os_bsd.cpp revision 5580:e006d2e25bc7
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(PPC) 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()) * 0.000001; 949} 950 951jlong os::elapsed_counter() { 952 timeval time; 953 int status = gettimeofday(&time, NULL); 954 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count; 955} 956 957jlong os::elapsed_frequency() { 958 return (1000 * 1000); 959} 960 961bool os::supports_vtime() { return true; } 962bool os::enable_vtime() { return false; } 963bool os::vtime_enabled() { return false; } 964 965double os::elapsedVTime() { 966 // better than nothing, but not much 967 return elapsedTime(); 968} 969 970jlong os::javaTimeMillis() { 971 timeval time; 972 int status = gettimeofday(&time, NULL); 973 assert(status != -1, "bsd error"); 974 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 975} 976 977#ifndef CLOCK_MONOTONIC 978#define CLOCK_MONOTONIC (1) 979#endif 980 981#ifdef __APPLE__ 982void os::Bsd::clock_init() { 983 // XXXDARWIN: Investigate replacement monotonic clock 984} 985#else 986void os::Bsd::clock_init() { 987 struct timespec res; 988 struct timespec tp; 989 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 990 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 991 // yes, monotonic clock is supported 992 _clock_gettime = ::clock_gettime; 993 } 994} 995#endif 996 997 998jlong os::javaTimeNanos() { 999 if (Bsd::supports_monotonic_clock()) { 1000 struct timespec tp; 1001 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp); 1002 assert(status == 0, "gettime error"); 1003 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1004 return result; 1005 } else { 1006 timeval time; 1007 int status = gettimeofday(&time, NULL); 1008 assert(status != -1, "bsd error"); 1009 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1010 return 1000 * usecs; 1011 } 1012} 1013 1014void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1015 if (Bsd::supports_monotonic_clock()) { 1016 info_ptr->max_value = ALL_64_BITS; 1017 1018 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1019 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1020 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1021 } else { 1022 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1023 info_ptr->max_value = ALL_64_BITS; 1024 1025 // gettimeofday is a real time clock so it skips 1026 info_ptr->may_skip_backward = true; 1027 info_ptr->may_skip_forward = true; 1028 } 1029 1030 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1031} 1032 1033// Return the real, user, and system times in seconds from an 1034// arbitrary fixed point in the past. 1035bool os::getTimesSecs(double* process_real_time, 1036 double* process_user_time, 1037 double* process_system_time) { 1038 struct tms ticks; 1039 clock_t real_ticks = times(&ticks); 1040 1041 if (real_ticks == (clock_t) (-1)) { 1042 return false; 1043 } else { 1044 double ticks_per_second = (double) clock_tics_per_sec; 1045 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1046 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1047 *process_real_time = ((double) real_ticks) / ticks_per_second; 1048 1049 return true; 1050 } 1051} 1052 1053 1054char * os::local_time_string(char *buf, size_t buflen) { 1055 struct tm t; 1056 time_t long_time; 1057 time(&long_time); 1058 localtime_r(&long_time, &t); 1059 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1060 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1061 t.tm_hour, t.tm_min, t.tm_sec); 1062 return buf; 1063} 1064 1065struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1066 return localtime_r(clock, res); 1067} 1068 1069//////////////////////////////////////////////////////////////////////////////// 1070// runtime exit support 1071 1072// Note: os::shutdown() might be called very early during initialization, or 1073// called from signal handler. Before adding something to os::shutdown(), make 1074// sure it is async-safe and can handle partially initialized VM. 1075void os::shutdown() { 1076 1077 // allow PerfMemory to attempt cleanup of any persistent resources 1078 perfMemory_exit(); 1079 1080 // needs to remove object in file system 1081 AttachListener::abort(); 1082 1083 // flush buffered output, finish log files 1084 ostream_abort(); 1085 1086 // Check for abort hook 1087 abort_hook_t abort_hook = Arguments::abort_hook(); 1088 if (abort_hook != NULL) { 1089 abort_hook(); 1090 } 1091 1092} 1093 1094// Note: os::abort() might be called very early during initialization, or 1095// called from signal handler. Before adding something to os::abort(), make 1096// sure it is async-safe and can handle partially initialized VM. 1097void os::abort(bool dump_core) { 1098 os::shutdown(); 1099 if (dump_core) { 1100#ifndef PRODUCT 1101 fdStream out(defaultStream::output_fd()); 1102 out.print_raw("Current thread is "); 1103 char buf[16]; 1104 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1105 out.print_raw_cr(buf); 1106 out.print_raw_cr("Dumping core ..."); 1107#endif 1108 ::abort(); // dump core 1109 } 1110 1111 ::exit(1); 1112} 1113 1114// Die immediately, no exit hook, no abort hook, no cleanup. 1115void os::die() { 1116 // _exit() on BsdThreads only kills current thread 1117 ::abort(); 1118} 1119 1120// unused on bsd for now. 1121void os::set_error_file(const char *logfile) {} 1122 1123 1124// This method is a copy of JDK's sysGetLastErrorString 1125// from src/solaris/hpi/src/system_md.c 1126 1127size_t os::lasterror(char *buf, size_t len) { 1128 1129 if (errno == 0) return 0; 1130 1131 const char *s = ::strerror(errno); 1132 size_t n = ::strlen(s); 1133 if (n >= len) { 1134 n = len - 1; 1135 } 1136 ::strncpy(buf, s, n); 1137 buf[n] = '\0'; 1138 return n; 1139} 1140 1141// Information of current thread in variety of formats 1142pid_t os::Bsd::gettid() { 1143 int retval = -1; 1144 1145#ifdef __APPLE__ //XNU kernel 1146 // despite the fact mach port is actually not a thread id use it 1147 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1148 retval = ::pthread_mach_thread_np(::pthread_self()); 1149 guarantee(retval != 0, "just checking"); 1150 return retval; 1151 1152#elif __FreeBSD__ 1153 retval = syscall(SYS_thr_self); 1154#elif __OpenBSD__ 1155 retval = syscall(SYS_getthrid); 1156#elif __NetBSD__ 1157 retval = (pid_t) syscall(SYS__lwp_self); 1158#endif 1159 1160 if (retval == -1) { 1161 return getpid(); 1162 } 1163} 1164 1165intx os::current_thread_id() { 1166#ifdef __APPLE__ 1167 return (intx)::pthread_mach_thread_np(::pthread_self()); 1168#else 1169 return (intx)::pthread_self(); 1170#endif 1171} 1172 1173int os::current_process_id() { 1174 1175 // Under the old bsd thread library, bsd gives each thread 1176 // its own process id. Because of this each thread will return 1177 // a different pid if this method were to return the result 1178 // of getpid(2). Bsd provides no api that returns the pid 1179 // of the launcher thread for the vm. This implementation 1180 // returns a unique pid, the pid of the launcher thread 1181 // that starts the vm 'process'. 1182 1183 // Under the NPTL, getpid() returns the same pid as the 1184 // launcher thread rather than a unique pid per thread. 1185 // Use gettid() if you want the old pre NPTL behaviour. 1186 1187 // if you are looking for the result of a call to getpid() that 1188 // returns a unique pid for the calling thread, then look at the 1189 // OSThread::thread_id() method in osThread_bsd.hpp file 1190 1191 return (int)(_initial_pid ? _initial_pid : getpid()); 1192} 1193 1194// DLL functions 1195 1196#define JNI_LIB_PREFIX "lib" 1197#ifdef __APPLE__ 1198#define JNI_LIB_SUFFIX ".dylib" 1199#else 1200#define JNI_LIB_SUFFIX ".so" 1201#endif 1202 1203const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1204 1205// This must be hard coded because it's the system's temporary 1206// directory not the java application's temp directory, ala java.io.tmpdir. 1207#ifdef __APPLE__ 1208// macosx has a secure per-user temporary directory 1209char temp_path_storage[PATH_MAX]; 1210const char* os::get_temp_directory() { 1211 static char *temp_path = NULL; 1212 if (temp_path == NULL) { 1213 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1214 if (pathSize == 0 || pathSize > PATH_MAX) { 1215 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1216 } 1217 temp_path = temp_path_storage; 1218 } 1219 return temp_path; 1220} 1221#else /* __APPLE__ */ 1222const char* os::get_temp_directory() { return "/tmp"; } 1223#endif /* __APPLE__ */ 1224 1225static bool file_exists(const char* filename) { 1226 struct stat statbuf; 1227 if (filename == NULL || strlen(filename) == 0) { 1228 return false; 1229 } 1230 return os::stat(filename, &statbuf) == 0; 1231} 1232 1233bool os::dll_build_name(char* buffer, size_t buflen, 1234 const char* pname, const char* fname) { 1235 bool retval = false; 1236 // Copied from libhpi 1237 const size_t pnamelen = pname ? strlen(pname) : 0; 1238 1239 // Return error on buffer overflow. 1240 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1241 return retval; 1242 } 1243 1244 if (pnamelen == 0) { 1245 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1246 retval = true; 1247 } else if (strchr(pname, *os::path_separator()) != NULL) { 1248 int n; 1249 char** pelements = split_path(pname, &n); 1250 if (pelements == NULL) { 1251 return false; 1252 } 1253 for (int i = 0 ; i < n ; i++) { 1254 // Really shouldn't be NULL, but check can't hurt 1255 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1256 continue; // skip the empty path values 1257 } 1258 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1259 pelements[i], fname); 1260 if (file_exists(buffer)) { 1261 retval = true; 1262 break; 1263 } 1264 } 1265 // release the storage 1266 for (int i = 0 ; i < n ; i++) { 1267 if (pelements[i] != NULL) { 1268 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1269 } 1270 } 1271 if (pelements != NULL) { 1272 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1273 } 1274 } else { 1275 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1276 retval = true; 1277 } 1278 return retval; 1279} 1280 1281// check if addr is inside libjvm.so 1282bool os::address_is_in_vm(address addr) { 1283 static address libjvm_base_addr; 1284 Dl_info dlinfo; 1285 1286 if (libjvm_base_addr == NULL) { 1287 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1288 libjvm_base_addr = (address)dlinfo.dli_fbase; 1289 } 1290 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1291 } 1292 1293 if (dladdr((void *)addr, &dlinfo) != 0) { 1294 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1295 } 1296 1297 return false; 1298} 1299 1300 1301#define MACH_MAXSYMLEN 256 1302 1303bool os::dll_address_to_function_name(address addr, char *buf, 1304 int buflen, int *offset) { 1305 // buf is not optional, but offset is optional 1306 assert(buf != NULL, "sanity check"); 1307 1308 Dl_info dlinfo; 1309 char localbuf[MACH_MAXSYMLEN]; 1310 1311 if (dladdr((void*)addr, &dlinfo) != 0) { 1312 // see if we have a matching symbol 1313 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1314 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1315 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1316 } 1317 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1318 return true; 1319 } 1320 // no matching symbol so try for just file info 1321 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1322 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1323 buf, buflen, offset, dlinfo.dli_fname)) { 1324 return true; 1325 } 1326 } 1327 1328 // Handle non-dynamic manually: 1329 if (dlinfo.dli_fbase != NULL && 1330 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1331 dlinfo.dli_fbase)) { 1332 if (!Decoder::demangle(localbuf, buf, buflen)) { 1333 jio_snprintf(buf, buflen, "%s", localbuf); 1334 } 1335 return true; 1336 } 1337 } 1338 buf[0] = '\0'; 1339 if (offset != NULL) *offset = -1; 1340 return false; 1341} 1342 1343// ported from solaris version 1344bool os::dll_address_to_library_name(address addr, char* buf, 1345 int buflen, int* offset) { 1346 // buf is not optional, but offset is optional 1347 assert(buf != NULL, "sanity check"); 1348 1349 Dl_info dlinfo; 1350 1351 if (dladdr((void*)addr, &dlinfo) != 0) { 1352 if (dlinfo.dli_fname != NULL) { 1353 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1354 } 1355 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1356 *offset = addr - (address)dlinfo.dli_fbase; 1357 } 1358 return true; 1359 } 1360 1361 buf[0] = '\0'; 1362 if (offset) *offset = -1; 1363 return false; 1364} 1365 1366// Loads .dll/.so and 1367// in case of error it checks if .dll/.so was built for the 1368// same architecture as Hotspot is running on 1369 1370#ifdef __APPLE__ 1371void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1372 void * result= ::dlopen(filename, RTLD_LAZY); 1373 if (result != NULL) { 1374 // Successful loading 1375 return result; 1376 } 1377 1378 // Read system error message into ebuf 1379 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1380 ebuf[ebuflen-1]='\0'; 1381 1382 return NULL; 1383} 1384#else 1385void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1386{ 1387 void * result= ::dlopen(filename, RTLD_LAZY); 1388 if (result != NULL) { 1389 // Successful loading 1390 return result; 1391 } 1392 1393 Elf32_Ehdr elf_head; 1394 1395 // Read system error message into ebuf 1396 // It may or may not be overwritten below 1397 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1398 ebuf[ebuflen-1]='\0'; 1399 int diag_msg_max_length=ebuflen-strlen(ebuf); 1400 char* diag_msg_buf=ebuf+strlen(ebuf); 1401 1402 if (diag_msg_max_length==0) { 1403 // No more space in ebuf for additional diagnostics message 1404 return NULL; 1405 } 1406 1407 1408 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1409 1410 if (file_descriptor < 0) { 1411 // Can't open library, report dlerror() message 1412 return NULL; 1413 } 1414 1415 bool failed_to_read_elf_head= 1416 (sizeof(elf_head)!