1 /* 2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "classfile/classLoader.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/vmSymbols.hpp" 29 #include "code/icBuffer.hpp" 30 #include "code/vtableStubs.hpp" 31 #include "compiler/compileBroker.hpp" 32 #include "compiler/disassembler.hpp" 33 #include "interpreter/interpreter.hpp" 34 #include "jvm_bsd.h" 35 #include "memory/allocation.inline.hpp" 36 #include "memory/filemap.hpp" 37 #include "mutex_bsd.inline.hpp" 38 #include "oops/oop.inline.hpp" 39 #include "os_bsd.inline.hpp" 40 #include "os_share_bsd.hpp" 41 #include "prims/jniFastGetField.hpp" 42 #include "prims/jvm.h" 43 #include "prims/jvm_misc.hpp" 44 #include "runtime/arguments.hpp" 45 #include "runtime/atomic.inline.hpp" 46 #include "runtime/extendedPC.hpp" 47 #include "runtime/globals.hpp" 48 #include "runtime/interfaceSupport.hpp" 49 #include "runtime/java.hpp" 50 #include "runtime/javaCalls.hpp" 51 #include "runtime/mutexLocker.hpp" 52 #include "runtime/objectMonitor.hpp" 53 #include "runtime/orderAccess.inline.hpp" 54 #include "runtime/osThread.hpp" 55 #include "runtime/perfMemory.hpp" 56 #include "runtime/sharedRuntime.hpp" 57 #include "runtime/statSampler.hpp" 58 #include "runtime/stubRoutines.hpp" 59 #include "runtime/thread.inline.hpp" 60 #include "runtime/threadCritical.hpp" 61 #include "runtime/timer.hpp" 62 #include "semaphore_bsd.hpp" 63 #include "services/attachListener.hpp" 64 #include "services/memTracker.hpp" 65 #include "services/runtimeService.hpp" 66 #include "utilities/decoder.hpp" 67 #include "utilities/defaultStream.hpp" 68 #include "utilities/events.hpp" 69 #include "utilities/growableArray.hpp" 70 #include "utilities/vmError.hpp" 71 72 // put OS-includes here 73 # include <sys/types.h> 74 # include <sys/mman.h> 75 # include <sys/stat.h> 76 # include <sys/select.h> 77 # include <pthread.h> 78 # include <signal.h> 79 # include <errno.h> 80 # include <dlfcn.h> 81 # include <stdio.h> 82 # include <unistd.h> 83 # include <sys/resource.h> 84 # include <pthread.h> 85 # include <sys/stat.h> 86 # include <sys/time.h> 87 # include <sys/times.h> 88 # include <sys/utsname.h> 89 # include <sys/socket.h> 90 # include <sys/wait.h> 91 # include <time.h> 92 # include <pwd.h> 93 # include <poll.h> 94 # include <semaphore.h> 95 # include <fcntl.h> 96 # include <string.h> 97 # include <sys/param.h> 98 # include <sys/sysctl.h> 99 # include <sys/ipc.h> 100 # include <sys/shm.h> 101 #ifndef __APPLE__ 102 # include <link.h> 103 #endif 104 # include <stdint.h> 105 # include <inttypes.h> 106 # include <sys/ioctl.h> 107 # include <sys/syscall.h> 108 109 #if defined(__FreeBSD__) || defined(__NetBSD__) 110 #include <elf.h> 111 #endif 112 113 #ifdef __APPLE__ 114 #include <mach/mach.h> // semaphore_* API 115 #include <mach-o/dyld.h> 116 #include <sys/proc_info.h> 117 #include <objc/objc-auto.h> 118 #endif 119 120 #ifndef MAP_ANONYMOUS 121 #define MAP_ANONYMOUS MAP_ANON 122 #endif 123 124 #define MAX_PATH (2 * K) 125 126 // for timer info max values which include all bits 127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 128 129 #define LARGEPAGES_BIT (1 << 6) 130 131 //////////////////////////////////////////////////////////////////////////////// 132 // global variables 133 julong os::Bsd::_physical_memory = 0; 134 135 #ifdef __APPLE__ 136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 137 volatile uint64_t os::Bsd::_max_abstime = 0; 138 #else 139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 140 #endif 141 pthread_t os::Bsd::_main_thread; 142 int os::Bsd::_page_size = -1; 143 144 static jlong initial_time_count=0; 145 146 static int clock_tics_per_sec = 100; 147 148 // For diagnostics to print a message once. see run_periodic_checks 149 static sigset_t check_signal_done; 150 static bool check_signals = true; 151 152 static pid_t _initial_pid = 0; 153 154 // Signal number used to suspend/resume a thread 155 156 // do not use any signal number less than SIGSEGV, see 4355769 157 static int SR_signum = SIGUSR2; 158 sigset_t SR_sigset; 159 160 161 //////////////////////////////////////////////////////////////////////////////// 162 // utility functions 163 164 static int SR_initialize(); 165 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 166 167 julong os::available_memory() { 168 return Bsd::available_memory(); 169 } 170 171 // available here means free 172 julong os::Bsd::available_memory() { 173 uint64_t available = physical_memory() >> 2; 174 #ifdef __APPLE__ 175 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 176 vm_statistics64_data_t vmstat; 177 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 178 (host_info64_t)&vmstat, &count); 179 assert(kerr == KERN_SUCCESS, 180 "host_statistics64 failed - check mach_host_self() and count"); 181 if (kerr == KERN_SUCCESS) { 182 available = vmstat.free_count * os::vm_page_size(); 183 } 184 #endif 185 return available; 186 } 187 188 julong os::physical_memory() { 189 return Bsd::physical_memory(); 190 } 191 192 // Return true if user is running as root. 193 194 bool os::have_special_privileges() { 195 static bool init = false; 196 static bool privileges = false; 197 if (!init) { 198 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 199 init = true; 200 } 201 return privileges; 202 } 203 204 205 206 // Cpu architecture string 207 #if defined(ZERO) 208 static char cpu_arch[] = ZERO_LIBARCH; 209 #elif defined(IA64) 210 static char cpu_arch[] = "ia64"; 211 #elif defined(IA32) 212 static char cpu_arch[] = "i386"; 213 #elif defined(AMD64) 214 static char cpu_arch[] = "amd64"; 215 #elif defined(ARM) 216 static char cpu_arch[] = "arm"; 217 #elif defined(PPC32) 218 static char cpu_arch[] = "ppc"; 219 #elif defined(SPARC) 220 #ifdef _LP64 221 static char cpu_arch[] = "sparcv9"; 222 #else 223 static char cpu_arch[] = "sparc"; 224 #endif 225 #else 226 #error Add appropriate cpu_arch setting 227 #endif 228 229 // Compiler variant 230 #ifdef COMPILER2 231 #define COMPILER_VARIANT "server" 232 #else 233 #define COMPILER_VARIANT "client" 234 #endif 235 236 237 void os::Bsd::initialize_system_info() { 238 int mib[2]; 239 size_t len; 240 int cpu_val; 241 julong mem_val; 242 243 // get processors count via hw.ncpus sysctl 244 mib[0] = CTL_HW; 245 mib[1] = HW_NCPU; 246 len = sizeof(cpu_val); 247 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 248 assert(len == sizeof(cpu_val), "unexpected data size"); 249 set_processor_count(cpu_val); 250 } else { 251 set_processor_count(1); // fallback 252 } 253 254 // get physical memory via hw.memsize sysctl (hw.memsize is used 255 // since it returns a 64 bit value) 256 mib[0] = CTL_HW; 257 258 #if defined (HW_MEMSIZE) // Apple 259 mib[1] = HW_MEMSIZE; 260 #elif defined(HW_PHYSMEM) // Most of BSD 261 mib[1] = HW_PHYSMEM; 262 #elif defined(HW_REALMEM) // Old FreeBSD 263 mib[1] = HW_REALMEM; 264 #else 265 #error No ways to get physmem 266 #endif 267 268 len = sizeof(mem_val); 269 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 270 assert(len == sizeof(mem_val), "unexpected data size"); 271 _physical_memory = mem_val; 272 } else { 273 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 274 } 275 276 #ifdef __OpenBSD__ 277 { 278 // limit _physical_memory memory view on OpenBSD since 279 // datasize rlimit restricts us anyway. 280 struct rlimit limits; 281 getrlimit(RLIMIT_DATA, &limits); 282 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 283 } 284 #endif 285 } 286 287 #ifdef __APPLE__ 288 static const char *get_home() { 289 const char *home_dir = ::getenv("HOME"); 290 if ((home_dir == NULL) || (*home_dir == '\0')) { 291 struct passwd *passwd_info = getpwuid(geteuid()); 292 if (passwd_info != NULL) { 293 home_dir = passwd_info->pw_dir; 294 } 295 } 296 297 return home_dir; 298 } 299 #endif 300 301 void os::init_system_properties_values() { 302 // The next steps are taken in the product version: 303 // 304 // Obtain the JAVA_HOME value from the location of libjvm.so. 305 // This library should be located at: 306 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 307 // 308 // If "/jre/lib/" appears at the right place in the path, then we 309 // assume libjvm.so is installed in a JDK and we use this path. 310 // 311 // Otherwise exit with message: "Could not create the Java virtual machine." 312 // 313 // The following extra steps are taken in the debugging version: 314 // 315 // If "/jre/lib/" does NOT appear at the right place in the path 316 // instead of exit check for $JAVA_HOME environment variable. 317 // 318 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 319 // then we append a fake suffix "hotspot/libjvm.so" to this path so 320 // it looks like libjvm.so is installed there 321 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 322 // 323 // Otherwise exit. 324 // 325 // Important note: if the location of libjvm.so changes this 326 // code needs to be changed accordingly. 327 328 // See ld(1): 329 // The linker uses the following search paths to locate required 330 // shared libraries: 331 // 1: ... 332 // ... 333 // 7: The default directories, normally /lib and /usr/lib. 334 #ifndef DEFAULT_LIBPATH 335 #define DEFAULT_LIBPATH "/lib:/usr/lib" 336 #endif 337 338 // Base path of extensions installed on the system. 339 #define SYS_EXT_DIR "/usr/java/packages" 340 #define EXTENSIONS_DIR "/lib/ext" 341 342 #ifndef __APPLE__ 343 344 // Buffer that fits several sprintfs. 345 // Note that the space for the colon and the trailing null are provided 346 // by the nulls included by the sizeof operator. 347 const size_t bufsize = 348 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 349 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 350 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 351 352 // sysclasspath, java_home, dll_dir 353 { 354 char *pslash; 355 os::jvm_path(buf, bufsize); 356 357 // Found the full path to libjvm.so. 358 // Now cut the path to <java_home>/jre if we can. 359 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 360 pslash = strrchr(buf, '/'); 361 if (pslash != NULL) { 362 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 363 } 364 Arguments::set_dll_dir(buf); 365 366 if (pslash != NULL) { 367 pslash = strrchr(buf, '/'); 368 if (pslash != NULL) { 369 *pslash = '\0'; // Get rid of /<arch>. 370 pslash = strrchr(buf, '/'); 371 if (pslash != NULL) { 372 *pslash = '\0'; // Get rid of /lib. 373 } 374 } 375 } 376 Arguments::set_java_home(buf); 377 set_boot_path('/', ':'); 378 } 379 380 // Where to look for native libraries. 381 // 382 // Note: Due to a legacy implementation, most of the library path 383 // is set in the launcher. This was to accomodate linking restrictions 384 // on legacy Bsd implementations (which are no longer supported). 385 // Eventually, all the library path setting will be done here. 386 // 387 // However, to prevent the proliferation of improperly built native 388 // libraries, the new path component /usr/java/packages is added here. 389 // Eventually, all the library path setting will be done here. 390 { 391 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 392 // should always exist (until the legacy problem cited above is 393 // addressed). 394 const char *v = ::getenv("LD_LIBRARY_PATH"); 395 const char *v_colon = ":"; 396 if (v == NULL) { v = ""; v_colon = ""; } 397 // That's +1 for the colon and +1 for the trailing '\0'. 398 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 399 strlen(v) + 1 + 400 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 401 mtInternal); 402 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 403 Arguments::set_library_path(ld_library_path); 404 FREE_C_HEAP_ARRAY(char, ld_library_path); 405 } 406 407 // Extensions directories. 408 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 409 Arguments::set_ext_dirs(buf); 410 411 FREE_C_HEAP_ARRAY(char, buf); 412 413 #else // __APPLE__ 414 415 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 416 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 417 418 const char *user_home_dir = get_home(); 419 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 420 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 421 sizeof(SYS_EXTENSIONS_DIRS); 422 423 // Buffer that fits several sprintfs. 424 // Note that the space for the colon and the trailing null are provided 425 // by the nulls included by the sizeof operator. 426 const size_t bufsize = 427 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 428 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 429 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 430 431 // sysclasspath, java_home, dll_dir 432 { 433 char *pslash; 434 os::jvm_path(buf, bufsize); 435 436 // Found the full path to libjvm.so. 437 // Now cut the path to <java_home>/jre if we can. 438 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 439 pslash = strrchr(buf, '/'); 440 if (pslash != NULL) { 441 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 442 } 443 #ifdef STATIC_BUILD 444 strcat(buf, "/lib"); 445 #endif 446 447 Arguments::set_dll_dir(buf); 448 449 if (pslash != NULL) { 450 pslash = strrchr(buf, '/'); 451 if (pslash != NULL) { 452 *pslash = '\0'; // Get rid of /lib. 453 } 454 } 455 Arguments::set_java_home(buf); 456 set_boot_path('/', ':'); 457 } 458 459 // Where to look for native libraries. 460 // 461 // Note: Due to a legacy implementation, most of the library path 462 // is set in the launcher. This was to accomodate linking restrictions 463 // on legacy Bsd implementations (which are no longer supported). 464 // Eventually, all the library path setting will be done here. 465 // 466 // However, to prevent the proliferation of improperly built native 467 // libraries, the new path component /usr/java/packages is added here. 468 // Eventually, all the library path setting will be done here. 469 { 470 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 471 // should always exist (until the legacy problem cited above is 472 // addressed). 473 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 474 // can specify a directory inside an app wrapper 475 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 476 const char *l_colon = ":"; 477 if (l == NULL) { l = ""; l_colon = ""; } 478 479 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 480 const char *v_colon = ":"; 481 if (v == NULL) { v = ""; v_colon = ""; } 482 483 // Apple's Java6 has "." at the beginning of java.library.path. 484 // OpenJDK on Windows has "." at the end of java.library.path. 485 // OpenJDK on Linux and Solaris don't have "." in java.library.path 486 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 487 // "." is appended to the end of java.library.path. Yes, this 488 // could cause a change in behavior, but Apple's Java6 behavior 489 // can be achieved by putting "." at the beginning of the 490 // JAVA_LIBRARY_PATH environment variable. 491 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 492 strlen(v) + 1 + strlen(l) + 1 + 493 system_ext_size + 3, 494 mtInternal); 495 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 496 v, v_colon, l, l_colon, user_home_dir); 497 Arguments::set_library_path(ld_library_path); 498 FREE_C_HEAP_ARRAY(char, ld_library_path); 499 } 500 501 // Extensions directories. 502 // 503 // Note that the space for the colon and the trailing null are provided 504 // by the nulls included by the sizeof operator (so actually one byte more 505 // than necessary is allocated). 506 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 507 user_home_dir, Arguments::get_java_home()); 508 Arguments::set_ext_dirs(buf); 509 510 FREE_C_HEAP_ARRAY(char, buf); 511 512 #undef SYS_EXTENSIONS_DIR 513 #undef SYS_EXTENSIONS_DIRS 514 515 #endif // __APPLE__ 516 517 #undef SYS_EXT_DIR 518 #undef EXTENSIONS_DIR 519 } 520 521 //////////////////////////////////////////////////////////////////////////////// 522 // breakpoint support 523 524 void os::breakpoint() { 525 BREAKPOINT; 526 } 527 528 extern "C" void breakpoint() { 529 // use debugger to set breakpoint here 530 } 531 532 //////////////////////////////////////////////////////////////////////////////// 533 // signal support 534 535 debug_only(static bool signal_sets_initialized = false); 536 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 537 538 bool os::Bsd::is_sig_ignored(int sig) { 539 struct sigaction oact; 540 sigaction(sig, (struct sigaction*)NULL, &oact); 541 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 542 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 543 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) { 544 return true; 545 } else { 546 return false; 547 } 548 } 549 550 void os::Bsd::signal_sets_init() { 551 // Should also have an assertion stating we are still single-threaded. 552 assert(!signal_sets_initialized, "Already initialized"); 553 // Fill in signals that are necessarily unblocked for all threads in 554 // the VM. Currently, we unblock the following signals: 555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 556 // by -Xrs (=ReduceSignalUsage)); 557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 559 // the dispositions or masks wrt these signals. 560 // Programs embedding the VM that want to use the above signals for their 561 // own purposes must, at this time, use the "-Xrs" option to prevent 562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 563 // (See bug 4345157, and other related bugs). 564 // In reality, though, unblocking these signals is really a nop, since 565 // these signals are not blocked by default. 566 sigemptyset(&unblocked_sigs); 567 sigemptyset(&allowdebug_blocked_sigs); 568 sigaddset(&unblocked_sigs, SIGILL); 569 sigaddset(&unblocked_sigs, SIGSEGV); 570 sigaddset(&unblocked_sigs, SIGBUS); 571 sigaddset(&unblocked_sigs, SIGFPE); 572 sigaddset(&unblocked_sigs, SR_signum); 573 574 if (!ReduceSignalUsage) { 575 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 576 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 577 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 578 } 579 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 580 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 581 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 582 } 583 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 584 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 585 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 586 } 587 } 588 // Fill in signals that are blocked by all but the VM thread. 589 sigemptyset(&vm_sigs); 590 if (!ReduceSignalUsage) { 591 sigaddset(&vm_sigs, BREAK_SIGNAL); 592 } 593 debug_only(signal_sets_initialized = true); 594 595 } 596 597 // These are signals that are unblocked while a thread is running Java. 598 // (For some reason, they get blocked by default.) 