os_bsd.cpp revision 7065:3c820b8715c4
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 1647int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) { 1648 outputStream * out = (outputStream *) param; 1649 out->print_cr(PTR_FORMAT " \t%s", base_address, name); 1650 return 0; 1651} 1652 1653void os::print_dll_info(outputStream *st) { 1654 st->print_cr("Dynamic libraries:"); 1655 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) { 1656 st->print_cr("Error: Cannot print dynamic libraries."); 1657 } 1658} 1659 1660int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) { 1661#ifdef RTLD_DI_LINKMAP 1662 Dl_info dli; 1663 void *handle; 1664 Link_map *map; 1665 Link_map *p; 1666 1667 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || 1668 dli.dli_fname == NULL) { 1669 return 1; 1670 } 1671 handle = dlopen(dli.dli_fname, RTLD_LAZY); 1672 if (handle == NULL) { 1673 return 1; 1674 } 1675 dlinfo(handle, RTLD_DI_LINKMAP, &map); 1676 if (map == NULL) { 1677 dlclose(handle); 1678 return 1; 1679 } 1680 1681 while (map->l_prev != NULL) 1682 map = map->l_prev; 1683 1684 while (map != NULL) { 1685 // Value for top_address is returned as 0 since we don't have any information about module size 1686 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) { 1687 dlclose(handle); 1688 return 1; 1689 } 1690 map = map->l_next; 1691 } 1692 1693 dlclose(handle); 1694#elif defined(__APPLE__) 1695 for (uint32_t i = 1; i < _dyld_image_count(); i++) { 1696 // Value for top_address is returned as 0 since we don't have any information about module size 1697 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) { 1698 return 1; 1699 } 1700 } 1701 return 0; 1702#else 1703 return 1; 1704#endif 1705} 1706 1707void os::print_os_info_brief(outputStream* st) { 1708 st->print("Bsd"); 1709 1710 os::Posix::print_uname_info(st); 1711} 1712 1713void os::print_os_info(outputStream* st) { 1714 st->print("OS:"); 1715 st->print("Bsd"); 1716 1717 os::Posix::print_uname_info(st); 1718 1719 os::Posix::print_rlimit_info(st); 1720 1721 os::Posix::print_load_average(st); 1722} 1723 1724void os::pd_print_cpu_info(outputStream* st) { 1725 // Nothing to do for now. 1726} 1727 1728void os::print_memory_info(outputStream* st) { 1729 1730 st->print("Memory:"); 1731 st->print(" %dk page", os::vm_page_size()>>10); 1732 1733 st->print(", physical " UINT64_FORMAT "k", 1734 os::physical_memory() >> 10); 1735 st->print("(" UINT64_FORMAT "k free)", 1736 os::available_memory() >> 10); 1737 st->cr(); 1738 1739 // meminfo 1740 st->print("\n/proc/meminfo:\n"); 1741 _print_ascii_file("/proc/meminfo", st); 1742 st->cr(); 1743} 1744 1745void os::print_siginfo(outputStream* st, void* siginfo) { 1746 const siginfo_t* si = (const siginfo_t*)siginfo; 1747 1748 os::Posix::print_siginfo_brief(st, si); 1749 1750 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 1751 UseSharedSpaces) { 1752 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1753 if (mapinfo->is_in_shared_space(si->si_addr)) { 1754 st->print("\n\nError accessing class data sharing archive." \ 1755 " Mapped file inaccessible during execution, " \ 1756 " possible disk/network problem."); 1757 } 1758 } 1759 st->cr(); 1760} 1761 1762 1763static void print_signal_handler(outputStream* st, int sig, 1764 char* buf, size_t buflen); 1765 1766void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 1767 st->print_cr("Signal Handlers:"); 1768 print_signal_handler(st, SIGSEGV, buf, buflen); 1769 print_signal_handler(st, SIGBUS , buf, buflen); 1770 print_signal_handler(st, SIGFPE , buf, buflen); 1771 print_signal_handler(st, SIGPIPE, buf, buflen); 1772 print_signal_handler(st, SIGXFSZ, buf, buflen); 1773 print_signal_handler(st, SIGILL , buf, buflen); 1774 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 1775 print_signal_handler(st, SR_signum, buf, buflen); 1776 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 1777 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 1778 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 1779 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 1780} 1781 1782static char saved_jvm_path[MAXPATHLEN] = {0}; 1783 1784// Find the full path to the current module, libjvm 1785void os::jvm_path(char *buf, jint buflen) { 1786 // Error checking. 1787 if (buflen < MAXPATHLEN) { 1788 assert(false, "must use a large-enough buffer"); 1789 buf[0] = '\0'; 1790 return; 1791 } 1792 // Lazy resolve the path to current module. 1793 if (saved_jvm_path[0] != 0) { 1794 strcpy(buf, saved_jvm_path); 1795 return; 1796 } 1797 1798 char dli_fname[MAXPATHLEN]; 1799 bool ret = dll_address_to_library_name( 1800 CAST_FROM_FN_PTR(address, os::jvm_path), 1801 dli_fname, sizeof(dli_fname), NULL); 1802 assert(ret, "cannot locate libjvm"); 1803 char *rp = NULL; 1804 if (ret && dli_fname[0] != '\0') { 1805 rp = realpath(dli_fname, buf); 1806 } 1807 if (rp == NULL) 1808 return; 1809 1810 if (Arguments::sun_java_launcher_is_altjvm()) { 1811 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical 1812 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so" 1813 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/" 1814 // appears at the right place in the string, then assume we are 1815 // installed in a JDK and we're done. Otherwise, check for a 1816 // JAVA_HOME environment variable and construct a path to the JVM 1817 // being overridden. 1818 1819 const char *p = buf + strlen(buf) - 1; 1820 for (int count = 0; p > buf && count < 5; ++count) { 1821 for (--p; p > buf && *p != '/'; --p) 1822 /* empty */ ; 1823 } 1824 1825 if (strncmp(p, "/jre/lib/", 9) != 0) { 1826 // Look for JAVA_HOME in the environment. 1827 char* java_home_var = ::getenv("JAVA_HOME"); 1828 if (java_home_var != NULL && java_home_var[0] != 0) { 1829 char* jrelib_p; 1830 int len; 1831 1832 // Check the current module name "libjvm" 1833 p = strrchr(buf, '/'); 1834 assert(strstr(p, "/libjvm") == p, "invalid library name"); 1835 1836 rp = realpath(java_home_var, buf); 1837 if (rp == NULL) 1838 return; 1839 1840 // determine if this is a legacy image or modules image 1841 // modules image doesn't have "jre" subdirectory 1842 len = strlen(buf); 1843 assert(len < buflen, "Ran out of buffer space"); 1844 jrelib_p = buf + len; 1845 1846 // Add the appropriate library subdir 1847 snprintf(jrelib_p, buflen-len, "/jre/lib"); 1848 if (0 != access(buf, F_OK)) { 1849 snprintf(jrelib_p, buflen-len, "/lib"); 1850 } 1851 1852 // Add the appropriate client or server subdir 1853 len = strlen(buf); 1854 jrelib_p = buf + len; 1855 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 1856 if (0 != access(buf, F_OK)) { 1857 snprintf(jrelib_p, buflen-len, "%s", ""); 1858 } 1859 1860 // If the path exists within JAVA_HOME, add the JVM library name 1861 // to complete the path to JVM being overridden. Otherwise fallback 1862 // to the path to the current library. 1863 if (0 == access(buf, F_OK)) { 1864 // Use current module name "libjvm" 1865 len = strlen(buf); 1866 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); 1867 } else { 1868 // Fall back to path of current library 1869 rp = realpath(dli_fname, buf); 1870 if (rp == NULL) 1871 return; 1872 } 1873 } 1874 } 1875 } 1876 1877 strncpy(saved_jvm_path, buf, MAXPATHLEN); 1878} 1879 1880void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 1881 // no prefix required, not even "_" 1882} 1883 1884void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 1885 // no suffix required 1886} 1887 1888//////////////////////////////////////////////////////////////////////////////// 1889// sun.misc.Signal support 1890 1891static volatile jint sigint_count = 0; 1892 1893static void 1894UserHandler(int sig, void *siginfo, void *context) { 1895 // 4511530 - sem_post is serialized and handled by the manager thread. When 1896 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 1897 // don't want to flood the manager thread with sem_post requests. 1898 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 1899 return; 1900 1901 // Ctrl-C is pressed during error reporting, likely because the error 1902 // handler fails to abort. Let VM die immediately. 1903 if (sig == SIGINT && is_error_reported()) { 1904 os::die(); 1905 } 1906 1907 os::signal_notify(sig); 1908} 1909 1910void* os::user_handler() { 1911 return CAST_FROM_FN_PTR(void*, UserHandler); 1912} 1913 1914extern "C" { 1915 typedef void (*sa_handler_t)(int); 1916 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 1917} 1918 1919void* os::signal(int signal_number, void* handler) { 1920 struct sigaction sigAct, oldSigAct; 1921 1922 sigfillset(&(sigAct.sa_mask)); 1923 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 1924 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 1925 1926 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 1927 // -1 means registration failed 1928 return (void *)-1; 1929 } 1930 1931 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 1932} 1933 1934void os::signal_raise(int signal_number) { 1935 ::raise(signal_number); 1936} 1937 1938/* 1939 * The following code is moved from os.cpp for making this 1940 * code platform specific, which it is by its very nature. 1941 */ 1942 1943// Will be modified when max signal is changed to be dynamic 1944int os::sigexitnum_pd() { 1945 return NSIG; 1946} 1947 1948// a counter for each possible signal value 1949static volatile jint pending_signals[NSIG+1] = { 0 }; 1950 1951// Bsd(POSIX) specific hand shaking semaphore. 1952#ifdef __APPLE__ 1953typedef semaphore_t os_semaphore_t; 1954#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 1955#define SEM_WAIT(sem) semaphore_wait(sem) 1956#define SEM_POST(sem) semaphore_signal(sem) 1957#define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) 1958#else 1959typedef sem_t os_semaphore_t; 1960#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 1961#define SEM_WAIT(sem) sem_wait(&sem) 1962#define SEM_POST(sem) sem_post(&sem) 1963#define SEM_DESTROY(sem) sem_destroy(&sem) 1964#endif 1965 1966class Semaphore : public StackObj { 1967 public: 1968 Semaphore(); 1969 ~Semaphore(); 1970 void signal(); 1971 void wait(); 1972 bool trywait(); 1973 bool timedwait(unsigned int sec, int nsec); 1974 private: 1975 jlong currenttime() const; 1976 os_semaphore_t _semaphore; 1977}; 1978 1979Semaphore::Semaphore() : _semaphore(0) { 1980 SEM_INIT(_semaphore, 0); 1981} 1982 1983Semaphore::~Semaphore() { 1984 SEM_DESTROY(_semaphore); 1985} 1986 1987void Semaphore::signal() { 1988 SEM_POST(_semaphore); 1989} 1990 1991void Semaphore::wait() { 1992 SEM_WAIT(_semaphore); 1993} 1994 1995jlong Semaphore::currenttime() const { 1996 struct timeval tv; 1997 gettimeofday(&tv, NULL); 1998 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); 1999} 2000 2001#ifdef __APPLE__ 2002bool Semaphore::trywait() { 2003 return timedwait(0, 0); 2004} 2005 2006bool Semaphore::timedwait(unsigned int sec, int nsec) { 2007 kern_return_t kr = KERN_ABORTED; 2008 mach_timespec_t waitspec; 2009 waitspec.tv_sec = sec; 2010 waitspec.tv_nsec = nsec; 2011 2012 jlong starttime = currenttime(); 2013 2014 kr = semaphore_timedwait(_semaphore, waitspec); 2015 while (kr == KERN_ABORTED) { 2016 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; 2017 2018 jlong current = currenttime(); 2019 jlong passedtime = current - starttime; 2020 2021 if (passedtime >= totalwait) { 2022 waitspec.tv_sec = 0; 2023 waitspec.tv_nsec = 0; 2024 } else { 2025 jlong waittime = totalwait - (current - starttime); 2026 waitspec.tv_sec = waittime / NANOSECS_PER_SEC; 2027 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; 2028 } 2029 2030 kr = semaphore_timedwait(_semaphore, waitspec); 2031 } 2032 2033 return kr == KERN_SUCCESS; 2034} 2035 2036#else 2037 2038bool Semaphore::trywait() { 2039 return sem_trywait(&_semaphore) == 0; 2040} 2041 2042bool Semaphore::timedwait(unsigned int sec, int nsec) { 2043 struct timespec ts; 2044 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); 2045 2046 while (1) { 2047 int result = sem_timedwait(&_semaphore, &ts); 2048 if (result == 0) { 2049 return true; 2050 } else if (errno == EINTR) { 2051 continue; 2052 } else if (errno == ETIMEDOUT) { 2053 return false; 2054 } else { 2055 return false; 2056 } 2057 } 2058} 2059 2060#endif // __APPLE__ 2061 2062static os_semaphore_t sig_sem; 2063static Semaphore sr_semaphore; 2064 2065void os::signal_init_pd() { 2066 // Initialize signal structures 2067 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2068 2069 // Initialize signal semaphore 2070 ::SEM_INIT(sig_sem, 0); 2071} 2072 2073void os::signal_notify(int sig) { 2074 Atomic::inc(&pending_signals[sig]); 2075 ::SEM_POST(sig_sem); 2076} 2077 2078static int check_pending_signals(bool wait) { 2079 Atomic::store(0, &sigint_count); 2080 for (;;) { 2081 for (int i = 0; i < NSIG + 1; i++) { 2082 jint n = pending_signals[i]; 2083 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2084 return i; 2085 } 2086 } 2087 if (!wait) { 2088 return -1; 2089 } 2090 JavaThread *thread = JavaThread::current(); 2091 ThreadBlockInVM tbivm(thread); 2092 2093 bool threadIsSuspended; 2094 do { 2095 thread->set_suspend_equivalent(); 2096 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2097 ::SEM_WAIT(sig_sem); 2098 2099 // were we externally suspended while we were waiting? 