1 /* 2 * Copyright (c) 1999, 2014, 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_share_bsd.hpp" 40 #include "prims/jniFastGetField.hpp" 41 #include "prims/jvm.h" 42 #include "prims/jvm_misc.hpp" 43 #include "runtime/arguments.hpp" 44 #include "runtime/atomic.inline.hpp" 45 #include "runtime/extendedPC.hpp" 46 #include "runtime/globals.hpp" 47 #include "runtime/interfaceSupport.hpp" 48 #include "runtime/java.hpp" 49 #include "runtime/javaCalls.hpp" 50 #include "runtime/mutexLocker.hpp" 51 #include "runtime/objectMonitor.hpp" 52 #include "runtime/orderAccess.inline.hpp" 53 #include "runtime/osThread.hpp" 54 #include "runtime/perfMemory.hpp" 55 #include "runtime/sharedRuntime.hpp" 56 #include "runtime/statSampler.hpp" 57 #include "runtime/stubRoutines.hpp" 58 #include "runtime/thread.inline.hpp" 59 #include "runtime/threadCritical.hpp" 60 #include "runtime/timer.hpp" 61 #include "services/attachListener.hpp" 62 #include "services/memTracker.hpp" 63 #include "services/runtimeService.hpp" 64 #include "utilities/decoder.hpp" 65 #include "utilities/defaultStream.hpp" 66 #include "utilities/events.hpp" 67 #include "utilities/growableArray.hpp" 68 #include "utilities/vmError.hpp" 69 70 // put OS-includes here 71 # include <sys/types.h> 72 # include <sys/mman.h> 73 # include <sys/stat.h> 74 # include <sys/select.h> 75 # include <pthread.h> 76 # include <signal.h> 77 # include <errno.h> 78 # include <dlfcn.h> 79 # include <stdio.h> 80 # include <unistd.h> 81 # include <sys/resource.h> 82 # include <pthread.h> 83 # include <sys/stat.h> 84 # include <sys/time.h> 85 # include <sys/times.h> 86 # include <sys/utsname.h> 87 # include <sys/socket.h> 88 # include <sys/wait.h> 89 # include <time.h> 90 # include <pwd.h> 91 # include <poll.h> 92 # include <semaphore.h> 93 # include <fcntl.h> 94 # include <string.h> 95 # include <sys/param.h> 96 # include <sys/sysctl.h> 97 # include <sys/ipc.h> 98 # include <sys/shm.h> 99 #ifndef __APPLE__ 100 # include <link.h> 101 #endif 102 # include <stdint.h> 103 # include <inttypes.h> 104 # include <sys/ioctl.h> 105 # include <sys/syscall.h> 106 107 #if defined(__FreeBSD__) || defined(__NetBSD__) 108 # include <elf.h> 109 #endif 110 111 #ifdef __APPLE__ 112 # include <mach/mach.h> // semaphore_* API 113 # include <mach-o/dyld.h> 114 # include <sys/proc_info.h> 115 # include <objc/objc-auto.h> 116 #endif 117 118 #ifndef MAP_ANONYMOUS 119 #define MAP_ANONYMOUS MAP_ANON 120 #endif 121 122 #define MAX_PATH (2 * K) 123 124 // for timer info max values which include all bits 125 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 126 127 #define LARGEPAGES_BIT (1 << 6) 128 129 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 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 //////////////////////////////////////////////////////////////////////////////// 193 // environment support 194 195 bool os::getenv(const char* name, char* buf, int len) { 196 const char* val = ::getenv(name); 197 if (val != NULL && strlen(val) < (size_t)len) { 198 strcpy(buf, val); 199 return true; 200 } 201 if (len > 0) buf[0] = 0; // return a null string 202 return false; 203 } 204 205 206 // Return true if user is running as root. 207 208 bool os::have_special_privileges() { 209 static bool init = false; 210 static bool privileges = false; 211 if (!init) { 212 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 213 init = true; 214 } 215 return privileges; 216 } 217 218 219 220 // Cpu architecture string 221 #if defined(ZERO) 222 static char cpu_arch[] = ZERO_LIBARCH; 223 #elif defined(IA64) 224 static char cpu_arch[] = "ia64"; 225 #elif defined(IA32) 226 static char cpu_arch[] = "i386"; 227 #elif defined(AMD64) 228 static char cpu_arch[] = "amd64"; 229 #elif defined(ARM) 230 static char cpu_arch[] = "arm"; 231 #elif defined(PPC32) 232 static char cpu_arch[] = "ppc"; 233 #elif defined(SPARC) 234 # ifdef _LP64 235 static char cpu_arch[] = "sparcv9"; 236 # else 237 static char cpu_arch[] = "sparc"; 238 # endif 239 #else 240 #error Add appropriate cpu_arch setting 241 #endif 242 243 // Compiler variant 244 #ifdef COMPILER2 245 #define COMPILER_VARIANT "server" 246 #else 247 #define COMPILER_VARIANT "client" 248 #endif 249 250 251 void os::Bsd::initialize_system_info() { 252 int mib[2]; 253 size_t len; 254 int cpu_val; 255 julong mem_val; 256 257 /* get processors count via hw.ncpus sysctl */ 258 mib[0] = CTL_HW; 259 mib[1] = HW_NCPU; 260 len = sizeof(cpu_val); 261 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 262 assert(len == sizeof(cpu_val), "unexpected data size"); 263 set_processor_count(cpu_val); 264 } 265 else { 266 set_processor_count(1); // fallback 267 } 268 269 /* get physical memory via hw.memsize sysctl (hw.memsize is used 270 * since it returns a 64 bit value) 271 */ 272 mib[0] = CTL_HW; 273 274 #if defined (HW_MEMSIZE) // Apple 275 mib[1] = HW_MEMSIZE; 276 #elif defined(HW_PHYSMEM) // Most of BSD 277 mib[1] = HW_PHYSMEM; 278 #elif defined(HW_REALMEM) // Old FreeBSD 279 mib[1] = HW_REALMEM; 280 #else 281 #error No ways to get physmem 282 #endif 283 284 len = sizeof(mem_val); 285 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 286 assert(len == sizeof(mem_val), "unexpected data size"); 287 _physical_memory = mem_val; 288 } else { 289 _physical_memory = 256*1024*1024; // fallback (XXXBSD?) 290 } 291 292 #ifdef __OpenBSD__ 293 { 294 // limit _physical_memory memory view on OpenBSD since 295 // datasize rlimit restricts us anyway. 296 struct rlimit limits; 297 getrlimit(RLIMIT_DATA, &limits); 298 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 299 } 300 #endif 301 } 302 303 #ifdef __APPLE__ 304 static const char *get_home() { 305 const char *home_dir = ::getenv("HOME"); 306 if ((home_dir == NULL) || (*home_dir == '\0')) { 307 struct passwd *passwd_info = getpwuid(geteuid()); 308 if (passwd_info != NULL) { 309 home_dir = passwd_info->pw_dir; 310 } 311 } 312 313 return home_dir; 314 } 315 #endif 316 317 void os::init_system_properties_values() { 318 // The next steps are taken in the product version: 319 // 320 // Obtain the JAVA_HOME value from the location of libjvm.so. 321 // This library should be located at: 322 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 323 // 324 // If "/jre/lib/" appears at the right place in the path, then we 325 // assume libjvm.so is installed in a JDK and we use this path. 326 // 327 // Otherwise exit with message: "Could not create the Java virtual machine." 328 // 329 // The following extra steps are taken in the debugging version: 330 // 331 // If "/jre/lib/" does NOT appear at the right place in the path 332 // instead of exit check for $JAVA_HOME environment variable. 333 // 334 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 335 // then we append a fake suffix "hotspot/libjvm.so" to this path so 336 // it looks like libjvm.so is installed there 337 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 338 // 339 // Otherwise exit. 340 // 341 // Important note: if the location of libjvm.so changes this 342 // code needs to be changed accordingly. 343 344 // See ld(1): 345 // The linker uses the following search paths to locate required 346 // shared libraries: 347 // 1: ... 348 // ... 349 // 7: The default directories, normally /lib and /usr/lib. 350 #ifndef DEFAULT_LIBPATH 351 #define DEFAULT_LIBPATH "/lib:/usr/lib" 352 #endif 353 354 // Base path of extensions installed on the system. 355 #define SYS_EXT_DIR "/usr/java/packages" 356 #define EXTENSIONS_DIR "/lib/ext" 357 #define ENDORSED_DIR "/lib/endorsed" 358 359 #ifndef __APPLE__ 360 361 // Buffer that fits several sprintfs. 362 // Note that the space for the colon and the trailing null are provided 363 // by the nulls included by the sizeof operator. 364 const size_t bufsize = 365 MAX3((size_t)MAXPATHLEN, // For dll_dir & friends. 366 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir 367 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir 368 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 369 370 // sysclasspath, java_home, dll_dir 371 { 372 char *pslash; 373 os::jvm_path(buf, bufsize); 374 375 // Found the full path to libjvm.so. 376 // Now cut the path to <java_home>/jre if we can. 377 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 378 pslash = strrchr(buf, '/'); 379 if (pslash != NULL) { 380 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 381 } 382 Arguments::set_dll_dir(buf); 383 384 if (pslash != NULL) { 385 pslash = strrchr(buf, '/'); 386 if (pslash != NULL) { 387 *pslash = '\0'; // Get rid of /<arch>. 388 pslash = strrchr(buf, '/'); 389 if (pslash != NULL) { 390 *pslash = '\0'; // Get rid of /lib. 391 } 392 } 393 } 394 Arguments::set_java_home(buf); 395 set_boot_path('/', ':'); 396 } 397 398 // Where to look for native libraries. 399 // 400 // Note: Due to a legacy implementation, most of the library path 401 // is set in the launcher. This was to accomodate linking restrictions 402 // on legacy Bsd implementations (which are no longer supported). 403 // Eventually, all the library path setting will be done here. 404 // 405 // However, to prevent the proliferation of improperly built native 406 // libraries, the new path component /usr/java/packages is added here. 407 // Eventually, all the library path setting will be done here. 408 { 409 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 410 // should always exist (until the legacy problem cited above is 411 // addressed). 412 const char *v = ::getenv("LD_LIBRARY_PATH"); 413 const char *v_colon = ":"; 414 if (v == NULL) { v = ""; v_colon = ""; } 415 // That's +1 for the colon and +1 for the trailing '\0'. 416 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 417 strlen(v) + 1 + 418 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 419 mtInternal); 420 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 421 Arguments::set_library_path(ld_library_path); 422 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); 423 } 424 425 // Extensions directories. 426 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 427 Arguments::set_ext_dirs(buf); 428 429 // Endorsed standards default directory. 430 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 431 Arguments::set_endorsed_dirs(buf); 432 433 FREE_C_HEAP_ARRAY(char, buf, mtInternal); 434 435 #else // __APPLE__ 436 437 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 438 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 439 440 const char *user_home_dir = get_home(); 441 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 442 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 443 sizeof(SYS_EXTENSIONS_DIRS); 444 445 // Buffer that fits several sprintfs. 446 // Note that the space for the colon and the trailing null are provided 447 // by the nulls included by the sizeof operator. 448 const size_t bufsize = 449 MAX3((size_t)MAXPATHLEN, // for dll_dir & friends. 450 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir 451 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir 452 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 453 454 // sysclasspath, java_home, dll_dir 455 { 456 char *pslash; 457 os::jvm_path(buf, bufsize); 458 459 // Found the full path to libjvm.so. 460 // Now cut the path to <java_home>/jre if we can. 461 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 462 pslash = strrchr(buf, '/'); 463 if (pslash != NULL) { 464 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 465 } 466 Arguments::set_dll_dir(buf); 467 468 if (pslash != NULL) { 469 pslash = strrchr(buf, '/'); 470 if (pslash != NULL) { 471 *pslash = '\0'; // Get rid of /lib. 472 } 473 } 474 Arguments::set_java_home(buf); 475 set_boot_path('/', ':'); 476 } 477 478 // Where to look for native libraries. 479 // 480 // Note: Due to a legacy implementation, most of the library path 481 // is set in the launcher. This was to accomodate linking restrictions 482 // on legacy Bsd implementations (which are no longer supported). 483 // Eventually, all the library path setting will be done here. 484 // 485 // However, to prevent the proliferation of improperly built native 486 // libraries, the new path component /usr/java/packages is added here. 487 // Eventually, all the library path setting will be done here. 488 { 489 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 490 // should always exist (until the legacy problem cited above is 491 // addressed). 492 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 493 // can specify a directory inside an app wrapper 494 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 495 const char *l_colon = ":"; 496 if (l == NULL) { l = ""; l_colon = ""; } 497 498 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 499 const char *v_colon = ":"; 500 if (v == NULL) { v = ""; v_colon = ""; } 501 502 // Apple's Java6 has "." at the beginning of java.library.path. 503 // OpenJDK on Windows has "." at the end of java.library.path. 504 // OpenJDK on Linux and Solaris don't have "." in java.library.path 505 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 506 // "." is appended to the end of java.library.path. Yes, this 507 // could cause a change in behavior, but Apple's Java6 behavior 508 // can be achieved by putting "." at the beginning of the 509 // JAVA_LIBRARY_PATH environment variable. 510 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 511 strlen(v) + 1 + strlen(l) + 1 + 512 system_ext_size + 3, 513 mtInternal); 514 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 515 v, v_colon, l, l_colon, user_home_dir); 516 Arguments::set_library_path(ld_library_path); 517 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); 518 } 519 520 // Extensions directories. 521 // 522 // Note that the space for the colon and the trailing null are provided 523 // by the nulls included by the sizeof operator (so actually one byte more 524 // than necessary is allocated). 525 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 526 user_home_dir, Arguments::get_java_home()); 527 Arguments::set_ext_dirs(buf); 528 529 // Endorsed standards default directory. 530 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 531 Arguments::set_endorsed_dirs(buf); 532 533 FREE_C_HEAP_ARRAY(char, buf, mtInternal); 534 535 #undef SYS_EXTENSIONS_DIR 536 #undef SYS_EXTENSIONS_DIRS 537 538 #endif // __APPLE__ 539 540 #undef SYS_EXT_DIR 541 #undef EXTENSIONS_DIR 542 #undef ENDORSED_DIR 543 } 544 545 //////////////////////////////////////////////////////////////////////////////// 546 // breakpoint support 547 548 void os::breakpoint() { 549 BREAKPOINT; 550 } 551 552 extern "C" void breakpoint() { 553 // use debugger to set breakpoint here 554 } 555 556 //////////////////////////////////////////////////////////////////////////////// 557 // signal support 558 559 debug_only(static bool signal_sets_initialized = false); 560 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 561 562 bool os::Bsd::is_sig_ignored(int sig) { 563 struct sigaction oact; 564 sigaction(sig, (struct sigaction*)NULL, &oact); 565 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 566 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 567 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 568 return true; 569 else 570 return false; 571 } 572 573 void os::Bsd::signal_sets_init() { 574 // Should also have an assertion stating we are still single-threaded. 575 assert(!signal_sets_initialized, "Already initialized"); 576 // Fill in signals that are necessarily unblocked for all threads in 577 // the VM. Currently, we unblock the following signals: 578 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 579 // by -Xrs (=ReduceSignalUsage)); 580 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 581 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 582 // the dispositions or masks wrt these signals. 583 // Programs embedding the VM that want to use the above signals for their 584 // own purposes must, at this time, use the "-Xrs" option to prevent 585 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 586 // (See bug 4345157, and other related bugs). 587 // In reality, though, unblocking these signals is really a nop, since 588 // these signals are not blocked by default. 589 sigemptyset(&unblocked_sigs); 590 sigemptyset(&allowdebug_blocked_sigs); 591 sigaddset(&unblocked_sigs, SIGILL); 592 sigaddset(&unblocked_sigs, SIGSEGV); 593 sigaddset(&unblocked_sigs, SIGBUS); 594 sigaddset(&unblocked_sigs, SIGFPE); 595 sigaddset(&unblocked_sigs, SR_signum); 596 597 if (!ReduceSignalUsage) { 598 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 599 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 600 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 601 } 602 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 603 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 604 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 605 } 606 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 607 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 608 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 609 } 610 } 611 // Fill in signals that are blocked by all but the VM thread. 612 sigemptyset(&vm_sigs); 613 if (!ReduceSignalUsage) 614 sigaddset(&vm_sigs, BREAK_SIGNAL); 615 debug_only(signal_sets_initialized = true); 616 617 } 618 619 // These are signals that are unblocked while a thread is running Java. 620 // (For some reason, they get blocked by default.) 621 sigset_t* os::Bsd::unblocked_signals() { 622 assert(signal_sets_initialized, "Not initialized"); 623 return &unblocked_sigs; 624 } 625 626 // These are the signals that are blocked while a (non-VM) thread is 627 // running Java. Only the VM thread handles these signals. 628 sigset_t* os::Bsd::vm_signals() { 629 assert(signal_sets_initialized, "Not initialized"); 630 return &vm_sigs; 631 } 632 633 // These are signals that are blocked during cond_wait to allow debugger in 634 sigset_t* os::Bsd::allowdebug_blocked_signals() { 635 assert(signal_sets_initialized, "Not initialized"); 636 return &allowdebug_blocked_sigs; 637 } 638 639 void os::Bsd::hotspot_sigmask(Thread* thread) { 640 641 //Save caller's signal mask before setting VM signal mask 642 sigset_t caller_sigmask; 643 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 644 645 OSThread* osthread = thread->osthread(); 646 osthread->set_caller_sigmask(caller_sigmask); 647 648 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 649 650 if (!ReduceSignalUsage) { 651 if (thread->is_VM_thread()) { 652 // Only the VM thread handles BREAK_SIGNAL ... 