599 sigset_t* os::Bsd::unblocked_signals() { 600 assert(signal_sets_initialized, "Not initialized"); 601 return &unblocked_sigs; 602 } 603 604 // These are the signals that are blocked while a (non-VM) thread is 605 // running Java. Only the VM thread handles these signals. 606 sigset_t* os::Bsd::vm_signals() { 607 assert(signal_sets_initialized, "Not initialized"); 608 return &vm_sigs; 609 } 610 611 // These are signals that are blocked during cond_wait to allow debugger in 612 sigset_t* os::Bsd::allowdebug_blocked_signals() { 613 assert(signal_sets_initialized, "Not initialized"); 614 return &allowdebug_blocked_sigs; 615 } 616 617 void os::Bsd::hotspot_sigmask(Thread* thread) { 618 619 //Save caller's signal mask before setting VM signal mask 620 sigset_t caller_sigmask; 621 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 622 623 OSThread* osthread = thread->osthread(); 624 osthread->set_caller_sigmask(caller_sigmask); 625 626 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 627 628 if (!ReduceSignalUsage) { 629 if (thread->is_VM_thread()) { 630 // Only the VM thread handles BREAK_SIGNAL ... 631 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 632 } else { 633 // ... all other threads block BREAK_SIGNAL 634 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 635 } 636 } 637 } 638 639 640 ////////////////////////////////////////////////////////////////////////////// 641 // create new thread 642 643 #ifdef __APPLE__ 644 // library handle for calling objc_registerThreadWithCollector() 645 // without static linking to the libobjc library 646 #define OBJC_LIB "/usr/lib/libobjc.dylib" 647 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 648 typedef void (*objc_registerThreadWithCollector_t)(); 649 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 650 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 651 #endif 652 653 #ifdef __APPLE__ 654 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 655 // Additional thread_id used to correlate threads in SA 656 thread_identifier_info_data_t m_ident_info; 657 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 658 659 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 660 (thread_info_t) &m_ident_info, &count); 661 662 return m_ident_info.thread_id; 663 } 664 #endif 665 666 // Thread start routine for all newly created threads 667 static void *java_start(Thread *thread) { 668 // Try to randomize the cache line index of hot stack frames. 669 // This helps when threads of the same stack traces evict each other's 670 // cache lines. The threads can be either from the same JVM instance, or 671 // from different JVM instances. The benefit is especially true for 672 // processors with hyperthreading technology. 673 static int counter = 0; 674 int pid = os::current_process_id(); 675 alloca(((pid ^ counter++) & 7) * 128); 676 677 thread->initialize_thread_current(); 678 679 OSThread* osthread = thread->osthread(); 680 Monitor* sync = osthread->startThread_lock(); 681 682 osthread->set_thread_id(os::Bsd::gettid()); 683 684 #ifdef __APPLE__ 685 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 686 guarantee(unique_thread_id != 0, "unique thread id was not found"); 687 osthread->set_unique_thread_id(unique_thread_id); 688 #endif 689 // initialize signal mask for this thread 690 os::Bsd::hotspot_sigmask(thread); 691 692 // initialize floating point control register 693 os::Bsd::init_thread_fpu_state(); 694 695 #ifdef __APPLE__ 696 // register thread with objc gc 697 if (objc_registerThreadWithCollectorFunction != NULL) { 698 objc_registerThreadWithCollectorFunction(); 699 } 700 #endif 701 702 // handshaking with parent thread 703 { 704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 705 706 // notify parent thread 707 osthread->set_state(INITIALIZED); 708 sync->notify_all(); 709 710 // wait until os::start_thread() 711 while (osthread->get_state() == INITIALIZED) { 712 sync->wait(Mutex::_no_safepoint_check_flag); 713 } 714 } 715 716 // call one more level start routine 717 thread->run(); 718 719 return 0; 720 } 721 722 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 723 assert(thread->osthread() == NULL, "caller responsible"); 724 725 // Allocate the OSThread object 726 OSThread* osthread = new OSThread(NULL, NULL); 727 if (osthread == NULL) { 728 return false; 729 } 730 731 // set the correct thread state 732 osthread->set_thread_type(thr_type); 733 734 // Initial state is ALLOCATED but not INITIALIZED 735 osthread->set_state(ALLOCATED); 736 737 thread->set_osthread(osthread); 738 739 // init thread attributes 740 pthread_attr_t attr; 741 pthread_attr_init(&attr); 742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 743 744 // calculate stack size if it's not specified by caller 745 if (stack_size == 0) { 746 stack_size = os::Bsd::default_stack_size(thr_type); 747 748 switch (thr_type) { 749 case os::java_thread: 750 // Java threads use ThreadStackSize which default value can be 751 // changed with the flag -Xss 752 assert(JavaThread::stack_size_at_create() > 0, "this should be set"); 753 stack_size = JavaThread::stack_size_at_create(); 754 break; 755 case os::compiler_thread: 756 if (CompilerThreadStackSize > 0) { 757 stack_size = (size_t)(CompilerThreadStackSize * K); 758 break; 759 } // else fall through: 760 // use VMThreadStackSize if CompilerThreadStackSize is not defined 761 case os::vm_thread: 762 case os::pgc_thread: 763 case os::cgc_thread: 764 case os::watcher_thread: 765 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 766 break; 767 } 768 } 769 770 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 771 pthread_attr_setstacksize(&attr, stack_size); 772 773 ThreadState state; 774 775 { 776 pthread_t tid; 777 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 778 779 pthread_attr_destroy(&attr); 780 781 if (ret != 0) { 782 if (PrintMiscellaneous && (Verbose || WizardMode)) { 783 perror("pthread_create()"); 784 } 785 // Need to clean up stuff we've allocated so far 786 thread->set_osthread(NULL); 787 delete osthread; 788 return false; 789 } 790 791 // Store pthread info into the OSThread 792 osthread->set_pthread_id(tid); 793 794 // Wait until child thread is either initialized or aborted 795 { 796 Monitor* sync_with_child = osthread->startThread_lock(); 797 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 798 while ((state = osthread->get_state()) == ALLOCATED) { 799 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 800 } 801 } 802 803 } 804 805 // Aborted due to thread limit being reached 806 if (state == ZOMBIE) { 807 thread->set_osthread(NULL); 808 delete osthread; 809 return false; 810 } 811 812 // The thread is returned suspended (in state INITIALIZED), 813 // and is started higher up in the call chain 814 assert(state == INITIALIZED, "race condition"); 815 return true; 816 } 817 818 ///////////////////////////////////////////////////////////////////////////// 819 // attach existing thread 820 821 // bootstrap the main thread 822 bool os::create_main_thread(JavaThread* thread) { 823 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 824 return create_attached_thread(thread); 825 } 826 827 bool os::create_attached_thread(JavaThread* thread) { 828 #ifdef ASSERT 829 thread->verify_not_published(); 830 #endif 831 832 // Allocate the OSThread object 833 OSThread* osthread = new OSThread(NULL, NULL); 834 835 if (osthread == NULL) { 836 return false; 837 } 838 839 osthread->set_thread_id(os::Bsd::gettid()); 840 841 // Store pthread info into the OSThread 842 #ifdef __APPLE__ 843 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 844 guarantee(unique_thread_id != 0, "just checking"); 845 osthread->set_unique_thread_id(unique_thread_id); 846 #endif 847 osthread->set_pthread_id(::pthread_self()); 848 849 // initialize floating point control register 850 os::Bsd::init_thread_fpu_state(); 851 852 // Initial thread state is RUNNABLE 853 osthread->set_state(RUNNABLE); 854 855 thread->set_osthread(osthread); 856 857 // initialize signal mask for this thread 858 // and save the caller's signal mask 859 os::Bsd::hotspot_sigmask(thread); 860 861 return true; 862 } 863 864 void os::pd_start_thread(Thread* thread) { 865 OSThread * osthread = thread->osthread(); 866 assert(osthread->get_state() != INITIALIZED, "just checking"); 867 Monitor* sync_with_child = osthread->startThread_lock(); 868 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 869 sync_with_child->notify(); 870 } 871 872 // Free Bsd resources related to the OSThread 873 void os::free_thread(OSThread* osthread) { 874 assert(osthread != NULL, "osthread not set"); 875 876 if (Thread::current()->osthread() == osthread) { 877 // Restore caller's signal mask 878 sigset_t sigmask = osthread->caller_sigmask(); 879 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 880 } 881 882 delete osthread; 883 } 884 885 //////////////////////////////////////////////////////////////////////////////// 886 // time support 887 888 // Time since start-up in seconds to a fine granularity. 889 // Used by VMSelfDestructTimer and the MemProfiler. 890 double os::elapsedTime() { 891 892 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 893 } 894 895 jlong os::elapsed_counter() { 896 return javaTimeNanos() - initial_time_count; 897 } 898 899 jlong os::elapsed_frequency() { 900 return NANOSECS_PER_SEC; // nanosecond resolution 901 } 902 903 bool os::supports_vtime() { return true; } 904 bool os::enable_vtime() { return false; } 905 bool os::vtime_enabled() { return false; } 906 907 double os::elapsedVTime() { 908 // better than nothing, but not much 909 return elapsedTime(); 910 } 911 912 jlong os::javaTimeMillis() { 913 timeval time; 914 int status = gettimeofday(&time, NULL); 915 assert(status != -1, "bsd error"); 916 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 917 } 918 919 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 920 timeval time; 921 int status = gettimeofday(&time, NULL); 922 assert(status != -1, "bsd error"); 923 seconds = jlong(time.tv_sec); 924 nanos = jlong(time.tv_usec) * 1000; 925 } 926 927 #ifndef __APPLE__ 928 #ifndef CLOCK_MONOTONIC 929 #define CLOCK_MONOTONIC (1) 930 #endif 931 #endif 932 933 #ifdef __APPLE__ 934 void os::Bsd::clock_init() { 935 mach_timebase_info(&_timebase_info); 936 } 937 #else 938 void os::Bsd::clock_init() { 939 struct timespec res; 940 struct timespec tp; 941 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 942 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 943 // yes, monotonic clock is supported 944 _clock_gettime = ::clock_gettime; 945 } 946 } 947 #endif 948 949 950 951 #ifdef __APPLE__ 952 953 jlong os::javaTimeNanos() { 954 const uint64_t tm = mach_absolute_time(); 955 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 956 const uint64_t prev = Bsd::_max_abstime; 957 if (now <= prev) { 958 return prev; // same or retrograde time; 959 } 960 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 961 assert(obsv >= prev, "invariant"); // Monotonicity 962 // If the CAS succeeded then we're done and return "now". 963 // If the CAS failed and the observed value "obsv" is >= now then 964 // we should return "obsv". If the CAS failed and now > obsv > prv then 965 // some other thread raced this thread and installed a new value, in which case 966 // we could either (a) retry the entire operation, (b) retry trying to install now 967 // or (c) just return obsv. We use (c). No loop is required although in some cases 968 // we might discard a higher "now" value in deference to a slightly lower but freshly 969 // installed obsv value. That's entirely benign -- it admits no new orderings compared 970 // to (a) or (b) -- and greatly reduces coherence traffic. 971 // We might also condition (c) on the magnitude of the delta between obsv and now. 972 // Avoiding excessive CAS operations to hot RW locations is critical. 973 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 974 return (prev == obsv) ? now : obsv; 975 } 976 977 #else // __APPLE__ 978 979 jlong os::javaTimeNanos() { 980 if (os::supports_monotonic_clock()) { 981 struct timespec tp; 982 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 983 assert(status == 0, "gettime error"); 984 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 985 return result; 986 } else { 987 timeval time; 988 int status = gettimeofday(&time, NULL); 989 assert(status != -1, "bsd error"); 990 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 991 return 1000 * usecs; 992 } 993 } 994 995 #endif // __APPLE__ 996 997 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 998 if (os::supports_monotonic_clock()) { 999 info_ptr->max_value = ALL_64_BITS; 1000 1001 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1002 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1003 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1004 } else { 1005 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1006 info_ptr->max_value = ALL_64_BITS; 1007 1008 // gettimeofday is a real time clock so it skips 1009 info_ptr->may_skip_backward = true; 1010 info_ptr->may_skip_forward = true; 1011 } 1012 1013 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1014 } 1015 1016 // Return the real, user, and system times in seconds from an 1017 // arbitrary fixed point in the past. 1018 bool os::getTimesSecs(double* process_real_time, 1019 double* process_user_time, 1020 double* process_system_time) { 1021 struct tms ticks; 1022 clock_t real_ticks = times(&ticks); 1023 1024 if (real_ticks == (clock_t) (-1)) { 1025 return false; 1026 } else { 1027 double ticks_per_second = (double) clock_tics_per_sec; 1028 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1029 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1030 *process_real_time = ((double) real_ticks) / ticks_per_second; 1031 1032 return true; 1033 } 1034 } 1035 1036 1037 char * os::local_time_string(char *buf, size_t buflen) { 1038 struct tm t; 1039 time_t long_time; 1040 time(&long_time); 1041 localtime_r(&long_time, &t); 1042 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1043 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1044 t.tm_hour, t.tm_min, t.tm_sec); 1045 return buf; 1046 } 1047 1048 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1049 return localtime_r(clock, res); 1050 } 1051 1052 //////////////////////////////////////////////////////////////////////////////// 1053 // runtime exit support 1054 1055 // Note: os::shutdown() might be called very early during initialization, or 1056 // called from signal handler. Before adding something to os::shutdown(), make 1057 // sure it is async-safe and can handle partially initialized VM. 1058 void os::shutdown() { 1059 1060 // allow PerfMemory to attempt cleanup of any persistent resources 1061 perfMemory_exit(); 1062 1063 // needs to remove object in file system 1064 AttachListener::abort(); 1065 1066 // flush buffered output, finish log files 1067 ostream_abort(); 1068 1069 // Check for abort hook 1070 abort_hook_t abort_hook = Arguments::abort_hook(); 1071 if (abort_hook != NULL) { 1072 abort_hook(); 1073 } 1074 1075 } 1076 1077 // Note: os::abort() might be called very early during initialization, or 1078 // called from signal handler. Before adding something to os::abort(), make 1079 // sure it is async-safe and can handle partially initialized VM. 1080 void os::abort(bool dump_core, void* siginfo, void* context) { 1081 os::shutdown(); 1082 if (dump_core) { 1083 #ifndef PRODUCT 1084 fdStream out(defaultStream::output_fd()); 1085 out.print_raw("Current thread is "); 1086 char buf[16]; 1087 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1088 out.print_raw_cr(buf); 1089 out.print_raw_cr("Dumping core ..."); 1090 #endif 1091 ::abort(); // dump core 1092 } 1093 1094 ::exit(1); 1095 } 1096 1097 // Die immediately, no exit hook, no abort hook, no cleanup. 1098 void os::die() { 1099 // _exit() on BsdThreads only kills current thread 1100 ::abort(); 1101 } 1102 1103 // This method is a copy of JDK's sysGetLastErrorString 1104 // from src/solaris/hpi/src/system_md.c 1105 1106 size_t os::lasterror(char *buf, size_t len) { 1107 if (errno == 0) return 0; 1108 1109 const char *s = ::strerror(errno); 1110 size_t n = ::strlen(s); 1111 if (n >= len) { 1112 n = len - 1; 1113 } 1114 ::strncpy(buf, s, n); 1115 buf[n] = '\0'; 1116 return n; 1117 } 1118 1119 // Information of current thread in variety of formats 1120 pid_t os::Bsd::gettid() { 1121 int retval = -1; 1122 1123 #ifdef __APPLE__ //XNU kernel 1124 // despite the fact mach port is actually not a thread id use it 1125 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1126 retval = ::pthread_mach_thread_np(::pthread_self()); 1127 guarantee(retval != 0, "just checking"); 1128 return retval; 1129 1130 #else 1131 #ifdef __FreeBSD__ 1132 retval = syscall(SYS_thr_self); 1133 #else 1134 #ifdef __OpenBSD__ 1135 retval = syscall(SYS_getthrid); 1136 #else 1137 #ifdef __NetBSD__ 1138 retval = (pid_t) syscall(SYS__lwp_self); 1139 #endif 1140 #endif 1141 #endif 1142 #endif 1143 1144 if (retval == -1) { 1145 return getpid(); 1146 } 1147 } 1148 1149 intx os::current_thread_id() { 1150 #ifdef __APPLE__ 1151 return (intx)::pthread_mach_thread_np(::pthread_self()); 1152 #else 1153 return (intx)::pthread_self(); 1154 #endif 1155 } 1156 1157 int os::current_process_id() { 1158 1159 // Under the old bsd thread library, bsd gives each thread 1160 // its own process id. Because of this each thread will return 1161 // a different pid if this method were to return the result 1162 // of getpid(2). Bsd provides no api that returns the pid 1163 // of the launcher thread for the vm. This implementation 1164 // returns a unique pid, the pid of the launcher thread 1165 // that starts the vm 'process'. 1166 1167 // Under the NPTL, getpid() returns the same pid as the 1168 // launcher thread rather than a unique pid per thread. 1169 // Use gettid() if you want the old pre NPTL behaviour. 1170 1171 // if you are looking for the result of a call to getpid() that 1172 // returns a unique pid for the calling thread, then look at the 1173 // OSThread::thread_id() method in osThread_bsd.hpp file 1174 1175 return (int)(_initial_pid ? _initial_pid : getpid()); 1176 } 1177 1178 // DLL functions 1179 1180 #define JNI_LIB_PREFIX "lib" 1181 #ifdef __APPLE__ 1182 #define JNI_LIB_SUFFIX ".dylib" 1183 #else 1184 #define JNI_LIB_SUFFIX ".so" 1185 #endif 1186 1187 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1188 1189 // This must be hard coded because it's the system's temporary 1190 // directory not the java application's temp directory, ala java.io.tmpdir. 