os_bsd.cpp revision 3038:e8a4934564b2
1/* 2 * Copyright (c) 1999, 2011, 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 "interpreter/interpreter.hpp" 33#include "jvm_bsd.h" 34#include "memory/allocation.inline.hpp" 35#include "memory/filemap.hpp" 36#include "mutex_bsd.inline.hpp" 37#include "oops/oop.inline.hpp" 38#include "os_share_bsd.hpp" 39#include "prims/jniFastGetField.hpp" 40#include "prims/jvm.h" 41#include "prims/jvm_misc.hpp" 42#include "runtime/arguments.hpp" 43#include "runtime/extendedPC.hpp" 44#include "runtime/globals.hpp" 45#include "runtime/interfaceSupport.hpp" 46#include "runtime/java.hpp" 47#include "runtime/javaCalls.hpp" 48#include "runtime/mutexLocker.hpp" 49#include "runtime/objectMonitor.hpp" 50#include "runtime/osThread.hpp" 51#include "runtime/perfMemory.hpp" 52#include "runtime/sharedRuntime.hpp" 53#include "runtime/statSampler.hpp" 54#include "runtime/stubRoutines.hpp" 55#include "runtime/threadCritical.hpp" 56#include "runtime/timer.hpp" 57#include "services/attachListener.hpp" 58#include "services/runtimeService.hpp" 59#include "thread_bsd.inline.hpp" 60#include "utilities/decoder.hpp" 61#include "utilities/defaultStream.hpp" 62#include "utilities/events.hpp" 63#include "utilities/growableArray.hpp" 64#include "utilities/vmError.hpp" 65#ifdef TARGET_ARCH_x86 66# include "assembler_x86.inline.hpp" 67# include "nativeInst_x86.hpp" 68#endif 69#ifdef TARGET_ARCH_sparc 70# include "assembler_sparc.inline.hpp" 71# include "nativeInst_sparc.hpp" 72#endif 73#ifdef TARGET_ARCH_zero 74# include "assembler_zero.inline.hpp" 75# include "nativeInst_zero.hpp" 76#endif 77#ifdef TARGET_ARCH_arm 78# include "assembler_arm.inline.hpp" 79# include "nativeInst_arm.hpp" 80#endif 81#ifdef TARGET_ARCH_ppc 82# include "assembler_ppc.inline.hpp" 83# include "nativeInst_ppc.hpp" 84#endif 85#ifdef COMPILER1 86#include "c1/c1_Runtime1.hpp" 87#endif 88#ifdef COMPILER2 89#include "opto/runtime.hpp" 90#endif 91 92// put OS-includes here 93# include <sys/types.h> 94# include <sys/mman.h> 95# include <sys/stat.h> 96# include <sys/select.h> 97# include <pthread.h> 98# include <signal.h> 99# include <errno.h> 100# include <dlfcn.h> 101# include <stdio.h> 102# include <unistd.h> 103# include <sys/resource.h> 104# include <pthread.h> 105# include <sys/stat.h> 106# include <sys/time.h> 107# include <sys/times.h> 108# include <sys/utsname.h> 109# include <sys/socket.h> 110# include <sys/wait.h> 111# include <time.h> 112# include <pwd.h> 113# include <poll.h> 114# include <semaphore.h> 115# include <fcntl.h> 116# include <string.h> 117#ifdef _ALLBSD_SOURCE 118# include <sys/param.h> 119# include <sys/sysctl.h> 120#else 121# include <syscall.h> 122# include <sys/sysinfo.h> 123# include <gnu/libc-version.h> 124#endif 125# include <sys/ipc.h> 126# include <sys/shm.h> 127#ifndef __APPLE__ 128# include <link.h> 129#endif 130# include <stdint.h> 131# include <inttypes.h> 132# include <sys/ioctl.h> 133 134#if defined(__FreeBSD__) || defined(__NetBSD__) 135# include <elf.h> 136#endif 137 138#ifdef __APPLE__ 139# include <mach/mach.h> // semaphore_* API 140# include <mach-o/dyld.h> 141# include <sys/proc_info.h> 142# include <objc/objc-auto.h> 143#endif 144 145#ifndef MAP_ANONYMOUS 146#define MAP_ANONYMOUS MAP_ANON 147#endif 148 149#define MAX_PATH (2 * K) 150 151// for timer info max values which include all bits 152#define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) 153 154#define LARGEPAGES_BIT (1 << 6) 155//////////////////////////////////////////////////////////////////////////////// 156// global variables 157julong os::Bsd::_physical_memory = 0; 158 159#ifndef _ALLBSD_SOURCE 160address os::Bsd::_initial_thread_stack_bottom = NULL; 161uintptr_t os::Bsd::_initial_thread_stack_size = 0; 162#endif 163 164int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; 165#ifndef _ALLBSD_SOURCE 166int (*os::Bsd::_pthread_getcpuclockid)(pthread_t, clockid_t *) = NULL; 167Mutex* os::Bsd::_createThread_lock = NULL; 168#endif 169pthread_t os::Bsd::_main_thread; 170int os::Bsd::_page_size = -1; 171#ifndef _ALLBSD_SOURCE 172bool os::Bsd::_is_floating_stack = false; 173bool os::Bsd::_is_NPTL = false; 174bool os::Bsd::_supports_fast_thread_cpu_time = false; 175const char * os::Bsd::_glibc_version = NULL; 176const char * os::Bsd::_libpthread_version = NULL; 177#endif 178 179static jlong initial_time_count=0; 180 181static int clock_tics_per_sec = 100; 182 183// For diagnostics to print a message once. see run_periodic_checks 184static sigset_t check_signal_done; 185static bool check_signals = true;; 186 187static pid_t _initial_pid = 0; 188 189/* Signal number used to suspend/resume a thread */ 190 191/* do not use any signal number less than SIGSEGV, see 4355769 */ 192static int SR_signum = SIGUSR2; 193sigset_t SR_sigset; 194 195 196//////////////////////////////////////////////////////////////////////////////// 197// utility functions 198 199static int SR_initialize(); 200static int SR_finalize(); 201 202julong os::available_memory() { 203 return Bsd::available_memory(); 204} 205 206julong os::Bsd::available_memory() { 207#ifdef _ALLBSD_SOURCE 208 // XXXBSD: this is just a stopgap implementation 209 return physical_memory() >> 2; 210#else 211 // values in struct sysinfo are "unsigned long" 212 struct sysinfo si; 213 sysinfo(&si); 214 215 return (julong)si.freeram * si.mem_unit; 216#endif 217} 218 219julong os::physical_memory() { 220 return Bsd::physical_memory(); 221} 222 223julong os::allocatable_physical_memory(julong size) { 224#ifdef _LP64 225 return size; 226#else 227 julong result = MIN2(size, (julong)3800*M); 228 if (!is_allocatable(result)) { 229 // See comments under solaris for alignment considerations 230 julong reasonable_size = (julong)2*G - 2 * os::vm_page_size(); 231 result = MIN2(size, reasonable_size); 232 } 233 return result; 234#endif // _LP64 235} 236 237//////////////////////////////////////////////////////////////////////////////// 238// environment support 239 240bool os::getenv(const char* name, char* buf, int len) { 241 const char* val = ::getenv(name); 242 if (val != NULL && strlen(val) < (size_t)len) { 243 strcpy(buf, val); 244 return true; 245 } 246 if (len > 0) buf[0] = 0; // return a null string 247 return false; 248} 249 250 251// Return true if user is running as root. 252 253bool os::have_special_privileges() { 254 static bool init = false; 255 static bool privileges = false; 256 if (!init) { 257 privileges = (getuid() != geteuid()) || (getgid() != getegid()); 258 init = true; 259 } 260 return privileges; 261} 262 263 264#ifndef _ALLBSD_SOURCE 265#ifndef SYS_gettid 266// i386: 224, ia64: 1105, amd64: 186, sparc 143 267#ifdef __ia64__ 268#define SYS_gettid 1105 269#elif __i386__ 270#define SYS_gettid 224 271#elif __amd64__ 272#define SYS_gettid 186 273#elif __sparc__ 274#define SYS_gettid 143 275#else 276#error define gettid for the arch 277#endif 278#endif 279#endif 280 281// Cpu architecture string 282#if defined(ZERO) 283static char cpu_arch[] = ZERO_LIBARCH; 284#elif defined(IA64) 285static char cpu_arch[] = "ia64"; 286#elif defined(IA32) 287static char cpu_arch[] = "i386"; 288#elif defined(AMD64) 289static char cpu_arch[] = "amd64"; 290#elif defined(ARM) 291static char cpu_arch[] = "arm"; 292#elif defined(PPC) 293static char cpu_arch[] = "ppc"; 294#elif defined(SPARC) 295# ifdef _LP64 296static char cpu_arch[] = "sparcv9"; 297# else 298static char cpu_arch[] = "sparc"; 299# endif 300#else 301#error Add appropriate cpu_arch setting 302#endif 303 304// Compiler variant 305#ifdef COMPILER2 306#define COMPILER_VARIANT "server" 307#else 308#define COMPILER_VARIANT "client" 309#endif 310 311#ifndef _ALLBSD_SOURCE 312// pid_t gettid() 313// 314// Returns the kernel thread id of the currently running thread. Kernel 315// thread id is used to access /proc. 316// 317// (Note that getpid() on BsdThreads returns kernel thread id too; but 318// on NPTL, it returns the same pid for all threads, as required by POSIX.) 319// 320pid_t os::Bsd::gettid() { 321 int rslt = syscall(SYS_gettid); 322 if (rslt == -1) { 323 // old kernel, no NPTL support 324 return getpid(); 325 } else { 326 return (pid_t)rslt; 327 } 328} 329 330// Most versions of bsd have a bug where the number of processors are 331// determined by looking at the /proc file system. In a chroot environment, 332// the system call returns 1. This causes the VM to act as if it is 333// a single processor and elide locking (see is_MP() call). 334static bool unsafe_chroot_detected = false; 335static const char *unstable_chroot_error = "/proc file system not found.\n" 336 "Java may be unstable running multithreaded in a chroot " 337 "environment on Bsd when /proc filesystem is not mounted."; 338#endif 339 340#ifdef _ALLBSD_SOURCE 341void os::Bsd::initialize_system_info() { 342 int mib[2]; 343 size_t len; 344 int cpu_val; 345 u_long mem_val; 346 347 /* get processors count via hw.ncpus sysctl */ 348 mib[0] = CTL_HW; 349 mib[1] = HW_NCPU; 350 len = sizeof(cpu_val); 351 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { 352 set_processor_count(cpu_val); 353 } 354 else { 355 set_processor_count(1); // fallback 356 } 357 358 /* get physical memory via hw.usermem sysctl (hw.usermem is used 359 * instead of hw.physmem because we need size of allocatable memory 360 */ 361 mib[0] = CTL_HW; 362 mib[1] = HW_USERMEM; 363 len = sizeof(mem_val); 364 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) 365 _physical_memory = mem_val; 366 else 367 _physical_memory = 256*1024*1024; // fallback (XXXBSD?) 368 369#ifdef __OpenBSD__ 370 { 371 // limit _physical_memory memory view on OpenBSD since 372 // datasize rlimit restricts us anyway. 373 struct rlimit limits; 374 getrlimit(RLIMIT_DATA, &limits); 375 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); 376 } 377#endif 378} 379#else 380void os::Bsd::initialize_system_info() { 381 set_processor_count(sysconf(_SC_NPROCESSORS_CONF)); 382 if (processor_count() == 1) { 383 pid_t pid = os::Bsd::gettid(); 384 char fname[32]; 385 jio_snprintf(fname, sizeof(fname), "/proc/%d", pid); 386 FILE *fp = fopen(fname, "r"); 387 if (fp == NULL) { 388 unsafe_chroot_detected = true; 389 } else { 390 fclose(fp); 391 } 392 } 393 _physical_memory = (julong)sysconf(_SC_PHYS_PAGES) * (julong)sysconf(_SC_PAGESIZE); 394 assert(processor_count() > 0, "bsd error"); 395} 396#endif 397 398#ifdef __APPLE__ 399static const char *get_home() { 400 const char *home_dir = ::getenv("HOME"); 401 if ((home_dir == NULL) || (*home_dir == '\0')) { 402 struct passwd *passwd_info = getpwuid(geteuid()); 403 if (passwd_info != NULL) { 404 home_dir = passwd_info->pw_dir; 405 } 406 } 407 408 return home_dir; 409} 410#endif 411 412void os::init_system_properties_values() { 413// char arch[12]; 414// sysinfo(SI_ARCHITECTURE, arch, sizeof(arch)); 415 416 // The next steps are taken in the product version: 417 // 418 // Obtain the JAVA_HOME value from the location of libjvm[_g].so. 419 // This library should be located at: 420 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm[_g].so. 421 // 422 // If "/jre/lib/" appears at the right place in the path, then we 423 // assume libjvm[_g].so is installed in a JDK and we use this path. 424 // 425 // Otherwise exit with message: "Could not create the Java virtual machine." 426 // 427 // The following extra steps are taken in the debugging version: 428 // 429 // If "/jre/lib/" does NOT appear at the right place in the path 430 // instead of exit check for $JAVA_HOME environment variable. 431 // 432 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>, 433 // then we append a fake suffix "hotspot/libjvm[_g].so" to this path so 434 // it looks like libjvm[_g].so is installed there 435 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm[_g].so. 436 // 437 // Otherwise exit. 438 // 439 // Important note: if the location of libjvm.so changes this 440 // code needs to be changed accordingly. 441 442 // The next few definitions allow the code to be verbatim: 443#define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n)) 444#define getenv(n) ::getenv(n) 445 446/* 447 * See ld(1): 448 * The linker uses the following search paths to locate required 449 * shared libraries: 450 * 1: ... 451 * ... 452 * 7: The default directories, normally /lib and /usr/lib. 453 */ 454#ifndef DEFAULT_LIBPATH 455#define DEFAULT_LIBPATH "/lib:/usr/lib" 456#endif 457 458#define EXTENSIONS_DIR "/lib/ext" 459#define ENDORSED_DIR "/lib/endorsed" 460#define REG_DIR "/usr/java/packages" 461 462#ifdef __APPLE__ 463#define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" 464#define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" 465 const char *user_home_dir = get_home(); 466 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir 467 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + 468 sizeof(SYS_EXTENSIONS_DIRS); 469#endif 470 471 { 472 /* sysclasspath, java_home, dll_dir */ 473 { 474 char *home_path; 475 char *dll_path; 476 char *pslash; 477 char buf[MAXPATHLEN]; 478 os::jvm_path(buf, sizeof(buf)); 479 480 // Found the full path to libjvm.so. 481 // Now cut the path to <java_home>/jre if we can. 482 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */ 483 pslash = strrchr(buf, '/'); 484 if (pslash != NULL) 485 *pslash = '\0'; /* get rid of /{client|server|hotspot} */ 486 dll_path = malloc(strlen(buf) + 1); 487 if (dll_path == NULL) 488 return; 489 strcpy(dll_path, buf); 490 Arguments::set_dll_dir(dll_path); 491 492 if (pslash != NULL) { 493 pslash = strrchr(buf, '/'); 494 if (pslash != NULL) { 495 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */ 496#ifndef __APPLE__ 497 pslash = strrchr(buf, '/'); 498 if (pslash != NULL) 499 *pslash = '\0'; /* get rid of /lib */ 500#endif 501 } 502 } 503 504 home_path = malloc(strlen(buf) + 1); 505 if (home_path == NULL) 506 return; 507 strcpy(home_path, buf); 508 Arguments::set_java_home(home_path); 509 510 if (!set_boot_path('/', ':')) 511 return; 512 } 513 514 /* 515 * Where to look for native libraries 516 * 517 * Note: Due to a legacy implementation, most of the library path 518 * is set in the launcher. This was to accomodate linking restrictions 519 * on legacy Bsd implementations (which are no longer supported). 520 * Eventually, all the library path setting will be done here. 521 * 522 * However, to prevent the proliferation of improperly built native 523 * libraries, the new path component /usr/java/packages is added here. 524 * Eventually, all the library path setting will be done here. 525 */ 526 { 527 char *ld_library_path; 528 529 /* 530 * Construct the invariant part of ld_library_path. Note that the 531 * space for the colon and the trailing null are provided by the 532 * nulls included by the sizeof operator (so actually we allocate 533 * a byte more than necessary). 534 */ 535#ifdef __APPLE__ 536 ld_library_path = (char *) malloc(system_ext_size); 537 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir); 538#else 539 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") + 540 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH)); 541 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch); 542#endif 543 544 /* 545 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It 546 * should always exist (until the legacy problem cited above is 547 * addressed). 548 */ 549#ifdef __APPLE__ 550 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper 551 char *l = getenv("JAVA_LIBRARY_PATH"); 552 if (l != NULL) { 553 char *t = ld_library_path; 554 /* That's +1 for the colon and +1 for the trailing '\0' */ 555 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1); 556 sprintf(ld_library_path, "%s:%s", l, t); 557 free(t); 558 } 559 560 char *v = getenv("DYLD_LIBRARY_PATH"); 561#else 562 char *v = getenv("LD_LIBRARY_PATH"); 563#endif 564 if (v != NULL) { 565 char *t = ld_library_path; 566 /* That's +1 for the colon and +1 for the trailing '\0' */ 567 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1); 568 sprintf(ld_library_path, "%s:%s", v, t); 569 free(t); 570 } 571 Arguments::set_library_path(ld_library_path); 572 } 573 574 /* 575 * Extensions directories. 576 * 577 * Note that the space for the colon and the trailing null are provided 578 * by the nulls included by the sizeof operator (so actually one byte more 579 * than necessary is allocated). 580 */ 581 { 582#ifdef __APPLE__ 583 char *buf = malloc(strlen(Arguments::get_java_home()) + 584 sizeof(EXTENSIONS_DIR) + system_ext_size); 585 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" 586 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home()); 587#else 588 char *buf = malloc(strlen(Arguments::get_java_home()) + 589 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR)); 590 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR, 591 Arguments::get_java_home()); 592#endif 593 594 Arguments::set_ext_dirs(buf); 595 } 596 597 /* Endorsed standards default directory. */ 598 { 599 char * buf; 600 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR)); 601 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 602 Arguments::set_endorsed_dirs(buf); 603 } 604 } 605 606#ifdef __APPLE__ 607#undef SYS_EXTENSIONS_DIR 608#endif 609#undef malloc 610#undef getenv 611#undef EXTENSIONS_DIR 612#undef ENDORSED_DIR 613 614 // Done 615 return; 616} 617 618//////////////////////////////////////////////////////////////////////////////// 619// breakpoint support 620 621void os::breakpoint() { 622 BREAKPOINT; 623} 624 625extern "C" void breakpoint() { 626 // use debugger to set breakpoint here 627} 628 629//////////////////////////////////////////////////////////////////////////////// 630// signal support 631 632debug_only(static bool signal_sets_initialized = false); 633static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 634 635bool os::Bsd::is_sig_ignored(int sig) { 636 struct sigaction oact; 637 sigaction(sig, (struct sigaction*)NULL, &oact); 638 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 639 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 640 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 641 return true; 642 else 643 return false; 644} 645 646void os::Bsd::signal_sets_init() { 647 // Should also have an assertion stating we are still single-threaded. 648 assert(!signal_sets_initialized, "Already initialized"); 649 // Fill in signals that are necessarily unblocked for all threads in 650 // the VM. Currently, we unblock the following signals: 651 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 652 // by -Xrs (=ReduceSignalUsage)); 653 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 654 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 655 // the dispositions or masks wrt these signals. 656 // Programs embedding the VM that want to use the above signals for their 657 // own purposes must, at this time, use the "-Xrs" option to prevent 658 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 659 // (See bug 4345157, and other related bugs). 660 // In reality, though, unblocking these signals is really a nop, since 661 // these signals are not blocked by default. 662 sigemptyset(&unblocked_sigs); 663 sigemptyset(&allowdebug_blocked_sigs); 664 sigaddset(&unblocked_sigs, SIGILL); 665 sigaddset(&unblocked_sigs, SIGSEGV); 666 sigaddset(&unblocked_sigs, SIGBUS); 667 sigaddset(&unblocked_sigs, SIGFPE); 668 sigaddset(&unblocked_sigs, SR_signum); 669 670 if (!ReduceSignalUsage) { 671 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 672 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 673 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 674 } 675 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 676 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 677 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 678 } 679 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 680 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 681 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 682 } 683 } 684 // Fill in signals that are blocked by all but the VM thread. 685 sigemptyset(&vm_sigs); 686 if (!ReduceSignalUsage) 687 sigaddset(&vm_sigs, BREAK_SIGNAL); 688 debug_only(signal_sets_initialized = true); 689 690} 691 692// These are signals that are unblocked while a thread is running Java. 693// (For some reason, they get blocked by default.) 694sigset_t* os::Bsd::unblocked_signals() { 695 assert(signal_sets_initialized, "Not initialized"); 696 return &unblocked_sigs; 697} 698 699// These are the signals that are blocked while a (non-VM) thread is 700// running Java. Only the VM thread handles these signals. 701sigset_t* os::Bsd::vm_signals() { 702 assert(signal_sets_initialized, "Not initialized"); 703 return &vm_sigs; 704} 705 706// These are signals that are blocked during cond_wait to allow debugger in 707sigset_t* os::Bsd::allowdebug_blocked_signals() { 708 assert(signal_sets_initialized, "Not initialized"); 709 return &allowdebug_blocked_sigs; 710} 711 712void os::Bsd::hotspot_sigmask(Thread* thread) { 713 714 //Save caller's signal mask before setting VM signal mask 715 sigset_t caller_sigmask; 716 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 717 718 OSThread* osthread = thread->osthread(); 719 osthread->set_caller_sigmask(caller_sigmask); 720 721 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 722 723 if (!ReduceSignalUsage) { 724 if (thread->is_VM_thread()) { 725 // Only the VM thread handles BREAK_SIGNAL ... 726 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 727 } else { 728 // ... all other threads block BREAK_SIGNAL 729 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 730 } 731 } 732} 733 734#ifndef _ALLBSD_SOURCE 735////////////////////////////////////////////////////////////////////////////// 736// detecting pthread library 737 738void os::Bsd::libpthread_init() { 739 // Save glibc and pthread version strings. Note that _CS_GNU_LIBC_VERSION 740 // and _CS_GNU_LIBPTHREAD_VERSION are supported in glibc >= 2.3.2. Use a 741 // generic name for earlier versions. 742 // Define macros here so we can build HotSpot on old systems. 743# ifndef _CS_GNU_LIBC_VERSION 744# define _CS_GNU_LIBC_VERSION 2 745# endif 746# ifndef _CS_GNU_LIBPTHREAD_VERSION 747# define _CS_GNU_LIBPTHREAD_VERSION 3 748# endif 749 750 size_t n = confstr(_CS_GNU_LIBC_VERSION, NULL, 0); 751 if (n > 0) { 752 char *str = (char *)malloc(n); 753 confstr(_CS_GNU_LIBC_VERSION, str, n); 754 os::Bsd::set_glibc_version(str); 755 } else { 756 // _CS_GNU_LIBC_VERSION is not supported, try gnu_get_libc_version() 757 static char _gnu_libc_version[32]; 758 jio_snprintf(_gnu_libc_version, sizeof(_gnu_libc_version), 759 "glibc %s %s", gnu_get_libc_version(), gnu_get_libc_release()); 760 os::Bsd::set_glibc_version(_gnu_libc_version); 761 } 762 763 n = confstr(_CS_GNU_LIBPTHREAD_VERSION, NULL, 0); 764 if (n > 0) { 765 char *str = (char *)malloc(n); 766 confstr(_CS_GNU_LIBPTHREAD_VERSION, str, n); 767 // Vanilla RH-9 (glibc 2.3.2) has a bug that confstr() always tells 768 // us "NPTL-0.29" even we are running with BsdThreads. Check if this 769 // is the case. BsdThreads has a hard limit on max number of threads. 770 // So sysconf(_SC_THREAD_THREADS_MAX) will return a positive value. 771 // On the other hand, NPTL does not have such a limit, sysconf() 772 // will return -1 and errno is not changed. Check if it is really NPTL. 773 if (strcmp(os::Bsd::glibc_version(), "glibc 2.3.2") == 0 && 774 strstr(str, "NPTL") && 775 sysconf(_SC_THREAD_THREADS_MAX) > 0) { 776 free(str); 777 os::Bsd::set_libpthread_version("bsdthreads"); 778 } else { 779 os::Bsd::set_libpthread_version(str); 780 } 781 } else { 782 // glibc before 2.3.2 only has BsdThreads. 