= 1417 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 1418 1419 ::close(file_descriptor); 1420 if (failed_to_read_elf_head) { 1421 // file i/o error - report dlerror() msg 1422 return NULL; 1423 } 1424 1425 typedef struct { 1426 Elf32_Half code; // Actual value as defined in elf.h 1427 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1428 char elf_class; // 32 or 64 bit 1429 char endianess; // MSB or LSB 1430 char* name; // String representation 1431 } arch_t; 1432 1433 #ifndef EM_486 1434 #define EM_486 6 /* Intel 80486 */ 1435 #endif 1436 1437 #ifndef EM_MIPS_RS3_LE 1438 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1439 #endif 1440 1441 #ifndef EM_PPC64 1442 #define EM_PPC64 21 /* PowerPC64 */ 1443 #endif 1444 1445 #ifndef EM_S390 1446 #define EM_S390 22 /* IBM System/390 */ 1447 #endif 1448 1449 #ifndef EM_IA_64 1450 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1451 #endif 1452 1453 #ifndef EM_X86_64 1454 #define EM_X86_64 62 /* AMD x86-64 */ 1455 #endif 1456 1457 static const arch_t arch_array[]={ 1458 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1459 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1460 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1461 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1462 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1463 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1464 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1465 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1466 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1467 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1468 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1469 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1470 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1471 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1472 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1473 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1474 }; 1475 1476 #if (defined IA32) 1477 static Elf32_Half running_arch_code=EM_386; 1478 #elif (defined AMD64) 1479 static Elf32_Half running_arch_code=EM_X86_64; 1480 #elif (defined IA64) 1481 static Elf32_Half running_arch_code=EM_IA_64; 1482 #elif (defined __sparc) && (defined _LP64) 1483 static Elf32_Half running_arch_code=EM_SPARCV9; 1484 #elif (defined __sparc) && (!defined _LP64) 1485 static Elf32_Half running_arch_code=EM_SPARC; 1486 #elif (defined __powerpc64__) 1487 static Elf32_Half running_arch_code=EM_PPC64; 1488 #elif (defined __powerpc__) 1489 static Elf32_Half running_arch_code=EM_PPC; 1490 #elif (defined ARM) 1491 static Elf32_Half running_arch_code=EM_ARM; 1492 #elif (defined S390) 1493 static Elf32_Half running_arch_code=EM_S390; 1494 #elif (defined ALPHA) 1495 static Elf32_Half running_arch_code=EM_ALPHA; 1496 #elif (defined MIPSEL) 1497 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1498 #elif (defined PARISC) 1499 static Elf32_Half running_arch_code=EM_PARISC; 1500 #elif (defined MIPS) 1501 static Elf32_Half running_arch_code=EM_MIPS; 1502 #elif (defined M68K) 1503 static Elf32_Half running_arch_code=EM_68K; 1504 #else 1505 #error Method os::dll_load requires that one of following is defined:\ 1506 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1507 #endif 1508 1509 // Identify compatability class for VM's architecture and library's architecture 1510 // Obtain string descriptions for architectures 1511 1512 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1513 int running_arch_index=-1; 1514 1515 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 1516 if (running_arch_code == arch_array[i].code) { 1517 running_arch_index = i; 1518 } 1519 if (lib_arch.code == arch_array[i].code) { 1520 lib_arch.compat_class = arch_array[i].compat_class; 1521 lib_arch.name = arch_array[i].name; 1522 } 1523 } 1524 1525 assert(running_arch_index != -1, 1526 "Didn't find running architecture code (running_arch_code) in arch_array"); 1527 if (running_arch_index == -1) { 1528 // Even though running architecture detection failed 1529 // we may still continue with reporting dlerror() message 1530 return NULL; 1531 } 1532 1533 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1534 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1535 return NULL; 1536 } 1537 1538#ifndef S390 1539 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1540 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1541 return NULL; 1542 } 1543#endif // !S390 1544 1545 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1546 if ( lib_arch.name!=NULL ) { 1547 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1548 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1549 lib_arch.name, arch_array[running_arch_index].name); 1550 } else { 1551 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1552 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1553 lib_arch.code, 1554 arch_array[running_arch_index].name); 1555 } 1556 } 1557 1558 return NULL; 1559} 1560#endif /* !__APPLE__ */ 1561 1562// XXX: Do we need a lock around this as per Linux? 1563void* os::dll_lookup(void* handle, const char* name) { 1564 return dlsym(handle, name); 1565} 1566 1567 1568static bool _print_ascii_file(const char* filename, outputStream* st) { 1569 int fd = ::open(filename, O_RDONLY); 1570 if (fd == -1) { 1571 return false; 1572 } 1573 1574 char buf[32]; 1575 int bytes; 1576 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1577 st->print_raw(buf, bytes); 1578 } 1579 1580 ::close(fd); 1581 1582 return true; 1583} 1584 1585void os::print_dll_info(outputStream *st) { 1586 st->print_cr("Dynamic libraries:"); 1587#ifdef RTLD_DI_LINKMAP 1588 Dl_info dli; 1589 void *handle; 1590 Link_map *map; 1591 Link_map *p; 1592 1593 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1594 dli.dli_fname == NULL) { 1595 st->print_cr("Error: Cannot print dynamic libraries."); 1596 return; 1597 } 1598 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1599 if (handle == NULL) { 1600 st->print_cr("Error: Cannot print dynamic libraries."); 1601 return; 1602 } 1603 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1604 if (map == NULL) { 1605 st->print_cr("Error: Cannot print dynamic libraries."); 1606 return; 1607 } 1608 1609 while (map->l_prev != NULL) 1610 map = map->l_prev; 1611 1612 while (map != NULL) { 1613 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1614 map = map->l_next; 1615 } 1616 1617 dlclose(handle); 1618#elif defined(__APPLE__) 1619 uint32_t count; 1620 uint32_t i; 1621 1622 count = _dyld_image_count(); 1623 for (i = 1; i < count; i++) { 1624 const char *name = _dyld_get_image_name(i); 1625 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 1626 st->print_cr(PTR_FORMAT " \t%s", slide, name); 1627 } 1628#else 1629 st->print_cr("Error: Cannot print dynamic libraries."); 1630#endif 1631} 1632 1633void os::print_os_info_brief(outputStream* st) { 1634 st->print("Bsd"); 1635 1636 os::Posix::print_uname_info(st); 1637} 1638 1639void os::print_os_info(outputStream* st) { 1640 st->print("OS:"); 1641 st->print("Bsd"); 1642 1643 os::Posix::print_uname_info(st); 1644 1645 os::Posix::print_rlimit_info(st); 1646 1647 os::Posix::print_load_average(st); 1648} 1649 1650void os::pd_print_cpu_info(outputStream* st) { 1651 // Nothing to do for now. 1652} 1653 1654void os::print_memory_info(outputStream* st) { 1655 1656 st->print("Memory:"); 1657 st->print(" %dk page", os::vm_page_size()>>10); 1658 1659 st->print(", physical " UINT64_FORMAT "k", 1660 os::physical_memory() >> 10); 1661 st->print("(" UINT64_FORMAT "k free)", 1662 os::available_memory() >> 10); 1663 st->cr(); 1664 1665 // meminfo 1666 st->print("\n/proc/meminfo:\n"); 1667 _print_ascii_file("/proc/meminfo", st); 1668 st->cr(); 1669} 1670 1671// Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific 1672// but they're the same for all the bsd arch that we support 1673// and they're the same for solaris but there's no common place to put this. 1674const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR", 1675 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG", 1676 "ILL_COPROC", "ILL_BADSTK" }; 1677 1678const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV", 1679 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES", 1680 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" }; 1681 1682const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" }; 1683 1684const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" }; 1685 1686void os::print_siginfo(outputStream* st, void* siginfo) { 1687 st->print("siginfo:"); 1688 1689 const int buflen = 100; 1690 char buf[buflen]; 1691 siginfo_t *si = (siginfo_t*)siginfo; 1692 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen)); 1693 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) { 1694 st->print("si_errno=%s", buf); 1695 } else { 1696 st->print("si_errno=%d", si->si_errno); 1697 } 1698 const int c = si->si_code; 1699 assert(c > 0, "unexpected si_code"); 1700 switch (si->si_signo) { 1701 case SIGILL: 1702 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]); 1703 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1704 break; 1705 case SIGFPE: 1706 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]); 1707 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1708 break; 1709 case SIGSEGV: 1710 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]); 1711 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1712 break; 1713 case SIGBUS: 1714 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]); 1715 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 1716 break; 1717 default: 1718 st->print(", si_code=%d", si->si_code); 1719 // no si_addr 1720 } 1721 1722 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1723 UseSharedSpaces) { 1724 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1725 if (mapinfo->is_in_shared_space(si->si_addr)) { 1726 st->print("\n\nError accessing class data sharing archive." \ 1727 " Mapped file inaccessible during execution, " \ 1728 " possible disk/network problem."); 1729 } 1730 } 1731 st->cr(); 1732} 1733 1734 1735static void print_signal_handler(outputStream* st, int sig, 1736 char* buf, size_t buflen); 1737 1738void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1739 st->print_cr("Signal Handlers:"); 1740 print_signal_handler(st, SIGSEGV, buf, buflen); 1741 print_signal_handler(st, SIGBUS , buf, buflen); 1742 print_signal_handler(st, SIGFPE , buf, buflen); 1743 print_signal_handler(st, SIGPIPE, buf, buflen); 1744 print_signal_handler(st, SIGXFSZ, buf, buflen); 1745 print_signal_handler(st, SIGILL , buf, buflen); 1746 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1747 print_signal_handler(st, SR_signum, buf, buflen); 1748 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1749 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1750 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1751 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1752} 1753 1754static char saved_jvm_path[MAXPATHLEN] = {0}; 1755 1756// Find the full path to the current module, libjvm 1757void os::jvm_path(char *buf, jint buflen) { 1758 // Error checking. 1759 if (buflen < MAXPATHLEN) { 1760 assert(false, "must use a large-enough buffer"); 1761 buf[0] = '\0'; 1762 return; 1763 } 1764 // Lazy resolve the path to current module. 1765 if (saved_jvm_path[0] != 0) { 1766 strcpy(buf, saved_jvm_path); 1767 return; 1768 } 1769 1770 char dli_fname[MAXPATHLEN]; 1771 bool ret = dll_address_to_library_name( 1772 CAST_FROM_FN_PTR(address, os::jvm_path), 1773 dli_fname, sizeof(dli_fname), NULL); 1774 assert(ret, "cannot locate libjvm"); 1775 char *rp = NULL; 1776 if (ret && dli_fname[0] != '\0') { 1777 rp = realpath(dli_fname, buf); 1778 } 1779 if (rp == NULL) 1780 return; 1781 1782 if (Arguments::created_by_gamma_launcher()) { 1783 // Support for the gamma launcher. Typical value for buf is 1784 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at 1785 // the right place in the string, then assume we are installed in a JDK and 1786 // we're done. Otherwise, check for a JAVA_HOME environment variable and 1787 // construct a path to the JVM being overridden. 1788 1789 const char *p = buf + strlen(buf) - 1; 1790 for (int count = 0; p > buf && count < 5; ++count) { 1791 for (--p; p > buf && *p != '/'; --p) 1792 /* empty */ ; 1793 } 1794 1795 if (strncmp(p, "/jre/lib/", 9) != 0) { 1796 // Look for JAVA_HOME in the environment. 1797 char* java_home_var = ::getenv("JAVA_HOME"); 1798 if (java_home_var != NULL && java_home_var[0] != 0) { 1799 char* jrelib_p; 1800 int len; 1801 1802 // Check the current module name "libjvm" 1803 p = strrchr(buf, '/'); 1804 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1805 1806 rp = realpath(java_home_var, buf); 1807 if (rp == NULL) 1808 return; 1809 1810 // determine if this is a legacy image or modules image 1811 // modules image doesn't have "jre" subdirectory 1812 len = strlen(buf); 1813 jrelib_p = buf + len; 1814 1815 // Add the appropriate library subdir 1816 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1817 if (0 != access(buf, F_OK)) { 1818 snprintf(jrelib_p, buflen-len, "/lib"); 1819 } 1820 1821 // Add the appropriate client or server subdir 1822 len = strlen(buf); 1823 jrelib_p = buf + len; 1824 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1825 if (0 != access(buf, F_OK)) { 1826 snprintf(jrelib_p, buflen-len, ""); 1827 } 1828 1829 // If the path exists within JAVA_HOME, add the JVM library name 1830 // to complete the path to JVM being overridden. Otherwise fallback 1831 // to the path to the current library. 1832 if (0 == access(buf, F_OK)) { 1833 // Use current module name "libjvm" 1834 len = strlen(buf); 1835 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1836 } else { 1837 // Fall back to path of current library 1838 rp = realpath(dli_fname, buf); 1839 if (rp == NULL) 1840 return; 1841 } 1842 } 1843 } 1844 } 1845 1846 strcpy(saved_jvm_path, buf); 1847} 1848 1849void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1850 // no prefix required, not even "_" 1851} 1852 1853void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1854 // no suffix required 1855} 1856 1857//////////////////////////////////////////////////////////////////////////////// 1858// sun.misc.Signal support 1859 1860static volatile jint sigint_count = 0; 1861 1862static void 1863UserHandler(int sig, void *siginfo, void *context) { 1864 // 4511530 - sem_post is serialized and handled by the manager thread. When 1865 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1866 // don't want to flood the manager thread with sem_post requests. 1867 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1868 return; 1869 1870 // Ctrl-C is pressed during error reporting, likely because the error 1871 // handler fails to abort. Let VM die immediately. 1872 if (sig == SIGINT && is_error_reported()) { 1873 os::die(); 1874 } 1875 1876 os::signal_notify(sig); 1877} 1878 1879void* os::user_handler() { 1880 return CAST_FROM_FN_PTR(void*, UserHandler); 1881} 1882 1883extern "C" { 1884 typedef void (*sa_handler_t)(int); 1885 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1886} 1887 1888void* os::signal(int signal_number, void* handler) { 1889 struct sigaction sigAct, oldSigAct; 1890 1891 sigfillset(&(sigAct.sa_mask)); 1892 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1893 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1894 1895 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1896 // -1 means registration failed 1897 return (void *)-1; 1898 } 1899 1900 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1901} 1902 1903void os::signal_raise(int signal_number) { 1904 ::raise(signal_number); 1905} 1906 1907/* 1908 * The following code is moved from os.cpp for making this 1909 * code platform specific, which it is by its very nature. 1910 */ 1911 1912// Will be modified when max signal is changed to be dynamic 1913int os::sigexitnum_pd() { 1914 return NSIG; 1915} 1916 1917// a counter for each possible signal value 1918static volatile jint pending_signals[NSIG+1] = { 0 }; 1919 1920// Bsd(POSIX) specific hand shaking semaphore. 