os_bsd.cpp revision 6350:d11386591874
1/* 2 * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25// no precompiled headers 26#include "classfile/classLoader.hpp" 27#include "classfile/systemDictionary.hpp" 28#include "classfile/vmSymbols.hpp" 29#include "code/icBuffer.hpp" 30#include "code/vtableStubs.hpp" 31#include "compiler/compileBroker.hpp" 32#include "compiler/disassembler.hpp" 33#include "interpreter/interpreter.hpp" 34#include "jvm_bsd.h" 35#include "memory/allocation.inline.hpp" 36#include "memory/filemap.hpp" 37#include "mutex_bsd.inline.hpp" 38#include "oops/oop.inline.hpp" 39#include "os_share_bsd.hpp" 40#include "prims/jniFastGetField.hpp" 41#include "prims/jvm.h" 42#include "prims/jvm_misc.hpp" 43#include "runtime/arguments.hpp" 44#include "runtime/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#ifdef __APPLE__ 131mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 132volatile uint64_t os::Bsd::_max_abstime = 0; 133#else 134int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 135#endif 136pthread_t os::Bsd::_main_thread; 137int os::Bsd::_page_size = -1; 138 139static jlong initial_time_count=0; 140 141static int clock_tics_per_sec = 100; 142 143// For diagnostics to print a message once. see run_periodic_checks 144static sigset_t check_signal_done; 145static bool check_signals = true; 146 147static pid_t _initial_pid = 0; 148 149/* Signal number used to suspend/resume a thread */ 150 151/* do not use any signal number less than SIGSEGV, see 4355769 */ 152static int SR_signum = SIGUSR2; 153sigset_t SR_sigset; 154 155 156//////////////////////////////////////////////////////////////////////////////// 157// utility functions 158 159static int SR_initialize(); 160static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 161 162julong os::available_memory() { 163 return Bsd::available_memory(); 164} 165 166// available here means free 167julong os::Bsd::available_memory() { 168 uint64_t available = physical_memory() >> 2; 169#ifdef __APPLE__ 170 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 171 vm_statistics64_data_t vmstat; 172 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 173 (host_info64_t)&vmstat, &count); 174 assert(kerr == KERN_SUCCESS, 175 "host_statistics64 failed - check mach_host_self() and count"); 176 if (kerr == KERN_SUCCESS) { 177 available = vmstat.free_count * os::vm_page_size(); 178 } 179#endif 180 return available; 181} 182 183julong os::physical_memory() { 184 return Bsd::physical_memory(); 185} 186 187//////////////////////////////////////////////////////////////////////////////// 188// environment support 189 190bool os::getenv(const char* name, char* buf, int len) { 191 const char* val = ::getenv(name); 192 if (val != NULL && strlen(val) < (size_t)len) { 193 strcpy(buf, val); 194 return true; 195 } 196 if (len > 0) buf[0] = 0; // return a null string 197 return false; 198} 199 200 201// Return true if user is running as root. 202 203bool os::have_special_privileges() { 204 static bool init = false; 205 static bool privileges = false; 206 if (!init) { 207 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 208 init = true; 209 } 210 return privileges; 211} 212 213 214 215// Cpu architecture string 216#if defined(ZERO) 217static char cpu_arch[] = ZERO_LIBARCH; 218#elif defined(IA64) 219static char cpu_arch[] = "ia64"; 220#elif defined(IA32) 221static char cpu_arch[] = "i386"; 222#elif defined(AMD64) 223static char cpu_arch[] = "amd64"; 224#elif defined(ARM) 225static char cpu_arch[] = "arm"; 226#elif defined(PPC32) 227static char cpu_arch[] = "ppc"; 228#elif defined(SPARC) 229# ifdef _LP64 230static char cpu_arch[] = "sparcv9"; 231# else 232static char cpu_arch[] = "sparc"; 233# endif 234#else 235#error Add appropriate cpu_arch setting 236#endif 237 238// Compiler variant 239#ifdef COMPILER2 240#define COMPILER_VARIANT "server" 241#else 242#define COMPILER_VARIANT "client" 243#endif 244 245 246void os::Bsd::initialize_system_info() { 247 int mib[2]; 248 size_t len; 249 int cpu_val; 250 julong mem_val; 251 252 /* get processors count via hw.ncpus sysctl */ 253 mib[0] = CTL_HW; 254 mib[1] = HW_NCPU; 255 len = sizeof(cpu_val); 256 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 257 assert(len == sizeof(cpu_val), "unexpected data size"); 258 set_processor_count(cpu_val); 259 } 260 else { 261 set_processor_count(1); // fallback 262 } 263 264 /* get physical memory via hw.memsize sysctl (hw.memsize is used 265 * since it returns a 64 bit value) 266 */ 267 mib[0] = CTL_HW; 268 269#if defined (HW_MEMSIZE) // Apple 270 mib[1] = HW_MEMSIZE; 271#elif defined(HW_PHYSMEM) // Most of BSD 272 mib[1] = HW_PHYSMEM; 273#elif defined(HW_REALMEM) // Old FreeBSD 274 mib[1] = HW_REALMEM; 275#else 276 #error No ways to get physmem 277#endif 278 279 len = sizeof(mem_val); 280 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 281 assert(len == sizeof(mem_val), "unexpected data size"); 282 _physical_memory = mem_val; 283 } else { 284 _physical_memory = 256*1024*1024; // fallback (XXXBSD?) 285 } 286 287#ifdef __OpenBSD__ 288 { 289 // limit _physical_memory memory view on OpenBSD since 290 // datasize rlimit restricts us anyway. 291 struct rlimit limits; 292 getrlimit(RLIMIT_DATA, &limits); 293 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 294 } 295#endif 296} 297 298#ifdef __APPLE__ 299static const char *get_home() { 300 const char *home_dir = ::getenv("HOME"); 301 if ((home_dir == NULL) || (*home_dir == '\0')) { 302 struct passwd *passwd_info = getpwuid(geteuid()); 303 if (passwd_info != NULL) { 304 home_dir = passwd_info->pw_dir; 305 } 306 } 307 308 return home_dir; 309} 310#endif 311 312void os::init_system_properties_values() { 313 // The next steps are taken in the product version: 314 // 315 // Obtain the JAVA_HOME value from the location of libjvm.so. 316 // This library should be located at: 317 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 318 // 319 // If "/jre/lib/" appears at the right place in the path, then we 320 // assume libjvm.so is installed in a JDK and we use this path. 321 // 322 // Otherwise exit with message: "Could not create the Java virtual machine." 323 // 324 // The following extra steps are taken in the debugging version: 325 // 326 // If "/jre/lib/" does NOT appear at the right place in the path 327 // instead of exit check for $JAVA_HOME environment variable. 328 // 329 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 330 // then we append a fake suffix "hotspot/libjvm.so" to this path so 331 // it looks like libjvm.so is installed there 332 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 333 // 334 // Otherwise exit. 335 // 336 // Important note: if the location of libjvm.so changes this 337 // code needs to be changed accordingly. 338 339// See ld(1): 340// The linker uses the following search paths to locate required 341// shared libraries: 342// 1: ... 343// ... 344// 7: The default directories, normally /lib and /usr/lib. 345#ifndef DEFAULT_LIBPATH 346#define DEFAULT_LIBPATH "/lib:/usr/lib" 347#endif 348 349// Base path of extensions installed on the system. 350#define SYS_EXT_DIR "/usr/java/packages" 351#define EXTENSIONS_DIR "/lib/ext" 352#define ENDORSED_DIR "/lib/endorsed" 353 354#ifndef __APPLE__ 355 356 // Buffer that fits several sprintfs. 357 // Note that the space for the colon and the trailing null are provided 358 // by the nulls included by the sizeof operator. 359 const size_t bufsize = 360 MAX3((size_t)MAXPATHLEN, // For dll_dir & friends. 361 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir 362 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir 363 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 364 365 // sysclasspath, java_home, dll_dir 366 { 367 char *pslash; 368 os::jvm_path(buf, bufsize); 369 370 // Found the full path to libjvm.so. 371 // Now cut the path to <java_home>/jre if we can. 372 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 373 pslash = strrchr(buf, '/'); 374 if (pslash != NULL) { 375 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 376 } 377 Arguments::set_dll_dir(buf); 378 379 if (pslash != NULL) { 380 pslash = strrchr(buf, '/'); 381 if (pslash != NULL) { 382 *pslash = '\0'; // Get rid of /<arch>. 383 pslash = strrchr(buf, '/'); 384 if (pslash != NULL) { 385 *pslash = '\0'; // Get rid of /lib. 386 } 387 } 388 } 389 Arguments::set_java_home(buf); 390 set_boot_path('/', ':'); 391 } 392 393 // Where to look for native libraries. 394 // 395 // Note: Due to a legacy implementation, most of the library path 396 // is set in the launcher. This was to accomodate linking restrictions 397 // on legacy Bsd implementations (which are no longer supported). 398 // Eventually, all the library path setting will be done here. 399 // 400 // However, to prevent the proliferation of improperly built native 401 // libraries, the new path component /usr/java/packages is added here. 402 // Eventually, all the library path setting will be done here. 403 { 404 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 405 // should always exist (until the legacy problem cited above is 406 // addressed). 407 const char *v = ::getenv("LD_LIBRARY_PATH"); 408 const char *v_colon = ":"; 409 if (v == NULL) { v = ""; v_colon = ""; } 410 // That's +1 for the colon and +1 for the trailing '\0'. 411 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 412 strlen(v) + 1 + 413 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 414 mtInternal); 415 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 416 Arguments::set_library_path(ld_library_path); 417 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); 418 } 419 420 // Extensions directories. 421 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 422 Arguments::set_ext_dirs(buf); 423 424 // Endorsed standards default directory. 425 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 426 Arguments::set_endorsed_dirs(buf); 427 428 FREE_C_HEAP_ARRAY(char, buf, mtInternal); 429 430#else // __APPLE__ 431 432#define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 433#define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 434 435 const char *user_home_dir = get_home(); 436 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 437 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 438 sizeof(SYS_EXTENSIONS_DIRS); 439 440 // Buffer that fits several sprintfs. 441 // Note that the space for the colon and the trailing null are provided 442 // by the nulls included by the sizeof operator. 443 const size_t bufsize = 444 MAX3((size_t)MAXPATHLEN, // for dll_dir & friends. 445 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir 446 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir 447 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 448 449 // sysclasspath, java_home, dll_dir 450 { 451 char *pslash; 452 os::jvm_path(buf, bufsize); 453 454 // Found the full path to libjvm.so. 455 // Now cut the path to <java_home>/jre if we can. 456 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 457 pslash = strrchr(buf, '/'); 458 if (pslash != NULL) { 459 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 460 } 461 Arguments::set_dll_dir(buf); 462 463 if (pslash != NULL) { 464 pslash = strrchr(buf, '/'); 465 if (pslash != NULL) { 466 *pslash = '\0'; // Get rid of /lib. 467 } 468 } 469 Arguments::set_java_home(buf); 470 set_boot_path('/', ':'); 471 } 472 473 // Where to look for native libraries. 474 // 475 // Note: Due to a legacy implementation, most of the library path 476 // is set in the launcher. This was to accomodate linking restrictions 477 // on legacy Bsd implementations (which are no longer supported). 478 // Eventually, all the library path setting will be done here. 479 // 480 // However, to prevent the proliferation of improperly built native 481 // libraries, the new path component /usr/java/packages is added here. 482 // Eventually, all the library path setting will be done here. 483 { 484 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 485 // should always exist (until the legacy problem cited above is 486 // addressed). 487 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 488 // can specify a directory inside an app wrapper 489 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 490 const char *l_colon = ":"; 491 if (l == NULL) { l = ""; l_colon = ""; } 492 493 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 494 const char *v_colon = ":"; 495 if (v == NULL) { v = ""; v_colon = ""; } 496 497 // Apple's Java6 has "." at the beginning of java.library.path. 498 // OpenJDK on Windows has "." at the end of java.library.path. 499 // OpenJDK on Linux and Solaris don't have "." in java.library.path 500 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 501 // "." is appended to the end of java.library.path. Yes, this 502 // could cause a change in behavior, but Apple's Java6 behavior 503 // can be achieved by putting "." at the beginning of the 504 // JAVA_LIBRARY_PATH environment variable. 505 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 506 strlen(v) + 1 + strlen(l) + 1 + 507 system_ext_size + 3, 508 mtInternal); 509 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 510 v, v_colon, l, l_colon, user_home_dir); 511 Arguments::set_library_path(ld_library_path); 512 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); 513 } 514 515 // Extensions directories. 516 // 517 // Note that the space for the colon and the trailing null are provided 518 // by the nulls included by the sizeof operator (so actually one byte more 519 // than necessary is allocated). 520 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 521 user_home_dir, Arguments::get_java_home()); 522 Arguments::set_ext_dirs(buf); 523 524 // Endorsed standards default directory. 525 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 526 Arguments::set_endorsed_dirs(buf); 527 528 FREE_C_HEAP_ARRAY(char, buf, mtInternal); 529 530#undef SYS_EXTENSIONS_DIR 531#undef SYS_EXTENSIONS_DIRS 532 533#endif // __APPLE__ 534 535#undef SYS_EXT_DIR 536#undef EXTENSIONS_DIR 537#undef ENDORSED_DIR 538} 539 540//////////////////////////////////////////////////////////////////////////////// 541// breakpoint support 542 543void os::breakpoint() { 544 BREAKPOINT; 545} 546 547extern "C" void breakpoint() { 548 // use debugger to set breakpoint here 549} 550 551//////////////////////////////////////////////////////////////////////////////// 552// signal support 553 554debug_only(static bool signal_sets_initialized = false); 555static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 556 557bool os::Bsd::is_sig_ignored(int sig) { 558 struct sigaction oact; 559 sigaction(sig, (struct sigaction*)NULL, &oact); 560 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 561 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 562 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 563 return true; 564 else 565 return false; 566} 567 568void os::Bsd::signal_sets_init() { 569 // Should also have an assertion stating we are still single-threaded. 570 assert(!signal_sets_initialized, "Already initialized"); 571 // Fill in signals that are necessarily unblocked for all threads in 572 // the VM. Currently, we unblock the following signals: 573 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 574 // by -Xrs (=ReduceSignalUsage)); 575 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 576 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 577 // the dispositions or masks wrt these signals. 578 // Programs embedding the VM that want to use the above signals for their 579 // own purposes must, at this time, use the "-Xrs" option to prevent 580 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 581 // (See bug 4345157, and other related bugs). 582 // In reality, though, unblocking these signals is really a nop, since 583 // these signals are not blocked by default. 584 sigemptyset(&unblocked_sigs); 585 sigemptyset(&allowdebug_blocked_sigs); 586 sigaddset(&unblocked_sigs, SIGILL); 587 sigaddset(&unblocked_sigs, SIGSEGV); 588 sigaddset(&unblocked_sigs, SIGBUS); 589 sigaddset(&unblocked_sigs, SIGFPE); 590 sigaddset(&unblocked_sigs, SR_signum); 591 592 if (!ReduceSignalUsage) { 593 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 594 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 595 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 596 } 597 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 598 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 599 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 600 } 601 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 602 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 603 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 604 } 605 } 606 // Fill in signals that are blocked by all but the VM thread. 607 sigemptyset(&vm_sigs); 608 if (!ReduceSignalUsage) 609 sigaddset(&vm_sigs, BREAK_SIGNAL); 610 debug_only(signal_sets_initialized = true); 611 612} 613 614// These are signals that are unblocked while a thread is running Java. 615// (For some reason, they get blocked by default.) 616sigset_t* os::Bsd::unblocked_signals() { 617 assert(signal_sets_initialized, "Not initialized"); 618 return &unblocked_sigs; 619} 620 621// These are the signals that are blocked while a (non-VM) thread is 622// running Java. Only the VM thread handles these signals. 623sigset_t* os::Bsd::vm_signals() { 624 assert(signal_sets_initialized, "Not initialized"); 625 return &vm_sigs; 626} 627 628// These are signals that are blocked during cond_wait to allow debugger in 629sigset_t* os::Bsd::allowdebug_blocked_signals() { 630 assert(signal_sets_initialized, "Not initialized"); 631 return &allowdebug_blocked_sigs; 632} 633 634void os::Bsd::hotspot_sigmask(Thread* thread) { 635 636 //Save caller's signal mask before setting VM signal mask 637 sigset_t caller_sigmask; 638 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 639 640 OSThread* osthread = thread->osthread(); 641 osthread->set_caller_sigmask(caller_sigmask); 642 643 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 644 645 if (!ReduceSignalUsage) { 646 if (thread->is_VM_thread()) { 647 // Only the VM thread handles BREAK_SIGNAL ... 