; 1830 } 1831 1832 if (strncmp(p, "/jre/lib/", 9) != 0) { 1833 // Look for JAVA_HOME in the environment. 1834 char* java_home_var = ::getenv("JAVA_HOME"); 1835 if (java_home_var != NULL && java_home_var[0] != 0) { 1836 char* jrelib_p; 1837 int len; 1838 1839 // Check the current module name "libjvm" 1840 p = strrchr(buf, '/'); 1841 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1842 1843 rp = realpath(java_home_var, buf); 1844 if (rp == NULL) { 1845 return; 1846 } 1847 1848 // determine if this is a legacy image or modules image 1849 // modules image doesn't have "jre" subdirectory 1850 len = strlen(buf); 1851 assert(len < buflen, "Ran out of buffer space"); 1852 jrelib_p = buf + len; 1853 1854 // Add the appropriate library subdir 1855 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1856 if (0 != access(buf, F_OK)) { 1857 snprintf(jrelib_p, buflen-len, "/lib"); 1858 } 1859 1860 // Add the appropriate client or server subdir 1861 len = strlen(buf); 1862 jrelib_p = buf + len; 1863 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1864 if (0 != access(buf, F_OK)) { 1865 snprintf(jrelib_p, buflen-len, "%s", ""); 1866 } 1867 1868 // If the path exists within JAVA_HOME, add the JVM library name 1869 // to complete the path to JVM being overridden. Otherwise fallback 1870 // to the path to the current library. 1871 if (0 == access(buf, F_OK)) { 1872 // Use current module name "libjvm" 1873 len = strlen(buf); 1874 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1875 } else { 1876 // Fall back to path of current library 1877 rp = realpath(dli_fname, buf); 1878 if (rp == NULL) { 1879 return; 1880 } 1881 } 1882 } 1883 } 1884 } 1885 1886 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1887 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1888 } 1889 1890 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1891 // no prefix required, not even "_" 1892 } 1893 1894 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1895 // no suffix required 1896 } 1897 1898 //////////////////////////////////////////////////////////////////////////////// 1899 // sun.misc.Signal support 1900 1901 static volatile jint sigint_count = 0; 1902 1903 static void UserHandler(int sig, void *siginfo, void *context) { 1904 // 4511530 - sem_post is serialized and handled by the manager thread. When 1905 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1906 // don't want to flood the manager thread with sem_post requests. 1907 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1908 return; 1909 } 1910 1911 // Ctrl-C is pressed during error reporting, likely because the error 1912 // handler fails to abort. Let VM die immediately. 1913 if (sig == SIGINT && is_error_reported()) { 1914 os::die(); 1915 } 1916 1917 os::signal_notify(sig); 1918 } 1919 1920 void* os::user_handler() { 1921 return CAST_FROM_FN_PTR(void*, UserHandler); 1922 } 1923 1924 extern "C" { 1925 typedef void (*sa_handler_t)(int); 1926 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1927 } 1928 1929 void* os::signal(int signal_number, void* handler) { 1930 struct sigaction sigAct, oldSigAct; 1931 1932 sigfillset(&(sigAct.sa_mask)); 1933 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1934 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1935 1936 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1937 // -1 means registration failed 1938 return (void *)-1; 1939 } 1940 1941 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1942 } 1943 1944 void os::signal_raise(int signal_number) { 1945 ::raise(signal_number); 1946 } 1947 1948 // The following code is moved from os.cpp for making this 1949 // code platform specific, which it is by its very nature. 1950 1951 // Will be modified when max signal is changed to be dynamic 1952 int os::sigexitnum_pd() { 1953 return NSIG; 1954 } 1955 1956 // a counter for each possible signal value 1957 static volatile jint pending_signals[NSIG+1] = { 0 }; 1958 1959 // Bsd(POSIX) specific hand shaking semaphore. 1960 #ifdef __APPLE__ 1961 typedef semaphore_t os_semaphore_t; 1962 1963 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1964 #define SEM_WAIT(sem) semaphore_wait(sem) 1965 #define SEM_POST(sem) semaphore_signal(sem) 1966 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1967 #else 1968 typedef sem_t os_semaphore_t; 1969 1970 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1971 #define SEM_WAIT(sem) sem_wait(&sem) 1972 #define SEM_POST(sem) sem_post(&sem) 1973 #define SEM_DESTROY(sem) sem_destroy(&sem) 1974 #endif 1975 1976 #ifdef __APPLE__ 1977 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used. 1978 1979 static const char* sem_init_strerror(kern_return_t value) { 1980 switch (value) { 1981 case KERN_INVALID_ARGUMENT: return "Invalid argument"; 1982 case KERN_RESOURCE_SHORTAGE: return "Resource shortage"; 1983 default: return "Unknown"; 1984 } 1985 } 1986 1987 OSXSemaphore::OSXSemaphore(uint value) { 1988 kern_return_t ret = SEM_INIT(_semaphore, value); 1989 1990 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret)); 1991 } 1992 1993 OSXSemaphore::~OSXSemaphore() { 1994 SEM_DESTROY(_semaphore); 1995 } 1996 1997 void OSXSemaphore::signal(uint count) { 1998 for (uint i = 0; i < count; i++) { 1999 kern_return_t ret = SEM_POST(_semaphore); 2000 2001 assert(ret == KERN_SUCCESS, "Failed to signal semaphore"); 2002 } 2003 } 2004 2005 void OSXSemaphore::wait() { 2006 kern_return_t ret; 2007 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) { 2008 // Semaphore was interrupted. Retry. 2009 } 2010 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore"); 2011 } 2012 2013 jlong OSXSemaphore::currenttime() { 2014 struct timeval tv; 2015 gettimeofday(&tv, NULL); 2016 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 2017 } 2018 2019 bool OSXSemaphore::trywait() { 2020 return timedwait(0, 0); 2021 } 2022 2023 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) { 2024 kern_return_t kr = KERN_ABORTED; 2025 mach_timespec_t waitspec; 2026 waitspec.tv_sec = sec; 2027 waitspec.tv_nsec = nsec; 2028 2029 jlong starttime = currenttime(); 2030 2031 kr = semaphore_timedwait(_semaphore, waitspec); 2032 while (kr == KERN_ABORTED) { 2033 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 2034 2035 jlong current = currenttime(); 2036 jlong passedtime = current - starttime; 2037 2038 if (passedtime >= totalwait) { 2039 waitspec.tv_sec = 0; 2040 waitspec.tv_nsec = 0; 2041 } else { 2042 jlong waittime = totalwait - (current - starttime); 2043 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2044 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2045 } 2046 2047 kr = semaphore_timedwait(_semaphore, waitspec); 2048 } 2049 2050 return kr == KERN_SUCCESS; 2051 } 2052 2053 #else 2054 // Use POSIX implementation of semaphores. 2055 2056 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) { 2057 struct timespec ts; 2058 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2059 2060 return ts; 2061 } 2062 2063 #endif // __APPLE__ 2064 2065 static os_semaphore_t sig_sem; 2066 2067 #ifdef __APPLE__ 2068 static OSXSemaphore sr_semaphore; 2069 #else 2070 static PosixSemaphore sr_semaphore; 2071 #endif 2072 2073 void os::signal_init_pd() { 2074 // Initialize signal structures 2075 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2076 2077 // Initialize signal semaphore 2078 ::SEM_INIT(sig_sem, 0); 2079 } 2080 2081 void os::signal_notify(int sig) { 2082 Atomic::inc(&pending_signals[sig]); 2083 ::SEM_POST(sig_sem); 2084 } 2085 2086 static int check_pending_signals(bool wait) { 2087 Atomic::store(0, &sigint_count); 2088 for (;;) { 2089 for (int i = 0; i < NSIG + 1; i++) { 2090 jint n = pending_signals[i]; 2091 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2092 return i; 2093 } 2094 } 2095 if (!wait) { 2096 return -1; 2097 } 2098 JavaThread *thread = JavaThread::current(); 2099 ThreadBlockInVM tbivm(thread); 2100 2101 bool threadIsSuspended; 2102 do { 2103 thread->set_suspend_equivalent(); 2104 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2105 ::SEM_WAIT(sig_sem); 2106 2107 // were we externally suspended while we were waiting? 2108 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2109 if (threadIsSuspended) { 2110 // The semaphore has been incremented, but while we were waiting 2111 // another thread suspended us. We don't want to continue running 2112 // while suspended because that would surprise the thread that 2113 // suspended us. 2114 ::SEM_POST(sig_sem); 2115 2116 thread->java_suspend_self(); 2117 } 2118 } while (threadIsSuspended); 2119 } 2120 } 2121 2122 int os::signal_lookup() { 2123 return check_pending_signals(false); 2124 } 2125 2126 int os::signal_wait() { 2127 return check_pending_signals(true); 2128 } 2129 2130 //////////////////////////////////////////////////////////////////////////////// 2131 // Virtual Memory 2132 2133 int os::vm_page_size() { 2134 // Seems redundant as all get out 2135 assert(os::Bsd::page_size() != -1, "must call os::init"); 2136 return os::Bsd::page_size(); 2137 } 2138 2139 // Solaris allocates memory by pages. 2140 int os::vm_allocation_granularity() { 2141 assert(os::Bsd::page_size() != -1, "must call os::init"); 2142 return os::Bsd::page_size(); 2143 } 2144 2145 // Rationale behind this function: 2146 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2147 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2148 // samples for JITted code. Here we create private executable mapping over the code cache 2149 // and then we can use standard (well, almost, as mapping can change) way to provide 2150 // info for the reporting script by storing timestamp and location of symbol 2151 void bsd_wrap_code(char* base, size_t size) { 2152 static volatile jint cnt = 0; 2153 2154 if (!UseOprofile) { 2155 return; 2156 } 2157 2158 char buf[PATH_MAX + 1]; 2159 int num = Atomic::add(1, &cnt); 2160 2161 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2162 os::get_temp_directory(), os::current_process_id(), num); 2163 unlink(buf); 2164 2165 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2166 2167 if (fd != -1) { 2168 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2169 if (rv != (off_t)-1) { 2170 if (::write(fd, "", 1) == 1) { 2171 mmap(base, size, 2172 PROT_READ|PROT_WRITE|PROT_EXEC, 2173 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2174 } 2175 } 2176 ::close(fd); 2177 unlink(buf); 2178 } 2179 } 2180 2181 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2182 int err) { 2183 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2184 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2185 strerror(err), err); 2186 } 2187 2188 // NOTE: Bsd kernel does not really reserve the pages for us. 2189 // All it does is to check if there are enough free pages 2190 // left at the time of mmap(). This could be a potential 2191 // problem. 