1191 #ifdef __APPLE__ 1192 // macosx has a secure per-user temporary directory 1193 char temp_path_storage[PATH_MAX]; 1194 const char* os::get_temp_directory() { 1195 static char *temp_path = NULL; 1196 if (temp_path == NULL) { 1197 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1198 if (pathSize == 0 || pathSize > PATH_MAX) { 1199 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1200 } 1201 temp_path = temp_path_storage; 1202 } 1203 return temp_path; 1204 } 1205 #else // __APPLE__ 1206 const char* os::get_temp_directory() { return "/tmp"; } 1207 #endif // __APPLE__ 1208 1209 static bool file_exists(const char* filename) { 1210 struct stat statbuf; 1211 if (filename == NULL || strlen(filename) == 0) { 1212 return false; 1213 } 1214 return os::stat(filename, &statbuf) == 0; 1215 } 1216 1217 bool os::dll_build_name(char* buffer, size_t buflen, 1218 const char* pname, const char* fname) { 1219 bool retval = false; 1220 // Copied from libhpi 1221 const size_t pnamelen = pname ? strlen(pname) : 0; 1222 1223 // Return error on buffer overflow. 1224 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1225 return retval; 1226 } 1227 1228 if (pnamelen == 0) { 1229 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1230 retval = true; 1231 } else if (strchr(pname, *os::path_separator()) != NULL) { 1232 int n; 1233 char** pelements = split_path(pname, &n); 1234 if (pelements == NULL) { 1235 return false; 1236 } 1237 for (int i = 0; i < n; i++) { 1238 // Really shouldn't be NULL, but check can't hurt 1239 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1240 continue; // skip the empty path values 1241 } 1242 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1243 pelements[i], fname); 1244 if (file_exists(buffer)) { 1245 retval = true; 1246 break; 1247 } 1248 } 1249 // release the storage 1250 for (int i = 0; i < n; i++) { 1251 if (pelements[i] != NULL) { 1252 FREE_C_HEAP_ARRAY(char, pelements[i]); 1253 } 1254 } 1255 if (pelements != NULL) { 1256 FREE_C_HEAP_ARRAY(char*, pelements); 1257 } 1258 } else { 1259 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1260 retval = true; 1261 } 1262 return retval; 1263 } 1264 1265 // check if addr is inside libjvm.so 1266 bool os::address_is_in_vm(address addr) { 1267 static address libjvm_base_addr; 1268 Dl_info dlinfo; 1269 1270 if (libjvm_base_addr == NULL) { 1271 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1272 libjvm_base_addr = (address)dlinfo.dli_fbase; 1273 } 1274 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1275 } 1276 1277 if (dladdr((void *)addr, &dlinfo) != 0) { 1278 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1279 } 1280 1281 return false; 1282 } 1283 1284 1285 #define MACH_MAXSYMLEN 256 1286 1287 bool os::dll_address_to_function_name(address addr, char *buf, 1288 int buflen, int *offset, 1289 bool demangle) { 1290 // buf is not optional, but offset is optional 1291 assert(buf != NULL, "sanity check"); 1292 1293 Dl_info dlinfo; 1294 char localbuf[MACH_MAXSYMLEN]; 1295 1296 if (dladdr((void*)addr, &dlinfo) != 0) { 1297 // see if we have a matching symbol 1298 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1299 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) { 1300 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1301 } 1302 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1303 return true; 1304 } 1305 // no matching symbol so try for just file info 1306 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1307 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1308 buf, buflen, offset, dlinfo.dli_fname, demangle)) { 1309 return true; 1310 } 1311 } 1312 1313 // Handle non-dynamic manually: 1314 if (dlinfo.dli_fbase != NULL && 1315 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1316 dlinfo.dli_fbase)) { 1317 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) { 1318 jio_snprintf(buf, buflen, "%s", localbuf); 1319 } 1320 return true; 1321 } 1322 } 1323 buf[0] = '\0'; 1324 if (offset != NULL) *offset = -1; 1325 return false; 1326 } 1327 1328 // ported from solaris version 1329 bool os::dll_address_to_library_name(address addr, char* buf, 1330 int buflen, int* offset) { 1331 // buf is not optional, but offset is optional 1332 assert(buf != NULL, "sanity check"); 1333 1334 Dl_info dlinfo; 1335 1336 if (dladdr((void*)addr, &dlinfo) != 0) { 1337 if (dlinfo.dli_fname != NULL) { 1338 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1339 } 1340 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1341 *offset = addr - (address)dlinfo.dli_fbase; 1342 } 1343 return true; 1344 } 1345 1346 buf[0] = '\0'; 1347 if (offset) *offset = -1; 1348 return false; 1349 } 1350 1351 // Loads .dll/.so and 1352 // in case of error it checks if .dll/.so was built for the 1353 // same architecture as Hotspot is running on 1354 1355 #ifdef __APPLE__ 1356 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1357 #ifdef STATIC_BUILD 1358 return os::get_default_process_handle(); 1359 #else 1360 void * result= ::dlopen(filename, RTLD_LAZY); 1361 if (result != NULL) { 1362 // Successful loading 1363 return result; 1364 } 1365 1366 // Read system error message into ebuf 1367 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1368 ebuf[ebuflen-1]='\0'; 1369 1370 return NULL; 1371 #endif // STATIC_BUILD 1372 } 1373 #else 1374 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1375 #ifdef STATIC_BUILD 1376 return os::get_default_process_handle(); 1377 #else 1378 void * result= ::dlopen(filename, RTLD_LAZY); 1379 if (result != NULL) { 1380 // Successful loading 1381 return result; 1382 } 1383 1384 Elf32_Ehdr elf_head; 1385 1386 // Read system error message into ebuf 1387 // It may or may not be overwritten below 1388 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1389 ebuf[ebuflen-1]='\0'; 1390 int diag_msg_max_length=ebuflen-strlen(ebuf); 1391 char* diag_msg_buf=ebuf+strlen(ebuf); 1392 1393 if (diag_msg_max_length==0) { 1394 // No more space in ebuf for additional diagnostics message 1395 return NULL; 1396 } 1397 1398 1399 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1400 1401 if (file_descriptor < 0) { 1402 // Can't open library, report dlerror() message 1403 return NULL; 1404 } 1405 1406 bool failed_to_read_elf_head= 1407 (sizeof(elf_head)!= 1408 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1409 1410 ::close(file_descriptor); 1411 if (failed_to_read_elf_head) { 1412 // file i/o error - report dlerror() msg 1413 return NULL; 1414 } 1415 1416 typedef struct { 1417 Elf32_Half code; // Actual value as defined in elf.h 1418 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1419 char elf_class; // 32 or 64 bit 1420 char endianess; // MSB or LSB 1421 char* name; // String representation 1422 } arch_t; 1423 1424 #ifndef EM_486 1425 #define EM_486 6 /* Intel 80486 */ 1426 #endif 1427 1428 #ifndef EM_MIPS_RS3_LE 1429 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1430 #endif 1431 1432 #ifndef EM_PPC64 1433 #define EM_PPC64 21 /* PowerPC64 */ 1434 #endif 1435 1436 #ifndef EM_S390 1437 #define EM_S390 22 /* IBM System/390 */ 1438 #endif 1439 1440 #ifndef EM_IA_64 1441 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1442 #endif 1443 1444 #ifndef EM_X86_64 1445 #define EM_X86_64 62 /* AMD x86-64 */ 1446 #endif 1447 1448 static const arch_t arch_array[]={ 1449 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1450 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1451 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1452 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1453 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1454 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1455 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1456 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1457 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1458 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1459 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1460 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1461 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1462 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1463 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1464 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1465 }; 1466 1467 #if (defined IA32) 1468 static Elf32_Half running_arch_code=EM_386; 1469 #elif (defined AMD64) 1470 static Elf32_Half running_arch_code=EM_X86_64; 1471 #elif (defined IA64) 1472 static Elf32_Half running_arch_code=EM_IA_64; 1473 #elif (defined __sparc) && (defined _LP64) 1474 static Elf32_Half running_arch_code=EM_SPARCV9; 1475 #elif (defined __sparc) && (!defined _LP64) 1476 static Elf32_Half running_arch_code=EM_SPARC; 1477 #elif (defined __powerpc64__) 1478 static Elf32_Half running_arch_code=EM_PPC64; 1479 #elif (defined __powerpc__) 1480 static Elf32_Half running_arch_code=EM_PPC; 1481 #elif (defined ARM) 1482 static Elf32_Half running_arch_code=EM_ARM; 1483 #elif (defined S390) 1484 static Elf32_Half running_arch_code=EM_S390; 1485 #elif (defined ALPHA) 1486 static Elf32_Half running_arch_code=EM_ALPHA; 1487 #elif (defined MIPSEL) 1488 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1489 #elif (defined PARISC) 1490 static Elf32_Half running_arch_code=EM_PARISC; 1491 #elif (defined MIPS) 1492 static Elf32_Half running_arch_code=EM_MIPS; 1493 #elif (defined M68K) 1494 static Elf32_Half running_arch_code=EM_68K; 1495 #else 1496 #error Method os::dll_load requires that one of following is defined:\ 1497 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1498 #endif 1499 1500 // Identify compatability class for VM's architecture and library's architecture 1501 // Obtain string descriptions for architectures 1502 1503 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1504 int running_arch_index=-1; 1505 1506 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1507 if (running_arch_code == arch_array[i].code) { 1508 running_arch_index = i; 1509 } 1510 if (lib_arch.code == arch_array[i].code) { 1511 lib_arch.compat_class = arch_array[i].compat_class; 1512 lib_arch.name = arch_array[i].name; 1513 } 1514 } 1515 1516 assert(running_arch_index != -1, 1517 "Didn't find running architecture code (running_arch_code) in arch_array"); 1518 if (running_arch_index == -1) { 1519 // Even though running architecture detection failed 1520 // we may still continue with reporting dlerror() message 1521 return NULL; 1522 } 1523 1524 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1525 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1526 return NULL; 1527 } 1528 1529 #ifndef S390 1530 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1531 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1532 return NULL; 1533 } 1534 #endif // !S390 1535 1536 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1537 if (lib_arch.name!=NULL) { 1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1539 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1540 lib_arch.name, arch_array[running_arch_index].name); 1541 } else { 1542 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1543 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1544 lib_arch.code, 1545 arch_array[running_arch_index].name); 1546 } 1547 } 1548 1549 return NULL; 1550 #endif // STATIC_BUILD 1551 } 1552 #endif // !__APPLE__ 1553 1554 void* os::get_default_process_handle() { 1555 #ifdef __APPLE__ 1556 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1557 // to avoid finding unexpected symbols on second (or later) 1558 // loads of a library. 1559 return (void*)::dlopen(NULL, RTLD_FIRST); 1560 #else 1561 return (void*)::dlopen(NULL, RTLD_LAZY); 1562 #endif 1563 } 1564 1565 // XXX: Do we need a lock around this as per Linux? 1566 void* os::dll_lookup(void* handle, const char* name) { 1567 return dlsym(handle, name); 1568 } 1569 1570 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1571 outputStream * out = (outputStream *) param; 1572 out->print_cr(PTR_FORMAT " \t%s", base_address, name); 1573 return 0; 1574 } 1575 1576 void os::print_dll_info(outputStream *st) { 1577 st->print_cr("Dynamic libraries:"); 1578 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1579 st->print_cr("Error: Cannot print dynamic libraries."); 1580 } 1581 } 1582 1583 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1584 #ifdef RTLD_DI_LINKMAP 1585 Dl_info dli; 1586 void *handle; 1587 Link_map *map; 1588 Link_map *p; 1589 1590 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1591 dli.dli_fname == NULL) { 1592 return 1; 1593 } 1594 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1595 if (handle == NULL) { 1596 return 1; 1597 } 1598 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1599 if (map == NULL) { 1600 dlclose(handle); 1601 return 1; 1602 } 1603 1604 while (map->l_prev != NULL) 1605 map = map->l_prev; 1606 1607 while (map != NULL) { 1608 // Value for top_address is returned as 0 since we don't have any information about module size 1609 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1610 dlclose(handle); 1611 return 1; 1612 } 1613 map = map->l_next; 1614 } 1615 1616 dlclose(handle); 1617 #elif defined(__APPLE__) 1618 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1619 // Value for top_address is returned as 0 since we don't have any information about module size 1620 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1621 return 1; 1622 } 1623 } 1624 return 0; 1625 #else 1626 return 1; 1627 #endif 1628 } 1629 1630 void os::get_summary_os_info(char* buf, size_t buflen) { 1631 // These buffers are small because we want this to be brief 1632 // and not use a lot of stack while generating the hs_err file. 1633 char os[100]; 1634 size_t size = sizeof(os); 1635 int mib_kern[] = { CTL_KERN, KERN_OSTYPE }; 1636 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) { 1637 #ifdef __APPLE__ 1638 strncpy(os, "Darwin", sizeof(os)); 1639 #elif __OpenBSD__ 1640 strncpy(os, "OpenBSD", sizeof(os)); 1641 #else 1642 strncpy(os, "BSD", sizeof(os)); 1643 #endif 1644 } 1645 1646 char release[100]; 1647 size = sizeof(release); 1648 int mib_release[] = { CTL_KERN, KERN_OSRELEASE }; 1649 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) { 1650 // if error, leave blank 1651 strncpy(release, "", sizeof(release)); 1652 } 1653 snprintf(buf, buflen, "%s %s", os, release); 1654 } 1655 1656 void os::print_os_info_brief(outputStream* st) { 1657 os::Posix::print_uname_info(st); 1658 } 1659 1660 void os::print_os_info(outputStream* st) { 1661 st->print("OS:"); 1662 1663 os::Posix::print_uname_info(st); 1664 1665 os::Posix::print_rlimit_info(st); 1666 1667 os::Posix::print_load_average(st); 1668 } 1669 1670 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) { 1671 // Nothing to do for now. 1672 } 1673 1674 void os::get_summary_cpu_info(char* buf, size_t buflen) { 1675 unsigned int mhz; 1676 size_t size = sizeof(mhz); 1677 int mib[] = { CTL_HW, HW_CPU_FREQ }; 1678 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) { 1679 mhz = 1; // looks like an error but can be divided by 1680 } else { 1681 mhz /= 1000000; // reported in millions 1682 } 1683 1684 char model[100]; 1685 size = sizeof(model); 1686 int mib_model[] = { CTL_HW, HW_MODEL }; 1687 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) { 1688 strncpy(model, cpu_arch, sizeof(model)); 1689 } 1690 1691 char machine[100]; 1692 size = sizeof(machine); 1693 int mib_machine[] = { CTL_HW, HW_MACHINE }; 1694 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) { 1695 strncpy(machine, "", sizeof(machine)); 1696 } 1697 1698 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz); 1699 } 1700 1701 void os::print_memory_info(outputStream* st) { 1702 1703 st->print("Memory:"); 1704 st->print(" %dk page", os::vm_page_size()>>10); 1705 1706 st->print(", physical " UINT64_FORMAT "k", 1707 os::physical_memory() >> 10); 1708 st->print("(" UINT64_FORMAT "k free)", 1709 os::available_memory() >> 10); 1710 st->cr(); 1711 } 1712 1713 void os::print_siginfo(outputStream* st, void* siginfo) { 1714 const siginfo_t* si = (const siginfo_t*)siginfo; 1715 1716 os::Posix::print_siginfo_brief(st, si); 1717 1718 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1719 UseSharedSpaces) { 1720 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1721 if (mapinfo->is_in_shared_space(si->si_addr)) { 1722 st->print("\n\nError accessing class data sharing archive." \ 1723 " Mapped file inaccessible during execution, " \ 1724 " possible disk/network problem."); 1725 } 1726 } 1727 st->cr(); 1728 } 1729 1730 1731 static void print_signal_handler(outputStream* st, int sig, 1732 char* buf, size_t buflen); 1733 1734 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1735 st->print_cr("Signal Handlers:"); 1736 print_signal_handler(st, SIGSEGV, buf, buflen); 1737 print_signal_handler(st, SIGBUS , buf, buflen); 1738 print_signal_handler(st, SIGFPE , buf, buflen); 1739 print_signal_handler(st, SIGPIPE, buf, buflen); 1740 print_signal_handler(st, SIGXFSZ, buf, buflen); 1741 print_signal_handler(st, SIGILL , buf, buflen); 1742 print_signal_handler(st, SR_signum, buf, buflen); 1743 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1744 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1745 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1746 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1747 } 1748 1749 static char saved_jvm_path[MAXPATHLEN] = {0}; 1750 1751 // Find the full path to the current module, libjvm 1752 void os::jvm_path(char *buf, jint buflen) { 1753 // Error checking. 1754 if (buflen < MAXPATHLEN) { 1755 assert(false, "must use a large-enough buffer"); 1756 buf[0] = '\0'; 1757 return; 1758 } 1759 // Lazy resolve the path to current module. 1760 if (saved_jvm_path[0] != 0) { 1761 strcpy(buf, saved_jvm_path); 1762 return; 1763 } 1764 1765 char dli_fname[MAXPATHLEN]; 1766 bool ret = dll_address_to_library_name( 1767 CAST_FROM_FN_PTR(address, os::jvm_path), 1768 dli_fname, sizeof(dli_fname), NULL); 1769 assert(ret, "cannot locate libjvm"); 1770 char *rp = NULL; 1771 if (ret && dli_fname[0] != '\0') { 1772 rp = realpath(dli_fname, buf); 1773 } 1774 if (rp == NULL) { 1775 return; 1776 } 1777 1778 if (Arguments::sun_java_launcher_is_altjvm()) { 1779 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1780 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1781 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1782 // appears at the right place in the string, then assume we are 1783 // installed in a JDK and we're done. Otherwise, check for a 1784 // JAVA_HOME environment variable and construct a path to the JVM 1785 // being overridden. 1786 1787 const char *p = buf + strlen(buf) - 1; 1788 for (int count = 0; p > buf && count < 5; ++count) { 1789 for (--p; p > buf && *p != '/'; --p) 1790 /* empty */ ; 1791 } 1792 1793 if (strncmp(p, "/jre/lib/", 9) != 0) { 1794 // Look for JAVA_HOME in the environment. 