os_bsd.cpp revision 9651:f7dc8eebc3f5
1/* 2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25// no precompiled headers 26#include "classfile/classLoader.hpp" 27#include "classfile/systemDictionary.hpp" 28#include "classfile/vmSymbols.hpp" 29#include "code/icBuffer.hpp" 30#include "code/vtableStubs.hpp" 31#include "compiler/compileBroker.hpp" 32#include "compiler/disassembler.hpp" 33#include "interpreter/interpreter.hpp" 34#include "jvm_bsd.h" 35#include "memory/allocation.inline.hpp" 36#include "memory/filemap.hpp" 37#include "mutex_bsd.inline.hpp" 38#include "oops/oop.inline.hpp" 39#include "os_bsd.inline.hpp" 40#include "os_share_bsd.hpp" 41#include "prims/jniFastGetField.hpp" 42#include "prims/jvm.h" 43#include "prims/jvm_misc.hpp" 44#include "runtime/arguments.hpp" 45#include "runtime/atomic.inline.hpp" 46#include "runtime/extendedPC.hpp" 47#include "runtime/globals.hpp" 48#include "runtime/interfaceSupport.hpp" 49#include "runtime/java.hpp" 50#include "runtime/javaCalls.hpp" 51#include "runtime/mutexLocker.hpp" 52#include "runtime/objectMonitor.hpp" 53#include "runtime/orderAccess.inline.hpp" 54#include "runtime/osThread.hpp" 55#include "runtime/perfMemory.hpp" 56#include "runtime/sharedRuntime.hpp" 57#include "runtime/statSampler.hpp" 58#include "runtime/stubRoutines.hpp" 59#include "runtime/thread.inline.hpp" 60#include "runtime/threadCritical.hpp" 61#include "runtime/timer.hpp" 62#include "semaphore_bsd.hpp" 63#include "services/attachListener.hpp" 64#include "services/memTracker.hpp" 65#include "services/runtimeService.hpp" 66#include "utilities/decoder.hpp" 67#include "utilities/defaultStream.hpp" 68#include "utilities/events.hpp" 69#include "utilities/growableArray.hpp" 70#include "utilities/vmError.hpp" 71 72// put OS-includes here 73# include <sys/types.h> 74# include <sys/mman.h> 75# include <sys/stat.h> 76# include <sys/select.h> 77# include <pthread.h> 78# include <signal.h> 79# include <errno.h> 80# include <dlfcn.h> 81# include <stdio.h> 82# include <unistd.h> 83# include <sys/resource.h> 84# include <pthread.h> 85# include <sys/stat.h> 86# include <sys/time.h> 87# include <sys/times.h> 88# include <sys/utsname.h> 89# include <sys/socket.h> 90# include <sys/wait.h> 91# include <time.h> 92# include <pwd.h> 93# include <poll.h> 94# include <semaphore.h> 95# include <fcntl.h> 96# include <string.h> 97# include <sys/param.h> 98# include <sys/sysctl.h> 99# include <sys/ipc.h> 100# include <sys/shm.h> 101#ifndef __APPLE__ 102# include <link.h> 103#endif 104# include <stdint.h> 105# include <inttypes.h> 106# include <sys/ioctl.h> 107# include <sys/syscall.h> 108 109#if defined(__FreeBSD__) || defined(__NetBSD__) 110 #include <elf.h> 111#endif 112 113#ifdef __APPLE__ 114 #include <mach/mach.h> // semaphore_* API 115 #include <mach-o/dyld.h> 116 #include <sys/proc_info.h> 117 #include <objc/objc-auto.h> 118#endif 119 120#ifndef MAP_ANONYMOUS 121 #define MAP_ANONYMOUS MAP_ANON 122#endif 123 124#define MAX_PATH (2 * K) 125 126// for timer info max values which include all bits 127#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 128 129#define LARGEPAGES_BIT (1 << 6) 130 131//////////////////////////////////////////////////////////////////////////////// 132// global variables 133julong os::Bsd::_physical_memory = 0; 134 135#ifdef __APPLE__ 136mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 137volatile uint64_t os::Bsd::_max_abstime = 0; 138#else 139int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 140#endif 141pthread_t os::Bsd::_main_thread; 142int os::Bsd::_page_size = -1; 143 144static jlong initial_time_count=0; 145 146static int clock_tics_per_sec = 100; 147 148// For diagnostics to print a message once. see run_periodic_checks 149static sigset_t check_signal_done; 150static bool check_signals = true; 151 152static pid_t _initial_pid = 0; 153 154// Signal number used to suspend/resume a thread 155 156// do not use any signal number less than SIGSEGV, see 4355769 157static int SR_signum = SIGUSR2; 158sigset_t SR_sigset; 159 160 161//////////////////////////////////////////////////////////////////////////////// 162// utility functions 163 164static int SR_initialize(); 165static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 166 167julong os::available_memory() { 168 return Bsd::available_memory(); 169} 170 171// available here means free 172julong os::Bsd::available_memory() { 173 uint64_t available = physical_memory() >> 2; 174#ifdef __APPLE__ 175 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 176 vm_statistics64_data_t vmstat; 177 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 178 (host_info64_t)&vmstat, &count); 179 assert(kerr == KERN_SUCCESS, 180 "host_statistics64 failed - check mach_host_self() and count"); 181 if (kerr == KERN_SUCCESS) { 182 available = vmstat.free_count * os::vm_page_size(); 183 } 184#endif 185 return available; 186} 187 188julong os::physical_memory() { 189 return Bsd::physical_memory(); 190} 191 192// Return true if user is running as root. 193 194bool os::have_special_privileges() { 195 static bool init = false; 196 static bool privileges = false; 197 if (!init) { 198 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 199 init = true; 200 } 201 return privileges; 202} 203 204 205 206// Cpu architecture string 207#if defined(ZERO) 208static char cpu_arch[] = ZERO_LIBARCH; 209#elif defined(IA64) 210static char cpu_arch[] = "ia64"; 211#elif defined(IA32) 212static char cpu_arch[] = "i386"; 213#elif defined(AMD64) 214static char cpu_arch[] = "amd64"; 215#elif defined(ARM) 216static char cpu_arch[] = "arm"; 217#elif defined(PPC32) 218static char cpu_arch[] = "ppc"; 219#elif defined(SPARC) 220 #ifdef _LP64 221static char cpu_arch[] = "sparcv9"; 222 #else 223static char cpu_arch[] = "sparc"; 224 #endif 225#else 226 #error Add appropriate cpu_arch setting 227#endif 228 229// Compiler variant 230#ifdef COMPILER2 231 #define COMPILER_VARIANT "server" 232#else 233 #define COMPILER_VARIANT "client" 234#endif 235 236 237void os::Bsd::initialize_system_info() { 238 int mib[2]; 239 size_t len; 240 int cpu_val; 241 julong mem_val; 242 243 // get processors count via hw.ncpus sysctl 244 mib[0] = CTL_HW; 245 mib[1] = HW_NCPU; 246 len = sizeof(cpu_val); 247 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 248 assert(len == sizeof(cpu_val), "unexpected data size"); 249 set_processor_count(cpu_val); 250 } else { 251 set_processor_count(1); // fallback 252 } 253 254 // get physical memory via hw.memsize sysctl (hw.memsize is used 255 // since it returns a 64 bit value) 256 mib[0] = CTL_HW; 257 258#if defined (HW_MEMSIZE) // Apple 259 mib[1] = HW_MEMSIZE; 260#elif defined(HW_PHYSMEM) // Most of BSD 261 mib[1] = HW_PHYSMEM; 262#elif defined(HW_REALMEM) // Old FreeBSD 263 mib[1] = HW_REALMEM; 264#else 265 #error No ways to get physmem 266#endif 267 268 len = sizeof(mem_val); 269 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 270 assert(len == sizeof(mem_val), "unexpected data size"); 271 _physical_memory = mem_val; 272 } else { 273 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?) 274 } 275 276#ifdef __OpenBSD__ 277 { 278 // limit _physical_memory memory view on OpenBSD since 279 // datasize rlimit restricts us anyway. 280 struct rlimit limits; 281 getrlimit(RLIMIT_DATA, &limits); 282 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 283 } 284#endif 285} 286 287#ifdef __APPLE__ 288static const char *get_home() { 289 const char *home_dir = ::getenv("HOME"); 290 if ((home_dir == NULL) || (*home_dir == '\0')) { 291 struct passwd *passwd_info = getpwuid(geteuid()); 292 if (passwd_info != NULL) { 293 home_dir = passwd_info->pw_dir; 294 } 295 } 296 297 return home_dir; 298} 299#endif 300 301void os::init_system_properties_values() { 302 // The next steps are taken in the product version: 303 // 304 // Obtain the JAVA_HOME value from the location of libjvm.so. 305 // This library should be located at: 306 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 307 // 308 // If "/jre/lib/" appears at the right place in the path, then we 309 // assume libjvm.so is installed in a JDK and we use this path. 310 // 311 // Otherwise exit with message: "Could not create the Java virtual machine." 312 // 313 // The following extra steps are taken in the debugging version: 314 // 315 // If "/jre/lib/" does NOT appear at the right place in the path 316 // instead of exit check for $JAVA_HOME environment variable. 317 // 318 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 319 // then we append a fake suffix "hotspot/libjvm.so" to this path so 320 // it looks like libjvm.so is installed there 321 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 322 // 323 // Otherwise exit. 324 // 325 // Important note: if the location of libjvm.so changes this 326 // code needs to be changed accordingly. 327 328 // See ld(1): 329 // The linker uses the following search paths to locate required 330 // shared libraries: 331 // 1: ... 332 // ... 333 // 7: The default directories, normally /lib and /usr/lib. 334#ifndef DEFAULT_LIBPATH 335 #define DEFAULT_LIBPATH "/lib:/usr/lib" 336#endif 337 338// Base path of extensions installed on the system. 339#define SYS_EXT_DIR "/usr/java/packages" 340#define EXTENSIONS_DIR "/lib/ext" 341 342#ifndef __APPLE__ 343 344 // Buffer that fits several sprintfs. 345 // Note that the space for the colon and the trailing null are provided 346 // by the nulls included by the sizeof operator. 347 const size_t bufsize = 348 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends. 349 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir 350 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 351 352 // sysclasspath, java_home, dll_dir 353 { 354 char *pslash; 355 os::jvm_path(buf, bufsize); 356 357 // Found the full path to libjvm.so. 358 // Now cut the path to <java_home>/jre if we can. 359 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 360 pslash = strrchr(buf, '/'); 361 if (pslash != NULL) { 362 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 363 } 364 Arguments::set_dll_dir(buf); 365 366 if (pslash != NULL) { 367 pslash = strrchr(buf, '/'); 368 if (pslash != NULL) { 369 *pslash = '\0'; // Get rid of /<arch>. 370 pslash = strrchr(buf, '/'); 371 if (pslash != NULL) { 372 *pslash = '\0'; // Get rid of /lib. 373 } 374 } 375 } 376 Arguments::set_java_home(buf); 377 set_boot_path('/', ':'); 378 } 379 380 // Where to look for native libraries. 381 // 382 // Note: Due to a legacy implementation, most of the library path 383 // is set in the launcher. This was to accomodate linking restrictions 384 // on legacy Bsd implementations (which are no longer supported). 385 // Eventually, all the library path setting will be done here. 386 // 387 // However, to prevent the proliferation of improperly built native 388 // libraries, the new path component /usr/java/packages is added here. 389 // Eventually, all the library path setting will be done here. 390 { 391 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 392 // should always exist (until the legacy problem cited above is 393 // addressed). 394 const char *v = ::getenv("LD_LIBRARY_PATH"); 395 const char *v_colon = ":"; 396 if (v == NULL) { v = ""; v_colon = ""; } 397 // That's +1 for the colon and +1 for the trailing '\0'. 398 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 399 strlen(v) + 1 + 400 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 401 mtInternal); 402 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 403 Arguments::set_library_path(ld_library_path); 404 FREE_C_HEAP_ARRAY(char, ld_library_path); 405 } 406 407 // Extensions directories. 408 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 409 Arguments::set_ext_dirs(buf); 410 411 FREE_C_HEAP_ARRAY(char, buf); 412 413#else // __APPLE__ 414 415 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 416 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 417 418 const char *user_home_dir = get_home(); 419 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 420 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 421 sizeof(SYS_EXTENSIONS_DIRS); 422 423 // Buffer that fits several sprintfs. 424 // Note that the space for the colon and the trailing null are provided 425 // by the nulls included by the sizeof operator. 426 const size_t bufsize = 427 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends. 428 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir 429 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 430 431 // sysclasspath, java_home, dll_dir 432 { 433 char *pslash; 434 os::jvm_path(buf, bufsize); 435 436 // Found the full path to libjvm.so. 437 // Now cut the path to <java_home>/jre if we can. 438 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 439 pslash = strrchr(buf, '/'); 440 if (pslash != NULL) { 441 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 442 } 443#ifdef STATIC_BUILD 444 strcat(buf, "/lib"); 445#endif 446 447 Arguments::set_dll_dir(buf); 448 449 if (pslash != NULL) { 450 pslash = strrchr(buf, '/'); 451 if (pslash != NULL) { 452 *pslash = '\0'; // Get rid of /lib. 453 } 454 } 455 Arguments::set_java_home(buf); 456 set_boot_path('/', ':'); 457 } 458 459 // Where to look for native libraries. 460 // 461 // Note: Due to a legacy implementation, most of the library path 462 // is set in the launcher. This was to accomodate linking restrictions 463 // on legacy Bsd implementations (which are no longer supported). 464 // Eventually, all the library path setting will be done here. 465 // 466 // However, to prevent the proliferation of improperly built native 467 // libraries, the new path component /usr/java/packages is added here. 468 // Eventually, all the library path setting will be done here. 469 { 470 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 471 // should always exist (until the legacy problem cited above is 472 // addressed). 473 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 474 // can specify a directory inside an app wrapper 475 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 476 const char *l_colon = ":"; 477 if (l == NULL) { l = ""; l_colon = ""; } 478 479 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 480 const char *v_colon = ":"; 481 if (v == NULL) { v = ""; v_colon = ""; } 482 483 // Apple's Java6 has "." at the beginning of java.library.path. 484 // OpenJDK on Windows has "." at the end of java.library.path. 485 // OpenJDK on Linux and Solaris don't have "." in java.library.path 486 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 487 // "." is appended to the end of java.library.path. Yes, this 488 // could cause a change in behavior, but Apple's Java6 behavior 489 // can be achieved by putting "." at the beginning of the 490 // JAVA_LIBRARY_PATH environment variable. 491 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 492 strlen(v) + 1 + strlen(l) + 1 + 493 system_ext_size + 3, 494 mtInternal); 495 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 496 v, v_colon, l, l_colon, user_home_dir); 497 Arguments::set_library_path(ld_library_path); 498 FREE_C_HEAP_ARRAY(char, ld_library_path); 499 } 500 501 // Extensions directories. 502 // 503 // Note that the space for the colon and the trailing null are provided 504 // by the nulls included by the sizeof operator (so actually one byte more 505 // than necessary is allocated). 506 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 507 user_home_dir, Arguments::get_java_home()); 508 Arguments::set_ext_dirs(buf); 509 510 FREE_C_HEAP_ARRAY(char, buf); 511 512#undef SYS_EXTENSIONS_DIR 513#undef SYS_EXTENSIONS_DIRS 514 515#endif // __APPLE__ 516 517#undef SYS_EXT_DIR 518#undef EXTENSIONS_DIR 519} 520 521//////////////////////////////////////////////////////////////////////////////// 522// breakpoint support 523 524void os::breakpoint() { 525 BREAKPOINT; 526} 527 528extern "C" void breakpoint() { 529 // use debugger to set breakpoint here 530} 531 532//////////////////////////////////////////////////////////////////////////////// 533// signal support 534 535debug_only(static bool signal_sets_initialized = false); 536static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 537 538bool os::Bsd::is_sig_ignored(int sig) { 539 struct sigaction oact; 540 sigaction(sig, (struct sigaction*)NULL, &oact); 541 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 542 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 543 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) { 544 return true; 545 } else { 546 return false; 547 } 548} 549 550void os::Bsd::signal_sets_init() { 551 // Should also have an assertion stating we are still single-threaded. 552 assert(!signal_sets_initialized, "Already initialized"); 553 // Fill in signals that are necessarily unblocked for all threads in 554 // the VM. Currently, we unblock the following signals: 555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 556 // by -Xrs (=ReduceSignalUsage)); 557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 559 // the dispositions or masks wrt these signals. 560 // Programs embedding the VM that want to use the above signals for their 561 // own purposes must, at this time, use the "-Xrs" option to prevent 562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 563 // (See bug 4345157, and other related bugs). 564 // In reality, though, unblocking these signals is really a nop, since 565 // these signals are not blocked by default. 566 sigemptyset(&unblocked_sigs); 567 sigemptyset(&allowdebug_blocked_sigs); 568 sigaddset(&unblocked_sigs, SIGILL); 569 sigaddset(&unblocked_sigs, SIGSEGV); 570 sigaddset(&unblocked_sigs, SIGBUS); 571 sigaddset(&unblocked_sigs, SIGFPE); 572 sigaddset(&unblocked_sigs, SR_signum); 573 574 if (!ReduceSignalUsage) { 575 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 576 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 577 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 578 } 579 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 580 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 581 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 582 } 583 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 584 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 585 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 586 } 587 } 588 // Fill in signals that are blocked by all but the VM thread. 589 sigemptyset(&vm_sigs); 590 if (!ReduceSignalUsage) { 591 sigaddset(&vm_sigs, BREAK_SIGNAL); 592 } 593 debug_only(signal_sets_initialized = true); 594 595} 596 597// These are signals that are unblocked while a thread is running Java. 598// (For some reason, they get blocked by default.) 