1921#ifdef __APPLE__ 1922typedef semaphore_t os_semaphore_t; 1923#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1924#define SEM_WAIT(sem) semaphore_wait(sem) 1925#define SEM_POST(sem) semaphore_signal(sem) 1926#define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1927#else 1928typedef sem_t os_semaphore_t; 1929#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1930#define SEM_WAIT(sem) sem_wait(&sem) 1931#define SEM_POST(sem) sem_post(&sem) 1932#define SEM_DESTROY(sem) sem_destroy(&sem) 1933#endif 1934 1935class Semaphore : public StackObj { 1936 public: 1937 Semaphore(); 1938 ~Semaphore(); 1939 void signal(); 1940 void wait(); 1941 bool trywait(); 1942 bool timedwait(unsigned int sec, int nsec); 1943 private: 1944 jlong currenttime() const; 1945 os_semaphore_t _semaphore; 1946}; 1947 1948Semaphore::Semaphore() : _semaphore(0) { 1949 SEM_INIT(_semaphore, 0); 1950} 1951 1952Semaphore::~Semaphore() { 1953 SEM_DESTROY(_semaphore); 1954} 1955 1956void Semaphore::signal() { 1957 SEM_POST(_semaphore); 1958} 1959 1960void Semaphore::wait() { 1961 SEM_WAIT(_semaphore); 1962} 1963 1964jlong Semaphore::currenttime() const { 1965 struct timeval tv; 1966 gettimeofday(&tv, NULL); 1967 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1968} 1969 1970#ifdef __APPLE__ 1971bool Semaphore::trywait() { 1972 return timedwait(0, 0); 1973} 1974 1975bool Semaphore::timedwait(unsigned int sec, int nsec) { 1976 kern_return_t kr = KERN_ABORTED; 1977 mach_timespec_t waitspec; 1978 waitspec.tv_sec = sec; 1979 waitspec.tv_nsec = nsec; 1980 1981 jlong starttime = currenttime(); 1982 1983 kr = semaphore_timedwait(_semaphore, waitspec); 1984 while (kr == KERN_ABORTED) { 1985 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1986 1987 jlong current = currenttime(); 1988 jlong passedtime = current - starttime; 1989 1990 if (passedtime >= totalwait) { 1991 waitspec.tv_sec = 0; 1992 waitspec.tv_nsec = 0; 1993 } else { 1994 jlong waittime = totalwait - (current - starttime); 1995 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 1996 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 1997 } 1998 1999 kr = semaphore_timedwait(_semaphore, waitspec); 2000 } 2001 2002 return kr == KERN_SUCCESS; 2003} 2004 2005#else 2006 2007bool Semaphore::trywait() { 2008 return sem_trywait(&_semaphore) == 0; 2009} 2010 2011bool Semaphore::timedwait(unsigned int sec, int nsec) { 2012 struct timespec ts; 2013 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2014 2015 while (1) { 2016 int result = sem_timedwait(&_semaphore, &ts); 2017 if (result == 0) { 2018 return true; 2019 } else if (errno == EINTR) { 2020 continue; 2021 } else if (errno == ETIMEDOUT) { 2022 return false; 2023 } else { 2024 return false; 2025 } 2026 } 2027} 2028 2029#endif // __APPLE__ 2030 2031static os_semaphore_t sig_sem; 2032static Semaphore sr_semaphore; 2033 2034void os::signal_init_pd() { 2035 // Initialize signal structures 2036 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2037 2038 // Initialize signal semaphore 2039 ::SEM_INIT(sig_sem, 0); 2040} 2041 2042void os::signal_notify(int sig) { 2043 Atomic::inc(&pending_signals[sig]); 2044 ::SEM_POST(sig_sem); 2045} 2046 2047static int check_pending_signals(bool wait) { 2048 Atomic::store(0, &sigint_count); 2049 for (;;) { 2050 for (int i = 0; i < NSIG + 1; i++) { 2051 jint n = pending_signals[i]; 2052 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2053 return i; 2054 } 2055 } 2056 if (!wait) { 2057 return -1; 2058 } 2059 JavaThread *thread = JavaThread::current(); 2060 ThreadBlockInVM tbivm(thread); 2061 2062 bool threadIsSuspended; 2063 do { 2064 thread->set_suspend_equivalent(); 2065 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2066 ::SEM_WAIT(sig_sem); 2067 2068 // were we externally suspended while we were waiting? 2069 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2070 if (threadIsSuspended) { 2071 // 2072 // The semaphore has been incremented, but while we were waiting 2073 // another thread suspended us. We don't want to continue running 2074 // while suspended because that would surprise the thread that 2075 // suspended us. 2076 // 2077 ::SEM_POST(sig_sem); 2078 2079 thread->java_suspend_self(); 2080 } 2081 } while (threadIsSuspended); 2082 } 2083} 2084 2085int os::signal_lookup() { 2086 return check_pending_signals(false); 2087} 2088 2089int os::signal_wait() { 2090 return check_pending_signals(true); 2091} 2092 2093//////////////////////////////////////////////////////////////////////////////// 2094// Virtual Memory 2095 2096int os::vm_page_size() { 2097 // Seems redundant as all get out 2098 assert(os::Bsd::page_size() != -1, "must call os::init"); 2099 return os::Bsd::page_size(); 2100} 2101 2102// Solaris allocates memory by pages. 2103int os::vm_allocation_granularity() { 2104 assert(os::Bsd::page_size() != -1, "must call os::init"); 2105 return os::Bsd::page_size(); 2106} 2107 2108// Rationale behind this function: 2109// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2110// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2111// samples for JITted code. Here we create private executable mapping over the code cache 2112// and then we can use standard (well, almost, as mapping can change) way to provide 2113// info for the reporting script by storing timestamp and location of symbol 2114void bsd_wrap_code(char* base, size_t size) { 2115 static volatile jint cnt = 0; 2116 2117 if (!UseOprofile) { 2118 return; 2119 } 2120 2121 char buf[PATH_MAX + 1]; 2122 int num = Atomic::add(1, &cnt); 2123 2124 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2125 os::get_temp_directory(), os::current_process_id(), num); 2126 unlink(buf); 2127 2128 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2129 2130 if (fd != -1) { 2131 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2132 if (rv != (off_t)-1) { 2133 if (::write(fd, "", 1) == 1) { 2134 mmap(base, size, 2135 PROT_READ|PROT_WRITE|PROT_EXEC, 2136 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2137 } 2138 } 2139 ::close(fd); 2140 unlink(buf); 2141 } 2142} 2143 2144static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2145 int err) { 2146 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2147 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2148 strerror(err), err); 2149} 2150 2151// NOTE: Bsd kernel does not really reserve the pages for us. 2152// All it does is to check if there are enough free pages 2153// left at the time of mmap(). This could be a potential 2154// problem. 2155bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2156 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2157#ifdef __OpenBSD__ 2158 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2159 if (::mprotect(addr, size, prot) == 0) { 2160 return true; 2161 } 2162#else 2163 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2164 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2165 if (res != (uintptr_t) MAP_FAILED) { 2166 return true; 2167 } 2168#endif 2169 2170 // Warn about any commit errors we see in non-product builds just 2171 // in case mmap() doesn't work as described on the man page. 2172 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2173 2174 return false; 2175} 2176 2177bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2178 bool exec) { 2179 // alignment_hint is ignored on this OS 2180 return pd_commit_memory(addr, size, exec); 2181} 2182 2183void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2184 const char* mesg) { 2185 assert(mesg != NULL, "mesg must be specified"); 2186 if (!pd_commit_memory(addr, size, exec)) { 2187 // add extra info in product mode for vm_exit_out_of_memory(): 2188 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2189 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2190 } 2191} 2192 2193void os::pd_commit_memory_or_exit(char* addr, size_t size, 2194 size_t alignment_hint, bool exec, 2195 const char* mesg) { 2196 // alignment_hint is ignored on this OS 2197 pd_commit_memory_or_exit(addr, size, exec, mesg); 2198} 2199 2200void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2201} 2202 2203void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2204 ::madvise(addr, bytes, MADV_DONTNEED); 2205} 2206 2207void os::numa_make_global(char *addr, size_t bytes) { 2208} 2209 2210void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2211} 2212 2213bool os::numa_topology_changed() { return false; } 2214 2215size_t os::numa_get_groups_num() { 2216 return 1; 2217} 2218 2219int os::numa_get_group_id() { 2220 return 0; 2221} 2222 2223size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2224 if (size > 0) { 2225 ids[0] = 0; 2226 return 1; 2227 } 2228 return 0; 2229} 2230 2231bool os::get_page_info(char *start, page_info* info) { 2232 return false; 2233} 2234 2235char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2236 return end; 2237} 2238 2239 2240bool os::pd_uncommit_memory(char* addr, size_t size) { 2241#ifdef __OpenBSD__ 2242 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2243 return ::mprotect(addr, size, PROT_NONE) == 0; 2244#else 2245 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2246 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2247 return res != (uintptr_t) MAP_FAILED; 2248#endif 2249} 2250 2251bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2252 return os::commit_memory(addr, size, !ExecMem); 2253} 2254 2255// If this is a growable mapping, remove the guard pages entirely by 2256// munmap()ping them. If not, just call uncommit_memory(). 2257bool os::remove_stack_guard_pages(char* addr, size_t size) { 2258 return os::uncommit_memory(addr, size); 2259} 2260 2261static address _highest_vm_reserved_address = NULL; 2262 2263// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2264// at 'requested_addr'. If there are existing memory mappings at the same 2265// location, however, they will be overwritten. If 'fixed' is false, 2266// 'requested_addr' is only treated as a hint, the return value may or 2267// may not start from the requested address. Unlike Bsd mmap(), this 2268// function returns NULL to indicate failure. 2269static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2270 char * addr; 2271 int flags; 2272 2273 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2274 if (fixed) { 2275 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2276 flags |= MAP_FIXED; 2277 } 2278 2279 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2280 // touch an uncommitted page. Otherwise, the read/write might 2281 // succeed if we have enough swap space to back the physical page. 2282 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2283 flags, -1, 0); 2284 2285 if (addr != MAP_FAILED) { 2286 // anon_mmap() should only get called during VM initialization, 2287 // don't need lock (actually we can skip locking even it can be called 2288 // from multiple threads, because _highest_vm_reserved_address is just a 2289 // hint about the upper limit of non-stack memory regions.) 2290 if ((address)addr + bytes > _highest_vm_reserved_address) { 2291 _highest_vm_reserved_address = (address)addr + bytes; 2292 } 2293 } 2294 2295 return addr == MAP_FAILED ? NULL : addr; 2296} 2297 2298// Don't update _highest_vm_reserved_address, because there might be memory 2299// regions above addr + size. If so, releasing a memory region only creates 2300// a hole in the address space, it doesn't help prevent heap-stack collision. 2301// 2302static int anon_munmap(char * addr, size_t size) { 2303 return ::munmap(addr, size) == 0; 2304} 2305 2306char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2307 size_t alignment_hint) { 2308 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2309} 2310 2311bool os::pd_release_memory(char* addr, size_t size) { 2312 return anon_munmap(addr, size); 2313} 2314 2315static bool bsd_mprotect(char* addr, size_t size, int prot) { 2316 // Bsd wants the mprotect address argument to be page aligned. 2317 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2318 2319 // According to SUSv3, mprotect() should only be used with mappings 2320 // established by mmap(), and mmap() always maps whole pages. Unaligned 2321 // 'addr' likely indicates problem in the VM (e.g. trying to change 2322 // protection of malloc'ed or statically allocated memory). Check the 2323 // caller if you hit this assert. 2324 assert(addr == bottom, "sanity check"); 2325 2326 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2327 return ::mprotect(bottom, size, prot) == 0; 2328} 2329 2330// Set protections specified 2331bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2332 bool is_committed) { 2333 unsigned int p = 0; 2334 switch (prot) { 2335 case MEM_PROT_NONE: p = PROT_NONE; break; 2336 case MEM_PROT_READ: p = PROT_READ; break; 2337 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2338 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2339 default: 2340 ShouldNotReachHere(); 2341 } 2342 // is_committed is unused. 2343 return bsd_mprotect(addr, bytes, p); 2344} 2345 2346bool os::guard_memory(char* addr, size_t size) { 2347 return bsd_mprotect(addr, size, PROT_NONE); 2348} 2349 2350bool os::unguard_memory(char* addr, size_t size) { 2351 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2352} 2353 2354bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2355 return false; 2356} 2357 2358// Large page support 2359 2360static size_t _large_page_size = 0; 2361 2362void os::large_page_init() { 2363} 2364 2365 2366char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2367 fatal("This code is not used or maintained."); 2368 2369 // "exec" is passed in but not used. Creating the shared image for 2370 // the code cache doesn't have an SHM_X executable permission to check. 2371 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2372 2373 key_t key = IPC_PRIVATE; 2374 char *addr; 2375 2376 bool warn_on_failure = UseLargePages && 2377 (!FLAG_IS_DEFAULT(UseLargePages) || 2378 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2379 ); 2380 char msg[128]; 2381 2382 // Create a large shared memory region to attach to based on size. 2383 // Currently, size is the total size of the heap 2384 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2385 if (shmid == -1) { 2386 // Possible reasons for shmget failure: 2387 // 1. shmmax is too small for Java heap. 2388 // > check shmmax value: cat /proc/sys/kernel/shmmax 2389 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2390 // 2. not enough large page memory. 2391 // > check available large pages: cat /proc/meminfo 2392 // > increase amount of large pages: 2393 // echo new_value > /proc/sys/vm/nr_hugepages 2394 // Note 1: different Bsd may use different name for this property, 2395 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2396 // Note 2: it's possible there's enough physical memory available but 2397 // they are so fragmented after a long run that they can't 2398 // coalesce into large pages. Try to reserve large pages when 2399 // the system is still "fresh". 2400 if (warn_on_failure) { 2401 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 2402 warning(msg); 2403 } 2404 return NULL; 2405 } 2406 2407 // attach to the region 2408 addr = (char*)shmat(shmid, req_addr, 0); 2409 int err = errno; 2410 2411 // Remove shmid. If shmat() is successful, the actual shared memory segment 2412 // will be deleted when it's detached by shmdt() or when the process 2413 // terminates. If shmat() is not successful this will remove the shared 2414 // segment immediately. 2415 shmctl(shmid, IPC_RMID, NULL); 2416 2417 if ((intptr_t)addr == -1) { 2418 if (warn_on_failure) { 2419 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 2420 warning(msg); 2421 } 2422 return NULL; 2423 } 2424 2425 // The memory is committed 2426 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC); 2427 2428 return addr; 2429} 2430 2431bool os::release_memory_special(char* base, size_t bytes) { 2432 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2433 // detaching the SHM segment will also delete it, see reserve_memory_special() 2434 int rslt = shmdt(base); 2435 if (rslt == 0) { 2436 tkr.record((address)base, bytes); 2437 return true; 2438 } else { 2439 tkr.discard(); 2440 return false; 2441 } 2442 2443} 2444 2445size_t os::large_page_size() { 2446 return _large_page_size; 2447} 2448 2449// HugeTLBFS allows application to commit large page memory on demand; 2450// with SysV SHM the entire memory region must be allocated as shared 2451// memory. 2452bool os::can_commit_large_page_memory() { 2453 return UseHugeTLBFS; 2454} 2455 2456bool os::can_execute_large_page_memory() { 2457 return UseHugeTLBFS; 2458} 2459 2460// Reserve memory at an arbitrary address, only if that area is 2461// available (and not reserved for something else). 