2192 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2193 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2194 #ifdef __OpenBSD__ 2195 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2196 if (::mprotect(addr, size, prot) == 0) { 2197 return true; 2198 } 2199 #else 2200 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2201 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2202 if (res != (uintptr_t) MAP_FAILED) { 2203 return true; 2204 } 2205 #endif 2206 2207 // Warn about any commit errors we see in non-product builds just 2208 // in case mmap() doesn't work as described on the man page. 2209 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2210 2211 return false; 2212 } 2213 2214 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2215 bool exec) { 2216 // alignment_hint is ignored on this OS 2217 return pd_commit_memory(addr, size, exec); 2218 } 2219 2220 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2221 const char* mesg) { 2222 assert(mesg != NULL, "mesg must be specified"); 2223 if (!pd_commit_memory(addr, size, exec)) { 2224 // add extra info in product mode for vm_exit_out_of_memory(): 2225 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2226 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg); 2227 } 2228 } 2229 2230 void os::pd_commit_memory_or_exit(char* addr, size_t size, 2231 size_t alignment_hint, bool exec, 2232 const char* mesg) { 2233 // alignment_hint is ignored on this OS 2234 pd_commit_memory_or_exit(addr, size, exec, mesg); 2235 } 2236 2237 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2238 } 2239 2240 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2241 ::madvise(addr, bytes, MADV_DONTNEED); 2242 } 2243 2244 void os::numa_make_global(char *addr, size_t bytes) { 2245 } 2246 2247 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2248 } 2249 2250 bool os::numa_topology_changed() { return false; } 2251 2252 size_t os::numa_get_groups_num() { 2253 return 1; 2254 } 2255 2256 int os::numa_get_group_id() { 2257 return 0; 2258 } 2259 2260 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2261 if (size > 0) { 2262 ids[0] = 0; 2263 return 1; 2264 } 2265 return 0; 2266 } 2267 2268 bool os::get_page_info(char *start, page_info* info) { 2269 return false; 2270 } 2271 2272 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2273 return end; 2274 } 2275 2276 2277 bool os::pd_uncommit_memory(char* addr, size_t size) { 2278 #ifdef __OpenBSD__ 2279 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2280 return ::mprotect(addr, size, PROT_NONE) == 0; 2281 #else 2282 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2283 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2284 return res != (uintptr_t) MAP_FAILED; 2285 #endif 2286 } 2287 2288 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2289 return os::commit_memory(addr, size, !ExecMem); 2290 } 2291 2292 // If this is a growable mapping, remove the guard pages entirely by 2293 // munmap()ping them. If not, just call uncommit_memory(). 2294 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2295 return os::uncommit_memory(addr, size); 2296 } 2297 2298 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2299 // at 'requested_addr'. If there are existing memory mappings at the same 2300 // location, however, they will be overwritten. If 'fixed' is false, 2301 // 'requested_addr' is only treated as a hint, the return value may or 2302 // may not start from the requested address. Unlike Bsd mmap(), this 2303 // function returns NULL to indicate failure. 2304 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2305 char * addr; 2306 int flags; 2307 2308 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2309 if (fixed) { 2310 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2311 flags |= MAP_FIXED; 2312 } 2313 2314 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2315 // touch an uncommitted page. Otherwise, the read/write might 2316 // succeed if we have enough swap space to back the physical page. 2317 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2318 flags, -1, 0); 2319 2320 return addr == MAP_FAILED ? NULL : addr; 2321 } 2322 2323 static int anon_munmap(char * addr, size_t size) { 2324 return ::munmap(addr, size) == 0; 2325 } 2326 2327 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2328 size_t alignment_hint) { 2329 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2330 } 2331 2332 bool os::pd_release_memory(char* addr, size_t size) { 2333 return anon_munmap(addr, size); 2334 } 2335 2336 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2337 // Bsd wants the mprotect address argument to be page aligned. 2338 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2339 2340 // According to SUSv3, mprotect() should only be used with mappings 2341 // established by mmap(), and mmap() always maps whole pages. Unaligned 2342 // 'addr' likely indicates problem in the VM (e.g. trying to change 2343 // protection of malloc'ed or statically allocated memory). Check the 2344 // caller if you hit this assert. 2345 assert(addr == bottom, "sanity check"); 2346 2347 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2348 return ::mprotect(bottom, size, prot) == 0; 2349 } 2350 2351 // Set protections specified 2352 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2353 bool is_committed) { 2354 unsigned int p = 0; 2355 switch (prot) { 2356 case MEM_PROT_NONE: p = PROT_NONE; break; 2357 case MEM_PROT_READ: p = PROT_READ; break; 2358 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2359 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2360 default: 2361 ShouldNotReachHere(); 2362 } 2363 // is_committed is unused. 2364 return bsd_mprotect(addr, bytes, p); 2365 } 2366 2367 bool os::guard_memory(char* addr, size_t size) { 2368 return bsd_mprotect(addr, size, PROT_NONE); 2369 } 2370 2371 bool os::unguard_memory(char* addr, size_t size) { 2372 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2373 } 2374 2375 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2376 return false; 2377 } 2378 2379 // Large page support 2380 2381 static size_t _large_page_size = 0; 2382 2383 void os::large_page_init() { 2384 } 2385 2386 2387 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2388 fatal("This code is not used or maintained."); 2389 2390 // "exec" is passed in but not used. Creating the shared image for 2391 // the code cache doesn't have an SHM_X executable permission to check. 2392 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2393 2394 key_t key = IPC_PRIVATE; 2395 char *addr; 2396 2397 bool warn_on_failure = UseLargePages && 2398 (!FLAG_IS_DEFAULT(UseLargePages) || 2399 !FLAG_IS_DEFAULT(LargePageSizeInBytes)); 2400 2401 // Create a large shared memory region to attach to based on size. 2402 // Currently, size is the total size of the heap 2403 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2404 if (shmid == -1) { 2405 // Possible reasons for shmget failure: 2406 // 1. shmmax is too small for Java heap. 2407 // > check shmmax value: cat /proc/sys/kernel/shmmax 2408 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2409 // 2. not enough large page memory. 2410 // > check available large pages: cat /proc/meminfo 2411 // > increase amount of large pages: 2412 // echo new_value > /proc/sys/vm/nr_hugepages 2413 // Note 1: different Bsd may use different name for this property, 2414 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2415 // Note 2: it's possible there's enough physical memory available but 2416 // they are so fragmented after a long run that they can't 2417 // coalesce into large pages. Try to reserve large pages when 2418 // the system is still "fresh". 2419 if (warn_on_failure) { 2420 warning("Failed to reserve shared memory (errno = %d).", errno); 2421 } 2422 return NULL; 2423 } 2424 2425 // attach to the region 2426 addr = (char*)shmat(shmid, req_addr, 0); 2427 int err = errno; 2428 2429 // Remove shmid. If shmat() is successful, the actual shared memory segment 2430 // will be deleted when it's detached by shmdt() or when the process 2431 // terminates. If shmat() is not successful this will remove the shared 2432 // segment immediately. 2433 shmctl(shmid, IPC_RMID, NULL); 2434 2435 if ((intptr_t)addr == -1) { 2436 if (warn_on_failure) { 2437 warning("Failed to attach shared memory (errno = %d).", err); 2438 } 2439 return NULL; 2440 } 2441 2442 // The memory is committed 2443 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2444 2445 return addr; 2446 } 2447 2448 bool os::release_memory_special(char* base, size_t bytes) { 2449 if (MemTracker::tracking_level() > NMT_minimal) { 2450 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2451 // detaching the SHM segment will also delete it, see reserve_memory_special() 2452 int rslt = shmdt(base); 2453 if (rslt == 0) { 2454 tkr.record((address)base, bytes); 2455 return true; 2456 } else { 2457 return false; 2458 } 2459 } else { 2460 return shmdt(base) == 0; 2461 } 2462 } 2463 2464 size_t os::large_page_size() { 2465 return _large_page_size; 2466 } 2467 2468 // HugeTLBFS allows application to commit large page memory on demand; 2469 // with SysV SHM the entire memory region must be allocated as shared 2470 // memory. 2471 bool os::can_commit_large_page_memory() { 2472 return UseHugeTLBFS; 2473 } 2474 2475 bool os::can_execute_large_page_memory() { 2476 return UseHugeTLBFS; 2477 } 2478 2479 // Reserve memory at an arbitrary address, only if that area is 2480 // available (and not reserved for something else). 2481 2482 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2483 const int max_tries = 10; 2484 char* base[max_tries]; 2485 size_t size[max_tries]; 2486 const size_t gap = 0x000000; 2487 2488 // Assert only that the size is a multiple of the page size, since 2489 // that's all that mmap requires, and since that's all we really know 2490 // about at this low abstraction level. If we need higher alignment, 2491 // we can either pass an alignment to this method or verify alignment 2492 // in one of the methods further up the call chain. See bug 5044738. 2493 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2494 2495 // Repeatedly allocate blocks until the block is allocated at the 2496 // right spot. 2497 2498 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2499 // if kernel honors the hint then we can return immediately. 2500 char * addr = anon_mmap(requested_addr, bytes, false); 2501 if (addr == requested_addr) { 2502 return requested_addr; 2503 } 2504 2505 if (addr != NULL) { 2506 // mmap() is successful but it fails to reserve at the requested address 2507 anon_munmap(addr, bytes); 2508 } 2509 2510 int i; 2511 for (i = 0; i < max_tries; ++i) { 2512 base[i] = reserve_memory(bytes); 2513 2514 if (base[i] != NULL) { 2515 // Is this the block we wanted? 2516 if (base[i] == requested_addr) { 2517 size[i] = bytes; 2518 break; 2519 } 2520 2521 // Does this overlap the block we wanted? Give back the overlapped 2522 // parts and try again. 2523 2524 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2525 if (top_overlap >= 0 && top_overlap < bytes) { 2526 unmap_memory(base[i], top_overlap); 2527 base[i] += top_overlap; 2528 size[i] = bytes - top_overlap; 2529 } else { 2530 size_t bottom_overlap = base[i] + bytes - requested_addr; 2531 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2532 unmap_memory(requested_addr, bottom_overlap); 2533 size[i] = bytes - bottom_overlap; 2534 } else { 2535 size[i] = bytes; 2536 } 2537 } 2538 } 2539 } 2540 2541 // Give back the unused reserved pieces. 2542 2543 for (int j = 0; j < i; ++j) { 2544 if (base[j] != NULL) { 2545 unmap_memory(base[j], size[j]); 2546 } 2547 } 2548 2549 if (i < max_tries) { 2550 return requested_addr; 2551 } else { 2552 return NULL; 2553 } 2554 } 2555 2556 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2557 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2558 } 2559 2560 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2561 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2562 } 2563 2564 void os::naked_short_sleep(jlong ms) { 2565 struct timespec req; 2566 2567 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2568 req.tv_sec = 0; 2569 if (ms > 0) { 2570 req.tv_nsec = (ms % 1000) * 1000000; 2571 } else { 2572 req.tv_nsec = 1; 2573 } 2574 2575 nanosleep(&req, NULL); 2576 2577 return; 2578 } 2579 2580 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2581 void os::infinite_sleep() { 2582 while (true) { // sleep forever ... 2583 ::sleep(100); // ... 