os_bsd.cpp revision 8225:eb02bcd73927
1/* 2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25// no precompiled headers 26#include "classfile/classLoader.hpp" 27#include "classfile/systemDictionary.hpp" 28#include "classfile/vmSymbols.hpp" 29#include "code/icBuffer.hpp" 30#include "code/vtableStubs.hpp" 31#include "compiler/compileBroker.hpp" 32#include "compiler/disassembler.hpp" 33#include "interpreter/interpreter.hpp" 34#include "jvm_bsd.h" 35#include "memory/allocation.inline.hpp" 36#include "memory/filemap.hpp" 37#include "mutex_bsd.inline.hpp" 38#include "oops/oop.inline.hpp" 39#include "os_bsd.inline.hpp" 40#include "os_share_bsd.hpp" 41#include "prims/jniFastGetField.hpp" 42#include "prims/jvm.h" 43#include "prims/jvm_misc.hpp" 44#include "runtime/arguments.hpp" 45#include "runtime/atomic.inline.hpp" 46#include "runtime/extendedPC.hpp" 47#include "runtime/globals.hpp" 48#include "runtime/interfaceSupport.hpp" 49#include "runtime/java.hpp" 50#include "runtime/javaCalls.hpp" 51#include "runtime/mutexLocker.hpp" 52#include "runtime/objectMonitor.hpp" 53#include "runtime/orderAccess.inline.hpp" 54#include "runtime/osThread.hpp" 55#include "runtime/perfMemory.hpp" 56#include "runtime/sharedRuntime.hpp" 57#include "runtime/statSampler.hpp" 58#include "runtime/stubRoutines.hpp" 59#include "runtime/thread.inline.hpp" 60#include "runtime/threadCritical.hpp" 61#include "runtime/timer.hpp" 62#include "services/attachListener.hpp" 63#include "services/memTracker.hpp" 64#include "services/runtimeService.hpp" 65#include "utilities/decoder.hpp" 66#include "utilities/defaultStream.hpp" 67#include "utilities/events.hpp" 68#include "utilities/growableArray.hpp" 69#include "utilities/vmError.hpp" 70 71// put OS-includes here 72# include <sys/types.h> 73# include <sys/mman.h> 74# include <sys/stat.h> 75# include <sys/select.h> 76# include <pthread.h> 77# include <signal.h> 78# include <errno.h> 79# include <dlfcn.h> 80# include <stdio.h> 81# include <unistd.h> 82# include <sys/resource.h> 83# include <pthread.h> 84# include <sys/stat.h> 85# include <sys/time.h> 86# include <sys/times.h> 87# include <sys/utsname.h> 88# include <sys/socket.h> 89# include <sys/wait.h> 90# include <time.h> 91# include <pwd.h> 92# include <poll.h> 93# include <semaphore.h> 94# include <fcntl.h> 95# include <string.h> 96# include <sys/param.h> 97# include <sys/sysctl.h> 98# include <sys/ipc.h> 99# include <sys/shm.h> 100#ifndef __APPLE__ 101# include <link.h> 102#endif 103# include <stdint.h> 104# include <inttypes.h> 105# include <sys/ioctl.h> 106# include <sys/syscall.h> 107 108#if defined(__FreeBSD__) || defined(__NetBSD__) 109 #include <elf.h> 110#endif 111 112#ifdef __APPLE__ 113 #include <mach/mach.h> // semaphore_* API 114 #include <mach-o/dyld.h> 115 #include <sys/proc_info.h> 116 #include <objc/objc-auto.h> 117#endif 118 119#ifndef MAP_ANONYMOUS 120 #define MAP_ANONYMOUS MAP_ANON 121#endif 122 123#define MAX_PATH (2 * K) 124 125// for timer info max values which include all bits 126#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 127 128#define LARGEPAGES_BIT (1 << 6) 129 130PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 131 132//////////////////////////////////////////////////////////////////////////////// 133// global variables 134julong os::Bsd::_physical_memory = 0; 135 136#ifdef __APPLE__ 137mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 138volatile uint64_t os::Bsd::_max_abstime = 0; 139#else 140int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 141#endif 142pthread_t os::Bsd::_main_thread; 143int os::Bsd::_page_size = -1; 144 145static jlong initial_time_count=0; 146 147static int clock_tics_per_sec = 100; 148 149// For diagnostics to print a message once. see run_periodic_checks 150static sigset_t check_signal_done; 151static bool check_signals = true; 152 153static pid_t _initial_pid = 0; 154 155// Signal number used to suspend/resume a thread 156 157// do not use any signal number less than SIGSEGV, see 4355769 158static int SR_signum = SIGUSR2; 159sigset_t SR_sigset; 160 161 162//////////////////////////////////////////////////////////////////////////////// 163// utility functions 164 165static int SR_initialize(); 166static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 167 168julong os::available_memory() { 169 return Bsd::available_memory(); 170} 171 172// available here means free 173julong os::Bsd::available_memory() { 174 uint64_t available = physical_memory() >> 2; 175#ifdef __APPLE__ 176 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 177 vm_statistics64_data_t vmstat; 178 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 179 (host_info64_t)&vmstat, &count); 180 assert(kerr == KERN_SUCCESS, 181 "host_statistics64 failed - check mach_host_self() and count"); 182 if (kerr == KERN_SUCCESS) { 183 available = vmstat.free_count * os::vm_page_size(); 184 } 185#endif 186 return available; 187} 188 189julong os::physical_memory() { 190 return Bsd::physical_memory(); 191} 192 193// Return true if user is running as root. 194 195bool os::have_special_privileges() { 196 static bool init = false; 197 static bool privileges = false; 198 if (!init) { 199 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 200 init = true; 201 } 202 return privileges; 203} 204 205 206 207// Cpu architecture string 208#if defined(ZERO) 209static char cpu_arch[] = ZERO_LIBARCH; 210#elif defined(IA64) 211static char cpu_arch[] = "ia64"; 212#elif defined(IA32) 213static char cpu_arch[] = "i386"; 214#elif defined(AMD64) 215static char cpu_arch[] = "amd64"; 216#elif defined(ARM) 217static char cpu_arch[] = "arm"; 218#elif defined(PPC32) 219static char cpu_arch[] = "ppc"; 220#elif defined(SPARC) 221 #ifdef _LP64 222static char cpu_arch[] = "sparcv9"; 223 #else 224static char cpu_arch[] = "sparc"; 225 #endif 226#else 227 #error Add appropriate cpu_arch setting 228#endif 229 230// Compiler variant 231#ifdef COMPILER2 232 #define COMPILER_VARIANT "server" 233#else 234 #define COMPILER_VARIANT "client" 235#endif 236 237 238void os::Bsd::initialize_system_info() { 239 int mib[2]; 240 size_t len; 241 int cpu_val; 242 julong mem_val; 243 244 // get processors count via hw.ncpus sysctl 245 mib[0] = CTL_HW; 246 mib[1] = HW_NCPU; 247 len = sizeof(cpu_val); 248 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 249 assert(len == sizeof(cpu_val), "unexpected data size"); 250 set_processor_count(cpu_val); 251 } else { 252 set_processor_count(1); // fallback 253 } 254 255 // get physical memory via hw.memsize sysctl (hw.memsize is used 256 // since it returns a 64 bit value) 257 mib[0] = CTL_HW; 258 259#if defined (HW_MEMSIZE) // Apple 260 mib[1] = HW_MEMSIZE; 261#elif defined(HW_PHYSMEM) // Most of BSD 262 mib[1] = HW_PHYSMEM; 263#elif defined(HW_REALMEM) // Old FreeBSD 264 mib[1] = HW_REALMEM; 265#else 266 #error No ways to get physmem 267#endif 268 269 len = sizeof(mem_val); 270 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 271 assert(len == sizeof(mem_val), "unexpected data size"); 272 _physical_memory = mem_val; 273 } else { 274 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 275 } 276 277#ifdef __OpenBSD__ 278 { 279 // limit _physical_memory memory view on OpenBSD since 280 // datasize rlimit restricts us anyway. 281 struct rlimit limits; 282 getrlimit(RLIMIT_DATA, &limits); 283 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 284 } 285#endif 286} 287 288#ifdef __APPLE__ 289static const char *get_home() { 290 const char *home_dir = ::getenv("HOME"); 291 if ((home_dir == NULL) || (*home_dir == '\0')) { 292 struct passwd *passwd_info = getpwuid(geteuid()); 293 if (passwd_info != NULL) { 294 home_dir = passwd_info->pw_dir; 295 } 296 } 297 298 return home_dir; 299} 300#endif 301 302void os::init_system_properties_values() { 303 // The next steps are taken in the product version: 304 // 305 // Obtain the JAVA_HOME value from the location of libjvm.so. 306 // This library should be located at: 307 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 308 // 309 // If "/jre/lib/" appears at the right place in the path, then we 310 // assume libjvm.so is installed in a JDK and we use this path. 311 // 312 // Otherwise exit with message: "Could not create the Java virtual machine." 313 // 314 // The following extra steps are taken in the debugging version: 315 // 316 // If "/jre/lib/" does NOT appear at the right place in the path 317 // instead of exit check for $JAVA_HOME environment variable. 318 // 319 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 320 // then we append a fake suffix "hotspot/libjvm.so" to this path so 321 // it looks like libjvm.so is installed there 322 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 323 // 324 // Otherwise exit. 325 // 326 // Important note: if the location of libjvm.so changes this 327 // code needs to be changed accordingly. 328 329 // See ld(1): 330 // The linker uses the following search paths to locate required 331 // shared libraries: 332 // 1: ... 333 // ... 334 // 7: The default directories, normally /lib and /usr/lib. 335#ifndef DEFAULT_LIBPATH 336 #define DEFAULT_LIBPATH "/lib:/usr/lib" 337#endif 338 339// Base path of extensions installed on the system. 340#define SYS_EXT_DIR "/usr/java/packages" 341#define EXTENSIONS_DIR "/lib/ext" 342 343#ifndef __APPLE__ 344 345 // Buffer that fits several sprintfs. 346 // Note that the space for the colon and the trailing null are provided 347 // by the nulls included by the sizeof operator. 348 const size_t bufsize = 349 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 350 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 351 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 352 353 // sysclasspath, java_home, dll_dir 354 { 355 char *pslash; 356 os::jvm_path(buf, bufsize); 357 358 // Found the full path to libjvm.so. 359 // Now cut the path to <java_home>/jre if we can. 360 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 361 pslash = strrchr(buf, '/'); 362 if (pslash != NULL) { 363 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 364 } 365 Arguments::set_dll_dir(buf); 366 367 if (pslash != NULL) { 368 pslash = strrchr(buf, '/'); 369 if (pslash != NULL) { 370 *pslash = '\0'; // Get rid of /<arch>. 371 pslash = strrchr(buf, '/'); 372 if (pslash != NULL) { 373 *pslash = '\0'; // Get rid of /lib. 374 } 375 } 376 } 377 Arguments::set_java_home(buf); 378 set_boot_path('/', ':'); 379 } 380 381 // Where to look for native libraries. 382 // 383 // Note: Due to a legacy implementation, most of the library path 384 // is set in the launcher. This was to accomodate linking restrictions 385 // on legacy Bsd implementations (which are no longer supported). 386 // Eventually, all the library path setting will be done here. 387 // 388 // However, to prevent the proliferation of improperly built native 389 // libraries, the new path component /usr/java/packages is added here. 390 // Eventually, all the library path setting will be done here. 391 { 392 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 393 // should always exist (until the legacy problem cited above is 394 // addressed). 395 const char *v = ::getenv("LD_LIBRARY_PATH"); 396 const char *v_colon = ":"; 397 if (v == NULL) { v = ""; v_colon = ""; } 398 // That's +1 for the colon and +1 for the trailing '\0'. 399 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 400 strlen(v) + 1 + 401 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 402 mtInternal); 403 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 404 Arguments::set_library_path(ld_library_path); 405 FREE_C_HEAP_ARRAY(char, ld_library_path); 406 } 407 408 // Extensions directories. 409 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 410 Arguments::set_ext_dirs(buf); 411 412 FREE_C_HEAP_ARRAY(char, buf); 413 414#else // __APPLE__ 415 416 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 417 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 418 419 const char *user_home_dir = get_home(); 420 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 421 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 422 sizeof(SYS_EXTENSIONS_DIRS); 423 424 // Buffer that fits several sprintfs. 425 // Note that the space for the colon and the trailing null are provided 426 // by the nulls included by the sizeof operator. 427 const size_t bufsize = 428 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 429 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 430 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 431 432 // sysclasspath, java_home, dll_dir 433 { 434 char *pslash; 435 os::jvm_path(buf, bufsize); 436 437 // Found the full path to libjvm.so. 438 // Now cut the path to <java_home>/jre if we can. 439 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 440 pslash = strrchr(buf, '/'); 441 if (pslash != NULL) { 442 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 443 } 444 Arguments::set_dll_dir(buf); 445 446 if (pslash != NULL) { 447 pslash = strrchr(buf, '/'); 448 if (pslash != NULL) { 449 *pslash = '\0'; // Get rid of /lib. 450 } 451 } 452 Arguments::set_java_home(buf); 453 set_boot_path('/', ':'); 454 } 455 456 // Where to look for native libraries. 457 // 458 // Note: Due to a legacy implementation, most of the library path 459 // is set in the launcher. This was to accomodate linking restrictions 460 // on legacy Bsd implementations (which are no longer supported). 461 // Eventually, all the library path setting will be done here. 462 // 463 // However, to prevent the proliferation of improperly built native 464 // libraries, the new path component /usr/java/packages is added here. 465 // Eventually, all the library path setting will be done here. 466 { 467 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 468 // should always exist (until the legacy problem cited above is 469 // addressed). 470 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 471 // can specify a directory inside an app wrapper 472 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 473 const char *l_colon = ":"; 474 if (l == NULL) { l = ""; l_colon = ""; } 475 476 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 477 const char *v_colon = ":"; 478 if (v == NULL) { v = ""; v_colon = ""; } 479 480 // Apple's Java6 has "." at the beginning of java.library.path. 481 // OpenJDK on Windows has "." at the end of java.library.path. 482 // OpenJDK on Linux and Solaris don't have "." in java.library.path 483 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 484 // "." is appended to the end of java.library.path. Yes, this 485 // could cause a change in behavior, but Apple's Java6 behavior 486 // can be achieved by putting "." at the beginning of the 487 // JAVA_LIBRARY_PATH environment variable. 488 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 489 strlen(v) + 1 + strlen(l) + 1 + 490 system_ext_size + 3, 491 mtInternal); 492 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 493 v, v_colon, l, l_colon, user_home_dir); 494 Arguments::set_library_path(ld_library_path); 495 FREE_C_HEAP_ARRAY(char, ld_library_path); 496 } 497 498 // Extensions directories. 499 // 500 // Note that the space for the colon and the trailing null are provided 501 // by the nulls included by the sizeof operator (so actually one byte more 502 // than necessary is allocated). 503 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 504 user_home_dir, Arguments::get_java_home()); 505 Arguments::set_ext_dirs(buf); 506 507 FREE_C_HEAP_ARRAY(char, buf); 508 509#undef SYS_EXTENSIONS_DIR 510#undef SYS_EXTENSIONS_DIRS 511 512#endif // __APPLE__ 513 514#undef SYS_EXT_DIR 515#undef EXTENSIONS_DIR 516} 517 518//////////////////////////////////////////////////////////////////////////////// 519// breakpoint support 520 521void os::breakpoint() { 522 BREAKPOINT; 523} 524 525extern "C" void breakpoint() { 526 // use debugger to set breakpoint here 527} 528 529//////////////////////////////////////////////////////////////////////////////// 530// signal support 531 532debug_only(static bool signal_sets_initialized = false); 533static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 534 535bool os::Bsd::is_sig_ignored(int sig) { 536 struct sigaction oact; 537 sigaction(sig, (struct sigaction*)NULL, &oact); 538 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 539 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 540 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) { 541 return true; 542 } else { 543 return false; 544 } 545} 546 547void os::Bsd::signal_sets_init() { 548 // Should also have an assertion stating we are still single-threaded. 549 assert(!signal_sets_initialized, "Already initialized"); 550 // Fill in signals that are necessarily unblocked for all threads in 551 // the VM. Currently, we unblock the following signals: 552 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 553 // by -Xrs (=ReduceSignalUsage)); 554 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 555 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 556 // the dispositions or masks wrt these signals. 557 // Programs embedding the VM that want to use the above signals for their 558 // own purposes must, at this time, use the "-Xrs" option to prevent 559 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 560 // (See bug 4345157, and other related bugs). 561 // In reality, though, unblocking these signals is really a nop, since 562 // these signals are not blocked by default. 563 sigemptyset(&unblocked_sigs); 564 sigemptyset(&allowdebug_blocked_sigs); 565 sigaddset(&unblocked_sigs, SIGILL); 566 sigaddset(&unblocked_sigs, SIGSEGV); 567 sigaddset(&unblocked_sigs, SIGBUS); 568 sigaddset(&unblocked_sigs, SIGFPE); 569 sigaddset(&unblocked_sigs, SR_signum); 570 571 if (!ReduceSignalUsage) { 572 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 573 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 574 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 575 } 576 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 577 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 578 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 579 } 580 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 581 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 582 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 583 } 584 } 585 // Fill in signals that are blocked by all but the VM thread. 586 sigemptyset(&vm_sigs); 587 if (!ReduceSignalUsage) { 588 sigaddset(&vm_sigs, BREAK_SIGNAL); 589 } 590 debug_only(signal_sets_initialized = true); 591 592} 593 594// These are signals that are unblocked while a thread is running Java. 595// (For some reason, they get blocked by default.) 596sigset_t* os::Bsd::unblocked_signals() { 597 assert(signal_sets_initialized, "Not initialized"); 598 return &unblocked_sigs; 599} 600 601// These are the signals that are blocked while a (non-VM) thread is 602// running Java. Only the VM thread handles these signals. 