os_bsd.cpp revision 7060:32b18c8f19fa
1/* 2 * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25// no precompiled headers 26#include "classfile/classLoader.hpp" 27#include "classfile/systemDictionary.hpp" 28#include "classfile/vmSymbols.hpp" 29#include "code/icBuffer.hpp" 30#include "code/vtableStubs.hpp" 31#include "compiler/compileBroker.hpp" 32#include "compiler/disassembler.hpp" 33#include "interpreter/interpreter.hpp" 34#include "jvm_bsd.h" 35#include "memory/allocation.inline.hpp" 36#include "memory/filemap.hpp" 37#include "mutex_bsd.inline.hpp" 38#include "oops/oop.inline.hpp" 39#include "os_bsd.inline.hpp" 40#include "os_share_bsd.hpp" 41#include "prims/jniFastGetField.hpp" 42#include "prims/jvm.h" 43#include "prims/jvm_misc.hpp" 44#include "runtime/arguments.hpp" 45#include "runtime/atomic.inline.hpp" 46#include "runtime/extendedPC.hpp" 47#include "runtime/globals.hpp" 48#include "runtime/interfaceSupport.hpp" 49#include "runtime/java.hpp" 50#include "runtime/javaCalls.hpp" 51#include "runtime/mutexLocker.hpp" 52#include "runtime/objectMonitor.hpp" 53#include "runtime/orderAccess.inline.hpp" 54#include "runtime/osThread.hpp" 55#include "runtime/perfMemory.hpp" 56#include "runtime/sharedRuntime.hpp" 57#include "runtime/statSampler.hpp" 58#include "runtime/stubRoutines.hpp" 59#include "runtime/thread.inline.hpp" 60#include "runtime/threadCritical.hpp" 61#include "runtime/timer.hpp" 62#include "services/attachListener.hpp" 63#include "services/memTracker.hpp" 64#include "services/runtimeService.hpp" 65#include "utilities/decoder.hpp" 66#include "utilities/defaultStream.hpp" 67#include "utilities/events.hpp" 68#include "utilities/growableArray.hpp" 69#include "utilities/vmError.hpp" 70 71// put OS-includes here 72# include <sys/types.h> 73# include <sys/mman.h> 74# include <sys/stat.h> 75# include <sys/select.h> 76# include <pthread.h> 77# include <signal.h> 78# include <errno.h> 79# include <dlfcn.h> 80# include <stdio.h> 81# include <unistd.h> 82# include <sys/resource.h> 83# include <pthread.h> 84# include <sys/stat.h> 85# include <sys/time.h> 86# include <sys/times.h> 87# include <sys/utsname.h> 88# include <sys/socket.h> 89# include <sys/wait.h> 90# include <time.h> 91# include <pwd.h> 92# include <poll.h> 93# include <semaphore.h> 94# include <fcntl.h> 95# include <string.h> 96# include <sys/param.h> 97# include <sys/sysctl.h> 98# include <sys/ipc.h> 99# include <sys/shm.h> 100#ifndef __APPLE__ 101# include <link.h> 102#endif 103# include <stdint.h> 104# include <inttypes.h> 105# include <sys/ioctl.h> 106# include <sys/syscall.h> 107 108#if defined(__FreeBSD__) || defined(__NetBSD__) 109# include <elf.h> 110#endif 111 112#ifdef __APPLE__ 113# include <mach/mach.h> // semaphore_* API 114# include <mach-o/dyld.h> 115# include <sys/proc_info.h> 116# include <objc/objc-auto.h> 117#endif 118 119#ifndef MAP_ANONYMOUS 120#define MAP_ANONYMOUS MAP_ANON 121#endif 122 123#define MAX_PATH (2 * K) 124 125// for timer info max values which include all bits 126#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 127 128#define LARGEPAGES_BIT (1 << 6) 129 130PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 131 132//////////////////////////////////////////////////////////////////////////////// 133// global variables 134julong os::Bsd::_physical_memory = 0; 135 136#ifdef __APPLE__ 137mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; 138volatile uint64_t os::Bsd::_max_abstime = 0; 139#else 140int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 141#endif 142pthread_t os::Bsd::_main_thread; 143int os::Bsd::_page_size = -1; 144 145static jlong initial_time_count=0; 146 147static int clock_tics_per_sec = 100; 148 149// For diagnostics to print a message once. see run_periodic_checks 150static sigset_t check_signal_done; 151static bool check_signals = true; 152 153static pid_t _initial_pid = 0; 154 155/* Signal number used to suspend/resume a thread */ 156 157/* do not use any signal number less than SIGSEGV, see 4355769 */ 158static int SR_signum = SIGUSR2; 159sigset_t SR_sigset; 160 161 162//////////////////////////////////////////////////////////////////////////////// 163// utility functions 164 165static int SR_initialize(); 166static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); 167 168julong os::available_memory() { 169 return Bsd::available_memory(); 170} 171 172// available here means free 173julong os::Bsd::available_memory() { 174 uint64_t available = physical_memory() >> 2; 175#ifdef __APPLE__ 176 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; 177 vm_statistics64_data_t vmstat; 178 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, 179 (host_info64_t)&vmstat, &count); 180 assert(kerr == KERN_SUCCESS, 181 "host_statistics64 failed - check mach_host_self() and count"); 182 if (kerr == KERN_SUCCESS) { 183 available = vmstat.free_count * os::vm_page_size(); 184 } 185#endif 186 return available; 187} 188 189julong os::physical_memory() { 190 return Bsd::physical_memory(); 191} 192 193//////////////////////////////////////////////////////////////////////////////// 194// environment support 195 196bool os::getenv(const char* name, char* buf, int len) { 197 const char* val = ::getenv(name); 198 if (val != NULL && strlen(val) < (size_t)len) { 199 strcpy(buf, val); 200 return true; 201 } 202 if (len > 0) buf[0] = 0; // return a null string 203 return false; 204} 205 206 207// Return true if user is running as root. 208 209bool os::have_special_privileges() { 210 static bool init = false; 211 static bool privileges = false; 212 if (!init) { 213 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 214 init = true; 215 } 216 return privileges; 217} 218 219 220 221// Cpu architecture string 222#if defined(ZERO) 223static char cpu_arch[] = ZERO_LIBARCH; 224#elif defined(IA64) 225static char cpu_arch[] = "ia64"; 226#elif defined(IA32) 227static char cpu_arch[] = "i386"; 228#elif defined(AMD64) 229static char cpu_arch[] = "amd64"; 230#elif defined(ARM) 231static char cpu_arch[] = "arm"; 232#elif defined(PPC32) 233static char cpu_arch[] = "ppc"; 234#elif defined(SPARC) 235# ifdef _LP64 236static char cpu_arch[] = "sparcv9"; 237# else 238static char cpu_arch[] = "sparc"; 239# endif 240#else 241#error Add appropriate cpu_arch setting 242#endif 243 244// Compiler variant 245#ifdef COMPILER2 246#define COMPILER_VARIANT "server" 247#else 248#define COMPILER_VARIANT "client" 249#endif 250 251 252void os::Bsd::initialize_system_info() { 253 int mib[2]; 254 size_t len; 255 int cpu_val; 256 julong mem_val; 257 258 /* get processors count via hw.ncpus sysctl */ 259 mib[0] = CTL_HW; 260 mib[1] = HW_NCPU; 261 len = sizeof(cpu_val); 262 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 263 assert(len == sizeof(cpu_val), "unexpected data size"); 264 set_processor_count(cpu_val); 265 } 266 else { 267 set_processor_count(1); // fallback 268 } 269 270 /* get physical memory via hw.memsize sysctl (hw.memsize is used 271 * since it returns a 64 bit value) 272 */ 273 mib[0] = CTL_HW; 274 275#if defined (HW_MEMSIZE) // Apple 276 mib[1] = HW_MEMSIZE; 277#elif defined(HW_PHYSMEM) // Most of BSD 278 mib[1] = HW_PHYSMEM; 279#elif defined(HW_REALMEM) // Old FreeBSD 280 mib[1] = HW_REALMEM; 281#else 282 #error No ways to get physmem 283#endif 284 285 len = sizeof(mem_val); 286 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { 287 assert(len == sizeof(mem_val), "unexpected data size"); 288 _physical_memory = mem_val; 289 } else { 290 _physical_memory = 256*1024*1024; // fallback (XXXBSD?) 291 } 292 293#ifdef __OpenBSD__ 294 { 295 // limit _physical_memory memory view on OpenBSD since 296 // datasize rlimit restricts us anyway. 297 struct rlimit limits; 298 getrlimit(RLIMIT_DATA, &limits); 299 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 300 } 301#endif 302} 303 304#ifdef __APPLE__ 305static const char *get_home() { 306 const char *home_dir = ::getenv("HOME"); 307 if ((home_dir == NULL) || (*home_dir == '\0')) { 308 struct passwd *passwd_info = getpwuid(geteuid()); 309 if (passwd_info != NULL) { 310 home_dir = passwd_info->pw_dir; 311 } 312 } 313 314 return home_dir; 315} 316#endif 317 318void os::init_system_properties_values() { 319 // The next steps are taken in the product version: 320 // 321 // Obtain the JAVA_HOME value from the location of libjvm.so. 322 // This library should be located at: 323 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so. 324 // 325 // If "/jre/lib/" appears at the right place in the path, then we 326 // assume libjvm.so is installed in a JDK and we use this path. 327 // 328 // Otherwise exit with message: "Could not create the Java virtual machine." 329 // 330 // The following extra steps are taken in the debugging version: 331 // 332 // If "/jre/lib/" does NOT appear at the right place in the path 333 // instead of exit check for $JAVA_HOME environment variable. 334 // 335 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 336 // then we append a fake suffix "hotspot/libjvm.so" to this path so 337 // it looks like libjvm.so is installed there 338 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so. 339 // 340 // Otherwise exit. 341 // 342 // Important note: if the location of libjvm.so changes this 343 // code needs to be changed accordingly. 344 345// See ld(1): 346// The linker uses the following search paths to locate required 347// shared libraries: 348// 1: ... 349// ... 350// 7: The default directories, normally /lib and /usr/lib. 351#ifndef DEFAULT_LIBPATH 352#define DEFAULT_LIBPATH "/lib:/usr/lib" 353#endif 354 355// Base path of extensions installed on the system. 356#define SYS_EXT_DIR "/usr/java/packages" 357#define EXTENSIONS_DIR "/lib/ext" 358#define ENDORSED_DIR "/lib/endorsed" 359 360#ifndef __APPLE__ 361 362 // Buffer that fits several sprintfs. 363 // Note that the space for the colon and the trailing null are provided 364 // by the nulls included by the sizeof operator. 365 const size_t bufsize = 366 MAX3((size_t)MAXPATHLEN, // For dll_dir & friends. 367 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir 368 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir 369 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 370 371 // sysclasspath, java_home, dll_dir 372 { 373 char *pslash; 374 os::jvm_path(buf, bufsize); 375 376 // Found the full path to libjvm.so. 377 // Now cut the path to <java_home>/jre if we can. 378 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 379 pslash = strrchr(buf, '/'); 380 if (pslash != NULL) { 381 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 382 } 383 Arguments::set_dll_dir(buf); 384 385 if (pslash != NULL) { 386 pslash = strrchr(buf, '/'); 387 if (pslash != NULL) { 388 *pslash = '\0'; // Get rid of /<arch>. 389 pslash = strrchr(buf, '/'); 390 if (pslash != NULL) { 391 *pslash = '\0'; // Get rid of /lib. 392 } 393 } 394 } 395 Arguments::set_java_home(buf); 396 set_boot_path('/', ':'); 397 } 398 399 // Where to look for native libraries. 400 // 401 // Note: Due to a legacy implementation, most of the library path 402 // is set in the launcher. This was to accomodate linking restrictions 403 // on legacy Bsd implementations (which are no longer supported). 404 // Eventually, all the library path setting will be done here. 405 // 406 // However, to prevent the proliferation of improperly built native 407 // libraries, the new path component /usr/java/packages is added here. 408 // Eventually, all the library path setting will be done here. 409 { 410 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 411 // should always exist (until the legacy problem cited above is 412 // addressed). 413 const char *v = ::getenv("LD_LIBRARY_PATH"); 414 const char *v_colon = ":"; 415 if (v == NULL) { v = ""; v_colon = ""; } 416 // That's +1 for the colon and +1 for the trailing '\0'. 417 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 418 strlen(v) + 1 + 419 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, 420 mtInternal); 421 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); 422 Arguments::set_library_path(ld_library_path); 423 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); 424 } 425 426 // Extensions directories. 427 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); 428 Arguments::set_ext_dirs(buf); 429 430 // Endorsed standards default directory. 431 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 432 Arguments::set_endorsed_dirs(buf); 433 434 FREE_C_HEAP_ARRAY(char, buf, mtInternal); 435 436#else // __APPLE__ 437 438#define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 439#define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 440 441 const char *user_home_dir = get_home(); 442 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. 443 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 444 sizeof(SYS_EXTENSIONS_DIRS); 445 446 // Buffer that fits several sprintfs. 447 // Note that the space for the colon and the trailing null are provided 448 // by the nulls included by the sizeof operator. 449 const size_t bufsize = 450 MAX3((size_t)MAXPATHLEN, // for dll_dir & friends. 451 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir 452 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir 453 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); 454 455 // sysclasspath, java_home, dll_dir 456 { 457 char *pslash; 458 os::jvm_path(buf, bufsize); 459 460 // Found the full path to libjvm.so. 461 // Now cut the path to <java_home>/jre if we can. 462 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. 463 pslash = strrchr(buf, '/'); 464 if (pslash != NULL) { 465 *pslash = '\0'; // Get rid of /{client|server|hotspot}. 466 } 467 Arguments::set_dll_dir(buf); 468 469 if (pslash != NULL) { 470 pslash = strrchr(buf, '/'); 471 if (pslash != NULL) { 472 *pslash = '\0'; // Get rid of /lib. 473 } 474 } 475 Arguments::set_java_home(buf); 476 set_boot_path('/', ':'); 477 } 478 479 // Where to look for native libraries. 480 // 481 // Note: Due to a legacy implementation, most of the library path 482 // is set in the launcher. This was to accomodate linking restrictions 483 // on legacy Bsd implementations (which are no longer supported). 484 // Eventually, all the library path setting will be done here. 485 // 486 // However, to prevent the proliferation of improperly built native 487 // libraries, the new path component /usr/java/packages is added here. 488 // Eventually, all the library path setting will be done here. 489 { 490 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It 491 // should always exist (until the legacy problem cited above is 492 // addressed). 493 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code 494 // can specify a directory inside an app wrapper 495 const char *l = ::getenv("JAVA_LIBRARY_PATH"); 496 const char *l_colon = ":"; 497 if (l == NULL) { l = ""; l_colon = ""; } 498 499 const char *v = ::getenv("DYLD_LIBRARY_PATH"); 500 const char *v_colon = ":"; 501 if (v == NULL) { v = ""; v_colon = ""; } 502 503 // Apple's Java6 has "." at the beginning of java.library.path. 504 // OpenJDK on Windows has "." at the end of java.library.path. 505 // OpenJDK on Linux and Solaris don't have "." in java.library.path 506 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 507 // "." is appended to the end of java.library.path. Yes, this 508 // could cause a change in behavior, but Apple's Java6 behavior 509 // can be achieved by putting "." at the beginning of the 510 // JAVA_LIBRARY_PATH environment variable. 511 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, 512 strlen(v) + 1 + strlen(l) + 1 + 513 system_ext_size + 3, 514 mtInternal); 515 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", 516 v, v_colon, l, l_colon, user_home_dir); 517 Arguments::set_library_path(ld_library_path); 518 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); 519 } 520 521 // Extensions directories. 522 // 523 // Note that the space for the colon and the trailing null are provided 524 // by the nulls included by the sizeof operator (so actually one byte more 525 // than necessary is allocated). 526 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, 527 user_home_dir, Arguments::get_java_home()); 528 Arguments::set_ext_dirs(buf); 529 530 // Endorsed standards default directory. 531 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 532 Arguments::set_endorsed_dirs(buf); 533 534 FREE_C_HEAP_ARRAY(char, buf, mtInternal); 535 536#undef SYS_EXTENSIONS_DIR 537#undef SYS_EXTENSIONS_DIRS 538 539#endif // __APPLE__ 540 541#undef SYS_EXT_DIR 542#undef EXTENSIONS_DIR 543#undef ENDORSED_DIR 544} 545 546//////////////////////////////////////////////////////////////////////////////// 547// breakpoint support 548 549void os::breakpoint() { 550 BREAKPOINT; 551} 552 553extern "C" void breakpoint() { 554 // use debugger to set breakpoint here 555} 556 557//////////////////////////////////////////////////////////////////////////////// 558// signal support 559 560debug_only(static bool signal_sets_initialized = false); 561static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 562 563bool os::Bsd::is_sig_ignored(int sig) { 564 struct sigaction oact; 565 sigaction(sig, (struct sigaction*)NULL, &oact); 566 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 567 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 568 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 569 return true; 570 else 571 return false; 572} 573 574void os::Bsd::signal_sets_init() { 575 // Should also have an assertion stating we are still single-threaded. 576 assert(!signal_sets_initialized, "Already initialized"); 577 // Fill in signals that are necessarily unblocked for all threads in 578 // the VM. Currently, we unblock the following signals: 579 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 580 // by -Xrs (=ReduceSignalUsage)); 581 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 582 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 583 // the dispositions or masks wrt these signals. 584 // Programs embedding the VM that want to use the above signals for their 585 // own purposes must, at this time, use the "-Xrs" option to prevent 586 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 587 // (See bug 4345157, and other related bugs). 588 // In reality, though, unblocking these signals is really a nop, since 589 // these signals are not blocked by default. 590 sigemptyset(&unblocked_sigs); 591 sigemptyset(&allowdebug_blocked_sigs); 592 sigaddset(&unblocked_sigs, SIGILL); 593 sigaddset(&unblocked_sigs, SIGSEGV); 594 sigaddset(&unblocked_sigs, SIGBUS); 595 sigaddset(&unblocked_sigs, SIGFPE); 596 sigaddset(&unblocked_sigs, SR_signum); 597 598 if (!ReduceSignalUsage) { 599 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 600 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 601 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 602 } 603 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 604 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 605 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 606 } 607 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 608 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 609 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 610 } 611 } 612 // Fill in signals that are blocked by all but the VM thread. 