1795 char* java_home_var = ::getenv("JAVA_HOME"); 1796 if (java_home_var != NULL && java_home_var[0] != 0) { 1797 char* jrelib_p; 1798 int len; 1799 1800 // Check the current module name "libjvm" 1801 p = strrchr(buf, '/'); 1802 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1803 1804 rp = realpath(java_home_var, buf); 1805 if (rp == NULL) { 1806 return; 1807 } 1808 1809 // determine if this is a legacy image or modules image 1810 // modules image doesn't have "jre" subdirectory 1811 len = strlen(buf); 1812 assert(len < buflen, "Ran out of buffer space"); 1813 jrelib_p = buf + len; 1814 1815 // Add the appropriate library subdir 1816 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1817 if (0 != access(buf, F_OK)) { 1818 snprintf(jrelib_p, buflen-len, "/lib"); 1819 } 1820 1821 // Add the appropriate client or server subdir 1822 len = strlen(buf); 1823 jrelib_p = buf + len; 1824 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1825 if (0 != access(buf, F_OK)) { 1826 snprintf(jrelib_p, buflen-len, "%s", ""); 1827 } 1828 1829 // If the path exists within JAVA_HOME, add the JVM library name 1830 // to complete the path to JVM being overridden. Otherwise fallback 1831 // to the path to the current library. 1832 if (0 == access(buf, F_OK)) { 1833 // Use current module name "libjvm" 1834 len = strlen(buf); 1835 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1836 } else { 1837 // Fall back to path of current library 1838 rp = realpath(dli_fname, buf); 1839 if (rp == NULL) { 1840 return; 1841 } 1842 } 1843 } 1844 } 1845 } 1846 1847 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1848 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1849 } 1850 1851 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1852 // no prefix required, not even "_" 1853 } 1854 1855 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1856 // no suffix required 1857 } 1858 1859 //////////////////////////////////////////////////////////////////////////////// 1860 // sun.misc.Signal support 1861 1862 static volatile jint sigint_count = 0; 1863 1864 static void UserHandler(int sig, void *siginfo, void *context) { 1865 // 4511530 - sem_post is serialized and handled by the manager thread. When 1866 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1867 // don't want to flood the manager thread with sem_post requests. 1868 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1869 return; 1870 } 1871 1872 // Ctrl-C is pressed during error reporting, likely because the error 1873 // handler fails to abort. Let VM die immediately. 1874 if (sig == SIGINT && is_error_reported()) { 1875 os::die(); 1876 } 1877 1878 os::signal_notify(sig); 1879 } 1880 1881 void* os::user_handler() { 1882 return CAST_FROM_FN_PTR(void*, UserHandler); 1883 } 1884 1885 extern "C" { 1886 typedef void (*sa_handler_t)(int); 1887 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1888 } 1889 1890 void* os::signal(int signal_number, void* handler) { 1891 struct sigaction sigAct, oldSigAct; 1892 1893 sigfillset(&(sigAct.sa_mask)); 1894 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1895 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1896 1897 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1898 // -1 means registration failed 1899 return (void *)-1; 1900 } 1901 1902 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1903 } 1904 1905 void os::signal_raise(int signal_number) { 1906 ::raise(signal_number); 1907 } 1908 1909 // The following code is moved from os.cpp for making this 1910 // code platform specific, which it is by its very nature. 1911 1912 // Will be modified when max signal is changed to be dynamic 1913 int os::sigexitnum_pd() { 1914 return NSIG; 1915 } 1916 1917 // a counter for each possible signal value 1918 static volatile jint pending_signals[NSIG+1] = { 0 }; 1919 1920 // Bsd(POSIX) specific hand shaking semaphore. 1921 #ifdef __APPLE__ 1922 typedef semaphore_t os_semaphore_t; 1923 1924 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1925 #define SEM_WAIT(sem) semaphore_wait(sem) 1926 #define SEM_POST(sem) semaphore_signal(sem) 1927 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1928 #else 1929 typedef sem_t os_semaphore_t; 1930 1931 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1932 #define SEM_WAIT(sem) sem_wait(&sem) 1933 #define SEM_POST(sem) sem_post(&sem) 1934 #define SEM_DESTROY(sem) sem_destroy(&sem) 1935 #endif 1936 1937 #ifdef __APPLE__ 1938 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used. 1939 1940 static const char* sem_init_strerror(kern_return_t value) { 1941 switch (value) { 1942 case KERN_INVALID_ARGUMENT: return "Invalid argument"; 1943 case KERN_RESOURCE_SHORTAGE: return "Resource shortage"; 1944 default: return "Unknown"; 1945 } 1946 } 1947 1948 OSXSemaphore::OSXSemaphore(uint value) { 1949 kern_return_t ret = SEM_INIT(_semaphore, value); 1950 1951 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret)); 1952 } 1953 1954 OSXSemaphore::~OSXSemaphore() { 1955 SEM_DESTROY(_semaphore); 1956 } 1957 1958 void OSXSemaphore::signal(uint count) { 1959 for (uint i = 0; i < count; i++) { 1960 kern_return_t ret = SEM_POST(_semaphore); 1961 1962 assert(ret == KERN_SUCCESS, "Failed to signal semaphore"); 1963 } 1964 } 1965 1966 void OSXSemaphore::wait() { 1967 kern_return_t ret; 1968 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) { 1969 // Semaphore was interrupted. Retry. 1970 } 1971 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore"); 1972 } 1973 1974 jlong OSXSemaphore::currenttime() { 1975 struct timeval tv; 1976 gettimeofday(&tv, NULL); 1977 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1978 } 1979 1980 bool OSXSemaphore::trywait() { 1981 return timedwait(0, 0); 1982 } 1983 1984 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) { 1985 kern_return_t kr = KERN_ABORTED; 1986 mach_timespec_t waitspec; 1987 waitspec.tv_sec = sec; 1988 waitspec.tv_nsec = nsec; 1989 1990 jlong starttime = currenttime(); 1991 1992 kr = semaphore_timedwait(_semaphore, waitspec); 1993 while (kr == KERN_ABORTED) { 1994 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1995 1996 jlong current = currenttime(); 1997 jlong passedtime = current - starttime; 1998 1999 if (passedtime >= totalwait) { 2000 waitspec.tv_sec = 0; 2001 waitspec.tv_nsec = 0; 2002 } else { 2003 jlong waittime = totalwait - (current - starttime); 2004 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2005 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2006 } 2007 2008 kr = semaphore_timedwait(_semaphore, waitspec); 2009 } 2010 2011 return kr == KERN_SUCCESS; 2012 } 2013 2014 #else 2015 // Use POSIX implementation of semaphores. 2016 2017 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) { 2018 struct timespec ts; 2019 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2020 2021 return ts; 2022 } 2023 2024 #endif // __APPLE__ 2025 2026 static os_semaphore_t sig_sem; 2027 2028 #ifdef __APPLE__ 2029 static OSXSemaphore sr_semaphore; 2030 #else 2031 static PosixSemaphore sr_semaphore; 2032 #endif 2033 2034 void os::signal_init_pd() { 2035 // Initialize signal structures 2036 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2037 2038 // Initialize signal semaphore 2039 ::SEM_INIT(sig_sem, 0); 2040 } 2041 2042 void os::signal_notify(int sig) { 2043 Atomic::inc(&pending_signals[sig]); 2044 ::SEM_POST(sig_sem); 2045 } 2046 2047 static int check_pending_signals(bool wait) { 2048 Atomic::store(0, &sigint_count); 2049 for (;;) { 2050 for (int i = 0; i < NSIG + 1; i++) { 2051 jint n = pending_signals[i]; 2052 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2053 return i; 2054 } 2055 } 2056 if (!wait) { 2057 return -1; 2058 } 2059 JavaThread *thread = JavaThread::current(); 2060 ThreadBlockInVM tbivm(thread); 2061 2062 bool threadIsSuspended; 2063 do { 2064 thread->set_suspend_equivalent(); 2065 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2066 ::SEM_WAIT(sig_sem); 2067 2068 // were we externally suspended while we were waiting? 2069 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2070 if (threadIsSuspended) { 2071 // The semaphore has been incremented, but while we were waiting 2072 // another thread suspended us. We don't want to continue running 2073 // while suspended because that would surprise the thread that 2074 // suspended us. 2075 ::SEM_POST(sig_sem); 2076 2077 thread->java_suspend_self(); 2078 } 2079 } while (threadIsSuspended); 2080 } 2081 } 2082 2083 int os::signal_lookup() { 2084 return check_pending_signals(false); 2085 } 2086 2087 int os::signal_wait() { 2088 return check_pending_signals(true); 2089 } 2090 2091 //////////////////////////////////////////////////////////////////////////////// 2092 // Virtual Memory 2093 2094 int os::vm_page_size() { 2095 // Seems redundant as all get out 2096 assert(os::Bsd::page_size() != -1, "must call os::init"); 2097 return os::Bsd::page_size(); 2098 } 2099 2100 // Solaris allocates memory by pages. 2101 int os::vm_allocation_granularity() { 2102 assert(os::Bsd::page_size() != -1, "must call os::init"); 2103 return os::Bsd::page_size(); 2104 } 2105 2106 // Rationale behind this function: 2107 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2108 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2109 // samples for JITted code. Here we create private executable mapping over the code cache 2110 // and then we can use standard (well, almost, as mapping can change) way to provide 2111 // info for the reporting script by storing timestamp and location of symbol 2112 void bsd_wrap_code(char* base, size_t size) { 2113 static volatile jint cnt = 0; 2114 2115 if (!UseOprofile) { 2116 return; 2117 } 2118 2119 char buf[PATH_MAX + 1]; 2120 int num = Atomic::add(1, &cnt); 2121 2122 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2123 os::get_temp_directory(), os::current_process_id(), num); 2124 unlink(buf); 2125 2126 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2127 2128 if (fd != -1) { 2129 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2130 if (rv != (off_t)-1) { 2131 if (::write(fd, "", 1) == 1) { 2132 mmap(base, size, 2133 PROT_READ|PROT_WRITE|PROT_EXEC, 2134 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2135 } 2136 } 2137 ::close(fd); 2138 unlink(buf); 2139 } 2140 } 2141 2142 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2143 int err) { 2144 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2145 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2146 strerror(err), err); 2147 } 2148 2149 // NOTE: Bsd kernel does not really reserve the pages for us. 2150 // All it does is to check if there are enough free pages 2151 // left at the time of mmap(). This could be a potential 2152 // problem. 2153 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2154 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2155 #ifdef __OpenBSD__ 2156 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2157 if (::mprotect(addr, size, prot) == 0) { 2158 return true; 2159 } 2160 #else 2161 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2162 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2163 if (res != (uintptr_t) MAP_FAILED) { 2164 return true; 2165 } 2166 #endif 2167 2168 // Warn about any commit errors we see in non-product builds just 2169 // in case mmap() doesn't work as described on the man page. 2170 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2171 2172 return false; 2173 } 2174 2175 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2176 bool exec) { 2177 // alignment_hint is ignored on this OS 2178 return pd_commit_memory(addr, size, exec); 2179 } 2180 2181 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2182 const char* mesg) { 2183 assert(mesg != NULL, "mesg must be specified"); 2184 if (!pd_commit_memory(addr, size, exec)) { 2185 // add extra info in product mode for vm_exit_out_of_memory(): 2186 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2187 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg); 2188 } 2189 } 2190 2191 void os::pd_commit_memory_or_exit(char* addr, size_t size, 2192 size_t alignment_hint, bool exec, 2193 const char* mesg) { 2194 // alignment_hint is ignored on this OS 2195 pd_commit_memory_or_exit(addr, size, exec, mesg); 2196 } 2197 2198 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2199 } 2200 2201 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2202 ::madvise(addr, bytes, MADV_DONTNEED); 2203 } 2204 2205 void os::numa_make_global(char *addr, size_t bytes) { 2206 } 2207 2208 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2209 } 2210 2211 bool os::numa_topology_changed() { return false; } 2212 2213 size_t os::numa_get_groups_num() { 2214 return 1; 2215 } 2216 2217 int os::numa_get_group_id() { 2218 return 0; 2219 } 2220 2221 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2222 if (size > 0) { 2223 ids[0] = 0; 2224 return 1; 2225 } 2226 return 0; 2227 } 2228 2229 bool os::get_page_info(char *start, page_info* info) { 2230 return false; 2231 } 2232 2233 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2234 return end; 2235 } 2236 2237 2238 bool os::pd_uncommit_memory(char* addr, size_t size) { 2239 #ifdef __OpenBSD__ 2240 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2241 return ::mprotect(addr, size, PROT_NONE) == 0; 2242 #else 2243 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2244 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2245 return res != (uintptr_t) MAP_FAILED; 2246 #endif 2247 } 2248 2249 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2250 return os::commit_memory(addr, size, !ExecMem); 2251 } 2252 2253 // If this is a growable mapping, remove the guard pages entirely by 2254 // munmap()ping them. If not, just call uncommit_memory(). 2255 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2256 return os::uncommit_memory(addr, size); 2257 } 2258 2259 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2260 // at 'requested_addr'. If there are existing memory mappings at the same 2261 // location, however, they will be overwritten. If 'fixed' is false, 2262 // 'requested_addr' is only treated as a hint, the return value may or 2263 // may not start from the requested address. Unlike Bsd mmap(), this 2264 // function returns NULL to indicate failure. 2265 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2266 char * addr; 2267 int flags; 2268 2269 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2270 if (fixed) { 2271 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2272 flags |= MAP_FIXED; 2273 } 2274 2275 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2276 // touch an uncommitted page. Otherwise, the read/write might 2277 // succeed if we have enough swap space to back the physical page. 2278 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2279 flags, -1, 0); 2280 2281 return addr == MAP_FAILED ? NULL : addr; 2282 } 2283 2284 static int anon_munmap(char * addr, size_t size) { 2285 return ::munmap(addr, size) == 0; 2286 } 2287 2288 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2289 size_t alignment_hint) { 2290 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2291 } 2292 2293 bool os::pd_release_memory(char* addr, size_t size) { 2294 return anon_munmap(addr, size); 2295 } 2296 2297 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2298 // Bsd wants the mprotect address argument to be page aligned. 2299 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2300 2301 // According to SUSv3, mprotect() should only be used with mappings 2302 // established by mmap(), and mmap() always maps whole pages. Unaligned 2303 // 'addr' likely indicates problem in the VM (e.g. trying to change 2304 // protection of malloc'ed or statically allocated memory). Check the 2305 // caller if you hit this assert. 2306 assert(addr == bottom, "sanity check"); 2307 2308 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2309 return ::mprotect(bottom, size, prot) == 0; 2310 } 2311 2312 // Set protections specified 2313 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2314 bool is_committed) { 2315 unsigned int p = 0; 2316 switch (prot) { 2317 case MEM_PROT_NONE: p = PROT_NONE; break; 2318 case MEM_PROT_READ: p = PROT_READ; break; 2319 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2320 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2321 default: 2322 ShouldNotReachHere(); 2323 } 2324 // is_committed is unused. 2325 return bsd_mprotect(addr, bytes, p); 2326 } 2327 2328 bool os::guard_memory(char* addr, size_t size) { 2329 return bsd_mprotect(addr, size, PROT_NONE); 2330 } 2331 2332 bool os::unguard_memory(char* addr, size_t size) { 2333 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2334 } 2335 2336 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2337 return false; 2338 } 2339 2340 // Large page support 2341 2342 static size_t _large_page_size = 0; 2343 2344 void os::large_page_init() { 2345 } 2346 2347 2348 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2349 fatal("This code is not used or maintained."); 2350 2351 // "exec" is passed in but not used. Creating the shared image for 2352 // the code cache doesn't have an SHM_X executable permission to check. 2353 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2354 2355 key_t key = IPC_PRIVATE; 2356 char *addr; 2357 2358 bool warn_on_failure = UseLargePages && 2359 (!FLAG_IS_DEFAULT(UseLargePages) || 2360 !FLAG_IS_DEFAULT(LargePageSizeInBytes)); 2361 2362 // Create a large shared memory region to attach to based on size. 2363 // Currently, size is the total size of the heap 2364 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2365 if (shmid == -1) { 2366 // Possible reasons for shmget failure: 2367 // 1. shmmax is too small for Java heap. 2368 // > check shmmax value: cat /proc/sys/kernel/shmmax 2369 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2370 // 2. not enough large page memory. 2371 // > check available large pages: cat /proc/meminfo 2372 // > increase amount of large pages: 2373 // echo new_value > /proc/sys/vm/nr_hugepages 2374 // Note 1: different Bsd may use different name for this property, 2375 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2376 // Note 2: it's possible there's enough physical memory available but 2377 // they are so fragmented after a long run that they can't 2378 // coalesce into large pages. Try to reserve large pages when 2379 // the system is still "fresh". 2380 if (warn_on_failure) { 2381 warning("Failed to reserve shared memory (errno = %d).", errno); 2382 } 2383 return NULL; 2384 } 2385 2386 // attach to the region 2387 addr = (char*)shmat(shmid, req_addr, 0); 2388 int err = errno; 2389 2390 // Remove shmid. If shmat() is successful, the actual shared memory segment 2391 // will be deleted when it's detached by shmdt() or when the process 2392 // terminates. If shmat() is not successful this will remove the shared 2393 // segment immediately. 