603sigset_t* os::Bsd::vm_signals() { 604 assert(signal_sets_initialized, "Not initialized"); 605 return &vm_sigs; 606} 607 608// These are signals that are blocked during cond_wait to allow debugger in 609sigset_t* os::Bsd::allowdebug_blocked_signals() { 610 assert(signal_sets_initialized, "Not initialized"); 611 return &allowdebug_blocked_sigs; 612} 613 614void os::Bsd::hotspot_sigmask(Thread* thread) { 615 616 //Save caller's signal mask before setting VM signal mask 617 sigset_t caller_sigmask; 618 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 619 620 OSThread* osthread = thread->osthread(); 621 osthread->set_caller_sigmask(caller_sigmask); 622 623 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 624 625 if (!ReduceSignalUsage) { 626 if (thread->is_VM_thread()) { 627 // Only the VM thread handles BREAK_SIGNAL ... 628 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 629 } else { 630 // ... all other threads block BREAK_SIGNAL 631 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 632 } 633 } 634} 635 636 637////////////////////////////////////////////////////////////////////////////// 638// create new thread 639 640// check if it's safe to start a new thread 641static bool _thread_safety_check(Thread* thread) { 642 return true; 643} 644 645#ifdef __APPLE__ 646// library handle for calling objc_registerThreadWithCollector() 647// without static linking to the libobjc library 648 #define OBJC_LIB "/usr/lib/libobjc.dylib" 649 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 650typedef void (*objc_registerThreadWithCollector_t)(); 651extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 652objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 653#endif 654 655#ifdef __APPLE__ 656static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 657 // Additional thread_id used to correlate threads in SA 658 thread_identifier_info_data_t m_ident_info; 659 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 660 661 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 662 (thread_info_t) &m_ident_info, &count); 663 664 return m_ident_info.thread_id; 665} 666#endif 667 668// Thread start routine for all newly created threads 669static void *java_start(Thread *thread) { 670 // Try to randomize the cache line index of hot stack frames. 671 // This helps when threads of the same stack traces evict each other's 672 // cache lines. The threads can be either from the same JVM instance, or 673 // from different JVM instances. The benefit is especially true for 674 // processors with hyperthreading technology. 675 static int counter = 0; 676 int pid = os::current_process_id(); 677 alloca(((pid ^ counter++) & 7) * 128); 678 679 ThreadLocalStorage::set_thread(thread); 680 681 OSThread* osthread = thread->osthread(); 682 Monitor* sync = osthread->startThread_lock(); 683 684 // non floating stack BsdThreads needs extra check, see above 685 if (!_thread_safety_check(thread)) { 686 // notify parent thread 687 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 688 osthread->set_state(ZOMBIE); 689 sync->notify_all(); 690 return NULL; 691 } 692 693 osthread->set_thread_id(os::Bsd::gettid()); 694 695#ifdef __APPLE__ 696 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 697 guarantee(unique_thread_id != 0, "unique thread id was not found"); 698 osthread->set_unique_thread_id(unique_thread_id); 699#endif 700 // initialize signal mask for this thread 701 os::Bsd::hotspot_sigmask(thread); 702 703 // initialize floating point control register 704 os::Bsd::init_thread_fpu_state(); 705 706#ifdef __APPLE__ 707 // register thread with objc gc 708 if (objc_registerThreadWithCollectorFunction != NULL) { 709 objc_registerThreadWithCollectorFunction(); 710 } 711#endif 712 713 // handshaking with parent thread 714 { 715 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 716 717 // notify parent thread 718 osthread->set_state(INITIALIZED); 719 sync->notify_all(); 720 721 // wait until os::start_thread() 722 while (osthread->get_state() == INITIALIZED) { 723 sync->wait(Mutex::_no_safepoint_check_flag); 724 } 725 } 726 727 // call one more level start routine 728 thread->run(); 729 730 return 0; 731} 732 733bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 734 assert(thread->osthread() == NULL, "caller responsible"); 735 736 // Allocate the OSThread object 737 OSThread* osthread = new OSThread(NULL, NULL); 738 if (osthread == NULL) { 739 return false; 740 } 741 742 // set the correct thread state 743 osthread->set_thread_type(thr_type); 744 745 // Initial state is ALLOCATED but not INITIALIZED 746 osthread->set_state(ALLOCATED); 747 748 thread->set_osthread(osthread); 749 750 // init thread attributes 751 pthread_attr_t attr; 752 pthread_attr_init(&attr); 753 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 754 755 // stack size 756 if (os::Bsd::supports_variable_stack_size()) { 757 // calculate stack size if it's not specified by caller 758 if (stack_size == 0) { 759 stack_size = os::Bsd::default_stack_size(thr_type); 760 761 switch (thr_type) { 762 case os::java_thread: 763 // Java threads use ThreadStackSize which default value can be 764 // changed with the flag -Xss 765 assert(JavaThread::stack_size_at_create() > 0, "this should be set"); 766 stack_size = JavaThread::stack_size_at_create(); 767 break; 768 case os::compiler_thread: 769 if (CompilerThreadStackSize > 0) { 770 stack_size = (size_t)(CompilerThreadStackSize * K); 771 break; 772 } // else fall through: 773 // use VMThreadStackSize if CompilerThreadStackSize is not defined 774 case os::vm_thread: 775 case os::pgc_thread: 776 case os::cgc_thread: 777 case os::watcher_thread: 778 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 779 break; 780 } 781 } 782 783 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 784 pthread_attr_setstacksize(&attr, stack_size); 785 } else { 786 // let pthread_create() pick the default value. 787 } 788 789 ThreadState state; 790 791 { 792 pthread_t tid; 793 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 794 795 pthread_attr_destroy(&attr); 796 797 if (ret != 0) { 798 if (PrintMiscellaneous && (Verbose || WizardMode)) { 799 perror("pthread_create()"); 800 } 801 // Need to clean up stuff we've allocated so far 802 thread->set_osthread(NULL); 803 delete osthread; 804 return false; 805 } 806 807 // Store pthread info into the OSThread 808 osthread->set_pthread_id(tid); 809 810 // Wait until child thread is either initialized or aborted 811 { 812 Monitor* sync_with_child = osthread->startThread_lock(); 813 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 814 while ((state = osthread->get_state()) == ALLOCATED) { 815 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 816 } 817 } 818 819 } 820 821 // Aborted due to thread limit being reached 822 if (state == ZOMBIE) { 823 thread->set_osthread(NULL); 824 delete osthread; 825 return false; 826 } 827 828 // The thread is returned suspended (in state INITIALIZED), 829 // and is started higher up in the call chain 830 assert(state == INITIALIZED, "race condition"); 831 return true; 832} 833 834///////////////////////////////////////////////////////////////////////////// 835// attach existing thread 836 837// bootstrap the main thread 838bool os::create_main_thread(JavaThread* thread) { 839 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 840 return create_attached_thread(thread); 841} 842 843bool os::create_attached_thread(JavaThread* thread) { 844#ifdef ASSERT 845 thread->verify_not_published(); 846#endif 847 848 // Allocate the OSThread object 849 OSThread* osthread = new OSThread(NULL, NULL); 850 851 if (osthread == NULL) { 852 return false; 853 } 854 855 osthread->set_thread_id(os::Bsd::gettid()); 856 857 // Store pthread info into the OSThread 858#ifdef __APPLE__ 859 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 860 guarantee(unique_thread_id != 0, "just checking"); 861 osthread->set_unique_thread_id(unique_thread_id); 862#endif 863 osthread->set_pthread_id(::pthread_self()); 864 865 // initialize floating point control register 866 os::Bsd::init_thread_fpu_state(); 867 868 // Initial thread state is RUNNABLE 869 osthread->set_state(RUNNABLE); 870 871 thread->set_osthread(osthread); 872 873 // initialize signal mask for this thread 874 // and save the caller's signal mask 875 os::Bsd::hotspot_sigmask(thread); 876 877 return true; 878} 879 880void os::pd_start_thread(Thread* thread) { 881 OSThread * osthread = thread->osthread(); 882 assert(osthread->get_state() != INITIALIZED, "just checking"); 883 Monitor* sync_with_child = osthread->startThread_lock(); 884 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 885 sync_with_child->notify(); 886} 887 888// Free Bsd resources related to the OSThread 889void os::free_thread(OSThread* osthread) { 890 assert(osthread != NULL, "osthread not set"); 891 892 if (Thread::current()->osthread() == osthread) { 893 // Restore caller's signal mask 894 sigset_t sigmask = osthread->caller_sigmask(); 895 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 896 } 897 898 delete osthread; 899} 900 901////////////////////////////////////////////////////////////////////////////// 902// thread local storage 903 904// Restore the thread pointer if the destructor is called. This is in case 905// someone from JNI code sets up a destructor with pthread_key_create to run 906// detachCurrentThread on thread death. Unless we restore the thread pointer we 907// will hang or crash. When detachCurrentThread is called the key will be set 908// to null and we will not be called again. If detachCurrentThread is never 909// called we could loop forever depending on the pthread implementation. 910static void restore_thread_pointer(void* p) { 911 Thread* thread = (Thread*) p; 912 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread); 913} 914 915int os::allocate_thread_local_storage() { 916 pthread_key_t key; 917 int rslt = pthread_key_create(&key, restore_thread_pointer); 918 assert(rslt == 0, "cannot allocate thread local storage"); 919 return (int)key; 920} 921 922// Note: This is currently not used by VM, as we don't destroy TLS key 923// on VM exit. 924void os::free_thread_local_storage(int index) { 925 int rslt = pthread_key_delete((pthread_key_t)index); 926 assert(rslt == 0, "invalid index"); 927} 928 929void os::thread_local_storage_at_put(int index, void* value) { 930 int rslt = pthread_setspecific((pthread_key_t)index, value); 931 assert(rslt == 0, "pthread_setspecific failed"); 932} 933 934extern "C" Thread* get_thread() { 935 return ThreadLocalStorage::thread(); 936} 937 938 939//////////////////////////////////////////////////////////////////////////////// 940// time support 941 942// Time since start-up in seconds to a fine granularity. 943// Used by VMSelfDestructTimer and the MemProfiler. 944double os::elapsedTime() { 945 946 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 947} 948 949jlong os::elapsed_counter() { 950 return javaTimeNanos() - initial_time_count; 951} 952 953jlong os::elapsed_frequency() { 954 return NANOSECS_PER_SEC; // nanosecond resolution 955} 956 957bool os::supports_vtime() { return true; } 958bool os::enable_vtime() { return false; } 959bool os::vtime_enabled() { return false; } 960 961double os::elapsedVTime() { 962 // better than nothing, but not much 963 return elapsedTime(); 964} 965 966jlong os::javaTimeMillis() { 967 timeval time; 968 int status = gettimeofday(&time, NULL); 969 assert(status != -1, "bsd error"); 970 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 971} 972 973void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 974 timeval time; 975 int status = gettimeofday(&time, NULL); 976 assert(status != -1, "bsd error"); 977 seconds = jlong(time.tv_sec); 978 nanos = jlong(time.tv_usec) * 1000; 979} 980 981#ifndef __APPLE__ 982 #ifndef CLOCK_MONOTONIC 983 #define CLOCK_MONOTONIC (1) 984 #endif 985#endif 986 987#ifdef __APPLE__ 988void os::Bsd::clock_init() { 989 mach_timebase_info(&_timebase_info); 990} 991#else 992void os::Bsd::clock_init() { 993 struct timespec res; 994 struct timespec tp; 995 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 996 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 997 // yes, monotonic clock is supported 998 _clock_gettime = ::clock_gettime; 999 } 1000} 1001#endif 1002 1003 1004 1005#ifdef __APPLE__ 1006 1007jlong os::javaTimeNanos() { 1008 const uint64_t tm = mach_absolute_time(); 1009 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 1010 const uint64_t prev = Bsd::_max_abstime; 1011 if (now <= prev) { 1012 return prev; // same or retrograde time; 1013 } 1014 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 1015 assert(obsv >= prev, "invariant"); // Monotonicity 1016 // If the CAS succeeded then we're done and return "now". 1017 // If the CAS failed and the observed value "obsv" is >= now then 1018 // we should return "obsv". If the CAS failed and now > obsv > prv then 1019 // some other thread raced this thread and installed a new value, in which case 1020 // we could either (a) retry the entire operation, (b) retry trying to install now 1021 // or (c) just return obsv. We use (c). No loop is required although in some cases 1022 // we might discard a higher "now" value in deference to a slightly lower but freshly 1023 // installed obsv value. That's entirely benign -- it admits no new orderings compared 1024 // to (a) or (b) -- and greatly reduces coherence traffic. 1025 // We might also condition (c) on the magnitude of the delta between obsv and now. 1026 // Avoiding excessive CAS operations to hot RW locations is critical. 1027 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 1028 return (prev == obsv) ? now : obsv; 1029} 1030 1031#else // __APPLE__ 1032 1033jlong os::javaTimeNanos() { 1034 if (os::supports_monotonic_clock()) { 1035 struct timespec tp; 1036 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 1037 assert(status == 0, "gettime error"); 1038 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1039 return result; 1040 } else { 1041 timeval time; 1042 int status = gettimeofday(&time, NULL); 1043 assert(status != -1, "bsd error"); 1044 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1045 return 1000 * usecs; 1046 } 1047} 1048 1049#endif // __APPLE__ 1050 1051void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1052 if (os::supports_monotonic_clock()) { 1053 info_ptr->max_value = ALL_64_BITS; 1054 1055 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1056 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1057 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1058 } else { 1059 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1060 info_ptr->max_value = ALL_64_BITS; 1061 1062 // gettimeofday is a real time clock so it skips 1063 info_ptr->may_skip_backward = true; 1064 info_ptr->may_skip_forward = true; 1065 } 1066 1067 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1068} 1069 1070// Return the real, user, and system times in seconds from an 1071// arbitrary fixed point in the past. 1072bool os::getTimesSecs(double* process_real_time, 1073 double* process_user_time, 1074 double* process_system_time) { 1075 struct tms ticks; 1076 clock_t real_ticks = times(&ticks); 1077 1078 if (real_ticks == (clock_t) (-1)) { 1079 return false; 1080 } else { 1081 double ticks_per_second = (double) clock_tics_per_sec; 1082 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1083 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1084 *process_real_time = ((double) real_ticks) / ticks_per_second; 1085 1086 return true; 1087 } 1088} 1089 1090 1091char * os::local_time_string(char *buf, size_t buflen) { 1092 struct tm t; 1093 time_t long_time; 1094 time(&long_time); 1095 localtime_r(&long_time, &t); 1096 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1097 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1098 t.tm_hour, t.tm_min, t.tm_sec); 1099 return buf; 1100} 1101 1102struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1103 return localtime_r(clock, res); 1104} 1105 1106//////////////////////////////////////////////////////////////////////////////// 1107// runtime exit support 1108 1109// Note: os::shutdown() might be called very early during initialization, or 1110// called from signal handler. Before adding something to os::shutdown(), make 1111// sure it is async-safe and can handle partially initialized VM. 1112void os::shutdown() { 1113 1114 // allow PerfMemory to attempt cleanup of any persistent resources 1115 perfMemory_exit(); 1116 1117 // needs to remove object in file system 1118 AttachListener::abort(); 1119 1120 // flush buffered output, finish log files 1121 ostream_abort(); 1122 1123 // Check for abort hook 1124 abort_hook_t abort_hook = Arguments::abort_hook(); 1125 if (abort_hook != NULL) { 1126 abort_hook(); 1127 } 1128 1129} 1130 1131// Note: os::abort() might be called very early during initialization, or 1132// called from signal handler. Before adding something to os::abort(), make 1133// sure it is async-safe and can handle partially initialized VM. 1134void os::abort(bool dump_core) { 1135 abort(dump_core, NULL, NULL); 1136} 1137 1138void os::abort(bool dump_core, void* siginfo, void* context) { 1139 os::shutdown(); 1140 if (dump_core) { 1141#ifndef PRODUCT 1142 fdStream out(defaultStream::output_fd()); 1143 out.print_raw("Current thread is "); 1144 char buf[16]; 1145 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1146 out.print_raw_cr(buf); 1147 out.print_raw_cr("Dumping core ..."); 1148#endif 1149 ::abort(); // dump core 1150 } 1151 1152 ::exit(1); 1153} 1154 1155// Die immediately, no exit hook, no abort hook, no cleanup. 1156void os::die() { 1157 // _exit() on BsdThreads only kills current thread 1158 ::abort(); 1159} 1160 1161// This method is a copy of JDK's sysGetLastErrorString 1162// from src/solaris/hpi/src/system_md.c 1163 1164size_t os::lasterror(char *buf, size_t len) { 1165 if (errno == 0) return 0; 1166 1167 const char *s = ::strerror(errno); 1168 size_t n = ::strlen(s); 1169 if (n >= len) { 1170 n = len - 1; 1171 } 1172 ::strncpy(buf, s, n); 1173 buf[n] = '\0'; 1174 return n; 1175} 1176 1177// Information of current thread in variety of formats 1178pid_t os::Bsd::gettid() { 1179 int retval = -1; 1180 1181#ifdef __APPLE__ //XNU kernel 1182 // despite the fact mach port is actually not a thread id use it 1183 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1184 retval = ::pthread_mach_thread_np(::pthread_self()); 1185 guarantee(retval != 0, "just checking"); 1186 return retval; 1187 1188#elif __FreeBSD__ 1189 retval = syscall(SYS_thr_self); 1190#elif __OpenBSD__ 1191 retval = syscall(SYS_getthrid); 1192#elif __NetBSD__ 1193 retval = (pid_t) syscall(SYS__lwp_self); 1194#endif 1195 1196 if (retval == -1) { 1197 return getpid(); 1198 } 1199} 1200 1201intx os::current_thread_id() { 1202#ifdef __APPLE__ 1203 return (intx)::pthread_mach_thread_np(::pthread_self()); 1204#else 1205 return (intx)::pthread_self(); 1206#endif 1207} 1208 1209int os::current_process_id() { 1210 1211 // Under the old bsd thread library, bsd gives each thread 1212 // its own process id. Because of this each thread will return 1213 // a different pid if this method were to return the result 1214 // of getpid(2). Bsd provides no api that returns the pid 1215 // of the launcher thread for the vm. This implementation 1216 // returns a unique pid, the pid of the launcher thread 1217 // that starts the vm 'process'. 