2100 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2101 if (threadIsSuspended) { 2102 // 2103 // The semaphore has been incremented, but while we were waiting 2104 // another thread suspended us. We don't want to continue running 2105 // while suspended because that would surprise the thread that 2106 // suspended us. 2107 // 2108 ::SEM_POST(sig_sem); 2109 2110 thread->java_suspend_self(); 2111 } 2112 } while (threadIsSuspended); 2113 } 2114} 2115 2116int os::signal_lookup() { 2117 return check_pending_signals(false); 2118} 2119 2120int os::signal_wait() { 2121 return check_pending_signals(true); 2122} 2123 2124//////////////////////////////////////////////////////////////////////////////// 2125// Virtual Memory 2126 2127int os::vm_page_size() { 2128 // Seems redundant as all get out 2129 assert(os::Bsd::page_size() != -1, "must call os::init"); 2130 return os::Bsd::page_size(); 2131} 2132 2133// Solaris allocates memory by pages. 2134int os::vm_allocation_granularity() { 2135 assert(os::Bsd::page_size() != -1, "must call os::init"); 2136 return os::Bsd::page_size(); 2137} 2138 2139// Rationale behind this function: 2140// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2141// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2142// samples for JITted code. Here we create private executable mapping over the code cache 2143// and then we can use standard (well, almost, as mapping can change) way to provide 2144// info for the reporting script by storing timestamp and location of symbol 2145void bsd_wrap_code(char* base, size_t size) { 2146 static volatile jint cnt = 0; 2147 2148 if (!UseOprofile) { 2149 return; 2150 } 2151 2152 char buf[PATH_MAX + 1]; 2153 int num = Atomic::add(1, &cnt); 2154 2155 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2156 os::get_temp_directory(), os::current_process_id(), num); 2157 unlink(buf); 2158 2159 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2160 2161 if (fd != -1) { 2162 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2163 if (rv != (off_t)-1) { 2164 if (::write(fd, "", 1) == 1) { 2165 mmap(base, size, 2166 PROT_READ|PROT_WRITE|PROT_EXEC, 2167 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2168 } 2169 } 2170 ::close(fd); 2171 unlink(buf); 2172 } 2173} 2174 2175static void warn_fail_commit_memory(char* addr, size_t size, bool exec, 2176 int err) { 2177 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT 2178 ", %d) failed; error='%s' (errno=%d)", addr, size, exec, 2179 strerror(err), err); 2180} 2181 2182// NOTE: Bsd kernel does not really reserve the pages for us. 2183// All it does is to check if there are enough free pages 2184// left at the time of mmap(). This could be a potential 2185// problem. 2186bool os::pd_commit_memory(char* addr, size_t size, bool exec) { 2187 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2188#ifdef __OpenBSD__ 2189 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2190 if (::mprotect(addr, size, prot) == 0) { 2191 return true; 2192 } 2193#else 2194 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2195 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2196 if (res != (uintptr_t) MAP_FAILED) { 2197 return true; 2198 } 2199#endif 2200 2201 // Warn about any commit errors we see in non-product builds just 2202 // in case mmap() doesn't work as described on the man page. 2203 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) 2204 2205 return false; 2206} 2207 2208bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 2209 bool exec) { 2210 // alignment_hint is ignored on this OS 2211 return pd_commit_memory(addr, size, exec); 2212} 2213 2214void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, 2215 const char* mesg) { 2216 assert(mesg != NULL, "mesg must be specified"); 2217 if (!pd_commit_memory(addr, size, exec)) { 2218 // add extra info in product mode for vm_exit_out_of_memory(): 2219 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) 2220 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); 2221 } 2222} 2223 2224void os::pd_commit_memory_or_exit(char* addr, size_t size, 2225 size_t alignment_hint, bool exec, 2226 const char* mesg) { 2227 // alignment_hint is ignored on this OS 2228 pd_commit_memory_or_exit(addr, size, exec, mesg); 2229} 2230 2231void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2232} 2233 2234void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2235 ::madvise(addr, bytes, MADV_DONTNEED); 2236} 2237 2238void os::numa_make_global(char *addr, size_t bytes) { 2239} 2240 2241void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2242} 2243 2244bool os::numa_topology_changed() { return false; } 2245 2246size_t os::numa_get_groups_num() { 2247 return 1; 2248} 2249 2250int os::numa_get_group_id() { 2251 return 0; 2252} 2253 2254size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2255 if (size > 0) { 2256 ids[0] = 0; 2257 return 1; 2258 } 2259 return 0; 2260} 2261 2262bool os::get_page_info(char *start, page_info* info) { 2263 return false; 2264} 2265 2266char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2267 return end; 2268} 2269 2270 2271bool os::pd_uncommit_memory(char* addr, size_t size) { 2272#ifdef __OpenBSD__ 2273 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2274 return ::mprotect(addr, size, PROT_NONE) == 0; 2275#else 2276 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 2277 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 2278 return res != (uintptr_t) MAP_FAILED; 2279#endif 2280} 2281 2282bool os::pd_create_stack_guard_pages(char* addr, size_t size) { 2283 return os::commit_memory(addr, size, !ExecMem); 2284} 2285 2286// If this is a growable mapping, remove the guard pages entirely by 2287// munmap()ping them. If not, just call uncommit_memory(). 2288bool os::remove_stack_guard_pages(char* addr, size_t size) { 2289 return os::uncommit_memory(addr, size); 2290} 2291 2292static address _highest_vm_reserved_address = NULL; 2293 2294// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 2295// at 'requested_addr'. If there are existing memory mappings at the same 2296// location, however, they will be overwritten. If 'fixed' is false, 2297// 'requested_addr' is only treated as a hint, the return value may or 2298// may not start from the requested address. Unlike Bsd mmap(), this 2299// function returns NULL to indicate failure. 2300static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 2301 char * addr; 2302 int flags; 2303 2304 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 2305 if (fixed) { 2306 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 2307 flags |= MAP_FIXED; 2308 } 2309 2310 // Map reserved/uncommitted pages PROT_NONE so we fail early if we 2311 // touch an uncommitted page. Otherwise, the read/write might 2312 // succeed if we have enough swap space to back the physical page. 2313 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, 2314 flags, -1, 0); 2315 2316 if (addr != MAP_FAILED) { 2317 // anon_mmap() should only get called during VM initialization, 2318 // don't need lock (actually we can skip locking even it can be called 2319 // from multiple threads, because _highest_vm_reserved_address is just a 2320 // hint about the upper limit of non-stack memory regions.) 2321 if ((address)addr + bytes > _highest_vm_reserved_address) { 2322 _highest_vm_reserved_address = (address)addr + bytes; 2323 } 2324 } 2325 2326 return addr == MAP_FAILED ? NULL : addr; 2327} 2328 2329// Don't update _highest_vm_reserved_address, because there might be memory 2330// regions above addr + size. If so, releasing a memory region only creates 2331// a hole in the address space, it doesn't help prevent heap-stack collision. 2332// 2333static int anon_munmap(char * addr, size_t size) { 2334 return ::munmap(addr, size) == 0; 2335} 2336 2337char* os::pd_reserve_memory(size_t bytes, char* requested_addr, 2338 size_t alignment_hint) { 2339 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 2340} 2341 2342bool os::pd_release_memory(char* addr, size_t size) { 2343 return anon_munmap(addr, size); 2344} 2345 2346static bool bsd_mprotect(char* addr, size_t size, int prot) { 2347 // Bsd wants the mprotect address argument to be page aligned. 2348 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 2349 2350 // According to SUSv3, mprotect() should only be used with mappings 2351 // established by mmap(), and mmap() always maps whole pages. Unaligned 2352 // 'addr' likely indicates problem in the VM (e.g. trying to change 2353 // protection of malloc'ed or statically allocated memory). Check the 2354 // caller if you hit this assert. 2355 assert(addr == bottom, "sanity check"); 2356 2357 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 2358 return ::mprotect(bottom, size, prot) == 0; 2359} 2360 2361// Set protections specified 2362bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 2363 bool is_committed) { 2364 unsigned int p = 0; 2365 switch (prot) { 2366 case MEM_PROT_NONE: p = PROT_NONE; break; 2367 case MEM_PROT_READ: p = PROT_READ; break; 2368 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 2369 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 2370 default: 2371 ShouldNotReachHere(); 2372 } 2373 // is_committed is unused. 2374 return bsd_mprotect(addr, bytes, p); 2375} 2376 2377bool os::guard_memory(char* addr, size_t size) { 2378 return bsd_mprotect(addr, size, PROT_NONE); 2379} 2380 2381bool os::unguard_memory(char* addr, size_t size) { 2382 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 2383} 2384 2385bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 2386 return false; 2387} 2388 2389// Large page support 2390 2391static size_t _large_page_size = 0; 2392 2393void os::large_page_init() { 2394} 2395 2396 2397char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { 2398 fatal("This code is not used or maintained."); 2399 2400 // "exec" is passed in but not used. Creating the shared image for 2401 // the code cache doesn't have an SHM_X executable permission to check. 2402 assert(UseLargePages && UseSHM, "only for SHM large pages"); 2403 2404 key_t key = IPC_PRIVATE; 2405 char *addr; 2406 2407 bool warn_on_failure = UseLargePages && 2408 (!FLAG_IS_DEFAULT(UseLargePages) || 2409 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 2410 ); 2411 2412 // Create a large shared memory region to attach to based on size. 2413 // Currently, size is the total size of the heap 2414 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 2415 if (shmid == -1) { 2416 // Possible reasons for shmget failure: 2417 // 1. shmmax is too small for Java heap. 2418 // > check shmmax value: cat /proc/sys/kernel/shmmax 2419 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 2420 // 2. not enough large page memory. 2421 // > check available large pages: cat /proc/meminfo 2422 // > increase amount of large pages: 2423 // echo new_value > /proc/sys/vm/nr_hugepages 2424 // Note 1: different Bsd may use different name for this property, 2425 // e.g. on Redhat AS-3 it is "hugetlb_pool". 2426 // Note 2: it's possible there's enough physical memory available but 2427 // they are so fragmented after a long run that they can't 2428 // coalesce into large pages. Try to reserve large pages when 2429 // the system is still "fresh". 2430 if (warn_on_failure) { 2431 warning("Failed to reserve shared memory (errno = %d).", errno); 2432 } 2433 return NULL; 2434 } 2435 2436 // attach to the region 2437 addr = (char*)shmat(shmid, req_addr, 0); 2438 int err = errno; 2439 2440 // Remove shmid. If shmat() is successful, the actual shared memory segment 2441 // will be deleted when it's detached by shmdt() or when the process 2442 // terminates. If shmat() is not successful this will remove the shared 2443 // segment immediately. 