599sigset_t* os::Bsd::unblocked_signals() { 600 assert(signal_sets_initialized, "Not initialized"); 601 return &unblocked_sigs; 602} 603 604// These are the signals that are blocked while a (non-VM) thread is 605// running Java. Only the VM thread handles these signals. 606sigset_t* os::Bsd::vm_signals() { 607 assert(signal_sets_initialized, "Not initialized"); 608 return &vm_sigs; 609} 610 611// These are signals that are blocked during cond_wait to allow debugger in 612sigset_t* os::Bsd::allowdebug_blocked_signals() { 613 assert(signal_sets_initialized, "Not initialized"); 614 return &allowdebug_blocked_sigs; 615} 616 617void os::Bsd::hotspot_sigmask(Thread* thread) { 618 619 //Save caller's signal mask before setting VM signal mask 620 sigset_t caller_sigmask; 621 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 622 623 OSThread* osthread = thread->osthread(); 624 osthread->set_caller_sigmask(caller_sigmask); 625 626 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 627 628 if (!ReduceSignalUsage) { 629 if (thread->is_VM_thread()) { 630 // Only the VM thread handles BREAK_SIGNAL ... 631 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 632 } else { 633 // ... all other threads block BREAK_SIGNAL 634 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 635 } 636 } 637} 638 639 640////////////////////////////////////////////////////////////////////////////// 641// create new thread 642 643#ifdef __APPLE__ 644// library handle for calling objc_registerThreadWithCollector() 645// without static linking to the libobjc library 646 #define OBJC_LIB "/usr/lib/libobjc.dylib" 647 #define OBJC_GCREGISTER "objc_registerThreadWithCollector" 648typedef void (*objc_registerThreadWithCollector_t)(); 649extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 650objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 651#endif 652 653#ifdef __APPLE__ 654static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 655 // Additional thread_id used to correlate threads in SA 656 thread_identifier_info_data_t m_ident_info; 657 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 658 659 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 660 (thread_info_t) &m_ident_info, &count); 661 662 return m_ident_info.thread_id; 663} 664#endif 665 666// Thread start routine for all newly created threads 667static void *java_start(Thread *thread) { 668 // Try to randomize the cache line index of hot stack frames. 669 // This helps when threads of the same stack traces evict each other's 670 // cache lines. The threads can be either from the same JVM instance, or 671 // from different JVM instances. The benefit is especially true for 672 // processors with hyperthreading technology. 673 static int counter = 0; 674 int pid = os::current_process_id(); 675 alloca(((pid ^ counter++) & 7) * 128); 676 677 thread->initialize_thread_current(); 678 679 OSThread* osthread = thread->osthread(); 680 Monitor* sync = osthread->startThread_lock(); 681 682 osthread->set_thread_id(os::Bsd::gettid()); 683 684#ifdef __APPLE__ 685 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 686 guarantee(unique_thread_id != 0, "unique thread id was not found"); 687 osthread->set_unique_thread_id(unique_thread_id); 688#endif 689 // initialize signal mask for this thread 690 os::Bsd::hotspot_sigmask(thread); 691 692 // initialize floating point control register 693 os::Bsd::init_thread_fpu_state(); 694 695#ifdef __APPLE__ 696 // register thread with objc gc 697 if (objc_registerThreadWithCollectorFunction != NULL) { 698 objc_registerThreadWithCollectorFunction(); 699 } 700#endif 701 702 // handshaking with parent thread 703 { 704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 705 706 // notify parent thread 707 osthread->set_state(INITIALIZED); 708 sync->notify_all(); 709 710 // wait until os::start_thread() 711 while (osthread->get_state() == INITIALIZED) { 712 sync->wait(Mutex::_no_safepoint_check_flag); 713 } 714 } 715 716 // call one more level start routine 717 thread->run(); 718 719 return 0; 720} 721 722bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 723 assert(thread->osthread() == NULL, "caller responsible"); 724 725 // Allocate the OSThread object 726 OSThread* osthread = new OSThread(NULL, NULL); 727 if (osthread == NULL) { 728 return false; 729 } 730 731 // set the correct thread state 732 osthread->set_thread_type(thr_type); 733 734 // Initial state is ALLOCATED but not INITIALIZED 735 osthread->set_state(ALLOCATED); 736 737 thread->set_osthread(osthread); 738 739 // init thread attributes 740 pthread_attr_t attr; 741 pthread_attr_init(&attr); 742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 743 744 // calculate stack size if it's not specified by caller 745 if (stack_size == 0) { 746 stack_size = os::Bsd::default_stack_size(thr_type); 747 748 switch (thr_type) { 749 case os::java_thread: 750 // Java threads use ThreadStackSize which default value can be 751 // changed with the flag -Xss 752 assert(JavaThread::stack_size_at_create() > 0, "this should be set"); 753 stack_size = JavaThread::stack_size_at_create(); 754 break; 755 case os::compiler_thread: 756 if (CompilerThreadStackSize > 0) { 757 stack_size = (size_t)(CompilerThreadStackSize * K); 758 break; 759 } // else fall through: 760 // use VMThreadStackSize if CompilerThreadStackSize is not defined 761 case os::vm_thread: 762 case os::pgc_thread: 763 case os::cgc_thread: 764 case os::watcher_thread: 765 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 766 break; 767 } 768 } 769 770 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 771 pthread_attr_setstacksize(&attr, stack_size); 772 773 ThreadState state; 774 775 { 776 pthread_t tid; 777 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 778 779 pthread_attr_destroy(&attr); 780 781 if (ret != 0) { 782 if (PrintMiscellaneous && (Verbose || WizardMode)) { 783 perror("pthread_create()"); 784 } 785 // Need to clean up stuff we've allocated so far 786 thread->set_osthread(NULL); 787 delete osthread; 788 return false; 789 } 790 791 // Store pthread info into the OSThread 792 osthread->set_pthread_id(tid); 793 794 // Wait until child thread is either initialized or aborted 795 { 796 Monitor* sync_with_child = osthread->startThread_lock(); 797 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 798 while ((state = osthread->get_state()) == ALLOCATED) { 799 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 800 } 801 } 802 803 } 804 805 // Aborted due to thread limit being reached 806 if (state == ZOMBIE) { 807 thread->set_osthread(NULL); 808 delete osthread; 809 return false; 810 } 811 812 // The thread is returned suspended (in state INITIALIZED), 813 // and is started higher up in the call chain 814 assert(state == INITIALIZED, "race condition"); 815 return true; 816} 817 818///////////////////////////////////////////////////////////////////////////// 819// attach existing thread 820 821// bootstrap the main thread 822bool os::create_main_thread(JavaThread* thread) { 823 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 824 return create_attached_thread(thread); 825} 826 827bool os::create_attached_thread(JavaThread* thread) { 828#ifdef ASSERT 829 thread->verify_not_published(); 830#endif 831 832 // Allocate the OSThread object 833 OSThread* osthread = new OSThread(NULL, NULL); 834 835 if (osthread == NULL) { 836 return false; 837 } 838 839 osthread->set_thread_id(os::Bsd::gettid()); 840 841 // Store pthread info into the OSThread 842#ifdef __APPLE__ 843 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 844 guarantee(unique_thread_id != 0, "just checking"); 845 osthread->set_unique_thread_id(unique_thread_id); 846#endif 847 osthread->set_pthread_id(::pthread_self()); 848 849 // initialize floating point control register 850 os::Bsd::init_thread_fpu_state(); 851 852 // Initial thread state is RUNNABLE 853 osthread->set_state(RUNNABLE); 854 855 thread->set_osthread(osthread); 856 857 // initialize signal mask for this thread 858 // and save the caller's signal mask 859 os::Bsd::hotspot_sigmask(thread); 860 861 return true; 862} 863 864void os::pd_start_thread(Thread* thread) { 865 OSThread * osthread = thread->osthread(); 866 assert(osthread->get_state() != INITIALIZED, "just checking"); 867 Monitor* sync_with_child = osthread->startThread_lock(); 868 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 869 sync_with_child->notify(); 870} 871 872// Free Bsd resources related to the OSThread 873void os::free_thread(OSThread* osthread) { 874 assert(osthread != NULL, "osthread not set"); 875 876 if (Thread::current()->osthread() == osthread) { 877 // Restore caller's signal mask 878 sigset_t sigmask = osthread->caller_sigmask(); 879 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 880 } 881 882 delete osthread; 883} 884 885//////////////////////////////////////////////////////////////////////////////// 886// time support 887 888// Time since start-up in seconds to a fine granularity. 889// Used by VMSelfDestructTimer and the MemProfiler. 890double os::elapsedTime() { 891 892 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 893} 894 895jlong os::elapsed_counter() { 896 return javaTimeNanos() - initial_time_count; 897} 898 899jlong os::elapsed_frequency() { 900 return NANOSECS_PER_SEC; // nanosecond resolution 901} 902 903bool os::supports_vtime() { return true; } 904bool os::enable_vtime() { return false; } 905bool os::vtime_enabled() { return false; } 906 907double os::elapsedVTime() { 908 // better than nothing, but not much 909 return elapsedTime(); 910} 911 912jlong os::javaTimeMillis() { 913 timeval time; 914 int status = gettimeofday(&time, NULL); 915 assert(status != -1, "bsd error"); 916 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 917} 918 919void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) { 920 timeval time; 921 int status = gettimeofday(&time, NULL); 922 assert(status != -1, "bsd error"); 923 seconds = jlong(time.tv_sec); 924 nanos = jlong(time.tv_usec) * 1000; 925} 926 927#ifndef __APPLE__ 928 #ifndef CLOCK_MONOTONIC 929 #define CLOCK_MONOTONIC (1) 930 #endif 931#endif 932 933#ifdef __APPLE__ 934void os::Bsd::clock_init() { 935 mach_timebase_info(&_timebase_info); 936} 937#else 938void os::Bsd::clock_init() { 939 struct timespec res; 940 struct timespec tp; 941 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 942 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 943 // yes, monotonic clock is supported 944 _clock_gettime = ::clock_gettime; 945 } 946} 947#endif 948 949 950 951#ifdef __APPLE__ 952 953jlong os::javaTimeNanos() { 954 const uint64_t tm = mach_absolute_time(); 955 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 956 const uint64_t prev = Bsd::_max_abstime; 957 if (now <= prev) { 958 return prev; // same or retrograde time; 959 } 960 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 961 assert(obsv >= prev, "invariant"); // Monotonicity 962 // If the CAS succeeded then we're done and return "now". 963 // If the CAS failed and the observed value "obsv" is >= now then 964 // we should return "obsv". If the CAS failed and now > obsv > prv then 965 // some other thread raced this thread and installed a new value, in which case 966 // we could either (a) retry the entire operation, (b) retry trying to install now 967 // or (c) just return obsv. We use (c). No loop is required although in some cases 968 // we might discard a higher "now" value in deference to a slightly lower but freshly 969 // installed obsv value. That's entirely benign -- it admits no new orderings compared 970 // to (a) or (b) -- and greatly reduces coherence traffic. 971 // We might also condition (c) on the magnitude of the delta between obsv and now. 972 // Avoiding excessive CAS operations to hot RW locations is critical. 973 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 974 return (prev == obsv) ? now : obsv; 975} 976 977#else // __APPLE__ 978 979jlong os::javaTimeNanos() { 980 if (os::supports_monotonic_clock()) { 981 struct timespec tp; 982 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 983 assert(status == 0, "gettime error"); 984 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 985 return result; 986 } else { 987 timeval time; 988 int status = gettimeofday(&time, NULL); 989 assert(status != -1, "bsd error"); 990 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 991 return 1000 * usecs; 992 } 993} 994 995#endif // __APPLE__ 996 997void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 998 if (os::supports_monotonic_clock()) { 999 info_ptr->max_value = ALL_64_BITS; 1000 1001 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1002 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1003 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1004 } else { 1005 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1006 info_ptr->max_value = ALL_64_BITS; 1007 1008 // gettimeofday is a real time clock so it skips 1009 info_ptr->may_skip_backward = true; 1010 info_ptr->may_skip_forward = true; 1011 } 1012 1013 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1014} 1015 1016// Return the real, user, and system times in seconds from an 1017// arbitrary fixed point in the past. 1018bool os::getTimesSecs(double* process_real_time, 1019 double* process_user_time, 1020 double* process_system_time) { 1021 struct tms ticks; 1022 clock_t real_ticks = times(&ticks); 1023 1024 if (real_ticks == (clock_t) (-1)) { 1025 return false; 1026 } else { 1027 double ticks_per_second = (double) clock_tics_per_sec; 1028 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1029 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1030 *process_real_time = ((double) real_ticks) / ticks_per_second; 1031 1032 return true; 1033 } 1034} 1035 1036 1037char * os::local_time_string(char *buf, size_t buflen) { 1038 struct tm t; 1039 time_t long_time; 1040 time(&long_time); 1041 localtime_r(&long_time, &t); 1042 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1043 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1044 t.tm_hour, t.tm_min, t.tm_sec); 1045 return buf; 1046} 1047 1048struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1049 return localtime_r(clock, res); 1050} 1051 1052//////////////////////////////////////////////////////////////////////////////// 1053// runtime exit support 1054 1055// Note: os::shutdown() might be called very early during initialization, or 1056// called from signal handler. Before adding something to os::shutdown(), make 1057// sure it is async-safe and can handle partially initialized VM. 1058void os::shutdown() { 1059 1060 // allow PerfMemory to attempt cleanup of any persistent resources 1061 perfMemory_exit(); 1062 1063 // needs to remove object in file system 1064 AttachListener::abort(); 1065 1066 // flush buffered output, finish log files 1067 ostream_abort(); 1068 1069 // Check for abort hook 1070 abort_hook_t abort_hook = Arguments::abort_hook(); 1071 if (abort_hook != NULL) { 1072 abort_hook(); 1073 } 1074 1075} 1076 1077// Note: os::abort() might be called very early during initialization, or 1078// called from signal handler. Before adding something to os::abort(), make 1079// sure it is async-safe and can handle partially initialized VM. 1080void os::abort(bool dump_core, void* siginfo, void* context) { 1081 os::shutdown(); 1082 if (dump_core) { 1083#ifndef PRODUCT 1084 fdStream out(defaultStream::output_fd()); 1085 out.print_raw("Current thread is "); 1086 char buf[16]; 1087 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1088 out.print_raw_cr(buf); 1089 out.print_raw_cr("Dumping core ..."); 1090#endif 1091 ::abort(); // dump core 1092 } 1093 1094 ::exit(1); 1095} 1096 1097// Die immediately, no exit hook, no abort hook, no cleanup. 1098void os::die() { 1099 // _exit() on BsdThreads only kills current thread 1100 ::abort(); 1101} 1102 1103// This method is a copy of JDK's sysGetLastErrorString 1104// from src/solaris/hpi/src/system_md.c 1105 1106size_t os::lasterror(char *buf, size_t len) { 1107 if (errno == 0) return 0; 1108 1109 const char *s = ::strerror(errno); 1110 size_t n = ::strlen(s); 1111 if (n >= len) { 1112 n = len - 1; 1113 } 1114 ::strncpy(buf, s, n); 1115 buf[n] = '\0'; 1116 return n; 1117} 1118 1119// Information of current thread in variety of formats 1120pid_t os::Bsd::gettid() { 1121 int retval = -1; 1122 1123#ifdef __APPLE__ //XNU kernel 1124 // despite the fact mach port is actually not a thread id use it 1125 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1126 retval = ::pthread_mach_thread_np(::pthread_self()); 1127 guarantee(retval != 0, "just checking"); 1128 return retval; 1129 1130#else 1131 #ifdef __FreeBSD__ 1132 retval = syscall(SYS_thr_self); 1133 #else 1134 #ifdef __OpenBSD__ 1135 retval = syscall(SYS_getthrid); 1136 #else 1137 #ifdef __NetBSD__ 1138 retval = (pid_t) syscall(SYS__lwp_self); 1139 #endif 1140 #endif 1141 #endif 1142#endif 1143 1144 if (retval == -1) { 1145 return getpid(); 1146 } 1147} 1148 1149intx os::current_thread_id() { 1150#ifdef __APPLE__ 1151 return (intx)::pthread_mach_thread_np(::pthread_self()); 1152#else 1153 return (intx)::pthread_self(); 1154#endif 1155} 1156 1157int os::current_process_id() { 1158 1159 // Under the old bsd thread library, bsd gives each thread 1160 // its own process id. Because of this each thread will return 1161 // a different pid if this method were to return the result 1162 // of getpid(2). Bsd provides no api that returns the pid 1163 // of the launcher thread for the vm. This implementation 1164 // returns a unique pid, the pid of the launcher thread 1165 // that starts the vm 'process'. 1166 1167 // Under the NPTL, getpid() returns the same pid as the 1168 // launcher thread rather than a unique pid per thread. 1169 // Use gettid() if you want the old pre NPTL behaviour. 1170 1171 // if you are looking for the result of a call to getpid() that 1172 // returns a unique pid for the calling thread, then look at the 1173 // OSThread::thread_id() method in osThread_bsd.hpp file 1174 1175 return (int)(_initial_pid ? _initial_pid : getpid()); 1176} 1177 1178// DLL functions 1179 1180#define JNI_LIB_PREFIX "lib" 1181#ifdef __APPLE__ 1182 #define JNI_LIB_SUFFIX ".dylib" 1183#else 1184 #define JNI_LIB_SUFFIX ".so" 1185#endif 1186 1187const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1188 1189// This must be hard coded because it's the system's temporary 1190// directory not the java application's temp directory, ala java.io.tmpdir. 