648 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 649 } else { 650 // ... all other threads block BREAK_SIGNAL 651 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 652 } 653 } 654} 655 656 657////////////////////////////////////////////////////////////////////////////// 658// create new thread 659 660// check if it's safe to start a new thread 661static bool _thread_safety_check(Thread* thread) { 662 return true; 663} 664 665#ifdef __APPLE__ 666// library handle for calling objc_registerThreadWithCollector() 667// without static linking to the libobjc library 668#define OBJC_LIB "/usr/lib/libobjc.dylib" 669#define OBJC_GCREGISTER "objc_registerThreadWithCollector" 670typedef void (*objc_registerThreadWithCollector_t)(); 671extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 672objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 673#endif 674 675#ifdef __APPLE__ 676static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 677 // Additional thread_id used to correlate threads in SA 678 thread_identifier_info_data_t m_ident_info; 679 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 680 681 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 682 (thread_info_t) &m_ident_info, &count); 683 684 return m_ident_info.thread_id; 685} 686#endif 687 688// Thread start routine for all newly created threads 689static void *java_start(Thread *thread) { 690 // Try to randomize the cache line index of hot stack frames. 691 // This helps when threads of the same stack traces evict each other's 692 // cache lines. The threads can be either from the same JVM instance, or 693 // from different JVM instances. The benefit is especially true for 694 // processors with hyperthreading technology. 695 static int counter = 0; 696 int pid = os::current_process_id(); 697 alloca(((pid ^ counter++) & 7) * 128); 698 699 ThreadLocalStorage::set_thread(thread); 700 701 OSThread* osthread = thread->osthread(); 702 Monitor* sync = osthread->startThread_lock(); 703 704 // non floating stack BsdThreads needs extra check, see above 705 if (!_thread_safety_check(thread)) { 706 // notify parent thread 707 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 708 osthread->set_state(ZOMBIE); 709 sync->notify_all(); 710 return NULL; 711 } 712 713 osthread->set_thread_id(os::Bsd::gettid()); 714 715#ifdef __APPLE__ 716 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 717 guarantee(unique_thread_id != 0, "unique thread id was not found"); 718 osthread->set_unique_thread_id(unique_thread_id); 719#endif 720 // initialize signal mask for this thread 721 os::Bsd::hotspot_sigmask(thread); 722 723 // initialize floating point control register 724 os::Bsd::init_thread_fpu_state(); 725 726#ifdef __APPLE__ 727 // register thread with objc gc 728 if (objc_registerThreadWithCollectorFunction != NULL) { 729 objc_registerThreadWithCollectorFunction(); 730 } 731#endif 732 733 // handshaking with parent thread 734 { 735 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 736 737 // notify parent thread 738 osthread->set_state(INITIALIZED); 739 sync->notify_all(); 740 741 // wait until os::start_thread() 742 while (osthread->get_state() == INITIALIZED) { 743 sync->wait(Mutex::_no_safepoint_check_flag); 744 } 745 } 746 747 // call one more level start routine 748 thread->run(); 749 750 return 0; 751} 752 753bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 754 assert(thread->osthread() == NULL, "caller responsible"); 755 756 // Allocate the OSThread object 757 OSThread* osthread = new OSThread(NULL, NULL); 758 if (osthread == NULL) { 759 return false; 760 } 761 762 // set the correct thread state 763 osthread->set_thread_type(thr_type); 764 765 // Initial state is ALLOCATED but not INITIALIZED 766 osthread->set_state(ALLOCATED); 767 768 thread->set_osthread(osthread); 769 770 // init thread attributes 771 pthread_attr_t attr; 772 pthread_attr_init(&attr); 773 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 774 775 // stack size 776 if (os::Bsd::supports_variable_stack_size()) { 777 // calculate stack size if it's not specified by caller 778 if (stack_size == 0) { 779 stack_size = os::Bsd::default_stack_size(thr_type); 780 781 switch (thr_type) { 782 case os::java_thread: 783 // Java threads use ThreadStackSize which default value can be 784 // changed with the flag -Xss 785 assert (JavaThread::stack_size_at_create() > 0, "this should be set"); 786 stack_size = JavaThread::stack_size_at_create(); 787 break; 788 case os::compiler_thread: 789 if (CompilerThreadStackSize > 0) { 790 stack_size = (size_t)(CompilerThreadStackSize * K); 791 break; 792 } // else fall through: 793 // use VMThreadStackSize if CompilerThreadStackSize is not defined 794 case os::vm_thread: 795 case os::pgc_thread: 796 case os::cgc_thread: 797 case os::watcher_thread: 798 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 799 break; 800 } 801 } 802 803 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 804 pthread_attr_setstacksize(&attr, stack_size); 805 } else { 806 // let pthread_create() pick the default value. 807 } 808 809 ThreadState state; 810 811 { 812 pthread_t tid; 813 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 814 815 pthread_attr_destroy(&attr); 816 817 if (ret != 0) { 818 if (PrintMiscellaneous && (Verbose || WizardMode)) { 819 perror("pthread_create()"); 820 } 821 // Need to clean up stuff we've allocated so far 822 thread->set_osthread(NULL); 823 delete osthread; 824 return false; 825 } 826 827 // Store pthread info into the OSThread 828 osthread->set_pthread_id(tid); 829 830 // Wait until child thread is either initialized or aborted 831 { 832 Monitor* sync_with_child = osthread->startThread_lock(); 833 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 834 while ((state = osthread->get_state()) == ALLOCATED) { 835 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 836 } 837 } 838 839 } 840 841 // Aborted due to thread limit being reached 842 if (state == ZOMBIE) { 843 thread->set_osthread(NULL); 844 delete osthread; 845 return false; 846 } 847 848 // The thread is returned suspended (in state INITIALIZED), 849 // and is started higher up in the call chain 850 assert(state == INITIALIZED, "race condition"); 851 return true; 852} 853 854///////////////////////////////////////////////////////////////////////////// 855// attach existing thread 856 857// bootstrap the main thread 858bool os::create_main_thread(JavaThread* thread) { 859 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 860 return create_attached_thread(thread); 861} 862 863bool os::create_attached_thread(JavaThread* thread) { 864#ifdef ASSERT 865 thread->verify_not_published(); 866#endif 867 868 // Allocate the OSThread object 869 OSThread* osthread = new OSThread(NULL, NULL); 870 871 if (osthread == NULL) { 872 return false; 873 } 874 875 osthread->set_thread_id(os::Bsd::gettid()); 876 877 // Store pthread info into the OSThread 878#ifdef __APPLE__ 879 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 880 guarantee(unique_thread_id != 0, "just checking"); 881 osthread->set_unique_thread_id(unique_thread_id); 882#endif 883 osthread->set_pthread_id(::pthread_self()); 884 885 // initialize floating point control register 886 os::Bsd::init_thread_fpu_state(); 887 888 // Initial thread state is RUNNABLE 889 osthread->set_state(RUNNABLE); 890 891 thread->set_osthread(osthread); 892 893 // initialize signal mask for this thread 894 // and save the caller's signal mask 895 os::Bsd::hotspot_sigmask(thread); 896 897 return true; 898} 899 900void os::pd_start_thread(Thread* thread) { 901 OSThread * osthread = thread->osthread(); 902 assert(osthread->get_state() != INITIALIZED, "just checking"); 903 Monitor* sync_with_child = osthread->startThread_lock(); 904 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 905 sync_with_child->notify(); 906} 907 908// Free Bsd resources related to the OSThread 909void os::free_thread(OSThread* osthread) { 910 assert(osthread != NULL, "osthread not set"); 911 912 if (Thread::current()->osthread() == osthread) { 913 // Restore caller's signal mask 914 sigset_t sigmask = osthread->caller_sigmask(); 915 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 916 } 917 918 delete osthread; 919} 920 921////////////////////////////////////////////////////////////////////////////// 922// thread local storage 923 924// Restore the thread pointer if the destructor is called. This is in case 925// someone from JNI code sets up a destructor with pthread_key_create to run 926// detachCurrentThread on thread death. Unless we restore the thread pointer we 927// will hang or crash. When detachCurrentThread is called the key will be set 928// to null and we will not be called again. If detachCurrentThread is never 929// called we could loop forever depending on the pthread implementation. 930static void restore_thread_pointer(void* p) { 931 Thread* thread = (Thread*) p; 932 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread); 933} 934 935int os::allocate_thread_local_storage() { 936 pthread_key_t key; 937 int rslt = pthread_key_create(&key, restore_thread_pointer); 938 assert(rslt == 0, "cannot allocate thread local storage"); 939 return (int)key; 940} 941 942// Note: This is currently not used by VM, as we don't destroy TLS key 943// on VM exit. 944void os::free_thread_local_storage(int index) { 945 int rslt = pthread_key_delete((pthread_key_t)index); 946 assert(rslt == 0, "invalid index"); 947} 948 949void os::thread_local_storage_at_put(int index, void* value) { 950 int rslt = pthread_setspecific((pthread_key_t)index, value); 951 assert(rslt == 0, "pthread_setspecific failed"); 952} 953 954extern "C" Thread* get_thread() { 955 return ThreadLocalStorage::thread(); 956} 957 958 959//////////////////////////////////////////////////////////////////////////////// 960// time support 961 962// Time since start-up in seconds to a fine granularity. 963// Used by VMSelfDestructTimer and the MemProfiler. 964double os::elapsedTime() { 965 966 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 967} 968 969jlong os::elapsed_counter() { 970 return javaTimeNanos() - initial_time_count; 971} 972 973jlong os::elapsed_frequency() { 974 return NANOSECS_PER_SEC; // nanosecond resolution 975} 976 977bool os::supports_vtime() { return true; } 978bool os::enable_vtime() { return false; } 979bool os::vtime_enabled() { return false; } 980 981double os::elapsedVTime() { 982 // better than nothing, but not much 983 return elapsedTime(); 984} 985 986jlong os::javaTimeMillis() { 987 timeval time; 988 int status = gettimeofday(&time, NULL); 989 assert(status != -1, "bsd error"); 990 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 991} 992 993#ifndef __APPLE__ 994#ifndef CLOCK_MONOTONIC 995#define CLOCK_MONOTONIC (1) 996#endif 997#endif 998 999#ifdef __APPLE__ 1000void os::Bsd::clock_init() { 1001 mach_timebase_info(&_timebase_info); 1002} 1003#else 1004void os::Bsd::clock_init() { 1005 struct timespec res; 1006 struct timespec tp; 1007 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 1008 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 1009 // yes, monotonic clock is supported 1010 _clock_gettime = ::clock_gettime; 1011 } 1012} 1013#endif 1014 1015 1016 1017#ifdef __APPLE__ 1018 1019jlong os::javaTimeNanos() { 1020 const uint64_t tm = mach_absolute_time(); 1021 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 1022 const uint64_t prev = Bsd::_max_abstime; 1023 if (now <= prev) { 1024 return prev; // same or retrograde time; 1025 } 1026 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 1027 assert(obsv >= prev, "invariant"); // Monotonicity 1028 // If the CAS succeeded then we're done and return "now". 1029 // If the CAS failed and the observed value "obsv" is >= now then 1030 // we should return "obsv". If the CAS failed and now > obsv > prv then 1031 // some other thread raced this thread and installed a new value, in which case 1032 // we could either (a) retry the entire operation, (b) retry trying to install now 1033 // or (c) just return obsv. We use (c). No loop is required although in some cases 1034 // we might discard a higher "now" value in deference to a slightly lower but freshly 1035 // installed obsv value. That's entirely benign -- it admits no new orderings compared 1036 // to (a) or (b) -- and greatly reduces coherence traffic. 1037 // We might also condition (c) on the magnitude of the delta between obsv and now. 1038 // Avoiding excessive CAS operations to hot RW locations is critical. 1039 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 1040 return (prev == obsv) ? now : obsv; 1041} 1042 1043#else // __APPLE__ 1044 1045jlong os::javaTimeNanos() { 1046 if (os::supports_monotonic_clock()) { 1047 struct timespec tp; 1048 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 1049 assert(status == 0, "gettime error"); 1050 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1051 return result; 1052 } else { 1053 timeval time; 1054 int status = gettimeofday(&time, NULL); 1055 assert(status != -1, "bsd error"); 1056 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1057 return 1000 * usecs; 1058 } 1059} 1060 1061#endif // __APPLE__ 1062 1063void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1064 if (os::supports_monotonic_clock()) { 1065 info_ptr->max_value = ALL_64_BITS; 1066 1067 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1068 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1069 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1070 } else { 1071 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1072 info_ptr->max_value = ALL_64_BITS; 1073 1074 // gettimeofday is a real time clock so it skips 1075 info_ptr->may_skip_backward = true; 1076 info_ptr->may_skip_forward = true; 1077 } 1078 1079 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1080} 1081 1082// Return the real, user, and system times in seconds from an 1083// arbitrary fixed point in the past. 1084bool os::getTimesSecs(double* process_real_time, 1085 double* process_user_time, 1086 double* process_system_time) { 1087 struct tms ticks; 1088 clock_t real_ticks = times(&ticks); 1089 1090 if (real_ticks == (clock_t) (-1)) { 1091 return false; 1092 } else { 1093 double ticks_per_second = (double) clock_tics_per_sec; 1094 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1095 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1096 *process_real_time = ((double) real_ticks) / ticks_per_second; 1097 1098 return true; 1099 } 1100} 1101 1102 1103char * os::local_time_string(char *buf, size_t buflen) { 1104 struct tm t; 1105 time_t long_time; 1106 time(&long_time); 1107 localtime_r(&long_time, &t); 1108 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1109 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1110 t.tm_hour, t.tm_min, t.tm_sec); 1111 return buf; 1112} 1113 1114struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1115 return localtime_r(clock, res); 1116} 1117 1118//////////////////////////////////////////////////////////////////////////////// 1119// runtime exit support 1120 1121// Note: os::shutdown() might be called very early during initialization, or 1122// called from signal handler. Before adding something to os::shutdown(), make 1123// sure it is async-safe and can handle partially initialized VM. 1124void os::shutdown() { 1125 1126 // allow PerfMemory to attempt cleanup of any persistent resources 1127 perfMemory_exit(); 1128 1129 // needs to remove object in file system 1130 AttachListener::abort(); 1131 1132 // flush buffered output, finish log files 1133 ostream_abort(); 1134 1135 // Check for abort hook 1136 abort_hook_t abort_hook = Arguments::abort_hook(); 1137 if (abort_hook != NULL) { 1138 abort_hook(); 1139 } 1140 1141} 1142 1143// Note: os::abort() might be called very early during initialization, or 1144// called from signal handler. Before adding something to os::abort(), make 1145// sure it is async-safe and can handle partially initialized VM. 1146void os::abort(bool dump_core) { 1147 os::shutdown(); 1148 if (dump_core) { 1149#ifndef PRODUCT 1150 fdStream out(defaultStream::output_fd()); 1151 out.print_raw("Current thread is "); 1152 char buf[16]; 1153 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1154 out.print_raw_cr(buf); 1155 out.print_raw_cr("Dumping core ..."); 1156#endif 1157 ::abort(); // dump core 1158 } 1159 1160 ::exit(1); 1161} 1162 1163// Die immediately, no exit hook, no abort hook, no cleanup. 1164void os::die() { 1165 // _exit() on BsdThreads only kills current thread 1166 ::abort(); 1167} 1168 1169// unused on bsd for now. 1170void os::set_error_file(const char *logfile) {} 1171 1172 1173// This method is a copy of JDK's sysGetLastErrorString 1174// from src/solaris/hpi/src/system_md.c 1175 1176size_t os::lasterror(char *buf, size_t len) { 1177 1178 if (errno == 0) return 0; 1179 1180 const char *s = ::strerror(errno); 1181 size_t n = ::strlen(s); 1182 if (n >= len) { 1183 n = len - 1; 1184 } 1185 ::strncpy(buf, s, n); 1186 buf[n] = '\0'; 1187 return n; 1188} 1189 1190// Information of current thread in variety of formats 1191pid_t os::Bsd::gettid() { 1192 int retval = -1; 1193 1194#ifdef __APPLE__ //XNU kernel 1195 // despite the fact mach port is actually not a thread id use it 1196 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1197 retval = ::pthread_mach_thread_np(::pthread_self()); 1198 guarantee(retval != 0, "just checking"); 1199 return retval; 1200 1201#elif __FreeBSD__ 1202 retval = syscall(SYS_thr_self); 1203#elif __OpenBSD__ 1204 retval = syscall(SYS_getthrid); 1205#elif __NetBSD__ 1206 retval = (pid_t) syscall(SYS__lwp_self); 1207#endif 1208 1209 if (retval == -1) { 1210 return getpid(); 1211 } 1212} 1213 1214intx os::current_thread_id() { 1215#ifdef __APPLE__ 1216 return (intx)::pthread_mach_thread_np(::pthread_self()); 1217#else 1218 return (intx)::pthread_self(); 1219#endif 1220} 1221 1222int os::current_process_id() { 1223 1224 // Under the old bsd thread library, bsd gives each thread 1225 // its own process id. Because of this each thread will return 1226 // a different pid if this method were to return the result 1227 // of getpid(2). Bsd provides no api that returns the pid 1228 // of the launcher thread for the vm. This implementation 1229 // returns a unique pid, the pid of the launcher thread 1230 // that starts the vm 'process'. 1231 1232 // Under the NPTL, getpid() returns the same pid as the 1233 // launcher thread rather than a unique pid per thread. 1234 // Use gettid() if you want the old pre NPTL behaviour. 1235 1236 // if you are looking for the result of a call to getpid() that 1237 // returns a unique pid for the calling thread, then look at the 1238 // OSThread::thread_id() method in osThread_bsd.hpp file 1239 1240 return (int)(_initial_pid ? _initial_pid : getpid()); 1241} 1242 1243// DLL functions 1244 1245#define JNI_LIB_PREFIX "lib" 1246#ifdef __APPLE__ 1247#define JNI_LIB_SUFFIX ".dylib" 1248#else 1249#define JNI_LIB_SUFFIX ".so" 1250#endif 1251 1252const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1253 1254// This must be hard coded because it's the system's temporary 1255// directory not the java application's temp directory, ala java.io.tmpdir. 