2462 2463char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2464 const int max_tries = 10; 2465 char* base[max_tries]; 2466 size_t size[max_tries]; 2467 const size_t gap = 0x000000; 2468 2469 // Assert only that the size is a multiple of the page size, since 2470 // that's all that mmap requires, and since that's all we really know 2471 // about at this low abstraction level. If we need higher alignment, 2472 // we can either pass an alignment to this method or verify alignment 2473 // in one of the methods further up the call chain. See bug 5044738. 2474 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2475 2476 // Repeatedly allocate blocks until the block is allocated at the 2477 // right spot. Give up after max_tries. Note that reserve_memory() will 2478 // automatically update _highest_vm_reserved_address if the call is 2479 // successful. The variable tracks the highest memory address every reserved 2480 // by JVM. It is used to detect heap-stack collision if running with 2481 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2482 // space than needed, it could confuse the collision detecting code. To 2483 // solve the problem, save current _highest_vm_reserved_address and 2484 // calculate the correct value before return. 2485 address old_highest = _highest_vm_reserved_address; 2486 2487 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2488 // if kernel honors the hint then we can return immediately. 2489 char * addr = anon_mmap(requested_addr, bytes, false); 2490 if (addr == requested_addr) { 2491 return requested_addr; 2492 } 2493 2494 if (addr != NULL) { 2495 // mmap() is successful but it fails to reserve at the requested address 2496 anon_munmap(addr, bytes); 2497 } 2498 2499 int i; 2500 for (i = 0; i < max_tries; ++i) { 2501 base[i] = reserve_memory(bytes); 2502 2503 if (base[i] != NULL) { 2504 // Is this the block we wanted? 2505 if (base[i] == requested_addr) { 2506 size[i] = bytes; 2507 break; 2508 } 2509 2510 // Does this overlap the block we wanted? Give back the overlapped 2511 // parts and try again. 2512 2513 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2514 if (top_overlap >= 0 && top_overlap < bytes) { 2515 unmap_memory(base[i], top_overlap); 2516 base[i] += top_overlap; 2517 size[i] = bytes - top_overlap; 2518 } else { 2519 size_t bottom_overlap = base[i] + bytes - requested_addr; 2520 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2521 unmap_memory(requested_addr, bottom_overlap); 2522 size[i] = bytes - bottom_overlap; 2523 } else { 2524 size[i] = bytes; 2525 } 2526 } 2527 } 2528 } 2529 2530 // Give back the unused reserved pieces. 2531 2532 for (int j = 0; j < i; ++j) { 2533 if (base[j] != NULL) { 2534 unmap_memory(base[j], size[j]); 2535 } 2536 } 2537 2538 if (i < max_tries) { 2539 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2540 return requested_addr; 2541 } else { 2542 _highest_vm_reserved_address = old_highest; 2543 return NULL; 2544 } 2545} 2546 2547size_t os::read(int fd, void *buf, unsigned int nBytes) { 2548 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2549} 2550 2551// TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation. 2552// Solaris uses poll(), bsd uses park(). 2553// Poll() is likely a better choice, assuming that Thread.interrupt() 2554// generates a SIGUSRx signal. Note that SIGUSR1 can interfere with 2555// SIGSEGV, see 4355769. 2556 2557int os::sleep(Thread* thread, jlong millis, bool interruptible) { 2558 assert(thread == Thread::current(), "thread consistency check"); 2559 2560 ParkEvent * const slp = thread->_SleepEvent ; 2561 slp->reset() ; 2562 OrderAccess::fence() ; 2563 2564 if (interruptible) { 2565 jlong prevtime = javaTimeNanos(); 2566 2567 for (;;) { 2568 if (os::is_interrupted(thread, true)) { 2569 return OS_INTRPT; 2570 } 2571 2572 jlong newtime = javaTimeNanos(); 2573 2574 if (newtime - prevtime < 0) { 2575 // time moving backwards, should only happen if no monotonic clock 2576 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2577 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2578 } else { 2579 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2580 } 2581 2582 if(millis <= 0) { 2583 return OS_OK; 2584 } 2585 2586 prevtime = newtime; 2587 2588 { 2589 assert(thread->is_Java_thread(), "sanity check"); 2590 JavaThread *jt = (JavaThread *) thread; 2591 ThreadBlockInVM tbivm(jt); 2592 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 2593 2594 jt->set_suspend_equivalent(); 2595 // cleared by handle_special_suspend_equivalent_condition() or 2596 // java_suspend_self() via check_and_wait_while_suspended() 2597 2598 slp->park(millis); 2599 2600 // were we externally suspended while we were waiting? 2601 jt->check_and_wait_while_suspended(); 2602 } 2603 } 2604 } else { 2605 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 2606 jlong prevtime = javaTimeNanos(); 2607 2608 for (;;) { 2609 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 2610 // the 1st iteration ... 2611 jlong newtime = javaTimeNanos(); 2612 2613 if (newtime - prevtime < 0) { 2614 // time moving backwards, should only happen if no monotonic clock 2615 // not a guarantee() because JVM should not abort on kernel/glibc bugs 2616 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 2617 } else { 2618 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 2619 } 2620 2621 if(millis <= 0) break ; 2622 2623 prevtime = newtime; 2624 slp->park(millis); 2625 } 2626 return OS_OK ; 2627 } 2628} 2629 2630int os::naked_sleep() { 2631 // %% make the sleep time an integer flag. for now use 1 millisec. 2632 return os::sleep(Thread::current(), 1, false); 2633} 2634 2635// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2636void os::infinite_sleep() { 2637 while (true) { // sleep forever ... 2638 ::sleep(100); // ... 100 seconds at a time 2639 } 2640} 2641 2642// Used to convert frequent JVM_Yield() to nops 2643bool os::dont_yield() { 2644 return DontYieldALot; 2645} 2646 2647void os::yield() { 2648 sched_yield(); 2649} 2650 2651os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 2652 2653void os::yield_all(int attempts) { 2654 // Yields to all threads, including threads with lower priorities 2655 // Threads on Bsd are all with same priority. The Solaris style 2656 // os::yield_all() with nanosleep(1ms) is not necessary. 2657 sched_yield(); 2658} 2659 2660// Called from the tight loops to possibly influence time-sharing heuristics 2661void os::loop_breaker(int attempts) { 2662 os::yield_all(attempts); 2663} 2664 2665//////////////////////////////////////////////////////////////////////////////// 2666// thread priority support 2667 2668// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2669// only supports dynamic priority, static priority must be zero. For real-time 2670// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2671// However, for large multi-threaded applications, SCHED_RR is not only slower 2672// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2673// of 5 runs - Sep 2005). 2674// 2675// The following code actually changes the niceness of kernel-thread/LWP. It 2676// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2677// not the entire user process, and user level threads are 1:1 mapped to kernel 2678// threads. It has always been the case, but could change in the future. For 2679// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2680// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2681 2682#if !defined(__APPLE__) 2683int os::java_to_os_priority[CriticalPriority + 1] = { 2684 19, // 0 Entry should never be used 2685 2686 0, // 1 MinPriority 2687 3, // 2 2688 6, // 3 2689 2690 10, // 4 2691 15, // 5 NormPriority 2692 18, // 6 2693 2694 21, // 7 2695 25, // 8 2696 28, // 9 NearMaxPriority 2697 2698 31, // 10 MaxPriority 2699 2700 31 // 11 CriticalPriority 2701}; 2702#else 2703/* Using Mach high-level priority assignments */ 2704int os::java_to_os_priority[CriticalPriority + 1] = { 2705 0, // 0 Entry should never be used (MINPRI_USER) 2706 2707 27, // 1 MinPriority 2708 28, // 2 2709 29, // 3 2710 2711 30, // 4 2712 31, // 5 NormPriority (BASEPRI_DEFAULT) 2713 32, // 6 2714 2715 33, // 7 2716 34, // 8 2717 35, // 9 NearMaxPriority 2718 2719 36, // 10 MaxPriority 2720 2721 36 // 11 CriticalPriority 2722}; 2723#endif 2724 2725static int prio_init() { 2726 if (ThreadPriorityPolicy == 1) { 2727 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2728 // if effective uid is not root. Perhaps, a more elegant way of doing 2729 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2730 if (geteuid() != 0) { 2731 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2732 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2733 } 2734 ThreadPriorityPolicy = 0; 2735 } 2736 } 2737 if (UseCriticalJavaThreadPriority) { 2738 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2739 } 2740 return 0; 2741} 2742 2743OSReturn os::set_native_priority(Thread* thread, int newpri) { 2744 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 2745 2746#ifdef __OpenBSD__ 2747 // OpenBSD pthread_setprio starves low priority threads 2748 return OS_OK; 2749#elif defined(__FreeBSD__) 2750 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2751#elif defined(__APPLE__) || defined(__NetBSD__) 2752 struct sched_param sp; 2753 int policy; 2754 pthread_t self = pthread_self(); 2755 2756 if (pthread_getschedparam(self, &policy, &sp) != 0) 2757 return OS_ERR; 2758 2759 sp.sched_priority = newpri; 2760 if (pthread_setschedparam(self, policy, &sp) != 0) 2761 return OS_ERR; 2762 2763 return OS_OK; 2764#else 2765 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2766 return (ret == 0) ? OS_OK : OS_ERR; 2767#endif 2768} 2769 2770OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2771 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 2772 *priority_ptr = java_to_os_priority[NormPriority]; 2773 return OS_OK; 2774 } 2775 2776 errno = 0; 2777#if defined(__OpenBSD__) || defined(__FreeBSD__) 2778 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2779#elif defined(__APPLE__) || defined(__NetBSD__) 2780 int policy; 2781 struct sched_param sp; 2782 2783 pthread_getschedparam(pthread_self(), &policy, &sp); 2784 *priority_ptr = sp.sched_priority; 2785#else 2786 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2787#endif 2788 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2789} 2790 2791// Hint to the underlying OS that a task switch would not be good. 2792// Void return because it's a hint and can fail. 2793void os::hint_no_preempt() {} 2794 2795//////////////////////////////////////////////////////////////////////////////// 2796// suspend/resume support 2797 2798// the low-level signal-based suspend/resume support is a remnant from the 2799// old VM-suspension that used to be for java-suspension, safepoints etc, 2800// within hotspot. Now there is a single use-case for this: 2801// - calling get_thread_pc() on the VMThread by the flat-profiler task 2802// that runs in the watcher thread. 2803// The remaining code is greatly simplified from the more general suspension 2804// code that used to be used. 2805// 2806// The protocol is quite simple: 2807// - suspend: 2808// - sends a signal to the target thread 2809// - polls the suspend state of the osthread using a yield loop 2810// - target thread signal handler (SR_handler) sets suspend state 2811// and blocks in sigsuspend until continued 2812// - resume: 2813// - sets target osthread state to continue 2814// - sends signal to end the sigsuspend loop in the SR_handler 2815// 2816// Note that the SR_lock plays no role in this suspend/resume protocol. 2817// 2818 2819static void resume_clear_context(OSThread *osthread) { 2820 osthread->set_ucontext(NULL); 2821 osthread->set_siginfo(NULL); 2822} 2823 2824static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2825 osthread->set_ucontext(context); 2826 osthread->set_siginfo(siginfo); 2827} 2828 2829// 2830// Handler function invoked when a thread's execution is suspended or 2831// resumed. We have to be careful that only async-safe functions are 2832// called here (Note: most pthread functions are not async safe and 2833// should be avoided.) 2834// 2835// Note: sigwait() is a more natural fit than sigsuspend() from an 2836// interface point of view, but sigwait() prevents the signal hander 2837// from being run. libpthread would get very confused by not having 2838// its signal handlers run and prevents sigwait()'s use with the 2839// mutex granting granting signal. 2840// 2841// Currently only ever called on the VMThread or JavaThread 2842// 2843static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2844 // Save and restore errno to avoid confusing native code with EINTR 2845 // after sigsuspend. 2846 int old_errno = errno; 2847 2848 Thread* thread = Thread::current(); 2849 OSThread* osthread = thread->osthread(); 2850 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2851 2852 os::SuspendResume::State current = osthread->sr.state(); 2853 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2854 suspend_save_context(osthread, siginfo, context); 2855 2856 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2857 os::SuspendResume::State state = osthread->sr.suspended(); 2858 if (state == os::SuspendResume::SR_SUSPENDED) { 2859 sigset_t suspend_set; // signals for sigsuspend() 2860 2861 // get current set of blocked signals and unblock resume signal 2862 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2863 sigdelset(&suspend_set, SR_signum); 2864 2865 sr_semaphore.signal(); 2866 // wait here until we are resumed 2867 while (1) { 2868 sigsuspend(&suspend_set); 2869 2870 os::SuspendResume::State result = osthread->sr.running(); 2871 if (result == os::SuspendResume::SR_RUNNING) { 2872 sr_semaphore.signal(); 2873 break; 2874 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2875 ShouldNotReachHere(); 2876 } 2877 } 2878 2879 } else if (state == os::SuspendResume::SR_RUNNING) { 2880 // request was cancelled, continue 2881 } else { 2882 ShouldNotReachHere(); 2883 } 2884 2885 resume_clear_context(osthread); 2886 } else if (current == os::SuspendResume::SR_RUNNING) { 2887 // request was cancelled, continue 2888 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2889 // ignore 2890 } else { 2891 // ignore 2892 } 2893 2894 errno = old_errno; 2895} 2896 2897 2898static int SR_initialize() { 2899 struct sigaction act; 2900 char *s; 2901 /* Get signal number to use for suspend/resume */ 2902 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2903 int sig = ::strtol(s, 0, 10); 2904 if (sig > 0 || sig < NSIG) { 2905 SR_signum = sig; 2906 } 2907 } 2908 2909 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2910 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2911 2912 sigemptyset(&SR_sigset); 2913 sigaddset(&SR_sigset, SR_signum); 2914 2915 /* Set up signal handler for suspend/resume */ 2916 act.sa_flags = SA_RESTART|SA_SIGINFO; 2917 act.sa_handler = (void (*)(int)) SR_handler; 2918 2919 // SR_signum is blocked by default. 