2444 shmctl(shmid, IPC_RMID, NULL); 2445 2446 if ((intptr_t)addr == -1) { 2447 if (warn_on_failure) { 2448 warning("Failed to attach shared memory (errno = %d).", err); 2449 } 2450 return NULL; 2451 } 2452 2453 // The memory is committed 2454 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); 2455 2456 return addr; 2457} 2458 2459bool os::release_memory_special(char* base, size_t bytes) { 2460 if (MemTracker::tracking_level() > NMT_minimal) { 2461 Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); 2462 // detaching the SHM segment will also delete it, see reserve_memory_special() 2463 int rslt = shmdt(base); 2464 if (rslt == 0) { 2465 tkr.record((address)base, bytes); 2466 return true; 2467 } else { 2468 return false; 2469 } 2470 } else { 2471 return shmdt(base) == 0; 2472 } 2473} 2474 2475size_t os::large_page_size() { 2476 return _large_page_size; 2477} 2478 2479// HugeTLBFS allows application to commit large page memory on demand; 2480// with SysV SHM the entire memory region must be allocated as shared 2481// memory. 2482bool os::can_commit_large_page_memory() { 2483 return UseHugeTLBFS; 2484} 2485 2486bool os::can_execute_large_page_memory() { 2487 return UseHugeTLBFS; 2488} 2489 2490// Reserve memory at an arbitrary address, only if that area is 2491// available (and not reserved for something else). 2492 2493char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 2494 const int max_tries = 10; 2495 char* base[max_tries]; 2496 size_t size[max_tries]; 2497 const size_t gap = 0x000000; 2498 2499 // Assert only that the size is a multiple of the page size, since 2500 // that's all that mmap requires, and since that's all we really know 2501 // about at this low abstraction level. If we need higher alignment, 2502 // we can either pass an alignment to this method or verify alignment 2503 // in one of the methods further up the call chain. See bug 5044738. 2504 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 2505 2506 // Repeatedly allocate blocks until the block is allocated at the 2507 // right spot. Give up after max_tries. Note that reserve_memory() will 2508 // automatically update _highest_vm_reserved_address if the call is 2509 // successful. The variable tracks the highest memory address every reserved 2510 // by JVM. It is used to detect heap-stack collision if running with 2511 // fixed-stack BsdThreads. Because here we may attempt to reserve more 2512 // space than needed, it could confuse the collision detecting code. To 2513 // solve the problem, save current _highest_vm_reserved_address and 2514 // calculate the correct value before return. 2515 address old_highest = _highest_vm_reserved_address; 2516 2517 // Bsd mmap allows caller to pass an address as hint; give it a try first, 2518 // if kernel honors the hint then we can return immediately. 2519 char * addr = anon_mmap(requested_addr, bytes, false); 2520 if (addr == requested_addr) { 2521 return requested_addr; 2522 } 2523 2524 if (addr != NULL) { 2525 // mmap() is successful but it fails to reserve at the requested address 2526 anon_munmap(addr, bytes); 2527 } 2528 2529 int i; 2530 for (i = 0; i < max_tries; ++i) { 2531 base[i] = reserve_memory(bytes); 2532 2533 if (base[i] != NULL) { 2534 // Is this the block we wanted? 2535 if (base[i] == requested_addr) { 2536 size[i] = bytes; 2537 break; 2538 } 2539 2540 // Does this overlap the block we wanted? Give back the overlapped 2541 // parts and try again. 2542 2543 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 2544 if (top_overlap >= 0 && top_overlap < bytes) { 2545 unmap_memory(base[i], top_overlap); 2546 base[i] += top_overlap; 2547 size[i] = bytes - top_overlap; 2548 } else { 2549 size_t bottom_overlap = base[i] + bytes - requested_addr; 2550 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 2551 unmap_memory(requested_addr, bottom_overlap); 2552 size[i] = bytes - bottom_overlap; 2553 } else { 2554 size[i] = bytes; 2555 } 2556 } 2557 } 2558 } 2559 2560 // Give back the unused reserved pieces. 2561 2562 for (int j = 0; j < i; ++j) { 2563 if (base[j] != NULL) { 2564 unmap_memory(base[j], size[j]); 2565 } 2566 } 2567 2568 if (i < max_tries) { 2569 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 2570 return requested_addr; 2571 } else { 2572 _highest_vm_reserved_address = old_highest; 2573 return NULL; 2574 } 2575} 2576 2577size_t os::read(int fd, void *buf, unsigned int nBytes) { 2578 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 2579} 2580 2581void os::naked_short_sleep(jlong ms) { 2582 struct timespec req; 2583 2584 assert(ms < 1000, "Un-interruptable sleep, short time use only"); 2585 req.tv_sec = 0; 2586 if (ms > 0) { 2587 req.tv_nsec = (ms % 1000) * 1000000; 2588 } 2589 else { 2590 req.tv_nsec = 1; 2591 } 2592 2593 nanosleep(&req, NULL); 2594 2595 return; 2596} 2597 2598// Sleep forever; naked call to OS-specific sleep; use with CAUTION 2599void os::infinite_sleep() { 2600 while (true) { // sleep forever ... 2601 ::sleep(100); // ... 100 seconds at a time 2602 } 2603} 2604 2605// Used to convert frequent JVM_Yield() to nops 2606bool os::dont_yield() { 2607 return DontYieldALot; 2608} 2609 2610void os::naked_yield() { 2611 sched_yield(); 2612} 2613 2614//////////////////////////////////////////////////////////////////////////////// 2615// thread priority support 2616 2617// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 2618// only supports dynamic priority, static priority must be zero. For real-time 2619// applications, Bsd supports SCHED_RR which allows static priority (1-99). 2620// However, for large multi-threaded applications, SCHED_RR is not only slower 2621// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 2622// of 5 runs - Sep 2005). 2623// 2624// The following code actually changes the niceness of kernel-thread/LWP. It 2625// has an assumption that setpriority() only modifies one kernel-thread/LWP, 2626// not the entire user process, and user level threads are 1:1 mapped to kernel 2627// threads. It has always been the case, but could change in the future. For 2628// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 2629// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 2630 2631#if !defined(__APPLE__) 2632int os::java_to_os_priority[CriticalPriority + 1] = { 2633 19, // 0 Entry should never be used 2634 2635 0, // 1 MinPriority 2636 3, // 2 2637 6, // 3 2638 2639 10, // 4 2640 15, // 5 NormPriority 2641 18, // 6 2642 2643 21, // 7 2644 25, // 8 2645 28, // 9 NearMaxPriority 2646 2647 31, // 10 MaxPriority 2648 2649 31 // 11 CriticalPriority 2650}; 2651#else 2652/* Using Mach high-level priority assignments */ 2653int os::java_to_os_priority[CriticalPriority + 1] = { 2654 0, // 0 Entry should never be used (MINPRI_USER) 2655 2656 27, // 1 MinPriority 2657 28, // 2 2658 29, // 3 2659 2660 30, // 4 2661 31, // 5 NormPriority (BASEPRI_DEFAULT) 2662 32, // 6 2663 2664 33, // 7 2665 34, // 8 2666 35, // 9 NearMaxPriority 2667 2668 36, // 10 MaxPriority 2669 2670 36 // 11 CriticalPriority 2671}; 2672#endif 2673 2674static int prio_init() { 2675 if (ThreadPriorityPolicy == 1) { 2676 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 2677 // if effective uid is not root. Perhaps, a more elegant way of doing 2678 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 2679 if (geteuid() != 0) { 2680 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 2681 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 2682 } 2683 ThreadPriorityPolicy = 0; 2684 } 2685 } 2686 if (UseCriticalJavaThreadPriority) { 2687 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 2688 } 2689 return 0; 2690} 2691 2692OSReturn os::set_native_priority(Thread* thread, int newpri) { 2693 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; 2694 2695#ifdef __OpenBSD__ 2696 // OpenBSD pthread_setprio starves low priority threads 2697 return OS_OK; 2698#elif defined(__FreeBSD__) 2699 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 2700#elif defined(__APPLE__) || defined(__NetBSD__) 2701 struct sched_param sp; 2702 int policy; 2703 pthread_t self = pthread_self(); 2704 2705 if (pthread_getschedparam(self, &policy, &sp) != 0) 2706 return OS_ERR; 2707 2708 sp.sched_priority = newpri; 2709 if (pthread_setschedparam(self, policy, &sp) != 0) 2710 return OS_ERR; 2711 2712 return OS_OK; 2713#else 2714 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 2715 return (ret == 0) ? OS_OK : OS_ERR; 2716#endif 2717} 2718 2719OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 2720 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { 2721 *priority_ptr = java_to_os_priority[NormPriority]; 2722 return OS_OK; 2723 } 2724 2725 errno = 0; 2726#if defined(__OpenBSD__) || defined(__FreeBSD__) 2727 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 2728#elif defined(__APPLE__) || defined(__NetBSD__) 2729 int policy; 2730 struct sched_param sp; 2731 2732 pthread_getschedparam(pthread_self(), &policy, &sp); 2733 *priority_ptr = sp.sched_priority; 2734#else 2735 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 2736#endif 2737 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 2738} 2739 2740// Hint to the underlying OS that a task switch would not be good. 2741// Void return because it's a hint and can fail. 2742void os::hint_no_preempt() {} 2743 2744//////////////////////////////////////////////////////////////////////////////// 2745// suspend/resume support 2746 2747// the low-level signal-based suspend/resume support is a remnant from the 2748// old VM-suspension that used to be for java-suspension, safepoints etc, 2749// within hotspot. Now there is a single use-case for this: 2750// - calling get_thread_pc() on the VMThread by the flat-profiler task 2751// that runs in the watcher thread. 2752// The remaining code is greatly simplified from the more general suspension 2753// code that used to be used. 2754// 2755// The protocol is quite simple: 2756// - suspend: 2757// - sends a signal to the target thread 2758// - polls the suspend state of the osthread using a yield loop 2759// - target thread signal handler (SR_handler) sets suspend state 2760// and blocks in sigsuspend until continued 2761// - resume: 2762// - sets target osthread state to continue 2763// - sends signal to end the sigsuspend loop in the SR_handler 2764// 2765// Note that the SR_lock plays no role in this suspend/resume protocol. 2766// 2767 2768static void resume_clear_context(OSThread *osthread) { 2769 osthread->set_ucontext(NULL); 2770 osthread->set_siginfo(NULL); 2771} 2772 2773static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 2774 osthread->set_ucontext(context); 2775 osthread->set_siginfo(siginfo); 2776} 2777 2778// 2779// Handler function invoked when a thread's execution is suspended or 2780// resumed. We have to be careful that only async-safe functions are 2781// called here (Note: most pthread functions are not async safe and 2782// should be avoided.) 2783// 2784// Note: sigwait() is a more natural fit than sigsuspend() from an 2785// interface point of view, but sigwait() prevents the signal hander 2786// from being run. libpthread would get very confused by not having 2787// its signal handlers run and prevents sigwait()'s use with the 2788// mutex granting granting signal. 2789// 2790// Currently only ever called on the VMThread or JavaThread 2791// 2792static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 2793 // Save and restore errno to avoid confusing native code with EINTR 2794 // after sigsuspend. 2795 int old_errno = errno; 2796 2797 Thread* thread = Thread::current(); 2798 OSThread* osthread = thread->osthread(); 2799 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); 2800 2801 os::SuspendResume::State current = osthread->sr.state(); 2802 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { 2803 suspend_save_context(osthread, siginfo, context); 2804 2805 // attempt to switch the state, we assume we had a SUSPEND_REQUEST 2806 os::SuspendResume::State state = osthread->sr.suspended(); 2807 if (state == os::SuspendResume::SR_SUSPENDED) { 2808 sigset_t suspend_set; // signals for sigsuspend() 2809 2810 // get current set of blocked signals and unblock resume signal 2811 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 2812 sigdelset(&suspend_set, SR_signum); 2813 2814 sr_semaphore.signal(); 2815 // wait here until we are resumed 2816 while (1) { 2817 sigsuspend(&suspend_set); 2818 2819 os::SuspendResume::State result = osthread->sr.running(); 2820 if (result == os::SuspendResume::SR_RUNNING) { 2821 sr_semaphore.signal(); 2822 break; 2823 } else if (result != os::SuspendResume::SR_SUSPENDED) { 2824 ShouldNotReachHere(); 2825 } 2826 } 2827 2828 } else if (state == os::SuspendResume::SR_RUNNING) { 2829 // request was cancelled, continue 2830 } else { 2831 ShouldNotReachHere(); 2832 } 2833 2834 resume_clear_context(osthread); 2835 } else if (current == os::SuspendResume::SR_RUNNING) { 2836 // request was cancelled, continue 2837 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { 2838 // ignore 2839 } else { 2840 // ignore 2841 } 2842 2843 errno = old_errno; 2844} 2845 2846 2847static int SR_initialize() { 2848 struct sigaction act; 2849 char *s; 2850 /* Get signal number to use for suspend/resume */ 2851 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 2852 int sig = ::strtol(s, 0, 10); 2853 if (sig > 0 || sig < NSIG) { 2854 SR_signum = sig; 2855 } 2856 } 2857 2858 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 2859 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 2860 2861 sigemptyset(&SR_sigset); 2862 sigaddset(&SR_sigset, SR_signum); 2863 2864 /* Set up signal handler for suspend/resume */ 2865 act.sa_flags = SA_RESTART|SA_SIGINFO; 2866 act.sa_handler = (void (*)(int)) SR_handler; 2867 2868 // SR_signum is blocked by default. 