613 sigemptyset(&vm_sigs); 614 if (!ReduceSignalUsage) 615 sigaddset(&vm_sigs, BREAK_SIGNAL); 616 debug_only(signal_sets_initialized = true); 617 618} 619 620// These are signals that are unblocked while a thread is running Java. 621// (For some reason, they get blocked by default.) 622sigset_t* os::Bsd::unblocked_signals() { 623 assert(signal_sets_initialized, "Not initialized"); 624 return &unblocked_sigs; 625} 626 627// These are the signals that are blocked while a (non-VM) thread is 628// running Java. Only the VM thread handles these signals. 629sigset_t* os::Bsd::vm_signals() { 630 assert(signal_sets_initialized, "Not initialized"); 631 return &vm_sigs; 632} 633 634// These are signals that are blocked during cond_wait to allow debugger in 635sigset_t* os::Bsd::allowdebug_blocked_signals() { 636 assert(signal_sets_initialized, "Not initialized"); 637 return &allowdebug_blocked_sigs; 638} 639 640void os::Bsd::hotspot_sigmask(Thread* thread) { 641 642 //Save caller's signal mask before setting VM signal mask 643 sigset_t caller_sigmask; 644 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 645 646 OSThread* osthread = thread->osthread(); 647 osthread->set_caller_sigmask(caller_sigmask); 648 649 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 650 651 if (!ReduceSignalUsage) { 652 if (thread->is_VM_thread()) { 653 // Only the VM thread handles BREAK_SIGNAL ... 654 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 655 } else { 656 // ... all other threads block BREAK_SIGNAL 657 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 658 } 659 } 660} 661 662 663////////////////////////////////////////////////////////////////////////////// 664// create new thread 665 666// check if it's safe to start a new thread 667static bool _thread_safety_check(Thread* thread) { 668 return true; 669} 670 671#ifdef __APPLE__ 672// library handle for calling objc_registerThreadWithCollector() 673// without static linking to the libobjc library 674#define OBJC_LIB "/usr/lib/libobjc.dylib" 675#define OBJC_GCREGISTER "objc_registerThreadWithCollector" 676typedef void (*objc_registerThreadWithCollector_t)(); 677extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 678objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 679#endif 680 681#ifdef __APPLE__ 682static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { 683 // Additional thread_id used to correlate threads in SA 684 thread_identifier_info_data_t m_ident_info; 685 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; 686 687 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, 688 (thread_info_t) &m_ident_info, &count); 689 690 return m_ident_info.thread_id; 691} 692#endif 693 694// Thread start routine for all newly created threads 695static void *java_start(Thread *thread) { 696 // Try to randomize the cache line index of hot stack frames. 697 // This helps when threads of the same stack traces evict each other's 698 // cache lines. The threads can be either from the same JVM instance, or 699 // from different JVM instances. The benefit is especially true for 700 // processors with hyperthreading technology. 701 static int counter = 0; 702 int pid = os::current_process_id(); 703 alloca(((pid ^ counter++) & 7) * 128); 704 705 ThreadLocalStorage::set_thread(thread); 706 707 OSThread* osthread = thread->osthread(); 708 Monitor* sync = osthread->startThread_lock(); 709 710 // non floating stack BsdThreads needs extra check, see above 711 if (!_thread_safety_check(thread)) { 712 // notify parent thread 713 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 714 osthread->set_state(ZOMBIE); 715 sync->notify_all(); 716 return NULL; 717 } 718 719 osthread->set_thread_id(os::Bsd::gettid()); 720 721#ifdef __APPLE__ 722 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 723 guarantee(unique_thread_id != 0, "unique thread id was not found"); 724 osthread->set_unique_thread_id(unique_thread_id); 725#endif 726 // initialize signal mask for this thread 727 os::Bsd::hotspot_sigmask(thread); 728 729 // initialize floating point control register 730 os::Bsd::init_thread_fpu_state(); 731 732#ifdef __APPLE__ 733 // register thread with objc gc 734 if (objc_registerThreadWithCollectorFunction != NULL) { 735 objc_registerThreadWithCollectorFunction(); 736 } 737#endif 738 739 // handshaking with parent thread 740 { 741 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 742 743 // notify parent thread 744 osthread->set_state(INITIALIZED); 745 sync->notify_all(); 746 747 // wait until os::start_thread() 748 while (osthread->get_state() == INITIALIZED) { 749 sync->wait(Mutex::_no_safepoint_check_flag); 750 } 751 } 752 753 // call one more level start routine 754 thread->run(); 755 756 return 0; 757} 758 759bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 760 assert(thread->osthread() == NULL, "caller responsible"); 761 762 // Allocate the OSThread object 763 OSThread* osthread = new OSThread(NULL, NULL); 764 if (osthread == NULL) { 765 return false; 766 } 767 768 // set the correct thread state 769 osthread->set_thread_type(thr_type); 770 771 // Initial state is ALLOCATED but not INITIALIZED 772 osthread->set_state(ALLOCATED); 773 774 thread->set_osthread(osthread); 775 776 // init thread attributes 777 pthread_attr_t attr; 778 pthread_attr_init(&attr); 779 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 780 781 // stack size 782 if (os::Bsd::supports_variable_stack_size()) { 783 // calculate stack size if it's not specified by caller 784 if (stack_size == 0) { 785 stack_size = os::Bsd::default_stack_size(thr_type); 786 787 switch (thr_type) { 788 case os::java_thread: 789 // Java threads use ThreadStackSize which default value can be 790 // changed with the flag -Xss 791 assert(JavaThread::stack_size_at_create() > 0, "this should be set"); 792 stack_size = JavaThread::stack_size_at_create(); 793 break; 794 case os::compiler_thread: 795 if (CompilerThreadStackSize > 0) { 796 stack_size = (size_t)(CompilerThreadStackSize * K); 797 break; 798 } // else fall through: 799 // use VMThreadStackSize if CompilerThreadStackSize is not defined 800 case os::vm_thread: 801 case os::pgc_thread: 802 case os::cgc_thread: 803 case os::watcher_thread: 804 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 805 break; 806 } 807 } 808 809 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 810 pthread_attr_setstacksize(&attr, stack_size); 811 } else { 812 // let pthread_create() pick the default value. 813 } 814 815 ThreadState state; 816 817 { 818 pthread_t tid; 819 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 820 821 pthread_attr_destroy(&attr); 822 823 if (ret != 0) { 824 if (PrintMiscellaneous && (Verbose || WizardMode)) { 825 perror("pthread_create()"); 826 } 827 // Need to clean up stuff we've allocated so far 828 thread->set_osthread(NULL); 829 delete osthread; 830 return false; 831 } 832 833 // Store pthread info into the OSThread 834 osthread->set_pthread_id(tid); 835 836 // Wait until child thread is either initialized or aborted 837 { 838 Monitor* sync_with_child = osthread->startThread_lock(); 839 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 840 while ((state = osthread->get_state()) == ALLOCATED) { 841 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 842 } 843 } 844 845 } 846 847 // Aborted due to thread limit being reached 848 if (state == ZOMBIE) { 849 thread->set_osthread(NULL); 850 delete osthread; 851 return false; 852 } 853 854 // The thread is returned suspended (in state INITIALIZED), 855 // and is started higher up in the call chain 856 assert(state == INITIALIZED, "race condition"); 857 return true; 858} 859 860///////////////////////////////////////////////////////////////////////////// 861// attach existing thread 862 863// bootstrap the main thread 864bool os::create_main_thread(JavaThread* thread) { 865 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 866 return create_attached_thread(thread); 867} 868 869bool os::create_attached_thread(JavaThread* thread) { 870#ifdef ASSERT 871 thread->verify_not_published(); 872#endif 873 874 // Allocate the OSThread object 875 OSThread* osthread = new OSThread(NULL, NULL); 876 877 if (osthread == NULL) { 878 return false; 879 } 880 881 osthread->set_thread_id(os::Bsd::gettid()); 882 883 // Store pthread info into the OSThread 884#ifdef __APPLE__ 885 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); 886 guarantee(unique_thread_id != 0, "just checking"); 887 osthread->set_unique_thread_id(unique_thread_id); 888#endif 889 osthread->set_pthread_id(::pthread_self()); 890 891 // initialize floating point control register 892 os::Bsd::init_thread_fpu_state(); 893 894 // Initial thread state is RUNNABLE 895 osthread->set_state(RUNNABLE); 896 897 thread->set_osthread(osthread); 898 899 // initialize signal mask for this thread 900 // and save the caller's signal mask 901 os::Bsd::hotspot_sigmask(thread); 902 903 return true; 904} 905 906void os::pd_start_thread(Thread* thread) { 907 OSThread * osthread = thread->osthread(); 908 assert(osthread->get_state() != INITIALIZED, "just checking"); 909 Monitor* sync_with_child = osthread->startThread_lock(); 910 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 911 sync_with_child->notify(); 912} 913 914// Free Bsd resources related to the OSThread 915void os::free_thread(OSThread* osthread) { 916 assert(osthread != NULL, "osthread not set"); 917 918 if (Thread::current()->osthread() == osthread) { 919 // Restore caller's signal mask 920 sigset_t sigmask = osthread->caller_sigmask(); 921 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 922 } 923 924 delete osthread; 925} 926 927////////////////////////////////////////////////////////////////////////////// 928// thread local storage 929 930// Restore the thread pointer if the destructor is called. This is in case 931// someone from JNI code sets up a destructor with pthread_key_create to run 932// detachCurrentThread on thread death. Unless we restore the thread pointer we 933// will hang or crash. When detachCurrentThread is called the key will be set 934// to null and we will not be called again. If detachCurrentThread is never 935// called we could loop forever depending on the pthread implementation. 936static void restore_thread_pointer(void* p) { 937 Thread* thread = (Thread*) p; 938 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread); 939} 940 941int os::allocate_thread_local_storage() { 942 pthread_key_t key; 943 int rslt = pthread_key_create(&key, restore_thread_pointer); 944 assert(rslt == 0, "cannot allocate thread local storage"); 945 return (int)key; 946} 947 948// Note: This is currently not used by VM, as we don't destroy TLS key 949// on VM exit. 950void os::free_thread_local_storage(int index) { 951 int rslt = pthread_key_delete((pthread_key_t)index); 952 assert(rslt == 0, "invalid index"); 953} 954 955void os::thread_local_storage_at_put(int index, void* value) { 956 int rslt = pthread_setspecific((pthread_key_t)index, value); 957 assert(rslt == 0, "pthread_setspecific failed"); 958} 959 960extern "C" Thread* get_thread() { 961 return ThreadLocalStorage::thread(); 962} 963 964 965//////////////////////////////////////////////////////////////////////////////// 966// time support 967 968// Time since start-up in seconds to a fine granularity. 969// Used by VMSelfDestructTimer and the MemProfiler. 970double os::elapsedTime() { 971 972 return ((double)os::elapsed_counter()) / os::elapsed_frequency(); 973} 974 975jlong os::elapsed_counter() { 976 return javaTimeNanos() - initial_time_count; 977} 978 979jlong os::elapsed_frequency() { 980 return NANOSECS_PER_SEC; // nanosecond resolution 981} 982 983bool os::supports_vtime() { return true; } 984bool os::enable_vtime() { return false; } 985bool os::vtime_enabled() { return false; } 986 987double os::elapsedVTime() { 988 // better than nothing, but not much 989 return elapsedTime(); 990} 991 992jlong os::javaTimeMillis() { 993 timeval time; 994 int status = gettimeofday(&time, NULL); 995 assert(status != -1, "bsd error"); 996 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 997} 998 999#ifndef __APPLE__ 1000#ifndef CLOCK_MONOTONIC 1001#define CLOCK_MONOTONIC (1) 1002#endif 1003#endif 1004 1005#ifdef __APPLE__ 1006void os::Bsd::clock_init() { 1007 mach_timebase_info(&_timebase_info); 1008} 1009#else 1010void os::Bsd::clock_init() { 1011 struct timespec res; 1012 struct timespec tp; 1013 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 1014 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 1015 // yes, monotonic clock is supported 1016 _clock_gettime = ::clock_gettime; 1017 } 1018} 1019#endif 1020 1021 1022 1023#ifdef __APPLE__ 1024 1025jlong os::javaTimeNanos() { 1026 const uint64_t tm = mach_absolute_time(); 1027 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; 1028 const uint64_t prev = Bsd::_max_abstime; 1029 if (now <= prev) { 1030 return prev; // same or retrograde time; 1031 } 1032 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); 1033 assert(obsv >= prev, "invariant"); // Monotonicity 1034 // If the CAS succeeded then we're done and return "now". 1035 // If the CAS failed and the observed value "obsv" is >= now then 1036 // we should return "obsv". If the CAS failed and now > obsv > prv then 1037 // some other thread raced this thread and installed a new value, in which case 1038 // we could either (a) retry the entire operation, (b) retry trying to install now 1039 // or (c) just return obsv. We use (c). No loop is required although in some cases 1040 // we might discard a higher "now" value in deference to a slightly lower but freshly 1041 // installed obsv value. That's entirely benign -- it admits no new orderings compared 1042 // to (a) or (b) -- and greatly reduces coherence traffic. 1043 // We might also condition (c) on the magnitude of the delta between obsv and now. 1044 // Avoiding excessive CAS operations to hot RW locations is critical. 1045 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate 1046 return (prev == obsv) ? now : obsv; 1047} 1048 1049#else // __APPLE__ 1050 1051jlong os::javaTimeNanos() { 1052 if (os::supports_monotonic_clock()) { 1053 struct timespec tp; 1054 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); 1055 assert(status == 0, "gettime error"); 1056 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1057 return result; 1058 } else { 1059 timeval time; 1060 int status = gettimeofday(&time, NULL); 1061 assert(status != -1, "bsd error"); 1062 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1063 return 1000 * usecs; 1064 } 1065} 1066 1067#endif // __APPLE__ 1068 1069void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1070 if (os::supports_monotonic_clock()) { 1071 info_ptr->max_value = ALL_64_BITS; 1072 1073 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1074 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1075 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1076 } else { 1077 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1078 info_ptr->max_value = ALL_64_BITS; 1079 1080 // gettimeofday is a real time clock so it skips 1081 info_ptr->may_skip_backward = true; 1082 info_ptr->may_skip_forward = true; 1083 } 1084 1085 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1086} 1087 1088// Return the real, user, and system times in seconds from an 1089// arbitrary fixed point in the past. 1090bool os::getTimesSecs(double* process_real_time, 1091 double* process_user_time, 1092 double* process_system_time) { 1093 struct tms ticks; 1094 clock_t real_ticks = times(&ticks); 1095 1096 if (real_ticks == (clock_t) (-1)) { 1097 return false; 1098 } else { 1099 double ticks_per_second = (double) clock_tics_per_sec; 1100 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1101 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1102 *process_real_time = ((double) real_ticks) / ticks_per_second; 1103 1104 return true; 1105 } 1106} 1107 1108 1109char * os::local_time_string(char *buf, size_t buflen) { 1110 struct tm t; 1111 time_t long_time; 1112 time(&long_time); 1113 localtime_r(&long_time, &t); 1114 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1115 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1116 t.tm_hour, t.tm_min, t.tm_sec); 1117 return buf; 1118} 1119 1120struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1121 return localtime_r(clock, res); 1122} 1123 1124//////////////////////////////////////////////////////////////////////////////// 1125// runtime exit support 1126 1127// Note: os::shutdown() might be called very early during initialization, or 1128// called from signal handler. Before adding something to os::shutdown(), make 1129// sure it is async-safe and can handle partially initialized VM. 1130void os::shutdown() { 1131 1132 // allow PerfMemory to attempt cleanup of any persistent resources 1133 perfMemory_exit(); 1134 1135 // needs to remove object in file system 1136 AttachListener::abort(); 1137 1138 // flush buffered output, finish log files 1139 ostream_abort(); 1140 1141 // Check for abort hook 1142 abort_hook_t abort_hook = Arguments::abort_hook(); 1143 if (abort_hook != NULL) { 1144 abort_hook(); 1145 } 1146 1147} 1148 1149// Note: os::abort() might be called very early during initialization, or 1150// called from signal handler. Before adding something to os::abort(), make 1151// sure it is async-safe and can handle partially initialized VM. 1152void os::abort(bool dump_core) { 1153 os::shutdown(); 1154 if (dump_core) { 1155#ifndef PRODUCT 1156 fdStream out(defaultStream::output_fd()); 1157 out.print_raw("Current thread is "); 1158 char buf[16]; 1159 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1160 out.print_raw_cr(buf); 1161 out.print_raw_cr("Dumping core ..."); 1162#endif 1163 ::abort(); // dump core 1164 } 1165 1166 ::exit(1); 1167} 1168 1169// Die immediately, no exit hook, no abort hook, no cleanup. 