783 os::Bsd::set_libpthread_version("bsdthreads"); 784 } 785 786 if (strstr(libpthread_version(), "NPTL")) { 787 os::Bsd::set_is_NPTL(); 788 } else { 789 os::Bsd::set_is_BsdThreads(); 790 } 791 792 // BsdThreads have two flavors: floating-stack mode, which allows variable 793 // stack size; and fixed-stack mode. NPTL is always floating-stack. 794 if (os::Bsd::is_NPTL() || os::Bsd::supports_variable_stack_size()) { 795 os::Bsd::set_is_floating_stack(); 796 } 797} 798 799///////////////////////////////////////////////////////////////////////////// 800// thread stack 801 802// Force Bsd kernel to expand current thread stack. If "bottom" is close 803// to the stack guard, caller should block all signals. 804// 805// MAP_GROWSDOWN: 806// A special mmap() flag that is used to implement thread stacks. It tells 807// kernel that the memory region should extend downwards when needed. This 808// allows early versions of BsdThreads to only mmap the first few pages 809// when creating a new thread. Bsd kernel will automatically expand thread 810// stack as needed (on page faults). 811// 812// However, because the memory region of a MAP_GROWSDOWN stack can grow on 813// demand, if a page fault happens outside an already mapped MAP_GROWSDOWN 814// region, it's hard to tell if the fault is due to a legitimate stack 815// access or because of reading/writing non-exist memory (e.g. buffer 816// overrun). As a rule, if the fault happens below current stack pointer, 817// Bsd kernel does not expand stack, instead a SIGSEGV is sent to the 818// application (see Bsd kernel fault.c). 819// 820// This Bsd feature can cause SIGSEGV when VM bangs thread stack for 821// stack overflow detection. 822// 823// Newer version of BsdThreads (since glibc-2.2, or, RH-7.x) and NPTL do 824// not use this flag. However, the stack of initial thread is not created 825// by pthread, it is still MAP_GROWSDOWN. Also it's possible (though 826// unlikely) that user code can create a thread with MAP_GROWSDOWN stack 827// and then attach the thread to JVM. 828// 829// To get around the problem and allow stack banging on Bsd, we need to 830// manually expand thread stack after receiving the SIGSEGV. 831// 832// There are two ways to expand thread stack to address "bottom", we used 833// both of them in JVM before 1.5: 834// 1. adjust stack pointer first so that it is below "bottom", and then 835// touch "bottom" 836// 2. mmap() the page in question 837// 838// Now alternate signal stack is gone, it's harder to use 2. For instance, 839// if current sp is already near the lower end of page 101, and we need to 840// call mmap() to map page 100, it is possible that part of the mmap() frame 841// will be placed in page 100. When page 100 is mapped, it is zero-filled. 842// That will destroy the mmap() frame and cause VM to crash. 843// 844// The following code works by adjusting sp first, then accessing the "bottom" 845// page to force a page fault. Bsd kernel will then automatically expand the 846// stack mapping. 847// 848// _expand_stack_to() assumes its frame size is less than page size, which 849// should always be true if the function is not inlined. 850 851#if __GNUC__ < 3 // gcc 2.x does not support noinline attribute 852#define NOINLINE 853#else 854#define NOINLINE __attribute__ ((noinline)) 855#endif 856 857static void _expand_stack_to(address bottom) NOINLINE; 858 859static void _expand_stack_to(address bottom) { 860 address sp; 861 size_t size; 862 volatile char *p; 863 864 // Adjust bottom to point to the largest address within the same page, it 865 // gives us a one-page buffer if alloca() allocates slightly more memory. 866 bottom = (address)align_size_down((uintptr_t)bottom, os::Bsd::page_size()); 867 bottom += os::Bsd::page_size() - 1; 868 869 // sp might be slightly above current stack pointer; if that's the case, we 870 // will alloca() a little more space than necessary, which is OK. Don't use 871 // os::current_stack_pointer(), as its result can be slightly below current 872 // stack pointer, causing us to not alloca enough to reach "bottom". 873 sp = (address)&sp; 874 875 if (sp > bottom) { 876 size = sp - bottom; 877 p = (volatile char *)alloca(size); 878 assert(p != NULL && p <= (volatile char *)bottom, "alloca problem?"); 879 p[0] = '\0'; 880 } 881} 882 883bool os::Bsd::manually_expand_stack(JavaThread * t, address addr) { 884 assert(t!=NULL, "just checking"); 885 assert(t->osthread()->expanding_stack(), "expand should be set"); 886 assert(t->stack_base() != NULL, "stack_base was not initialized"); 887 888 if (addr < t->stack_base() && addr >= t->stack_yellow_zone_base()) { 889 sigset_t mask_all, old_sigset; 890 sigfillset(&mask_all); 891 pthread_sigmask(SIG_SETMASK, &mask_all, &old_sigset); 892 _expand_stack_to(addr); 893 pthread_sigmask(SIG_SETMASK, &old_sigset, NULL); 894 return true; 895 } 896 return false; 897} 898#endif 899 900////////////////////////////////////////////////////////////////////////////// 901// create new thread 902 903static address highest_vm_reserved_address(); 904 905// check if it's safe to start a new thread 906static bool _thread_safety_check(Thread* thread) { 907#ifdef _ALLBSD_SOURCE 908 return true; 909#else 910 if (os::Bsd::is_BsdThreads() && !os::Bsd::is_floating_stack()) { 911 // Fixed stack BsdThreads (SuSE Bsd/x86, and some versions of Redhat) 912 // Heap is mmap'ed at lower end of memory space. Thread stacks are 913 // allocated (MAP_FIXED) from high address space. Every thread stack 914 // occupies a fixed size slot (usually 2Mbytes, but user can change 915 // it to other values if they rebuild BsdThreads). 916 // 917 // Problem with MAP_FIXED is that mmap() can still succeed even part of 918 // the memory region has already been mmap'ed. That means if we have too 919 // many threads and/or very large heap, eventually thread stack will 920 // collide with heap. 921 // 922 // Here we try to prevent heap/stack collision by comparing current 923 // stack bottom with the highest address that has been mmap'ed by JVM 924 // plus a safety margin for memory maps created by native code. 925 // 926 // This feature can be disabled by setting ThreadSafetyMargin to 0 927 // 928 if (ThreadSafetyMargin > 0) { 929 address stack_bottom = os::current_stack_base() - os::current_stack_size(); 930 931 // not safe if our stack extends below the safety margin 932 return stack_bottom - ThreadSafetyMargin >= highest_vm_reserved_address(); 933 } else { 934 return true; 935 } 936 } else { 937 // Floating stack BsdThreads or NPTL: 938 // Unlike fixed stack BsdThreads, thread stacks are not MAP_FIXED. When 939 // there's not enough space left, pthread_create() will fail. If we come 940 // here, that means enough space has been reserved for stack. 941 return true; 942 } 943#endif 944} 945 946#ifdef __APPLE__ 947// library handle for calling objc_registerThreadWithCollector() 948// without static linking to the libobjc library 949#define OBJC_LIB "/usr/lib/libobjc.dylib" 950#define OBJC_GCREGISTER "objc_registerThreadWithCollector" 951typedef void (*objc_registerThreadWithCollector_t)(); 952extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 953objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 954#endif 955 956// Thread start routine for all newly created threads 957static void *java_start(Thread *thread) { 958 // Try to randomize the cache line index of hot stack frames. 959 // This helps when threads of the same stack traces evict each other's 960 // cache lines. The threads can be either from the same JVM instance, or 961 // from different JVM instances. The benefit is especially true for 962 // processors with hyperthreading technology. 963 static int counter = 0; 964 int pid = os::current_process_id(); 965 alloca(((pid ^ counter++) & 7) * 128); 966 967 ThreadLocalStorage::set_thread(thread); 968 969 OSThread* osthread = thread->osthread(); 970 Monitor* sync = osthread->startThread_lock(); 971 972 // non floating stack BsdThreads needs extra check, see above 973 if (!_thread_safety_check(thread)) { 974 // notify parent thread 975 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 976 osthread->set_state(ZOMBIE); 977 sync->notify_all(); 978 return NULL; 979 } 980 981#ifdef _ALLBSD_SOURCE 982 // thread_id is pthread_id on BSD 983 osthread->set_thread_id(::pthread_self()); 984#else 985 // thread_id is kernel thread id (similar to Solaris LWP id) 986 osthread->set_thread_id(os::Bsd::gettid()); 987 988 if (UseNUMA) { 989 int lgrp_id = os::numa_get_group_id(); 990 if (lgrp_id != -1) { 991 thread->set_lgrp_id(lgrp_id); 992 } 993 } 994#endif 995 // initialize signal mask for this thread 996 os::Bsd::hotspot_sigmask(thread); 997 998 // initialize floating point control register 999 os::Bsd::init_thread_fpu_state(); 1000 1001#ifdef __APPLE__ 1002 // register thread with objc gc 1003 if (objc_registerThreadWithCollectorFunction != NULL) { 1004 objc_registerThreadWithCollectorFunction(); 1005 } 1006#endif 1007 1008 // handshaking with parent thread 1009 { 1010 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 1011 1012 // notify parent thread 1013 osthread->set_state(INITIALIZED); 1014 sync->notify_all(); 1015 1016 // wait until os::start_thread() 1017 while (osthread->get_state() == INITIALIZED) { 1018 sync->wait(Mutex::_no_safepoint_check_flag); 1019 } 1020 } 1021 1022 // call one more level start routine 1023 thread->run(); 1024 1025 return 0; 1026} 1027 1028bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 1029 assert(thread->osthread() == NULL, "caller responsible"); 1030 1031 // Allocate the OSThread object 1032 OSThread* osthread = new OSThread(NULL, NULL); 1033 if (osthread == NULL) { 1034 return false; 1035 } 1036 1037 // set the correct thread state 1038 osthread->set_thread_type(thr_type); 1039 1040 // Initial state is ALLOCATED but not INITIALIZED 1041 osthread->set_state(ALLOCATED); 1042 1043 thread->set_osthread(osthread); 1044 1045 // init thread attributes 1046 pthread_attr_t attr; 1047 pthread_attr_init(&attr); 1048 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 1049 1050 // stack size 1051 if (os::Bsd::supports_variable_stack_size()) { 1052 // calculate stack size if it's not specified by caller 1053 if (stack_size == 0) { 1054 stack_size = os::Bsd::default_stack_size(thr_type); 1055 1056 switch (thr_type) { 1057 case os::java_thread: 1058 // Java threads use ThreadStackSize which default value can be 1059 // changed with the flag -Xss 1060 assert (JavaThread::stack_size_at_create() > 0, "this should be set"); 1061 stack_size = JavaThread::stack_size_at_create(); 1062 break; 1063 case os::compiler_thread: 1064 if (CompilerThreadStackSize > 0) { 1065 stack_size = (size_t)(CompilerThreadStackSize * K); 1066 break; 1067 } // else fall through: 1068 // use VMThreadStackSize if CompilerThreadStackSize is not defined 1069 case os::vm_thread: 1070 case os::pgc_thread: 1071 case os::cgc_thread: 1072 case os::watcher_thread: 1073 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 1074 break; 1075 } 1076 } 1077 1078 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 1079 pthread_attr_setstacksize(&attr, stack_size); 1080 } else { 1081 // let pthread_create() pick the default value. 1082 } 1083 1084#ifndef _ALLBSD_SOURCE 1085 // glibc guard page 1086 pthread_attr_setguardsize(&attr, os::Bsd::default_guard_size(thr_type)); 1087#endif 1088 1089 ThreadState state; 1090 1091 { 1092 1093#ifndef _ALLBSD_SOURCE 1094 // Serialize thread creation if we are running with fixed stack BsdThreads 1095 bool lock = os::Bsd::is_BsdThreads() && !os::Bsd::is_floating_stack(); 1096 if (lock) { 1097 os::Bsd::createThread_lock()->lock_without_safepoint_check(); 1098 } 1099#endif 1100 1101 pthread_t tid; 1102 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 1103 1104 pthread_attr_destroy(&attr); 1105 1106 if (ret != 0) { 1107 if (PrintMiscellaneous && (Verbose || WizardMode)) { 1108 perror("pthread_create()"); 1109 } 1110 // Need to clean up stuff we've allocated so far 1111 thread->set_osthread(NULL); 1112 delete osthread; 1113#ifndef _ALLBSD_SOURCE 1114 if (lock) os::Bsd::createThread_lock()->unlock(); 1115#endif 1116 return false; 1117 } 1118 1119 // Store pthread info into the OSThread 1120 osthread->set_pthread_id(tid); 1121 1122 // Wait until child thread is either initialized or aborted 1123 { 1124 Monitor* sync_with_child = osthread->startThread_lock(); 1125 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 1126 while ((state = osthread->get_state()) == ALLOCATED) { 1127 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 1128 } 1129 } 1130 1131#ifndef _ALLBSD_SOURCE 1132 if (lock) { 1133 os::Bsd::createThread_lock()->unlock(); 1134 } 1135#endif 1136 } 1137 1138 // Aborted due to thread limit being reached 1139 if (state == ZOMBIE) { 1140 thread->set_osthread(NULL); 1141 delete osthread; 1142 return false; 1143 } 1144 1145 // The thread is returned suspended (in state INITIALIZED), 1146 // and is started higher up in the call chain 1147 assert(state == INITIALIZED, "race condition"); 1148 return true; 1149} 1150 1151///////////////////////////////////////////////////////////////////////////// 1152// attach existing thread 1153 1154// bootstrap the main thread 1155bool os::create_main_thread(JavaThread* thread) { 1156 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 1157 return create_attached_thread(thread); 1158} 1159 1160bool os::create_attached_thread(JavaThread* thread) { 1161#ifdef ASSERT 1162 thread->verify_not_published(); 1163#endif 1164 1165 // Allocate the OSThread object 1166 OSThread* osthread = new OSThread(NULL, NULL); 1167 1168 if (osthread == NULL) { 1169 return false; 1170 } 1171 1172 // Store pthread info into the OSThread 1173#ifdef _ALLBSD_SOURCE 1174 osthread->set_thread_id(::pthread_self()); 1175#else 1176 osthread->set_thread_id(os::Bsd::gettid()); 1177#endif 1178 osthread->set_pthread_id(::pthread_self()); 1179 1180 // initialize floating point control register 1181 os::Bsd::init_thread_fpu_state(); 1182 1183 // Initial thread state is RUNNABLE 1184 osthread->set_state(RUNNABLE); 1185 1186 thread->set_osthread(osthread); 1187 1188#ifndef _ALLBSD_SOURCE 1189 if (UseNUMA) { 1190 int lgrp_id = os::numa_get_group_id(); 1191 if (lgrp_id != -1) { 1192 thread->set_lgrp_id(lgrp_id); 1193 } 1194 } 1195 1196 if (os::Bsd::is_initial_thread()) { 1197 // If current thread is initial thread, its stack is mapped on demand, 1198 // see notes about MAP_GROWSDOWN. Here we try to force kernel to map 1199 // the entire stack region to avoid SEGV in stack banging. 1200 // It is also useful to get around the heap-stack-gap problem on SuSE 1201 // kernel (see 4821821 for details). We first expand stack to the top 1202 // of yellow zone, then enable stack yellow zone (order is significant, 1203 // enabling yellow zone first will crash JVM on SuSE Bsd), so there 1204 // is no gap between the last two virtual memory regions. 1205 1206 JavaThread *jt = (JavaThread *)thread; 1207 address addr = jt->stack_yellow_zone_base(); 1208 assert(addr != NULL, "initialization problem?"); 1209 assert(jt->stack_available(addr) > 0, "stack guard should not be enabled"); 1210 1211 osthread->set_expanding_stack(); 1212 os::Bsd::manually_expand_stack(jt, addr); 1213 osthread->clear_expanding_stack(); 1214 } 1215#endif 1216 1217 // initialize signal mask for this thread 1218 // and save the caller's signal mask 1219 os::Bsd::hotspot_sigmask(thread); 1220 1221 return true; 1222} 1223 1224void os::pd_start_thread(Thread* thread) { 1225 OSThread * osthread = thread->osthread(); 1226 assert(osthread->get_state() != INITIALIZED, "just checking"); 1227 Monitor* sync_with_child = osthread->startThread_lock(); 1228 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 1229 sync_with_child->notify(); 1230} 1231 1232// Free Bsd resources related to the OSThread 1233void os::free_thread(OSThread* osthread) { 1234 assert(osthread != NULL, "osthread not set"); 1235 1236 if (Thread::current()->osthread() == osthread) { 1237 // Restore caller's signal mask 1238 sigset_t sigmask = osthread->caller_sigmask(); 1239 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 1240 } 1241 1242 delete osthread; 1243} 1244 1245////////////////////////////////////////////////////////////////////////////// 1246// thread local storage 1247 1248int os::allocate_thread_local_storage() { 1249 pthread_key_t key; 1250 int rslt = pthread_key_create(&key, NULL); 1251 assert(rslt == 0, "cannot allocate thread local storage"); 1252 return (int)key; 1253} 1254 1255// Note: This is currently not used by VM, as we don't destroy TLS key 1256// on VM exit. 1257void os::free_thread_local_storage(int index) { 1258 int rslt = pthread_key_delete((pthread_key_t)index); 1259 assert(rslt == 0, "invalid index"); 1260} 1261 1262void os::thread_local_storage_at_put(int index, void* value) { 1263 int rslt = pthread_setspecific((pthread_key_t)index, value); 1264 assert(rslt == 0, "pthread_setspecific failed"); 1265} 1266 1267extern "C" Thread* get_thread() { 1268 return ThreadLocalStorage::thread(); 1269} 1270 1271////////////////////////////////////////////////////////////////////////////// 1272// initial thread 1273 1274#ifndef _ALLBSD_SOURCE 1275// Check if current thread is the initial thread, similar to Solaris thr_main. 1276bool os::Bsd::is_initial_thread(void) { 1277 char dummy; 1278 // If called before init complete, thread stack bottom will be null. 1279 // Can be called if fatal error occurs before initialization. 1280 if (initial_thread_stack_bottom() == NULL) return false; 1281 assert(initial_thread_stack_bottom() != NULL && 1282 initial_thread_stack_size() != 0, 1283 "os::init did not locate initial thread's stack region"); 1284 if ((address)&dummy >= initial_thread_stack_bottom() && 1285 (address)&dummy < initial_thread_stack_bottom() + initial_thread_stack_size()) 1286 return true; 1287 else return false; 1288} 1289 1290// Find the virtual memory area that contains addr 1291static bool find_vma(address addr, address* vma_low, address* vma_high) { 1292 FILE *fp = fopen("/proc/self/maps", "r"); 1293 if (fp) { 1294 address low, high; 1295 while (!feof(fp)) { 1296 if (fscanf(fp, "%p-%p", &low, &high) == 2) { 1297 if (low <= addr && addr < high) { 1298 if (vma_low) *vma_low = low; 1299 if (vma_high) *vma_high = high; 1300 fclose (fp); 1301 return true; 1302 } 1303 } 1304 for (;;) { 1305 int ch = fgetc(fp); 1306 if (ch == EOF || ch == (int)'\n') break; 1307 } 1308 } 1309 fclose(fp); 1310 } 1311 return false; 1312} 1313 1314// Locate initial thread stack. This special handling of initial thread stack 1315// is needed because pthread_getattr_np() on most (all?) Bsd distros returns 1316// bogus value for initial thread. 1317void os::Bsd::capture_initial_stack(size_t max_size) { 1318 // stack size is the easy part, get it from RLIMIT_STACK 1319 size_t stack_size; 1320 struct rlimit rlim; 1321 getrlimit(RLIMIT_STACK, &rlim); 1322 stack_size = rlim.rlim_cur; 1323 1324 // 6308388: a bug in ld.so will relocate its own .data section to the 1325 // lower end of primordial stack; reduce ulimit -s value a little bit 1326 // so we won't install guard page on ld.so's data section. 1327 stack_size -= 2 * page_size(); 1328 1329 // 4441425: avoid crash with "unlimited" stack size on SuSE 7.1 or Redhat 1330 // 7.1, in both cases we will get 2G in return value. 1331 // 4466587: glibc 2.2.x compiled w/o "--enable-kernel=2.4.0" (RH 7.0, 1332 // SuSE 7.2, Debian) can not handle alternate signal stack correctly 1333 // for initial thread if its stack size exceeds 6M. Cap it at 2M, 1334 // in case other parts in glibc still assumes 2M max stack size. 1335 // FIXME: alt signal stack is gone, maybe we can relax this constraint? 1336#ifndef IA64 1337 if (stack_size > 2 * K * K) stack_size = 2 * K * K; 1338#else 1339 // Problem still exists RH7.2 (IA64 anyway) but 2MB is a little small 1340 if (stack_size > 4 * K * K) stack_size = 4 * K * K; 1341#endif 1342 1343 // Try to figure out where the stack base (top) is. This is harder. 1344 // 1345 // When an application is started, glibc saves the initial stack pointer in 1346 // a global variable "__libc_stack_end", which is then used by system 1347 // libraries. __libc_stack_end should be pretty close to stack top. The 1348 // variable is available since the very early days. However, because it is 1349 // a private interface, it could disappear in the future. 1350 // 1351 // Bsd kernel saves start_stack information in /proc/<pid>/stat. Similar 1352 // to __libc_stack_end, it is very close to stack top, but isn't the real 1353 // stack top. Note that /proc may not exist if VM is running as a chroot 1354 // program, so reading /proc/<pid>/stat could fail. Also the contents of 1355 // /proc/<pid>/stat could change in the future (though unlikely). 1356 // 1357 // We try __libc_stack_end first. If that doesn't work, look for 1358 // /proc/<pid>/stat. If neither of them works, we use current stack pointer 1359 // as a hint, which should work well in most cases. 1360 1361 uintptr_t stack_start; 1362 1363 // try __libc_stack_end first 1364 uintptr_t *p = (uintptr_t *)dlsym(RTLD_DEFAULT, "__libc_stack_end"); 1365 if (p && *p) { 1366 stack_start = *p; 1367 } else { 1368 // see if we can get the start_stack field from /proc/self/stat 1369 FILE *fp; 1370 int pid; 1371 char state; 1372 int ppid; 1373 int pgrp; 1374 int session; 1375 int nr; 1376 int tpgrp; 1377 unsigned long flags; 1378 unsigned long minflt; 1379 unsigned long cminflt; 1380 unsigned long majflt; 1381 unsigned long cmajflt; 1382 unsigned long utime; 1383 unsigned long stime; 1384 long cutime; 1385 long cstime; 1386 long prio; 1387 long nice; 1388 long junk; 1389 long it_real; 1390 uintptr_t start; 1391 uintptr_t vsize; 1392 intptr_t rss; 1393 uintptr_t rsslim; 1394 uintptr_t scodes; 1395 uintptr_t ecode; 1396 int i; 1397 1398 // Figure what the primordial thread stack base is. Code is inspired 1399 // by email from Hans Boehm. /proc/self/stat begins with current pid, 1400 // followed by command name surrounded by parentheses, state, etc. 1401 char stat[2048]; 1402 int statlen; 1403 1404 fp = fopen("/proc/self/stat", "r"); 1405 if (fp) { 1406 statlen = fread(stat, 1, 2047, fp); 1407 stat[statlen] = '\0'; 1408 fclose(fp); 1409 1410 // Skip pid and the command string. Note that we could be dealing with 1411 // weird command names, e.g. user could decide to rename java launcher 1412 // to "java 1.4.2 :)", then the stat file would look like 1413 // 1234 (java 1.4.2 :)) R ... ... 1414 // We don't really need to know the command string, just find the last 1415 // occurrence of ")" and then start parsing from there. See bug 4726580. 