2869 // 4528190 - We also need to block pthread restart signal (32 on all 2870 // supported Bsd platforms). Note that BsdThreads need to block 2871 // this signal for all threads to work properly. So we don't have 2872 // to use hard-coded signal number when setting up the mask. 2873 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 2874 2875 if (sigaction(SR_signum, &act, 0) == -1) { 2876 return -1; 2877 } 2878 2879 // Save signal flag 2880 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 2881 return 0; 2882} 2883 2884static int sr_notify(OSThread* osthread) { 2885 int status = pthread_kill(osthread->pthread_id(), SR_signum); 2886 assert_status(status == 0, status, "pthread_kill"); 2887 return status; 2888} 2889 2890// "Randomly" selected value for how long we want to spin 2891// before bailing out on suspending a thread, also how often 2892// we send a signal to a thread we want to resume 2893static const int RANDOMLY_LARGE_INTEGER = 1000000; 2894static const int RANDOMLY_LARGE_INTEGER2 = 100; 2895 2896// returns true on success and false on error - really an error is fatal 2897// but this seems the normal response to library errors 2898static bool do_suspend(OSThread* osthread) { 2899 assert(osthread->sr.is_running(), "thread should be running"); 2900 assert(!sr_semaphore.trywait(), "semaphore has invalid state"); 2901 2902 // mark as suspended and send signal 2903 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { 2904 // failed to switch, state wasn't running? 2905 ShouldNotReachHere(); 2906 return false; 2907 } 2908 2909 if (sr_notify(osthread) != 0) { 2910 ShouldNotReachHere(); 2911 } 2912 2913 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED 2914 while (true) { 2915 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2916 break; 2917 } else { 2918 // timeout 2919 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); 2920 if (cancelled == os::SuspendResume::SR_RUNNING) { 2921 return false; 2922 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { 2923 // make sure that we consume the signal on the semaphore as well 2924 sr_semaphore.wait(); 2925 break; 2926 } else { 2927 ShouldNotReachHere(); 2928 return false; 2929 } 2930 } 2931 } 2932 2933 guarantee(osthread->sr.is_suspended(), "Must be suspended"); 2934 return true; 2935} 2936 2937static void do_resume(OSThread* osthread) { 2938 assert(osthread->sr.is_suspended(), "thread should be suspended"); 2939 assert(!sr_semaphore.trywait(), "invalid semaphore state"); 2940 2941 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { 2942 // failed to switch to WAKEUP_REQUEST 2943 ShouldNotReachHere(); 2944 return; 2945 } 2946 2947 while (true) { 2948 if (sr_notify(osthread) == 0) { 2949 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { 2950 if (osthread->sr.is_running()) { 2951 return; 2952 } 2953 } 2954 } else { 2955 ShouldNotReachHere(); 2956 } 2957 } 2958 2959 guarantee(osthread->sr.is_running(), "Must be running!"); 2960} 2961 2962/////////////////////////////////////////////////////////////////////////////////// 2963// signal handling (except suspend/resume) 2964 2965// This routine may be used by user applications as a "hook" to catch signals. 2966// The user-defined signal handler must pass unrecognized signals to this 2967// routine, and if it returns true (non-zero), then the signal handler must 2968// return immediately. If the flag "abort_if_unrecognized" is true, then this 2969// routine will never retun false (zero), but instead will execute a VM panic 2970// routine kill the process. 2971// 2972// If this routine returns false, it is OK to call it again. This allows 2973// the user-defined signal handler to perform checks either before or after 2974// the VM performs its own checks. Naturally, the user code would be making 2975// a serious error if it tried to handle an exception (such as a null check 2976// or breakpoint) that the VM was generating for its own correct operation. 2977// 2978// This routine may recognize any of the following kinds of signals: 2979// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 2980// It should be consulted by handlers for any of those signals. 2981// 2982// The caller of this routine must pass in the three arguments supplied 2983// to the function referred to in the "sa_sigaction" (not the "sa_handler") 2984// field of the structure passed to sigaction(). This routine assumes that 2985// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 2986// 2987// Note that the VM will print warnings if it detects conflicting signal 2988// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 2989// 2990extern "C" JNIEXPORT int 2991JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 2992 void* ucontext, int abort_if_unrecognized); 2993 2994void signalHandler(int sig, siginfo_t* info, void* uc) { 2995 assert(info != NULL && uc != NULL, "it must be old kernel"); 2996 int orig_errno = errno; // Preserve errno value over signal handler. 2997 JVM_handle_bsd_signal(sig, info, uc, true); 2998 errno = orig_errno; 2999} 3000 3001 3002// This boolean allows users to forward their own non-matching signals 3003// to JVM_handle_bsd_signal, harmlessly. 3004bool os::Bsd::signal_handlers_are_installed = false; 3005 3006// For signal-chaining 3007struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3008unsigned int os::Bsd::sigs = 0; 3009bool os::Bsd::libjsig_is_loaded = false; 3010typedef struct sigaction *(*get_signal_t)(int); 3011get_signal_t os::Bsd::get_signal_action = NULL; 3012 3013struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3014 struct sigaction *actp = NULL; 3015 3016 if (libjsig_is_loaded) { 3017 // Retrieve the old signal handler from libjsig 3018 actp = (*get_signal_action)(sig); 3019 } 3020 if (actp == NULL) { 3021 // Retrieve the preinstalled signal handler from jvm 3022 actp = get_preinstalled_handler(sig); 3023 } 3024 3025 return actp; 3026} 3027 3028static bool call_chained_handler(struct sigaction *actp, int sig, 3029 siginfo_t *siginfo, void *context) { 3030 // Call the old signal handler 3031 if (actp->sa_handler == SIG_DFL) { 3032 // It's more reasonable to let jvm treat it as an unexpected exception 3033 // instead of taking the default action. 3034 return false; 3035 } else if (actp->sa_handler != SIG_IGN) { 3036 if ((actp->sa_flags & SA_NODEFER) == 0) { 3037 // automaticlly block the signal 3038 sigaddset(&(actp->sa_mask), sig); 3039 } 3040 3041 sa_handler_t hand; 3042 sa_sigaction_t sa; 3043 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 3044 // retrieve the chained handler 3045 if (siginfo_flag_set) { 3046 sa = actp->sa_sigaction; 3047 } else { 3048 hand = actp->sa_handler; 3049 } 3050 3051 if ((actp->sa_flags & SA_RESETHAND) != 0) { 3052 actp->sa_handler = SIG_DFL; 3053 } 3054 3055 // try to honor the signal mask 3056 sigset_t oset; 3057 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 3058 3059 // call into the chained handler 3060 if (siginfo_flag_set) { 3061 (*sa)(sig, siginfo, context); 3062 } else { 3063 (*hand)(sig); 3064 } 3065 3066 // restore the signal mask 3067 pthread_sigmask(SIG_SETMASK, &oset, 0); 3068 } 3069 // Tell jvm's signal handler the signal is taken care of. 3070 return true; 3071} 3072 3073bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 3074 bool chained = false; 3075 // signal-chaining 3076 if (UseSignalChaining) { 3077 struct sigaction *actp = get_chained_signal_action(sig); 3078 if (actp != NULL) { 3079 chained = call_chained_handler(actp, sig, siginfo, context); 3080 } 3081 } 3082 return chained; 3083} 3084 3085struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 3086 if ((((unsigned int)1 << sig) & sigs) != 0) { 3087 return &sigact[sig]; 3088 } 3089 return NULL; 3090} 3091 3092void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 3093 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3094 sigact[sig] = oldAct; 3095 sigs |= (unsigned int)1 << sig; 3096} 3097 3098// for diagnostic 3099int os::Bsd::sigflags[MAXSIGNUM]; 3100 3101int os::Bsd::get_our_sigflags(int sig) { 3102 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3103 return sigflags[sig]; 3104} 3105 3106void os::Bsd::set_our_sigflags(int sig, int flags) { 3107 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3108 sigflags[sig] = flags; 3109} 3110 3111void os::Bsd::set_signal_handler(int sig, bool set_installed) { 3112 // Check for overwrite. 3113 struct sigaction oldAct; 3114 sigaction(sig, (struct sigaction*)NULL, &oldAct); 3115 3116 void* oldhand = oldAct.sa_sigaction 3117 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3118 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3119 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 3120 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 3121 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 3122 if (AllowUserSignalHandlers || !set_installed) { 3123 // Do not overwrite; user takes responsibility to forward to us. 3124 return; 3125 } else if (UseSignalChaining) { 3126 // save the old handler in jvm 3127 save_preinstalled_handler(sig, oldAct); 3128 // libjsig also interposes the sigaction() call below and saves the 3129 // old sigaction on it own. 3130 } else { 3131 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 3132 "%#lx for signal %d.", (long)oldhand, sig)); 3133 } 3134 } 3135 3136 struct sigaction sigAct; 3137 sigfillset(&(sigAct.sa_mask)); 3138 sigAct.sa_handler = SIG_DFL; 3139 if (!set_installed) { 3140 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3141 } else { 3142 sigAct.sa_sigaction = signalHandler; 3143 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 3144 } 3145#ifdef __APPLE__ 3146 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV 3147 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" 3148 // if the signal handler declares it will handle it on alternate stack. 3149 // Notice we only declare we will handle it on alt stack, but we are not 3150 // actually going to use real alt stack - this is just a workaround. 3151 // Please see ux_exception.c, method catch_mach_exception_raise for details 3152 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c 3153 if (sig == SIGSEGV) { 3154 sigAct.sa_flags |= SA_ONSTACK; 3155 } 3156#endif 3157 3158 // Save flags, which are set by ours 3159 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 3160 sigflags[sig] = sigAct.sa_flags; 3161 3162 int ret = sigaction(sig, &sigAct, &oldAct); 3163 assert(ret == 0, "check"); 3164 3165 void* oldhand2 = oldAct.sa_sigaction 3166 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 3167 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 3168 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 3169} 3170 3171// install signal handlers for signals that HotSpot needs to 3172// handle in order to support Java-level exception handling. 