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