1416 char * s = strrchr(stat, ')'); 1417 1418 i = 0; 1419 if (s) { 1420 // Skip blank chars 1421 do s++; while (isspace(*s)); 1422 1423#define _UFM UINTX_FORMAT 1424#define _DFM INTX_FORMAT 1425 1426 /* 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 */ 1427 /* 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 */ 1428 i = sscanf(s, "%c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu %ld %ld %ld %ld %ld %ld " _UFM _UFM _DFM _UFM _UFM _UFM _UFM, 1429 &state, /* 3 %c */ 1430 &ppid, /* 4 %d */ 1431 &pgrp, /* 5 %d */ 1432 &session, /* 6 %d */ 1433 &nr, /* 7 %d */ 1434 &tpgrp, /* 8 %d */ 1435 &flags, /* 9 %lu */ 1436 &minflt, /* 10 %lu */ 1437 &cminflt, /* 11 %lu */ 1438 &majflt, /* 12 %lu */ 1439 &cmajflt, /* 13 %lu */ 1440 &utime, /* 14 %lu */ 1441 &stime, /* 15 %lu */ 1442 &cutime, /* 16 %ld */ 1443 &cstime, /* 17 %ld */ 1444 &prio, /* 18 %ld */ 1445 &nice, /* 19 %ld */ 1446 &junk, /* 20 %ld */ 1447 &it_real, /* 21 %ld */ 1448 &start, /* 22 UINTX_FORMAT */ 1449 &vsize, /* 23 UINTX_FORMAT */ 1450 &rss, /* 24 INTX_FORMAT */ 1451 &rsslim, /* 25 UINTX_FORMAT */ 1452 &scodes, /* 26 UINTX_FORMAT */ 1453 &ecode, /* 27 UINTX_FORMAT */ 1454 &stack_start); /* 28 UINTX_FORMAT */ 1455 } 1456 1457#undef _UFM 1458#undef _DFM 1459 1460 if (i != 28 - 2) { 1461 assert(false, "Bad conversion from /proc/self/stat"); 1462 // product mode - assume we are the initial thread, good luck in the 1463 // embedded case. 1464 warning("Can't detect initial thread stack location - bad conversion"); 1465 stack_start = (uintptr_t) &rlim; 1466 } 1467 } else { 1468 // For some reason we can't open /proc/self/stat (for example, running on 1469 // FreeBSD with a Bsd emulator, or inside chroot), this should work for 1470 // most cases, so don't abort: 1471 warning("Can't detect initial thread stack location - no /proc/self/stat"); 1472 stack_start = (uintptr_t) &rlim; 1473 } 1474 } 1475 1476 // Now we have a pointer (stack_start) very close to the stack top, the 1477 // next thing to do is to figure out the exact location of stack top. We 1478 // can find out the virtual memory area that contains stack_start by 1479 // reading /proc/self/maps, it should be the last vma in /proc/self/maps, 1480 // and its upper limit is the real stack top. (again, this would fail if 1481 // running inside chroot, because /proc may not exist.) 1482 1483 uintptr_t stack_top; 1484 address low, high; 1485 if (find_vma((address)stack_start, &low, &high)) { 1486 // success, "high" is the true stack top. (ignore "low", because initial 1487 // thread stack grows on demand, its real bottom is high - RLIMIT_STACK.) 1488 stack_top = (uintptr_t)high; 1489 } else { 1490 // failed, likely because /proc/self/maps does not exist 1491 warning("Can't detect initial thread stack location - find_vma failed"); 1492 // best effort: stack_start is normally within a few pages below the real 1493 // stack top, use it as stack top, and reduce stack size so we won't put 1494 // guard page outside stack. 1495 stack_top = stack_start; 1496 stack_size -= 16 * page_size(); 1497 } 1498 1499 // stack_top could be partially down the page so align it 1500 stack_top = align_size_up(stack_top, page_size()); 1501 1502 if (max_size && stack_size > max_size) { 1503 _initial_thread_stack_size = max_size; 1504 } else { 1505 _initial_thread_stack_size = stack_size; 1506 } 1507 1508 _initial_thread_stack_size = align_size_down(_initial_thread_stack_size, page_size()); 1509 _initial_thread_stack_bottom = (address)stack_top - _initial_thread_stack_size; 1510} 1511#endif 1512 1513//////////////////////////////////////////////////////////////////////////////// 1514// time support 1515 1516// Time since start-up in seconds to a fine granularity. 1517// Used by VMSelfDestructTimer and the MemProfiler. 1518double os::elapsedTime() { 1519 1520 return (double)(os::elapsed_counter()) * 0.000001; 1521} 1522 1523jlong os::elapsed_counter() { 1524 timeval time; 1525 int status = gettimeofday(&time, NULL); 1526 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count; 1527} 1528 1529jlong os::elapsed_frequency() { 1530 return (1000 * 1000); 1531} 1532 1533// XXX: For now, code this as if BSD does not support vtime. 1534bool os::supports_vtime() { return false; } 1535bool os::enable_vtime() { return false; } 1536bool os::vtime_enabled() { return false; } 1537double os::elapsedVTime() { 1538 // better than nothing, but not much 1539 return elapsedTime(); 1540} 1541 1542jlong os::javaTimeMillis() { 1543 timeval time; 1544 int status = gettimeofday(&time, NULL); 1545 assert(status != -1, "bsd error"); 1546 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 1547} 1548 1549#ifndef CLOCK_MONOTONIC 1550#define CLOCK_MONOTONIC (1) 1551#endif 1552 1553#ifdef __APPLE__ 1554void os::Bsd::clock_init() { 1555 // XXXDARWIN: Investigate replacement monotonic clock 1556} 1557#elif defined(_ALLBSD_SOURCE) 1558void os::Bsd::clock_init() { 1559 struct timespec res; 1560 struct timespec tp; 1561 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 1562 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 1563 // yes, monotonic clock is supported 1564 _clock_gettime = ::clock_gettime; 1565 } 1566} 1567#else 1568void os::Bsd::clock_init() { 1569 // we do dlopen's in this particular order due to bug in bsd 1570 // dynamical loader (see 6348968) leading to crash on exit 1571 void* handle = dlopen("librt.so.1", RTLD_LAZY); 1572 if (handle == NULL) { 1573 handle = dlopen("librt.so", RTLD_LAZY); 1574 } 1575 1576 if (handle) { 1577 int (*clock_getres_func)(clockid_t, struct timespec*) = 1578 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_getres"); 1579 int (*clock_gettime_func)(clockid_t, struct timespec*) = 1580 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_gettime"); 1581 if (clock_getres_func && clock_gettime_func) { 1582 // See if monotonic clock is supported by the kernel. Note that some 1583 // early implementations simply return kernel jiffies (updated every 1584 // 1/100 or 1/1000 second). It would be bad to use such a low res clock 1585 // for nano time (though the monotonic property is still nice to have). 1586 // It's fixed in newer kernels, however clock_getres() still returns 1587 // 1/HZ. We check if clock_getres() works, but will ignore its reported 1588 // resolution for now. Hopefully as people move to new kernels, this 1589 // won't be a problem. 1590 struct timespec res; 1591 struct timespec tp; 1592 if (clock_getres_func (CLOCK_MONOTONIC, &res) == 0 && 1593 clock_gettime_func(CLOCK_MONOTONIC, &tp) == 0) { 1594 // yes, monotonic clock is supported 1595 _clock_gettime = clock_gettime_func; 1596 } else { 1597 // close librt if there is no monotonic clock 1598 dlclose(handle); 1599 } 1600 } 1601 } 1602} 1603#endif 1604 1605#ifndef _ALLBSD_SOURCE 1606#ifndef SYS_clock_getres 1607 1608#if defined(IA32) || defined(AMD64) 1609#define SYS_clock_getres IA32_ONLY(266) AMD64_ONLY(229) 1610#define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y) 1611#else 1612#warning "SYS_clock_getres not defined for this platform, disabling fast_thread_cpu_time" 1613#define sys_clock_getres(x,y) -1 1614#endif 1615 1616#else 1617#define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y) 1618#endif 1619 1620void os::Bsd::fast_thread_clock_init() { 1621 if (!UseBsdPosixThreadCPUClocks) { 1622 return; 1623 } 1624 clockid_t clockid; 1625 struct timespec tp; 1626 int (*pthread_getcpuclockid_func)(pthread_t, clockid_t *) = 1627 (int(*)(pthread_t, clockid_t *)) dlsym(RTLD_DEFAULT, "pthread_getcpuclockid"); 1628 1629 // Switch to using fast clocks for thread cpu time if 1630 // the sys_clock_getres() returns 0 error code. 1631 // Note, that some kernels may support the current thread 1632 // clock (CLOCK_THREAD_CPUTIME_ID) but not the clocks 1633 // returned by the pthread_getcpuclockid(). 1634 // If the fast Posix clocks are supported then the sys_clock_getres() 1635 // must return at least tp.tv_sec == 0 which means a resolution 1636 // better than 1 sec. This is extra check for reliability. 1637 1638 if(pthread_getcpuclockid_func && 1639 pthread_getcpuclockid_func(_main_thread, &clockid) == 0 && 1640 sys_clock_getres(clockid, &tp) == 0 && tp.tv_sec == 0) { 1641 1642 _supports_fast_thread_cpu_time = true; 1643 _pthread_getcpuclockid = pthread_getcpuclockid_func; 1644 } 1645} 1646#endif 1647 1648jlong os::javaTimeNanos() { 1649 if (Bsd::supports_monotonic_clock()) { 1650 struct timespec tp; 1651 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp); 1652 assert(status == 0, "gettime error"); 1653 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1654 return result; 1655 } else { 1656 timeval time; 1657 int status = gettimeofday(&time, NULL); 1658 assert(status != -1, "bsd error"); 1659 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1660 return 1000 * usecs; 1661 } 1662} 1663 1664void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1665 if (Bsd::supports_monotonic_clock()) { 1666 info_ptr->max_value = ALL_64_BITS; 1667 1668 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1669 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1670 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1671 } else { 1672 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1673 info_ptr->max_value = ALL_64_BITS; 1674 1675 // gettimeofday is a real time clock so it skips 1676 info_ptr->may_skip_backward = true; 1677 info_ptr->may_skip_forward = true; 1678 } 1679 1680 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1681} 1682 1683// Return the real, user, and system times in seconds from an 1684// arbitrary fixed point in the past. 1685bool os::getTimesSecs(double* process_real_time, 1686 double* process_user_time, 1687 double* process_system_time) { 1688 struct tms ticks; 1689 clock_t real_ticks = times(&ticks); 1690 1691 if (real_ticks == (clock_t) (-1)) { 1692 return false; 1693 } else { 1694 double ticks_per_second = (double) clock_tics_per_sec; 1695 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1696 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1697 *process_real_time = ((double) real_ticks) / ticks_per_second; 1698 1699 return true; 1700 } 1701} 1702 1703 1704char * os::local_time_string(char *buf, size_t buflen) { 1705 struct tm t; 1706 time_t long_time; 1707 time(&long_time); 1708 localtime_r(&long_time, &t); 1709 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1710 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1711 t.tm_hour, t.tm_min, t.tm_sec); 1712 return buf; 1713} 1714 1715struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1716 return localtime_r(clock, res); 1717} 1718 1719//////////////////////////////////////////////////////////////////////////////// 1720// runtime exit support 1721 1722// Note: os::shutdown() might be called very early during initialization, or 1723// called from signal handler. Before adding something to os::shutdown(), make 1724// sure it is async-safe and can handle partially initialized VM. 1725void os::shutdown() { 1726 1727 // allow PerfMemory to attempt cleanup of any persistent resources 1728 perfMemory_exit(); 1729 1730 // needs to remove object in file system 1731 AttachListener::abort(); 1732 1733 // flush buffered output, finish log files 1734 ostream_abort(); 1735 1736 // Check for abort hook 1737 abort_hook_t abort_hook = Arguments::abort_hook(); 1738 if (abort_hook != NULL) { 1739 abort_hook(); 1740 } 1741 1742} 1743 1744// Note: os::abort() might be called very early during initialization, or 1745// called from signal handler. Before adding something to os::abort(), make 1746// sure it is async-safe and can handle partially initialized VM. 1747void os::abort(bool dump_core) { 1748 os::shutdown(); 1749 if (dump_core) { 1750#ifndef PRODUCT 1751 fdStream out(defaultStream::output_fd()); 1752 out.print_raw("Current thread is "); 1753 char buf[16]; 1754 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1755 out.print_raw_cr(buf); 1756 out.print_raw_cr("Dumping core ..."); 1757#endif 1758 ::abort(); // dump core 1759 } 1760 1761 ::exit(1); 1762} 1763 1764// Die immediately, no exit hook, no abort hook, no cleanup. 1765void os::die() { 1766 // _exit() on BsdThreads only kills current thread 1767 ::abort(); 1768} 1769 1770// unused on bsd for now. 1771void os::set_error_file(const char *logfile) {} 1772 1773 1774// This method is a copy of JDK's sysGetLastErrorString 1775// from src/solaris/hpi/src/system_md.c 1776 1777size_t os::lasterror(char *buf, size_t len) { 1778 1779 if (errno == 0) return 0; 1780 1781 const char *s = ::strerror(errno); 1782 size_t n = ::strlen(s); 1783 if (n >= len) { 1784 n = len - 1; 1785 } 1786 ::strncpy(buf, s, n); 1787 buf[n] = '\0'; 1788 return n; 1789} 1790 1791intx os::current_thread_id() { return (intx)pthread_self(); } 1792int os::current_process_id() { 1793 1794 // Under the old bsd thread library, bsd gives each thread 1795 // its own process id. Because of this each thread will return 1796 // a different pid if this method were to return the result 1797 // of getpid(2). Bsd provides no api that returns the pid 1798 // of the launcher thread for the vm. This implementation 1799 // returns a unique pid, the pid of the launcher thread 1800 // that starts the vm 'process'. 1801 1802 // Under the NPTL, getpid() returns the same pid as the 1803 // launcher thread rather than a unique pid per thread. 1804 // Use gettid() if you want the old pre NPTL behaviour. 1805 1806 // if you are looking for the result of a call to getpid() that 1807 // returns a unique pid for the calling thread, then look at the 1808 // OSThread::thread_id() method in osThread_bsd.hpp file 1809 1810 return (int)(_initial_pid ? _initial_pid : getpid()); 1811} 1812 1813// DLL functions 1814 1815#define JNI_LIB_PREFIX "lib" 1816#ifdef __APPLE__ 1817#define JNI_LIB_SUFFIX ".dylib" 1818#else 1819#define JNI_LIB_SUFFIX ".so" 1820#endif 1821 1822const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1823 1824// This must be hard coded because it's the system's temporary 1825// directory not the java application's temp directory, ala java.io.tmpdir. 1826#ifdef __APPLE__ 1827// macosx has a secure per-user temporary directory 1828char temp_path_storage[PATH_MAX]; 1829const char* os::get_temp_directory() { 1830 static char *temp_path = NULL; 1831 if (temp_path == NULL) { 1832 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1833 if (pathSize == 0 || pathSize > PATH_MAX) { 1834 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1835 } 1836 temp_path = temp_path_storage; 1837 } 1838 return temp_path; 1839} 1840#else /* __APPLE__ */ 1841const char* os::get_temp_directory() { return "/tmp"; } 1842#endif /* __APPLE__ */ 1843 1844static bool file_exists(const char* filename) { 1845 struct stat statbuf; 1846 if (filename == NULL || strlen(filename) == 0) { 1847 return false; 1848 } 1849 return os::stat(filename, &statbuf) == 0; 1850} 1851 1852void os::dll_build_name(char* buffer, size_t buflen, 1853 const char* pname, const char* fname) { 1854 // Copied from libhpi 1855 const size_t pnamelen = pname ? strlen(pname) : 0; 1856 1857 // Quietly truncate on buffer overflow. Should be an error. 1858 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1859 *buffer = '\0'; 1860 return; 1861 } 1862 1863 if (pnamelen == 0) { 1864 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1865 } else if (strchr(pname, *os::path_separator()) != NULL) { 1866 int n; 1867 char** pelements = split_path(pname, &n); 1868 for (int i = 0 ; i < n ; i++) { 1869 // Really shouldn't be NULL, but check can't hurt 1870 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1871 continue; // skip the empty path values 1872 } 1873 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1874 pelements[i], fname); 1875 if (file_exists(buffer)) { 1876 break; 1877 } 1878 } 1879 // release the storage 1880 for (int i = 0 ; i < n ; i++) { 1881 if (pelements[i] != NULL) { 1882 FREE_C_HEAP_ARRAY(char, pelements[i]); 1883 } 1884 } 1885 if (pelements != NULL) { 1886 FREE_C_HEAP_ARRAY(char*, pelements); 1887 } 1888 } else { 1889 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1890 } 1891} 1892 1893const char* os::get_current_directory(char *buf, int buflen) { 1894 return getcwd(buf, buflen); 1895} 1896 1897// check if addr is inside libjvm[_g].so 1898bool os::address_is_in_vm(address addr) { 1899 static address libjvm_base_addr; 1900 Dl_info dlinfo; 1901 1902 if (libjvm_base_addr == NULL) { 1903 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo); 1904 libjvm_base_addr = (address)dlinfo.dli_fbase; 1905 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1906 } 1907 1908 if (dladdr((void *)addr, &dlinfo)) { 1909 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1910 } 1911 1912 return false; 1913} 1914 1915bool os::dll_address_to_function_name(address addr, char *buf, 1916 int buflen, int *offset) { 1917 Dl_info dlinfo; 1918 1919 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) { 1920 if (buf != NULL) { 1921 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1922 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1923 } 1924 } 1925 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1926 return true; 1927 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) { 1928 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1929 buf, buflen, offset, dlinfo.dli_fname)) { 1930 return true; 1931 } 1932 } 1933 1934 if (buf != NULL) buf[0] = '\0'; 1935 if (offset != NULL) *offset = -1; 1936 return false; 1937} 1938 1939#ifdef _ALLBSD_SOURCE 1940// ported from solaris version 1941bool os::dll_address_to_library_name(address addr, char* buf, 1942 int buflen, int* offset) { 1943 Dl_info dlinfo; 1944 1945 if (dladdr((void*)addr, &dlinfo)){ 1946 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1947 if (offset) *offset = addr - (address)dlinfo.dli_fbase; 1948 return true; 1949 } else { 1950 if (buf) buf[0] = '\0'; 1951 if (offset) *offset = -1; 1952 return false; 1953 } 1954} 1955#else 1956struct _address_to_library_name { 1957 address addr; // input : memory address 1958 size_t buflen; // size of fname 1959 char* fname; // output: library name 1960 address base; // library base addr 1961}; 1962 1963static int address_to_library_name_callback(struct dl_phdr_info *info, 1964 size_t size, void *data) { 1965 int i; 1966 bool found = false; 1967 address libbase = NULL; 1968 struct _address_to_library_name * d = (struct _address_to_library_name *)data; 1969 1970 // iterate through all loadable segments 1971 for (i = 0; i < info->dlpi_phnum; i++) { 1972 address segbase = (address)(info->dlpi_addr + info->dlpi_phdr[i].p_vaddr); 1973 if (info->dlpi_phdr[i].p_type == PT_LOAD) { 1974 // base address of a library is the lowest address of its loaded 1975 // segments. 1976 if (libbase == NULL || libbase > segbase) { 1977 libbase = segbase; 1978 } 1979 // see if 'addr' is within current segment 1980 if (segbase <= d->addr && 1981 d->addr < segbase + info->dlpi_phdr[i].p_memsz) { 1982 found = true; 1983 } 1984 } 1985 } 1986 1987 // dlpi_name is NULL or empty if the ELF file is executable, return 0 1988 // so dll_address_to_library_name() can fall through to use dladdr() which 1989 // can figure out executable name from argv[0]. 1990 if (found && info->dlpi_name && info->dlpi_name[0]) { 1991 d->base = libbase; 1992 if (d->fname) { 1993 jio_snprintf(d->fname, d->buflen, "%s", info->dlpi_name); 1994 } 1995 return 1; 1996 } 1997 return 0; 1998} 1999 2000bool os::dll_address_to_library_name(address addr, char* buf, 2001 int buflen, int* offset) { 2002 Dl_info dlinfo; 2003 struct _address_to_library_name data; 2004 2005 // There is a bug in old glibc dladdr() implementation that it could resolve 2006 // to wrong library name if the .so file has a base address != NULL. Here 2007 // we iterate through the program headers of all loaded libraries to find 2008 // out which library 'addr' really belongs to. This workaround can be 2009 // removed once the minimum requirement for glibc is moved to 2.3.x. 2010 data.addr = addr; 2011 data.fname = buf; 2012 data.buflen = buflen; 2013 data.base = NULL; 2014 int rslt = dl_iterate_phdr(address_to_library_name_callback, (void *)&data); 2015 2016 if (rslt) { 2017 // buf already contains library name 2018 if (offset) *offset = addr - data.base; 2019 return true; 2020 } else if (dladdr((void*)addr, &dlinfo)){ 2021 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 2022 if (offset) *offset = addr - (address)dlinfo.dli_fbase; 2023 return true; 2024 } else { 2025 if (buf) buf[0] = '\0'; 2026 if (offset) *offset = -1; 2027 return false; 2028 } 2029} 2030#endif 2031 2032 // Loads .dll/.so and 2033 // in case of error it checks if .dll/.so was built for the 2034 // same architecture as Hotspot is running on 2035 2036#ifdef __APPLE__ 2037void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 2038 void * result= ::dlopen(filename, RTLD_LAZY); 2039 if (result != NULL) { 2040 // Successful loading 2041 return result; 2042 } 2043 2044 // Read system error message into ebuf 2045 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 2046 ebuf[ebuflen-1]='\0'; 2047 2048 return NULL; 2049} 2050#else 2051void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 2052{ 2053 void * result= ::dlopen(filename, RTLD_LAZY); 2054 if (result != NULL) { 2055 // Successful loading 2056 return result; 2057 } 2058 2059 Elf32_Ehdr elf_head; 2060 2061 // Read system error message into ebuf 2062 // It may or may not be overwritten below 2063 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 2064 ebuf[ebuflen-1]='\0'; 2065 int diag_msg_max_length=ebuflen-strlen(ebuf); 2066 char* diag_msg_buf=ebuf+strlen(ebuf); 2067 2068 if (diag_msg_max_length==0) { 2069 // No more space in ebuf for additional diagnostics message 2070 return NULL; 2071 } 2072 2073 2074 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 2075 2076 if (file_descriptor < 0) { 2077 // Can't open library, report dlerror() message 2078 return NULL; 2079 } 2080 2081 bool failed_to_read_elf_head= 2082 (sizeof(elf_head)!