1191#ifdef __APPLE__ 1192// macosx has a secure per-user temporary directory 1193char temp_path_storage[PATH_MAX]; 1194const char* os::get_temp_directory() { 1195 static char *temp_path = NULL; 1196 if (temp_path == NULL) { 1197 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1198 if (pathSize == 0 || pathSize > PATH_MAX) { 1199 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1200 } 1201 temp_path = temp_path_storage; 1202 } 1203 return temp_path; 1204} 1205#else // __APPLE__ 1206const char* os::get_temp_directory() { return "/tmp"; } 1207#endif // __APPLE__ 1208 1209static bool file_exists(const char* filename) { 1210 struct stat statbuf; 1211 if (filename == NULL || strlen(filename) == 0) { 1212 return false; 1213 } 1214 return os::stat(filename, &statbuf) == 0; 1215} 1216 1217bool os::dll_build_name(char* buffer, size_t buflen, 1218 const char* pname, const char* fname) { 1219 bool retval = false; 1220 // Copied from libhpi 1221 const size_t pnamelen = pname ? strlen(pname) : 0; 1222 1223 // Return error on buffer overflow. 1224 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1225 return retval; 1226 } 1227 1228 if (pnamelen == 0) { 1229 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1230 retval = true; 1231 } else if (strchr(pname, *os::path_separator()) != NULL) { 1232 int n; 1233 char** pelements = split_path(pname, &n); 1234 if (pelements == NULL) { 1235 return false; 1236 } 1237 for (int i = 0; i < n; i++) { 1238 // Really shouldn't be NULL, but check can't hurt 1239 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1240 continue; // skip the empty path values 1241 } 1242 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1243 pelements[i], fname); 1244 if (file_exists(buffer)) { 1245 retval = true; 1246 break; 1247 } 1248 } 1249 // release the storage 1250 for (int i = 0; i < n; i++) { 1251 if (pelements[i] != NULL) { 1252 FREE_C_HEAP_ARRAY(char, pelements[i]); 1253 } 1254 } 1255 if (pelements != NULL) { 1256 FREE_C_HEAP_ARRAY(char*, pelements); 1257 } 1258 } else { 1259 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1260 retval = true; 1261 } 1262 return retval; 1263} 1264 1265// check if addr is inside libjvm.so 1266bool os::address_is_in_vm(address addr) { 1267 static address libjvm_base_addr; 1268 Dl_info dlinfo; 1269 1270 if (libjvm_base_addr == NULL) { 1271 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1272 libjvm_base_addr = (address)dlinfo.dli_fbase; 1273 } 1274 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1275 } 1276 1277 if (dladdr((void *)addr, &dlinfo) != 0) { 1278 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1279 } 1280 1281 return false; 1282} 1283 1284 1285#define MACH_MAXSYMLEN 256 1286 1287bool os::dll_address_to_function_name(address addr, char *buf, 1288 int buflen, int *offset, 1289 bool demangle) { 1290 // buf is not optional, but offset is optional 1291 assert(buf != NULL, "sanity check"); 1292 1293 Dl_info dlinfo; 1294 char localbuf[MACH_MAXSYMLEN]; 1295 1296 if (dladdr((void*)addr, &dlinfo) != 0) { 1297 // see if we have a matching symbol 1298 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1299 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) { 1300 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1301 } 1302 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1303 return true; 1304 } 1305 // no matching symbol so try for just file info 1306 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1307 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1308 buf, buflen, offset, dlinfo.dli_fname, demangle)) { 1309 return true; 1310 } 1311 } 1312 1313 // Handle non-dynamic manually: 1314 if (dlinfo.dli_fbase != NULL && 1315 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1316 dlinfo.dli_fbase)) { 1317 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) { 1318 jio_snprintf(buf, buflen, "%s", localbuf); 1319 } 1320 return true; 1321 } 1322 } 1323 buf[0] = '\0'; 1324 if (offset != NULL) *offset = -1; 1325 return false; 1326} 1327 1328// ported from solaris version 1329bool os::dll_address_to_library_name(address addr, char* buf, 1330 int buflen, int* offset) { 1331 // buf is not optional, but offset is optional 1332 assert(buf != NULL, "sanity check"); 1333 1334 Dl_info dlinfo; 1335 1336 if (dladdr((void*)addr, &dlinfo) != 0) { 1337 if (dlinfo.dli_fname != NULL) { 1338 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1339 } 1340 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1341 *offset = addr - (address)dlinfo.dli_fbase; 1342 } 1343 return true; 1344 } 1345 1346 buf[0] = '\0'; 1347 if (offset) *offset = -1; 1348 return false; 1349} 1350 1351// Loads .dll/.so and 1352// in case of error it checks if .dll/.so was built for the 1353// same architecture as Hotspot is running on 1354 1355#ifdef __APPLE__ 1356void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1357#ifdef STATIC_BUILD 1358 return os::get_default_process_handle(); 1359#else 1360 void * result= ::dlopen(filename, RTLD_LAZY); 1361 if (result != NULL) { 1362 // Successful loading 1363 return result; 1364 } 1365 1366 // Read system error message into ebuf 1367 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1368 ebuf[ebuflen-1]='\0'; 1369 1370 return NULL; 1371#endif // STATIC_BUILD 1372} 1373#else 1374void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1375#ifdef STATIC_BUILD 1376 return os::get_default_process_handle(); 1377#else 1378 void * result= ::dlopen(filename, RTLD_LAZY); 1379 if (result != NULL) { 1380 // Successful loading 1381 return result; 1382 } 1383 1384 Elf32_Ehdr elf_head; 1385 1386 // Read system error message into ebuf 1387 // It may or may not be overwritten below 1388 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1389 ebuf[ebuflen-1]='\0'; 1390 int diag_msg_max_length=ebuflen-strlen(ebuf); 1391 char* diag_msg_buf=ebuf+strlen(ebuf); 1392 1393 if (diag_msg_max_length==0) { 1394 // No more space in ebuf for additional diagnostics message 1395 return NULL; 1396 } 1397 1398 1399 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1400 1401 if (file_descriptor < 0) { 1402 // Can't open library, report dlerror() message 1403 return NULL; 1404 } 1405 1406 bool failed_to_read_elf_head= 1407 (sizeof(elf_head)!= 1408 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1409 1410 ::close(file_descriptor); 1411 if (failed_to_read_elf_head) { 1412 // file i/o error - report dlerror() msg 1413 return NULL; 1414 } 1415 1416 typedef struct { 1417 Elf32_Half code; // Actual value as defined in elf.h 1418 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1419 char elf_class; // 32 or 64 bit 1420 char endianess; // MSB or LSB 1421 char* name; // String representation 1422 } arch_t; 1423 1424 #ifndef EM_486 1425 #define EM_486 6 /* Intel 80486 */ 1426 #endif 1427 1428 #ifndef EM_MIPS_RS3_LE 1429 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1430 #endif 1431 1432 #ifndef EM_PPC64 1433 #define EM_PPC64 21 /* PowerPC64 */ 1434 #endif 1435 1436 #ifndef EM_S390 1437 #define EM_S390 22 /* IBM System/390 */ 1438 #endif 1439 1440 #ifndef EM_IA_64 1441 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1442 #endif 1443 1444 #ifndef EM_X86_64 1445 #define EM_X86_64 62 /* AMD x86-64 */ 1446 #endif 1447 1448 static const arch_t arch_array[]={ 1449 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1450 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1451 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1452 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1453 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1454 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1455 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1456 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1457 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1458 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1459 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1460 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1461 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1462 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1463 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1464 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1465 }; 1466 1467 #if (defined IA32) 1468 static Elf32_Half running_arch_code=EM_386; 1469 #elif (defined AMD64) 1470 static Elf32_Half running_arch_code=EM_X86_64; 1471 #elif (defined IA64) 1472 static Elf32_Half running_arch_code=EM_IA_64; 1473 #elif (defined __sparc) && (defined _LP64) 1474 static Elf32_Half running_arch_code=EM_SPARCV9; 1475 #elif (defined __sparc) && (!defined _LP64) 1476 static Elf32_Half running_arch_code=EM_SPARC; 1477 #elif (defined __powerpc64__) 1478 static Elf32_Half running_arch_code=EM_PPC64; 1479 #elif (defined __powerpc__) 1480 static Elf32_Half running_arch_code=EM_PPC; 1481 #elif (defined ARM) 1482 static Elf32_Half running_arch_code=EM_ARM; 1483 #elif (defined S390) 1484 static Elf32_Half running_arch_code=EM_S390; 1485 #elif (defined ALPHA) 1486 static Elf32_Half running_arch_code=EM_ALPHA; 1487 #elif (defined MIPSEL) 1488 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1489 #elif (defined PARISC) 1490 static Elf32_Half running_arch_code=EM_PARISC; 1491 #elif (defined MIPS) 1492 static Elf32_Half running_arch_code=EM_MIPS; 1493 #elif (defined M68K) 1494 static Elf32_Half running_arch_code=EM_68K; 1495 #else 1496 #error Method os::dll_load requires that one of following is defined:\ 1497 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1498 #endif 1499 1500 // Identify compatability class for VM's architecture and library's architecture 1501 // Obtain string descriptions for architectures 1502 1503 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1504 int running_arch_index=-1; 1505 1506 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1507 if (running_arch_code == arch_array[i].code) { 1508 running_arch_index = i; 1509 } 1510 if (lib_arch.code == arch_array[i].code) { 1511 lib_arch.compat_class = arch_array[i].compat_class; 1512 lib_arch.name = arch_array[i].name; 1513 } 1514 } 1515 1516 assert(running_arch_index != -1, 1517 "Didn't find running architecture code (running_arch_code) in arch_array"); 1518 if (running_arch_index == -1) { 1519 // Even though running architecture detection failed 1520 // we may still continue with reporting dlerror() message 1521 return NULL; 1522 } 1523 1524 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1525 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1526 return NULL; 1527 } 1528 1529#ifndef S390 1530 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1531 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1532 return NULL; 1533 } 1534#endif // !S390 1535 1536 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1537 if (lib_arch.name!=NULL) { 1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1539 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1540 lib_arch.name, arch_array[running_arch_index].name); 1541 } else { 1542 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1543 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1544 lib_arch.code, 1545 arch_array[running_arch_index].name); 1546 } 1547 } 1548 1549 return NULL; 1550#endif // STATIC_BUILD 1551} 1552#endif // !__APPLE__ 1553 1554void* os::get_default_process_handle() { 1555#ifdef __APPLE__ 1556 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1557 // to avoid finding unexpected symbols on second (or later) 1558 // loads of a library. 1559 return (void*)::dlopen(NULL, RTLD_FIRST); 1560#else 1561 return (void*)::dlopen(NULL, RTLD_LAZY); 1562#endif 1563} 1564 1565// XXX: Do we need a lock around this as per Linux? 1566void* os::dll_lookup(void* handle, const char* name) { 1567 return dlsym(handle, name); 1568} 1569 1570int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1571 outputStream * out = (outputStream *) param; 1572 out->print_cr(PTR_FORMAT " \t%s", base_address, name); 1573 return 0; 1574} 1575 1576void os::print_dll_info(outputStream *st) { 1577 st->print_cr("Dynamic libraries:"); 1578 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1579 st->print_cr("Error: Cannot print dynamic libraries."); 1580 } 1581} 1582 1583int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1584#ifdef RTLD_DI_LINKMAP 1585 Dl_info dli; 1586 void *handle; 1587 Link_map *map; 1588 Link_map *p; 1589 1590 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1591 dli.dli_fname == NULL) { 1592 return 1; 1593 } 1594 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1595 if (handle == NULL) { 1596 return 1; 1597 } 1598 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1599 if (map == NULL) { 1600 dlclose(handle); 1601 return 1; 1602 } 1603 1604 while (map->l_prev != NULL) 1605 map = map->l_prev; 1606 1607 while (map != NULL) { 1608 // Value for top_address is returned as 0 since we don't have any information about module size 1609 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1610 dlclose(handle); 1611 return 1; 1612 } 1613 map = map->l_next; 1614 } 1615 1616 dlclose(handle); 1617#elif defined(__APPLE__) 1618 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1619 // Value for top_address is returned as 0 since we don't have any information about module size 1620 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1621 return 1; 1622 } 1623 } 1624 return 0; 1625#else 1626 return 1; 1627#endif 1628} 1629 1630void os::get_summary_os_info(char* buf, size_t buflen) { 1631 // These buffers are small because we want this to be brief 1632 // and not use a lot of stack while generating the hs_err file. 1633 char os[100]; 1634 size_t size = sizeof(os); 1635 int mib_kern[] = { CTL_KERN, KERN_OSTYPE }; 1636 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) { 1637#ifdef __APPLE__ 1638 strncpy(os, "Darwin", sizeof(os)); 1639#elif __OpenBSD__ 1640 strncpy(os, "OpenBSD", sizeof(os)); 1641#else 1642 strncpy(os, "BSD", sizeof(os)); 1643#endif 1644 } 1645 1646 char release[100]; 1647 size = sizeof(release); 1648 int mib_release[] = { CTL_KERN, KERN_OSRELEASE }; 1649 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) { 1650 // if error, leave blank 1651 strncpy(release, "", sizeof(release)); 1652 } 1653 snprintf(buf, buflen, "%s %s", os, release); 1654} 1655 1656void os::print_os_info_brief(outputStream* st) { 1657 os::Posix::print_uname_info(st); 1658} 1659 1660void os::print_os_info(outputStream* st) { 1661 st->print("OS:"); 1662 1663 os::Posix::print_uname_info(st); 1664 1665 os::Posix::print_rlimit_info(st); 1666 1667 os::Posix::print_load_average(st); 1668} 1669 1670void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) { 1671 // Nothing to do for now. 1672} 1673 1674void os::get_summary_cpu_info(char* buf, size_t buflen) { 1675 unsigned int mhz; 1676 size_t size = sizeof(mhz); 1677 int mib[] = { CTL_HW, HW_CPU_FREQ }; 1678 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) { 1679 mhz = 1; // looks like an error but can be divided by 1680 } else { 1681 mhz /= 1000000; // reported in millions 1682 } 1683 1684 char model[100]; 1685 size = sizeof(model); 1686 int mib_model[] = { CTL_HW, HW_MODEL }; 1687 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) { 1688 strncpy(model, cpu_arch, sizeof(model)); 1689 } 1690 1691 char machine[100]; 1692 size = sizeof(machine); 1693 int mib_machine[] = { CTL_HW, HW_MACHINE }; 1694 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) { 1695 strncpy(machine, "", sizeof(machine)); 1696 } 1697 1698 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz); 1699} 1700 1701void os::print_memory_info(outputStream* st) { 1702 1703 st->print("Memory:"); 1704 st->print(" %dk page", os::vm_page_size()>>10); 1705 1706 st->print(", physical " UINT64_FORMAT "k", 1707 os::physical_memory() >> 10); 1708 st->print("(" UINT64_FORMAT "k free)", 1709 os::available_memory() >> 10); 1710 st->cr(); 1711} 1712 1713void os::print_siginfo(outputStream* st, void* siginfo) { 1714 const siginfo_t* si = (const siginfo_t*)siginfo; 1715 1716 os::Posix::print_siginfo_brief(st, si); 1717 1718 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1719 UseSharedSpaces) { 1720 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1721 if (mapinfo->is_in_shared_space(si->si_addr)) { 1722 st->print("\n\nError accessing class data sharing archive." \ 1723 " Mapped file inaccessible during execution, " \ 1724 " possible disk/network problem."); 1725 } 1726 } 1727 st->cr(); 1728} 1729 1730 1731static void print_signal_handler(outputStream* st, int sig, 1732 char* buf, size_t buflen); 1733 1734void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1735 st->print_cr("Signal Handlers:"); 1736 print_signal_handler(st, SIGSEGV, buf, buflen); 1737 print_signal_handler(st, SIGBUS , buf, buflen); 1738 print_signal_handler(st, SIGFPE , buf, buflen); 1739 print_signal_handler(st, SIGPIPE, buf, buflen); 1740 print_signal_handler(st, SIGXFSZ, buf, buflen); 1741 print_signal_handler(st, SIGILL , buf, buflen); 1742 print_signal_handler(st, SR_signum, buf, buflen); 1743 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1744 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1745 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1746 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1747} 1748 1749static char saved_jvm_path[MAXPATHLEN] = {0}; 1750 1751// Find the full path to the current module, libjvm 1752void os::jvm_path(char *buf, jint buflen) { 1753 // Error checking. 1754 if (buflen < MAXPATHLEN) { 1755 assert(false, "must use a large-enough buffer"); 1756 buf[0] = '\0'; 1757 return; 1758 } 1759 // Lazy resolve the path to current module. 1760 if (saved_jvm_path[0] != 0) { 1761 strcpy(buf, saved_jvm_path); 1762 return; 1763 } 1764 1765 char dli_fname[MAXPATHLEN]; 1766 bool ret = dll_address_to_library_name( 1767 CAST_FROM_FN_PTR(address, os::jvm_path), 1768 dli_fname, sizeof(dli_fname), NULL); 1769 assert(ret, "cannot locate libjvm"); 1770 char *rp = NULL; 1771 if (ret && dli_fname[0] != '\0') { 1772 rp = realpath(dli_fname, buf); 1773 } 1774 if (rp == NULL) { 1775 return; 1776 } 1777 1778 if (Arguments::sun_java_launcher_is_altjvm()) { 1779 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1780 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1781 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1782 // appears at the right place in the string, then assume we are 1783 // installed in a JDK and we're done. Otherwise, check for a 1784 // JAVA_HOME environment variable and construct a path to the JVM 1785 // being overridden. 1786 1787 const char *p = buf + strlen(buf) - 1; 1788 for (int count = 0; p > buf && count < 5; ++count) { 1789 for (--p; p > buf && *p != '/'; --p) 1790 /* empty */ ; 1791 } 1792 1793 if (strncmp(p, "/jre/lib/", 9) != 0) { 1794 // Look for JAVA_HOME in the environment. 