100 seconds at a time 2584 } 2585 } 2586 2587 // Used to convert frequent JVM_Yield() to nops 2588 bool os::dont_yield() { 2589 return DontYieldALot; 2590 } 2591 2592 void os::naked_yield() { 2593 sched_yield(); 2594 } 2595 2596 //////////////////////////////////////////////////////////////////////////////// 2597 // thread priority support 2598 2599 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2600 // only supports dynamic priority, static priority must be zero. For real-time 2601 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2602 // However, for large multi-threaded applications, SCHED_RR is not only slower 2603 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2604 // of 5 runs - Sep 2005). 2605 // 2606 // The following code actually changes the niceness of kernel-thread/LWP. It 2607 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2608 // not the entire user process, and user level threads are 1:1 mapped to kernel 2609 // threads. It has always been the case, but could change in the future. For 2610 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2611 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2612 2613 #if !defined(__APPLE__) 2614 int os::java_to_os_priority[CriticalPriority + 1] = { 2615 19, // 0 Entry should never be used 2616 2617 0, // 1 MinPriority 2618 3, // 2 2619 6, // 3 2620 2621 10, // 4 2622 15, // 5 NormPriority 2623 18, // 6 2624 2625 21, // 7 2626 25, // 8 2627 28, // 9 NearMaxPriority 2628 2629 31, // 10 MaxPriority 2630 2631 31 // 11 CriticalPriority 2632 }; 2633 #else 2634 // Using Mach high-level priority assignments 2635 int os::java_to_os_priority[CriticalPriority + 1] = { 2636 0, // 0 Entry should never be used (MINPRI_USER) 2637 2638 27, // 1 MinPriority 2639 28, // 2 2640 29, // 3 2641 2642 30, // 4 2643 31, // 5 NormPriority (BASEPRI_DEFAULT) 2644 32, // 6 2645 2646 33, // 7 2647 34, // 8 2648 35, // 9 NearMaxPriority 2649 2650 36, // 10 MaxPriority 2651 2652 36 // 11 CriticalPriority 2653 }; 2654 #endif 2655 2656 static int prio_init() { 2657 if (ThreadPriorityPolicy == 1) { 2658 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2659 // if effective uid is not root. Perhaps, a more elegant way of doing 2660 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2661 if (geteuid() != 0) { 2662 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2663 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2664 } 2665 ThreadPriorityPolicy = 0; 2666 } 2667 } 2668 if (UseCriticalJavaThreadPriority) { 2669 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2670 } 2671 return 0; 2672 } 2673 2674 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2675 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2676 2677 #ifdef __OpenBSD__ 2678 // OpenBSD pthread_setprio starves low priority threads 2679 return OS_OK; 2680 #elif defined(__FreeBSD__) 2681 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2682 #elif defined(__APPLE__) || defined(__NetBSD__) 2683 struct sched_param sp; 2684 int policy; 2685 pthread_t self = pthread_self(); 2686 2687 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2688 return OS_ERR; 2689 } 2690 2691 sp.sched_priority = newpri; 2692 if (pthread_setschedparam(self, policy, &sp) != 0) { 2693 return OS_ERR; 2694 } 2695 2696 return OS_OK; 2697 #else 2698 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2699 return (ret == 0) ? OS_OK : OS_ERR; 2700 #endif 2701 } 2702 2703 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2704 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2705 *priority_ptr = java_to_os_priority[NormPriority]; 2706 return OS_OK; 2707 } 2708 2709 errno = 0; 2710 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2711 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2712 #elif defined(__APPLE__) || defined(__NetBSD__) 2713 int policy; 2714 struct sched_param sp; 2715 2716 pthread_getschedparam(pthread_self(), &policy, &sp); 2717 *priority_ptr = sp.sched_priority; 2718 #else 2719 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2720 #endif 2721 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2722 } 2723 2724 // Hint to the underlying OS that a task switch would not be good. 2725 // Void return because it's a hint and can fail. 2726 void os::hint_no_preempt() {} 2727 2728 //////////////////////////////////////////////////////////////////////////////// 2729 // suspend/resume support 2730 2731 // the low-level signal-based suspend/resume support is a remnant from the 2732 // old VM-suspension that used to be for java-suspension, safepoints etc, 2733 // within hotspot. Now there is a single use-case for this: 2734 // - calling get_thread_pc() on the VMThread by the flat-profiler task 2735 // that runs in the watcher thread. 2736 // The remaining code is greatly simplified from the more general suspension 2737 // code that used to be used. 2738 // 2739 // The protocol is quite simple: 2740 // - suspend: 2741 // - sends a signal to the target thread 2742 // - polls the suspend state of the osthread using a yield loop 2743 // - target thread signal handler (SR_handler) sets suspend state 2744 // and blocks in sigsuspend until continued 2745 // - resume: 2746 // - sets target osthread state to continue 2747 // - sends signal to end the sigsuspend loop in the SR_handler 2748 // 2749 // Note that the SR_lock plays no role in this suspend/resume protocol. 2750 2751 static void resume_clear_context(OSThread *osthread) { 2752 osthread->set_ucontext(NULL); 2753 osthread->set_siginfo(NULL); 2754 } 2755 2756 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2757 osthread->set_ucontext(context); 2758 osthread->set_siginfo(siginfo); 2759 } 2760 2761 // Handler function invoked when a thread's execution is suspended or 2762 // resumed. We have to be careful that only async-safe functions are 2763 // called here (Note: most pthread functions are not async safe and 2764 // should be avoided.) 2765 // 2766 // Note: sigwait() is a more natural fit than sigsuspend() from an 2767 // interface point of view, but sigwait() prevents the signal hander 2768 // from being run. libpthread would get very confused by not having 2769 // its signal handlers run and prevents sigwait()'s use with the 2770 // mutex granting granting signal. 2771 // 2772 // Currently only ever called on the VMThread or JavaThread 2773 // 2774 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2775 // Save and restore errno to avoid confusing native code with EINTR 2776 // after sigsuspend. 2777 int old_errno = errno; 2778 2779 Thread* thread = Thread::current(); 2780 OSThread* osthread = thread->osthread(); 2781 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2782 2783 os::SuspendResume::State current = osthread->sr.state(); 2784 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2785 suspend_save_context(osthread, siginfo, context); 2786 2787 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2788 os::SuspendResume::State state = osthread->sr.suspended(); 2789 if (state == os::SuspendResume::SR_SUSPENDED) { 2790 sigset_t suspend_set; // signals for sigsuspend() 2791 2792 // get current set of blocked signals and unblock resume signal 2793 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2794 sigdelset(&suspend_set, SR_signum); 2795 2796 sr_semaphore.signal(); 2797 // wait here until we are resumed 2798 while (1) { 2799 sigsuspend(&suspend_set); 2800 2801 os::SuspendResume::State result = osthread->sr.running(); 2802 if (result == os::SuspendResume::SR_RUNNING) { 2803 sr_semaphore.signal(); 2804 break; 2805 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2806 ShouldNotReachHere(); 2807 } 2808 } 2809 2810 } else if (state == os::SuspendResume::SR_RUNNING) { 2811 // request was cancelled, continue 2812 } else { 2813 ShouldNotReachHere(); 2814 } 2815 2816 resume_clear_context(osthread); 2817 } else if (current == os::SuspendResume::SR_RUNNING) { 2818 // request was cancelled, continue 2819 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2820 // ignore 2821 } else { 2822 // ignore 2823 } 2824 2825 errno = old_errno; 2826 } 2827 2828 2829 static int SR_initialize() { 2830 struct sigaction act; 2831 char *s; 2832 // Get signal number to use for suspend/resume 2833 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2834 int sig = ::strtol(s, 0, 10); 2835 if (sig > 0 || sig < NSIG) { 2836 SR_signum = sig; 2837 } 2838 } 2839 2840 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2841 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2842 2843 sigemptyset(&SR_sigset); 2844 sigaddset(&SR_sigset, SR_signum); 2845 2846 // Set up signal handler for suspend/resume 2847 act.sa_flags = SA_RESTART|SA_SIGINFO; 2848 act.sa_handler = (void (*)(int)) SR_handler; 2849 2850 // SR_signum is blocked by default. 2851 // 4528190 - We also need to block pthread restart signal (32 on all 2852 // supported Bsd platforms). Note that BsdThreads need to block 2853 // this signal for all threads to work properly. So we don't have 2854 // to use hard-coded signal number when setting up the mask. 2855 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2856 2857 if (sigaction(SR_signum, &act, 0) == -1) { 2858 return -1; 2859 } 2860 2861 // Save signal flag 2862 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2863 return 0; 2864 } 2865 2866 static int sr_notify(OSThread* osthread) { 2867 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2868 assert_status(status == 0, status, "pthread_kill"); 2869 return status; 2870 } 2871 2872 // "Randomly" selected value for how long we want to spin 2873 // before bailing out on suspending a thread, also how often 2874 // we send a signal to a thread we want to resume 2875 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2876 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2877 2878 // returns true on success and false on error - really an error is fatal 2879 // but this seems the normal response to library errors 2880 static bool do_suspend(OSThread* osthread) { 2881 assert(osthread->sr.is_running(), "thread should be running"); 2882 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2883 2884 // mark as suspended and send signal 2885 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2886 // failed to switch, state wasn't running? 2887 ShouldNotReachHere(); 2888 return false; 2889 } 2890 2891 if (sr_notify(osthread) != 0) { 2892 ShouldNotReachHere(); 2893 } 2894 2895 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2896 while (true) { 2897 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2898 break; 2899 } else { 2900 // timeout 2901 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2902 if (cancelled == os::SuspendResume::SR_RUNNING) { 2903 return false; 2904 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2905 // make sure that we consume the signal on the semaphore as well 2906 sr_semaphore.wait(); 2907 break; 2908 } else { 2909 ShouldNotReachHere(); 2910 return false; 2911 } 2912 } 2913 } 2914 2915 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2916 return true; 2917 } 2918 2919 static void do_resume(OSThread* osthread) { 2920 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2921 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2922 2923 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2924 // failed to switch to WAKEUP_REQUEST 2925 ShouldNotReachHere(); 2926 return; 2927 } 2928 2929 while (true) { 2930 if (sr_notify(osthread) == 0) { 2931 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2932 if (osthread->sr.is_running()) { 2933 return; 2934 } 2935 } 2936 } else { 2937 ShouldNotReachHere(); 2938 } 2939 } 2940 2941 guarantee(osthread->sr.is_running(), "Must be running!"); 2942 } 2943 2944 /////////////////////////////////////////////////////////////////////////////////// 2945 // signal handling (except suspend/resume) 2946 2947 // This routine may be used by user applications as a "hook" to catch signals. 