= 2083 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 2084 2085 ::close(file_descriptor); 2086 if (failed_to_read_elf_head) { 2087 // file i/o error - report dlerror() msg 2088 return NULL; 2089 } 2090 2091 typedef struct { 2092 Elf32_Half code; // Actual value as defined in elf.h 2093 Elf32_Half compat_class; // Compatibility of archs at VM's sense 2094 char elf_class; // 32 or 64 bit 2095 char endianess; // MSB or LSB 2096 char* name; // String representation 2097 } arch_t; 2098 2099 #ifndef EM_486 2100 #define EM_486 6 /* Intel 80486 */ 2101 #endif 2102 2103 #ifndef EM_MIPS_RS3_LE 2104 #define EM_MIPS_RS3_LE 10 /* MIPS */ 2105 #endif 2106 2107 #ifndef EM_PPC64 2108 #define EM_PPC64 21 /* PowerPC64 */ 2109 #endif 2110 2111 #ifndef EM_S390 2112 #define EM_S390 22 /* IBM System/390 */ 2113 #endif 2114 2115 #ifndef EM_IA_64 2116 #define EM_IA_64 50 /* HP/Intel IA-64 */ 2117 #endif 2118 2119 #ifndef EM_X86_64 2120 #define EM_X86_64 62 /* AMD x86-64 */ 2121 #endif 2122 2123 static const arch_t arch_array[]={ 2124 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 2125 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 2126 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 2127 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 2128 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 2129 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 2130 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 2131 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 2132 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 2133 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 2134 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 2135 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 2136 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 2137 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 2138 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 2139 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 2140 }; 2141 2142 #if (defined IA32) 2143 static Elf32_Half running_arch_code=EM_386; 2144 #elif (defined AMD64) 2145 static Elf32_Half running_arch_code=EM_X86_64; 2146 #elif (defined IA64) 2147 static Elf32_Half running_arch_code=EM_IA_64; 2148 #elif (defined __sparc) && (defined _LP64) 2149 static Elf32_Half running_arch_code=EM_SPARCV9; 2150 #elif (defined __sparc) && (!defined _LP64) 2151 static Elf32_Half running_arch_code=EM_SPARC; 2152 #elif (defined __powerpc64__) 2153 static Elf32_Half running_arch_code=EM_PPC64; 2154 #elif (defined __powerpc__) 2155 static Elf32_Half running_arch_code=EM_PPC; 2156 #elif (defined ARM) 2157 static Elf32_Half running_arch_code=EM_ARM; 2158 #elif (defined S390) 2159 static Elf32_Half running_arch_code=EM_S390; 2160 #elif (defined ALPHA) 2161 static Elf32_Half running_arch_code=EM_ALPHA; 2162 #elif (defined MIPSEL) 2163 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 2164 #elif (defined PARISC) 2165 static Elf32_Half running_arch_code=EM_PARISC; 2166 #elif (defined MIPS) 2167 static Elf32_Half running_arch_code=EM_MIPS; 2168 #elif (defined M68K) 2169 static Elf32_Half running_arch_code=EM_68K; 2170 #else 2171 #error Method os::dll_load requires that one of following is defined:\ 2172 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 2173 #endif 2174 2175 // Identify compatability class for VM's architecture and library's architecture 2176 // Obtain string descriptions for architectures 2177 2178 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 2179 int running_arch_index=-1; 2180 2181 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 2182 if (running_arch_code == arch_array[i].code) { 2183 running_arch_index = i; 2184 } 2185 if (lib_arch.code == arch_array[i].code) { 2186 lib_arch.compat_class = arch_array[i].compat_class; 2187 lib_arch.name = arch_array[i].name; 2188 } 2189 } 2190 2191 assert(running_arch_index != -1, 2192 "Didn't find running architecture code (running_arch_code) in arch_array"); 2193 if (running_arch_index == -1) { 2194 // Even though running architecture detection failed 2195 // we may still continue with reporting dlerror() message 2196 return NULL; 2197 } 2198 2199 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 2200 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 2201 return NULL; 2202 } 2203 2204#ifndef S390 2205 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 2206 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 2207 return NULL; 2208 } 2209#endif // !S390 2210 2211 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 2212 if ( lib_arch.name!=NULL ) { 2213 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 2214 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 2215 lib_arch.name, arch_array[running_arch_index].name); 2216 } else { 2217 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 2218 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 2219 lib_arch.code, 2220 arch_array[running_arch_index].name); 2221 } 2222 } 2223 2224 return NULL; 2225} 2226#endif /* !__APPLE__ */ 2227 2228// XXX: Do we need a lock around this as per Linux? 2229void* os::dll_lookup(void* handle, const char* name) { 2230 return dlsym(handle, name); 2231} 2232 2233 2234static bool _print_ascii_file(const char* filename, outputStream* st) { 2235 int fd = ::open(filename, O_RDONLY); 2236 if (fd == -1) { 2237 return false; 2238 } 2239 2240 char buf[32]; 2241 int bytes; 2242 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 2243 st->print_raw(buf, bytes); 2244 } 2245 2246 ::close(fd); 2247 2248 return true; 2249} 2250 2251void os::print_dll_info(outputStream *st) { 2252 st->print_cr("Dynamic libraries:"); 2253#ifdef _ALLBSD_SOURCE 2254#ifdef RTLD_DI_LINKMAP 2255 Dl_info dli; 2256 void *handle; 2257 Link_map *map; 2258 Link_map *p; 2259 2260 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) { 2261 st->print_cr("Error: Cannot print dynamic libraries."); 2262 return; 2263 } 2264 handle = dlopen(dli.dli_fname, RTLD_LAZY); 2265 if (handle == NULL) { 2266 st->print_cr("Error: Cannot print dynamic libraries."); 2267 return; 2268 } 2269 dlinfo(handle, RTLD_DI_LINKMAP, &map); 2270 if (map == NULL) { 2271 st->print_cr("Error: Cannot print dynamic libraries."); 2272 return; 2273 } 2274 2275 while (map->l_prev != NULL) 2276 map = map->l_prev; 2277 2278 while (map != NULL) { 2279 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 2280 map = map->l_next; 2281 } 2282 2283 dlclose(handle); 2284#elif defined(__APPLE__) 2285 uint32_t count; 2286 uint32_t i; 2287 2288 count = _dyld_image_count(); 2289 for (i = 1; i < count; i++) { 2290 const char *name = _dyld_get_image_name(i); 2291 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 2292 st->print_cr(PTR_FORMAT " \t%s", slide, name); 2293 } 2294#else 2295 st->print_cr("Error: Cannot print dynamic libraries."); 2296#endif 2297#else 2298 char fname[32]; 2299 pid_t pid = os::Bsd::gettid(); 2300 2301 jio_snprintf(fname, sizeof(fname), "/proc/%d/maps", pid); 2302 2303 if (!_print_ascii_file(fname, st)) { 2304 st->print("Can not get library information for pid = %d\n", pid); 2305 } 2306#endif 2307} 2308 2309 2310void os::print_os_info(outputStream* st) { 2311 st->print("OS:"); 2312 2313 // Try to identify popular distros. 2314 // Most Bsd distributions have /etc/XXX-release file, which contains 2315 // the OS version string. Some have more than one /etc/XXX-release file 2316 // (e.g. Mandrake has both /etc/mandrake-release and /etc/redhat-release.), 2317 // so the order is important. 2318 if (!_print_ascii_file("/etc/mandrake-release", st) && 2319 !_print_ascii_file("/etc/sun-release", st) && 2320 !_print_ascii_file("/etc/redhat-release", st) && 2321 !_print_ascii_file("/etc/SuSE-release", st) && 2322 !_print_ascii_file("/etc/turbobsd-release", st) && 2323 !_print_ascii_file("/etc/gentoo-release", st) && 2324 !_print_ascii_file("/etc/debian_version", st) && 2325 !_print_ascii_file("/etc/ltib-release", st) && 2326 !_print_ascii_file("/etc/angstrom-version", st)) { 2327 st->print("Bsd"); 2328 } 2329 st->cr(); 2330 2331 // kernel 2332 st->print("uname:"); 2333 struct utsname name; 2334 uname(&name); 2335 st->print(name.sysname); st->print(" "); 2336 st->print(name.release); st->print(" "); 2337 st->print(name.version); st->print(" "); 2338 st->print(name.machine); 2339 st->cr(); 2340 2341#ifndef _ALLBSD_SOURCE 2342 // Print warning if unsafe chroot environment detected 2343 if (unsafe_chroot_detected) { 2344 st->print("WARNING!! "); 2345 st->print_cr(unstable_chroot_error); 2346 } 2347 2348 // libc, pthread 2349 st->print("libc:"); 2350 st->print(os::Bsd::glibc_version()); st->print(" "); 2351 st->print(os::Bsd::libpthread_version()); st->print(" "); 2352 if (os::Bsd::is_BsdThreads()) { 2353 st->print("(%s stack)", os::Bsd::is_floating_stack() ? "floating" : "fixed"); 2354 } 2355 st->cr(); 2356#endif 2357 2358 // rlimit 2359 st->print("rlimit:"); 2360 struct rlimit rlim; 2361 2362 st->print(" STACK "); 2363 getrlimit(RLIMIT_STACK, &rlim); 2364 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2365 else st->print("%uk", rlim.rlim_cur >> 10); 2366 2367 st->print(", CORE "); 2368 getrlimit(RLIMIT_CORE, &rlim); 2369 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2370 else st->print("%uk", rlim.rlim_cur >> 10); 2371 2372 st->print(", NPROC "); 2373 getrlimit(RLIMIT_NPROC, &rlim); 2374 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2375 else st->print("%d", rlim.rlim_cur); 2376 2377 st->print(", NOFILE "); 2378 getrlimit(RLIMIT_NOFILE, &rlim); 2379 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2380 else st->print("%d", rlim.rlim_cur); 2381 2382#ifndef _ALLBSD_SOURCE 2383 st->print(", AS "); 2384 getrlimit(RLIMIT_AS, &rlim); 2385 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2386 else st->print("%uk", rlim.rlim_cur >> 10); 2387 st->cr(); 2388 2389 // load average 2390 st->print("load average:"); 2391 double loadavg[3]; 2392 os::loadavg(loadavg, 3); 2393 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]); 2394 st->cr(); 2395#endif 2396} 2397 2398void os::pd_print_cpu_info(outputStream* st) { 2399 // Nothing to do for now. 2400} 2401 2402void os::print_memory_info(outputStream* st) { 2403 2404 st->print("Memory:"); 2405 st->print(" %dk page", os::vm_page_size()>>10); 2406 2407#ifndef _ALLBSD_SOURCE 2408 // values in struct sysinfo are "unsigned long" 2409 struct sysinfo si; 2410 sysinfo(&si); 2411#endif 2412 2413 st->print(", physical " UINT64_FORMAT "k", 2414 os::physical_memory() >> 10); 2415 st->print("(" UINT64_FORMAT "k free)", 2416 os::available_memory() >> 10); 2417#ifndef _ALLBSD_SOURCE 2418 st->print(", swap " UINT64_FORMAT "k", 2419 ((jlong)si.totalswap * si.mem_unit) >> 10); 2420 st->print("(" UINT64_FORMAT "k free)", 2421 ((jlong)si.freeswap * si.mem_unit) >> 10); 2422#endif 2423 st->cr(); 2424 2425 // meminfo 2426 st->print("\n/proc/meminfo:\n"); 2427 _print_ascii_file("/proc/meminfo", st); 2428 st->cr(); 2429} 2430 2431// Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific 2432// but they're the same for all the bsd arch that we support 2433// and they're the same for solaris but there's no common place to put this. 2434const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR", 2435 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG", 2436 "ILL_COPROC", "ILL_BADSTK" }; 2437 2438const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV", 2439 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES", 2440 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" }; 2441 2442const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" }; 2443 2444const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" }; 2445 2446void os::print_siginfo(outputStream* st, void* siginfo) { 2447 st->print("siginfo:"); 2448 2449 const int buflen = 100; 2450 char buf[buflen]; 2451 siginfo_t *si = (siginfo_t*)siginfo; 2452 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen)); 2453 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) { 2454 st->print("si_errno=%s", buf); 2455 } else { 2456 st->print("si_errno=%d", si->si_errno); 2457 } 2458 const int c = si->si_code; 2459 assert(c > 0, "unexpected si_code"); 2460 switch (si->si_signo) { 2461 case SIGILL: 2462 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]); 2463 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2464 break; 2465 case SIGFPE: 2466 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]); 2467 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2468 break; 2469 case SIGSEGV: 2470 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]); 2471 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2472 break; 2473 case SIGBUS: 2474 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]); 2475 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2476 break; 2477 default: 2478 st->print(", si_code=%d", si->si_code); 2479 // no si_addr 2480 } 2481 2482 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 2483 UseSharedSpaces) { 2484 FileMapInfo* mapinfo = FileMapInfo::current_info(); 2485 if (mapinfo->is_in_shared_space(si->si_addr)) { 2486 st->print("\n\nError accessing class data sharing archive." \ 2487 " Mapped file inaccessible during execution, " \ 2488 " possible disk/network problem."); 2489 } 2490 } 2491 st->cr(); 2492} 2493 2494 2495static void print_signal_handler(outputStream* st, int sig, 2496 char* buf, size_t buflen); 2497 2498void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 2499 st->print_cr("Signal Handlers:"); 2500 print_signal_handler(st, SIGSEGV, buf, buflen); 2501 print_signal_handler(st, SIGBUS , buf, buflen); 2502 print_signal_handler(st, SIGFPE , buf, buflen); 2503 print_signal_handler(st, SIGPIPE, buf, buflen); 2504 print_signal_handler(st, SIGXFSZ, buf, buflen); 2505 print_signal_handler(st, SIGILL , buf, buflen); 2506 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 2507 print_signal_handler(st, SR_signum, buf, buflen); 2508 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 2509 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 2510 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 2511 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 2512} 2513 2514static char saved_jvm_path[MAXPATHLEN] = {0}; 2515 2516// Find the full path to the current module, libjvm or libjvm_g 2517void os::jvm_path(char *buf, jint buflen) { 2518 // Error checking. 2519 if (buflen < MAXPATHLEN) { 2520 assert(false, "must use a large-enough buffer"); 2521 buf[0] = '\0'; 2522 return; 2523 } 2524 // Lazy resolve the path to current module. 2525 if (saved_jvm_path[0] != 0) { 2526 strcpy(buf, saved_jvm_path); 2527 return; 2528 } 2529 2530 char dli_fname[MAXPATHLEN]; 2531 bool ret = dll_address_to_library_name( 2532 CAST_FROM_FN_PTR(address, os::jvm_path), 2533 dli_fname, sizeof(dli_fname), NULL); 2534 assert(ret != 0, "cannot locate libjvm"); 2535 char *rp = realpath(dli_fname, buf); 2536 if (rp == NULL) 2537 return; 2538 2539 if (Arguments::created_by_gamma_launcher()) { 2540 // Support for the gamma launcher. Typical value for buf is 2541 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at 2542 // the right place in the string, then assume we are installed in a JDK and 2543 // we're done. Otherwise, check for a JAVA_HOME environment variable and 2544 // construct a path to the JVM being overridden. 2545 2546 const char *p = buf + strlen(buf) - 1; 2547 for (int count = 0; p > buf && count < 5; ++count) { 2548 for (--p; p > buf && *p != '/'; --p) 2549 /* empty */ ; 2550 } 2551 2552 if (strncmp(p, "/jre/lib/", 9) != 0) { 2553 // Look for JAVA_HOME in the environment. 2554 char* java_home_var = ::getenv("JAVA_HOME"); 2555 if (java_home_var != NULL && java_home_var[0] != 0) { 2556 char* jrelib_p; 2557 int len; 2558 2559 // Check the current module name "libjvm" or "libjvm_g". 2560 p = strrchr(buf, '/'); 2561 assert(strstr(p, "/libjvm") == p, "invalid library name"); 2562 p = strstr(p, "_g") ? "_g" : ""; 2563 2564 rp = realpath(java_home_var, buf); 2565 if (rp == NULL) 2566 return; 2567 2568 // determine if this is a legacy image or modules image 2569 // modules image doesn't have "jre" subdirectory 2570 len = strlen(buf); 2571 jrelib_p = buf + len; 2572 2573 // Add the appropriate library subdir 2574 snprintf(jrelib_p, buflen-len, "/jre/lib"); 2575 if (0 != access(buf, F_OK)) { 2576 snprintf(jrelib_p, buflen-len, "/lib"); 2577 } 2578 2579 // Add the appropriate client or server subdir 2580 len = strlen(buf); 2581 jrelib_p = buf + len; 2582 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 2583 if (0 != access(buf, F_OK)) { 2584 snprintf(jrelib_p, buflen-len, ""); 2585 } 2586 2587 // If the path exists within JAVA_HOME, add the JVM library name 2588 // to complete the path to JVM being overridden. Otherwise fallback 2589 // to the path to the current library. 2590 if (0 == access(buf, F_OK)) { 2591 // Use current module name "libjvm[_g]" instead of 2592 // "libjvm"debug_only("_g")"" since for fastdebug version 2593 // we should have "libjvm" but debug_only("_g") adds "_g"! 2594 len = strlen(buf); 2595 snprintf(buf + len, buflen-len, "/libjvm%s%s", p, JNI_LIB_SUFFIX); 2596 } else { 2597 // Fall back to path of current library 2598 rp = realpath(dli_fname, buf); 2599 if (rp == NULL) 2600 return; 2601 } 2602 } 2603 } 2604 } 2605 2606 strcpy(saved_jvm_path, buf); 2607} 2608 2609void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 2610 // no prefix required, not even "_" 2611} 2612 2613void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 2614 // no suffix required 2615} 2616 2617//////////////////////////////////////////////////////////////////////////////// 2618// sun.misc.Signal support 2619 2620static volatile jint sigint_count = 0; 2621 2622static void 2623UserHandler(int sig, void *siginfo, void *context) { 2624 // 4511530 - sem_post is serialized and handled by the manager thread. When 2625 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 2626 // don't want to flood the manager thread with sem_post requests. 2627 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 2628 return; 2629 2630 // Ctrl-C is pressed during error reporting, likely because the error 2631 // handler fails to abort. Let VM die immediately. 2632 if (sig == SIGINT && is_error_reported()) { 2633 os::die(); 2634 } 2635 2636 os::signal_notify(sig); 2637} 2638 2639void* os::user_handler() { 2640 return CAST_FROM_FN_PTR(void*, UserHandler); 2641} 2642 2643extern "C" { 2644 typedef void (*sa_handler_t)(int); 2645 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 2646} 2647 2648void* os::signal(int signal_number, void* handler) { 2649 struct sigaction sigAct, oldSigAct; 2650 2651 sigfillset(&(sigAct.sa_mask)); 2652 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 2653 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 2654 2655 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 2656 // -1 means registration failed 2657 return (void *)-1; 2658 } 2659 2660 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 2661} 2662 2663void os::signal_raise(int signal_number) { 2664 ::raise(signal_number); 2665} 2666 2667/* 2668 * The following code is moved from os.cpp for making this 2669 * code platform specific, which it is by its very nature. 2670 */ 2671 2672// Will be modified when max signal is changed to be dynamic 2673int os::sigexitnum_pd() { 2674 return NSIG; 2675} 2676 2677// a counter for each possible signal value 2678static volatile jint pending_signals[NSIG+1] = { 0 }; 2679 2680// Bsd(POSIX) specific hand shaking semaphore. 2681#ifdef __APPLE__ 2682static semaphore_t sig_sem; 2683#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 2684#define SEM_WAIT(sem) semaphore_wait(sem); 2685#define SEM_POST(sem) semaphore_signal(sem); 2686#else 2687static sem_t sig_sem; 2688#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 2689#define SEM_WAIT(sem) sem_wait(&sem); 2690#define SEM_POST(sem) sem_post(&sem); 2691#endif 2692 2693void os::signal_init_pd() { 2694 // Initialize signal structures 2695 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2696 2697 // Initialize signal semaphore 2698 ::SEM_INIT(sig_sem, 0); 2699} 2700 2701void os::signal_notify(int sig) { 2702 Atomic::inc(&pending_signals[sig]); 2703 ::SEM_POST(sig_sem); 2704} 2705 2706static int check_pending_signals(bool wait) { 2707 Atomic::store(0, &sigint_count); 2708 for (;;) { 2709 for (int i = 0; i < NSIG + 1; i++) { 2710 jint n = pending_signals[i]; 2711 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2712 return i; 2713 } 2714 } 2715 if (!wait) { 2716 return -1; 2717 } 2718 JavaThread *thread = JavaThread::current(); 2719 ThreadBlockInVM tbivm(thread); 2720 2721 bool threadIsSuspended; 2722 do { 2723 thread->set_suspend_equivalent(); 2724 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2725 ::SEM_WAIT(sig_sem); 2726 2727 // were we externally suspended while we were waiting? 2728 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2729 if (threadIsSuspended) { 2730 // 2731 // The semaphore has been incremented, but while we were waiting 2732 // another thread suspended us. We don't want to continue running 2733 // while suspended because that would surprise the thread that 2734 // suspended us. 2735 // 2736 ::SEM_POST(sig_sem); 2737 2738 thread->java_suspend_self(); 2739 } 2740 } while (threadIsSuspended); 2741 } 2742} 2743 2744int os::signal_lookup() { 2745 return check_pending_signals(false); 2746} 2747 2748int os::signal_wait() { 2749 return check_pending_signals(true); 2750} 2751 2752//////////////////////////////////////////////////////////////////////////////// 2753// Virtual Memory 2754 2755int os::vm_page_size() { 2756 // Seems redundant as all get out 2757 assert(os::Bsd::page_size() != -1, "must call os::init"); 2758 return os::Bsd::page_size(); 2759} 2760 2761// Solaris allocates memory by pages. 2762int os::vm_allocation_granularity() { 2763 assert(os::Bsd::page_size() != -1, "must call os::init"); 2764 return os::Bsd::page_size(); 2765} 2766 2767// Rationale behind this function: 2768// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2769// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2770// samples for JITted code. Here we create private executable mapping over the code cache 2771// and then we can use standard (well, almost, as mapping can change) way to provide 2772// info for the reporting script by storing timestamp and location of symbol 2773void bsd_wrap_code(char* base, size_t size) { 2774 static volatile jint cnt = 0; 2775 2776 if (!UseOprofile) { 2777 return; 2778 } 2779 2780 char buf[PATH_MAX + 1]; 2781 int num = Atomic::add(1, &cnt); 2782 2783 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2784 os::get_temp_directory(), os::current_process_id(), num); 2785 unlink(buf); 2786 2787 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2788 2789 if (fd != -1) { 2790 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2791 if (rv != (off_t)-1) { 2792 if (::write(fd, "", 1) == 1) { 2793 mmap(base, size, 2794 PROT_READ|PROT_WRITE|PROT_EXEC, 2795 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2796 } 2797 } 2798 ::close(fd); 2799 unlink(buf); 2800 } 2801} 2802 2803// NOTE: Bsd kernel does not really reserve the pages for us. 2804// All it does is to check if there are enough free pages 2805// left at the time of mmap(). This could be a potential 2806// problem. 2807bool os::commit_memory(char* addr, size_t size, bool exec) { 2808 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2809#ifdef __OpenBSD__ 2810 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2811 return ::mprotect(addr, size, prot) == 0; 2812#else 2813 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2814 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2815 return res != (uintptr_t) MAP_FAILED; 2816#endif 2817} 2818 2819#ifndef _ALLBSD_SOURCE 2820// Define MAP_HUGETLB here so we can build HotSpot on old systems. 2821#ifndef MAP_HUGETLB 2822#define MAP_HUGETLB 0x40000 2823#endif 2824 2825// Define MADV_HUGEPAGE here so we can build HotSpot on old systems. 2826#ifndef MADV_HUGEPAGE 2827#define MADV_HUGEPAGE 14 2828#endif 2829#endif 2830 2831bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 2832 bool exec) { 2833#ifndef _ALLBSD_SOURCE 2834 if (UseHugeTLBFS && alignment_hint > (size_t)vm_page_size()) { 2835 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2836 uintptr_t res = 2837 (uintptr_t) ::mmap(addr, size, prot, 2838 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS|MAP_HUGETLB, 2839 -1, 0); 2840 return res != (uintptr_t) MAP_FAILED; 2841 } 2842#endif 2843 2844 return commit_memory(addr, size, exec); 2845} 2846 2847void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2848#ifndef _ALLBSD_SOURCE 2849 if (UseHugeTLBFS && alignment_hint > (size_t)vm_page_size()) { 2850 // We don't check the return value: madvise(MADV_HUGEPAGE) may not 2851 // be supported or the memory may already be backed by huge pages. 