1170void os::die() { 1171 // _exit() on BsdThreads only kills current thread 1172 ::abort(); 1173} 1174 1175// This method is a copy of JDK's sysGetLastErrorString 1176// from src/solaris/hpi/src/system_md.c 1177 1178size_t os::lasterror(char *buf, size_t len) { 1179 1180 if (errno == 0) return 0; 1181 1182 const char *s = ::strerror(errno); 1183 size_t n = ::strlen(s); 1184 if (n >= len) { 1185 n = len - 1; 1186 } 1187 ::strncpy(buf, s, n); 1188 buf[n] = '\0'; 1189 return n; 1190} 1191 1192// Information of current thread in variety of formats 1193pid_t os::Bsd::gettid() { 1194 int retval = -1; 1195 1196#ifdef __APPLE__ //XNU kernel 1197 // despite the fact mach port is actually not a thread id use it 1198 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 1199 retval = ::pthread_mach_thread_np(::pthread_self()); 1200 guarantee(retval != 0, "just checking"); 1201 return retval; 1202 1203#elif __FreeBSD__ 1204 retval = syscall(SYS_thr_self); 1205#elif __OpenBSD__ 1206 retval = syscall(SYS_getthrid); 1207#elif __NetBSD__ 1208 retval = (pid_t) syscall(SYS__lwp_self); 1209#endif 1210 1211 if (retval == -1) { 1212 return getpid(); 1213 } 1214} 1215 1216intx os::current_thread_id() { 1217#ifdef __APPLE__ 1218 return (intx)::pthread_mach_thread_np(::pthread_self()); 1219#else 1220 return (intx)::pthread_self(); 1221#endif 1222} 1223 1224int os::current_process_id() { 1225 1226 // Under the old bsd thread library, bsd gives each thread 1227 // its own process id. Because of this each thread will return 1228 // a different pid if this method were to return the result 1229 // of getpid(2). Bsd provides no api that returns the pid 1230 // of the launcher thread for the vm. This implementation 1231 // returns a unique pid, the pid of the launcher thread 1232 // that starts the vm 'process'. 1233 1234 // Under the NPTL, getpid() returns the same pid as the 1235 // launcher thread rather than a unique pid per thread. 1236 // Use gettid() if you want the old pre NPTL behaviour. 1237 1238 // if you are looking for the result of a call to getpid() that 1239 // returns a unique pid for the calling thread, then look at the 1240 // OSThread::thread_id() method in osThread_bsd.hpp file 1241 1242 return (int)(_initial_pid ? _initial_pid : getpid()); 1243} 1244 1245// DLL functions 1246 1247#define JNI_LIB_PREFIX "lib" 1248#ifdef __APPLE__ 1249#define JNI_LIB_SUFFIX ".dylib" 1250#else 1251#define JNI_LIB_SUFFIX ".so" 1252#endif 1253 1254const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1255 1256// This must be hard coded because it's the system's temporary 1257// directory not the java application's temp directory, ala java.io.tmpdir. 1258#ifdef __APPLE__ 1259// macosx has a secure per-user temporary directory 1260char temp_path_storage[PATH_MAX]; 1261const char* os::get_temp_directory() { 1262 static char *temp_path = NULL; 1263 if (temp_path == NULL) { 1264 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1265 if (pathSize == 0 || pathSize > PATH_MAX) { 1266 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1267 } 1268 temp_path = temp_path_storage; 1269 } 1270 return temp_path; 1271} 1272#else /* __APPLE__ */ 1273const char* os::get_temp_directory() { return "/tmp"; } 1274#endif /* __APPLE__ */ 1275 1276static bool file_exists(const char* filename) { 1277 struct stat statbuf; 1278 if (filename == NULL || strlen(filename) == 0) { 1279 return false; 1280 } 1281 return os::stat(filename, &statbuf) == 0; 1282} 1283 1284bool os::dll_build_name(char* buffer, size_t buflen, 1285 const char* pname, const char* fname) { 1286 bool retval = false; 1287 // Copied from libhpi 1288 const size_t pnamelen = pname ? strlen(pname) : 0; 1289 1290 // Return error on buffer overflow. 1291 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1292 return retval; 1293 } 1294 1295 if (pnamelen == 0) { 1296 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1297 retval = true; 1298 } else if (strchr(pname, *os::path_separator()) != NULL) { 1299 int n; 1300 char** pelements = split_path(pname, &n); 1301 if (pelements == NULL) { 1302 return false; 1303 } 1304 for (int i = 0; i < n; i++) { 1305 // Really shouldn't be NULL, but check can't hurt 1306 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1307 continue; // skip the empty path values 1308 } 1309 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1310 pelements[i], fname); 1311 if (file_exists(buffer)) { 1312 retval = true; 1313 break; 1314 } 1315 } 1316 // release the storage 1317 for (int i = 0; i < n; i++) { 1318 if (pelements[i] != NULL) { 1319 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); 1320 } 1321 } 1322 if (pelements != NULL) { 1323 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); 1324 } 1325 } else { 1326 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1327 retval = true; 1328 } 1329 return retval; 1330} 1331 1332// check if addr is inside libjvm.so 1333bool os::address_is_in_vm(address addr) { 1334 static address libjvm_base_addr; 1335 Dl_info dlinfo; 1336 1337 if (libjvm_base_addr == NULL) { 1338 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { 1339 libjvm_base_addr = (address)dlinfo.dli_fbase; 1340 } 1341 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1342 } 1343 1344 if (dladdr((void *)addr, &dlinfo) != 0) { 1345 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1346 } 1347 1348 return false; 1349} 1350 1351 1352#define MACH_MAXSYMLEN 256 1353 1354bool os::dll_address_to_function_name(address addr, char *buf, 1355 int buflen, int *offset) { 1356 // buf is not optional, but offset is optional 1357 assert(buf != NULL, "sanity check"); 1358 1359 Dl_info dlinfo; 1360 char localbuf[MACH_MAXSYMLEN]; 1361 1362 if (dladdr((void*)addr, &dlinfo) != 0) { 1363 // see if we have a matching symbol 1364 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { 1365 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1366 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1367 } 1368 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1369 return true; 1370 } 1371 // no matching symbol so try for just file info 1372 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { 1373 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1374 buf, buflen, offset, dlinfo.dli_fname)) { 1375 return true; 1376 } 1377 } 1378 1379 // Handle non-dynamic manually: 1380 if (dlinfo.dli_fbase != NULL && 1381 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, 1382 dlinfo.dli_fbase)) { 1383 if (!Decoder::demangle(localbuf, buf, buflen)) { 1384 jio_snprintf(buf, buflen, "%s", localbuf); 1385 } 1386 return true; 1387 } 1388 } 1389 buf[0] = '\0'; 1390 if (offset != NULL) *offset = -1; 1391 return false; 1392} 1393 1394// ported from solaris version 1395bool os::dll_address_to_library_name(address addr, char* buf, 1396 int buflen, int* offset) { 1397 // buf is not optional, but offset is optional 1398 assert(buf != NULL, "sanity check"); 1399 1400 Dl_info dlinfo; 1401 1402 if (dladdr((void*)addr, &dlinfo) != 0) { 1403 if (dlinfo.dli_fname != NULL) { 1404 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1405 } 1406 if (dlinfo.dli_fbase != NULL && offset != NULL) { 1407 *offset = addr - (address)dlinfo.dli_fbase; 1408 } 1409 return true; 1410 } 1411 1412 buf[0] = '\0'; 1413 if (offset) *offset = -1; 1414 return false; 1415} 1416 1417// Loads .dll/.so and 1418// in case of error it checks if .dll/.so was built for the 1419// same architecture as Hotspot is running on 1420 1421#ifdef __APPLE__ 1422void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 1423 void * result= ::dlopen(filename, RTLD_LAZY); 1424 if (result != NULL) { 1425 // Successful loading 1426 return result; 1427 } 1428 1429 // Read system error message into ebuf 1430 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1431 ebuf[ebuflen-1]='\0'; 1432 1433 return NULL; 1434} 1435#else 1436void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 1437{ 1438 void * result= ::dlopen(filename, RTLD_LAZY); 1439 if (result != NULL) { 1440 // Successful loading 1441 return result; 1442 } 1443 1444 Elf32_Ehdr elf_head; 1445 1446 // Read system error message into ebuf 1447 // It may or may not be overwritten below 1448 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 1449 ebuf[ebuflen-1]='\0'; 1450 int diag_msg_max_length=ebuflen-strlen(ebuf); 1451 char* diag_msg_buf=ebuf+strlen(ebuf); 1452 1453 if (diag_msg_max_length==0) { 1454 // No more space in ebuf for additional diagnostics message 1455 return NULL; 1456 } 1457 1458 1459 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 1460 1461 if (file_descriptor < 0) { 1462 // Can't open library, report dlerror() message 1463 return NULL; 1464 } 1465 1466 bool failed_to_read_elf_head= 1467 (sizeof(elf_head)!= 1468 (::read(file_descriptor, &elf_head,sizeof(elf_head)))); 1469 1470 ::close(file_descriptor); 1471 if (failed_to_read_elf_head) { 1472 // file i/o error - report dlerror() msg 1473 return NULL; 1474 } 1475 1476 typedef struct { 1477 Elf32_Half code; // Actual value as defined in elf.h 1478 Elf32_Half compat_class; // Compatibility of archs at VM's sense 1479 char elf_class; // 32 or 64 bit 1480 char endianess; // MSB or LSB 1481 char* name; // String representation 1482 } arch_t; 1483 1484 #ifndef EM_486 1485 #define EM_486 6 /* Intel 80486 */ 1486 #endif 1487 1488 #ifndef EM_MIPS_RS3_LE 1489 #define EM_MIPS_RS3_LE 10 /* MIPS */ 1490 #endif 1491 1492 #ifndef EM_PPC64 1493 #define EM_PPC64 21 /* PowerPC64 */ 1494 #endif 1495 1496 #ifndef EM_S390 1497 #define EM_S390 22 /* IBM System/390 */ 1498 #endif 1499 1500 #ifndef EM_IA_64 1501 #define EM_IA_64 50 /* HP/Intel IA-64 */ 1502 #endif 1503 1504 #ifndef EM_X86_64 1505 #define EM_X86_64 62 /* AMD x86-64 */ 1506 #endif 1507 1508 static const arch_t arch_array[]={ 1509 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1510 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 1511 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 1512 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 1513 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1514 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 1515 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 1516 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 1517 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 1518 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 1519 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 1520 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 1521 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 1522 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 1523 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 1524 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 1525 }; 1526 1527 #if (defined IA32) 1528 static Elf32_Half running_arch_code=EM_386; 1529 #elif (defined AMD64) 1530 static Elf32_Half running_arch_code=EM_X86_64; 1531 #elif (defined IA64) 1532 static Elf32_Half running_arch_code=EM_IA_64; 1533 #elif (defined __sparc) && (defined _LP64) 1534 static Elf32_Half running_arch_code=EM_SPARCV9; 1535 #elif (defined __sparc) && (!defined _LP64) 1536 static Elf32_Half running_arch_code=EM_SPARC; 1537 #elif (defined __powerpc64__) 1538 static Elf32_Half running_arch_code=EM_PPC64; 1539 #elif (defined __powerpc__) 1540 static Elf32_Half running_arch_code=EM_PPC; 1541 #elif (defined ARM) 1542 static Elf32_Half running_arch_code=EM_ARM; 1543 #elif (defined S390) 1544 static Elf32_Half running_arch_code=EM_S390; 1545 #elif (defined ALPHA) 1546 static Elf32_Half running_arch_code=EM_ALPHA; 1547 #elif (defined MIPSEL) 1548 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 1549 #elif (defined PARISC) 1550 static Elf32_Half running_arch_code=EM_PARISC; 1551 #elif (defined MIPS) 1552 static Elf32_Half running_arch_code=EM_MIPS; 1553 #elif (defined M68K) 1554 static Elf32_Half running_arch_code=EM_68K; 1555 #else 1556 #error Method os::dll_load requires that one of following is defined:\ 1557 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 1558 #endif 1559 1560 // Identify compatability class for VM's architecture and library's architecture 1561 // Obtain string descriptions for architectures 1562 1563 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 1564 int running_arch_index=-1; 1565 1566 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { 1567 if (running_arch_code == arch_array[i].code) { 1568 running_arch_index = i; 1569 } 1570 if (lib_arch.code == arch_array[i].code) { 1571 lib_arch.compat_class = arch_array[i].compat_class; 1572 lib_arch.name = arch_array[i].name; 1573 } 1574 } 1575 1576 assert(running_arch_index != -1, 1577 "Didn't find running architecture code (running_arch_code) in arch_array"); 1578 if (running_arch_index == -1) { 1579 // Even though running architecture detection failed 1580 // we may still continue with reporting dlerror() message 1581 return NULL; 1582 } 1583 1584 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 1585 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 1586 return NULL; 1587 } 1588 1589#ifndef S390 1590 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 1591 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 1592 return NULL; 1593 } 1594#endif // !S390 1595 1596 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 1597 if (lib_arch.name!=NULL) { 1598 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1599 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 1600 lib_arch.name, arch_array[running_arch_index].name); 1601 } else { 1602 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 1603 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 1604 lib_arch.code, 1605 arch_array[running_arch_index].name); 1606 } 1607 } 1608 1609 return NULL; 1610} 1611#endif /* !__APPLE__ */ 1612 1613void* os::get_default_process_handle() { 1614#ifdef __APPLE__ 1615 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY 1616 // to avoid finding unexpected symbols on second (or later) 1617 // loads of a library. 1618 return (void*)::dlopen(NULL, RTLD_FIRST); 1619#else 1620 return (void*)::dlopen(NULL, RTLD_LAZY); 1621#endif 1622} 1623 1624// XXX: Do we need a lock around this as per Linux? 1625void* os::dll_lookup(void* handle, const char* name) { 1626 return dlsym(handle, name); 1627} 1628 1629 1630static bool _print_ascii_file(const char* filename, outputStream* st) { 1631 int fd = ::open(filename, O_RDONLY); 1632 if (fd == -1) { 1633 return false; 1634 } 1635 1636 char buf[32]; 1637 int bytes; 1638 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 1639 st->print_raw(buf, bytes); 1640 } 1641 1642 ::close(fd); 1643 1644 return true; 1645} 1646 1647void os::print_dll_info(outputStream *st) { 1648 st->print_cr("Dynamic libraries:"); 1649#ifdef RTLD_DI_LINKMAP 1650 Dl_info dli; 1651 void *handle; 1652 Link_map *map; 1653 Link_map *p; 1654 1655 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1656 dli.dli_fname == NULL) { 1657 st->print_cr("Error: Cannot print dynamic libraries."); 1658 return; 1659 } 1660 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1661 if (handle == NULL) { 1662 st->print_cr("Error: Cannot print dynamic libraries."); 1663 return; 1664 } 1665 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1666 if (map == NULL) { 1667 st->print_cr("Error: Cannot print dynamic libraries."); 1668 return; 1669 } 1670 1671 while (map->l_prev != NULL) 1672 map = map->l_prev; 1673 1674 while (map != NULL) { 1675 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 1676 map = map->l_next; 1677 } 1678 1679 dlclose(handle); 1680#elif defined(__APPLE__) 1681 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1682 st->print_cr(PTR_FORMAT " \t%s", _dyld_get_image_header(i), 1683 _dyld_get_image_name(i)); 1684 } 1685#else 1686 st->print_cr("Error: Cannot print dynamic libraries."); 1687#endif 1688} 1689 1690void os::print_os_info_brief(outputStream* st) { 1691 st->print("Bsd"); 1692 1693 os::Posix::print_uname_info(st); 1694} 1695 1696void os::print_os_info(outputStream* st) { 1697 st->print("OS:"); 1698 st->print("Bsd"); 1699 1700 os::Posix::print_uname_info(st); 1701 1702 os::Posix::print_rlimit_info(st); 1703 1704 os::Posix::print_load_average(st); 1705} 1706 1707void os::pd_print_cpu_info(outputStream* st) { 1708 // Nothing to do for now. 1709} 1710 1711void os::print_memory_info(outputStream* st) { 1712 1713 st->print("Memory:"); 1714 st->print(" %dk page", os::vm_page_size()>>10); 1715 1716 st->print(", physical " UINT64_FORMAT "k", 1717 os::physical_memory() >> 10); 1718 st->print("(" UINT64_FORMAT "k free)", 1719 os::available_memory() >> 10); 1720 st->cr(); 1721 1722 // meminfo 1723 st->print("\n/proc/meminfo:\n"); 1724 _print_ascii_file("/proc/meminfo", st); 1725 st->cr(); 1726} 1727 1728void os::print_siginfo(outputStream* st, void* siginfo) { 1729 const siginfo_t* si = (const siginfo_t*)siginfo; 1730 1731 os::Posix::print_siginfo_brief(st, si); 1732 1733 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1734 UseSharedSpaces) { 1735 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1736 if (mapinfo->is_in_shared_space(si->si_addr)) { 1737 st->print("\n\nError accessing class data sharing archive." \ 1738 " Mapped file inaccessible during execution, " \ 1739 " possible disk/network problem."); 1740 } 1741 } 1742 st->cr(); 1743} 1744 1745 1746static void print_signal_handler(outputStream* st, int sig, 1747 char* buf, size_t buflen); 1748 1749void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1750 st->print_cr("Signal Handlers:"); 1751 print_signal_handler(st, SIGSEGV, buf, buflen); 1752 print_signal_handler(st, SIGBUS , buf, buflen); 1753 print_signal_handler(st, SIGFPE , buf, buflen); 1754 print_signal_handler(st, SIGPIPE, buf, buflen); 1755 print_signal_handler(st, SIGXFSZ, buf, buflen); 1756 print_signal_handler(st, SIGILL , buf, buflen); 1757 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1758 print_signal_handler(st, SR_signum, buf, buflen); 1759 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1760 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1761 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1762 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1763} 1764 1765static char saved_jvm_path[MAXPATHLEN] = {0}; 1766 1767// Find the full path to the current module, libjvm 1768void os::jvm_path(char *buf, jint buflen) { 1769 // Error checking. 1770 if (buflen < MAXPATHLEN) { 1771 assert(false, "must use a large-enough buffer"); 1772 buf[0] = '\0'; 1773 return; 1774 } 1775 // Lazy resolve the path to current module. 1776 if (saved_jvm_path[0] != 0) { 1777 strcpy(buf, saved_jvm_path); 1778 return; 1779 } 1780 1781 char dli_fname[MAXPATHLEN]; 1782 bool ret = dll_address_to_library_name( 1783 CAST_FROM_FN_PTR(address, os::jvm_path), 1784 dli_fname, sizeof(dli_fname), NULL); 1785 assert(ret, "cannot locate libjvm"); 1786 char *rp = NULL; 1787 if (ret && dli_fname[0] != '\0') { 1788 rp = realpath(dli_fname, buf); 1789 } 1790 if (rp == NULL) 1791 return; 1792 1793 if (Arguments::sun_java_launcher_is_altjvm()) { 1794 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1795 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1796 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1797 // appears at the right place in the string, then assume we are 1798 // installed in a JDK and we're done. Otherwise, check for a 1799 // JAVA_HOME environment variable and construct a path to the JVM 1800 // being overridden. 