2394 shmctl(shmid, IPC_RMID, NULL); 2395 2396 if ((intptr_t)addr == -1) { 2397 if (warn_on_failure) { 2398 warning("Failed to attach shared memory (errno = %d).", err); 2399 } 2400 return NULL; 2401 } 2402 2403 // The memory is committed 2404 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2405 2406 return addr; 2407 } 2408 2409 bool os::release_memory_special(char* base, size_t bytes) { 2410 if (MemTracker::tracking_level() > NMT_minimal) { 2411 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2412 // detaching the SHM segment will also delete it, see reserve_memory_special() 2413 int rslt = shmdt(base); 2414 if (rslt == 0) { 2415 tkr.record((address)base, bytes); 2416 return true; 2417 } else { 2418 return false; 2419 } 2420 } else { 2421 return shmdt(base) == 0; 2422 } 2423 } 2424 2425 size_t os::large_page_size() { 2426 return _large_page_size; 2427 } 2428 2429 // HugeTLBFS allows application to commit large page memory on demand; 2430 // with SysV SHM the entire memory region must be allocated as shared 2431 // memory. 2432 bool os::can_commit_large_page_memory() { 2433 return UseHugeTLBFS; 2434 } 2435 2436 bool os::can_execute_large_page_memory() { 2437 return UseHugeTLBFS; 2438 } 2439 2440 // Reserve memory at an arbitrary address, only if that area is 2441 // available (and not reserved for something else). 2442 2443 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2444 const int max_tries = 10; 2445 char* base[max_tries]; 2446 size_t size[max_tries]; 2447 const size_t gap = 0x000000; 2448 2449 // Assert only that the size is a multiple of the page size, since 2450 // that's all that mmap requires, and since that's all we really know 2451 // about at this low abstraction level. If we need higher alignment, 2452 // we can either pass an alignment to this method or verify alignment 2453 // in one of the methods further up the call chain. See bug 5044738. 2454 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2455 2456 // Repeatedly allocate blocks until the block is allocated at the 2457 // right spot. 2458 2459 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2460 // if kernel honors the hint then we can return immediately. 2461 char * addr = anon_mmap(requested_addr, bytes, false); 2462 if (addr == requested_addr) { 2463 return requested_addr; 2464 } 2465 2466 if (addr != NULL) { 2467 // mmap() is successful but it fails to reserve at the requested address 2468 anon_munmap(addr, bytes); 2469 } 2470 2471 int i; 2472 for (i = 0; i < max_tries; ++i) { 2473 base[i] = reserve_memory(bytes); 2474 2475 if (base[i] != NULL) { 2476 // Is this the block we wanted? 2477 if (base[i] == requested_addr) { 2478 size[i] = bytes; 2479 break; 2480 } 2481 2482 // Does this overlap the block we wanted? Give back the overlapped 2483 // parts and try again. 2484 2485 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2486 if (top_overlap >= 0 && top_overlap < bytes) { 2487 unmap_memory(base[i], top_overlap); 2488 base[i] += top_overlap; 2489 size[i] = bytes - top_overlap; 2490 } else { 2491 size_t bottom_overlap = base[i] + bytes - requested_addr; 2492 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2493 unmap_memory(requested_addr, bottom_overlap); 2494 size[i] = bytes - bottom_overlap; 2495 } else { 2496 size[i] = bytes; 2497 } 2498 } 2499 } 2500 } 2501 2502 // Give back the unused reserved pieces. 2503 2504 for (int j = 0; j < i; ++j) { 2505 if (base[j] != NULL) { 2506 unmap_memory(base[j], size[j]); 2507 } 2508 } 2509 2510 if (i < max_tries) { 2511 return requested_addr; 2512 } else { 2513 return NULL; 2514 } 2515 } 2516 2517 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2518 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2519 } 2520 2521 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2522 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2523 } 2524 2525 void os::naked_short_sleep(jlong ms) { 2526 struct timespec req; 2527 2528 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2529 req.tv_sec = 0; 2530 if (ms > 0) { 2531 req.tv_nsec = (ms % 1000) * 1000000; 2532 } else { 2533 req.tv_nsec = 1; 2534 } 2535 2536 nanosleep(&req, NULL); 2537 2538 return; 2539 } 2540 2541 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2542 void os::infinite_sleep() { 2543 while (true) { // sleep forever ... 2544 ::sleep(100); // ... 100 seconds at a time 2545 } 2546 } 2547 2548 // Used to convert frequent JVM_Yield() to nops 2549 bool os::dont_yield() { 2550 return DontYieldALot; 2551 } 2552 2553 void os::naked_yield() { 2554 sched_yield(); 2555 } 2556 2557 //////////////////////////////////////////////////////////////////////////////// 2558 // thread priority support 2559 2560 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2561 // only supports dynamic priority, static priority must be zero. For real-time 2562 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2563 // However, for large multi-threaded applications, SCHED_RR is not only slower 2564 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2565 // of 5 runs - Sep 2005). 2566 // 2567 // The following code actually changes the niceness of kernel-thread/LWP. It 2568 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2569 // not the entire user process, and user level threads are 1:1 mapped to kernel 2570 // threads. It has always been the case, but could change in the future. For 2571 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2572 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2573 2574 #if !defined(__APPLE__) 2575 int os::java_to_os_priority[CriticalPriority + 1] = { 2576 19, // 0 Entry should never be used 2577 2578 0, // 1 MinPriority 2579 3, // 2 2580 6, // 3 2581 2582 10, // 4 2583 15, // 5 NormPriority 2584 18, // 6 2585 2586 21, // 7 2587 25, // 8 2588 28, // 9 NearMaxPriority 2589 2590 31, // 10 MaxPriority 2591 2592 31 // 11 CriticalPriority 2593 }; 2594 #else 2595 // Using Mach high-level priority assignments 2596 int os::java_to_os_priority[CriticalPriority + 1] = { 2597 0, // 0 Entry should never be used (MINPRI_USER) 2598 2599 27, // 1 MinPriority 2600 28, // 2 2601 29, // 3 2602 2603 30, // 4 2604 31, // 5 NormPriority (BASEPRI_DEFAULT) 2605 32, // 6 2606 2607 33, // 7 2608 34, // 8 2609 35, // 9 NearMaxPriority 2610 2611 36, // 10 MaxPriority 2612 2613 36 // 11 CriticalPriority 2614 }; 2615 #endif 2616 2617 static int prio_init() { 2618 if (ThreadPriorityPolicy == 1) { 2619 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2620 // if effective uid is not root. Perhaps, a more elegant way of doing 2621 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2622 if (geteuid() != 0) { 2623 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2624 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2625 } 2626 ThreadPriorityPolicy = 0; 2627 } 2628 } 2629 if (UseCriticalJavaThreadPriority) { 2630 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2631 } 2632 return 0; 2633 } 2634 2635 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2636 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2637 2638 #ifdef __OpenBSD__ 2639 // OpenBSD pthread_setprio starves low priority threads 2640 return OS_OK; 2641 #elif defined(__FreeBSD__) 2642 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2643 #elif defined(__APPLE__) || defined(__NetBSD__) 2644 struct sched_param sp; 2645 int policy; 2646 pthread_t self = pthread_self(); 2647 2648 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2649 return OS_ERR; 2650 } 2651 2652 sp.sched_priority = newpri; 2653 if (pthread_setschedparam(self, policy, &sp) != 0) { 2654 return OS_ERR; 2655 } 2656 2657 return OS_OK; 2658 #else 2659 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2660 return (ret == 0) ? OS_OK : OS_ERR; 2661 #endif 2662 } 2663 2664 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2665 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2666 *priority_ptr = java_to_os_priority[NormPriority]; 2667 return OS_OK; 2668 } 2669 2670 errno = 0; 2671 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2672 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2673 #elif defined(__APPLE__) || defined(__NetBSD__) 2674 int policy; 2675 struct sched_param sp; 2676 2677 pthread_getschedparam(pthread_self(), &policy, &sp); 2678 *priority_ptr = sp.sched_priority; 2679 #else 2680 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2681 #endif 2682 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2683 } 2684 2685 // Hint to the underlying OS that a task switch would not be good. 2686 // Void return because it's a hint and can fail. 2687 void os::hint_no_preempt() {} 2688 2689 //////////////////////////////////////////////////////////////////////////////// 2690 // suspend/resume support 2691 2692 // the low-level signal-based suspend/resume support is a remnant from the 2693 // old VM-suspension that used to be for java-suspension, safepoints etc, 2694 // within hotspot. Now there is a single use-case for this: 2695 // - calling get_thread_pc() on the VMThread by the flat-profiler task 2696 // that runs in the watcher thread. 2697 // The remaining code is greatly simplified from the more general suspension 2698 // code that used to be used. 2699 // 2700 // The protocol is quite simple: 2701 // - suspend: 2702 // - sends a signal to the target thread 2703 // - polls the suspend state of the osthread using a yield loop 2704 // - target thread signal handler (SR_handler) sets suspend state 2705 // and blocks in sigsuspend until continued 2706 // - resume: 2707 // - sets target osthread state to continue 2708 // - sends signal to end the sigsuspend loop in the SR_handler 2709 // 2710 // Note that the SR_lock plays no role in this suspend/resume protocol. 2711 2712 static void resume_clear_context(OSThread *osthread) { 2713 osthread->set_ucontext(NULL); 2714 osthread->set_siginfo(NULL); 2715 } 2716 2717 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2718 osthread->set_ucontext(context); 2719 osthread->set_siginfo(siginfo); 2720 } 2721 2722 // Handler function invoked when a thread's execution is suspended or 2723 // resumed. We have to be careful that only async-safe functions are 2724 // called here (Note: most pthread functions are not async safe and 2725 // should be avoided.) 2726 // 2727 // Note: sigwait() is a more natural fit than sigsuspend() from an 2728 // interface point of view, but sigwait() prevents the signal hander 2729 // from being run. libpthread would get very confused by not having 2730 // its signal handlers run and prevents sigwait()'s use with the 2731 // mutex granting granting signal. 2732 // 2733 // Currently only ever called on the VMThread or JavaThread 2734 // 2735 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2736 // Save and restore errno to avoid confusing native code with EINTR 2737 // after sigsuspend. 2738 int old_errno = errno; 2739 2740 Thread* thread = Thread::current(); 2741 OSThread* osthread = thread->osthread(); 2742 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2743 2744 os::SuspendResume::State current = osthread->sr.state(); 2745 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2746 suspend_save_context(osthread, siginfo, context); 2747 2748 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2749 os::SuspendResume::State state = osthread->sr.suspended(); 2750 if (state == os::SuspendResume::SR_SUSPENDED) { 2751 sigset_t suspend_set; // signals for sigsuspend() 2752 2753 // get current set of blocked signals and unblock resume signal 2754 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2755 sigdelset(&suspend_set, SR_signum); 2756 2757 sr_semaphore.signal(); 2758 // wait here until we are resumed 2759 while (1) { 2760 sigsuspend(&suspend_set); 2761 2762 os::SuspendResume::State result = osthread->sr.running(); 2763 if (result == os::SuspendResume::SR_RUNNING) { 2764 sr_semaphore.signal(); 2765 break; 2766 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2767 ShouldNotReachHere(); 2768 } 2769 } 2770 2771 } else if (state == os::SuspendResume::SR_RUNNING) { 2772 // request was cancelled, continue 2773 } else { 2774 ShouldNotReachHere(); 2775 } 2776 2777 resume_clear_context(osthread); 2778 } else if (current == os::SuspendResume::SR_RUNNING) { 2779 // request was cancelled, continue 2780 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2781 // ignore 2782 } else { 2783 // ignore 2784 } 2785 2786 errno = old_errno; 2787 } 2788 2789 2790 static int SR_initialize() { 2791 struct sigaction act; 2792 char *s; 2793 // Get signal number to use for suspend/resume 2794 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2795 int sig = ::strtol(s, 0, 10); 2796 if (sig > 0 || sig < NSIG) { 2797 SR_signum = sig; 2798 } 2799 } 2800 2801 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2802 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2803 2804 sigemptyset(&SR_sigset); 2805 sigaddset(&SR_sigset, SR_signum); 2806 2807 // Set up signal handler for suspend/resume 2808 act.sa_flags = SA_RESTART|SA_SIGINFO; 2809 act.sa_handler = (void (*)(int)) SR_handler; 2810 2811 // SR_signum is blocked by default. 2812 // 4528190 - We also need to block pthread restart signal (32 on all 2813 // supported Bsd platforms). Note that BsdThreads need to block 2814 // this signal for all threads to work properly. So we don't have 2815 // to use hard-coded signal number when setting up the mask. 2816 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2817 2818 if (sigaction(SR_signum, &act, 0) == -1) { 2819 return -1; 2820 } 2821 2822 // Save signal flag 2823 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2824 return 0; 2825 } 2826 2827 static int sr_notify(OSThread* osthread) { 2828 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2829 assert_status(status == 0, status, "pthread_kill"); 2830 return status; 2831 } 2832 2833 // "Randomly" selected value for how long we want to spin 2834 // before bailing out on suspending a thread, also how often 2835 // we send a signal to a thread we want to resume 2836 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2837 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2838 2839 // returns true on success and false on error - really an error is fatal 2840 // but this seems the normal response to library errors 2841 static bool do_suspend(OSThread* osthread) { 2842 assert(osthread->sr.is_running(), "thread should be running"); 2843 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2844 2845 // mark as suspended and send signal 2846 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2847 // failed to switch, state wasn't running? 2848 ShouldNotReachHere(); 2849 return false; 2850 } 2851 2852 if (sr_notify(osthread) != 0) { 2853 ShouldNotReachHere(); 2854 } 2855 2856 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2857 while (true) { 2858 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2859 break; 2860 } else { 2861 // timeout 2862 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2863 if (cancelled == os::SuspendResume::SR_RUNNING) { 2864 return false; 2865 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2866 // make sure that we consume the signal on the semaphore as well 2867 sr_semaphore.wait(); 2868 break; 2869 } else { 2870 ShouldNotReachHere(); 2871 return false; 2872 } 2873 } 2874 } 2875 2876 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2877 return true; 2878 } 2879 2880 static void do_resume(OSThread* osthread) { 2881 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2882 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2883 2884 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2885 // failed to switch to WAKEUP_REQUEST 2886 ShouldNotReachHere(); 2887 return; 2888 } 2889 2890 while (true) { 2891 if (sr_notify(osthread) == 0) { 2892 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2893 if (osthread->sr.is_running()) { 2894 return; 2895 } 2896 } 2897 } else { 2898 ShouldNotReachHere(); 2899 } 2900 } 2901 2902 guarantee(osthread->sr.is_running(), "Must be running!"); 2903 } 2904 2905 /////////////////////////////////////////////////////////////////////////////////// 2906 // signal handling (except suspend/resume) 2907 2908 // This routine may be used by user applications as a "hook" to catch signals. 2909 // The user-defined signal handler must pass unrecognized signals to this 2910 // routine, and if it returns true (non-zero), then the signal handler must 2911 // return immediately. If the flag "abort_if_unrecognized" is true, then this 2912 // routine will never retun false (zero), but instead will execute a VM panic 2913 // routine kill the process. 2914 // 2915 // If this routine returns false, it is OK to call it again. This allows 2916 // the user-defined signal handler to perform checks either before or after 2917 // the VM performs its own checks. Naturally, the user code would be making 2918 // a serious error if it tried to handle an exception (such as a null check 2919 // or breakpoint) that the VM was generating for its own correct operation. 2920 // 2921 // This routine may recognize any of the following kinds of signals: 2922 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2923 // It should be consulted by handlers for any of those signals. 2924 // 2925 // The caller of this routine must pass in the three arguments supplied 2926 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 2927 // field of the structure passed to sigaction(). This routine assumes that 2928 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2929 // 2930 // Note that the VM will print warnings if it detects conflicting signal 2931 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2932 // 2933 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2934 void* ucontext, 2935 int abort_if_unrecognized); 2936 2937 void signalHandler(int sig, siginfo_t* info, void* uc) { 2938 assert(info != NULL && uc != NULL, "it must be old kernel"); 2939 int orig_errno = errno; // Preserve errno value over signal handler. 2940 JVM_handle_bsd_signal(sig, info, uc, true); 2941 errno = orig_errno; 2942 } 2943 2944 2945 // This boolean allows users to forward their own non-matching signals 2946 // to JVM_handle_bsd_signal, harmlessly. 