1795 char* java_home_var = ::getenv("JAVA_HOME"); 1796 if (java_home_var != NULL && java_home_var[0] != 0) { 1797 char* jrelib_p; 1798 int len; 1799 1800 // Check the current module name "libjvm" 1801 p = strrchr(buf, '/'); 1802 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1803 1804 rp = realpath(java_home_var, buf); 1805 if (rp == NULL) { 1806 return; 1807 } 1808 1809 // determine if this is a legacy image or modules image 1810 // modules image doesn't have "jre" subdirectory 1811 len = strlen(buf); 1812 assert(len < buflen, "Ran out of buffer space"); 1813 jrelib_p = buf + len; 1814 1815 // Add the appropriate library subdir 1816 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1817 if (0 != access(buf, F_OK)) { 1818 snprintf(jrelib_p, buflen-len, "/lib"); 1819 } 1820 1821 // Add the appropriate client or server subdir 1822 len = strlen(buf); 1823 jrelib_p = buf + len; 1824 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1825 if (0 != access(buf, F_OK)) { 1826 snprintf(jrelib_p, buflen-len, "%s", ""); 1827 } 1828 1829 // If the path exists within JAVA_HOME, add the JVM library name 1830 // to complete the path to JVM being overridden. Otherwise fallback 1831 // to the path to the current library. 1832 if (0 == access(buf, F_OK)) { 1833 // Use current module name "libjvm" 1834 len = strlen(buf); 1835 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1836 } else { 1837 // Fall back to path of current library 1838 rp = realpath(dli_fname, buf); 1839 if (rp == NULL) { 1840 return; 1841 } 1842 } 1843 } 1844 } 1845 } 1846 1847 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1848 saved_jvm_path[MAXPATHLEN - 1] = '\0'; 1849} 1850 1851void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1852 // no prefix required, not even "_" 1853} 1854 1855void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1856 // no suffix required 1857} 1858 1859//////////////////////////////////////////////////////////////////////////////// 1860// sun.misc.Signal support 1861 1862static volatile jint sigint_count = 0; 1863 1864static void UserHandler(int sig, void *siginfo, void *context) { 1865 // 4511530 - sem_post is serialized and handled by the manager thread. When 1866 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1867 // don't want to flood the manager thread with sem_post requests. 1868 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) { 1869 return; 1870 } 1871 1872 // Ctrl-C is pressed during error reporting, likely because the error 1873 // handler fails to abort. Let VM die immediately. 1874 if (sig == SIGINT && is_error_reported()) { 1875 os::die(); 1876 } 1877 1878 os::signal_notify(sig); 1879} 1880 1881void* os::user_handler() { 1882 return CAST_FROM_FN_PTR(void*, UserHandler); 1883} 1884 1885extern "C" { 1886 typedef void (*sa_handler_t)(int); 1887 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1888} 1889 1890void* os::signal(int signal_number, void* handler) { 1891 struct sigaction sigAct, oldSigAct; 1892 1893 sigfillset(&(sigAct.sa_mask)); 1894 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1895 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1896 1897 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1898 // -1 means registration failed 1899 return (void *)-1; 1900 } 1901 1902 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1903} 1904 1905void os::signal_raise(int signal_number) { 1906 ::raise(signal_number); 1907} 1908 1909// The following code is moved from os.cpp for making this 1910// code platform specific, which it is by its very nature. 1911 1912// Will be modified when max signal is changed to be dynamic 1913int os::sigexitnum_pd() { 1914 return NSIG; 1915} 1916 1917// a counter for each possible signal value 1918static volatile jint pending_signals[NSIG+1] = { 0 }; 1919 1920// Bsd(POSIX) specific hand shaking semaphore. 1921#ifdef __APPLE__ 1922typedef semaphore_t os_semaphore_t; 1923 1924 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1925 #define SEM_WAIT(sem) semaphore_wait(sem) 1926 #define SEM_POST(sem) semaphore_signal(sem) 1927 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1928#else 1929typedef sem_t os_semaphore_t; 1930 1931 #define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1932 #define SEM_WAIT(sem) sem_wait(&sem) 1933 #define SEM_POST(sem) sem_post(&sem) 1934 #define SEM_DESTROY(sem) sem_destroy(&sem) 1935#endif 1936 1937#ifdef __APPLE__ 1938// OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used. 1939 1940static const char* sem_init_strerror(kern_return_t value) { 1941 switch (value) { 1942 case KERN_INVALID_ARGUMENT: return "Invalid argument"; 1943 case KERN_RESOURCE_SHORTAGE: return "Resource shortage"; 1944 default: return "Unknown"; 1945 } 1946} 1947 1948OSXSemaphore::OSXSemaphore(uint value) { 1949 kern_return_t ret = SEM_INIT(_semaphore, value); 1950 1951 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret)); 1952} 1953 1954OSXSemaphore::~OSXSemaphore() { 1955 SEM_DESTROY(_semaphore); 1956} 1957 1958void OSXSemaphore::signal(uint count) { 1959 for (uint i = 0; i < count; i++) { 1960 kern_return_t ret = SEM_POST(_semaphore); 1961 1962 assert(ret == KERN_SUCCESS, "Failed to signal semaphore"); 1963 } 1964} 1965 1966void OSXSemaphore::wait() { 1967 kern_return_t ret; 1968 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) { 1969 // Semaphore was interrupted. Retry. 1970 } 1971 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore"); 1972} 1973 1974jlong OSXSemaphore::currenttime() { 1975 struct timeval tv; 1976 gettimeofday(&tv, NULL); 1977 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1978} 1979 1980bool OSXSemaphore::trywait() { 1981 return timedwait(0, 0); 1982} 1983 1984bool OSXSemaphore::timedwait(unsigned int sec, int nsec) { 1985 kern_return_t kr = KERN_ABORTED; 1986 mach_timespec_t waitspec; 1987 waitspec.tv_sec = sec; 1988 waitspec.tv_nsec = nsec; 1989 1990 jlong starttime = currenttime(); 1991 1992 kr = semaphore_timedwait(_semaphore, waitspec); 1993 while (kr == KERN_ABORTED) { 1994 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 1995 1996 jlong current = currenttime(); 1997 jlong passedtime = current - starttime; 1998 1999 if (passedtime >= totalwait) { 2000 waitspec.tv_sec = 0; 2001 waitspec.tv_nsec = 0; 2002 } else { 2003 jlong waittime = totalwait - (current - starttime); 2004 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2005 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2006 } 2007 2008 kr = semaphore_timedwait(_semaphore, waitspec); 2009 } 2010 2011 return kr == KERN_SUCCESS; 2012} 2013 2014#else 2015// Use POSIX implementation of semaphores. 2016 2017struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) { 2018 struct timespec ts; 2019 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2020 2021 return ts; 2022} 2023 2024#endif // __APPLE__ 2025 2026static os_semaphore_t sig_sem; 2027 2028#ifdef __APPLE__ 2029static OSXSemaphore sr_semaphore; 2030#else 2031static PosixSemaphore sr_semaphore; 2032#endif 2033 2034void os::signal_init_pd() { 2035 // Initialize signal structures 2036 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2037 2038 // Initialize signal semaphore 2039 ::SEM_INIT(sig_sem, 0); 2040} 2041 2042void os::signal_notify(int sig) { 2043 Atomic::inc(&pending_signals[sig]); 2044 ::SEM_POST(sig_sem); 2045} 2046 2047static int check_pending_signals(bool wait) { 2048 Atomic::store(0, &sigint_count); 2049 for (;;) { 2050 for (int i = 0; i < NSIG + 1; i++) { 2051 jint n = pending_signals[i]; 2052 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2053 return i; 2054 } 2055 } 2056 if (!wait) { 2057 return -1; 2058 } 2059 JavaThread *thread = JavaThread::current(); 2060 ThreadBlockInVM tbivm(thread); 2061 2062 bool threadIsSuspended; 2063 do { 2064 thread->set_suspend_equivalent(); 2065 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2066 ::SEM_WAIT(sig_sem); 2067 2068 // were we externally suspended while we were waiting? 2069 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2070 if (threadIsSuspended) { 2071 // The semaphore has been incremented, but while we were waiting 2072 // another thread suspended us. We don't want to continue running 2073 // while suspended because that would surprise the thread that 2074 // suspended us. 2075 ::SEM_POST(sig_sem); 2076 2077 thread->java_suspend_self(); 2078 } 2079 } while (threadIsSuspended); 2080 } 2081} 2082 2083int os::signal_lookup() { 2084 return check_pending_signals(false); 2085} 2086 2087int os::signal_wait() { 2088 return check_pending_signals(true); 2089} 2090 2091//////////////////////////////////////////////////////////////////////////////// 2092// Virtual Memory 2093 2094int os::vm_page_size() { 2095 // Seems redundant as all get out 2096 assert(os::Bsd::page_size() != -1, "must call os::init"); 2097 return os::Bsd::page_size(); 2098} 2099 2100// Solaris allocates memory by pages. 2101int os::vm_allocation_granularity() { 2102 assert(os::Bsd::page_size() != -1, "must call os::init"); 2103 return os::Bsd::page_size(); 2104} 2105 2106// Rationale behind this function: 2107// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2108// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2109// samples for JITted code. Here we create private executable mapping over the code cache 2110// and then we can use standard (well, almost, as mapping can change) way to provide 2111// info for the reporting script by storing timestamp and location of symbol 2112void bsd_wrap_code(char* base, size_t size) { 2113 static volatile jint cnt = 0; 2114 2115 if (!UseOprofile) { 2116 return; 2117 } 2118 2119 char buf[PATH_MAX + 1]; 2120 int num = Atomic::add(1, &cnt); 2121 2122 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2123 os::get_temp_directory(), os::current_process_id(), num); 2124 unlink(buf); 2125 2126 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2127 2128 if (fd != -1) { 2129 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2130 if (rv != (off_t)-1) { 2131 if (::write(fd, "", 1) == 1) { 2132 mmap(base, size, 2133 PROT_READ|PROT_WRITE|PROT_EXEC, 2134 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2135 } 2136 } 2137 ::close(fd); 2138 unlink(buf); 2139 } 2140} 2141 2142static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2143 int err) { 2144 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2145 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2146 strerror(err), err); 2147} 2148 2149// NOTE: Bsd kernel does not really reserve the pages for us. 2150// All it does is to check if there are enough free pages 2151// left at the time of mmap(). This could be a potential 2152// problem. 2153bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2154 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2155#ifdef __OpenBSD__ 2156 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2157 if (::mprotect(addr, size, prot) == 0) { 2158 return true; 2159 } 2160#else 2161 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2162 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2163 if (res != (uintptr_t) MAP_FAILED) { 2164 return true; 2165 } 2166#endif 2167 2168 // Warn about any commit errors we see in non-product builds just 2169 // in case mmap() doesn't work as described on the man page. 2170 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2171 2172 return false; 2173} 2174 2175bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2176 bool exec) { 2177 // alignment_hint is ignored on this OS 2178 return pd_commit_memory(addr, size, exec); 2179} 2180 2181void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2182 const char* mesg) { 2183 assert(mesg != NULL, "mesg must be specified"); 2184 if (!pd_commit_memory(addr, size, exec)) { 2185 // add extra info in product mode for vm_exit_out_of_memory(): 2186 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2187 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg); 2188 } 2189} 2190 2191void os::pd_commit_memory_or_exit(char* addr, size_t size, 2192 size_t alignment_hint, bool exec, 2193 const char* mesg) { 2194 // alignment_hint is ignored on this OS 2195 pd_commit_memory_or_exit(addr, size, exec, mesg); 2196} 2197 2198void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2199} 2200 2201void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2202 ::madvise(addr, bytes, MADV_DONTNEED); 2203} 2204 2205void os::numa_make_global(char *addr, size_t bytes) { 2206} 2207 2208void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2209} 2210 2211bool os::numa_topology_changed() { return false; } 2212 2213size_t os::numa_get_groups_num() { 2214 return 1; 2215} 2216 2217int os::numa_get_group_id() { 2218 return 0; 2219} 2220 2221size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2222 if (size > 0) { 2223 ids[0] = 0; 2224 return 1; 2225 } 2226 return 0; 2227} 2228 2229bool os::get_page_info(char *start, page_info* info) { 2230 return false; 2231} 2232 2233char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2234 return end; 2235} 2236 2237 2238bool os::pd_uncommit_memory(char* addr, size_t size) { 2239#ifdef __OpenBSD__ 2240 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2241 return ::mprotect(addr, size, PROT_NONE) == 0; 2242#else 2243 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2244 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2245 return res != (uintptr_t) MAP_FAILED; 2246#endif 2247} 2248 2249bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2250 return os::commit_memory(addr, size, !ExecMem); 2251} 2252 2253// If this is a growable mapping, remove the guard pages entirely by 2254// munmap()ping them. If not, just call uncommit_memory(). 2255bool os::remove_stack_guard_pages(char* addr, size_t size) { 2256 return os::uncommit_memory(addr, size); 2257} 2258 2259// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2260// at 'requested_addr'. If there are existing memory mappings at the same 2261// location, however, they will be overwritten. If 'fixed' is false, 2262// 'requested_addr' is only treated as a hint, the return value may or 2263// may not start from the requested address. Unlike Bsd mmap(), this 2264// function returns NULL to indicate failure. 2265static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2266 char * addr; 2267 int flags; 2268 2269 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2270 if (fixed) { 2271 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2272 flags |= MAP_FIXED; 2273 } 2274 2275 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2276 // touch an uncommitted page. Otherwise, the read/write might 2277 // succeed if we have enough swap space to back the physical page. 2278 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2279 flags, -1, 0); 2280 2281 return addr == MAP_FAILED ? NULL : addr; 2282} 2283 2284static int anon_munmap(char * addr, size_t size) { 2285 return ::munmap(addr, size) == 0; 2286} 2287 2288char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2289 size_t alignment_hint) { 2290 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2291} 2292 2293bool os::pd_release_memory(char* addr, size_t size) { 2294 return anon_munmap(addr, size); 2295} 2296 2297static bool bsd_mprotect(char* addr, size_t size, int prot) { 2298 // Bsd wants the mprotect address argument to be page aligned. 2299 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2300 2301 // According to SUSv3, mprotect() should only be used with mappings 2302 // established by mmap(), and mmap() always maps whole pages. Unaligned 2303 // 'addr' likely indicates problem in the VM (e.g. trying to change 2304 // protection of malloc'ed or statically allocated memory). Check the 2305 // caller if you hit this assert. 2306 assert(addr == bottom, "sanity check"); 2307 2308 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2309 return ::mprotect(bottom, size, prot) == 0; 2310} 2311 2312// Set protections specified 2313bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2314 bool is_committed) { 2315 unsigned int p = 0; 2316 switch (prot) { 2317 case MEM_PROT_NONE: p = PROT_NONE; break; 2318 case MEM_PROT_READ: p = PROT_READ; break; 2319 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2320 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2321 default: 2322 ShouldNotReachHere(); 2323 } 2324 // is_committed is unused. 2325 return bsd_mprotect(addr, bytes, p); 2326} 2327 2328bool os::guard_memory(char* addr, size_t size) { 2329 return bsd_mprotect(addr, size, PROT_NONE); 2330} 2331 2332bool os::unguard_memory(char* addr, size_t size) { 2333 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2334} 2335 2336bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2337 return false; 2338} 2339 2340// Large page support 2341 2342static size_t _large_page_size = 0; 2343 2344void os::large_page_init() { 2345} 2346 2347 2348char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2349 fatal("This code is not used or maintained."); 2350 2351 // "exec" is passed in but not used. Creating the shared image for 2352 // the code cache doesn't have an SHM_X executable permission to check. 2353 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2354 2355 key_t key = IPC_PRIVATE; 2356 char *addr; 2357 2358 bool warn_on_failure = UseLargePages && 2359 (!FLAG_IS_DEFAULT(UseLargePages) || 2360 !FLAG_IS_DEFAULT(LargePageSizeInBytes)); 2361 2362 // Create a large shared memory region to attach to based on size. 2363 // Currently, size is the total size of the heap 2364 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2365 if (shmid == -1) { 2366 // Possible reasons for shmget failure: 2367 // 1. shmmax is too small for Java heap. 2368 // > check shmmax value: cat /proc/sys/kernel/shmmax 2369 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2370 // 2. not enough large page memory. 2371 // > check available large pages: cat /proc/meminfo 2372 // > increase amount of large pages: 2373 // echo new_value > /proc/sys/vm/nr_hugepages 2374 // Note 1: different Bsd may use different name for this property, 2375 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2376 // Note 2: it's possible there's enough physical memory available but 2377 // they are so fragmented after a long run that they can't 2378 // coalesce into large pages. Try to reserve large pages when 2379 // the system is still "fresh". 2380 if (warn_on_failure) { 2381 warning("Failed to reserve shared memory (errno = %d).", errno); 2382 } 2383 return NULL; 2384 } 2385 2386 // attach to the region 2387 addr = (char*)shmat(shmid, req_addr, 0); 2388 int err = errno; 2389 2390 // Remove shmid. If shmat() is successful, the actual shared memory segment 2391 // will be deleted when it's detached by shmdt() or when the process 2392 // terminates. If shmat() is not successful this will remove the shared 2393 // segment immediately. 