1256#ifdef __APPLE__ 1257// macosx has a secure per-user temporary directory 1258char temp_path_storage[PATH_MAX]; 1259const char* os::get_temp_directory() { 1260 static char *temp_path = NULL; 1261 if (temp_path == NULL) { 1262 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1263 if (pathSize == 0 || pathSize > PATH_MAX) { 1264 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1265 } 1266 temp_path = temp_path_storage; 1267 } 1268 return temp_path; 1269} 1270#else /* __APPLE__ */ 1271const char* os::get_temp_directory() { return "/tmp"; } 1272#endif /* __APPLE__ */ 1273 1274static bool file_exists(const char* filename) { 1275 struct stat statbuf; 1276 if (filename == NULL || strlen(filename) == 0) { 1277 return false; 1278 } 1279 return os::stat(filename, &statbuf) == 0; 1280} 1281 1282bool os::dll_build_name(char* buffer, size_t buflen, 1283 const char* pname, const char* fname) { 1284 bool retval = false; 1285 // Copied from libhpi 1286 const size_t pnamelen = pname ? strlen(pname) : 0; 1287 1288 // Return error on buffer overflow. 1289 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1290 return retval; 1291 } 1292 1293 if (pnamelen == 0) { 1294 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1295 retval = true; 1296 } else if (strchr(pname, *os::path_separator()) != NULL) { 1297 int n; 1298 char** pelements = split_path(pname, &n); 1299 if (pelements == NULL) { 1300 return false; 1301 } 1302 for (int i = 0 ; i < n ; i++) { 1303 // Really shouldn't be NULL, but check can't hurt 1304 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1305 continue; // skip the empty path values 1306 } 1307 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1308 pelements[i], fname); 1309 if (file_exists(buffer)) { 1310 retval = true; 1311 break; 1312 } 1313 } 1314 // release the storage 1315 for (int i = 0 ; i < n ; i++) { 1316 if (pelements[i] != NULL) { 1317 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1318 } 1319 } 1320 if (pelements != NULL) { 1321 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1322 } 1323 } else { 1324 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1325 retval = true; 1326 } 1327 return retval; 1328} 1329 1330// check if addr is inside libjvm.so 1331bool os::address_is_in_vm(address addr) { 1332 static address libjvm_base_addr; 1333 Dl_info dlinfo; 1334 1335 if (libjvm_base_addr == NULL) { 1336 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1337 libjvm_base_addr = (address)dlinfo.dli_fbase; 1338 } 1339 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1340 } 1341 1342 if (dladdr((void *)addr, &dlinfo) != 0) { 1343 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1344 } 1345 1346 return false; 1347} 1348 1349 1350#define MACH_MAXSYMLEN 256 1351 1352bool os::dll_address_to_function_name(address addr, char *buf, 1353 int buflen, int *offset) { 1354 // buf is not optional, but offset is optional 1355 assert(buf != NULL, "sanity check"); 1356 1357 Dl_info dlinfo; 1358 char localbuf[MACH_MAXSYMLEN]; 1359 1360 if (dladdr((void*)addr, &dlinfo) != 0) { 1361 // see if we have a matching symbol 1362 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1363 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1364 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1365 } 1366 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1367 return true; 1368 } 1369 // no matching symbol so try for just file info 1370 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1371 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1372 buf, buflen, offset, dlinfo.dli_fname)) { 1373 return true; 1374 } 1375 } 1376 1377 // Handle non-dynamic manually: 1378 if (dlinfo.dli_fbase != NULL && 1379 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1380 dlinfo.dli_fbase)) { 1381 if (!Decoder::demangle(localbuf, buf, buflen)) { 1382 jio_snprintf(buf, buflen, "%s", localbuf); 1383 } 1384 return true; 1385 } 1386 } 1387 buf[0] = '\0'; 1388 if (offset != NULL) *offset = -1; 1389 return false; 1390} 1391 1392// ported from solaris version 1393bool os::dll_address_to_library_name(address addr, char* buf, 1394 int buflen, int* offset) { 1395 // buf is not optional, but offset is optional 1396 assert(buf != NULL, "sanity check"); 1397 1398 Dl_info dlinfo; 1399 1400 if (dladdr((void*)addr, &dlinfo) != 0) { 1401 if (dlinfo.dli_fname != NULL) { 1402 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1403 } 1404 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1405 *offset = addr - (address)dlinfo.dli_fbase; 1406 } 1407 return true; 1408 } 1409 1410 buf[0] = '\0'; 1411 if (offset) *offset = -1; 1412 return false; 1413} 1414 1415// Loads .dll/.so and 1416// in case of error it checks if .dll/.so was built for the 1417// same architecture as Hotspot is running on 1418 1419#ifdef __APPLE__ 1420void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1421 void * result= ::dlopen(filename, RTLD_LAZY); 1422 if (result != NULL) { 1423 // Successful loading 1424 return result; 1425 } 1426 1427 // Read system error message into ebuf 1428 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1429 ebuf[ebuflen-1]='\0'; 1430 1431 return NULL; 1432} 1433#else 1434void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1435{ 1436 void * result= ::dlopen(filename, RTLD_LAZY); 1437 if (result != NULL) { 1438 // Successful loading 1439 return result; 1440 } 1441 1442 Elf32_Ehdr elf_head; 1443 1444 // Read system error message into ebuf 1445 // It may or may not be overwritten below 1446 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1447 ebuf[ebuflen-1]='\0'; 1448 int diag_msg_max_length=ebuflen-strlen(ebuf); 1449 char* diag_msg_buf=ebuf+strlen(ebuf); 1450 1451 if (diag_msg_max_length==0) { 1452 // No more space in ebuf for additional diagnostics message 1453 return NULL; 1454 } 1455 1456 1457 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1458 1459 if (file_descriptor < 0) { 1460 // Can't open library, report dlerror() message 1461 return NULL; 1462 } 1463 1464 bool failed_to_read_elf_head= 1465 (sizeof(elf_head)!= 1466 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 1467 1468 ::close(file_descriptor); 1469 if (failed_to_read_elf_head) { 1470 // file i/o error - report dlerror() msg 1471 return NULL; 1472 } 1473 1474 typedef struct { 1475 Elf32_Half code; // Actual value as defined in elf.h 1476 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1477 char elf_class; // 32 or 64 bit 1478 char endianess; // MSB or LSB 1479 char* name; // String representation 1480 } arch_t; 1481 1482 #ifndef EM_486 1483 #define EM_486 6 /* Intel 80486 */ 1484 #endif 1485 1486 #ifndef EM_MIPS_RS3_LE 1487 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1488 #endif 1489 1490 #ifndef EM_PPC64 1491 #define EM_PPC64 21 /* PowerPC64 */ 1492 #endif 1493 1494 #ifndef EM_S390 1495 #define EM_S390 22 /* IBM System/390 */ 1496 #endif 1497 1498 #ifndef EM_IA_64 1499 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1500 #endif 1501 1502 #ifndef EM_X86_64 1503 #define EM_X86_64 62 /* AMD x86-64 */ 1504 #endif 1505 1506 static const arch_t arch_array[]={ 1507 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1508 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1509 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1510 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1511 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1512 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1513 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1514 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1515 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1516 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1517 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1518 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1519 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1520 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1521 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1522 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1523 }; 1524 1525 #if (defined IA32) 1526 static Elf32_Half running_arch_code=EM_386; 1527 #elif (defined AMD64) 1528 static Elf32_Half running_arch_code=EM_X86_64; 1529 #elif (defined IA64) 1530 static Elf32_Half running_arch_code=EM_IA_64; 1531 #elif (defined __sparc) && (defined _LP64) 1532 static Elf32_Half running_arch_code=EM_SPARCV9; 1533 #elif (defined __sparc) && (!defined _LP64) 1534 static Elf32_Half running_arch_code=EM_SPARC; 1535 #elif (defined __powerpc64__) 1536 static Elf32_Half running_arch_code=EM_PPC64; 1537 #elif (defined __powerpc__) 1538 static Elf32_Half running_arch_code=EM_PPC; 1539 #elif (defined ARM) 1540 static Elf32_Half running_arch_code=EM_ARM; 1541 #elif (defined S390) 1542 static Elf32_Half running_arch_code=EM_S390; 1543 #elif (defined ALPHA) 1544 static Elf32_Half running_arch_code=EM_ALPHA; 1545 #elif (defined MIPSEL) 1546 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1547 #elif (defined PARISC) 1548 static Elf32_Half running_arch_code=EM_PARISC; 1549 #elif (defined MIPS) 1550 static Elf32_Half running_arch_code=EM_MIPS; 1551 #elif (defined M68K) 1552 static Elf32_Half running_arch_code=EM_68K; 1553 #else 1554 #error Method os::dll_load requires that one of following is defined:\ 1555 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1556 #endif 1557 1558 // Identify compatability class for VM's architecture and library's architecture 1559 // Obtain string descriptions for architectures 1560 1561 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1562 int running_arch_index=-1; 1563 1564 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 1565 if (running_arch_code == arch_array[i].code) { 1566 running_arch_index = i; 1567 } 1568 if (lib_arch.code == arch_array[i].code) { 1569 lib_arch.compat_class = arch_array[i].compat_class; 1570 lib_arch.name = arch_array[i].name; 1571 } 1572 } 1573 1574 assert(running_arch_index != -1, 1575 "Didn't find running architecture code (running_arch_code) in arch_array"); 1576 if (running_arch_index == -1) { 1577 // Even though running architecture detection failed 1578 // we may still continue with reporting dlerror() message 1579 return NULL; 1580 } 1581 1582 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1583 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1584 return NULL; 1585 } 1586 1587#ifndef S390 1588 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1589 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1590 return NULL; 1591 } 1592#endif // !S390 1593 1594 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1595 if ( lib_arch.name!=NULL ) { 1596 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1597 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1598 lib_arch.name, arch_array[running_arch_index].name); 1599 } else { 1600 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1601 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1602 lib_arch.code, 1603 arch_array[running_arch_index].name); 1604 } 1605 } 1606 1607 return NULL; 1608} 1609#endif /* !__APPLE__ */ 1610 1611void* os::get_default_process_handle() { 1612#ifdef __APPLE__ 1613 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1614 // to avoid finding unexpected symbols on second (or later) 1615 // loads of a library. 1616 return (void*)::dlopen(NULL, RTLD_FIRST); 1617#else 1618 return (void*)::dlopen(NULL, RTLD_LAZY); 1619#endif 1620} 1621 1622// XXX: Do we need a lock around this as per Linux? 1623void* os::dll_lookup(void* handle, const char* name) { 1624 return dlsym(handle, name); 1625} 1626 1627 1628static bool _print_ascii_file(const char* filename, outputStream* st) { 1629 int fd = ::open(filename, O_RDONLY); 1630 if (fd == -1) { 1631 return false; 1632 } 1633 1634 char buf[32]; 1635 int bytes; 1636 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1637 st->print_raw(buf, bytes); 1638 } 1639 1640 ::close(fd); 1641 1642 return true; 1643} 1644 1645void os::print_dll_info(outputStream *st) { 1646 st->print_cr("Dynamic libraries:"); 1647#ifdef RTLD_DI_LINKMAP 1648 Dl_info dli; 1649 void *handle; 1650 Link_map *map; 1651 Link_map *p; 1652 1653 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1654 dli.dli_fname == NULL) { 1655 st->print_cr("Error: Cannot print dynamic libraries."); 1656 return; 1657 } 1658 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1659 if (handle == NULL) { 1660 st->print_cr("Error: Cannot print dynamic libraries."); 1661 return; 1662 } 1663 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1664 if (map == NULL) { 1665 st->print_cr("Error: Cannot print dynamic libraries."); 1666 return; 1667 } 1668 1669 while (map->l_prev != NULL) 1670 map = map->l_prev; 1671 1672 while (map != NULL) { 1673 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1674 map = map->l_next; 1675 } 1676 1677 dlclose(handle); 1678#elif defined(__APPLE__) 1679 uint32_t count; 1680 uint32_t i; 1681 1682 count = _dyld_image_count(); 1683 for (i = 1; i < count; i++) { 1684 const char *name = _dyld_get_image_name(i); 1685 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 1686 st->print_cr(PTR_FORMAT " \t%s", slide, name); 1687 } 1688#else 1689 st->print_cr("Error: Cannot print dynamic libraries."); 1690#endif 1691} 1692 1693void os::print_os_info_brief(outputStream* st) { 1694 st->print("Bsd"); 1695 1696 os::Posix::print_uname_info(st); 1697} 1698 1699void os::print_os_info(outputStream* st) { 1700 st->print("OS:"); 1701 st->print("Bsd"); 1702 1703 os::Posix::print_uname_info(st); 1704 1705 os::Posix::print_rlimit_info(st); 1706 1707 os::Posix::print_load_average(st); 1708} 1709 1710void os::pd_print_cpu_info(outputStream* st) { 1711 // Nothing to do for now. 1712} 1713 1714void os::print_memory_info(outputStream* st) { 1715 1716 st->print("Memory:"); 1717 st->print(" %dk page", os::vm_page_size()>>10); 1718 1719 st->print(", physical " UINT64_FORMAT "k", 1720 os::physical_memory() >> 10); 1721 st->print("(" UINT64_FORMAT "k free)", 1722 os::available_memory() >> 10); 1723 st->cr(); 1724 1725 // meminfo 1726 st->print("\n/proc/meminfo:\n"); 1727 _print_ascii_file("/proc/meminfo", st); 1728 st->cr(); 1729} 1730 1731void os::print_siginfo(outputStream* st, void* siginfo) { 1732 const siginfo_t* si = (const siginfo_t*)siginfo; 1733 1734 os::Posix::print_siginfo_brief(st, si); 1735 1736 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1737 UseSharedSpaces) { 1738 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1739 if (mapinfo->is_in_shared_space(si->si_addr)) { 1740 st->print("\n\nError accessing class data sharing archive." \ 1741 " Mapped file inaccessible during execution, " \ 1742 " possible disk/network problem."); 1743 } 1744 } 1745 st->cr(); 1746} 1747 1748 1749static void print_signal_handler(outputStream* st, int sig, 1750 char* buf, size_t buflen); 1751 1752void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1753 st->print_cr("Signal Handlers:"); 1754 print_signal_handler(st, SIGSEGV, buf, buflen); 1755 print_signal_handler(st, SIGBUS , buf, buflen); 1756 print_signal_handler(st, SIGFPE , buf, buflen); 1757 print_signal_handler(st, SIGPIPE, buf, buflen); 1758 print_signal_handler(st, SIGXFSZ, buf, buflen); 1759 print_signal_handler(st, SIGILL , buf, buflen); 1760 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1761 print_signal_handler(st, SR_signum, buf, buflen); 1762 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1763 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1764 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1765 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1766} 1767 1768static char saved_jvm_path[MAXPATHLEN] = {0}; 1769 1770// Find the full path to the current module, libjvm 1771void os::jvm_path(char *buf, jint buflen) { 1772 // Error checking. 1773 if (buflen < MAXPATHLEN) { 1774 assert(false, "must use a large-enough buffer"); 1775 buf[0] = '\0'; 1776 return; 1777 } 1778 // Lazy resolve the path to current module. 1779 if (saved_jvm_path[0] != 0) { 1780 strcpy(buf, saved_jvm_path); 1781 return; 1782 } 1783 1784 char dli_fname[MAXPATHLEN]; 1785 bool ret = dll_address_to_library_name( 1786 CAST_FROM_FN_PTR(address, os::jvm_path), 1787 dli_fname, sizeof(dli_fname), NULL); 1788 assert(ret, "cannot locate libjvm"); 1789 char *rp = NULL; 1790 if (ret && dli_fname[0] != '\0') { 1791 rp = realpath(dli_fname, buf); 1792 } 1793 if (rp == NULL) 1794 return; 1795 1796 if (Arguments::sun_java_launcher_is_altjvm()) { 1797 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1798 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1799 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1800 // appears at the right place in the string, then assume we are 1801 // installed in a JDK and we're done. Otherwise, check for a 1802 // JAVA_HOME environment variable and construct a path to the JVM 1803 // being overridden. 1804 1805 const char *p = buf + strlen(buf) - 1; 1806 for (int count = 0; p > buf && count < 5; ++count) { 1807 for (--p; p > buf && *p != '/'; --p) 1808 /* empty */ ; 1809 } 1810 1811 if (strncmp(p, "/jre/lib/", 9) != 0) { 1812 // Look for JAVA_HOME in the environment. 1813 char* java_home_var = ::getenv("JAVA_HOME"); 1814 if (java_home_var != NULL && java_home_var[0] != 0) { 1815 char* jrelib_p; 1816 int len; 1817 1818 // Check the current module name "libjvm" 1819 p = strrchr(buf, '/'); 1820 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1821 1822 rp = realpath(java_home_var, buf); 1823 if (rp == NULL) 1824 return; 1825 1826 // determine if this is a legacy image or modules image 1827 // modules image doesn't have "jre" subdirectory 1828 len = strlen(buf); 1829 jrelib_p = buf + len; 1830 1831 // Add the appropriate library subdir 1832 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1833 if (0 != access(buf, F_OK)) { 1834 snprintf(jrelib_p, buflen-len, "/lib"); 1835 } 1836 1837 // Add the appropriate client or server subdir 1838 len = strlen(buf); 1839 jrelib_p = buf + len; 1840 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1841 if (0 != access(buf, F_OK)) { 1842 snprintf(jrelib_p, buflen-len, "%s", ""); 1843 } 1844 1845 // If the path exists within JAVA_HOME, add the JVM library name 1846 // to complete the path to JVM being overridden. Otherwise fallback 1847 // to the path to the current library. 