os_bsd.cpp revision 6019:28f281e8de1d
1/* 2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25// no precompiled headers 26#include "classfile/classLoader.hpp" 27#include "classfile/systemDictionary.hpp" 28#include "classfile/vmSymbols.hpp" 29#include "code/icBuffer.hpp" 30#include "code/vtableStubs.hpp" 31#include "compiler/compileBroker.hpp" 32#include "compiler/disassembler.hpp" 33#include "interpreter/interpreter.hpp" 34#include "jvm_bsd.h" 35#include "memory/allocation.inline.hpp" 36#include "memory/filemap.hpp" 37#include "mutex_bsd.inline.hpp" 38#include "oops/oop.inline.hpp" 39#include "os_share_bsd.hpp" 40#include "prims/jniFastGetField.hpp" 41#include "prims/jvm.h" 42#include "prims/jvm_misc.hpp" 43#include "runtime/arguments.hpp" 44#include "runtime/extendedPC.hpp" 45#include "runtime/globals.hpp" 46#include "runtime/interfaceSupport.hpp" 47#include "runtime/java.hpp" 48#include "runtime/javaCalls.hpp" 49#include "runtime/mutexLocker.hpp" 50#include "runtime/objectMonitor.hpp" 51#include "runtime/osThread.hpp" 52#include "runtime/perfMemory.hpp" 53#include "runtime/sharedRuntime.hpp" 54#include "runtime/statSampler.hpp" 55#include "runtime/stubRoutines.hpp" 56#include "runtime/thread.inline.hpp" 57#include "runtime/threadCritical.hpp" 58#include "runtime/timer.hpp" 59#include "services/attachListener.hpp" 60#include "services/memTracker.hpp" 61#include "services/runtimeService.hpp" 62#include "utilities/decoder.hpp" 63#include "utilities/defaultStream.hpp" 64#include "utilities/events.hpp" 65#include "utilities/growableArray.hpp" 66#include "utilities/vmError.hpp" 67 68// put OS-includes here 69# include <sys/types.h> 70# include <sys/mman.h> 71# include <sys/stat.h> 72# include <sys/select.h> 73# include <pthread.h> 74# include <signal.h> 75# include <errno.h> 76# include <dlfcn.h> 77# include <stdio.h> 78# include <unistd.h> 79# include <sys/resource.h> 80# include <pthread.h> 81# include <sys/stat.h> 82# include <sys/time.h> 83# include <sys/times.h> 84# include <sys/utsname.h> 85# include <sys/socket.h> 86# include <sys/wait.h> 87# include <time.h> 88# include <pwd.h> 89# include <poll.h> 90# include <semaphore.h> 91# include <fcntl.h> 92# include <string.h> 93# include <sys/param.h> 94# include <sys/sysctl.h> 95# include <sys/ipc.h> 96# include <sys/shm.h> 97#ifndef __APPLE__ 98# include <link.h> 99#endif 100# include <stdint.h> 101# include <inttypes.h> 102# include <sys/ioctl.h> 103# include <sys/syscall.h> 104 105#if defined(__FreeBSD__) || defined(__NetBSD__) 106# include <elf.h> 107#endif 108 109#ifdef __APPLE__ 110# include <mach/mach.h> // semaphore_* API 111# include <mach-o/dyld.h> 112# include <sys/proc_info.h> 113# include <objc/objc-auto.h> 114#endif 115 116#ifndef MAP_ANONYMOUS 117#define MAP_ANONYMOUS MAP_ANON 118#endif 119 120#define MAX_PATH (2 * K) 121 122// for timer info max values which include all bits 123#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 124 125#define LARGEPAGES_BIT (1 << 6) 126//////////////////////////////////////////////////////////////////////////////// 127// global variables 128julong os::Bsd::_physical_memory = 0; 129 130 131int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 132pthread_t os::Bsd::_main_thread; 133int os::Bsd::_page_size = -1; 134 135static jlong initial_time_count=0; 136 137static int clock_tics_per_sec = 100; 138 139// For diagnostics to print a message once. see run_periodic_checks 140static sigset_t check_signal_done; 141static bool check_signals = true; 142 143static pid_t _initial_pid = 0; 144 145/* Signal number used to suspend/resume a thread */ 146 147/* do not use any signal number less than SIGSEGV, see 4355769 */ 148static int SR_signum = SIGUSR2; 149sigset_t SR_sigset; 150 151 152//////////////////////////////////////////////////////////////////////////////// 153// utility functions 154 155static int SR_initialize(); 156static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 157 158julong os::available_memory() { 159 return Bsd::available_memory(); 160} 161 162// available here means free 163julong os::Bsd::available_memory() { 164 uint64_t available = physical_memory() >> 2; 165#ifdef __APPLE__ 166 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 167 vm_statistics64_data_t vmstat; 168 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 169 (host_info64_t)&vmstat, &count); 170 assert(kerr == KERN_SUCCESS, 171 "host_statistics64 failed - check mach_host_self() and count"); 172 if (kerr == KERN_SUCCESS) { 173 available = vmstat.free_count * os::vm_page_size(); 174 } 175#endif 176 return available; 177} 178 179julong os::physical_memory() { 180 return Bsd::physical_memory(); 181} 182 183//////////////////////////////////////////////////////////////////////////////// 184// environment support 185 186bool os::getenv(const char* name, char* buf, int len) { 187 const char* val = ::getenv(name); 188 if (val != NULL && strlen(val) < (size_t)len) { 189 strcpy(buf, val); 190 return true; 191 } 192 if (len > 0) buf[0] = 0; // return a null string 193 return false; 194} 195 196 197// Return true if user is running as root. 198 199bool os::have_special_privileges() { 200 static bool init = false; 201 static bool privileges = false; 202 if (!init) { 203 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 204 init = true; 205 } 206 return privileges; 207} 208 209 210 211// Cpu architecture string 212#if defined(ZERO) 213static char cpu_arch[] = ZERO_LIBARCH; 214#elif defined(IA64) 215static char cpu_arch[] = "ia64"; 216#elif defined(IA32) 217static char cpu_arch[] = "i386"; 218#elif defined(AMD64) 219static char cpu_arch[] = "amd64"; 220#elif defined(ARM) 221static char cpu_arch[] = "arm"; 222#elif defined(PPC32) 223static char cpu_arch[] = "ppc"; 224#elif defined(SPARC) 225# ifdef _LP64 226static char cpu_arch[] = "sparcv9"; 227# else 228static char cpu_arch[] = "sparc"; 229# endif 230#else 231#error Add appropriate cpu_arch setting 232#endif 233 234// Compiler variant 235#ifdef COMPILER2 236#define COMPILER_VARIANT "server" 237#else 238#define COMPILER_VARIANT "client" 239#endif 240 241 242void os::Bsd::initialize_system_info() { 243 int mib[2]; 244 size_t len; 245 int cpu_val; 246 julong mem_val; 247 248 /* get processors count via hw.ncpus sysctl */ 249 mib[0] = CTL_HW; 250 mib[1] = HW_NCPU; 251 len = sizeof(cpu_val); 252 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 253 assert(len == sizeof(cpu_val), "unexpected data size"); 254 set_processor_count(cpu_val); 255 } 256 else { 257 set_processor_count(1); // fallback 258 } 259 260 /* get physical memory via hw.memsize sysctl (hw.memsize is used 261 * since it returns a 64 bit value) 262 */ 263 mib[0] = CTL_HW; 264 265#if defined (HW_MEMSIZE) // Apple 266 mib[1] = HW_MEMSIZE; 267#elif defined(HW_PHYSMEM) // Most of BSD 268 mib[1] = HW_PHYSMEM; 269#elif defined(HW_REALMEM) // Old FreeBSD 270 mib[1] = HW_REALMEM; 271#else 272 #error No ways to get physmem 273#endif 274 275 len = sizeof(mem_val); 276 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 277 assert(len == sizeof(mem_val), "unexpected data size"); 278 _physical_memory = mem_val; 279 } else { 280 _physical_memory = 256*1024*1024; // fallback (XXXBSD?) 281 } 282 283#ifdef __OpenBSD__ 284 { 285 // limit _physical_memory memory view on OpenBSD since 286 // datasize rlimit restricts us anyway. 287 struct rlimit limits; 288 getrlimit(RLIMIT_DATA, &limits); 289 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 290 } 291#endif 292} 293 294#ifdef __APPLE__ 295static const char *get_home() { 296 const char *home_dir = ::getenv("HOME"); 297 if ((home_dir == NULL) || (*home_dir == '\0')) { 298 struct passwd *passwd_info = getpwuid(geteuid()); 299 if (passwd_info != NULL) { 300 home_dir = passwd_info->pw_dir; 301 } 302 } 303 304 return home_dir; 305} 306#endif 307 308void os::init_system_properties_values() { 309// char arch[12]; 310// sysinfo(SI_ARCHITECTURE, arch, sizeof(arch)); 311 312 // The next steps are taken in the product version: 313 // 314 // Obtain the JAVA_HOME value from the location of libjvm.so. 315 // This library should be located at: 316 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 317 // 318 // If "/jre/lib/" appears at the right place in the path, then we 319 // assume libjvm.so is installed in a JDK and we use this path. 320 // 321 // Otherwise exit with message: "Could not create the Java virtual machine." 322 // 323 // The following extra steps are taken in the debugging version: 324 // 325 // If "/jre/lib/" does NOT appear at the right place in the path 326 // instead of exit check for $JAVA_HOME environment variable. 327 // 328 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 329 // then we append a fake suffix "hotspot/libjvm.so" to this path so 330 // it looks like libjvm.so is installed there 331 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 332 // 333 // Otherwise exit. 334 // 335 // Important note: if the location of libjvm.so changes this 336 // code needs to be changed accordingly. 337 338 // The next few definitions allow the code to be verbatim: 339#define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal) 340#define getenv(n) ::getenv(n) 341 342/* 343 * See ld(1): 344 * The linker uses the following search paths to locate required 345 * shared libraries: 346 * 1: ... 347 * ... 348 * 7: The default directories, normally /lib and /usr/lib. 349 */ 350#ifndef DEFAULT_LIBPATH 351#define DEFAULT_LIBPATH "/lib:/usr/lib" 352#endif 353 354#define EXTENSIONS_DIR "/lib/ext" 355#define ENDORSED_DIR "/lib/endorsed" 356#define REG_DIR "/usr/java/packages" 357 358#ifdef __APPLE__ 359#define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 360#define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 361 const char *user_home_dir = get_home(); 362 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir 363 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 364 sizeof(SYS_EXTENSIONS_DIRS); 365#endif 366 367 { 368 /* sysclasspath, java_home, dll_dir */ 369 { 370 char *home_path; 371 char *dll_path; 372 char *pslash; 373 char buf[MAXPATHLEN]; 374 os::jvm_path(buf, sizeof(buf)); 375 376 // Found the full path to libjvm.so. 377 // Now cut the path to <java_home>/jre if we can. 378 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */ 379 pslash = strrchr(buf, '/'); 380 if (pslash != NULL) 381 *pslash = '\0'; /* get rid of /{client|server|hotspot} */ 382 dll_path = malloc(strlen(buf) + 1); 383 if (dll_path == NULL) 384 return; 385 strcpy(dll_path, buf); 386 Arguments::set_dll_dir(dll_path); 387 388 if (pslash != NULL) { 389 pslash = strrchr(buf, '/'); 390 if (pslash != NULL) { 391 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */ 392#ifndef __APPLE__ 393 pslash = strrchr(buf, '/'); 394 if (pslash != NULL) 395 *pslash = '\0'; /* get rid of /lib */ 396#endif 397 } 398 } 399 400 home_path = malloc(strlen(buf) + 1); 401 if (home_path == NULL) 402 return; 403 strcpy(home_path, buf); 404 Arguments::set_java_home(home_path); 405 406 if (!set_boot_path('/', ':')) 407 return; 408 } 409 410 /* 411 * Where to look for native libraries 412 * 413 * Note: Due to a legacy implementation, most of the library path 414 * is set in the launcher. This was to accomodate linking restrictions 415 * on legacy Bsd implementations (which are no longer supported). 416 * Eventually, all the library path setting will be done here. 417 * 418 * However, to prevent the proliferation of improperly built native 419 * libraries, the new path component /usr/java/packages is added here. 420 * Eventually, all the library path setting will be done here. 421 */ 422 { 423 char *ld_library_path; 424 425 /* 426 * Construct the invariant part of ld_library_path. Note that the 427 * space for the colon and the trailing null are provided by the 428 * nulls included by the sizeof operator (so actually we allocate 429 * a byte more than necessary). 430 */ 431#ifdef __APPLE__ 432 ld_library_path = (char *) malloc(system_ext_size); 433 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir); 434#else 435 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") + 436 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH)); 437 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch); 438#endif 439 440 /* 441 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It 442 * should always exist (until the legacy problem cited above is 443 * addressed). 444 */ 445#ifdef __APPLE__ 446 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper 447 char *l = getenv("JAVA_LIBRARY_PATH"); 448 if (l != NULL) { 449 char *t = ld_library_path; 450 /* That's +1 for the colon and +1 for the trailing '\0' */ 451 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1); 452 sprintf(ld_library_path, "%s:%s", l, t); 453 free(t); 454 } 455 456 char *v = getenv("DYLD_LIBRARY_PATH"); 457#else 458 char *v = getenv("LD_LIBRARY_PATH"); 459#endif 460 if (v != NULL) { 461 char *t = ld_library_path; 462 /* That's +1 for the colon and +1 for the trailing '\0' */ 463 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1); 464 sprintf(ld_library_path, "%s:%s", v, t); 465 free(t); 466 } 467 468#ifdef __APPLE__ 469 // Apple's Java6 has "." at the beginning of java.library.path. 470 // OpenJDK on Windows has "." at the end of java.library.path. 471 // OpenJDK on Linux and Solaris don't have "." in java.library.path 472 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 473 // "." is appended to the end of java.library.path. Yes, this 474 // could cause a change in behavior, but Apple's Java6 behavior 475 // can be achieved by putting "." at the beginning of the 476 // JAVA_LIBRARY_PATH environment variable. 477 { 478 char *t = ld_library_path; 479 // that's +3 for appending ":." and the trailing '\0' 480 ld_library_path = (char *) malloc(strlen(t) + 3); 481 sprintf(ld_library_path, "%s:%s", t, "."); 482 free(t); 483 } 484#endif 485 486 Arguments::set_library_path(ld_library_path); 487 } 488 489 /* 490 * Extensions directories. 491 * 492 * Note that the space for the colon and the trailing null are provided 493 * by the nulls included by the sizeof operator (so actually one byte more 494 * than necessary is allocated). 495 */ 496 { 497#ifdef __APPLE__ 498 char *buf = malloc(strlen(Arguments::get_java_home()) + 499 sizeof(EXTENSIONS_DIR) + system_ext_size); 500 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" 501 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home()); 502#else 503 char *buf = malloc(strlen(Arguments::get_java_home()) + 504 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR)); 505 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR, 506 Arguments::get_java_home()); 507#endif 508 509 Arguments::set_ext_dirs(buf); 510 } 511 512 /* Endorsed standards default directory. */ 513 { 514 char * buf; 515 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR)); 516 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 517 Arguments::set_endorsed_dirs(buf); 518 } 519 } 520 521#ifdef __APPLE__ 522#undef SYS_EXTENSIONS_DIR 523#endif 524#undef malloc 525#undef getenv 526#undef EXTENSIONS_DIR 527#undef ENDORSED_DIR 528 529 // Done 530 return; 531} 532 533//////////////////////////////////////////////////////////////////////////////// 534// breakpoint support 535 536void os::breakpoint() { 537 BREAKPOINT; 538} 539 540extern "C" void breakpoint() { 541 // use debugger to set breakpoint here 542} 543 544//////////////////////////////////////////////////////////////////////////////// 545// signal support 546 547debug_only(static bool signal_sets_initialized = false); 548static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 549 550bool os::Bsd::is_sig_ignored(int sig) { 551 struct sigaction oact; 552 sigaction(sig, (struct sigaction*)NULL, &oact); 553 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 554 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 555 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 556 return true; 557 else 558 return false; 559} 560 561void os::Bsd::signal_sets_init() { 562 // Should also have an assertion stating we are still single-threaded. 563 assert(!signal_sets_initialized, "Already initialized"); 564 // Fill in signals that are necessarily unblocked for all threads in 565 // the VM. Currently, we unblock the following signals: 566 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 567 // by -Xrs (=ReduceSignalUsage)); 568 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 569 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 570 // the dispositions or masks wrt these signals. 571 // Programs embedding the VM that want to use the above signals for their 572 // own purposes must, at this time, use the "-Xrs" option to prevent 573 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 574 // (See bug 4345157, and other related bugs). 575 // In reality, though, unblocking these signals is really a nop, since 576 // these signals are not blocked by default. 577 sigemptyset(&unblocked_sigs); 578 sigemptyset(&allowdebug_blocked_sigs); 579 sigaddset(&unblocked_sigs, SIGILL); 580 sigaddset(&unblocked_sigs, SIGSEGV); 581 sigaddset(&unblocked_sigs, SIGBUS); 582 sigaddset(&unblocked_sigs, SIGFPE); 583 sigaddset(&unblocked_sigs, SR_signum); 584 585 if (!ReduceSignalUsage) { 586 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 587 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 588 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 589 } 590 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 591 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 592 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 593 } 594 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 595 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 596 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 597 } 598 } 599 // Fill in signals that are blocked by all but the VM thread. 600 sigemptyset(&vm_sigs); 601 if (!ReduceSignalUsage) 602 sigaddset(&vm_sigs, BREAK_SIGNAL); 603 debug_only(signal_sets_initialized = true); 604 605} 606 607// These are signals that are unblocked while a thread is running Java. 608// (For some reason, they get blocked by default.) 609sigset_t* os::Bsd::unblocked_signals() { 610 assert(signal_sets_initialized, "Not initialized"); 611 return &unblocked_sigs; 612} 613 614// These are the signals that are blocked while a (non-VM) thread is 615// running Java. Only the VM thread handles these signals. 616sigset_t* os::Bsd::vm_signals() { 617 assert(signal_sets_initialized, "Not initialized"); 618 return &vm_sigs; 619} 620 621// These are signals that are blocked during cond_wait to allow debugger in 622sigset_t* os::Bsd::allowdebug_blocked_signals() { 623 assert(signal_sets_initialized, "Not initialized"); 624 return &allowdebug_blocked_sigs; 625} 626 627void os::Bsd::hotspot_sigmask(Thread* thread) { 628 629 //Save caller's signal mask before setting VM signal mask 630 sigset_t caller_sigmask; 631 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 632 633 OSThread* osthread = thread->osthread(); 634 osthread->set_caller_sigmask(caller_sigmask); 635 636 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 637 638 if (!ReduceSignalUsage) { 639 if (thread->is_VM_thread()) { 640 // Only the VM thread handles BREAK_SIGNAL ... 