653 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 654 } else { 655 // ... all other threads block BREAK_SIGNAL 656 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 657 } 658 } 659 } 660 661 662 ////////////////////////////////////////////////////////////////////////////// 663 // create new thread 664 665 // check if it's safe to start a new thread 666 static bool _thread_safety_check(Thread* thread) { 667 return true; 668 } 669 670 #ifdef __APPLE__ 671 // library handle for calling objc_registerThreadWithCollector() 672 // without static linking to the libobjc library 673 #define OBJC_LIB "/usr/lib/libobjc.dylib" 674 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 675 typedef void (*objc_registerThreadWithCollector_t)(); 676 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 677 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 678 #endif 679 680 #ifdef __APPLE__ 681 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 682 // Additional thread_id used to correlate threads in SA 683 thread_identifier_info_data_t m_ident_info; 684 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 685 686 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 687 (thread_info_t) &m_ident_info, &count); 688 689 return m_ident_info.thread_id; 690 } 691 #endif 692 693 // Thread start routine for all newly created threads 694 static void *java_start(Thread *thread) { 695 // Try to randomize the cache line index of hot stack frames. 696 // This helps when threads of the same stack traces evict each other's 697 // cache lines. The threads can be either from the same JVM instance, or 698 // from different JVM instances. The benefit is especially true for 699 // processors with hyperthreading technology. 700 static int counter = 0; 701 int pid = os::current_process_id(); 702 alloca(((pid ^ counter++) & 7) * 128); 703 704 ThreadLocalStorage::set_thread(thread); 705 706 OSThread* osthread = thread->osthread(); 707 Monitor* sync = osthread->startThread_lock(); 708 709 // non floating stack BsdThreads needs extra check, see above 710 if (!_thread_safety_check(thread)) { 711 // notify parent thread 712 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 713 osthread->set_state(ZOMBIE); 714 sync->notify_all(); 715 return NULL; 716 } 717 718 osthread->set_thread_id(os::Bsd::gettid()); 719 720 #ifdef __APPLE__ 721 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 722 guarantee(unique_thread_id != 0, "unique thread id was not found"); 723 osthread->set_unique_thread_id(unique_thread_id); 724 #endif 725 // initialize signal mask for this thread 726 os::Bsd::hotspot_sigmask(thread); 727 728 // initialize floating point control register 729 os::Bsd::init_thread_fpu_state(); 730 731 #ifdef __APPLE__ 732 // register thread with objc gc 733 if (objc_registerThreadWithCollectorFunction != NULL) { 734 objc_registerThreadWithCollectorFunction(); 735 } 736 #endif 737 738 // handshaking with parent thread 739 { 740 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 741 742 // notify parent thread 743 osthread->set_state(INITIALIZED); 744 sync->notify_all(); 745 746 // wait until os::start_thread() 747 while (osthread->get_state() == INITIALIZED) { 748 sync->wait(Mutex::_no_safepoint_check_flag); 749 } 750 } 751 752 // call one more level start routine 753 thread->run(); 754 755 return 0; 756 } 757 758 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 759 assert(thread->osthread() == NULL, "caller responsible"); 760 761 // Allocate the OSThread object 762 OSThread* osthread = new OSThread(NULL, NULL); 763 if (osthread == NULL) { 764 return false; 765 } 766 767 // set the correct thread state 768 osthread->set_thread_type(thr_type); 769 770 // Initial state is ALLOCATED but not INITIALIZED 771 osthread->set_state(ALLOCATED); 772 773 thread->set_osthread(osthread); 774 775 // init thread attributes 776 pthread_attr_t attr; 777 pthread_attr_init(&attr); 778 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 779 780 // stack size 781 if (os::Bsd::supports_variable_stack_size()) { 782 // calculate stack size if it's not specified by caller 783 if (stack_size == 0) { 784 stack_size = os::Bsd::default_stack_size(thr_type); 785 786 switch (thr_type) { 787 case os::java_thread: 788 // Java threads use ThreadStackSize which default value can be 789 // changed with the flag -Xss 790 assert(JavaThread::stack_size_at_create() > 0, "this should be set"); 791 stack_size = JavaThread::stack_size_at_create(); 792 break; 793 case os::compiler_thread: 794 if (CompilerThreadStackSize > 0) { 795 stack_size = (size_t)(CompilerThreadStackSize * K); 796 break; 797 } // else fall through: 798 // use VMThreadStackSize if CompilerThreadStackSize is not defined 799 case os::vm_thread: 800 case os::pgc_thread: 801 case os::cgc_thread: 802 case os::watcher_thread: 803 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 804 break; 805 } 806 } 807 808 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 809 pthread_attr_setstacksize(&attr, stack_size); 810 } else { 811 // let pthread_create() pick the default value. 812 } 813 814 ThreadState state; 815 816 { 817 pthread_t tid; 818 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 819 820 pthread_attr_destroy(&attr); 821 822 if (ret != 0) { 823 if (PrintMiscellaneous && (Verbose || WizardMode)) { 824 perror("pthread_create()"); 825 } 826 // Need to clean up stuff we've allocated so far 827 thread->set_osthread(NULL); 828 delete osthread; 829 return false; 830 } 831 832 // Store pthread info into the OSThread 833 osthread->set_pthread_id(tid); 834 835 // Wait until child thread is either initialized or aborted 836 { 837 Monitor* sync_with_child = osthread->startThread_lock(); 838 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 839 while ((state = osthread->get_state()) == ALLOCATED) { 840 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 841 } 842 } 843 844 } 845 846 // Aborted due to thread limit being reached 847 if (state == ZOMBIE) { 848 thread->set_osthread(NULL); 849 delete osthread; 850 return false; 851 } 852 853 // The thread is returned suspended (in state INITIALIZED), 854 // and is started higher up in the call chain 855 assert(state == INITIALIZED, "race condition"); 856 return true; 857 } 858 859 ///////////////////////////////////////////////////////////////////////////// 860 // attach existing thread 861 862 // bootstrap the main thread 863 bool os::create_main_thread(JavaThread* thread) { 864 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 865 return create_attached_thread(thread); 866 } 867 868 bool os::create_attached_thread(JavaThread* thread) { 869 #ifdef ASSERT 870 thread->verify_not_published(); 871 #endif 872 873 // Allocate the OSThread object 874 OSThread* osthread = new OSThread(NULL, NULL); 875 876 if (osthread == NULL) { 877 return false; 878 } 879 880 osthread->set_thread_id(os::Bsd::gettid()); 881 882 // Store pthread info into the OSThread 883 #ifdef __APPLE__ 884 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 885 guarantee(unique_thread_id != 0, "just checking"); 886 osthread->set_unique_thread_id(unique_thread_id); 887 #endif 888 osthread->set_pthread_id(::pthread_self()); 889 890 // initialize floating point control register 891 os::Bsd::init_thread_fpu_state(); 892 893 // Initial thread state is RUNNABLE 894 osthread->set_state(RUNNABLE); 895 896 thread->set_osthread(osthread); 897 898 // initialize signal mask for this thread 899 // and save the caller's signal mask 900 os::Bsd::hotspot_sigmask(thread); 901 902 return true; 903 } 904 905 void os::pd_start_thread(Thread* thread) { 906 OSThread * osthread = thread->osthread(); 907 assert(osthread->get_state() != INITIALIZED, "just checking"); 908 Monitor* sync_with_child = osthread->startThread_lock(); 909 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 910 sync_with_child->notify(); 911 } 912 913 // Free Bsd resources related to the OSThread 914 void os::free_thread(OSThread* osthread) { 915 assert(osthread != NULL, "osthread not set"); 916 917 if (Thread::current()->osthread() == osthread) { 918 // Restore caller's signal mask 919 sigset_t sigmask = osthread->caller_sigmask(); 920 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 921 } 922 923 delete osthread; 924 } 925 926 ////////////////////////////////////////////////////////////////////////////// 927 // thread local storage 928 929 // Restore the thread pointer if the destructor is called. This is in case 930 // someone from JNI code sets up a destructor with pthread_key_create to run 931 // detachCurrentThread on thread death. Unless we restore the thread pointer we 932 // will hang or crash. When detachCurrentThread is called the key will be set 933 // to null and we will not be called again. If detachCurrentThread is never 934 // called we could loop forever depending on the pthread implementation. 935 static void restore_thread_pointer(void* p) { 936 Thread* thread = (Thread*) p; 937 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread); 938 } 939 940 int os::allocate_thread_local_storage() { 941 pthread_key_t key; 942 int rslt = pthread_key_create(&key, restore_thread_pointer); 943 assert(rslt == 0, "cannot allocate thread local storage"); 944 return (int)key; 945 } 946 947 // Note: This is currently not used by VM, as we don't destroy TLS key 948 // on VM exit. 949 void os::free_thread_local_storage(int index) { 950 int rslt = pthread_key_delete((pthread_key_t)index); 951 assert(rslt == 0, "invalid index"); 952 } 953 954 void os::thread_local_storage_at_put(int index, void* value) { 955 int rslt = pthread_setspecific((pthread_key_t)index, value); 956 assert(rslt == 0, "pthread_setspecific failed"); 957 } 958 959 extern "C" Thread* get_thread() { 960 return ThreadLocalStorage::thread(); 961 } 962 963 964 //////////////////////////////////////////////////////////////////////////////// 965 // time support 966 967 // Time since start-up in seconds to a fine granularity. 968 // Used by VMSelfDestructTimer and the MemProfiler. 969 double os::elapsedTime() { 970 971 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 972 } 973 974 jlong os::elapsed_counter() { 975 return javaTimeNanos() - initial_time_count; 976 } 977 978 jlong os::elapsed_frequency() { 979 return NANOSECS_PER_SEC; // nanosecond resolution 980 } 981 982 bool os::supports_vtime() { return true; } 983 bool os::enable_vtime() { return false; } 984 bool os::vtime_enabled() { return false; } 985 986 double os::elapsedVTime() { 987 // better than nothing, but not much 988 return elapsedTime(); 989 } 990 991 jlong os::javaTimeMillis() { 992 timeval time; 993 int status = gettimeofday(&time, NULL); 994 assert(status != -1, "bsd error"); 995 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 996 } 997 998 #ifndef __APPLE__ 999 #ifndef CLOCK_MONOTONIC 1000 #define CLOCK_MONOTONIC (1) 1001 #endif 1002 #endif 1003 1004 #ifdef __APPLE__ 1005 void os::Bsd::clock_init() { 1006 mach_timebase_info(&_timebase_info); 1007 } 1008 #else 1009 void os::Bsd::clock_init() { 1010 struct timespec res; 1011 struct timespec tp; 1012 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 1013 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 1014 // yes, monotonic clock is supported 1015 _clock_gettime = ::clock_gettime; 1016 } 1017 } 1018 #endif 1019 1020 1021 1022 #ifdef __APPLE__ 1023 1024 jlong os::javaTimeNanos() { 1025 const uint64_t tm = mach_absolute_time(); 1026 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 1027 const uint64_t prev = Bsd::_max_abstime; 1028 if (now <= prev) { 1029 return prev; // same or retrograde time; 1030 } 1031 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 1032 assert(obsv >= prev, "invariant"); // Monotonicity 1033 // If the CAS succeeded then we're done and return "now". 1034 // If the CAS failed and the observed value "obsv" is >= now then 1035 // we should return "obsv". If the CAS failed and now > obsv > prv then 1036 // some other thread raced this thread and installed a new value, in which case 1037 // we could either (a) retry the entire operation, (b) retry trying to install now 1038 // or (c) just return obsv. We use (c). No loop is required although in some cases 1039 // we might discard a higher "now" value in deference to a slightly lower but freshly 1040 // installed obsv value. That's entirely benign -- it admits no new orderings compared 1041 // to (a) or (b) -- and greatly reduces coherence traffic. 1042 // We might also condition (c) on the magnitude of the delta between obsv and now. 1043 // Avoiding excessive CAS operations to hot RW locations is critical. 1044 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 1045 return (prev == obsv) ? now : obsv; 1046 } 1047 1048 #else // __APPLE__ 1049 1050 jlong os::javaTimeNanos() { 1051 if (os::supports_monotonic_clock()) { 1052 struct timespec tp; 1053 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 1054 assert(status == 0, "gettime error"); 1055 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1056 return result; 1057 } else { 1058 timeval time; 1059 int status = gettimeofday(&time, NULL); 1060 assert(status != -1, "bsd error"); 1061 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1062 return 1000 * usecs; 1063 } 1064 } 1065 1066 #endif // __APPLE__ 1067 1068 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1069 if (os::supports_monotonic_clock()) { 1070 info_ptr->max_value = ALL_64_BITS; 1071 1072 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1073 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1074 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1075 } else { 1076 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1077 info_ptr->max_value = ALL_64_BITS; 1078 1079 // gettimeofday is a real time clock so it skips 1080 info_ptr->may_skip_backward = true; 1081 info_ptr->may_skip_forward = true; 1082 } 1083 1084 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1085 } 1086 1087 // Return the real, user, and system times in seconds from an 1088 // arbitrary fixed point in the past. 1089 bool os::getTimesSecs(double* process_real_time, 1090 double* process_user_time, 1091 double* process_system_time) { 1092 struct tms ticks; 1093 clock_t real_ticks = times(&ticks); 1094 1095 if (real_ticks == (clock_t) (-1)) { 1096 return false; 1097 } else { 1098 double ticks_per_second = (double) clock_tics_per_sec; 1099 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1100 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1101 *process_real_time = ((double) real_ticks) / ticks_per_second; 1102 1103 return true; 1104 } 1105 } 1106 1107 1108 char * os::local_time_string(char *buf, size_t buflen) { 1109 struct tm t; 1110 time_t long_time; 1111 time(&long_time); 1112 localtime_r(&long_time, &t); 1113 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1114 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1115 t.tm_hour, t.tm_min, t.tm_sec); 1116 return buf; 1117 } 1118 1119 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1120 return localtime_r(clock, res); 1121 } 1122 1123 //////////////////////////////////////////////////////////////////////////////// 1124 // runtime exit support 1125 1126 // Note: os::shutdown() might be called very early during initialization, or 1127 // called from signal handler. Before adding something to os::shutdown(), make 1128 // sure it is async-safe and can handle partially initialized VM. 1129 void os::shutdown() { 1130 1131 // allow PerfMemory to attempt cleanup of any persistent resources 1132 perfMemory_exit(); 1133 1134 // needs to remove object in file system 1135 AttachListener::abort(); 1136 1137 // flush buffered output, finish log files 1138 ostream_abort(); 1139 1140 // Check for abort hook 1141 abort_hook_t abort_hook = Arguments::abort_hook(); 1142 if (abort_hook != NULL) { 1143 abort_hook(); 1144 } 1145 1146 } 1147 1148 // Note: os::abort() might be called very early during initialization, or 1149 // called from signal handler. Before adding something to os::abort(), make 1150 // sure it is async-safe and can handle partially initialized VM. 1151 void os::abort(bool dump_core) { 1152 os::shutdown(); 1153 if (dump_core) { 1154 #ifndef PRODUCT 1155 fdStream out(defaultStream::output_fd()); 1156 out.print_raw("Current thread is "); 1157 char buf[16]; 1158 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1159 out.print_raw_cr(buf); 1160 out.print_raw_cr("Dumping core ..."); 1161 #endif 1162 ::abort(); // dump core 1163 } 1164 1165 ::exit(1); 1166 } 1167 1168 // Die immediately, no exit hook, no abort hook, no cleanup. 1169 void os::die() { 1170 // _exit() on BsdThreads only kills current thread 1171 ::abort(); 1172 } 1173 1174 // unused on bsd for now. 1175 void os::set_error_file(const char *logfile) {} 1176 1177 1178 // This method is a copy of JDK's sysGetLastErrorString 1179 // from src/solaris/hpi/src/system_md.c 1180 1181 size_t os::lasterror(char *buf, size_t len) { 1182 1183 if (errno == 0) return 0; 1184 1185 const char *s = ::strerror(errno); 1186 size_t n = ::strlen(s); 1187 if (n >= len) { 1188 n = len - 1; 1189 } 1190 ::strncpy(buf, s, n); 1191 buf[n] = '\0'; 1192 return n; 1193 } 1194 1195 // Information of current thread in variety of formats 1196 pid_t os::Bsd::gettid() { 1197 int retval = -1; 1198 1199 #ifdef __APPLE__ //XNU kernel 1200 // despite the fact mach port is actually not a thread id use it 1201 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1202 retval = ::pthread_mach_thread_np(::pthread_self()); 1203 guarantee(retval != 0, "just checking"); 1204 return retval; 1205 1206 #elif __FreeBSD__ 1207 retval = syscall(SYS_thr_self); 1208 #elif __OpenBSD__ 1209 retval = syscall(SYS_getthrid); 1210 #elif __NetBSD__ 1211 retval = (pid_t) syscall(SYS__lwp_self); 1212 #endif 1213 1214 if (retval == -1) { 1215 return getpid(); 1216 } 1217 } 1218 1219 intx os::current_thread_id() { 1220 #ifdef __APPLE__ 1221 return (intx)::pthread_mach_thread_np(::pthread_self()); 1222 #else 1223 return (intx)::pthread_self(); 1224 #endif 1225 } 1226 1227 int os::current_process_id() { 1228 1229 // Under the old bsd thread library, bsd gives each thread 1230 // its own process id. Because of this each thread will return 1231 // a different pid if this method were to return the result 1232 // of getpid(2). Bsd provides no api that returns the pid 1233 // of the launcher thread for the vm. This implementation 1234 // returns a unique pid, the pid of the launcher thread 1235 // that starts the vm 'process'. 1236 1237 // Under the NPTL, getpid() returns the same pid as the 1238 // launcher thread rather than a unique pid per thread. 1239 // Use gettid() if you want the old pre NPTL behaviour. 1240 1241 // if you are looking for the result of a call to getpid() that 1242 // returns a unique pid for the calling thread, then look at the 1243 // OSThread::thread_id() method in osThread_bsd.hpp file 1244 1245 return (int)(_initial_pid ? _initial_pid : getpid()); 1246 } 1247 1248 // DLL functions 1249 1250 #define JNI_LIB_PREFIX "lib" 1251 #ifdef __APPLE__ 1252 #define JNI_LIB_SUFFIX ".dylib" 1253 #else 1254 #define JNI_LIB_SUFFIX ".so" 1255 #endif 1256 1257 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1258 1259 // This must be hard coded because it's the system's temporary 1260 // directory not the java application's temp directory, ala java.io.tmpdir. 