1801 1802 const char *p = buf + strlen(buf) - 1; 1803 for (int count = 0; p > buf && count < 5; ++count) { 1804 for (--p; p > buf && *p != '/'; --p) 1805 /* empty */ ; 1806 } 1807 1808 if (strncmp(p, "/jre/lib/", 9) != 0) { 1809 // Look for JAVA_HOME in the environment. 1810 char* java_home_var = ::getenv("JAVA_HOME"); 1811 if (java_home_var != NULL && java_home_var[0] != 0) { 1812 char* jrelib_p; 1813 int len; 1814 1815 // Check the current module name "libjvm" 1816 p = strrchr(buf, '/'); 1817 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1818 1819 rp = realpath(java_home_var, buf); 1820 if (rp == NULL) 1821 return; 1822 1823 // determine if this is a legacy image or modules image 1824 // modules image doesn't have "jre" subdirectory 1825 len = strlen(buf); 1826 assert(len < buflen, "Ran out of buffer space"); 1827 jrelib_p = buf + len; 1828 1829 // Add the appropriate library subdir 1830 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1831 if (0 != access(buf, F_OK)) { 1832 snprintf(jrelib_p, buflen-len, "/lib"); 1833 } 1834 1835 // Add the appropriate client or server subdir 1836 len = strlen(buf); 1837 jrelib_p = buf + len; 1838 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1839 if (0 != access(buf, F_OK)) { 1840 snprintf(jrelib_p, buflen-len, "%s", ""); 1841 } 1842 1843 // If the path exists within JAVA_HOME, add the JVM library name 1844 // to complete the path to JVM being overridden. Otherwise fallback 1845 // to the path to the current library. 1846 if (0 == access(buf, F_OK)) { 1847 // Use current module name "libjvm" 1848 len = strlen(buf); 1849 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1850 } else { 1851 // Fall back to path of current library 1852 rp = realpath(dli_fname, buf); 1853 if (rp == NULL) 1854 return; 1855 } 1856 } 1857 } 1858 } 1859 1860 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1861} 1862 1863void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1864 // no prefix required, not even "_" 1865} 1866 1867void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1868 // no suffix required 1869} 1870 1871//////////////////////////////////////////////////////////////////////////////// 1872// sun.misc.Signal support 1873 1874static volatile jint sigint_count = 0; 1875 1876static void 1877UserHandler(int sig, void *siginfo, void *context) { 1878 // 4511530 - sem_post is serialized and handled by the manager thread. When 1879 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1880 // don't want to flood the manager thread with sem_post requests. 1881 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1882 return; 1883 1884 // Ctrl-C is pressed during error reporting, likely because the error 1885 // handler fails to abort. Let VM die immediately. 1886 if (sig == SIGINT && is_error_reported()) { 1887 os::die(); 1888 } 1889 1890 os::signal_notify(sig); 1891} 1892 1893void* os::user_handler() { 1894 return CAST_FROM_FN_PTR(void*, UserHandler); 1895} 1896 1897extern "C" { 1898 typedef void (*sa_handler_t)(int); 1899 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1900} 1901 1902void* os::signal(int signal_number, void* handler) { 1903 struct sigaction sigAct, oldSigAct; 1904 1905 sigfillset(&(sigAct.sa_mask)); 1906 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1907 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1908 1909 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1910 // -1 means registration failed 1911 return (void *)-1; 1912 } 1913 1914 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1915} 1916 1917void os::signal_raise(int signal_number) { 1918 ::raise(signal_number); 1919} 1920 1921/* 1922 * The following code is moved from os.cpp for making this 1923 * code platform specific, which it is by its very nature. 1924 */ 1925 1926// Will be modified when max signal is changed to be dynamic 1927int os::sigexitnum_pd() { 1928 return NSIG; 1929} 1930 1931// a counter for each possible signal value 1932static volatile jint pending_signals[NSIG+1] = { 0 }; 1933 1934// Bsd(POSIX) specific hand shaking semaphore. 1935#ifdef __APPLE__ 1936typedef semaphore_t os_semaphore_t; 1937#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1938#define SEM_WAIT(sem) semaphore_wait(sem) 1939#define SEM_POST(sem) semaphore_signal(sem) 1940#define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1941#else 1942typedef sem_t os_semaphore_t; 1943#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1944#define SEM_WAIT(sem) sem_wait(&sem) 1945#define SEM_POST(sem) sem_post(&sem) 1946#define SEM_DESTROY(sem) sem_destroy(&sem) 1947#endif 1948 1949class Semaphore : public StackObj { 1950 public: 1951 Semaphore(); 1952 ~Semaphore(); 1953 void signal(); 1954 void wait(); 1955 bool trywait(); 1956 bool timedwait(unsigned int sec, int nsec); 1957 private: 1958 jlong currenttime() const; 1959 os_semaphore_t _semaphore; 1960}; 1961 1962Semaphore::Semaphore() : _semaphore(0) { 1963 SEM_INIT(_semaphore, 0); 1964} 1965 1966Semaphore::~Semaphore() { 1967 SEM_DESTROY(_semaphore); 1968} 1969 1970void Semaphore::signal() { 1971 SEM_POST(_semaphore); 1972} 1973 1974void Semaphore::wait() { 1975 SEM_WAIT(_semaphore); 1976} 1977 1978jlong Semaphore::currenttime() const { 1979 struct timeval tv; 1980 gettimeofday(&tv, NULL); 1981 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1982} 1983 1984#ifdef __APPLE__ 1985bool Semaphore::trywait() { 1986 return timedwait(0, 0); 1987} 1988 1989bool Semaphore::timedwait(unsigned int sec, int nsec) { 1990 kern_return_t kr = KERN_ABORTED; 1991 mach_timespec_t waitspec; 1992 waitspec.tv_sec = sec; 1993 waitspec.tv_nsec = nsec; 1994 1995 jlong starttime = currenttime(); 1996 1997 kr = semaphore_timedwait(_semaphore, waitspec); 1998 while (kr == KERN_ABORTED) { 1999 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 2000 2001 jlong current = currenttime(); 2002 jlong passedtime = current - starttime; 2003 2004 if (passedtime >= totalwait) { 2005 waitspec.tv_sec = 0; 2006 waitspec.tv_nsec = 0; 2007 } else { 2008 jlong waittime = totalwait - (current - starttime); 2009 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2010 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2011 } 2012 2013 kr = semaphore_timedwait(_semaphore, waitspec); 2014 } 2015 2016 return kr == KERN_SUCCESS; 2017} 2018 2019#else 2020 2021bool Semaphore::trywait() { 2022 return sem_trywait(&_semaphore) == 0; 2023} 2024 2025bool Semaphore::timedwait(unsigned int sec, int nsec) { 2026 struct timespec ts; 2027 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2028 2029 while (1) { 2030 int result = sem_timedwait(&_semaphore, &ts); 2031 if (result == 0) { 2032 return true; 2033 } else if (errno == EINTR) { 2034 continue; 2035 } else if (errno == ETIMEDOUT) { 2036 return false; 2037 } else { 2038 return false; 2039 } 2040 } 2041} 2042 2043#endif // __APPLE__ 2044 2045static os_semaphore_t sig_sem; 2046static Semaphore sr_semaphore; 2047 2048void os::signal_init_pd() { 2049 // Initialize signal structures 2050 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2051 2052 // Initialize signal semaphore 2053 ::SEM_INIT(sig_sem, 0); 2054} 2055 2056void os::signal_notify(int sig) { 2057 Atomic::inc(&pending_signals[sig]); 2058 ::SEM_POST(sig_sem); 2059} 2060 2061static int check_pending_signals(bool wait) { 2062 Atomic::store(0, &sigint_count); 2063 for (;;) { 2064 for (int i = 0; i < NSIG + 1; i++) { 2065 jint n = pending_signals[i]; 2066 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2067 return i; 2068 } 2069 } 2070 if (!wait) { 2071 return -1; 2072 } 2073 JavaThread *thread = JavaThread::current(); 2074 ThreadBlockInVM tbivm(thread); 2075 2076 bool threadIsSuspended; 2077 do { 2078 thread->set_suspend_equivalent(); 2079 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2080 ::SEM_WAIT(sig_sem); 2081 2082 // were we externally suspended while we were waiting? 2083 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2084 if (threadIsSuspended) { 2085 // 2086 // The semaphore has been incremented, but while we were waiting 2087 // another thread suspended us. We don't want to continue running 2088 // while suspended because that would surprise the thread that 2089 // suspended us. 2090 // 2091 ::SEM_POST(sig_sem); 2092 2093 thread->java_suspend_self(); 2094 } 2095 } while (threadIsSuspended); 2096 } 2097} 2098 2099int os::signal_lookup() { 2100 return check_pending_signals(false); 2101} 2102 2103int os::signal_wait() { 2104 return check_pending_signals(true); 2105} 2106 2107//////////////////////////////////////////////////////////////////////////////// 2108// Virtual Memory 2109 2110int os::vm_page_size() { 2111 // Seems redundant as all get out 2112 assert(os::Bsd::page_size() != -1, "must call os::init"); 2113 return os::Bsd::page_size(); 2114} 2115 2116// Solaris allocates memory by pages. 2117int os::vm_allocation_granularity() { 2118 assert(os::Bsd::page_size() != -1, "must call os::init"); 2119 return os::Bsd::page_size(); 2120} 2121 2122// Rationale behind this function: 2123// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2124// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2125// samples for JITted code. Here we create private executable mapping over the code cache 2126// and then we can use standard (well, almost, as mapping can change) way to provide 2127// info for the reporting script by storing timestamp and location of symbol 2128void bsd_wrap_code(char* base, size_t size) { 2129 static volatile jint cnt = 0; 2130 2131 if (!UseOprofile) { 2132 return; 2133 } 2134 2135 char buf[PATH_MAX + 1]; 2136 int num = Atomic::add(1, &cnt); 2137 2138 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2139 os::get_temp_directory(), os::current_process_id(), num); 2140 unlink(buf); 2141 2142 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2143 2144 if (fd != -1) { 2145 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2146 if (rv != (off_t)-1) { 2147 if (::write(fd, "", 1) == 1) { 2148 mmap(base, size, 2149 PROT_READ|PROT_WRITE|PROT_EXEC, 2150 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2151 } 2152 } 2153 ::close(fd); 2154 unlink(buf); 2155 } 2156} 2157 2158static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2159 int err) { 2160 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2161 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2162 strerror(err), err); 2163} 2164 2165// NOTE: Bsd kernel does not really reserve the pages for us. 2166// All it does is to check if there are enough free pages 2167// left at the time of mmap(). This could be a potential 2168// problem. 2169bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2170 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2171#ifdef __OpenBSD__ 2172 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2173 if (::mprotect(addr, size, prot) == 0) { 2174 return true; 2175 } 2176#else 2177 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2178 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2179 if (res != (uintptr_t) MAP_FAILED) { 2180 return true; 2181 } 2182#endif 2183 2184 // Warn about any commit errors we see in non-product builds just 2185 // in case mmap() doesn't work as described on the man page. 2186 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2187 2188 return false; 2189} 2190 2191bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2192 bool exec) { 2193 // alignment_hint is ignored on this OS 2194 return pd_commit_memory(addr, size, exec); 2195} 2196 2197void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2198 const char* mesg) { 2199 assert(mesg != NULL, "mesg must be specified"); 2200 if (!pd_commit_memory(addr, size, exec)) { 2201 // add extra info in product mode for vm_exit_out_of_memory(): 2202 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2203 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2204 } 2205} 2206 2207void os::pd_commit_memory_or_exit(char* addr, size_t size, 2208 size_t alignment_hint, bool exec, 2209 const char* mesg) { 2210 // alignment_hint is ignored on this OS 2211 pd_commit_memory_or_exit(addr, size, exec, mesg); 2212} 2213 2214void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2215} 2216 2217void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2218 ::madvise(addr, bytes, MADV_DONTNEED); 2219} 2220 2221void os::numa_make_global(char *addr, size_t bytes) { 2222} 2223 2224void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2225} 2226 2227bool os::numa_topology_changed() { return false; } 2228 2229size_t os::numa_get_groups_num() { 2230 return 1; 2231} 2232 2233int os::numa_get_group_id() { 2234 return 0; 2235} 2236 2237size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2238 if (size > 0) { 2239 ids[0] = 0; 2240 return 1; 2241 } 2242 return 0; 2243} 2244 2245bool os::get_page_info(char *start, page_info* info) { 2246 return false; 2247} 2248 2249char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2250 return end; 2251} 2252 2253 2254bool os::pd_uncommit_memory(char* addr, size_t size) { 2255#ifdef __OpenBSD__ 2256 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2257 return ::mprotect(addr, size, PROT_NONE) == 0; 2258#else 2259 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2260 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2261 return res != (uintptr_t) MAP_FAILED; 2262#endif 2263} 2264 2265bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2266 return os::commit_memory(addr, size, !ExecMem); 2267} 2268 2269// If this is a growable mapping, remove the guard pages entirely by 2270// munmap()ping them. If not, just call uncommit_memory(). 2271bool os::remove_stack_guard_pages(char* addr, size_t size) { 2272 return os::uncommit_memory(addr, size); 2273} 2274 2275static address _highest_vm_reserved_address = NULL; 2276 2277// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2278// at 'requested_addr'. If there are existing memory mappings at the same 2279// location, however, they will be overwritten. If 'fixed' is false, 2280// 'requested_addr' is only treated as a hint, the return value may or 2281// may not start from the requested address. Unlike Bsd mmap(), this 2282// function returns NULL to indicate failure. 2283static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2284 char * addr; 2285 int flags; 2286 2287 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2288 if (fixed) { 2289 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2290 flags |= MAP_FIXED; 2291 } 2292 2293 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2294 // touch an uncommitted page. Otherwise, the read/write might 2295 // succeed if we have enough swap space to back the physical page. 2296 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2297 flags, -1, 0); 2298 2299 if (addr != MAP_FAILED) { 2300 // anon_mmap() should only get called during VM initialization, 2301 // don't need lock (actually we can skip locking even it can be called 2302 // from multiple threads, because _highest_vm_reserved_address is just a 2303 // hint about the upper limit of non-stack memory regions.) 2304 if ((address)addr + bytes > _highest_vm_reserved_address) { 2305 _highest_vm_reserved_address = (address)addr + bytes; 2306 } 2307 } 2308 2309 return addr == MAP_FAILED ? NULL : addr; 2310} 2311 2312// Don't update _highest_vm_reserved_address, because there might be memory 2313// regions above addr + size. If so, releasing a memory region only creates 2314// a hole in the address space, it doesn't help prevent heap-stack collision. 2315// 2316static int anon_munmap(char * addr, size_t size) { 2317 return ::munmap(addr, size) == 0; 2318} 2319 2320char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2321 size_t alignment_hint) { 2322 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2323} 2324 2325bool os::pd_release_memory(char* addr, size_t size) { 2326 return anon_munmap(addr, size); 2327} 2328 2329static bool bsd_mprotect(char* addr, size_t size, int prot) { 2330 // Bsd wants the mprotect address argument to be page aligned. 2331 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2332 2333 // According to SUSv3, mprotect() should only be used with mappings 2334 // established by mmap(), and mmap() always maps whole pages. Unaligned 2335 // 'addr' likely indicates problem in the VM (e.g. trying to change 2336 // protection of malloc'ed or statically allocated memory). Check the 2337 // caller if you hit this assert. 2338 assert(addr == bottom, "sanity check"); 2339 2340 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2341 return ::mprotect(bottom, size, prot) == 0; 2342} 2343 2344// Set protections specified 2345bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2346 bool is_committed) { 2347 unsigned int p = 0; 2348 switch (prot) { 2349 case MEM_PROT_NONE: p = PROT_NONE; break; 2350 case MEM_PROT_READ: p = PROT_READ; break; 2351 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2352 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2353 default: 2354 ShouldNotReachHere(); 2355 } 2356 // is_committed is unused. 2357 return bsd_mprotect(addr, bytes, p); 2358} 2359 2360bool os::guard_memory(char* addr, size_t size) { 2361 return bsd_mprotect(addr, size, PROT_NONE); 2362} 2363 2364bool os::unguard_memory(char* addr, size_t size) { 2365 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2366} 2367 2368bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2369 return false; 2370} 2371 2372// Large page support 2373 2374static size_t _large_page_size = 0; 2375 2376void os::large_page_init() { 2377} 2378 2379 2380char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2381 fatal("This code is not used or maintained."); 2382 2383 // "exec" is passed in but not used. Creating the shared image for 2384 // the code cache doesn't have an SHM_X executable permission to check. 2385 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2386 2387 key_t key = IPC_PRIVATE; 2388 char *addr; 2389 2390 bool warn_on_failure = UseLargePages && 2391 (!FLAG_IS_DEFAULT(UseLargePages) || 2392 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2393 ); 2394 2395 // Create a large shared memory region to attach to based on size. 2396 // Currently, size is the total size of the heap 2397 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2398 if (shmid == -1) { 2399 // Possible reasons for shmget failure: 2400 // 1. shmmax is too small for Java heap. 2401 // > check shmmax value: cat /proc/sys/kernel/shmmax 2402 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2403 // 2. not enough large page memory. 2404 // > check available large pages: cat /proc/meminfo 2405 // > increase amount of large pages: 2406 // echo new_value > /proc/sys/vm/nr_hugepages 2407 // Note 1: different Bsd may use different name for this property, 2408 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2409 // Note 2: it's possible there's enough physical memory available but 2410 // they are so fragmented after a long run that they can't 2411 // coalesce into large pages. Try to reserve large pages when 2412 // the system is still "fresh". 