2394 shmctl(shmid, IPC_RMID, NULL); 2395 2396 if ((intptr_t)addr == -1) { 2397 if (warn_on_failure) { 2398 warning("Failed to attach shared memory (errno = %d).", err); 2399 } 2400 return NULL; 2401 } 2402 2403 // The memory is committed 2404 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2405 2406 return addr; 2407} 2408 2409bool os::release_memory_special(char* base, size_t bytes) { 2410 if (MemTracker::tracking_level() > NMT_minimal) { 2411 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2412 // detaching the SHM segment will also delete it, see reserve_memory_special() 2413 int rslt = shmdt(base); 2414 if (rslt == 0) { 2415 tkr.record((address)base, bytes); 2416 return true; 2417 } else { 2418 return false; 2419 } 2420 } else { 2421 return shmdt(base) == 0; 2422 } 2423} 2424 2425size_t os::large_page_size() { 2426 return _large_page_size; 2427} 2428 2429// HugeTLBFS allows application to commit large page memory on demand; 2430// with SysV SHM the entire memory region must be allocated as shared 2431// memory. 2432bool os::can_commit_large_page_memory() { 2433 return UseHugeTLBFS; 2434} 2435 2436bool os::can_execute_large_page_memory() { 2437 return UseHugeTLBFS; 2438} 2439 2440// Reserve memory at an arbitrary address, only if that area is 2441// available (and not reserved for something else). 2442 2443char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2444 const int max_tries = 10; 2445 char* base[max_tries]; 2446 size_t size[max_tries]; 2447 const size_t gap = 0x000000; 2448 2449 // Assert only that the size is a multiple of the page size, since 2450 // that's all that mmap requires, and since that's all we really know 2451 // about at this low abstraction level. If we need higher alignment, 2452 // we can either pass an alignment to this method or verify alignment 2453 // in one of the methods further up the call chain. See bug 5044738. 2454 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2455 2456 // Repeatedly allocate blocks until the block is allocated at the 2457 // right spot. 2458 2459 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2460 // if kernel honors the hint then we can return immediately. 2461 char * addr = anon_mmap(requested_addr, bytes, false); 2462 if (addr == requested_addr) { 2463 return requested_addr; 2464 } 2465 2466 if (addr != NULL) { 2467 // mmap() is successful but it fails to reserve at the requested address 2468 anon_munmap(addr, bytes); 2469 } 2470 2471 int i; 2472 for (i = 0; i < max_tries; ++i) { 2473 base[i] = reserve_memory(bytes); 2474 2475 if (base[i] != NULL) { 2476 // Is this the block we wanted? 2477 if (base[i] == requested_addr) { 2478 size[i] = bytes; 2479 break; 2480 } 2481 2482 // Does this overlap the block we wanted? Give back the overlapped 2483 // parts and try again. 2484 2485 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2486 if (top_overlap >= 0 && top_overlap < bytes) { 2487 unmap_memory(base[i], top_overlap); 2488 base[i] += top_overlap; 2489 size[i] = bytes - top_overlap; 2490 } else { 2491 size_t bottom_overlap = base[i] + bytes - requested_addr; 2492 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2493 unmap_memory(requested_addr, bottom_overlap); 2494 size[i] = bytes - bottom_overlap; 2495 } else { 2496 size[i] = bytes; 2497 } 2498 } 2499 } 2500 } 2501 2502 // Give back the unused reserved pieces. 2503 2504 for (int j = 0; j < i; ++j) { 2505 if (base[j] != NULL) { 2506 unmap_memory(base[j], size[j]); 2507 } 2508 } 2509 2510 if (i < max_tries) { 2511 return requested_addr; 2512 } else { 2513 return NULL; 2514 } 2515} 2516 2517size_t os::read(int fd, void *buf, unsigned int nBytes) { 2518 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2519} 2520 2521size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) { 2522 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset)); 2523} 2524 2525void os::naked_short_sleep(jlong ms) { 2526 struct timespec req; 2527 2528 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2529 req.tv_sec = 0; 2530 if (ms > 0) { 2531 req.tv_nsec = (ms % 1000) * 1000000; 2532 } else { 2533 req.tv_nsec = 1; 2534 } 2535 2536 nanosleep(&req, NULL); 2537 2538 return; 2539} 2540 2541// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2542void os::infinite_sleep() { 2543 while (true) { // sleep forever ... 2544 ::sleep(100); // ... 100 seconds at a time 2545 } 2546} 2547 2548// Used to convert frequent JVM_Yield() to nops 2549bool os::dont_yield() { 2550 return DontYieldALot; 2551} 2552 2553void os::naked_yield() { 2554 sched_yield(); 2555} 2556 2557//////////////////////////////////////////////////////////////////////////////// 2558// thread priority support 2559 2560// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2561// only supports dynamic priority, static priority must be zero. For real-time 2562// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2563// However, for large multi-threaded applications, SCHED_RR is not only slower 2564// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2565// of 5 runs - Sep 2005). 2566// 2567// The following code actually changes the niceness of kernel-thread/LWP. It 2568// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2569// not the entire user process, and user level threads are 1:1 mapped to kernel 2570// threads. It has always been the case, but could change in the future. For 2571// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2572// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2573 2574#if !defined(__APPLE__) 2575int os::java_to_os_priority[CriticalPriority + 1] = { 2576 19, // 0 Entry should never be used 2577 2578 0, // 1 MinPriority 2579 3, // 2 2580 6, // 3 2581 2582 10, // 4 2583 15, // 5 NormPriority 2584 18, // 6 2585 2586 21, // 7 2587 25, // 8 2588 28, // 9 NearMaxPriority 2589 2590 31, // 10 MaxPriority 2591 2592 31 // 11 CriticalPriority 2593}; 2594#else 2595// Using Mach high-level priority assignments 2596int os::java_to_os_priority[CriticalPriority + 1] = { 2597 0, // 0 Entry should never be used (MINPRI_USER) 2598 2599 27, // 1 MinPriority 2600 28, // 2 2601 29, // 3 2602 2603 30, // 4 2604 31, // 5 NormPriority (BASEPRI_DEFAULT) 2605 32, // 6 2606 2607 33, // 7 2608 34, // 8 2609 35, // 9 NearMaxPriority 2610 2611 36, // 10 MaxPriority 2612 2613 36 // 11 CriticalPriority 2614}; 2615#endif 2616 2617static int prio_init() { 2618 if (ThreadPriorityPolicy == 1) { 2619 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2620 // if effective uid is not root. Perhaps, a more elegant way of doing 2621 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2622 if (geteuid() != 0) { 2623 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2624 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2625 } 2626 ThreadPriorityPolicy = 0; 2627 } 2628 } 2629 if (UseCriticalJavaThreadPriority) { 2630 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2631 } 2632 return 0; 2633} 2634 2635OSReturn os::set_native_priority(Thread* thread, int newpri) { 2636 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2637 2638#ifdef __OpenBSD__ 2639 // OpenBSD pthread_setprio starves low priority threads 2640 return OS_OK; 2641#elif defined(__FreeBSD__) 2642 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2643#elif defined(__APPLE__) || defined(__NetBSD__) 2644 struct sched_param sp; 2645 int policy; 2646 pthread_t self = pthread_self(); 2647 2648 if (pthread_getschedparam(self, &policy, &sp) != 0) { 2649 return OS_ERR; 2650 } 2651 2652 sp.sched_priority = newpri; 2653 if (pthread_setschedparam(self, policy, &sp) != 0) { 2654 return OS_ERR; 2655 } 2656 2657 return OS_OK; 2658#else 2659 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2660 return (ret == 0) ? OS_OK : OS_ERR; 2661#endif 2662} 2663 2664OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2665 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2666 *priority_ptr = java_to_os_priority[NormPriority]; 2667 return OS_OK; 2668 } 2669 2670 errno = 0; 2671#if defined(__OpenBSD__) || defined(__FreeBSD__) 2672 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2673#elif defined(__APPLE__) || defined(__NetBSD__) 2674 int policy; 2675 struct sched_param sp; 2676 2677 pthread_getschedparam(pthread_self(), &policy, &sp); 2678 *priority_ptr = sp.sched_priority; 2679#else 2680 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2681#endif 2682 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2683} 2684 2685// Hint to the underlying OS that a task switch would not be good. 2686// Void return because it's a hint and can fail. 2687void os::hint_no_preempt() {} 2688 2689//////////////////////////////////////////////////////////////////////////////// 2690// suspend/resume support 2691 2692// the low-level signal-based suspend/resume support is a remnant from the 2693// old VM-suspension that used to be for java-suspension, safepoints etc, 2694// within hotspot. Now there is a single use-case for this: 2695// - calling get_thread_pc() on the VMThread by the flat-profiler task 2696// that runs in the watcher thread. 2697// The remaining code is greatly simplified from the more general suspension 2698// code that used to be used. 2699// 2700// The protocol is quite simple: 2701// - suspend: 2702// - sends a signal to the target thread 2703// - polls the suspend state of the osthread using a yield loop 2704// - target thread signal handler (SR_handler) sets suspend state 2705// and blocks in sigsuspend until continued 2706// - resume: 2707// - sets target osthread state to continue 2708// - sends signal to end the sigsuspend loop in the SR_handler 2709// 2710// Note that the SR_lock plays no role in this suspend/resume protocol. 2711 2712static void resume_clear_context(OSThread *osthread) { 2713 osthread->set_ucontext(NULL); 2714 osthread->set_siginfo(NULL); 2715} 2716 2717static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2718 osthread->set_ucontext(context); 2719 osthread->set_siginfo(siginfo); 2720} 2721 2722// Handler function invoked when a thread's execution is suspended or 2723// resumed. We have to be careful that only async-safe functions are 2724// called here (Note: most pthread functions are not async safe and 2725// should be avoided.) 2726// 2727// Note: sigwait() is a more natural fit than sigsuspend() from an 2728// interface point of view, but sigwait() prevents the signal hander 2729// from being run. libpthread would get very confused by not having 2730// its signal handlers run and prevents sigwait()'s use with the 2731// mutex granting granting signal. 2732// 2733// Currently only ever called on the VMThread or JavaThread 2734// 2735static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2736 // Save and restore errno to avoid confusing native code with EINTR 2737 // after sigsuspend. 2738 int old_errno = errno; 2739 2740 Thread* thread = Thread::current(); 2741 OSThread* osthread = thread->osthread(); 2742 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2743 2744 os::SuspendResume::State current = osthread->sr.state(); 2745 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2746 suspend_save_context(osthread, siginfo, context); 2747 2748 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2749 os::SuspendResume::State state = osthread->sr.suspended(); 2750 if (state == os::SuspendResume::SR_SUSPENDED) { 2751 sigset_t suspend_set; // signals for sigsuspend() 2752 2753 // get current set of blocked signals and unblock resume signal 2754 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2755 sigdelset(&suspend_set, SR_signum); 2756 2757 sr_semaphore.signal(); 2758 // wait here until we are resumed 2759 while (1) { 2760 sigsuspend(&suspend_set); 2761 2762 os::SuspendResume::State result = osthread->sr.running(); 2763 if (result == os::SuspendResume::SR_RUNNING) { 2764 sr_semaphore.signal(); 2765 break; 2766 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2767 ShouldNotReachHere(); 2768 } 2769 } 2770 2771 } else if (state == os::SuspendResume::SR_RUNNING) { 2772 // request was cancelled, continue 2773 } else { 2774 ShouldNotReachHere(); 2775 } 2776 2777 resume_clear_context(osthread); 2778 } else if (current == os::SuspendResume::SR_RUNNING) { 2779 // request was cancelled, continue 2780 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2781 // ignore 2782 } else { 2783 // ignore 2784 } 2785 2786 errno = old_errno; 2787} 2788 2789 2790static int SR_initialize() { 2791 struct sigaction act; 2792 char *s; 2793 // Get signal number to use for suspend/resume 2794 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2795 int sig = ::strtol(s, 0, 10); 2796 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769. 2797 sig < NSIG) { // Must be legal signal and fit into sigflags[]. 2798 SR_signum = sig; 2799 } else { 2800 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.", 2801 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum); 2802 } 2803 } 2804 2805 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2806 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2807 2808 sigemptyset(&SR_sigset); 2809 sigaddset(&SR_sigset, SR_signum); 2810 2811 // Set up signal handler for suspend/resume 2812 act.sa_flags = SA_RESTART|SA_SIGINFO; 2813 act.sa_handler = (void (*)(int)) SR_handler; 2814 2815 // SR_signum is blocked by default. 2816 // 4528190 - We also need to block pthread restart signal (32 on all 2817 // supported Bsd platforms). Note that BsdThreads need to block 2818 // this signal for all threads to work properly. So we don't have 2819 // to use hard-coded signal number when setting up the mask. 2820 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2821 2822 if (sigaction(SR_signum, &act, 0) == -1) { 2823 return -1; 2824 } 2825 2826 // Save signal flag 2827 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2828 return 0; 2829} 2830 2831static int sr_notify(OSThread* osthread) { 2832 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2833 assert_status(status == 0, status, "pthread_kill"); 2834 return status; 2835} 2836 2837// "Randomly" selected value for how long we want to spin 2838// before bailing out on suspending a thread, also how often 2839// we send a signal to a thread we want to resume 2840static const int RANDOMLY_LARGE_INTEGER = 1000000; 2841static const int RANDOMLY_LARGE_INTEGER2 = 100; 2842 2843// returns true on success and false on error - really an error is fatal 2844// but this seems the normal response to library errors 2845static bool do_suspend(OSThread* osthread) { 2846 assert(osthread->sr.is_running(), "thread should be running"); 2847 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2848 2849 // mark as suspended and send signal 2850 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2851 // failed to switch, state wasn't running? 2852 ShouldNotReachHere(); 2853 return false; 2854 } 2855 2856 if (sr_notify(osthread) != 0) { 2857 ShouldNotReachHere(); 2858 } 2859 2860 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2861 while (true) { 2862 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2863 break; 2864 } else { 2865 // timeout 2866 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2867 if (cancelled == os::SuspendResume::SR_RUNNING) { 2868 return false; 2869 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2870 // make sure that we consume the signal on the semaphore as well 2871 sr_semaphore.wait(); 2872 break; 2873 } else { 2874 ShouldNotReachHere(); 2875 return false; 2876 } 2877 } 2878 } 2879 2880 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2881 return true; 2882} 2883 2884static void do_resume(OSThread* osthread) { 2885 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2886 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2887 2888 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2889 // failed to switch to WAKEUP_REQUEST 2890 ShouldNotReachHere(); 2891 return; 2892 } 2893 2894 while (true) { 2895 if (sr_notify(osthread) == 0) { 2896 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2897 if (osthread->sr.is_running()) { 2898 return; 2899 } 2900 } 2901 } else { 2902 ShouldNotReachHere(); 2903 } 2904 } 2905 2906 guarantee(osthread->sr.is_running(), "Must be running!"); 2907} 2908 2909/////////////////////////////////////////////////////////////////////////////////// 2910// signal handling (except suspend/resume) 2911 2912// This routine may be used by user applications as a "hook" to catch signals. 2913// The user-defined signal handler must pass unrecognized signals to this 2914// routine, and if it returns true (non-zero), then the signal handler must 2915// return immediately. If the flag "abort_if_unrecognized" is true, then this 2916// routine will never retun false (zero), but instead will execute a VM panic 2917// routine kill the process. 2918// 2919// If this routine returns false, it is OK to call it again. This allows 2920// the user-defined signal handler to perform checks either before or after 2921// the VM performs its own checks. Naturally, the user code would be making 2922// a serious error if it tried to handle an exception (such as a null check 2923// or breakpoint) that the VM was generating for its own correct operation. 2924// 2925// This routine may recognize any of the following kinds of signals: 2926// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2927// It should be consulted by handlers for any of those signals. 2928// 2929// The caller of this routine must pass in the three arguments supplied 2930// to the function referred to in the "sa_sigaction" (not the "sa_handler") 2931// field of the structure passed to sigaction(). This routine assumes that 2932// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2933// 2934// Note that the VM will print warnings if it detects conflicting signal 2935// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2936// 2937extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2938 void* ucontext, 2939 int abort_if_unrecognized); 2940 2941void signalHandler(int sig, siginfo_t* info, void* uc) { 2942 assert(info != NULL && uc != NULL, "it must be old kernel"); 2943 int orig_errno = errno; // Preserve errno value over signal handler. 2944 JVM_handle_bsd_signal(sig, info, uc, true); 2945 errno = orig_errno; 2946} 2947 2948 2949// This boolean allows users to forward their own non-matching signals 2950// to JVM_handle_bsd_signal, harmlessly. 2951bool os::Bsd::signal_handlers_are_installed = false; 2952 2953// For signal-chaining 2954struct sigaction sigact[NSIG]; 2955uint32_t sigs = 0; 2956#if (32 < NSIG-1) 2957#error "Not all signals can be encoded in sigs. Adapt its type!" 2958#endif 2959bool os::Bsd::libjsig_is_loaded = false; 2960typedef struct sigaction *(*get_signal_t)(int); 2961get_signal_t os::Bsd::get_signal_action = NULL; 2962 2963struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2964 struct sigaction *actp = NULL; 2965 2966 if (libjsig_is_loaded) { 2967 // Retrieve the old signal handler from libjsig 2968 actp = (*get_signal_action)(sig); 2969 } 2970 if (actp == NULL) { 2971 // Retrieve the preinstalled signal handler from jvm 2972 actp = get_preinstalled_handler(sig); 2973 } 2974 2975 return actp; 2976} 2977 2978static bool call_chained_handler(struct sigaction *actp, int sig, 2979 siginfo_t *siginfo, void *context) { 2980 // Call the old signal handler 2981 if (actp->sa_handler == SIG_DFL) { 2982 // It's more reasonable to let jvm treat it as an unexpected exception 2983 // instead of taking the default action. 