1261 #ifdef __APPLE__ 1262 // macosx has a secure per-user temporary directory 1263 char temp_path_storage[PATH_MAX]; 1264 const char* os::get_temp_directory() { 1265 static char *temp_path = NULL; 1266 if (temp_path == NULL) { 1267 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1268 if (pathSize == 0 || pathSize > PATH_MAX) { 1269 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1270 } 1271 temp_path = temp_path_storage; 1272 } 1273 return temp_path; 1274 } 1275 #else /* __APPLE__ */ 1276 const char* os::get_temp_directory() { return "/tmp"; } 1277 #endif /* __APPLE__ */ 1278 1279 static bool file_exists(const char* filename) { 1280 struct stat statbuf; 1281 if (filename == NULL || strlen(filename) == 0) { 1282 return false; 1283 } 1284 return os::stat(filename, &statbuf) == 0; 1285 } 1286 1287 bool os::dll_build_name(char* buffer, size_t buflen, 1288 const char* pname, const char* fname) { 1289 bool retval = false; 1290 // Copied from libhpi 1291 const size_t pnamelen = pname ? strlen(pname) : 0; 1292 1293 // Return error on buffer overflow. 1294 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1295 return retval; 1296 } 1297 1298 if (pnamelen == 0) { 1299 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1300 retval = true; 1301 } else if (strchr(pname, *os::path_separator()) != NULL) { 1302 int n; 1303 char** pelements = split_path(pname, &n); 1304 if (pelements == NULL) { 1305 return false; 1306 } 1307 for (int i = 0; i < n; i++) { 1308 // Really shouldn't be NULL, but check can't hurt 1309 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1310 continue; // skip the empty path values 1311 } 1312 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1313 pelements[i], fname); 1314 if (file_exists(buffer)) { 1315 retval = true; 1316 break; 1317 } 1318 } 1319 // release the storage 1320 for (int i = 0; i < n; i++) { 1321 if (pelements[i] != NULL) { 1322 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1323 } 1324 } 1325 if (pelements != NULL) { 1326 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1327 } 1328 } else { 1329 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1330 retval = true; 1331 } 1332 return retval; 1333 } 1334 1335 // check if addr is inside libjvm.so 1336 bool os::address_is_in_vm(address addr) { 1337 static address libjvm_base_addr; 1338 Dl_info dlinfo; 1339 1340 if (libjvm_base_addr == NULL) { 1341 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1342 libjvm_base_addr = (address)dlinfo.dli_fbase; 1343 } 1344 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1345 } 1346 1347 if (dladdr((void *)addr, &dlinfo) != 0) { 1348 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1349 } 1350 1351 return false; 1352 } 1353 1354 1355 #define MACH_MAXSYMLEN 256 1356 1357 bool os::dll_address_to_function_name(address addr, char *buf, 1358 int buflen, int *offset) { 1359 // buf is not optional, but offset is optional 1360 assert(buf != NULL, "sanity check"); 1361 1362 Dl_info dlinfo; 1363 char localbuf[MACH_MAXSYMLEN]; 1364 1365 if (dladdr((void*)addr, &dlinfo) != 0) { 1366 // see if we have a matching symbol 1367 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1368 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1369 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1370 } 1371 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1372 return true; 1373 } 1374 // no matching symbol so try for just file info 1375 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1376 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1377 buf, buflen, offset, dlinfo.dli_fname)) { 1378 return true; 1379 } 1380 } 1381 1382 // Handle non-dynamic manually: 1383 if (dlinfo.dli_fbase != NULL && 1384 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1385 dlinfo.dli_fbase)) { 1386 if (!Decoder::demangle(localbuf, buf, buflen)) { 1387 jio_snprintf(buf, buflen, "%s", localbuf); 1388 } 1389 return true; 1390 } 1391 } 1392 buf[0] = '\0'; 1393 if (offset != NULL) *offset = -1; 1394 return false; 1395 } 1396 1397 // ported from solaris version 1398 bool os::dll_address_to_library_name(address addr, char* buf, 1399 int buflen, int* offset) { 1400 // buf is not optional, but offset is optional 1401 assert(buf != NULL, "sanity check"); 1402 1403 Dl_info dlinfo; 1404 1405 if (dladdr((void*)addr, &dlinfo) != 0) { 1406 if (dlinfo.dli_fname != NULL) { 1407 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1408 } 1409 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1410 *offset = addr - (address)dlinfo.dli_fbase; 1411 } 1412 return true; 1413 } 1414 1415 buf[0] = '\0'; 1416 if (offset) *offset = -1; 1417 return false; 1418 } 1419 1420 // Loads .dll/.so and 1421 // in case of error it checks if .dll/.so was built for the 1422 // same architecture as Hotspot is running on 1423 1424 #ifdef __APPLE__ 1425 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1426 void * result= ::dlopen(filename, RTLD_LAZY); 1427 if (result != NULL) { 1428 // Successful loading 1429 return result; 1430 } 1431 1432 // Read system error message into ebuf 1433 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1434 ebuf[ebuflen-1]='\0'; 1435 1436 return NULL; 1437 } 1438 #else 1439 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1440 { 1441 void * result= ::dlopen(filename, RTLD_LAZY); 1442 if (result != NULL) { 1443 // Successful loading 1444 return result; 1445 } 1446 1447 Elf32_Ehdr elf_head; 1448 1449 // Read system error message into ebuf 1450 // It may or may not be overwritten below 1451 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1452 ebuf[ebuflen-1]='\0'; 1453 int diag_msg_max_length=ebuflen-strlen(ebuf); 1454 char* diag_msg_buf=ebuf+strlen(ebuf); 1455 1456 if (diag_msg_max_length==0) { 1457 // No more space in ebuf for additional diagnostics message 1458 return NULL; 1459 } 1460 1461 1462 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1463 1464 if (file_descriptor < 0) { 1465 // Can't open library, report dlerror() message 1466 return NULL; 1467 } 1468 1469 bool failed_to_read_elf_head= 1470 (sizeof(elf_head)!= 1471 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1472 1473 ::close(file_descriptor); 1474 if (failed_to_read_elf_head) { 1475 // file i/o error - report dlerror() msg 1476 return NULL; 1477 } 1478 1479 typedef struct { 1480 Elf32_Half code; // Actual value as defined in elf.h 1481 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1482 char elf_class; // 32 or 64 bit 1483 char endianess; // MSB or LSB 1484 char* name; // String representation 1485 } arch_t; 1486 1487 #ifndef EM_486 1488 #define EM_486 6 /* Intel 80486 */ 1489 #endif 1490 1491 #ifndef EM_MIPS_RS3_LE 1492 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1493 #endif 1494 1495 #ifndef EM_PPC64 1496 #define EM_PPC64 21 /* PowerPC64 */ 1497 #endif 1498 1499 #ifndef EM_S390 1500 #define EM_S390 22 /* IBM System/390 */ 1501 #endif 1502 1503 #ifndef EM_IA_64 1504 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1505 #endif 1506 1507 #ifndef EM_X86_64 1508 #define EM_X86_64 62 /* AMD x86-64 */ 1509 #endif 1510 1511 static const arch_t arch_array[]={ 1512 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1513 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1514 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1515 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1516 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1517 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1518 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1519 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1520 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1521 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1522 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1523 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1524 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1525 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1526 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1527 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1528 }; 1529 1530 #if (defined IA32) 1531 static Elf32_Half running_arch_code=EM_386; 1532 #elif (defined AMD64) 1533 static Elf32_Half running_arch_code=EM_X86_64; 1534 #elif (defined IA64) 1535 static Elf32_Half running_arch_code=EM_IA_64; 1536 #elif (defined __sparc) && (defined _LP64) 1537 static Elf32_Half running_arch_code=EM_SPARCV9; 1538 #elif (defined __sparc) && (!defined _LP64) 1539 static Elf32_Half running_arch_code=EM_SPARC; 1540 #elif (defined __powerpc64__) 1541 static Elf32_Half running_arch_code=EM_PPC64; 1542 #elif (defined __powerpc__) 1543 static Elf32_Half running_arch_code=EM_PPC; 1544 #elif (defined ARM) 1545 static Elf32_Half running_arch_code=EM_ARM; 1546 #elif (defined S390) 1547 static Elf32_Half running_arch_code=EM_S390; 1548 #elif (defined ALPHA) 1549 static Elf32_Half running_arch_code=EM_ALPHA; 1550 #elif (defined MIPSEL) 1551 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1552 #elif (defined PARISC) 1553 static Elf32_Half running_arch_code=EM_PARISC; 1554 #elif (defined MIPS) 1555 static Elf32_Half running_arch_code=EM_MIPS; 1556 #elif (defined M68K) 1557 static Elf32_Half running_arch_code=EM_68K; 1558 #else 1559 #error Method os::dll_load requires that one of following is defined:\ 1560 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1561 #endif 1562 1563 // Identify compatability class for VM's architecture and library's architecture 1564 // Obtain string descriptions for architectures 1565 1566 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1567 int running_arch_index=-1; 1568 1569 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1570 if (running_arch_code == arch_array[i].code) { 1571 running_arch_index = i; 1572 } 1573 if (lib_arch.code == arch_array[i].code) { 1574 lib_arch.compat_class = arch_array[i].compat_class; 1575 lib_arch.name = arch_array[i].name; 1576 } 1577 } 1578 1579 assert(running_arch_index != -1, 1580 "Didn't find running architecture code (running_arch_code) in arch_array"); 1581 if (running_arch_index == -1) { 1582 // Even though running architecture detection failed 1583 // we may still continue with reporting dlerror() message 1584 return NULL; 1585 } 1586 1587 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1588 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1589 return NULL; 1590 } 1591 1592 #ifndef S390 1593 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1594 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1595 return NULL; 1596 } 1597 #endif // !S390 1598 1599 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1600 if (lib_arch.name!=NULL) { 1601 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1602 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1603 lib_arch.name, arch_array[running_arch_index].name); 1604 } else { 1605 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1606 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1607 lib_arch.code, 1608 arch_array[running_arch_index].name); 1609 } 1610 } 1611 1612 return NULL; 1613 } 1614 #endif /* !__APPLE__ */ 1615 1616 void* os::get_default_process_handle() { 1617 #ifdef __APPLE__ 1618 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1619 // to avoid finding unexpected symbols on second (or later) 1620 // loads of a library. 1621 return (void*)::dlopen(NULL, RTLD_FIRST); 1622 #else 1623 return (void*)::dlopen(NULL, RTLD_LAZY); 1624 #endif 1625 } 1626 1627 // XXX: Do we need a lock around this as per Linux? 1628 void* os::dll_lookup(void* handle, const char* name) { 1629 return dlsym(handle, name); 1630 } 1631 1632 1633 static bool _print_ascii_file(const char* filename, outputStream* st) { 1634 int fd = ::open(filename, O_RDONLY); 1635 if (fd == -1) { 1636 return false; 1637 } 1638 1639 char buf[32]; 1640 int bytes; 1641 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1642 st->print_raw(buf, bytes); 1643 } 1644 1645 ::close(fd); 1646 1647 return true; 1648 } 1649 1650 void os::print_dll_info(outputStream *st) { 1651 st->print_cr("Dynamic libraries:"); 1652 #ifdef RTLD_DI_LINKMAP 1653 Dl_info dli; 1654 void *handle; 1655 Link_map *map; 1656 Link_map *p; 1657 1658 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1659 dli.dli_fname == NULL) { 1660 st->print_cr("Error: Cannot print dynamic libraries."); 1661 return; 1662 } 1663 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1664 if (handle == NULL) { 1665 st->print_cr("Error: Cannot print dynamic libraries."); 1666 return; 1667 } 1668 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1669 if (map == NULL) { 1670 st->print_cr("Error: Cannot print dynamic libraries."); 1671 return; 1672 } 1673 1674 while (map->l_prev != NULL) 1675 map = map->l_prev; 1676 1677 while (map != NULL) { 1678 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1679 map = map->l_next; 1680 } 1681 1682 dlclose(handle); 1683 #elif defined(__APPLE__) 1684 uint32_t count; 1685 uint32_t i; 1686 1687 count = _dyld_image_count(); 1688 for (i = 1; i < count; i++) { 1689 const char *name = _dyld_get_image_name(i); 1690 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 1691 st->print_cr(PTR_FORMAT " \t%s", slide, name); 1692 } 1693 #else 1694 st->print_cr("Error: Cannot print dynamic libraries."); 1695 #endif 1696 } 1697 1698 void os::print_os_info_brief(outputStream* st) { 1699 st->print("Bsd"); 1700 1701 os::Posix::print_uname_info(st); 1702 } 1703 1704 void os::print_os_info(outputStream* st) { 1705 st->print("OS:"); 1706 st->print("Bsd"); 1707 1708 os::Posix::print_uname_info(st); 1709 1710 os::Posix::print_rlimit_info(st); 1711 1712 os::Posix::print_load_average(st); 1713 } 1714 1715 void os::pd_print_cpu_info(outputStream* st) { 1716 // Nothing to do for now. 1717 } 1718 1719 void os::print_memory_info(outputStream* st) { 1720 1721 st->print("Memory:"); 1722 st->print(" %dk page", os::vm_page_size()>>10); 1723 1724 st->print(", physical " UINT64_FORMAT "k", 1725 os::physical_memory() >> 10); 1726 st->print("(" UINT64_FORMAT "k free)", 1727 os::available_memory() >> 10); 1728 st->cr(); 1729 1730 // meminfo 1731 st->print("\n/proc/meminfo:\n"); 1732 _print_ascii_file("/proc/meminfo", st); 1733 st->cr(); 1734 } 1735 1736 void os::print_siginfo(outputStream* st, void* siginfo) { 1737 const siginfo_t* si = (const siginfo_t*)siginfo; 1738 1739 os::Posix::print_siginfo_brief(st, si); 1740 1741 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1742 UseSharedSpaces) { 1743 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1744 if (mapinfo->is_in_shared_space(si->si_addr)) { 1745 st->print("\n\nError accessing class data sharing archive." \ 1746 " Mapped file inaccessible during execution, " \ 1747 " possible disk/network problem."); 1748 } 1749 } 1750 st->cr(); 1751 } 1752 1753 1754 static void print_signal_handler(outputStream* st, int sig, 1755 char* buf, size_t buflen); 1756 1757 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1758 st->print_cr("Signal Handlers:"); 1759 print_signal_handler(st, SIGSEGV, buf, buflen); 1760 print_signal_handler(st, SIGBUS , buf, buflen); 1761 print_signal_handler(st, SIGFPE , buf, buflen); 1762 print_signal_handler(st, SIGPIPE, buf, buflen); 1763 print_signal_handler(st, SIGXFSZ, buf, buflen); 1764 print_signal_handler(st, SIGILL , buf, buflen); 1765 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1766 print_signal_handler(st, SR_signum, buf, buflen); 1767 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1768 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1769 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1770 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1771 } 1772 1773 static char saved_jvm_path[MAXPATHLEN] = {0}; 1774 1775 // Find the full path to the current module, libjvm 1776 void os::jvm_path(char *buf, jint buflen) { 1777 // Error checking. 1778 if (buflen < MAXPATHLEN) { 1779 assert(false, "must use a large-enough buffer"); 1780 buf[0] = '\0'; 1781 return; 1782 } 1783 // Lazy resolve the path to current module. 1784 if (saved_jvm_path[0] != 0) { 1785 strcpy(buf, saved_jvm_path); 1786 return; 1787 } 1788 1789 char dli_fname[MAXPATHLEN]; 1790 bool ret = dll_address_to_library_name( 1791 CAST_FROM_FN_PTR(address, os::jvm_path), 1792 dli_fname, sizeof(dli_fname), NULL); 1793 assert(ret, "cannot locate libjvm"); 1794 char *rp = NULL; 1795 if (ret && dli_fname[0] != '\0') { 1796 rp = realpath(dli_fname, buf); 1797 } 1798 if (rp == NULL) 1799 return; 1800 1801 if (Arguments::sun_java_launcher_is_altjvm()) { 1802 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1803 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1804 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1805 // appears at the right place in the string, then assume we are 1806 // installed in a JDK and we're done. Otherwise, check for a 1807 // JAVA_HOME environment variable and construct a path to the JVM 1808 // being overridden. 1809 1810 const char *p = buf + strlen(buf) - 1; 1811 for (int count = 0; p > buf && count < 5; ++count) { 1812 for (--p; p > buf && *p != '/'; --p) 1813 /* empty */ ; 1814 } 1815 1816 if (strncmp(p, "/jre/lib/", 9) != 0) { 1817 // Look for JAVA_HOME in the environment. 1818 char* java_home_var = ::getenv("JAVA_HOME"); 1819 if (java_home_var != NULL && java_home_var[0] != 0) { 1820 char* jrelib_p; 1821 int len; 1822 1823 // Check the current module name "libjvm" 1824 p = strrchr(buf, '/'); 1825 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1826 1827 rp = realpath(java_home_var, buf); 1828 if (rp == NULL) 1829 return; 1830 1831 // determine if this is a legacy image or modules image 1832 // modules image doesn't have "jre" subdirectory 1833 len = strlen(buf); 1834 jrelib_p = buf + len; 1835 1836 // Add the appropriate library subdir 1837 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1838 if (0 != access(buf, F_OK)) { 1839 snprintf(jrelib_p, buflen-len, "/lib"); 1840 } 1841 1842 // Add the appropriate client or server subdir 1843 len = strlen(buf); 1844 jrelib_p = buf + len; 1845 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1846 if (0 != access(buf, F_OK)) { 1847 snprintf(jrelib_p, buflen-len, "%s", ""); 1848 } 1849 1850 // If the path exists within JAVA_HOME, add the JVM library name 1851 // to complete the path to JVM being overridden. Otherwise fallback 1852 // to the path to the current library. 