641 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 642 } else { 643 // ... all other threads block BREAK_SIGNAL 644 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 645 } 646 } 647} 648 649 650////////////////////////////////////////////////////////////////////////////// 651// create new thread 652 653// check if it's safe to start a new thread 654static bool _thread_safety_check(Thread* thread) { 655 return true; 656} 657 658#ifdef __APPLE__ 659// library handle for calling objc_registerThreadWithCollector() 660// without static linking to the libobjc library 661#define OBJC_LIB "/usr/lib/libobjc.dylib" 662#define OBJC_GCREGISTER "objc_registerThreadWithCollector" 663typedef void (*objc_registerThreadWithCollector_t)(); 664extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 665objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 666#endif 667 668#ifdef __APPLE__ 669static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 670 // Additional thread_id used to correlate threads in SA 671 thread_identifier_info_data_t m_ident_info; 672 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 673 674 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 675 (thread_info_t) &m_ident_info, &count); 676 677 return m_ident_info.thread_id; 678} 679#endif 680 681// Thread start routine for all newly created threads 682static void *java_start(Thread *thread) { 683 // Try to randomize the cache line index of hot stack frames. 684 // This helps when threads of the same stack traces evict each other's 685 // cache lines. The threads can be either from the same JVM instance, or 686 // from different JVM instances. The benefit is especially true for 687 // processors with hyperthreading technology. 688 static int counter = 0; 689 int pid = os::current_process_id(); 690 alloca(((pid ^ counter++) & 7) * 128); 691 692 ThreadLocalStorage::set_thread(thread); 693 694 OSThread* osthread = thread->osthread(); 695 Monitor* sync = osthread->startThread_lock(); 696 697 // non floating stack BsdThreads needs extra check, see above 698 if (!_thread_safety_check(thread)) { 699 // notify parent thread 700 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 701 osthread->set_state(ZOMBIE); 702 sync->notify_all(); 703 return NULL; 704 } 705 706 osthread->set_thread_id(os::Bsd::gettid()); 707 708#ifdef __APPLE__ 709 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 710 guarantee(unique_thread_id != 0, "unique thread id was not found"); 711 osthread->set_unique_thread_id(unique_thread_id); 712#endif 713 // initialize signal mask for this thread 714 os::Bsd::hotspot_sigmask(thread); 715 716 // initialize floating point control register 717 os::Bsd::init_thread_fpu_state(); 718 719#ifdef __APPLE__ 720 // register thread with objc gc 721 if (objc_registerThreadWithCollectorFunction != NULL) { 722 objc_registerThreadWithCollectorFunction(); 723 } 724#endif 725 726 // handshaking with parent thread 727 { 728 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 729 730 // notify parent thread 731 osthread->set_state(INITIALIZED); 732 sync->notify_all(); 733 734 // wait until os::start_thread() 735 while (osthread->get_state() == INITIALIZED) { 736 sync->wait(Mutex::_no_safepoint_check_flag); 737 } 738 } 739 740 // call one more level start routine 741 thread->run(); 742 743 return 0; 744} 745 746bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 747 assert(thread->osthread() == NULL, "caller responsible"); 748 749 // Allocate the OSThread object 750 OSThread* osthread = new OSThread(NULL, NULL); 751 if (osthread == NULL) { 752 return false; 753 } 754 755 // set the correct thread state 756 osthread->set_thread_type(thr_type); 757 758 // Initial state is ALLOCATED but not INITIALIZED 759 osthread->set_state(ALLOCATED); 760 761 thread->set_osthread(osthread); 762 763 // init thread attributes 764 pthread_attr_t attr; 765 pthread_attr_init(&attr); 766 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 767 768 // stack size 769 if (os::Bsd::supports_variable_stack_size()) { 770 // calculate stack size if it's not specified by caller 771 if (stack_size == 0) { 772 stack_size = os::Bsd::default_stack_size(thr_type); 773 774 switch (thr_type) { 775 case os::java_thread: 776 // Java threads use ThreadStackSize which default value can be 777 // changed with the flag -Xss 778 assert (JavaThread::stack_size_at_create() > 0, "this should be set"); 779 stack_size = JavaThread::stack_size_at_create(); 780 break; 781 case os::compiler_thread: 782 if (CompilerThreadStackSize > 0) { 783 stack_size = (size_t)(CompilerThreadStackSize * K); 784 break; 785 } // else fall through: 786 // use VMThreadStackSize if CompilerThreadStackSize is not defined 787 case os::vm_thread: 788 case os::pgc_thread: 789 case os::cgc_thread: 790 case os::watcher_thread: 791 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 792 break; 793 } 794 } 795 796 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 797 pthread_attr_setstacksize(&attr, stack_size); 798 } else { 799 // let pthread_create() pick the default value. 800 } 801 802 ThreadState state; 803 804 { 805 pthread_t tid; 806 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 807 808 pthread_attr_destroy(&attr); 809 810 if (ret != 0) { 811 if (PrintMiscellaneous && (Verbose || WizardMode)) { 812 perror("pthread_create()"); 813 } 814 // Need to clean up stuff we've allocated so far 815 thread->set_osthread(NULL); 816 delete osthread; 817 return false; 818 } 819 820 // Store pthread info into the OSThread 821 osthread->set_pthread_id(tid); 822 823 // Wait until child thread is either initialized or aborted 824 { 825 Monitor* sync_with_child = osthread->startThread_lock(); 826 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 827 while ((state = osthread->get_state()) == ALLOCATED) { 828 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 829 } 830 } 831 832 } 833 834 // Aborted due to thread limit being reached 835 if (state == ZOMBIE) { 836 thread->set_osthread(NULL); 837 delete osthread; 838 return false; 839 } 840 841 // The thread is returned suspended (in state INITIALIZED), 842 // and is started higher up in the call chain 843 assert(state == INITIALIZED, "race condition"); 844 return true; 845} 846 847///////////////////////////////////////////////////////////////////////////// 848// attach existing thread 849 850// bootstrap the main thread 851bool os::create_main_thread(JavaThread* thread) { 852 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 853 return create_attached_thread(thread); 854} 855 856bool os::create_attached_thread(JavaThread* thread) { 857#ifdef ASSERT 858 thread->verify_not_published(); 859#endif 860 861 // Allocate the OSThread object 862 OSThread* osthread = new OSThread(NULL, NULL); 863 864 if (osthread == NULL) { 865 return false; 866 } 867 868 osthread->set_thread_id(os::Bsd::gettid()); 869 870 // Store pthread info into the OSThread 871#ifdef __APPLE__ 872 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 873 guarantee(unique_thread_id != 0, "just checking"); 874 osthread->set_unique_thread_id(unique_thread_id); 875#endif 876 osthread->set_pthread_id(::pthread_self()); 877 878 // initialize floating point control register 879 os::Bsd::init_thread_fpu_state(); 880 881 // Initial thread state is RUNNABLE 882 osthread->set_state(RUNNABLE); 883 884 thread->set_osthread(osthread); 885 886 // initialize signal mask for this thread 887 // and save the caller's signal mask 888 os::Bsd::hotspot_sigmask(thread); 889 890 return true; 891} 892 893void os::pd_start_thread(Thread* thread) { 894 OSThread * osthread = thread->osthread(); 895 assert(osthread->get_state() != INITIALIZED, "just checking"); 896 Monitor* sync_with_child = osthread->startThread_lock(); 897 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 898 sync_with_child->notify(); 899} 900 901// Free Bsd resources related to the OSThread 902void os::free_thread(OSThread* osthread) { 903 assert(osthread != NULL, "osthread not set"); 904 905 if (Thread::current()->osthread() == osthread) { 906 // Restore caller's signal mask 907 sigset_t sigmask = osthread->caller_sigmask(); 908 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 909 } 910 911 delete osthread; 912} 913 914////////////////////////////////////////////////////////////////////////////// 915// thread local storage 916 917int os::allocate_thread_local_storage() { 918 pthread_key_t key; 919 int rslt = pthread_key_create(&key, NULL); 920 assert(rslt == 0, "cannot allocate thread local storage"); 921 return (int)key; 922} 923 924// Note: This is currently not used by VM, as we don't destroy TLS key 925// on VM exit. 926void os::free_thread_local_storage(int index) { 927 int rslt = pthread_key_delete((pthread_key_t)index); 928 assert(rslt == 0, "invalid index"); 929} 930 931void os::thread_local_storage_at_put(int index, void* value) { 932 int rslt = pthread_setspecific((pthread_key_t)index, value); 933 assert(rslt == 0, "pthread_setspecific failed"); 934} 935 936extern "C" Thread* get_thread() { 937 return ThreadLocalStorage::thread(); 938} 939 940 941//////////////////////////////////////////////////////////////////////////////// 942// time support 943 944// Time since start-up in seconds to a fine granularity. 945// Used by VMSelfDestructTimer and the MemProfiler. 946double os::elapsedTime() { 947 948 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 949} 950 951jlong os::elapsed_counter() { 952 return javaTimeNanos() - initial_time_count; 953} 954 955jlong os::elapsed_frequency() { 956 return NANOSECS_PER_SEC; // nanosecond resolution 957} 958 959bool os::supports_vtime() { return true; } 960bool os::enable_vtime() { return false; } 961bool os::vtime_enabled() { return false; } 962 963double os::elapsedVTime() { 964 // better than nothing, but not much 965 return elapsedTime(); 966} 967 968jlong os::javaTimeMillis() { 969 timeval time; 970 int status = gettimeofday(&time, NULL); 971 assert(status != -1, "bsd error"); 972 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 973} 974 975#ifndef CLOCK_MONOTONIC 976#define CLOCK_MONOTONIC (1) 977#endif 978 979#ifdef __APPLE__ 980void os::Bsd::clock_init() { 981 // XXXDARWIN: Investigate replacement monotonic clock 982} 983#else 984void os::Bsd::clock_init() { 985 struct timespec res; 986 struct timespec tp; 987 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 988 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 989 // yes, monotonic clock is supported 990 _clock_gettime = ::clock_gettime; 991 } 992} 993#endif 994 995 996jlong os::javaTimeNanos() { 997 if (Bsd::supports_monotonic_clock()) { 998 struct timespec tp; 999 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp); 1000 assert(status == 0, "gettime error"); 1001 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1002 return result; 1003 } else { 1004 timeval time; 1005 int status = gettimeofday(&time, NULL); 1006 assert(status != -1, "bsd error"); 1007 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1008 return 1000 * usecs; 1009 } 1010} 1011 1012void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1013 if (Bsd::supports_monotonic_clock()) { 1014 info_ptr->max_value = ALL_64_BITS; 1015 1016 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1017 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1018 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1019 } else { 1020 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1021 info_ptr->max_value = ALL_64_BITS; 1022 1023 // gettimeofday is a real time clock so it skips 1024 info_ptr->may_skip_backward = true; 1025 info_ptr->may_skip_forward = true; 1026 } 1027 1028 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1029} 1030 1031// Return the real, user, and system times in seconds from an 1032// arbitrary fixed point in the past. 1033bool os::getTimesSecs(double* process_real_time, 1034 double* process_user_time, 1035 double* process_system_time) { 1036 struct tms ticks; 1037 clock_t real_ticks = times(&ticks); 1038 1039 if (real_ticks == (clock_t) (-1)) { 1040 return false; 1041 } else { 1042 double ticks_per_second = (double) clock_tics_per_sec; 1043 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1044 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1045 *process_real_time = ((double) real_ticks) / ticks_per_second; 1046 1047 return true; 1048 } 1049} 1050 1051 1052char * os::local_time_string(char *buf, size_t buflen) { 1053 struct tm t; 1054 time_t long_time; 1055 time(&long_time); 1056 localtime_r(&long_time, &t); 1057 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1058 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1059 t.tm_hour, t.tm_min, t.tm_sec); 1060 return buf; 1061} 1062 1063struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1064 return localtime_r(clock, res); 1065} 1066 1067//////////////////////////////////////////////////////////////////////////////// 1068// runtime exit support 1069 1070// Note: os::shutdown() might be called very early during initialization, or 1071// called from signal handler. Before adding something to os::shutdown(), make 1072// sure it is async-safe and can handle partially initialized VM. 1073void os::shutdown() { 1074 1075 // allow PerfMemory to attempt cleanup of any persistent resources 1076 perfMemory_exit(); 1077 1078 // needs to remove object in file system 1079 AttachListener::abort(); 1080 1081 // flush buffered output, finish log files 1082 ostream_abort(); 1083 1084 // Check for abort hook 1085 abort_hook_t abort_hook = Arguments::abort_hook(); 1086 if (abort_hook != NULL) { 1087 abort_hook(); 1088 } 1089 1090} 1091 1092// Note: os::abort() might be called very early during initialization, or 1093// called from signal handler. Before adding something to os::abort(), make 1094// sure it is async-safe and can handle partially initialized VM. 1095void os::abort(bool dump_core) { 1096 os::shutdown(); 1097 if (dump_core) { 1098#ifndef PRODUCT 1099 fdStream out(defaultStream::output_fd()); 1100 out.print_raw("Current thread is "); 1101 char buf[16]; 1102 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1103 out.print_raw_cr(buf); 1104 out.print_raw_cr("Dumping core ..."); 1105#endif 1106 ::abort(); // dump core 1107 } 1108 1109 ::exit(1); 1110} 1111 1112// Die immediately, no exit hook, no abort hook, no cleanup. 1113void os::die() { 1114 // _exit() on BsdThreads only kills current thread 1115 ::abort(); 1116} 1117 1118// unused on bsd for now. 1119void os::set_error_file(const char *logfile) {} 1120 1121 1122// This method is a copy of JDK's sysGetLastErrorString 1123// from src/solaris/hpi/src/system_md.c 1124 1125size_t os::lasterror(char *buf, size_t len) { 1126 1127 if (errno == 0) return 0; 1128 1129 const char *s = ::strerror(errno); 1130 size_t n = ::strlen(s); 1131 if (n >= len) { 1132 n = len - 1; 1133 } 1134 ::strncpy(buf, s, n); 1135 buf[n] = '\0'; 1136 return n; 1137} 1138 1139// Information of current thread in variety of formats 1140pid_t os::Bsd::gettid() { 1141 int retval = -1; 1142 1143#ifdef __APPLE__ //XNU kernel 1144 // despite the fact mach port is actually not a thread id use it 1145 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1146 retval = ::pthread_mach_thread_np(::pthread_self()); 1147 guarantee(retval != 0, "just checking"); 1148 return retval; 1149 1150#elif __FreeBSD__ 1151 retval = syscall(SYS_thr_self); 1152#elif __OpenBSD__ 1153 retval = syscall(SYS_getthrid); 1154#elif __NetBSD__ 1155 retval = (pid_t) syscall(SYS__lwp_self); 1156#endif 1157 1158 if (retval == -1) { 1159 return getpid(); 1160 } 1161} 1162 1163intx os::current_thread_id() { 1164#ifdef __APPLE__ 1165 return (intx)::pthread_mach_thread_np(::pthread_self()); 1166#else 1167 return (intx)::pthread_self(); 1168#endif 1169} 1170 1171int os::current_process_id() { 1172 1173 // Under the old bsd thread library, bsd gives each thread 1174 // its own process id. Because of this each thread will return 1175 // a different pid if this method were to return the result 1176 // of getpid(2). Bsd provides no api that returns the pid 1177 // of the launcher thread for the vm. This implementation 1178 // returns a unique pid, the pid of the launcher thread 1179 // that starts the vm 'process'. 1180 1181 // Under the NPTL, getpid() returns the same pid as the 1182 // launcher thread rather than a unique pid per thread. 1183 // Use gettid() if you want the old pre NPTL behaviour. 1184 1185 // if you are looking for the result of a call to getpid() that 1186 // returns a unique pid for the calling thread, then look at the 1187 // OSThread::thread_id() method in osThread_bsd.hpp file 1188 1189 return (int)(_initial_pid ? _initial_pid : getpid()); 1190} 1191 1192// DLL functions 1193 1194#define JNI_LIB_PREFIX "lib" 1195#ifdef __APPLE__ 1196#define JNI_LIB_SUFFIX ".dylib" 1197#else 1198#define JNI_LIB_SUFFIX ".so" 1199#endif 1200 1201const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1202 1203// This must be hard coded because it's the system's temporary 1204// directory not the java application's temp directory, ala java.io.tmpdir. 1205#ifdef __APPLE__ 1206// macosx has a secure per-user temporary directory 1207char temp_path_storage[PATH_MAX]; 1208const char* os::get_temp_directory() { 1209 static char *temp_path = NULL; 1210 if (temp_path == NULL) { 1211 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1212 if (pathSize == 0 || pathSize > PATH_MAX) { 1213 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1214 } 1215 temp_path = temp_path_storage; 1216 } 1217 return temp_path; 1218} 1219#else /* __APPLE__ */ 1220const char* os::get_temp_directory() { return "/tmp"; } 1221#endif /* __APPLE__ */ 1222 1223static bool file_exists(const char* filename) { 1224 struct stat statbuf; 1225 if (filename == NULL || strlen(filename) == 0) { 1226 return false; 1227 } 1228 return os::stat(filename, &statbuf) == 0; 1229} 1230 1231bool os::dll_build_name(char* buffer, size_t buflen, 1232 const char* pname, const char* fname) { 1233 bool retval = false; 1234 // Copied from libhpi 1235 const size_t pnamelen = pname ? strlen(pname) : 0; 1236 1237 // Return error on buffer overflow. 