3173 3174void os::Bsd::install_signal_handlers() { 3175 if (!signal_handlers_are_installed) { 3176 signal_handlers_are_installed = true; 3177 3178 // signal-chaining 3179 typedef void (*signal_setting_t)(); 3180 signal_setting_t begin_signal_setting = NULL; 3181 signal_setting_t end_signal_setting = NULL; 3182 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3183 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 3184 if (begin_signal_setting != NULL) { 3185 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 3186 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 3187 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 3188 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 3189 libjsig_is_loaded = true; 3190 assert(UseSignalChaining, "should enable signal-chaining"); 3191 } 3192 if (libjsig_is_loaded) { 3193 // Tell libjsig jvm is setting signal handlers 3194 (*begin_signal_setting)(); 3195 } 3196 3197 set_signal_handler(SIGSEGV, true); 3198 set_signal_handler(SIGPIPE, true); 3199 set_signal_handler(SIGBUS, true); 3200 set_signal_handler(SIGILL, true); 3201 set_signal_handler(SIGFPE, true); 3202 set_signal_handler(SIGXFSZ, true); 3203 3204#if defined(__APPLE__) 3205 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 3206 // signals caught and handled by the JVM. To work around this, we reset the mach task 3207 // signal handler that's placed on our process by CrashReporter. This disables 3208 // CrashReporter-based reporting. 3209 // 3210 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 3211 // on caught fatal signals. 3212 // 3213 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 3214 // handlers. By replacing the existing task exception handler, we disable gdb's mach 3215 // exception handling, while leaving the standard BSD signal handlers functional. 3216 kern_return_t kr; 3217 kr = task_set_exception_ports(mach_task_self(), 3218 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 3219 MACH_PORT_NULL, 3220 EXCEPTION_STATE_IDENTITY, 3221 MACHINE_THREAD_STATE); 3222 3223 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 3224#endif 3225 3226 if (libjsig_is_loaded) { 3227 // Tell libjsig jvm finishes setting signal handlers 3228 (*end_signal_setting)(); 3229 } 3230 3231 // We don't activate signal checker if libjsig is in place, we trust ourselves 3232 // and if UserSignalHandler is installed all bets are off 3233 if (CheckJNICalls) { 3234 if (libjsig_is_loaded) { 3235 if (PrintJNIResolving) { 3236 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 3237 } 3238 check_signals = false; 3239 } 3240 if (AllowUserSignalHandlers) { 3241 if (PrintJNIResolving) { 3242 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 3243 } 3244 check_signals = false; 3245 } 3246 } 3247 } 3248} 3249 3250 3251///// 3252// glibc on Bsd platform uses non-documented flag 3253// to indicate, that some special sort of signal 3254// trampoline is used. 3255// We will never set this flag, and we should 3256// ignore this flag in our diagnostic 3257#ifdef SIGNIFICANT_SIGNAL_MASK 3258#undef SIGNIFICANT_SIGNAL_MASK 3259#endif 3260#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 3261 3262static const char* get_signal_handler_name(address handler, 3263 char* buf, int buflen) { 3264 int offset; 3265 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 3266 if (found) { 3267 // skip directory names 3268 const char *p1, *p2; 3269 p1 = buf; 3270 size_t len = strlen(os::file_separator()); 3271 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 3272 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 3273 } else { 3274 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 3275 } 3276 return buf; 3277} 3278 3279static void print_signal_handler(outputStream* st, int sig, 3280 char* buf, size_t buflen) { 3281 struct sigaction sa; 3282 3283 sigaction(sig, NULL, &sa); 3284 3285 // See comment for SIGNIFICANT_SIGNAL_MASK define 3286 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3287 3288 st->print("%s: ", os::exception_name(sig, buf, buflen)); 3289 3290 address handler = (sa.sa_flags & SA_SIGINFO) 3291 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 3292 : CAST_FROM_FN_PTR(address, sa.sa_handler); 3293 3294 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 3295 st->print("SIG_DFL"); 3296 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 3297 st->print("SIG_IGN"); 3298 } else { 3299 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 3300 } 3301 3302 st->print(", sa_mask[0]="); 3303 os::Posix::print_signal_set_short(st, &sa.sa_mask); 3304 3305 address rh = VMError::get_resetted_sighandler(sig); 3306 // May be, handler was resetted by VMError? 3307 if (rh != NULL) { 3308 handler = rh; 3309 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 3310 } 3311 3312 st->print(", sa_flags="); 3313 os::Posix::print_sa_flags(st, sa.sa_flags); 3314 3315 // Check: is it our handler? 3316 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 3317 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 3318 // It is our signal handler 3319 // check for flags, reset system-used one! 3320 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3321 st->print( 3322 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 3323 os::Bsd::get_our_sigflags(sig)); 3324 } 3325 } 3326 st->cr(); 3327} 3328 3329 3330#define DO_SIGNAL_CHECK(sig) \ 3331 if (!sigismember(&check_signal_done, sig)) \ 3332 os::Bsd::check_signal_handler(sig) 3333 3334// This method is a periodic task to check for misbehaving JNI applications 3335// under CheckJNI, we can add any periodic checks here 3336 3337void os::run_periodic_checks() { 3338 3339 if (check_signals == false) return; 3340 3341 // SEGV and BUS if overridden could potentially prevent 3342 // generation of hs*.log in the event of a crash, debugging 3343 // such a case can be very challenging, so we absolutely 3344 // check the following for a good measure: 3345 DO_SIGNAL_CHECK(SIGSEGV); 3346 DO_SIGNAL_CHECK(SIGILL); 3347 DO_SIGNAL_CHECK(SIGFPE); 3348 DO_SIGNAL_CHECK(SIGBUS); 3349 DO_SIGNAL_CHECK(SIGPIPE); 3350 DO_SIGNAL_CHECK(SIGXFSZ); 3351 3352 3353 // ReduceSignalUsage allows the user to override these handlers 3354 // see comments at the very top and jvm_solaris.h 3355 if (!ReduceSignalUsage) { 3356 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 3357 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 3358 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 3359 DO_SIGNAL_CHECK(BREAK_SIGNAL); 3360 } 3361 3362 DO_SIGNAL_CHECK(SR_signum); 3363 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 3364} 3365 3366typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 3367 3368static os_sigaction_t os_sigaction = NULL; 3369 3370void os::Bsd::check_signal_handler(int sig) { 3371 char buf[O_BUFLEN]; 3372 address jvmHandler = NULL; 3373 3374 3375 struct sigaction act; 3376 if (os_sigaction == NULL) { 3377 // only trust the default sigaction, in case it has been interposed 3378 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 3379 if (os_sigaction == NULL) return; 3380 } 3381 3382 os_sigaction(sig, (struct sigaction*)NULL, &act); 3383 3384 3385 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 3386 3387 address thisHandler = (act.sa_flags & SA_SIGINFO) 3388 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 3389 : CAST_FROM_FN_PTR(address, act.sa_handler); 3390 3391 3392 switch (sig) { 3393 case SIGSEGV: 3394 case SIGBUS: 3395 case SIGFPE: 3396 case SIGPIPE: 3397 case SIGILL: 3398 case SIGXFSZ: 3399 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 3400 break; 3401 3402 case SHUTDOWN1_SIGNAL: 3403 case SHUTDOWN2_SIGNAL: 3404 case SHUTDOWN3_SIGNAL: 3405 case BREAK_SIGNAL: 3406 jvmHandler = (address)user_handler(); 3407 break; 3408 3409 case INTERRUPT_SIGNAL: 3410 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 3411 break; 3412 3413 default: 3414 if (sig == SR_signum) { 3415 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 3416 } else { 3417 return; 3418 } 3419 break; 3420 } 3421 3422 if (thisHandler != jvmHandler) { 3423 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 3424 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 3425 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 3426 // No need to check this sig any longer 3427 sigaddset(&check_signal_done, sig); 3428 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN 3429 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { 3430 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", 3431 exception_name(sig, buf, O_BUFLEN)); 3432 } 3433 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 3434 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 3435 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 3436 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 3437 // No need to check this sig any longer 3438 sigaddset(&check_signal_done, sig); 3439 } 3440 3441 // Dump all the signal 3442 if (sigismember(&check_signal_done, sig)) { 3443 print_signal_handlers(tty, buf, O_BUFLEN); 3444 } 3445} 3446 3447extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 3448 3449extern bool signal_name(int signo, char* buf, size_t len); 3450 3451const char* os::exception_name(int exception_code, char* buf, size_t size) { 3452 if (0 < exception_code && exception_code <= SIGRTMAX) { 3453 // signal 3454 if (!signal_name(exception_code, buf, size)) { 3455 jio_snprintf(buf, size, "SIG%d", exception_code); 3456 } 3457 return buf; 3458 } else { 3459 return NULL; 3460 } 3461} 3462 3463// this is called _before_ the most of global arguments have been parsed 3464void os::init(void) { 3465 char dummy; /* used to get a guess on initial stack address */ 3466// first_hrtime = gethrtime(); 3467 3468 // With BsdThreads the JavaMain thread pid (primordial thread) 3469 // is different than the pid of the java launcher thread. 3470 // So, on Bsd, the launcher thread pid is passed to the VM 3471 // via the sun.java.launcher.pid property. 3472 // Use this property instead of getpid() if it was correctly passed. 3473 // See bug 6351349. 3474 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 3475 3476 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 3477 3478 clock_tics_per_sec = CLK_TCK; 3479 3480 init_random(1234567); 3481 3482 ThreadCritical::initialize(); 3483 3484 Bsd::set_page_size(getpagesize()); 3485 if (Bsd::page_size() == -1) { 3486 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 3487 strerror(errno))); 3488 } 3489 init_page_sizes((size_t) Bsd::page_size()); 3490 3491 Bsd::initialize_system_info(); 3492 3493 // main_thread points to the aboriginal thread 3494 Bsd::_main_thread = pthread_self(); 3495 3496 Bsd::clock_init(); 3497 initial_time_count = javaTimeNanos(); 3498 3499#ifdef __APPLE__ 3500 // XXXDARWIN 3501 // Work around the unaligned VM callbacks in hotspot's 3502 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 3503 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 3504 // alignment when doing symbol lookup. To work around this, we force early 3505 // binding of all symbols now, thus binding when alignment is known-good. 3506 _dyld_bind_fully_image_containing_address((const void *) &os::init); 3507#endif 3508} 3509 3510// To install functions for atexit system call 3511extern "C" { 3512 static void perfMemory_exit_helper() { 3513 perfMemory_exit(); 3514 } 3515} 3516 3517// this is called _after_ the global arguments have been parsed 3518jint os::init_2(void) 3519{ 3520 // Allocate a single page and mark it as readable for safepoint polling 3521 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3522 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); 3523 3524 os::set_polling_page(polling_page); 3525 3526#ifndef PRODUCT 3527 if (Verbose && PrintMiscellaneous) 3528 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 3529#endif 3530 3531 if (!UseMembar) { 3532 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 3533 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); 3534 os::set_memory_serialize_page(mem_serialize_page); 3535 3536#ifndef PRODUCT 3537 if (Verbose && PrintMiscellaneous) 3538 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 3539#endif 3540 } 3541 3542 // initialize suspend/resume support - must do this before signal_sets_init() 3543 if (SR_initialize() != 0) { 3544 perror("SR_initialize failed"); 3545 return JNI_ERR; 3546 } 3547 3548 Bsd::signal_sets_init(); 3549 Bsd::install_signal_handlers(); 3550 3551 // Check minimum allowable stack size for thread creation and to initialize 3552 // the java system classes, including StackOverflowError - depends on page 3553 // size. Add a page for compiler2 recursion in main thread. 3554 // Add in 2*BytesPerWord times page size to account for VM stack during 3555 // class initialization depending on 32 or 64 bit VM. 3556 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 3557 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 3558 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 3559 3560 size_t threadStackSizeInBytes = ThreadStackSize * K; 3561 if (threadStackSizeInBytes != 0 && 3562 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 3563 tty->print_cr("\nThe stack size specified is too small, " 3564 "Specify at least %dk", 3565 os::Bsd::min_stack_allowed/ K); 3566 return JNI_ERR; 3567 } 3568 3569 // Make the stack size a multiple of the page size so that 3570 // the yellow/red zones can be guarded. 