2852 ::madvise(addr, bytes, MADV_HUGEPAGE); 2853 } 2854#endif 2855} 2856 2857void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2858 ::madvise(addr, bytes, MADV_DONTNEED); 2859} 2860 2861void os::numa_make_global(char *addr, size_t bytes) { 2862} 2863 2864void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2865} 2866 2867bool os::numa_topology_changed() { return false; } 2868 2869size_t os::numa_get_groups_num() { 2870 return 1; 2871} 2872 2873int os::numa_get_group_id() { 2874 return 0; 2875} 2876 2877size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2878 if (size > 0) { 2879 ids[0] = 0; 2880 return 1; 2881 } 2882 return 0; 2883} 2884 2885bool os::get_page_info(char *start, page_info* info) { 2886 return false; 2887} 2888 2889char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2890 return end; 2891} 2892 2893#ifndef _ALLBSD_SOURCE 2894// Something to do with the numa-aware allocator needs these symbols 2895extern "C" JNIEXPORT void numa_warn(int number, char *where, ...) { } 2896extern "C" JNIEXPORT void numa_error(char *where) { } 2897extern "C" JNIEXPORT int fork1() { return fork(); } 2898 2899 2900// If we are running with libnuma version > 2, then we should 2901// be trying to use symbols with versions 1.1 2902// If we are running with earlier version, which did not have symbol versions, 2903// we should use the base version. 2904void* os::Bsd::libnuma_dlsym(void* handle, const char *name) { 2905 void *f = dlvsym(handle, name, "libnuma_1.1"); 2906 if (f == NULL) { 2907 f = dlsym(handle, name); 2908 } 2909 return f; 2910} 2911 2912bool os::Bsd::libnuma_init() { 2913 // sched_getcpu() should be in libc. 2914 set_sched_getcpu(CAST_TO_FN_PTR(sched_getcpu_func_t, 2915 dlsym(RTLD_DEFAULT, "sched_getcpu"))); 2916 2917 if (sched_getcpu() != -1) { // Does it work? 2918 void *handle = dlopen("libnuma.so.1", RTLD_LAZY); 2919 if (handle != NULL) { 2920 set_numa_node_to_cpus(CAST_TO_FN_PTR(numa_node_to_cpus_func_t, 2921 libnuma_dlsym(handle, "numa_node_to_cpus"))); 2922 set_numa_max_node(CAST_TO_FN_PTR(numa_max_node_func_t, 2923 libnuma_dlsym(handle, "numa_max_node"))); 2924 set_numa_available(CAST_TO_FN_PTR(numa_available_func_t, 2925 libnuma_dlsym(handle, "numa_available"))); 2926 set_numa_tonode_memory(CAST_TO_FN_PTR(numa_tonode_memory_func_t, 2927 libnuma_dlsym(handle, "numa_tonode_memory"))); 2928 set_numa_interleave_memory(CAST_TO_FN_PTR(numa_interleave_memory_func_t, 2929 libnuma_dlsym(handle, "numa_interleave_memory"))); 2930 2931 2932 if (numa_available() != -1) { 2933 set_numa_all_nodes((unsigned long*)libnuma_dlsym(handle, "numa_all_nodes")); 2934 // Create a cpu -> node mapping 2935 _cpu_to_node = new (ResourceObj::C_HEAP) GrowableArray<int>(0, true); 2936 rebuild_cpu_to_node_map(); 2937 return true; 2938 } 2939 } 2940 } 2941 return false; 2942} 2943 2944// rebuild_cpu_to_node_map() constructs a table mapping cpud id to node id. 2945// The table is later used in get_node_by_cpu(). 2946void os::Bsd::rebuild_cpu_to_node_map() { 2947 const size_t NCPUS = 32768; // Since the buffer size computation is very obscure 2948 // in libnuma (possible values are starting from 16, 2949 // and continuing up with every other power of 2, but less 2950 // than the maximum number of CPUs supported by kernel), and 2951 // is a subject to change (in libnuma version 2 the requirements 2952 // are more reasonable) we'll just hardcode the number they use 2953 // in the library. 2954 const size_t BitsPerCLong = sizeof(long) * CHAR_BIT; 2955 2956 size_t cpu_num = os::active_processor_count(); 2957 size_t cpu_map_size = NCPUS / BitsPerCLong; 2958 size_t cpu_map_valid_size = 2959 MIN2((cpu_num + BitsPerCLong - 1) / BitsPerCLong, cpu_map_size); 2960 2961 cpu_to_node()->clear(); 2962 cpu_to_node()->at_grow(cpu_num - 1); 2963 size_t node_num = numa_get_groups_num(); 2964 2965 unsigned long *cpu_map = NEW_C_HEAP_ARRAY(unsigned long, cpu_map_size); 2966 for (size_t i = 0; i < node_num; i++) { 2967 if (numa_node_to_cpus(i, cpu_map, cpu_map_size * sizeof(unsigned long)) != -1) { 2968 for (size_t j = 0; j < cpu_map_valid_size; j++) { 2969 if (cpu_map[j] != 0) { 2970 for (size_t k = 0; k < BitsPerCLong; k++) { 2971 if (cpu_map[j] & (1UL << k)) { 2972 cpu_to_node()->at_put(j * BitsPerCLong + k, i); 2973 } 2974 } 2975 } 2976 } 2977 } 2978 } 2979 FREE_C_HEAP_ARRAY(unsigned long, cpu_map); 2980} 2981 2982int os::Bsd::get_node_by_cpu(int cpu_id) { 2983 if (cpu_to_node() != NULL && cpu_id >= 0 && cpu_id < cpu_to_node()->length()) { 2984 return cpu_to_node()->at(cpu_id); 2985 } 2986 return -1; 2987} 2988 2989GrowableArray<int>* os::Bsd::_cpu_to_node; 2990os::Bsd::sched_getcpu_func_t os::Bsd::_sched_getcpu; 2991os::Bsd::numa_node_to_cpus_func_t os::Bsd::_numa_node_to_cpus; 2992os::Bsd::numa_max_node_func_t os::Bsd::_numa_max_node; 2993os::Bsd::numa_available_func_t os::Bsd::_numa_available; 2994os::Bsd::numa_tonode_memory_func_t os::Bsd::_numa_tonode_memory; 2995os::Bsd::numa_interleave_memory_func_t os::Bsd::_numa_interleave_memory; 2996unsigned long* os::Bsd::_numa_all_nodes; 2997#endif 2998 2999bool os::uncommit_memory(char* addr, size_t size) { 3000#ifdef __OpenBSD__ 3001 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 3002 return ::mprotect(addr, size, PROT_NONE) == 0; 3003#else 3004 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 3005 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 3006 return res != (uintptr_t) MAP_FAILED; 3007#endif 3008} 3009 3010bool os::create_stack_guard_pages(char* addr, size_t size) { 3011 return os::commit_memory(addr, size); 3012} 3013 3014// If this is a growable mapping, remove the guard pages entirely by 3015// munmap()ping them. If not, just call uncommit_memory(). 3016bool os::remove_stack_guard_pages(char* addr, size_t size) { 3017 return os::uncommit_memory(addr, size); 3018} 3019 3020static address _highest_vm_reserved_address = NULL; 3021 3022// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 3023// at 'requested_addr'. If there are existing memory mappings at the same 3024// location, however, they will be overwritten. If 'fixed' is false, 3025// 'requested_addr' is only treated as a hint, the return value may or 3026// may not start from the requested address. Unlike Bsd mmap(), this 3027// function returns NULL to indicate failure. 3028static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 3029 char * addr; 3030 int flags; 3031 3032 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 3033 if (fixed) { 3034 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 3035 flags |= MAP_FIXED; 3036 } 3037 3038 // Map uncommitted pages PROT_READ and PROT_WRITE, change access 3039 // to PROT_EXEC if executable when we commit the page. 3040 addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE, 3041 flags, -1, 0); 3042 3043 if (addr != MAP_FAILED) { 3044 // anon_mmap() should only get called during VM initialization, 3045 // don't need lock (actually we can skip locking even it can be called 3046 // from multiple threads, because _highest_vm_reserved_address is just a 3047 // hint about the upper limit of non-stack memory regions.) 3048 if ((address)addr + bytes > _highest_vm_reserved_address) { 3049 _highest_vm_reserved_address = (address)addr + bytes; 3050 } 3051 } 3052 3053 return addr == MAP_FAILED ? NULL : addr; 3054} 3055 3056// Don't update _highest_vm_reserved_address, because there might be memory 3057// regions above addr + size. If so, releasing a memory region only creates 3058// a hole in the address space, it doesn't help prevent heap-stack collision. 3059// 3060static int anon_munmap(char * addr, size_t size) { 3061 return ::munmap(addr, size) == 0; 3062} 3063 3064char* os::reserve_memory(size_t bytes, char* requested_addr, 3065 size_t alignment_hint) { 3066 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 3067} 3068 3069bool os::release_memory(char* addr, size_t size) { 3070 return anon_munmap(addr, size); 3071} 3072 3073static address highest_vm_reserved_address() { 3074 return _highest_vm_reserved_address; 3075} 3076 3077static bool bsd_mprotect(char* addr, size_t size, int prot) { 3078 // Bsd wants the mprotect address argument to be page aligned. 3079 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 3080 3081 // According to SUSv3, mprotect() should only be used with mappings 3082 // established by mmap(), and mmap() always maps whole pages. Unaligned 3083 // 'addr' likely indicates problem in the VM (e.g. trying to change 3084 // protection of malloc'ed or statically allocated memory). Check the 3085 // caller if you hit this assert. 3086 assert(addr == bottom, "sanity check"); 3087 3088 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 3089 return ::mprotect(bottom, size, prot) == 0; 3090} 3091 3092// Set protections specified 3093bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 3094 bool is_committed) { 3095 unsigned int p = 0; 3096 switch (prot) { 3097 case MEM_PROT_NONE: p = PROT_NONE; break; 3098 case MEM_PROT_READ: p = PROT_READ; break; 3099 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 3100 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 3101 default: 3102 ShouldNotReachHere(); 3103 } 3104 // is_committed is unused. 3105 return bsd_mprotect(addr, bytes, p); 3106} 3107 3108bool os::guard_memory(char* addr, size_t size) { 3109 return bsd_mprotect(addr, size, PROT_NONE); 3110} 3111 3112bool os::unguard_memory(char* addr, size_t size) { 3113 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 3114} 3115 3116bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 3117 bool result = false; 3118#ifndef _ALLBSD_SOURCE 3119 void *p = mmap (NULL, page_size, PROT_READ|PROT_WRITE, 3120 MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB, 3121 -1, 0); 3122 3123 if (p != (void *) -1) { 3124 // We don't know if this really is a huge page or not. 3125 FILE *fp = fopen("/proc/self/maps", "r"); 3126 if (fp) { 3127 while (!feof(fp)) { 3128 char chars[257]; 3129 long x = 0; 3130 if (fgets(chars, sizeof(chars), fp)) { 3131 if (sscanf(chars, "%lx-%*x", &x) == 1 3132 && x == (long)p) { 3133 if (strstr (chars, "hugepage")) { 3134 result = true; 3135 break; 3136 } 3137 } 3138 } 3139 } 3140 fclose(fp); 3141 } 3142 munmap (p, page_size); 3143 if (result) 3144 return true; 3145 } 3146 3147 if (warn) { 3148 warning("HugeTLBFS is not supported by the operating system."); 3149 } 3150#endif 3151 3152 return result; 3153} 3154 3155/* 3156* Set the coredump_filter bits to include largepages in core dump (bit 6) 3157* 3158* From the coredump_filter documentation: 3159* 3160* - (bit 0) anonymous private memory 3161* - (bit 1) anonymous shared memory 3162* - (bit 2) file-backed private memory 3163* - (bit 3) file-backed shared memory 3164* - (bit 4) ELF header pages in file-backed private memory areas (it is 3165* effective only if the bit 2 is cleared) 3166* - (bit 5) hugetlb private memory 3167* - (bit 6) hugetlb shared memory 3168*/ 3169static void set_coredump_filter(void) { 3170 FILE *f; 3171 long cdm; 3172 3173 if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) { 3174 return; 3175 } 3176 3177 if (fscanf(f, "%lx", &cdm) != 1) { 3178 fclose(f); 3179 return; 3180 } 3181 3182 rewind(f); 3183 3184 if ((cdm & LARGEPAGES_BIT) == 0) { 3185 cdm |= LARGEPAGES_BIT; 3186 fprintf(f, "%#lx", cdm); 3187 } 3188 3189 fclose(f); 3190} 3191 3192// Large page support 3193 3194static size_t _large_page_size = 0; 3195 3196void os::large_page_init() { 3197#ifndef _ALLBSD_SOURCE 3198 if (!UseLargePages) { 3199 UseHugeTLBFS = false; 3200 UseSHM = false; 3201 return; 3202 } 3203 3204 if (FLAG_IS_DEFAULT(UseHugeTLBFS) && FLAG_IS_DEFAULT(UseSHM)) { 3205 // If UseLargePages is specified on the command line try both methods, 3206 // if it's default, then try only HugeTLBFS. 3207 if (FLAG_IS_DEFAULT(UseLargePages)) { 3208 UseHugeTLBFS = true; 3209 } else { 3210 UseHugeTLBFS = UseSHM = true; 3211 } 3212 } 3213 3214 if (LargePageSizeInBytes) { 3215 _large_page_size = LargePageSizeInBytes; 3216 } else { 3217 // large_page_size on Bsd is used to round up heap size. x86 uses either 3218 // 2M or 4M page, depending on whether PAE (Physical Address Extensions) 3219 // mode is enabled. AMD64/EM64T uses 2M page in 64bit mode. IA64 can use 3220 // page as large as 256M. 3221 // 3222 // Here we try to figure out page size by parsing /proc/meminfo and looking 3223 // for a line with the following format: 3224 // Hugepagesize: 2048 kB 3225 // 3226 // If we can't determine the value (e.g. /proc is not mounted, or the text 3227 // format has been changed), we'll use the largest page size supported by 3228 // the processor. 3229 3230#ifndef ZERO 3231 _large_page_size = IA32_ONLY(4 * M) AMD64_ONLY(2 * M) IA64_ONLY(256 * M) SPARC_ONLY(4 * M) 3232 ARM_ONLY(2 * M) PPC_ONLY(4 * M); 3233#endif // ZERO 3234 3235 FILE *fp = fopen("/proc/meminfo", "r"); 3236 if (fp) { 3237 while (!feof(fp)) { 3238 int x = 0; 3239 char buf[16]; 3240 if (fscanf(fp, "Hugepagesize: %d", &x) == 1) { 3241 if (x && fgets(buf, sizeof(buf), fp) && strcmp(buf, " kB\n") == 0) { 3242 _large_page_size = x * K; 3243 break; 3244 } 3245 } else { 3246 // skip to next line 3247 for (;;) { 3248 int ch = fgetc(fp); 3249 if (ch == EOF || ch == (int)'\n') break; 3250 } 3251 } 3252 } 3253 fclose(fp); 3254 } 3255 } 3256 3257 // print a warning if any large page related flag is specified on command line 3258 bool warn_on_failure = !FLAG_IS_DEFAULT(UseHugeTLBFS); 3259 3260 const size_t default_page_size = (size_t)Bsd::page_size(); 3261 if (_large_page_size > default_page_size) { 3262 _page_sizes[0] = _large_page_size; 3263 _page_sizes[1] = default_page_size; 3264 _page_sizes[2] = 0; 3265 } 3266 UseHugeTLBFS = UseHugeTLBFS && 3267 Bsd::hugetlbfs_sanity_check(warn_on_failure, _large_page_size); 3268 3269 if (UseHugeTLBFS) 3270 UseSHM = false; 3271 3272 UseLargePages = UseHugeTLBFS || UseSHM; 3273 3274 set_coredump_filter(); 3275#endif 3276} 3277 3278#ifndef _ALLBSD_SOURCE 3279#ifndef SHM_HUGETLB 3280#define SHM_HUGETLB 04000 3281#endif 3282#endif 3283 3284char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) { 3285 // "exec" is passed in but not used. Creating the shared image for 3286 // the code cache doesn't have an SHM_X executable permission to check. 3287 assert(UseLargePages && UseSHM, "only for SHM large pages"); 3288 3289 key_t key = IPC_PRIVATE; 3290 char *addr; 3291 3292 bool warn_on_failure = UseLargePages && 3293 (!FLAG_IS_DEFAULT(UseLargePages) || 3294 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 3295 ); 3296 char msg[128]; 3297 3298 // Create a large shared memory region to attach to based on size. 3299 // Currently, size is the total size of the heap 3300#ifndef _ALLBSD_SOURCE 3301 int shmid = shmget(key, bytes, SHM_HUGETLB|IPC_CREAT|SHM_R|SHM_W); 3302#else 3303 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 3304#endif 3305 if (shmid == -1) { 3306 // Possible reasons for shmget failure: 3307 // 1. shmmax is too small for Java heap. 3308 // > check shmmax value: cat /proc/sys/kernel/shmmax 3309 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 3310 // 2. not enough large page memory. 3311 // > check available large pages: cat /proc/meminfo 3312 // > increase amount of large pages: 3313 // echo new_value > /proc/sys/vm/nr_hugepages 3314 // Note 1: different Bsd may use different name for this property, 3315 // e.g. on Redhat AS-3 it is "hugetlb_pool". 3316 // Note 2: it's possible there's enough physical memory available but 3317 // they are so fragmented after a long run that they can't 3318 // coalesce into large pages. Try to reserve large pages when 3319 // the system is still "fresh". 3320 if (warn_on_failure) { 3321 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 3322 warning(msg); 3323 } 3324 return NULL; 3325 } 3326 3327 // attach to the region 3328 addr = (char*)shmat(shmid, req_addr, 0); 3329 int err = errno; 3330 3331 // Remove shmid. If shmat() is successful, the actual shared memory segment 3332 // will be deleted when it's detached by shmdt() or when the process 3333 // terminates. If shmat() is not successful this will remove the shared 3334 // segment immediately. 3335 shmctl(shmid, IPC_RMID, NULL); 3336 3337 if ((intptr_t)addr == -1) { 3338 if (warn_on_failure) { 3339 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 3340 warning(msg); 3341 } 3342 return NULL; 3343 } 3344 3345 return addr; 3346} 3347 3348bool os::release_memory_special(char* base, size_t bytes) { 3349 // detaching the SHM segment will also delete it, see reserve_memory_special() 3350 int rslt = shmdt(base); 3351 return rslt == 0; 3352} 3353 3354size_t os::large_page_size() { 3355 return _large_page_size; 3356} 3357 3358// HugeTLBFS allows application to commit large page memory on demand; 3359// with SysV SHM the entire memory region must be allocated as shared 3360// memory. 3361bool os::can_commit_large_page_memory() { 3362 return UseHugeTLBFS; 3363} 3364 3365bool os::can_execute_large_page_memory() { 3366 return UseHugeTLBFS; 3367} 3368 3369// Reserve memory at an arbitrary address, only if that area is 3370// available (and not reserved for something else). 3371 3372char* os::attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 3373 const int max_tries = 10; 3374 char* base[max_tries]; 3375 size_t size[max_tries]; 3376 const size_t gap = 0x000000; 3377 3378 // Assert only that the size is a multiple of the page size, since 3379 // that's all that mmap requires, and since that's all we really know 3380 // about at this low abstraction level. If we need higher alignment, 3381 // we can either pass an alignment to this method or verify alignment 3382 // in one of the methods further up the call chain. See bug 5044738. 3383 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 3384 3385 // Repeatedly allocate blocks until the block is allocated at the 3386 // right spot. Give up after max_tries. Note that reserve_memory() will 3387 // automatically update _highest_vm_reserved_address if the call is 3388 // successful. The variable tracks the highest memory address every reserved 3389 // by JVM. It is used to detect heap-stack collision if running with 3390 // fixed-stack BsdThreads. Because here we may attempt to reserve more 3391 // space than needed, it could confuse the collision detecting code. To 3392 // solve the problem, save current _highest_vm_reserved_address and 3393 // calculate the correct value before return. 3394 address old_highest = _highest_vm_reserved_address; 3395 3396 // Bsd mmap allows caller to pass an address as hint; give it a try first, 3397 // if kernel honors the hint then we can return immediately. 3398 char * addr = anon_mmap(requested_addr, bytes, false); 3399 if (addr == requested_addr) { 3400 return requested_addr; 3401 } 3402 3403 if (addr != NULL) { 3404 // mmap() is successful but it fails to reserve at the requested address 3405 anon_munmap(addr, bytes); 3406 } 3407 3408 int i; 3409 for (i = 0; i < max_tries; ++i) { 3410 base[i] = reserve_memory(bytes); 3411 3412 if (base[i] != NULL) { 3413 // Is this the block we wanted? 3414 if (base[i] == requested_addr) { 3415 size[i] = bytes; 3416 break; 3417 } 3418 3419 // Does this overlap the block we wanted? Give back the overlapped 3420 // parts and try again. 3421 3422 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 3423 if (top_overlap >= 0 && top_overlap < bytes) { 3424 unmap_memory(base[i], top_overlap); 3425 base[i] += top_overlap; 3426 size[i] = bytes - top_overlap; 3427 } else { 3428 size_t bottom_overlap = base[i] + bytes - requested_addr; 3429 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 3430 unmap_memory(requested_addr, bottom_overlap); 3431 size[i] = bytes - bottom_overlap; 3432 } else { 3433 size[i] = bytes; 3434 } 3435 } 3436 } 3437 } 3438 3439 // Give back the unused reserved pieces. 3440 3441 for (int j = 0; j < i; ++j) { 3442 if (base[j] != NULL) { 3443 unmap_memory(base[j], size[j]); 3444 } 3445 } 3446 3447 if (i < max_tries) { 3448 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 3449 return requested_addr; 3450 } else { 3451 _highest_vm_reserved_address = old_highest; 3452 return NULL; 3453 } 3454} 3455 3456size_t os::read(int fd, void *buf, unsigned int nBytes) { 3457 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 3458} 3459 3460// TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation. 3461// Solaris uses poll(), bsd uses park(). 3462// Poll() is likely a better choice, assuming that Thread.interrupt() 3463// generates a SIGUSRx signal. Note that SIGUSR1 can interfere with 3464// SIGSEGV, see 4355769. 3465 3466int os::sleep(Thread* thread, jlong millis, bool interruptible) { 3467 assert(thread == Thread::current(), "thread consistency check"); 3468 3469 ParkEvent * const slp = thread->_SleepEvent ; 3470 slp->reset() ; 3471 OrderAccess::fence() ; 3472 3473 if (interruptible) { 3474 jlong prevtime = javaTimeNanos(); 3475 3476 for (;;) { 3477 if (os::is_interrupted(thread, true)) { 3478 return OS_INTRPT; 3479 } 3480 3481 jlong newtime = javaTimeNanos(); 3482 3483 if (newtime - prevtime < 0) { 3484 // time moving backwards, should only happen if no monotonic clock 3485 // not a guarantee() because JVM should not abort on kernel/glibc bugs 3486 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 3487 } else { 3488 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 3489 } 3490 3491 if(millis <= 0) { 3492 return OS_OK; 3493 } 3494 3495 prevtime = newtime; 3496 3497 { 3498 assert(thread->is_Java_thread(), "sanity check"); 3499 JavaThread *jt = (JavaThread *) thread; 3500 ThreadBlockInVM tbivm(jt); 3501 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 3502 3503 jt->set_suspend_equivalent(); 3504 // cleared by handle_special_suspend_equivalent_condition() or 3505 // java_suspend_self() via check_and_wait_while_suspended() 3506 3507 slp->park(millis); 3508 3509 // were we externally suspended while we were waiting? 3510 jt->check_and_wait_while_suspended(); 3511 } 3512 } 3513 } else { 3514 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 3515 jlong prevtime = javaTimeNanos(); 3516 3517 for (;;) { 3518 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 3519 // the 1st iteration ... 3520 jlong newtime = javaTimeNanos(); 3521 3522 if (newtime - prevtime < 0) { 3523 // time moving backwards, should only happen if no monotonic clock 3524 // not a guarantee() because JVM should not abort on kernel/glibc bugs 3525 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 3526 } else { 3527 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 3528 } 3529 3530 if(millis <= 0) break ; 3531 3532 prevtime = newtime; 3533 slp->park(millis); 3534 } 3535 return OS_OK ; 3536 } 3537} 3538 3539int os::naked_sleep() { 3540 // %% make the sleep time an integer flag. for now use 1 millisec. 3541 return os::sleep(Thread::current(), 1, false); 3542} 3543 3544// Sleep forever; naked call to OS-specific sleep; use with CAUTION 3545void os::infinite_sleep() { 3546 while (true) { // sleep forever ... 3547 ::sleep(100); // ... 100 seconds at a time 3548 } 3549} 3550 3551// Used to convert frequent JVM_Yield() to nops 3552bool os::dont_yield() { 3553 return DontYieldALot; 3554} 3555 3556void os::yield() { 3557 sched_yield(); 3558} 3559 3560os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 3561 3562void os::yield_all(int attempts) { 3563 // Yields to all threads, including threads with lower priorities 3564 // Threads on Bsd are all with same priority. The Solaris style 3565 // os::yield_all() with nanosleep(1ms) is not necessary. 3566 sched_yield(); 3567} 3568 3569// Called from the tight loops to possibly influence time-sharing heuristics 3570void os::loop_breaker(int attempts) { 3571 os::yield_all(attempts); 3572} 3573 3574//////////////////////////////////////////////////////////////////////////////// 3575// thread priority support 3576 3577// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 3578// only supports dynamic priority, static priority must be zero. For real-time 3579// applications, Bsd supports SCHED_RR which allows static priority (1-99). 