1853 if (0 == access(buf, F_OK)) { 1854 // Use current module name "libjvm" 1855 len = strlen(buf); 1856 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1857 } else { 1858 // Fall back to path of current library 1859 rp = realpath(dli_fname, buf); 1860 if (rp == NULL) 1861 return; 1862 } 1863 } 1864 } 1865 } 1866 1867 strcpy(saved_jvm_path, buf); 1868 } 1869 1870 void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1871 // no prefix required, not even "_" 1872 } 1873 1874 void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1875 // no suffix required 1876 } 1877 1878 //////////////////////////////////////////////////////////////////////////////// 1879 // sun.misc.Signal support 1880 1881 static volatile jint sigint_count = 0; 1882 1883 static void 1884 UserHandler(int sig, void *siginfo, void *context) { 1885 // 4511530 - sem_post is serialized and handled by the manager thread. When 1886 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1887 // don't want to flood the manager thread with sem_post requests. 1888 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1889 return; 1890 1891 // Ctrl-C is pressed during error reporting, likely because the error 1892 // handler fails to abort. Let VM die immediately. 1893 if (sig == SIGINT && is_error_reported()) { 1894 os::die(); 1895 } 1896 1897 os::signal_notify(sig); 1898 } 1899 1900 void* os::user_handler() { 1901 return CAST_FROM_FN_PTR(void*, UserHandler); 1902 } 1903 1904 extern "C" { 1905 typedef void (*sa_handler_t)(int); 1906 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1907 } 1908 1909 void* os::signal(int signal_number, void* handler) { 1910 struct sigaction sigAct, oldSigAct; 1911 1912 sigfillset(&(sigAct.sa_mask)); 1913 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1914 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1915 1916 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1917 // -1 means registration failed 1918 return (void *)-1; 1919 } 1920 1921 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1922 } 1923 1924 void os::signal_raise(int signal_number) { 1925 ::raise(signal_number); 1926 } 1927 1928 /* 1929 * The following code is moved from os.cpp for making this 1930 * code platform specific, which it is by its very nature. 1931 */ 1932 1933 // Will be modified when max signal is changed to be dynamic 1934 int os::sigexitnum_pd() { 1935 return NSIG; 1936 } 1937 1938 // a counter for each possible signal value 1939 static volatile jint pending_signals[NSIG+1] = { 0 }; 1940 1941 // Bsd(POSIX) specific hand shaking semaphore. 1942 #ifdef __APPLE__ 1943 typedef semaphore_t os_semaphore_t; 1944 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1945 #define SEM_WAIT(sem) semaphore_wait(sem) 1946 #define SEM_POST(sem) semaphore_signal(sem) 1947 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1948 #else 1949 typedef sem_t os_semaphore_t; 1950 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1951 #define SEM_WAIT(sem) sem_wait(&sem) 1952 #define SEM_POST(sem) sem_post(&sem) 1953 #define SEM_DESTROY(sem) sem_destroy(&sem) 1954 #endif 1955 1956 class Semaphore : public StackObj { 1957 public: 1958 Semaphore(); 1959 ~Semaphore(); 1960 void signal(); 1961 void wait(); 1962 bool trywait(); 1963 bool timedwait(unsigned int sec, int nsec); 1964 private: 1965 jlong currenttime() const; 1966 os_semaphore_t _semaphore; 1967 }; 1968 1969 Semaphore::Semaphore() : _semaphore(0) { 1970 SEM_INIT(_semaphore, 0); 1971 } 1972 1973 Semaphore::~Semaphore() { 1974 SEM_DESTROY(_semaphore); 1975 } 1976 1977 void Semaphore::signal() { 1978 SEM_POST(_semaphore); 1979 } 1980 1981 void Semaphore::wait() { 1982 SEM_WAIT(_semaphore); 1983 } 1984 1985 jlong Semaphore::currenttime() const { 1986 struct timeval tv; 1987 gettimeofday(&tv, NULL); 1988 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1989 } 1990 1991 #ifdef __APPLE__ 1992 bool Semaphore::trywait() { 1993 return timedwait(0, 0); 1994 } 1995 1996 bool Semaphore::timedwait(unsigned int sec, int nsec) { 1997 kern_return_t kr = KERN_ABORTED; 1998 mach_timespec_t waitspec; 1999 waitspec.tv_sec = sec; 2000 waitspec.tv_nsec = nsec; 2001 2002 jlong starttime = currenttime(); 2003 2004 kr = semaphore_timedwait(_semaphore, waitspec); 2005 while (kr == KERN_ABORTED) { 2006 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 2007 2008 jlong current = currenttime(); 2009 jlong passedtime = current - starttime; 2010 2011 if (passedtime >= totalwait) { 2012 waitspec.tv_sec = 0; 2013 waitspec.tv_nsec = 0; 2014 } else { 2015 jlong waittime = totalwait - (current - starttime); 2016 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2017 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2018 } 2019 2020 kr = semaphore_timedwait(_semaphore, waitspec); 2021 } 2022 2023 return kr == KERN_SUCCESS; 2024 } 2025 2026 #else 2027 2028 bool Semaphore::trywait() { 2029 return sem_trywait(&_semaphore) == 0; 2030 } 2031 2032 bool Semaphore::timedwait(unsigned int sec, int nsec) { 2033 struct timespec ts; 2034 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2035 2036 while (1) { 2037 int result = sem_timedwait(&_semaphore, &ts); 2038 if (result == 0) { 2039 return true; 2040 } else if (errno == EINTR) { 2041 continue; 2042 } else if (errno == ETIMEDOUT) { 2043 return false; 2044 } else { 2045 return false; 2046 } 2047 } 2048 } 2049 2050 #endif // __APPLE__ 2051 2052 static os_semaphore_t sig_sem; 2053 static Semaphore sr_semaphore; 2054 2055 void os::signal_init_pd() { 2056 // Initialize signal structures 2057 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2058 2059 // Initialize signal semaphore 2060 ::SEM_INIT(sig_sem, 0); 2061 } 2062 2063 void os::signal_notify(int sig) { 2064 Atomic::inc(&pending_signals[sig]); 2065 ::SEM_POST(sig_sem); 2066 } 2067 2068 static int check_pending_signals(bool wait) { 2069 Atomic::store(0, &sigint_count); 2070 for (;;) { 2071 for (int i = 0; i < NSIG + 1; i++) { 2072 jint n = pending_signals[i]; 2073 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2074 return i; 2075 } 2076 } 2077 if (!wait) { 2078 return -1; 2079 } 2080 JavaThread *thread = JavaThread::current(); 2081 ThreadBlockInVM tbivm(thread); 2082 2083 bool threadIsSuspended; 2084 do { 2085 thread->set_suspend_equivalent(); 2086 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2087 ::SEM_WAIT(sig_sem); 2088 2089 // were we externally suspended while we were waiting? 2090 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2091 if (threadIsSuspended) { 2092 // 2093 // The semaphore has been incremented, but while we were waiting 2094 // another thread suspended us. We don't want to continue running 2095 // while suspended because that would surprise the thread that 2096 // suspended us. 2097 // 2098 ::SEM_POST(sig_sem); 2099 2100 thread->java_suspend_self(); 2101 } 2102 } while (threadIsSuspended); 2103 } 2104 } 2105 2106 int os::signal_lookup() { 2107 return check_pending_signals(false); 2108 } 2109 2110 int os::signal_wait() { 2111 return check_pending_signals(true); 2112 } 2113 2114 //////////////////////////////////////////////////////////////////////////////// 2115 // Virtual Memory 2116 2117 int os::vm_page_size() { 2118 // Seems redundant as all get out 2119 assert(os::Bsd::page_size() != -1, "must call os::init"); 2120 return os::Bsd::page_size(); 2121 } 2122 2123 // Solaris allocates memory by pages. 2124 int os::vm_allocation_granularity() { 2125 assert(os::Bsd::page_size() != -1, "must call os::init"); 2126 return os::Bsd::page_size(); 2127 } 2128 2129 // Rationale behind this function: 2130 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2131 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2132 // samples for JITted code. Here we create private executable mapping over the code cache 2133 // and then we can use standard (well, almost, as mapping can change) way to provide 2134 // info for the reporting script by storing timestamp and location of symbol 2135 void bsd_wrap_code(char* base, size_t size) { 2136 static volatile jint cnt = 0; 2137 2138 if (!UseOprofile) { 2139 return; 2140 } 2141 2142 char buf[PATH_MAX + 1]; 2143 int num = Atomic::add(1, &cnt); 2144 2145 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2146 os::get_temp_directory(), os::current_process_id(), num); 2147 unlink(buf); 2148 2149 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2150 2151 if (fd != -1) { 2152 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2153 if (rv != (off_t)-1) { 2154 if (::write(fd, "", 1) == 1) { 2155 mmap(base, size, 2156 PROT_READ|PROT_WRITE|PROT_EXEC, 2157 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2158 } 2159 } 2160 ::close(fd); 2161 unlink(buf); 2162 } 2163 } 2164 2165 static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2166 int err) { 2167 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2168 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2169 strerror(err), err); 2170 } 2171 2172 // NOTE: Bsd kernel does not really reserve the pages for us. 2173 // All it does is to check if there are enough free pages 2174 // left at the time of mmap(). This could be a potential 2175 // problem. 2176 bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2177 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2178 #ifdef __OpenBSD__ 2179 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2180 if (::mprotect(addr, size, prot) == 0) { 2181 return true; 2182 } 2183 #else 2184 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2185 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2186 if (res != (uintptr_t) MAP_FAILED) { 2187 return true; 2188 } 2189 #endif 2190 2191 // Warn about any commit errors we see in non-product builds just 2192 // in case mmap() doesn't work as described on the man page. 2193 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2194 2195 return false; 2196 } 2197 2198 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2199 bool exec) { 2200 // alignment_hint is ignored on this OS 2201 return pd_commit_memory(addr, size, exec); 2202 } 2203 2204 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2205 const char* mesg) { 2206 assert(mesg != NULL, "mesg must be specified"); 2207 if (!pd_commit_memory(addr, size, exec)) { 2208 // add extra info in product mode for vm_exit_out_of_memory(): 2209 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2210 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2211 } 2212 } 2213 2214 void os::pd_commit_memory_or_exit(char* addr, size_t size, 2215 size_t alignment_hint, bool exec, 2216 const char* mesg) { 2217 // alignment_hint is ignored on this OS 2218 pd_commit_memory_or_exit(addr, size, exec, mesg); 2219 } 2220 2221 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2222 } 2223 2224 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2225 ::madvise(addr, bytes, MADV_DONTNEED); 2226 } 2227 2228 void os::numa_make_global(char *addr, size_t bytes) { 2229 } 2230 2231 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2232 } 2233 2234 bool os::numa_topology_changed() { return false; } 2235 2236 size_t os::numa_get_groups_num() { 2237 return 1; 2238 } 2239 2240 int os::numa_get_group_id() { 2241 return 0; 2242 } 2243 2244 size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2245 if (size > 0) { 2246 ids[0] = 0; 2247 return 1; 2248 } 2249 return 0; 2250 } 2251 2252 bool os::get_page_info(char *start, page_info* info) { 2253 return false; 2254 } 2255 2256 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2257 return end; 2258 } 2259 2260 2261 bool os::pd_uncommit_memory(char* addr, size_t size) { 2262 #ifdef __OpenBSD__ 2263 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2264 return ::mprotect(addr, size, PROT_NONE) == 0; 2265 #else 2266 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2267 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2268 return res != (uintptr_t) MAP_FAILED; 2269 #endif 2270 } 2271 2272 bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2273 return os::commit_memory(addr, size, !ExecMem); 2274 } 2275 2276 // If this is a growable mapping, remove the guard pages entirely by 2277 // munmap()ping them. If not, just call uncommit_memory(). 2278 bool os::remove_stack_guard_pages(char* addr, size_t size) { 2279 return os::uncommit_memory(addr, size); 2280 } 2281 2282 static address _highest_vm_reserved_address = NULL; 2283 2284 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2285 // at 'requested_addr'. If there are existing memory mappings at the same 2286 // location, however, they will be overwritten. If 'fixed' is false, 2287 // 'requested_addr' is only treated as a hint, the return value may or 2288 // may not start from the requested address. Unlike Bsd mmap(), this 2289 // function returns NULL to indicate failure. 2290 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2291 char * addr; 2292 int flags; 2293 2294 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2295 if (fixed) { 2296 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2297 flags |= MAP_FIXED; 2298 } 2299 2300 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2301 // touch an uncommitted page. Otherwise, the read/write might 2302 // succeed if we have enough swap space to back the physical page. 2303 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2304 flags, -1, 0); 2305 2306 if (addr != MAP_FAILED) { 2307 // anon_mmap() should only get called during VM initialization, 2308 // don't need lock (actually we can skip locking even it can be called 2309 // from multiple threads, because _highest_vm_reserved_address is just a 2310 // hint about the upper limit of non-stack memory regions.) 2311 if ((address)addr + bytes > _highest_vm_reserved_address) { 2312 _highest_vm_reserved_address = (address)addr + bytes; 2313 } 2314 } 2315 2316 return addr == MAP_FAILED ? NULL : addr; 2317 } 2318 2319 // Don't update _highest_vm_reserved_address, because there might be memory 2320 // regions above addr + size. If so, releasing a memory region only creates 2321 // a hole in the address space, it doesn't help prevent heap-stack collision. 2322 // 2323 static int anon_munmap(char * addr, size_t size) { 2324 return ::munmap(addr, size) == 0; 2325 } 2326 2327 char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2328 size_t alignment_hint) { 2329 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2330 } 2331 2332 bool os::pd_release_memory(char* addr, size_t size) { 2333 return anon_munmap(addr, size); 2334 } 2335 2336 static bool bsd_mprotect(char* addr, size_t size, int prot) { 2337 // Bsd wants the mprotect address argument to be page aligned. 2338 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2339 2340 // According to SUSv3, mprotect() should only be used with mappings 2341 // established by mmap(), and mmap() always maps whole pages. Unaligned 2342 // 'addr' likely indicates problem in the VM (e.g. trying to change 2343 // protection of malloc'ed or statically allocated memory). Check the 2344 // caller if you hit this assert. 2345 assert(addr == bottom, "sanity check"); 2346 2347 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2348 return ::mprotect(bottom, size, prot) == 0; 2349 } 2350 2351 // Set protections specified 2352 bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2353 bool is_committed) { 2354 unsigned int p = 0; 2355 switch (prot) { 2356 case MEM_PROT_NONE: p = PROT_NONE; break; 2357 case MEM_PROT_READ: p = PROT_READ; break; 2358 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2359 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2360 default: 2361 ShouldNotReachHere(); 2362 } 2363 // is_committed is unused. 2364 return bsd_mprotect(addr, bytes, p); 2365 } 2366 2367 bool os::guard_memory(char* addr, size_t size) { 2368 return bsd_mprotect(addr, size, PROT_NONE); 2369 } 2370 2371 bool os::unguard_memory(char* addr, size_t size) { 2372 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2373 } 2374 2375 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2376 return false; 2377 } 2378 2379 // Large page support 2380 2381 static size_t _large_page_size = 0; 2382 2383 void os::large_page_init() { 2384 } 2385 2386 2387 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2388 fatal("This code is not used or maintained."); 2389 2390 // "exec" is passed in but not used. Creating the shared image for 2391 // the code cache doesn't have an SHM_X executable permission to check. 2392 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2393 2394 key_t key = IPC_PRIVATE; 2395 char *addr; 2396 2397 bool warn_on_failure = UseLargePages && 2398 (!FLAG_IS_DEFAULT(UseLargePages) || 2399 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2400 ); 2401 2402 // Create a large shared memory region to attach to based on size. 2403 // Currently, size is the total size of the heap 2404 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2405 if (shmid == -1) { 2406 // Possible reasons for shmget failure: 2407 // 1. shmmax is too small for Java heap. 2408 // > check shmmax value: cat /proc/sys/kernel/shmmax 2409 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2410 // 2. not enough large page memory. 2411 // > check available large pages: cat /proc/meminfo 2412 // > increase amount of large pages: 2413 // echo new_value > /proc/sys/vm/nr_hugepages 2414 // Note 1: different Bsd may use different name for this property, 2415 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2416 // Note 2: it's possible there's enough physical memory available but 2417 // they are so fragmented after a long run that they can't 2418 // coalesce into large pages. Try to reserve large pages when 2419 // the system is still "fresh". 2420 if (warn_on_failure) { 2421 warning("Failed to reserve shared memory (errno = %d).", errno); 2422 } 2423 return NULL; 2424 } 2425 2426 // attach to the region 2427 addr = (char*)shmat(shmid, req_addr, 0); 2428 int err = errno; 2429 2430 // Remove shmid. If shmat() is successful, the actual shared memory segment 2431 // will be deleted when it's detached by shmdt() or when the process 2432 // terminates. If shmat() is not successful this will remove the shared 2433 // segment immediately. 2434 shmctl(shmid, IPC_RMID, NULL); 2435 2436 if ((intptr_t)addr == -1) { 2437 if (warn_on_failure) { 2438 warning("Failed to attach shared memory (errno = %d).", err); 2439 } 2440 return NULL; 2441 } 2442 2443 // The memory is committed 2444 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC); 2445 2446 return addr; 2447 } 2448 2449 bool os::release_memory_special(char* base, size_t bytes) { 2450 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2451 // detaching the SHM segment will also delete it, see reserve_memory_special() 2452 int rslt = shmdt(base); 2453 if (rslt == 0) { 2454 tkr.record((address)base, bytes); 2455 return true; 2456 } else { 2457 tkr.discard(); 2458 return false; 2459 } 2460 2461 } 2462 2463 size_t os::large_page_size() { 2464 return _large_page_size; 2465 } 2466 2467 // HugeTLBFS allows application to commit large page memory on demand; 2468 // with SysV SHM the entire memory region must be allocated as shared 2469 // memory. 