2948 // The user-defined signal handler must pass unrecognized signals to this 2949 // routine, and if it returns true (non-zero), then the signal handler must 2950 // return immediately. If the flag "abort_if_unrecognized" is true, then this 2951 // routine will never retun false (zero), but instead will execute a VM panic 2952 // routine kill the process. 2953 // 2954 // If this routine returns false, it is OK to call it again. This allows 2955 // the user-defined signal handler to perform checks either before or after 2956 // the VM performs its own checks. Naturally, the user code would be making 2957 // a serious error if it tried to handle an exception (such as a null check 2958 // or breakpoint) that the VM was generating for its own correct operation. 2959 // 2960 // This routine may recognize any of the following kinds of signals: 2961 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2962 // It should be consulted by handlers for any of those signals. 2963 // 2964 // The caller of this routine must pass in the three arguments supplied 2965 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 2966 // field of the structure passed to sigaction(). This routine assumes that 2967 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2968 // 2969 // Note that the VM will print warnings if it detects conflicting signal 2970 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2971 // 2972 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2973 void* ucontext, 2974 int abort_if_unrecognized); 2975 2976 void signalHandler(int sig, siginfo_t* info, void* uc) { 2977 assert(info != NULL && uc != NULL, "it must be old kernel"); 2978 int orig_errno = errno; // Preserve errno value over signal handler. 2979 JVM_handle_bsd_signal(sig, info, uc, true); 2980 errno = orig_errno; 2981 } 2982 2983 2984 // This boolean allows users to forward their own non-matching signals 2985 // to JVM_handle_bsd_signal, harmlessly. 2986 bool os::Bsd::signal_handlers_are_installed = false; 2987 2988 // For signal-chaining 2989 struct sigaction os::Bsd::sigact[MAXSIGNUM]; 2990 unsigned int os::Bsd::sigs = 0; 2991 bool os::Bsd::libjsig_is_loaded = false; 2992 typedef struct sigaction *(*get_signal_t)(int); 2993 get_signal_t os::Bsd::get_signal_action = NULL; 2994 2995 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2996 struct sigaction *actp = NULL; 2997 2998 if (libjsig_is_loaded) { 2999 // Retrieve the old signal handler from libjsig 3000 actp = (*get_signal_action)(sig); 3001 } 3002 if (actp == NULL) { 3003 // Retrieve the preinstalled signal handler from jvm 3004 actp = get_preinstalled_handler(sig); 3005 } 3006 3007 return actp; 3008 } 3009 3010 static bool call_chained_handler(struct sigaction *actp, int sig, 3011 siginfo_t *siginfo, void *context) { 3012 // Call the old signal handler 3013 if (actp->sa_handler == SIG_DFL) { 3014 // It's more reasonable to let jvm treat it as an unexpected exception 3015 // instead of taking the default action. 3016 return false; 3017 } else if (actp->sa_handler != SIG_IGN) { 3018 if ((actp->sa_flags & SA_NODEFER) == 0) { 3019 // automaticlly block the signal 3020 sigaddset(&(actp->sa_mask), sig); 3021 } 3022 3023 sa_handler_t hand; 3024 sa_sigaction_t sa; 3025 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3026 // retrieve the chained handler 3027 if (siginfo_flag_set) { 3028 sa = actp->sa_sigaction; 3029 } else { 3030 hand = actp->sa_handler; 3031 } 3032 3033 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3034 actp->sa_handler = SIG_DFL; 3035 } 3036 3037 // try to honor the signal mask 3038 sigset_t oset; 3039 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3040 3041 // call into the chained handler 3042 if (siginfo_flag_set) { 3043 (*sa)(sig, siginfo, context); 3044 } else { 3045 (*hand)(sig); 3046 } 3047 3048 // restore the signal mask 3049 pthread_sigmask(SIG_SETMASK, &oset, 0); 3050 } 3051 // Tell jvm's signal handler the signal is taken care of. 3052 return true; 3053 } 3054 3055 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3056 bool chained = false; 3057 // signal-chaining 3058 if (UseSignalChaining) { 3059 struct sigaction *actp = get_chained_signal_action(sig); 3060 if (actp != NULL) { 3061 chained = call_chained_handler(actp, sig, siginfo, context); 3062 } 3063 } 3064 return chained; 3065 } 3066 3067 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3068 if ((((unsigned int)1 << sig) & sigs) != 0) { 3069 return &sigact[sig]; 3070 } 3071 return NULL; 3072 } 3073 3074 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3075 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3076 sigact[sig] = oldAct; 3077 sigs |= (unsigned int)1 << sig; 3078 } 3079 3080 // for diagnostic 3081 int os::Bsd::sigflags[MAXSIGNUM]; 3082 3083 int os::Bsd::get_our_sigflags(int sig) { 3084 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3085 return sigflags[sig]; 3086 } 3087 3088 void os::Bsd::set_our_sigflags(int sig, int flags) { 3089 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3090 sigflags[sig] = flags; 3091 } 3092 3093 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3094 // Check for overwrite. 3095 struct sigaction oldAct; 3096 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3097 3098 void* oldhand = oldAct.sa_sigaction 3099 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3100 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3101 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3102 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3103 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3104 if (AllowUserSignalHandlers || !set_installed) { 3105 // Do not overwrite; user takes responsibility to forward to us. 3106 return; 3107 } else if (UseSignalChaining) { 3108 // save the old handler in jvm 3109 save_preinstalled_handler(sig, oldAct); 3110 // libjsig also interposes the sigaction() call below and saves the 3111 // old sigaction on it own. 3112 } else { 3113 fatal("Encountered unexpected pre-existing sigaction handler " 3114 "%#lx for signal %d.", (long)oldhand, sig); 3115 } 3116 } 3117 3118 struct sigaction sigAct; 3119 sigfillset(&(sigAct.sa_mask)); 3120 sigAct.sa_handler = SIG_DFL; 3121 if (!set_installed) { 3122 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3123 } else { 3124 sigAct.sa_sigaction = signalHandler; 3125 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3126 } 3127 #ifdef __APPLE__ 3128 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3129 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3130 // if the signal handler declares it will handle it on alternate stack. 3131 // Notice we only declare we will handle it on alt stack, but we are not 3132 // actually going to use real alt stack - this is just a workaround. 3133 // Please see ux_exception.c, method catch_mach_exception_raise for details 3134 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3135 if (sig == SIGSEGV) { 3136 sigAct.sa_flags |= SA_ONSTACK; 3137 } 3138 #endif 3139 3140 // Save flags, which are set by ours 3141 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3142 sigflags[sig] = sigAct.sa_flags; 3143 3144 int ret = sigaction(sig, &sigAct, &oldAct); 3145 assert(ret == 0, "check"); 3146 3147 void* oldhand2 = oldAct.sa_sigaction 3148 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3149 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3150 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3151 } 3152 3153 // install signal handlers for signals that HotSpot needs to 3154 // handle in order to support Java-level exception handling. 3155 3156 void os::Bsd::install_signal_handlers() { 3157 if (!signal_handlers_are_installed) { 3158 signal_handlers_are_installed = true; 3159 3160 // signal-chaining 3161 typedef void (*signal_setting_t)(); 3162 signal_setting_t begin_signal_setting = NULL; 3163 signal_setting_t end_signal_setting = NULL; 3164 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3165 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3166 if (begin_signal_setting != NULL) { 3167 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3168 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3169 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3170 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3171 libjsig_is_loaded = true; 3172 assert(UseSignalChaining, "should enable signal-chaining"); 3173 } 3174 if (libjsig_is_loaded) { 3175 // Tell libjsig jvm is setting signal handlers 3176 (*begin_signal_setting)(); 3177 } 3178 3179 set_signal_handler(SIGSEGV, true); 3180 set_signal_handler(SIGPIPE, true); 3181 set_signal_handler(SIGBUS, true); 3182 set_signal_handler(SIGILL, true); 3183 set_signal_handler(SIGFPE, true); 3184 set_signal_handler(SIGXFSZ, true); 3185 3186 #if defined(__APPLE__) 3187 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3188 // signals caught and handled by the JVM. To work around this, we reset the mach task 3189 // signal handler that's placed on our process by CrashReporter. This disables 3190 // CrashReporter-based reporting. 3191 // 3192 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3193 // on caught fatal signals. 3194 // 3195 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3196 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3197 // exception handling, while leaving the standard BSD signal handlers functional. 3198 kern_return_t kr; 3199 kr = task_set_exception_ports(mach_task_self(), 3200 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3201 MACH_PORT_NULL, 3202 EXCEPTION_STATE_IDENTITY, 3203 MACHINE_THREAD_STATE); 3204 3205 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3206 #endif 3207 3208 if (libjsig_is_loaded) { 3209 // Tell libjsig jvm finishes setting signal handlers 3210 (*end_signal_setting)(); 3211 } 3212 3213 // We don't activate signal checker if libjsig is in place, we trust ourselves 3214 // and if UserSignalHandler is installed all bets are off 3215 if (CheckJNICalls) { 3216 if (libjsig_is_loaded) { 3217 if (PrintJNIResolving) { 3218 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3219 } 3220 check_signals = false; 3221 } 3222 if (AllowUserSignalHandlers) { 3223 if (PrintJNIResolving) { 3224 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3225 } 3226 check_signals = false; 3227 } 3228 } 3229 } 3230 } 3231 3232 3233 ///// 3234 // glibc on Bsd platform uses non-documented flag 3235 // to indicate, that some special sort of signal 3236 // trampoline is used. 3237 // We will never set this flag, and we should 3238 // ignore this flag in our diagnostic 3239 #ifdef SIGNIFICANT_SIGNAL_MASK 3240 #undef SIGNIFICANT_SIGNAL_MASK 3241 #endif 3242 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3243 3244 static const char* get_signal_handler_name(address handler, 3245 char* buf, int buflen) { 3246 int offset; 3247 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3248 if (found) { 3249 // skip directory names 3250 const char *p1, *p2; 3251 p1 = buf; 3252 size_t len = strlen(os::file_separator()); 3253 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3254 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3255 } else { 3256 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3257 } 3258 return buf; 3259 } 3260 3261 static void print_signal_handler(outputStream* st, int sig, 3262 char* buf, size_t buflen) { 3263 struct sigaction sa; 3264 3265 sigaction(sig, NULL, &sa); 3266 3267 // See comment for SIGNIFICANT_SIGNAL_MASK define 3268 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3269 3270 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3271 3272 address handler = (sa.sa_flags & SA_SIGINFO) 3273 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3274 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3275 3276 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3277 st->print("SIG_DFL"); 3278 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3279 st->print("SIG_IGN"); 3280 } else { 3281 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3282 } 3283 3284 st->print(", sa_mask[0]="); 3285 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3286 3287 address rh = VMError::get_resetted_sighandler(sig); 3288 // May be, handler was resetted by VMError? 