1848 if (0 == access(buf, F_OK)) { 1849 // Use current module name "libjvm" 1850 len = strlen(buf); 1851 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1852 } else { 1853 // Fall back to path of current library 1854 rp = realpath(dli_fname, buf); 1855 if (rp == NULL) 1856 return; 1857 } 1858 } 1859 } 1860 } 1861 1862 strcpy(saved_jvm_path, buf); 1863} 1864 1865void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1866 // no prefix required, not even "_" 1867} 1868 1869void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1870 // no suffix required 1871} 1872 1873//////////////////////////////////////////////////////////////////////////////// 1874// sun.misc.Signal support 1875 1876static volatile jint sigint_count = 0; 1877 1878static void 1879UserHandler(int sig, void *siginfo, void *context) { 1880 // 4511530 - sem_post is serialized and handled by the manager thread. When 1881 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1882 // don't want to flood the manager thread with sem_post requests. 1883 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1884 return; 1885 1886 // Ctrl-C is pressed during error reporting, likely because the error 1887 // handler fails to abort. Let VM die immediately. 1888 if (sig == SIGINT && is_error_reported()) { 1889 os::die(); 1890 } 1891 1892 os::signal_notify(sig); 1893} 1894 1895void* os::user_handler() { 1896 return CAST_FROM_FN_PTR(void*, UserHandler); 1897} 1898 1899extern "C" { 1900 typedef void (*sa_handler_t)(int); 1901 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1902} 1903 1904void* os::signal(int signal_number, void* handler) { 1905 struct sigaction sigAct, oldSigAct; 1906 1907 sigfillset(&(sigAct.sa_mask)); 1908 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1909 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1910 1911 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1912 // -1 means registration failed 1913 return (void *)-1; 1914 } 1915 1916 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1917} 1918 1919void os::signal_raise(int signal_number) { 1920 ::raise(signal_number); 1921} 1922 1923/* 1924 * The following code is moved from os.cpp for making this 1925 * code platform specific, which it is by its very nature. 1926 */ 1927 1928// Will be modified when max signal is changed to be dynamic 1929int os::sigexitnum_pd() { 1930 return NSIG; 1931} 1932 1933// a counter for each possible signal value 1934static volatile jint pending_signals[NSIG+1] = { 0 }; 1935 1936// Bsd(POSIX) specific hand shaking semaphore. 1937#ifdef __APPLE__ 1938typedef semaphore_t os_semaphore_t; 1939#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1940#define SEM_WAIT(sem) semaphore_wait(sem) 1941#define SEM_POST(sem) semaphore_signal(sem) 1942#define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1943#else 1944typedef sem_t os_semaphore_t; 1945#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1946#define SEM_WAIT(sem) sem_wait(&sem) 1947#define SEM_POST(sem) sem_post(&sem) 1948#define SEM_DESTROY(sem) sem_destroy(&sem) 1949#endif 1950 1951class Semaphore : public StackObj { 1952 public: 1953 Semaphore(); 1954 ~Semaphore(); 1955 void signal(); 1956 void wait(); 1957 bool trywait(); 1958 bool timedwait(unsigned int sec, int nsec); 1959 private: 1960 jlong currenttime() const; 1961 os_semaphore_t _semaphore; 1962}; 1963 1964Semaphore::Semaphore() : _semaphore(0) { 1965 SEM_INIT(_semaphore, 0); 1966} 1967 1968Semaphore::~Semaphore() { 1969 SEM_DESTROY(_semaphore); 1970} 1971 1972void Semaphore::signal() { 1973 SEM_POST(_semaphore); 1974} 1975 1976void Semaphore::wait() { 1977 SEM_WAIT(_semaphore); 1978} 1979 1980jlong Semaphore::currenttime() const { 1981 struct timeval tv; 1982 gettimeofday(&tv, NULL); 1983 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1984} 1985 1986#ifdef __APPLE__ 1987bool Semaphore::trywait() { 1988 return timedwait(0, 0); 1989} 1990 1991bool Semaphore::timedwait(unsigned int sec, int nsec) { 1992 kern_return_t kr = KERN_ABORTED; 1993 mach_timespec_t waitspec; 1994 waitspec.tv_sec = sec; 1995 waitspec.tv_nsec = nsec; 1996 1997 jlong starttime = currenttime(); 1998 1999 kr = semaphore_timedwait(_semaphore, waitspec); 2000 while (kr == KERN_ABORTED) { 2001 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 2002 2003 jlong current = currenttime(); 2004 jlong passedtime = current - starttime; 2005 2006 if (passedtime >= totalwait) { 2007 waitspec.tv_sec = 0; 2008 waitspec.tv_nsec = 0; 2009 } else { 2010 jlong waittime = totalwait - (current - starttime); 2011 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2012 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2013 } 2014 2015 kr = semaphore_timedwait(_semaphore, waitspec); 2016 } 2017 2018 return kr == KERN_SUCCESS; 2019} 2020 2021#else 2022 2023bool Semaphore::trywait() { 2024 return sem_trywait(&_semaphore) == 0; 2025} 2026 2027bool Semaphore::timedwait(unsigned int sec, int nsec) { 2028 struct timespec ts; 2029 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2030 2031 while (1) { 2032 int result = sem_timedwait(&_semaphore, &ts); 2033 if (result == 0) { 2034 return true; 2035 } else if (errno == EINTR) { 2036 continue; 2037 } else if (errno == ETIMEDOUT) { 2038 return false; 2039 } else { 2040 return false; 2041 } 2042 } 2043} 2044 2045#endif // __APPLE__ 2046 2047static os_semaphore_t sig_sem; 2048static Semaphore sr_semaphore; 2049 2050void os::signal_init_pd() { 2051 // Initialize signal structures 2052 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2053 2054 // Initialize signal semaphore 2055 ::SEM_INIT(sig_sem, 0); 2056} 2057 2058void os::signal_notify(int sig) { 2059 Atomic::inc(&pending_signals[sig]); 2060 ::SEM_POST(sig_sem); 2061} 2062 2063static int check_pending_signals(bool wait) { 2064 Atomic::store(0, &sigint_count); 2065 for (;;) { 2066 for (int i = 0; i < NSIG + 1; i++) { 2067 jint n = pending_signals[i]; 2068 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2069 return i; 2070 } 2071 } 2072 if (!wait) { 2073 return -1; 2074 } 2075 JavaThread *thread = JavaThread::current(); 2076 ThreadBlockInVM tbivm(thread); 2077 2078 bool threadIsSuspended; 2079 do { 2080 thread->set_suspend_equivalent(); 2081 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2082 ::SEM_WAIT(sig_sem); 2083 2084 // were we externally suspended while we were waiting? 2085 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2086 if (threadIsSuspended) { 2087 // 2088 // The semaphore has been incremented, but while we were waiting 2089 // another thread suspended us. We don't want to continue running 2090 // while suspended because that would surprise the thread that 2091 // suspended us. 2092 // 2093 ::SEM_POST(sig_sem); 2094 2095 thread->java_suspend_self(); 2096 } 2097 } while (threadIsSuspended); 2098 } 2099} 2100 2101int os::signal_lookup() { 2102 return check_pending_signals(false); 2103} 2104 2105int os::signal_wait() { 2106 return check_pending_signals(true); 2107} 2108 2109//////////////////////////////////////////////////////////////////////////////// 2110// Virtual Memory 2111 2112int os::vm_page_size() { 2113 // Seems redundant as all get out 2114 assert(os::Bsd::page_size() != -1, "must call os::init"); 2115 return os::Bsd::page_size(); 2116} 2117 2118// Solaris allocates memory by pages. 2119int os::vm_allocation_granularity() { 2120 assert(os::Bsd::page_size() != -1, "must call os::init"); 2121 return os::Bsd::page_size(); 2122} 2123 2124// Rationale behind this function: 2125// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2126// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2127// samples for JITted code. Here we create private executable mapping over the code cache 2128// and then we can use standard (well, almost, as mapping can change) way to provide 2129// info for the reporting script by storing timestamp and location of symbol 2130void bsd_wrap_code(char* base, size_t size) { 2131 static volatile jint cnt = 0; 2132 2133 if (!UseOprofile) { 2134 return; 2135 } 2136 2137 char buf[PATH_MAX + 1]; 2138 int num = Atomic::add(1, &cnt); 2139 2140 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2141 os::get_temp_directory(), os::current_process_id(), num); 2142 unlink(buf); 2143 2144 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2145 2146 if (fd != -1) { 2147 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2148 if (rv != (off_t)-1) { 2149 if (::write(fd, "", 1) == 1) { 2150 mmap(base, size, 2151 PROT_READ|PROT_WRITE|PROT_EXEC, 2152 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2153 } 2154 } 2155 ::close(fd); 2156 unlink(buf); 2157 } 2158} 2159 2160static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2161 int err) { 2162 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2163 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2164 strerror(err), err); 2165} 2166 2167// NOTE: Bsd kernel does not really reserve the pages for us. 2168// All it does is to check if there are enough free pages 2169// left at the time of mmap(). This could be a potential 2170// problem. 2171bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2172 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2173#ifdef __OpenBSD__ 2174 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2175 if (::mprotect(addr, size, prot) == 0) { 2176 return true; 2177 } 2178#else 2179 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2180 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2181 if (res != (uintptr_t) MAP_FAILED) { 2182 return true; 2183 } 2184#endif 2185 2186 // Warn about any commit errors we see in non-product builds just 2187 // in case mmap() doesn't work as described on the man page. 2188 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2189 2190 return false; 2191} 2192 2193bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2194 bool exec) { 2195 // alignment_hint is ignored on this OS 2196 return pd_commit_memory(addr, size, exec); 2197} 2198 2199void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2200 const char* mesg) { 2201 assert(mesg != NULL, "mesg must be specified"); 2202 if (!pd_commit_memory(addr, size, exec)) { 2203 // add extra info in product mode for vm_exit_out_of_memory(): 2204 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2205 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2206 } 2207} 2208 2209void os::pd_commit_memory_or_exit(char* addr, size_t size, 2210 size_t alignment_hint, bool exec, 2211 const char* mesg) { 2212 // alignment_hint is ignored on this OS 2213 pd_commit_memory_or_exit(addr, size, exec, mesg); 2214} 2215 2216void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2217} 2218 2219void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2220 ::madvise(addr, bytes, MADV_DONTNEED); 2221} 2222 2223void os::numa_make_global(char *addr, size_t bytes) { 2224} 2225 2226void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2227} 2228 2229bool os::numa_topology_changed() { return false; } 2230 2231size_t os::numa_get_groups_num() { 2232 return 1; 2233} 2234 2235int os::numa_get_group_id() { 2236 return 0; 2237} 2238 2239size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2240 if (size > 0) { 2241 ids[0] = 0; 2242 return 1; 2243 } 2244 return 0; 2245} 2246 2247bool os::get_page_info(char *start, page_info* info) { 2248 return false; 2249} 2250 2251char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2252 return end; 2253} 2254 2255 2256bool os::pd_uncommit_memory(char* addr, size_t size) { 2257#ifdef __OpenBSD__ 2258 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2259 return ::mprotect(addr, size, PROT_NONE) == 0; 2260#else 2261 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2262 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2263 return res != (uintptr_t) MAP_FAILED; 2264#endif 2265} 2266 2267bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2268 return os::commit_memory(addr, size, !ExecMem); 2269} 2270 2271// If this is a growable mapping, remove the guard pages entirely by 2272// munmap()ping them. If not, just call uncommit_memory(). 2273bool os::remove_stack_guard_pages(char* addr, size_t size) { 2274 return os::uncommit_memory(addr, size); 2275} 2276 2277static address _highest_vm_reserved_address = NULL; 2278 2279// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2280// at 'requested_addr'. If there are existing memory mappings at the same 2281// location, however, they will be overwritten. If 'fixed' is false, 2282// 'requested_addr' is only treated as a hint, the return value may or 2283// may not start from the requested address. Unlike Bsd mmap(), this 2284// function returns NULL to indicate failure. 2285static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2286 char * addr; 2287 int flags; 2288 2289 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2290 if (fixed) { 2291 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2292 flags |= MAP_FIXED; 2293 } 2294 2295 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2296 // touch an uncommitted page. Otherwise, the read/write might 2297 // succeed if we have enough swap space to back the physical page. 2298 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2299 flags, -1, 0); 2300 2301 if (addr != MAP_FAILED) { 2302 // anon_mmap() should only get called during VM initialization, 2303 // don't need lock (actually we can skip locking even it can be called 2304 // from multiple threads, because _highest_vm_reserved_address is just a 2305 // hint about the upper limit of non-stack memory regions.) 2306 if ((address)addr + bytes > _highest_vm_reserved_address) { 2307 _highest_vm_reserved_address = (address)addr + bytes; 2308 } 2309 } 2310 2311 return addr == MAP_FAILED ? NULL : addr; 2312} 2313 2314// Don't update _highest_vm_reserved_address, because there might be memory 2315// regions above addr + size. If so, releasing a memory region only creates 2316// a hole in the address space, it doesn't help prevent heap-stack collision. 2317// 2318static int anon_munmap(char * addr, size_t size) { 2319 return ::munmap(addr, size) == 0; 2320} 2321 2322char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2323 size_t alignment_hint) { 2324 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2325} 2326 2327bool os::pd_release_memory(char* addr, size_t size) { 2328 return anon_munmap(addr, size); 2329} 2330 2331static bool bsd_mprotect(char* addr, size_t size, int prot) { 2332 // Bsd wants the mprotect address argument to be page aligned. 2333 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2334 2335 // According to SUSv3, mprotect() should only be used with mappings 2336 // established by mmap(), and mmap() always maps whole pages. Unaligned 2337 // 'addr' likely indicates problem in the VM (e.g. trying to change 2338 // protection of malloc'ed or statically allocated memory). Check the 2339 // caller if you hit this assert. 2340 assert(addr == bottom, "sanity check"); 2341 2342 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2343 return ::mprotect(bottom, size, prot) == 0; 2344} 2345 2346// Set protections specified 2347bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2348 bool is_committed) { 2349 unsigned int p = 0; 2350 switch (prot) { 2351 case MEM_PROT_NONE: p = PROT_NONE; break; 2352 case MEM_PROT_READ: p = PROT_READ; break; 2353 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2354 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2355 default: 2356 ShouldNotReachHere(); 2357 } 2358 // is_committed is unused. 2359 return bsd_mprotect(addr, bytes, p); 2360} 2361 2362bool os::guard_memory(char* addr, size_t size) { 2363 return bsd_mprotect(addr, size, PROT_NONE); 2364} 2365 2366bool os::unguard_memory(char* addr, size_t size) { 2367 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2368} 2369 2370bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2371 return false; 2372} 2373 2374// Large page support 2375 2376static size_t _large_page_size = 0; 2377 2378void os::large_page_init() { 2379} 2380 2381 2382char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2383 fatal("This code is not used or maintained."); 2384 2385 // "exec" is passed in but not used. Creating the shared image for 2386 // the code cache doesn't have an SHM_X executable permission to check. 2387 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2388 2389 key_t key = IPC_PRIVATE; 2390 char *addr; 2391 2392 bool warn_on_failure = UseLargePages && 2393 (!FLAG_IS_DEFAULT(UseLargePages) || 2394 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2395 ); 2396 char msg[128]; 2397 2398 // Create a large shared memory region to attach to based on size. 2399 // Currently, size is the total size of the heap 2400 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2401 if (shmid == -1) { 2402 // Possible reasons for shmget failure: 2403 // 1. shmmax is too small for Java heap. 2404 // > check shmmax value: cat /proc/sys/kernel/shmmax 2405 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2406 // 2. not enough large page memory. 2407 // > check available large pages: cat /proc/meminfo 2408 // > increase amount of large pages: 2409 // echo new_value > /proc/sys/vm/nr_hugepages 2410 // Note 1: different Bsd may use different name for this property, 2411 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2412 // Note 2: it's possible there's enough physical memory available but 2413 // they are so fragmented after a long run that they can't 2414 // coalesce into large pages. Try to reserve large pages when 2415 // the system is still "fresh". 2416 if (warn_on_failure) { 2417 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 2418 warning(msg); 2419 } 2420 return NULL; 2421 } 2422 2423 // attach to the region 2424 addr = (char*)shmat(shmid, req_addr, 0); 2425 int err = errno; 2426 2427 // Remove shmid. If shmat() is successful, the actual shared memory segment 2428 // will be deleted when it's detached by shmdt() or when the process 2429 // terminates. If shmat() is not successful this will remove the shared 2430 // segment immediately. 2431 shmctl(shmid, IPC_RMID, NULL); 2432 2433 if ((intptr_t)addr == -1) { 2434 if (warn_on_failure) { 2435 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 2436 warning(msg); 2437 } 2438 return NULL; 2439 } 2440 2441 // The memory is committed 2442 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC); 2443 2444 return addr; 2445} 2446 2447bool os::release_memory_special(char* base, size_t bytes) { 2448 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2449 // detaching the SHM segment will also delete it, see reserve_memory_special() 2450 int rslt = shmdt(base); 2451 if (rslt == 0) { 2452 tkr.record((address)base, bytes); 2453 return true; 2454 } else { 2455 tkr.discard(); 2456 return false; 2457 } 2458 2459} 2460 2461size_t os::large_page_size() { 2462 return _large_page_size; 2463} 2464 2465// HugeTLBFS allows application to commit large page memory on demand; 2466// with SysV SHM the entire memory region must be allocated as shared 2467// memory. 