2947 bool os::Bsd::signal_handlers_are_installed = false; 2948 2949 // For signal-chaining 2950 struct sigaction os::Bsd::sigact[MAXSIGNUM]; 2951 unsigned int os::Bsd::sigs = 0; 2952 bool os::Bsd::libjsig_is_loaded = false; 2953 typedef struct sigaction *(*get_signal_t)(int); 2954 get_signal_t os::Bsd::get_signal_action = NULL; 2955 2956 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2957 struct sigaction *actp = NULL; 2958 2959 if (libjsig_is_loaded) { 2960 // Retrieve the old signal handler from libjsig 2961 actp = (*get_signal_action)(sig); 2962 } 2963 if (actp == NULL) { 2964 // Retrieve the preinstalled signal handler from jvm 2965 actp = get_preinstalled_handler(sig); 2966 } 2967 2968 return actp; 2969 } 2970 2971 static bool call_chained_handler(struct sigaction *actp, int sig, 2972 siginfo_t *siginfo, void *context) { 2973 // Call the old signal handler 2974 if (actp->sa_handler == SIG_DFL) { 2975 // It's more reasonable to let jvm treat it as an unexpected exception 2976 // instead of taking the default action. 2977 return false; 2978 } else if (actp->sa_handler != SIG_IGN) { 2979 if ((actp->sa_flags & SA_NODEFER) == 0) { 2980 // automaticlly block the signal 2981 sigaddset(&(actp->sa_mask), sig); 2982 } 2983 2984 sa_handler_t hand; 2985 sa_sigaction_t sa; 2986 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 2987 // retrieve the chained handler 2988 if (siginfo_flag_set) { 2989 sa = actp->sa_sigaction; 2990 } else { 2991 hand = actp->sa_handler; 2992 } 2993 2994 if ((actp->sa_flags & SA_RESETHAND) != 0) { 2995 actp->sa_handler = SIG_DFL; 2996 } 2997 2998 // try to honor the signal mask 2999 sigset_t oset; 3000 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3001 3002 // call into the chained handler 3003 if (siginfo_flag_set) { 3004 (*sa)(sig, siginfo, context); 3005 } else { 3006 (*hand)(sig); 3007 } 3008 3009 // restore the signal mask 3010 pthread_sigmask(SIG_SETMASK, &oset, 0); 3011 } 3012 // Tell jvm's signal handler the signal is taken care of. 3013 return true; 3014 } 3015 3016 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3017 bool chained = false; 3018 // signal-chaining 3019 if (UseSignalChaining) { 3020 struct sigaction *actp = get_chained_signal_action(sig); 3021 if (actp != NULL) { 3022 chained = call_chained_handler(actp, sig, siginfo, context); 3023 } 3024 } 3025 return chained; 3026 } 3027 3028 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3029 if ((((unsigned int)1 << sig) & sigs) != 0) { 3030 return &sigact[sig]; 3031 } 3032 return NULL; 3033 } 3034 3035 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3036 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3037 sigact[sig] = oldAct; 3038 sigs |= (unsigned int)1 << sig; 3039 } 3040 3041 // for diagnostic 3042 int os::Bsd::sigflags[MAXSIGNUM]; 3043 3044 int os::Bsd::get_our_sigflags(int sig) { 3045 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3046 return sigflags[sig]; 3047 } 3048 3049 void os::Bsd::set_our_sigflags(int sig, int flags) { 3050 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3051 sigflags[sig] = flags; 3052 } 3053 3054 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3055 // Check for overwrite. 3056 struct sigaction oldAct; 3057 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3058 3059 void* oldhand = oldAct.sa_sigaction 3060 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3061 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3062 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3063 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3064 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3065 if (AllowUserSignalHandlers || !set_installed) { 3066 // Do not overwrite; user takes responsibility to forward to us. 3067 return; 3068 } else if (UseSignalChaining) { 3069 // save the old handler in jvm 3070 save_preinstalled_handler(sig, oldAct); 3071 // libjsig also interposes the sigaction() call below and saves the 3072 // old sigaction on it own. 3073 } else { 3074 fatal("Encountered unexpected pre-existing sigaction handler " 3075 "%#lx for signal %d.", (long)oldhand, sig); 3076 } 3077 } 3078 3079 struct sigaction sigAct; 3080 sigfillset(&(sigAct.sa_mask)); 3081 sigAct.sa_handler = SIG_DFL; 3082 if (!set_installed) { 3083 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3084 } else { 3085 sigAct.sa_sigaction = signalHandler; 3086 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3087 } 3088 #ifdef __APPLE__ 3089 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3090 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3091 // if the signal handler declares it will handle it on alternate stack. 3092 // Notice we only declare we will handle it on alt stack, but we are not 3093 // actually going to use real alt stack - this is just a workaround. 3094 // Please see ux_exception.c, method catch_mach_exception_raise for details 3095 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3096 if (sig == SIGSEGV) { 3097 sigAct.sa_flags |= SA_ONSTACK; 3098 } 3099 #endif 3100 3101 // Save flags, which are set by ours 3102 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3103 sigflags[sig] = sigAct.sa_flags; 3104 3105 int ret = sigaction(sig, &sigAct, &oldAct); 3106 assert(ret == 0, "check"); 3107 3108 void* oldhand2 = oldAct.sa_sigaction 3109 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3110 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3111 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3112 } 3113 3114 // install signal handlers for signals that HotSpot needs to 3115 // handle in order to support Java-level exception handling. 3116 3117 void os::Bsd::install_signal_handlers() { 3118 if (!signal_handlers_are_installed) { 3119 signal_handlers_are_installed = true; 3120 3121 // signal-chaining 3122 typedef void (*signal_setting_t)(); 3123 signal_setting_t begin_signal_setting = NULL; 3124 signal_setting_t end_signal_setting = NULL; 3125 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3126 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3127 if (begin_signal_setting != NULL) { 3128 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3129 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3130 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3131 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3132 libjsig_is_loaded = true; 3133 assert(UseSignalChaining, "should enable signal-chaining"); 3134 } 3135 if (libjsig_is_loaded) { 3136 // Tell libjsig jvm is setting signal handlers 3137 (*begin_signal_setting)(); 3138 } 3139 3140 set_signal_handler(SIGSEGV, true); 3141 set_signal_handler(SIGPIPE, true); 3142 set_signal_handler(SIGBUS, true); 3143 set_signal_handler(SIGILL, true); 3144 set_signal_handler(SIGFPE, true); 3145 set_signal_handler(SIGXFSZ, true); 3146 3147 #if defined(__APPLE__) 3148 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3149 // signals caught and handled by the JVM. To work around this, we reset the mach task 3150 // signal handler that's placed on our process by CrashReporter. This disables 3151 // CrashReporter-based reporting. 3152 // 3153 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3154 // on caught fatal signals. 3155 // 3156 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3157 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3158 // exception handling, while leaving the standard BSD signal handlers functional. 3159 kern_return_t kr; 3160 kr = task_set_exception_ports(mach_task_self(), 3161 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3162 MACH_PORT_NULL, 3163 EXCEPTION_STATE_IDENTITY, 3164 MACHINE_THREAD_STATE); 3165 3166 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3167 #endif 3168 3169 if (libjsig_is_loaded) { 3170 // Tell libjsig jvm finishes setting signal handlers 3171 (*end_signal_setting)(); 3172 } 3173 3174 // We don't activate signal checker if libjsig is in place, we trust ourselves 3175 // and if UserSignalHandler is installed all bets are off 3176 if (CheckJNICalls) { 3177 if (libjsig_is_loaded) { 3178 if (PrintJNIResolving) { 3179 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3180 } 3181 check_signals = false; 3182 } 3183 if (AllowUserSignalHandlers) { 3184 if (PrintJNIResolving) { 3185 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3186 } 3187 check_signals = false; 3188 } 3189 } 3190 } 3191 } 3192 3193 3194 ///// 3195 // glibc on Bsd platform uses non-documented flag 3196 // to indicate, that some special sort of signal 3197 // trampoline is used. 3198 // We will never set this flag, and we should 3199 // ignore this flag in our diagnostic 3200 #ifdef SIGNIFICANT_SIGNAL_MASK 3201 #undef SIGNIFICANT_SIGNAL_MASK 3202 #endif 3203 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3204 3205 static const char* get_signal_handler_name(address handler, 3206 char* buf, int buflen) { 3207 int offset; 3208 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3209 if (found) { 3210 // skip directory names 3211 const char *p1, *p2; 3212 p1 = buf; 3213 size_t len = strlen(os::file_separator()); 3214 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3215 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3216 } else { 3217 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3218 } 3219 return buf; 3220 } 3221 3222 static void print_signal_handler(outputStream* st, int sig, 3223 char* buf, size_t buflen) { 3224 struct sigaction sa; 3225 3226 sigaction(sig, NULL, &sa); 3227 3228 // See comment for SIGNIFICANT_SIGNAL_MASK define 3229 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3230 3231 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3232 3233 address handler = (sa.sa_flags & SA_SIGINFO) 3234 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3235 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3236 3237 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3238 st->print("SIG_DFL"); 3239 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3240 st->print("SIG_IGN"); 3241 } else { 3242 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3243 } 3244 3245 st->print(", sa_mask[0]="); 3246 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3247 3248 address rh = VMError::get_resetted_sighandler(sig); 3249 // May be, handler was resetted by VMError? 3250 if (rh != NULL) { 3251 handler = rh; 3252 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3253 } 3254 3255 st->print(", sa_flags="); 3256 os::Posix::print_sa_flags(st, sa.sa_flags); 3257 3258 // Check: is it our handler? 3259 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3260 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3261 // It is our signal handler 3262 // check for flags, reset system-used one! 3263 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3264 st->print( 3265 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3266 os::Bsd::get_our_sigflags(sig)); 3267 } 3268 } 3269 st->cr(); 3270 } 3271 3272 3273 #define DO_SIGNAL_CHECK(sig) \ 3274 do { \ 3275 if (!sigismember(&check_signal_done, sig)) { \ 3276 os::Bsd::check_signal_handler(sig); \ 3277 } \ 3278 } while (0) 3279 3280 // This method is a periodic task to check for misbehaving JNI applications 3281 // under CheckJNI, we can add any periodic checks here 3282 3283 void os::run_periodic_checks() { 3284 3285 if (check_signals == false) return; 3286 3287 // SEGV and BUS if overridden could potentially prevent 3288 // generation of hs*.log in the event of a crash, debugging 3289 // such a case can be very challenging, so we absolutely 3290 // check the following for a good measure: 3291 DO_SIGNAL_CHECK(SIGSEGV); 3292 DO_SIGNAL_CHECK(SIGILL); 3293 DO_SIGNAL_CHECK(SIGFPE); 3294 DO_SIGNAL_CHECK(SIGBUS); 3295 DO_SIGNAL_CHECK(SIGPIPE); 3296 DO_SIGNAL_CHECK(SIGXFSZ); 3297 3298 3299 // ReduceSignalUsage allows the user to override these handlers 3300 // see comments at the very top and jvm_solaris.h 3301 if (!ReduceSignalUsage) { 3302 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3303 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3304 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3305 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3306 } 3307 3308 DO_SIGNAL_CHECK(SR_signum); 3309 } 3310 3311 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3312 3313 static os_sigaction_t os_sigaction = NULL; 3314 3315 void os::Bsd::check_signal_handler(int sig) { 3316 char buf[O_BUFLEN]; 3317 address jvmHandler = NULL; 3318 3319 3320 struct sigaction act; 3321 if (os_sigaction == NULL) { 3322 // only trust the default sigaction, in case it has been interposed 3323 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3324 if (os_sigaction == NULL) return; 3325 } 3326 3327 os_sigaction(sig, (struct sigaction*)NULL, &act); 3328 3329 3330 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3331 3332 address thisHandler = (act.sa_flags & SA_SIGINFO) 3333 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3334 : CAST_FROM_FN_PTR(address, act.sa_handler); 3335 3336 3337 switch (sig) { 3338 case SIGSEGV: 3339 case SIGBUS: 3340 case SIGFPE: 3341 case SIGPIPE: 3342 case SIGILL: 3343 case SIGXFSZ: 3344 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3345 break; 3346 3347 case SHUTDOWN1_SIGNAL: 3348 case SHUTDOWN2_SIGNAL: 3349 case SHUTDOWN3_SIGNAL: 3350 case BREAK_SIGNAL: 3351 jvmHandler = (address)user_handler(); 3352 break; 3353 3354 default: 3355 if (sig == SR_signum) { 3356 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3357 } else { 3358 return; 3359 } 3360 break; 3361 } 3362 3363 if (thisHandler != jvmHandler) { 3364 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3365 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3366 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3367 // No need to check this sig any longer 3368 sigaddset(&check_signal_done, sig); 3369 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3370 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3371 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3372 exception_name(sig, buf, O_BUFLEN)); 3373 } 3374 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3375 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3376 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3377 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3378 // No need to check this sig any longer 3379 sigaddset(&check_signal_done, sig); 3380 } 3381 3382 // Dump all the signal 3383 if (sigismember(&check_signal_done, sig)) { 3384 print_signal_handlers(tty, buf, O_BUFLEN); 3385 } 3386 } 3387 3388 extern void report_error(char* file_name, int line_no, char* title, 3389 char* format, ...); 3390 3391 extern bool signal_name(int signo, char* buf, size_t len); 3392 3393 const char* os::exception_name(int exception_code, char* buf, size_t size) { 3394 if (0 < exception_code && exception_code <= SIGRTMAX) { 3395 // signal 3396 if (!signal_name(exception_code, buf, size)) { 3397 jio_snprintf(buf, size, "SIG%d", exception_code); 3398 } 3399 return buf; 3400 } else { 3401 return NULL; 3402 } 3403 } 3404 3405 // this is called _before_ the most of global arguments have been parsed 3406 void os::init(void) { 3407 char dummy; // used to get a guess on initial stack address 3408 // first_hrtime = gethrtime(); 3409 3410 // With BsdThreads the JavaMain thread pid (primordial thread) 3411 // is different than the pid of the java launcher thread. 3412 // So, on Bsd, the launcher thread pid is passed to the VM 3413 // via the sun.java.launcher.pid property. 3414 // Use this property instead of getpid() if it was correctly passed. 3415 // See bug 6351349. 3416 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3417 3418 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3419 3420 clock_tics_per_sec = CLK_TCK; 3421 3422 init_random(1234567); 3423 3424 ThreadCritical::initialize(); 3425 3426 Bsd::set_page_size(getpagesize()); 3427 if (Bsd::page_size() == -1) { 3428 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", strerror(errno)); 3429 } 3430 init_page_sizes((size_t) Bsd::page_size()); 3431 3432 Bsd::initialize_system_info(); 3433 3434 // main_thread points to the aboriginal thread 3435 Bsd::_main_thread = pthread_self(); 3436 3437 Bsd::clock_init(); 3438 initial_time_count = javaTimeNanos(); 3439 3440 #ifdef __APPLE__ 3441 // XXXDARWIN 3442 // Work around the unaligned VM callbacks in hotspot's 3443 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3444 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3445 // alignment when doing symbol lookup. To work around this, we force early 3446 // binding of all symbols now, thus binding when alignment is known-good. 3447 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3448 #endif 3449 } 3450 3451 // To install functions for atexit system call 3452 extern "C" { 3453 static void perfMemory_exit_helper() { 3454 perfMemory_exit(); 3455 } 3456 } 3457 3458 // this is called _after_ the global arguments have been parsed 3459 jint os::init_2(void) { 3460 // Allocate a single page and mark it as readable for safepoint polling 3461 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3462 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3463 3464 os::set_polling_page(polling_page); 3465 3466 #ifndef PRODUCT 3467 if (Verbose && PrintMiscellaneous) { 3468 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", 3469 (intptr_t)polling_page); 3470 } 3471 #endif 3472 3473 if (!UseMembar) { 3474 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3475 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3476 os::set_memory_serialize_page(mem_serialize_page); 3477 3478 #ifndef PRODUCT 3479 if (Verbose && PrintMiscellaneous) { 3480 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", 3481 (intptr_t)mem_serialize_page); 3482 } 3483 #endif 3484 } 3485 3486 // initialize suspend/resume support - must do this before signal_sets_init() 3487 if (SR_initialize() != 0) { 3488 perror("SR_initialize failed"); 3489 return JNI_ERR; 3490 } 3491 3492 Bsd::signal_sets_init(); 3493 Bsd::install_signal_handlers(); 3494 3495 // Check minimum allowable stack size for thread creation and to initialize 3496 // the java system classes, including StackOverflowError - depends on page 3497 // size. Add a page for compiler2 recursion in main thread. 3498 // Add in 2*BytesPerWord times page size to account for VM stack during 3499 // class initialization depending on 32 or 64 bit VM. 3500 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3501 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3502 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3503 3504 size_t threadStackSizeInBytes = ThreadStackSize * K; 3505 if (threadStackSizeInBytes != 0 && 3506 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3507 tty->print_cr("\nThe stack size specified is too small, " 3508 "Specify at least %dk", 3509 os::Bsd::min_stack_allowed/ K); 3510 return JNI_ERR; 3511 } 3512 3513 // Make the stack size a multiple of the page size so that 3514 // the yellow/red zones can be guarded. 3515 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3516 vm_page_size())); 3517 3518 if (MaxFDLimit) { 3519 // set the number of file descriptors to max. print out error 3520 // if getrlimit/setrlimit fails but continue regardless. 