1218 1219 // Under the NPTL, getpid() returns the same pid as the 1220 // launcher thread rather than a unique pid per thread. 1221 // Use gettid() if you want the old pre NPTL behaviour. 1222 1223 // if you are looking for the result of a call to getpid() that 1224 // returns a unique pid for the calling thread, then look at the 1225 // OSThread::thread_id() method in osThread_bsd.hpp file 1226 1227 return (int)(_initial_pid ? _initial_pid : getpid()); 1228} 1229 1230// DLL functions 1231 1232#define JNI_LIB_PREFIX "lib" 1233#ifdef __APPLE__ 1234 #define JNI_LIB_SUFFIX ".dylib" 1235#else 1236 #define JNI_LIB_SUFFIX ".so" 1237#endif 1238 1239const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1240 1241// This must be hard coded because it's the system's temporary 1242// directory not the java application's temp directory, ala java.io.tmpdir. 1243#ifdef __APPLE__ 1244// macosx has a secure per-user temporary directory 1245char temp_path_storage[PATH_MAX]; 1246const char* os::get_temp_directory() { 1247 static char *temp_path = NULL; 1248 if (temp_path == NULL) { 1249 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1250 if (pathSize == 0 || pathSize > PATH_MAX) { 1251 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1252 } 1253 temp_path = temp_path_storage; 1254 } 1255 return temp_path; 1256} 1257#else // __APPLE__ 1258const char* os::get_temp_directory() { return "/tmp"; } 1259#endif // __APPLE__ 1260 1261static bool file_exists(const char* filename) { 1262 struct stat statbuf; 1263 if (filename == NULL || strlen(filename) == 0) { 1264 return false; 1265 } 1266 return os::stat(filename, &statbuf) == 0; 1267} 1268 1269bool os::dll_build_name(char* buffer, size_t buflen, 1270 const char* pname, const char* fname) { 1271 bool retval = false; 1272 // Copied from libhpi 1273 const size_t pnamelen = pname ? strlen(pname) : 0; 1274 1275 // Return error on buffer overflow. 1276 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1277 return retval; 1278 } 1279 1280 if (pnamelen == 0) { 1281 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1282 retval = true; 1283 } else if (strchr(pname, *os::path_separator()) != NULL) { 1284 int n; 1285 char** pelements = split_path(pname, &n); 1286 if (pelements == NULL) { 1287 return false; 1288 } 1289 for (int i = 0; i < n; i++) { 1290 // Really shouldn't be NULL, but check can't hurt 1291 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1292 continue; // skip the empty path values 1293 } 1294 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1295 pelements[i], fname); 1296 if (file_exists(buffer)) { 1297 retval = true; 1298 break; 1299 } 1300 } 1301 // release the storage 1302 for (int i = 0; i < n; i++) { 1303 if (pelements[i] != NULL) { 1304 FREE_C_HEAP_ARRAY(char, pelements[i]); 1305 } 1306 } 1307 if (pelements != NULL) { 1308 FREE_C_HEAP_ARRAY(char*, pelements); 1309 } 1310 } else { 1311 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1312 retval = true; 1313 } 1314 return retval; 1315} 1316 1317// check if addr is inside libjvm.so 1318bool os::address_is_in_vm(address addr) { 1319 static address libjvm_base_addr; 1320 Dl_info dlinfo; 1321 1322 if (libjvm_base_addr == NULL) { 1323 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1324 libjvm_base_addr = (address)dlinfo.dli_fbase; 1325 } 1326 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1327 } 1328 1329 if (dladdr((void *)addr, &dlinfo) != 0) { 1330 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1331 } 1332 1333 return false; 1334} 1335 1336 1337#define MACH_MAXSYMLEN 256 1338 1339bool os::dll_address_to_function_name(address addr, char *buf, 1340 int buflen, int *offset) { 1341 // buf is not optional, but offset is optional 1342 assert(buf != NULL, "sanity check"); 1343 1344 Dl_info dlinfo; 1345 char localbuf[MACH_MAXSYMLEN]; 1346 1347 if (dladdr((void*)addr, &dlinfo) != 0) { 1348 // see if we have a matching symbol 1349 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1350 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1351 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1352 } 1353 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1354 return true; 1355 } 1356 // no matching symbol so try for just file info 1357 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1358 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1359 buf, buflen, offset, dlinfo.dli_fname)) { 1360 return true; 1361 } 1362 } 1363 1364 // Handle non-dynamic manually: 1365 if (dlinfo.dli_fbase != NULL && 1366 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) { 1367 if (!Decoder::demangle(localbuf, buf, buflen)) { 1368 jio_snprintf(buf, buflen, "%s", localbuf); 1369 } 1370 return true; 1371 } 1372 } 1373 buf[0] = '\0'; 1374 if (offset != NULL) *offset = -1; 1375 return false; 1376} 1377 1378// ported from solaris version 1379bool os::dll_address_to_library_name(address addr, char* buf, 1380 int buflen, int* offset) { 1381 // buf is not optional, but offset is optional 1382 assert(buf != NULL, "sanity check"); 1383 1384 Dl_info dlinfo; 1385 1386 if (dladdr((void*)addr, &dlinfo) != 0) { 1387 if (dlinfo.dli_fname != NULL) { 1388 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1389 } 1390 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1391 *offset = addr - (address)dlinfo.dli_fbase; 1392 } 1393 return true; 1394 } 1395 1396 buf[0] = '\0'; 1397 if (offset) *offset = -1; 1398 return false; 1399} 1400 1401// Loads .dll/.so and 1402// in case of error it checks if .dll/.so was built for the 1403// same architecture as Hotspot is running on 1404 1405#ifdef __APPLE__ 1406void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1407 void * result= ::dlopen(filename, RTLD_LAZY); 1408 if (result != NULL) { 1409 // Successful loading 1410 return result; 1411 } 1412 1413 // Read system error message into ebuf 1414 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1415 ebuf[ebuflen-1]='\0'; 1416 1417 return NULL; 1418} 1419#else 1420void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1421 void * result= ::dlopen(filename, RTLD_LAZY); 1422 if (result != NULL) { 1423 // Successful loading 1424 return result; 1425 } 1426 1427 Elf32_Ehdr elf_head; 1428 1429 // Read system error message into ebuf 1430 // It may or may not be overwritten below 1431 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1432 ebuf[ebuflen-1]='\0'; 1433 int diag_msg_max_length=ebuflen-strlen(ebuf); 1434 char* diag_msg_buf=ebuf+strlen(ebuf); 1435 1436 if (diag_msg_max_length==0) { 1437 // No more space in ebuf for additional diagnostics message 1438 return NULL; 1439 } 1440 1441 1442 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1443 1444 if (file_descriptor < 0) { 1445 // Can't open library, report dlerror() message 1446 return NULL; 1447 } 1448 1449 bool failed_to_read_elf_head= 1450 (sizeof(elf_head)!= 1451 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1452 1453 ::close(file_descriptor); 1454 if (failed_to_read_elf_head) { 1455 // file i/o error - report dlerror() msg 1456 return NULL; 1457 } 1458 1459 typedef struct { 1460 Elf32_Half code; // Actual value as defined in elf.h 1461 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1462 char elf_class; // 32 or 64 bit 1463 char endianess; // MSB or LSB 1464 char* name; // String representation 1465 } arch_t; 1466 1467 #ifndef EM_486 1468 #define EM_486 6 /* Intel 80486 */ 1469 #endif 1470 1471 #ifndef EM_MIPS_RS3_LE 1472 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1473 #endif 1474 1475 #ifndef EM_PPC64 1476 #define EM_PPC64 21 /* PowerPC64 */ 1477 #endif 1478 1479 #ifndef EM_S390 1480 #define EM_S390 22 /* IBM System/390 */ 1481 #endif 1482 1483 #ifndef EM_IA_64 1484 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1485 #endif 1486 1487 #ifndef EM_X86_64 1488 #define EM_X86_64 62 /* AMD x86-64 */ 1489 #endif 1490 1491 static const arch_t arch_array[]={ 1492 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1493 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1494 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1495 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1496 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1497 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1498 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1499 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1500 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1501 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1502 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1503 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1504 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1505 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1506 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1507 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1508 }; 1509 1510 #if (defined IA32) 1511 static Elf32_Half running_arch_code=EM_386; 1512 #elif (defined AMD64) 1513 static Elf32_Half running_arch_code=EM_X86_64; 1514 #elif (defined IA64) 1515 static Elf32_Half running_arch_code=EM_IA_64; 1516 #elif (defined __sparc) && (defined _LP64) 1517 static Elf32_Half running_arch_code=EM_SPARCV9; 1518 #elif (defined __sparc) && (!defined _LP64) 1519 static Elf32_Half running_arch_code=EM_SPARC; 1520 #elif (defined __powerpc64__) 1521 static Elf32_Half running_arch_code=EM_PPC64; 1522 #elif (defined __powerpc__) 1523 static Elf32_Half running_arch_code=EM_PPC; 1524 #elif (defined ARM) 1525 static Elf32_Half running_arch_code=EM_ARM; 1526 #elif (defined S390) 1527 static Elf32_Half running_arch_code=EM_S390; 1528 #elif (defined ALPHA) 1529 static Elf32_Half running_arch_code=EM_ALPHA; 1530 #elif (defined MIPSEL) 1531 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1532 #elif (defined PARISC) 1533 static Elf32_Half running_arch_code=EM_PARISC; 1534 #elif (defined MIPS) 1535 static Elf32_Half running_arch_code=EM_MIPS; 1536 #elif (defined M68K) 1537 static Elf32_Half running_arch_code=EM_68K; 1538 #else 1539 #error Method os::dll_load requires that one of following is defined:\ 1540 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1541 #endif 1542 1543 // Identify compatability class for VM's architecture and library's architecture 1544 // Obtain string descriptions for architectures 1545 1546 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1547 int running_arch_index=-1; 1548 1549 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1550 if (running_arch_code == arch_array[i].code) { 1551 running_arch_index = i; 1552 } 1553 if (lib_arch.code == arch_array[i].code) { 1554 lib_arch.compat_class = arch_array[i].compat_class; 1555 lib_arch.name = arch_array[i].name; 1556 } 1557 } 1558 1559 assert(running_arch_index != -1, 1560 "Didn't find running architecture code (running_arch_code) in arch_array"); 1561 if (running_arch_index == -1) { 1562 // Even though running architecture detection failed 1563 // we may still continue with reporting dlerror() message 1564 return NULL; 1565 } 1566 1567 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1568 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1569 return NULL; 1570 } 1571 1572#ifndef S390 1573 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1574 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1575 return NULL; 1576 } 1577#endif // !S390 1578 1579 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1580 if (lib_arch.name!=NULL) { 1581 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1582 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1583 lib_arch.name, arch_array[running_arch_index].name); 1584 } else { 1585 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1586 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1587 lib_arch.code, 1588 arch_array[running_arch_index].name); 1589 } 1590 } 1591 1592 return NULL; 1593} 1594#endif // !__APPLE__ 1595 1596void* os::get_default_process_handle() { 1597#ifdef __APPLE__ 1598 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1599 // to avoid finding unexpected symbols on second (or later) 1600 // loads of a library. 1601 return (void*)::dlopen(NULL, RTLD_FIRST); 1602#else 1603 return (void*)::dlopen(NULL, RTLD_LAZY); 1604#endif 1605} 1606 1607// XXX: Do we need a lock around this as per Linux? 1608void* os::dll_lookup(void* handle, const char* name) { 1609 return dlsym(handle, name); 1610} 1611 1612 1613static bool _print_ascii_file(const char* filename, outputStream* st) { 1614 int fd = ::open(filename, O_RDONLY); 1615 if (fd == -1) { 1616 return false; 1617 } 1618 1619 char buf[32]; 1620 int bytes; 1621 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1622 st->print_raw(buf, bytes); 1623 } 1624 1625 ::close(fd); 1626 1627 return true; 1628} 1629 1630int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1631 outputStream * out = (outputStream *) param; 1632 out->print_cr(PTR_FORMAT " \t%s", base_address, name); 1633 return 0; 1634} 1635 1636void os::print_dll_info(outputStream *st) { 1637 st->print_cr("Dynamic libraries:"); 1638 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1639 st->print_cr("Error: Cannot print dynamic libraries."); 1640 } 1641} 1642 1643int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1644#ifdef RTLD_DI_LINKMAP 1645 Dl_info dli; 1646 void *handle; 1647 Link_map *map; 1648 Link_map *p; 1649 1650 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1651 dli.dli_fname == NULL) { 1652 return 1; 1653 } 1654 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1655 if (handle == NULL) { 1656 return 1; 1657 } 1658 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1659 if (map == NULL) { 1660 dlclose(handle); 1661 return 1; 1662 } 1663 1664 while (map->l_prev != NULL) 1665 map = map->l_prev; 1666 1667 while (map != NULL) { 1668 // Value for top_address is returned as 0 since we don't have any information about module size 1669 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1670 dlclose(handle); 1671 return 1; 1672 } 1673 map = map->l_next; 1674 } 1675 1676 dlclose(handle); 1677#elif defined(__APPLE__) 1678 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1679 // Value for top_address is returned as 0 since we don't have any information about module size 1680 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1681 return 1; 1682 } 1683 } 1684 return 0; 1685#else 1686 return 1; 1687#endif 1688} 1689 1690void os::print_os_info_brief(outputStream* st) { 1691 st->print("Bsd"); 1692 1693 os::Posix::print_uname_info(st); 1694} 1695 1696void os::print_os_info(outputStream* st) { 1697 st->print("OS:"); 1698 st->print("Bsd"); 1699 1700 os::Posix::print_uname_info(st); 1701 1702 os::Posix::print_rlimit_info(st); 1703 1704 os::Posix::print_load_average(st); 1705} 1706 1707void os::pd_print_cpu_info(outputStream* st) { 1708 // Nothing to do for now. 1709} 1710 1711void os::print_memory_info(outputStream* st) { 1712 1713 st->print("Memory:"); 1714 st->print(" %dk page", os::vm_page_size()>>10); 1715 1716 st->print(", physical " UINT64_FORMAT "k", 1717 os::physical_memory() >> 10); 1718 st->print("(" UINT64_FORMAT "k free)", 1719 os::available_memory() >> 10); 1720 st->cr(); 1721 1722 // meminfo 1723 st->print("\n/proc/meminfo:\n"); 1724 _print_ascii_file("/proc/meminfo", st); 1725 st->cr(); 1726} 1727 1728void os::print_siginfo(outputStream* st, void* siginfo) { 1729 const siginfo_t* si = (const siginfo_t*)siginfo; 1730 1731 os::Posix::print_siginfo_brief(st, si); 1732 1733 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1734 UseSharedSpaces) { 1735 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1736 if (mapinfo->is_in_shared_space(si->si_addr)) { 1737 st->print("\n\nError accessing class data sharing archive." \ 1738 " Mapped file inaccessible during execution, " \ 1739 " possible disk/network problem."); 1740 } 1741 } 1742 st->cr(); 1743} 1744 1745 1746static void print_signal_handler(outputStream* st, int sig, 1747 char* buf, size_t buflen); 1748 1749void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1750 st->print_cr("Signal Handlers:"); 1751 print_signal_handler(st, SIGSEGV, buf, buflen); 1752 print_signal_handler(st, SIGBUS , buf, buflen); 1753 print_signal_handler(st, SIGFPE , buf, buflen); 1754 print_signal_handler(st, SIGPIPE, buf, buflen); 1755 print_signal_handler(st, SIGXFSZ, buf, buflen); 1756 print_signal_handler(st, SIGILL , buf, buflen); 1757 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1758 print_signal_handler(st, SR_signum, buf, buflen); 1759 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1760 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1761 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1762 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1763} 1764 1765static char saved_jvm_path[MAXPATHLEN] = {0}; 1766 1767// Find the full path to the current module, libjvm 1768void os::jvm_path(char *buf, jint buflen) { 1769 // Error checking. 1770 if (buflen < MAXPATHLEN) { 1771 assert(false, "must use a large-enough buffer"); 1772 buf[0] = '\0'; 1773 return; 1774 } 1775 // Lazy resolve the path to current module. 1776 if (saved_jvm_path[0] != 0) { 1777 strcpy(buf, saved_jvm_path); 1778 return; 1779 } 1780 1781 char dli_fname[MAXPATHLEN]; 1782 bool ret = dll_address_to_library_name( 1783 CAST_FROM_FN_PTR(address, os::jvm_path), 1784 dli_fname, sizeof(dli_fname), NULL); 1785 assert(ret, "cannot locate libjvm"); 1786 char *rp = NULL; 1787 if (ret && dli_fname[0] != '\0') { 1788 rp = realpath(dli_fname, buf); 1789 } 1790 if (rp == NULL) { 1791 return; 1792 } 1793 1794 if (Arguments::sun_java_launcher_is_altjvm()) { 1795 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1796 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1797 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1798 // appears at the right place in the string, then assume we are 1799 // installed in a JDK and we're done. Otherwise, check for a 1800 // JAVA_HOME environment variable and construct a path to the JVM 1801 // being overridden. 1802 1803 const char *p = buf + strlen(buf) - 1; 1804 for (int count = 0; p > buf && count < 5; ++count) { 1805 for (--p; p > buf && *p != '/'; --p) 1806 /* empty */ ; 1807 } 1808 1809 if (strncmp(p, "/jre/lib/", 9) != 0) { 1810 // Look for JAVA_HOME in the environment. 