3289 if (rh != NULL) { 3290 handler = rh; 3291 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3292 } 3293 3294 st->print(", sa_flags="); 3295 os::Posix::print_sa_flags(st, sa.sa_flags); 3296 3297 // Check: is it our handler? 3298 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3299 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3300 // It is our signal handler 3301 // check for flags, reset system-used one! 3302 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3303 st->print( 3304 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3305 os::Bsd::get_our_sigflags(sig)); 3306 } 3307 } 3308 st->cr(); 3309 } 3310 3311 3312 #define DO_SIGNAL_CHECK(sig) \ 3313 do { \ 3314 if (!sigismember(&check_signal_done, sig)) { \ 3315 os::Bsd::check_signal_handler(sig); \ 3316 } \ 3317 } while (0) 3318 3319 // This method is a periodic task to check for misbehaving JNI applications 3320 // under CheckJNI, we can add any periodic checks here 3321 3322 void os::run_periodic_checks() { 3323 3324 if (check_signals == false) return; 3325 3326 // SEGV and BUS if overridden could potentially prevent 3327 // generation of hs*.log in the event of a crash, debugging 3328 // such a case can be very challenging, so we absolutely 3329 // check the following for a good measure: 3330 DO_SIGNAL_CHECK(SIGSEGV); 3331 DO_SIGNAL_CHECK(SIGILL); 3332 DO_SIGNAL_CHECK(SIGFPE); 3333 DO_SIGNAL_CHECK(SIGBUS); 3334 DO_SIGNAL_CHECK(SIGPIPE); 3335 DO_SIGNAL_CHECK(SIGXFSZ); 3336 3337 3338 // ReduceSignalUsage allows the user to override these handlers 3339 // see comments at the very top and jvm_solaris.h 3340 if (!ReduceSignalUsage) { 3341 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3342 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3343 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3344 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3345 } 3346 3347 DO_SIGNAL_CHECK(SR_signum); 3348 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3349 } 3350 3351 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3352 3353 static os_sigaction_t os_sigaction = NULL; 3354 3355 void os::Bsd::check_signal_handler(int sig) { 3356 char buf[O_BUFLEN]; 3357 address jvmHandler = NULL; 3358 3359 3360 struct sigaction act; 3361 if (os_sigaction == NULL) { 3362 // only trust the default sigaction, in case it has been interposed 3363 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3364 if (os_sigaction == NULL) return; 3365 } 3366 3367 os_sigaction(sig, (struct sigaction*)NULL, &act); 3368 3369 3370 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3371 3372 address thisHandler = (act.sa_flags & SA_SIGINFO) 3373 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3374 : CAST_FROM_FN_PTR(address, act.sa_handler); 3375 3376 3377 switch (sig) { 3378 case SIGSEGV: 3379 case SIGBUS: 3380 case SIGFPE: 3381 case SIGPIPE: 3382 case SIGILL: 3383 case SIGXFSZ: 3384 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3385 break; 3386 3387 case SHUTDOWN1_SIGNAL: 3388 case SHUTDOWN2_SIGNAL: 3389 case SHUTDOWN3_SIGNAL: 3390 case BREAK_SIGNAL: 3391 jvmHandler = (address)user_handler(); 3392 break; 3393 3394 case INTERRUPT_SIGNAL: 3395 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3396 break; 3397 3398 default: 3399 if (sig == SR_signum) { 3400 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3401 } else { 3402 return; 3403 } 3404 break; 3405 } 3406 3407 if (thisHandler != jvmHandler) { 3408 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3409 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3410 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3411 // No need to check this sig any longer 3412 sigaddset(&check_signal_done, sig); 3413 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3414 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3415 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3416 exception_name(sig, buf, O_BUFLEN)); 3417 } 3418 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3419 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3420 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3421 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3422 // No need to check this sig any longer 3423 sigaddset(&check_signal_done, sig); 3424 } 3425 3426 // Dump all the signal 3427 if (sigismember(&check_signal_done, sig)) { 3428 print_signal_handlers(tty, buf, O_BUFLEN); 3429 } 3430 } 3431 3432 extern void report_error(char* file_name, int line_no, char* title, 3433 char* format, ...); 3434 3435 extern bool signal_name(int signo, char* buf, size_t len); 3436 3437 const char* os::exception_name(int exception_code, char* buf, size_t size) { 3438 if (0 < exception_code && exception_code <= SIGRTMAX) { 3439 // signal 3440 if (!signal_name(exception_code, buf, size)) { 3441 jio_snprintf(buf, size, "SIG%d", exception_code); 3442 } 3443 return buf; 3444 } else { 3445 return NULL; 3446 } 3447 } 3448 3449 // this is called _before_ the most of global arguments have been parsed 3450 void os::init(void) { 3451 char dummy; // used to get a guess on initial stack address 3452 // first_hrtime = gethrtime(); 3453 3454 // With BsdThreads the JavaMain thread pid (primordial thread) 3455 // is different than the pid of the java launcher thread. 3456 // So, on Bsd, the launcher thread pid is passed to the VM 3457 // via the sun.java.launcher.pid property. 3458 // Use this property instead of getpid() if it was correctly passed. 3459 // See bug 6351349. 3460 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3461 3462 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3463 3464 clock_tics_per_sec = CLK_TCK; 3465 3466 init_random(1234567); 3467 3468 ThreadCritical::initialize(); 3469 3470 Bsd::set_page_size(getpagesize()); 3471 if (Bsd::page_size() == -1) { 3472 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", strerror(errno)); 3473 } 3474 init_page_sizes((size_t) Bsd::page_size()); 3475 3476 Bsd::initialize_system_info(); 3477 3478 // main_thread points to the aboriginal thread 3479 Bsd::_main_thread = pthread_self(); 3480 3481 Bsd::clock_init(); 3482 initial_time_count = javaTimeNanos(); 3483 3484 #ifdef __APPLE__ 3485 // XXXDARWIN 3486 // Work around the unaligned VM callbacks in hotspot's 3487 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3488 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3489 // alignment when doing symbol lookup. To work around this, we force early 3490 // binding of all symbols now, thus binding when alignment is known-good. 3491 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3492 #endif 3493 } 3494 3495 // To install functions for atexit system call 3496 extern "C" { 3497 static void perfMemory_exit_helper() { 3498 perfMemory_exit(); 3499 } 3500 } 3501 3502 // this is called _after_ the global arguments have been parsed 3503 jint os::init_2(void) { 3504 // Allocate a single page and mark it as readable for safepoint polling 3505 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3506 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3507 3508 os::set_polling_page(polling_page); 3509 3510 #ifndef PRODUCT 3511 if (Verbose && PrintMiscellaneous) { 3512 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", 3513 (intptr_t)polling_page); 3514 } 3515 #endif 3516 3517 if (!UseMembar) { 3518 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3519 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3520 os::set_memory_serialize_page(mem_serialize_page); 3521 3522 #ifndef PRODUCT 3523 if (Verbose && PrintMiscellaneous) { 3524 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", 3525 (intptr_t)mem_serialize_page); 3526 } 3527 #endif 3528 } 3529 3530 // initialize suspend/resume support - must do this before signal_sets_init() 3531 if (SR_initialize() != 0) { 3532 perror("SR_initialize failed"); 3533 return JNI_ERR; 3534 } 3535 3536 Bsd::signal_sets_init(); 3537 Bsd::install_signal_handlers(); 3538 3539 // Check minimum allowable stack size for thread creation and to initialize 3540 // the java system classes, including StackOverflowError - depends on page 3541 // size. Add a page for compiler2 recursion in main thread. 3542 // Add in 2*BytesPerWord times page size to account for VM stack during 3543 // class initialization depending on 32 or 64 bit VM. 3544 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3545 (size_t)(StackReservedPages+StackYellowPages+StackRedPages+StackShadowPages+ 3546 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3547 3548 size_t threadStackSizeInBytes = ThreadStackSize * K; 3549 if (threadStackSizeInBytes != 0 && 3550 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3551 tty->print_cr("\nThe stack size specified is too small, " 3552 "Specify at least %dk", 3553 os::Bsd::min_stack_allowed/ K); 3554 return JNI_ERR; 3555 } 3556 3557 // Make the stack size a multiple of the page size so that 3558 // the yellow/red zones can be guarded. 3559 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3560 vm_page_size())); 3561 3562 if (MaxFDLimit) { 3563 // set the number of file descriptors to max. print out error 3564 // if getrlimit/setrlimit fails but continue regardless. 3565 struct rlimit nbr_files; 3566 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3567 if (status != 0) { 3568 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3569 perror("os::init_2 getrlimit failed"); 3570 } 3571 } else { 3572 nbr_files.rlim_cur = nbr_files.rlim_max; 3573 3574 #ifdef __APPLE__ 3575 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3576 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3577 // be used instead 3578 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3579 #endif 3580 3581 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3582 if (status != 0) { 3583 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3584 perror("os::init_2 setrlimit failed"); 3585 } 3586 } 3587 } 3588 } 3589 3590 // at-exit methods are called in the reverse order of their registration. 3591 // atexit functions are called on return from main or as a result of a 3592 // call to exit(3C). There can be only 32 of these functions registered 3593 // and atexit() does not set errno. 3594 3595 if (PerfAllowAtExitRegistration) { 3596 // only register atexit functions if PerfAllowAtExitRegistration is set. 3597 // atexit functions can be delayed until process exit time, which 3598 // can be problematic for embedded VM situations. Embedded VMs should 3599 // call DestroyJavaVM() to assure that VM resources are released. 3600 3601 // note: perfMemory_exit_helper atexit function may be removed in 3602 // the future if the appropriate cleanup code can be added to the 3603 // VM_Exit VMOperation's doit method. 