2468bool os::can_commit_large_page_memory() { 2469 return UseHugeTLBFS; 2470} 2471 2472bool os::can_execute_large_page_memory() { 2473 return UseHugeTLBFS; 2474} 2475 2476// Reserve memory at an arbitrary address, only if that area is 2477// available (and not reserved for something else). 2478 2479char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2480 const int max_tries = 10; 2481 char* base[max_tries]; 2482 size_t size[max_tries]; 2483 const size_t gap = 0x000000; 2484 2485 // Assert only that the size is a multiple of the page size, since 2486 // that's all that mmap requires, and since that's all we really know 2487 // about at this low abstraction level. If we need higher alignment, 2488 // we can either pass an alignment to this method or verify alignment 2489 // in one of the methods further up the call chain. See bug 5044738. 2490 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2491 2492 // Repeatedly allocate blocks until the block is allocated at the 2493 // right spot. Give up after max_tries. Note that reserve_memory() will 2494 // automatically update _highest_vm_reserved_address if the call is 2495 // successful. The variable tracks the highest memory address every reserved 2496 // by JVM. It is used to detect heap-stack collision if running with 2497 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2498 // space than needed, it could confuse the collision detecting code. To 2499 // solve the problem, save current _highest_vm_reserved_address and 2500 // calculate the correct value before return. 2501 address old_highest = _highest_vm_reserved_address; 2502 2503 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2504 // if kernel honors the hint then we can return immediately. 2505 char * addr = anon_mmap(requested_addr, bytes, false); 2506 if (addr == requested_addr) { 2507 return requested_addr; 2508 } 2509 2510 if (addr != NULL) { 2511 // mmap() is successful but it fails to reserve at the requested address 2512 anon_munmap(addr, bytes); 2513 } 2514 2515 int i; 2516 for (i = 0; i < max_tries; ++i) { 2517 base[i] = reserve_memory(bytes); 2518 2519 if (base[i] != NULL) { 2520 // Is this the block we wanted? 2521 if (base[i] == requested_addr) { 2522 size[i] = bytes; 2523 break; 2524 } 2525 2526 // Does this overlap the block we wanted? Give back the overlapped 2527 // parts and try again. 2528 2529 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2530 if (top_overlap >= 0 && top_overlap < bytes) { 2531 unmap_memory(base[i], top_overlap); 2532 base[i] += top_overlap; 2533 size[i] = bytes - top_overlap; 2534 } else { 2535 size_t bottom_overlap = base[i] + bytes - requested_addr; 2536 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2537 unmap_memory(requested_addr, bottom_overlap); 2538 size[i] = bytes - bottom_overlap; 2539 } else { 2540 size[i] = bytes; 2541 } 2542 } 2543 } 2544 } 2545 2546 // Give back the unused reserved pieces. 2547 2548 for (int j = 0; j < i; ++j) { 2549 if (base[j] != NULL) { 2550 unmap_memory(base[j], size[j]); 2551 } 2552 } 2553 2554 if (i < max_tries) { 2555 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2556 return requested_addr; 2557 } else { 2558 _highest_vm_reserved_address = old_highest; 2559 return NULL; 2560 } 2561} 2562 2563size_t os::read(int fd, void *buf, unsigned int nBytes) { 2564 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2565} 2566 2567void os::naked_short_sleep(jlong ms) { 2568 struct timespec req; 2569 2570 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2571 req.tv_sec = 0; 2572 if (ms > 0) { 2573 req.tv_nsec = (ms % 1000) * 1000000; 2574 } 2575 else { 2576 req.tv_nsec = 1; 2577 } 2578 2579 nanosleep(&req, NULL); 2580 2581 return; 2582} 2583 2584// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2585void os::infinite_sleep() { 2586 while (true) { // sleep forever ... 2587 ::sleep(100); // ... 100 seconds at a time 2588 } 2589} 2590 2591// Used to convert frequent JVM_Yield() to nops 2592bool os::dont_yield() { 2593 return DontYieldALot; 2594} 2595 2596void os::yield() { 2597 sched_yield(); 2598} 2599 2600os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 2601 2602void os::yield_all() { 2603 // Yields to all threads, including threads with lower priorities 2604 // Threads on Bsd are all with same priority. The Solaris style 2605 // os::yield_all() with nanosleep(1ms) is not necessary. 2606 sched_yield(); 2607} 2608 2609//////////////////////////////////////////////////////////////////////////////// 2610// thread priority support 2611 2612// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2613// only supports dynamic priority, static priority must be zero. For real-time 2614// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2615// However, for large multi-threaded applications, SCHED_RR is not only slower 2616// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2617// of 5 runs - Sep 2005). 2618// 2619// The following code actually changes the niceness of kernel-thread/LWP. It 2620// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2621// not the entire user process, and user level threads are 1:1 mapped to kernel 2622// threads. It has always been the case, but could change in the future. For 2623// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2624// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2625 2626#if !defined(__APPLE__) 2627int os::java_to_os_priority[CriticalPriority + 1] = { 2628 19, // 0 Entry should never be used 2629 2630 0, // 1 MinPriority 2631 3, // 2 2632 6, // 3 2633 2634 10, // 4 2635 15, // 5 NormPriority 2636 18, // 6 2637 2638 21, // 7 2639 25, // 8 2640 28, // 9 NearMaxPriority 2641 2642 31, // 10 MaxPriority 2643 2644 31 // 11 CriticalPriority 2645}; 2646#else 2647/* Using Mach high-level priority assignments */ 2648int os::java_to_os_priority[CriticalPriority + 1] = { 2649 0, // 0 Entry should never be used (MINPRI_USER) 2650 2651 27, // 1 MinPriority 2652 28, // 2 2653 29, // 3 2654 2655 30, // 4 2656 31, // 5 NormPriority (BASEPRI_DEFAULT) 2657 32, // 6 2658 2659 33, // 7 2660 34, // 8 2661 35, // 9 NearMaxPriority 2662 2663 36, // 10 MaxPriority 2664 2665 36 // 11 CriticalPriority 2666}; 2667#endif 2668 2669static int prio_init() { 2670 if (ThreadPriorityPolicy == 1) { 2671 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2672 // if effective uid is not root. Perhaps, a more elegant way of doing 2673 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2674 if (geteuid() != 0) { 2675 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2676 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2677 } 2678 ThreadPriorityPolicy = 0; 2679 } 2680 } 2681 if (UseCriticalJavaThreadPriority) { 2682 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2683 } 2684 return 0; 2685} 2686 2687OSReturn os::set_native_priority(Thread* thread, int newpri) { 2688 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 2689 2690#ifdef __OpenBSD__ 2691 // OpenBSD pthread_setprio starves low priority threads 2692 return OS_OK; 2693#elif defined(__FreeBSD__) 2694 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2695#elif defined(__APPLE__) || defined(__NetBSD__) 2696 struct sched_param sp; 2697 int policy; 2698 pthread_t self = pthread_self(); 2699 2700 if (pthread_getschedparam(self, &policy, &sp) != 0) 2701 return OS_ERR; 2702 2703 sp.sched_priority = newpri; 2704 if (pthread_setschedparam(self, policy, &sp) != 0) 2705 return OS_ERR; 2706 2707 return OS_OK; 2708#else 2709 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2710 return (ret == 0) ? OS_OK : OS_ERR; 2711#endif 2712} 2713 2714OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2715 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 2716 *priority_ptr = java_to_os_priority[NormPriority]; 2717 return OS_OK; 2718 } 2719 2720 errno = 0; 2721#if defined(__OpenBSD__) || defined(__FreeBSD__) 2722 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2723#elif defined(__APPLE__) || defined(__NetBSD__) 2724 int policy; 2725 struct sched_param sp; 2726 2727 pthread_getschedparam(pthread_self(), &policy, &sp); 2728 *priority_ptr = sp.sched_priority; 2729#else 2730 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2731#endif 2732 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2733} 2734 2735// Hint to the underlying OS that a task switch would not be good. 2736// Void return because it's a hint and can fail. 2737void os::hint_no_preempt() {} 2738 2739//////////////////////////////////////////////////////////////////////////////// 2740// suspend/resume support 2741 2742// the low-level signal-based suspend/resume support is a remnant from the 2743// old VM-suspension that used to be for java-suspension, safepoints etc, 2744// within hotspot. Now there is a single use-case for this: 2745// - calling get_thread_pc() on the VMThread by the flat-profiler task 2746// that runs in the watcher thread. 2747// The remaining code is greatly simplified from the more general suspension 2748// code that used to be used. 2749// 2750// The protocol is quite simple: 2751// - suspend: 2752// - sends a signal to the target thread 2753// - polls the suspend state of the osthread using a yield loop 2754// - target thread signal handler (SR_handler) sets suspend state 2755// and blocks in sigsuspend until continued 2756// - resume: 2757// - sets target osthread state to continue 2758// - sends signal to end the sigsuspend loop in the SR_handler 2759// 2760// Note that the SR_lock plays no role in this suspend/resume protocol. 2761// 2762 2763static void resume_clear_context(OSThread *osthread) { 2764 osthread->set_ucontext(NULL); 2765 osthread->set_siginfo(NULL); 2766} 2767 2768static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2769 osthread->set_ucontext(context); 2770 osthread->set_siginfo(siginfo); 2771} 2772 2773// 2774// Handler function invoked when a thread's execution is suspended or 2775// resumed. We have to be careful that only async-safe functions are 2776// called here (Note: most pthread functions are not async safe and 2777// should be avoided.) 2778// 2779// Note: sigwait() is a more natural fit than sigsuspend() from an 2780// interface point of view, but sigwait() prevents the signal hander 2781// from being run. libpthread would get very confused by not having 2782// its signal handlers run and prevents sigwait()'s use with the 2783// mutex granting granting signal. 2784// 2785// Currently only ever called on the VMThread or JavaThread 2786// 2787static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2788 // Save and restore errno to avoid confusing native code with EINTR 2789 // after sigsuspend. 2790 int old_errno = errno; 2791 2792 Thread* thread = Thread::current(); 2793 OSThread* osthread = thread->osthread(); 2794 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2795 2796 os::SuspendResume::State current = osthread->sr.state(); 2797 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2798 suspend_save_context(osthread, siginfo, context); 2799 2800 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2801 os::SuspendResume::State state = osthread->sr.suspended(); 2802 if (state == os::SuspendResume::SR_SUSPENDED) { 2803 sigset_t suspend_set; // signals for sigsuspend() 2804 2805 // get current set of blocked signals and unblock resume signal 2806 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2807 sigdelset(&suspend_set, SR_signum); 2808 2809 sr_semaphore.signal(); 2810 // wait here until we are resumed 2811 while (1) { 2812 sigsuspend(&suspend_set); 2813 2814 os::SuspendResume::State result = osthread->sr.running(); 2815 if (result == os::SuspendResume::SR_RUNNING) { 2816 sr_semaphore.signal(); 2817 break; 2818 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2819 ShouldNotReachHere(); 2820 } 2821 } 2822 2823 } else if (state == os::SuspendResume::SR_RUNNING) { 2824 // request was cancelled, continue 2825 } else { 2826 ShouldNotReachHere(); 2827 } 2828 2829 resume_clear_context(osthread); 2830 } else if (current == os::SuspendResume::SR_RUNNING) { 2831 // request was cancelled, continue 2832 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2833 // ignore 2834 } else { 2835 // ignore 2836 } 2837 2838 errno = old_errno; 2839} 2840 2841 2842static int SR_initialize() { 2843 struct sigaction act; 2844 char *s; 2845 /* Get signal number to use for suspend/resume */ 2846 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2847 int sig = ::strtol(s, 0, 10); 2848 if (sig > 0 || sig < NSIG) { 2849 SR_signum = sig; 2850 } 2851 } 2852 2853 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2854 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2855 2856 sigemptyset(&SR_sigset); 2857 sigaddset(&SR_sigset, SR_signum); 2858 2859 /* Set up signal handler for suspend/resume */ 2860 act.sa_flags = SA_RESTART|SA_SIGINFO; 2861 act.sa_handler = (void (*)(int)) SR_handler; 2862 2863 // SR_signum is blocked by default. 2864 // 4528190 - We also need to block pthread restart signal (32 on all 2865 // supported Bsd platforms). Note that BsdThreads need to block 2866 // this signal for all threads to work properly. So we don't have 2867 // to use hard-coded signal number when setting up the mask. 2868 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2869 2870 if (sigaction(SR_signum, &act, 0) == -1) { 2871 return -1; 2872 } 2873 2874 // Save signal flag 2875 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2876 return 0; 2877} 2878 2879static int sr_notify(OSThread* osthread) { 2880 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2881 assert_status(status == 0, status, "pthread_kill"); 2882 return status; 2883} 2884 2885// "Randomly" selected value for how long we want to spin 2886// before bailing out on suspending a thread, also how often 2887// we send a signal to a thread we want to resume 2888static const int RANDOMLY_LARGE_INTEGER = 1000000; 2889static const int RANDOMLY_LARGE_INTEGER2 = 100; 2890 2891// returns true on success and false on error - really an error is fatal 2892// but this seems the normal response to library errors 2893static bool do_suspend(OSThread* osthread) { 2894 assert(osthread->sr.is_running(), "thread should be running"); 2895 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2896 2897 // mark as suspended and send signal 2898 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2899 // failed to switch, state wasn't running? 2900 ShouldNotReachHere(); 2901 return false; 2902 } 2903 2904 if (sr_notify(osthread) != 0) { 2905 ShouldNotReachHere(); 2906 } 2907 2908 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2909 while (true) { 2910 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2911 break; 2912 } else { 2913 // timeout 2914 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2915 if (cancelled == os::SuspendResume::SR_RUNNING) { 2916 return false; 2917 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2918 // make sure that we consume the signal on the semaphore as well 2919 sr_semaphore.wait(); 2920 break; 2921 } else { 2922 ShouldNotReachHere(); 2923 return false; 2924 } 2925 } 2926 } 2927 2928 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2929 return true; 2930} 2931 2932static void do_resume(OSThread* osthread) { 2933 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2934 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2935 2936 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2937 // failed to switch to WAKEUP_REQUEST 2938 ShouldNotReachHere(); 2939 return; 2940 } 2941 2942 while (true) { 2943 if (sr_notify(osthread) == 0) { 2944 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2945 if (osthread->sr.is_running()) { 2946 return; 2947 } 2948 } 2949 } else { 2950 ShouldNotReachHere(); 2951 } 2952 } 2953 2954 guarantee(osthread->sr.is_running(), "Must be running!"); 2955} 2956 2957/////////////////////////////////////////////////////////////////////////////////// 2958// signal handling (except suspend/resume) 2959 2960// This routine may be used by user applications as a "hook" to catch signals. 2961// The user-defined signal handler must pass unrecognized signals to this 2962// routine, and if it returns true (non-zero), then the signal handler must 2963// return immediately. If the flag "abort_if_unrecognized" is true, then this 2964// routine will never retun false (zero), but instead will execute a VM panic 2965// routine kill the process. 2966// 2967// If this routine returns false, it is OK to call it again. This allows 2968// the user-defined signal handler to perform checks either before or after 2969// the VM performs its own checks. Naturally, the user code would be making 2970// a serious error if it tried to handle an exception (such as a null check 2971// or breakpoint) that the VM was generating for its own correct operation. 2972// 2973// This routine may recognize any of the following kinds of signals: 2974// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2975// It should be consulted by handlers for any of those signals. 2976// 2977// The caller of this routine must pass in the three arguments supplied 2978// to the function referred to in the "sa_sigaction" (not the "sa_handler") 2979// field of the structure passed to sigaction(). This routine assumes that 2980// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2981// 2982// Note that the VM will print warnings if it detects conflicting signal 2983// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2984// 2985extern "C" JNIEXPORT int 2986JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2987 void* ucontext, int abort_if_unrecognized); 2988 2989void signalHandler(int sig, siginfo_t* info, void* uc) { 2990 assert(info != NULL && uc != NULL, "it must be old kernel"); 2991 int orig_errno = errno; // Preserve errno value over signal handler. 2992 JVM_handle_bsd_signal(sig, info, uc, true); 2993 errno = orig_errno; 2994} 2995 2996 2997// This boolean allows users to forward their own non-matching signals 2998// to JVM_handle_bsd_signal, harmlessly. 2999bool os::Bsd::signal_handlers_are_installed = false; 3000 3001// For signal-chaining 3002struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3003unsigned int os::Bsd::sigs = 0; 3004bool os::Bsd::libjsig_is_loaded = false; 3005typedef struct sigaction *(*get_signal_t)(int); 3006get_signal_t os::Bsd::get_signal_action = NULL; 3007 3008struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3009 struct sigaction *actp = NULL; 3010 3011 if (libjsig_is_loaded) { 3012 // Retrieve the old signal handler from libjsig 3013 actp = (*get_signal_action)(sig); 3014 } 3015 if (actp == NULL) { 3016 // Retrieve the preinstalled signal handler from jvm 3017 actp = get_preinstalled_handler(sig); 3018 } 3019 3020 return actp; 3021} 3022 3023static bool call_chained_handler(struct sigaction *actp, int sig, 3024 siginfo_t *siginfo, void *context) { 3025 // Call the old signal handler 3026 if (actp->sa_handler == SIG_DFL) { 3027 // It's more reasonable to let jvm treat it as an unexpected exception 3028 // instead of taking the default action. 