1811 char* java_home_var = ::getenv("JAVA_HOME"); 1812 if (java_home_var != NULL && java_home_var[0] != 0) { 1813 char* jrelib_p; 1814 int len; 1815 1816 // Check the current module name "libjvm" 1817 p = strrchr(buf, '/'); 1818 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1819 1820 rp = realpath(java_home_var, buf); 1821 if (rp == NULL) { 1822 return; 1823 } 1824 1825 // determine if this is a legacy image or modules image 1826 // modules image doesn't have "jre" subdirectory 1827 len = strlen(buf); 1828 assert(len < buflen, "Ran out of buffer space"); 1829 jrelib_p = buf + len; 1830 1831 // Add the appropriate library subdir 1832 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1833 if (0 != access(buf, F_OK)) { 1834 snprintf(jrelib_p, buflen-len, "/lib"); 1835 } 1836 1837 // Add the appropriate client or server subdir 1838 len = strlen(buf); 1839 jrelib_p = buf + len; 1840 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1841 if (0 != access(buf, F_OK)) { 1842 snprintf(jrelib_p, buflen-len, "%s", ""); 1843 } 1844 1845 // If the path exists within JAVA_HOME, add the JVM library name 1846 // to complete the path to JVM being overridden. Otherwise fallback 1847 // to the path to the current library. 1848 if (0 == access(buf, F_OK)) { 1849 // Use current module name "libjvm" 1850 len = strlen(buf); 1851 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1852 } else { 1853 // Fall back to path of current library 1854 rp = realpath(dli_fname, buf); 1855 if (rp == NULL) { 1856 return; 1857 } 1858 } 1859 } 1860 } 1861 } 1862 1863 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1864 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1865} 1866 1867void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1868 // no prefix required, not even "_" 1869} 1870 1871void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1872 // no suffix required 1873} 1874 1875//////////////////////////////////////////////////////////////////////////////// 1876// sun.misc.Signal support 1877 1878static volatile jint sigint_count = 0; 1879 1880static void UserHandler(int sig, void *siginfo, void *context) { 1881 // 4511530 - sem_post is serialized and handled by the manager thread. When 1882 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1883 // don't want to flood the manager thread with sem_post requests. 1884 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1885 return; 1886 } 1887 1888 // Ctrl-C is pressed during error reporting, likely because the error 1889 // handler fails to abort. Let VM die immediately. 1890 if (sig == SIGINT && is_error_reported()) { 1891 os::die(); 1892 } 1893 1894 os::signal_notify(sig); 1895} 1896 1897void* os::user_handler() { 1898 return CAST_FROM_FN_PTR(void*, UserHandler); 1899} 1900 1901extern "C" { 1902 typedef void (*sa_handler_t)(int); 1903 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1904} 1905 1906void* os::signal(int signal_number, void* handler) { 1907 struct sigaction sigAct, oldSigAct; 1908 1909 sigfillset(&(sigAct.sa_mask)); 1910 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1911 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1912 1913 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1914 // -1 means registration failed 1915 return (void *)-1; 1916 } 1917 1918 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1919} 1920 1921void os::signal_raise(int signal_number) { 1922 ::raise(signal_number); 1923} 1924 1925// The following code is moved from os.cpp for making this 1926// code platform specific, which it is by its very nature. 1927 1928// Will be modified when max signal is changed to be dynamic 1929int os::sigexitnum_pd() { 1930 return NSIG; 1931} 1932 1933// a counter for each possible signal value 1934static volatile jint pending_signals[NSIG+1] = { 0 }; 1935 1936// Bsd(POSIX) specific hand shaking semaphore. 1937#ifdef __APPLE__ 1938typedef semaphore_t os_semaphore_t; 1939 1940 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1941 #define SEM_WAIT(sem) semaphore_wait(sem) 1942 #define SEM_POST(sem) semaphore_signal(sem) 1943 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1944#else 1945typedef sem_t os_semaphore_t; 1946 1947 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1948 #define SEM_WAIT(sem) sem_wait(&sem) 1949 #define SEM_POST(sem) sem_post(&sem) 1950 #define SEM_DESTROY(sem) sem_destroy(&sem) 1951#endif 1952 1953class Semaphore : public StackObj { 1954 public: 1955 Semaphore(); 1956 ~Semaphore(); 1957 void signal(); 1958 void wait(); 1959 bool trywait(); 1960 bool timedwait(unsigned int sec, int nsec); 1961 private: 1962 jlong currenttime() const; 1963 os_semaphore_t _semaphore; 1964}; 1965 1966Semaphore::Semaphore() : _semaphore(0) { 1967 SEM_INIT(_semaphore, 0); 1968} 1969 1970Semaphore::~Semaphore() { 1971 SEM_DESTROY(_semaphore); 1972} 1973 1974void Semaphore::signal() { 1975 SEM_POST(_semaphore); 1976} 1977 1978void Semaphore::wait() { 1979 SEM_WAIT(_semaphore); 1980} 1981 1982jlong Semaphore::currenttime() const { 1983 struct timeval tv; 1984 gettimeofday(&tv, NULL); 1985 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1986} 1987 1988#ifdef __APPLE__ 1989bool Semaphore::trywait() { 1990 return timedwait(0, 0); 1991} 1992 1993bool Semaphore::timedwait(unsigned int sec, int nsec) { 1994 kern_return_t kr = KERN_ABORTED; 1995 mach_timespec_t waitspec; 1996 waitspec.tv_sec = sec; 1997 waitspec.tv_nsec = nsec; 1998 1999 jlong starttime = currenttime(); 2000 2001 kr = semaphore_timedwait(_semaphore, waitspec); 2002 while (kr == KERN_ABORTED) { 2003 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 2004 2005 jlong current = currenttime(); 2006 jlong passedtime = current - starttime; 2007 2008 if (passedtime >= totalwait) { 2009 waitspec.tv_sec = 0; 2010 waitspec.tv_nsec = 0; 2011 } else { 2012 jlong waittime = totalwait - (current - starttime); 2013 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2014 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2015 } 2016 2017 kr = semaphore_timedwait(_semaphore, waitspec); 2018 } 2019 2020 return kr == KERN_SUCCESS; 2021} 2022 2023#else 2024 2025bool Semaphore::trywait() { 2026 return sem_trywait(&_semaphore) == 0; 2027} 2028 2029bool Semaphore::timedwait(unsigned int sec, int nsec) { 2030 struct timespec ts; 2031 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2032 2033 while (1) { 2034 int result = sem_timedwait(&_semaphore, &ts); 2035 if (result == 0) { 2036 return true; 2037 } else if (errno == EINTR) { 2038 continue; 2039 } else if (errno == ETIMEDOUT) { 2040 return false; 2041 } else { 2042 return false; 2043 } 2044 } 2045} 2046 2047#endif // __APPLE__ 2048 2049static os_semaphore_t sig_sem; 2050static Semaphore sr_semaphore; 2051 2052void os::signal_init_pd() { 2053 // Initialize signal structures 2054 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2055 2056 // Initialize signal semaphore 2057 ::SEM_INIT(sig_sem, 0); 2058} 2059 2060void os::signal_notify(int sig) { 2061 Atomic::inc(&pending_signals[sig]); 2062 ::SEM_POST(sig_sem); 2063} 2064 2065static int check_pending_signals(bool wait) { 2066 Atomic::store(0, &sigint_count); 2067 for (;;) { 2068 for (int i = 0; i < NSIG + 1; i++) { 2069 jint n = pending_signals[i]; 2070 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2071 return i; 2072 } 2073 } 2074 if (!wait) { 2075 return -1; 2076 } 2077 JavaThread *thread = JavaThread::current(); 2078 ThreadBlockInVM tbivm(thread); 2079 2080 bool threadIsSuspended; 2081 do { 2082 thread->set_suspend_equivalent(); 2083 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2084 ::SEM_WAIT(sig_sem); 2085 2086 // were we externally suspended while we were waiting? 2087 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2088 if (threadIsSuspended) { 2089 // The semaphore has been incremented, but while we were waiting 2090 // another thread suspended us. We don't want to continue running 2091 // while suspended because that would surprise the thread that 2092 // suspended us. 2093 ::SEM_POST(sig_sem); 2094 2095 thread->java_suspend_self(); 2096 } 2097 } while (threadIsSuspended); 2098 } 2099} 2100 2101int os::signal_lookup() { 2102 return check_pending_signals(false); 2103} 2104 2105int os::signal_wait() { 2106 return check_pending_signals(true); 2107} 2108 2109//////////////////////////////////////////////////////////////////////////////// 2110// Virtual Memory 2111 2112int os::vm_page_size() { 2113 // Seems redundant as all get out 2114 assert(os::Bsd::page_size() != -1, "must call os::init"); 2115 return os::Bsd::page_size(); 2116} 2117 2118// Solaris allocates memory by pages. 2119int os::vm_allocation_granularity() { 2120 assert(os::Bsd::page_size() != -1, "must call os::init"); 2121 return os::Bsd::page_size(); 2122} 2123 2124// Rationale behind this function: 2125// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2126// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2127// samples for JITted code. Here we create private executable mapping over the code cache 2128// and then we can use standard (well, almost, as mapping can change) way to provide 2129// info for the reporting script by storing timestamp and location of symbol 2130void bsd_wrap_code(char* base, size_t size) { 2131 static volatile jint cnt = 0; 2132 2133 if (!UseOprofile) { 2134 return; 2135 } 2136 2137 char buf[PATH_MAX + 1]; 2138 int num = Atomic::add(1, &cnt); 2139 2140 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2141 os::get_temp_directory(), os::current_process_id(), num); 2142 unlink(buf); 2143 2144 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2145 2146 if (fd != -1) { 2147 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2148 if (rv != (off_t)-1) { 2149 if (::write(fd, "", 1) == 1) { 2150 mmap(base, size, 2151 PROT_READ|PROT_WRITE|PROT_EXEC, 2152 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2153 } 2154 } 2155 ::close(fd); 2156 unlink(buf); 2157 } 2158} 2159 2160static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2161 int err) { 2162 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2163 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2164 strerror(err), err); 2165} 2166 2167// NOTE: Bsd kernel does not really reserve the pages for us. 2168// All it does is to check if there are enough free pages 2169// left at the time of mmap(). This could be a potential 2170// problem. 2171bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2172 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2173#ifdef __OpenBSD__ 2174 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2175 if (::mprotect(addr, size, prot) == 0) { 2176 return true; 2177 } 2178#else 2179 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2180 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2181 if (res != (uintptr_t) MAP_FAILED) { 2182 return true; 2183 } 2184#endif 2185 2186 // Warn about any commit errors we see in non-product builds just 2187 // in case mmap() doesn't work as described on the man page. 2188 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2189 2190 return false; 2191} 2192 2193bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2194 bool exec) { 2195 // alignment_hint is ignored on this OS 2196 return pd_commit_memory(addr, size, exec); 2197} 2198 2199void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2200 const char* mesg) { 2201 assert(mesg != NULL, "mesg must be specified"); 2202 if (!pd_commit_memory(addr, size, exec)) { 2203 // add extra info in product mode for vm_exit_out_of_memory(): 2204 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2205 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2206 } 2207} 2208 2209void os::pd_commit_memory_or_exit(char* addr, size_t size, 2210 size_t alignment_hint, bool exec, 2211 const char* mesg) { 2212 // alignment_hint is ignored on this OS 2213 pd_commit_memory_or_exit(addr, size, exec, mesg); 2214} 2215 2216void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2217} 2218 2219void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2220 ::madvise(addr, bytes, MADV_DONTNEED); 2221} 2222 2223void os::numa_make_global(char *addr, size_t bytes) { 2224} 2225 2226void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2227} 2228 2229bool os::numa_topology_changed() { return false; } 2230 2231size_t os::numa_get_groups_num() { 2232 return 1; 2233} 2234 2235int os::numa_get_group_id() { 2236 return 0; 2237} 2238 2239size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2240 if (size > 0) { 2241 ids[0] = 0; 2242 return 1; 2243 } 2244 return 0; 2245} 2246 2247bool os::get_page_info(char *start, page_info* info) { 2248 return false; 2249} 2250 2251char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2252 return end; 2253} 2254 2255 2256bool os::pd_uncommit_memory(char* addr, size_t size) { 2257#ifdef __OpenBSD__ 2258 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2259 return ::mprotect(addr, size, PROT_NONE) == 0; 2260#else 2261 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2262 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2263 return res != (uintptr_t) MAP_FAILED; 2264#endif 2265} 2266 2267bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2268 return os::commit_memory(addr, size, !ExecMem); 2269} 2270 2271// If this is a growable mapping, remove the guard pages entirely by 2272// munmap()ping them. If not, just call uncommit_memory(). 2273bool os::remove_stack_guard_pages(char* addr, size_t size) { 2274 return os::uncommit_memory(addr, size); 2275} 2276 2277static address _highest_vm_reserved_address = NULL; 2278 2279// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2280// at 'requested_addr'. If there are existing memory mappings at the same 2281// location, however, they will be overwritten. If 'fixed' is false, 2282// 'requested_addr' is only treated as a hint, the return value may or 2283// may not start from the requested address. Unlike Bsd mmap(), this 2284// function returns NULL to indicate failure. 2285static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2286 char * addr; 2287 int flags; 2288 2289 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2290 if (fixed) { 2291 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2292 flags |= MAP_FIXED; 2293 } 2294 2295 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2296 // touch an uncommitted page. Otherwise, the read/write might 2297 // succeed if we have enough swap space to back the physical page. 2298 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2299 flags, -1, 0); 2300 2301 if (addr != MAP_FAILED) { 2302 // anon_mmap() should only get called during VM initialization, 2303 // don't need lock (actually we can skip locking even it can be called 2304 // from multiple threads, because _highest_vm_reserved_address is just a 2305 // hint about the upper limit of non-stack memory regions.) 2306 if ((address)addr + bytes > _highest_vm_reserved_address) { 2307 _highest_vm_reserved_address = (address)addr + bytes; 2308 } 2309 } 2310 2311 return addr == MAP_FAILED ? NULL : addr; 2312} 2313 2314// Don't update _highest_vm_reserved_address, because there might be memory 2315// regions above addr + size. If so, releasing a memory region only creates 2316// a hole in the address space, it doesn't help prevent heap-stack collision. 2317// 2318static int anon_munmap(char * addr, size_t size) { 2319 return ::munmap(addr, size) == 0; 2320} 2321 2322char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2323 size_t alignment_hint) { 2324 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2325} 2326 2327bool os::pd_release_memory(char* addr, size_t size) { 2328 return anon_munmap(addr, size); 2329} 2330 2331static bool bsd_mprotect(char* addr, size_t size, int prot) { 2332 // Bsd wants the mprotect address argument to be page aligned. 2333 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2334 2335 // According to SUSv3, mprotect() should only be used with mappings 2336 // established by mmap(), and mmap() always maps whole pages. Unaligned 2337 // 'addr' likely indicates problem in the VM (e.g. trying to change 2338 // protection of malloc'ed or statically allocated memory). Check the 2339 // caller if you hit this assert. 2340 assert(addr == bottom, "sanity check"); 2341 2342 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2343 return ::mprotect(bottom, size, prot) == 0; 2344} 2345 2346// Set protections specified 2347bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2348 bool is_committed) { 2349 unsigned int p = 0; 2350 switch (prot) { 2351 case MEM_PROT_NONE: p = PROT_NONE; break; 2352 case MEM_PROT_READ: p = PROT_READ; break; 2353 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2354 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2355 default: 2356 ShouldNotReachHere(); 2357 } 2358 // is_committed is unused. 2359 return bsd_mprotect(addr, bytes, p); 2360} 2361 2362bool os::guard_memory(char* addr, size_t size) { 2363 return bsd_mprotect(addr, size, PROT_NONE); 2364} 2365 2366bool os::unguard_memory(char* addr, size_t size) { 2367 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2368} 2369 2370bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2371 return false; 2372} 2373 2374// Large page support 2375 2376static size_t _large_page_size = 0; 2377 2378void os::large_page_init() { 2379} 2380 2381 2382char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2383 fatal("This code is not used or maintained."); 2384 2385 // "exec" is passed in but not used. Creating the shared image for 2386 // the code cache doesn't have an SHM_X executable permission to check. 2387 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2388 2389 key_t key = IPC_PRIVATE; 2390 char *addr; 2391 2392 bool warn_on_failure = UseLargePages && 2393 (!FLAG_IS_DEFAULT(UseLargePages) || 2394 !FLAG_IS_DEFAULT(LargePageSizeInBytes)); 2395 2396 // Create a large shared memory region to attach to based on size. 2397 // Currently, size is the total size of the heap 2398 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2399 if (shmid == -1) { 2400 // Possible reasons for shmget failure: 2401 // 1. shmmax is too small for Java heap. 2402 // > check shmmax value: cat /proc/sys/kernel/shmmax 2403 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2404 // 2. not enough large page memory. 2405 // > check available large pages: cat /proc/meminfo 2406 // > increase amount of large pages: 2407 // echo new_value > /proc/sys/vm/nr_hugepages 2408 // Note 1: different Bsd may use different name for this property, 2409 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2410 // Note 2: it's possible there's enough physical memory available but 2411 // they are so fragmented after a long run that they can't 2412 // coalesce into large pages. Try to reserve large pages when 2413 // the system is still "fresh". 