2413 if (warn_on_failure) { 2414 warning("Failed to reserve shared memory (errno = %d).", errno); 2415 } 2416 return NULL; 2417 } 2418 2419 // attach to the region 2420 addr = (char*)shmat(shmid, req_addr, 0); 2421 int err = errno; 2422 2423 // Remove shmid. If shmat() is successful, the actual shared memory segment 2424 // will be deleted when it's detached by shmdt() or when the process 2425 // terminates. If shmat() is not successful this will remove the shared 2426 // segment immediately. 2427 shmctl(shmid, IPC_RMID, NULL); 2428 2429 if ((intptr_t)addr == -1) { 2430 if (warn_on_failure) { 2431 warning("Failed to attach shared memory (errno = %d).", err); 2432 } 2433 return NULL; 2434 } 2435 2436 // The memory is committed 2437 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2438 2439 return addr; 2440} 2441 2442bool os::release_memory_special(char* base, size_t bytes) { 2443 if (MemTracker::tracking_level() > NMT_minimal) { 2444 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2445 // detaching the SHM segment will also delete it, see reserve_memory_special() 2446 int rslt = shmdt(base); 2447 if (rslt == 0) { 2448 tkr.record((address)base, bytes); 2449 return true; 2450 } else { 2451 return false; 2452 } 2453 } else { 2454 return shmdt(base) == 0; 2455 } 2456} 2457 2458size_t os::large_page_size() { 2459 return _large_page_size; 2460} 2461 2462// HugeTLBFS allows application to commit large page memory on demand; 2463// with SysV SHM the entire memory region must be allocated as shared 2464// memory. 2465bool os::can_commit_large_page_memory() { 2466 return UseHugeTLBFS; 2467} 2468 2469bool os::can_execute_large_page_memory() { 2470 return UseHugeTLBFS; 2471} 2472 2473// Reserve memory at an arbitrary address, only if that area is 2474// available (and not reserved for something else). 2475 2476char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2477 const int max_tries = 10; 2478 char* base[max_tries]; 2479 size_t size[max_tries]; 2480 const size_t gap = 0x000000; 2481 2482 // Assert only that the size is a multiple of the page size, since 2483 // that's all that mmap requires, and since that's all we really know 2484 // about at this low abstraction level. If we need higher alignment, 2485 // we can either pass an alignment to this method or verify alignment 2486 // in one of the methods further up the call chain. See bug 5044738. 2487 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2488 2489 // Repeatedly allocate blocks until the block is allocated at the 2490 // right spot. Give up after max_tries. Note that reserve_memory() will 2491 // automatically update _highest_vm_reserved_address if the call is 2492 // successful. The variable tracks the highest memory address every reserved 2493 // by JVM. It is used to detect heap-stack collision if running with 2494 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2495 // space than needed, it could confuse the collision detecting code. To 2496 // solve the problem, save current _highest_vm_reserved_address and 2497 // calculate the correct value before return. 2498 address old_highest = _highest_vm_reserved_address; 2499 2500 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2501 // if kernel honors the hint then we can return immediately. 2502 char * addr = anon_mmap(requested_addr, bytes, false); 2503 if (addr == requested_addr) { 2504 return requested_addr; 2505 } 2506 2507 if (addr != NULL) { 2508 // mmap() is successful but it fails to reserve at the requested address 2509 anon_munmap(addr, bytes); 2510 } 2511 2512 int i; 2513 for (i = 0; i < max_tries; ++i) { 2514 base[i] = reserve_memory(bytes); 2515 2516 if (base[i] != NULL) { 2517 // Is this the block we wanted? 2518 if (base[i] == requested_addr) { 2519 size[i] = bytes; 2520 break; 2521 } 2522 2523 // Does this overlap the block we wanted? Give back the overlapped 2524 // parts and try again. 2525 2526 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2527 if (top_overlap >= 0 && top_overlap < bytes) { 2528 unmap_memory(base[i], top_overlap); 2529 base[i] += top_overlap; 2530 size[i] = bytes - top_overlap; 2531 } else { 2532 size_t bottom_overlap = base[i] + bytes - requested_addr; 2533 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2534 unmap_memory(requested_addr, bottom_overlap); 2535 size[i] = bytes - bottom_overlap; 2536 } else { 2537 size[i] = bytes; 2538 } 2539 } 2540 } 2541 } 2542 2543 // Give back the unused reserved pieces. 2544 2545 for (int j = 0; j < i; ++j) { 2546 if (base[j] != NULL) { 2547 unmap_memory(base[j], size[j]); 2548 } 2549 } 2550 2551 if (i < max_tries) { 2552 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2553 return requested_addr; 2554 } else { 2555 _highest_vm_reserved_address = old_highest; 2556 return NULL; 2557 } 2558} 2559 2560size_t os::read(int fd, void *buf, unsigned int nBytes) { 2561 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2562} 2563 2564void os::naked_short_sleep(jlong ms) { 2565 struct timespec req; 2566 2567 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2568 req.tv_sec = 0; 2569 if (ms > 0) { 2570 req.tv_nsec = (ms % 1000) * 1000000; 2571 } 2572 else { 2573 req.tv_nsec = 1; 2574 } 2575 2576 nanosleep(&req, NULL); 2577 2578 return; 2579} 2580 2581// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2582void os::infinite_sleep() { 2583 while (true) { // sleep forever ... 2584 ::sleep(100); // ... 100 seconds at a time 2585 } 2586} 2587 2588// Used to convert frequent JVM_Yield() to nops 2589bool os::dont_yield() { 2590 return DontYieldALot; 2591} 2592 2593void os::naked_yield() { 2594 sched_yield(); 2595} 2596 2597//////////////////////////////////////////////////////////////////////////////// 2598// thread priority support 2599 2600// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2601// only supports dynamic priority, static priority must be zero. For real-time 2602// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2603// However, for large multi-threaded applications, SCHED_RR is not only slower 2604// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2605// of 5 runs - Sep 2005). 2606// 2607// The following code actually changes the niceness of kernel-thread/LWP. It 2608// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2609// not the entire user process, and user level threads are 1:1 mapped to kernel 2610// threads. It has always been the case, but could change in the future. For 2611// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2612// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2613 2614#if !defined(__APPLE__) 2615int os::java_to_os_priority[CriticalPriority + 1] = { 2616 19, // 0 Entry should never be used 2617 2618 0, // 1 MinPriority 2619 3, // 2 2620 6, // 3 2621 2622 10, // 4 2623 15, // 5 NormPriority 2624 18, // 6 2625 2626 21, // 7 2627 25, // 8 2628 28, // 9 NearMaxPriority 2629 2630 31, // 10 MaxPriority 2631 2632 31 // 11 CriticalPriority 2633}; 2634#else 2635/* Using Mach high-level priority assignments */ 2636int os::java_to_os_priority[CriticalPriority + 1] = { 2637 0, // 0 Entry should never be used (MINPRI_USER) 2638 2639 27, // 1 MinPriority 2640 28, // 2 2641 29, // 3 2642 2643 30, // 4 2644 31, // 5 NormPriority (BASEPRI_DEFAULT) 2645 32, // 6 2646 2647 33, // 7 2648 34, // 8 2649 35, // 9 NearMaxPriority 2650 2651 36, // 10 MaxPriority 2652 2653 36 // 11 CriticalPriority 2654}; 2655#endif 2656 2657static int prio_init() { 2658 if (ThreadPriorityPolicy == 1) { 2659 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2660 // if effective uid is not root. Perhaps, a more elegant way of doing 2661 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2662 if (geteuid() != 0) { 2663 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2664 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2665 } 2666 ThreadPriorityPolicy = 0; 2667 } 2668 } 2669 if (UseCriticalJavaThreadPriority) { 2670 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2671 } 2672 return 0; 2673} 2674 2675OSReturn os::set_native_priority(Thread* thread, int newpri) { 2676 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2677 2678#ifdef __OpenBSD__ 2679 // OpenBSD pthread_setprio starves low priority threads 2680 return OS_OK; 2681#elif defined(__FreeBSD__) 2682 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2683#elif defined(__APPLE__) || defined(__NetBSD__) 2684 struct sched_param sp; 2685 int policy; 2686 pthread_t self = pthread_self(); 2687 2688 if (pthread_getschedparam(self, &policy, &sp) != 0) 2689 return OS_ERR; 2690 2691 sp.sched_priority = newpri; 2692 if (pthread_setschedparam(self, policy, &sp) != 0) 2693 return OS_ERR; 2694 2695 return OS_OK; 2696#else 2697 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2698 return (ret == 0) ? OS_OK : OS_ERR; 2699#endif 2700} 2701 2702OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2703 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2704 *priority_ptr = java_to_os_priority[NormPriority]; 2705 return OS_OK; 2706 } 2707 2708 errno = 0; 2709#if defined(__OpenBSD__) || defined(__FreeBSD__) 2710 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2711#elif defined(__APPLE__) || defined(__NetBSD__) 2712 int policy; 2713 struct sched_param sp; 2714 2715 pthread_getschedparam(pthread_self(), &policy, &sp); 2716 *priority_ptr = sp.sched_priority; 2717#else 2718 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2719#endif 2720 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2721} 2722 2723// Hint to the underlying OS that a task switch would not be good. 2724// Void return because it's a hint and can fail. 2725void os::hint_no_preempt() {} 2726 2727//////////////////////////////////////////////////////////////////////////////// 2728// suspend/resume support 2729 2730// the low-level signal-based suspend/resume support is a remnant from the 2731// old VM-suspension that used to be for java-suspension, safepoints etc, 2732// within hotspot. Now there is a single use-case for this: 2733// - calling get_thread_pc() on the VMThread by the flat-profiler task 2734// that runs in the watcher thread. 2735// The remaining code is greatly simplified from the more general suspension 2736// code that used to be used. 2737// 2738// The protocol is quite simple: 2739// - suspend: 2740// - sends a signal to the target thread 2741// - polls the suspend state of the osthread using a yield loop 2742// - target thread signal handler (SR_handler) sets suspend state 2743// and blocks in sigsuspend until continued 2744// - resume: 2745// - sets target osthread state to continue 2746// - sends signal to end the sigsuspend loop in the SR_handler 2747// 2748// Note that the SR_lock plays no role in this suspend/resume protocol. 2749// 2750 2751static void resume_clear_context(OSThread *osthread) { 2752 osthread->set_ucontext(NULL); 2753 osthread->set_siginfo(NULL); 2754} 2755 2756static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2757 osthread->set_ucontext(context); 2758 osthread->set_siginfo(siginfo); 2759} 2760 2761// 2762// Handler function invoked when a thread's execution is suspended or 2763// resumed. We have to be careful that only async-safe functions are 2764// called here (Note: most pthread functions are not async safe and 2765// should be avoided.) 2766// 2767// Note: sigwait() is a more natural fit than sigsuspend() from an 2768// interface point of view, but sigwait() prevents the signal hander 2769// from being run. libpthread would get very confused by not having 2770// its signal handlers run and prevents sigwait()'s use with the 2771// mutex granting granting signal. 2772// 2773// Currently only ever called on the VMThread or JavaThread 2774// 2775static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2776 // Save and restore errno to avoid confusing native code with EINTR 2777 // after sigsuspend. 2778 int old_errno = errno; 2779 2780 Thread* thread = Thread::current(); 2781 OSThread* osthread = thread->osthread(); 2782 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2783 2784 os::SuspendResume::State current = osthread->sr.state(); 2785 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2786 suspend_save_context(osthread, siginfo, context); 2787 2788 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2789 os::SuspendResume::State state = osthread->sr.suspended(); 2790 if (state == os::SuspendResume::SR_SUSPENDED) { 2791 sigset_t suspend_set; // signals for sigsuspend() 2792 2793 // get current set of blocked signals and unblock resume signal 2794 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2795 sigdelset(&suspend_set, SR_signum); 2796 2797 sr_semaphore.signal(); 2798 // wait here until we are resumed 2799 while (1) { 2800 sigsuspend(&suspend_set); 2801 2802 os::SuspendResume::State result = osthread->sr.running(); 2803 if (result == os::SuspendResume::SR_RUNNING) { 2804 sr_semaphore.signal(); 2805 break; 2806 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2807 ShouldNotReachHere(); 2808 } 2809 } 2810 2811 } else if (state == os::SuspendResume::SR_RUNNING) { 2812 // request was cancelled, continue 2813 } else { 2814 ShouldNotReachHere(); 2815 } 2816 2817 resume_clear_context(osthread); 2818 } else if (current == os::SuspendResume::SR_RUNNING) { 2819 // request was cancelled, continue 2820 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2821 // ignore 2822 } else { 2823 // ignore 2824 } 2825 2826 errno = old_errno; 2827} 2828 2829 2830static int SR_initialize() { 2831 struct sigaction act; 2832 char *s; 2833 /* Get signal number to use for suspend/resume */ 2834 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2835 int sig = ::strtol(s, 0, 10); 2836 if (sig > 0 || sig < NSIG) { 2837 SR_signum = sig; 2838 } 2839 } 2840 2841 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2842 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2843 2844 sigemptyset(&SR_sigset); 2845 sigaddset(&SR_sigset, SR_signum); 2846 2847 /* Set up signal handler for suspend/resume */ 2848 act.sa_flags = SA_RESTART|SA_SIGINFO; 2849 act.sa_handler = (void (*)(int)) SR_handler; 2850 2851 // SR_signum is blocked by default. 2852 // 4528190 - We also need to block pthread restart signal (32 on all 2853 // supported Bsd platforms). Note that BsdThreads need to block 2854 // this signal for all threads to work properly. So we don't have 2855 // to use hard-coded signal number when setting up the mask. 2856 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2857 2858 if (sigaction(SR_signum, &act, 0) == -1) { 2859 return -1; 2860 } 2861 2862 // Save signal flag 2863 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2864 return 0; 2865} 2866 2867static int sr_notify(OSThread* osthread) { 2868 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2869 assert_status(status == 0, status, "pthread_kill"); 2870 return status; 2871} 2872 2873// "Randomly" selected value for how long we want to spin 2874// before bailing out on suspending a thread, also how often 2875// we send a signal to a thread we want to resume 2876static const int RANDOMLY_LARGE_INTEGER = 1000000; 2877static const int RANDOMLY_LARGE_INTEGER2 = 100; 2878 2879// returns true on success and false on error - really an error is fatal 2880// but this seems the normal response to library errors 2881static bool do_suspend(OSThread* osthread) { 2882 assert(osthread->sr.is_running(), "thread should be running"); 2883 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2884 2885 // mark as suspended and send signal 2886 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2887 // failed to switch, state wasn't running? 2888 ShouldNotReachHere(); 2889 return false; 2890 } 2891 2892 if (sr_notify(osthread) != 0) { 2893 ShouldNotReachHere(); 2894 } 2895 2896 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2897 while (true) { 2898 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2899 break; 2900 } else { 2901 // timeout 2902 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2903 if (cancelled == os::SuspendResume::SR_RUNNING) { 2904 return false; 2905 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2906 // make sure that we consume the signal on the semaphore as well 2907 sr_semaphore.wait(); 2908 break; 2909 } else { 2910 ShouldNotReachHere(); 2911 return false; 2912 } 2913 } 2914 } 2915 2916 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2917 return true; 2918} 2919 2920static void do_resume(OSThread* osthread) { 2921 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2922 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2923 2924 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2925 // failed to switch to WAKEUP_REQUEST 2926 ShouldNotReachHere(); 2927 return; 2928 } 2929 2930 while (true) { 2931 if (sr_notify(osthread) == 0) { 2932 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2933 if (osthread->sr.is_running()) { 2934 return; 2935 } 2936 } 2937 } else { 2938 ShouldNotReachHere(); 2939 } 2940 } 2941 2942 guarantee(osthread->sr.is_running(), "Must be running!"); 2943} 2944 2945/////////////////////////////////////////////////////////////////////////////////// 2946// signal handling (except suspend/resume) 2947 2948// This routine may be used by user applications as a "hook" to catch signals. 2949// The user-defined signal handler must pass unrecognized signals to this 2950// routine, and if it returns true (non-zero), then the signal handler must 2951// return immediately. If the flag "abort_if_unrecognized" is true, then this 2952// routine will never retun false (zero), but instead will execute a VM panic 2953// routine kill the process. 2954// 2955// If this routine returns false, it is OK to call it again. This allows 2956// the user-defined signal handler to perform checks either before or after 2957// the VM performs its own checks. Naturally, the user code would be making 2958// a serious error if it tried to handle an exception (such as a null check 2959// or breakpoint) that the VM was generating for its own correct operation. 2960// 2961// This routine may recognize any of the following kinds of signals: 2962// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2963// It should be consulted by handlers for any of those signals. 2964// 2965// The caller of this routine must pass in the three arguments supplied 2966// to the function referred to in the "sa_sigaction" (not the "sa_handler") 2967// field of the structure passed to sigaction(). This routine assumes that 2968// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2969// 2970// Note that the VM will print warnings if it detects conflicting signal 2971// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2972// 2973extern "C" JNIEXPORT int 2974JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2975 void* ucontext, int abort_if_unrecognized); 2976 2977void signalHandler(int sig, siginfo_t* info, void* uc) { 2978 assert(info != NULL && uc != NULL, "it must be old kernel"); 2979 int orig_errno = errno; // Preserve errno value over signal handler. 