3571 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 3572 vm_page_size())); 3573 3574 if (MaxFDLimit) { 3575 // set the number of file descriptors to max. print out error 3576 // if getrlimit/setrlimit fails but continue regardless. 3577 struct rlimit nbr_files; 3578 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 3579 if (status != 0) { 3580 if (PrintMiscellaneous && (Verbose || WizardMode)) 3581 perror("os::init_2 getrlimit failed"); 3582 } else { 3583 nbr_files.rlim_cur = nbr_files.rlim_max; 3584 3585#ifdef __APPLE__ 3586 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 3587 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 3588 // be used instead 3589 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 3590#endif 3591 3592 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 3593 if (status != 0) { 3594 if (PrintMiscellaneous && (Verbose || WizardMode)) 3595 perror("os::init_2 setrlimit failed"); 3596 } 3597 } 3598 } 3599 3600 // at-exit methods are called in the reverse order of their registration. 3601 // atexit functions are called on return from main or as a result of a 3602 // call to exit(3C). There can be only 32 of these functions registered 3603 // and atexit() does not set errno. 3604 3605 if (PerfAllowAtExitRegistration) { 3606 // only register atexit functions if PerfAllowAtExitRegistration is set. 3607 // atexit functions can be delayed until process exit time, which 3608 // can be problematic for embedded VM situations. Embedded VMs should 3609 // call DestroyJavaVM() to assure that VM resources are released. 3610 3611 // note: perfMemory_exit_helper atexit function may be removed in 3612 // the future if the appropriate cleanup code can be added to the 3613 // VM_Exit VMOperation's doit method. 3614 if (atexit(perfMemory_exit_helper) != 0) { 3615 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 3616 } 3617 } 3618 3619 // initialize thread priority policy 3620 prio_init(); 3621 3622#ifdef __APPLE__ 3623 // dynamically link to objective c gc registration 3624 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 3625 if (handleLibObjc != NULL) { 3626 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 3627 } 3628#endif 3629 3630 return JNI_OK; 3631} 3632 3633// this is called at the end of vm_initialization 3634void os::init_3(void) { } 3635 3636// Mark the polling page as unreadable 3637void os::make_polling_page_unreadable(void) { 3638 if (!guard_memory((char*)_polling_page, Bsd::page_size())) 3639 fatal("Could not disable polling page"); 3640}; 3641 3642// Mark the polling page as readable 3643void os::make_polling_page_readable(void) { 3644 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 3645 fatal("Could not enable polling page"); 3646 } 3647}; 3648 3649int os::active_processor_count() { 3650 return _processor_count; 3651} 3652 3653void os::set_native_thread_name(const char *name) { 3654#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 3655 // This is only supported in Snow Leopard and beyond 3656 if (name != NULL) { 3657 // Add a "Java: " prefix to the name 3658 char buf[MAXTHREADNAMESIZE]; 3659 snprintf(buf, sizeof(buf), "Java: %s", name); 3660 pthread_setname_np(buf); 3661 } 3662#endif 3663} 3664 3665bool os::distribute_processes(uint length, uint* distribution) { 3666 // Not yet implemented. 3667 return false; 3668} 3669 3670bool os::bind_to_processor(uint processor_id) { 3671 // Not yet implemented. 3672 return false; 3673} 3674 3675void os::SuspendedThreadTask::internal_do_task() { 3676 if (do_suspend(_thread->osthread())) { 3677 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); 3678 do_task(context); 3679 do_resume(_thread->osthread()); 3680 } 3681} 3682 3683/// 3684class PcFetcher : public os::SuspendedThreadTask { 3685public: 3686 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} 3687 ExtendedPC result(); 3688protected: 3689 void do_task(const os::SuspendedThreadTaskContext& context); 3690private: 3691 ExtendedPC _epc; 3692}; 3693 3694ExtendedPC PcFetcher::result() { 3695 guarantee(is_done(), "task is not done yet."); 3696 return _epc; 3697} 3698 3699void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { 3700 Thread* thread = context.thread(); 3701 OSThread* osthread = thread->osthread(); 3702 if (osthread->ucontext() != NULL) { 3703 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); 3704 } else { 3705 // NULL context is unexpected, double-check this is the VMThread 3706 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 3707 } 3708} 3709 3710// Suspends the target using the signal mechanism and then grabs the PC before 3711// resuming the target. Used by the flat-profiler only 3712ExtendedPC os::get_thread_pc(Thread* thread) { 3713 // Make sure that it is called by the watcher for the VMThread 3714 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 3715 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 3716 3717 PcFetcher fetcher(thread); 3718 fetcher.run(); 3719 return fetcher.result(); 3720} 3721 3722int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 3723{ 3724 return pthread_cond_timedwait(_cond, _mutex, _abstime); 3725} 3726 3727//////////////////////////////////////////////////////////////////////////////// 3728// debug support 3729 3730bool os::find(address addr, outputStream* st) { 3731 Dl_info dlinfo; 3732 memset(&dlinfo, 0, sizeof(dlinfo)); 3733 if (dladdr(addr, &dlinfo) != 0) { 3734 st->print(PTR_FORMAT ": ", addr); 3735 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { 3736 st->print("%s+%#x", dlinfo.dli_sname, 3737 addr - (intptr_t)dlinfo.dli_saddr); 3738 } else if (dlinfo.dli_fbase != NULL) { 3739 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 3740 } else { 3741 st->print("<absolute address>"); 3742 } 3743 if (dlinfo.dli_fname != NULL) { 3744 st->print(" in %s", dlinfo.dli_fname); 3745 } 3746 if (dlinfo.dli_fbase != NULL) { 3747 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 3748 } 3749 st->cr(); 3750 3751 if (Verbose) { 3752 // decode some bytes around the PC 3753 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); 3754 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); 3755 address lowest = (address) dlinfo.dli_sname; 3756 if (!lowest) lowest = (address) dlinfo.dli_fbase; 3757 if (begin < lowest) begin = lowest; 3758 Dl_info dlinfo2; 3759 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr 3760 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 3761 end = (address) dlinfo2.dli_saddr; 3762 Disassembler::decode(begin, end, st); 3763 } 3764 return true; 3765 } 3766 return false; 3767} 3768 3769//////////////////////////////////////////////////////////////////////////////// 3770// misc 3771 3772// This does not do anything on Bsd. This is basically a hook for being 3773// able to use structured exception handling (thread-local exception filters) 3774// on, e.g., Win32. 3775void 3776os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 3777 JavaCallArguments* args, Thread* thread) { 3778 f(value, method, args, thread); 3779} 3780 3781void os::print_statistics() { 3782} 3783 3784int os::message_box(const char* title, const char* message) { 3785 int i; 3786 fdStream err(defaultStream::error_fd()); 3787 for (i = 0; i < 78; i++) err.print_raw("="); 3788 err.cr(); 3789 err.print_raw_cr(title); 3790 for (i = 0; i < 78; i++) err.print_raw("-"); 3791 err.cr(); 3792 err.print_raw_cr(message); 3793 for (i = 0; i < 78; i++) err.print_raw("="); 3794 err.cr(); 3795 3796 char buf[16]; 3797 // Prevent process from exiting upon "read error" without consuming all CPU 3798 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 3799 3800 return buf[0] == 'y' || buf[0] == 'Y'; 3801} 3802 3803int os::stat(const char *path, struct stat *sbuf) { 3804 char pathbuf[MAX_PATH]; 3805 if (strlen(path) > MAX_PATH - 1) { 3806 errno = ENAMETOOLONG; 3807 return -1; 3808 } 3809 os::native_path(strcpy(pathbuf, path)); 3810 return ::stat(pathbuf, sbuf); 3811} 3812 3813bool os::check_heap(bool force) { 3814 return true; 3815} 3816 3817// Is a (classpath) directory empty? 3818bool os::dir_is_empty(const char* path) { 3819 DIR *dir = NULL; 3820 struct dirent *ptr; 3821 3822 dir = opendir(path); 3823 if (dir == NULL) return true; 3824 3825 /* Scan the directory */ 3826 bool result = true; 3827 char buf[sizeof(struct dirent) + MAX_PATH]; 3828 while (result && (ptr = ::readdir(dir)) != NULL) { 3829 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 3830 result = false; 3831 } 3832 } 3833 closedir(dir); 3834 return result; 3835} 3836 3837// This code originates from JDK's sysOpen and open64_w 3838// from src/solaris/hpi/src/system_md.c 3839 3840#ifndef O_DELETE 3841#define O_DELETE 0x10000 3842#endif 3843 3844// Open a file. Unlink the file immediately after open returns 3845// if the specified oflag has the O_DELETE flag set. 3846// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 3847 3848int os::open(const char *path, int oflag, int mode) { 3849 3850 if (strlen(path) > MAX_PATH - 1) { 3851 errno = ENAMETOOLONG; 3852 return -1; 3853 } 3854 int fd; 3855 int o_delete = (oflag & O_DELETE); 3856 oflag = oflag & ~O_DELETE; 3857 3858 fd = ::open(path, oflag, mode); 3859 if (fd == -1) return -1; 3860 3861 //If the open succeeded, the file might still be a directory 3862 { 3863 struct stat buf; 3864 int ret = ::fstat(fd, &buf); 3865 int st_mode = buf.st_mode; 3866 3867 if (ret != -1) { 3868 if ((st_mode & S_IFMT) == S_IFDIR) { 3869 errno = EISDIR; 3870 ::close(fd); 3871 return -1; 3872 } 3873 } else { 3874 ::close(fd); 3875 return -1; 3876 } 3877 } 3878 3879 /* 3880 * All file descriptors that are opened in the JVM and not 3881 * specifically destined for a subprocess should have the 3882 * close-on-exec flag set. If we don't set it, then careless 3rd 3883 * party native code might fork and exec without closing all 3884 * appropriate file descriptors (e.g. as we do in closeDescriptors in 3885 * UNIXProcess.c), and this in turn might: 3886 * 3887 * - cause end-of-file to fail to be detected on some file 3888 * descriptors, resulting in mysterious hangs, or 3889 * 3890 * - might cause an fopen in the subprocess to fail on a system 3891 * suffering from bug 1085341. 3892 * 3893 * (Yes, the default setting of the close-on-exec flag is a Unix 3894 * design flaw) 3895 * 3896 * See: 3897 * 1085341: 32-bit stdio routines should support file descriptors >255 3898 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 3899 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 3900 */ 3901#ifdef FD_CLOEXEC 3902 { 3903 int flags = ::fcntl(fd, F_GETFD); 3904 if (flags != -1) 3905 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 3906 } 3907#endif 3908 3909 if (o_delete != 0) { 3910 ::unlink(path); 3911 } 3912 return fd; 3913} 3914 3915 3916// create binary file, rewriting existing file if required 3917int os::create_binary_file(const char* path, bool rewrite_existing) { 3918 int oflags = O_WRONLY | O_CREAT; 3919 if (!rewrite_existing) { 3920 oflags |= O_EXCL; 3921 } 3922 return ::open(path, oflags, S_IREAD | S_IWRITE); 3923} 3924 3925// return current position of file pointer 3926jlong os::current_file_offset(int fd) { 3927 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 3928} 3929 3930// move file pointer to the specified offset 3931jlong os::seek_to_file_offset(int fd, jlong offset) { 3932 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 3933} 3934 3935// This code originates from JDK's sysAvailable 3936// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 3937 3938int os::available(int fd, jlong *bytes) { 3939 jlong cur, end; 3940 int mode; 3941 struct stat buf; 3942 3943 if (::fstat(fd, &buf) >= 0) { 3944 mode = buf.st_mode; 3945 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 3946 /* 3947 * XXX: is the following call interruptible? If so, this might 3948 * need to go through the INTERRUPT_IO() wrapper as for other 3949 * blocking, interruptible calls in this file. 3950 */ 3951 int n; 3952 if (::ioctl(fd, FIONREAD, &n) >= 0) { 3953 *bytes = n; 3954 return 1; 3955 } 3956 } 3957 } 3958 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 3959 return 0; 3960 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 3961 return 0; 3962 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 3963 return 0; 3964 } 3965 *bytes = end - cur; 3966 return 1; 3967} 3968 3969int os::socket_available(int fd, jint *pbytes) { 3970 if (fd < 0) 3971 return OS_OK; 3972 3973 int ret; 3974 3975 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 3976 3977 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 3978 // is expected to return 0 on failure and 1 on success to the jdk. 3979 3980 return (ret == OS_ERR) ? 