2414 if (warn_on_failure) { 2415 warning("Failed to reserve shared memory (errno = %d).", errno); 2416 } 2417 return NULL; 2418 } 2419 2420 // attach to the region 2421 addr = (char*)shmat(shmid, req_addr, 0); 2422 int err = errno; 2423 2424 // Remove shmid. If shmat() is successful, the actual shared memory segment 2425 // will be deleted when it's detached by shmdt() or when the process 2426 // terminates. If shmat() is not successful this will remove the shared 2427 // segment immediately. 2428 shmctl(shmid, IPC_RMID, NULL); 2429 2430 if ((intptr_t)addr == -1) { 2431 if (warn_on_failure) { 2432 warning("Failed to attach shared memory (errno = %d).", err); 2433 } 2434 return NULL; 2435 } 2436 2437 // The memory is committed 2438 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2439 2440 return addr; 2441} 2442 2443bool os::release_memory_special(char* base, size_t bytes) { 2444 if (MemTracker::tracking_level() > NMT_minimal) { 2445 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2446 // detaching the SHM segment will also delete it, see reserve_memory_special() 2447 int rslt = shmdt(base); 2448 if (rslt == 0) { 2449 tkr.record((address)base, bytes); 2450 return true; 2451 } else { 2452 return false; 2453 } 2454 } else { 2455 return shmdt(base) == 0; 2456 } 2457} 2458 2459size_t os::large_page_size() { 2460 return _large_page_size; 2461} 2462 2463// HugeTLBFS allows application to commit large page memory on demand; 2464// with SysV SHM the entire memory region must be allocated as shared 2465// memory. 2466bool os::can_commit_large_page_memory() { 2467 return UseHugeTLBFS; 2468} 2469 2470bool os::can_execute_large_page_memory() { 2471 return UseHugeTLBFS; 2472} 2473 2474// Reserve memory at an arbitrary address, only if that area is 2475// available (and not reserved for something else). 2476 2477char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2478 const int max_tries = 10; 2479 char* base[max_tries]; 2480 size_t size[max_tries]; 2481 const size_t gap = 0x000000; 2482 2483 // Assert only that the size is a multiple of the page size, since 2484 // that's all that mmap requires, and since that's all we really know 2485 // about at this low abstraction level. If we need higher alignment, 2486 // we can either pass an alignment to this method or verify alignment 2487 // in one of the methods further up the call chain. See bug 5044738. 2488 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2489 2490 // Repeatedly allocate blocks until the block is allocated at the 2491 // right spot. Give up after max_tries. Note that reserve_memory() will 2492 // automatically update _highest_vm_reserved_address if the call is 2493 // successful. The variable tracks the highest memory address every reserved 2494 // by JVM. It is used to detect heap-stack collision if running with 2495 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2496 // space than needed, it could confuse the collision detecting code. To 2497 // solve the problem, save current _highest_vm_reserved_address and 2498 // calculate the correct value before return. 2499 address old_highest = _highest_vm_reserved_address; 2500 2501 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2502 // if kernel honors the hint then we can return immediately. 2503 char * addr = anon_mmap(requested_addr, bytes, false); 2504 if (addr == requested_addr) { 2505 return requested_addr; 2506 } 2507 2508 if (addr != NULL) { 2509 // mmap() is successful but it fails to reserve at the requested address 2510 anon_munmap(addr, bytes); 2511 } 2512 2513 int i; 2514 for (i = 0; i < max_tries; ++i) { 2515 base[i] = reserve_memory(bytes); 2516 2517 if (base[i] != NULL) { 2518 // Is this the block we wanted? 2519 if (base[i] == requested_addr) { 2520 size[i] = bytes; 2521 break; 2522 } 2523 2524 // Does this overlap the block we wanted? Give back the overlapped 2525 // parts and try again. 2526 2527 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2528 if (top_overlap >= 0 && top_overlap < bytes) { 2529 unmap_memory(base[i], top_overlap); 2530 base[i] += top_overlap; 2531 size[i] = bytes - top_overlap; 2532 } else { 2533 size_t bottom_overlap = base[i] + bytes - requested_addr; 2534 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2535 unmap_memory(requested_addr, bottom_overlap); 2536 size[i] = bytes - bottom_overlap; 2537 } else { 2538 size[i] = bytes; 2539 } 2540 } 2541 } 2542 } 2543 2544 // Give back the unused reserved pieces. 2545 2546 for (int j = 0; j < i; ++j) { 2547 if (base[j] != NULL) { 2548 unmap_memory(base[j], size[j]); 2549 } 2550 } 2551 2552 if (i < max_tries) { 2553 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2554 return requested_addr; 2555 } else { 2556 _highest_vm_reserved_address = old_highest; 2557 return NULL; 2558 } 2559} 2560 2561size_t os::read(int fd, void *buf, unsigned int nBytes) { 2562 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2563} 2564 2565size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2566 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2567} 2568 2569void 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 } else { 2577 req.tv_nsec = 1; 2578 } 2579 2580 nanosleep(&req, NULL); 2581 2582 return; 2583} 2584 2585// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2586void os::infinite_sleep() { 2587 while (true) { // sleep forever ... 2588 ::sleep(100); // ... 100 seconds at a time 2589 } 2590} 2591 2592// Used to convert frequent JVM_Yield() to nops 2593bool os::dont_yield() { 2594 return DontYieldALot; 2595} 2596 2597void os::naked_yield() { 2598 sched_yield(); 2599} 2600 2601//////////////////////////////////////////////////////////////////////////////// 2602// thread priority support 2603 2604// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2605// only supports dynamic priority, static priority must be zero. For real-time 2606// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2607// However, for large multi-threaded applications, SCHED_RR is not only slower 2608// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2609// of 5 runs - Sep 2005). 2610// 2611// The following code actually changes the niceness of kernel-thread/LWP. It 2612// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2613// not the entire user process, and user level threads are 1:1 mapped to kernel 2614// threads. It has always been the case, but could change in the future. For 2615// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2616// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2617 2618#if !defined(__APPLE__) 2619int os::java_to_os_priority[CriticalPriority + 1] = { 2620 19, // 0 Entry should never be used 2621 2622 0, // 1 MinPriority 2623 3, // 2 2624 6, // 3 2625 2626 10, // 4 2627 15, // 5 NormPriority 2628 18, // 6 2629 2630 21, // 7 2631 25, // 8 2632 28, // 9 NearMaxPriority 2633 2634 31, // 10 MaxPriority 2635 2636 31 // 11 CriticalPriority 2637}; 2638#else 2639// Using Mach high-level priority assignments 2640int os::java_to_os_priority[CriticalPriority + 1] = { 2641 0, // 0 Entry should never be used (MINPRI_USER) 2642 2643 27, // 1 MinPriority 2644 28, // 2 2645 29, // 3 2646 2647 30, // 4 2648 31, // 5 NormPriority (BASEPRI_DEFAULT) 2649 32, // 6 2650 2651 33, // 7 2652 34, // 8 2653 35, // 9 NearMaxPriority 2654 2655 36, // 10 MaxPriority 2656 2657 36 // 11 CriticalPriority 2658}; 2659#endif 2660 2661static int prio_init() { 2662 if (ThreadPriorityPolicy == 1) { 2663 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2664 // if effective uid is not root. Perhaps, a more elegant way of doing 2665 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2666 if (geteuid() != 0) { 2667 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2668 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2669 } 2670 ThreadPriorityPolicy = 0; 2671 } 2672 } 2673 if (UseCriticalJavaThreadPriority) { 2674 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2675 } 2676 return 0; 2677} 2678 2679OSReturn os::set_native_priority(Thread* thread, int newpri) { 2680 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2681 2682#ifdef __OpenBSD__ 2683 // OpenBSD pthread_setprio starves low priority threads 2684 return OS_OK; 2685#elif defined(__FreeBSD__) 2686 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2687#elif defined(__APPLE__) || defined(__NetBSD__) 2688 struct sched_param sp; 2689 int policy; 2690 pthread_t self = pthread_self(); 2691 2692 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2693 return OS_ERR; 2694 } 2695 2696 sp.sched_priority = newpri; 2697 if (pthread_setschedparam(self, policy, &sp) != 0) { 2698 return OS_ERR; 2699 } 2700 2701 return OS_OK; 2702#else 2703 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2704 return (ret == 0) ? OS_OK : OS_ERR; 2705#endif 2706} 2707 2708OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2709 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2710 *priority_ptr = java_to_os_priority[NormPriority]; 2711 return OS_OK; 2712 } 2713 2714 errno = 0; 2715#if defined(__OpenBSD__) || defined(__FreeBSD__) 2716 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2717#elif defined(__APPLE__) || defined(__NetBSD__) 2718 int policy; 2719 struct sched_param sp; 2720 2721 pthread_getschedparam(pthread_self(), &policy, &sp); 2722 *priority_ptr = sp.sched_priority; 2723#else 2724 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2725#endif 2726 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2727} 2728 2729// Hint to the underlying OS that a task switch would not be good. 2730// Void return because it's a hint and can fail. 2731void os::hint_no_preempt() {} 2732 2733//////////////////////////////////////////////////////////////////////////////// 2734// suspend/resume support 2735 2736// the low-level signal-based suspend/resume support is a remnant from the 2737// old VM-suspension that used to be for java-suspension, safepoints etc, 2738// within hotspot. Now there is a single use-case for this: 2739// - calling get_thread_pc() on the VMThread by the flat-profiler task 2740// that runs in the watcher thread. 2741// The remaining code is greatly simplified from the more general suspension 2742// code that used to be used. 2743// 2744// The protocol is quite simple: 2745// - suspend: 2746// - sends a signal to the target thread 2747// - polls the suspend state of the osthread using a yield loop 2748// - target thread signal handler (SR_handler) sets suspend state 2749// and blocks in sigsuspend until continued 2750// - resume: 2751// - sets target osthread state to continue 2752// - sends signal to end the sigsuspend loop in the SR_handler 2753// 2754// Note that the SR_lock plays no role in this suspend/resume protocol. 2755 2756static void resume_clear_context(OSThread *osthread) { 2757 osthread->set_ucontext(NULL); 2758 osthread->set_siginfo(NULL); 2759} 2760 2761static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2762 osthread->set_ucontext(context); 2763 osthread->set_siginfo(siginfo); 2764} 2765 2766// Handler function invoked when a thread's execution is suspended or 2767// resumed. We have to be careful that only async-safe functions are 2768// called here (Note: most pthread functions are not async safe and 2769// should be avoided.) 2770// 2771// Note: sigwait() is a more natural fit than sigsuspend() from an 2772// interface point of view, but sigwait() prevents the signal hander 2773// from being run. libpthread would get very confused by not having 2774// its signal handlers run and prevents sigwait()'s use with the 2775// mutex granting granting signal. 2776// 2777// Currently only ever called on the VMThread or JavaThread 2778// 2779static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2780 // Save and restore errno to avoid confusing native code with EINTR 2781 // after sigsuspend. 2782 int old_errno = errno; 2783 2784 Thread* thread = Thread::current(); 2785 OSThread* osthread = thread->osthread(); 2786 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2787 2788 os::SuspendResume::State current = osthread->sr.state(); 2789 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2790 suspend_save_context(osthread, siginfo, context); 2791 2792 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2793 os::SuspendResume::State state = osthread->sr.suspended(); 2794 if (state == os::SuspendResume::SR_SUSPENDED) { 2795 sigset_t suspend_set; // signals for sigsuspend() 2796 2797 // get current set of blocked signals and unblock resume signal 2798 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2799 sigdelset(&suspend_set, SR_signum); 2800 2801 sr_semaphore.signal(); 2802 // wait here until we are resumed 2803 while (1) { 2804 sigsuspend(&suspend_set); 2805 2806 os::SuspendResume::State result = osthread->sr.running(); 2807 if (result == os::SuspendResume::SR_RUNNING) { 2808 sr_semaphore.signal(); 2809 break; 2810 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2811 ShouldNotReachHere(); 2812 } 2813 } 2814 2815 } else if (state == os::SuspendResume::SR_RUNNING) { 2816 // request was cancelled, continue 2817 } else { 2818 ShouldNotReachHere(); 2819 } 2820 2821 resume_clear_context(osthread); 2822 } else if (current == os::SuspendResume::SR_RUNNING) { 2823 // request was cancelled, continue 2824 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2825 // ignore 2826 } else { 2827 // ignore 2828 } 2829 2830 errno = old_errno; 2831} 2832 2833 2834static int SR_initialize() { 2835 struct sigaction act; 2836 char *s; 2837 // Get signal number to use for suspend/resume 2838 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2839 int sig = ::strtol(s, 0, 10); 2840 if (sig > 0 || sig < NSIG) { 2841 SR_signum = sig; 2842 } 2843 } 2844 2845 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2846 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2847 2848 sigemptyset(&SR_sigset); 2849 sigaddset(&SR_sigset, SR_signum); 2850 2851 // Set up signal handler for suspend/resume 2852 act.sa_flags = SA_RESTART|SA_SIGINFO; 2853 act.sa_handler = (void (*)(int)) SR_handler; 2854 2855 // SR_signum is blocked by default. 2856 // 4528190 - We also need to block pthread restart signal (32 on all 2857 // supported Bsd platforms). Note that BsdThreads need to block 2858 // this signal for all threads to work properly. So we don't have 2859 // to use hard-coded signal number when setting up the mask. 2860 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2861 2862 if (sigaction(SR_signum, &act, 0) == -1) { 2863 return -1; 2864 } 2865 2866 // Save signal flag 2867 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2868 return 0; 2869} 2870 2871static int sr_notify(OSThread* osthread) { 2872 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2873 assert_status(status == 0, status, "pthread_kill"); 2874 return status; 2875} 2876 2877// "Randomly" selected value for how long we want to spin 2878// before bailing out on suspending a thread, also how often 2879// we send a signal to a thread we want to resume 2880static const int RANDOMLY_LARGE_INTEGER = 1000000; 2881static const int RANDOMLY_LARGE_INTEGER2 = 100; 2882 2883// returns true on success and false on error - really an error is fatal 2884// but this seems the normal response to library errors 2885static bool do_suspend(OSThread* osthread) { 2886 assert(osthread->sr.is_running(), "thread should be running"); 2887 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2888 2889 // mark as suspended and send signal 2890 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2891 // failed to switch, state wasn't running? 2892 ShouldNotReachHere(); 2893 return false; 2894 } 2895 2896 if (sr_notify(osthread) != 0) { 2897 ShouldNotReachHere(); 2898 } 2899 2900 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2901 while (true) { 2902 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2903 break; 2904 } else { 2905 // timeout 2906 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2907 if (cancelled == os::SuspendResume::SR_RUNNING) { 2908 return false; 2909 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2910 // make sure that we consume the signal on the semaphore as well 2911 sr_semaphore.wait(); 2912 break; 2913 } else { 2914 ShouldNotReachHere(); 2915 return false; 2916 } 2917 } 2918 } 2919 2920 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2921 return true; 2922} 2923 2924static void do_resume(OSThread* osthread) { 2925 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2926 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2927 2928 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2929 // failed to switch to WAKEUP_REQUEST 2930 ShouldNotReachHere(); 2931 return; 2932 } 2933 2934 while (true) { 2935 if (sr_notify(osthread) == 0) { 2936 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2937 if (osthread->sr.is_running()) { 2938 return; 2939 } 2940 } 2941 } else { 2942 ShouldNotReachHere(); 2943 } 2944 } 2945 2946 guarantee(osthread->sr.is_running(), "Must be running!"); 2947} 2948 2949/////////////////////////////////////////////////////////////////////////////////// 2950// signal handling (except suspend/resume) 2951 2952// This routine may be used by user applications as a "hook" to catch signals. 2953// The user-defined signal handler must pass unrecognized signals to this 2954// routine, and if it returns true (non-zero), then the signal handler must 2955// return immediately. If the flag "abort_if_unrecognized" is true, then this 2956// routine will never retun false (zero), but instead will execute a VM panic 2957// routine kill the process. 2958// 2959// If this routine returns false, it is OK to call it again. This allows 2960// the user-defined signal handler to perform checks either before or after 2961// the VM performs its own checks. Naturally, the user code would be making 2962// a serious error if it tried to handle an exception (such as a null check 2963// or breakpoint) that the VM was generating for its own correct operation. 2964// 2965// This routine may recognize any of the following kinds of signals: 2966// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2967// It should be consulted by handlers for any of those signals. 2968// 2969// The caller of this routine must pass in the three arguments supplied 2970// to the function referred to in the "sa_sigaction" (not the "sa_handler") 2971// field of the structure passed to sigaction(). This routine assumes that 2972// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2973// 2974// Note that the VM will print warnings if it detects conflicting signal 2975// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2976// 2977extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2978 void* ucontext, 2979 int abort_if_unrecognized); 2980 2981void signalHandler(int sig, siginfo_t* info, void* uc) { 2982 assert(info != NULL && uc != NULL, "it must be old kernel"); 2983 int orig_errno = errno; // Preserve errno value over signal handler. 2984 JVM_handle_bsd_signal(sig, info, uc, true); 2985 errno = orig_errno; 2986} 2987 2988 2989// This boolean allows users to forward their own non-matching signals 2990// to JVM_handle_bsd_signal, harmlessly. 