2920 // 4528190 - We also need to block pthread restart signal (32 on all 2921 // supported Bsd platforms). Note that BsdThreads need to block 2922 // this signal for all threads to work properly. So we don't have 2923 // to use hard-coded signal number when setting up the mask. 2924 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2925 2926 if (sigaction(SR_signum, &act, 0) == -1) { 2927 return -1; 2928 } 2929 2930 // Save signal flag 2931 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2932 return 0; 2933} 2934 2935static int sr_notify(OSThread* osthread) { 2936 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2937 assert_status(status == 0, status, "pthread_kill"); 2938 return status; 2939} 2940 2941// "Randomly" selected value for how long we want to spin 2942// before bailing out on suspending a thread, also how often 2943// we send a signal to a thread we want to resume 2944static const int RANDOMLY_LARGE_INTEGER = 1000000; 2945static const int RANDOMLY_LARGE_INTEGER2 = 100; 2946 2947// returns true on success and false on error - really an error is fatal 2948// but this seems the normal response to library errors 2949static bool do_suspend(OSThread* osthread) { 2950 assert(osthread->sr.is_running(), "thread should be running"); 2951 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2952 2953 // mark as suspended and send signal 2954 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2955 // failed to switch, state wasn't running? 2956 ShouldNotReachHere(); 2957 return false; 2958 } 2959 2960 if (sr_notify(osthread) != 0) { 2961 ShouldNotReachHere(); 2962 } 2963 2964 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2965 while (true) { 2966 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2967 break; 2968 } else { 2969 // timeout 2970 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2971 if (cancelled == os::SuspendResume::SR_RUNNING) { 2972 return false; 2973 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2974 // make sure that we consume the signal on the semaphore as well 2975 sr_semaphore.wait(); 2976 break; 2977 } else { 2978 ShouldNotReachHere(); 2979 return false; 2980 } 2981 } 2982 } 2983 2984 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2985 return true; 2986} 2987 2988static void do_resume(OSThread* osthread) { 2989 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2990 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2991 2992 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2993 // failed to switch to WAKEUP_REQUEST 2994 ShouldNotReachHere(); 2995 return; 2996 } 2997 2998 while (true) { 2999 if (sr_notify(osthread) == 0) { 3000 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 3001 if (osthread->sr.is_running()) { 3002 return; 3003 } 3004 } 3005 } else { 3006 ShouldNotReachHere(); 3007 } 3008 } 3009 3010 guarantee(osthread->sr.is_running(), "Must be running!"); 3011} 3012 3013//////////////////////////////////////////////////////////////////////////////// 3014// interrupt support 3015 3016void os::interrupt(Thread* thread) { 3017 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3018 "possibility of dangling Thread pointer"); 3019 3020 OSThread* osthread = thread->osthread(); 3021 3022 if (!osthread->interrupted()) { 3023 osthread->set_interrupted(true); 3024 // More than one thread can get here with the same value of osthread, 3025 // resulting in multiple notifications. We do, however, want the store 3026 // to interrupted() to be visible to other threads before we execute unpark(). 3027 OrderAccess::fence(); 3028 ParkEvent * const slp = thread->_SleepEvent ; 3029 if (slp != NULL) slp->unpark() ; 3030 } 3031 3032 // For JSR166. Unpark even if interrupt status already was set 3033 if (thread->is_Java_thread()) 3034 ((JavaThread*)thread)->parker()->unpark(); 3035 3036 ParkEvent * ev = thread->_ParkEvent ; 3037 if (ev != NULL) ev->unpark() ; 3038 3039} 3040 3041bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 3042 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3043 "possibility of dangling Thread pointer"); 3044 3045 OSThread* osthread = thread->osthread(); 3046 3047 bool interrupted = osthread->interrupted(); 3048 3049 if (interrupted && clear_interrupted) { 3050 osthread->set_interrupted(false); 3051 // consider thread->_SleepEvent->reset() ... optional optimization 3052 } 3053 3054 return interrupted; 3055} 3056 3057/////////////////////////////////////////////////////////////////////////////////// 3058// signal handling (except suspend/resume) 3059 3060// This routine may be used by user applications as a "hook" to catch signals. 3061// The user-defined signal handler must pass unrecognized signals to this 3062// routine, and if it returns true (non-zero), then the signal handler must 3063// return immediately. If the flag "abort_if_unrecognized" is true, then this 3064// routine will never retun false (zero), but instead will execute a VM panic 3065// routine kill the process. 3066// 3067// If this routine returns false, it is OK to call it again. This allows 3068// the user-defined signal handler to perform checks either before or after 3069// the VM performs its own checks. Naturally, the user code would be making 3070// a serious error if it tried to handle an exception (such as a null check 3071// or breakpoint) that the VM was generating for its own correct operation. 3072// 3073// This routine may recognize any of the following kinds of signals: 3074// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 3075// It should be consulted by handlers for any of those signals. 3076// 3077// The caller of this routine must pass in the three arguments supplied 3078// to the function referred to in the "sa_sigaction" (not the "sa_handler") 3079// field of the structure passed to sigaction(). This routine assumes that 3080// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 3081// 3082// Note that the VM will print warnings if it detects conflicting signal 3083// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 3084// 3085extern "C" JNIEXPORT int 3086JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 3087 void* ucontext, int abort_if_unrecognized); 3088 3089void signalHandler(int sig, siginfo_t* info, void* uc) { 3090 assert(info != NULL && uc != NULL, "it must be old kernel"); 3091 int orig_errno = errno; // Preserve errno value over signal handler. 3092 JVM_handle_bsd_signal(sig, info, uc, true); 3093 errno = orig_errno; 3094} 3095 3096 3097// This boolean allows users to forward their own non-matching signals 3098// to JVM_handle_bsd_signal, harmlessly. 3099bool os::Bsd::signal_handlers_are_installed = false; 3100 3101// For signal-chaining 3102struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3103unsigned int os::Bsd::sigs = 0; 3104bool os::Bsd::libjsig_is_loaded = false; 3105typedef struct sigaction *(*get_signal_t)(int); 3106get_signal_t os::Bsd::get_signal_action = NULL; 3107 3108struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3109 struct sigaction *actp = NULL; 3110 3111 if (libjsig_is_loaded) { 3112 // Retrieve the old signal handler from libjsig 3113 actp = (*get_signal_action)(sig); 3114 } 3115 if (actp == NULL) { 3116 // Retrieve the preinstalled signal handler from jvm 3117 actp = get_preinstalled_handler(sig); 3118 } 3119 3120 return actp; 3121} 3122 3123static bool call_chained_handler(struct sigaction *actp, int sig, 3124 siginfo_t *siginfo, void *context) { 3125 // Call the old signal handler 3126 if (actp->sa_handler == SIG_DFL) { 3127 // It's more reasonable to let jvm treat it as an unexpected exception 3128 // instead of taking the default action. 3129 return false; 3130 } else if (actp->sa_handler != SIG_IGN) { 3131 if ((actp->sa_flags & SA_NODEFER) == 0) { 3132 // automaticlly block the signal 3133 sigaddset(&(actp->sa_mask), sig); 3134 } 3135 3136 sa_handler_t hand; 3137 sa_sigaction_t sa; 3138 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3139 // retrieve the chained handler 3140 if (siginfo_flag_set) { 3141 sa = actp->sa_sigaction; 3142 } else { 3143 hand = actp->sa_handler; 3144 } 3145 3146 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3147 actp->sa_handler = SIG_DFL; 3148 } 3149 3150 // try to honor the signal mask 3151 sigset_t oset; 3152 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3153 3154 // call into the chained handler 3155 if (siginfo_flag_set) { 3156 (*sa)(sig, siginfo, context); 3157 } else { 3158 (*hand)(sig); 3159 } 3160 3161 // restore the signal mask 3162 pthread_sigmask(SIG_SETMASK, &oset, 0); 3163 } 3164 // Tell jvm's signal handler the signal is taken care of. 3165 return true; 3166} 3167 3168bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3169 bool chained = false; 3170 // signal-chaining 3171 if (UseSignalChaining) { 3172 struct sigaction *actp = get_chained_signal_action(sig); 3173 if (actp != NULL) { 3174 chained = call_chained_handler(actp, sig, siginfo, context); 3175 } 3176 } 3177 return chained; 3178} 3179 3180struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3181 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 3182 return &sigact[sig]; 3183 } 3184 return NULL; 3185} 3186 3187void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3188 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3189 sigact[sig] = oldAct; 3190 sigs |= (unsigned int)1 << sig; 3191} 3192 3193// for diagnostic 3194int os::Bsd::sigflags[MAXSIGNUM]; 3195 3196int os::Bsd::get_our_sigflags(int sig) { 3197 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3198 return sigflags[sig]; 3199} 3200 3201void os::Bsd::set_our_sigflags(int sig, int flags) { 3202 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3203 sigflags[sig] = flags; 3204} 3205 3206void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3207 // Check for overwrite. 3208 struct sigaction oldAct; 3209 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3210 3211 void* oldhand = oldAct.sa_sigaction 3212 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3213 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3214 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3215 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3216 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3217 if (AllowUserSignalHandlers || !set_installed) { 3218 // Do not overwrite; user takes responsibility to forward to us. 3219 return; 3220 } else if (UseSignalChaining) { 3221 // save the old handler in jvm 3222 save_preinstalled_handler(sig, oldAct); 3223 // libjsig also interposes the sigaction() call below and saves the 3224 // old sigaction on it own. 3225 } else { 3226 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3227 "%#lx for signal %d.", (long)oldhand, sig)); 3228 } 3229 } 3230 3231 struct sigaction sigAct; 3232 sigfillset(&(sigAct.sa_mask)); 3233 sigAct.sa_handler = SIG_DFL; 3234 if (!set_installed) { 3235 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3236 } else { 3237 sigAct.sa_sigaction = signalHandler; 3238 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3239 } 3240#if __APPLE__ 3241 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3242 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3243 // if the signal handler declares it will handle it on alternate stack. 3244 // Notice we only declare we will handle it on alt stack, but we are not 3245 // actually going to use real alt stack - this is just a workaround. 3246 // Please see ux_exception.c, method catch_mach_exception_raise for details 3247 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3248 if (sig == SIGSEGV) { 3249 sigAct.sa_flags |= SA_ONSTACK; 3250 } 3251#endif 3252 3253 // Save flags, which are set by ours 3254 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3255 sigflags[sig] = sigAct.sa_flags; 3256 3257 int ret = sigaction(sig, &sigAct, &oldAct); 3258 assert(ret == 0, "check"); 3259 3260 void* oldhand2 = oldAct.sa_sigaction 3261 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3262 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3263 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3264} 3265 3266// install signal handlers for signals that HotSpot needs to 3267// handle in order to support Java-level exception handling. 3268 3269void os::Bsd::install_signal_handlers() { 3270 if (!signal_handlers_are_installed) { 3271 signal_handlers_are_installed = true; 3272 3273 // signal-chaining 3274 typedef void (*signal_setting_t)(); 3275 signal_setting_t begin_signal_setting = NULL; 3276 signal_setting_t end_signal_setting = NULL; 3277 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3278 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3279 if (begin_signal_setting != NULL) { 3280 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3281 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3282 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3283 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3284 libjsig_is_loaded = true; 3285 assert(UseSignalChaining, "should enable signal-chaining"); 3286 } 3287 if (libjsig_is_loaded) { 3288 // Tell libjsig jvm is setting signal handlers 3289 (*begin_signal_setting)(); 3290 } 3291 3292 set_signal_handler(SIGSEGV, true); 3293 set_signal_handler(SIGPIPE, true); 3294 set_signal_handler(SIGBUS, true); 3295 set_signal_handler(SIGILL, true); 3296 set_signal_handler(SIGFPE, true); 3297 set_signal_handler(SIGXFSZ, true); 3298 3299#if defined(__APPLE__) 3300 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3301 // signals caught and handled by the JVM. To work around this, we reset the mach task 3302 // signal handler that's placed on our process by CrashReporter. This disables 3303 // CrashReporter-based reporting. 3304 // 3305 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3306 // on caught fatal signals. 3307 // 3308 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3309 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3310 // exception handling, while leaving the standard BSD signal handlers functional. 3311 kern_return_t kr; 3312 kr = task_set_exception_ports(mach_task_self(), 3313 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3314 MACH_PORT_NULL, 3315 EXCEPTION_STATE_IDENTITY, 3316 MACHINE_THREAD_STATE); 3317 3318 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3319#endif 3320 3321 if (libjsig_is_loaded) { 3322 // Tell libjsig jvm finishes setting signal handlers 3323 (*end_signal_setting)(); 3324 } 3325 3326 // We don't activate signal checker if libjsig is in place, we trust ourselves 3327 // and if UserSignalHandler is installed all bets are off 3328 if (CheckJNICalls) { 3329 if (libjsig_is_loaded) { 3330 if (PrintJNIResolving) { 3331 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3332 } 3333 check_signals = false; 3334 } 3335 if (AllowUserSignalHandlers) { 3336 if (PrintJNIResolving) { 3337 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3338 } 3339 check_signals = false; 3340 } 3341 } 3342 } 3343} 3344 3345 3346///// 3347// glibc on Bsd platform uses non-documented flag 3348// to indicate, that some special sort of signal 3349// trampoline is used. 3350// We will never set this flag, and we should 3351// ignore this flag in our diagnostic 3352#ifdef SIGNIFICANT_SIGNAL_MASK 3353#undef SIGNIFICANT_SIGNAL_MASK 3354#endif 3355#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3356 3357static const char* get_signal_handler_name(address handler, 3358 char* buf, int buflen) { 3359 int offset; 3360 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3361 if (found) { 3362 // skip directory names 3363 const char *p1, *p2; 3364 p1 = buf; 3365 size_t len = strlen(os::file_separator()); 3366 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3367 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3368 } else { 3369 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3370 } 3371 return buf; 3372} 3373 3374static void print_signal_handler(outputStream* st, int sig, 3375 char* buf, size_t buflen) { 3376 struct sigaction sa; 3377 3378 sigaction(sig, NULL, &sa); 3379 3380 // See comment for SIGNIFICANT_SIGNAL_MASK define 3381 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3382 3383 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3384 3385 address handler = (sa.sa_flags & SA_SIGINFO) 3386 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3387 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3388 3389 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3390 st->print("SIG_DFL"); 3391 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3392 st->print("SIG_IGN"); 3393 } else { 3394 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3395 } 3396 3397 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask); 3398 3399 address rh = VMError::get_resetted_sighandler(sig); 3400 // May be, handler was resetted by VMError? 