1238 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1239 return retval; 1240 } 1241 1242 if (pnamelen == 0) { 1243 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1244 retval = true; 1245 } else if (strchr(pname, *os::path_separator()) != NULL) { 1246 int n; 1247 char** pelements = split_path(pname, &n); 1248 if (pelements == NULL) { 1249 return false; 1250 } 1251 for (int i = 0 ; i < n ; i++) { 1252 // Really shouldn't be NULL, but check can't hurt 1253 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1254 continue; // skip the empty path values 1255 } 1256 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1257 pelements[i], fname); 1258 if (file_exists(buffer)) { 1259 retval = true; 1260 break; 1261 } 1262 } 1263 // release the storage 1264 for (int i = 0 ; i < n ; i++) { 1265 if (pelements[i] != NULL) { 1266 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1267 } 1268 } 1269 if (pelements != NULL) { 1270 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1271 } 1272 } else { 1273 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1274 retval = true; 1275 } 1276 return retval; 1277} 1278 1279// check if addr is inside libjvm.so 1280bool os::address_is_in_vm(address addr) { 1281 static address libjvm_base_addr; 1282 Dl_info dlinfo; 1283 1284 if (libjvm_base_addr == NULL) { 1285 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1286 libjvm_base_addr = (address)dlinfo.dli_fbase; 1287 } 1288 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1289 } 1290 1291 if (dladdr((void *)addr, &dlinfo) != 0) { 1292 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1293 } 1294 1295 return false; 1296} 1297 1298 1299#define MACH_MAXSYMLEN 256 1300 1301bool os::dll_address_to_function_name(address addr, char *buf, 1302 int buflen, int *offset) { 1303 // buf is not optional, but offset is optional 1304 assert(buf != NULL, "sanity check"); 1305 1306 Dl_info dlinfo; 1307 char localbuf[MACH_MAXSYMLEN]; 1308 1309 if (dladdr((void*)addr, &dlinfo) != 0) { 1310 // see if we have a matching symbol 1311 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1312 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1313 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1314 } 1315 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1316 return true; 1317 } 1318 // no matching symbol so try for just file info 1319 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1320 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1321 buf, buflen, offset, dlinfo.dli_fname)) { 1322 return true; 1323 } 1324 } 1325 1326 // Handle non-dynamic manually: 1327 if (dlinfo.dli_fbase != NULL && 1328 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1329 dlinfo.dli_fbase)) { 1330 if (!Decoder::demangle(localbuf, buf, buflen)) { 1331 jio_snprintf(buf, buflen, "%s", localbuf); 1332 } 1333 return true; 1334 } 1335 } 1336 buf[0] = '\0'; 1337 if (offset != NULL) *offset = -1; 1338 return false; 1339} 1340 1341// ported from solaris version 1342bool os::dll_address_to_library_name(address addr, char* buf, 1343 int buflen, int* offset) { 1344 // buf is not optional, but offset is optional 1345 assert(buf != NULL, "sanity check"); 1346 1347 Dl_info dlinfo; 1348 1349 if (dladdr((void*)addr, &dlinfo) != 0) { 1350 if (dlinfo.dli_fname != NULL) { 1351 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1352 } 1353 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1354 *offset = addr - (address)dlinfo.dli_fbase; 1355 } 1356 return true; 1357 } 1358 1359 buf[0] = '\0'; 1360 if (offset) *offset = -1; 1361 return false; 1362} 1363 1364// Loads .dll/.so and 1365// in case of error it checks if .dll/.so was built for the 1366// same architecture as Hotspot is running on 1367 1368#ifdef __APPLE__ 1369void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1370 void * result= ::dlopen(filename, RTLD_LAZY); 1371 if (result != NULL) { 1372 // Successful loading 1373 return result; 1374 } 1375 1376 // Read system error message into ebuf 1377 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1378 ebuf[ebuflen-1]='\0'; 1379 1380 return NULL; 1381} 1382#else 1383void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1384{ 1385 void * result= ::dlopen(filename, RTLD_LAZY); 1386 if (result != NULL) { 1387 // Successful loading 1388 return result; 1389 } 1390 1391 Elf32_Ehdr elf_head; 1392 1393 // Read system error message into ebuf 1394 // It may or may not be overwritten below 1395 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1396 ebuf[ebuflen-1]='\0'; 1397 int diag_msg_max_length=ebuflen-strlen(ebuf); 1398 char* diag_msg_buf=ebuf+strlen(ebuf); 1399 1400 if (diag_msg_max_length==0) { 1401 // No more space in ebuf for additional diagnostics message 1402 return NULL; 1403 } 1404 1405 1406 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1407 1408 if (file_descriptor < 0) { 1409 // Can't open library, report dlerror() message 1410 return NULL; 1411 } 1412 1413 bool failed_to_read_elf_head= 1414 (sizeof(elf_head)!= 1415 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 1416 1417 ::close(file_descriptor); 1418 if (failed_to_read_elf_head) { 1419 // file i/o error - report dlerror() msg 1420 return NULL; 1421 } 1422 1423 typedef struct { 1424 Elf32_Half code; // Actual value as defined in elf.h 1425 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1426 char elf_class; // 32 or 64 bit 1427 char endianess; // MSB or LSB 1428 char* name; // String representation 1429 } arch_t; 1430 1431 #ifndef EM_486 1432 #define EM_486 6 /* Intel 80486 */ 1433 #endif 1434 1435 #ifndef EM_MIPS_RS3_LE 1436 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1437 #endif 1438 1439 #ifndef EM_PPC64 1440 #define EM_PPC64 21 /* PowerPC64 */ 1441 #endif 1442 1443 #ifndef EM_S390 1444 #define EM_S390 22 /* IBM System/390 */ 1445 #endif 1446 1447 #ifndef EM_IA_64 1448 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1449 #endif 1450 1451 #ifndef EM_X86_64 1452 #define EM_X86_64 62 /* AMD x86-64 */ 1453 #endif 1454 1455 static const arch_t arch_array[]={ 1456 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1457 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1458 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1459 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1460 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1461 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1462 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1463 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1464 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1465 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1466 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1467 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1468 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1469 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1470 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1471 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1472 }; 1473 1474 #if (defined IA32) 1475 static Elf32_Half running_arch_code=EM_386; 1476 #elif (defined AMD64) 1477 static Elf32_Half running_arch_code=EM_X86_64; 1478 #elif (defined IA64) 1479 static Elf32_Half running_arch_code=EM_IA_64; 1480 #elif (defined __sparc) && (defined _LP64) 1481 static Elf32_Half running_arch_code=EM_SPARCV9; 1482 #elif (defined __sparc) && (!defined _LP64) 1483 static Elf32_Half running_arch_code=EM_SPARC; 1484 #elif (defined __powerpc64__) 1485 static Elf32_Half running_arch_code=EM_PPC64; 1486 #elif (defined __powerpc__) 1487 static Elf32_Half running_arch_code=EM_PPC; 1488 #elif (defined ARM) 1489 static Elf32_Half running_arch_code=EM_ARM; 1490 #elif (defined S390) 1491 static Elf32_Half running_arch_code=EM_S390; 1492 #elif (defined ALPHA) 1493 static Elf32_Half running_arch_code=EM_ALPHA; 1494 #elif (defined MIPSEL) 1495 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1496 #elif (defined PARISC) 1497 static Elf32_Half running_arch_code=EM_PARISC; 1498 #elif (defined MIPS) 1499 static Elf32_Half running_arch_code=EM_MIPS; 1500 #elif (defined M68K) 1501 static Elf32_Half running_arch_code=EM_68K; 1502 #else 1503 #error Method os::dll_load requires that one of following is defined:\ 1504 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1505 #endif 1506 1507 // Identify compatability class for VM's architecture and library's architecture 1508 // Obtain string descriptions for architectures 1509 1510 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1511 int running_arch_index=-1; 1512 1513 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 1514 if (running_arch_code == arch_array[i].code) { 1515 running_arch_index = i; 1516 } 1517 if (lib_arch.code == arch_array[i].code) { 1518 lib_arch.compat_class = arch_array[i].compat_class; 1519 lib_arch.name = arch_array[i].name; 1520 } 1521 } 1522 1523 assert(running_arch_index != -1, 1524 "Didn't find running architecture code (running_arch_code) in arch_array"); 1525 if (running_arch_index == -1) { 1526 // Even though running architecture detection failed 1527 // we may still continue with reporting dlerror() message 1528 return NULL; 1529 } 1530 1531 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1532 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1533 return NULL; 1534 } 1535 1536#ifndef S390 1537 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1539 return NULL; 1540 } 1541#endif // !S390 1542 1543 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1544 if ( lib_arch.name!=NULL ) { 1545 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1546 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1547 lib_arch.name, arch_array[running_arch_index].name); 1548 } else { 1549 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1550 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1551 lib_arch.code, 1552 arch_array[running_arch_index].name); 1553 } 1554 } 1555 1556 return NULL; 1557} 1558#endif /* !__APPLE__ */ 1559 1560void* os::get_default_process_handle() { 1561#ifdef __APPLE__ 1562 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1563 // to avoid finding unexpected symbols on second (or later) 1564 // loads of a library. 1565 return (void*)::dlopen(NULL, RTLD_FIRST); 1566#else 1567 return (void*)::dlopen(NULL, RTLD_LAZY); 1568#endif 1569} 1570 1571// XXX: Do we need a lock around this as per Linux? 1572void* os::dll_lookup(void* handle, const char* name) { 1573 return dlsym(handle, name); 1574} 1575 1576 1577static bool _print_ascii_file(const char* filename, outputStream* st) { 1578 int fd = ::open(filename, O_RDONLY); 1579 if (fd == -1) { 1580 return false; 1581 } 1582 1583 char buf[32]; 1584 int bytes; 1585 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1586 st->print_raw(buf, bytes); 1587 } 1588 1589 ::close(fd); 1590 1591 return true; 1592} 1593 1594void os::print_dll_info(outputStream *st) { 1595 st->print_cr("Dynamic libraries:"); 1596#ifdef RTLD_DI_LINKMAP 1597 Dl_info dli; 1598 void *handle; 1599 Link_map *map; 1600 Link_map *p; 1601 1602 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1603 dli.dli_fname == NULL) { 1604 st->print_cr("Error: Cannot print dynamic libraries."); 1605 return; 1606 } 1607 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1608 if (handle == NULL) { 1609 st->print_cr("Error: Cannot print dynamic libraries."); 1610 return; 1611 } 1612 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1613 if (map == NULL) { 1614 st->print_cr("Error: Cannot print dynamic libraries."); 1615 return; 1616 } 1617 1618 while (map->l_prev != NULL) 1619 map = map->l_prev; 1620 1621 while (map != NULL) { 1622 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1623 map = map->l_next; 1624 } 1625 1626 dlclose(handle); 1627#elif defined(__APPLE__) 1628 uint32_t count; 1629 uint32_t i; 1630 1631 count = _dyld_image_count(); 1632 for (i = 1; i < count; i++) { 1633 const char *name = _dyld_get_image_name(i); 1634 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 1635 st->print_cr(PTR_FORMAT " \t%s", slide, name); 1636 } 1637#else 1638 st->print_cr("Error: Cannot print dynamic libraries."); 1639#endif 1640} 1641 1642void os::print_os_info_brief(outputStream* st) { 1643 st->print("Bsd"); 1644 1645 os::Posix::print_uname_info(st); 1646} 1647 1648void os::print_os_info(outputStream* st) { 1649 st->print("OS:"); 1650 st->print("Bsd"); 1651 1652 os::Posix::print_uname_info(st); 1653 1654 os::Posix::print_rlimit_info(st); 1655 1656 os::Posix::print_load_average(st); 1657} 1658 1659void os::pd_print_cpu_info(outputStream* st) { 1660 // Nothing to do for now. 1661} 1662 1663void os::print_memory_info(outputStream* st) { 1664 1665 st->print("Memory:"); 1666 st->print(" %dk page", os::vm_page_size()>>10); 1667 1668 st->print(", physical " UINT64_FORMAT "k", 1669 os::physical_memory() >> 10); 1670 st->print("(" UINT64_FORMAT "k free)", 1671 os::available_memory() >> 10); 1672 st->cr(); 1673 1674 // meminfo 1675 st->print("\n/proc/meminfo:\n"); 1676 _print_ascii_file("/proc/meminfo", st); 1677 st->cr(); 1678} 1679 1680void os::print_siginfo(outputStream* st, void* siginfo) { 1681 const siginfo_t* si = (const siginfo_t*)siginfo; 1682 1683 os::Posix::print_siginfo_brief(st, si); 1684 1685 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1686 UseSharedSpaces) { 1687 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1688 if (mapinfo->is_in_shared_space(si->si_addr)) { 1689 st->print("\n\nError accessing class data sharing archive." \ 1690 " Mapped file inaccessible during execution, " \ 1691 " possible disk/network problem."); 1692 } 1693 } 1694 st->cr(); 1695} 1696 1697 1698static void print_signal_handler(outputStream* st, int sig, 1699 char* buf, size_t buflen); 1700 1701void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1702 st->print_cr("Signal Handlers:"); 1703 print_signal_handler(st, SIGSEGV, buf, buflen); 1704 print_signal_handler(st, SIGBUS , buf, buflen); 1705 print_signal_handler(st, SIGFPE , buf, buflen); 1706 print_signal_handler(st, SIGPIPE, buf, buflen); 1707 print_signal_handler(st, SIGXFSZ, buf, buflen); 1708 print_signal_handler(st, SIGILL , buf, buflen); 1709 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1710 print_signal_handler(st, SR_signum, buf, buflen); 1711 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1712 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1713 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1714 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1715} 1716 1717static char saved_jvm_path[MAXPATHLEN] = {0}; 1718 1719// Find the full path to the current module, libjvm 1720void os::jvm_path(char *buf, jint buflen) { 1721 // Error checking. 1722 if (buflen < MAXPATHLEN) { 1723 assert(false, "must use a large-enough buffer"); 1724 buf[0] = '\0'; 1725 return; 1726 } 1727 // Lazy resolve the path to current module. 1728 if (saved_jvm_path[0] != 0) { 1729 strcpy(buf, saved_jvm_path); 1730 return; 1731 } 1732 1733 char dli_fname[MAXPATHLEN]; 1734 bool ret = dll_address_to_library_name( 1735 CAST_FROM_FN_PTR(address, os::jvm_path), 1736 dli_fname, sizeof(dli_fname), NULL); 1737 assert(ret, "cannot locate libjvm"); 1738 char *rp = NULL; 1739 if (ret && dli_fname[0] != '\0') { 1740 rp = realpath(dli_fname, buf); 1741 } 1742 if (rp == NULL) 1743 return; 1744 1745 if (Arguments::sun_java_launcher_is_altjvm()) { 1746 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1747 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1748 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1749 // appears at the right place in the string, then assume we are 1750 // installed in a JDK and we're done. Otherwise, check for a 1751 // JAVA_HOME environment variable and construct a path to the JVM 1752 // being overridden. 1753 1754 const char *p = buf + strlen(buf) - 1; 1755 for (int count = 0; p > buf && count < 5; ++count) { 1756 for (--p; p > buf && *p != '/'; --p) 1757 /* empty */ ; 1758 } 1759 1760 if (strncmp(p, "/jre/lib/", 9) != 0) { 1761 // Look for JAVA_HOME in the environment. 1762 char* java_home_var = ::getenv("JAVA_HOME"); 1763 if (java_home_var != NULL && java_home_var[0] != 0) { 1764 char* jrelib_p; 1765 int len; 1766 1767 // Check the current module name "libjvm" 1768 p = strrchr(buf, '/'); 1769 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1770 1771 rp = realpath(java_home_var, buf); 1772 if (rp == NULL) 1773 return; 1774 1775 // determine if this is a legacy image or modules image 1776 // modules image doesn't have "jre" subdirectory 1777 len = strlen(buf); 1778 jrelib_p = buf + len; 1779 1780 // Add the appropriate library subdir 1781 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1782 if (0 != access(buf, F_OK)) { 1783 snprintf(jrelib_p, buflen-len, "/lib"); 1784 } 1785 1786 // Add the appropriate client or server subdir 1787 len = strlen(buf); 1788 jrelib_p = buf + len; 1789 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1790 if (0 != access(buf, F_OK)) { 1791 snprintf(jrelib_p, buflen-len, "%s", ""); 1792 } 1793 1794 // If the path exists within JAVA_HOME, add the JVM library name 1795 // to complete the path to JVM being overridden. Otherwise fallback 1796 // to the path to the current library. 1797 if (0 == access(buf, F_OK)) { 1798 // Use current module name "libjvm" 1799 len = strlen(buf); 1800 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1801 } else { 1802 // Fall back to path of current library 1803 rp = realpath(dli_fname, buf); 1804 if (rp == NULL) 1805 return; 1806 } 1807 } 1808 } 1809 } 1810 1811 strcpy(saved_jvm_path, buf); 1812} 1813 1814void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1815 // no prefix required, not even "_" 1816} 1817 1818void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1819 // no suffix required 1820} 1821 1822//////////////////////////////////////////////////////////////////////////////// 1823// sun.misc.Signal support 1824 1825static volatile jint sigint_count = 0; 1826 1827static void 1828UserHandler(int sig, void *siginfo, void *context) { 1829 // 4511530 - sem_post is serialized and handled by the manager thread. When 1830 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1831 // don't want to flood the manager thread with sem_post requests. 1832 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1833 return; 1834 1835 // Ctrl-C is pressed during error reporting, likely because the error 1836 // handler fails to abort. Let VM die immediately. 1837 if (sig == SIGINT && is_error_reported()) { 1838 os::die(); 1839 } 1840 1841 os::signal_notify(sig); 1842} 1843 1844void* os::user_handler() { 1845 return CAST_FROM_FN_PTR(void*, UserHandler); 1846} 1847 1848extern "C" { 1849 typedef void (*sa_handler_t)(int); 1850 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1851} 1852 1853void* os::signal(int signal_number, void* handler) { 1854 struct sigaction sigAct, oldSigAct; 1855 1856 sigfillset(&(sigAct.sa_mask)); 1857 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1858 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1859 1860 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1861 // -1 means registration failed 1862 return (void *)-1; 1863 } 1864 1865 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1866} 1867 1868void os::signal_raise(int signal_number) { 1869 ::raise(signal_number); 1870} 1871 1872/* 1873 * The following code is moved from os.cpp for making this 1874 * code platform specific, which it is by its very nature. 1875 */ 1876 1877// Will be modified when max signal is changed to be dynamic 1878int os::sigexitnum_pd() { 1879 return NSIG; 1880} 1881 1882// a counter for each possible signal value 1883static volatile jint pending_signals[NSIG+1] = { 0 }; 1884 1885// Bsd(POSIX) specific hand shaking semaphore. 