2991bool os::Bsd::signal_handlers_are_installed = false; 2992 2993// For signal-chaining 2994struct sigaction os::Bsd::sigact[MAXSIGNUM]; 2995unsigned int os::Bsd::sigs = 0; 2996bool os::Bsd::libjsig_is_loaded = false; 2997typedef struct sigaction *(*get_signal_t)(int); 2998get_signal_t os::Bsd::get_signal_action = NULL; 2999 3000struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3001 struct sigaction *actp = NULL; 3002 3003 if (libjsig_is_loaded) { 3004 // Retrieve the old signal handler from libjsig 3005 actp = (*get_signal_action)(sig); 3006 } 3007 if (actp == NULL) { 3008 // Retrieve the preinstalled signal handler from jvm 3009 actp = get_preinstalled_handler(sig); 3010 } 3011 3012 return actp; 3013} 3014 3015static bool call_chained_handler(struct sigaction *actp, int sig, 3016 siginfo_t *siginfo, void *context) { 3017 // Call the old signal handler 3018 if (actp->sa_handler == SIG_DFL) { 3019 // It's more reasonable to let jvm treat it as an unexpected exception 3020 // instead of taking the default action. 3021 return false; 3022 } else if (actp->sa_handler != SIG_IGN) { 3023 if ((actp->sa_flags & SA_NODEFER) == 0) { 3024 // automaticlly block the signal 3025 sigaddset(&(actp->sa_mask), sig); 3026 } 3027 3028 sa_handler_t hand; 3029 sa_sigaction_t sa; 3030 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3031 // retrieve the chained handler 3032 if (siginfo_flag_set) { 3033 sa = actp->sa_sigaction; 3034 } else { 3035 hand = actp->sa_handler; 3036 } 3037 3038 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3039 actp->sa_handler = SIG_DFL; 3040 } 3041 3042 // try to honor the signal mask 3043 sigset_t oset; 3044 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3045 3046 // call into the chained handler 3047 if (siginfo_flag_set) { 3048 (*sa)(sig, siginfo, context); 3049 } else { 3050 (*hand)(sig); 3051 } 3052 3053 // restore the signal mask 3054 pthread_sigmask(SIG_SETMASK, &oset, 0); 3055 } 3056 // Tell jvm's signal handler the signal is taken care of. 3057 return true; 3058} 3059 3060bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3061 bool chained = false; 3062 // signal-chaining 3063 if (UseSignalChaining) { 3064 struct sigaction *actp = get_chained_signal_action(sig); 3065 if (actp != NULL) { 3066 chained = call_chained_handler(actp, sig, siginfo, context); 3067 } 3068 } 3069 return chained; 3070} 3071 3072struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3073 if ((((unsigned int)1 << sig) & sigs) != 0) { 3074 return &sigact[sig]; 3075 } 3076 return NULL; 3077} 3078 3079void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3080 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3081 sigact[sig] = oldAct; 3082 sigs |= (unsigned int)1 << sig; 3083} 3084 3085// for diagnostic 3086int os::Bsd::sigflags[MAXSIGNUM]; 3087 3088int os::Bsd::get_our_sigflags(int sig) { 3089 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3090 return sigflags[sig]; 3091} 3092 3093void os::Bsd::set_our_sigflags(int sig, int flags) { 3094 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3095 sigflags[sig] = flags; 3096} 3097 3098void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3099 // Check for overwrite. 3100 struct sigaction oldAct; 3101 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3102 3103 void* oldhand = oldAct.sa_sigaction 3104 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3105 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3106 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3107 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3108 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3109 if (AllowUserSignalHandlers || !set_installed) { 3110 // Do not overwrite; user takes responsibility to forward to us. 3111 return; 3112 } else if (UseSignalChaining) { 3113 // save the old handler in jvm 3114 save_preinstalled_handler(sig, oldAct); 3115 // libjsig also interposes the sigaction() call below and saves the 3116 // old sigaction on it own. 3117 } else { 3118 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3119 "%#lx for signal %d.", (long)oldhand, sig)); 3120 } 3121 } 3122 3123 struct sigaction sigAct; 3124 sigfillset(&(sigAct.sa_mask)); 3125 sigAct.sa_handler = SIG_DFL; 3126 if (!set_installed) { 3127 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3128 } else { 3129 sigAct.sa_sigaction = signalHandler; 3130 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3131 } 3132#ifdef __APPLE__ 3133 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3134 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3135 // if the signal handler declares it will handle it on alternate stack. 3136 // Notice we only declare we will handle it on alt stack, but we are not 3137 // actually going to use real alt stack - this is just a workaround. 3138 // Please see ux_exception.c, method catch_mach_exception_raise for details 3139 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3140 if (sig == SIGSEGV) { 3141 sigAct.sa_flags |= SA_ONSTACK; 3142 } 3143#endif 3144 3145 // Save flags, which are set by ours 3146 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3147 sigflags[sig] = sigAct.sa_flags; 3148 3149 int ret = sigaction(sig, &sigAct, &oldAct); 3150 assert(ret == 0, "check"); 3151 3152 void* oldhand2 = oldAct.sa_sigaction 3153 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3154 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3155 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3156} 3157 3158// install signal handlers for signals that HotSpot needs to 3159// handle in order to support Java-level exception handling. 3160 3161void os::Bsd::install_signal_handlers() { 3162 if (!signal_handlers_are_installed) { 3163 signal_handlers_are_installed = true; 3164 3165 // signal-chaining 3166 typedef void (*signal_setting_t)(); 3167 signal_setting_t begin_signal_setting = NULL; 3168 signal_setting_t end_signal_setting = NULL; 3169 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3170 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3171 if (begin_signal_setting != NULL) { 3172 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3173 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3174 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3175 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3176 libjsig_is_loaded = true; 3177 assert(UseSignalChaining, "should enable signal-chaining"); 3178 } 3179 if (libjsig_is_loaded) { 3180 // Tell libjsig jvm is setting signal handlers 3181 (*begin_signal_setting)(); 3182 } 3183 3184 set_signal_handler(SIGSEGV, true); 3185 set_signal_handler(SIGPIPE, true); 3186 set_signal_handler(SIGBUS, true); 3187 set_signal_handler(SIGILL, true); 3188 set_signal_handler(SIGFPE, true); 3189 set_signal_handler(SIGXFSZ, true); 3190 3191#if defined(__APPLE__) 3192 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3193 // signals caught and handled by the JVM. To work around this, we reset the mach task 3194 // signal handler that's placed on our process by CrashReporter. This disables 3195 // CrashReporter-based reporting. 3196 // 3197 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3198 // on caught fatal signals. 3199 // 3200 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3201 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3202 // exception handling, while leaving the standard BSD signal handlers functional. 3203 kern_return_t kr; 3204 kr = task_set_exception_ports(mach_task_self(), 3205 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3206 MACH_PORT_NULL, 3207 EXCEPTION_STATE_IDENTITY, 3208 MACHINE_THREAD_STATE); 3209 3210 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3211#endif 3212 3213 if (libjsig_is_loaded) { 3214 // Tell libjsig jvm finishes setting signal handlers 3215 (*end_signal_setting)(); 3216 } 3217 3218 // We don't activate signal checker if libjsig is in place, we trust ourselves 3219 // and if UserSignalHandler is installed all bets are off 3220 if (CheckJNICalls) { 3221 if (libjsig_is_loaded) { 3222 if (PrintJNIResolving) { 3223 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3224 } 3225 check_signals = false; 3226 } 3227 if (AllowUserSignalHandlers) { 3228 if (PrintJNIResolving) { 3229 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3230 } 3231 check_signals = false; 3232 } 3233 } 3234 } 3235} 3236 3237 3238///// 3239// glibc on Bsd platform uses non-documented flag 3240// to indicate, that some special sort of signal 3241// trampoline is used. 3242// We will never set this flag, and we should 3243// ignore this flag in our diagnostic 3244#ifdef SIGNIFICANT_SIGNAL_MASK 3245 #undef SIGNIFICANT_SIGNAL_MASK 3246#endif 3247#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3248 3249static const char* get_signal_handler_name(address handler, 3250 char* buf, int buflen) { 3251 int offset; 3252 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3253 if (found) { 3254 // skip directory names 3255 const char *p1, *p2; 3256 p1 = buf; 3257 size_t len = strlen(os::file_separator()); 3258 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3259 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3260 } else { 3261 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3262 } 3263 return buf; 3264} 3265 3266static void print_signal_handler(outputStream* st, int sig, 3267 char* buf, size_t buflen) { 3268 struct sigaction sa; 3269 3270 sigaction(sig, NULL, &sa); 3271 3272 // See comment for SIGNIFICANT_SIGNAL_MASK define 3273 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3274 3275 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3276 3277 address handler = (sa.sa_flags & SA_SIGINFO) 3278 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3279 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3280 3281 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3282 st->print("SIG_DFL"); 3283 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3284 st->print("SIG_IGN"); 3285 } else { 3286 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3287 } 3288 3289 st->print(", sa_mask[0]="); 3290 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3291 3292 address rh = VMError::get_resetted_sighandler(sig); 3293 // May be, handler was resetted by VMError? 3294 if (rh != NULL) { 3295 handler = rh; 3296 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3297 } 3298 3299 st->print(", sa_flags="); 3300 os::Posix::print_sa_flags(st, sa.sa_flags); 3301 3302 // Check: is it our handler? 3303 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3304 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3305 // It is our signal handler 3306 // check for flags, reset system-used one! 3307 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3308 st->print( 3309 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3310 os::Bsd::get_our_sigflags(sig)); 3311 } 3312 } 3313 st->cr(); 3314} 3315 3316 3317#define DO_SIGNAL_CHECK(sig) \ 3318 do { \ 3319 if (!sigismember(&check_signal_done, sig)) { \ 3320 os::Bsd::check_signal_handler(sig); \ 3321 } \ 3322 } while (0) 3323 3324// This method is a periodic task to check for misbehaving JNI applications 3325// under CheckJNI, we can add any periodic checks here 3326 3327void os::run_periodic_checks() { 3328 3329 if (check_signals == false) return; 3330 3331 // SEGV and BUS if overridden could potentially prevent 3332 // generation of hs*.log in the event of a crash, debugging 3333 // such a case can be very challenging, so we absolutely 3334 // check the following for a good measure: 3335 DO_SIGNAL_CHECK(SIGSEGV); 3336 DO_SIGNAL_CHECK(SIGILL); 3337 DO_SIGNAL_CHECK(SIGFPE); 3338 DO_SIGNAL_CHECK(SIGBUS); 3339 DO_SIGNAL_CHECK(SIGPIPE); 3340 DO_SIGNAL_CHECK(SIGXFSZ); 3341 3342 3343 // ReduceSignalUsage allows the user to override these handlers 3344 // see comments at the very top and jvm_solaris.h 3345 if (!ReduceSignalUsage) { 3346 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3347 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3348 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3349 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3350 } 3351 3352 DO_SIGNAL_CHECK(SR_signum); 3353 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3354} 3355 3356typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3357 3358static os_sigaction_t os_sigaction = NULL; 3359 3360void os::Bsd::check_signal_handler(int sig) { 3361 char buf[O_BUFLEN]; 3362 address jvmHandler = NULL; 3363 3364 3365 struct sigaction act; 3366 if (os_sigaction == NULL) { 3367 // only trust the default sigaction, in case it has been interposed 3368 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3369 if (os_sigaction == NULL) return; 3370 } 3371 3372 os_sigaction(sig, (struct sigaction*)NULL, &act); 3373 3374 3375 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3376 3377 address thisHandler = (act.sa_flags & SA_SIGINFO) 3378 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3379 : CAST_FROM_FN_PTR(address, act.sa_handler); 3380 3381 3382 switch (sig) { 3383 case SIGSEGV: 3384 case SIGBUS: 3385 case SIGFPE: 3386 case SIGPIPE: 3387 case SIGILL: 3388 case SIGXFSZ: 3389 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3390 break; 3391 3392 case SHUTDOWN1_SIGNAL: 3393 case SHUTDOWN2_SIGNAL: 3394 case SHUTDOWN3_SIGNAL: 3395 case BREAK_SIGNAL: 3396 jvmHandler = (address)user_handler(); 3397 break; 3398 3399 case INTERRUPT_SIGNAL: 3400 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3401 break; 3402 3403 default: 3404 if (sig == SR_signum) { 3405 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3406 } else { 3407 return; 3408 } 3409 break; 3410 } 3411 3412 if (thisHandler != jvmHandler) { 3413 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3414 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3415 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3416 // No need to check this sig any longer 3417 sigaddset(&check_signal_done, sig); 3418 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3419 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3420 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3421 exception_name(sig, buf, O_BUFLEN)); 3422 } 3423 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3424 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3425 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3426 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3427 // No need to check this sig any longer 3428 sigaddset(&check_signal_done, sig); 3429 } 3430 3431 // Dump all the signal 3432 if (sigismember(&check_signal_done, sig)) { 3433 print_signal_handlers(tty, buf, O_BUFLEN); 3434 } 3435} 3436 3437extern void report_error(char* file_name, int line_no, char* title, 3438 char* format, ...); 3439 3440extern bool signal_name(int signo, char* buf, size_t len); 3441 3442const char* os::exception_name(int exception_code, char* buf, size_t size) { 3443 if (0 < exception_code && exception_code <= SIGRTMAX) { 3444 // signal 3445 if (!signal_name(exception_code, buf, size)) { 3446 jio_snprintf(buf, size, "SIG%d", exception_code); 3447 } 3448 return buf; 3449 } else { 3450 return NULL; 3451 } 3452} 3453 3454// this is called _before_ the most of global arguments have been parsed 3455void os::init(void) { 3456 char dummy; // used to get a guess on initial stack address 3457// first_hrtime = gethrtime(); 3458 3459 // With BsdThreads the JavaMain thread pid (primordial thread) 3460 // is different than the pid of the java launcher thread. 3461 // So, on Bsd, the launcher thread pid is passed to the VM 3462 // via the sun.java.launcher.pid property. 3463 // Use this property instead of getpid() if it was correctly passed. 3464 // See bug 6351349. 3465 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3466 3467 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3468 3469 clock_tics_per_sec = CLK_TCK; 3470 3471 init_random(1234567); 3472 3473 ThreadCritical::initialize(); 3474 3475 Bsd::set_page_size(getpagesize()); 3476 if (Bsd::page_size() == -1) { 3477 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3478 strerror(errno))); 3479 } 3480 init_page_sizes((size_t) Bsd::page_size()); 3481 3482 Bsd::initialize_system_info(); 3483 3484 // main_thread points to the aboriginal thread 3485 Bsd::_main_thread = pthread_self(); 3486 3487 Bsd::clock_init(); 3488 initial_time_count = javaTimeNanos(); 3489 3490#ifdef __APPLE__ 3491 // XXXDARWIN 3492 // Work around the unaligned VM callbacks in hotspot's 3493 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3494 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3495 // alignment when doing symbol lookup. To work around this, we force early 3496 // binding of all symbols now, thus binding when alignment is known-good. 3497 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3498#endif 3499} 3500 3501// To install functions for atexit system call 3502extern "C" { 3503 static void perfMemory_exit_helper() { 3504 perfMemory_exit(); 3505 } 3506} 3507 3508// this is called _after_ the global arguments have been parsed 3509jint os::init_2(void) { 3510 // Allocate a single page and mark it as readable for safepoint polling 3511 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3512 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3513 3514 os::set_polling_page(polling_page); 3515 3516#ifndef PRODUCT 3517 if (Verbose && PrintMiscellaneous) { 3518 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", 3519 (intptr_t)polling_page); 3520 } 3521#endif 3522 3523 if (!UseMembar) { 3524 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3525 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3526 os::set_memory_serialize_page(mem_serialize_page); 3527 3528#ifndef PRODUCT 3529 if (Verbose && PrintMiscellaneous) { 3530 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", 3531 (intptr_t)mem_serialize_page); 3532 } 3533#endif 3534 } 3535 3536 // initialize suspend/resume support - must do this before signal_sets_init() 3537 if (SR_initialize() != 0) { 3538 perror("SR_initialize failed"); 3539 return JNI_ERR; 3540 } 3541 3542 Bsd::signal_sets_init(); 3543 Bsd::install_signal_handlers(); 3544 3545 // Check minimum allowable stack size for thread creation and to initialize 3546 // the java system classes, including StackOverflowError - depends on page 3547 // size. Add a page for compiler2 recursion in main thread. 3548 // Add in 2*BytesPerWord times page size to account for VM stack during 3549 // class initialization depending on 32 or 64 bit VM. 3550 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3551 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3552 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3553 3554 size_t threadStackSizeInBytes = ThreadStackSize * K; 3555 if (threadStackSizeInBytes != 0 && 3556 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3557 tty->print_cr("\nThe stack size specified is too small, " 3558 "Specify at least %dk", 3559 os::Bsd::min_stack_allowed/ K); 3560 return JNI_ERR; 3561 } 3562 3563 // Make the stack size a multiple of the page size so that 3564 // the yellow/red zones can be guarded. 