3029 return false; 3030 } else if (actp->sa_handler != SIG_IGN) { 3031 if ((actp->sa_flags & SA_NODEFER) == 0) { 3032 // automaticlly block the signal 3033 sigaddset(&(actp->sa_mask), sig); 3034 } 3035 3036 sa_handler_t hand; 3037 sa_sigaction_t sa; 3038 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3039 // retrieve the chained handler 3040 if (siginfo_flag_set) { 3041 sa = actp->sa_sigaction; 3042 } else { 3043 hand = actp->sa_handler; 3044 } 3045 3046 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3047 actp->sa_handler = SIG_DFL; 3048 } 3049 3050 // try to honor the signal mask 3051 sigset_t oset; 3052 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3053 3054 // call into the chained handler 3055 if (siginfo_flag_set) { 3056 (*sa)(sig, siginfo, context); 3057 } else { 3058 (*hand)(sig); 3059 } 3060 3061 // restore the signal mask 3062 pthread_sigmask(SIG_SETMASK, &oset, 0); 3063 } 3064 // Tell jvm's signal handler the signal is taken care of. 3065 return true; 3066} 3067 3068bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3069 bool chained = false; 3070 // signal-chaining 3071 if (UseSignalChaining) { 3072 struct sigaction *actp = get_chained_signal_action(sig); 3073 if (actp != NULL) { 3074 chained = call_chained_handler(actp, sig, siginfo, context); 3075 } 3076 } 3077 return chained; 3078} 3079 3080struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3081 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 3082 return &sigact[sig]; 3083 } 3084 return NULL; 3085} 3086 3087void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3088 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3089 sigact[sig] = oldAct; 3090 sigs |= (unsigned int)1 << sig; 3091} 3092 3093// for diagnostic 3094int os::Bsd::sigflags[MAXSIGNUM]; 3095 3096int os::Bsd::get_our_sigflags(int sig) { 3097 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3098 return sigflags[sig]; 3099} 3100 3101void os::Bsd::set_our_sigflags(int sig, int flags) { 3102 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3103 sigflags[sig] = flags; 3104} 3105 3106void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3107 // Check for overwrite. 3108 struct sigaction oldAct; 3109 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3110 3111 void* oldhand = oldAct.sa_sigaction 3112 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3113 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3114 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3115 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3116 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3117 if (AllowUserSignalHandlers || !set_installed) { 3118 // Do not overwrite; user takes responsibility to forward to us. 3119 return; 3120 } else if (UseSignalChaining) { 3121 // save the old handler in jvm 3122 save_preinstalled_handler(sig, oldAct); 3123 // libjsig also interposes the sigaction() call below and saves the 3124 // old sigaction on it own. 3125 } else { 3126 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3127 "%#lx for signal %d.", (long)oldhand, sig)); 3128 } 3129 } 3130 3131 struct sigaction sigAct; 3132 sigfillset(&(sigAct.sa_mask)); 3133 sigAct.sa_handler = SIG_DFL; 3134 if (!set_installed) { 3135 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3136 } else { 3137 sigAct.sa_sigaction = signalHandler; 3138 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3139 } 3140#ifdef __APPLE__ 3141 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3142 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3143 // if the signal handler declares it will handle it on alternate stack. 3144 // Notice we only declare we will handle it on alt stack, but we are not 3145 // actually going to use real alt stack - this is just a workaround. 3146 // Please see ux_exception.c, method catch_mach_exception_raise for details 3147 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3148 if (sig == SIGSEGV) { 3149 sigAct.sa_flags |= SA_ONSTACK; 3150 } 3151#endif 3152 3153 // Save flags, which are set by ours 3154 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3155 sigflags[sig] = sigAct.sa_flags; 3156 3157 int ret = sigaction(sig, &sigAct, &oldAct); 3158 assert(ret == 0, "check"); 3159 3160 void* oldhand2 = oldAct.sa_sigaction 3161 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3162 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3163 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3164} 3165 3166// install signal handlers for signals that HotSpot needs to 3167// handle in order to support Java-level exception handling. 3168 3169void os::Bsd::install_signal_handlers() { 3170 if (!signal_handlers_are_installed) { 3171 signal_handlers_are_installed = true; 3172 3173 // signal-chaining 3174 typedef void (*signal_setting_t)(); 3175 signal_setting_t begin_signal_setting = NULL; 3176 signal_setting_t end_signal_setting = NULL; 3177 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3178 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3179 if (begin_signal_setting != NULL) { 3180 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3181 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3182 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3183 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3184 libjsig_is_loaded = true; 3185 assert(UseSignalChaining, "should enable signal-chaining"); 3186 } 3187 if (libjsig_is_loaded) { 3188 // Tell libjsig jvm is setting signal handlers 3189 (*begin_signal_setting)(); 3190 } 3191 3192 set_signal_handler(SIGSEGV, true); 3193 set_signal_handler(SIGPIPE, true); 3194 set_signal_handler(SIGBUS, true); 3195 set_signal_handler(SIGILL, true); 3196 set_signal_handler(SIGFPE, true); 3197 set_signal_handler(SIGXFSZ, true); 3198 3199#if defined(__APPLE__) 3200 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3201 // signals caught and handled by the JVM. To work around this, we reset the mach task 3202 // signal handler that's placed on our process by CrashReporter. This disables 3203 // CrashReporter-based reporting. 3204 // 3205 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3206 // on caught fatal signals. 3207 // 3208 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3209 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3210 // exception handling, while leaving the standard BSD signal handlers functional. 3211 kern_return_t kr; 3212 kr = task_set_exception_ports(mach_task_self(), 3213 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3214 MACH_PORT_NULL, 3215 EXCEPTION_STATE_IDENTITY, 3216 MACHINE_THREAD_STATE); 3217 3218 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3219#endif 3220 3221 if (libjsig_is_loaded) { 3222 // Tell libjsig jvm finishes setting signal handlers 3223 (*end_signal_setting)(); 3224 } 3225 3226 // We don't activate signal checker if libjsig is in place, we trust ourselves 3227 // and if UserSignalHandler is installed all bets are off 3228 if (CheckJNICalls) { 3229 if (libjsig_is_loaded) { 3230 if (PrintJNIResolving) { 3231 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3232 } 3233 check_signals = false; 3234 } 3235 if (AllowUserSignalHandlers) { 3236 if (PrintJNIResolving) { 3237 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3238 } 3239 check_signals = false; 3240 } 3241 } 3242 } 3243} 3244 3245 3246///// 3247// glibc on Bsd platform uses non-documented flag 3248// to indicate, that some special sort of signal 3249// trampoline is used. 3250// We will never set this flag, and we should 3251// ignore this flag in our diagnostic 3252#ifdef SIGNIFICANT_SIGNAL_MASK 3253#undef SIGNIFICANT_SIGNAL_MASK 3254#endif 3255#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3256 3257static const char* get_signal_handler_name(address handler, 3258 char* buf, int buflen) { 3259 int offset; 3260 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3261 if (found) { 3262 // skip directory names 3263 const char *p1, *p2; 3264 p1 = buf; 3265 size_t len = strlen(os::file_separator()); 3266 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3267 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3268 } else { 3269 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3270 } 3271 return buf; 3272} 3273 3274static void print_signal_handler(outputStream* st, int sig, 3275 char* buf, size_t buflen) { 3276 struct sigaction sa; 3277 3278 sigaction(sig, NULL, &sa); 3279 3280 // See comment for SIGNIFICANT_SIGNAL_MASK define 3281 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3282 3283 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3284 3285 address handler = (sa.sa_flags & SA_SIGINFO) 3286 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3287 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3288 3289 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3290 st->print("SIG_DFL"); 3291 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3292 st->print("SIG_IGN"); 3293 } else { 3294 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3295 } 3296 3297 st->print(", sa_mask[0]="); 3298 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3299 3300 address rh = VMError::get_resetted_sighandler(sig); 3301 // May be, handler was resetted by VMError? 3302 if(rh != NULL) { 3303 handler = rh; 3304 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3305 } 3306 3307 st->print(", sa_flags="); 3308 os::Posix::print_sa_flags(st, sa.sa_flags); 3309 3310 // Check: is it our handler? 3311 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3312 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3313 // It is our signal handler 3314 // check for flags, reset system-used one! 3315 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3316 st->print( 3317 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3318 os::Bsd::get_our_sigflags(sig)); 3319 } 3320 } 3321 st->cr(); 3322} 3323 3324 3325#define DO_SIGNAL_CHECK(sig) \ 3326 if (!sigismember(&check_signal_done, sig)) \ 3327 os::Bsd::check_signal_handler(sig) 3328 3329// This method is a periodic task to check for misbehaving JNI applications 3330// under CheckJNI, we can add any periodic checks here 3331 3332void os::run_periodic_checks() { 3333 3334 if (check_signals == false) return; 3335 3336 // SEGV and BUS if overridden could potentially prevent 3337 // generation of hs*.log in the event of a crash, debugging 3338 // such a case can be very challenging, so we absolutely 3339 // check the following for a good measure: 3340 DO_SIGNAL_CHECK(SIGSEGV); 3341 DO_SIGNAL_CHECK(SIGILL); 3342 DO_SIGNAL_CHECK(SIGFPE); 3343 DO_SIGNAL_CHECK(SIGBUS); 3344 DO_SIGNAL_CHECK(SIGPIPE); 3345 DO_SIGNAL_CHECK(SIGXFSZ); 3346 3347 3348 // ReduceSignalUsage allows the user to override these handlers 3349 // see comments at the very top and jvm_solaris.h 3350 if (!ReduceSignalUsage) { 3351 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3352 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3353 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3354 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3355 } 3356 3357 DO_SIGNAL_CHECK(SR_signum); 3358 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3359} 3360 3361typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3362 3363static os_sigaction_t os_sigaction = NULL; 3364 3365void os::Bsd::check_signal_handler(int sig) { 3366 char buf[O_BUFLEN]; 3367 address jvmHandler = NULL; 3368 3369 3370 struct sigaction act; 3371 if (os_sigaction == NULL) { 3372 // only trust the default sigaction, in case it has been interposed 3373 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3374 if (os_sigaction == NULL) return; 3375 } 3376 3377 os_sigaction(sig, (struct sigaction*)NULL, &act); 3378 3379 3380 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3381 3382 address thisHandler = (act.sa_flags & SA_SIGINFO) 3383 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3384 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 3385 3386 3387 switch(sig) { 3388 case SIGSEGV: 3389 case SIGBUS: 3390 case SIGFPE: 3391 case SIGPIPE: 3392 case SIGILL: 3393 case SIGXFSZ: 3394 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3395 break; 3396 3397 case SHUTDOWN1_SIGNAL: 3398 case SHUTDOWN2_SIGNAL: 3399 case SHUTDOWN3_SIGNAL: 3400 case BREAK_SIGNAL: 3401 jvmHandler = (address)user_handler(); 3402 break; 3403 3404 case INTERRUPT_SIGNAL: 3405 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3406 break; 3407 3408 default: 3409 if (sig == SR_signum) { 3410 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3411 } else { 3412 return; 3413 } 3414 break; 3415 } 3416 3417 if (thisHandler != jvmHandler) { 3418 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3419 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3420 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3421 // No need to check this sig any longer 3422 sigaddset(&check_signal_done, sig); 3423 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3424 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3425 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3426 exception_name(sig, buf, O_BUFLEN)); 3427 } 3428 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3429 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3430 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3431 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3432 // No need to check this sig any longer 3433 sigaddset(&check_signal_done, sig); 3434 } 3435 3436 // Dump all the signal 3437 if (sigismember(&check_signal_done, sig)) { 3438 print_signal_handlers(tty, buf, O_BUFLEN); 3439 } 3440} 3441 3442extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3443 3444extern bool signal_name(int signo, char* buf, size_t len); 3445 3446const char* os::exception_name(int exception_code, char* buf, size_t size) { 3447 if (0 < exception_code && exception_code <= SIGRTMAX) { 3448 // signal 3449 if (!signal_name(exception_code, buf, size)) { 3450 jio_snprintf(buf, size, "SIG%d", exception_code); 3451 } 3452 return buf; 3453 } else { 3454 return NULL; 3455 } 3456} 3457 3458// this is called _before_ the most of global arguments have been parsed 3459void os::init(void) { 3460 char dummy; /* used to get a guess on initial stack address */ 3461// first_hrtime = gethrtime(); 3462 3463 // With BsdThreads the JavaMain thread pid (primordial thread) 3464 // is different than the pid of the java launcher thread. 3465 // So, on Bsd, the launcher thread pid is passed to the VM 3466 // via the sun.java.launcher.pid property. 3467 // Use this property instead of getpid() if it was correctly passed. 3468 // See bug 6351349. 3469 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3470 3471 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3472 3473 clock_tics_per_sec = CLK_TCK; 3474 3475 init_random(1234567); 3476 3477 ThreadCritical::initialize(); 3478 3479 Bsd::set_page_size(getpagesize()); 3480 if (Bsd::page_size() == -1) { 3481 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3482 strerror(errno))); 3483 } 3484 init_page_sizes((size_t) Bsd::page_size()); 3485 3486 Bsd::initialize_system_info(); 3487 3488 // main_thread points to the aboriginal thread 3489 Bsd::_main_thread = pthread_self(); 3490 3491 Bsd::clock_init(); 3492 initial_time_count = javaTimeNanos(); 3493 3494#ifdef __APPLE__ 3495 // XXXDARWIN 3496 // Work around the unaligned VM callbacks in hotspot's 3497 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3498 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3499 // alignment when doing symbol lookup. To work around this, we force early 3500 // binding of all symbols now, thus binding when alignment is known-good. 3501 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3502#endif 3503} 3504 3505// To install functions for atexit system call 3506extern "C" { 3507 static void perfMemory_exit_helper() { 3508 perfMemory_exit(); 3509 } 3510} 3511 3512// this is called _after_ the global arguments have been parsed 3513jint os::init_2(void) 3514{ 3515 // Allocate a single page and mark it as readable for safepoint polling 3516 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3517 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 3518 3519 os::set_polling_page( polling_page ); 3520 3521#ifndef PRODUCT 3522 if(Verbose && PrintMiscellaneous) 3523 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3524#endif 3525 3526 if (!UseMembar) { 3527 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3528 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3529 os::set_memory_serialize_page( mem_serialize_page ); 3530 3531#ifndef PRODUCT 3532 if(Verbose && PrintMiscellaneous) 3533 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3534#endif 3535 } 3536 3537 // initialize suspend/resume support - must do this before signal_sets_init() 3538 if (SR_initialize() != 0) { 3539 perror("SR_initialize failed"); 3540 return JNI_ERR; 3541 } 3542 3543 Bsd::signal_sets_init(); 3544 Bsd::install_signal_handlers(); 3545 3546 // Check minimum allowable stack size for thread creation and to initialize 3547 // the java system classes, including StackOverflowError - depends on page 3548 // size. Add a page for compiler2 recursion in main thread. 3549 // Add in 2*BytesPerWord times page size to account for VM stack during 3550 // class initialization depending on 32 or 64 bit VM. 3551 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3552 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3553 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3554 3555 size_t threadStackSizeInBytes = ThreadStackSize * K; 3556 if (threadStackSizeInBytes != 0 && 3557 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3558 tty->print_cr("\nThe stack size specified is too small, " 3559 "Specify at least %dk", 3560 os::Bsd::min_stack_allowed/ K); 3561 return JNI_ERR; 3562 } 3563 3564 // Make the stack size a multiple of the page size so that 3565 // the yellow/red zones can be guarded. 3566 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3567 vm_page_size())); 3568 3569 if (MaxFDLimit) { 3570 // set the number of file descriptors to max. print out error 3571 // if getrlimit/setrlimit fails but continue regardless. 