1886#ifdef __APPLE__ 1887typedef semaphore_t os_semaphore_t; 1888#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1889#define SEM_WAIT(sem) semaphore_wait(sem) 1890#define SEM_POST(sem) semaphore_signal(sem) 1891#define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1892#else 1893typedef sem_t os_semaphore_t; 1894#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1895#define SEM_WAIT(sem) sem_wait(&sem) 1896#define SEM_POST(sem) sem_post(&sem) 1897#define SEM_DESTROY(sem) sem_destroy(&sem) 1898#endif 1899 1900class Semaphore : public StackObj { 1901 public: 1902 Semaphore(); 1903 ~Semaphore(); 1904 void signal(); 1905 void wait(); 1906 bool trywait(); 1907 bool timedwait(unsigned int sec, int nsec); 1908 private: 1909 jlong currenttime() const; 1910 os_semaphore_t _semaphore; 1911}; 1912 1913Semaphore::Semaphore() : _semaphore(0) { 1914 SEM_INIT(_semaphore, 0); 1915} 1916 1917Semaphore::~Semaphore() { 1918 SEM_DESTROY(_semaphore); 1919} 1920 1921void Semaphore::signal() { 1922 SEM_POST(_semaphore); 1923} 1924 1925void Semaphore::wait() { 1926 SEM_WAIT(_semaphore); 1927} 1928 1929jlong Semaphore::currenttime() const { 1930 struct timeval tv; 1931 gettimeofday(&tv, NULL); 1932 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1933} 1934 1935#ifdef __APPLE__ 1936bool Semaphore::trywait() { 1937 return timedwait(0, 0); 1938} 1939 1940bool Semaphore::timedwait(unsigned int sec, int nsec) { 1941 kern_return_t kr = KERN_ABORTED; 1942 mach_timespec_t waitspec; 1943 waitspec.tv_sec = sec; 1944 waitspec.tv_nsec = nsec; 1945 1946 jlong starttime = currenttime(); 1947 1948 kr = semaphore_timedwait(_semaphore, waitspec); 1949 while (kr == KERN_ABORTED) { 1950 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1951 1952 jlong current = currenttime(); 1953 jlong passedtime = current - starttime; 1954 1955 if (passedtime >= totalwait) { 1956 waitspec.tv_sec = 0; 1957 waitspec.tv_nsec = 0; 1958 } else { 1959 jlong waittime = totalwait - (current - starttime); 1960 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 1961 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 1962 } 1963 1964 kr = semaphore_timedwait(_semaphore, waitspec); 1965 } 1966 1967 return kr == KERN_SUCCESS; 1968} 1969 1970#else 1971 1972bool Semaphore::trywait() { 1973 return sem_trywait(&_semaphore) == 0; 1974} 1975 1976bool Semaphore::timedwait(unsigned int sec, int nsec) { 1977 struct timespec ts; 1978 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 1979 1980 while (1) { 1981 int result = sem_timedwait(&_semaphore, &ts); 1982 if (result == 0) { 1983 return true; 1984 } else if (errno == EINTR) { 1985 continue; 1986 } else if (errno == ETIMEDOUT) { 1987 return false; 1988 } else { 1989 return false; 1990 } 1991 } 1992} 1993 1994#endif // __APPLE__ 1995 1996static os_semaphore_t sig_sem; 1997static Semaphore sr_semaphore; 1998 1999void os::signal_init_pd() { 2000 // Initialize signal structures 2001 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2002 2003 // Initialize signal semaphore 2004 ::SEM_INIT(sig_sem, 0); 2005} 2006 2007void os::signal_notify(int sig) { 2008 Atomic::inc(&pending_signals[sig]); 2009 ::SEM_POST(sig_sem); 2010} 2011 2012static int check_pending_signals(bool wait) { 2013 Atomic::store(0, &sigint_count); 2014 for (;;) { 2015 for (int i = 0; i < NSIG + 1; i++) { 2016 jint n = pending_signals[i]; 2017 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2018 return i; 2019 } 2020 } 2021 if (!wait) { 2022 return -1; 2023 } 2024 JavaThread *thread = JavaThread::current(); 2025 ThreadBlockInVM tbivm(thread); 2026 2027 bool threadIsSuspended; 2028 do { 2029 thread->set_suspend_equivalent(); 2030 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2031 ::SEM_WAIT(sig_sem); 2032 2033 // were we externally suspended while we were waiting? 2034 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2035 if (threadIsSuspended) { 2036 // 2037 // The semaphore has been incremented, but while we were waiting 2038 // another thread suspended us. We don't want to continue running 2039 // while suspended because that would surprise the thread that 2040 // suspended us. 2041 // 2042 ::SEM_POST(sig_sem); 2043 2044 thread->java_suspend_self(); 2045 } 2046 } while (threadIsSuspended); 2047 } 2048} 2049 2050int os::signal_lookup() { 2051 return check_pending_signals(false); 2052} 2053 2054int os::signal_wait() { 2055 return check_pending_signals(true); 2056} 2057 2058//////////////////////////////////////////////////////////////////////////////// 2059// Virtual Memory 2060 2061int os::vm_page_size() { 2062 // Seems redundant as all get out 2063 assert(os::Bsd::page_size() != -1, "must call os::init"); 2064 return os::Bsd::page_size(); 2065} 2066 2067// Solaris allocates memory by pages. 2068int os::vm_allocation_granularity() { 2069 assert(os::Bsd::page_size() != -1, "must call os::init"); 2070 return os::Bsd::page_size(); 2071} 2072 2073// Rationale behind this function: 2074// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2075// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2076// samples for JITted code. Here we create private executable mapping over the code cache 2077// and then we can use standard (well, almost, as mapping can change) way to provide 2078// info for the reporting script by storing timestamp and location of symbol 2079void bsd_wrap_code(char* base, size_t size) { 2080 static volatile jint cnt = 0; 2081 2082 if (!UseOprofile) { 2083 return; 2084 } 2085 2086 char buf[PATH_MAX + 1]; 2087 int num = Atomic::add(1, &cnt); 2088 2089 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2090 os::get_temp_directory(), os::current_process_id(), num); 2091 unlink(buf); 2092 2093 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2094 2095 if (fd != -1) { 2096 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2097 if (rv != (off_t)-1) { 2098 if (::write(fd, "", 1) == 1) { 2099 mmap(base, size, 2100 PROT_READ|PROT_WRITE|PROT_EXEC, 2101 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2102 } 2103 } 2104 ::close(fd); 2105 unlink(buf); 2106 } 2107} 2108 2109static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2110 int err) { 2111 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2112 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2113 strerror(err), err); 2114} 2115 2116// NOTE: Bsd kernel does not really reserve the pages for us. 2117// All it does is to check if there are enough free pages 2118// left at the time of mmap(). This could be a potential 2119// problem. 2120bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2121 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2122#ifdef __OpenBSD__ 2123 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2124 if (::mprotect(addr, size, prot) == 0) { 2125 return true; 2126 } 2127#else 2128 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2129 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2130 if (res != (uintptr_t) MAP_FAILED) { 2131 return true; 2132 } 2133#endif 2134 2135 // Warn about any commit errors we see in non-product builds just 2136 // in case mmap() doesn't work as described on the man page. 2137 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2138 2139 return false; 2140} 2141 2142bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2143 bool exec) { 2144 // alignment_hint is ignored on this OS 2145 return pd_commit_memory(addr, size, exec); 2146} 2147 2148void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2149 const char* mesg) { 2150 assert(mesg != NULL, "mesg must be specified"); 2151 if (!pd_commit_memory(addr, size, exec)) { 2152 // add extra info in product mode for vm_exit_out_of_memory(): 2153 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2154 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2155 } 2156} 2157 2158void os::pd_commit_memory_or_exit(char* addr, size_t size, 2159 size_t alignment_hint, bool exec, 2160 const char* mesg) { 2161 // alignment_hint is ignored on this OS 2162 pd_commit_memory_or_exit(addr, size, exec, mesg); 2163} 2164 2165void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2166} 2167 2168void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2169 ::madvise(addr, bytes, MADV_DONTNEED); 2170} 2171 2172void os::numa_make_global(char *addr, size_t bytes) { 2173} 2174 2175void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2176} 2177 2178bool os::numa_topology_changed() { return false; } 2179 2180size_t os::numa_get_groups_num() { 2181 return 1; 2182} 2183 2184int os::numa_get_group_id() { 2185 return 0; 2186} 2187 2188size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2189 if (size > 0) { 2190 ids[0] = 0; 2191 return 1; 2192 } 2193 return 0; 2194} 2195 2196bool os::get_page_info(char *start, page_info* info) { 2197 return false; 2198} 2199 2200char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2201 return end; 2202} 2203 2204 2205bool os::pd_uncommit_memory(char* addr, size_t size) { 2206#ifdef __OpenBSD__ 2207 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2208 return ::mprotect(addr, size, PROT_NONE) == 0; 2209#else 2210 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2211 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2212 return res != (uintptr_t) MAP_FAILED; 2213#endif 2214} 2215 2216bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2217 return os::commit_memory(addr, size, !ExecMem); 2218} 2219 2220// If this is a growable mapping, remove the guard pages entirely by 2221// munmap()ping them. If not, just call uncommit_memory(). 2222bool os::remove_stack_guard_pages(char* addr, size_t size) { 2223 return os::uncommit_memory(addr, size); 2224} 2225 2226static address _highest_vm_reserved_address = NULL; 2227 2228// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2229// at 'requested_addr'. If there are existing memory mappings at the same 2230// location, however, they will be overwritten. If 'fixed' is false, 2231// 'requested_addr' is only treated as a hint, the return value may or 2232// may not start from the requested address. Unlike Bsd mmap(), this 2233// function returns NULL to indicate failure. 2234static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2235 char * addr; 2236 int flags; 2237 2238 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2239 if (fixed) { 2240 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2241 flags |= MAP_FIXED; 2242 } 2243 2244 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2245 // touch an uncommitted page. Otherwise, the read/write might 2246 // succeed if we have enough swap space to back the physical page. 2247 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2248 flags, -1, 0); 2249 2250 if (addr != MAP_FAILED) { 2251 // anon_mmap() should only get called during VM initialization, 2252 // don't need lock (actually we can skip locking even it can be called 2253 // from multiple threads, because _highest_vm_reserved_address is just a 2254 // hint about the upper limit of non-stack memory regions.) 2255 if ((address)addr + bytes > _highest_vm_reserved_address) { 2256 _highest_vm_reserved_address = (address)addr + bytes; 2257 } 2258 } 2259 2260 return addr == MAP_FAILED ? NULL : addr; 2261} 2262 2263// Don't update _highest_vm_reserved_address, because there might be memory 2264// regions above addr + size. If so, releasing a memory region only creates 2265// a hole in the address space, it doesn't help prevent heap-stack collision. 2266// 2267static int anon_munmap(char * addr, size_t size) { 2268 return ::munmap(addr, size) == 0; 2269} 2270 2271char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2272 size_t alignment_hint) { 2273 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2274} 2275 2276bool os::pd_release_memory(char* addr, size_t size) { 2277 return anon_munmap(addr, size); 2278} 2279 2280static bool bsd_mprotect(char* addr, size_t size, int prot) { 2281 // Bsd wants the mprotect address argument to be page aligned. 2282 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2283 2284 // According to SUSv3, mprotect() should only be used with mappings 2285 // established by mmap(), and mmap() always maps whole pages. Unaligned 2286 // 'addr' likely indicates problem in the VM (e.g. trying to change 2287 // protection of malloc'ed or statically allocated memory). Check the 2288 // caller if you hit this assert. 2289 assert(addr == bottom, "sanity check"); 2290 2291 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2292 return ::mprotect(bottom, size, prot) == 0; 2293} 2294 2295// Set protections specified 2296bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2297 bool is_committed) { 2298 unsigned int p = 0; 2299 switch (prot) { 2300 case MEM_PROT_NONE: p = PROT_NONE; break; 2301 case MEM_PROT_READ: p = PROT_READ; break; 2302 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2303 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2304 default: 2305 ShouldNotReachHere(); 2306 } 2307 // is_committed is unused. 2308 return bsd_mprotect(addr, bytes, p); 2309} 2310 2311bool os::guard_memory(char* addr, size_t size) { 2312 return bsd_mprotect(addr, size, PROT_NONE); 2313} 2314 2315bool os::unguard_memory(char* addr, size_t size) { 2316 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2317} 2318 2319bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2320 return false; 2321} 2322 2323// Large page support 2324 2325static size_t _large_page_size = 0; 2326 2327void os::large_page_init() { 2328} 2329 2330 2331char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2332 fatal("This code is not used or maintained."); 2333 2334 // "exec" is passed in but not used. Creating the shared image for 2335 // the code cache doesn't have an SHM_X executable permission to check. 2336 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2337 2338 key_t key = IPC_PRIVATE; 2339 char *addr; 2340 2341 bool warn_on_failure = UseLargePages && 2342 (!FLAG_IS_DEFAULT(UseLargePages) || 2343 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2344 ); 2345 char msg[128]; 2346 2347 // Create a large shared memory region to attach to based on size. 2348 // Currently, size is the total size of the heap 2349 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2350 if (shmid == -1) { 2351 // Possible reasons for shmget failure: 2352 // 1. shmmax is too small for Java heap. 2353 // > check shmmax value: cat /proc/sys/kernel/shmmax 2354 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2355 // 2. not enough large page memory. 2356 // > check available large pages: cat /proc/meminfo 2357 // > increase amount of large pages: 2358 // echo new_value > /proc/sys/vm/nr_hugepages 2359 // Note 1: different Bsd may use different name for this property, 2360 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2361 // Note 2: it's possible there's enough physical memory available but 2362 // they are so fragmented after a long run that they can't 2363 // coalesce into large pages. Try to reserve large pages when 2364 // the system is still "fresh". 2365 if (warn_on_failure) { 2366 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 2367 warning(msg); 2368 } 2369 return NULL; 2370 } 2371 2372 // attach to the region 2373 addr = (char*)shmat(shmid, req_addr, 0); 2374 int err = errno; 2375 2376 // Remove shmid. If shmat() is successful, the actual shared memory segment 2377 // will be deleted when it's detached by shmdt() or when the process 2378 // terminates. If shmat() is not successful this will remove the shared 2379 // segment immediately. 2380 shmctl(shmid, IPC_RMID, NULL); 2381 2382 if ((intptr_t)addr == -1) { 2383 if (warn_on_failure) { 2384 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 2385 warning(msg); 2386 } 2387 return NULL; 2388 } 2389 2390 // The memory is committed 2391 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC); 2392 2393 return addr; 2394} 2395 2396bool os::release_memory_special(char* base, size_t bytes) { 2397 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2398 // detaching the SHM segment will also delete it, see reserve_memory_special() 2399 int rslt = shmdt(base); 2400 if (rslt == 0) { 2401 tkr.record((address)base, bytes); 2402 return true; 2403 } else { 2404 tkr.discard(); 2405 return false; 2406 } 2407 2408} 2409 2410size_t os::large_page_size() { 2411 return _large_page_size; 2412} 2413 2414// HugeTLBFS allows application to commit large page memory on demand; 2415// with SysV SHM the entire memory region must be allocated as shared 2416// memory. 2417bool os::can_commit_large_page_memory() { 2418 return UseHugeTLBFS; 2419} 2420 2421bool os::can_execute_large_page_memory() { 2422 return UseHugeTLBFS; 2423} 2424 2425// Reserve memory at an arbitrary address, only if that area is 2426// available (and not reserved for something else). 2427 2428char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2429 const int max_tries = 10; 2430 char* base[max_tries]; 2431 size_t size[max_tries]; 2432 const size_t gap = 0x000000; 2433 2434 // Assert only that the size is a multiple of the page size, since 2435 // that's all that mmap requires, and since that's all we really know 2436 // about at this low abstraction level. If we need higher alignment, 2437 // we can either pass an alignment to this method or verify alignment 2438 // in one of the methods further up the call chain. See bug 5044738. 2439 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2440 2441 // Repeatedly allocate blocks until the block is allocated at the 2442 // right spot. Give up after max_tries. Note that reserve_memory() will 2443 // automatically update _highest_vm_reserved_address if the call is 2444 // successful. The variable tracks the highest memory address every reserved 2445 // by JVM. It is used to detect heap-stack collision if running with 2446 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2447 // space than needed, it could confuse the collision detecting code. To 2448 // solve the problem, save current _highest_vm_reserved_address and 2449 // calculate the correct value before return. 2450 address old_highest = _highest_vm_reserved_address; 2451 2452 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2453 // if kernel honors the hint then we can return immediately. 2454 char * addr = anon_mmap(requested_addr, bytes, false); 2455 if (addr == requested_addr) { 2456 return requested_addr; 2457 } 2458 2459 if (addr != NULL) { 2460 // mmap() is successful but it fails to reserve at the requested address 2461 anon_munmap(addr, bytes); 2462 } 2463 2464 int i; 2465 for (i = 0; i < max_tries; ++i) { 2466 base[i] = reserve_memory(bytes); 2467 2468 if (base[i] != NULL) { 2469 // Is this the block we wanted? 2470 if (base[i] == requested_addr) { 2471 size[i] = bytes; 2472 break; 2473 } 2474 2475 // Does this overlap the block we wanted? Give back the overlapped 2476 // parts and try again. 