2980 JVM_handle_bsd_signal(sig, info, uc, true); 2981 errno = orig_errno; 2982} 2983 2984 2985// This boolean allows users to forward their own non-matching signals 2986// to JVM_handle_bsd_signal, harmlessly. 2987bool os::Bsd::signal_handlers_are_installed = false; 2988 2989// For signal-chaining 2990struct sigaction os::Bsd::sigact[MAXSIGNUM]; 2991unsigned int os::Bsd::sigs = 0; 2992bool os::Bsd::libjsig_is_loaded = false; 2993typedef struct sigaction *(*get_signal_t)(int); 2994get_signal_t os::Bsd::get_signal_action = NULL; 2995 2996struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 2997 struct sigaction *actp = NULL; 2998 2999 if (libjsig_is_loaded) { 3000 // Retrieve the old signal handler from libjsig 3001 actp = (*get_signal_action)(sig); 3002 } 3003 if (actp == NULL) { 3004 // Retrieve the preinstalled signal handler from jvm 3005 actp = get_preinstalled_handler(sig); 3006 } 3007 3008 return actp; 3009} 3010 3011static bool call_chained_handler(struct sigaction *actp, int sig, 3012 siginfo_t *siginfo, void *context) { 3013 // Call the old signal handler 3014 if (actp->sa_handler == SIG_DFL) { 3015 // It's more reasonable to let jvm treat it as an unexpected exception 3016 // instead of taking the default action. 3017 return false; 3018 } else if (actp->sa_handler != SIG_IGN) { 3019 if ((actp->sa_flags & SA_NODEFER) == 0) { 3020 // automaticlly block the signal 3021 sigaddset(&(actp->sa_mask), sig); 3022 } 3023 3024 sa_handler_t hand; 3025 sa_sigaction_t sa; 3026 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3027 // retrieve the chained handler 3028 if (siginfo_flag_set) { 3029 sa = actp->sa_sigaction; 3030 } else { 3031 hand = actp->sa_handler; 3032 } 3033 3034 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3035 actp->sa_handler = SIG_DFL; 3036 } 3037 3038 // try to honor the signal mask 3039 sigset_t oset; 3040 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3041 3042 // call into the chained handler 3043 if (siginfo_flag_set) { 3044 (*sa)(sig, siginfo, context); 3045 } else { 3046 (*hand)(sig); 3047 } 3048 3049 // restore the signal mask 3050 pthread_sigmask(SIG_SETMASK, &oset, 0); 3051 } 3052 // Tell jvm's signal handler the signal is taken care of. 3053 return true; 3054} 3055 3056bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3057 bool chained = false; 3058 // signal-chaining 3059 if (UseSignalChaining) { 3060 struct sigaction *actp = get_chained_signal_action(sig); 3061 if (actp != NULL) { 3062 chained = call_chained_handler(actp, sig, siginfo, context); 3063 } 3064 } 3065 return chained; 3066} 3067 3068struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3069 if ((((unsigned int)1 << sig) & sigs) != 0) { 3070 return &sigact[sig]; 3071 } 3072 return NULL; 3073} 3074 3075void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3076 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3077 sigact[sig] = oldAct; 3078 sigs |= (unsigned int)1 << sig; 3079} 3080 3081// for diagnostic 3082int os::Bsd::sigflags[MAXSIGNUM]; 3083 3084int os::Bsd::get_our_sigflags(int sig) { 3085 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3086 return sigflags[sig]; 3087} 3088 3089void os::Bsd::set_our_sigflags(int sig, int flags) { 3090 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3091 sigflags[sig] = flags; 3092} 3093 3094void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3095 // Check for overwrite. 3096 struct sigaction oldAct; 3097 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3098 3099 void* oldhand = oldAct.sa_sigaction 3100 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3101 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3102 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3103 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3104 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3105 if (AllowUserSignalHandlers || !set_installed) { 3106 // Do not overwrite; user takes responsibility to forward to us. 3107 return; 3108 } else if (UseSignalChaining) { 3109 // save the old handler in jvm 3110 save_preinstalled_handler(sig, oldAct); 3111 // libjsig also interposes the sigaction() call below and saves the 3112 // old sigaction on it own. 3113 } else { 3114 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3115 "%#lx for signal %d.", (long)oldhand, sig)); 3116 } 3117 } 3118 3119 struct sigaction sigAct; 3120 sigfillset(&(sigAct.sa_mask)); 3121 sigAct.sa_handler = SIG_DFL; 3122 if (!set_installed) { 3123 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3124 } else { 3125 sigAct.sa_sigaction = signalHandler; 3126 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3127 } 3128#ifdef __APPLE__ 3129 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3130 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3131 // if the signal handler declares it will handle it on alternate stack. 3132 // Notice we only declare we will handle it on alt stack, but we are not 3133 // actually going to use real alt stack - this is just a workaround. 3134 // Please see ux_exception.c, method catch_mach_exception_raise for details 3135 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3136 if (sig == SIGSEGV) { 3137 sigAct.sa_flags |= SA_ONSTACK; 3138 } 3139#endif 3140 3141 // Save flags, which are set by ours 3142 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3143 sigflags[sig] = sigAct.sa_flags; 3144 3145 int ret = sigaction(sig, &sigAct, &oldAct); 3146 assert(ret == 0, "check"); 3147 3148 void* oldhand2 = oldAct.sa_sigaction 3149 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3150 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3151 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3152} 3153 3154// install signal handlers for signals that HotSpot needs to 3155// handle in order to support Java-level exception handling. 3156 3157void os::Bsd::install_signal_handlers() { 3158 if (!signal_handlers_are_installed) { 3159 signal_handlers_are_installed = true; 3160 3161 // signal-chaining 3162 typedef void (*signal_setting_t)(); 3163 signal_setting_t begin_signal_setting = NULL; 3164 signal_setting_t end_signal_setting = NULL; 3165 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3166 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3167 if (begin_signal_setting != NULL) { 3168 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3169 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3170 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3171 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3172 libjsig_is_loaded = true; 3173 assert(UseSignalChaining, "should enable signal-chaining"); 3174 } 3175 if (libjsig_is_loaded) { 3176 // Tell libjsig jvm is setting signal handlers 3177 (*begin_signal_setting)(); 3178 } 3179 3180 set_signal_handler(SIGSEGV, true); 3181 set_signal_handler(SIGPIPE, true); 3182 set_signal_handler(SIGBUS, true); 3183 set_signal_handler(SIGILL, true); 3184 set_signal_handler(SIGFPE, true); 3185 set_signal_handler(SIGXFSZ, true); 3186 3187#if defined(__APPLE__) 3188 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3189 // signals caught and handled by the JVM. To work around this, we reset the mach task 3190 // signal handler that's placed on our process by CrashReporter. This disables 3191 // CrashReporter-based reporting. 3192 // 3193 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3194 // on caught fatal signals. 3195 // 3196 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3197 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3198 // exception handling, while leaving the standard BSD signal handlers functional. 3199 kern_return_t kr; 3200 kr = task_set_exception_ports(mach_task_self(), 3201 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3202 MACH_PORT_NULL, 3203 EXCEPTION_STATE_IDENTITY, 3204 MACHINE_THREAD_STATE); 3205 3206 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3207#endif 3208 3209 if (libjsig_is_loaded) { 3210 // Tell libjsig jvm finishes setting signal handlers 3211 (*end_signal_setting)(); 3212 } 3213 3214 // We don't activate signal checker if libjsig is in place, we trust ourselves 3215 // and if UserSignalHandler is installed all bets are off 3216 if (CheckJNICalls) { 3217 if (libjsig_is_loaded) { 3218 if (PrintJNIResolving) { 3219 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3220 } 3221 check_signals = false; 3222 } 3223 if (AllowUserSignalHandlers) { 3224 if (PrintJNIResolving) { 3225 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3226 } 3227 check_signals = false; 3228 } 3229 } 3230 } 3231} 3232 3233 3234///// 3235// glibc on Bsd platform uses non-documented flag 3236// to indicate, that some special sort of signal 3237// trampoline is used. 3238// We will never set this flag, and we should 3239// ignore this flag in our diagnostic 3240#ifdef SIGNIFICANT_SIGNAL_MASK 3241#undef SIGNIFICANT_SIGNAL_MASK 3242#endif 3243#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3244 3245static const char* get_signal_handler_name(address handler, 3246 char* buf, int buflen) { 3247 int offset; 3248 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3249 if (found) { 3250 // skip directory names 3251 const char *p1, *p2; 3252 p1 = buf; 3253 size_t len = strlen(os::file_separator()); 3254 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3255 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3256 } else { 3257 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3258 } 3259 return buf; 3260} 3261 3262static void print_signal_handler(outputStream* st, int sig, 3263 char* buf, size_t buflen) { 3264 struct sigaction sa; 3265 3266 sigaction(sig, NULL, &sa); 3267 3268 // See comment for SIGNIFICANT_SIGNAL_MASK define 3269 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3270 3271 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3272 3273 address handler = (sa.sa_flags & SA_SIGINFO) 3274 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3275 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3276 3277 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3278 st->print("SIG_DFL"); 3279 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3280 st->print("SIG_IGN"); 3281 } else { 3282 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3283 } 3284 3285 st->print(", sa_mask[0]="); 3286 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3287 3288 address rh = VMError::get_resetted_sighandler(sig); 3289 // May be, handler was resetted by VMError? 3290 if (rh != NULL) { 3291 handler = rh; 3292 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3293 } 3294 3295 st->print(", sa_flags="); 3296 os::Posix::print_sa_flags(st, sa.sa_flags); 3297 3298 // Check: is it our handler? 3299 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3300 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3301 // It is our signal handler 3302 // check for flags, reset system-used one! 3303 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3304 st->print( 3305 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3306 os::Bsd::get_our_sigflags(sig)); 3307 } 3308 } 3309 st->cr(); 3310} 3311 3312 3313#define DO_SIGNAL_CHECK(sig) \ 3314 if (!sigismember(&check_signal_done, sig)) \ 3315 os::Bsd::check_signal_handler(sig) 3316 3317// This method is a periodic task to check for misbehaving JNI applications 3318// under CheckJNI, we can add any periodic checks here 3319 3320void os::run_periodic_checks() { 3321 3322 if (check_signals == false) return; 3323 3324 // SEGV and BUS if overridden could potentially prevent 3325 // generation of hs*.log in the event of a crash, debugging 3326 // such a case can be very challenging, so we absolutely 3327 // check the following for a good measure: 3328 DO_SIGNAL_CHECK(SIGSEGV); 3329 DO_SIGNAL_CHECK(SIGILL); 3330 DO_SIGNAL_CHECK(SIGFPE); 3331 DO_SIGNAL_CHECK(SIGBUS); 3332 DO_SIGNAL_CHECK(SIGPIPE); 3333 DO_SIGNAL_CHECK(SIGXFSZ); 3334 3335 3336 // ReduceSignalUsage allows the user to override these handlers 3337 // see comments at the very top and jvm_solaris.h 3338 if (!ReduceSignalUsage) { 3339 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3340 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3341 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3342 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3343 } 3344 3345 DO_SIGNAL_CHECK(SR_signum); 3346 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3347} 3348 3349typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3350 3351static os_sigaction_t os_sigaction = NULL; 3352 3353void os::Bsd::check_signal_handler(int sig) { 3354 char buf[O_BUFLEN]; 3355 address jvmHandler = NULL; 3356 3357 3358 struct sigaction act; 3359 if (os_sigaction == NULL) { 3360 // only trust the default sigaction, in case it has been interposed 3361 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3362 if (os_sigaction == NULL) return; 3363 } 3364 3365 os_sigaction(sig, (struct sigaction*)NULL, &act); 3366 3367 3368 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3369 3370 address thisHandler = (act.sa_flags & SA_SIGINFO) 3371 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3372 : CAST_FROM_FN_PTR(address, act.sa_handler); 3373 3374 3375 switch (sig) { 3376 case SIGSEGV: 3377 case SIGBUS: 3378 case SIGFPE: 3379 case SIGPIPE: 3380 case SIGILL: 3381 case SIGXFSZ: 3382 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3383 break; 3384 3385 case SHUTDOWN1_SIGNAL: 3386 case SHUTDOWN2_SIGNAL: 3387 case SHUTDOWN3_SIGNAL: 3388 case BREAK_SIGNAL: 3389 jvmHandler = (address)user_handler(); 3390 break; 3391 3392 case INTERRUPT_SIGNAL: 3393 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3394 break; 3395 3396 default: 3397 if (sig == SR_signum) { 3398 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3399 } else { 3400 return; 3401 } 3402 break; 3403 } 3404 3405 if (thisHandler != jvmHandler) { 3406 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3407 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3408 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3409 // No need to check this sig any longer 3410 sigaddset(&check_signal_done, sig); 3411 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3412 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3413 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3414 exception_name(sig, buf, O_BUFLEN)); 3415 } 3416 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3417 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3418 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3419 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3420 // No need to check this sig any longer 3421 sigaddset(&check_signal_done, sig); 3422 } 3423 3424 // Dump all the signal 3425 if (sigismember(&check_signal_done, sig)) { 3426 print_signal_handlers(tty, buf, O_BUFLEN); 3427 } 3428} 3429 3430extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3431 3432extern bool signal_name(int signo, char* buf, size_t len); 3433 3434const char* os::exception_name(int exception_code, char* buf, size_t size) { 3435 if (0 < exception_code && exception_code <= SIGRTMAX) { 3436 // signal 3437 if (!signal_name(exception_code, buf, size)) { 3438 jio_snprintf(buf, size, "SIG%d", exception_code); 3439 } 3440 return buf; 3441 } else { 3442 return NULL; 3443 } 3444} 3445 3446// this is called _before_ the most of global arguments have been parsed 3447void os::init(void) { 3448 char dummy; /* used to get a guess on initial stack address */ 3449// first_hrtime = gethrtime(); 3450 3451 // With BsdThreads the JavaMain thread pid (primordial thread) 3452 // is different than the pid of the java launcher thread. 3453 // So, on Bsd, the launcher thread pid is passed to the VM 3454 // via the sun.java.launcher.pid property. 3455 // Use this property instead of getpid() if it was correctly passed. 3456 // See bug 6351349. 3457 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3458 3459 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3460 3461 clock_tics_per_sec = CLK_TCK; 3462 3463 init_random(1234567); 3464 3465 ThreadCritical::initialize(); 3466 3467 Bsd::set_page_size(getpagesize()); 3468 if (Bsd::page_size() == -1) { 3469 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3470 strerror(errno))); 3471 } 3472 init_page_sizes((size_t) Bsd::page_size()); 3473 3474 Bsd::initialize_system_info(); 3475 3476 // main_thread points to the aboriginal thread 3477 Bsd::_main_thread = pthread_self(); 3478 3479 Bsd::clock_init(); 3480 initial_time_count = javaTimeNanos(); 3481 3482#ifdef __APPLE__ 3483 // XXXDARWIN 3484 // Work around the unaligned VM callbacks in hotspot's 3485 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3486 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3487 // alignment when doing symbol lookup. To work around this, we force early 3488 // binding of all symbols now, thus binding when alignment is known-good. 3489 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3490#endif 3491} 3492 3493// To install functions for atexit system call 3494extern "C" { 3495 static void perfMemory_exit_helper() { 3496 perfMemory_exit(); 3497 } 3498} 3499 3500// this is called _after_ the global arguments have been parsed 3501jint os::init_2(void) 3502{ 3503 // Allocate a single page and mark it as readable for safepoint polling 3504 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3505 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3506 3507 os::set_polling_page(polling_page); 3508 3509#ifndef PRODUCT 3510 if (Verbose && PrintMiscellaneous) 3511 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3512#endif 3513 3514 if (!UseMembar) { 3515 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3516 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3517 os::set_memory_serialize_page(mem_serialize_page); 3518 3519#ifndef PRODUCT 3520 if (Verbose && PrintMiscellaneous) 3521 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3522#endif 3523 } 3524 3525 // initialize suspend/resume support - must do this before signal_sets_init() 3526 if (SR_initialize() != 0) { 3527 perror("SR_initialize failed"); 3528 return JNI_ERR; 3529 } 3530 3531 Bsd::signal_sets_init(); 3532 Bsd::install_signal_handlers(); 3533 3534 // Check minimum allowable stack size for thread creation and to initialize 3535 // the java system classes, including StackOverflowError - depends on page 3536 // size. Add a page for compiler2 recursion in main thread. 