3521 struct rlimit nbr_files; 3522 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3523 if (status != 0) { 3524 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3525 perror("os::init_2 getrlimit failed"); 3526 } 3527 } else { 3528 nbr_files.rlim_cur = nbr_files.rlim_max; 3529 3530 #ifdef __APPLE__ 3531 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3532 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3533 // be used instead 3534 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3535 #endif 3536 3537 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3538 if (status != 0) { 3539 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3540 perror("os::init_2 setrlimit failed"); 3541 } 3542 } 3543 } 3544 } 3545 3546 // at-exit methods are called in the reverse order of their registration. 3547 // atexit functions are called on return from main or as a result of a 3548 // call to exit(3C). There can be only 32 of these functions registered 3549 // and atexit() does not set errno. 3550 3551 if (PerfAllowAtExitRegistration) { 3552 // only register atexit functions if PerfAllowAtExitRegistration is set. 3553 // atexit functions can be delayed until process exit time, which 3554 // can be problematic for embedded VM situations. Embedded VMs should 3555 // call DestroyJavaVM() to assure that VM resources are released. 3556 3557 // note: perfMemory_exit_helper atexit function may be removed in 3558 // the future if the appropriate cleanup code can be added to the 3559 // VM_Exit VMOperation's doit method. 3560 if (atexit(perfMemory_exit_helper) != 0) { 3561 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3562 } 3563 } 3564 3565 // initialize thread priority policy 3566 prio_init(); 3567 3568 #ifdef __APPLE__ 3569 // dynamically link to objective c gc registration 3570 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3571 if (handleLibObjc != NULL) { 3572 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3573 } 3574 #endif 3575 3576 return JNI_OK; 3577 } 3578 3579 // Mark the polling page as unreadable 3580 void os::make_polling_page_unreadable(void) { 3581 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3582 fatal("Could not disable polling page"); 3583 } 3584 } 3585 3586 // Mark the polling page as readable 3587 void os::make_polling_page_readable(void) { 3588 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3589 fatal("Could not enable polling page"); 3590 } 3591 } 3592 3593 int os::active_processor_count() { 3594 return _processor_count; 3595 } 3596 3597 void os::set_native_thread_name(const char *name) { 3598 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3599 // This is only supported in Snow Leopard and beyond 3600 if (name != NULL) { 3601 // Add a "Java: " prefix to the name 3602 char buf[MAXTHREADNAMESIZE]; 3603 snprintf(buf, sizeof(buf), "Java: %s", name); 3604 pthread_setname_np(buf); 3605 } 3606 #endif 3607 } 3608 3609 bool os::distribute_processes(uint length, uint* distribution) { 3610 // Not yet implemented. 3611 return false; 3612 } 3613 3614 bool os::bind_to_processor(uint processor_id) { 3615 // Not yet implemented. 3616 return false; 3617 } 3618 3619 void os::SuspendedThreadTask::internal_do_task() { 3620 if (do_suspend(_thread->osthread())) { 3621 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3622 do_task(context); 3623 do_resume(_thread->osthread()); 3624 } 3625 } 3626 3627 /// 3628 class PcFetcher : public os::SuspendedThreadTask { 3629 public: 3630 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3631 ExtendedPC result(); 3632 protected: 3633 void do_task(const os::SuspendedThreadTaskContext& context); 3634 private: 3635 ExtendedPC _epc; 3636 }; 3637 3638 ExtendedPC PcFetcher::result() { 3639 guarantee(is_done(), "task is not done yet."); 3640 return _epc; 3641 } 3642 3643 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3644 Thread* thread = context.thread(); 3645 OSThread* osthread = thread->osthread(); 3646 if (osthread->ucontext() != NULL) { 3647 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3648 } else { 3649 // NULL context is unexpected, double-check this is the VMThread 3650 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3651 } 3652 } 3653 3654 // Suspends the target using the signal mechanism and then grabs the PC before 3655 // resuming the target. Used by the flat-profiler only 3656 ExtendedPC os::get_thread_pc(Thread* thread) { 3657 // Make sure that it is called by the watcher for the VMThread 3658 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3659 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3660 3661 PcFetcher fetcher(thread); 3662 fetcher.run(); 3663 return fetcher.result(); 3664 } 3665 3666 //////////////////////////////////////////////////////////////////////////////// 3667 // debug support 3668 3669 bool os::find(address addr, outputStream* st) { 3670 Dl_info dlinfo; 3671 memset(&dlinfo, 0, sizeof(dlinfo)); 3672 if (dladdr(addr, &dlinfo) != 0) { 3673 st->print(PTR_FORMAT ": ", addr); 3674 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3675 st->print("%s+%#x", dlinfo.dli_sname, 3676 addr - (intptr_t)dlinfo.dli_saddr); 3677 } else if (dlinfo.dli_fbase != NULL) { 3678 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3679 } else { 3680 st->print("<absolute address>"); 3681 } 3682 if (dlinfo.dli_fname != NULL) { 3683 st->print(" in %s", dlinfo.dli_fname); 3684 } 3685 if (dlinfo.dli_fbase != NULL) { 3686 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3687 } 3688 st->cr(); 3689 3690 if (Verbose) { 3691 // decode some bytes around the PC 3692 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3693 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3694 address lowest = (address) dlinfo.dli_sname; 3695 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3696 if (begin < lowest) begin = lowest; 3697 Dl_info dlinfo2; 3698 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3699 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3700 end = (address) dlinfo2.dli_saddr; 3701 } 3702 Disassembler::decode(begin, end, st); 3703 } 3704 return true; 3705 } 3706 return false; 3707 } 3708 3709 //////////////////////////////////////////////////////////////////////////////// 3710 // misc 3711 3712 // This does not do anything on Bsd. This is basically a hook for being 3713 // able to use structured exception handling (thread-local exception filters) 3714 // on, e.g., Win32. 3715 void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3716 const methodHandle& method, JavaCallArguments* args, 3717 Thread* thread) { 3718 f(value, method, args, thread); 3719 } 3720 3721 void os::print_statistics() { 3722 } 3723 3724 int os::message_box(const char* title, const char* message) { 3725 int i; 3726 fdStream err(defaultStream::error_fd()); 3727 for (i = 0; i < 78; i++) err.print_raw("="); 3728 err.cr(); 3729 err.print_raw_cr(title); 3730 for (i = 0; i < 78; i++) err.print_raw("-"); 3731 err.cr(); 3732 err.print_raw_cr(message); 3733 for (i = 0; i < 78; i++) err.print_raw("="); 3734 err.cr(); 3735 3736 char buf[16]; 3737 // Prevent process from exiting upon "read error" without consuming all CPU 3738 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3739 3740 return buf[0] == 'y' || buf[0] == 'Y'; 3741 } 3742 3743 int os::stat(const char *path, struct stat *sbuf) { 3744 char pathbuf[MAX_PATH]; 3745 if (strlen(path) > MAX_PATH - 1) { 3746 errno = ENAMETOOLONG; 3747 return -1; 3748 } 3749 os::native_path(strcpy(pathbuf, path)); 3750 return ::stat(pathbuf, sbuf); 3751 } 3752 3753 bool os::check_heap(bool force) { 3754 return true; 3755 } 3756 3757 // Is a (classpath) directory empty? 3758 bool os::dir_is_empty(const char* path) { 3759 DIR *dir = NULL; 3760 struct dirent *ptr; 3761 3762 dir = opendir(path); 3763 if (dir == NULL) return true; 3764 3765 // Scan the directory 3766 bool result = true; 3767 char buf[sizeof(struct dirent) + MAX_PATH]; 3768 while (result && (ptr = ::readdir(dir)) != NULL) { 3769 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3770 result = false; 3771 } 3772 } 3773 closedir(dir); 3774 return result; 3775 } 3776 3777 // This code originates from JDK's sysOpen and open64_w 3778 // from src/solaris/hpi/src/system_md.c 3779 3780 int os::open(const char *path, int oflag, int mode) { 3781 if (strlen(path) > MAX_PATH - 1) { 3782 errno = ENAMETOOLONG; 3783 return -1; 3784 } 3785 int fd; 3786 3787 fd = ::open(path, oflag, mode); 3788 if (fd == -1) return -1; 3789 3790 // If the open succeeded, the file might still be a directory 3791 { 3792 struct stat buf; 3793 int ret = ::fstat(fd, &buf); 3794 int st_mode = buf.st_mode; 3795 3796 if (ret != -1) { 3797 if ((st_mode & S_IFMT) == S_IFDIR) { 3798 errno = EISDIR; 3799 ::close(fd); 3800 return -1; 3801 } 3802 } else { 3803 ::close(fd); 3804 return -1; 3805 } 3806 } 3807 3808 // All file descriptors that are opened in the JVM and not 3809 // specifically destined for a subprocess should have the 3810 // close-on-exec flag set. If we don't set it, then careless 3rd 3811 // party native code might fork and exec without closing all 3812 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3813 // UNIXProcess.c), and this in turn might: 3814 // 3815 // - cause end-of-file to fail to be detected on some file 3816 // descriptors, resulting in mysterious hangs, or 3817 // 3818 // - might cause an fopen in the subprocess to fail on a system 3819 // suffering from bug 1085341. 3820 // 3821 // (Yes, the default setting of the close-on-exec flag is a Unix 3822 // design flaw) 3823 // 3824 // See: 3825 // 1085341: 32-bit stdio routines should support file descriptors >255 3826 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3827 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3828 // 3829 #ifdef FD_CLOEXEC 3830 { 3831 int flags = ::fcntl(fd, F_GETFD); 3832 if (flags != -1) { 3833 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3834 } 3835 } 3836 #endif 3837 3838 return fd; 3839 } 3840 3841 3842 // create binary file, rewriting existing file if required 3843 int os::create_binary_file(const char* path, bool rewrite_existing) { 3844 int oflags = O_WRONLY | O_CREAT; 3845 if (!rewrite_existing) { 3846 oflags |= O_EXCL; 3847 } 3848 return ::open(path, oflags, S_IREAD | S_IWRITE); 3849 } 3850 3851 // return current position of file pointer 3852 jlong os::current_file_offset(int fd) { 3853 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3854 } 3855 3856 // move file pointer to the specified offset 3857 jlong os::seek_to_file_offset(int fd, jlong offset) { 3858 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3859 } 3860 3861 // This code originates from JDK's sysAvailable 3862 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3863 3864 int os::available(int fd, jlong *bytes) { 3865 jlong cur, end; 3866 int mode; 3867 struct stat buf; 3868 3869 if (::fstat(fd, &buf) >= 0) { 3870 mode = buf.st_mode; 3871 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3872 int n; 3873 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3874 *bytes = n; 3875 return 1; 3876 } 3877 } 3878 } 3879 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3880 return 0; 3881 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3882 return 0; 3883 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3884 return 0; 3885 } 3886 *bytes = end - cur; 3887 return 1; 3888 } 3889 3890 // Map a block of memory. 3891 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3892 char *addr, size_t bytes, bool read_only, 3893 bool allow_exec) { 3894 int prot; 3895 int flags; 3896 3897 if (read_only) { 3898 prot = PROT_READ; 3899 flags = MAP_SHARED; 3900 } else { 3901 prot = PROT_READ | PROT_WRITE; 3902 flags = MAP_PRIVATE; 3903 } 3904 3905 if (allow_exec) { 3906 prot |= PROT_EXEC; 3907 } 3908 3909 if (addr != NULL) { 3910 flags |= MAP_FIXED; 3911 } 3912 3913 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3914 fd, file_offset); 3915 if (mapped_address == MAP_FAILED) { 3916 return NULL; 3917 } 3918 return mapped_address; 3919 } 3920 3921 3922 // Remap a block of memory. 3923 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3924 char *addr, size_t bytes, bool read_only, 3925 bool allow_exec) { 3926 // same as map_memory() on this OS 3927 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3928 allow_exec); 3929 } 3930 3931 3932 // Unmap a block of memory. 3933 bool os::pd_unmap_memory(char* addr, size_t bytes) { 3934 return munmap(addr, bytes) == 0; 3935 } 3936 3937 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3938 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 3939 // of a thread. 3940 // 3941 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 3942 // the fast estimate available on the platform. 3943 3944 jlong os::current_thread_cpu_time() { 3945 #ifdef __APPLE__ 3946 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 3947 #else 3948 Unimplemented(); 3949 return 0; 3950 #endif 3951 } 3952 3953 jlong os::thread_cpu_time(Thread* thread) { 3954 #ifdef __APPLE__ 3955 return os::thread_cpu_time(thread, true /* user + sys */); 3956 #else 3957 Unimplemented(); 3958 return 0; 3959 #endif 3960 } 3961 3962 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 3963 #ifdef __APPLE__ 3964 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 3965 #else 3966 Unimplemented(); 3967 return 0; 3968 #endif 3969 } 3970 3971 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 3972 #ifdef __APPLE__ 3973 struct thread_basic_info tinfo; 3974 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 3975 kern_return_t kr; 3976 thread_t mach_thread; 3977 3978 mach_thread = thread->osthread()->thread_id(); 3979 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 3980 if (kr != KERN_SUCCESS) { 3981 return -1; 3982 } 3983 3984 if (user_sys_cpu_time) { 3985 jlong nanos; 3986 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 3987 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 3988 return nanos; 3989 } else { 3990 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 3991 } 3992 #else 3993 Unimplemented(); 3994 return 0; 3995 #endif 3996 } 3997 3998 3999 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4000 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4001 info_ptr->may_skip_backward = false; // elapsed time not wall time 4002 info_ptr->may_skip_forward = false; // elapsed time not wall time 4003 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4004 } 4005 4006 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4007 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4008 info_ptr->may_skip_backward = false; // elapsed time not wall time 4009 info_ptr->may_skip_forward = false; // elapsed time not wall time 4010 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4011 } 4012 4013 bool os::is_thread_cpu_time_supported() { 4014 #ifdef __APPLE__ 4015 return true; 4016 #else 4017 return false; 4018 #endif 4019 } 4020 4021 // System loadavg support. Returns -1 if load average cannot be obtained. 4022 // Bsd doesn't yet have a (official) notion of processor sets, 4023 // so just return the system wide load average. 4024 int os::loadavg(double loadavg[], int nelem) { 4025 return ::getloadavg(loadavg, nelem); 4026 } 4027 4028 void os::pause() { 4029 char filename[MAX_PATH]; 4030 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4031 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4032 } else { 4033 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4034 } 4035 4036 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4037 if (fd != -1) { 4038 struct stat buf; 4039 ::close(fd); 4040 while (::stat(filename, &buf) == 0) { 4041 (void)::poll(NULL, 0, 100); 4042 } 4043 } else { 4044 jio_fprintf(stderr, 4045 "Could not open pause file '%s', continuing immediately.\n", filename); 4046 } 4047 } 4048 4049 4050 // Refer to the comments in os_solaris.cpp park-unpark. The next two 4051 // comment paragraphs are worth repeating here: 4052 // 4053 // Assumption: 4054 // Only one parker can exist on an event, which is why we allocate 4055 // them per-thread. Multiple unparkers can coexist. 4056 // 4057 // _Event serves as a restricted-range semaphore. 4058 // -1 : thread is blocked, i.e. there is a waiter 4059 // 0 : neutral: thread is running or ready, 4060 // could have been signaled after a wait started 4061 // 1 : signaled - thread is running or ready 4062 // 4063 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4064 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4065 // For specifics regarding the bug see GLIBC BUGID 261237 : 4066 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4067 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4068 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4069 // is used. (The simple C test-case provided in the GLIBC bug report manifests the 4070 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4071 // and monitorenter when we're using 1-0 locking. All those operations may result in 4072 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4073 // of libpthread avoids the problem, but isn't practical. 4074 // 4075 // Possible remedies: 4076 // 4077 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4078 // This is palliative and probabilistic, however. If the thread is preempted 4079 // between the call to compute_abstime() and pthread_cond_timedwait(), more 4080 // than the minimum period may have passed, and the abstime may be stale (in the 4081 // past) resultin in a hang. Using this technique reduces the odds of a hang 4082 // but the JVM is still vulnerable, particularly on heavily loaded systems. 4083 // 4084 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4085 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4086 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4087 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4088 // thread. 4089 // 4090 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4091 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4092 // a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4093 // This also works well. In fact it avoids kernel-level scalability impediments 4094 // on certain platforms that don't handle lots of active pthread_cond_timedwait() 4095 // timers in a graceful fashion. 