2470 bool os::can_commit_large_page_memory() { 2471 return UseHugeTLBFS; 2472 } 2473 2474 bool os::can_execute_large_page_memory() { 2475 return UseHugeTLBFS; 2476 } 2477 2478 // Reserve memory at an arbitrary address, only if that area is 2479 // available (and not reserved for something else). 2480 2481 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2482 const int max_tries = 10; 2483 char* base[max_tries]; 2484 size_t size[max_tries]; 2485 const size_t gap = 0x000000; 2486 2487 // Assert only that the size is a multiple of the page size, since 2488 // that's all that mmap requires, and since that's all we really know 2489 // about at this low abstraction level. If we need higher alignment, 2490 // we can either pass an alignment to this method or verify alignment 2491 // in one of the methods further up the call chain. See bug 5044738. 2492 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2493 2494 // Repeatedly allocate blocks until the block is allocated at the 2495 // right spot. Give up after max_tries. Note that reserve_memory() will 2496 // automatically update _highest_vm_reserved_address if the call is 2497 // successful. The variable tracks the highest memory address every reserved 2498 // by JVM. It is used to detect heap-stack collision if running with 2499 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2500 // space than needed, it could confuse the collision detecting code. To 2501 // solve the problem, save current _highest_vm_reserved_address and 2502 // calculate the correct value before return. 2503 address old_highest = _highest_vm_reserved_address; 2504 2505 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2506 // if kernel honors the hint then we can return immediately. 2507 char * addr = anon_mmap(requested_addr, bytes, false); 2508 if (addr == requested_addr) { 2509 return requested_addr; 2510 } 2511 2512 if (addr != NULL) { 2513 // mmap() is successful but it fails to reserve at the requested address 2514 anon_munmap(addr, bytes); 2515 } 2516 2517 int i; 2518 for (i = 0; i < max_tries; ++i) { 2519 base[i] = reserve_memory(bytes); 2520 2521 if (base[i] != NULL) { 2522 // Is this the block we wanted? 2523 if (base[i] == requested_addr) { 2524 size[i] = bytes; 2525 break; 2526 } 2527 2528 // Does this overlap the block we wanted? Give back the overlapped 2529 // parts and try again. 2530 2531 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2532 if (top_overlap >= 0 && top_overlap < bytes) { 2533 unmap_memory(base[i], top_overlap); 2534 base[i] += top_overlap; 2535 size[i] = bytes - top_overlap; 2536 } else { 2537 size_t bottom_overlap = base[i] + bytes - requested_addr; 2538 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2539 unmap_memory(requested_addr, bottom_overlap); 2540 size[i] = bytes - bottom_overlap; 2541 } else { 2542 size[i] = bytes; 2543 } 2544 } 2545 } 2546 } 2547 2548 // Give back the unused reserved pieces. 2549 2550 for (int j = 0; j < i; ++j) { 2551 if (base[j] != NULL) { 2552 unmap_memory(base[j], size[j]); 2553 } 2554 } 2555 2556 if (i < max_tries) { 2557 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2558 return requested_addr; 2559 } else { 2560 _highest_vm_reserved_address = old_highest; 2561 return NULL; 2562 } 2563 } 2564 2565 size_t os::read(int fd, void *buf, unsigned int nBytes) { 2566 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2567 } 2568 2569 void os::naked_short_sleep(jlong ms) { 2570 struct timespec req; 2571 2572 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2573 req.tv_sec = 0; 2574 if (ms > 0) { 2575 req.tv_nsec = (ms % 1000) * 1000000; 2576 } 2577 else { 2578 req.tv_nsec = 1; 2579 } 2580 2581 nanosleep(&req, NULL); 2582 2583 return; 2584 } 2585 2586 // Sleep forever; naked call to OS-specific sleep; use with CAUTION 2587 void os::infinite_sleep() { 2588 while (true) { // sleep forever ... 2589 ::sleep(100); // ... 100 seconds at a time 2590 } 2591 } 2592 2593 // Used to convert frequent JVM_Yield() to nops 2594 bool os::dont_yield() { 2595 return DontYieldALot; 2596 } 2597 2598 void os::yield() { 2599 sched_yield(); 2600 } 2601 2602 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN; } 2603 2604 void os::yield_all() { 2605 // Yields to all threads, including threads with lower priorities 2606 // Threads on Bsd are all with same priority. The Solaris style 2607 // os::yield_all() with nanosleep(1ms) is not necessary. 2608 sched_yield(); 2609 } 2610 2611 //////////////////////////////////////////////////////////////////////////////// 2612 // thread priority support 2613 2614 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2615 // only supports dynamic priority, static priority must be zero. For real-time 2616 // applications, Bsd supports SCHED_RR which allows static priority (1-99). 2617 // However, for large multi-threaded applications, SCHED_RR is not only slower 2618 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2619 // of 5 runs - Sep 2005). 2620 // 2621 // The following code actually changes the niceness of kernel-thread/LWP. It 2622 // has an assumption that setpriority() only modifies one kernel-thread/LWP, 2623 // not the entire user process, and user level threads are 1:1 mapped to kernel 2624 // threads. It has always been the case, but could change in the future. For 2625 // this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2626 // It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2627 2628 #if !defined(__APPLE__) 2629 int os::java_to_os_priority[CriticalPriority + 1] = { 2630 19, // 0 Entry should never be used 2631 2632 0, // 1 MinPriority 2633 3, // 2 2634 6, // 3 2635 2636 10, // 4 2637 15, // 5 NormPriority 2638 18, // 6 2639 2640 21, // 7 2641 25, // 8 2642 28, // 9 NearMaxPriority 2643 2644 31, // 10 MaxPriority 2645 2646 31 // 11 CriticalPriority 2647 }; 2648 #else 2649 /* Using Mach high-level priority assignments */ 2650 int os::java_to_os_priority[CriticalPriority + 1] = { 2651 0, // 0 Entry should never be used (MINPRI_USER) 2652 2653 27, // 1 MinPriority 2654 28, // 2 2655 29, // 3 2656 2657 30, // 4 2658 31, // 5 NormPriority (BASEPRI_DEFAULT) 2659 32, // 6 2660 2661 33, // 7 2662 34, // 8 2663 35, // 9 NearMaxPriority 2664 2665 36, // 10 MaxPriority 2666 2667 36 // 11 CriticalPriority 2668 }; 2669 #endif 2670 2671 static int prio_init() { 2672 if (ThreadPriorityPolicy == 1) { 2673 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2674 // if effective uid is not root. Perhaps, a more elegant way of doing 2675 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2676 if (geteuid() != 0) { 2677 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2678 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2679 } 2680 ThreadPriorityPolicy = 0; 2681 } 2682 } 2683 if (UseCriticalJavaThreadPriority) { 2684 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2685 } 2686 return 0; 2687 } 2688 2689 OSReturn os::set_native_priority(Thread* thread, int newpri) { 2690 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2691 2692 #ifdef __OpenBSD__ 2693 // OpenBSD pthread_setprio starves low priority threads 2694 return OS_OK; 2695 #elif defined(__FreeBSD__) 2696 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2697 #elif defined(__APPLE__) || defined(__NetBSD__) 2698 struct sched_param sp; 2699 int policy; 2700 pthread_t self = pthread_self(); 2701 2702 if (pthread_getschedparam(self, &policy, &sp) != 0) 2703 return OS_ERR; 2704 2705 sp.sched_priority = newpri; 2706 if (pthread_setschedparam(self, policy, &sp) != 0) 2707 return OS_ERR; 2708 2709 return OS_OK; 2710 #else 2711 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2712 return (ret == 0) ? OS_OK : OS_ERR; 2713 #endif 2714 } 2715 2716 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2717 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2718 *priority_ptr = java_to_os_priority[NormPriority]; 2719 return OS_OK; 2720 } 2721 2722 errno = 0; 2723 #if defined(__OpenBSD__) || defined(__FreeBSD__) 2724 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2725 #elif defined(__APPLE__) || defined(__NetBSD__) 2726 int policy; 2727 struct sched_param sp; 2728 2729 pthread_getschedparam(pthread_self(), &policy, &sp); 2730 *priority_ptr = sp.sched_priority; 2731 #else 2732 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2733 #endif 2734 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2735 } 2736 2737 // Hint to the underlying OS that a task switch would not be good. 2738 // Void return because it's a hint and can fail. 2739 void os::hint_no_preempt() {} 2740 2741 //////////////////////////////////////////////////////////////////////////////// 2742 // suspend/resume support 2743 2744 // the low-level signal-based suspend/resume support is a remnant from the 2745 // old VM-suspension that used to be for java-suspension, safepoints etc, 2746 // within hotspot. Now there is a single use-case for this: 2747 // - calling get_thread_pc() on the VMThread by the flat-profiler task 2748 // that runs in the watcher thread. 2749 // The remaining code is greatly simplified from the more general suspension 2750 // code that used to be used. 2751 // 2752 // The protocol is quite simple: 2753 // - suspend: 2754 // - sends a signal to the target thread 2755 // - polls the suspend state of the osthread using a yield loop 2756 // - target thread signal handler (SR_handler) sets suspend state 2757 // and blocks in sigsuspend until continued 2758 // - resume: 2759 // - sets target osthread state to continue 2760 // - sends signal to end the sigsuspend loop in the SR_handler 2761 // 2762 // Note that the SR_lock plays no role in this suspend/resume protocol. 2763 // 2764 2765 static void resume_clear_context(OSThread *osthread) { 2766 osthread->set_ucontext(NULL); 2767 osthread->set_siginfo(NULL); 2768 } 2769 2770 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2771 osthread->set_ucontext(context); 2772 osthread->set_siginfo(siginfo); 2773 } 2774 2775 // 2776 // Handler function invoked when a thread's execution is suspended or 2777 // resumed. We have to be careful that only async-safe functions are 2778 // called here (Note: most pthread functions are not async safe and 2779 // should be avoided.) 2780 // 2781 // Note: sigwait() is a more natural fit than sigsuspend() from an 2782 // interface point of view, but sigwait() prevents the signal hander 2783 // from being run. libpthread would get very confused by not having 2784 // its signal handlers run and prevents sigwait()'s use with the 2785 // mutex granting granting signal. 2786 // 2787 // Currently only ever called on the VMThread or JavaThread 2788 // 2789 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2790 // Save and restore errno to avoid confusing native code with EINTR 2791 // after sigsuspend. 2792 int old_errno = errno; 2793 2794 Thread* thread = Thread::current(); 2795 OSThread* osthread = thread->osthread(); 2796 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2797 2798 os::SuspendResume::State current = osthread->sr.state(); 2799 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2800 suspend_save_context(osthread, siginfo, context); 2801 2802 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2803 os::SuspendResume::State state = osthread->sr.suspended(); 2804 if (state == os::SuspendResume::SR_SUSPENDED) { 2805 sigset_t suspend_set; // signals for sigsuspend() 2806 2807 // get current set of blocked signals and unblock resume signal 2808 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2809 sigdelset(&suspend_set, SR_signum); 2810 2811 sr_semaphore.signal(); 2812 // wait here until we are resumed 2813 while (1) { 2814 sigsuspend(&suspend_set); 2815 2816 os::SuspendResume::State result = osthread->sr.running(); 2817 if (result == os::SuspendResume::SR_RUNNING) { 2818 sr_semaphore.signal(); 2819 break; 2820 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2821 ShouldNotReachHere(); 2822 } 2823 } 2824 2825 } else if (state == os::SuspendResume::SR_RUNNING) { 2826 // request was cancelled, continue 2827 } else { 2828 ShouldNotReachHere(); 2829 } 2830 2831 resume_clear_context(osthread); 2832 } else if (current == os::SuspendResume::SR_RUNNING) { 2833 // request was cancelled, continue 2834 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2835 // ignore 2836 } else { 2837 // ignore 2838 } 2839 2840 errno = old_errno; 2841 } 2842 2843 2844 static int SR_initialize() { 2845 struct sigaction act; 2846 char *s; 2847 /* Get signal number to use for suspend/resume */ 2848 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2849 int sig = ::strtol(s, 0, 10); 2850 if (sig > 0 || sig < NSIG) { 2851 SR_signum = sig; 2852 } 2853 } 2854 2855 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2856 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2857 2858 sigemptyset(&SR_sigset); 2859 sigaddset(&SR_sigset, SR_signum); 2860 2861 /* Set up signal handler for suspend/resume */ 2862 act.sa_flags = SA_RESTART|SA_SIGINFO; 2863 act.sa_handler = (void (*)(int)) SR_handler; 2864 2865 // SR_signum is blocked by default. 2866 // 4528190 - We also need to block pthread restart signal (32 on all 2867 // supported Bsd platforms). Note that BsdThreads need to block 2868 // this signal for all threads to work properly. So we don't have 2869 // to use hard-coded signal number when setting up the mask. 2870 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2871 2872 if (sigaction(SR_signum, &act, 0) == -1) { 2873 return -1; 2874 } 2875 2876 // Save signal flag 2877 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2878 return 0; 2879 } 2880 2881 static int sr_notify(OSThread* osthread) { 2882 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2883 assert_status(status == 0, status, "pthread_kill"); 2884 return status; 2885 } 2886 2887 // "Randomly" selected value for how long we want to spin 2888 // before bailing out on suspending a thread, also how often 2889 // we send a signal to a thread we want to resume 2890 static const int RANDOMLY_LARGE_INTEGER = 1000000; 2891 static const int RANDOMLY_LARGE_INTEGER2 = 100; 2892 2893 // returns true on success and false on error - really an error is fatal 2894 // but this seems the normal response to library errors 2895 static bool do_suspend(OSThread* osthread) { 2896 assert(osthread->sr.is_running(), "thread should be running"); 2897 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2898 2899 // mark as suspended and send signal 2900 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2901 // failed to switch, state wasn't running? 2902 ShouldNotReachHere(); 2903 return false; 2904 } 2905 2906 if (sr_notify(osthread) != 0) { 2907 ShouldNotReachHere(); 2908 } 2909 2910 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2911 while (true) { 2912 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2913 break; 2914 } else { 2915 // timeout 2916 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2917 if (cancelled == os::SuspendResume::SR_RUNNING) { 2918 return false; 2919 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2920 // make sure that we consume the signal on the semaphore as well 2921 sr_semaphore.wait(); 2922 break; 2923 } else { 2924 ShouldNotReachHere(); 2925 return false; 2926 } 2927 } 2928 } 2929 2930 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2931 return true; 2932 } 2933 2934 static void do_resume(OSThread* osthread) { 2935 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2936 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2937 2938 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2939 // failed to switch to WAKEUP_REQUEST 2940 ShouldNotReachHere(); 2941 return; 2942 } 2943 2944 while (true) { 2945 if (sr_notify(osthread) == 0) { 2946 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2947 if (osthread->sr.is_running()) { 2948 return; 2949 } 2950 } 2951 } else { 2952 ShouldNotReachHere(); 2953 } 2954 } 2955 2956 guarantee(osthread->sr.is_running(), "Must be running!"); 2957 } 2958 2959 /////////////////////////////////////////////////////////////////////////////////// 2960 // signal handling (except suspend/resume) 2961 2962 // This routine may be used by user applications as a "hook" to catch signals. 2963 // The user-defined signal handler must pass unrecognized signals to this 2964 // routine, and if it returns true (non-zero), then the signal handler must 2965 // return immediately. If the flag "abort_if_unrecognized" is true, then this 2966 // routine will never retun false (zero), but instead will execute a VM panic 2967 // routine kill the process. 2968 // 2969 // If this routine returns false, it is OK to call it again. This allows 2970 // the user-defined signal handler to perform checks either before or after 2971 // the VM performs its own checks. Naturally, the user code would be making 2972 // a serious error if it tried to handle an exception (such as a null check 2973 // or breakpoint) that the VM was generating for its own correct operation. 2974 // 2975 // This routine may recognize any of the following kinds of signals: 2976 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2977 // It should be consulted by handlers for any of those signals. 2978 // 2979 // The caller of this routine must pass in the three arguments supplied 2980 // to the function referred to in the "sa_sigaction" (not the "sa_handler") 2981 // field of the structure passed to sigaction(). This routine assumes that 2982 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2983 // 2984 // Note that the VM will print warnings if it detects conflicting signal 2985 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2986 // 2987 extern "C" JNIEXPORT int 2988 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2989 void* ucontext, int abort_if_unrecognized); 2990 2991 void signalHandler(int sig, siginfo_t* info, void* uc) { 2992 assert(info != NULL && uc != NULL, "it must be old kernel"); 2993 int orig_errno = errno; // Preserve errno value over signal handler. 2994 JVM_handle_bsd_signal(sig, info, uc, true); 2995 errno = orig_errno; 2996 } 2997 2998 2999 // This boolean allows users to forward their own non-matching signals 3000 // to JVM_handle_bsd_signal, harmlessly. 3001 bool os::Bsd::signal_handlers_are_installed = false; 3002 3003 // For signal-chaining 3004 struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3005 unsigned int os::Bsd::sigs = 0; 3006 bool os::Bsd::libjsig_is_loaded = false; 3007 typedef struct sigaction *(*get_signal_t)(int); 3008 get_signal_t os::Bsd::get_signal_action = NULL; 3009 3010 struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3011 struct sigaction *actp = NULL; 3012 3013 if (libjsig_is_loaded) { 3014 // Retrieve the old signal handler from libjsig 3015 actp = (*get_signal_action)(sig); 3016 } 3017 if (actp == NULL) { 3018 // Retrieve the preinstalled signal handler from jvm 3019 actp = get_preinstalled_handler(sig); 3020 } 3021 3022 return actp; 3023 } 3024 3025 static bool call_chained_handler(struct sigaction *actp, int sig, 3026 siginfo_t *siginfo, void *context) { 3027 // Call the old signal handler 3028 if (actp->sa_handler == SIG_DFL) { 3029 // It's more reasonable to let jvm treat it as an unexpected exception 3030 // instead of taking the default action. 