3580// However, for large multi-threaded applications, SCHED_RR is not only slower 3581// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 3582// of 5 runs - Sep 2005). 3583// 3584// The following code actually changes the niceness of kernel-thread/LWP. It 3585// has an assumption that setpriority() only modifies one kernel-thread/LWP, 3586// not the entire user process, and user level threads are 1:1 mapped to kernel 3587// threads. It has always been the case, but could change in the future. For 3588// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 3589// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 3590 3591#if defined(_ALLBSD_SOURCE) && !defined(__APPLE__) 3592int os::java_to_os_priority[MaxPriority + 1] = { 3593 19, // 0 Entry should never be used 3594 3595 0, // 1 MinPriority 3596 3, // 2 3597 6, // 3 3598 3599 10, // 4 3600 15, // 5 NormPriority 3601 18, // 6 3602 3603 21, // 7 3604 25, // 8 3605 28, // 9 NearMaxPriority 3606 3607 31 // 10 MaxPriority 3608}; 3609#elif defined(__APPLE__) 3610/* Using Mach high-level priority assignments */ 3611int os::java_to_os_priority[MaxPriority + 1] = { 3612 0, // 0 Entry should never be used (MINPRI_USER) 3613 3614 27, // 1 MinPriority 3615 28, // 2 3616 29, // 3 3617 3618 30, // 4 3619 31, // 5 NormPriority (BASEPRI_DEFAULT) 3620 32, // 6 3621 3622 33, // 7 3623 34, // 8 3624 35, // 9 NearMaxPriority 3625 3626 36 // 10 MaxPriority 3627}; 3628#else 3629int os::java_to_os_priority[MaxPriority + 1] = { 3630 19, // 0 Entry should never be used 3631 3632 4, // 1 MinPriority 3633 3, // 2 3634 2, // 3 3635 3636 1, // 4 3637 0, // 5 NormPriority 3638 -1, // 6 3639 3640 -2, // 7 3641 -3, // 8 3642 -4, // 9 NearMaxPriority 3643 3644 -5 // 10 MaxPriority 3645}; 3646#endif 3647 3648static int prio_init() { 3649 if (ThreadPriorityPolicy == 1) { 3650 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 3651 // if effective uid is not root. Perhaps, a more elegant way of doing 3652 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 3653 if (geteuid() != 0) { 3654 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 3655 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 3656 } 3657 ThreadPriorityPolicy = 0; 3658 } 3659 } 3660 return 0; 3661} 3662 3663OSReturn os::set_native_priority(Thread* thread, int newpri) { 3664 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 3665 3666#ifdef __OpenBSD__ 3667 // OpenBSD pthread_setprio starves low priority threads 3668 return OS_OK; 3669#elif defined(__FreeBSD__) 3670 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 3671#elif defined(__APPLE__) || defined(__NetBSD__) 3672 struct sched_param sp; 3673 int policy; 3674 pthread_t self = pthread_self(); 3675 3676 if (pthread_getschedparam(self, &policy, &sp) != 0) 3677 return OS_ERR; 3678 3679 sp.sched_priority = newpri; 3680 if (pthread_setschedparam(self, policy, &sp) != 0) 3681 return OS_ERR; 3682 3683 return OS_OK; 3684#else 3685 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 3686 return (ret == 0) ? OS_OK : OS_ERR; 3687#endif 3688} 3689 3690OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 3691 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 3692 *priority_ptr = java_to_os_priority[NormPriority]; 3693 return OS_OK; 3694 } 3695 3696 errno = 0; 3697#if defined(__OpenBSD__) || defined(__FreeBSD__) 3698 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 3699#elif defined(__APPLE__) || defined(__NetBSD__) 3700 int policy; 3701 struct sched_param sp; 3702 3703 pthread_getschedparam(pthread_self(), &policy, &sp); 3704 *priority_ptr = sp.sched_priority; 3705#else 3706 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 3707#endif 3708 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 3709} 3710 3711// Hint to the underlying OS that a task switch would not be good. 3712// Void return because it's a hint and can fail. 3713void os::hint_no_preempt() {} 3714 3715//////////////////////////////////////////////////////////////////////////////// 3716// suspend/resume support 3717 3718// the low-level signal-based suspend/resume support is a remnant from the 3719// old VM-suspension that used to be for java-suspension, safepoints etc, 3720// within hotspot. Now there is a single use-case for this: 3721// - calling get_thread_pc() on the VMThread by the flat-profiler task 3722// that runs in the watcher thread. 3723// The remaining code is greatly simplified from the more general suspension 3724// code that used to be used. 3725// 3726// The protocol is quite simple: 3727// - suspend: 3728// - sends a signal to the target thread 3729// - polls the suspend state of the osthread using a yield loop 3730// - target thread signal handler (SR_handler) sets suspend state 3731// and blocks in sigsuspend until continued 3732// - resume: 3733// - sets target osthread state to continue 3734// - sends signal to end the sigsuspend loop in the SR_handler 3735// 3736// Note that the SR_lock plays no role in this suspend/resume protocol. 3737// 3738 3739static void resume_clear_context(OSThread *osthread) { 3740 osthread->set_ucontext(NULL); 3741 osthread->set_siginfo(NULL); 3742 3743 // notify the suspend action is completed, we have now resumed 3744 osthread->sr.clear_suspended(); 3745} 3746 3747static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 3748 osthread->set_ucontext(context); 3749 osthread->set_siginfo(siginfo); 3750} 3751 3752// 3753// Handler function invoked when a thread's execution is suspended or 3754// resumed. We have to be careful that only async-safe functions are 3755// called here (Note: most pthread functions are not async safe and 3756// should be avoided.) 3757// 3758// Note: sigwait() is a more natural fit than sigsuspend() from an 3759// interface point of view, but sigwait() prevents the signal hander 3760// from being run. libpthread would get very confused by not having 3761// its signal handlers run and prevents sigwait()'s use with the 3762// mutex granting granting signal. 3763// 3764// Currently only ever called on the VMThread 3765// 3766static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 3767 // Save and restore errno to avoid confusing native code with EINTR 3768 // after sigsuspend. 3769 int old_errno = errno; 3770 3771 Thread* thread = Thread::current(); 3772 OSThread* osthread = thread->osthread(); 3773 assert(thread->is_VM_thread(), "Must be VMThread"); 3774 // read current suspend action 3775 int action = osthread->sr.suspend_action(); 3776 if (action == SR_SUSPEND) { 3777 suspend_save_context(osthread, siginfo, context); 3778 3779 // Notify the suspend action is about to be completed. do_suspend() 3780 // waits until SR_SUSPENDED is set and then returns. We will wait 3781 // here for a resume signal and that completes the suspend-other 3782 // action. do_suspend/do_resume is always called as a pair from 3783 // the same thread - so there are no races 3784 3785 // notify the caller 3786 osthread->sr.set_suspended(); 3787 3788 sigset_t suspend_set; // signals for sigsuspend() 3789 3790 // get current set of blocked signals and unblock resume signal 3791 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 3792 sigdelset(&suspend_set, SR_signum); 3793 3794 // wait here until we are resumed 3795 do { 3796 sigsuspend(&suspend_set); 3797 // ignore all returns until we get a resume signal 3798 } while (osthread->sr.suspend_action() != SR_CONTINUE); 3799 3800 resume_clear_context(osthread); 3801 3802 } else { 3803 assert(action == SR_CONTINUE, "unexpected sr action"); 3804 // nothing special to do - just leave the handler 3805 } 3806 3807 errno = old_errno; 3808} 3809 3810 3811static int SR_initialize() { 3812 struct sigaction act; 3813 char *s; 3814 /* Get signal number to use for suspend/resume */ 3815 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 3816 int sig = ::strtol(s, 0, 10); 3817 if (sig > 0 || sig < NSIG) { 3818 SR_signum = sig; 3819 } 3820 } 3821 3822 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 3823 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 3824 3825 sigemptyset(&SR_sigset); 3826 sigaddset(&SR_sigset, SR_signum); 3827 3828 /* Set up signal handler for suspend/resume */ 3829 act.sa_flags = SA_RESTART|SA_SIGINFO; 3830 act.sa_handler = (void (*)(int)) SR_handler; 3831 3832 // SR_signum is blocked by default. 3833 // 4528190 - We also need to block pthread restart signal (32 on all 3834 // supported Bsd platforms). Note that BsdThreads need to block 3835 // this signal for all threads to work properly. So we don't have 3836 // to use hard-coded signal number when setting up the mask. 3837 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 3838 3839 if (sigaction(SR_signum, &act, 0) == -1) { 3840 return -1; 3841 } 3842 3843 // Save signal flag 3844 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 3845 return 0; 3846} 3847 3848static int SR_finalize() { 3849 return 0; 3850} 3851 3852 3853// returns true on success and false on error - really an error is fatal 3854// but this seems the normal response to library errors 3855static bool do_suspend(OSThread* osthread) { 3856 // mark as suspended and send signal 3857 osthread->sr.set_suspend_action(SR_SUSPEND); 3858 int status = pthread_kill(osthread->pthread_id(), SR_signum); 3859 assert_status(status == 0, status, "pthread_kill"); 3860 3861 // check status and wait until notified of suspension 3862 if (status == 0) { 3863 for (int i = 0; !osthread->sr.is_suspended(); i++) { 3864 os::yield_all(i); 3865 } 3866 osthread->sr.set_suspend_action(SR_NONE); 3867 return true; 3868 } 3869 else { 3870 osthread->sr.set_suspend_action(SR_NONE); 3871 return false; 3872 } 3873} 3874 3875static void do_resume(OSThread* osthread) { 3876 assert(osthread->sr.is_suspended(), "thread should be suspended"); 3877 osthread->sr.set_suspend_action(SR_CONTINUE); 3878 3879 int status = pthread_kill(osthread->pthread_id(), SR_signum); 3880 assert_status(status == 0, status, "pthread_kill"); 3881 // check status and wait unit notified of resumption 3882 if (status == 0) { 3883 for (int i = 0; osthread->sr.is_suspended(); i++) { 3884 os::yield_all(i); 3885 } 3886 } 3887 osthread->sr.set_suspend_action(SR_NONE); 3888} 3889 3890//////////////////////////////////////////////////////////////////////////////// 3891// interrupt support 3892 3893void os::interrupt(Thread* thread) { 3894 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3895 "possibility of dangling Thread pointer"); 3896 3897 OSThread* osthread = thread->osthread(); 3898 3899 if (!osthread->interrupted()) { 3900 osthread->set_interrupted(true); 3901 // More than one thread can get here with the same value of osthread, 3902 // resulting in multiple notifications. We do, however, want the store 3903 // to interrupted() to be visible to other threads before we execute unpark(). 3904 OrderAccess::fence(); 3905 ParkEvent * const slp = thread->_SleepEvent ; 3906 if (slp != NULL) slp->unpark() ; 3907 } 3908 3909 // For JSR166. Unpark even if interrupt status already was set 3910 if (thread->is_Java_thread()) 3911 ((JavaThread*)thread)->parker()->unpark(); 3912 3913 ParkEvent * ev = thread->_ParkEvent ; 3914 if (ev != NULL) ev->unpark() ; 3915 3916} 3917 3918bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 3919 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3920 "possibility of dangling Thread pointer"); 3921 3922 OSThread* osthread = thread->osthread(); 3923 3924 bool interrupted = osthread->interrupted(); 3925 3926 if (interrupted && clear_interrupted) { 3927 osthread->set_interrupted(false); 3928 // consider thread->_SleepEvent->reset() ... optional optimization 3929 } 3930 3931 return interrupted; 3932} 3933 3934/////////////////////////////////////////////////////////////////////////////////// 3935// signal handling (except suspend/resume) 3936 3937// This routine may be used by user applications as a "hook" to catch signals. 3938// The user-defined signal handler must pass unrecognized signals to this 3939// routine, and if it returns true (non-zero), then the signal handler must 3940// return immediately. If the flag "abort_if_unrecognized" is true, then this 3941// routine will never retun false (zero), but instead will execute a VM panic 3942// routine kill the process. 3943// 3944// If this routine returns false, it is OK to call it again. This allows 3945// the user-defined signal handler to perform checks either before or after 3946// the VM performs its own checks. Naturally, the user code would be making 3947// a serious error if it tried to handle an exception (such as a null check 3948// or breakpoint) that the VM was generating for its own correct operation. 3949// 3950// This routine may recognize any of the following kinds of signals: 3951// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 3952// It should be consulted by handlers for any of those signals. 3953// 3954// The caller of this routine must pass in the three arguments supplied 3955// to the function referred to in the "sa_sigaction" (not the "sa_handler") 3956// field of the structure passed to sigaction(). This routine assumes that 3957// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 3958// 3959// Note that the VM will print warnings if it detects conflicting signal 3960// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 3961// 3962extern "C" JNIEXPORT int 3963JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 3964 void* ucontext, int abort_if_unrecognized); 3965 3966void signalHandler(int sig, siginfo_t* info, void* uc) { 3967 assert(info != NULL && uc != NULL, "it must be old kernel"); 3968 JVM_handle_bsd_signal(sig, info, uc, true); 3969} 3970 3971 3972// This boolean allows users to forward their own non-matching signals 3973// to JVM_handle_bsd_signal, harmlessly. 3974bool os::Bsd::signal_handlers_are_installed = false; 3975 3976// For signal-chaining 3977struct sigaction os::Bsd::sigact[MAXSIGNUM]; 3978unsigned int os::Bsd::sigs = 0; 3979bool os::Bsd::libjsig_is_loaded = false; 3980typedef struct sigaction *(*get_signal_t)(int); 3981get_signal_t os::Bsd::get_signal_action = NULL; 3982 3983struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 3984 struct sigaction *actp = NULL; 3985 3986 if (libjsig_is_loaded) { 3987 // Retrieve the old signal handler from libjsig 3988 actp = (*get_signal_action)(sig); 3989 } 3990 if (actp == NULL) { 3991 // Retrieve the preinstalled signal handler from jvm 3992 actp = get_preinstalled_handler(sig); 3993 } 3994 3995 return actp; 3996} 3997 3998static bool call_chained_handler(struct sigaction *actp, int sig, 3999 siginfo_t *siginfo, void *context) { 4000 // Call the old signal handler 4001 if (actp->sa_handler == SIG_DFL) { 4002 // It's more reasonable to let jvm treat it as an unexpected exception 4003 // instead of taking the default action. 4004 return false; 4005 } else if (actp->sa_handler != SIG_IGN) { 4006 if ((actp->sa_flags & SA_NODEFER) == 0) { 4007 // automaticlly block the signal 4008 sigaddset(&(actp->sa_mask), sig); 4009 } 4010 4011 sa_handler_t hand; 4012 sa_sigaction_t sa; 4013 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 4014 // retrieve the chained handler 4015 if (siginfo_flag_set) { 4016 sa = actp->sa_sigaction; 4017 } else { 4018 hand = actp->sa_handler; 4019 } 4020 4021 if ((actp->sa_flags & SA_RESETHAND) != 0) { 4022 actp->sa_handler = SIG_DFL; 4023 } 4024 4025 // try to honor the signal mask 4026 sigset_t oset; 4027 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 4028 4029 // call into the chained handler 4030 if (siginfo_flag_set) { 4031 (*sa)(sig, siginfo, context); 4032 } else { 4033 (*hand)(sig); 4034 } 4035 4036 // restore the signal mask 4037 pthread_sigmask(SIG_SETMASK, &oset, 0); 4038 } 4039 // Tell jvm's signal handler the signal is taken care of. 4040 return true; 4041} 4042 4043bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 4044 bool chained = false; 4045 // signal-chaining 4046 if (UseSignalChaining) { 4047 struct sigaction *actp = get_chained_signal_action(sig); 4048 if (actp != NULL) { 4049 chained = call_chained_handler(actp, sig, siginfo, context); 4050 } 4051 } 4052 return chained; 4053} 4054 4055struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 4056 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 4057 return &sigact[sig]; 4058 } 4059 return NULL; 4060} 4061 4062void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 4063 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4064 sigact[sig] = oldAct; 4065 sigs |= (unsigned int)1 << sig; 4066} 4067 4068// for diagnostic 4069int os::Bsd::sigflags[MAXSIGNUM]; 4070 4071int os::Bsd::get_our_sigflags(int sig) { 4072 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4073 return sigflags[sig]; 4074} 4075 4076void os::Bsd::set_our_sigflags(int sig, int flags) { 4077 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4078 sigflags[sig] = flags; 4079} 4080 4081void os::Bsd::set_signal_handler(int sig, bool set_installed) { 4082 // Check for overwrite. 4083 struct sigaction oldAct; 4084 sigaction(sig, (struct sigaction*)NULL, &oldAct); 4085 4086 void* oldhand = oldAct.sa_sigaction 4087 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 4088 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 4089 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 4090 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 4091 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 4092 if (AllowUserSignalHandlers || !set_installed) { 4093 // Do not overwrite; user takes responsibility to forward to us. 4094 return; 4095 } else if (UseSignalChaining) { 4096 // save the old handler in jvm 4097 save_preinstalled_handler(sig, oldAct); 4098 // libjsig also interposes the sigaction() call below and saves the 4099 // old sigaction on it own. 4100 } else { 4101 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 4102 "%#lx for signal %d.", (long)oldhand, sig)); 4103 } 4104 } 4105 4106 struct sigaction sigAct; 4107 sigfillset(&(sigAct.sa_mask)); 4108 sigAct.sa_handler = SIG_DFL; 4109 if (!set_installed) { 4110 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 4111 } else { 4112 sigAct.sa_sigaction = signalHandler; 4113 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 4114 } 4115 // Save flags, which are set by ours 4116 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4117 sigflags[sig] = sigAct.sa_flags; 4118 4119 int ret = sigaction(sig, &sigAct, &oldAct); 4120 assert(ret == 0, "check"); 4121 4122 void* oldhand2 = oldAct.sa_sigaction 4123 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 4124 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 4125 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 4126} 4127 4128// install signal handlers for signals that HotSpot needs to 4129// handle in order to support Java-level exception handling. 4130 4131void os::Bsd::install_signal_handlers() { 4132 if (!signal_handlers_are_installed) { 4133 signal_handlers_are_installed = true; 4134 4135 // signal-chaining 4136 typedef void (*signal_setting_t)(); 4137 signal_setting_t begin_signal_setting = NULL; 4138 signal_setting_t end_signal_setting = NULL; 4139 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 4140 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 4141 if (begin_signal_setting != NULL) { 4142 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 4143 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 4144 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 4145 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 4146 libjsig_is_loaded = true; 4147 assert(UseSignalChaining, "should enable signal-chaining"); 4148 } 4149 if (libjsig_is_loaded) { 4150 // Tell libjsig jvm is setting signal handlers 4151 (*begin_signal_setting)(); 4152 } 4153 4154 set_signal_handler(SIGSEGV, true); 4155 set_signal_handler(SIGPIPE, true); 4156 set_signal_handler(SIGBUS, true); 4157 set_signal_handler(SIGILL, true); 4158 set_signal_handler(SIGFPE, true); 4159 set_signal_handler(SIGXFSZ, true); 4160 4161#if defined(__APPLE__) 4162 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 4163 // signals caught and handled by the JVM. To work around this, we reset the mach task 4164 // signal handler that's placed on our process by CrashReporter. This disables 4165 // CrashReporter-based reporting. 4166 // 4167 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 4168 // on caught fatal signals. 4169 // 4170 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 4171 // handlers. By replacing the existing task exception handler, we disable gdb's mach 4172 // exception handling, while leaving the standard BSD signal handlers functional. 4173 kern_return_t kr; 4174 kr = task_set_exception_ports(mach_task_self(), 4175 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 4176 MACH_PORT_NULL, 4177 EXCEPTION_STATE_IDENTITY, 4178 MACHINE_THREAD_STATE); 4179 4180 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 4181#endif 4182 4183 if (libjsig_is_loaded) { 4184 // Tell libjsig jvm finishes setting signal handlers 4185 (*end_signal_setting)(); 4186 } 4187 4188 // We don't activate signal checker if libjsig is in place, we trust ourselves 4189 // and if UserSignalHandler is installed all bets are off 4190 if (CheckJNICalls) { 4191 if (libjsig_is_loaded) { 4192 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 4193 check_signals = false; 4194 } 4195 if (AllowUserSignalHandlers) { 4196 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 4197 check_signals = false; 4198 } 4199 } 4200 } 4201} 4202 4203#ifndef _ALLBSD_SOURCE 4204// This is the fastest way to get thread cpu time on Bsd. 4205// Returns cpu time (user+sys) for any thread, not only for current. 4206// POSIX compliant clocks are implemented in the kernels 2.6.16+. 4207// It might work on 2.6.10+ with a special kernel/glibc patch. 4208// For reference, please, see IEEE Std 1003.1-2004: 4209// http://www.unix.org/single_unix_specification 4210 4211jlong os::Bsd::fast_thread_cpu_time(clockid_t clockid) { 4212 struct timespec tp; 4213 int rc = os::Bsd::clock_gettime(clockid, &tp); 4214 assert(rc == 0, "clock_gettime is expected to return 0 code"); 4215 4216 return (tp.tv_sec * NANOSECS_PER_SEC) + tp.tv_nsec; 4217} 4218#endif 4219 4220///// 4221// glibc on Bsd platform uses non-documented flag 4222// to indicate, that some special sort of signal 4223// trampoline is used. 4224// We will never set this flag, and we should 4225// ignore this flag in our diagnostic 4226#ifdef SIGNIFICANT_SIGNAL_MASK 4227#undef SIGNIFICANT_SIGNAL_MASK 4228#endif 4229#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 4230 4231static const char* get_signal_handler_name(address handler, 4232 char* buf, int buflen) { 4233 int offset; 4234 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 4235 if (found) { 4236 // skip directory names 4237 const char *p1, *p2; 4238 p1 = buf; 4239 size_t len = strlen(os::file_separator()); 4240 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 4241 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 4242 } else { 4243 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 4244 } 4245 return buf; 4246} 4247 4248static void print_signal_handler(outputStream* st, int sig, 4249 char* buf, size_t buflen) { 4250 struct sigaction sa; 4251 4252 sigaction(sig, NULL, &sa); 4253 4254 // See comment for SIGNIFICANT_SIGNAL_MASK define 4255 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 4256 4257 st->print("%s: ", os::exception_name(sig, buf, buflen)); 4258 4259 address handler = (sa.sa_flags & SA_SIGINFO) 4260 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 4261 : CAST_FROM_FN_PTR(address, sa.sa_handler); 4262 4263 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 4264 st->print("SIG_DFL"); 4265 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 4266 st->print("SIG_IGN"); 4267 } else { 4268 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 4269 } 4270 4271 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask); 4272 4273 address rh = VMError::get_resetted_sighandler(sig); 4274 // May be, handler was resetted by VMError? 