3565 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3566 vm_page_size())); 3567 3568 if (MaxFDLimit) { 3569 // set the number of file descriptors to max. print out error 3570 // if getrlimit/setrlimit fails but continue regardless. 3571 struct rlimit nbr_files; 3572 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3573 if (status != 0) { 3574 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3575 perror("os::init_2 getrlimit failed"); 3576 } 3577 } else { 3578 nbr_files.rlim_cur = nbr_files.rlim_max; 3579 3580#ifdef __APPLE__ 3581 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3582 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3583 // be used instead 3584 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3585#endif 3586 3587 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3588 if (status != 0) { 3589 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3590 perror("os::init_2 setrlimit failed"); 3591 } 3592 } 3593 } 3594 } 3595 3596 // at-exit methods are called in the reverse order of their registration. 3597 // atexit functions are called on return from main or as a result of a 3598 // call to exit(3C). There can be only 32 of these functions registered 3599 // and atexit() does not set errno. 3600 3601 if (PerfAllowAtExitRegistration) { 3602 // only register atexit functions if PerfAllowAtExitRegistration is set. 3603 // atexit functions can be delayed until process exit time, which 3604 // can be problematic for embedded VM situations. Embedded VMs should 3605 // call DestroyJavaVM() to assure that VM resources are released. 3606 3607 // note: perfMemory_exit_helper atexit function may be removed in 3608 // the future if the appropriate cleanup code can be added to the 3609 // VM_Exit VMOperation's doit method. 3610 if (atexit(perfMemory_exit_helper) != 0) { 3611 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3612 } 3613 } 3614 3615 // initialize thread priority policy 3616 prio_init(); 3617 3618#ifdef __APPLE__ 3619 // dynamically link to objective c gc registration 3620 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3621 if (handleLibObjc != NULL) { 3622 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3623 } 3624#endif 3625 3626 return JNI_OK; 3627} 3628 3629// Mark the polling page as unreadable 3630void os::make_polling_page_unreadable(void) { 3631 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3632 fatal("Could not disable polling page"); 3633 } 3634} 3635 3636// Mark the polling page as readable 3637void os::make_polling_page_readable(void) { 3638 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3639 fatal("Could not enable polling page"); 3640 } 3641} 3642 3643int os::active_processor_count() { 3644 return _processor_count; 3645} 3646 3647void os::set_native_thread_name(const char *name) { 3648#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3649 // This is only supported in Snow Leopard and beyond 3650 if (name != NULL) { 3651 // Add a "Java: " prefix to the name 3652 char buf[MAXTHREADNAMESIZE]; 3653 snprintf(buf, sizeof(buf), "Java: %s", name); 3654 pthread_setname_np(buf); 3655 } 3656#endif 3657} 3658 3659bool os::distribute_processes(uint length, uint* distribution) { 3660 // Not yet implemented. 3661 return false; 3662} 3663 3664bool os::bind_to_processor(uint processor_id) { 3665 // Not yet implemented. 3666 return false; 3667} 3668 3669void os::SuspendedThreadTask::internal_do_task() { 3670 if (do_suspend(_thread->osthread())) { 3671 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3672 do_task(context); 3673 do_resume(_thread->osthread()); 3674 } 3675} 3676 3677/// 3678class PcFetcher : public os::SuspendedThreadTask { 3679 public: 3680 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3681 ExtendedPC result(); 3682 protected: 3683 void do_task(const os::SuspendedThreadTaskContext& context); 3684 private: 3685 ExtendedPC _epc; 3686}; 3687 3688ExtendedPC PcFetcher::result() { 3689 guarantee(is_done(), "task is not done yet."); 3690 return _epc; 3691} 3692 3693void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3694 Thread* thread = context.thread(); 3695 OSThread* osthread = thread->osthread(); 3696 if (osthread->ucontext() != NULL) { 3697 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3698 } else { 3699 // NULL context is unexpected, double-check this is the VMThread 3700 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3701 } 3702} 3703 3704// Suspends the target using the signal mechanism and then grabs the PC before 3705// resuming the target. Used by the flat-profiler only 3706ExtendedPC os::get_thread_pc(Thread* thread) { 3707 // Make sure that it is called by the watcher for the VMThread 3708 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3709 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3710 3711 PcFetcher fetcher(thread); 3712 fetcher.run(); 3713 return fetcher.result(); 3714} 3715 3716int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, 3717 pthread_mutex_t *_mutex, 3718 const struct timespec *_abstime) { 3719 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3720} 3721 3722//////////////////////////////////////////////////////////////////////////////// 3723// debug support 3724 3725bool os::find(address addr, outputStream* st) { 3726 Dl_info dlinfo; 3727 memset(&dlinfo, 0, sizeof(dlinfo)); 3728 if (dladdr(addr, &dlinfo) != 0) { 3729 st->print(PTR_FORMAT ": ", addr); 3730 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3731 st->print("%s+%#x", dlinfo.dli_sname, 3732 addr - (intptr_t)dlinfo.dli_saddr); 3733 } else if (dlinfo.dli_fbase != NULL) { 3734 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3735 } else { 3736 st->print("<absolute address>"); 3737 } 3738 if (dlinfo.dli_fname != NULL) { 3739 st->print(" in %s", dlinfo.dli_fname); 3740 } 3741 if (dlinfo.dli_fbase != NULL) { 3742 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3743 } 3744 st->cr(); 3745 3746 if (Verbose) { 3747 // decode some bytes around the PC 3748 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3749 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3750 address lowest = (address) dlinfo.dli_sname; 3751 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3752 if (begin < lowest) begin = lowest; 3753 Dl_info dlinfo2; 3754 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3755 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3756 end = (address) dlinfo2.dli_saddr; 3757 } 3758 Disassembler::decode(begin, end, st); 3759 } 3760 return true; 3761 } 3762 return false; 3763} 3764 3765//////////////////////////////////////////////////////////////////////////////// 3766// misc 3767 3768// This does not do anything on Bsd. This is basically a hook for being 3769// able to use structured exception handling (thread-local exception filters) 3770// on, e.g., Win32. 3771void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3772 methodHandle* method, JavaCallArguments* args, 3773 Thread* thread) { 3774 f(value, method, args, thread); 3775} 3776 3777void os::print_statistics() { 3778} 3779 3780int os::message_box(const char* title, const char* message) { 3781 int i; 3782 fdStream err(defaultStream::error_fd()); 3783 for (i = 0; i < 78; i++) err.print_raw("="); 3784 err.cr(); 3785 err.print_raw_cr(title); 3786 for (i = 0; i < 78; i++) err.print_raw("-"); 3787 err.cr(); 3788 err.print_raw_cr(message); 3789 for (i = 0; i < 78; i++) err.print_raw("="); 3790 err.cr(); 3791 3792 char buf[16]; 3793 // Prevent process from exiting upon "read error" without consuming all CPU 3794 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3795 3796 return buf[0] == 'y' || buf[0] == 'Y'; 3797} 3798 3799int os::stat(const char *path, struct stat *sbuf) { 3800 char pathbuf[MAX_PATH]; 3801 if (strlen(path) > MAX_PATH - 1) { 3802 errno = ENAMETOOLONG; 3803 return -1; 3804 } 3805 os::native_path(strcpy(pathbuf, path)); 3806 return ::stat(pathbuf, sbuf); 3807} 3808 3809bool os::check_heap(bool force) { 3810 return true; 3811} 3812 3813// Is a (classpath) directory empty? 3814bool os::dir_is_empty(const char* path) { 3815 DIR *dir = NULL; 3816 struct dirent *ptr; 3817 3818 dir = opendir(path); 3819 if (dir == NULL) return true; 3820 3821 // Scan the directory 3822 bool result = true; 3823 char buf[sizeof(struct dirent) + MAX_PATH]; 3824 while (result && (ptr = ::readdir(dir)) != NULL) { 3825 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3826 result = false; 3827 } 3828 } 3829 closedir(dir); 3830 return result; 3831} 3832 3833// This code originates from JDK's sysOpen and open64_w 3834// from src/solaris/hpi/src/system_md.c 3835 3836int os::open(const char *path, int oflag, int mode) { 3837 if (strlen(path) > MAX_PATH - 1) { 3838 errno = ENAMETOOLONG; 3839 return -1; 3840 } 3841 int fd; 3842 3843 fd = ::open(path, oflag, mode); 3844 if (fd == -1) return -1; 3845 3846 // If the open succeeded, the file might still be a directory 3847 { 3848 struct stat buf; 3849 int ret = ::fstat(fd, &buf); 3850 int st_mode = buf.st_mode; 3851 3852 if (ret != -1) { 3853 if ((st_mode & S_IFMT) == S_IFDIR) { 3854 errno = EISDIR; 3855 ::close(fd); 3856 return -1; 3857 } 3858 } else { 3859 ::close(fd); 3860 return -1; 3861 } 3862 } 3863 3864 // All file descriptors that are opened in the JVM and not 3865 // specifically destined for a subprocess should have the 3866 // close-on-exec flag set. If we don't set it, then careless 3rd 3867 // party native code might fork and exec without closing all 3868 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3869 // UNIXProcess.c), and this in turn might: 3870 // 3871 // - cause end-of-file to fail to be detected on some file 3872 // descriptors, resulting in mysterious hangs, or 3873 // 3874 // - might cause an fopen in the subprocess to fail on a system 3875 // suffering from bug 1085341. 3876 // 3877 // (Yes, the default setting of the close-on-exec flag is a Unix 3878 // design flaw) 3879 // 3880 // See: 3881 // 1085341: 32-bit stdio routines should support file descriptors >255 3882 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3883 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3884 // 3885#ifdef FD_CLOEXEC 3886 { 3887 int flags = ::fcntl(fd, F_GETFD); 3888 if (flags != -1) { 3889 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3890 } 3891 } 3892#endif 3893 3894 return fd; 3895} 3896 3897 3898// create binary file, rewriting existing file if required 3899int os::create_binary_file(const char* path, bool rewrite_existing) { 3900 int oflags = O_WRONLY | O_CREAT; 3901 if (!rewrite_existing) { 3902 oflags |= O_EXCL; 3903 } 3904 return ::open(path, oflags, S_IREAD | S_IWRITE); 3905} 3906 3907// return current position of file pointer 3908jlong os::current_file_offset(int fd) { 3909 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3910} 3911 3912// move file pointer to the specified offset 3913jlong os::seek_to_file_offset(int fd, jlong offset) { 3914 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3915} 3916 3917// This code originates from JDK's sysAvailable 3918// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3919 3920int os::available(int fd, jlong *bytes) { 3921 jlong cur, end; 3922 int mode; 3923 struct stat buf; 3924 3925 if (::fstat(fd, &buf) >= 0) { 3926 mode = buf.st_mode; 3927 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3928 // XXX: is the following call interruptible? If so, this might 3929 // need to go through the INTERRUPT_IO() wrapper as for other 3930 // blocking, interruptible calls in this file. 3931 int n; 3932 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3933 *bytes = n; 3934 return 1; 3935 } 3936 } 3937 } 3938 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3939 return 0; 3940 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3941 return 0; 3942 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3943 return 0; 3944 } 3945 *bytes = end - cur; 3946 return 1; 3947} 3948 3949// Map a block of memory. 3950char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3951 char *addr, size_t bytes, bool read_only, 3952 bool allow_exec) { 3953 int prot; 3954 int flags; 3955 3956 if (read_only) { 3957 prot = PROT_READ; 3958 flags = MAP_SHARED; 3959 } else { 3960 prot = PROT_READ | PROT_WRITE; 3961 flags = MAP_PRIVATE; 3962 } 3963 3964 if (allow_exec) { 3965 prot |= PROT_EXEC; 3966 } 3967 3968 if (addr != NULL) { 3969 flags |= MAP_FIXED; 3970 } 3971 3972 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3973 fd, file_offset); 3974 if (mapped_address == MAP_FAILED) { 3975 return NULL; 3976 } 3977 return mapped_address; 3978} 3979 3980 3981// Remap a block of memory. 3982char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3983 char *addr, size_t bytes, bool read_only, 3984 bool allow_exec) { 3985 // same as map_memory() on this OS 3986 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3987 allow_exec); 3988} 3989 3990 3991// Unmap a block of memory. 3992bool os::pd_unmap_memory(char* addr, size_t bytes) { 3993 return munmap(addr, bytes) == 0; 3994} 3995 3996// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3997// are used by JVM M&M and JVMTI to get user+sys or user CPU time 3998// of a thread. 3999// 4000// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4001// the fast estimate available on the platform. 4002 4003jlong os::current_thread_cpu_time() { 4004#ifdef __APPLE__ 4005 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4006#else 4007 Unimplemented(); 4008 return 0; 4009#endif 4010} 4011 4012jlong os::thread_cpu_time(Thread* thread) { 4013#ifdef __APPLE__ 4014 return os::thread_cpu_time(thread, true /* user + sys */); 4015#else 4016 Unimplemented(); 4017 return 0; 4018#endif 4019} 4020 4021jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4022#ifdef __APPLE__ 4023 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4024#else 4025 Unimplemented(); 4026 return 0; 4027#endif 4028} 4029 4030jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4031#ifdef __APPLE__ 4032 struct thread_basic_info tinfo; 4033 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4034 kern_return_t kr; 4035 thread_t mach_thread; 4036 4037 mach_thread = thread->osthread()->thread_id(); 4038 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4039 if (kr != KERN_SUCCESS) { 4040 return -1; 4041 } 4042 4043 if (user_sys_cpu_time) { 4044 jlong nanos; 4045 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4046 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4047 return nanos; 4048 } else { 4049 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4050 } 4051#else 4052 Unimplemented(); 4053 return 0; 4054#endif 4055} 4056 4057 4058void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4059 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4060 info_ptr->may_skip_backward = false; // elapsed time not wall time 4061 info_ptr->may_skip_forward = false; // elapsed time not wall time 4062 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4063} 4064 4065void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4066 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4067 info_ptr->may_skip_backward = false; // elapsed time not wall time 4068 info_ptr->may_skip_forward = false; // elapsed time not wall time 4069 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4070} 4071 4072bool os::is_thread_cpu_time_supported() { 4073#ifdef __APPLE__ 4074 return true; 4075#else 4076 return false; 4077#endif 4078} 4079 4080// System loadavg support. Returns -1 if load average cannot be obtained. 4081// Bsd doesn't yet have a (official) notion of processor sets, 4082// so just return the system wide load average. 4083int os::loadavg(double loadavg[], int nelem) { 4084 return ::getloadavg(loadavg, nelem); 4085} 4086 4087void os::pause() { 4088 char filename[MAX_PATH]; 4089 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4090 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4091 } else { 4092 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4093 } 4094 4095 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4096 if (fd != -1) { 4097 struct stat buf; 4098 ::close(fd); 4099 while (::stat(filename, &buf) == 0) { 4100 (void)::poll(NULL, 0, 100); 4101 } 4102 } else { 4103 jio_fprintf(stderr, 4104 "Could not open pause file '%s', continuing immediately.\n", filename); 4105 } 4106} 4107 4108 4109// Refer to the comments in os_solaris.cpp park-unpark. The next two 4110// comment paragraphs are worth repeating here: 4111// 4112// Assumption: 4113// Only one parker can exist on an event, which is why we allocate 4114// them per-thread. Multiple unparkers can coexist. 4115// 4116// _Event serves as a restricted-range semaphore. 4117// -1 : thread is blocked, i.e. there is a waiter 4118// 0 : neutral: thread is running or ready, 4119// could have been signaled after a wait started 4120// 1 : signaled - thread is running or ready 4121// 4122// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4123// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4124// For specifics regarding the bug see GLIBC BUGID 261237 : 4125// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4126// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4127// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4128// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4129// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4130// and monitorenter when we're using 1-0 locking. All those operations may result in 4131// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4132// of libpthread avoids the problem, but isn't practical. 4133// 4134// Possible remedies: 4135// 4136// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4137// This is palliative and probabilistic, however. If the thread is preempted 4138// between the call to compute_abstime() and pthread_cond_timedwait(), more 4139// than the minimum period may have passed, and the abstime may be stale (in the 4140// past) resultin in a hang. Using this technique reduces the odds of a hang 4141// but the JVM is still vulnerable, particularly on heavily loaded systems. 4142// 4143// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4144// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4145// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4146// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4147// thread. 4148// 4149// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4150// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4151// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4152// This also works well. In fact it avoids kernel-level scalability impediments 4153// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4154// timers in a graceful fashion. 