3031 return false; 3032 } else if (actp->sa_handler != SIG_IGN) { 3033 if ((actp->sa_flags & SA_NODEFER) == 0) { 3034 // automaticlly block the signal 3035 sigaddset(&(actp->sa_mask), sig); 3036 } 3037 3038 sa_handler_t hand; 3039 sa_sigaction_t sa; 3040 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3041 // retrieve the chained handler 3042 if (siginfo_flag_set) { 3043 sa = actp->sa_sigaction; 3044 } else { 3045 hand = actp->sa_handler; 3046 } 3047 3048 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3049 actp->sa_handler = SIG_DFL; 3050 } 3051 3052 // try to honor the signal mask 3053 sigset_t oset; 3054 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3055 3056 // call into the chained handler 3057 if (siginfo_flag_set) { 3058 (*sa)(sig, siginfo, context); 3059 } else { 3060 (*hand)(sig); 3061 } 3062 3063 // restore the signal mask 3064 pthread_sigmask(SIG_SETMASK, &oset, 0); 3065 } 3066 // Tell jvm's signal handler the signal is taken care of. 3067 return true; 3068 } 3069 3070 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3071 bool chained = false; 3072 // signal-chaining 3073 if (UseSignalChaining) { 3074 struct sigaction *actp = get_chained_signal_action(sig); 3075 if (actp != NULL) { 3076 chained = call_chained_handler(actp, sig, siginfo, context); 3077 } 3078 } 3079 return chained; 3080 } 3081 3082 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3083 if ((((unsigned int)1 << sig) & sigs) != 0) { 3084 return &sigact[sig]; 3085 } 3086 return NULL; 3087 } 3088 3089 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3090 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3091 sigact[sig] = oldAct; 3092 sigs |= (unsigned int)1 << sig; 3093 } 3094 3095 // for diagnostic 3096 int os::Bsd::sigflags[MAXSIGNUM]; 3097 3098 int os::Bsd::get_our_sigflags(int sig) { 3099 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3100 return sigflags[sig]; 3101 } 3102 3103 void os::Bsd::set_our_sigflags(int sig, int flags) { 3104 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3105 sigflags[sig] = flags; 3106 } 3107 3108 void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3109 // Check for overwrite. 3110 struct sigaction oldAct; 3111 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3112 3113 void* oldhand = oldAct.sa_sigaction 3114 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3115 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3116 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3117 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3118 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3119 if (AllowUserSignalHandlers || !set_installed) { 3120 // Do not overwrite; user takes responsibility to forward to us. 3121 return; 3122 } else if (UseSignalChaining) { 3123 // save the old handler in jvm 3124 save_preinstalled_handler(sig, oldAct); 3125 // libjsig also interposes the sigaction() call below and saves the 3126 // old sigaction on it own. 3127 } else { 3128 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3129 "%#lx for signal %d.", (long)oldhand, sig)); 3130 } 3131 } 3132 3133 struct sigaction sigAct; 3134 sigfillset(&(sigAct.sa_mask)); 3135 sigAct.sa_handler = SIG_DFL; 3136 if (!set_installed) { 3137 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3138 } else { 3139 sigAct.sa_sigaction = signalHandler; 3140 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3141 } 3142 #ifdef __APPLE__ 3143 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3144 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3145 // if the signal handler declares it will handle it on alternate stack. 3146 // Notice we only declare we will handle it on alt stack, but we are not 3147 // actually going to use real alt stack - this is just a workaround. 3148 // Please see ux_exception.c, method catch_mach_exception_raise for details 3149 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3150 if (sig == SIGSEGV) { 3151 sigAct.sa_flags |= SA_ONSTACK; 3152 } 3153 #endif 3154 3155 // Save flags, which are set by ours 3156 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3157 sigflags[sig] = sigAct.sa_flags; 3158 3159 int ret = sigaction(sig, &sigAct, &oldAct); 3160 assert(ret == 0, "check"); 3161 3162 void* oldhand2 = oldAct.sa_sigaction 3163 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3164 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3165 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3166 } 3167 3168 // install signal handlers for signals that HotSpot needs to 3169 // handle in order to support Java-level exception handling. 3170 3171 void os::Bsd::install_signal_handlers() { 3172 if (!signal_handlers_are_installed) { 3173 signal_handlers_are_installed = true; 3174 3175 // signal-chaining 3176 typedef void (*signal_setting_t)(); 3177 signal_setting_t begin_signal_setting = NULL; 3178 signal_setting_t end_signal_setting = NULL; 3179 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3180 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3181 if (begin_signal_setting != NULL) { 3182 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3183 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3184 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3185 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3186 libjsig_is_loaded = true; 3187 assert(UseSignalChaining, "should enable signal-chaining"); 3188 } 3189 if (libjsig_is_loaded) { 3190 // Tell libjsig jvm is setting signal handlers 3191 (*begin_signal_setting)(); 3192 } 3193 3194 set_signal_handler(SIGSEGV, true); 3195 set_signal_handler(SIGPIPE, true); 3196 set_signal_handler(SIGBUS, true); 3197 set_signal_handler(SIGILL, true); 3198 set_signal_handler(SIGFPE, true); 3199 set_signal_handler(SIGXFSZ, true); 3200 3201 #if defined(__APPLE__) 3202 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3203 // signals caught and handled by the JVM. To work around this, we reset the mach task 3204 // signal handler that's placed on our process by CrashReporter. This disables 3205 // CrashReporter-based reporting. 3206 // 3207 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3208 // on caught fatal signals. 3209 // 3210 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3211 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3212 // exception handling, while leaving the standard BSD signal handlers functional. 3213 kern_return_t kr; 3214 kr = task_set_exception_ports(mach_task_self(), 3215 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3216 MACH_PORT_NULL, 3217 EXCEPTION_STATE_IDENTITY, 3218 MACHINE_THREAD_STATE); 3219 3220 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3221 #endif 3222 3223 if (libjsig_is_loaded) { 3224 // Tell libjsig jvm finishes setting signal handlers 3225 (*end_signal_setting)(); 3226 } 3227 3228 // We don't activate signal checker if libjsig is in place, we trust ourselves 3229 // and if UserSignalHandler is installed all bets are off 3230 if (CheckJNICalls) { 3231 if (libjsig_is_loaded) { 3232 if (PrintJNIResolving) { 3233 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3234 } 3235 check_signals = false; 3236 } 3237 if (AllowUserSignalHandlers) { 3238 if (PrintJNIResolving) { 3239 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3240 } 3241 check_signals = false; 3242 } 3243 } 3244 } 3245 } 3246 3247 3248 ///// 3249 // glibc on Bsd platform uses non-documented flag 3250 // to indicate, that some special sort of signal 3251 // trampoline is used. 3252 // We will never set this flag, and we should 3253 // ignore this flag in our diagnostic 3254 #ifdef SIGNIFICANT_SIGNAL_MASK 3255 #undef SIGNIFICANT_SIGNAL_MASK 3256 #endif 3257 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3258 3259 static const char* get_signal_handler_name(address handler, 3260 char* buf, int buflen) { 3261 int offset; 3262 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3263 if (found) { 3264 // skip directory names 3265 const char *p1, *p2; 3266 p1 = buf; 3267 size_t len = strlen(os::file_separator()); 3268 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3269 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3270 } else { 3271 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3272 } 3273 return buf; 3274 } 3275 3276 static void print_signal_handler(outputStream* st, int sig, 3277 char* buf, size_t buflen) { 3278 struct sigaction sa; 3279 3280 sigaction(sig, NULL, &sa); 3281 3282 // See comment for SIGNIFICANT_SIGNAL_MASK define 3283 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3284 3285 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3286 3287 address handler = (sa.sa_flags & SA_SIGINFO) 3288 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3289 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3290 3291 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3292 st->print("SIG_DFL"); 3293 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3294 st->print("SIG_IGN"); 3295 } else { 3296 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3297 } 3298 3299 st->print(", sa_mask[0]="); 3300 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3301 3302 address rh = VMError::get_resetted_sighandler(sig); 3303 // May be, handler was resetted by VMError? 3304 if (rh != NULL) { 3305 handler = rh; 3306 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3307 } 3308 3309 st->print(", sa_flags="); 3310 os::Posix::print_sa_flags(st, sa.sa_flags); 3311 3312 // Check: is it our handler? 3313 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3314 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3315 // It is our signal handler 3316 // check for flags, reset system-used one! 3317 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3318 st->print( 3319 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3320 os::Bsd::get_our_sigflags(sig)); 3321 } 3322 } 3323 st->cr(); 3324 } 3325 3326 3327 #define DO_SIGNAL_CHECK(sig) \ 3328 if (!sigismember(&check_signal_done, sig)) \ 3329 os::Bsd::check_signal_handler(sig) 3330 3331 // This method is a periodic task to check for misbehaving JNI applications 3332 // under CheckJNI, we can add any periodic checks here 3333 3334 void os::run_periodic_checks() { 3335 3336 if (check_signals == false) return; 3337 3338 // SEGV and BUS if overridden could potentially prevent 3339 // generation of hs*.log in the event of a crash, debugging 3340 // such a case can be very challenging, so we absolutely 3341 // check the following for a good measure: 3342 DO_SIGNAL_CHECK(SIGSEGV); 3343 DO_SIGNAL_CHECK(SIGILL); 3344 DO_SIGNAL_CHECK(SIGFPE); 3345 DO_SIGNAL_CHECK(SIGBUS); 3346 DO_SIGNAL_CHECK(SIGPIPE); 3347 DO_SIGNAL_CHECK(SIGXFSZ); 3348 3349 3350 // ReduceSignalUsage allows the user to override these handlers 3351 // see comments at the very top and jvm_solaris.h 3352 if (!ReduceSignalUsage) { 3353 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3354 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3355 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3356 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3357 } 3358 3359 DO_SIGNAL_CHECK(SR_signum); 3360 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3361 } 3362 3363 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3364 3365 static os_sigaction_t os_sigaction = NULL; 3366 3367 void os::Bsd::check_signal_handler(int sig) { 3368 char buf[O_BUFLEN]; 3369 address jvmHandler = NULL; 3370 3371 3372 struct sigaction act; 3373 if (os_sigaction == NULL) { 3374 // only trust the default sigaction, in case it has been interposed 3375 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3376 if (os_sigaction == NULL) return; 3377 } 3378 3379 os_sigaction(sig, (struct sigaction*)NULL, &act); 3380 3381 3382 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3383 3384 address thisHandler = (act.sa_flags & SA_SIGINFO) 3385 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3386 : CAST_FROM_FN_PTR(address, act.sa_handler); 3387 3388 3389 switch (sig) { 3390 case SIGSEGV: 3391 case SIGBUS: 3392 case SIGFPE: 3393 case SIGPIPE: 3394 case SIGILL: 3395 case SIGXFSZ: 3396 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3397 break; 3398 3399 case SHUTDOWN1_SIGNAL: 3400 case SHUTDOWN2_SIGNAL: 3401 case SHUTDOWN3_SIGNAL: 3402 case BREAK_SIGNAL: 3403 jvmHandler = (address)user_handler(); 3404 break; 3405 3406 case INTERRUPT_SIGNAL: 3407 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3408 break; 3409 3410 default: 3411 if (sig == SR_signum) { 3412 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3413 } else { 3414 return; 3415 } 3416 break; 3417 } 3418 3419 if (thisHandler != jvmHandler) { 3420 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3421 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3422 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3423 // No need to check this sig any longer 3424 sigaddset(&check_signal_done, sig); 3425 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3426 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3427 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3428 exception_name(sig, buf, O_BUFLEN)); 3429 } 3430 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3431 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3432 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3433 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3434 // No need to check this sig any longer 3435 sigaddset(&check_signal_done, sig); 3436 } 3437 3438 // Dump all the signal 3439 if (sigismember(&check_signal_done, sig)) { 3440 print_signal_handlers(tty, buf, O_BUFLEN); 3441 } 3442 } 3443 3444 extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3445 3446 extern bool signal_name(int signo, char* buf, size_t len); 3447 3448 const char* os::exception_name(int exception_code, char* buf, size_t size) { 3449 if (0 < exception_code && exception_code <= SIGRTMAX) { 3450 // signal 3451 if (!signal_name(exception_code, buf, size)) { 3452 jio_snprintf(buf, size, "SIG%d", exception_code); 3453 } 3454 return buf; 3455 } else { 3456 return NULL; 3457 } 3458 } 3459 3460 // this is called _before_ the most of global arguments have been parsed 3461 void os::init(void) { 3462 char dummy; /* used to get a guess on initial stack address */ 3463 // first_hrtime = gethrtime(); 3464 3465 // With BsdThreads the JavaMain thread pid (primordial thread) 3466 // is different than the pid of the java launcher thread. 3467 // So, on Bsd, the launcher thread pid is passed to the VM 3468 // via the sun.java.launcher.pid property. 3469 // Use this property instead of getpid() if it was correctly passed. 3470 // See bug 6351349. 3471 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3472 3473 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3474 3475 clock_tics_per_sec = CLK_TCK; 3476 3477 init_random(1234567); 3478 3479 ThreadCritical::initialize(); 3480 3481 Bsd::set_page_size(getpagesize()); 3482 if (Bsd::page_size() == -1) { 3483 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3484 strerror(errno))); 3485 } 3486 init_page_sizes((size_t) Bsd::page_size()); 3487 3488 Bsd::initialize_system_info(); 3489 3490 // main_thread points to the aboriginal thread 3491 Bsd::_main_thread = pthread_self(); 3492 3493 Bsd::clock_init(); 3494 initial_time_count = javaTimeNanos(); 3495 3496 #ifdef __APPLE__ 3497 // XXXDARWIN 3498 // Work around the unaligned VM callbacks in hotspot's 3499 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3500 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3501 // alignment when doing symbol lookup. To work around this, we force early 3502 // binding of all symbols now, thus binding when alignment is known-good. 3503 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3504 #endif 3505 } 3506 3507 // To install functions for atexit system call 3508 extern "C" { 3509 static void perfMemory_exit_helper() { 3510 perfMemory_exit(); 3511 } 3512 } 3513 3514 // this is called _after_ the global arguments have been parsed 3515 jint os::init_2(void) 3516 { 3517 // Allocate a single page and mark it as readable for safepoint polling 3518 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3519 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3520 3521 os::set_polling_page(polling_page); 3522 3523 #ifndef PRODUCT 3524 if (Verbose && PrintMiscellaneous) 3525 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3526 #endif 3527 3528 if (!UseMembar) { 3529 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3530 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3531 os::set_memory_serialize_page(mem_serialize_page); 3532 3533 #ifndef PRODUCT 3534 if (Verbose && PrintMiscellaneous) 3535 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3536 #endif 3537 } 3538 3539 // initialize suspend/resume support - must do this before signal_sets_init() 3540 if (SR_initialize() != 0) { 3541 perror("SR_initialize failed"); 3542 return JNI_ERR; 3543 } 3544 3545 Bsd::signal_sets_init(); 3546 Bsd::install_signal_handlers(); 3547 3548 // Check minimum allowable stack size for thread creation and to initialize 3549 // the java system classes, including StackOverflowError - depends on page 3550 // size. Add a page for compiler2 recursion in main thread. 3551 // Add in 2*BytesPerWord times page size to account for VM stack during 3552 // class initialization depending on 32 or 64 bit VM. 3553 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3554 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3555 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3556 3557 size_t threadStackSizeInBytes = ThreadStackSize * K; 3558 if (threadStackSizeInBytes != 0 && 3559 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3560 tty->print_cr("\nThe stack size specified is too small, " 3561 "Specify at least %dk", 3562 os::Bsd::min_stack_allowed/ K); 3563 return JNI_ERR; 3564 } 3565 3566 // Make the stack size a multiple of the page size so that 3567 // the yellow/red zones can be guarded. 3568 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3569 vm_page_size())); 3570 3571 if (MaxFDLimit) { 3572 // set the number of file descriptors to max. print out error 3573 // if getrlimit/setrlimit fails but continue regardless. 