3604 if (atexit(perfMemory_exit_helper) != 0) { 3605 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3606 } 3607 } 3608 3609 // initialize thread priority policy 3610 prio_init(); 3611 3612 #ifdef __APPLE__ 3613 // dynamically link to objective c gc registration 3614 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3615 if (handleLibObjc != NULL) { 3616 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3617 } 3618 #endif 3619 3620 return JNI_OK; 3621 } 3622 3623 // Mark the polling page as unreadable 3624 void os::make_polling_page_unreadable(void) { 3625 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3626 fatal("Could not disable polling page"); 3627 } 3628 } 3629 3630 // Mark the polling page as readable 3631 void os::make_polling_page_readable(void) { 3632 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3633 fatal("Could not enable polling page"); 3634 } 3635 } 3636 3637 int os::active_processor_count() { 3638 return _processor_count; 3639 } 3640 3641 void os::set_native_thread_name(const char *name) { 3642 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3643 // This is only supported in Snow Leopard and beyond 3644 if (name != NULL) { 3645 // Add a "Java: " prefix to the name 3646 char buf[MAXTHREADNAMESIZE]; 3647 snprintf(buf, sizeof(buf), "Java: %s", name); 3648 pthread_setname_np(buf); 3649 } 3650 #endif 3651 } 3652 3653 bool os::distribute_processes(uint length, uint* distribution) { 3654 // Not yet implemented. 3655 return false; 3656 } 3657 3658 bool os::bind_to_processor(uint processor_id) { 3659 // Not yet implemented. 3660 return false; 3661 } 3662 3663 void os::SuspendedThreadTask::internal_do_task() { 3664 if (do_suspend(_thread->osthread())) { 3665 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3666 do_task(context); 3667 do_resume(_thread->osthread()); 3668 } 3669 } 3670 3671 /// 3672 class PcFetcher : public os::SuspendedThreadTask { 3673 public: 3674 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3675 ExtendedPC result(); 3676 protected: 3677 void do_task(const os::SuspendedThreadTaskContext& context); 3678 private: 3679 ExtendedPC _epc; 3680 }; 3681 3682 ExtendedPC PcFetcher::result() { 3683 guarantee(is_done(), "task is not done yet."); 3684 return _epc; 3685 } 3686 3687 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3688 Thread* thread = context.thread(); 3689 OSThread* osthread = thread->osthread(); 3690 if (osthread->ucontext() != NULL) { 3691 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3692 } else { 3693 // NULL context is unexpected, double-check this is the VMThread 3694 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3695 } 3696 } 3697 3698 // Suspends the target using the signal mechanism and then grabs the PC before 3699 // resuming the target. Used by the flat-profiler only 3700 ExtendedPC os::get_thread_pc(Thread* thread) { 3701 // Make sure that it is called by the watcher for the VMThread 3702 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3703 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3704 3705 PcFetcher fetcher(thread); 3706 fetcher.run(); 3707 return fetcher.result(); 3708 } 3709 3710 //////////////////////////////////////////////////////////////////////////////// 3711 // debug support 3712 3713 bool os::find(address addr, outputStream* st) { 3714 Dl_info dlinfo; 3715 memset(&dlinfo, 0, sizeof(dlinfo)); 3716 if (dladdr(addr, &dlinfo) != 0) { 3717 st->print(PTR_FORMAT ": ", addr); 3718 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3719 st->print("%s+%#x", dlinfo.dli_sname, 3720 addr - (intptr_t)dlinfo.dli_saddr); 3721 } else if (dlinfo.dli_fbase != NULL) { 3722 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3723 } else { 3724 st->print("<absolute address>"); 3725 } 3726 if (dlinfo.dli_fname != NULL) { 3727 st->print(" in %s", dlinfo.dli_fname); 3728 } 3729 if (dlinfo.dli_fbase != NULL) { 3730 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3731 } 3732 st->cr(); 3733 3734 if (Verbose) { 3735 // decode some bytes around the PC 3736 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3737 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3738 address lowest = (address) dlinfo.dli_sname; 3739 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3740 if (begin < lowest) begin = lowest; 3741 Dl_info dlinfo2; 3742 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3743 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3744 end = (address) dlinfo2.dli_saddr; 3745 } 3746 Disassembler::decode(begin, end, st); 3747 } 3748 return true; 3749 } 3750 return false; 3751 } 3752 3753 //////////////////////////////////////////////////////////////////////////////// 3754 // misc 3755 3756 // This does not do anything on Bsd. This is basically a hook for being 3757 // able to use structured exception handling (thread-local exception filters) 3758 // on, e.g., Win32. 3759 void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3760 methodHandle* method, JavaCallArguments* args, 3761 Thread* thread) { 3762 f(value, method, args, thread); 3763 } 3764 3765 void os::print_statistics() { 3766 } 3767 3768 int os::message_box(const char* title, const char* message) { 3769 int i; 3770 fdStream err(defaultStream::error_fd()); 3771 for (i = 0; i < 78; i++) err.print_raw("="); 3772 err.cr(); 3773 err.print_raw_cr(title); 3774 for (i = 0; i < 78; i++) err.print_raw("-"); 3775 err.cr(); 3776 err.print_raw_cr(message); 3777 for (i = 0; i < 78; i++) err.print_raw("="); 3778 err.cr(); 3779 3780 char buf[16]; 3781 // Prevent process from exiting upon "read error" without consuming all CPU 3782 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3783 3784 return buf[0] == 'y' || buf[0] == 'Y'; 3785 } 3786 3787 int os::stat(const char *path, struct stat *sbuf) { 3788 char pathbuf[MAX_PATH]; 3789 if (strlen(path) > MAX_PATH - 1) { 3790 errno = ENAMETOOLONG; 3791 return -1; 3792 } 3793 os::native_path(strcpy(pathbuf, path)); 3794 return ::stat(pathbuf, sbuf); 3795 } 3796 3797 bool os::check_heap(bool force) { 3798 return true; 3799 } 3800 3801 // Is a (classpath) directory empty? 3802 bool os::dir_is_empty(const char* path) { 3803 DIR *dir = NULL; 3804 struct dirent *ptr; 3805 3806 dir = opendir(path); 3807 if (dir == NULL) return true; 3808 3809 // Scan the directory 3810 bool result = true; 3811 char buf[sizeof(struct dirent) + MAX_PATH]; 3812 while (result && (ptr = ::readdir(dir)) != NULL) { 3813 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3814 result = false; 3815 } 3816 } 3817 closedir(dir); 3818 return result; 3819 } 3820 3821 // This code originates from JDK's sysOpen and open64_w 3822 // from src/solaris/hpi/src/system_md.c 3823 3824 int os::open(const char *path, int oflag, int mode) { 3825 if (strlen(path) > MAX_PATH - 1) { 3826 errno = ENAMETOOLONG; 3827 return -1; 3828 } 3829 int fd; 3830 3831 fd = ::open(path, oflag, mode); 3832 if (fd == -1) return -1; 3833 3834 // If the open succeeded, the file might still be a directory 3835 { 3836 struct stat buf; 3837 int ret = ::fstat(fd, &buf); 3838 int st_mode = buf.st_mode; 3839 3840 if (ret != -1) { 3841 if ((st_mode & S_IFMT) == S_IFDIR) { 3842 errno = EISDIR; 3843 ::close(fd); 3844 return -1; 3845 } 3846 } else { 3847 ::close(fd); 3848 return -1; 3849 } 3850 } 3851 3852 // All file descriptors that are opened in the JVM and not 3853 // specifically destined for a subprocess should have the 3854 // close-on-exec flag set. If we don't set it, then careless 3rd 3855 // party native code might fork and exec without closing all 3856 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3857 // UNIXProcess.c), and this in turn might: 3858 // 3859 // - cause end-of-file to fail to be detected on some file 3860 // descriptors, resulting in mysterious hangs, or 3861 // 3862 // - might cause an fopen in the subprocess to fail on a system 3863 // suffering from bug 1085341. 3864 // 3865 // (Yes, the default setting of the close-on-exec flag is a Unix 3866 // design flaw) 3867 // 3868 // See: 3869 // 1085341: 32-bit stdio routines should support file descriptors >255 3870 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3871 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3872 // 3873 #ifdef FD_CLOEXEC 3874 { 3875 int flags = ::fcntl(fd, F_GETFD); 3876 if (flags != -1) { 3877 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3878 } 3879 } 3880 #endif 3881 3882 return fd; 3883 } 3884 3885 3886 // create binary file, rewriting existing file if required 3887 int os::create_binary_file(const char* path, bool rewrite_existing) { 3888 int oflags = O_WRONLY | O_CREAT; 3889 if (!rewrite_existing) { 3890 oflags |= O_EXCL; 3891 } 3892 return ::open(path, oflags, S_IREAD | S_IWRITE); 3893 } 3894 3895 // return current position of file pointer 3896 jlong os::current_file_offset(int fd) { 3897 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3898 } 3899 3900 // move file pointer to the specified offset 3901 jlong os::seek_to_file_offset(int fd, jlong offset) { 3902 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3903 } 3904 3905 // This code originates from JDK's sysAvailable 3906 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3907 3908 int os::available(int fd, jlong *bytes) { 3909 jlong cur, end; 3910 int mode; 3911 struct stat buf; 3912 3913 if (::fstat(fd, &buf) >= 0) { 3914 mode = buf.st_mode; 3915 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3916 // XXX: is the following call interruptible? If so, this might 3917 // need to go through the INTERRUPT_IO() wrapper as for other 3918 // blocking, interruptible calls in this file. 3919 int n; 3920 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3921 *bytes = n; 3922 return 1; 3923 } 3924 } 3925 } 3926 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3927 return 0; 3928 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3929 return 0; 3930 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3931 return 0; 3932 } 3933 *bytes = end - cur; 3934 return 1; 3935 } 3936 3937 // Map a block of memory. 3938 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3939 char *addr, size_t bytes, bool read_only, 3940 bool allow_exec) { 3941 int prot; 3942 int flags; 3943 3944 if (read_only) { 3945 prot = PROT_READ; 3946 flags = MAP_SHARED; 3947 } else { 3948 prot = PROT_READ | PROT_WRITE; 3949 flags = MAP_PRIVATE; 3950 } 3951 3952 if (allow_exec) { 3953 prot |= PROT_EXEC; 3954 } 3955 3956 if (addr != NULL) { 3957 flags |= MAP_FIXED; 3958 } 3959 3960 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3961 fd, file_offset); 3962 if (mapped_address == MAP_FAILED) { 3963 return NULL; 3964 } 3965 return mapped_address; 3966 } 3967 3968 3969 // Remap a block of memory. 3970 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3971 char *addr, size_t bytes, bool read_only, 3972 bool allow_exec) { 3973 // same as map_memory() on this OS 3974 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3975 allow_exec); 3976 } 3977 3978 3979 // Unmap a block of memory. 3980 bool os::pd_unmap_memory(char* addr, size_t bytes) { 3981 return munmap(addr, bytes) == 0; 3982 } 3983 3984 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3985 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 3986 // of a thread. 3987 // 3988 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 3989 // the fast estimate available on the platform. 