4275 if(rh != NULL) { 4276 handler = rh; 4277 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 4278 } 4279 4280 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags); 4281 4282 // Check: is it our handler? 4283 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 4284 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 4285 // It is our signal handler 4286 // check for flags, reset system-used one! 4287 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 4288 st->print( 4289 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 4290 os::Bsd::get_our_sigflags(sig)); 4291 } 4292 } 4293 st->cr(); 4294} 4295 4296 4297#define DO_SIGNAL_CHECK(sig) \ 4298 if (!sigismember(&check_signal_done, sig)) \ 4299 os::Bsd::check_signal_handler(sig) 4300 4301// This method is a periodic task to check for misbehaving JNI applications 4302// under CheckJNI, we can add any periodic checks here 4303 4304void os::run_periodic_checks() { 4305 4306 if (check_signals == false) return; 4307 4308 // SEGV and BUS if overridden could potentially prevent 4309 // generation of hs*.log in the event of a crash, debugging 4310 // such a case can be very challenging, so we absolutely 4311 // check the following for a good measure: 4312 DO_SIGNAL_CHECK(SIGSEGV); 4313 DO_SIGNAL_CHECK(SIGILL); 4314 DO_SIGNAL_CHECK(SIGFPE); 4315 DO_SIGNAL_CHECK(SIGBUS); 4316 DO_SIGNAL_CHECK(SIGPIPE); 4317 DO_SIGNAL_CHECK(SIGXFSZ); 4318 4319 4320 // ReduceSignalUsage allows the user to override these handlers 4321 // see comments at the very top and jvm_solaris.h 4322 if (!ReduceSignalUsage) { 4323 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 4324 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 4325 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 4326 DO_SIGNAL_CHECK(BREAK_SIGNAL); 4327 } 4328 4329 DO_SIGNAL_CHECK(SR_signum); 4330 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 4331} 4332 4333typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 4334 4335static os_sigaction_t os_sigaction = NULL; 4336 4337void os::Bsd::check_signal_handler(int sig) { 4338 char buf[O_BUFLEN]; 4339 address jvmHandler = NULL; 4340 4341 4342 struct sigaction act; 4343 if (os_sigaction == NULL) { 4344 // only trust the default sigaction, in case it has been interposed 4345 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 4346 if (os_sigaction == NULL) return; 4347 } 4348 4349 os_sigaction(sig, (struct sigaction*)NULL, &act); 4350 4351 4352 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 4353 4354 address thisHandler = (act.sa_flags & SA_SIGINFO) 4355 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 4356 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 4357 4358 4359 switch(sig) { 4360 case SIGSEGV: 4361 case SIGBUS: 4362 case SIGFPE: 4363 case SIGPIPE: 4364 case SIGILL: 4365 case SIGXFSZ: 4366 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 4367 break; 4368 4369 case SHUTDOWN1_SIGNAL: 4370 case SHUTDOWN2_SIGNAL: 4371 case SHUTDOWN3_SIGNAL: 4372 case BREAK_SIGNAL: 4373 jvmHandler = (address)user_handler(); 4374 break; 4375 4376 case INTERRUPT_SIGNAL: 4377 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 4378 break; 4379 4380 default: 4381 if (sig == SR_signum) { 4382 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 4383 } else { 4384 return; 4385 } 4386 break; 4387 } 4388 4389 if (thisHandler != jvmHandler) { 4390 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 4391 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 4392 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 4393 // No need to check this sig any longer 4394 sigaddset(&check_signal_done, sig); 4395 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 4396 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 4397 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 4398 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 4399 // No need to check this sig any longer 4400 sigaddset(&check_signal_done, sig); 4401 } 4402 4403 // Dump all the signal 4404 if (sigismember(&check_signal_done, sig)) { 4405 print_signal_handlers(tty, buf, O_BUFLEN); 4406 } 4407} 4408 4409extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 4410 4411extern bool signal_name(int signo, char* buf, size_t len); 4412 4413const char* os::exception_name(int exception_code, char* buf, size_t size) { 4414 if (0 < exception_code && exception_code <= SIGRTMAX) { 4415 // signal 4416 if (!signal_name(exception_code, buf, size)) { 4417 jio_snprintf(buf, size, "SIG%d", exception_code); 4418 } 4419 return buf; 4420 } else { 4421 return NULL; 4422 } 4423} 4424 4425// this is called _before_ the most of global arguments have been parsed 4426void os::init(void) { 4427 char dummy; /* used to get a guess on initial stack address */ 4428// first_hrtime = gethrtime(); 4429 4430 // With BsdThreads the JavaMain thread pid (primordial thread) 4431 // is different than the pid of the java launcher thread. 4432 // So, on Bsd, the launcher thread pid is passed to the VM 4433 // via the sun.java.launcher.pid property. 4434 // Use this property instead of getpid() if it was correctly passed. 4435 // See bug 6351349. 4436 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 4437 4438 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 4439 4440 clock_tics_per_sec = CLK_TCK; 4441 4442 init_random(1234567); 4443 4444 ThreadCritical::initialize(); 4445 4446 Bsd::set_page_size(getpagesize()); 4447 if (Bsd::page_size() == -1) { 4448 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 4449 strerror(errno))); 4450 } 4451 init_page_sizes((size_t) Bsd::page_size()); 4452 4453 Bsd::initialize_system_info(); 4454 4455 // main_thread points to the aboriginal thread 4456 Bsd::_main_thread = pthread_self(); 4457 4458 Bsd::clock_init(); 4459 initial_time_count = os::elapsed_counter(); 4460 4461#ifdef __APPLE__ 4462 // XXXDARWIN 4463 // Work around the unaligned VM callbacks in hotspot's 4464 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 4465 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 4466 // alignment when doing symbol lookup. To work around this, we force early 4467 // binding of all symbols now, thus binding when alignment is known-good. 4468 _dyld_bind_fully_image_containing_address((const void *) &os::init); 4469#endif 4470} 4471 4472// To install functions for atexit system call 4473extern "C" { 4474 static void perfMemory_exit_helper() { 4475 perfMemory_exit(); 4476 } 4477} 4478 4479// this is called _after_ the global arguments have been parsed 4480jint os::init_2(void) 4481{ 4482#ifndef _ALLBSD_SOURCE 4483 Bsd::fast_thread_clock_init(); 4484#endif 4485 4486 // Allocate a single page and mark it as readable for safepoint polling 4487 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 4488 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 4489 4490 os::set_polling_page( polling_page ); 4491 4492#ifndef PRODUCT 4493 if(Verbose && PrintMiscellaneous) 4494 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 4495#endif 4496 4497 if (!UseMembar) { 4498 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 4499 guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page"); 4500 os::set_memory_serialize_page( mem_serialize_page ); 4501 4502#ifndef PRODUCT 4503 if(Verbose && PrintMiscellaneous) 4504 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 4505#endif 4506 } 4507 4508 os::large_page_init(); 4509 4510 // initialize suspend/resume support - must do this before signal_sets_init() 4511 if (SR_initialize() != 0) { 4512 perror("SR_initialize failed"); 4513 return JNI_ERR; 4514 } 4515 4516 Bsd::signal_sets_init(); 4517 Bsd::install_signal_handlers(); 4518 4519 // Check minimum allowable stack size for thread creation and to initialize 4520 // the java system classes, including StackOverflowError - depends on page 4521 // size. Add a page for compiler2 recursion in main thread. 4522 // Add in 2*BytesPerWord times page size to account for VM stack during 4523 // class initialization depending on 32 or 64 bit VM. 4524 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 4525 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 4526 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 4527 4528 size_t threadStackSizeInBytes = ThreadStackSize * K; 4529 if (threadStackSizeInBytes != 0 && 4530 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 4531 tty->print_cr("\nThe stack size specified is too small, " 4532 "Specify at least %dk", 4533 os::Bsd::min_stack_allowed/ K); 4534 return JNI_ERR; 4535 } 4536 4537 // Make the stack size a multiple of the page size so that 4538 // the yellow/red zones can be guarded. 4539 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 4540 vm_page_size())); 4541 4542#ifndef _ALLBSD_SOURCE 4543 Bsd::capture_initial_stack(JavaThread::stack_size_at_create()); 4544 4545 Bsd::libpthread_init(); 4546 if (PrintMiscellaneous && (Verbose || WizardMode)) { 4547 tty->print_cr("[HotSpot is running with %s, %s(%s)]\n", 4548 Bsd::glibc_version(), Bsd::libpthread_version(), 4549 Bsd::is_floating_stack() ? "floating stack" : "fixed stack"); 4550 } 4551 4552 if (UseNUMA) { 4553 if (!Bsd::libnuma_init()) { 4554 UseNUMA = false; 4555 } else { 4556 if ((Bsd::numa_max_node() < 1)) { 4557 // There's only one node(they start from 0), disable NUMA. 4558 UseNUMA = false; 4559 } 4560 } 4561 // With SHM large pages we cannot uncommit a page, so there's not way 4562 // we can make the adaptive lgrp chunk resizing work. If the user specified 4563 // both UseNUMA and UseLargePages (or UseSHM) on the command line - warn and 4564 // disable adaptive resizing. 4565 if (UseNUMA && UseLargePages && UseSHM) { 4566 if (!FLAG_IS_DEFAULT(UseNUMA)) { 4567 if (FLAG_IS_DEFAULT(UseLargePages) && FLAG_IS_DEFAULT(UseSHM)) { 4568 UseLargePages = false; 4569 } else { 4570 warning("UseNUMA is not fully compatible with SHM large pages, disabling adaptive resizing"); 4571 UseAdaptiveSizePolicy = false; 4572 UseAdaptiveNUMAChunkSizing = false; 4573 } 4574 } else { 4575 UseNUMA = false; 4576 } 4577 } 4578 if (!UseNUMA && ForceNUMA) { 4579 UseNUMA = true; 4580 } 4581 } 4582#endif 4583 4584 if (MaxFDLimit) { 4585 // set the number of file descriptors to max. print out error 4586 // if getrlimit/setrlimit fails but continue regardless. 4587 struct rlimit nbr_files; 4588 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 4589 if (status != 0) { 4590 if (PrintMiscellaneous && (Verbose || WizardMode)) 4591 perror("os::init_2 getrlimit failed"); 4592 } else { 4593 nbr_files.rlim_cur = nbr_files.rlim_max; 4594 4595#ifdef __APPLE__ 4596 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 4597 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 4598 // be used instead 4599 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 4600#endif 4601 4602 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 4603 if (status != 0) { 4604 if (PrintMiscellaneous && (Verbose || WizardMode)) 4605 perror("os::init_2 setrlimit failed"); 4606 } 4607 } 4608 } 4609 4610#ifndef _ALLBSD_SOURCE 4611 // Initialize lock used to serialize thread creation (see os::create_thread) 4612 Bsd::set_createThread_lock(new Mutex(Mutex::leaf, "createThread_lock", false)); 4613#endif 4614 4615 // at-exit methods are called in the reverse order of their registration. 4616 // atexit functions are called on return from main or as a result of a 4617 // call to exit(3C). There can be only 32 of these functions registered 4618 // and atexit() does not set errno. 4619 4620 if (PerfAllowAtExitRegistration) { 4621 // only register atexit functions if PerfAllowAtExitRegistration is set. 4622 // atexit functions can be delayed until process exit time, which 4623 // can be problematic for embedded VM situations. Embedded VMs should 4624 // call DestroyJavaVM() to assure that VM resources are released. 4625 4626 // note: perfMemory_exit_helper atexit function may be removed in 4627 // the future if the appropriate cleanup code can be added to the 4628 // VM_Exit VMOperation's doit method. 4629 if (atexit(perfMemory_exit_helper) != 0) { 4630 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 4631 } 4632 } 4633 4634 // initialize thread priority policy 4635 prio_init(); 4636 4637#ifdef __APPLE__ 4638 // dynamically link to objective c gc registration 4639 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 4640 if (handleLibObjc != NULL) { 4641 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 4642 } 4643#endif 4644 4645 return JNI_OK; 4646} 4647 4648// this is called at the end of vm_initialization 4649void os::init_3(void) { } 4650 4651// Mark the polling page as unreadable 4652void os::make_polling_page_unreadable(void) { 4653 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 4654 fatal("Could not disable polling page"); 4655}; 4656 4657// Mark the polling page as readable 4658void os::make_polling_page_readable(void) { 4659 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 4660 fatal("Could not enable polling page"); 4661 } 4662}; 4663 4664int os::active_processor_count() { 4665#ifdef _ALLBSD_SOURCE 4666 return _processor_count; 4667#else 4668 // Bsd doesn't yet have a (official) notion of processor sets, 4669 // so just return the number of online processors. 4670 int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN); 4671 assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check"); 4672 return online_cpus; 4673#endif 4674} 4675 4676void os::set_native_thread_name(const char *name) { 4677#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 4678 // This is only supported in Snow Leopard and beyond 4679 if (name != NULL) { 4680 // Add a "Java: " prefix to the name 4681 char buf[MAXTHREADNAMESIZE]; 4682 snprintf(buf, sizeof(buf), "Java: %s", name); 4683 pthread_setname_np(buf); 4684 } 4685#endif 4686} 4687 4688bool os::distribute_processes(uint length, uint* distribution) { 4689 // Not yet implemented. 4690 return false; 4691} 4692 4693bool os::bind_to_processor(uint processor_id) { 4694 // Not yet implemented. 4695 return false; 4696} 4697 4698/// 4699 4700// Suspends the target using the signal mechanism and then grabs the PC before 4701// resuming the target. Used by the flat-profiler only 4702ExtendedPC os::get_thread_pc(Thread* thread) { 4703 // Make sure that it is called by the watcher for the VMThread 4704 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 4705 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 4706 4707 ExtendedPC epc; 4708 4709 OSThread* osthread = thread->osthread(); 4710 if (do_suspend(osthread)) { 4711 if (osthread->ucontext() != NULL) { 4712 epc = os::Bsd::ucontext_get_pc(osthread->ucontext()); 4713 } else { 4714 // NULL context is unexpected, double-check this is the VMThread 4715 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 4716 } 4717 do_resume(osthread); 4718 } 4719 // failure means pthread_kill failed for some reason - arguably this is 4720 // a fatal problem, but such problems are ignored elsewhere 4721 4722 return epc; 4723} 4724 4725int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 4726{ 4727#ifdef _ALLBSD_SOURCE 4728 return pthread_cond_timedwait(_cond, _mutex, _abstime); 4729#else 4730 if (is_NPTL()) { 4731 return pthread_cond_timedwait(_cond, _mutex, _abstime); 4732 } else { 4733#ifndef IA64 4734 // 6292965: BsdThreads pthread_cond_timedwait() resets FPU control 4735 // word back to default 64bit precision if condvar is signaled. Java 4736 // wants 53bit precision. Save and restore current value. 4737 int fpu = get_fpu_control_word(); 4738#endif // IA64 4739 int status = pthread_cond_timedwait(_cond, _mutex, _abstime); 4740#ifndef IA64 4741 set_fpu_control_word(fpu); 4742#endif // IA64 4743 return status; 4744 } 4745#endif 4746} 4747 4748//////////////////////////////////////////////////////////////////////////////// 4749// debug support 4750 4751static address same_page(address x, address y) { 4752 int page_bits = -os::vm_page_size(); 4753 if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits)) 4754 return x; 4755 else if (x > y) 4756 return (address)(intptr_t(y) | ~page_bits) + 1; 4757 else 4758 return (address)(intptr_t(y) & page_bits); 4759} 4760 4761bool os::find(address addr, outputStream* st) { 4762 Dl_info dlinfo; 4763 memset(&dlinfo, 0, sizeof(dlinfo)); 4764 if (dladdr(addr, &dlinfo)) { 4765 st->print(PTR_FORMAT ": ", addr); 4766 if (dlinfo.dli_sname != NULL) { 4767 st->print("%s+%#x", dlinfo.dli_sname, 4768 addr - (intptr_t)dlinfo.dli_saddr); 4769 } else if (dlinfo.dli_fname) { 4770 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 4771 } else { 4772 st->print("<absolute address>"); 4773 } 4774 if (dlinfo.dli_fname) { 4775 st->print(" in %s", dlinfo.dli_fname); 4776 } 4777 if (dlinfo.dli_fbase) { 4778 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 4779 } 4780 st->cr(); 4781 4782 if (Verbose) { 4783 // decode some bytes around the PC 4784 address begin = same_page(addr-40, addr); 4785 address end = same_page(addr+40, addr); 4786 address lowest = (address) dlinfo.dli_sname; 4787 if (!lowest) lowest = (address) dlinfo.dli_fbase; 4788 if (begin < lowest) begin = lowest; 4789 Dl_info dlinfo2; 4790 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr 4791 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 4792 end = (address) dlinfo2.dli_saddr; 4793 Disassembler::decode(begin, end, st); 4794 } 4795 return true; 4796 } 4797 return false; 4798} 4799 4800//////////////////////////////////////////////////////////////////////////////// 4801// misc 4802 4803// This does not do anything on Bsd. This is basically a hook for being 4804// able to use structured exception handling (thread-local exception filters) 4805// on, e.g., Win32. 4806void 4807os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 4808 JavaCallArguments* args, Thread* thread) { 4809 f(value, method, args, thread); 4810} 4811 4812void os::print_statistics() { 4813} 4814 4815int os::message_box(const char* title, const char* message) { 4816 int i; 4817 fdStream err(defaultStream::error_fd()); 4818 for (i = 0; i < 78; i++) err.print_raw("="); 4819 err.cr(); 4820 err.print_raw_cr(title); 4821 for (i = 0; i < 78; i++) err.print_raw("-"); 4822 err.cr(); 4823 err.print_raw_cr(message); 4824 for (i = 0; i < 78; i++) err.print_raw("="); 4825 err.cr(); 4826 4827 char buf[16]; 4828 // Prevent process from exiting upon "read error" without consuming all CPU 4829 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 4830 4831 return buf[0] == 'y' || buf[0] == 'Y'; 4832} 4833 4834int os::stat(const char *path, struct stat *sbuf) { 4835 char pathbuf[MAX_PATH]; 4836 if (strlen(path) > MAX_PATH - 1) { 4837 errno = ENAMETOOLONG; 4838 return -1; 4839 } 4840 os::native_path(strcpy(pathbuf, path)); 4841 return ::stat(pathbuf, sbuf); 4842} 4843 4844bool os::check_heap(bool force) { 4845 return true; 4846} 4847 4848int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 4849 return ::vsnprintf(buf, count, format, args); 4850} 4851 4852// Is a (classpath) directory empty? 4853bool os::dir_is_empty(const char* path) { 4854 DIR *dir = NULL; 4855 struct dirent *ptr; 4856 4857 dir = opendir(path); 4858 if (dir == NULL) return true; 4859 4860 /* Scan the directory */ 4861 bool result = true; 4862 char buf[sizeof(struct dirent) + MAX_PATH]; 4863 while (result && (ptr = ::readdir(dir)) != NULL) { 4864 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 4865 result = false; 4866 } 4867 } 4868 closedir(dir); 4869 return result; 4870} 4871 4872// This code originates from JDK's sysOpen and open64_w 4873// from src/solaris/hpi/src/system_md.c 4874 4875#ifndef O_DELETE 4876#define O_DELETE 0x10000 4877#endif 4878 4879// Open a file. Unlink the file immediately after open returns 4880// if the specified oflag has the O_DELETE flag set. 4881// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 4882 4883int os::open(const char *path, int oflag, int mode) { 4884 4885 if (strlen(path) > MAX_PATH - 1) { 4886 errno = ENAMETOOLONG; 4887 return -1; 4888 } 4889 int fd; 4890 int o_delete = (oflag & O_DELETE); 4891 oflag = oflag & ~O_DELETE; 4892 4893 fd = ::open(path, oflag, mode); 4894 if (fd == -1) return -1; 4895 4896 //If the open succeeded, the file might still be a directory 4897 { 4898 struct stat buf; 4899 int ret = ::fstat(fd, &buf); 4900 int st_mode = buf.st_mode; 4901 4902 if (ret != -1) { 4903 if ((st_mode & S_IFMT) == S_IFDIR) { 4904 errno = EISDIR; 4905 ::close(fd); 4906 return -1; 4907 } 4908 } else { 4909 ::close(fd); 4910 return -1; 4911 } 4912 } 4913 4914 /* 4915 * All file descriptors that are opened in the JVM and not 4916 * specifically destined for a subprocess should have the 4917 * close-on-exec flag set. If we don't set it, then careless 3rd 4918 * party native code might fork and exec without closing all 4919 * appropriate file descriptors (e.g. as we do in closeDescriptors in 4920 * UNIXProcess.c), and this in turn might: 4921 * 4922 * - cause end-of-file to fail to be detected on some file 4923 * descriptors, resulting in mysterious hangs, or 4924 * 4925 * - might cause an fopen in the subprocess to fail on a system 4926 * suffering from bug 1085341. 4927 * 4928 * (Yes, the default setting of the close-on-exec flag is a Unix 4929 * design flaw) 4930 * 4931 * See: 4932 * 1085341: 32-bit stdio routines should support file descriptors >255 4933 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 4934 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 4935 */ 4936#ifdef FD_CLOEXEC 4937 { 4938 int flags = ::fcntl(fd, F_GETFD); 4939 if (flags != -1) 4940 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 4941 } 4942#endif 4943 4944 if (o_delete != 0) { 4945 ::unlink(path); 4946 } 4947 return fd; 4948} 4949 4950 4951// create binary file, rewriting existing file if required 4952int os::create_binary_file(const char* path, bool rewrite_existing) { 4953 int oflags = O_WRONLY | O_CREAT; 4954 if (!rewrite_existing) { 4955 oflags |= O_EXCL; 4956 } 4957 return ::open(path, oflags, S_IREAD | S_IWRITE); 4958} 4959 4960// return current position of file pointer 4961jlong os::current_file_offset(int fd) { 4962 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 4963} 4964 4965// move file pointer to the specified offset 4966jlong os::seek_to_file_offset(int fd, jlong offset) { 4967 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 4968} 4969 4970// This code originates from JDK's sysAvailable 4971// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 4972 4973int os::available(int fd, jlong *bytes) { 4974 jlong cur, end; 4975 int mode; 4976 struct stat buf; 4977 4978 if (::fstat(fd, &buf) >= 0) { 4979 mode = buf.st_mode; 4980 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 4981 /* 4982 * XXX: is the following call interruptible? If so, this might 4983 * need to go through the INTERRUPT_IO() wrapper as for other 4984 * blocking, interruptible calls in this file. 4985 */ 4986 int n; 4987 if (::ioctl(fd, FIONREAD, &n) >= 0) { 4988 *bytes = n; 4989 return 1; 4990 } 4991 } 4992 } 4993 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 4994 return 0; 4995 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 4996 return 0; 4997 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 4998 return 0; 4999 } 5000 *bytes = end - cur; 5001 return 1; 5002} 5003 5004int os::socket_available(int fd, jint *pbytes) { 5005 if (fd < 0) 5006 return OS_OK; 5007 5008 int ret; 5009 5010 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 5011 5012 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 5013 // is expected to return 0 on failure and 1 on success to the jdk. 5014 5015 return (ret == OS_ERR) ? 