3537 // Add in 2*BytesPerWord times page size to account for VM stack during 3538 // class initialization depending on 32 or 64 bit VM. 3539 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3540 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3541 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3542 3543 size_t threadStackSizeInBytes = ThreadStackSize * K; 3544 if (threadStackSizeInBytes != 0 && 3545 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3546 tty->print_cr("\nThe stack size specified is too small, " 3547 "Specify at least %dk", 3548 os::Bsd::min_stack_allowed/ K); 3549 return JNI_ERR; 3550 } 3551 3552 // Make the stack size a multiple of the page size so that 3553 // the yellow/red zones can be guarded. 3554 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3555 vm_page_size())); 3556 3557 if (MaxFDLimit) { 3558 // set the number of file descriptors to max. print out error 3559 // if getrlimit/setrlimit fails but continue regardless. 3560 struct rlimit nbr_files; 3561 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3562 if (status != 0) { 3563 if (PrintMiscellaneous && (Verbose || WizardMode)) 3564 perror("os::init_2 getrlimit failed"); 3565 } else { 3566 nbr_files.rlim_cur = nbr_files.rlim_max; 3567 3568#ifdef __APPLE__ 3569 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3570 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3571 // be used instead 3572 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3573#endif 3574 3575 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3576 if (status != 0) { 3577 if (PrintMiscellaneous && (Verbose || WizardMode)) 3578 perror("os::init_2 setrlimit failed"); 3579 } 3580 } 3581 } 3582 3583 // at-exit methods are called in the reverse order of their registration. 3584 // atexit functions are called on return from main or as a result of a 3585 // call to exit(3C). There can be only 32 of these functions registered 3586 // and atexit() does not set errno. 3587 3588 if (PerfAllowAtExitRegistration) { 3589 // only register atexit functions if PerfAllowAtExitRegistration is set. 3590 // atexit functions can be delayed until process exit time, which 3591 // can be problematic for embedded VM situations. Embedded VMs should 3592 // call DestroyJavaVM() to assure that VM resources are released. 3593 3594 // note: perfMemory_exit_helper atexit function may be removed in 3595 // the future if the appropriate cleanup code can be added to the 3596 // VM_Exit VMOperation's doit method. 3597 if (atexit(perfMemory_exit_helper) != 0) { 3598 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3599 } 3600 } 3601 3602 // initialize thread priority policy 3603 prio_init(); 3604 3605#ifdef __APPLE__ 3606 // dynamically link to objective c gc registration 3607 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3608 if (handleLibObjc != NULL) { 3609 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3610 } 3611#endif 3612 3613 return JNI_OK; 3614} 3615 3616// this is called at the end of vm_initialization 3617void os::init_3(void) { } 3618 3619// Mark the polling page as unreadable 3620void os::make_polling_page_unreadable(void) { 3621 if (!guard_memory((char*)_polling_page, Bsd::page_size())) 3622 fatal("Could not disable polling page"); 3623}; 3624 3625// Mark the polling page as readable 3626void os::make_polling_page_readable(void) { 3627 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3628 fatal("Could not enable polling page"); 3629 } 3630}; 3631 3632int os::active_processor_count() { 3633 return _processor_count; 3634} 3635 3636void os::set_native_thread_name(const char *name) { 3637#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3638 // This is only supported in Snow Leopard and beyond 3639 if (name != NULL) { 3640 // Add a "Java: " prefix to the name 3641 char buf[MAXTHREADNAMESIZE]; 3642 snprintf(buf, sizeof(buf), "Java: %s", name); 3643 pthread_setname_np(buf); 3644 } 3645#endif 3646} 3647 3648bool os::distribute_processes(uint length, uint* distribution) { 3649 // Not yet implemented. 3650 return false; 3651} 3652 3653bool os::bind_to_processor(uint processor_id) { 3654 // Not yet implemented. 3655 return false; 3656} 3657 3658void os::SuspendedThreadTask::internal_do_task() { 3659 if (do_suspend(_thread->osthread())) { 3660 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3661 do_task(context); 3662 do_resume(_thread->osthread()); 3663 } 3664} 3665 3666/// 3667class PcFetcher : public os::SuspendedThreadTask { 3668public: 3669 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3670 ExtendedPC result(); 3671protected: 3672 void do_task(const os::SuspendedThreadTaskContext& context); 3673private: 3674 ExtendedPC _epc; 3675}; 3676 3677ExtendedPC PcFetcher::result() { 3678 guarantee(is_done(), "task is not done yet."); 3679 return _epc; 3680} 3681 3682void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3683 Thread* thread = context.thread(); 3684 OSThread* osthread = thread->osthread(); 3685 if (osthread->ucontext() != NULL) { 3686 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3687 } else { 3688 // NULL context is unexpected, double-check this is the VMThread 3689 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3690 } 3691} 3692 3693// Suspends the target using the signal mechanism and then grabs the PC before 3694// resuming the target. Used by the flat-profiler only 3695ExtendedPC os::get_thread_pc(Thread* thread) { 3696 // Make sure that it is called by the watcher for the VMThread 3697 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3698 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3699 3700 PcFetcher fetcher(thread); 3701 fetcher.run(); 3702 return fetcher.result(); 3703} 3704 3705int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3706{ 3707 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3708} 3709 3710//////////////////////////////////////////////////////////////////////////////// 3711// debug support 3712 3713bool os::find(address addr, outputStream* st) { 3714 Dl_info dlinfo; 3715 memset(&dlinfo, 0, sizeof(dlinfo)); 3716 if (dladdr(addr, &dlinfo) != 0) { 3717 st->print(PTR_FORMAT ": ", addr); 3718 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3719 st->print("%s+%#x", dlinfo.dli_sname, 3720 addr - (intptr_t)dlinfo.dli_saddr); 3721 } else if (dlinfo.dli_fbase != NULL) { 3722 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3723 } else { 3724 st->print("<absolute address>"); 3725 } 3726 if (dlinfo.dli_fname != NULL) { 3727 st->print(" in %s", dlinfo.dli_fname); 3728 } 3729 if (dlinfo.dli_fbase != NULL) { 3730 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3731 } 3732 st->cr(); 3733 3734 if (Verbose) { 3735 // decode some bytes around the PC 3736 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3737 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3738 address lowest = (address) dlinfo.dli_sname; 3739 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3740 if (begin < lowest) begin = lowest; 3741 Dl_info dlinfo2; 3742 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3743 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3744 end = (address) dlinfo2.dli_saddr; 3745 Disassembler::decode(begin, end, st); 3746 } 3747 return true; 3748 } 3749 return false; 3750} 3751 3752//////////////////////////////////////////////////////////////////////////////// 3753// misc 3754 3755// This does not do anything on Bsd. This is basically a hook for being 3756// able to use structured exception handling (thread-local exception filters) 3757// on, e.g., Win32. 3758void 3759os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3760 JavaCallArguments* args, Thread* thread) { 3761 f(value, method, args, thread); 3762} 3763 3764void os::print_statistics() { 3765} 3766 3767int os::message_box(const char* title, const char* message) { 3768 int i; 3769 fdStream err(defaultStream::error_fd()); 3770 for (i = 0; i < 78; i++) err.print_raw("="); 3771 err.cr(); 3772 err.print_raw_cr(title); 3773 for (i = 0; i < 78; i++) err.print_raw("-"); 3774 err.cr(); 3775 err.print_raw_cr(message); 3776 for (i = 0; i < 78; i++) err.print_raw("="); 3777 err.cr(); 3778 3779 char buf[16]; 3780 // Prevent process from exiting upon "read error" without consuming all CPU 3781 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3782 3783 return buf[0] == 'y' || buf[0] == 'Y'; 3784} 3785 3786int os::stat(const char *path, struct stat *sbuf) { 3787 char pathbuf[MAX_PATH]; 3788 if (strlen(path) > MAX_PATH - 1) { 3789 errno = ENAMETOOLONG; 3790 return -1; 3791 } 3792 os::native_path(strcpy(pathbuf, path)); 3793 return ::stat(pathbuf, sbuf); 3794} 3795 3796bool os::check_heap(bool force) { 3797 return true; 3798} 3799 3800// Is a (classpath) directory empty? 3801bool os::dir_is_empty(const char* path) { 3802 DIR *dir = NULL; 3803 struct dirent *ptr; 3804 3805 dir = opendir(path); 3806 if (dir == NULL) return true; 3807 3808 /* Scan the directory */ 3809 bool result = true; 3810 char buf[sizeof(struct dirent) + MAX_PATH]; 3811 while (result && (ptr = ::readdir(dir)) != NULL) { 3812 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3813 result = false; 3814 } 3815 } 3816 closedir(dir); 3817 return result; 3818} 3819 3820// This code originates from JDK's sysOpen and open64_w 3821// from src/solaris/hpi/src/system_md.c 3822 3823#ifndef O_DELETE 3824#define O_DELETE 0x10000 3825#endif 3826 3827// Open a file. Unlink the file immediately after open returns 3828// if the specified oflag has the O_DELETE flag set. 3829// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3830 3831int os::open(const char *path, int oflag, int mode) { 3832 3833 if (strlen(path) > MAX_PATH - 1) { 3834 errno = ENAMETOOLONG; 3835 return -1; 3836 } 3837 int fd; 3838 int o_delete = (oflag & O_DELETE); 3839 oflag = oflag & ~O_DELETE; 3840 3841 fd = ::open(path, oflag, mode); 3842 if (fd == -1) return -1; 3843 3844 //If the open succeeded, the file might still be a directory 3845 { 3846 struct stat buf; 3847 int ret = ::fstat(fd, &buf); 3848 int st_mode = buf.st_mode; 3849 3850 if (ret != -1) { 3851 if ((st_mode & S_IFMT) == S_IFDIR) { 3852 errno = EISDIR; 3853 ::close(fd); 3854 return -1; 3855 } 3856 } else { 3857 ::close(fd); 3858 return -1; 3859 } 3860 } 3861 3862 /* 3863 * All file descriptors that are opened in the JVM and not 3864 * specifically destined for a subprocess should have the 3865 * close-on-exec flag set. If we don't set it, then careless 3rd 3866 * party native code might fork and exec without closing all 3867 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3868 * UNIXProcess.c), and this in turn might: 3869 * 3870 * - cause end-of-file to fail to be detected on some file 3871 * descriptors, resulting in mysterious hangs, or 3872 * 3873 * - might cause an fopen in the subprocess to fail on a system 3874 * suffering from bug 1085341. 3875 * 3876 * (Yes, the default setting of the close-on-exec flag is a Unix 3877 * design flaw) 3878 * 3879 * See: 3880 * 1085341: 32-bit stdio routines should support file descriptors >255 3881 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3882 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3883 */ 3884#ifdef FD_CLOEXEC 3885 { 3886 int flags = ::fcntl(fd, F_GETFD); 3887 if (flags != -1) 3888 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3889 } 3890#endif 3891 3892 if (o_delete != 0) { 3893 ::unlink(path); 3894 } 3895 return fd; 3896} 3897 3898 3899// create binary file, rewriting existing file if required 3900int os::create_binary_file(const char* path, bool rewrite_existing) { 3901 int oflags = O_WRONLY | O_CREAT; 3902 if (!rewrite_existing) { 3903 oflags |= O_EXCL; 3904 } 3905 return ::open(path, oflags, S_IREAD | S_IWRITE); 3906} 3907 3908// return current position of file pointer 3909jlong os::current_file_offset(int fd) { 3910 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3911} 3912 3913// move file pointer to the specified offset 3914jlong os::seek_to_file_offset(int fd, jlong offset) { 3915 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3916} 3917 3918// This code originates from JDK's sysAvailable 3919// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3920 3921int os::available(int fd, jlong *bytes) { 3922 jlong cur, end; 3923 int mode; 3924 struct stat buf; 3925 3926 if (::fstat(fd, &buf) >= 0) { 3927 mode = buf.st_mode; 3928 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3929 /* 3930 * XXX: is the following call interruptible? If so, this might 3931 * need to go through the INTERRUPT_IO() wrapper as for other 3932 * blocking, interruptible calls in this file. 3933 */ 3934 int n; 3935 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3936 *bytes = n; 3937 return 1; 3938 } 3939 } 3940 } 3941 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3942 return 0; 3943 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3944 return 0; 3945 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3946 return 0; 3947 } 3948 *bytes = end - cur; 3949 return 1; 3950} 3951 3952int os::socket_available(int fd, jint *pbytes) { 3953 if (fd < 0) 3954 return OS_OK; 3955 3956 int ret; 3957 3958 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 3959 3960 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 3961 // is expected to return 0 on failure and 1 on success to the jdk. 3962 3963 return (ret == OS_ERR) ? 0 : 1; 3964} 3965 3966// Map a block of memory. 3967char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3968 char *addr, size_t bytes, bool read_only, 3969 bool allow_exec) { 3970 int prot; 3971 int flags; 3972 3973 if (read_only) { 3974 prot = PROT_READ; 3975 flags = MAP_SHARED; 3976 } else { 3977 prot = PROT_READ | PROT_WRITE; 3978 flags = MAP_PRIVATE; 3979 } 3980 3981 if (allow_exec) { 3982 prot |= PROT_EXEC; 3983 } 3984 3985 if (addr != NULL) { 3986 flags |= MAP_FIXED; 3987 } 3988 3989 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 3990 fd, file_offset); 3991 if (mapped_address == MAP_FAILED) { 3992 return NULL; 3993 } 3994 return mapped_address; 3995} 3996 3997 3998// Remap a block of memory. 3999char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4000 char *addr, size_t bytes, bool read_only, 4001 bool allow_exec) { 4002 // same as map_memory() on this OS 4003 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4004 allow_exec); 4005} 4006 4007 4008// Unmap a block of memory. 4009bool os::pd_unmap_memory(char* addr, size_t bytes) { 4010 return munmap(addr, bytes) == 0; 4011} 4012 4013// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4014// are used by JVM M&M and JVMTI to get user+sys or user CPU time 4015// of a thread. 4016// 4017// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4018// the fast estimate available on the platform. 4019 4020jlong os::current_thread_cpu_time() { 4021#ifdef __APPLE__ 4022 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4023#else 4024 Unimplemented(); 4025 return 0; 4026#endif 4027} 4028 4029jlong os::thread_cpu_time(Thread* thread) { 4030#ifdef __APPLE__ 4031 return os::thread_cpu_time(thread, true /* user + sys */); 4032#else 4033 Unimplemented(); 4034 return 0; 4035#endif 4036} 4037 4038jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4039#ifdef __APPLE__ 4040 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4041#else 4042 Unimplemented(); 4043 return 0; 4044#endif 4045} 4046 4047jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4048#ifdef __APPLE__ 4049 struct thread_basic_info tinfo; 4050 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4051 kern_return_t kr; 4052 thread_t mach_thread; 4053 4054 mach_thread = thread->osthread()->thread_id(); 4055 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4056 if (kr != KERN_SUCCESS) 4057 return -1; 4058 4059 if (user_sys_cpu_time) { 4060 jlong nanos; 4061 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4062 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4063 return nanos; 4064 } else { 4065 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4066 } 4067#else 4068 Unimplemented(); 4069 return 0; 4070#endif 4071} 4072 4073 4074void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4075 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4076 info_ptr->may_skip_backward = false; // elapsed time not wall time 4077 info_ptr->may_skip_forward = false; // elapsed time not wall time 4078 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4079} 4080 4081void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4082 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4083 info_ptr->may_skip_backward = false; // elapsed time not wall time 4084 info_ptr->may_skip_forward = false; // elapsed time not wall time 4085 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4086} 4087 4088bool os::is_thread_cpu_time_supported() { 4089#ifdef __APPLE__ 4090 return true; 4091#else 4092 return false; 4093#endif 4094} 4095 4096// System loadavg support. Returns -1 if load average cannot be obtained. 4097// Bsd doesn't yet have a (official) notion of processor sets, 4098// so just return the system wide load average. 4099int os::loadavg(double loadavg[], int nelem) { 4100 return ::getloadavg(loadavg, nelem); 4101} 4102 4103void os::pause() { 4104 char filename[MAX_PATH]; 4105 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4106 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4107 } else { 4108 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4109 } 4110 4111 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4112 if (fd != -1) { 4113 struct stat buf; 4114 ::close(fd); 4115 while (::stat(filename, &buf) == 0) { 4116 (void)::poll(NULL, 0, 100); 4117 } 4118 } else { 4119 jio_fprintf(stderr, 4120 "Could not open pause file '%s', continuing immediately.\n", filename); 4121 } 4122} 4123 4124 4125// Refer to the comments in os_solaris.cpp park-unpark. 4126// 4127// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4128// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4129// For specifics regarding the bug see GLIBC BUGID 261237 : 4130// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4131// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4132// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4133// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4134// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4135// and monitorenter when we're using 1-0 locking. All those operations may result in 4136// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4137// of libpthread avoids the problem, but isn't practical. 4138// 4139// Possible remedies: 4140// 4141// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4142// This is palliative and probabilistic, however. If the thread is preempted 4143// between the call to compute_abstime() and pthread_cond_timedwait(), more 4144// than the minimum period may have passed, and the abstime may be stale (in the 4145// past) resultin in a hang. Using this technique reduces the odds of a hang 4146// but the JVM is still vulnerable, particularly on heavily loaded systems. 4147// 4148// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4149// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4150// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4151// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4152// thread. 