3990 3991 jlong os::current_thread_cpu_time() { 3992 #ifdef __APPLE__ 3993 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 3994 #else 3995 Unimplemented(); 3996 return 0; 3997 #endif 3998 } 3999 4000 jlong os::thread_cpu_time(Thread* thread) { 4001 #ifdef __APPLE__ 4002 return os::thread_cpu_time(thread, true /* user + sys */); 4003 #else 4004 Unimplemented(); 4005 return 0; 4006 #endif 4007 } 4008 4009 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4010 #ifdef __APPLE__ 4011 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4012 #else 4013 Unimplemented(); 4014 return 0; 4015 #endif 4016 } 4017 4018 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4019 #ifdef __APPLE__ 4020 struct thread_basic_info tinfo; 4021 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4022 kern_return_t kr; 4023 thread_t mach_thread; 4024 4025 mach_thread = thread->osthread()->thread_id(); 4026 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4027 if (kr != KERN_SUCCESS) { 4028 return -1; 4029 } 4030 4031 if (user_sys_cpu_time) { 4032 jlong nanos; 4033 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4034 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4035 return nanos; 4036 } else { 4037 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4038 } 4039 #else 4040 Unimplemented(); 4041 return 0; 4042 #endif 4043 } 4044 4045 4046 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4047 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4048 info_ptr->may_skip_backward = false; // elapsed time not wall time 4049 info_ptr->may_skip_forward = false; // elapsed time not wall time 4050 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4051 } 4052 4053 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4054 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4055 info_ptr->may_skip_backward = false; // elapsed time not wall time 4056 info_ptr->may_skip_forward = false; // elapsed time not wall time 4057 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4058 } 4059 4060 bool os::is_thread_cpu_time_supported() { 4061 #ifdef __APPLE__ 4062 return true; 4063 #else 4064 return false; 4065 #endif 4066 } 4067 4068 // System loadavg support. Returns -1 if load average cannot be obtained. 4069 // Bsd doesn't yet have a (official) notion of processor sets, 4070 // so just return the system wide load average. 4071 int os::loadavg(double loadavg[], int nelem) { 4072 return ::getloadavg(loadavg, nelem); 4073 } 4074 4075 void os::pause() { 4076 char filename[MAX_PATH]; 4077 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4078 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4079 } else { 4080 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4081 } 4082 4083 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4084 if (fd != -1) { 4085 struct stat buf; 4086 ::close(fd); 4087 while (::stat(filename, &buf) == 0) { 4088 (void)::poll(NULL, 0, 100); 4089 } 4090 } else { 4091 jio_fprintf(stderr, 4092 "Could not open pause file '%s', continuing immediately.\n", filename); 4093 } 4094 } 4095 4096 4097 // Refer to the comments in os_solaris.cpp park-unpark. The next two 4098 // comment paragraphs are worth repeating here: 4099 // 4100 // Assumption: 4101 // Only one parker can exist on an event, which is why we allocate 4102 // them per-thread. Multiple unparkers can coexist. 4103 // 4104 // _Event serves as a restricted-range semaphore. 4105 // -1 : thread is blocked, i.e. there is a waiter 4106 // 0 : neutral: thread is running or ready, 4107 // could have been signaled after a wait started 4108 // 1 : signaled - thread is running or ready 4109 // 4110 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4111 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4112 // For specifics regarding the bug see GLIBC BUGID 261237 : 4113 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4114 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4115 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4116 // is used. (The simple C test-case provided in the GLIBC bug report manifests the 4117 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4118 // and monitorenter when we're using 1-0 locking. All those operations may result in 4119 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4120 // of libpthread avoids the problem, but isn't practical. 4121 // 4122 // Possible remedies: 4123 // 4124 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4125 // This is palliative and probabilistic, however. If the thread is preempted 4126 // between the call to compute_abstime() and pthread_cond_timedwait(), more 4127 // than the minimum period may have passed, and the abstime may be stale (in the 4128 // past) resultin in a hang. Using this technique reduces the odds of a hang 4129 // but the JVM is still vulnerable, particularly on heavily loaded systems. 4130 // 4131 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4132 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4133 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4134 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4135 // thread. 4136 // 4137 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4138 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4139 // a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4140 // This also works well. In fact it avoids kernel-level scalability impediments 4141 // on certain platforms that don't handle lots of active pthread_cond_timedwait() 4142 // timers in a graceful fashion. 4143 // 4144 // 4. When the abstime value is in the past it appears that control returns 4145 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4146 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4147 // can avoid the problem by reinitializing the condvar -- by cond_destroy() 4148 // followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4149 // It may be possible to avoid reinitialization by checking the return 4150 // value from pthread_cond_timedwait(). In addition to reinitializing the 4151 // condvar we must establish the invariant that cond_signal() is only called 4152 // within critical sections protected by the adjunct mutex. This prevents 4153 // cond_signal() from "seeing" a condvar that's in the midst of being 4154 // reinitialized or that is corrupt. Sadly, this invariant obviates the 4155 // desirable signal-after-unlock optimization that avoids futile context switching. 4156 // 4157 // I'm also concerned that some versions of NTPL might allocate an auxilliary 4158 // structure when a condvar is used or initialized. cond_destroy() would 4159 // release the helper structure. Our reinitialize-after-timedwait fix 4160 // put excessive stress on malloc/free and locks protecting the c-heap. 4161 // 4162 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4163 // It may be possible to refine (4) by checking the kernel and NTPL verisons 4164 // and only enabling the work-around for vulnerable environments. 4165 4166 // utility to compute the abstime argument to timedwait: 4167 // millis is the relative timeout time 4168 // abstime will be the absolute timeout time 4169 // TODO: replace compute_abstime() with unpackTime() 4170 4171 static struct timespec* compute_abstime(struct timespec* abstime, 4172 jlong millis) { 4173 if (millis < 0) millis = 0; 4174 struct timeval now; 4175 int status = gettimeofday(&now, NULL); 4176 assert(status == 0, "gettimeofday"); 4177 jlong seconds = millis / 1000; 4178 millis %= 1000; 4179 if (seconds > 50000000) { // see man cond_timedwait(3T) 4180 seconds = 50000000; 4181 } 4182 abstime->tv_sec = now.tv_sec + seconds; 4183 long usec = now.tv_usec + millis * 1000; 4184 if (usec >= 1000000) { 4185 abstime->tv_sec += 1; 4186 usec -= 1000000; 4187 } 4188 abstime->tv_nsec = usec * 1000; 4189 return abstime; 4190 } 4191 4192 void os::PlatformEvent::park() { // AKA "down()" 4193 // Transitions for _Event: 4194 // -1 => -1 : illegal 4195 // 1 => 0 : pass - return immediately 4196 // 0 => -1 : block; then set _Event to 0 before returning 4197 4198 // Invariant: Only the thread associated with the Event/PlatformEvent 4199 // may call park(). 4200 // TODO: assert that _Assoc != NULL or _Assoc == Self 4201 assert(_nParked == 0, "invariant"); 4202 4203 int v; 4204 for (;;) { 4205 v = _Event; 4206 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4207 } 4208 guarantee(v >= 0, "invariant"); 4209 if (v == 0) { 4210 // Do this the hard way by blocking ... 4211 int status = pthread_mutex_lock(_mutex); 4212 assert_status(status == 0, status, "mutex_lock"); 4213 guarantee(_nParked == 0, "invariant"); 4214 ++_nParked; 4215 while (_Event < 0) { 4216 status = pthread_cond_wait(_cond, _mutex); 4217 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4218 // Treat this the same as if the wait was interrupted 4219 if (status == ETIMEDOUT) { status = EINTR; } 4220 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4221 } 4222 --_nParked; 4223 4224 _Event = 0; 4225 status = pthread_mutex_unlock(_mutex); 4226 assert_status(status == 0, status, "mutex_unlock"); 4227 // Paranoia to ensure our locked and lock-free paths interact 4228 // correctly with each other. 4229 OrderAccess::fence(); 4230 } 4231 guarantee(_Event >= 0, "invariant"); 4232 } 4233 4234 int os::PlatformEvent::park(jlong millis) { 4235 // Transitions for _Event: 4236 // -1 => -1 : illegal 4237 // 1 => 0 : pass - return immediately 4238 // 0 => -1 : block; then set _Event to 0 before returning 4239 4240 guarantee(_nParked == 0, "invariant"); 4241 4242 int v; 4243 for (;;) { 4244 v = _Event; 4245 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4246 } 4247 guarantee(v >= 0, "invariant"); 4248 if (v != 0) return OS_OK; 4249 4250 // We do this the hard way, by blocking the thread. 4251 // Consider enforcing a minimum timeout value. 4252 struct timespec abst; 4253 compute_abstime(&abst, millis); 4254 4255 int ret = OS_TIMEOUT; 4256 int status = pthread_mutex_lock(_mutex); 4257 assert_status(status == 0, status, "mutex_lock"); 4258 guarantee(_nParked == 0, "invariant"); 4259 ++_nParked; 4260 4261 // Object.wait(timo) will return because of 4262 // (a) notification 4263 // (b) timeout 4264 // (c) thread.interrupt 4265 // 4266 // Thread.interrupt and object.notify{All} both call Event::set. 4267 // That is, we treat thread.interrupt as a special case of notification. 4268 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4269 // We assume all ETIME returns are valid. 4270 // 4271 // TODO: properly differentiate simultaneous notify+interrupt. 4272 // In that case, we should propagate the notify to another waiter. 4273 4274 while (_Event < 0) { 4275 status = pthread_cond_timedwait(_cond, _mutex, &abst); 4276 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4277 pthread_cond_destroy(_cond); 4278 pthread_cond_init(_cond, NULL); 4279 } 4280 assert_status(status == 0 || status == EINTR || 4281 status == ETIMEDOUT, 4282 status, "cond_timedwait"); 4283 if (!FilterSpuriousWakeups) break; // previous semantics 4284 if (status == ETIMEDOUT) break; 4285 // We consume and ignore EINTR and spurious wakeups. 4286 } 4287 --_nParked; 4288 if (_Event >= 0) { 4289 ret = OS_OK; 4290 } 4291 _Event = 0; 4292 status = pthread_mutex_unlock(_mutex); 4293 assert_status(status == 0, status, "mutex_unlock"); 4294 assert(_nParked == 0, "invariant"); 4295 // Paranoia to ensure our locked and lock-free paths interact 4296 // correctly with each other. 4297 OrderAccess::fence(); 4298 return ret; 4299 } 4300 4301 void os::PlatformEvent::unpark() { 4302 // Transitions for _Event: 4303 // 0 => 1 : just return 4304 // 1 => 1 : just return 4305 // -1 => either 0 or 1; must signal target thread 4306 // That is, we can safely transition _Event from -1 to either 4307 // 0 or 1. 4308 // See also: "Semaphores in Plan 9" by Mullender & Cox 4309 // 4310 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4311 // that it will take two back-to-back park() calls for the owning 4312 // thread to block. This has the benefit of forcing a spurious return 4313 // from the first park() call after an unpark() call which will help 4314 // shake out uses of park() and unpark() without condition variables. 4315 4316 if (Atomic::xchg(1, &_Event) >= 0) return; 4317 4318 // Wait for the thread associated with the event to vacate 4319 int status = pthread_mutex_lock(_mutex); 4320 assert_status(status == 0, status, "mutex_lock"); 4321 int AnyWaiters = _nParked; 4322 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4323 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4324 AnyWaiters = 0; 4325 pthread_cond_signal(_cond); 4326 } 4327 status = pthread_mutex_unlock(_mutex); 4328 assert_status(status == 0, status, "mutex_unlock"); 4329 if (AnyWaiters != 0) { 4330 // Note that we signal() *after* dropping the lock for "immortal" Events. 