3572 struct rlimit nbr_files; 3573 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3574 if (status != 0) { 3575 if (PrintMiscellaneous && (Verbose || WizardMode)) 3576 perror("os::init_2 getrlimit failed"); 3577 } else { 3578 nbr_files.rlim_cur = nbr_files.rlim_max; 3579 3580#ifdef __APPLE__ 3581 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3582 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3583 // be used instead 3584 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3585#endif 3586 3587 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3588 if (status != 0) { 3589 if (PrintMiscellaneous && (Verbose || WizardMode)) 3590 perror("os::init_2 setrlimit failed"); 3591 } 3592 } 3593 } 3594 3595 // at-exit methods are called in the reverse order of their registration. 3596 // atexit functions are called on return from main or as a result of a 3597 // call to exit(3C). There can be only 32 of these functions registered 3598 // and atexit() does not set errno. 3599 3600 if (PerfAllowAtExitRegistration) { 3601 // only register atexit functions if PerfAllowAtExitRegistration is set. 3602 // atexit functions can be delayed until process exit time, which 3603 // can be problematic for embedded VM situations. Embedded VMs should 3604 // call DestroyJavaVM() to assure that VM resources are released. 3605 3606 // note: perfMemory_exit_helper atexit function may be removed in 3607 // the future if the appropriate cleanup code can be added to the 3608 // VM_Exit VMOperation's doit method. 3609 if (atexit(perfMemory_exit_helper) != 0) { 3610 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3611 } 3612 } 3613 3614 // initialize thread priority policy 3615 prio_init(); 3616 3617#ifdef __APPLE__ 3618 // dynamically link to objective c gc registration 3619 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3620 if (handleLibObjc != NULL) { 3621 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3622 } 3623#endif 3624 3625 return JNI_OK; 3626} 3627 3628// this is called at the end of vm_initialization 3629void os::init_3(void) { } 3630 3631// Mark the polling page as unreadable 3632void os::make_polling_page_unreadable(void) { 3633 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 3634 fatal("Could not disable polling page"); 3635}; 3636 3637// Mark the polling page as readable 3638void os::make_polling_page_readable(void) { 3639 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3640 fatal("Could not enable polling page"); 3641 } 3642}; 3643 3644int os::active_processor_count() { 3645 return _processor_count; 3646} 3647 3648void os::set_native_thread_name(const char *name) { 3649#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3650 // This is only supported in Snow Leopard and beyond 3651 if (name != NULL) { 3652 // Add a "Java: " prefix to the name 3653 char buf[MAXTHREADNAMESIZE]; 3654 snprintf(buf, sizeof(buf), "Java: %s", name); 3655 pthread_setname_np(buf); 3656 } 3657#endif 3658} 3659 3660bool os::distribute_processes(uint length, uint* distribution) { 3661 // Not yet implemented. 3662 return false; 3663} 3664 3665bool os::bind_to_processor(uint processor_id) { 3666 // Not yet implemented. 3667 return false; 3668} 3669 3670void os::SuspendedThreadTask::internal_do_task() { 3671 if (do_suspend(_thread->osthread())) { 3672 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3673 do_task(context); 3674 do_resume(_thread->osthread()); 3675 } 3676} 3677 3678/// 3679class PcFetcher : public os::SuspendedThreadTask { 3680public: 3681 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3682 ExtendedPC result(); 3683protected: 3684 void do_task(const os::SuspendedThreadTaskContext& context); 3685private: 3686 ExtendedPC _epc; 3687}; 3688 3689ExtendedPC PcFetcher::result() { 3690 guarantee(is_done(), "task is not done yet."); 3691 return _epc; 3692} 3693 3694void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3695 Thread* thread = context.thread(); 3696 OSThread* osthread = thread->osthread(); 3697 if (osthread->ucontext() != NULL) { 3698 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3699 } else { 3700 // NULL context is unexpected, double-check this is the VMThread 3701 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3702 } 3703} 3704 3705// Suspends the target using the signal mechanism and then grabs the PC before 3706// resuming the target. Used by the flat-profiler only 3707ExtendedPC os::get_thread_pc(Thread* thread) { 3708 // Make sure that it is called by the watcher for the VMThread 3709 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3710 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3711 3712 PcFetcher fetcher(thread); 3713 fetcher.run(); 3714 return fetcher.result(); 3715} 3716 3717int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3718{ 3719 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3720} 3721 3722//////////////////////////////////////////////////////////////////////////////// 3723// debug support 3724 3725bool os::find(address addr, outputStream* st) { 3726 Dl_info dlinfo; 3727 memset(&dlinfo, 0, sizeof(dlinfo)); 3728 if (dladdr(addr, &dlinfo) != 0) { 3729 st->print(PTR_FORMAT ": ", addr); 3730 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3731 st->print("%s+%#x", dlinfo.dli_sname, 3732 addr - (intptr_t)dlinfo.dli_saddr); 3733 } else if (dlinfo.dli_fbase != NULL) { 3734 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3735 } else { 3736 st->print("<absolute address>"); 3737 } 3738 if (dlinfo.dli_fname != NULL) { 3739 st->print(" in %s", dlinfo.dli_fname); 3740 } 3741 if (dlinfo.dli_fbase != NULL) { 3742 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3743 } 3744 st->cr(); 3745 3746 if (Verbose) { 3747 // decode some bytes around the PC 3748 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3749 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3750 address lowest = (address) dlinfo.dli_sname; 3751 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3752 if (begin < lowest) begin = lowest; 3753 Dl_info dlinfo2; 3754 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3755 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3756 end = (address) dlinfo2.dli_saddr; 3757 Disassembler::decode(begin, end, st); 3758 } 3759 return true; 3760 } 3761 return false; 3762} 3763 3764//////////////////////////////////////////////////////////////////////////////// 3765// misc 3766 3767// This does not do anything on Bsd. This is basically a hook for being 3768// able to use structured exception handling (thread-local exception filters) 3769// on, e.g., Win32. 3770void 3771os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3772 JavaCallArguments* args, Thread* thread) { 3773 f(value, method, args, thread); 3774} 3775 3776void os::print_statistics() { 3777} 3778 3779int os::message_box(const char* title, const char* message) { 3780 int i; 3781 fdStream err(defaultStream::error_fd()); 3782 for (i = 0; i < 78; i++) err.print_raw("="); 3783 err.cr(); 3784 err.print_raw_cr(title); 3785 for (i = 0; i < 78; i++) err.print_raw("-"); 3786 err.cr(); 3787 err.print_raw_cr(message); 3788 for (i = 0; i < 78; i++) err.print_raw("="); 3789 err.cr(); 3790 3791 char buf[16]; 3792 // Prevent process from exiting upon "read error" without consuming all CPU 3793 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3794 3795 return buf[0] == 'y' || buf[0] == 'Y'; 3796} 3797 3798int os::stat(const char *path, struct stat *sbuf) { 3799 char pathbuf[MAX_PATH]; 3800 if (strlen(path) > MAX_PATH - 1) { 3801 errno = ENAMETOOLONG; 3802 return -1; 3803 } 3804 os::native_path(strcpy(pathbuf, path)); 3805 return ::stat(pathbuf, sbuf); 3806} 3807 3808bool os::check_heap(bool force) { 3809 return true; 3810} 3811 3812int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 3813 return ::vsnprintf(buf, count, format, args); 3814} 3815 3816// Is a (classpath) directory empty? 3817bool os::dir_is_empty(const char* path) { 3818 DIR *dir = NULL; 3819 struct dirent *ptr; 3820 3821 dir = opendir(path); 3822 if (dir == NULL) return true; 3823 3824 /* Scan the directory */ 3825 bool result = true; 3826 char buf[sizeof(struct dirent) + MAX_PATH]; 3827 while (result && (ptr = ::readdir(dir)) != NULL) { 3828 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3829 result = false; 3830 } 3831 } 3832 closedir(dir); 3833 return result; 3834} 3835 3836// This code originates from JDK's sysOpen and open64_w 3837// from src/solaris/hpi/src/system_md.c 3838 3839#ifndef O_DELETE 3840#define O_DELETE 0x10000 3841#endif 3842 3843// Open a file. Unlink the file immediately after open returns 3844// if the specified oflag has the O_DELETE flag set. 3845// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3846 3847int os::open(const char *path, int oflag, int mode) { 3848 3849 if (strlen(path) > MAX_PATH - 1) { 3850 errno = ENAMETOOLONG; 3851 return -1; 3852 } 3853 int fd; 3854 int o_delete = (oflag & O_DELETE); 3855 oflag = oflag & ~O_DELETE; 3856 3857 fd = ::open(path, oflag, mode); 3858 if (fd == -1) return -1; 3859 3860 //If the open succeeded, the file might still be a directory 3861 { 3862 struct stat buf; 3863 int ret = ::fstat(fd, &buf); 3864 int st_mode = buf.st_mode; 3865 3866 if (ret != -1) { 3867 if ((st_mode & S_IFMT) == S_IFDIR) { 3868 errno = EISDIR; 3869 ::close(fd); 3870 return -1; 3871 } 3872 } else { 3873 ::close(fd); 3874 return -1; 3875 } 3876 } 3877 3878 /* 3879 * All file descriptors that are opened in the JVM and not 3880 * specifically destined for a subprocess should have the 3881 * close-on-exec flag set. If we don't set it, then careless 3rd 3882 * party native code might fork and exec without closing all 3883 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3884 * UNIXProcess.c), and this in turn might: 3885 * 3886 * - cause end-of-file to fail to be detected on some file 3887 * descriptors, resulting in mysterious hangs, or 3888 * 3889 * - might cause an fopen in the subprocess to fail on a system 3890 * suffering from bug 1085341. 3891 * 3892 * (Yes, the default setting of the close-on-exec flag is a Unix 3893 * design flaw) 3894 * 3895 * See: 3896 * 1085341: 32-bit stdio routines should support file descriptors >255 3897 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3898 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3899 */ 3900#ifdef FD_CLOEXEC 3901 { 3902 int flags = ::fcntl(fd, F_GETFD); 3903 if (flags != -1) 3904 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3905 } 3906#endif 3907 3908 if (o_delete != 0) { 3909 ::unlink(path); 3910 } 3911 return fd; 3912} 3913 3914 3915// create binary file, rewriting existing file if required 3916int os::create_binary_file(const char* path, bool rewrite_existing) { 3917 int oflags = O_WRONLY | O_CREAT; 3918 if (!rewrite_existing) { 3919 oflags |= O_EXCL; 3920 } 3921 return ::open(path, oflags, S_IREAD | S_IWRITE); 3922} 3923 3924// return current position of file pointer 3925jlong os::current_file_offset(int fd) { 3926 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3927} 3928 3929// move file pointer to the specified offset 3930jlong os::seek_to_file_offset(int fd, jlong offset) { 3931 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3932} 3933 3934// This code originates from JDK's sysAvailable 3935// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3936 3937int os::available(int fd, jlong *bytes) { 3938 jlong cur, end; 3939 int mode; 3940 struct stat buf; 3941 3942 if (::fstat(fd, &buf) >= 0) { 3943 mode = buf.st_mode; 3944 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3945 /* 3946 * XXX: is the following call interruptible? If so, this might 3947 * need to go through the INTERRUPT_IO() wrapper as for other 3948 * blocking, interruptible calls in this file. 3949 */ 3950 int n; 3951 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3952 *bytes = n; 3953 return 1; 3954 } 3955 } 3956 } 3957 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3958 return 0; 3959 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3960 return 0; 3961 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3962 return 0; 3963 } 3964 *bytes = end - cur; 3965 return 1; 3966} 3967 3968int os::socket_available(int fd, jint *pbytes) { 3969 if (fd < 0) 3970 return OS_OK; 3971 3972 int ret; 3973 3974 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 3975 3976 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 3977 // is expected to return 0 on failure and 1 on success to the jdk. 3978 3979 return (ret == OS_ERR) ? 0 : 1; 3980} 3981 3982// Map a block of memory. 3983char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3984 char *addr, size_t bytes, bool read_only, 3985 bool allow_exec) { 3986 int prot; 3987 int flags; 3988 3989 if (read_only) { 3990 prot = PROT_READ; 3991 flags = MAP_SHARED; 3992 } else { 3993 prot = PROT_READ | PROT_WRITE; 3994 flags = MAP_PRIVATE; 3995 } 3996 3997 if (allow_exec) { 3998 prot |= PROT_EXEC; 3999 } 4000 4001 if (addr != NULL) { 4002 flags |= MAP_FIXED; 4003 } 4004 4005 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4006 fd, file_offset); 4007 if (mapped_address == MAP_FAILED) { 4008 return NULL; 4009 } 4010 return mapped_address; 4011} 4012 4013 4014// Remap a block of memory. 4015char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4016 char *addr, size_t bytes, bool read_only, 4017 bool allow_exec) { 4018 // same as map_memory() on this OS 4019 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4020 allow_exec); 4021} 4022 4023 4024// Unmap a block of memory. 4025bool os::pd_unmap_memory(char* addr, size_t bytes) { 4026 return munmap(addr, bytes) == 0; 4027} 4028 4029// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4030// are used by JVM M&M and JVMTI to get user+sys or user CPU time 4031// of a thread. 4032// 4033// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4034// the fast estimate available on the platform. 4035 4036jlong os::current_thread_cpu_time() { 4037#ifdef __APPLE__ 4038 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4039#else 4040 Unimplemented(); 4041 return 0; 4042#endif 4043} 4044 4045jlong os::thread_cpu_time(Thread* thread) { 4046#ifdef __APPLE__ 4047 return os::thread_cpu_time(thread, true /* user + sys */); 4048#else 4049 Unimplemented(); 4050 return 0; 4051#endif 4052} 4053 4054jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4055#ifdef __APPLE__ 4056 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4057#else 4058 Unimplemented(); 4059 return 0; 4060#endif 4061} 4062 4063jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4064#ifdef __APPLE__ 4065 struct thread_basic_info tinfo; 4066 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4067 kern_return_t kr; 4068 thread_t mach_thread; 4069 4070 mach_thread = thread->osthread()->thread_id(); 4071 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4072 if (kr != KERN_SUCCESS) 4073 return -1; 4074 4075 if (user_sys_cpu_time) { 4076 jlong nanos; 4077 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4078 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4079 return nanos; 4080 } else { 4081 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4082 } 4083#else 4084 Unimplemented(); 4085 return 0; 4086#endif 4087} 4088 4089 4090void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4091 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4092 info_ptr->may_skip_backward = false; // elapsed time not wall time 4093 info_ptr->may_skip_forward = false; // elapsed time not wall time 4094 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4095} 4096 4097void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4098 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4099 info_ptr->may_skip_backward = false; // elapsed time not wall time 4100 info_ptr->may_skip_forward = false; // elapsed time not wall time 4101 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4102} 4103 4104bool os::is_thread_cpu_time_supported() { 4105#ifdef __APPLE__ 4106 return true; 4107#else 4108 return false; 4109#endif 4110} 4111 4112// System loadavg support. Returns -1 if load average cannot be obtained. 4113// Bsd doesn't yet have a (official) notion of processor sets, 4114// so just return the system wide load average. 4115int os::loadavg(double loadavg[], int nelem) { 4116 return ::getloadavg(loadavg, nelem); 4117} 4118 4119void os::pause() { 4120 char filename[MAX_PATH]; 4121 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4122 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4123 } else { 4124 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4125 } 4126 4127 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4128 if (fd != -1) { 4129 struct stat buf; 4130 ::close(fd); 4131 while (::stat(filename, &buf) == 0) { 4132 (void)::poll(NULL, 0, 100); 4133 } 4134 } else { 4135 jio_fprintf(stderr, 4136 "Could not open pause file '%s', continuing immediately.\n", filename); 4137 } 4138} 4139 4140 4141// Refer to the comments in os_solaris.cpp park-unpark. 4142// 4143// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4144// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4145// For specifics regarding the bug see GLIBC BUGID 261237 : 4146// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4147// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4148// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4149// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4150// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4151// and monitorenter when we're using 1-0 locking. All those operations may result in 4152// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4153// of libpthread avoids the problem, but isn't practical. 4154// 4155// Possible remedies: 4156// 4157// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4158// This is palliative and probabilistic, however. If the thread is preempted 4159// between the call to compute_abstime() and pthread_cond_timedwait(), more 4160// than the minimum period may have passed, and the abstime may be stale (in the 4161// past) resultin in a hang. Using this technique reduces the odds of a hang 4162// but the JVM is still vulnerable, particularly on heavily loaded systems. 4163// 4164// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4165// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4166// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4167// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4168// thread. 4169// 4170// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4171// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4172// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4173// This also works well. In fact it avoids kernel-level scalability impediments 4174// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4175// timers in a graceful fashion. 