2984 return false; 2985 } else if (actp->sa_handler != SIG_IGN) { 2986 if ((actp->sa_flags & SA_NODEFER) == 0) { 2987 // automaticlly block the signal 2988 sigaddset(&(actp->sa_mask), sig); 2989 } 2990 2991 sa_handler_t hand; 2992 sa_sigaction_t sa; 2993 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 2994 // retrieve the chained handler 2995 if (siginfo_flag_set) { 2996 sa = actp->sa_sigaction; 2997 } else { 2998 hand = actp->sa_handler; 2999 } 3000 3001 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3002 actp->sa_handler = SIG_DFL; 3003 } 3004 3005 // try to honor the signal mask 3006 sigset_t oset; 3007 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3008 3009 // call into the chained handler 3010 if (siginfo_flag_set) { 3011 (*sa)(sig, siginfo, context); 3012 } else { 3013 (*hand)(sig); 3014 } 3015 3016 // restore the signal mask 3017 pthread_sigmask(SIG_SETMASK, &oset, 0); 3018 } 3019 // Tell jvm's signal handler the signal is taken care of. 3020 return true; 3021} 3022 3023bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3024 bool chained = false; 3025 // signal-chaining 3026 if (UseSignalChaining) { 3027 struct sigaction *actp = get_chained_signal_action(sig); 3028 if (actp != NULL) { 3029 chained = call_chained_handler(actp, sig, siginfo, context); 3030 } 3031 } 3032 return chained; 3033} 3034 3035struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3036 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) { 3037 return &sigact[sig]; 3038 } 3039 return NULL; 3040} 3041 3042void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3043 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 3044 sigact[sig] = oldAct; 3045 sigs |= (uint32_t)1 << (sig-1); 3046} 3047 3048// for diagnostic 3049int sigflags[NSIG]; 3050 3051int os::Bsd::get_our_sigflags(int sig) { 3052 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 3053 return sigflags[sig]; 3054} 3055 3056void os::Bsd::set_our_sigflags(int sig, int flags) { 3057 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 3058 if (sig > 0 && sig < NSIG) { 3059 sigflags[sig] = flags; 3060 } 3061} 3062 3063void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3064 // Check for overwrite. 3065 struct sigaction oldAct; 3066 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3067 3068 void* oldhand = oldAct.sa_sigaction 3069 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3070 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3071 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3072 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3073 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3074 if (AllowUserSignalHandlers || !set_installed) { 3075 // Do not overwrite; user takes responsibility to forward to us. 3076 return; 3077 } else if (UseSignalChaining) { 3078 // save the old handler in jvm 3079 save_preinstalled_handler(sig, oldAct); 3080 // libjsig also interposes the sigaction() call below and saves the 3081 // old sigaction on it own. 3082 } else { 3083 fatal("Encountered unexpected pre-existing sigaction handler " 3084 "%#lx for signal %d.", (long)oldhand, sig); 3085 } 3086 } 3087 3088 struct sigaction sigAct; 3089 sigfillset(&(sigAct.sa_mask)); 3090 sigAct.sa_handler = SIG_DFL; 3091 if (!set_installed) { 3092 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3093 } else { 3094 sigAct.sa_sigaction = signalHandler; 3095 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3096 } 3097#ifdef __APPLE__ 3098 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3099 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3100 // if the signal handler declares it will handle it on alternate stack. 3101 // Notice we only declare we will handle it on alt stack, but we are not 3102 // actually going to use real alt stack - this is just a workaround. 3103 // Please see ux_exception.c, method catch_mach_exception_raise for details 3104 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3105 if (sig == SIGSEGV) { 3106 sigAct.sa_flags |= SA_ONSTACK; 3107 } 3108#endif 3109 3110 // Save flags, which are set by ours 3111 assert(sig > 0 && sig < NSIG, "vm signal out of expected range"); 3112 sigflags[sig] = sigAct.sa_flags; 3113 3114 int ret = sigaction(sig, &sigAct, &oldAct); 3115 assert(ret == 0, "check"); 3116 3117 void* oldhand2 = oldAct.sa_sigaction 3118 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3119 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3120 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3121} 3122 3123// install signal handlers for signals that HotSpot needs to 3124// handle in order to support Java-level exception handling. 3125 3126void os::Bsd::install_signal_handlers() { 3127 if (!signal_handlers_are_installed) { 3128 signal_handlers_are_installed = true; 3129 3130 // signal-chaining 3131 typedef void (*signal_setting_t)(); 3132 signal_setting_t begin_signal_setting = NULL; 3133 signal_setting_t end_signal_setting = NULL; 3134 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3135 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3136 if (begin_signal_setting != NULL) { 3137 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3138 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3139 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3140 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3141 libjsig_is_loaded = true; 3142 assert(UseSignalChaining, "should enable signal-chaining"); 3143 } 3144 if (libjsig_is_loaded) { 3145 // Tell libjsig jvm is setting signal handlers 3146 (*begin_signal_setting)(); 3147 } 3148 3149 set_signal_handler(SIGSEGV, true); 3150 set_signal_handler(SIGPIPE, true); 3151 set_signal_handler(SIGBUS, true); 3152 set_signal_handler(SIGILL, true); 3153 set_signal_handler(SIGFPE, true); 3154 set_signal_handler(SIGXFSZ, true); 3155 3156#if defined(__APPLE__) 3157 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3158 // signals caught and handled by the JVM. To work around this, we reset the mach task 3159 // signal handler that's placed on our process by CrashReporter. This disables 3160 // CrashReporter-based reporting. 3161 // 3162 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3163 // on caught fatal signals. 3164 // 3165 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3166 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3167 // exception handling, while leaving the standard BSD signal handlers functional. 3168 kern_return_t kr; 3169 kr = task_set_exception_ports(mach_task_self(), 3170 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3171 MACH_PORT_NULL, 3172 EXCEPTION_STATE_IDENTITY, 3173 MACHINE_THREAD_STATE); 3174 3175 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3176#endif 3177 3178 if (libjsig_is_loaded) { 3179 // Tell libjsig jvm finishes setting signal handlers 3180 (*end_signal_setting)(); 3181 } 3182 3183 // We don't activate signal checker if libjsig is in place, we trust ourselves 3184 // and if UserSignalHandler is installed all bets are off 3185 if (CheckJNICalls) { 3186 if (libjsig_is_loaded) { 3187 if (PrintJNIResolving) { 3188 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3189 } 3190 check_signals = false; 3191 } 3192 if (AllowUserSignalHandlers) { 3193 if (PrintJNIResolving) { 3194 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3195 } 3196 check_signals = false; 3197 } 3198 } 3199 } 3200} 3201 3202 3203///// 3204// glibc on Bsd platform uses non-documented flag 3205// to indicate, that some special sort of signal 3206// trampoline is used. 3207// We will never set this flag, and we should 3208// ignore this flag in our diagnostic 3209#ifdef SIGNIFICANT_SIGNAL_MASK 3210 #undef SIGNIFICANT_SIGNAL_MASK 3211#endif 3212#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3213 3214static const char* get_signal_handler_name(address handler, 3215 char* buf, int buflen) { 3216 int offset; 3217 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3218 if (found) { 3219 // skip directory names 3220 const char *p1, *p2; 3221 p1 = buf; 3222 size_t len = strlen(os::file_separator()); 3223 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3224 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3225 } else { 3226 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3227 } 3228 return buf; 3229} 3230 3231static void print_signal_handler(outputStream* st, int sig, 3232 char* buf, size_t buflen) { 3233 struct sigaction sa; 3234 3235 sigaction(sig, NULL, &sa); 3236 3237 // See comment for SIGNIFICANT_SIGNAL_MASK define 3238 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3239 3240 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3241 3242 address handler = (sa.sa_flags & SA_SIGINFO) 3243 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3244 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3245 3246 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3247 st->print("SIG_DFL"); 3248 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3249 st->print("SIG_IGN"); 3250 } else { 3251 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3252 } 3253 3254 st->print(", sa_mask[0]="); 3255 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3256 3257 address rh = VMError::get_resetted_sighandler(sig); 3258 // May be, handler was resetted by VMError? 3259 if (rh != NULL) { 3260 handler = rh; 3261 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3262 } 3263 3264 st->print(", sa_flags="); 3265 os::Posix::print_sa_flags(st, sa.sa_flags); 3266 3267 // Check: is it our handler? 3268 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3269 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3270 // It is our signal handler 3271 // check for flags, reset system-used one! 3272 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3273 st->print( 3274 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3275 os::Bsd::get_our_sigflags(sig)); 3276 } 3277 } 3278 st->cr(); 3279} 3280 3281 3282#define DO_SIGNAL_CHECK(sig) \ 3283 do { \ 3284 if (!sigismember(&check_signal_done, sig)) { \ 3285 os::Bsd::check_signal_handler(sig); \ 3286 } \ 3287 } while (0) 3288 3289// This method is a periodic task to check for misbehaving JNI applications 3290// under CheckJNI, we can add any periodic checks here 3291 3292void os::run_periodic_checks() { 3293 3294 if (check_signals == false) return; 3295 3296 // SEGV and BUS if overridden could potentially prevent 3297 // generation of hs*.log in the event of a crash, debugging 3298 // such a case can be very challenging, so we absolutely 3299 // check the following for a good measure: 3300 DO_SIGNAL_CHECK(SIGSEGV); 3301 DO_SIGNAL_CHECK(SIGILL); 3302 DO_SIGNAL_CHECK(SIGFPE); 3303 DO_SIGNAL_CHECK(SIGBUS); 3304 DO_SIGNAL_CHECK(SIGPIPE); 3305 DO_SIGNAL_CHECK(SIGXFSZ); 3306 3307 3308 // ReduceSignalUsage allows the user to override these handlers 3309 // see comments at the very top and jvm_solaris.h 3310 if (!ReduceSignalUsage) { 3311 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3312 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3313 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3314 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3315 } 3316 3317 DO_SIGNAL_CHECK(SR_signum); 3318} 3319 3320typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3321 3322static os_sigaction_t os_sigaction = NULL; 3323 3324void os::Bsd::check_signal_handler(int sig) { 3325 char buf[O_BUFLEN]; 3326 address jvmHandler = NULL; 3327 3328 3329 struct sigaction act; 3330 if (os_sigaction == NULL) { 3331 // only trust the default sigaction, in case it has been interposed 3332 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3333 if (os_sigaction == NULL) return; 3334 } 3335 3336 os_sigaction(sig, (struct sigaction*)NULL, &act); 3337 3338 3339 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3340 3341 address thisHandler = (act.sa_flags & SA_SIGINFO) 3342 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3343 : CAST_FROM_FN_PTR(address, act.sa_handler); 3344 3345 3346 switch (sig) { 3347 case SIGSEGV: 3348 case SIGBUS: 3349 case SIGFPE: 3350 case SIGPIPE: 3351 case SIGILL: 3352 case SIGXFSZ: 3353 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3354 break; 3355 3356 case SHUTDOWN1_SIGNAL: 3357 case SHUTDOWN2_SIGNAL: 3358 case SHUTDOWN3_SIGNAL: 3359 case BREAK_SIGNAL: 3360 jvmHandler = (address)user_handler(); 3361 break; 3362 3363 default: 3364 if (sig == SR_signum) { 3365 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3366 } else { 3367 return; 3368 } 3369 break; 3370 } 3371 3372 if (thisHandler != jvmHandler) { 3373 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3374 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3375 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3376 // No need to check this sig any longer 3377 sigaddset(&check_signal_done, sig); 3378 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3379 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3380 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3381 exception_name(sig, buf, O_BUFLEN)); 3382 } 3383 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3384 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3385 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3386 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3387 // No need to check this sig any longer 3388 sigaddset(&check_signal_done, sig); 3389 } 3390 3391 // Dump all the signal 3392 if (sigismember(&check_signal_done, sig)) { 3393 print_signal_handlers(tty, buf, O_BUFLEN); 3394 } 3395} 3396 3397extern void report_error(char* file_name, int line_no, char* title, 3398 char* format, ...); 3399 3400// this is called _before_ the most of global arguments have been parsed 3401void os::init(void) { 3402 char dummy; // used to get a guess on initial stack address 3403// first_hrtime = gethrtime(); 3404 3405 // With BsdThreads the JavaMain thread pid (primordial thread) 3406 // is different than the pid of the java launcher thread. 3407 // So, on Bsd, the launcher thread pid is passed to the VM 3408 // via the sun.java.launcher.pid property. 3409 // Use this property instead of getpid() if it was correctly passed. 3410 // See bug 6351349. 3411 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3412 3413 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3414 3415 clock_tics_per_sec = CLK_TCK; 3416 3417 init_random(1234567); 3418 3419 ThreadCritical::initialize(); 3420 3421 Bsd::set_page_size(getpagesize()); 3422 if (Bsd::page_size() == -1) { 3423 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", strerror(errno)); 3424 } 3425 init_page_sizes((size_t) Bsd::page_size()); 3426 3427 Bsd::initialize_system_info(); 3428 3429 // main_thread points to the aboriginal thread 3430 Bsd::_main_thread = pthread_self(); 3431 3432 Bsd::clock_init(); 3433 initial_time_count = javaTimeNanos(); 3434 3435#ifdef __APPLE__ 3436 // XXXDARWIN 3437 // Work around the unaligned VM callbacks in hotspot's 3438 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3439 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3440 // alignment when doing symbol lookup. To work around this, we force early 3441 // binding of all symbols now, thus binding when alignment is known-good. 3442 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3443#endif 3444} 3445 3446// To install functions for atexit system call 3447extern "C" { 3448 static void perfMemory_exit_helper() { 3449 perfMemory_exit(); 3450 } 3451} 3452 3453// this is called _after_ the global arguments have been parsed 3454jint os::init_2(void) { 3455 // Allocate a single page and mark it as readable for safepoint polling 3456 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3457 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3458 3459 os::set_polling_page(polling_page); 3460 3461#ifndef PRODUCT 3462 if (Verbose && PrintMiscellaneous) { 3463 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", 3464 (intptr_t)polling_page); 3465 } 3466#endif 3467 3468 if (!UseMembar) { 3469 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3470 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3471 os::set_memory_serialize_page(mem_serialize_page); 3472 3473#ifndef PRODUCT 3474 if (Verbose && PrintMiscellaneous) { 3475 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", 3476 (intptr_t)mem_serialize_page); 3477 } 3478#endif 3479 } 3480 3481 // initialize suspend/resume support - must do this before signal_sets_init() 3482 if (SR_initialize() != 0) { 3483 perror("SR_initialize failed"); 3484 return JNI_ERR; 3485 } 3486 3487 Bsd::signal_sets_init(); 3488 Bsd::install_signal_handlers(); 3489 3490 // Check minimum allowable stack size for thread creation and to initialize 3491 // the java system classes, including StackOverflowError - depends on page 3492 // size. Add a page for compiler2 recursion in main thread. 3493 // Add in 2*BytesPerWord times page size to account for VM stack during 3494 // class initialization depending on 32 or 64 bit VM. 3495 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3496 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3497 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3498 3499 size_t threadStackSizeInBytes = ThreadStackSize * K; 3500 if (threadStackSizeInBytes != 0 && 3501 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3502 tty->print_cr("\nThe stack size specified is too small, " 3503 "Specify at least %dk", 3504 os::Bsd::min_stack_allowed/ K); 3505 return JNI_ERR; 3506 } 3507 3508 // Make the stack size a multiple of the page size so that 3509 // the yellow/red zones can be guarded. 3510 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3511 vm_page_size())); 3512 3513 if (MaxFDLimit) { 3514 // set the number of file descriptors to max. print out error 3515 // if getrlimit/setrlimit fails but continue regardless. 3516 struct rlimit nbr_files; 3517 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3518 if (status != 0) { 3519 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3520 perror("os::init_2 getrlimit failed"); 3521 } 3522 } else { 3523 nbr_files.rlim_cur = nbr_files.rlim_max; 3524 3525#ifdef __APPLE__ 3526 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3527 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3528 // be used instead 3529 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3530#endif 3531 3532 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3533 if (status != 0) { 3534 if (PrintMiscellaneous && (Verbose || WizardMode)) { 3535 perror("os::init_2 setrlimit failed"); 3536 } 3537 } 3538 } 3539 } 3540 3541 // at-exit methods are called in the reverse order of their registration. 