4155// 4156// 4. When the abstime value is in the past it appears that control returns 4157// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4158// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4159// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4160// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4161// It may be possible to avoid reinitialization by checking the return 4162// value from pthread_cond_timedwait(). In addition to reinitializing the 4163// condvar we must establish the invariant that cond_signal() is only called 4164// within critical sections protected by the adjunct mutex. This prevents 4165// cond_signal() from "seeing" a condvar that's in the midst of being 4166// reinitialized or that is corrupt. Sadly, this invariant obviates the 4167// desirable signal-after-unlock optimization that avoids futile context switching. 4168// 4169// I'm also concerned that some versions of NTPL might allocate an auxilliary 4170// structure when a condvar is used or initialized. cond_destroy() would 4171// release the helper structure. Our reinitialize-after-timedwait fix 4172// put excessive stress on malloc/free and locks protecting the c-heap. 4173// 4174// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4175// It may be possible to refine (4) by checking the kernel and NTPL verisons 4176// and only enabling the work-around for vulnerable environments. 4177 4178// utility to compute the abstime argument to timedwait: 4179// millis is the relative timeout time 4180// abstime will be the absolute timeout time 4181// TODO: replace compute_abstime() with unpackTime() 4182 4183static struct timespec* compute_abstime(struct timespec* abstime, 4184 jlong millis) { 4185 if (millis < 0) millis = 0; 4186 struct timeval now; 4187 int status = gettimeofday(&now, NULL); 4188 assert(status == 0, "gettimeofday"); 4189 jlong seconds = millis / 1000; 4190 millis %= 1000; 4191 if (seconds > 50000000) { // see man cond_timedwait(3T) 4192 seconds = 50000000; 4193 } 4194 abstime->tv_sec = now.tv_sec + seconds; 4195 long usec = now.tv_usec + millis * 1000; 4196 if (usec >= 1000000) { 4197 abstime->tv_sec += 1; 4198 usec -= 1000000; 4199 } 4200 abstime->tv_nsec = usec * 1000; 4201 return abstime; 4202} 4203 4204void os::PlatformEvent::park() { // AKA "down()" 4205 // Transitions for _Event: 4206 // -1 => -1 : illegal 4207 // 1 => 0 : pass - return immediately 4208 // 0 => -1 : block; then set _Event to 0 before returning 4209 4210 // Invariant: Only the thread associated with the Event/PlatformEvent 4211 // may call park(). 4212 // TODO: assert that _Assoc != NULL or _Assoc == Self 4213 assert(_nParked == 0, "invariant"); 4214 4215 int v; 4216 for (;;) { 4217 v = _Event; 4218 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4219 } 4220 guarantee(v >= 0, "invariant"); 4221 if (v == 0) { 4222 // Do this the hard way by blocking ... 4223 int status = pthread_mutex_lock(_mutex); 4224 assert_status(status == 0, status, "mutex_lock"); 4225 guarantee(_nParked == 0, "invariant"); 4226 ++_nParked; 4227 while (_Event < 0) { 4228 status = pthread_cond_wait(_cond, _mutex); 4229 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4230 // Treat this the same as if the wait was interrupted 4231 if (status == ETIMEDOUT) { status = EINTR; } 4232 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4233 } 4234 --_nParked; 4235 4236 _Event = 0; 4237 status = pthread_mutex_unlock(_mutex); 4238 assert_status(status == 0, status, "mutex_unlock"); 4239 // Paranoia to ensure our locked and lock-free paths interact 4240 // correctly with each other. 4241 OrderAccess::fence(); 4242 } 4243 guarantee(_Event >= 0, "invariant"); 4244} 4245 4246int os::PlatformEvent::park(jlong millis) { 4247 // Transitions for _Event: 4248 // -1 => -1 : illegal 4249 // 1 => 0 : pass - return immediately 4250 // 0 => -1 : block; then set _Event to 0 before returning 4251 4252 guarantee(_nParked == 0, "invariant"); 4253 4254 int v; 4255 for (;;) { 4256 v = _Event; 4257 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4258 } 4259 guarantee(v >= 0, "invariant"); 4260 if (v != 0) return OS_OK; 4261 4262 // We do this the hard way, by blocking the thread. 4263 // Consider enforcing a minimum timeout value. 4264 struct timespec abst; 4265 compute_abstime(&abst, millis); 4266 4267 int ret = OS_TIMEOUT; 4268 int status = pthread_mutex_lock(_mutex); 4269 assert_status(status == 0, status, "mutex_lock"); 4270 guarantee(_nParked == 0, "invariant"); 4271 ++_nParked; 4272 4273 // Object.wait(timo) will return because of 4274 // (a) notification 4275 // (b) timeout 4276 // (c) thread.interrupt 4277 // 4278 // Thread.interrupt and object.notify{All} both call Event::set. 4279 // That is, we treat thread.interrupt as a special case of notification. 4280 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4281 // We assume all ETIME returns are valid. 4282 // 4283 // TODO: properly differentiate simultaneous notify+interrupt. 4284 // In that case, we should propagate the notify to another waiter. 4285 4286 while (_Event < 0) { 4287 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4288 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4289 pthread_cond_destroy(_cond); 4290 pthread_cond_init(_cond, NULL); 4291 } 4292 assert_status(status == 0 || status == EINTR || 4293 status == ETIMEDOUT, 4294 status, "cond_timedwait"); 4295 if (!FilterSpuriousWakeups) break; // previous semantics 4296 if (status == ETIMEDOUT) break; 4297 // We consume and ignore EINTR and spurious wakeups. 4298 } 4299 --_nParked; 4300 if (_Event >= 0) { 4301 ret = OS_OK; 4302 } 4303 _Event = 0; 4304 status = pthread_mutex_unlock(_mutex); 4305 assert_status(status == 0, status, "mutex_unlock"); 4306 assert(_nParked == 0, "invariant"); 4307 // Paranoia to ensure our locked and lock-free paths interact 4308 // correctly with each other. 4309 OrderAccess::fence(); 4310 return ret; 4311} 4312 4313void os::PlatformEvent::unpark() { 4314 // Transitions for _Event: 4315 // 0 => 1 : just return 4316 // 1 => 1 : just return 4317 // -1 => either 0 or 1; must signal target thread 4318 // That is, we can safely transition _Event from -1 to either 4319 // 0 or 1. 4320 // See also: "Semaphores in Plan 9" by Mullender & Cox 4321 // 4322 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4323 // that it will take two back-to-back park() calls for the owning 4324 // thread to block. This has the benefit of forcing a spurious return 4325 // from the first park() call after an unpark() call which will help 4326 // shake out uses of park() and unpark() without condition variables. 4327 4328 if (Atomic::xchg(1, &_Event) >= 0) return; 4329 4330 // Wait for the thread associated with the event to vacate 4331 int status = pthread_mutex_lock(_mutex); 4332 assert_status(status == 0, status, "mutex_lock"); 4333 int AnyWaiters = _nParked; 4334 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4335 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4336 AnyWaiters = 0; 4337 pthread_cond_signal(_cond); 4338 } 4339 status = pthread_mutex_unlock(_mutex); 4340 assert_status(status == 0, status, "mutex_unlock"); 4341 if (AnyWaiters != 0) { 4342 // Note that we signal() *after* dropping the lock for "immortal" Events. 4343 // This is safe and avoids a common class of futile wakeups. In rare 4344 // circumstances this can cause a thread to return prematurely from 4345 // cond_{timed}wait() but the spurious wakeup is benign and the victim 4346 // will simply re-test the condition and re-park itself. 4347 // This provides particular benefit if the underlying platform does not 4348 // provide wait morphing. 4349 status = pthread_cond_signal(_cond); 4350 assert_status(status == 0, status, "cond_signal"); 4351 } 4352} 4353 4354 4355// JSR166 4356// ------------------------------------------------------- 4357 4358// The solaris and bsd implementations of park/unpark are fairly 4359// conservative for now, but can be improved. They currently use a 4360// mutex/condvar pair, plus a a count. 4361// Park decrements count if > 0, else does a condvar wait. Unpark 4362// sets count to 1 and signals condvar. Only one thread ever waits 4363// on the condvar. Contention seen when trying to park implies that someone 4364// is unparking you, so don't wait. And spurious returns are fine, so there 4365// is no need to track notifications. 4366 4367#define MAX_SECS 100000000 4368 4369// This code is common to bsd and solaris and will be moved to a 4370// common place in dolphin. 4371// 4372// The passed in time value is either a relative time in nanoseconds 4373// or an absolute time in milliseconds. Either way it has to be unpacked 4374// into suitable seconds and nanoseconds components and stored in the 4375// given timespec structure. 4376// Given time is a 64-bit value and the time_t used in the timespec is only 4377// a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4378// overflow if times way in the future are given. Further on Solaris versions 4379// prior to 10 there is a restriction (see cond_timedwait) that the specified 4380// number of seconds, in abstime, is less than current_time + 100,000,000. 4381// As it will be 28 years before "now + 100000000" will overflow we can 4382// ignore overflow and just impose a hard-limit on seconds using the value 4383// of "now + 100,000,000". This places a limit on the timeout of about 3.17 4384// years from "now". 4385 4386static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4387 assert(time > 0, "convertTime"); 4388 4389 struct timeval now; 4390 int status = gettimeofday(&now, NULL); 4391 assert(status == 0, "gettimeofday"); 4392 4393 time_t max_secs = now.tv_sec + MAX_SECS; 4394 4395 if (isAbsolute) { 4396 jlong secs = time / 1000; 4397 if (secs > max_secs) { 4398 absTime->tv_sec = max_secs; 4399 } else { 4400 absTime->tv_sec = secs; 4401 } 4402 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4403 } else { 4404 jlong secs = time / NANOSECS_PER_SEC; 4405 if (secs >= MAX_SECS) { 4406 absTime->tv_sec = max_secs; 4407 absTime->tv_nsec = 0; 4408 } else { 4409 absTime->tv_sec = now.tv_sec + secs; 4410 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4411 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4412 absTime->tv_nsec -= NANOSECS_PER_SEC; 4413 ++absTime->tv_sec; // note: this must be <= max_secs 4414 } 4415 } 4416 } 4417 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4418 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4419 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4420 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4421} 4422 4423void Parker::park(bool isAbsolute, jlong time) { 4424 // Ideally we'd do something useful while spinning, such 4425 // as calling unpackTime(). 4426 4427 // Optional fast-path check: 4428 // Return immediately if a permit is available. 4429 // We depend on Atomic::xchg() having full barrier semantics 4430 // since we are doing a lock-free update to _counter. 4431 if (Atomic::xchg(0, &_counter) > 0) return; 4432 4433 Thread* thread = Thread::current(); 4434 assert(thread->is_Java_thread(), "Must be JavaThread"); 4435 JavaThread *jt = (JavaThread *)thread; 4436 4437 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4438 // Check interrupt before trying to wait 4439 if (Thread::is_interrupted(thread, false)) { 4440 return; 4441 } 4442 4443 // Next, demultiplex/decode time arguments 4444 struct timespec absTime; 4445 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4446 return; 4447 } 4448 if (time > 0) { 4449 unpackTime(&absTime, isAbsolute, time); 4450 } 4451 4452 4453 // Enter safepoint region 4454 // Beware of deadlocks such as 6317397. 4455 // The per-thread Parker:: mutex is a classic leaf-lock. 4456 // In particular a thread must never block on the Threads_lock while 4457 // holding the Parker:: mutex. If safepoints are pending both the 4458 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4459 ThreadBlockInVM tbivm(jt); 4460 4461 // Don't wait if cannot get lock since interference arises from 4462 // unblocking. Also. check interrupt before trying wait 4463 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4464 return; 4465 } 4466 4467 int status; 4468 if (_counter > 0) { // no wait needed 4469 _counter = 0; 4470 status = pthread_mutex_unlock(_mutex); 4471 assert(status == 0, "invariant"); 4472 // Paranoia to ensure our locked and lock-free paths interact 4473 // correctly with each other and Java-level accesses. 4474 OrderAccess::fence(); 4475 return; 4476 } 4477 4478#ifdef ASSERT 4479 // Don't catch signals while blocked; let the running threads have the signals. 4480 // (This allows a debugger to break into the running thread.) 4481 sigset_t oldsigs; 4482 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4483 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4484#endif 4485 4486 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4487 jt->set_suspend_equivalent(); 4488 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4489 4490 if (time == 0) { 4491 status = pthread_cond_wait(_cond, _mutex); 4492 } else { 4493 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &absTime); 4494 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4495 pthread_cond_destroy(_cond); 4496 pthread_cond_init(_cond, NULL); 4497 } 4498 } 4499 assert_status(status == 0 || status == EINTR || 4500 status == ETIMEDOUT, 4501 status, "cond_timedwait"); 4502 4503#ifdef ASSERT 4504 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4505#endif 4506 4507 _counter = 0; 4508 status = pthread_mutex_unlock(_mutex); 4509 assert_status(status == 0, status, "invariant"); 4510 // Paranoia to ensure our locked and lock-free paths interact 4511 // correctly with each other and Java-level accesses. 4512 OrderAccess::fence(); 4513 4514 // If externally suspended while waiting, re-suspend 4515 if (jt->handle_special_suspend_equivalent_condition()) { 4516 jt->java_suspend_self(); 4517 } 4518} 4519 4520void Parker::unpark() { 4521 int status = pthread_mutex_lock(_mutex); 4522 assert(status == 0, "invariant"); 4523 const int s = _counter; 4524 _counter = 1; 4525 if (s < 1) { 4526 if (WorkAroundNPTLTimedWaitHang) { 4527 status = pthread_cond_signal(_cond); 4528 assert(status == 0, "invariant"); 4529 status = pthread_mutex_unlock(_mutex); 4530 assert(status == 0, "invariant"); 4531 } else { 4532 status = pthread_mutex_unlock(_mutex); 4533 assert(status == 0, "invariant"); 4534 status = pthread_cond_signal(_cond); 4535 assert(status == 0, "invariant"); 4536 } 4537 } else { 4538 pthread_mutex_unlock(_mutex); 4539 assert(status == 0, "invariant"); 4540 } 4541} 4542 4543 4544// Darwin has no "environ" in a dynamic library. 4545#ifdef __APPLE__ 4546 #include <crt_externs.h> 4547 #define environ (*_NSGetEnviron()) 4548#else 4549extern char** environ; 4550#endif 4551 4552// Run the specified command in a separate process. Return its exit value, 4553// or -1 on failure (e.g. can't fork a new process). 4554// Unlike system(), this function can be called from signal handler. It 4555// doesn't block SIGINT et al. 4556int os::fork_and_exec(char* cmd) { 4557 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4558 4559 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4560 // pthread_atfork handlers and reset pthread library. All we need is a 4561 // separate process to execve. Make a direct syscall to fork process. 4562 // On IA64 there's no fork syscall, we have to use fork() and hope for 4563 // the best... 4564 pid_t pid = fork(); 4565 4566 if (pid < 0) { 4567 // fork failed 4568 return -1; 4569 4570 } else if (pid == 0) { 4571 // child process 4572 4573 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4574 // first to kill every thread on the thread list. Because this list is 4575 // not reset by fork() (see notes above), execve() will instead kill 4576 // every thread in the parent process. We know this is the only thread 4577 // in the new process, so make a system call directly. 4578 // IA64 should use normal execve() from glibc to match the glibc fork() 4579 // above. 4580 execve("/bin/sh", (char* const*)argv, environ); 4581 4582 // execve failed 4583 _exit(-1); 4584 4585 } else { 4586 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4587 // care about the actual exit code, for now. 4588 4589 int status; 4590 4591 // Wait for the child process to exit. This returns immediately if 4592 // the child has already exited. */ 4593 while (waitpid(pid, &status, 0) < 0) { 4594 switch (errno) { 4595 case ECHILD: return 0; 4596 case EINTR: break; 4597 default: return -1; 4598 } 4599 } 4600 4601 if (WIFEXITED(status)) { 4602 // The child exited normally; get its exit code. 4603 return WEXITSTATUS(status); 4604 } else if (WIFSIGNALED(status)) { 4605 // The child exited because of a signal 4606 // The best value to return is 0x80 + signal number, 4607 // because that is what all Unix shells do, and because 4608 // it allows callers to distinguish between process exit and 4609 // process death by signal. 4610 return 0x80 + WTERMSIG(status); 4611 } else { 4612 // Unknown exit code; pass it through 4613 return status; 4614 } 4615 } 4616} 4617 4618// is_headless_jre() 4619// 4620// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4621// in order to report if we are running in a headless jre 4622// 4623// Since JDK8 xawt/libmawt.so was moved into the same directory 4624// as libawt.so, and renamed libawt_xawt.so 4625// 4626bool os::is_headless_jre() { 4627#ifdef __APPLE__ 4628 // We no longer build headless-only on Mac OS X 4629 return false; 4630#else 4631 struct stat statbuf; 4632 char buf[MAXPATHLEN]; 4633 char libmawtpath[MAXPATHLEN]; 4634 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4635 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4636 char *p; 4637 4638 // Get path to libjvm.so 4639 os::jvm_path(buf, sizeof(buf)); 4640 4641 // Get rid of libjvm.so 4642 p = strrchr(buf, '/'); 4643 if (p == NULL) { 4644 return false; 4645 } else { 4646 *p = '\0'; 4647 } 4648 4649 // Get rid of client or server 4650 p = strrchr(buf, '/'); 4651 if (p == NULL) { 4652 return false; 4653 } else { 4654 *p = '\0'; 4655 } 4656 4657 // check xawt/libmawt.so 4658 strcpy(libmawtpath, buf); 4659 strcat(libmawtpath, xawtstr); 4660 if (::stat(libmawtpath, &statbuf) == 0) return false; 4661 4662 // check libawt_xawt.so 4663 strcpy(libmawtpath, buf); 4664 strcat(libmawtpath, new_xawtstr); 4665 if (::stat(libmawtpath, &statbuf) == 0) return false; 4666 4667 return true; 4668#endif 4669} 4670 4671// Get the default path to the core file 4672// Returns the length of the string 4673int os::get_core_path(char* buffer, size_t bufferSize) { 4674 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 4675 4676 // Truncate if theoretical string was longer than bufferSize 4677 n = MIN2(n, (int)bufferSize); 4678 4679 return n; 4680} 4681 4682#ifndef PRODUCT 4683void TestReserveMemorySpecial_test() { 4684 // No tests available for this platform 4685} 4686#endif 4687