4153// 4154// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4155// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4156// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4157// This also works well. In fact it avoids kernel-level scalability impediments 4158// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4159// timers in a graceful fashion. 4160// 4161// 4. When the abstime value is in the past it appears that control returns 4162// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4163// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4164// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4165// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4166// It may be possible to avoid reinitialization by checking the return 4167// value from pthread_cond_timedwait(). In addition to reinitializing the 4168// condvar we must establish the invariant that cond_signal() is only called 4169// within critical sections protected by the adjunct mutex. This prevents 4170// cond_signal() from "seeing" a condvar that's in the midst of being 4171// reinitialized or that is corrupt. Sadly, this invariant obviates the 4172// desirable signal-after-unlock optimization that avoids futile context switching. 4173// 4174// I'm also concerned that some versions of NTPL might allocate an auxilliary 4175// structure when a condvar is used or initialized. cond_destroy() would 4176// release the helper structure. Our reinitialize-after-timedwait fix 4177// put excessive stress on malloc/free and locks protecting the c-heap. 4178// 4179// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4180// It may be possible to refine (4) by checking the kernel and NTPL verisons 4181// and only enabling the work-around for vulnerable environments. 4182 4183// utility to compute the abstime argument to timedwait: 4184// millis is the relative timeout time 4185// abstime will be the absolute timeout time 4186// TODO: replace compute_abstime() with unpackTime() 4187 4188static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4189 if (millis < 0) millis = 0; 4190 struct timeval now; 4191 int status = gettimeofday(&now, NULL); 4192 assert(status == 0, "gettimeofday"); 4193 jlong seconds = millis / 1000; 4194 millis %= 1000; 4195 if (seconds > 50000000) { // see man cond_timedwait(3T) 4196 seconds = 50000000; 4197 } 4198 abstime->tv_sec = now.tv_sec + seconds; 4199 long usec = now.tv_usec + millis * 1000; 4200 if (usec >= 1000000) { 4201 abstime->tv_sec += 1; 4202 usec -= 1000000; 4203 } 4204 abstime->tv_nsec = usec * 1000; 4205 return abstime; 4206} 4207 4208void os::PlatformEvent::park() { // AKA "down()" 4209 // Invariant: Only the thread associated with the Event/PlatformEvent 4210 // may call park(). 4211 // TODO: assert that _Assoc != NULL or _Assoc == Self 4212 assert(_nParked == 0, "invariant"); 4213 4214 int v; 4215 for (;;) { 4216 v = _Event; 4217 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4218 } 4219 guarantee(v >= 0, "invariant"); 4220 if (v == 0) { 4221 // Do this the hard way by blocking ... 4222 int status = pthread_mutex_lock(_mutex); 4223 assert_status(status == 0, status, "mutex_lock"); 4224 guarantee(_nParked == 0, "invariant"); 4225 ++_nParked; 4226 while (_Event < 0) { 4227 status = pthread_cond_wait(_cond, _mutex); 4228 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4229 // Treat this the same as if the wait was interrupted 4230 if (status == ETIMEDOUT) { status = EINTR; } 4231 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4232 } 4233 --_nParked; 4234 4235 _Event = 0; 4236 status = pthread_mutex_unlock(_mutex); 4237 assert_status(status == 0, status, "mutex_unlock"); 4238 // Paranoia to ensure our locked and lock-free paths interact 4239 // correctly with each other. 4240 OrderAccess::fence(); 4241 } 4242 guarantee(_Event >= 0, "invariant"); 4243} 4244 4245int os::PlatformEvent::park(jlong millis) { 4246 guarantee(_nParked == 0, "invariant"); 4247 4248 int v; 4249 for (;;) { 4250 v = _Event; 4251 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4252 } 4253 guarantee(v >= 0, "invariant"); 4254 if (v != 0) return OS_OK; 4255 4256 // We do this the hard way, by blocking the thread. 4257 // Consider enforcing a minimum timeout value. 4258 struct timespec abst; 4259 compute_abstime(&abst, millis); 4260 4261 int ret = OS_TIMEOUT; 4262 int status = pthread_mutex_lock(_mutex); 4263 assert_status(status == 0, status, "mutex_lock"); 4264 guarantee(_nParked == 0, "invariant"); 4265 ++_nParked; 4266 4267 // Object.wait(timo) will return because of 4268 // (a) notification 4269 // (b) timeout 4270 // (c) thread.interrupt 4271 // 4272 // Thread.interrupt and object.notify{All} both call Event::set. 4273 // That is, we treat thread.interrupt as a special case of notification. 4274 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4275 // We assume all ETIME returns are valid. 4276 // 4277 // TODO: properly differentiate simultaneous notify+interrupt. 4278 // In that case, we should propagate the notify to another waiter. 4279 4280 while (_Event < 0) { 4281 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4282 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4283 pthread_cond_destroy(_cond); 4284 pthread_cond_init(_cond, NULL); 4285 } 4286 assert_status(status == 0 || status == EINTR || 4287 status == ETIMEDOUT, 4288 status, "cond_timedwait"); 4289 if (!FilterSpuriousWakeups) break; // previous semantics 4290 if (status == ETIMEDOUT) break; 4291 // We consume and ignore EINTR and spurious wakeups. 4292 } 4293 --_nParked; 4294 if (_Event >= 0) { 4295 ret = OS_OK; 4296 } 4297 _Event = 0; 4298 status = pthread_mutex_unlock(_mutex); 4299 assert_status(status == 0, status, "mutex_unlock"); 4300 assert(_nParked == 0, "invariant"); 4301 // Paranoia to ensure our locked and lock-free paths interact 4302 // correctly with each other. 4303 OrderAccess::fence(); 4304 return ret; 4305} 4306 4307void os::PlatformEvent::unpark() { 4308 // Transitions for _Event: 4309 // 0 :=> 1 4310 // 1 :=> 1 4311 // -1 :=> either 0 or 1; must signal target thread 4312 // That is, we can safely transition _Event from -1 to either 4313 // 0 or 1. 4314 // See also: "Semaphores in Plan 9" by Mullender & Cox 4315 // 4316 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4317 // that it will take two back-to-back park() calls for the owning 4318 // thread to block. This has the benefit of forcing a spurious return 4319 // from the first park() call after an unpark() call which will help 4320 // shake out uses of park() and unpark() without condition variables. 4321 4322 if (Atomic::xchg(1, &_Event) >= 0) return; 4323 4324 // Wait for the thread associated with the event to vacate 4325 int status = pthread_mutex_lock(_mutex); 4326 assert_status(status == 0, status, "mutex_lock"); 4327 int AnyWaiters = _nParked; 4328 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4329 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4330 AnyWaiters = 0; 4331 pthread_cond_signal(_cond); 4332 } 4333 status = pthread_mutex_unlock(_mutex); 4334 assert_status(status == 0, status, "mutex_unlock"); 4335 if (AnyWaiters != 0) { 4336 status = pthread_cond_signal(_cond); 4337 assert_status(status == 0, status, "cond_signal"); 4338 } 4339 4340 // Note that we signal() _after dropping the lock for "immortal" Events. 4341 // This is safe and avoids a common class of futile wakeups. In rare 4342 // circumstances this can cause a thread to return prematurely from 4343 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4344 // simply re-test the condition and re-park itself. 4345} 4346 4347 4348// JSR166 4349// ------------------------------------------------------- 4350 4351/* 4352 * The solaris and bsd implementations of park/unpark are fairly 4353 * conservative for now, but can be improved. They currently use a 4354 * mutex/condvar pair, plus a a count. 4355 * Park decrements count if > 0, else does a condvar wait. Unpark 4356 * sets count to 1 and signals condvar. Only one thread ever waits 4357 * on the condvar. Contention seen when trying to park implies that someone 4358 * is unparking you, so don't wait. And spurious returns are fine, so there 4359 * is no need to track notifications. 4360 */ 4361 4362#define MAX_SECS 100000000 4363/* 4364 * This code is common to bsd and solaris and will be moved to a 4365 * common place in dolphin. 4366 * 4367 * The passed in time value is either a relative time in nanoseconds 4368 * or an absolute time in milliseconds. Either way it has to be unpacked 4369 * into suitable seconds and nanoseconds components and stored in the 4370 * given timespec structure. 4371 * Given time is a 64-bit value and the time_t used in the timespec is only 4372 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4373 * overflow if times way in the future are given. Further on Solaris versions 4374 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4375 * number of seconds, in abstime, is less than current_time + 100,000,000. 4376 * As it will be 28 years before "now + 100000000" will overflow we can 4377 * ignore overflow and just impose a hard-limit on seconds using the value 4378 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4379 * years from "now". 4380 */ 4381 4382static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4383 assert(time > 0, "convertTime"); 4384 4385 struct timeval now; 4386 int status = gettimeofday(&now, NULL); 4387 assert(status == 0, "gettimeofday"); 4388 4389 time_t max_secs = now.tv_sec + MAX_SECS; 4390 4391 if (isAbsolute) { 4392 jlong secs = time / 1000; 4393 if (secs > max_secs) { 4394 absTime->tv_sec = max_secs; 4395 } 4396 else { 4397 absTime->tv_sec = secs; 4398 } 4399 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4400 } 4401 else { 4402 jlong secs = time / NANOSECS_PER_SEC; 4403 if (secs >= MAX_SECS) { 4404 absTime->tv_sec = max_secs; 4405 absTime->tv_nsec = 0; 4406 } 4407 else { 4408 absTime->tv_sec = now.tv_sec + secs; 4409 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4410 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4411 absTime->tv_nsec -= NANOSECS_PER_SEC; 4412 ++absTime->tv_sec; // note: this must be <= max_secs 4413 } 4414 } 4415 } 4416 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4417 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4418 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4419 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4420} 4421 4422void Parker::park(bool isAbsolute, jlong time) { 4423 // Ideally we'd do something useful while spinning, such 4424 // as calling unpackTime(). 4425 4426 // Optional fast-path check: 4427 // Return immediately if a permit is available. 4428 // We depend on Atomic::xchg() having full barrier semantics 4429 // since we are doing a lock-free update to _counter. 4430 if (Atomic::xchg(0, &_counter) > 0) return; 4431 4432 Thread* thread = Thread::current(); 4433 assert(thread->is_Java_thread(), "Must be JavaThread"); 4434 JavaThread *jt = (JavaThread *)thread; 4435 4436 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4437 // Check interrupt before trying to wait 4438 if (Thread::is_interrupted(thread, false)) { 4439 return; 4440 } 4441 4442 // Next, demultiplex/decode time arguments 4443 struct timespec absTime; 4444 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4445 return; 4446 } 4447 if (time > 0) { 4448 unpackTime(&absTime, isAbsolute, time); 4449 } 4450 4451 4452 // Enter safepoint region 4453 // Beware of deadlocks such as 6317397. 4454 // The per-thread Parker:: mutex is a classic leaf-lock. 4455 // In particular a thread must never block on the Threads_lock while 4456 // holding the Parker:: mutex. If safepoints are pending both the 4457 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4458 ThreadBlockInVM tbivm(jt); 4459 4460 // Don't wait if cannot get lock since interference arises from 4461 // unblocking. Also. check interrupt before trying wait 4462 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4463 return; 4464 } 4465 4466 int status; 4467 if (_counter > 0) { // no wait needed 4468 _counter = 0; 4469 status = pthread_mutex_unlock(_mutex); 4470 assert(status == 0, "invariant"); 4471 // Paranoia to ensure our locked and lock-free paths interact 4472 // correctly with each other and Java-level accesses. 4473 OrderAccess::fence(); 4474 return; 4475 } 4476 4477#ifdef ASSERT 4478 // Don't catch signals while blocked; let the running threads have the signals. 4479 // (This allows a debugger to break into the running thread.) 4480 sigset_t oldsigs; 4481 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4482 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4483#endif 4484 4485 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4486 jt->set_suspend_equivalent(); 4487 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4488 4489 if (time == 0) { 4490 status = pthread_cond_wait(_cond, _mutex); 4491 } else { 4492 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &absTime); 4493 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4494 pthread_cond_destroy(_cond); 4495 pthread_cond_init(_cond, NULL); 4496 } 4497 } 4498 assert_status(status == 0 || status == EINTR || 4499 status == ETIMEDOUT, 4500 status, "cond_timedwait"); 4501 4502#ifdef ASSERT 4503 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4504#endif 4505 4506 _counter = 0; 4507 status = pthread_mutex_unlock(_mutex); 4508 assert_status(status == 0, status, "invariant"); 4509 // Paranoia to ensure our locked and lock-free paths interact 4510 // correctly with each other and Java-level accesses. 4511 OrderAccess::fence(); 4512 4513 // If externally suspended while waiting, re-suspend 4514 if (jt->handle_special_suspend_equivalent_condition()) { 4515 jt->java_suspend_self(); 4516 } 4517} 4518 4519void Parker::unpark() { 4520 int status = pthread_mutex_lock(_mutex); 4521 assert(status == 0, "invariant"); 4522 const int s = _counter; 4523 _counter = 1; 4524 if (s < 1) { 4525 if (WorkAroundNPTLTimedWaitHang) { 4526 status = pthread_cond_signal(_cond); 4527 assert(status == 0, "invariant"); 4528 status = pthread_mutex_unlock(_mutex); 4529 assert(status == 0, "invariant"); 4530 } else { 4531 status = pthread_mutex_unlock(_mutex); 4532 assert(status == 0, "invariant"); 4533 status = pthread_cond_signal(_cond); 4534 assert(status == 0, "invariant"); 4535 } 4536 } else { 4537 pthread_mutex_unlock(_mutex); 4538 assert(status == 0, "invariant"); 4539 } 4540} 4541 4542 4543/* Darwin has no "environ" in a dynamic library. */ 4544#ifdef __APPLE__ 4545#include <crt_externs.h> 4546#define environ (*_NSGetEnviron()) 4547#else 4548extern char** environ; 4549#endif 4550 4551// Run the specified command in a separate process. Return its exit value, 4552// or -1 on failure (e.g. can't fork a new process). 4553// Unlike system(), this function can be called from signal handler. It 4554// doesn't block SIGINT et al. 4555int os::fork_and_exec(char* cmd) { 4556 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4557 4558 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4559 // pthread_atfork handlers and reset pthread library. All we need is a 4560 // separate process to execve. Make a direct syscall to fork process. 4561 // On IA64 there's no fork syscall, we have to use fork() and hope for 4562 // the best... 4563 pid_t pid = fork(); 4564 4565 if (pid < 0) { 4566 // fork failed 4567 return -1; 4568 4569 } else if (pid == 0) { 4570 // child process 4571 4572 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4573 // first to kill every thread on the thread list. Because this list is 4574 // not reset by fork() (see notes above), execve() will instead kill 4575 // every thread in the parent process. We know this is the only thread 4576 // in the new process, so make a system call directly. 4577 // IA64 should use normal execve() from glibc to match the glibc fork() 4578 // above. 4579 execve("/bin/sh", (char* const*)argv, environ); 4580 4581 // execve failed 4582 _exit(-1); 4583 4584 } else { 4585 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4586 // care about the actual exit code, for now. 4587 4588 int status; 4589 4590 // Wait for the child process to exit. This returns immediately if 4591 // the child has already exited. */ 4592 while (waitpid(pid, &status, 0) < 0) { 4593 switch (errno) { 4594 case ECHILD: return 0; 4595 case EINTR: break; 4596 default: return -1; 4597 } 4598 } 4599 4600 if (WIFEXITED(status)) { 4601 // The child exited normally; get its exit code. 4602 return WEXITSTATUS(status); 4603 } else if (WIFSIGNALED(status)) { 4604 // The child exited because of a signal 4605 // The best value to return is 0x80 + signal number, 4606 // because that is what all Unix shells do, and because 4607 // it allows callers to distinguish between process exit and 4608 // process death by signal. 4609 return 0x80 + WTERMSIG(status); 4610 } else { 4611 // Unknown exit code; pass it through 4612 return status; 4613 } 4614 } 4615} 4616 4617// is_headless_jre() 4618// 4619// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4620// in order to report if we are running in a headless jre 4621// 4622// Since JDK8 xawt/libmawt.so was moved into the same directory 4623// as libawt.so, and renamed libawt_xawt.so 4624// 4625bool os::is_headless_jre() { 4626#ifdef __APPLE__ 4627 // We no longer build headless-only on Mac OS X 4628 return false; 4629#else 4630 struct stat statbuf; 4631 char buf[MAXPATHLEN]; 4632 char libmawtpath[MAXPATHLEN]; 4633 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4634 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4635 char *p; 4636 4637 // Get path to libjvm.so 4638 os::jvm_path(buf, sizeof(buf)); 4639 4640 // Get rid of libjvm.so 4641 p = strrchr(buf, '/'); 4642 if (p == NULL) return false; 4643 else *p = '\0'; 4644 4645 // Get rid of client or server 4646 p = strrchr(buf, '/'); 4647 if (p == NULL) return false; 4648 else *p = '\0'; 4649 4650 // check xawt/libmawt.so 4651 strcpy(libmawtpath, buf); 4652 strcat(libmawtpath, xawtstr); 4653 if (::stat(libmawtpath, &statbuf) == 0) return false; 4654 4655 // check libawt_xawt.so 4656 strcpy(libmawtpath, buf); 4657 strcat(libmawtpath, new_xawtstr); 4658 if (::stat(libmawtpath, &statbuf) == 0) return false; 4659 4660 return true; 4661#endif 4662} 4663 4664// Get the default path to the core file 4665// Returns the length of the string 4666int os::get_core_path(char* buffer, size_t bufferSize) { 4667 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4668 4669 // Truncate if theoretical string was longer than bufferSize 4670 n = MIN2(n, (int)bufferSize); 4671 4672 return n; 4673} 4674 4675#ifndef PRODUCT 4676void TestReserveMemorySpecial_test() { 4677 // No tests available for this platform 4678} 4679#endif 4680