3401 if(rh != NULL) { 3402 handler = rh; 3403 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3404 } 3405 3406 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags); 3407 3408 // Check: is it our handler? 3409 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3410 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3411 // It is our signal handler 3412 // check for flags, reset system-used one! 3413 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3414 st->print( 3415 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3416 os::Bsd::get_our_sigflags(sig)); 3417 } 3418 } 3419 st->cr(); 3420} 3421 3422 3423#define DO_SIGNAL_CHECK(sig) \ 3424 if (!sigismember(&check_signal_done, sig)) \ 3425 os::Bsd::check_signal_handler(sig) 3426 3427// This method is a periodic task to check for misbehaving JNI applications 3428// under CheckJNI, we can add any periodic checks here 3429 3430void os::run_periodic_checks() { 3431 3432 if (check_signals == false) return; 3433 3434 // SEGV and BUS if overridden could potentially prevent 3435 // generation of hs*.log in the event of a crash, debugging 3436 // such a case can be very challenging, so we absolutely 3437 // check the following for a good measure: 3438 DO_SIGNAL_CHECK(SIGSEGV); 3439 DO_SIGNAL_CHECK(SIGILL); 3440 DO_SIGNAL_CHECK(SIGFPE); 3441 DO_SIGNAL_CHECK(SIGBUS); 3442 DO_SIGNAL_CHECK(SIGPIPE); 3443 DO_SIGNAL_CHECK(SIGXFSZ); 3444 3445 3446 // ReduceSignalUsage allows the user to override these handlers 3447 // see comments at the very top and jvm_solaris.h 3448 if (!ReduceSignalUsage) { 3449 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3450 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3451 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3452 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3453 } 3454 3455 DO_SIGNAL_CHECK(SR_signum); 3456 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3457} 3458 3459typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3460 3461static os_sigaction_t os_sigaction = NULL; 3462 3463void os::Bsd::check_signal_handler(int sig) { 3464 char buf[O_BUFLEN]; 3465 address jvmHandler = NULL; 3466 3467 3468 struct sigaction act; 3469 if (os_sigaction == NULL) { 3470 // only trust the default sigaction, in case it has been interposed 3471 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3472 if (os_sigaction == NULL) return; 3473 } 3474 3475 os_sigaction(sig, (struct sigaction*)NULL, &act); 3476 3477 3478 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3479 3480 address thisHandler = (act.sa_flags & SA_SIGINFO) 3481 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3482 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 3483 3484 3485 switch(sig) { 3486 case SIGSEGV: 3487 case SIGBUS: 3488 case SIGFPE: 3489 case SIGPIPE: 3490 case SIGILL: 3491 case SIGXFSZ: 3492 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3493 break; 3494 3495 case SHUTDOWN1_SIGNAL: 3496 case SHUTDOWN2_SIGNAL: 3497 case SHUTDOWN3_SIGNAL: 3498 case BREAK_SIGNAL: 3499 jvmHandler = (address)user_handler(); 3500 break; 3501 3502 case INTERRUPT_SIGNAL: 3503 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3504 break; 3505 3506 default: 3507 if (sig == SR_signum) { 3508 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3509 } else { 3510 return; 3511 } 3512 break; 3513 } 3514 3515 if (thisHandler != jvmHandler) { 3516 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3517 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3518 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3519 // No need to check this sig any longer 3520 sigaddset(&check_signal_done, sig); 3521 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3522 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3523 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3524 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3525 // No need to check this sig any longer 3526 sigaddset(&check_signal_done, sig); 3527 } 3528 3529 // Dump all the signal 3530 if (sigismember(&check_signal_done, sig)) { 3531 print_signal_handlers(tty, buf, O_BUFLEN); 3532 } 3533} 3534 3535extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3536 3537extern bool signal_name(int signo, char* buf, size_t len); 3538 3539const char* os::exception_name(int exception_code, char* buf, size_t size) { 3540 if (0 < exception_code && exception_code <= SIGRTMAX) { 3541 // signal 3542 if (!signal_name(exception_code, buf, size)) { 3543 jio_snprintf(buf, size, "SIG%d", exception_code); 3544 } 3545 return buf; 3546 } else { 3547 return NULL; 3548 } 3549} 3550 3551// this is called _before_ the most of global arguments have been parsed 3552void os::init(void) { 3553 char dummy; /* used to get a guess on initial stack address */ 3554// first_hrtime = gethrtime(); 3555 3556 // With BsdThreads the JavaMain thread pid (primordial thread) 3557 // is different than the pid of the java launcher thread. 3558 // So, on Bsd, the launcher thread pid is passed to the VM 3559 // via the sun.java.launcher.pid property. 3560 // Use this property instead of getpid() if it was correctly passed. 3561 // See bug 6351349. 3562 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3563 3564 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3565 3566 clock_tics_per_sec = CLK_TCK; 3567 3568 init_random(1234567); 3569 3570 ThreadCritical::initialize(); 3571 3572 Bsd::set_page_size(getpagesize()); 3573 if (Bsd::page_size() == -1) { 3574 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3575 strerror(errno))); 3576 } 3577 init_page_sizes((size_t) Bsd::page_size()); 3578 3579 Bsd::initialize_system_info(); 3580 3581 // main_thread points to the aboriginal thread 3582 Bsd::_main_thread = pthread_self(); 3583 3584 Bsd::clock_init(); 3585 initial_time_count = os::elapsed_counter(); 3586 3587#ifdef __APPLE__ 3588 // XXXDARWIN 3589 // Work around the unaligned VM callbacks in hotspot's 3590 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3591 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3592 // alignment when doing symbol lookup. To work around this, we force early 3593 // binding of all symbols now, thus binding when alignment is known-good. 3594 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3595#endif 3596} 3597 3598// To install functions for atexit system call 3599extern "C" { 3600 static void perfMemory_exit_helper() { 3601 perfMemory_exit(); 3602 } 3603} 3604 3605// this is called _after_ the global arguments have been parsed 3606jint os::init_2(void) 3607{ 3608 // Allocate a single page and mark it as readable for safepoint polling 3609 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3610 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 3611 3612 os::set_polling_page( polling_page ); 3613 3614#ifndef PRODUCT 3615 if(Verbose && PrintMiscellaneous) 3616 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3617#endif 3618 3619 if (!UseMembar) { 3620 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3621 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3622 os::set_memory_serialize_page( mem_serialize_page ); 3623 3624#ifndef PRODUCT 3625 if(Verbose && PrintMiscellaneous) 3626 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3627#endif 3628 } 3629 3630 // initialize suspend/resume support - must do this before signal_sets_init() 3631 if (SR_initialize() != 0) { 3632 perror("SR_initialize failed"); 3633 return JNI_ERR; 3634 } 3635 3636 Bsd::signal_sets_init(); 3637 Bsd::install_signal_handlers(); 3638 3639 // Check minimum allowable stack size for thread creation and to initialize 3640 // the java system classes, including StackOverflowError - depends on page 3641 // size. Add a page for compiler2 recursion in main thread. 3642 // Add in 2*BytesPerWord times page size to account for VM stack during 3643 // class initialization depending on 32 or 64 bit VM. 3644 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3645 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3646 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3647 3648 size_t threadStackSizeInBytes = ThreadStackSize * K; 3649 if (threadStackSizeInBytes != 0 && 3650 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3651 tty->print_cr("\nThe stack size specified is too small, " 3652 "Specify at least %dk", 3653 os::Bsd::min_stack_allowed/ K); 3654 return JNI_ERR; 3655 } 3656 3657 // Make the stack size a multiple of the page size so that 3658 // the yellow/red zones can be guarded. 3659 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3660 vm_page_size())); 3661 3662 if (MaxFDLimit) { 3663 // set the number of file descriptors to max. print out error 3664 // if getrlimit/setrlimit fails but continue regardless. 3665 struct rlimit nbr_files; 3666 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3667 if (status != 0) { 3668 if (PrintMiscellaneous && (Verbose || WizardMode)) 3669 perror("os::init_2 getrlimit failed"); 3670 } else { 3671 nbr_files.rlim_cur = nbr_files.rlim_max; 3672 3673#ifdef __APPLE__ 3674 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3675 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3676 // be used instead 3677 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3678#endif 3679 3680 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3681 if (status != 0) { 3682 if (PrintMiscellaneous && (Verbose || WizardMode)) 3683 perror("os::init_2 setrlimit failed"); 3684 } 3685 } 3686 } 3687 3688 // at-exit methods are called in the reverse order of their registration. 3689 // atexit functions are called on return from main or as a result of a 3690 // call to exit(3C). There can be only 32 of these functions registered 3691 // and atexit() does not set errno. 3692 3693 if (PerfAllowAtExitRegistration) { 3694 // only register atexit functions if PerfAllowAtExitRegistration is set. 3695 // atexit functions can be delayed until process exit time, which 3696 // can be problematic for embedded VM situations. Embedded VMs should 3697 // call DestroyJavaVM() to assure that VM resources are released. 3698 3699 // note: perfMemory_exit_helper atexit function may be removed in 3700 // the future if the appropriate cleanup code can be added to the 3701 // VM_Exit VMOperation's doit method. 3702 if (atexit(perfMemory_exit_helper) != 0) { 3703 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3704 } 3705 } 3706 3707 // initialize thread priority policy 3708 prio_init(); 3709 3710#ifdef __APPLE__ 3711 // dynamically link to objective c gc registration 3712 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3713 if (handleLibObjc != NULL) { 3714 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3715 } 3716#endif 3717 3718 return JNI_OK; 3719} 3720 3721// this is called at the end of vm_initialization 3722void os::init_3(void) { } 3723 3724// Mark the polling page as unreadable 3725void os::make_polling_page_unreadable(void) { 3726 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 3727 fatal("Could not disable polling page"); 3728}; 3729 3730// Mark the polling page as readable 3731void os::make_polling_page_readable(void) { 3732 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3733 fatal("Could not enable polling page"); 3734 } 3735}; 3736 3737int os::active_processor_count() { 3738 return _processor_count; 3739} 3740 3741void os::set_native_thread_name(const char *name) { 3742#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3743 // This is only supported in Snow Leopard and beyond 3744 if (name != NULL) { 3745 // Add a "Java: " prefix to the name 3746 char buf[MAXTHREADNAMESIZE]; 3747 snprintf(buf, sizeof(buf), "Java: %s", name); 3748 pthread_setname_np(buf); 3749 } 3750#endif 3751} 3752 3753bool os::distribute_processes(uint length, uint* distribution) { 3754 // Not yet implemented. 3755 return false; 3756} 3757 3758bool os::bind_to_processor(uint processor_id) { 3759 // Not yet implemented. 3760 return false; 3761} 3762 3763void os::SuspendedThreadTask::internal_do_task() { 3764 if (do_suspend(_thread->osthread())) { 3765 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3766 do_task(context); 3767 do_resume(_thread->osthread()); 3768 } 3769} 3770 3771/// 3772class PcFetcher : public os::SuspendedThreadTask { 3773public: 3774 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3775 ExtendedPC result(); 3776protected: 3777 void do_task(const os::SuspendedThreadTaskContext& context); 3778private: 3779 ExtendedPC _epc; 3780}; 3781 3782ExtendedPC PcFetcher::result() { 3783 guarantee(is_done(), "task is not done yet."); 3784 return _epc; 3785} 3786 3787void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3788 Thread* thread = context.thread(); 3789 OSThread* osthread = thread->osthread(); 3790 if (osthread->ucontext() != NULL) { 3791 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3792 } else { 3793 // NULL context is unexpected, double-check this is the VMThread 3794 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3795 } 3796} 3797 3798// Suspends the target using the signal mechanism and then grabs the PC before 3799// resuming the target. Used by the flat-profiler only 3800ExtendedPC os::get_thread_pc(Thread* thread) { 3801 // Make sure that it is called by the watcher for the VMThread 3802 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3803 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3804 3805 PcFetcher fetcher(thread); 3806 fetcher.run(); 3807 return fetcher.result(); 3808} 3809 3810int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3811{ 3812 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3813} 3814 3815//////////////////////////////////////////////////////////////////////////////// 3816// debug support 3817 3818bool os::find(address addr, outputStream* st) { 3819 Dl_info dlinfo; 3820 memset(&dlinfo, 0, sizeof(dlinfo)); 3821 if (dladdr(addr, &dlinfo) != 0) { 3822 st->print(PTR_FORMAT ": ", addr); 3823 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3824 st->print("%s+%#x", dlinfo.dli_sname, 3825 addr - (intptr_t)dlinfo.dli_saddr); 3826 } else if (dlinfo.dli_fbase != NULL) { 3827 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3828 } else { 3829 st->print("<absolute address>"); 3830 } 3831 if (dlinfo.dli_fname != NULL) { 3832 st->print(" in %s", dlinfo.dli_fname); 3833 } 3834 if (dlinfo.dli_fbase != NULL) { 3835 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3836 } 3837 st->cr(); 3838 3839 if (Verbose) { 3840 // decode some bytes around the PC 3841 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3842 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3843 address lowest = (address) dlinfo.dli_sname; 3844 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3845 if (begin < lowest) begin = lowest; 3846 Dl_info dlinfo2; 3847 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3848 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3849 end = (address) dlinfo2.dli_saddr; 3850 Disassembler::decode(begin, end, st); 3851 } 3852 return true; 3853 } 3854 return false; 3855} 3856 3857//////////////////////////////////////////////////////////////////////////////// 3858// misc 3859 3860// This does not do anything on Bsd. This is basically a hook for being 3861// able to use structured exception handling (thread-local exception filters) 3862// on, e.g., Win32. 