3574 struct rlimit nbr_files; 3575 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3576 if (status != 0) { 3577 if (PrintMiscellaneous && (Verbose || WizardMode)) 3578 perror("os::init_2 getrlimit failed"); 3579 } else { 3580 nbr_files.rlim_cur = nbr_files.rlim_max; 3581 3582 #ifdef __APPLE__ 3583 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3584 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3585 // be used instead 3586 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3587 #endif 3588 3589 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3590 if (status != 0) { 3591 if (PrintMiscellaneous && (Verbose || WizardMode)) 3592 perror("os::init_2 setrlimit failed"); 3593 } 3594 } 3595 } 3596 3597 // at-exit methods are called in the reverse order of their registration. 3598 // atexit functions are called on return from main or as a result of a 3599 // call to exit(3C). There can be only 32 of these functions registered 3600 // and atexit() does not set errno. 3601 3602 if (PerfAllowAtExitRegistration) { 3603 // only register atexit functions if PerfAllowAtExitRegistration is set. 3604 // atexit functions can be delayed until process exit time, which 3605 // can be problematic for embedded VM situations. Embedded VMs should 3606 // call DestroyJavaVM() to assure that VM resources are released. 3607 3608 // note: perfMemory_exit_helper atexit function may be removed in 3609 // the future if the appropriate cleanup code can be added to the 3610 // VM_Exit VMOperation's doit method. 3611 if (atexit(perfMemory_exit_helper) != 0) { 3612 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3613 } 3614 } 3615 3616 // initialize thread priority policy 3617 prio_init(); 3618 3619 #ifdef __APPLE__ 3620 // dynamically link to objective c gc registration 3621 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3622 if (handleLibObjc != NULL) { 3623 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3624 } 3625 #endif 3626 3627 return JNI_OK; 3628 } 3629 3630 // this is called at the end of vm_initialization 3631 void os::init_3(void) { } 3632 3633 // Mark the polling page as unreadable 3634 void os::make_polling_page_unreadable(void) { 3635 if (!guard_memory((char*)_polling_page, Bsd::page_size())) 3636 fatal("Could not disable polling page"); 3637 }; 3638 3639 // Mark the polling page as readable 3640 void os::make_polling_page_readable(void) { 3641 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3642 fatal("Could not enable polling page"); 3643 } 3644 }; 3645 3646 int os::active_processor_count() { 3647 return _processor_count; 3648 } 3649 3650 void os::set_native_thread_name(const char *name) { 3651 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3652 // This is only supported in Snow Leopard and beyond 3653 if (name != NULL) { 3654 // Add a "Java: " prefix to the name 3655 char buf[MAXTHREADNAMESIZE]; 3656 snprintf(buf, sizeof(buf), "Java: %s", name); 3657 pthread_setname_np(buf); 3658 } 3659 #endif 3660 } 3661 3662 bool os::distribute_processes(uint length, uint* distribution) { 3663 // Not yet implemented. 3664 return false; 3665 } 3666 3667 bool os::bind_to_processor(uint processor_id) { 3668 // Not yet implemented. 3669 return false; 3670 } 3671 3672 void os::SuspendedThreadTask::internal_do_task() { 3673 if (do_suspend(_thread->osthread())) { 3674 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3675 do_task(context); 3676 do_resume(_thread->osthread()); 3677 } 3678 } 3679 3680 /// 3681 class PcFetcher : public os::SuspendedThreadTask { 3682 public: 3683 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3684 ExtendedPC result(); 3685 protected: 3686 void do_task(const os::SuspendedThreadTaskContext& context); 3687 private: 3688 ExtendedPC _epc; 3689 }; 3690 3691 ExtendedPC PcFetcher::result() { 3692 guarantee(is_done(), "task is not done yet."); 3693 return _epc; 3694 } 3695 3696 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3697 Thread* thread = context.thread(); 3698 OSThread* osthread = thread->osthread(); 3699 if (osthread->ucontext() != NULL) { 3700 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3701 } else { 3702 // NULL context is unexpected, double-check this is the VMThread 3703 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3704 } 3705 } 3706 3707 // Suspends the target using the signal mechanism and then grabs the PC before 3708 // resuming the target. Used by the flat-profiler only 3709 ExtendedPC os::get_thread_pc(Thread* thread) { 3710 // Make sure that it is called by the watcher for the VMThread 3711 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3712 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3713 3714 PcFetcher fetcher(thread); 3715 fetcher.run(); 3716 return fetcher.result(); 3717 } 3718 3719 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3720 { 3721 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3722 } 3723 3724 //////////////////////////////////////////////////////////////////////////////// 3725 // debug support 3726 3727 bool os::find(address addr, outputStream* st) { 3728 Dl_info dlinfo; 3729 memset(&dlinfo, 0, sizeof(dlinfo)); 3730 if (dladdr(addr, &dlinfo) != 0) { 3731 st->print(PTR_FORMAT ": ", addr); 3732 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3733 st->print("%s+%#x", dlinfo.dli_sname, 3734 addr - (intptr_t)dlinfo.dli_saddr); 3735 } else if (dlinfo.dli_fbase != NULL) { 3736 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3737 } else { 3738 st->print("<absolute address>"); 3739 } 3740 if (dlinfo.dli_fname != NULL) { 3741 st->print(" in %s", dlinfo.dli_fname); 3742 } 3743 if (dlinfo.dli_fbase != NULL) { 3744 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3745 } 3746 st->cr(); 3747 3748 if (Verbose) { 3749 // decode some bytes around the PC 3750 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3751 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3752 address lowest = (address) dlinfo.dli_sname; 3753 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3754 if (begin < lowest) begin = lowest; 3755 Dl_info dlinfo2; 3756 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3757 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3758 end = (address) dlinfo2.dli_saddr; 3759 Disassembler::decode(begin, end, st); 3760 } 3761 return true; 3762 } 3763 return false; 3764 } 3765 3766 //////////////////////////////////////////////////////////////////////////////// 3767 // misc 3768 3769 // This does not do anything on Bsd. This is basically a hook for being 3770 // able to use structured exception handling (thread-local exception filters) 3771 // on, e.g., Win32. 3772 void 3773 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3774 JavaCallArguments* args, Thread* thread) { 3775 f(value, method, args, thread); 3776 } 3777 3778 void os::print_statistics() { 3779 } 3780 3781 int os::message_box(const char* title, const char* message) { 3782 int i; 3783 fdStream err(defaultStream::error_fd()); 3784 for (i = 0; i < 78; i++) err.print_raw("="); 3785 err.cr(); 3786 err.print_raw_cr(title); 3787 for (i = 0; i < 78; i++) err.print_raw("-"); 3788 err.cr(); 3789 err.print_raw_cr(message); 3790 for (i = 0; i < 78; i++) err.print_raw("="); 3791 err.cr(); 3792 3793 char buf[16]; 3794 // Prevent process from exiting upon "read error" without consuming all CPU 3795 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3796 3797 return buf[0] == 'y' || buf[0] == 'Y'; 3798 } 3799 3800 int os::stat(const char *path, struct stat *sbuf) { 3801 char pathbuf[MAX_PATH]; 3802 if (strlen(path) > MAX_PATH - 1) { 3803 errno = ENAMETOOLONG; 3804 return -1; 3805 } 3806 os::native_path(strcpy(pathbuf, path)); 3807 return ::stat(pathbuf, sbuf); 3808 } 3809 3810 bool os::check_heap(bool force) { 3811 return true; 3812 } 3813 3814 ATTRIBUTE_PRINTF(3, 0) 3815 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 3816 return ::vsnprintf(buf, count, format, args); 3817 } 3818 3819 // Is a (classpath) directory empty? 3820 bool os::dir_is_empty(const char* path) { 3821 DIR *dir = NULL; 3822 struct dirent *ptr; 3823 3824 dir = opendir(path); 3825 if (dir == NULL) return true; 3826 3827 /* Scan the directory */ 3828 bool result = true; 3829 char buf[sizeof(struct dirent) + MAX_PATH]; 3830 while (result && (ptr = ::readdir(dir)) != NULL) { 3831 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3832 result = false; 3833 } 3834 } 3835 closedir(dir); 3836 return result; 3837 } 3838 3839 // This code originates from JDK's sysOpen and open64_w 3840 // from src/solaris/hpi/src/system_md.c 3841 3842 #ifndef O_DELETE 3843 #define O_DELETE 0x10000 3844 #endif 3845 3846 // Open a file. Unlink the file immediately after open returns 3847 // if the specified oflag has the O_DELETE flag set. 3848 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3849 3850 int os::open(const char *path, int oflag, int mode) { 3851 3852 if (strlen(path) > MAX_PATH - 1) { 3853 errno = ENAMETOOLONG; 3854 return -1; 3855 } 3856 int fd; 3857 int o_delete = (oflag & O_DELETE); 3858 oflag = oflag & ~O_DELETE; 3859 3860 fd = ::open(path, oflag, mode); 3861 if (fd == -1) return -1; 3862 3863 //If the open succeeded, the file might still be a directory 3864 { 3865 struct stat buf; 3866 int ret = ::fstat(fd, &buf); 3867 int st_mode = buf.st_mode; 3868 3869 if (ret != -1) { 3870 if ((st_mode & S_IFMT) == S_IFDIR) { 3871 errno = EISDIR; 3872 ::close(fd); 3873 return -1; 3874 } 3875 } else { 3876 ::close(fd); 3877 return -1; 3878 } 3879 } 3880 3881 /* 3882 * All file descriptors that are opened in the JVM and not 3883 * specifically destined for a subprocess should have the 3884 * close-on-exec flag set. If we don't set it, then careless 3rd 3885 * party native code might fork and exec without closing all 3886 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3887 * UNIXProcess.c), and this in turn might: 3888 * 3889 * - cause end-of-file to fail to be detected on some file 3890 * descriptors, resulting in mysterious hangs, or 3891 * 3892 * - might cause an fopen in the subprocess to fail on a system 3893 * suffering from bug 1085341. 3894 * 3895 * (Yes, the default setting of the close-on-exec flag is a Unix 3896 * design flaw) 3897 * 3898 * See: 3899 * 1085341: 32-bit stdio routines should support file descriptors >255 3900 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3901 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3902 */ 3903 #ifdef FD_CLOEXEC 3904 { 3905 int flags = ::fcntl(fd, F_GETFD); 3906 if (flags != -1) 3907 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3908 } 3909 #endif 3910 3911 if (o_delete != 0) { 3912 ::unlink(path); 3913 } 3914 return fd; 3915 } 3916 3917 3918 // create binary file, rewriting existing file if required 3919 int os::create_binary_file(const char* path, bool rewrite_existing) { 3920 int oflags = O_WRONLY | O_CREAT; 3921 if (!rewrite_existing) { 3922 oflags |= O_EXCL; 3923 } 3924 return ::open(path, oflags, S_IREAD | S_IWRITE); 3925 } 3926 3927 // return current position of file pointer 3928 jlong os::current_file_offset(int fd) { 3929 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3930 } 3931 3932 // move file pointer to the specified offset 3933 jlong os::seek_to_file_offset(int fd, jlong offset) { 3934 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3935 } 3936 3937 // This code originates from JDK's sysAvailable 3938 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3939 3940 int os::available(int fd, jlong *bytes) { 3941 jlong cur, end; 3942 int mode; 3943 struct stat buf; 3944 3945 if (::fstat(fd, &buf) >= 0) { 3946 mode = buf.st_mode; 3947 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3948 /* 3949 * XXX: is the following call interruptible? If so, this might 3950 * need to go through the INTERRUPT_IO() wrapper as for other 3951 * blocking, interruptible calls in this file. 3952 */ 3953 int n; 3954 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3955 *bytes = n; 3956 return 1; 3957 } 3958 } 3959 } 3960 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3961 return 0; 3962 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3963 return 0; 3964 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3965 return 0; 3966 } 3967 *bytes = end - cur; 3968 return 1; 3969 } 3970 3971 int os::socket_available(int fd, jint *pbytes) { 3972 if (fd < 0) 3973 return OS_OK; 3974 3975 int ret; 3976 3977 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 3978 3979 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 3980 // is expected to return 0 on failure and 1 on success to the jdk. 3981 3982 return (ret == OS_ERR) ? 0 : 1; 3983 } 3984 3985 // Map a block of memory. 3986 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3987 char *addr, size_t bytes, bool read_only, 3988 bool allow_exec) { 3989 int prot; 3990 int flags; 3991 3992 if (read_only) { 3993 prot = PROT_READ; 3994 flags = MAP_SHARED; 3995 } else { 3996 prot = PROT_READ | PROT_WRITE; 3997 flags = MAP_PRIVATE; 3998 } 3999 4000 if (allow_exec) { 4001 prot |= PROT_EXEC; 4002 } 4003 4004 if (addr != NULL) { 4005 flags |= MAP_FIXED; 4006 } 4007 4008 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4009 fd, file_offset); 4010 if (mapped_address == MAP_FAILED) { 4011 return NULL; 4012 } 4013 return mapped_address; 4014 } 4015 4016 4017 // Remap a block of memory. 4018 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4019 char *addr, size_t bytes, bool read_only, 4020 bool allow_exec) { 4021 // same as map_memory() on this OS 4022 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4023 allow_exec); 4024 } 4025 4026 4027 // Unmap a block of memory. 4028 bool os::pd_unmap_memory(char* addr, size_t bytes) { 4029 return munmap(addr, bytes) == 0; 4030 } 4031 4032 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4033 // are used by JVM M&M and JVMTI to get user+sys or user CPU time 4034 // of a thread. 4035 // 4036 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4037 // the fast estimate available on the platform. 4038 4039 jlong os::current_thread_cpu_time() { 4040 #ifdef __APPLE__ 4041 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4042 #else 4043 Unimplemented(); 4044 return 0; 4045 #endif 4046 } 4047 4048 jlong os::thread_cpu_time(Thread* thread) { 4049 #ifdef __APPLE__ 4050 return os::thread_cpu_time(thread, true /* user + sys */); 4051 #else 4052 Unimplemented(); 4053 return 0; 4054 #endif 4055 } 4056 4057 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4058 #ifdef __APPLE__ 4059 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4060 #else 4061 Unimplemented(); 4062 return 0; 4063 #endif 4064 } 4065 4066 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4067 #ifdef __APPLE__ 4068 struct thread_basic_info tinfo; 4069 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4070 kern_return_t kr; 4071 thread_t mach_thread; 4072 4073 mach_thread = thread->osthread()->thread_id(); 4074 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4075 if (kr != KERN_SUCCESS) 4076 return -1; 4077 4078 if (user_sys_cpu_time) { 4079 jlong nanos; 4080 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4081 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4082 return nanos; 4083 } else { 4084 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4085 } 4086 #else 4087 Unimplemented(); 4088 return 0; 4089 #endif 4090 } 4091 4092 4093 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4094 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4095 info_ptr->may_skip_backward = false; // elapsed time not wall time 4096 info_ptr->may_skip_forward = false; // elapsed time not wall time 4097 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4098 } 4099 4100 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4101 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4102 info_ptr->may_skip_backward = false; // elapsed time not wall time 4103 info_ptr->may_skip_forward = false; // elapsed time not wall time 4104 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4105 } 4106 4107 bool os::is_thread_cpu_time_supported() { 4108 #ifdef __APPLE__ 4109 return true; 4110 #else 4111 return false; 4112 #endif 4113 } 4114 4115 // System loadavg support. Returns -1 if load average cannot be obtained. 4116 // Bsd doesn't yet have a (official) notion of processor sets, 4117 // so just return the system wide load average. 4118 int os::loadavg(double loadavg[], int nelem) { 4119 return ::getloadavg(loadavg, nelem); 4120 } 4121 4122 void os::pause() { 4123 char filename[MAX_PATH]; 4124 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4125 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4126 } else { 4127 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4128 } 4129 4130 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4131 if (fd != -1) { 4132 struct stat buf; 4133 ::close(fd); 4134 while (::stat(filename, &buf) == 0) { 4135 (void)::poll(NULL, 0, 100); 4136 } 4137 } else { 4138 jio_fprintf(stderr, 4139 "Could not open pause file '%s', continuing immediately.\n", filename); 4140 } 4141 } 4142 4143 4144 // Refer to the comments in os_solaris.cpp park-unpark. 4145 // 4146 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4147 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4148 // For specifics regarding the bug see GLIBC BUGID 261237 : 4149 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4150 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4151 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4152 // is used. (The simple C test-case provided in the GLIBC bug report manifests the 4153 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4154 // and monitorenter when we're using 1-0 locking. All those operations may result in 4155 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4156 // of libpthread avoids the problem, but isn't practical. 4157 // 4158 // Possible remedies: 4159 // 4160 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4161 // This is palliative and probabilistic, however. If the thread is preempted 4162 // between the call to compute_abstime() and pthread_cond_timedwait(), more 4163 // than the minimum period may have passed, and the abstime may be stale (in the 4164 // past) resultin in a hang. Using this technique reduces the odds of a hang 4165 // but the JVM is still vulnerable, particularly on heavily loaded systems. 4166 // 4167 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4168 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4169 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4170 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4171 // thread. 4172 // 4173 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4174 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4175 // a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4176 // This also works well. In fact it avoids kernel-level scalability impediments 4177 // on certain platforms that don't handle lots of active pthread_cond_timedwait() 4178 // timers in a graceful fashion. 