2477 2478 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2479 if (top_overlap >= 0 && top_overlap < bytes) { 2480 unmap_memory(base[i], top_overlap); 2481 base[i] += top_overlap; 2482 size[i] = bytes - top_overlap; 2483 } else { 2484 size_t bottom_overlap = base[i] + bytes - requested_addr; 2485 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2486 unmap_memory(requested_addr, bottom_overlap); 2487 size[i] = bytes - bottom_overlap; 2488 } else { 2489 size[i] = bytes; 2490 } 2491 } 2492 } 2493 } 2494 2495 // Give back the unused reserved pieces. 2496 2497 for (int j = 0; j < i; ++j) { 2498 if (base[j] != NULL) { 2499 unmap_memory(base[j], size[j]); 2500 } 2501 } 2502 2503 if (i < max_tries) { 2504 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2505 return requested_addr; 2506 } else { 2507 _highest_vm_reserved_address = old_highest; 2508 return NULL; 2509 } 2510} 2511 2512size_t os::read(int fd, void *buf, unsigned int nBytes) { 2513 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2514} 2515 2516// TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation. 2517// Solaris uses poll(), bsd uses park(). 2518// Poll() is likely a better choice, assuming that Thread.interrupt() 2519// generates a SIGUSRx signal. Note that SIGUSR1 can interfere with 2520// SIGSEGV, see 4355769. 2521 2522int os::sleep(Thread* thread, jlong millis, bool interruptible) { 2523 assert(thread == Thread::current(), "thread consistency check"); 2524 2525 ParkEvent * const slp = thread->_SleepEvent ; 2526 slp->reset() ; 2527 OrderAccess::fence() ; 2528 2529 if (interruptible) { 2530 jlong prevtime = javaTimeNanos(); 2531 2532 for (;;) { 2533 if (os::is_interrupted(thread, true)) { 2534 return OS_INTRPT; 2535 } 2536 2537 jlong newtime = javaTimeNanos(); 2538 2539 if (newtime - prevtime < 0) { 2540 // time moving backwards, should only happen if no monotonic clock 2541 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2542 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2543 } else { 2544 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2545 } 2546 2547 if(millis <= 0) { 2548 return OS_OK; 2549 } 2550 2551 prevtime = newtime; 2552 2553 { 2554 assert(thread->is_Java_thread(), "sanity check"); 2555 JavaThread *jt = (JavaThread *) thread; 2556 ThreadBlockInVM tbivm(jt); 2557 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 2558 2559 jt->set_suspend_equivalent(); 2560 // cleared by handle_special_suspend_equivalent_condition() or 2561 // java_suspend_self() via check_and_wait_while_suspended() 2562 2563 slp->park(millis); 2564 2565 // were we externally suspended while we were waiting? 2566 jt->check_and_wait_while_suspended(); 2567 } 2568 } 2569 } else { 2570 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 2571 jlong prevtime = javaTimeNanos(); 2572 2573 for (;;) { 2574 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 2575 // the 1st iteration ... 2576 jlong newtime = javaTimeNanos(); 2577 2578 if (newtime - prevtime < 0) { 2579 // time moving backwards, should only happen if no monotonic clock 2580 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2581 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2582 } else { 2583 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2584 } 2585 2586 if(millis <= 0) break ; 2587 2588 prevtime = newtime; 2589 slp->park(millis); 2590 } 2591 return OS_OK ; 2592 } 2593} 2594 2595void os::naked_short_sleep(jlong ms) { 2596 struct timespec req; 2597 2598 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2599 req.tv_sec = 0; 2600 if (ms > 0) { 2601 req.tv_nsec = (ms % 1000) * 1000000; 2602 } 2603 else { 2604 req.tv_nsec = 1; 2605 } 2606 2607 nanosleep(&req, NULL); 2608 2609 return; 2610} 2611 2612// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2613void os::infinite_sleep() { 2614 while (true) { // sleep forever ... 2615 ::sleep(100); // ... 100 seconds at a time 2616 } 2617} 2618 2619// Used to convert frequent JVM_Yield() to nops 2620bool os::dont_yield() { 2621 return DontYieldALot; 2622} 2623 2624void os::yield() { 2625 sched_yield(); 2626} 2627 2628os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 2629 2630void os::yield_all(int attempts) { 2631 // Yields to all threads, including threads with lower priorities 2632 // Threads on Bsd are all with same priority. The Solaris style 2633 // os::yield_all() with nanosleep(1ms) is not necessary. 2634 sched_yield(); 2635} 2636 2637// Called from the tight loops to possibly influence time-sharing heuristics 2638void os::loop_breaker(int attempts) { 2639 os::yield_all(attempts); 2640} 2641 2642//////////////////////////////////////////////////////////////////////////////// 2643// thread priority support 2644 2645// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2646// only supports dynamic priority, static priority must be zero. For real-time 2647// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2648// However, for large multi-threaded applications, SCHED_RR is not only slower 2649// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2650// of 5 runs - Sep 2005). 2651// 2652// The following code actually changes the niceness of kernel-thread/LWP. It 2653// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2654// not the entire user process, and user level threads are 1:1 mapped to kernel 2655// threads. It has always been the case, but could change in the future. For 2656// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2657// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2658 2659#if !defined(__APPLE__) 2660int os::java_to_os_priority[CriticalPriority + 1] = { 2661 19, // 0 Entry should never be used 2662 2663 0, // 1 MinPriority 2664 3, // 2 2665 6, // 3 2666 2667 10, // 4 2668 15, // 5 NormPriority 2669 18, // 6 2670 2671 21, // 7 2672 25, // 8 2673 28, // 9 NearMaxPriority 2674 2675 31, // 10 MaxPriority 2676 2677 31 // 11 CriticalPriority 2678}; 2679#else 2680/* Using Mach high-level priority assignments */ 2681int os::java_to_os_priority[CriticalPriority + 1] = { 2682 0, // 0 Entry should never be used (MINPRI_USER) 2683 2684 27, // 1 MinPriority 2685 28, // 2 2686 29, // 3 2687 2688 30, // 4 2689 31, // 5 NormPriority (BASEPRI_DEFAULT) 2690 32, // 6 2691 2692 33, // 7 2693 34, // 8 2694 35, // 9 NearMaxPriority 2695 2696 36, // 10 MaxPriority 2697 2698 36 // 11 CriticalPriority 2699}; 2700#endif 2701 2702static int prio_init() { 2703 if (ThreadPriorityPolicy == 1) { 2704 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2705 // if effective uid is not root. Perhaps, a more elegant way of doing 2706 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2707 if (geteuid() != 0) { 2708 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2709 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2710 } 2711 ThreadPriorityPolicy = 0; 2712 } 2713 } 2714 if (UseCriticalJavaThreadPriority) { 2715 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2716 } 2717 return 0; 2718} 2719 2720OSReturn os::set_native_priority(Thread* thread, int newpri) { 2721 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 2722 2723#ifdef __OpenBSD__ 2724 // OpenBSD pthread_setprio starves low priority threads 2725 return OS_OK; 2726#elif defined(__FreeBSD__) 2727 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2728#elif defined(__APPLE__) || defined(__NetBSD__) 2729 struct sched_param sp; 2730 int policy; 2731 pthread_t self = pthread_self(); 2732 2733 if (pthread_getschedparam(self, &policy, &sp) != 0) 2734 return OS_ERR; 2735 2736 sp.sched_priority = newpri; 2737 if (pthread_setschedparam(self, policy, &sp) != 0) 2738 return OS_ERR; 2739 2740 return OS_OK; 2741#else 2742 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2743 return (ret == 0) ? OS_OK : OS_ERR; 2744#endif 2745} 2746 2747OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2748 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 2749 *priority_ptr = java_to_os_priority[NormPriority]; 2750 return OS_OK; 2751 } 2752 2753 errno = 0; 2754#if defined(__OpenBSD__) || defined(__FreeBSD__) 2755 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2756#elif defined(__APPLE__) || defined(__NetBSD__) 2757 int policy; 2758 struct sched_param sp; 2759 2760 pthread_getschedparam(pthread_self(), &policy, &sp); 2761 *priority_ptr = sp.sched_priority; 2762#else 2763 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2764#endif 2765 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2766} 2767 2768// Hint to the underlying OS that a task switch would not be good. 2769// Void return because it's a hint and can fail. 2770void os::hint_no_preempt() {} 2771 2772//////////////////////////////////////////////////////////////////////////////// 2773// suspend/resume support 2774 2775// the low-level signal-based suspend/resume support is a remnant from the 2776// old VM-suspension that used to be for java-suspension, safepoints etc, 2777// within hotspot. Now there is a single use-case for this: 2778// - calling get_thread_pc() on the VMThread by the flat-profiler task 2779// that runs in the watcher thread. 2780// The remaining code is greatly simplified from the more general suspension 2781// code that used to be used. 2782// 2783// The protocol is quite simple: 2784// - suspend: 2785// - sends a signal to the target thread 2786// - polls the suspend state of the osthread using a yield loop 2787// - target thread signal handler (SR_handler) sets suspend state 2788// and blocks in sigsuspend until continued 2789// - resume: 2790// - sets target osthread state to continue 2791// - sends signal to end the sigsuspend loop in the SR_handler 2792// 2793// Note that the SR_lock plays no role in this suspend/resume protocol. 2794// 2795 2796static void resume_clear_context(OSThread *osthread) { 2797 osthread->set_ucontext(NULL); 2798 osthread->set_siginfo(NULL); 2799} 2800 2801static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2802 osthread->set_ucontext(context); 2803 osthread->set_siginfo(siginfo); 2804} 2805 2806// 2807// Handler function invoked when a thread's execution is suspended or 2808// resumed. We have to be careful that only async-safe functions are 2809// called here (Note: most pthread functions are not async safe and 2810// should be avoided.) 2811// 2812// Note: sigwait() is a more natural fit than sigsuspend() from an 2813// interface point of view, but sigwait() prevents the signal hander 2814// from being run. libpthread would get very confused by not having 2815// its signal handlers run and prevents sigwait()'s use with the 2816// mutex granting granting signal. 2817// 2818// Currently only ever called on the VMThread or JavaThread 2819// 2820static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2821 // Save and restore errno to avoid confusing native code with EINTR 2822 // after sigsuspend. 2823 int old_errno = errno; 2824 2825 Thread* thread = Thread::current(); 2826 OSThread* osthread = thread->osthread(); 2827 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2828 2829 os::SuspendResume::State current = osthread->sr.state(); 2830 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2831 suspend_save_context(osthread, siginfo, context); 2832 2833 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2834 os::SuspendResume::State state = osthread->sr.suspended(); 2835 if (state == os::SuspendResume::SR_SUSPENDED) { 2836 sigset_t suspend_set; // signals for sigsuspend() 2837 2838 // get current set of blocked signals and unblock resume signal 2839 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2840 sigdelset(&suspend_set, SR_signum); 2841 2842 sr_semaphore.signal(); 2843 // wait here until we are resumed 2844 while (1) { 2845 sigsuspend(&suspend_set); 2846 2847 os::SuspendResume::State result = osthread->sr.running(); 2848 if (result == os::SuspendResume::SR_RUNNING) { 2849 sr_semaphore.signal(); 2850 break; 2851 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2852 ShouldNotReachHere(); 2853 } 2854 } 2855 2856 } else if (state == os::SuspendResume::SR_RUNNING) { 2857 // request was cancelled, continue 2858 } else { 2859 ShouldNotReachHere(); 2860 } 2861 2862 resume_clear_context(osthread); 2863 } else if (current == os::SuspendResume::SR_RUNNING) { 2864 // request was cancelled, continue 2865 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2866 // ignore 2867 } else { 2868 // ignore 2869 } 2870 2871 errno = old_errno; 2872} 2873 2874 2875static int SR_initialize() { 2876 struct sigaction act; 2877 char *s; 2878 /* Get signal number to use for suspend/resume */ 2879 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2880 int sig = ::strtol(s, 0, 10); 2881 if (sig > 0 || sig < NSIG) { 2882 SR_signum = sig; 2883 } 2884 } 2885 2886 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2887 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2888 2889 sigemptyset(&SR_sigset); 2890 sigaddset(&SR_sigset, SR_signum); 2891 2892 /* Set up signal handler for suspend/resume */ 2893 act.sa_flags = SA_RESTART|SA_SIGINFO; 2894 act.sa_handler = (void (*)(int)) SR_handler; 2895 2896 // SR_signum is blocked by default. 2897 // 4528190 - We also need to block pthread restart signal (32 on all 2898 // supported Bsd platforms). Note that BsdThreads need to block 2899 // this signal for all threads to work properly. So we don't have 2900 // to use hard-coded signal number when setting up the mask. 2901 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2902 2903 if (sigaction(SR_signum, &act, 0) == -1) { 2904 return -1; 2905 } 2906 2907 // Save signal flag 2908 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2909 return 0; 2910} 2911 2912static int sr_notify(OSThread* osthread) { 2913 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2914 assert_status(status == 0, status, "pthread_kill"); 2915 return status; 2916} 2917 2918// "Randomly" selected value for how long we want to spin 2919// before bailing out on suspending a thread, also how often 2920// we send a signal to a thread we want to resume 2921static const int RANDOMLY_LARGE_INTEGER = 1000000; 2922static const int RANDOMLY_LARGE_INTEGER2 = 100; 2923 2924// returns true on success and false on error - really an error is fatal 2925// but this seems the normal response to library errors 2926static bool do_suspend(OSThread* osthread) { 2927 assert(osthread->sr.is_running(), "thread should be running"); 2928 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2929 2930 // mark as suspended and send signal 2931 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2932 // failed to switch, state wasn't running? 2933 ShouldNotReachHere(); 2934 return false; 2935 } 2936 2937 if (sr_notify(osthread) != 0) { 2938 ShouldNotReachHere(); 2939 } 2940 2941 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2942 while (true) { 2943 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2944 break; 2945 } else { 2946 // timeout 2947 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2948 if (cancelled == os::SuspendResume::SR_RUNNING) { 2949 return false; 2950 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2951 // make sure that we consume the signal on the semaphore as well 2952 sr_semaphore.wait(); 2953 break; 2954 } else { 2955 ShouldNotReachHere(); 2956 return false; 2957 } 2958 } 2959 } 2960 2961 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2962 return true; 2963} 2964 2965static void do_resume(OSThread* osthread) { 2966 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2967 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2968 2969 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2970 // failed to switch to WAKEUP_REQUEST 2971 ShouldNotReachHere(); 2972 return; 2973 } 2974 2975 while (true) { 2976 if (sr_notify(osthread) == 0) { 2977 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2978 if (osthread->sr.is_running()) { 2979 return; 2980 } 2981 } 2982 } else { 2983 ShouldNotReachHere(); 2984 } 2985 } 2986 2987 guarantee(osthread->sr.is_running(), "Must be running!"); 2988} 2989 2990//////////////////////////////////////////////////////////////////////////////// 2991// interrupt support 2992 2993void os::interrupt(Thread* thread) { 2994 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 2995 "possibility of dangling Thread pointer"); 2996 2997 OSThread* osthread = thread->osthread(); 2998 2999 if (!osthread->interrupted()) { 3000 osthread->set_interrupted(true); 3001 // More than one thread can get here with the same value of osthread, 3002 // resulting in multiple notifications. We do, however, want the store 3003 // to interrupted() to be visible to other threads before we execute unpark(). 3004 OrderAccess::fence(); 3005 ParkEvent * const slp = thread->_SleepEvent ; 3006 if (slp != NULL) slp->unpark() ; 3007 } 3008 3009 // For JSR166. Unpark even if interrupt status already was set 3010 if (thread->is_Java_thread()) 3011 ((JavaThread*)thread)->parker()->unpark(); 3012 3013 ParkEvent * ev = thread->_ParkEvent ; 3014 if (ev != NULL) ev->unpark() ; 3015 3016} 3017 3018bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 3019 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3020 "possibility of dangling Thread pointer"); 3021 3022 OSThread* osthread = thread->osthread(); 3023 3024 bool interrupted = osthread->interrupted(); 3025 3026 if (interrupted && clear_interrupted) { 3027 osthread->set_interrupted(false); 3028 // consider thread->_SleepEvent->reset() ... optional optimization 3029 } 3030 3031 return interrupted; 3032} 3033 3034/////////////////////////////////////////////////////////////////////////////////// 3035// signal handling (except suspend/resume) 3036 3037// This routine may be used by user applications as a "hook" to catch signals. 3038// The user-defined signal handler must pass unrecognized signals to this 3039// routine, and if it returns true (non-zero), then the signal handler must 3040// return immediately. If the flag "abort_if_unrecognized" is true, then this 3041// routine will never retun false (zero), but instead will execute a VM panic 3042// routine kill the process. 3043// 3044// If this routine returns false, it is OK to call it again. This allows 3045// the user-defined signal handler to perform checks either before or after 3046// the VM performs its own checks. Naturally, the user code would be making 3047// a serious error if it tried to handle an exception (such as a null check 3048// or breakpoint) that the VM was generating for its own correct operation. 3049// 3050// This routine may recognize any of the following kinds of signals: 3051// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 3052// It should be consulted by handlers for any of those signals. 3053// 3054// The caller of this routine must pass in the three arguments supplied 3055// to the function referred to in the "sa_sigaction" (not the "sa_handler") 3056// field of the structure passed to sigaction(). This routine assumes that 3057// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 3058// 3059// Note that the VM will print warnings if it detects conflicting signal 3060// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 3061// 3062extern "C" JNIEXPORT int 3063JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 3064 void* ucontext, int abort_if_unrecognized); 3065 3066void signalHandler(int sig, siginfo_t* info, void* uc) { 3067 assert(info != NULL && uc != NULL, "it must be old kernel"); 3068 int orig_errno = errno; // Preserve errno value over signal handler. 