3542 // atexit functions are called on return from main or as a result of a 3543 // call to exit(3C). There can be only 32 of these functions registered 3544 // and atexit() does not set errno. 3545 3546 if (PerfAllowAtExitRegistration) { 3547 // only register atexit functions if PerfAllowAtExitRegistration is set. 3548 // atexit functions can be delayed until process exit time, which 3549 // can be problematic for embedded VM situations. Embedded VMs should 3550 // call DestroyJavaVM() to assure that VM resources are released. 3551 3552 // note: perfMemory_exit_helper atexit function may be removed in 3553 // the future if the appropriate cleanup code can be added to the 3554 // VM_Exit VMOperation's doit method. 3555 if (atexit(perfMemory_exit_helper) != 0) { 3556 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3557 } 3558 } 3559 3560 // initialize thread priority policy 3561 prio_init(); 3562 3563#ifdef __APPLE__ 3564 // dynamically link to objective c gc registration 3565 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3566 if (handleLibObjc != NULL) { 3567 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3568 } 3569#endif 3570 3571 return JNI_OK; 3572} 3573 3574// Mark the polling page as unreadable 3575void os::make_polling_page_unreadable(void) { 3576 if (!guard_memory((char*)_polling_page, Bsd::page_size())) { 3577 fatal("Could not disable polling page"); 3578 } 3579} 3580 3581// Mark the polling page as readable 3582void os::make_polling_page_readable(void) { 3583 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3584 fatal("Could not enable polling page"); 3585 } 3586} 3587 3588int os::active_processor_count() { 3589 return _processor_count; 3590} 3591 3592void os::set_native_thread_name(const char *name) { 3593#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3594 // This is only supported in Snow Leopard and beyond 3595 if (name != NULL) { 3596 // Add a "Java: " prefix to the name 3597 char buf[MAXTHREADNAMESIZE]; 3598 snprintf(buf, sizeof(buf), "Java: %s", name); 3599 pthread_setname_np(buf); 3600 } 3601#endif 3602} 3603 3604bool os::distribute_processes(uint length, uint* distribution) { 3605 // Not yet implemented. 3606 return false; 3607} 3608 3609bool os::bind_to_processor(uint processor_id) { 3610 // Not yet implemented. 3611 return false; 3612} 3613 3614void os::SuspendedThreadTask::internal_do_task() { 3615 if (do_suspend(_thread->osthread())) { 3616 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3617 do_task(context); 3618 do_resume(_thread->osthread()); 3619 } 3620} 3621 3622/// 3623class PcFetcher : public os::SuspendedThreadTask { 3624 public: 3625 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3626 ExtendedPC result(); 3627 protected: 3628 void do_task(const os::SuspendedThreadTaskContext& context); 3629 private: 3630 ExtendedPC _epc; 3631}; 3632 3633ExtendedPC PcFetcher::result() { 3634 guarantee(is_done(), "task is not done yet."); 3635 return _epc; 3636} 3637 3638void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3639 Thread* thread = context.thread(); 3640 OSThread* osthread = thread->osthread(); 3641 if (osthread->ucontext() != NULL) { 3642 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3643 } else { 3644 // NULL context is unexpected, double-check this is the VMThread 3645 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3646 } 3647} 3648 3649// Suspends the target using the signal mechanism and then grabs the PC before 3650// resuming the target. Used by the flat-profiler only 3651ExtendedPC os::get_thread_pc(Thread* thread) { 3652 // Make sure that it is called by the watcher for the VMThread 3653 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3654 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3655 3656 PcFetcher fetcher(thread); 3657 fetcher.run(); 3658 return fetcher.result(); 3659} 3660 3661//////////////////////////////////////////////////////////////////////////////// 3662// debug support 3663 3664bool os::find(address addr, outputStream* st) { 3665 Dl_info dlinfo; 3666 memset(&dlinfo, 0, sizeof(dlinfo)); 3667 if (dladdr(addr, &dlinfo) != 0) { 3668 st->print(PTR_FORMAT ": ", addr); 3669 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3670 st->print("%s+%#x", dlinfo.dli_sname, 3671 addr - (intptr_t)dlinfo.dli_saddr); 3672 } else if (dlinfo.dli_fbase != NULL) { 3673 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3674 } else { 3675 st->print("<absolute address>"); 3676 } 3677 if (dlinfo.dli_fname != NULL) { 3678 st->print(" in %s", dlinfo.dli_fname); 3679 } 3680 if (dlinfo.dli_fbase != NULL) { 3681 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3682 } 3683 st->cr(); 3684 3685 if (Verbose) { 3686 // decode some bytes around the PC 3687 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3688 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3689 address lowest = (address) dlinfo.dli_sname; 3690 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3691 if (begin < lowest) begin = lowest; 3692 Dl_info dlinfo2; 3693 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3694 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) { 3695 end = (address) dlinfo2.dli_saddr; 3696 } 3697 Disassembler::decode(begin, end, st); 3698 } 3699 return true; 3700 } 3701 return false; 3702} 3703 3704//////////////////////////////////////////////////////////////////////////////// 3705// misc 3706 3707// This does not do anything on Bsd. This is basically a hook for being 3708// able to use structured exception handling (thread-local exception filters) 3709// on, e.g., Win32. 3710void os::os_exception_wrapper(java_call_t f, JavaValue* value, 3711 const methodHandle& method, JavaCallArguments* args, 3712 Thread* thread) { 3713 f(value, method, args, thread); 3714} 3715 3716void os::print_statistics() { 3717} 3718 3719bool os::message_box(const char* title, const char* message) { 3720 int i; 3721 fdStream err(defaultStream::error_fd()); 3722 for (i = 0; i < 78; i++) err.print_raw("="); 3723 err.cr(); 3724 err.print_raw_cr(title); 3725 for (i = 0; i < 78; i++) err.print_raw("-"); 3726 err.cr(); 3727 err.print_raw_cr(message); 3728 for (i = 0; i < 78; i++) err.print_raw("="); 3729 err.cr(); 3730 3731 char buf[16]; 3732 // Prevent process from exiting upon "read error" without consuming all CPU 3733 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3734 3735 return buf[0] == 'y' || buf[0] == 'Y'; 3736} 3737 3738int os::stat(const char *path, struct stat *sbuf) { 3739 char pathbuf[MAX_PATH]; 3740 if (strlen(path) > MAX_PATH - 1) { 3741 errno = ENAMETOOLONG; 3742 return -1; 3743 } 3744 os::native_path(strcpy(pathbuf, path)); 3745 return ::stat(pathbuf, sbuf); 3746} 3747 3748bool os::check_heap(bool force) { 3749 return true; 3750} 3751 3752// Is a (classpath) directory empty? 3753bool os::dir_is_empty(const char* path) { 3754 DIR *dir = NULL; 3755 struct dirent *ptr; 3756 3757 dir = opendir(path); 3758 if (dir == NULL) return true; 3759 3760 // Scan the directory 3761 bool result = true; 3762 char buf[sizeof(struct dirent) + MAX_PATH]; 3763 while (result && (ptr = ::readdir(dir)) != NULL) { 3764 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3765 result = false; 3766 } 3767 } 3768 closedir(dir); 3769 return result; 3770} 3771 3772// This code originates from JDK's sysOpen and open64_w 3773// from src/solaris/hpi/src/system_md.c 3774 3775int os::open(const char *path, int oflag, int mode) { 3776 if (strlen(path) > MAX_PATH - 1) { 3777 errno = ENAMETOOLONG; 3778 return -1; 3779 } 3780 int fd; 3781 3782 fd = ::open(path, oflag, mode); 3783 if (fd == -1) return -1; 3784 3785 // If the open succeeded, the file might still be a directory 3786 { 3787 struct stat buf; 3788 int ret = ::fstat(fd, &buf); 3789 int st_mode = buf.st_mode; 3790 3791 if (ret != -1) { 3792 if ((st_mode & S_IFMT) == S_IFDIR) { 3793 errno = EISDIR; 3794 ::close(fd); 3795 return -1; 3796 } 3797 } else { 3798 ::close(fd); 3799 return -1; 3800 } 3801 } 3802 3803 // All file descriptors that are opened in the JVM and not 3804 // specifically destined for a subprocess should have the 3805 // close-on-exec flag set. If we don't set it, then careless 3rd 3806 // party native code might fork and exec without closing all 3807 // appropriate file descriptors (e.g. as we do in closeDescriptors in 3808 // UNIXProcess.c), and this in turn might: 3809 // 3810 // - cause end-of-file to fail to be detected on some file 3811 // descriptors, resulting in mysterious hangs, or 3812 // 3813 // - might cause an fopen in the subprocess to fail on a system 3814 // suffering from bug 1085341. 3815 // 3816 // (Yes, the default setting of the close-on-exec flag is a Unix 3817 // design flaw) 3818 // 3819 // See: 3820 // 1085341: 32-bit stdio routines should support file descriptors >255 3821 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3822 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3823 // 3824#ifdef FD_CLOEXEC 3825 { 3826 int flags = ::fcntl(fd, F_GETFD); 3827 if (flags != -1) { 3828 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3829 } 3830 } 3831#endif 3832 3833 return fd; 3834} 3835 3836 3837// create binary file, rewriting existing file if required 3838int os::create_binary_file(const char* path, bool rewrite_existing) { 3839 int oflags = O_WRONLY | O_CREAT; 3840 if (!rewrite_existing) { 3841 oflags |= O_EXCL; 3842 } 3843 return ::open(path, oflags, S_IREAD | S_IWRITE); 3844} 3845 3846// return current position of file pointer 3847jlong os::current_file_offset(int fd) { 3848 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3849} 3850 3851// move file pointer to the specified offset 3852jlong os::seek_to_file_offset(int fd, jlong offset) { 3853 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3854} 3855 3856// This code originates from JDK's sysAvailable 3857// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3858 3859int os::available(int fd, jlong *bytes) { 3860 jlong cur, end; 3861 int mode; 3862 struct stat buf; 3863 3864 if (::fstat(fd, &buf) >= 0) { 3865 mode = buf.st_mode; 3866 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3867 int n; 3868 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3869 *bytes = n; 3870 return 1; 3871 } 3872 } 3873 } 3874 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3875 return 0; 3876 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3877 return 0; 3878 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3879 return 0; 3880 } 3881 *bytes = end - cur; 3882 return 1; 3883} 3884 3885// Map a block of memory. 3886char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3887 char *addr, size_t bytes, bool read_only, 3888 bool allow_exec) { 3889 int prot; 3890 int flags; 3891 3892 if (read_only) { 3893 prot = PROT_READ; 3894 flags = MAP_SHARED; 3895 } else { 3896 prot = PROT_READ | PROT_WRITE; 3897 flags = MAP_PRIVATE; 3898 } 3899 3900 if (allow_exec) { 3901 prot |= PROT_EXEC; 3902 } 3903 3904 if (addr != NULL) { 3905 flags |= MAP_FIXED; 3906 } 3907 3908 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3909 fd, file_offset); 3910 if (mapped_address == MAP_FAILED) { 3911 return NULL; 3912 } 3913 return mapped_address; 3914} 3915 3916 3917// Remap a block of memory. 3918char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 3919 char *addr, size_t bytes, bool read_only, 3920 bool allow_exec) { 3921 // same as map_memory() on this OS 3922 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 3923 allow_exec); 3924} 3925 3926 3927// Unmap a block of memory. 3928bool os::pd_unmap_memory(char* addr, size_t bytes) { 3929 return munmap(addr, bytes) == 0; 3930} 3931 3932// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 3933// are used by JVM M&M and JVMTI to get user+sys or user CPU time 3934// of a thread. 3935// 3936// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 3937// the fast estimate available on the platform. 3938 3939jlong os::current_thread_cpu_time() { 3940#ifdef __APPLE__ 3941 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 3942#else 3943 Unimplemented(); 3944 return 0; 3945#endif 3946} 3947 3948jlong os::thread_cpu_time(Thread* thread) { 3949#ifdef __APPLE__ 3950 return os::thread_cpu_time(thread, true /* user + sys */); 3951#else 3952 Unimplemented(); 3953 return 0; 3954#endif 3955} 3956 3957jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 3958#ifdef __APPLE__ 3959 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 3960#else 3961 Unimplemented(); 3962 return 0; 3963#endif 3964} 3965 3966jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 3967#ifdef __APPLE__ 3968 struct thread_basic_info tinfo; 3969 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 3970 kern_return_t kr; 3971 thread_t mach_thread; 3972 3973 mach_thread = thread->osthread()->thread_id(); 3974 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 3975 if (kr != KERN_SUCCESS) { 3976 return -1; 3977 } 3978 3979 if (user_sys_cpu_time) { 3980 jlong nanos; 3981 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 3982 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 3983 return nanos; 3984 } else { 3985 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 3986 } 3987#else 3988 Unimplemented(); 3989 return 0; 3990#endif 3991} 3992 3993 3994void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 3995 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 3996 info_ptr->may_skip_backward = false; // elapsed time not wall time 3997 info_ptr->may_skip_forward = false; // elapsed time not wall time 3998 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 3999} 4000 4001void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4002 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4003 info_ptr->may_skip_backward = false; // elapsed time not wall time 4004 info_ptr->may_skip_forward = false; // elapsed time not wall time 4005 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4006} 4007 4008bool os::is_thread_cpu_time_supported() { 4009#ifdef __APPLE__ 4010 return true; 4011#else 4012 return false; 4013#endif 4014} 4015 4016// System loadavg support. Returns -1 if load average cannot be obtained. 4017// Bsd doesn't yet have a (official) notion of processor sets, 4018// so just return the system wide load average. 4019int os::loadavg(double loadavg[], int nelem) { 4020 return ::getloadavg(loadavg, nelem); 4021} 4022 4023void os::pause() { 4024 char filename[MAX_PATH]; 4025 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4026 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4027 } else { 4028 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4029 } 4030 4031 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4032 if (fd != -1) { 4033 struct stat buf; 4034 ::close(fd); 4035 while (::stat(filename, &buf) == 0) { 4036 (void)::poll(NULL, 0, 100); 4037 } 4038 } else { 4039 jio_fprintf(stderr, 4040 "Could not open pause file '%s', continuing immediately.\n", filename); 4041 } 4042} 4043 4044 4045// Refer to the comments in os_solaris.cpp park-unpark. The next two 4046// comment paragraphs are worth repeating here: 4047// 4048// Assumption: 4049// Only one parker can exist on an event, which is why we allocate 4050// them per-thread. Multiple unparkers can coexist. 4051// 4052// _Event serves as a restricted-range semaphore. 4053// -1 : thread is blocked, i.e. there is a waiter 4054// 0 : neutral: thread is running or ready, 4055// could have been signaled after a wait started 4056// 1 : signaled - thread is running or ready 4057// 4058// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4059// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4060// For specifics regarding the bug see GLIBC BUGID 261237 : 4061// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4062// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4063// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4064// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4065// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4066// and monitorenter when we're using 1-0 locking. All those operations may result in 4067// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4068// of libpthread avoids the problem, but isn't practical. 4069// 4070// Possible remedies: 4071// 4072// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4073// This is palliative and probabilistic, however. If the thread is preempted 4074// between the call to compute_abstime() and pthread_cond_timedwait(), more 4075// than the minimum period may have passed, and the abstime may be stale (in the 4076// past) resultin in a hang. Using this technique reduces the odds of a hang 4077// but the JVM is still vulnerable, particularly on heavily loaded systems. 4078// 4079// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4080// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4081// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4082// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4083// thread. 4084// 4085// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4086// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4087// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4088// This also works well. In fact it avoids kernel-level scalability impediments 4089// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4090// timers in a graceful fashion. 4091// 4092// 4. When the abstime value is in the past it appears that control returns 4093// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4094// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4095// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4096// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4097// It may be possible to avoid reinitialization by checking the return 4098// value from pthread_cond_timedwait(). In addition to reinitializing the 4099// condvar we must establish the invariant that cond_signal() is only called 4100// within critical sections protected by the adjunct mutex. This prevents 4101// cond_signal() from "seeing" a condvar that's in the midst of being 4102// reinitialized or that is corrupt. Sadly, this invariant obviates the 4103// desirable signal-after-unlock optimization that avoids futile context switching. 