4179 // 4180 // 4. When the abstime value is in the past it appears that control returns 4181 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4182 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4183 // can avoid the problem by reinitializing the condvar -- by cond_destroy() 4184 // followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4185 // It may be possible to avoid reinitialization by checking the return 4186 // value from pthread_cond_timedwait(). In addition to reinitializing the 4187 // condvar we must establish the invariant that cond_signal() is only called 4188 // within critical sections protected by the adjunct mutex. This prevents 4189 // cond_signal() from "seeing" a condvar that's in the midst of being 4190 // reinitialized or that is corrupt. Sadly, this invariant obviates the 4191 // desirable signal-after-unlock optimization that avoids futile context switching. 4192 // 4193 // I'm also concerned that some versions of NTPL might allocate an auxilliary 4194 // structure when a condvar is used or initialized. cond_destroy() would 4195 // release the helper structure. Our reinitialize-after-timedwait fix 4196 // put excessive stress on malloc/free and locks protecting the c-heap. 4197 // 4198 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4199 // It may be possible to refine (4) by checking the kernel and NTPL verisons 4200 // and only enabling the work-around for vulnerable environments. 4201 4202 // utility to compute the abstime argument to timedwait: 4203 // millis is the relative timeout time 4204 // abstime will be the absolute timeout time 4205 // TODO: replace compute_abstime() with unpackTime() 4206 4207 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4208 if (millis < 0) millis = 0; 4209 struct timeval now; 4210 int status = gettimeofday(&now, NULL); 4211 assert(status == 0, "gettimeofday"); 4212 jlong seconds = millis / 1000; 4213 millis %= 1000; 4214 if (seconds > 50000000) { // see man cond_timedwait(3T) 4215 seconds = 50000000; 4216 } 4217 abstime->tv_sec = now.tv_sec + seconds; 4218 long usec = now.tv_usec + millis * 1000; 4219 if (usec >= 1000000) { 4220 abstime->tv_sec += 1; 4221 usec -= 1000000; 4222 } 4223 abstime->tv_nsec = usec * 1000; 4224 return abstime; 4225 } 4226 4227 4228 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 4229 // Conceptually TryPark() should be equivalent to park(0). 4230 4231 int os::PlatformEvent::TryPark() { 4232 for (;;) { 4233 const int v = _Event; 4234 guarantee((v == 0) || (v == 1), "invariant"); 4235 if (Atomic::cmpxchg(0, &_Event, v) == v) return v; 4236 } 4237 } 4238 4239 void os::PlatformEvent::park() { // AKA "down()" 4240 // Invariant: Only the thread associated with the Event/PlatformEvent 4241 // may call park(). 4242 // TODO: assert that _Assoc != NULL or _Assoc == Self 4243 int v; 4244 for (;;) { 4245 v = _Event; 4246 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4247 } 4248 guarantee(v >= 0, "invariant"); 4249 if (v == 0) { 4250 // Do this the hard way by blocking ... 4251 int status = pthread_mutex_lock(_mutex); 4252 assert_status(status == 0, status, "mutex_lock"); 4253 guarantee(_nParked == 0, "invariant"); 4254 ++_nParked; 4255 while (_Event < 0) { 4256 status = pthread_cond_wait(_cond, _mutex); 4257 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4258 // Treat this the same as if the wait was interrupted 4259 if (status == ETIMEDOUT) { status = EINTR; } 4260 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4261 } 4262 --_nParked; 4263 4264 _Event = 0; 4265 status = pthread_mutex_unlock(_mutex); 4266 assert_status(status == 0, status, "mutex_unlock"); 4267 // Paranoia to ensure our locked and lock-free paths interact 4268 // correctly with each other. 4269 OrderAccess::fence(); 4270 } 4271 guarantee(_Event >= 0, "invariant"); 4272 } 4273 4274 int os::PlatformEvent::park(jlong millis) { 4275 guarantee(_nParked == 0, "invariant"); 4276 4277 int v; 4278 for (;;) { 4279 v = _Event; 4280 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4281 } 4282 guarantee(v >= 0, "invariant"); 4283 if (v != 0) return OS_OK; 4284 4285 // We do this the hard way, by blocking the thread. 4286 // Consider enforcing a minimum timeout value. 4287 struct timespec abst; 4288 compute_abstime(&abst, millis); 4289 4290 int ret = OS_TIMEOUT; 4291 int status = pthread_mutex_lock(_mutex); 4292 assert_status(status == 0, status, "mutex_lock"); 4293 guarantee(_nParked == 0, "invariant"); 4294 ++_nParked; 4295 4296 // Object.wait(timo) will return because of 4297 // (a) notification 4298 // (b) timeout 4299 // (c) thread.interrupt 4300 // 4301 // Thread.interrupt and object.notify{All} both call Event::set. 4302 // That is, we treat thread.interrupt as a special case of notification. 4303 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4304 // We assume all ETIME returns are valid. 4305 // 4306 // TODO: properly differentiate simultaneous notify+interrupt. 4307 // In that case, we should propagate the notify to another waiter. 4308 4309 while (_Event < 0) { 4310 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4311 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4312 pthread_cond_destroy(_cond); 4313 pthread_cond_init(_cond, NULL); 4314 } 4315 assert_status(status == 0 || status == EINTR || 4316 status == ETIMEDOUT, 4317 status, "cond_timedwait"); 4318 if (!FilterSpuriousWakeups) break; // previous semantics 4319 if (status == ETIMEDOUT) break; 4320 // We consume and ignore EINTR and spurious wakeups. 4321 } 4322 --_nParked; 4323 if (_Event >= 0) { 4324 ret = OS_OK; 4325 } 4326 _Event = 0; 4327 status = pthread_mutex_unlock(_mutex); 4328 assert_status(status == 0, status, "mutex_unlock"); 4329 assert(_nParked == 0, "invariant"); 4330 // Paranoia to ensure our locked and lock-free paths interact 4331 // correctly with each other. 4332 OrderAccess::fence(); 4333 return ret; 4334 } 4335 4336 void os::PlatformEvent::unpark() { 4337 // Transitions for _Event: 4338 // 0 :=> 1 4339 // 1 :=> 1 4340 // -1 :=> either 0 or 1; must signal target thread 4341 // That is, we can safely transition _Event from -1 to either 4342 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back 4343 // unpark() calls. 4344 // See also: "Semaphores in Plan 9" by Mullender & Cox 4345 // 4346 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4347 // that it will take two back-to-back park() calls for the owning 4348 // thread to block. This has the benefit of forcing a spurious return 4349 // from the first park() call after an unpark() call which will help 4350 // shake out uses of park() and unpark() without condition variables. 4351 4352 if (Atomic::xchg(1, &_Event) >= 0) return; 4353 4354 // Wait for the thread associated with the event to vacate 4355 int status = pthread_mutex_lock(_mutex); 4356 assert_status(status == 0, status, "mutex_lock"); 4357 int AnyWaiters = _nParked; 4358 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4359 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4360 AnyWaiters = 0; 4361 pthread_cond_signal(_cond); 4362 } 4363 status = pthread_mutex_unlock(_mutex); 4364 assert_status(status == 0, status, "mutex_unlock"); 4365 if (AnyWaiters != 0) { 4366 status = pthread_cond_signal(_cond); 4367 assert_status(status == 0, status, "cond_signal"); 4368 } 4369 4370 // Note that we signal() _after dropping the lock for "immortal" Events. 4371 // This is safe and avoids a common class of futile wakeups. In rare 4372 // circumstances this can cause a thread to return prematurely from 4373 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4374 // simply re-test the condition and re-park itself. 4375 } 4376 4377 4378 // JSR166 4379 // ------------------------------------------------------- 4380 4381 /* 4382 * The solaris and bsd implementations of park/unpark are fairly 4383 * conservative for now, but can be improved. They currently use a 4384 * mutex/condvar pair, plus a a count. 4385 * Park decrements count if > 0, else does a condvar wait. Unpark 4386 * sets count to 1 and signals condvar. Only one thread ever waits 4387 * on the condvar. Contention seen when trying to park implies that someone 4388 * is unparking you, so don't wait. And spurious returns are fine, so there 4389 * is no need to track notifications. 4390 */ 4391 4392 #define MAX_SECS 100000000 4393 /* 4394 * This code is common to bsd and solaris and will be moved to a 4395 * common place in dolphin. 4396 * 4397 * The passed in time value is either a relative time in nanoseconds 4398 * or an absolute time in milliseconds. Either way it has to be unpacked 4399 * into suitable seconds and nanoseconds components and stored in the 4400 * given timespec structure. 4401 * Given time is a 64-bit value and the time_t used in the timespec is only 4402 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4403 * overflow if times way in the future are given. Further on Solaris versions 4404 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4405 * number of seconds, in abstime, is less than current_time + 100,000,000. 4406 * As it will be 28 years before "now + 100000000" will overflow we can 4407 * ignore overflow and just impose a hard-limit on seconds using the value 4408 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4409 * years from "now". 4410 */ 4411 4412 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4413 assert(time > 0, "convertTime"); 4414 4415 struct timeval now; 4416 int status = gettimeofday(&now, NULL); 4417 assert(status == 0, "gettimeofday"); 4418 4419 time_t max_secs = now.tv_sec + MAX_SECS; 4420 4421 if (isAbsolute) { 4422 jlong secs = time / 1000; 4423 if (secs > max_secs) { 4424 absTime->tv_sec = max_secs; 4425 } 4426 else { 4427 absTime->tv_sec = secs; 4428 } 4429 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4430 } 4431 else { 4432 jlong secs = time / NANOSECS_PER_SEC; 4433 if (secs >= MAX_SECS) { 4434 absTime->tv_sec = max_secs; 4435 absTime->tv_nsec = 0; 4436 } 4437 else { 4438 absTime->tv_sec = now.tv_sec + secs; 4439 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4440 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4441 absTime->tv_nsec -= NANOSECS_PER_SEC; 4442 ++absTime->tv_sec; // note: this must be <= max_secs 4443 } 4444 } 4445 } 4446 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4447 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4448 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4449 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4450 } 4451 4452 void Parker::park(bool isAbsolute, jlong time) { 4453 // Ideally we'd do something useful while spinning, such 4454 // as calling unpackTime(). 4455 4456 // Optional fast-path check: 4457 // Return immediately if a permit is available. 4458 // We depend on Atomic::xchg() having full barrier semantics 4459 // since we are doing a lock-free update to _counter. 4460 if (Atomic::xchg(0, &_counter) > 0) return; 4461 4462 Thread* thread = Thread::current(); 4463 assert(thread->is_Java_thread(), "Must be JavaThread"); 4464 JavaThread *jt = (JavaThread *)thread; 4465 4466 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4467 // Check interrupt before trying to wait 4468 if (Thread::is_interrupted(thread, false)) { 4469 return; 4470 } 4471 4472 // Next, demultiplex/decode time arguments 4473 struct timespec absTime; 4474 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4475 return; 4476 } 4477 if (time > 0) { 4478 unpackTime(&absTime, isAbsolute, time); 4479 } 4480 4481 4482 // Enter safepoint region 4483 // Beware of deadlocks such as 6317397. 4484 // The per-thread Parker:: mutex is a classic leaf-lock. 4485 // In particular a thread must never block on the Threads_lock while 4486 // holding the Parker:: mutex. If safepoints are pending both the 4487 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4488 ThreadBlockInVM tbivm(jt); 4489 4490 // Don't wait if cannot get lock since interference arises from 4491 // unblocking. Also. check interrupt before trying wait 4492 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4493 return; 4494 } 4495 4496 int status; 4497 if (_counter > 0) { // no wait needed 4498 _counter = 0; 4499 status = pthread_mutex_unlock(_mutex); 4500 assert(status == 0, "invariant"); 4501 // Paranoia to ensure our locked and lock-free paths interact 4502 // correctly with each other and Java-level accesses. 4503 OrderAccess::fence(); 4504 return; 4505 } 4506 4507 #ifdef ASSERT 4508 // Don't catch signals while blocked; let the running threads have the signals. 4509 // (This allows a debugger to break into the running thread.) 4510 sigset_t oldsigs; 4511 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4512 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4513 #endif 4514 4515 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4516 jt->set_suspend_equivalent(); 4517 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4518 4519 if (time == 0) { 4520 status = pthread_cond_wait(_cond, _mutex); 4521 } else { 4522 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &absTime); 4523 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4524 pthread_cond_destroy(_cond); 4525 pthread_cond_init(_cond, NULL); 4526 } 4527 } 4528 assert_status(status == 0 || status == EINTR || 4529 status == ETIMEDOUT, 4530 status, "cond_timedwait"); 4531 4532 #ifdef ASSERT 4533 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4534 #endif 4535 4536 _counter = 0; 4537 status = pthread_mutex_unlock(_mutex); 4538 assert_status(status == 0, status, "invariant"); 4539 // Paranoia to ensure our locked and lock-free paths interact 4540 // correctly with each other and Java-level accesses. 4541 OrderAccess::fence(); 4542 4543 // If externally suspended while waiting, re-suspend 4544 if (jt->handle_special_suspend_equivalent_condition()) { 4545 jt->java_suspend_self(); 4546 } 4547 } 4548 4549 void Parker::unpark() { 4550 int s, status; 4551 status = pthread_mutex_lock(_mutex); 4552 assert(status == 0, "invariant"); 4553 s = _counter; 4554 _counter = 1; 4555 if (s < 1) { 4556 if (WorkAroundNPTLTimedWaitHang) { 4557 status = pthread_cond_signal(_cond); 4558 assert(status == 0, "invariant"); 4559 status = pthread_mutex_unlock(_mutex); 4560 assert(status == 0, "invariant"); 4561 } else { 4562 status = pthread_mutex_unlock(_mutex); 4563 assert(status == 0, "invariant"); 4564 status = pthread_cond_signal(_cond); 4565 assert(status == 0, "invariant"); 4566 } 4567 } else { 4568 pthread_mutex_unlock(_mutex); 4569 assert(status == 0, "invariant"); 4570 } 4571 } 4572 4573 4574 /* Darwin has no "environ" in a dynamic library. */ 4575 #ifdef __APPLE__ 4576 #include <crt_externs.h> 4577 #define environ (*_NSGetEnviron()) 4578 #else 4579 extern char** environ; 4580 #endif 4581 4582 // Run the specified command in a separate process. Return its exit value, 4583 // or -1 on failure (e.g. can't fork a new process). 4584 // Unlike system(), this function can be called from signal handler. It 4585 // doesn't block SIGINT et al. 4586 int os::fork_and_exec(char* cmd) { 4587 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4588 4589 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4590 // pthread_atfork handlers and reset pthread library. All we need is a 4591 // separate process to execve. Make a direct syscall to fork process. 4592 // On IA64 there's no fork syscall, we have to use fork() and hope for 4593 // the best... 4594 pid_t pid = fork(); 4595 4596 if (pid < 0) { 4597 // fork failed 4598 return -1; 4599 4600 } else if (pid == 0) { 4601 // child process 4602 4603 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4604 // first to kill every thread on the thread list. Because this list is 4605 // not reset by fork() (see notes above), execve() will instead kill 4606 // every thread in the parent process. We know this is the only thread 4607 // in the new process, so make a system call directly. 4608 // IA64 should use normal execve() from glibc to match the glibc fork() 4609 // above. 4610 execve("/bin/sh", (char* const*)argv, environ); 4611 4612 // execve failed 4613 _exit(-1); 4614 4615 } else { 4616 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4617 // care about the actual exit code, for now. 4618 4619 int status; 4620 4621 // Wait for the child process to exit. This returns immediately if 4622 // the child has already exited. */ 4623 while (waitpid(pid, &status, 0) < 0) { 4624 switch (errno) { 4625 case ECHILD: return 0; 4626 case EINTR: break; 4627 default: return -1; 4628 } 4629 } 4630 4631 if (WIFEXITED(status)) { 4632 // The child exited normally; get its exit code. 4633 return WEXITSTATUS(status); 4634 } else if (WIFSIGNALED(status)) { 4635 // The child exited because of a signal 4636 // The best value to return is 0x80 + signal number, 4637 // because that is what all Unix shells do, and because 4638 // it allows callers to distinguish between process exit and 4639 // process death by signal. 4640 return 0x80 + WTERMSIG(status); 4641 } else { 4642 // Unknown exit code; pass it through 4643 return status; 4644 } 4645 } 4646 } 4647 4648 // is_headless_jre() 4649 // 4650 // Test for the existence of xawt/libmawt.so or libawt_xawt.so 4651 // in order to report if we are running in a headless jre 4652 // 4653 // Since JDK8 xawt/libmawt.so was moved into the same directory 4654 // as libawt.so, and renamed libawt_xawt.so 4655 // 4656 bool os::is_headless_jre() { 4657 #ifdef __APPLE__ 4658 // We no longer build headless-only on Mac OS X 4659 return false; 4660 #else 4661 struct stat statbuf; 4662 char buf[MAXPATHLEN]; 4663 char libmawtpath[MAXPATHLEN]; 4664 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4665 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4666 char *p; 4667 4668 // Get path to libjvm.so 4669 os::jvm_path(buf, sizeof(buf)); 4670 4671 // Get rid of libjvm.so 4672 p = strrchr(buf, '/'); 4673 if (p == NULL) return false; 4674 else *p = '\0'; 4675 4676 // Get rid of client or server 4677 p = strrchr(buf, '/'); 4678 if (p == NULL) return false; 4679 else *p = '\0'; 4680 4681 // check xawt/libmawt.so 4682 strcpy(libmawtpath, buf); 4683 strcat(libmawtpath, xawtstr); 4684 if (::stat(libmawtpath, &statbuf) == 0) return false; 4685 4686 // check libawt_xawt.so 4687 strcpy(libmawtpath, buf); 4688 strcat(libmawtpath, new_xawtstr); 4689 if (::stat(libmawtpath, &statbuf) == 0) return false; 4690 4691 return true; 4692 #endif 4693 } 4694 4695 // Get the default path to the core file 4696 // Returns the length of the string 4697 int os::get_core_path(char* buffer, size_t bufferSize) { 4698 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4699 4700 // Truncate if theoretical string was longer than bufferSize 4701 n = MIN2(n, (int)bufferSize); 4702 4703 return n; 4704 } 4705 4706 #ifndef PRODUCT 4707 void TestReserveMemorySpecial_test() { 4708 // No tests available for this platform 4709 } 4710 #endif