3069 JVM_handle_bsd_signal(sig, info, uc, true); 3070 errno = orig_errno; 3071} 3072 3073 3074// This boolean allows users to forward their own non-matching signals 3075// to JVM_handle_bsd_signal, harmlessly. 3076bool os::Bsd::signal_handlers_are_installed = false; 3077 3078// For signal-chaining 3079struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3080unsigned int os::Bsd::sigs = 0; 3081bool os::Bsd::libjsig_is_loaded = false; 3082typedef struct sigaction *(*get_signal_t)(int); 3083get_signal_t os::Bsd::get_signal_action = NULL; 3084 3085struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3086 struct sigaction *actp = NULL; 3087 3088 if (libjsig_is_loaded) { 3089 // Retrieve the old signal handler from libjsig 3090 actp = (*get_signal_action)(sig); 3091 } 3092 if (actp == NULL) { 3093 // Retrieve the preinstalled signal handler from jvm 3094 actp = get_preinstalled_handler(sig); 3095 } 3096 3097 return actp; 3098} 3099 3100static bool call_chained_handler(struct sigaction *actp, int sig, 3101 siginfo_t *siginfo, void *context) { 3102 // Call the old signal handler 3103 if (actp->sa_handler == SIG_DFL) { 3104 // It's more reasonable to let jvm treat it as an unexpected exception 3105 // instead of taking the default action. 3106 return false; 3107 } else if (actp->sa_handler != SIG_IGN) { 3108 if ((actp->sa_flags & SA_NODEFER) == 0) { 3109 // automaticlly block the signal 3110 sigaddset(&(actp->sa_mask), sig); 3111 } 3112 3113 sa_handler_t hand; 3114 sa_sigaction_t sa; 3115 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3116 // retrieve the chained handler 3117 if (siginfo_flag_set) { 3118 sa = actp->sa_sigaction; 3119 } else { 3120 hand = actp->sa_handler; 3121 } 3122 3123 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3124 actp->sa_handler = SIG_DFL; 3125 } 3126 3127 // try to honor the signal mask 3128 sigset_t oset; 3129 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3130 3131 // call into the chained handler 3132 if (siginfo_flag_set) { 3133 (*sa)(sig, siginfo, context); 3134 } else { 3135 (*hand)(sig); 3136 } 3137 3138 // restore the signal mask 3139 pthread_sigmask(SIG_SETMASK, &oset, 0); 3140 } 3141 // Tell jvm's signal handler the signal is taken care of. 3142 return true; 3143} 3144 3145bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3146 bool chained = false; 3147 // signal-chaining 3148 if (UseSignalChaining) { 3149 struct sigaction *actp = get_chained_signal_action(sig); 3150 if (actp != NULL) { 3151 chained = call_chained_handler(actp, sig, siginfo, context); 3152 } 3153 } 3154 return chained; 3155} 3156 3157struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3158 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 3159 return &sigact[sig]; 3160 } 3161 return NULL; 3162} 3163 3164void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3165 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3166 sigact[sig] = oldAct; 3167 sigs |= (unsigned int)1 << sig; 3168} 3169 3170// for diagnostic 3171int os::Bsd::sigflags[MAXSIGNUM]; 3172 3173int os::Bsd::get_our_sigflags(int sig) { 3174 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3175 return sigflags[sig]; 3176} 3177 3178void os::Bsd::set_our_sigflags(int sig, int flags) { 3179 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3180 sigflags[sig] = flags; 3181} 3182 3183void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3184 // Check for overwrite. 3185 struct sigaction oldAct; 3186 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3187 3188 void* oldhand = oldAct.sa_sigaction 3189 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3190 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3191 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3192 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3193 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3194 if (AllowUserSignalHandlers || !set_installed) { 3195 // Do not overwrite; user takes responsibility to forward to us. 3196 return; 3197 } else if (UseSignalChaining) { 3198 // save the old handler in jvm 3199 save_preinstalled_handler(sig, oldAct); 3200 // libjsig also interposes the sigaction() call below and saves the 3201 // old sigaction on it own. 3202 } else { 3203 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3204 "%#lx for signal %d.", (long)oldhand, sig)); 3205 } 3206 } 3207 3208 struct sigaction sigAct; 3209 sigfillset(&(sigAct.sa_mask)); 3210 sigAct.sa_handler = SIG_DFL; 3211 if (!set_installed) { 3212 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3213 } else { 3214 sigAct.sa_sigaction = signalHandler; 3215 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3216 } 3217#if __APPLE__ 3218 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3219 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3220 // if the signal handler declares it will handle it on alternate stack. 3221 // Notice we only declare we will handle it on alt stack, but we are not 3222 // actually going to use real alt stack - this is just a workaround. 3223 // Please see ux_exception.c, method catch_mach_exception_raise for details 3224 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3225 if (sig == SIGSEGV) { 3226 sigAct.sa_flags |= SA_ONSTACK; 3227 } 3228#endif 3229 3230 // Save flags, which are set by ours 3231 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3232 sigflags[sig] = sigAct.sa_flags; 3233 3234 int ret = sigaction(sig, &sigAct, &oldAct); 3235 assert(ret == 0, "check"); 3236 3237 void* oldhand2 = oldAct.sa_sigaction 3238 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3239 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3240 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3241} 3242 3243// install signal handlers for signals that HotSpot needs to 3244// handle in order to support Java-level exception handling. 3245 3246void os::Bsd::install_signal_handlers() { 3247 if (!signal_handlers_are_installed) { 3248 signal_handlers_are_installed = true; 3249 3250 // signal-chaining 3251 typedef void (*signal_setting_t)(); 3252 signal_setting_t begin_signal_setting = NULL; 3253 signal_setting_t end_signal_setting = NULL; 3254 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3255 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3256 if (begin_signal_setting != NULL) { 3257 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3258 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3259 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3260 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3261 libjsig_is_loaded = true; 3262 assert(UseSignalChaining, "should enable signal-chaining"); 3263 } 3264 if (libjsig_is_loaded) { 3265 // Tell libjsig jvm is setting signal handlers 3266 (*begin_signal_setting)(); 3267 } 3268 3269 set_signal_handler(SIGSEGV, true); 3270 set_signal_handler(SIGPIPE, true); 3271 set_signal_handler(SIGBUS, true); 3272 set_signal_handler(SIGILL, true); 3273 set_signal_handler(SIGFPE, true); 3274 set_signal_handler(SIGXFSZ, true); 3275 3276#if defined(__APPLE__) 3277 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3278 // signals caught and handled by the JVM. To work around this, we reset the mach task 3279 // signal handler that's placed on our process by CrashReporter. This disables 3280 // CrashReporter-based reporting. 3281 // 3282 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3283 // on caught fatal signals. 3284 // 3285 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3286 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3287 // exception handling, while leaving the standard BSD signal handlers functional. 3288 kern_return_t kr; 3289 kr = task_set_exception_ports(mach_task_self(), 3290 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3291 MACH_PORT_NULL, 3292 EXCEPTION_STATE_IDENTITY, 3293 MACHINE_THREAD_STATE); 3294 3295 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3296#endif 3297 3298 if (libjsig_is_loaded) { 3299 // Tell libjsig jvm finishes setting signal handlers 3300 (*end_signal_setting)(); 3301 } 3302 3303 // We don't activate signal checker if libjsig is in place, we trust ourselves 3304 // and if UserSignalHandler is installed all bets are off 3305 if (CheckJNICalls) { 3306 if (libjsig_is_loaded) { 3307 if (PrintJNIResolving) { 3308 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3309 } 3310 check_signals = false; 3311 } 3312 if (AllowUserSignalHandlers) { 3313 if (PrintJNIResolving) { 3314 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3315 } 3316 check_signals = false; 3317 } 3318 } 3319 } 3320} 3321 3322 3323///// 3324// glibc on Bsd platform uses non-documented flag 3325// to indicate, that some special sort of signal 3326// trampoline is used. 3327// We will never set this flag, and we should 3328// ignore this flag in our diagnostic 3329#ifdef SIGNIFICANT_SIGNAL_MASK 3330#undef SIGNIFICANT_SIGNAL_MASK 3331#endif 3332#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3333 3334static const char* get_signal_handler_name(address handler, 3335 char* buf, int buflen) { 3336 int offset; 3337 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3338 if (found) { 3339 // skip directory names 3340 const char *p1, *p2; 3341 p1 = buf; 3342 size_t len = strlen(os::file_separator()); 3343 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3344 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3345 } else { 3346 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3347 } 3348 return buf; 3349} 3350 3351static void print_signal_handler(outputStream* st, int sig, 3352 char* buf, size_t buflen) { 3353 struct sigaction sa; 3354 3355 sigaction(sig, NULL, &sa); 3356 3357 // See comment for SIGNIFICANT_SIGNAL_MASK define 3358 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3359 3360 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3361 3362 address handler = (sa.sa_flags & SA_SIGINFO) 3363 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3364 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3365 3366 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3367 st->print("SIG_DFL"); 3368 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3369 st->print("SIG_IGN"); 3370 } else { 3371 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3372 } 3373 3374 st->print(", sa_mask[0]="); 3375 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3376 3377 address rh = VMError::get_resetted_sighandler(sig); 3378 // May be, handler was resetted by VMError? 3379 if(rh != NULL) { 3380 handler = rh; 3381 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3382 } 3383 3384 st->print(", sa_flags="); 3385 os::Posix::print_sa_flags(st, sa.sa_flags); 3386 3387 // Check: is it our handler? 3388 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3389 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3390 // It is our signal handler 3391 // check for flags, reset system-used one! 3392 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3393 st->print( 3394 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3395 os::Bsd::get_our_sigflags(sig)); 3396 } 3397 } 3398 st->cr(); 3399} 3400 3401 3402#define DO_SIGNAL_CHECK(sig) \ 3403 if (!sigismember(&check_signal_done, sig)) \ 3404 os::Bsd::check_signal_handler(sig) 3405 3406// This method is a periodic task to check for misbehaving JNI applications 3407// under CheckJNI, we can add any periodic checks here 3408 3409void os::run_periodic_checks() { 3410 3411 if (check_signals == false) return; 3412 3413 // SEGV and BUS if overridden could potentially prevent 3414 // generation of hs*.log in the event of a crash, debugging 3415 // such a case can be very challenging, so we absolutely 3416 // check the following for a good measure: 3417 DO_SIGNAL_CHECK(SIGSEGV); 3418 DO_SIGNAL_CHECK(SIGILL); 3419 DO_SIGNAL_CHECK(SIGFPE); 3420 DO_SIGNAL_CHECK(SIGBUS); 3421 DO_SIGNAL_CHECK(SIGPIPE); 3422 DO_SIGNAL_CHECK(SIGXFSZ); 3423 3424 3425 // ReduceSignalUsage allows the user to override these handlers 3426 // see comments at the very top and jvm_solaris.h 3427 if (!ReduceSignalUsage) { 3428 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3429 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3430 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3431 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3432 } 3433 3434 DO_SIGNAL_CHECK(SR_signum); 3435 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3436} 3437 3438typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3439 3440static os_sigaction_t os_sigaction = NULL; 3441 3442void os::Bsd::check_signal_handler(int sig) { 3443 char buf[O_BUFLEN]; 3444 address jvmHandler = NULL; 3445 3446 3447 struct sigaction act; 3448 if (os_sigaction == NULL) { 3449 // only trust the default sigaction, in case it has been interposed 3450 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3451 if (os_sigaction == NULL) return; 3452 } 3453 3454 os_sigaction(sig, (struct sigaction*)NULL, &act); 3455 3456 3457 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3458 3459 address thisHandler = (act.sa_flags & SA_SIGINFO) 3460 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3461 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 3462 3463 3464 switch(sig) { 3465 case SIGSEGV: 3466 case SIGBUS: 3467 case SIGFPE: 3468 case SIGPIPE: 3469 case SIGILL: 3470 case SIGXFSZ: 3471 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3472 break; 3473 3474 case SHUTDOWN1_SIGNAL: 3475 case SHUTDOWN2_SIGNAL: 3476 case SHUTDOWN3_SIGNAL: 3477 case BREAK_SIGNAL: 3478 jvmHandler = (address)user_handler(); 3479 break; 3480 3481 case INTERRUPT_SIGNAL: 3482 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3483 break; 3484 3485 default: 3486 if (sig == SR_signum) { 3487 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3488 } else { 3489 return; 3490 } 3491 break; 3492 } 3493 3494 if (thisHandler != jvmHandler) { 3495 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3496 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3497 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3498 // No need to check this sig any longer 3499 sigaddset(&check_signal_done, sig); 3500 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3501 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3502 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3503 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3504 // No need to check this sig any longer 3505 sigaddset(&check_signal_done, sig); 3506 } 3507 3508 // Dump all the signal 3509 if (sigismember(&check_signal_done, sig)) { 3510 print_signal_handlers(tty, buf, O_BUFLEN); 3511 } 3512} 3513 3514extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3515 3516extern bool signal_name(int signo, char* buf, size_t len); 3517 3518const char* os::exception_name(int exception_code, char* buf, size_t size) { 3519 if (0 < exception_code && exception_code <= SIGRTMAX) { 3520 // signal 3521 if (!signal_name(exception_code, buf, size)) { 3522 jio_snprintf(buf, size, "SIG%d", exception_code); 3523 } 3524 return buf; 3525 } else { 3526 return NULL; 3527 } 3528} 3529 3530// this is called _before_ the most of global arguments have been parsed 3531void os::init(void) { 3532 char dummy; /* used to get a guess on initial stack address */ 3533// first_hrtime = gethrtime(); 3534 3535 // With BsdThreads the JavaMain thread pid (primordial thread) 3536 // is different than the pid of the java launcher thread. 3537 // So, on Bsd, the launcher thread pid is passed to the VM 3538 // via the sun.java.launcher.pid property. 3539 // Use this property instead of getpid() if it was correctly passed. 3540 // See bug 6351349. 3541 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3542 3543 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3544 3545 clock_tics_per_sec = CLK_TCK; 3546 3547 init_random(1234567); 3548 3549 ThreadCritical::initialize(); 3550 3551 Bsd::set_page_size(getpagesize()); 3552 if (Bsd::page_size() == -1) { 3553 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3554 strerror(errno))); 3555 } 3556 init_page_sizes((size_t) Bsd::page_size()); 3557 3558 Bsd::initialize_system_info(); 3559 3560 // main_thread points to the aboriginal thread 3561 Bsd::_main_thread = pthread_self(); 3562 3563 Bsd::clock_init(); 3564 initial_time_count = javaTimeNanos(); 3565 3566#ifdef __APPLE__ 3567 // XXXDARWIN 3568 // Work around the unaligned VM callbacks in hotspot's 3569 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3570 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3571 // alignment when doing symbol lookup. To work around this, we force early 3572 // binding of all symbols now, thus binding when alignment is known-good. 3573 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3574#endif 3575} 3576 3577// To install functions for atexit system call 3578extern "C" { 3579 static void perfMemory_exit_helper() { 3580 perfMemory_exit(); 3581 } 3582} 3583 3584// this is called _after_ the global arguments have been parsed 3585jint os::init_2(void) 3586{ 3587 // Allocate a single page and mark it as readable for safepoint polling 3588 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3589 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 3590 3591 os::set_polling_page( polling_page ); 3592 3593#ifndef PRODUCT 3594 if(Verbose && PrintMiscellaneous) 3595 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3596#endif 3597 3598 if (!UseMembar) { 3599 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3600 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3601 os::set_memory_serialize_page( mem_serialize_page ); 3602 3603#ifndef PRODUCT 3604 if(Verbose && PrintMiscellaneous) 3605 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3606#endif 3607 } 3608 3609 // initialize suspend/resume support - must do this before signal_sets_init() 3610 if (SR_initialize() != 0) { 3611 perror("SR_initialize failed"); 3612 return JNI_ERR; 3613 } 3614 3615 Bsd::signal_sets_init(); 3616 Bsd::install_signal_handlers(); 3617 3618 // Check minimum allowable stack size for thread creation and to initialize 3619 // the java system classes, including StackOverflowError - depends on page 3620 // size. Add a page for compiler2 recursion in main thread. 3621 // Add in 2*BytesPerWord times page size to account for VM stack during 3622 // class initialization depending on 32 or 64 bit VM. 3623 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3624 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3625 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3626 3627 size_t threadStackSizeInBytes = ThreadStackSize * K; 3628 if (threadStackSizeInBytes != 0 && 3629 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3630 tty->print_cr("\nThe stack size specified is too small, " 3631 "Specify at least %dk", 3632 os::Bsd::min_stack_allowed/ K); 3633 return JNI_ERR; 3634 } 3635 3636 // Make the stack size a multiple of the page size so that 3637 // the yellow/red zones can be guarded. 