4331 // This is safe and avoids a common class of futile wakeups. In rare 4332 // circumstances this can cause a thread to return prematurely from 4333 // cond_{timed}wait() but the spurious wakeup is benign and the victim 4334 // will simply re-test the condition and re-park itself. 4335 // This provides particular benefit if the underlying platform does not 4336 // provide wait morphing. 4337 status = pthread_cond_signal(_cond); 4338 assert_status(status == 0, status, "cond_signal"); 4339 } 4340 } 4341 4342 4343 // JSR166 4344 // ------------------------------------------------------- 4345 4346 // The solaris and bsd implementations of park/unpark are fairly 4347 // conservative for now, but can be improved. They currently use a 4348 // mutex/condvar pair, plus a a count. 4349 // Park decrements count if > 0, else does a condvar wait. Unpark 4350 // sets count to 1 and signals condvar. Only one thread ever waits 4351 // on the condvar. Contention seen when trying to park implies that someone 4352 // is unparking you, so don't wait. And spurious returns are fine, so there 4353 // is no need to track notifications. 4354 4355 #define MAX_SECS 100000000 4356 4357 // This code is common to bsd and solaris and will be moved to a 4358 // common place in dolphin. 4359 // 4360 // The passed in time value is either a relative time in nanoseconds 4361 // or an absolute time in milliseconds. Either way it has to be unpacked 4362 // into suitable seconds and nanoseconds components and stored in the 4363 // given timespec structure. 4364 // Given time is a 64-bit value and the time_t used in the timespec is only 4365 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4366 // overflow if times way in the future are given. Further on Solaris versions 4367 // prior to 10 there is a restriction (see cond_timedwait) that the specified 4368 // number of seconds, in abstime, is less than current_time + 100,000,000. 4369 // As it will be 28 years before "now + 100000000" will overflow we can 4370 // ignore overflow and just impose a hard-limit on seconds using the value 4371 // of "now + 100,000,000". This places a limit on the timeout of about 3.17 4372 // years from "now". 4373 4374 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4375 assert(time > 0, "convertTime"); 4376 4377 struct timeval now; 4378 int status = gettimeofday(&now, NULL); 4379 assert(status == 0, "gettimeofday"); 4380 4381 time_t max_secs = now.tv_sec + MAX_SECS; 4382 4383 if (isAbsolute) { 4384 jlong secs = time / 1000; 4385 if (secs > max_secs) { 4386 absTime->tv_sec = max_secs; 4387 } else { 4388 absTime->tv_sec = secs; 4389 } 4390 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4391 } else { 4392 jlong secs = time / NANOSECS_PER_SEC; 4393 if (secs >= MAX_SECS) { 4394 absTime->tv_sec = max_secs; 4395 absTime->tv_nsec = 0; 4396 } else { 4397 absTime->tv_sec = now.tv_sec + secs; 4398 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4399 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4400 absTime->tv_nsec -= NANOSECS_PER_SEC; 4401 ++absTime->tv_sec; // note: this must be <= max_secs 4402 } 4403 } 4404 } 4405 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4406 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4407 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4408 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4409 } 4410 4411 void Parker::park(bool isAbsolute, jlong time) { 4412 // Ideally we'd do something useful while spinning, such 4413 // as calling unpackTime(). 4414 4415 // Optional fast-path check: 4416 // Return immediately if a permit is available. 4417 // We depend on Atomic::xchg() having full barrier semantics 4418 // since we are doing a lock-free update to _counter. 4419 if (Atomic::xchg(0, &_counter) > 0) return; 4420 4421 Thread* thread = Thread::current(); 4422 assert(thread->is_Java_thread(), "Must be JavaThread"); 4423 JavaThread *jt = (JavaThread *)thread; 4424 4425 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4426 // Check interrupt before trying to wait 4427 if (Thread::is_interrupted(thread, false)) { 4428 return; 4429 } 4430 4431 // Next, demultiplex/decode time arguments 4432 struct timespec absTime; 4433 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4434 return; 4435 } 4436 if (time > 0) { 4437 unpackTime(&absTime, isAbsolute, time); 4438 } 4439 4440 4441 // Enter safepoint region 4442 // Beware of deadlocks such as 6317397. 4443 // The per-thread Parker:: mutex is a classic leaf-lock. 4444 // In particular a thread must never block on the Threads_lock while 4445 // holding the Parker:: mutex. If safepoints are pending both the 4446 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4447 ThreadBlockInVM tbivm(jt); 4448 4449 // Don't wait if cannot get lock since interference arises from 4450 // unblocking. Also. check interrupt before trying wait 4451 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4452 return; 4453 } 4454 4455 int status; 4456 if (_counter > 0) { // no wait needed 4457 _counter = 0; 4458 status = pthread_mutex_unlock(_mutex); 4459 assert(status == 0, "invariant"); 4460 // Paranoia to ensure our locked and lock-free paths interact 4461 // correctly with each other and Java-level accesses. 4462 OrderAccess::fence(); 4463 return; 4464 } 4465 4466 #ifdef ASSERT 4467 // Don't catch signals while blocked; let the running threads have the signals. 4468 // (This allows a debugger to break into the running thread.) 4469 sigset_t oldsigs; 4470 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4471 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4472 #endif 4473 4474 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4475 jt->set_suspend_equivalent(); 4476 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4477 4478 if (time == 0) { 4479 status = pthread_cond_wait(_cond, _mutex); 4480 } else { 4481 status = pthread_cond_timedwait(_cond, _mutex, &absTime); 4482 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4483 pthread_cond_destroy(_cond); 4484 pthread_cond_init(_cond, NULL); 4485 } 4486 } 4487 assert_status(status == 0 || status == EINTR || 4488 status == ETIMEDOUT, 4489 status, "cond_timedwait"); 4490 4491 #ifdef ASSERT 4492 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4493 #endif 4494 4495 _counter = 0; 4496 status = pthread_mutex_unlock(_mutex); 4497 assert_status(status == 0, status, "invariant"); 4498 // Paranoia to ensure our locked and lock-free paths interact 4499 // correctly with each other and Java-level accesses. 4500 OrderAccess::fence(); 4501 4502 // If externally suspended while waiting, re-suspend 4503 if (jt->handle_special_suspend_equivalent_condition()) { 4504 jt->java_suspend_self(); 4505 } 4506 } 4507 4508 void Parker::unpark() { 4509 int status = pthread_mutex_lock(_mutex); 4510 assert(status == 0, "invariant"); 4511 const int s = _counter; 4512 _counter = 1; 4513 if (s < 1) { 4514 if (WorkAroundNPTLTimedWaitHang) { 4515 status = pthread_cond_signal(_cond); 4516 assert(status == 0, "invariant"); 4517 status = pthread_mutex_unlock(_mutex); 4518 assert(status == 0, "invariant"); 4519 } else { 4520 status = pthread_mutex_unlock(_mutex); 4521 assert(status == 0, "invariant"); 4522 status = pthread_cond_signal(_cond); 4523 assert(status == 0, "invariant"); 4524 } 4525 } else { 4526 pthread_mutex_unlock(_mutex); 4527 assert(status == 0, "invariant"); 4528 } 4529 } 4530 4531 4532 // Darwin has no "environ" in a dynamic library. 4533 #ifdef __APPLE__ 4534 #include <crt_externs.h> 4535 #define environ (*_NSGetEnviron()) 4536 #else 4537 extern char** environ; 4538 #endif 4539 4540 // Run the specified command in a separate process. Return its exit value, 4541 // or -1 on failure (e.g. can't fork a new process). 4542 // Unlike system(), this function can be called from signal handler. It 4543 // doesn't block SIGINT et al. 4544 int os::fork_and_exec(char* cmd) { 4545 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4546 4547 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4548 // pthread_atfork handlers and reset pthread library. All we need is a 4549 // separate process to execve. Make a direct syscall to fork process. 4550 // On IA64 there's no fork syscall, we have to use fork() and hope for 4551 // the best... 4552 pid_t pid = fork(); 4553 4554 if (pid < 0) { 4555 // fork failed 4556 return -1; 4557 4558 } else if (pid == 0) { 4559 // child process 4560 4561 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4562 // first to kill every thread on the thread list. Because this list is 4563 // not reset by fork() (see notes above), execve() will instead kill 4564 // every thread in the parent process. We know this is the only thread 4565 // in the new process, so make a system call directly. 4566 // IA64 should use normal execve() from glibc to match the glibc fork() 4567 // above. 4568 execve("/bin/sh", (char* const*)argv, environ); 4569 4570 // execve failed 4571 _exit(-1); 4572 4573 } else { 4574 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4575 // care about the actual exit code, for now. 4576 4577 int status; 4578 4579 // Wait for the child process to exit. This returns immediately if 4580 // the child has already exited. */ 4581 while (waitpid(pid, &status, 0) < 0) { 4582 switch (errno) { 4583 case ECHILD: return 0; 4584 case EINTR: break; 4585 default: return -1; 4586 } 4587 } 4588 4589 if (WIFEXITED(status)) { 4590 // The child exited normally; get its exit code. 4591 return WEXITSTATUS(status); 4592 } else if (WIFSIGNALED(status)) { 4593 // The child exited because of a signal 4594 // The best value to return is 0x80 + signal number, 4595 // because that is what all Unix shells do, and because 4596 // it allows callers to distinguish between process exit and 4597 // process death by signal. 4598 return 0x80 + WTERMSIG(status); 4599 } else { 4600 // Unknown exit code; pass it through 4601 return status; 4602 } 4603 } 4604 } 4605 4606 // is_headless_jre() 4607 // 4608 // Test for the existence of xawt/libmawt.so or libawt_xawt.so 4609 // in order to report if we are running in a headless jre 4610 // 4611 // Since JDK8 xawt/libmawt.so was moved into the same directory 4612 // as libawt.so, and renamed libawt_xawt.so 4613 // 4614 bool os::is_headless_jre() { 4615 #ifdef __APPLE__ 4616 // We no longer build headless-only on Mac OS X 4617 return false; 4618 #else 4619 struct stat statbuf; 4620 char buf[MAXPATHLEN]; 4621 char libmawtpath[MAXPATHLEN]; 4622 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4623 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4624 char *p; 4625 4626 // Get path to libjvm.so 4627 os::jvm_path(buf, sizeof(buf)); 4628 4629 // Get rid of libjvm.so 4630 p = strrchr(buf, '/'); 4631 if (p == NULL) { 4632 return false; 4633 } else { 4634 *p = '\0'; 4635 } 4636 4637 // Get rid of client or server 4638 p = strrchr(buf, '/'); 4639 if (p == NULL) { 4640 return false; 4641 } else { 4642 *p = '\0'; 4643 } 4644 4645 // check xawt/libmawt.so 4646 strcpy(libmawtpath, buf); 4647 strcat(libmawtpath, xawtstr); 4648 if (::stat(libmawtpath, &statbuf) == 0) return false; 4649 4650 // check libawt_xawt.so 4651 strcpy(libmawtpath, buf); 4652 strcat(libmawtpath, new_xawtstr); 4653 if (::stat(libmawtpath, &statbuf) == 0) return false; 4654 4655 return true; 4656 #endif 4657 } 4658 4659 // Get the default path to the core file 4660 // Returns the length of the string 4661 int os::get_core_path(char* buffer, size_t bufferSize) { 4662 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 4663 4664 // Truncate if theoretical string was longer than bufferSize 4665 n = MIN2(n, (int)bufferSize); 4666 4667 return n; 4668 } 4669 4670 #ifndef PRODUCT 4671 void TestReserveMemorySpecial_test() { 4672 // No tests available for this platform 4673 } 4674 #endif