0 : 1; 3981} 3982 3983// Map a block of memory. 3984char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, 3985 char *addr, size_t bytes, bool read_only, 3986 bool allow_exec) { 3987 int prot; 3988 int flags; 3989 3990 if (read_only) { 3991 prot = PROT_READ; 3992 flags = MAP_SHARED; 3993 } else { 3994 prot = PROT_READ | PROT_WRITE; 3995 flags = MAP_PRIVATE; 3996 } 3997 3998 if (allow_exec) { 3999 prot |= PROT_EXEC; 4000 } 4001 4002 if (addr != NULL) { 4003 flags |= MAP_FIXED; 4004 } 4005 4006 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 4007 fd, file_offset); 4008 if (mapped_address == MAP_FAILED) { 4009 return NULL; 4010 } 4011 return mapped_address; 4012} 4013 4014 4015// Remap a block of memory. 4016char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, 4017 char *addr, size_t bytes, bool read_only, 4018 bool allow_exec) { 4019 // same as map_memory() on this OS 4020 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 4021 allow_exec); 4022} 4023 4024 4025// Unmap a block of memory. 4026bool os::pd_unmap_memory(char* addr, size_t bytes) { 4027 return munmap(addr, bytes) == 0; 4028} 4029 4030// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 4031// are used by JVM M&M and JVMTI to get user+sys or user CPU time 4032// of a thread. 4033// 4034// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 4035// the fast estimate available on the platform. 4036 4037jlong os::current_thread_cpu_time() { 4038#ifdef __APPLE__ 4039 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 4040#else 4041 Unimplemented(); 4042 return 0; 4043#endif 4044} 4045 4046jlong os::thread_cpu_time(Thread* thread) { 4047#ifdef __APPLE__ 4048 return os::thread_cpu_time(thread, true /* user + sys */); 4049#else 4050 Unimplemented(); 4051 return 0; 4052#endif 4053} 4054 4055jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 4056#ifdef __APPLE__ 4057 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 4058#else 4059 Unimplemented(); 4060 return 0; 4061#endif 4062} 4063 4064jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 4065#ifdef __APPLE__ 4066 struct thread_basic_info tinfo; 4067 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 4068 kern_return_t kr; 4069 thread_t mach_thread; 4070 4071 mach_thread = thread->osthread()->thread_id(); 4072 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 4073 if (kr != KERN_SUCCESS) 4074 return -1; 4075 4076 if (user_sys_cpu_time) { 4077 jlong nanos; 4078 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 4079 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 4080 return nanos; 4081 } else { 4082 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 4083 } 4084#else 4085 Unimplemented(); 4086 return 0; 4087#endif 4088} 4089 4090 4091void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4092 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4093 info_ptr->may_skip_backward = false; // elapsed time not wall time 4094 info_ptr->may_skip_forward = false; // elapsed time not wall time 4095 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4096} 4097 4098void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 4099 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 4100 info_ptr->may_skip_backward = false; // elapsed time not wall time 4101 info_ptr->may_skip_forward = false; // elapsed time not wall time 4102 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 4103} 4104 4105bool os::is_thread_cpu_time_supported() { 4106#ifdef __APPLE__ 4107 return true; 4108#else 4109 return false; 4110#endif 4111} 4112 4113// System loadavg support. Returns -1 if load average cannot be obtained. 4114// Bsd doesn't yet have a (official) notion of processor sets, 4115// so just return the system wide load average. 4116int os::loadavg(double loadavg[], int nelem) { 4117 return ::getloadavg(loadavg, nelem); 4118} 4119 4120void os::pause() { 4121 char filename[MAX_PATH]; 4122 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 4123 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 4124 } else { 4125 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 4126 } 4127 4128 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 4129 if (fd != -1) { 4130 struct stat buf; 4131 ::close(fd); 4132 while (::stat(filename, &buf) == 0) { 4133 (void)::poll(NULL, 0, 100); 4134 } 4135 } else { 4136 jio_fprintf(stderr, 4137 "Could not open pause file '%s', continuing immediately.\n", filename); 4138 } 4139} 4140 4141 4142// Refer to the comments in os_solaris.cpp park-unpark. 4143// 4144// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 4145// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 4146// For specifics regarding the bug see GLIBC BUGID 261237 : 4147// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 4148// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 4149// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 4150// is used. (The simple C test-case provided in the GLIBC bug report manifests the 4151// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 4152// and monitorenter when we're using 1-0 locking. All those operations may result in 4153// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 4154// of libpthread avoids the problem, but isn't practical. 4155// 4156// Possible remedies: 4157// 4158// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 4159// This is palliative and probabilistic, however. If the thread is preempted 4160// between the call to compute_abstime() and pthread_cond_timedwait(), more 4161// than the minimum period may have passed, and the abstime may be stale (in the 4162// past) resultin in a hang. Using this technique reduces the odds of a hang 4163// but the JVM is still vulnerable, particularly on heavily loaded systems. 4164// 4165// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 4166// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 4167// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 4168// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 4169// thread. 4170// 4171// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 4172// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 4173// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 4174// This also works well. In fact it avoids kernel-level scalability impediments 4175// on certain platforms that don't handle lots of active pthread_cond_timedwait() 4176// timers in a graceful fashion. 4177// 4178// 4. When the abstime value is in the past it appears that control returns 4179// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 4180// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 4181// can avoid the problem by reinitializing the condvar -- by cond_destroy() 4182// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 4183// It may be possible to avoid reinitialization by checking the return 4184// value from pthread_cond_timedwait(). In addition to reinitializing the 4185// condvar we must establish the invariant that cond_signal() is only called 4186// within critical sections protected by the adjunct mutex. This prevents 4187// cond_signal() from "seeing" a condvar that's in the midst of being 4188// reinitialized or that is corrupt. Sadly, this invariant obviates the 4189// desirable signal-after-unlock optimization that avoids futile context switching. 4190// 4191// I'm also concerned that some versions of NTPL might allocate an auxilliary 4192// structure when a condvar is used or initialized. cond_destroy() would 4193// release the helper structure. Our reinitialize-after-timedwait fix 4194// put excessive stress on malloc/free and locks protecting the c-heap. 4195// 4196// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 4197// It may be possible to refine (4) by checking the kernel and NTPL verisons 4198// and only enabling the work-around for vulnerable environments. 4199 4200// utility to compute the abstime argument to timedwait: 4201// millis is the relative timeout time 4202// abstime will be the absolute timeout time 4203// TODO: replace compute_abstime() with unpackTime() 4204 4205static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 4206 if (millis < 0) millis = 0; 4207 struct timeval now; 4208 int status = gettimeofday(&now, NULL); 4209 assert(status == 0, "gettimeofday"); 4210 jlong seconds = millis / 1000; 4211 millis %= 1000; 4212 if (seconds > 50000000) { // see man cond_timedwait(3T) 4213 seconds = 50000000; 4214 } 4215 abstime->tv_sec = now.tv_sec + seconds; 4216 long usec = now.tv_usec + millis * 1000; 4217 if (usec >= 1000000) { 4218 abstime->tv_sec += 1; 4219 usec -= 1000000; 4220 } 4221 abstime->tv_nsec = usec * 1000; 4222 return abstime; 4223} 4224 4225void os::PlatformEvent::park() { // AKA "down()" 4226 // Invariant: Only the thread associated with the Event/PlatformEvent 4227 // may call park(). 4228 // TODO: assert that _Assoc != NULL or _Assoc == Self 4229 assert(_nParked == 0, "invariant"); 4230 4231 int v; 4232 for (;;) { 4233 v = _Event; 4234 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4235 } 4236 guarantee(v >= 0, "invariant"); 4237 if (v == 0) { 4238 // Do this the hard way by blocking ... 4239 int status = pthread_mutex_lock(_mutex); 4240 assert_status(status == 0, status, "mutex_lock"); 4241 guarantee(_nParked == 0, "invariant"); 4242 ++_nParked; 4243 while (_Event < 0) { 4244 status = pthread_cond_wait(_cond, _mutex); 4245 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 4246 // Treat this the same as if the wait was interrupted 4247 if (status == ETIMEDOUT) { status = EINTR; } 4248 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 4249 } 4250 --_nParked; 4251 4252 _Event = 0; 4253 status = pthread_mutex_unlock(_mutex); 4254 assert_status(status == 0, status, "mutex_unlock"); 4255 // Paranoia to ensure our locked and lock-free paths interact 4256 // correctly with each other. 4257 OrderAccess::fence(); 4258 } 4259 guarantee(_Event >= 0, "invariant"); 4260} 4261 4262int os::PlatformEvent::park(jlong millis) { 4263 guarantee(_nParked == 0, "invariant"); 4264 4265 int v; 4266 for (;;) { 4267 v = _Event; 4268 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; 4269 } 4270 guarantee(v >= 0, "invariant"); 4271 if (v != 0) return OS_OK; 4272 4273 // We do this the hard way, by blocking the thread. 4274 // Consider enforcing a minimum timeout value. 4275 struct timespec abst; 4276 compute_abstime(&abst, millis); 4277 4278 int ret = OS_TIMEOUT; 4279 int status = pthread_mutex_lock(_mutex); 4280 assert_status(status == 0, status, "mutex_lock"); 4281 guarantee(_nParked == 0, "invariant"); 4282 ++_nParked; 4283 4284 // Object.wait(timo) will return because of 4285 // (a) notification 4286 // (b) timeout 4287 // (c) thread.interrupt 4288 // 4289 // Thread.interrupt and object.notify{All} both call Event::set. 4290 // That is, we treat thread.interrupt as a special case of notification. 4291 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. 4292 // We assume all ETIME returns are valid. 4293 // 4294 // TODO: properly differentiate simultaneous notify+interrupt. 4295 // In that case, we should propagate the notify to another waiter. 4296 4297 while (_Event < 0) { 4298 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 4299 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4300 pthread_cond_destroy(_cond); 4301 pthread_cond_init(_cond, NULL); 4302 } 4303 assert_status(status == 0 || status == EINTR || 4304 status == ETIMEDOUT, 4305 status, "cond_timedwait"); 4306 if (!FilterSpuriousWakeups) break; // previous semantics 4307 if (status == ETIMEDOUT) break; 4308 // We consume and ignore EINTR and spurious wakeups. 4309 } 4310 --_nParked; 4311 if (_Event >= 0) { 4312 ret = OS_OK; 4313 } 4314 _Event = 0; 4315 status = pthread_mutex_unlock(_mutex); 4316 assert_status(status == 0, status, "mutex_unlock"); 4317 assert(_nParked == 0, "invariant"); 4318 // Paranoia to ensure our locked and lock-free paths interact 4319 // correctly with each other. 4320 OrderAccess::fence(); 4321 return ret; 4322} 4323 4324void os::PlatformEvent::unpark() { 4325 // Transitions for _Event: 4326 // 0 :=> 1 4327 // 1 :=> 1 4328 // -1 :=> either 0 or 1; must signal target thread 4329 // That is, we can safely transition _Event from -1 to either 4330 // 0 or 1. 