3863void 3864os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3865 JavaCallArguments* args, Thread* thread) { 3866 f(value, method, args, thread); 3867} 3868 3869void os::print_statistics() { 3870} 3871 3872int os::message_box(const char* title, const char* message) { 3873 int i; 3874 fdStream err(defaultStream::error_fd()); 3875 for (i = 0; i < 78; i++) err.print_raw("="); 3876 err.cr(); 3877 err.print_raw_cr(title); 3878 for (i = 0; i < 78; i++) err.print_raw("-"); 3879 err.cr(); 3880 err.print_raw_cr(message); 3881 for (i = 0; i < 78; i++) err.print_raw("="); 3882 err.cr(); 3883 3884 char buf[16]; 3885 // Prevent process from exiting upon "read error" without consuming all CPU 3886 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3887 3888 return buf[0] == 'y' || buf[0] == 'Y'; 3889} 3890 3891int os::stat(const char *path, struct stat *sbuf) { 3892 char pathbuf[MAX_PATH]; 3893 if (strlen(path) > MAX_PATH - 1) { 3894 errno = ENAMETOOLONG; 3895 return -1; 3896 } 3897 os::native_path(strcpy(pathbuf, path)); 3898 return ::stat(pathbuf, sbuf); 3899} 3900 3901bool os::check_heap(bool force) { 3902 return true; 3903} 3904 3905int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 3906 return ::vsnprintf(buf, count, format, args); 3907} 3908 3909// Is a (classpath) directory empty? 3910bool os::dir_is_empty(const char* path) { 3911 DIR *dir = NULL; 3912 struct dirent *ptr; 3913 3914 dir = opendir(path); 3915 if (dir == NULL) return true; 3916 3917 /* Scan the directory */ 3918 bool result = true; 3919 char buf[sizeof(struct dirent) + MAX_PATH]; 3920 while (result && (ptr = ::readdir(dir)) != NULL) { 3921 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3922 result = false; 3923 } 3924 } 3925 closedir(dir); 3926 return result; 3927} 3928 3929// This code originates from JDK's sysOpen and open64_w 3930// from src/solaris/hpi/src/system_md.c 3931 3932#ifndef O_DELETE 3933#define O_DELETE 0x10000 3934#endif 3935 3936// Open a file. Unlink the file immediately after open returns 3937// if the specified oflag has the O_DELETE flag set. 3938// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3939 3940int os::open(const char *path, int oflag, int mode) { 3941 3942 if (strlen(path) > MAX_PATH - 1) { 3943 errno = ENAMETOOLONG; 3944 return -1; 3945 } 3946 int fd; 3947 int o_delete = (oflag & O_DELETE); 3948 oflag = oflag & ~O_DELETE; 3949 3950 fd = ::open(path, oflag, mode); 3951 if (fd == -1) return -1; 3952 3953 //If the open succeeded, the file might still be a directory 3954 { 3955 struct stat buf; 3956 int ret = ::fstat(fd, &buf); 3957 int st_mode = buf.st_mode; 3958 3959 if (ret != -1) { 3960 if ((st_mode & S_IFMT) == S_IFDIR) { 3961 errno = EISDIR; 3962 ::close(fd); 3963 return -1; 3964 } 3965 } else { 3966 ::close(fd); 3967 return -1; 3968 } 3969 } 3970 3971 /* 3972 * All file descriptors that are opened in the JVM and not 3973 * specifically destined for a subprocess should have the 3974 * close-on-exec flag set. If we don't set it, then careless 3rd 3975 * party native code might fork and exec without closing all 3976 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3977 * UNIXProcess.c), and this in turn might: 3978 * 3979 * - cause end-of-file to fail to be detected on some file 3980 * descriptors, resulting in mysterious hangs, or 3981 * 3982 * - might cause an fopen in the subprocess to fail on a system 3983 * suffering from bug 1085341. 3984 * 3985 * (Yes, the default setting of the close-on-exec flag is a Unix 3986 * design flaw) 3987 * 3988 * See: 3989 * 1085341: 32-bit stdio routines should support file descriptors >255 3990 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3991 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3992 */ 3993#ifdef FD_CLOEXEC 3994 { 3995 int flags = ::fcntl(fd, F_GETFD); 3996 if (flags != -1) 3997 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3998 } 3999#endif 4000 4001 if (o_delete != 0) { 4002 ::unlink(path); 4003 } 4004 return fd; 4005} 4006 4007 4008// create binary file, rewriting existing file if required 4009int os::create_binary_file(const char* path, bool rewrite_existing) { 4010 int oflags = O_WRONLY | O_CREAT; 4011 if (!rewrite_existing) { 4012 oflags |= O_EXCL; 4013 } 4014 return ::open(path, oflags, S_IREAD | S_IWRITE); 4015} 4016 4017// return current position of file pointer 4018jlong os::current_file_offset(int fd) { 4019 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 4020} 4021 4022// move file pointer to the specified offset 4023jlong os::seek_to_file_offset(int fd, jlong offset) { 4024 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 4025} 4026 4027// This code originates from JDK's sysAvailable 4028// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 4029 4030int os::available(int fd, jlong *bytes) { 4031 jlong cur, end; 4032 int mode; 4033 struct stat buf; 4034 4035 if (::fstat(fd, &buf) >= 0) { 4036 mode = buf.st_mode; 4037 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 4038 /* 4039 * XXX: is the following call interruptible? If so, this might 4040 * need to go through the INTERRUPT_IO() wrapper as for other 4041 * blocking, interruptible calls in this file. 4042 */ 4043 int n; 4044 if (::ioctl(fd, FIONREAD, &n) >= 0) { 4045 *bytes = n; 4046 return 1; 4047 } 4048 } 4049 } 4050 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 4051 return 0; 4052 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 4053 return 0; 4054 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 4055 return 0; 4056 } 4057 *bytes = end - cur; 4058 return 1; 4059} 4060 4061int os::socket_available(int fd, jint *pbytes) { 4062 if (fd < 0) 4063 return OS_OK; 4064 4065 int ret; 4066 4067 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 4068 4069 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 4070 // is expected to return 0 on failure and 1 on success to the jdk. 4071 4072 return (ret == OS_ERR) ? 0 : 1; 4073} 4074 4075// Map a block of memory. 4076char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 4077 char *addr, size_t bytes, bool read_only, 4078 bool allow_exec) { 4079 int prot; 4080 int flags; 4081 4082 if (read_only) { 4083 prot = PROT_READ; 4084 flags = MAP_SHARED; 4085 } else { 4086 prot = PROT_READ | PROT_WRITE; 4087 flags = MAP_PRIVATE; 4088 } 4089 4090 if (allow_exec) { 4091 prot |= PROT_EXEC; 4092 } 4093 4094 if (addr != NULL) { 4095 flags |= MAP_FIXED; 4096 } 4097 4098 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4099 fd, file_offset); 4100 if (mapped_address == MAP_FAILED) { 4101 return NULL; 4102 } 4103 return mapped_address; 4104} 4105 4106 4107// Remap a block of memory. 4108char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4109 char *addr, size_t bytes, bool read_only, 4110 bool allow_exec) { 4111 // same as map_memory() on this OS 4112 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4113 allow_exec); 4114} 4115 4116 4117// Unmap a block of memory. 4118bool os::pd_unmap_memory(char* addr, size_t bytes) { 4119 return munmap(addr, bytes) == 0; 4120} 4121 4122// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4123// are used by JVM M&M and JVMTI to get user+sys or user CPU time 4124// of a thread. 4125// 4126// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4127// the fast estimate available on the platform. 4128 4129jlong os::current_thread_cpu_time() { 4130#ifdef __APPLE__ 4131 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4132#else 4133 Unimplemented(); 4134 return 0; 4135#endif 4136} 4137 4138jlong os::thread_cpu_time(Thread* thread) { 4139#ifdef __APPLE__ 4140 return os::thread_cpu_time(thread, true /* user + sys */); 4141#else 4142 Unimplemented(); 4143 return 0; 4144#endif 4145} 4146 4147jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4148#ifdef __APPLE__ 4149 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4150#else 4151 Unimplemented(); 4152 return 0; 4153#endif 4154} 4155 4156jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4157#ifdef __APPLE__ 4158 struct thread_basic_info tinfo; 4159 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4160 kern_return_t kr; 4161 thread_t mach_thread; 4162 4163 mach_thread = thread->osthread()->thread_id(); 4164 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4165 if (kr != KERN_SUCCESS) 4166 return -1; 4167 4168 if (user_sys_cpu_time) { 4169 jlong nanos; 4170 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4171 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4172 return nanos; 4173 } else { 4174 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4175 } 4176#else 4177 Unimplemented(); 4178 return 0; 4179#endif 4180} 4181 4182 4183void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4184 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4185 info_ptr->may_skip_backward = false; // elapsed time not wall time 4186 info_ptr->may_skip_forward = false; // elapsed time not wall time 4187 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4188} 4189 4190void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4191 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4192 info_ptr->may_skip_backward = false; // elapsed time not wall time 4193 info_ptr->may_skip_forward = false; // elapsed time not wall time 4194 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4195} 4196 4197bool os::is_thread_cpu_time_supported() { 4198#ifdef __APPLE__ 4199 return true; 4200#else 4201 return false; 4202#endif 4203} 4204 4205// System loadavg support. Returns -1 if load average cannot be obtained. 4206// Bsd doesn't yet have a (official) notion of processor sets, 4207// so just return the system wide load average. 4208int os::loadavg(double loadavg[], int nelem) { 4209 return ::getloadavg(loadavg, nelem); 4210} 4211 4212void os::pause() { 4213 char filename[MAX_PATH]; 4214 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4215 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4216 } else { 4217 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4218 } 4219 4220 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4221 if (fd != -1) { 4222 struct stat buf; 4223 ::close(fd); 4224 while (::stat(filename, &buf) == 0) { 4225 (void)::poll(NULL, 0, 100); 4226 } 4227 } else { 4228 jio_fprintf(stderr, 4229 "Could not open pause file '%s', continuing immediately.\n", filename); 4230 } 4231} 4232 4233 4234// Refer to the comments in os_solaris.cpp park-unpark. 4235// 4236// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4237// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4238// For specifics regarding the bug see GLIBC BUGID 261237 : 4239// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4240// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4241// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4242// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4243// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4244// and monitorenter when we're using 1-0 locking. All those operations may result in 4245// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4246// of libpthread avoids the problem, but isn't practical. 4247// 4248// Possible remedies: 4249// 4250// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4251// This is palliative and probabilistic, however. If the thread is preempted 4252// between the call to compute_abstime() and pthread_cond_timedwait(), more 4253// than the minimum period may have passed, and the abstime may be stale (in the 4254// past) resultin in a hang. Using this technique reduces the odds of a hang 4255// but the JVM is still vulnerable, particularly on heavily loaded systems. 4256// 4257// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4258// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4259// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4260// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4261// thread. 4262// 4263// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4264// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4265// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4266// This also works well. In fact it avoids kernel-level scalability impediments 4267// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4268// timers in a graceful fashion. 4269// 4270// 4. When the abstime value is in the past it appears that control returns 4271// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4272// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4273// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4274// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4275// It may be possible to avoid reinitialization by checking the return 4276// value from pthread_cond_timedwait(). In addition to reinitializing the 4277// condvar we must establish the invariant that cond_signal() is only called 4278// within critical sections protected by the adjunct mutex. This prevents 4279// cond_signal() from "seeing" a condvar that's in the midst of being 4280// reinitialized or that is corrupt. Sadly, this invariant obviates the 4281// desirable signal-after-unlock optimization that avoids futile context switching. 4282// 4283// I'm also concerned that some versions of NTPL might allocate an auxilliary 4284// structure when a condvar is used or initialized. cond_destroy() would 4285// release the helper structure. Our reinitialize-after-timedwait fix 4286// put excessive stress on malloc/free and locks protecting the c-heap. 4287// 4288// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4289// It may be possible to refine (4) by checking the kernel and NTPL verisons 4290// and only enabling the work-around for vulnerable environments. 4291 4292// utility to compute the abstime argument to timedwait: 4293// millis is the relative timeout time 4294// abstime will be the absolute timeout time 4295// TODO: replace compute_abstime() with unpackTime() 4296 4297static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4298 if (millis < 0) millis = 0; 4299 struct timeval now; 4300 int status = gettimeofday(&now, NULL); 4301 assert(status == 0, "gettimeofday"); 4302 jlong seconds = millis / 1000; 4303 millis %= 1000; 4304 if (seconds > 50000000) { // see man cond_timedwait(3T) 4305 seconds = 50000000; 4306 } 4307 abstime->tv_sec = now.tv_sec + seconds; 4308 long usec = now.tv_usec + millis * 1000; 4309 if (usec >= 1000000) { 4310 abstime->tv_sec += 1; 4311 usec -= 1000000; 4312 } 4313 abstime->tv_nsec = usec * 1000; 4314 return abstime; 4315} 4316 4317 4318// Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 4319// Conceptually TryPark() should be equivalent to park(0). 4320 4321int os::PlatformEvent::TryPark() { 4322 for (;;) { 4323 const int v = _Event ; 4324 guarantee ((v == 0) || (v == 1), "invariant") ; 4325 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 4326 } 4327} 4328 4329void os::PlatformEvent::park() { // AKA "down()" 4330 // Invariant: Only the thread associated with the Event/PlatformEvent 4331 // may call park(). 4332 // TODO: assert that _Assoc != NULL or _Assoc == Self 4333 int v ; 4334 for (;;) { 4335 v = _Event ; 4336 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4337 } 4338 guarantee (v >= 0, "invariant") ; 4339 if (v == 0) { 4340 // Do this the hard way by blocking ... 4341 int status = pthread_mutex_lock(_mutex); 4342 assert_status(status == 0, status, "mutex_lock"); 4343 guarantee (_nParked == 0, "invariant") ; 4344 ++ _nParked ; 4345 while (_Event < 0) { 4346 status = pthread_cond_wait(_cond, _mutex); 4347 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4348 // Treat this the same as if the wait was interrupted 4349 if (status == ETIMEDOUT) { status = EINTR; } 4350 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4351 } 4352 -- _nParked ; 4353 4354 _Event = 0 ; 4355 status = pthread_mutex_unlock(_mutex); 4356 assert_status(status == 0, status, "mutex_unlock"); 4357 // Paranoia to ensure our locked and lock-free paths interact 4358 // correctly with each other. 