4176// 4177// 4. When the abstime value is in the past it appears that control returns 4178// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4179// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4180// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4181// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4182// It may be possible to avoid reinitialization by checking the return 4183// value from pthread_cond_timedwait(). In addition to reinitializing the 4184// condvar we must establish the invariant that cond_signal() is only called 4185// within critical sections protected by the adjunct mutex. This prevents 4186// cond_signal() from "seeing" a condvar that's in the midst of being 4187// reinitialized or that is corrupt. Sadly, this invariant obviates the 4188// desirable signal-after-unlock optimization that avoids futile context switching. 4189// 4190// I'm also concerned that some versions of NTPL might allocate an auxilliary 4191// structure when a condvar is used or initialized. cond_destroy() would 4192// release the helper structure. Our reinitialize-after-timedwait fix 4193// put excessive stress on malloc/free and locks protecting the c-heap. 4194// 4195// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4196// It may be possible to refine (4) by checking the kernel and NTPL verisons 4197// and only enabling the work-around for vulnerable environments. 4198 4199// utility to compute the abstime argument to timedwait: 4200// millis is the relative timeout time 4201// abstime will be the absolute timeout time 4202// TODO: replace compute_abstime() with unpackTime() 4203 4204static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4205 if (millis < 0) millis = 0; 4206 struct timeval now; 4207 int status = gettimeofday(&now, NULL); 4208 assert(status == 0, "gettimeofday"); 4209 jlong seconds = millis / 1000; 4210 millis %= 1000; 4211 if (seconds > 50000000) { // see man cond_timedwait(3T) 4212 seconds = 50000000; 4213 } 4214 abstime->tv_sec = now.tv_sec + seconds; 4215 long usec = now.tv_usec + millis * 1000; 4216 if (usec >= 1000000) { 4217 abstime->tv_sec += 1; 4218 usec -= 1000000; 4219 } 4220 abstime->tv_nsec = usec * 1000; 4221 return abstime; 4222} 4223 4224 4225// Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 4226// Conceptually TryPark() should be equivalent to park(0). 4227 4228int os::PlatformEvent::TryPark() { 4229 for (;;) { 4230 const int v = _Event ; 4231 guarantee ((v == 0) || (v == 1), "invariant") ; 4232 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 4233 } 4234} 4235 4236void os::PlatformEvent::park() { // AKA "down()" 4237 // Invariant: Only the thread associated with the Event/PlatformEvent 4238 // may call park(). 4239 // TODO: assert that _Assoc != NULL or _Assoc == Self 4240 int v ; 4241 for (;;) { 4242 v = _Event ; 4243 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4244 } 4245 guarantee (v >= 0, "invariant") ; 4246 if (v == 0) { 4247 // Do this the hard way by blocking ... 4248 int status = pthread_mutex_lock(_mutex); 4249 assert_status(status == 0, status, "mutex_lock"); 4250 guarantee (_nParked == 0, "invariant") ; 4251 ++ _nParked ; 4252 while (_Event < 0) { 4253 status = pthread_cond_wait(_cond, _mutex); 4254 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4255 // Treat this the same as if the wait was interrupted 4256 if (status == ETIMEDOUT) { status = EINTR; } 4257 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4258 } 4259 -- _nParked ; 4260 4261 _Event = 0 ; 4262 status = pthread_mutex_unlock(_mutex); 4263 assert_status(status == 0, status, "mutex_unlock"); 4264 // Paranoia to ensure our locked and lock-free paths interact 4265 // correctly with each other. 4266 OrderAccess::fence(); 4267 } 4268 guarantee (_Event >= 0, "invariant") ; 4269} 4270 4271int os::PlatformEvent::park(jlong millis) { 4272 guarantee (_nParked == 0, "invariant") ; 4273 4274 int v ; 4275 for (;;) { 4276 v = _Event ; 4277 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 4278 } 4279 guarantee (v >= 0, "invariant") ; 4280 if (v != 0) return OS_OK ; 4281 4282 // We do this the hard way, by blocking the thread. 4283 // Consider enforcing a minimum timeout value. 4284 struct timespec abst; 4285 compute_abstime(&abst, millis); 4286 4287 int ret = OS_TIMEOUT; 4288 int status = pthread_mutex_lock(_mutex); 4289 assert_status(status == 0, status, "mutex_lock"); 4290 guarantee (_nParked == 0, "invariant") ; 4291 ++_nParked ; 4292 4293 // Object.wait(timo) will return because of 4294 // (a) notification 4295 // (b) timeout 4296 // (c) thread.interrupt 4297 // 4298 // Thread.interrupt and object.notify{All} both call Event::set. 4299 // That is, we treat thread.interrupt as a special case of notification. 4300 // The underlying Solaris implementation, cond_timedwait, admits 4301 // spurious/premature wakeups, but the JLS/JVM spec prevents the 4302 // JVM from making those visible to Java code. As such, we must 4303 // filter out spurious wakeups. We assume all ETIME returns are valid. 4304 // 4305 // TODO: properly differentiate simultaneous notify+interrupt. 4306 // In that case, we should propagate the notify to another waiter. 4307 4308 while (_Event < 0) { 4309 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4310 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4311 pthread_cond_destroy (_cond); 4312 pthread_cond_init (_cond, NULL) ; 4313 } 4314 assert_status(status == 0 || status == EINTR || 4315 status == ETIMEDOUT, 4316 status, "cond_timedwait"); 4317 if (!FilterSpuriousWakeups) break ; // previous semantics 4318 if (status == ETIMEDOUT) break ; 4319 // We consume and ignore EINTR and spurious wakeups. 4320 } 4321 --_nParked ; 4322 if (_Event >= 0) { 4323 ret = OS_OK; 4324 } 4325 _Event = 0 ; 4326 status = pthread_mutex_unlock(_mutex); 4327 assert_status(status == 0, status, "mutex_unlock"); 4328 assert (_nParked == 0, "invariant") ; 4329 // Paranoia to ensure our locked and lock-free paths interact 4330 // correctly with each other. 4331 OrderAccess::fence(); 4332 return ret; 4333} 4334 4335void os::PlatformEvent::unpark() { 4336 // Transitions for _Event: 4337 // 0 :=> 1 4338 // 1 :=> 1 4339 // -1 :=> either 0 or 1; must signal target thread 4340 // That is, we can safely transition _Event from -1 to either 4341 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back 4342 // unpark() calls. 4343 // See also: "Semaphores in Plan 9" by Mullender & Cox 4344 // 4345 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4346 // that it will take two back-to-back park() calls for the owning 4347 // thread to block. This has the benefit of forcing a spurious return 4348 // from the first park() call after an unpark() call which will help 4349 // shake out uses of park() and unpark() without condition variables. 4350 4351 if (Atomic::xchg(1, &_Event) >= 0) return; 4352 4353 // Wait for the thread associated with the event to vacate 4354 int status = pthread_mutex_lock(_mutex); 4355 assert_status(status == 0, status, "mutex_lock"); 4356 int AnyWaiters = _nParked; 4357 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4358 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4359 AnyWaiters = 0; 4360 pthread_cond_signal(_cond); 4361 } 4362 status = pthread_mutex_unlock(_mutex); 4363 assert_status(status == 0, status, "mutex_unlock"); 4364 if (AnyWaiters != 0) { 4365 status = pthread_cond_signal(_cond); 4366 assert_status(status == 0, status, "cond_signal"); 4367 } 4368 4369 // Note that we signal() _after dropping the lock for "immortal" Events. 4370 // This is safe and avoids a common class of futile wakeups. In rare 4371 // circumstances this can cause a thread to return prematurely from 4372 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4373 // simply re-test the condition and re-park itself. 4374} 4375 4376 4377// JSR166 4378// ------------------------------------------------------- 4379 4380/* 4381 * The solaris and bsd implementations of park/unpark are fairly 4382 * conservative for now, but can be improved. They currently use a 4383 * mutex/condvar pair, plus a a count. 4384 * Park decrements count if > 0, else does a condvar wait. Unpark 4385 * sets count to 1 and signals condvar. Only one thread ever waits 4386 * on the condvar. Contention seen when trying to park implies that someone 4387 * is unparking you, so don't wait. And spurious returns are fine, so there 4388 * is no need to track notifications. 4389 */ 4390 4391#define MAX_SECS 100000000 4392/* 4393 * This code is common to bsd and solaris and will be moved to a 4394 * common place in dolphin. 4395 * 4396 * The passed in time value is either a relative time in nanoseconds 4397 * or an absolute time in milliseconds. Either way it has to be unpacked 4398 * into suitable seconds and nanoseconds components and stored in the 4399 * given timespec structure. 4400 * Given time is a 64-bit value and the time_t used in the timespec is only 4401 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4402 * overflow if times way in the future are given. Further on Solaris versions 4403 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4404 * number of seconds, in abstime, is less than current_time + 100,000,000. 4405 * As it will be 28 years before "now + 100000000" will overflow we can 4406 * ignore overflow and just impose a hard-limit on seconds using the value 4407 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4408 * years from "now". 4409 */ 4410 4411static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4412 assert (time > 0, "convertTime"); 4413 4414 struct timeval now; 4415 int status = gettimeofday(&now, NULL); 4416 assert(status == 0, "gettimeofday"); 4417 4418 time_t max_secs = now.tv_sec + MAX_SECS; 4419 4420 if (isAbsolute) { 4421 jlong secs = time / 1000; 4422 if (secs > max_secs) { 4423 absTime->tv_sec = max_secs; 4424 } 4425 else { 4426 absTime->tv_sec = secs; 4427 } 4428 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4429 } 4430 else { 4431 jlong secs = time / NANOSECS_PER_SEC; 4432 if (secs >= MAX_SECS) { 4433 absTime->tv_sec = max_secs; 4434 absTime->tv_nsec = 0; 4435 } 4436 else { 4437 absTime->tv_sec = now.tv_sec + secs; 4438 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4439 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4440 absTime->tv_nsec -= NANOSECS_PER_SEC; 4441 ++absTime->tv_sec; // note: this must be <= max_secs 4442 } 4443 } 4444 } 4445 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4446 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4447 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4448 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4449} 4450 4451void Parker::park(bool isAbsolute, jlong time) { 4452 // Ideally we'd do something useful while spinning, such 4453 // as calling unpackTime(). 4454 4455 // Optional fast-path check: 4456 // Return immediately if a permit is available. 4457 // We depend on Atomic::xchg() having full barrier semantics 4458 // since we are doing a lock-free update to _counter. 4459 if (Atomic::xchg(0, &_counter) > 0) return; 4460 4461 Thread* thread = Thread::current(); 4462 assert(thread->is_Java_thread(), "Must be JavaThread"); 4463 JavaThread *jt = (JavaThread *)thread; 4464 4465 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4466 // Check interrupt before trying to wait 4467 if (Thread::is_interrupted(thread, false)) { 4468 return; 4469 } 4470 4471 // Next, demultiplex/decode time arguments 4472 struct timespec absTime; 4473 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 4474 return; 4475 } 4476 if (time > 0) { 4477 unpackTime(&absTime, isAbsolute, time); 4478 } 4479 4480 4481 // Enter safepoint region 4482 // Beware of deadlocks such as 6317397. 4483 // The per-thread Parker:: mutex is a classic leaf-lock. 4484 // In particular a thread must never block on the Threads_lock while 4485 // holding the Parker:: mutex. If safepoints are pending both the 4486 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4487 ThreadBlockInVM tbivm(jt); 4488 4489 // Don't wait if cannot get lock since interference arises from 4490 // unblocking. Also. check interrupt before trying wait 4491 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4492 return; 4493 } 4494 4495 int status ; 4496 if (_counter > 0) { // no wait needed 4497 _counter = 0; 4498 status = pthread_mutex_unlock(_mutex); 4499 assert (status == 0, "invariant") ; 4500 // Paranoia to ensure our locked and lock-free paths interact 4501 // correctly with each other and Java-level accesses. 4502 OrderAccess::fence(); 4503 return; 4504 } 4505 4506#ifdef ASSERT 4507 // Don't catch signals while blocked; let the running threads have the signals. 4508 // (This allows a debugger to break into the running thread.) 4509 sigset_t oldsigs; 4510 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4511 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4512#endif 4513 4514 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4515 jt->set_suspend_equivalent(); 4516 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4517 4518 if (time == 0) { 4519 status = pthread_cond_wait (_cond, _mutex) ; 4520 } else { 4521 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 4522 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4523 pthread_cond_destroy (_cond) ; 4524 pthread_cond_init (_cond, NULL); 4525 } 4526 } 4527 assert_status(status == 0 || status == EINTR || 4528 status == ETIMEDOUT, 4529 status, "cond_timedwait"); 4530 4531#ifdef ASSERT 4532 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4533#endif 4534 4535 _counter = 0 ; 4536 status = pthread_mutex_unlock(_mutex) ; 4537 assert_status(status == 0, status, "invariant") ; 4538 // Paranoia to ensure our locked and lock-free paths interact 4539 // correctly with each other and Java-level accesses. 4540 OrderAccess::fence(); 4541 4542 // If externally suspended while waiting, re-suspend 4543 if (jt->handle_special_suspend_equivalent_condition()) { 4544 jt->java_suspend_self(); 4545 } 4546} 4547 4548void Parker::unpark() { 4549 int s, status ; 4550 status = pthread_mutex_lock(_mutex); 4551 assert (status == 0, "invariant") ; 4552 s = _counter; 4553 _counter = 1; 4554 if (s < 1) { 4555 if (WorkAroundNPTLTimedWaitHang) { 4556 status = pthread_cond_signal (_cond) ; 4557 assert (status == 0, "invariant") ; 4558 status = pthread_mutex_unlock(_mutex); 4559 assert (status == 0, "invariant") ; 4560 } else { 4561 status = pthread_mutex_unlock(_mutex); 4562 assert (status == 0, "invariant") ; 4563 status = pthread_cond_signal (_cond) ; 4564 assert (status == 0, "invariant") ; 4565 } 4566 } else { 4567 pthread_mutex_unlock(_mutex); 4568 assert (status == 0, "invariant") ; 4569 } 4570} 4571 4572 4573/* Darwin has no "environ" in a dynamic library. */ 4574#ifdef __APPLE__ 4575#include <crt_externs.h> 4576#define environ (*_NSGetEnviron()) 4577#else 4578extern char** environ; 4579#endif 4580 4581// Run the specified command in a separate process. Return its exit value, 4582// or -1 on failure (e.g. can't fork a new process). 4583// Unlike system(), this function can be called from signal handler. It 4584// doesn't block SIGINT et al. 4585int os::fork_and_exec(char* cmd) { 4586 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4587 4588 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4589 // pthread_atfork handlers and reset pthread library. All we need is a 4590 // separate process to execve. Make a direct syscall to fork process. 4591 // On IA64 there's no fork syscall, we have to use fork() and hope for 4592 // the best... 4593 pid_t pid = fork(); 4594 4595 if (pid < 0) { 4596 // fork failed 4597 return -1; 4598 4599 } else if (pid == 0) { 4600 // child process 4601 4602 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4603 // first to kill every thread on the thread list. Because this list is 4604 // not reset by fork() (see notes above), execve() will instead kill 4605 // every thread in the parent process. We know this is the only thread 4606 // in the new process, so make a system call directly. 4607 // IA64 should use normal execve() from glibc to match the glibc fork() 4608 // above. 4609 execve("/bin/sh", (char* const*)argv, environ); 4610 4611 // execve failed 4612 _exit(-1); 4613 4614 } else { 4615 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4616 // care about the actual exit code, for now. 4617 4618 int status; 4619 4620 // Wait for the child process to exit. This returns immediately if 4621 // the child has already exited. */ 4622 while (waitpid(pid, &status, 0) < 0) { 4623 switch (errno) { 4624 case ECHILD: return 0; 4625 case EINTR: break; 4626 default: return -1; 4627 } 4628 } 4629 4630 if (WIFEXITED(status)) { 4631 // The child exited normally; get its exit code. 4632 return WEXITSTATUS(status); 4633 } else if (WIFSIGNALED(status)) { 4634 // The child exited because of a signal 4635 // The best value to return is 0x80 + signal number, 4636 // because that is what all Unix shells do, and because 4637 // it allows callers to distinguish between process exit and 4638 // process death by signal. 4639 return 0x80 + WTERMSIG(status); 4640 } else { 4641 // Unknown exit code; pass it through 4642 return status; 4643 } 4644 } 4645} 4646 4647// is_headless_jre() 4648// 4649// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4650// in order to report if we are running in a headless jre 4651// 4652// Since JDK8 xawt/libmawt.so was moved into the same directory 4653// as libawt.so, and renamed libawt_xawt.so 4654// 4655bool os::is_headless_jre() { 4656#ifdef __APPLE__ 4657 // We no longer build headless-only on Mac OS X 4658 return false; 4659#else 4660 struct stat statbuf; 4661 char buf[MAXPATHLEN]; 4662 char libmawtpath[MAXPATHLEN]; 4663 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4664 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4665 char *p; 4666 4667 // Get path to libjvm.so 4668 os::jvm_path(buf, sizeof(buf)); 4669 4670 // Get rid of libjvm.so 4671 p = strrchr(buf, '/'); 4672 if (p == NULL) return false; 4673 else *p = '\0'; 4674 4675 // Get rid of client or server 4676 p = strrchr(buf, '/'); 4677 if (p == NULL) return false; 4678 else *p = '\0'; 4679 4680 // check xawt/libmawt.so 4681 strcpy(libmawtpath, buf); 4682 strcat(libmawtpath, xawtstr); 4683 if (::stat(libmawtpath, &statbuf) == 0) return false; 4684 4685 // check libawt_xawt.so 4686 strcpy(libmawtpath, buf); 4687 strcat(libmawtpath, new_xawtstr); 4688 if (::stat(libmawtpath, &statbuf) == 0) return false; 4689 4690 return true; 4691#endif 4692} 4693 4694// Get the default path to the core file 4695// Returns the length of the string 4696int os::get_core_path(char* buffer, size_t bufferSize) { 4697 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4698 4699 // Truncate if theoretical string was longer than bufferSize 4700 n = MIN2(n, (int)bufferSize); 4701 4702 return n; 4703} 4704 4705#ifndef PRODUCT 4706void TestReserveMemorySpecial_test() { 4707 // No tests available for this platform 4708} 4709#endif 4710