4096 // 4097 // 4. When the abstime value is in the past it appears that control returns 4098 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4099 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4100 // can avoid the problem by reinitializing the condvar -- by cond_destroy() 4101 // followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4102 // It may be possible to avoid reinitialization by checking the return 4103 // value from pthread_cond_timedwait(). In addition to reinitializing the 4104 // condvar we must establish the invariant that cond_signal() is only called 4105 // within critical sections protected by the adjunct mutex. This prevents 4106 // cond_signal() from "seeing" a condvar that's in the midst of being 4107 // reinitialized or that is corrupt. Sadly, this invariant obviates the 4108 // desirable signal-after-unlock optimization that avoids futile context switching. 4109 // 4110 // I'm also concerned that some versions of NTPL might allocate an auxilliary 4111 // structure when a condvar is used or initialized. cond_destroy() would 4112 // release the helper structure. Our reinitialize-after-timedwait fix 4113 // put excessive stress on malloc/free and locks protecting the c-heap. 4114 // 4115 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4116 // It may be possible to refine (4) by checking the kernel and NTPL verisons 4117 // and only enabling the work-around for vulnerable environments. 4118 4119 // utility to compute the abstime argument to timedwait: 4120 // millis is the relative timeout time 4121 // abstime will be the absolute timeout time 4122 // TODO: replace compute_abstime() with unpackTime() 4123 4124 static struct timespec* compute_abstime(struct timespec* abstime, 4125 jlong millis) { 4126 if (millis < 0) millis = 0; 4127 struct timeval now; 4128 int status = gettimeofday(&now, NULL); 4129 assert(status == 0, "gettimeofday"); 4130 jlong seconds = millis / 1000; 4131 millis %= 1000; 4132 if (seconds > 50000000) { // see man cond_timedwait(3T) 4133 seconds = 50000000; 4134 } 4135 abstime->tv_sec = now.tv_sec + seconds; 4136 long usec = now.tv_usec + millis * 1000; 4137 if (usec >= 1000000) { 4138 abstime->tv_sec += 1; 4139 usec -= 1000000; 4140 } 4141 abstime->tv_nsec = usec * 1000; 4142 return abstime; 4143 } 4144 4145 void os::PlatformEvent::park() { // AKA "down()" 4146 // Transitions for _Event: 4147 // -1 => -1 : illegal 4148 // 1 => 0 : pass - return immediately 4149 // 0 => -1 : block; then set _Event to 0 before returning 4150 4151 // Invariant: Only the thread associated with the Event/PlatformEvent 4152 // may call park(). 4153 // TODO: assert that _Assoc != NULL or _Assoc == Self 4154 assert(_nParked == 0, "invariant"); 4155 4156 int v; 4157 for (;;) { 4158 v = _Event; 4159 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4160 } 4161 guarantee(v >= 0, "invariant"); 4162 if (v == 0) { 4163 // Do this the hard way by blocking ... 4164 int status = pthread_mutex_lock(_mutex); 4165 assert_status(status == 0, status, "mutex_lock"); 4166 guarantee(_nParked == 0, "invariant"); 4167 ++_nParked; 4168 while (_Event < 0) { 4169 status = pthread_cond_wait(_cond, _mutex); 4170 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4171 // Treat this the same as if the wait was interrupted 4172 if (status == ETIMEDOUT) { status = EINTR; } 4173 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4174 } 4175 --_nParked; 4176 4177 _Event = 0; 4178 status = pthread_mutex_unlock(_mutex); 4179 assert_status(status == 0, status, "mutex_unlock"); 4180 // Paranoia to ensure our locked and lock-free paths interact 4181 // correctly with each other. 4182 OrderAccess::fence(); 4183 } 4184 guarantee(_Event >= 0, "invariant"); 4185 } 4186 4187 int os::PlatformEvent::park(jlong millis) { 4188 // Transitions for _Event: 4189 // -1 => -1 : illegal 4190 // 1 => 0 : pass - return immediately 4191 // 0 => -1 : block; then set _Event to 0 before returning 4192 4193 guarantee(_nParked == 0, "invariant"); 4194 4195 int v; 4196 for (;;) { 4197 v = _Event; 4198 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4199 } 4200 guarantee(v >= 0, "invariant"); 4201 if (v != 0) return OS_OK; 4202 4203 // We do this the hard way, by blocking the thread. 4204 // Consider enforcing a minimum timeout value. 4205 struct timespec abst; 4206 compute_abstime(&abst, millis); 4207 4208 int ret = OS_TIMEOUT; 4209 int status = pthread_mutex_lock(_mutex); 4210 assert_status(status == 0, status, "mutex_lock"); 4211 guarantee(_nParked == 0, "invariant"); 4212 ++_nParked; 4213 4214 // Object.wait(timo) will return because of 4215 // (a) notification 4216 // (b) timeout 4217 // (c) thread.interrupt 4218 // 4219 // Thread.interrupt and object.notify{All} both call Event::set. 4220 // That is, we treat thread.interrupt as a special case of notification. 4221 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4222 // We assume all ETIME returns are valid. 4223 // 4224 // TODO: properly differentiate simultaneous notify+interrupt. 4225 // In that case, we should propagate the notify to another waiter. 4226 4227 while (_Event < 0) { 4228 status = pthread_cond_timedwait(_cond, _mutex, &abst); 4229 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4230 pthread_cond_destroy(_cond); 4231 pthread_cond_init(_cond, NULL); 4232 } 4233 assert_status(status == 0 || status == EINTR || 4234 status == ETIMEDOUT, 4235 status, "cond_timedwait"); 4236 if (!FilterSpuriousWakeups) break; // previous semantics 4237 if (status == ETIMEDOUT) break; 4238 // We consume and ignore EINTR and spurious wakeups. 4239 } 4240 --_nParked; 4241 if (_Event >= 0) { 4242 ret = OS_OK; 4243 } 4244 _Event = 0; 4245 status = pthread_mutex_unlock(_mutex); 4246 assert_status(status == 0, status, "mutex_unlock"); 4247 assert(_nParked == 0, "invariant"); 4248 // Paranoia to ensure our locked and lock-free paths interact 4249 // correctly with each other. 4250 OrderAccess::fence(); 4251 return ret; 4252 } 4253 4254 void os::PlatformEvent::unpark() { 4255 // Transitions for _Event: 4256 // 0 => 1 : just return 4257 // 1 => 1 : just return 4258 // -1 => either 0 or 1; must signal target thread 4259 // That is, we can safely transition _Event from -1 to either 4260 // 0 or 1. 4261 // See also: "Semaphores in Plan 9" by Mullender & Cox 4262 // 4263 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4264 // that it will take two back-to-back park() calls for the owning 4265 // thread to block. This has the benefit of forcing a spurious return 4266 // from the first park() call after an unpark() call which will help 4267 // shake out uses of park() and unpark() without condition variables. 4268 4269 if (Atomic::xchg(1, &_Event) >= 0) return; 4270 4271 // Wait for the thread associated with the event to vacate 4272 int status = pthread_mutex_lock(_mutex); 4273 assert_status(status == 0, status, "mutex_lock"); 4274 int AnyWaiters = _nParked; 4275 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4276 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4277 AnyWaiters = 0; 4278 pthread_cond_signal(_cond); 4279 } 4280 status = pthread_mutex_unlock(_mutex); 4281 assert_status(status == 0, status, "mutex_unlock"); 4282 if (AnyWaiters != 0) { 4283 // Note that we signal() *after* dropping the lock for "immortal" Events. 4284 // This is safe and avoids a common class of futile wakeups. In rare 4285 // circumstances this can cause a thread to return prematurely from 4286 // cond_{timed}wait() but the spurious wakeup is benign and the victim 4287 // will simply re-test the condition and re-park itself. 4288 // This provides particular benefit if the underlying platform does not 4289 // provide wait morphing. 4290 status = pthread_cond_signal(_cond); 4291 assert_status(status == 0, status, "cond_signal"); 4292 } 4293 } 4294 4295 4296 // JSR166 4297 // ------------------------------------------------------- 4298 4299 // The solaris and bsd implementations of park/unpark are fairly 4300 // conservative for now, but can be improved. They currently use a 4301 // mutex/condvar pair, plus a a count. 4302 // Park decrements count if > 0, else does a condvar wait. Unpark 4303 // sets count to 1 and signals condvar. Only one thread ever waits 4304 // on the condvar. Contention seen when trying to park implies that someone 4305 // is unparking you, so don't wait. And spurious returns are fine, so there 4306 // is no need to track notifications. 4307 4308 #define MAX_SECS 100000000 4309 4310 // This code is common to bsd and solaris and will be moved to a 4311 // common place in dolphin. 4312 // 4313 // The passed in time value is either a relative time in nanoseconds 4314 // or an absolute time in milliseconds. Either way it has to be unpacked 4315 // into suitable seconds and nanoseconds components and stored in the 4316 // given timespec structure. 4317 // Given time is a 64-bit value and the time_t used in the timespec is only 4318 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4319 // overflow if times way in the future are given. Further on Solaris versions 4320 // prior to 10 there is a restriction (see cond_timedwait) that the specified 4321 // number of seconds, in abstime, is less than current_time + 100,000,000. 4322 // As it will be 28 years before "now + 100000000" will overflow we can 4323 // ignore overflow and just impose a hard-limit on seconds using the value 4324 // of "now + 100,000,000". This places a limit on the timeout of about 3.17 4325 // years from "now". 4326 4327 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4328 assert(time > 0, "convertTime"); 4329 4330 struct timeval now; 4331 int status = gettimeofday(&now, NULL); 4332 assert(status == 0, "gettimeofday"); 4333 4334 time_t max_secs = now.tv_sec + MAX_SECS; 4335 4336 if (isAbsolute) { 4337 jlong secs = time / 1000; 4338 if (secs > max_secs) { 4339 absTime->tv_sec = max_secs; 4340 } else { 4341 absTime->tv_sec = secs; 4342 } 4343 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4344 } else { 4345 jlong secs = time / NANOSECS_PER_SEC; 4346 if (secs >= MAX_SECS) { 4347 absTime->tv_sec = max_secs; 4348 absTime->tv_nsec = 0; 4349 } else { 4350 absTime->tv_sec = now.tv_sec + secs; 4351 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4352 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4353 absTime->tv_nsec -= NANOSECS_PER_SEC; 4354 ++absTime->tv_sec; // note: this must be <= max_secs 4355 } 4356 } 4357 } 4358 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4359 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4360 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4361 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4362 } 4363 4364 void Parker::park(bool isAbsolute, jlong time) { 4365 // Ideally we'd do something useful while spinning, such 4366 // as calling unpackTime(). 4367 4368 // Optional fast-path check: 4369 // Return immediately if a permit is available. 4370 // We depend on Atomic::xchg() having full barrier semantics 4371 // since we are doing a lock-free update to _counter. 4372 if (Atomic::xchg(0, &_counter) > 0) return; 4373 4374 Thread* thread = Thread::current(); 4375 assert(thread->is_Java_thread(), "Must be JavaThread"); 4376 JavaThread *jt = (JavaThread *)thread; 4377 4378 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4379 // Check interrupt before trying to wait 4380 if (Thread::is_interrupted(thread, false)) { 4381 return; 4382 } 4383 4384 // Next, demultiplex/decode time arguments 4385 struct timespec absTime; 4386 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4387 return; 4388 } 4389 if (time > 0) { 4390 unpackTime(&absTime, isAbsolute, time); 4391 } 4392 4393 4394 // Enter safepoint region 4395 // Beware of deadlocks such as 6317397. 4396 // The per-thread Parker:: mutex is a classic leaf-lock. 4397 // In particular a thread must never block on the Threads_lock while 4398 // holding the Parker:: mutex. If safepoints are pending both the 4399 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4400 ThreadBlockInVM tbivm(jt); 4401 4402 // Don't wait if cannot get lock since interference arises from 4403 // unblocking. Also. check interrupt before trying wait 4404 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4405 return; 4406 } 4407 4408 int status; 4409 if (_counter > 0) { // no wait needed 4410 _counter = 0; 4411 status = pthread_mutex_unlock(_mutex); 4412 assert(status == 0, "invariant"); 4413 // Paranoia to ensure our locked and lock-free paths interact 4414 // correctly with each other and Java-level accesses. 4415 OrderAccess::fence(); 4416 return; 4417 } 4418 4419 #ifdef ASSERT 4420 // Don't catch signals while blocked; let the running threads have the signals. 4421 // (This allows a debugger to break into the running thread.) 4422 sigset_t oldsigs; 4423 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4424 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4425 #endif 4426 4427 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4428 jt->set_suspend_equivalent(); 4429 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4430 4431 if (time == 0) { 4432 status = pthread_cond_wait(_cond, _mutex); 4433 } else { 4434 status = pthread_cond_timedwait(_cond, _mutex, &absTime); 4435 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4436 pthread_cond_destroy(_cond); 4437 pthread_cond_init(_cond, NULL); 4438 } 4439 } 4440 assert_status(status == 0 || status == EINTR || 4441 status == ETIMEDOUT, 4442 status, "cond_timedwait"); 4443 4444 #ifdef ASSERT 4445 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4446 #endif 4447 4448 _counter = 0; 4449 status = pthread_mutex_unlock(_mutex); 4450 assert_status(status == 0, status, "invariant"); 4451 // Paranoia to ensure our locked and lock-free paths interact 4452 // correctly with each other and Java-level accesses. 4453 OrderAccess::fence(); 4454 4455 // If externally suspended while waiting, re-suspend 4456 if (jt->handle_special_suspend_equivalent_condition()) { 4457 jt->java_suspend_self(); 4458 } 4459 } 4460 4461 void Parker::unpark() { 4462 int status = pthread_mutex_lock(_mutex); 4463 assert(status == 0, "invariant"); 4464 const int s = _counter; 4465 _counter = 1; 4466 if (s < 1) { 4467 if (WorkAroundNPTLTimedWaitHang) { 4468 status = pthread_cond_signal(_cond); 4469 assert(status == 0, "invariant"); 4470 status = pthread_mutex_unlock(_mutex); 4471 assert(status == 0, "invariant"); 4472 } else { 4473 status = pthread_mutex_unlock(_mutex); 4474 assert(status == 0, "invariant"); 4475 status = pthread_cond_signal(_cond); 4476 assert(status == 0, "invariant"); 4477 } 4478 } else { 4479 pthread_mutex_unlock(_mutex); 4480 assert(status == 0, "invariant"); 4481 } 4482 } 4483 4484 4485 // Darwin has no "environ" in a dynamic library. 4486 #ifdef __APPLE__ 4487 #include <crt_externs.h> 4488 #define environ (*_NSGetEnviron()) 4489 #else 4490 extern char** environ; 4491 #endif 4492 4493 // Run the specified command in a separate process. Return its exit value, 4494 // or -1 on failure (e.g. can't fork a new process). 4495 // Unlike system(), this function can be called from signal handler. It 4496 // doesn't block SIGINT et al. 4497 int os::fork_and_exec(char* cmd) { 4498 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4499 4500 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4501 // pthread_atfork handlers and reset pthread library. All we need is a 4502 // separate process to execve. Make a direct syscall to fork process. 4503 // On IA64 there's no fork syscall, we have to use fork() and hope for 4504 // the best... 4505 pid_t pid = fork(); 4506 4507 if (pid < 0) { 4508 // fork failed 4509 return -1; 4510 4511 } else if (pid == 0) { 4512 // child process 4513 4514 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4515 // first to kill every thread on the thread list. Because this list is 4516 // not reset by fork() (see notes above), execve() will instead kill 4517 // every thread in the parent process. We know this is the only thread 4518 // in the new process, so make a system call directly. 4519 // IA64 should use normal execve() from glibc to match the glibc fork() 4520 // above. 4521 execve("/bin/sh", (char* const*)argv, environ); 4522 4523 // execve failed 4524 _exit(-1); 4525 4526 } else { 4527 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4528 // care about the actual exit code, for now. 4529 4530 int status; 4531 4532 // Wait for the child process to exit. This returns immediately if 4533 // the child has already exited. */ 4534 while (waitpid(pid, &status, 0) < 0) { 4535 switch (errno) { 4536 case ECHILD: return 0; 4537 case EINTR: break; 4538 default: return -1; 4539 } 4540 } 4541 4542 if (WIFEXITED(status)) { 4543 // The child exited normally; get its exit code. 4544 return WEXITSTATUS(status); 4545 } else if (WIFSIGNALED(status)) { 4546 // The child exited because of a signal 4547 // The best value to return is 0x80 + signal number, 4548 // because that is what all Unix shells do, and because 4549 // it allows callers to distinguish between process exit and 4550 // process death by signal. 4551 return 0x80 + WTERMSIG(status); 4552 } else { 4553 // Unknown exit code; pass it through 4554 return status; 4555 } 4556 } 4557 } 4558 4559 // is_headless_jre() 4560 // 4561 // Test for the existence of xawt/libmawt.so or libawt_xawt.so 4562 // in order to report if we are running in a headless jre 4563 // 4564 // Since JDK8 xawt/libmawt.so was moved into the same directory 4565 // as libawt.so, and renamed libawt_xawt.so 4566 // 4567 bool os::is_headless_jre() { 4568 #ifdef __APPLE__ 4569 // We no longer build headless-only on Mac OS X 4570 return false; 4571 #else 4572 struct stat statbuf; 4573 char buf[MAXPATHLEN]; 4574 char libmawtpath[MAXPATHLEN]; 4575 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4576 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4577 char *p; 4578 4579 // Get path to libjvm.so 4580 os::jvm_path(buf, sizeof(buf)); 4581 4582 // Get rid of libjvm.so 4583 p = strrchr(buf, '/'); 4584 if (p == NULL) { 4585 return false; 4586 } else { 4587 *p = '\0'; 4588 } 4589 4590 // Get rid of client or server 4591 p = strrchr(buf, '/'); 4592 if (p == NULL) { 4593 return false; 4594 } else { 4595 *p = '\0'; 4596 } 4597 4598 // check xawt/libmawt.so 4599 strcpy(libmawtpath, buf); 4600 strcat(libmawtpath, xawtstr); 4601 if (::stat(libmawtpath, &statbuf) == 0) return false; 4602 4603 // check libawt_xawt.so 4604 strcpy(libmawtpath, buf); 4605 strcat(libmawtpath, new_xawtstr); 4606 if (::stat(libmawtpath, &statbuf) == 0) return false; 4607 4608 return true; 4609 #endif 4610 } 4611 4612 // Get the default path to the core file 4613 // Returns the length of the string 4614 int os::get_core_path(char* buffer, size_t bufferSize) { 4615 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 4616 4617 // Truncate if theoretical string was longer than bufferSize 4618 n = MIN2(n, (int)bufferSize); 4619 4620 return n; 4621 } 4622 4623 #ifndef PRODUCT 4624 void TestReserveMemorySpecial_test() { 4625 // No tests available for this platform 4626 } 4627 #endif