4359 OrderAccess::fence(); 4360 } 4361 guarantee (_Event >= 0, "invariant") ; 4362} 4363 4364int os::PlatformEvent::park(jlong millis) { 4365 guarantee (_nParked == 0, "invariant") ; 4366 4367 int v ; 4368 for (;;) { 4369 v = _Event ; 4370 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4371 } 4372 guarantee (v >= 0, "invariant") ; 4373 if (v != 0) return OS_OK ; 4374 4375 // We do this the hard way, by blocking the thread. 4376 // Consider enforcing a minimum timeout value. 4377 struct timespec abst; 4378 compute_abstime(&abst, millis); 4379 4380 int ret = OS_TIMEOUT; 4381 int status = pthread_mutex_lock(_mutex); 4382 assert_status(status == 0, status, "mutex_lock"); 4383 guarantee (_nParked == 0, "invariant") ; 4384 ++_nParked ; 4385 4386 // Object.wait(timo) will return because of 4387 // (a) notification 4388 // (b) timeout 4389 // (c) thread.interrupt 4390 // 4391 // Thread.interrupt and object.notify{All} both call Event::set. 4392 // That is, we treat thread.interrupt as a special case of notification. 4393 // The underlying Solaris implementation, cond_timedwait, admits 4394 // spurious/premature wakeups, but the JLS/JVM spec prevents the 4395 // JVM from making those visible to Java code. As such, we must 4396 // filter out spurious wakeups. We assume all ETIME returns are valid. 4397 // 4398 // TODO: properly differentiate simultaneous notify+interrupt. 4399 // In that case, we should propagate the notify to another waiter. 4400 4401 while (_Event < 0) { 4402 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4403 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4404 pthread_cond_destroy (_cond); 4405 pthread_cond_init (_cond, NULL) ; 4406 } 4407 assert_status(status == 0 || status == EINTR || 4408 status == ETIMEDOUT, 4409 status, "cond_timedwait"); 4410 if (!FilterSpuriousWakeups) break ; // previous semantics 4411 if (status == ETIMEDOUT) break ; 4412 // We consume and ignore EINTR and spurious wakeups. 4413 } 4414 --_nParked ; 4415 if (_Event >= 0) { 4416 ret = OS_OK; 4417 } 4418 _Event = 0 ; 4419 status = pthread_mutex_unlock(_mutex); 4420 assert_status(status == 0, status, "mutex_unlock"); 4421 assert (_nParked == 0, "invariant") ; 4422 // Paranoia to ensure our locked and lock-free paths interact 4423 // correctly with each other. 4424 OrderAccess::fence(); 4425 return ret; 4426} 4427 4428void os::PlatformEvent::unpark() { 4429 // Transitions for _Event: 4430 // 0 :=> 1 4431 // 1 :=> 1 4432 // -1 :=> either 0 or 1; must signal target thread 4433 // That is, we can safely transition _Event from -1 to either 4434 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back 4435 // unpark() calls. 4436 // See also: "Semaphores in Plan 9" by Mullender & Cox 4437 // 4438 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4439 // that it will take two back-to-back park() calls for the owning 4440 // thread to block. This has the benefit of forcing a spurious return 4441 // from the first park() call after an unpark() call which will help 4442 // shake out uses of park() and unpark() without condition variables. 4443 4444 if (Atomic::xchg(1, &_Event) >= 0) return; 4445 4446 // Wait for the thread associated with the event to vacate 4447 int status = pthread_mutex_lock(_mutex); 4448 assert_status(status == 0, status, "mutex_lock"); 4449 int AnyWaiters = _nParked; 4450 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4451 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4452 AnyWaiters = 0; 4453 pthread_cond_signal(_cond); 4454 } 4455 status = pthread_mutex_unlock(_mutex); 4456 assert_status(status == 0, status, "mutex_unlock"); 4457 if (AnyWaiters != 0) { 4458 status = pthread_cond_signal(_cond); 4459 assert_status(status == 0, status, "cond_signal"); 4460 } 4461 4462 // Note that we signal() _after dropping the lock for "immortal" Events. 4463 // This is safe and avoids a common class of futile wakeups. In rare 4464 // circumstances this can cause a thread to return prematurely from 4465 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4466 // simply re-test the condition and re-park itself. 4467} 4468 4469 4470// JSR166 4471// ------------------------------------------------------- 4472 4473/* 4474 * The solaris and bsd implementations of park/unpark are fairly 4475 * conservative for now, but can be improved. They currently use a 4476 * mutex/condvar pair, plus a a count. 4477 * Park decrements count if > 0, else does a condvar wait. Unpark 4478 * sets count to 1 and signals condvar. Only one thread ever waits 4479 * on the condvar. Contention seen when trying to park implies that someone 4480 * is unparking you, so don't wait. And spurious returns are fine, so there 4481 * is no need to track notifications. 4482 */ 4483 4484#define MAX_SECS 100000000 4485/* 4486 * This code is common to bsd and solaris and will be moved to a 4487 * common place in dolphin. 4488 * 4489 * The passed in time value is either a relative time in nanoseconds 4490 * or an absolute time in milliseconds. Either way it has to be unpacked 4491 * into suitable seconds and nanoseconds components and stored in the 4492 * given timespec structure. 4493 * Given time is a 64-bit value and the time_t used in the timespec is only 4494 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4495 * overflow if times way in the future are given. Further on Solaris versions 4496 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4497 * number of seconds, in abstime, is less than current_time + 100,000,000. 4498 * As it will be 28 years before "now + 100000000" will overflow we can 4499 * ignore overflow and just impose a hard-limit on seconds using the value 4500 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4501 * years from "now". 4502 */ 4503 4504static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4505 assert (time > 0, "convertTime"); 4506 4507 struct timeval now; 4508 int status = gettimeofday(&now, NULL); 4509 assert(status == 0, "gettimeofday"); 4510 4511 time_t max_secs = now.tv_sec + MAX_SECS; 4512 4513 if (isAbsolute) { 4514 jlong secs = time / 1000; 4515 if (secs > max_secs) { 4516 absTime->tv_sec = max_secs; 4517 } 4518 else { 4519 absTime->tv_sec = secs; 4520 } 4521 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4522 } 4523 else { 4524 jlong secs = time / NANOSECS_PER_SEC; 4525 if (secs >= MAX_SECS) { 4526 absTime->tv_sec = max_secs; 4527 absTime->tv_nsec = 0; 4528 } 4529 else { 4530 absTime->tv_sec = now.tv_sec + secs; 4531 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4532 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4533 absTime->tv_nsec -= NANOSECS_PER_SEC; 4534 ++absTime->tv_sec; // note: this must be <= max_secs 4535 } 4536 } 4537 } 4538 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4539 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4540 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4541 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4542} 4543 4544void Parker::park(bool isAbsolute, jlong time) { 4545 // Ideally we'd do something useful while spinning, such 4546 // as calling unpackTime(). 4547 4548 // Optional fast-path check: 4549 // Return immediately if a permit is available. 4550 // We depend on Atomic::xchg() having full barrier semantics 4551 // since we are doing a lock-free update to _counter. 4552 if (Atomic::xchg(0, &_counter) > 0) return; 4553 4554 Thread* thread = Thread::current(); 4555 assert(thread->is_Java_thread(), "Must be JavaThread"); 4556 JavaThread *jt = (JavaThread *)thread; 4557 4558 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4559 // Check interrupt before trying to wait 4560 if (Thread::is_interrupted(thread, false)) { 4561 return; 4562 } 4563 4564 // Next, demultiplex/decode time arguments 4565 struct timespec absTime; 4566 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 4567 return; 4568 } 4569 if (time > 0) { 4570 unpackTime(&absTime, isAbsolute, time); 4571 } 4572 4573 4574 // Enter safepoint region 4575 // Beware of deadlocks such as 6317397. 4576 // The per-thread Parker:: mutex is a classic leaf-lock. 4577 // In particular a thread must never block on the Threads_lock while 4578 // holding the Parker:: mutex. If safepoints are pending both the 4579 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4580 ThreadBlockInVM tbivm(jt); 4581 4582 // Don't wait if cannot get lock since interference arises from 4583 // unblocking. Also. check interrupt before trying wait 4584 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4585 return; 4586 } 4587 4588 int status ; 4589 if (_counter > 0) { // no wait needed 4590 _counter = 0; 4591 status = pthread_mutex_unlock(_mutex); 4592 assert (status == 0, "invariant") ; 4593 // Paranoia to ensure our locked and lock-free paths interact 4594 // correctly with each other and Java-level accesses. 4595 OrderAccess::fence(); 4596 return; 4597 } 4598 4599#ifdef ASSERT 4600 // Don't catch signals while blocked; let the running threads have the signals. 4601 // (This allows a debugger to break into the running thread.) 4602 sigset_t oldsigs; 4603 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4604 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4605#endif 4606 4607 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4608 jt->set_suspend_equivalent(); 4609 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4610 4611 if (time == 0) { 4612 status = pthread_cond_wait (_cond, _mutex) ; 4613 } else { 4614 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 4615 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4616 pthread_cond_destroy (_cond) ; 4617 pthread_cond_init (_cond, NULL); 4618 } 4619 } 4620 assert_status(status == 0 || status == EINTR || 4621 status == ETIMEDOUT, 4622 status, "cond_timedwait"); 4623 4624#ifdef ASSERT 4625 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4626#endif 4627 4628 _counter = 0 ; 4629 status = pthread_mutex_unlock(_mutex) ; 4630 assert_status(status == 0, status, "invariant") ; 4631 // Paranoia to ensure our locked and lock-free paths interact 4632 // correctly with each other and Java-level accesses. 4633 OrderAccess::fence(); 4634 4635 // If externally suspended while waiting, re-suspend 4636 if (jt->handle_special_suspend_equivalent_condition()) { 4637 jt->java_suspend_self(); 4638 } 4639} 4640 4641void Parker::unpark() { 4642 int s, status ; 4643 status = pthread_mutex_lock(_mutex); 4644 assert (status == 0, "invariant") ; 4645 s = _counter; 4646 _counter = 1; 4647 if (s < 1) { 4648 if (WorkAroundNPTLTimedWaitHang) { 4649 status = pthread_cond_signal (_cond) ; 4650 assert (status == 0, "invariant") ; 4651 status = pthread_mutex_unlock(_mutex); 4652 assert (status == 0, "invariant") ; 4653 } else { 4654 status = pthread_mutex_unlock(_mutex); 4655 assert (status == 0, "invariant") ; 4656 status = pthread_cond_signal (_cond) ; 4657 assert (status == 0, "invariant") ; 4658 } 4659 } else { 4660 pthread_mutex_unlock(_mutex); 4661 assert (status == 0, "invariant") ; 4662 } 4663} 4664 4665 4666/* Darwin has no "environ" in a dynamic library. */ 4667#ifdef __APPLE__ 4668#include <crt_externs.h> 4669#define environ (*_NSGetEnviron()) 4670#else 4671extern char** environ; 4672#endif 4673 4674// Run the specified command in a separate process. Return its exit value, 4675// or -1 on failure (e.g. can't fork a new process). 4676// Unlike system(), this function can be called from signal handler. It 4677// doesn't block SIGINT et al. 4678int os::fork_and_exec(char* cmd) { 4679 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4680 4681 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4682 // pthread_atfork handlers and reset pthread library. All we need is a 4683 // separate process to execve. Make a direct syscall to fork process. 4684 // On IA64 there's no fork syscall, we have to use fork() and hope for 4685 // the best... 4686 pid_t pid = fork(); 4687 4688 if (pid < 0) { 4689 // fork failed 4690 return -1; 4691 4692 } else if (pid == 0) { 4693 // child process 4694 4695 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4696 // first to kill every thread on the thread list. Because this list is 4697 // not reset by fork() (see notes above), execve() will instead kill 4698 // every thread in the parent process. We know this is the only thread 4699 // in the new process, so make a system call directly. 4700 // IA64 should use normal execve() from glibc to match the glibc fork() 4701 // above. 4702 execve("/bin/sh", (char* const*)argv, environ); 4703 4704 // execve failed 4705 _exit(-1); 4706 4707 } else { 4708 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4709 // care about the actual exit code, for now. 4710 4711 int status; 4712 4713 // Wait for the child process to exit. This returns immediately if 4714 // the child has already exited. */ 4715 while (waitpid(pid, &status, 0) < 0) { 4716 switch (errno) { 4717 case ECHILD: return 0; 4718 case EINTR: break; 4719 default: return -1; 4720 } 4721 } 4722 4723 if (WIFEXITED(status)) { 4724 // The child exited normally; get its exit code. 4725 return WEXITSTATUS(status); 4726 } else if (WIFSIGNALED(status)) { 4727 // The child exited because of a signal 4728 // The best value to return is 0x80 + signal number, 4729 // because that is what all Unix shells do, and because 4730 // it allows callers to distinguish between process exit and 4731 // process death by signal. 4732 return 0x80 + WTERMSIG(status); 4733 } else { 4734 // Unknown exit code; pass it through 4735 return status; 4736 } 4737 } 4738} 4739 4740// is_headless_jre() 4741// 4742// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4743// in order to report if we are running in a headless jre 4744// 4745// Since JDK8 xawt/libmawt.so was moved into the same directory 4746// as libawt.so, and renamed libawt_xawt.so 4747// 4748bool os::is_headless_jre() { 4749#ifdef __APPLE__ 4750 // We no longer build headless-only on Mac OS X 4751 return false; 4752#else 4753 struct stat statbuf; 4754 char buf[MAXPATHLEN]; 4755 char libmawtpath[MAXPATHLEN]; 4756 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4757 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4758 char *p; 4759 4760 // Get path to libjvm.so 4761 os::jvm_path(buf, sizeof(buf)); 4762 4763 // Get rid of libjvm.so 4764 p = strrchr(buf, '/'); 4765 if (p == NULL) return false; 4766 else *p = '\0'; 4767 4768 // Get rid of client or server 4769 p = strrchr(buf, '/'); 4770 if (p == NULL) return false; 4771 else *p = '\0'; 4772 4773 // check xawt/libmawt.so 4774 strcpy(libmawtpath, buf); 4775 strcat(libmawtpath, xawtstr); 4776 if (::stat(libmawtpath, &statbuf) == 0) return false; 4777 4778 // check libawt_xawt.so 4779 strcpy(libmawtpath, buf); 4780 strcat(libmawtpath, new_xawtstr); 4781 if (::stat(libmawtpath, &statbuf) == 0) return false; 4782 4783 return true; 4784#endif 4785} 4786 4787// Get the default path to the core file 4788// Returns the length of the string 4789int os::get_core_path(char* buffer, size_t bufferSize) { 4790 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4791 4792 // Truncate if theoretical string was longer than bufferSize 4793 n = MIN2(n, (int)bufferSize); 4794 4795 return n; 4796} 4797 4798#ifndef PRODUCT 4799void TestReserveMemorySpecial_test() { 4800 // No tests available for this platform 4801} 4802#endif 4803