4104// 4105// I'm also concerned that some versions of NTPL might allocate an auxilliary 4106// structure when a condvar is used or initialized. cond_destroy() would 4107// release the helper structure. Our reinitialize-after-timedwait fix 4108// put excessive stress on malloc/free and locks protecting the c-heap. 4109// 4110// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4111// It may be possible to refine (4) by checking the kernel and NTPL verisons 4112// and only enabling the work-around for vulnerable environments. 4113 4114// utility to compute the abstime argument to timedwait: 4115// millis is the relative timeout time 4116// abstime will be the absolute timeout time 4117// TODO: replace compute_abstime() with unpackTime() 4118 4119static struct timespec* compute_abstime(struct timespec* abstime, 4120 jlong millis) { 4121 if (millis < 0) millis = 0; 4122 struct timeval now; 4123 int status = gettimeofday(&now, NULL); 4124 assert(status == 0, "gettimeofday"); 4125 jlong seconds = millis / 1000; 4126 millis %= 1000; 4127 if (seconds > 50000000) { // see man cond_timedwait(3T) 4128 seconds = 50000000; 4129 } 4130 abstime->tv_sec = now.tv_sec + seconds; 4131 long usec = now.tv_usec + millis * 1000; 4132 if (usec >= 1000000) { 4133 abstime->tv_sec += 1; 4134 usec -= 1000000; 4135 } 4136 abstime->tv_nsec = usec * 1000; 4137 return abstime; 4138} 4139 4140void os::PlatformEvent::park() { // AKA "down()" 4141 // Transitions for _Event: 4142 // -1 => -1 : illegal 4143 // 1 => 0 : pass - return immediately 4144 // 0 => -1 : block; then set _Event to 0 before returning 4145 4146 // Invariant: Only the thread associated with the Event/PlatformEvent 4147 // may call park(). 4148 // TODO: assert that _Assoc != NULL or _Assoc == Self 4149 assert(_nParked == 0, "invariant"); 4150 4151 int v; 4152 for (;;) { 4153 v = _Event; 4154 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4155 } 4156 guarantee(v >= 0, "invariant"); 4157 if (v == 0) { 4158 // Do this the hard way by blocking ... 4159 int status = pthread_mutex_lock(_mutex); 4160 assert_status(status == 0, status, "mutex_lock"); 4161 guarantee(_nParked == 0, "invariant"); 4162 ++_nParked; 4163 while (_Event < 0) { 4164 status = pthread_cond_wait(_cond, _mutex); 4165 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4166 // Treat this the same as if the wait was interrupted 4167 if (status == ETIMEDOUT) { status = EINTR; } 4168 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4169 } 4170 --_nParked; 4171 4172 _Event = 0; 4173 status = pthread_mutex_unlock(_mutex); 4174 assert_status(status == 0, status, "mutex_unlock"); 4175 // Paranoia to ensure our locked and lock-free paths interact 4176 // correctly with each other. 4177 OrderAccess::fence(); 4178 } 4179 guarantee(_Event >= 0, "invariant"); 4180} 4181 4182int os::PlatformEvent::park(jlong millis) { 4183 // Transitions for _Event: 4184 // -1 => -1 : illegal 4185 // 1 => 0 : pass - return immediately 4186 // 0 => -1 : block; then set _Event to 0 before returning 4187 4188 guarantee(_nParked == 0, "invariant"); 4189 4190 int v; 4191 for (;;) { 4192 v = _Event; 4193 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4194 } 4195 guarantee(v >= 0, "invariant"); 4196 if (v != 0) return OS_OK; 4197 4198 // We do this the hard way, by blocking the thread. 4199 // Consider enforcing a minimum timeout value. 4200 struct timespec abst; 4201 compute_abstime(&abst, millis); 4202 4203 int ret = OS_TIMEOUT; 4204 int status = pthread_mutex_lock(_mutex); 4205 assert_status(status == 0, status, "mutex_lock"); 4206 guarantee(_nParked == 0, "invariant"); 4207 ++_nParked; 4208 4209 // Object.wait(timo) will return because of 4210 // (a) notification 4211 // (b) timeout 4212 // (c) thread.interrupt 4213 // 4214 // Thread.interrupt and object.notify{All} both call Event::set. 4215 // That is, we treat thread.interrupt as a special case of notification. 4216 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4217 // We assume all ETIME returns are valid. 4218 // 4219 // TODO: properly differentiate simultaneous notify+interrupt. 4220 // In that case, we should propagate the notify to another waiter. 4221 4222 while (_Event < 0) { 4223 status = pthread_cond_timedwait(_cond, _mutex, &abst); 4224 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4225 pthread_cond_destroy(_cond); 4226 pthread_cond_init(_cond, NULL); 4227 } 4228 assert_status(status == 0 || status == EINTR || 4229 status == ETIMEDOUT, 4230 status, "cond_timedwait"); 4231 if (!FilterSpuriousWakeups) break; // previous semantics 4232 if (status == ETIMEDOUT) break; 4233 // We consume and ignore EINTR and spurious wakeups. 4234 } 4235 --_nParked; 4236 if (_Event >= 0) { 4237 ret = OS_OK; 4238 } 4239 _Event = 0; 4240 status = pthread_mutex_unlock(_mutex); 4241 assert_status(status == 0, status, "mutex_unlock"); 4242 assert(_nParked == 0, "invariant"); 4243 // Paranoia to ensure our locked and lock-free paths interact 4244 // correctly with each other. 4245 OrderAccess::fence(); 4246 return ret; 4247} 4248 4249void os::PlatformEvent::unpark() { 4250 // Transitions for _Event: 4251 // 0 => 1 : just return 4252 // 1 => 1 : just return 4253 // -1 => either 0 or 1; must signal target thread 4254 // That is, we can safely transition _Event from -1 to either 4255 // 0 or 1. 4256 // See also: "Semaphores in Plan 9" by Mullender & Cox 4257 // 4258 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4259 // that it will take two back-to-back park() calls for the owning 4260 // thread to block. This has the benefit of forcing a spurious return 4261 // from the first park() call after an unpark() call which will help 4262 // shake out uses of park() and unpark() without condition variables. 4263 4264 if (Atomic::xchg(1, &_Event) >= 0) return; 4265 4266 // Wait for the thread associated with the event to vacate 4267 int status = pthread_mutex_lock(_mutex); 4268 assert_status(status == 0, status, "mutex_lock"); 4269 int AnyWaiters = _nParked; 4270 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4271 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4272 AnyWaiters = 0; 4273 pthread_cond_signal(_cond); 4274 } 4275 status = pthread_mutex_unlock(_mutex); 4276 assert_status(status == 0, status, "mutex_unlock"); 4277 if (AnyWaiters != 0) { 4278 // Note that we signal() *after* dropping the lock for "immortal" Events. 4279 // This is safe and avoids a common class of futile wakeups. In rare 4280 // circumstances this can cause a thread to return prematurely from 4281 // cond_{timed}wait() but the spurious wakeup is benign and the victim 4282 // will simply re-test the condition and re-park itself. 4283 // This provides particular benefit if the underlying platform does not 4284 // provide wait morphing. 4285 status = pthread_cond_signal(_cond); 4286 assert_status(status == 0, status, "cond_signal"); 4287 } 4288} 4289 4290 4291// JSR166 4292// ------------------------------------------------------- 4293 4294// The solaris and bsd implementations of park/unpark are fairly 4295// conservative for now, but can be improved. They currently use a 4296// mutex/condvar pair, plus a a count. 4297// Park decrements count if > 0, else does a condvar wait. Unpark 4298// sets count to 1 and signals condvar. Only one thread ever waits 4299// on the condvar. Contention seen when trying to park implies that someone 4300// is unparking you, so don't wait. And spurious returns are fine, so there 4301// is no need to track notifications. 4302 4303#define MAX_SECS 100000000 4304 4305// This code is common to bsd and solaris and will be moved to a 4306// common place in dolphin. 4307// 4308// The passed in time value is either a relative time in nanoseconds 4309// or an absolute time in milliseconds. Either way it has to be unpacked 4310// into suitable seconds and nanoseconds components and stored in the 4311// given timespec structure. 4312// Given time is a 64-bit value and the time_t used in the timespec is only 4313// a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4314// overflow if times way in the future are given. Further on Solaris versions 4315// prior to 10 there is a restriction (see cond_timedwait) that the specified 4316// number of seconds, in abstime, is less than current_time + 100,000,000. 4317// As it will be 28 years before "now + 100000000" will overflow we can 4318// ignore overflow and just impose a hard-limit on seconds using the value 4319// of "now + 100,000,000". This places a limit on the timeout of about 3.17 4320// years from "now". 4321 4322static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4323 assert(time > 0, "convertTime"); 4324 4325 struct timeval now; 4326 int status = gettimeofday(&now, NULL); 4327 assert(status == 0, "gettimeofday"); 4328 4329 time_t max_secs = now.tv_sec + MAX_SECS; 4330 4331 if (isAbsolute) { 4332 jlong secs = time / 1000; 4333 if (secs > max_secs) { 4334 absTime->tv_sec = max_secs; 4335 } else { 4336 absTime->tv_sec = secs; 4337 } 4338 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4339 } else { 4340 jlong secs = time / NANOSECS_PER_SEC; 4341 if (secs >= MAX_SECS) { 4342 absTime->tv_sec = max_secs; 4343 absTime->tv_nsec = 0; 4344 } else { 4345 absTime->tv_sec = now.tv_sec + secs; 4346 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4347 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4348 absTime->tv_nsec -= NANOSECS_PER_SEC; 4349 ++absTime->tv_sec; // note: this must be <= max_secs 4350 } 4351 } 4352 } 4353 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4354 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4355 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4356 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4357} 4358 4359void Parker::park(bool isAbsolute, jlong time) { 4360 // Ideally we'd do something useful while spinning, such 4361 // as calling unpackTime(). 4362 4363 // Optional fast-path check: 4364 // Return immediately if a permit is available. 4365 // We depend on Atomic::xchg() having full barrier semantics 4366 // since we are doing a lock-free update to _counter. 4367 if (Atomic::xchg(0, &_counter) > 0) return; 4368 4369 Thread* thread = Thread::current(); 4370 assert(thread->is_Java_thread(), "Must be JavaThread"); 4371 JavaThread *jt = (JavaThread *)thread; 4372 4373 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4374 // Check interrupt before trying to wait 4375 if (Thread::is_interrupted(thread, false)) { 4376 return; 4377 } 4378 4379 // Next, demultiplex/decode time arguments 4380 struct timespec absTime; 4381 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4382 return; 4383 } 4384 if (time > 0) { 4385 unpackTime(&absTime, isAbsolute, time); 4386 } 4387 4388 4389 // Enter safepoint region 4390 // Beware of deadlocks such as 6317397. 4391 // The per-thread Parker:: mutex is a classic leaf-lock. 4392 // In particular a thread must never block on the Threads_lock while 4393 // holding the Parker:: mutex. If safepoints are pending both the 4394 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4395 ThreadBlockInVM tbivm(jt); 4396 4397 // Don't wait if cannot get lock since interference arises from 4398 // unblocking. Also. check interrupt before trying wait 4399 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4400 return; 4401 } 4402 4403 int status; 4404 if (_counter > 0) { // no wait needed 4405 _counter = 0; 4406 status = pthread_mutex_unlock(_mutex); 4407 assert(status == 0, "invariant"); 4408 // Paranoia to ensure our locked and lock-free paths interact 4409 // correctly with each other and Java-level accesses. 4410 OrderAccess::fence(); 4411 return; 4412 } 4413 4414#ifdef ASSERT 4415 // Don't catch signals while blocked; let the running threads have the signals. 4416 // (This allows a debugger to break into the running thread.) 4417 sigset_t oldsigs; 4418 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4419 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4420#endif 4421 4422 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4423 jt->set_suspend_equivalent(); 4424 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4425 4426 if (time == 0) { 4427 status = pthread_cond_wait(_cond, _mutex); 4428 } else { 4429 status = pthread_cond_timedwait(_cond, _mutex, &absTime); 4430 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4431 pthread_cond_destroy(_cond); 4432 pthread_cond_init(_cond, NULL); 4433 } 4434 } 4435 assert_status(status == 0 || status == EINTR || 4436 status == ETIMEDOUT, 4437 status, "cond_timedwait"); 4438 4439#ifdef ASSERT 4440 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4441#endif 4442 4443 _counter = 0; 4444 status = pthread_mutex_unlock(_mutex); 4445 assert_status(status == 0, status, "invariant"); 4446 // Paranoia to ensure our locked and lock-free paths interact 4447 // correctly with each other and Java-level accesses. 4448 OrderAccess::fence(); 4449 4450 // If externally suspended while waiting, re-suspend 4451 if (jt->handle_special_suspend_equivalent_condition()) { 4452 jt->java_suspend_self(); 4453 } 4454} 4455 4456void Parker::unpark() { 4457 int status = pthread_mutex_lock(_mutex); 4458 assert(status == 0, "invariant"); 4459 const int s = _counter; 4460 _counter = 1; 4461 if (s < 1) { 4462 if (WorkAroundNPTLTimedWaitHang) { 4463 status = pthread_cond_signal(_cond); 4464 assert(status == 0, "invariant"); 4465 status = pthread_mutex_unlock(_mutex); 4466 assert(status == 0, "invariant"); 4467 } else { 4468 status = pthread_mutex_unlock(_mutex); 4469 assert(status == 0, "invariant"); 4470 status = pthread_cond_signal(_cond); 4471 assert(status == 0, "invariant"); 4472 } 4473 } else { 4474 pthread_mutex_unlock(_mutex); 4475 assert(status == 0, "invariant"); 4476 } 4477} 4478 4479 4480// Darwin has no "environ" in a dynamic library. 4481#ifdef __APPLE__ 4482 #include <crt_externs.h> 4483 #define environ (*_NSGetEnviron()) 4484#else 4485extern char** environ; 4486#endif 4487 4488// Run the specified command in a separate process. Return its exit value, 4489// or -1 on failure (e.g. can't fork a new process). 4490// Unlike system(), this function can be called from signal handler. It 4491// doesn't block SIGINT et al. 4492int os::fork_and_exec(char* cmd) { 4493 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4494 4495 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4496 // pthread_atfork handlers and reset pthread library. All we need is a 4497 // separate process to execve. Make a direct syscall to fork process. 4498 // On IA64 there's no fork syscall, we have to use fork() and hope for 4499 // the best... 4500 pid_t pid = fork(); 4501 4502 if (pid < 0) { 4503 // fork failed 4504 return -1; 4505 4506 } else if (pid == 0) { 4507 // child process 4508 4509 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4510 // first to kill every thread on the thread list. Because this list is 4511 // not reset by fork() (see notes above), execve() will instead kill 4512 // every thread in the parent process. We know this is the only thread 4513 // in the new process, so make a system call directly. 4514 // IA64 should use normal execve() from glibc to match the glibc fork() 4515 // above. 4516 execve("/bin/sh", (char* const*)argv, environ); 4517 4518 // execve failed 4519 _exit(-1); 4520 4521 } else { 4522 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4523 // care about the actual exit code, for now. 4524 4525 int status; 4526 4527 // Wait for the child process to exit. This returns immediately if 4528 // the child has already exited. */ 4529 while (waitpid(pid, &status, 0) < 0) { 4530 switch (errno) { 4531 case ECHILD: return 0; 4532 case EINTR: break; 4533 default: return -1; 4534 } 4535 } 4536 4537 if (WIFEXITED(status)) { 4538 // The child exited normally; get its exit code. 4539 return WEXITSTATUS(status); 4540 } else if (WIFSIGNALED(status)) { 4541 // The child exited because of a signal 4542 // The best value to return is 0x80 + signal number, 4543 // because that is what all Unix shells do, and because 4544 // it allows callers to distinguish between process exit and 4545 // process death by signal. 4546 return 0x80 + WTERMSIG(status); 4547 } else { 4548 // Unknown exit code; pass it through 4549 return status; 4550 } 4551 } 4552} 4553 4554// is_headless_jre() 4555// 4556// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4557// in order to report if we are running in a headless jre 4558// 4559// Since JDK8 xawt/libmawt.so was moved into the same directory 4560// as libawt.so, and renamed libawt_xawt.so 4561// 4562bool os::is_headless_jre() { 4563#ifdef __APPLE__ 4564 // We no longer build headless-only on Mac OS X 4565 return false; 4566#else 4567 struct stat statbuf; 4568 char buf[MAXPATHLEN]; 4569 char libmawtpath[MAXPATHLEN]; 4570 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4571 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4572 char *p; 4573 4574 // Get path to libjvm.so 4575 os::jvm_path(buf, sizeof(buf)); 4576 4577 // Get rid of libjvm.so 4578 p = strrchr(buf, '/'); 4579 if (p == NULL) { 4580 return false; 4581 } else { 4582 *p = '\0'; 4583 } 4584 4585 // Get rid of client or server 4586 p = strrchr(buf, '/'); 4587 if (p == NULL) { 4588 return false; 4589 } else { 4590 *p = '\0'; 4591 } 4592 4593 // check xawt/libmawt.so 4594 strcpy(libmawtpath, buf); 4595 strcat(libmawtpath, xawtstr); 4596 if (::stat(libmawtpath, &statbuf) == 0) return false; 4597 4598 // check libawt_xawt.so 4599 strcpy(libmawtpath, buf); 4600 strcat(libmawtpath, new_xawtstr); 4601 if (::stat(libmawtpath, &statbuf) == 0) return false; 4602 4603 return true; 4604#endif 4605} 4606 4607// Get the default path to the core file 4608// Returns the length of the string 4609int os::get_core_path(char* buffer, size_t bufferSize) { 4610 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id()); 4611 4612 // Truncate if theoretical string was longer than bufferSize 4613 n = MIN2(n, (int)bufferSize); 4614 4615 return n; 4616} 4617 4618#ifndef PRODUCT 4619void TestReserveMemorySpecial_test() { 4620 // No tests available for this platform 4621} 4622#endif 4623 4624bool os::start_debugging(char *buf, int buflen) { 4625 int len = (int)strlen(buf); 4626 char *p = &buf[len]; 4627 4628 jio_snprintf(p, buflen-len, 4629 "\n\n" 4630 "Do you want to debug the problem?\n\n" 4631 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n" 4632 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n" 4633 "Otherwise, press RETURN to abort...", 4634 os::current_process_id(), os::current_process_id(), 4635 os::current_thread_id(), os::current_thread_id()); 4636 4637 bool yes = os::message_box("Unexpected Error", buf); 4638 4639 if (yes) { 4640 // yes, user asked VM to launch debugger 4641 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d", 4642 os::current_process_id(), os::current_process_id()); 4643 4644 os::fork_and_exec(buf); 4645 yes = false; 4646 } 4647 return yes; 4648} 4649