3638 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3639 vm_page_size())); 3640 3641 if (MaxFDLimit) { 3642 // set the number of file descriptors to max. print out error 3643 // if getrlimit/setrlimit fails but continue regardless. 3644 struct rlimit nbr_files; 3645 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3646 if (status != 0) { 3647 if (PrintMiscellaneous && (Verbose || WizardMode)) 3648 perror("os::init_2 getrlimit failed"); 3649 } else { 3650 nbr_files.rlim_cur = nbr_files.rlim_max; 3651 3652#ifdef __APPLE__ 3653 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3654 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3655 // be used instead 3656 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3657#endif 3658 3659 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3660 if (status != 0) { 3661 if (PrintMiscellaneous && (Verbose || WizardMode)) 3662 perror("os::init_2 setrlimit failed"); 3663 } 3664 } 3665 } 3666 3667 // at-exit methods are called in the reverse order of their registration. 3668 // atexit functions are called on return from main or as a result of a 3669 // call to exit(3C). There can be only 32 of these functions registered 3670 // and atexit() does not set errno. 3671 3672 if (PerfAllowAtExitRegistration) { 3673 // only register atexit functions if PerfAllowAtExitRegistration is set. 3674 // atexit functions can be delayed until process exit time, which 3675 // can be problematic for embedded VM situations. Embedded VMs should 3676 // call DestroyJavaVM() to assure that VM resources are released. 3677 3678 // note: perfMemory_exit_helper atexit function may be removed in 3679 // the future if the appropriate cleanup code can be added to the 3680 // VM_Exit VMOperation's doit method. 3681 if (atexit(perfMemory_exit_helper) != 0) { 3682 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3683 } 3684 } 3685 3686 // initialize thread priority policy 3687 prio_init(); 3688 3689#ifdef __APPLE__ 3690 // dynamically link to objective c gc registration 3691 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3692 if (handleLibObjc != NULL) { 3693 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3694 } 3695#endif 3696 3697 return JNI_OK; 3698} 3699 3700// this is called at the end of vm_initialization 3701void os::init_3(void) { } 3702 3703// Mark the polling page as unreadable 3704void os::make_polling_page_unreadable(void) { 3705 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 3706 fatal("Could not disable polling page"); 3707}; 3708 3709// Mark the polling page as readable 3710void os::make_polling_page_readable(void) { 3711 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3712 fatal("Could not enable polling page"); 3713 } 3714}; 3715 3716int os::active_processor_count() { 3717 return _processor_count; 3718} 3719 3720void os::set_native_thread_name(const char *name) { 3721#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3722 // This is only supported in Snow Leopard and beyond 3723 if (name != NULL) { 3724 // Add a "Java: " prefix to the name 3725 char buf[MAXTHREADNAMESIZE]; 3726 snprintf(buf, sizeof(buf), "Java: %s", name); 3727 pthread_setname_np(buf); 3728 } 3729#endif 3730} 3731 3732bool os::distribute_processes(uint length, uint* distribution) { 3733 // Not yet implemented. 3734 return false; 3735} 3736 3737bool os::bind_to_processor(uint processor_id) { 3738 // Not yet implemented. 3739 return false; 3740} 3741 3742void os::SuspendedThreadTask::internal_do_task() { 3743 if (do_suspend(_thread->osthread())) { 3744 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3745 do_task(context); 3746 do_resume(_thread->osthread()); 3747 } 3748} 3749 3750/// 3751class PcFetcher : public os::SuspendedThreadTask { 3752public: 3753 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3754 ExtendedPC result(); 3755protected: 3756 void do_task(const os::SuspendedThreadTaskContext& context); 3757private: 3758 ExtendedPC _epc; 3759}; 3760 3761ExtendedPC PcFetcher::result() { 3762 guarantee(is_done(), "task is not done yet."); 3763 return _epc; 3764} 3765 3766void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3767 Thread* thread = context.thread(); 3768 OSThread* osthread = thread->osthread(); 3769 if (osthread->ucontext() != NULL) { 3770 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3771 } else { 3772 // NULL context is unexpected, double-check this is the VMThread 3773 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3774 } 3775} 3776 3777// Suspends the target using the signal mechanism and then grabs the PC before 3778// resuming the target. Used by the flat-profiler only 3779ExtendedPC os::get_thread_pc(Thread* thread) { 3780 // Make sure that it is called by the watcher for the VMThread 3781 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3782 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3783 3784 PcFetcher fetcher(thread); 3785 fetcher.run(); 3786 return fetcher.result(); 3787} 3788 3789int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3790{ 3791 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3792} 3793 3794//////////////////////////////////////////////////////////////////////////////// 3795// debug support 3796 3797bool os::find(address addr, outputStream* st) { 3798 Dl_info dlinfo; 3799 memset(&dlinfo, 0, sizeof(dlinfo)); 3800 if (dladdr(addr, &dlinfo) != 0) { 3801 st->print(PTR_FORMAT ": ", addr); 3802 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3803 st->print("%s+%#x", dlinfo.dli_sname, 3804 addr - (intptr_t)dlinfo.dli_saddr); 3805 } else if (dlinfo.dli_fbase != NULL) { 3806 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3807 } else { 3808 st->print("<absolute address>"); 3809 } 3810 if (dlinfo.dli_fname != NULL) { 3811 st->print(" in %s", dlinfo.dli_fname); 3812 } 3813 if (dlinfo.dli_fbase != NULL) { 3814 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3815 } 3816 st->cr(); 3817 3818 if (Verbose) { 3819 // decode some bytes around the PC 3820 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3821 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3822 address lowest = (address) dlinfo.dli_sname; 3823 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3824 if (begin < lowest) begin = lowest; 3825 Dl_info dlinfo2; 3826 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3827 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3828 end = (address) dlinfo2.dli_saddr; 3829 Disassembler::decode(begin, end, st); 3830 } 3831 return true; 3832 } 3833 return false; 3834} 3835 3836//////////////////////////////////////////////////////////////////////////////// 3837// misc 3838 3839// This does not do anything on Bsd. This is basically a hook for being 3840// able to use structured exception handling (thread-local exception filters) 3841// on, e.g., Win32. 3842void 3843os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3844 JavaCallArguments* args, Thread* thread) { 3845 f(value, method, args, thread); 3846} 3847 3848void os::print_statistics() { 3849} 3850 3851int os::message_box(const char* title, const char* message) { 3852 int i; 3853 fdStream err(defaultStream::error_fd()); 3854 for (i = 0; i < 78; i++) err.print_raw("="); 3855 err.cr(); 3856 err.print_raw_cr(title); 3857 for (i = 0; i < 78; i++) err.print_raw("-"); 3858 err.cr(); 3859 err.print_raw_cr(message); 3860 for (i = 0; i < 78; i++) err.print_raw("="); 3861 err.cr(); 3862 3863 char buf[16]; 3864 // Prevent process from exiting upon "read error" without consuming all CPU 3865 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3866 3867 return buf[0] == 'y' || buf[0] == 'Y'; 3868} 3869 3870int os::stat(const char *path, struct stat *sbuf) { 3871 char pathbuf[MAX_PATH]; 3872 if (strlen(path) > MAX_PATH - 1) { 3873 errno = ENAMETOOLONG; 3874 return -1; 3875 } 3876 os::native_path(strcpy(pathbuf, path)); 3877 return ::stat(pathbuf, sbuf); 3878} 3879 3880bool os::check_heap(bool force) { 3881 return true; 3882} 3883 3884int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 3885 return ::vsnprintf(buf, count, format, args); 3886} 3887 3888// Is a (classpath) directory empty? 3889bool os::dir_is_empty(const char* path) { 3890 DIR *dir = NULL; 3891 struct dirent *ptr; 3892 3893 dir = opendir(path); 3894 if (dir == NULL) return true; 3895 3896 /* Scan the directory */ 3897 bool result = true; 3898 char buf[sizeof(struct dirent) + MAX_PATH]; 3899 while (result && (ptr = ::readdir(dir)) != NULL) { 3900 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3901 result = false; 3902 } 3903 } 3904 closedir(dir); 3905 return result; 3906} 3907 3908// This code originates from JDK's sysOpen and open64_w 3909// from src/solaris/hpi/src/system_md.c 3910 3911#ifndef O_DELETE 3912#define O_DELETE 0x10000 3913#endif 3914 3915// Open a file. Unlink the file immediately after open returns 3916// if the specified oflag has the O_DELETE flag set. 3917// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3918 3919int os::open(const char *path, int oflag, int mode) { 3920 3921 if (strlen(path) > MAX_PATH - 1) { 3922 errno = ENAMETOOLONG; 3923 return -1; 3924 } 3925 int fd; 3926 int o_delete = (oflag & O_DELETE); 3927 oflag = oflag & ~O_DELETE; 3928 3929 fd = ::open(path, oflag, mode); 3930 if (fd == -1) return -1; 3931 3932 //If the open succeeded, the file might still be a directory 3933 { 3934 struct stat buf; 3935 int ret = ::fstat(fd, &buf); 3936 int st_mode = buf.st_mode; 3937 3938 if (ret != -1) { 3939 if ((st_mode & S_IFMT) == S_IFDIR) { 3940 errno = EISDIR; 3941 ::close(fd); 3942 return -1; 3943 } 3944 } else { 3945 ::close(fd); 3946 return -1; 3947 } 3948 } 3949 3950 /* 3951 * All file descriptors that are opened in the JVM and not 3952 * specifically destined for a subprocess should have the 3953 * close-on-exec flag set. If we don't set it, then careless 3rd 3954 * party native code might fork and exec without closing all 3955 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3956 * UNIXProcess.c), and this in turn might: 3957 * 3958 * - cause end-of-file to fail to be detected on some file 3959 * descriptors, resulting in mysterious hangs, or 3960 * 3961 * - might cause an fopen in the subprocess to fail on a system 3962 * suffering from bug 1085341. 3963 * 3964 * (Yes, the default setting of the close-on-exec flag is a Unix 3965 * design flaw) 3966 * 3967 * See: 3968 * 1085341: 32-bit stdio routines should support file descriptors >255 3969 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3970 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3971 */ 3972#ifdef FD_CLOEXEC 3973 { 3974 int flags = ::fcntl(fd, F_GETFD); 3975 if (flags != -1) 3976 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3977 } 3978#endif 3979 3980 if (o_delete != 0) { 3981 ::unlink(path); 3982 } 3983 return fd; 3984} 3985 3986 3987// create binary file, rewriting existing file if required 3988int os::create_binary_file(const char* path, bool rewrite_existing) { 3989 int oflags = O_WRONLY | O_CREAT; 3990 if (!rewrite_existing) { 3991 oflags |= O_EXCL; 3992 } 3993 return ::open(path, oflags, S_IREAD | S_IWRITE); 3994} 3995 3996// return current position of file pointer 3997jlong os::current_file_offset(int fd) { 3998 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3999} 4000 4001// move file pointer to the specified offset 4002jlong os::seek_to_file_offset(int fd, jlong offset) { 4003 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 4004} 4005 4006// This code originates from JDK's sysAvailable 4007// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 4008 4009int os::available(int fd, jlong *bytes) { 4010 jlong cur, end; 4011 int mode; 4012 struct stat buf; 4013 4014 if (::fstat(fd, &buf) >= 0) { 4015 mode = buf.st_mode; 4016 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 4017 /* 4018 * XXX: is the following call interruptible? If so, this might 4019 * need to go through the INTERRUPT_IO() wrapper as for other 4020 * blocking, interruptible calls in this file. 4021 */ 4022 int n; 4023 if (::ioctl(fd, FIONREAD, &n) >= 0) { 4024 *bytes = n; 4025 return 1; 4026 } 4027 } 4028 } 4029 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 4030 return 0; 4031 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 4032 return 0; 4033 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 4034 return 0; 4035 } 4036 *bytes = end - cur; 4037 return 1; 4038} 4039 4040int os::socket_available(int fd, jint *pbytes) { 4041 if (fd < 0) 4042 return OS_OK; 4043 4044 int ret; 4045 4046 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 4047 4048 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 4049 // is expected to return 0 on failure and 1 on success to the jdk. 4050 4051 return (ret == OS_ERR) ? 0 : 1; 4052} 4053 4054// Map a block of memory. 4055char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 4056 char *addr, size_t bytes, bool read_only, 4057 bool allow_exec) { 4058 int prot; 4059 int flags; 4060 4061 if (read_only) { 4062 prot = PROT_READ; 4063 flags = MAP_SHARED; 4064 } else { 4065 prot = PROT_READ | PROT_WRITE; 4066 flags = MAP_PRIVATE; 4067 } 4068 4069 if (allow_exec) { 4070 prot |= PROT_EXEC; 4071 } 4072 4073 if (addr != NULL) { 4074 flags |= MAP_FIXED; 4075 } 4076 4077 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4078 fd, file_offset); 4079 if (mapped_address == MAP_FAILED) { 4080 return NULL; 4081 } 4082 return mapped_address; 4083} 4084 4085 4086// Remap a block of memory. 4087char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4088 char *addr, size_t bytes, bool read_only, 4089 bool allow_exec) { 4090 // same as map_memory() on this OS 4091 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4092 allow_exec); 4093} 4094 4095 4096// Unmap a block of memory. 4097bool os::pd_unmap_memory(char* addr, size_t bytes) { 4098 return munmap(addr, bytes) == 0; 4099} 4100 4101// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4102// are used by JVM M&M and JVMTI to get user+sys or user CPU time 4103// of a thread. 4104// 4105// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4106// the fast estimate available on the platform. 4107 4108jlong os::current_thread_cpu_time() { 4109#ifdef __APPLE__ 4110 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4111#else 4112 Unimplemented(); 4113 return 0; 4114#endif 4115} 4116 4117jlong os::thread_cpu_time(Thread* thread) { 4118#ifdef __APPLE__ 4119 return os::thread_cpu_time(thread, true /* user + sys */); 4120#else 4121 Unimplemented(); 4122 return 0; 4123#endif 4124} 4125 4126jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4127#ifdef __APPLE__ 4128 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4129#else 4130 Unimplemented(); 4131 return 0; 4132#endif 4133} 4134 4135jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4136#ifdef __APPLE__ 4137 struct thread_basic_info tinfo; 4138 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4139 kern_return_t kr; 4140 thread_t mach_thread; 4141 4142 mach_thread = thread->osthread()->thread_id(); 4143 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4144 if (kr != KERN_SUCCESS) 4145 return -1; 4146 4147 if (user_sys_cpu_time) { 4148 jlong nanos; 4149 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4150 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4151 return nanos; 4152 } else { 4153 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4154 } 4155#else 4156 Unimplemented(); 4157 return 0; 4158#endif 4159} 4160 4161 4162void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4163 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4164 info_ptr->may_skip_backward = false; // elapsed time not wall time 4165 info_ptr->may_skip_forward = false; // elapsed time not wall time 4166 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4167} 4168 4169void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4170 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4171 info_ptr->may_skip_backward = false; // elapsed time not wall time 4172 info_ptr->may_skip_forward = false; // elapsed time not wall time 4173 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4174} 4175 4176bool os::is_thread_cpu_time_supported() { 4177#ifdef __APPLE__ 4178 return true; 4179#else 4180 return false; 4181#endif 4182} 4183 4184// System loadavg support. Returns -1 if load average cannot be obtained. 4185// Bsd doesn't yet have a (official) notion of processor sets, 4186// so just return the system wide load average. 4187int os::loadavg(double loadavg[], int nelem) { 4188 return ::getloadavg(loadavg, nelem); 4189} 4190 4191void os::pause() { 4192 char filename[MAX_PATH]; 4193 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4194 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4195 } else { 4196 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4197 } 4198 4199 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4200 if (fd != -1) { 4201 struct stat buf; 4202 ::close(fd); 4203 while (::stat(filename, &buf) == 0) { 4204 (void)::poll(NULL, 0, 100); 4205 } 4206 } else { 4207 jio_fprintf(stderr, 4208 "Could not open pause file '%s', continuing immediately.\n", filename); 4209 } 4210} 4211 4212 4213// Refer to the comments in os_solaris.cpp park-unpark. 4214// 4215// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4216// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4217// For specifics regarding the bug see GLIBC BUGID 261237 : 4218// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4219// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4220// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4221// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4222// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4223// and monitorenter when we're using 1-0 locking. All those operations may result in 4224// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4225// of libpthread avoids the problem, but isn't practical. 4226// 4227// Possible remedies: 4228// 4229// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4230// This is palliative and probabilistic, however. If the thread is preempted 4231// between the call to compute_abstime() and pthread_cond_timedwait(), more 4232// than the minimum period may have passed, and the abstime may be stale (in the 4233// past) resultin in a hang. Using this technique reduces the odds of a hang 4234// but the JVM is still vulnerable, particularly on heavily loaded systems. 4235// 4236// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4237// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4238// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4239// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4240// thread. 4241// 4242// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4243// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4244// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4245// This also works well. In fact it avoids kernel-level scalability impediments 4246// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4247// timers in a graceful fashion. 