4331 // See also: "Semaphores in Plan 9" by Mullender & Cox 4332 // 4333 // Note: Forcing a transition from "-1" to "1" on an unpark() means 4334 // that it will take two back-to-back park() calls for the owning 4335 // thread to block. This has the benefit of forcing a spurious return 4336 // from the first park() call after an unpark() call which will help 4337 // shake out uses of park() and unpark() without condition variables. 4338 4339 if (Atomic::xchg(1, &_Event) >= 0) return; 4340 4341 // Wait for the thread associated with the event to vacate 4342 int status = pthread_mutex_lock(_mutex); 4343 assert_status(status == 0, status, "mutex_lock"); 4344 int AnyWaiters = _nParked; 4345 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); 4346 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 4347 AnyWaiters = 0; 4348 pthread_cond_signal(_cond); 4349 } 4350 status = pthread_mutex_unlock(_mutex); 4351 assert_status(status == 0, status, "mutex_unlock"); 4352 if (AnyWaiters != 0) { 4353 status = pthread_cond_signal(_cond); 4354 assert_status(status == 0, status, "cond_signal"); 4355 } 4356 4357 // Note that we signal() _after dropping the lock for "immortal" Events. 4358 // This is safe and avoids a common class of futile wakeups. In rare 4359 // circumstances this can cause a thread to return prematurely from 4360 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 4361 // simply re-test the condition and re-park itself. 4362} 4363 4364 4365// JSR166 4366// ------------------------------------------------------- 4367 4368/* 4369 * The solaris and bsd implementations of park/unpark are fairly 4370 * conservative for now, but can be improved. They currently use a 4371 * mutex/condvar pair, plus a a count. 4372 * Park decrements count if > 0, else does a condvar wait. Unpark 4373 * sets count to 1 and signals condvar. Only one thread ever waits 4374 * on the condvar. Contention seen when trying to park implies that someone 4375 * is unparking you, so don't wait. And spurious returns are fine, so there 4376 * is no need to track notifications. 4377 */ 4378 4379#define MAX_SECS 100000000 4380/* 4381 * This code is common to bsd and solaris and will be moved to a 4382 * common place in dolphin. 4383 * 4384 * The passed in time value is either a relative time in nanoseconds 4385 * or an absolute time in milliseconds. Either way it has to be unpacked 4386 * into suitable seconds and nanoseconds components and stored in the 4387 * given timespec structure. 4388 * Given time is a 64-bit value and the time_t used in the timespec is only 4389 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 4390 * overflow if times way in the future are given. Further on Solaris versions 4391 * prior to 10 there is a restriction (see cond_timedwait) that the specified 4392 * number of seconds, in abstime, is less than current_time + 100,000,000. 4393 * As it will be 28 years before "now + 100000000" will overflow we can 4394 * ignore overflow and just impose a hard-limit on seconds using the value 4395 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 4396 * years from "now". 4397 */ 4398 4399static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 4400 assert(time > 0, "convertTime"); 4401 4402 struct timeval now; 4403 int status = gettimeofday(&now, NULL); 4404 assert(status == 0, "gettimeofday"); 4405 4406 time_t max_secs = now.tv_sec + MAX_SECS; 4407 4408 if (isAbsolute) { 4409 jlong secs = time / 1000; 4410 if (secs > max_secs) { 4411 absTime->tv_sec = max_secs; 4412 } 4413 else { 4414 absTime->tv_sec = secs; 4415 } 4416 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 4417 } 4418 else { 4419 jlong secs = time / NANOSECS_PER_SEC; 4420 if (secs >= MAX_SECS) { 4421 absTime->tv_sec = max_secs; 4422 absTime->tv_nsec = 0; 4423 } 4424 else { 4425 absTime->tv_sec = now.tv_sec + secs; 4426 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 4427 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 4428 absTime->tv_nsec -= NANOSECS_PER_SEC; 4429 ++absTime->tv_sec; // note: this must be <= max_secs 4430 } 4431 } 4432 } 4433 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 4434 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 4435 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 4436 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 4437} 4438 4439void Parker::park(bool isAbsolute, jlong time) { 4440 // Ideally we'd do something useful while spinning, such 4441 // as calling unpackTime(). 4442 4443 // Optional fast-path check: 4444 // Return immediately if a permit is available. 4445 // We depend on Atomic::xchg() having full barrier semantics 4446 // since we are doing a lock-free update to _counter. 4447 if (Atomic::xchg(0, &_counter) > 0) return; 4448 4449 Thread* thread = Thread::current(); 4450 assert(thread->is_Java_thread(), "Must be JavaThread"); 4451 JavaThread *jt = (JavaThread *)thread; 4452 4453 // Optional optimization -- avoid state transitions if there's an interrupt pending. 4454 // Check interrupt before trying to wait 4455 if (Thread::is_interrupted(thread, false)) { 4456 return; 4457 } 4458 4459 // Next, demultiplex/decode time arguments 4460 struct timespec absTime; 4461 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all 4462 return; 4463 } 4464 if (time > 0) { 4465 unpackTime(&absTime, isAbsolute, time); 4466 } 4467 4468 4469 // Enter safepoint region 4470 // Beware of deadlocks such as 6317397. 4471 // The per-thread Parker:: mutex is a classic leaf-lock. 4472 // In particular a thread must never block on the Threads_lock while 4473 // holding the Parker:: mutex. If safepoints are pending both the 4474 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 4475 ThreadBlockInVM tbivm(jt); 4476 4477 // Don't wait if cannot get lock since interference arises from 4478 // unblocking. Also. check interrupt before trying wait 4479 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 4480 return; 4481 } 4482 4483 int status; 4484 if (_counter > 0) { // no wait needed 4485 _counter = 0; 4486 status = pthread_mutex_unlock(_mutex); 4487 assert(status == 0, "invariant"); 4488 // Paranoia to ensure our locked and lock-free paths interact 4489 // correctly with each other and Java-level accesses. 4490 OrderAccess::fence(); 4491 return; 4492 } 4493 4494#ifdef ASSERT 4495 // Don't catch signals while blocked; let the running threads have the signals. 4496 // (This allows a debugger to break into the running thread.) 4497 sigset_t oldsigs; 4498 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 4499 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 4500#endif 4501 4502 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 4503 jt->set_suspend_equivalent(); 4504 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 4505 4506 if (time == 0) { 4507 status = pthread_cond_wait(_cond, _mutex); 4508 } else { 4509 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &absTime); 4510 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 4511 pthread_cond_destroy(_cond); 4512 pthread_cond_init(_cond, NULL); 4513 } 4514 } 4515 assert_status(status == 0 || status == EINTR || 4516 status == ETIMEDOUT, 4517 status, "cond_timedwait"); 4518 4519#ifdef ASSERT 4520 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 4521#endif 4522 4523 _counter = 0; 4524 status = pthread_mutex_unlock(_mutex); 4525 assert_status(status == 0, status, "invariant"); 4526 // Paranoia to ensure our locked and lock-free paths interact 4527 // correctly with each other and Java-level accesses. 4528 OrderAccess::fence(); 4529 4530 // If externally suspended while waiting, re-suspend 4531 if (jt->handle_special_suspend_equivalent_condition()) { 4532 jt->java_suspend_self(); 4533 } 4534} 4535 4536void Parker::unpark() { 4537 int status = pthread_mutex_lock(_mutex); 4538 assert(status == 0, "invariant"); 4539 const int s = _counter; 4540 _counter = 1; 4541 if (s < 1) { 4542 if (WorkAroundNPTLTimedWaitHang) { 4543 status = pthread_cond_signal(_cond); 4544 assert(status == 0, "invariant"); 4545 status = pthread_mutex_unlock(_mutex); 4546 assert(status == 0, "invariant"); 4547 } else { 4548 status = pthread_mutex_unlock(_mutex); 4549 assert(status == 0, "invariant"); 4550 status = pthread_cond_signal(_cond); 4551 assert(status == 0, "invariant"); 4552 } 4553 } else { 4554 pthread_mutex_unlock(_mutex); 4555 assert(status == 0, "invariant"); 4556 } 4557} 4558 4559 4560/* Darwin has no "environ" in a dynamic library. */ 4561#ifdef __APPLE__ 4562#include <crt_externs.h> 4563#define environ (*_NSGetEnviron()) 4564#else 4565extern char** environ; 4566#endif 4567 4568// Run the specified command in a separate process. Return its exit value, 4569// or -1 on failure (e.g. can't fork a new process). 4570// Unlike system(), this function can be called from signal handler. It 4571// doesn't block SIGINT et al. 4572int os::fork_and_exec(char* cmd) { 4573 const char * argv[4] = {"sh", "-c", cmd, NULL}; 4574 4575 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 4576 // pthread_atfork handlers and reset pthread library. All we need is a 4577 // separate process to execve. Make a direct syscall to fork process. 4578 // On IA64 there's no fork syscall, we have to use fork() and hope for 4579 // the best... 4580 pid_t pid = fork(); 4581 4582 if (pid < 0) { 4583 // fork failed 4584 return -1; 4585 4586 } else if (pid == 0) { 4587 // child process 4588 4589 // execve() in BsdThreads will call pthread_kill_other_threads_np() 4590 // first to kill every thread on the thread list. Because this list is 4591 // not reset by fork() (see notes above), execve() will instead kill 4592 // every thread in the parent process. We know this is the only thread 4593 // in the new process, so make a system call directly. 4594 // IA64 should use normal execve() from glibc to match the glibc fork() 4595 // above. 4596 execve("/bin/sh", (char* const*)argv, environ); 4597 4598 // execve failed 4599 _exit(-1); 4600 4601 } else { 4602 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 4603 // care about the actual exit code, for now. 4604 4605 int status; 4606 4607 // Wait for the child process to exit. This returns immediately if 4608 // the child has already exited. */ 4609 while (waitpid(pid, &status, 0) < 0) { 4610 switch (errno) { 4611 case ECHILD: return 0; 4612 case EINTR: break; 4613 default: return -1; 4614 } 4615 } 4616 4617 if (WIFEXITED(status)) { 4618 // The child exited normally; get its exit code. 4619 return WEXITSTATUS(status); 4620 } else if (WIFSIGNALED(status)) { 4621 // The child exited because of a signal 4622 // The best value to return is 0x80 + signal number, 4623 // because that is what all Unix shells do, and because 4624 // it allows callers to distinguish between process exit and 4625 // process death by signal. 4626 return 0x80 + WTERMSIG(status); 4627 } else { 4628 // Unknown exit code; pass it through 4629 return status; 4630 } 4631 } 4632} 4633 4634// is_headless_jre() 4635// 4636// Test for the existence of xawt/libmawt.so or libawt_xawt.so 4637// in order to report if we are running in a headless jre 4638// 4639// Since JDK8 xawt/libmawt.so was moved into the same directory 4640// as libawt.so, and renamed libawt_xawt.so 4641// 4642bool os::is_headless_jre() { 4643#ifdef __APPLE__ 4644 // We no longer build headless-only on Mac OS X 4645 return false; 4646#else 4647 struct stat statbuf; 4648 char buf[MAXPATHLEN]; 4649 char libmawtpath[MAXPATHLEN]; 4650 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 4651 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 4652 char *p; 4653 4654 // Get path to libjvm.so 4655 os::jvm_path(buf, sizeof(buf)); 4656 4657 // Get rid of libjvm.so 4658 p = strrchr(buf, '/'); 4659 if (p == NULL) return false; 4660 else *p = '\0'; 4661 4662 // Get rid of client or server 4663 p = strrchr(buf, '/'); 4664 if (p == NULL) return false; 4665 else *p = '\0'; 4666 4667 // check xawt/libmawt.so 4668 strcpy(libmawtpath, buf); 4669 strcat(libmawtpath, xawtstr); 4670 if (::stat(libmawtpath, &statbuf) == 0) return false; 4671 4672 // check libawt_xawt.so 4673 strcpy(libmawtpath, buf); 4674 strcat(libmawtpath, new_xawtstr); 4675 if (::stat(libmawtpath, &statbuf) == 0) return false; 4676 4677 return true; 4678#endif 4679} 4680 4681// Get the default path to the core file 4682// Returns the length of the string 4683int os::get_core_path(char* buffer, size_t bufferSize) { 4684 int n = jio_snprintf(buffer, bufferSize, "/cores"); 4685 4686 // Truncate if theoretical string was longer than bufferSize 4687 n = MIN2(n, (int)bufferSize); 4688 4689 return n; 4690} 4691 4692#ifndef PRODUCT 4693void TestReserveMemorySpecial_test() { 4694 // No tests available for this platform 4695} 4696#endif 4697