4248// 4249// 4. When the abstime value is in the past it appears that control returns 4250// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4251// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4252// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4253// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4254// It may be possible to avoid reinitialization by checking the return 4255// value from pthread_cond_timedwait(). In addition to reinitializing the 4256// condvar we must establish the invariant that cond_signal() is only called 4257// within critical sections protected by the adjunct mutex. This prevents 4258// cond_signal() from "seeing" a condvar that's in the midst of being 4259// reinitialized or that is corrupt. Sadly, this invariant obviates the 4260// desirable signal-after-unlock optimization that avoids futile context switching. 4261// 4262// I'm also concerned that some versions of NTPL might allocate an auxilliary 4263// structure when a condvar is used or initialized. cond_destroy() would 4264// release the helper structure. Our reinitialize-after-timedwait fix 4265// put excessive stress on malloc/free and locks protecting the c-heap. 4266// 4267// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4268// It may be possible to refine (4) by checking the kernel and NTPL verisons 4269// and only enabling the work-around for vulnerable environments. 4270 4271// utility to compute the abstime argument to timedwait: 4272// millis is the relative timeout time 4273// abstime will be the absolute timeout time 4274// TODO: replace compute_abstime() with unpackTime() 4275 4276static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4277 if (millis < 0) millis = 0; 4278 struct timeval now; 4279 int status = gettimeofday(&now, NULL); 4280 assert(status == 0, "gettimeofday"); 4281 jlong seconds = millis / 1000; 4282 millis %= 1000; 4283 if (seconds > 50000000) { // see man cond_timedwait(3T) 4284 seconds = 50000000; 4285 } 4286 abstime->tv_sec = now.tv_sec + seconds; 4287 long usec = now.tv_usec + millis * 1000; 4288 if (usec >= 1000000) { 4289 abstime->tv_sec += 1; 4290 usec -= 1000000; 4291 } 4292 abstime->tv_nsec = usec * 1000; 4293 return abstime; 4294} 4295 4296 4297// Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 4298// Conceptually TryPark() should be equivalent to park(0). 4299 4300int os::PlatformEvent::TryPark() { 4301 for (;;) { 4302 const int v = _Event ; 4303 guarantee ((v == 0) || (v == 1), "invariant") ; 4304 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 4305 } 4306} 4307 4308void os::PlatformEvent::park() { // AKA "down()" 4309 // Invariant: Only the thread associated with the Event/PlatformEvent 4310 // may call park(). 4311 // TODO: assert that _Assoc != NULL or _Assoc == Self 4312 int v ; 4313 for (;;) { 4314 v = _Event ; 4315 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4316 } 4317 guarantee (v >= 0, "invariant") ; 4318 if (v == 0) { 4319 // Do this the hard way by blocking ... 4320 int status = pthread_mutex_lock(_mutex); 4321 assert_status(status == 0, status, "mutex_lock"); 4322 guarantee (_nParked == 0, "invariant") ; 4323 ++ _nParked ; 4324 while (_Event < 0) { 4325 status = pthread_cond_wait(_cond, _mutex); 4326 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4327 // Treat this the same as if the wait was interrupted 4328 if (status == ETIMEDOUT) { status = EINTR; } 4329 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4330 } 4331 -- _nParked ; 4332 4333 _Event = 0 ; 4334 status = pthread_mutex_unlock(_mutex); 4335 assert_status(status == 0, status, "mutex_unlock"); 4336 // Paranoia to ensure our locked and lock-free paths interact 4337 // correctly with each other. 4338 OrderAccess::fence(); 4339 } 4340 guarantee (_Event >= 0, "invariant") ; 4341} 4342 4343int os::PlatformEvent::park(jlong millis) { 4344 guarantee (_nParked == 0, "invariant") ; 4345 4346 int v ; 4347 for (;;) { 4348 v = _Event ; 4349 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4350 } 4351 guarantee (v >= 0, "invariant") ; 4352 if (v != 0) return OS_OK ; 4353 4354 // We do this the hard way, by blocking the thread. 4355 // Consider enforcing a minimum timeout value. 4356 struct timespec abst; 4357 compute_abstime(&abst, millis); 4358 4359 int ret = OS_TIMEOUT; 4360 int status = pthread_mutex_lock(_mutex); 4361 assert_status(status == 0, status, "mutex_lock"); 4362 guarantee (_nParked == 0, "invariant") ; 4363 ++_nParked ; 4364 4365 // Object.wait(timo) will return because of 4366 // (a) notification 4367 // (b) timeout 4368 // (c) thread.interrupt 4369 // 4370 // Thread.interrupt and object.notify{All} both call Event::set. 4371 // That is, we treat thread.interrupt as a special case of notification. 4372 // The underlying Solaris implementation, cond_timedwait, admits 4373 // spurious/premature wakeups, but the JLS/JVM spec prevents the 4374 // JVM from making those visible to Java code. As such, we must 4375 // filter out spurious wakeups. We assume all ETIME returns are valid. 4376 // 4377 // TODO: properly differentiate simultaneous notify+interrupt. 4378 // In that case, we should propagate the notify to another waiter. 4379 4380 while (_Event < 0) { 4381 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4382 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4383 pthread_cond_destroy (_cond); 4384 pthread_cond_init (_cond, NULL) ; 4385 } 4386 assert_status(status == 0 || status == EINTR || 4387 status == ETIMEDOUT, 4388 status, "cond_timedwait"); 4389 if (!FilterSpuriousWakeups) break ; // previous semantics 4390 if (status == ETIMEDOUT) break ; 4391 // We consume and ignore EINTR and spurious wakeups. 4392 } 4393 --_nParked ; 4394 if (_Event >= 0) { 4395 ret = OS_OK; 4396 } 4397 _Event = 0 ; 4398 status = pthread_mutex_unlock(_mutex); 4399 assert_status(status == 0, status, "mutex_unlock"); 4400 assert (_nParked == 0, "invariant") ; 4401 // Paranoia to ensure our locked and lock-free paths interact 4402 // correctly with each other. 4403 OrderAccess::fence(); 4404 return ret; 4405} 4406 4407void os::PlatformEvent::unpark() { 4408 // Transitions for _Event: 4409 // 0 :=> 1 4410 // 1 :=> 1 4411 // -1 :=> either 0 or 1; must signal target thread 4412 // That is, we can safely transition _Event from -1 to either 4413 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back 4414 // unpark() calls. 4415 // See also: "Semaphores in Plan 9" by Mullender & Cox 4416 // 4417 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4418 // that it will take two back-to-back park() calls for the owning 4419 // thread to block. This has the benefit of forcing a spurious return 4420 // from the first park() call after an unpark() call which will help 4421 // shake out uses of park() and unpark() without condition variables. 4422 4423 if (Atomic::xchg(1, &_Event) >= 0) return; 4424 4425 // Wait for the thread associated with the event to vacate 4426 int status = pthread_mutex_lock(_mutex); 4427 assert_status(status == 0, status, "mutex_lock"); 4428 int AnyWaiters = _nParked; 4429 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4430 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4431 AnyWaiters = 0; 4432 pthread_cond_signal(_cond); 4433 } 4434 status = pthread_mutex_unlock(_mutex); 4435 assert_status(status == 0, status, "mutex_unlock"); 4436 if (AnyWaiters != 0) { 4437 status = pthread_cond_signal(_cond); 4438 assert_status(status == 0, status, "cond_signal"); 4439 } 4440 4441 // Note that we signal() _after dropping the lock for "immortal" Events. 4442 // This is safe and avoids a common class of futile wakeups. In rare 4443 // circumstances this can cause a thread to return prematurely from 4444 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4445 // simply re-test the condition and re-park itself. 4446} 4447 4448 4449// JSR166 4450// ------------------------------------------------------- 4451 4452/* 4453 * The solaris and bsd implementations of park/unpark are fairly 4454 * conservative for now, but can be improved. They currently use a 4455 * mutex/condvar pair, plus a a count. 4456 * Park decrements count if > 0, else does a condvar wait. Unpark 4457 * sets count to 1 and signals condvar. Only one thread ever waits 4458 * on the condvar. Contention seen when trying to park implies that someone 4459 * is unparking you, so don't wait. And spurious returns are fine, so there 4460 * is no need to track notifications. 4461 */ 4462 4463#define MAX_SECS 100000000 4464/* 4465 * This code is common to bsd and solaris and will be moved to a 4466 * common place in dolphin. 4467 * 4468 * The passed in time value is either a relative time in nanoseconds 4469 * or an absolute time in milliseconds. Either way it has to be unpacked 4470 * into suitable seconds and nanoseconds components and stored in the 4471 * given timespec structure. 4472 * Given time is a 64-bit value and the time_t used in the timespec is only 4473 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4474 * overflow if times way in the future are given. Further on Solaris versions 4475 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4476 * number of seconds, in abstime, is less than current_time + 100,000,000. 4477 * As it will be 28 years before "now + 100000000" will overflow we can 4478 * ignore overflow and just impose a hard-limit on seconds using the value 4479 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4480 * years from "now". 4481 */ 4482 4483static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4484 assert (time > 0, "convertTime"); 4485 4486 struct timeval now; 4487 int status = gettimeofday(&now, NULL); 4488 assert(status == 0, "gettimeofday"); 4489 4490 time_t max_secs = now.tv_sec + MAX_SECS; 4491 4492 if (isAbsolute) { 4493 jlong secs = time / 1000; 4494 if (secs > max_secs) { 4495 absTime->tv_sec = max_secs; 4496 } 4497 else { 4498 absTime->tv_sec = secs; 4499 } 4500 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4501 } 4502 else { 4503 jlong secs = time / NANOSECS_PER_SEC; 4504 if (secs >= MAX_SECS) { 4505 absTime->tv_sec = max_secs; 4506 absTime->tv_nsec = 0; 4507 } 4508 else { 4509 absTime->tv_sec = now.tv_sec + secs; 4510 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4511 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4512 absTime->tv_nsec -= NANOSECS_PER_SEC; 4513 ++absTime->tv_sec; // note: this must be <= max_secs 4514 } 4515 } 4516 } 4517 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4518 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4519 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4520 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4521} 4522 4523void Parker::park(bool isAbsolute, jlong time) { 4524 // Ideally we'd do something useful while spinning, such 4525 // as calling unpackTime(). 4526 4527 // Optional fast-path check: 4528 // Return immediately if a permit is available. 4529 // We depend on Atomic::xchg() having full barrier semantics 4530 // since we are doing a lock-free update to _counter. 4531 if (Atomic::xchg(0, &_counter) > 0) return; 4532 4533 Thread* thread = Thread::current(); 4534 assert(thread->is_Java_thread(), "Must be JavaThread"); 4535 JavaThread *jt = (JavaThread *)thread; 4536 4537 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4538 // Check interrupt before trying to wait 4539 if (Thread::is_interrupted(thread, false)) { 4540 return; 4541 } 4542 4543 // Next, demultiplex/decode time arguments 4544 struct timespec absTime; 4545 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 4546 return; 4547 } 4548 if (time > 0) { 4549 unpackTime(&absTime, isAbsolute, time); 4550 } 4551 4552 4553 // Enter safepoint region 4554 // Beware of deadlocks such as 6317397. 4555 // The per-thread Parker:: mutex is a classic leaf-lock. 4556 // In particular a thread must never block on the Threads_lock while 4557 // holding the Parker:: mutex. If safepoints are pending both the 4558 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4559 ThreadBlockInVM tbivm(jt); 4560 4561 // Don't wait if cannot get lock since interference arises from 4562 // unblocking. Also. check interrupt before trying wait 4563 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4564 return; 4565 } 4566 4567 int status ; 4568 if (_counter > 0) { // no wait needed 4569 _counter = 0; 4570 status = pthread_mutex_unlock(_mutex); 4571 assert (status == 0, "invariant") ; 4572 // Paranoia to ensure our locked and lock-free paths interact 4573 // correctly with each other and Java-level accesses. 4574 OrderAccess::fence(); 4575 return; 4576 } 4577 4578#ifdef ASSERT 4579 // Don't catch signals while blocked; let the running threads have the signals. 4580 // (This allows a debugger to break into the running thread.) 4581 sigset_t oldsigs; 4582 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4583 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4584#endif 4585 4586 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4587 jt->set_suspend_equivalent(); 4588 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4589 4590 if (time == 0) { 4591 status = pthread_cond_wait (_cond, _mutex) ; 4592 } else { 4593 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 4594 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4595 pthread_cond_destroy (_cond) ; 4596 pthread_cond_init (_cond, NULL); 4597 } 4598 } 4599 assert_status(status == 0 || status == EINTR || 4600 status == ETIMEDOUT, 4601 status, "cond_timedwait"); 4602 4603#ifdef ASSERT 4604 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4605#endif 4606 4607 _counter = 0 ; 4608 status = pthread_mutex_unlock(_mutex) ; 4609 assert_status(status == 0, status, "invariant") ; 4610 // Paranoia to ensure our locked and lock-free paths interact 4611 // correctly with each other and Java-level accesses. 4612 OrderAccess::fence(); 4613 4614 // If externally suspended while waiting, re-suspend 4615 if (jt->handle_special_suspend_equivalent_condition()) { 4616 jt->java_suspend_self(); 4617 } 4618} 4619 4620void Parker::unpark() { 4621 int s, status ; 4622 status = pthread_mutex_lock(_mutex); 4623 assert (status == 0, "invariant") ; 4624 s = _counter; 4625 _counter = 1; 4626 if (s < 1) { 4627 if (WorkAroundNPTLTimedWaitHang) { 4628 status = pthread_cond_signal (_cond) ; 4629 assert (status == 0, "invariant") ; 4630 status = pthread_mutex_unlock(_mutex); 4631 assert (status == 0, "invariant") ; 4632 } else { 4633 status = pthread_mutex_unlock(_mutex); 4634 assert (status == 0, "invariant") ; 4635 status = pthread_cond_signal (_cond) ; 4636 assert (status == 0, "invariant") ; 4637 } 4638 } else { 4639 pthread_mutex_unlock(_mutex); 4640 assert (status == 0, "invariant") ; 4641 } 4642} 4643 4644 4645/* Darwin has no "environ" in a dynamic library. */ 4646#ifdef __APPLE__ 4647#include <crt_externs.h> 4648#define environ (*_NSGetEnviron()) 4649#else 4650extern char** environ; 4651#endif 4652 4653// Run the specified command in a separate process. Return its exit value, 4654// or -1 on failure (e.g. can't fork a new process). 4655// Unlike system(), this function can be called from signal handler. It 4656// doesn't block SIGINT et al. 4657int os::fork_and_exec(char* cmd) { 4658 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4659 4660 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4661 // pthread_atfork handlers and reset pthread library. All we need is a 4662 // separate process to execve. Make a direct syscall to fork process. 4663 // On IA64 there's no fork syscall, we have to use fork() and hope for 4664 // the best... 4665 pid_t pid = fork(); 4666 4667 if (pid < 0) { 4668 // fork failed 4669 return -1; 4670 4671 } else if (pid == 0) { 4672 // child process 4673 4674 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4675 // first to kill every thread on the thread list. Because this list is 4676 // not reset by fork() (see notes above), execve() will instead kill 4677 // every thread in the parent process. We know this is the only thread 4678 // in the new process, so make a system call directly. 4679 // IA64 should use normal execve() from glibc to match the glibc fork() 4680 // above. 4681 execve("/bin/sh", (char* const*)argv, environ); 4682 4683 // execve failed 4684 _exit(-1); 4685 4686 } else { 4687 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4688 // care about the actual exit code, for now. 4689 4690 int status; 4691 4692 // Wait for the child process to exit. This returns immediately if 4693 // the child has already exited. */ 4694 while (waitpid(pid, &status, 0) < 0) { 4695 switch (errno) { 4696 case ECHILD: return 0; 4697 case EINTR: break; 4698 default: return -1; 4699 } 4700 } 4701 4702 if (WIFEXITED(status)) { 4703 // The child exited normally; get its exit code. 4704 return WEXITSTATUS(status); 4705 } else if (WIFSIGNALED(status)) { 4706 // The child exited because of a signal 4707 // The best value to return is 0x80 + signal number, 4708 // because that is what all Unix shells do, and because 4709 // it allows callers to distinguish between process exit and 4710 // process death by signal. 4711 return 0x80 + WTERMSIG(status); 4712 } else { 4713 // Unknown exit code; pass it through 4714 return status; 4715 } 4716 } 4717} 4718 4719// is_headless_jre() 4720// 4721// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4722// in order to report if we are running in a headless jre 4723// 4724// Since JDK8 xawt/libmawt.so was moved into the same directory 4725// as libawt.so, and renamed libawt_xawt.so 4726// 4727bool os::is_headless_jre() { 4728#ifdef __APPLE__ 4729 // We no longer build headless-only on Mac OS X 4730 return false; 4731#else 4732 struct stat statbuf; 4733 char buf[MAXPATHLEN]; 4734 char libmawtpath[MAXPATHLEN]; 4735 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4736 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4737 char *p; 4738 4739 // Get path to libjvm.so 4740 os::jvm_path(buf, sizeof(buf)); 4741 4742 // Get rid of libjvm.so 4743 p = strrchr(buf, '/'); 4744 if (p == NULL) return false; 4745 else *p = '\0'; 4746 4747 // Get rid of client or server 4748 p = strrchr(buf, '/'); 4749 if (p == NULL) return false; 4750 else *p = '\0'; 4751 4752 // check xawt/libmawt.so 4753 strcpy(libmawtpath, buf); 4754 strcat(libmawtpath, xawtstr); 4755 if (::stat(libmawtpath, &statbuf) == 0) return false; 4756 4757 // check libawt_xawt.so 4758 strcpy(libmawtpath, buf); 4759 strcat(libmawtpath, new_xawtstr); 4760 if (::stat(libmawtpath, &statbuf) == 0) return false; 4761 4762 return true; 4763#endif 4764} 4765 4766// Get the default path to the core file 4767// Returns the length of the string 4768int os::get_core_path(char* buffer, size_t bufferSize) { 4769 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4770 4771 // Truncate if theoretical string was longer than bufferSize 4772 n = MIN2(n, (int)bufferSize); 4773 4774 return n; 4775} 4776 4777#ifndef PRODUCT 4778void TestReserveMemorySpecial_test() { 4779 // No tests available for this platform 4780} 4781#endif 4782