0 : 1; 5016} 5017 5018// Map a block of memory. 5019char* os::map_memory(int fd, const char* file_name, size_t file_offset, 5020 char *addr, size_t bytes, bool read_only, 5021 bool allow_exec) { 5022 int prot; 5023 int flags; 5024 5025 if (read_only) { 5026 prot = PROT_READ; 5027 flags = MAP_SHARED; 5028 } else { 5029 prot = PROT_READ | PROT_WRITE; 5030 flags = MAP_PRIVATE; 5031 } 5032 5033 if (allow_exec) { 5034 prot |= PROT_EXEC; 5035 } 5036 5037 if (addr != NULL) { 5038 flags |= MAP_FIXED; 5039 } 5040 5041 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 5042 fd, file_offset); 5043 if (mapped_address == MAP_FAILED) { 5044 return NULL; 5045 } 5046 return mapped_address; 5047} 5048 5049 5050// Remap a block of memory. 5051char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 5052 char *addr, size_t bytes, bool read_only, 5053 bool allow_exec) { 5054 // same as map_memory() on this OS 5055 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 5056 allow_exec); 5057} 5058 5059 5060// Unmap a block of memory. 5061bool os::unmap_memory(char* addr, size_t bytes) { 5062 return munmap(addr, bytes) == 0; 5063} 5064 5065#ifndef _ALLBSD_SOURCE 5066static jlong slow_thread_cpu_time(Thread *thread, bool user_sys_cpu_time); 5067 5068static clockid_t thread_cpu_clockid(Thread* thread) { 5069 pthread_t tid = thread->osthread()->pthread_id(); 5070 clockid_t clockid; 5071 5072 // Get thread clockid 5073 int rc = os::Bsd::pthread_getcpuclockid(tid, &clockid); 5074 assert(rc == 0, "pthread_getcpuclockid is expected to return 0 code"); 5075 return clockid; 5076} 5077#endif 5078 5079// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 5080// are used by JVM M&M and JVMTI to get user+sys or user CPU time 5081// of a thread. 5082// 5083// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 5084// the fast estimate available on the platform. 5085 5086jlong os::current_thread_cpu_time() { 5087#ifdef __APPLE__ 5088 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 5089#elif !defined(_ALLBSD_SOURCE) 5090 if (os::Bsd::supports_fast_thread_cpu_time()) { 5091 return os::Bsd::fast_thread_cpu_time(CLOCK_THREAD_CPUTIME_ID); 5092 } else { 5093 // return user + sys since the cost is the same 5094 return slow_thread_cpu_time(Thread::current(), true /* user + sys */); 5095 } 5096#endif 5097} 5098 5099jlong os::thread_cpu_time(Thread* thread) { 5100#ifndef _ALLBSD_SOURCE 5101 // consistent with what current_thread_cpu_time() returns 5102 if (os::Bsd::supports_fast_thread_cpu_time()) { 5103 return os::Bsd::fast_thread_cpu_time(thread_cpu_clockid(thread)); 5104 } else { 5105 return slow_thread_cpu_time(thread, true /* user + sys */); 5106 } 5107#endif 5108} 5109 5110jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 5111#ifdef __APPLE__ 5112 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 5113#elif !defined(_ALLBSD_SOURCE) 5114 if (user_sys_cpu_time && os::Bsd::supports_fast_thread_cpu_time()) { 5115 return os::Bsd::fast_thread_cpu_time(CLOCK_THREAD_CPUTIME_ID); 5116 } else { 5117 return slow_thread_cpu_time(Thread::current(), user_sys_cpu_time); 5118 } 5119#endif 5120} 5121 5122jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 5123#ifdef __APPLE__ 5124 struct thread_basic_info tinfo; 5125 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 5126 kern_return_t kr; 5127 mach_port_t mach_thread; 5128 5129 mach_thread = pthread_mach_thread_np(thread->osthread()->thread_id()); 5130 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 5131 if (kr != KERN_SUCCESS) 5132 return -1; 5133 5134 if (user_sys_cpu_time) { 5135 jlong nanos; 5136 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 5137 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 5138 return nanos; 5139 } else { 5140 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 5141 } 5142#elif !defined(_ALLBSD_SOURCE) 5143 if (user_sys_cpu_time && os::Bsd::supports_fast_thread_cpu_time()) { 5144 return os::Bsd::fast_thread_cpu_time(thread_cpu_clockid(thread)); 5145 } else { 5146 return slow_thread_cpu_time(thread, user_sys_cpu_time); 5147 } 5148#endif 5149} 5150 5151#ifndef _ALLBSD_SOURCE 5152// 5153// -1 on error. 5154// 5155 5156static jlong slow_thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 5157 static bool proc_pid_cpu_avail = true; 5158 static bool proc_task_unchecked = true; 5159 static const char *proc_stat_path = "/proc/%d/stat"; 5160 pid_t tid = thread->osthread()->thread_id(); 5161 int i; 5162 char *s; 5163 char stat[2048]; 5164 int statlen; 5165 char proc_name[64]; 5166 int count; 5167 long sys_time, user_time; 5168 char string[64]; 5169 char cdummy; 5170 int idummy; 5171 long ldummy; 5172 FILE *fp; 5173 5174 // We first try accessing /proc/<pid>/cpu since this is faster to 5175 // process. If this file is not present (bsd kernels 2.5 and above) 5176 // then we open /proc/<pid>/stat. 5177 if ( proc_pid_cpu_avail ) { 5178 sprintf(proc_name, "/proc/%d/cpu", tid); 5179 fp = fopen(proc_name, "r"); 5180 if ( fp != NULL ) { 5181 count = fscanf( fp, "%s %lu %lu\n", string, &user_time, &sys_time); 5182 fclose(fp); 5183 if ( count != 3 ) return -1; 5184 5185 if (user_sys_cpu_time) { 5186 return ((jlong)sys_time + (jlong)user_time) * (1000000000 / clock_tics_per_sec); 5187 } else { 5188 return (jlong)user_time * (1000000000 / clock_tics_per_sec); 5189 } 5190 } 5191 else proc_pid_cpu_avail = false; 5192 } 5193 5194 // The /proc/<tid>/stat aggregates per-process usage on 5195 // new Bsd kernels 2.6+ where NPTL is supported. 5196 // The /proc/self/task/<tid>/stat still has the per-thread usage. 5197 // See bug 6328462. 5198 // There can be no directory /proc/self/task on kernels 2.4 with NPTL 5199 // and possibly in some other cases, so we check its availability. 5200 if (proc_task_unchecked && os::Bsd::is_NPTL()) { 5201 // This is executed only once 5202 proc_task_unchecked = false; 5203 fp = fopen("/proc/self/task", "r"); 5204 if (fp != NULL) { 5205 proc_stat_path = "/proc/self/task/%d/stat"; 5206 fclose(fp); 5207 } 5208 } 5209 5210 sprintf(proc_name, proc_stat_path, tid); 5211 fp = fopen(proc_name, "r"); 5212 if ( fp == NULL ) return -1; 5213 statlen = fread(stat, 1, 2047, fp); 5214 stat[statlen] = '\0'; 5215 fclose(fp); 5216 5217 // Skip pid and the command string. Note that we could be dealing with 5218 // weird command names, e.g. user could decide to rename java launcher 5219 // to "java 1.4.2 :)", then the stat file would look like 5220 // 1234 (java 1.4.2 :)) R ... ... 5221 // We don't really need to know the command string, just find the last 5222 // occurrence of ")" and then start parsing from there. See bug 4726580. 5223 s = strrchr(stat, ')'); 5224 i = 0; 5225 if (s == NULL ) return -1; 5226 5227 // Skip blank chars 5228 do s++; while (isspace(*s)); 5229 5230 count = sscanf(s,"%c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu", 5231 &cdummy, &idummy, &idummy, &idummy, &idummy, &idummy, 5232 &ldummy, &ldummy, &ldummy, &ldummy, &ldummy, 5233 &user_time, &sys_time); 5234 if ( count != 13 ) return -1; 5235 if (user_sys_cpu_time) { 5236 return ((jlong)sys_time + (jlong)user_time) * (1000000000 / clock_tics_per_sec); 5237 } else { 5238 return (jlong)user_time * (1000000000 / clock_tics_per_sec); 5239 } 5240} 5241#endif 5242 5243void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 5244 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 5245 info_ptr->may_skip_backward = false; // elapsed time not wall time 5246 info_ptr->may_skip_forward = false; // elapsed time not wall time 5247 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 5248} 5249 5250void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 5251 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 5252 info_ptr->may_skip_backward = false; // elapsed time not wall time 5253 info_ptr->may_skip_forward = false; // elapsed time not wall time 5254 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 5255} 5256 5257bool os::is_thread_cpu_time_supported() { 5258#ifdef __APPLE__ 5259 return true; 5260#elif defined(_ALLBSD_SOURCE) 5261 return false; 5262#else 5263 return true; 5264#endif 5265} 5266 5267// System loadavg support. Returns -1 if load average cannot be obtained. 5268// Bsd doesn't yet have a (official) notion of processor sets, 5269// so just return the system wide load average. 5270int os::loadavg(double loadavg[], int nelem) { 5271 return ::getloadavg(loadavg, nelem); 5272} 5273 5274void os::pause() { 5275 char filename[MAX_PATH]; 5276 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 5277 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 5278 } else { 5279 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 5280 } 5281 5282 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 5283 if (fd != -1) { 5284 struct stat buf; 5285 ::close(fd); 5286 while (::stat(filename, &buf) == 0) { 5287 (void)::poll(NULL, 0, 100); 5288 } 5289 } else { 5290 jio_fprintf(stderr, 5291 "Could not open pause file '%s', continuing immediately.\n", filename); 5292 } 5293} 5294 5295 5296// Refer to the comments in os_solaris.cpp park-unpark. 5297// 5298// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 5299// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 5300// For specifics regarding the bug see GLIBC BUGID 261237 : 5301// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 5302// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 5303// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 5304// is used. (The simple C test-case provided in the GLIBC bug report manifests the 5305// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 5306// and monitorenter when we're using 1-0 locking. All those operations may result in 5307// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 5308// of libpthread avoids the problem, but isn't practical. 5309// 5310// Possible remedies: 5311// 5312// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 5313// This is palliative and probabilistic, however. If the thread is preempted 5314// between the call to compute_abstime() and pthread_cond_timedwait(), more 5315// than the minimum period may have passed, and the abstime may be stale (in the 5316// past) resultin in a hang. Using this technique reduces the odds of a hang 5317// but the JVM is still vulnerable, particularly on heavily loaded systems. 5318// 5319// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 5320// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 5321// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 5322// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 5323// thread. 5324// 5325// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 5326// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 5327// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 5328// This also works well. In fact it avoids kernel-level scalability impediments 5329// on certain platforms that don't handle lots of active pthread_cond_timedwait() 5330// timers in a graceful fashion. 5331// 5332// 4. When the abstime value is in the past it appears that control returns 5333// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 5334// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 5335// can avoid the problem by reinitializing the condvar -- by cond_destroy() 5336// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 5337// It may be possible to avoid reinitialization by checking the return 5338// value from pthread_cond_timedwait(). In addition to reinitializing the 5339// condvar we must establish the invariant that cond_signal() is only called 5340// within critical sections protected by the adjunct mutex. This prevents 5341// cond_signal() from "seeing" a condvar that's in the midst of being 5342// reinitialized or that is corrupt. Sadly, this invariant obviates the 5343// desirable signal-after-unlock optimization that avoids futile context switching. 5344// 5345// I'm also concerned that some versions of NTPL might allocate an auxilliary 5346// structure when a condvar is used or initialized. cond_destroy() would 5347// release the helper structure. Our reinitialize-after-timedwait fix 5348// put excessive stress on malloc/free and locks protecting the c-heap. 5349// 5350// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 5351// It may be possible to refine (4) by checking the kernel and NTPL verisons 5352// and only enabling the work-around for vulnerable environments. 5353 5354// utility to compute the abstime argument to timedwait: 5355// millis is the relative timeout time 5356// abstime will be the absolute timeout time 5357// TODO: replace compute_abstime() with unpackTime() 5358 5359static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 5360 if (millis < 0) millis = 0; 5361 struct timeval now; 5362 int status = gettimeofday(&now, NULL); 5363 assert(status == 0, "gettimeofday"); 5364 jlong seconds = millis / 1000; 5365 millis %= 1000; 5366 if (seconds > 50000000) { // see man cond_timedwait(3T) 5367 seconds = 50000000; 5368 } 5369 abstime->tv_sec = now.tv_sec + seconds; 5370 long usec = now.tv_usec + millis * 1000; 5371 if (usec >= 1000000) { 5372 abstime->tv_sec += 1; 5373 usec -= 1000000; 5374 } 5375 abstime->tv_nsec = usec * 1000; 5376 return abstime; 5377} 5378 5379 5380// Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 5381// Conceptually TryPark() should be equivalent to park(0). 5382 5383int os::PlatformEvent::TryPark() { 5384 for (;;) { 5385 const int v = _Event ; 5386 guarantee ((v == 0) || (v == 1), "invariant") ; 5387 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 5388 } 5389} 5390 5391void os::PlatformEvent::park() { // AKA "down()" 5392 // Invariant: Only the thread associated with the Event/PlatformEvent 5393 // may call park(). 5394 // TODO: assert that _Assoc != NULL or _Assoc == Self 5395 int v ; 5396 for (;;) { 5397 v = _Event ; 5398 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 5399 } 5400 guarantee (v >= 0, "invariant") ; 5401 if (v == 0) { 5402 // Do this the hard way by blocking ... 5403 int status = pthread_mutex_lock(_mutex); 5404 assert_status(status == 0, status, "mutex_lock"); 5405 guarantee (_nParked == 0, "invariant") ; 5406 ++ _nParked ; 5407 while (_Event < 0) { 5408 status = pthread_cond_wait(_cond, _mutex); 5409 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 5410 // Treat this the same as if the wait was interrupted 5411 if (status == ETIMEDOUT) { status = EINTR; } 5412 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 5413 } 5414 -- _nParked ; 5415 5416 // In theory we could move the ST of 0 into _Event past the unlock(), 5417 // but then we'd need a MEMBAR after the ST. 5418 _Event = 0 ; 5419 status = pthread_mutex_unlock(_mutex); 5420 assert_status(status == 0, status, "mutex_unlock"); 5421 } 5422 guarantee (_Event >= 0, "invariant") ; 5423} 5424 5425int os::PlatformEvent::park(jlong millis) { 5426 guarantee (_nParked == 0, "invariant") ; 5427 5428 int v ; 5429 for (;;) { 5430 v = _Event ; 5431 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 5432 } 5433 guarantee (v >= 0, "invariant") ; 5434 if (v != 0) return OS_OK ; 5435 5436 // We do this the hard way, by blocking the thread. 5437 // Consider enforcing a minimum timeout value. 5438 struct timespec abst; 5439 compute_abstime(&abst, millis); 5440 5441 int ret = OS_TIMEOUT; 5442 int status = pthread_mutex_lock(_mutex); 5443 assert_status(status == 0, status, "mutex_lock"); 5444 guarantee (_nParked == 0, "invariant") ; 5445 ++_nParked ; 5446 5447 // Object.wait(timo) will return because of 5448 // (a) notification 5449 // (b) timeout 5450 // (c) thread.interrupt 5451 // 5452 // Thread.interrupt and object.notify{All} both call Event::set. 5453 // That is, we treat thread.interrupt as a special case of notification. 5454 // The underlying Solaris implementation, cond_timedwait, admits 5455 // spurious/premature wakeups, but the JLS/JVM spec prevents the 5456 // JVM from making those visible to Java code. As such, we must 5457 // filter out spurious wakeups. We assume all ETIME returns are valid. 5458 // 5459 // TODO: properly differentiate simultaneous notify+interrupt. 5460 // In that case, we should propagate the notify to another waiter. 5461 5462 while (_Event < 0) { 5463 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 5464 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 5465 pthread_cond_destroy (_cond); 5466 pthread_cond_init (_cond, NULL) ; 5467 } 5468 assert_status(status == 0 || status == EINTR || 5469 status == ETIMEDOUT, 5470 status, "cond_timedwait"); 5471 if (!FilterSpuriousWakeups) break ; // previous semantics 5472 if (status == ETIMEDOUT) break ; 5473 // We consume and ignore EINTR and spurious wakeups. 5474 } 5475 --_nParked ; 5476 if (_Event >= 0) { 5477 ret = OS_OK; 5478 } 5479 _Event = 0 ; 5480 status = pthread_mutex_unlock(_mutex); 5481 assert_status(status == 0, status, "mutex_unlock"); 5482 assert (_nParked == 0, "invariant") ; 5483 return ret; 5484} 5485 5486void os::PlatformEvent::unpark() { 5487 int v, AnyWaiters ; 5488 for (;;) { 5489 v = _Event ; 5490 if (v > 0) { 5491 // The LD of _Event could have reordered or be satisfied 5492 // by a read-aside from this processor's write buffer. 5493 // To avoid problems execute a barrier and then 5494 // ratify the value. 5495 OrderAccess::fence() ; 5496 if (_Event == v) return ; 5497 continue ; 5498 } 5499 if (Atomic::cmpxchg (v+1, &_Event, v) == v) break ; 5500 } 5501 if (v < 0) { 5502 // Wait for the thread associated with the event to vacate 5503 int status = pthread_mutex_lock(_mutex); 5504 assert_status(status == 0, status, "mutex_lock"); 5505 AnyWaiters = _nParked ; 5506 assert (AnyWaiters == 0 || AnyWaiters == 1, "invariant") ; 5507 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 5508 AnyWaiters = 0 ; 5509 pthread_cond_signal (_cond); 5510 } 5511 status = pthread_mutex_unlock(_mutex); 5512 assert_status(status == 0, status, "mutex_unlock"); 5513 if (AnyWaiters != 0) { 5514 status = pthread_cond_signal(_cond); 5515 assert_status(status == 0, status, "cond_signal"); 5516 } 5517 } 5518 5519 // Note that we signal() _after dropping the lock for "immortal" Events. 5520 // This is safe and avoids a common class of futile wakeups. In rare 5521 // circumstances this can cause a thread to return prematurely from 5522 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 5523 // simply re-test the condition and re-park itself. 5524} 5525 5526 5527// JSR166 5528// ------------------------------------------------------- 5529 5530/* 5531 * The solaris and bsd implementations of park/unpark are fairly 5532 * conservative for now, but can be improved. They currently use a 5533 * mutex/condvar pair, plus a a count. 5534 * Park decrements count if > 0, else does a condvar wait. Unpark 5535 * sets count to 1 and signals condvar. Only one thread ever waits 5536 * on the condvar. Contention seen when trying to park implies that someone 5537 * is unparking you, so don't wait. And spurious returns are fine, so there 5538 * is no need to track notifications. 5539 */ 5540 5541#define MAX_SECS 100000000 5542/* 5543 * This code is common to bsd and solaris and will be moved to a 5544 * common place in dolphin. 5545 * 5546 * The passed in time value is either a relative time in nanoseconds 5547 * or an absolute time in milliseconds. Either way it has to be unpacked 5548 * into suitable seconds and nanoseconds components and stored in the 5549 * given timespec structure. 5550 * Given time is a 64-bit value and the time_t used in the timespec is only 5551 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 5552 * overflow if times way in the future are given. Further on Solaris versions 5553 * prior to 10 there is a restriction (see cond_timedwait) that the specified 5554 * number of seconds, in abstime, is less than current_time + 100,000,000. 5555 * As it will be 28 years before "now + 100000000" will overflow we can 5556 * ignore overflow and just impose a hard-limit on seconds using the value 5557 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 5558 * years from "now". 5559 */ 5560 5561static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 5562 assert (time > 0, "convertTime"); 5563 5564 struct timeval now; 5565 int status = gettimeofday(&now, NULL); 5566 assert(status == 0, "gettimeofday"); 5567 5568 time_t max_secs = now.tv_sec + MAX_SECS; 5569 5570 if (isAbsolute) { 5571 jlong secs = time / 1000; 5572 if (secs > max_secs) { 5573 absTime->tv_sec = max_secs; 5574 } 5575 else { 5576 absTime->tv_sec = secs; 5577 } 5578 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 5579 } 5580 else { 5581 jlong secs = time / NANOSECS_PER_SEC; 5582 if (secs >= MAX_SECS) { 5583 absTime->tv_sec = max_secs; 5584 absTime->tv_nsec = 0; 5585 } 5586 else { 5587 absTime->tv_sec = now.tv_sec + secs; 5588 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 5589 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 5590 absTime->tv_nsec -= NANOSECS_PER_SEC; 5591 ++absTime->tv_sec; // note: this must be <= max_secs 5592 } 5593 } 5594 } 5595 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 5596 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 5597 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 5598 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 5599} 5600 5601void Parker::park(bool isAbsolute, jlong time) { 5602 // Optional fast-path check: 5603 // Return immediately if a permit is available. 5604 if (_counter > 0) { 5605 _counter = 0 ; 5606 OrderAccess::fence(); 5607 return ; 5608 } 5609 5610 Thread* thread = Thread::current(); 5611 assert(thread->is_Java_thread(), "Must be JavaThread"); 5612 JavaThread *jt = (JavaThread *)thread; 5613 5614 // Optional optimization -- avoid state transitions if there's an interrupt pending. 5615 // Check interrupt before trying to wait 5616 if (Thread::is_interrupted(thread, false)) { 5617 return; 5618 } 5619 5620 // Next, demultiplex/decode time arguments 5621 struct timespec absTime; 5622 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 5623 return; 5624 } 5625 if (time > 0) { 5626 unpackTime(&absTime, isAbsolute, time); 5627 } 5628 5629 5630 // Enter safepoint region 5631 // Beware of deadlocks such as 6317397. 5632 // The per-thread Parker:: mutex is a classic leaf-lock. 5633 // In particular a thread must never block on the Threads_lock while 5634 // holding the Parker:: mutex. If safepoints are pending both the 5635 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 5636 ThreadBlockInVM tbivm(jt); 5637 5638 // Don't wait if cannot get lock since interference arises from 5639 // unblocking. Also. check interrupt before trying wait 5640 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 5641 return; 5642 } 5643 5644 int status ; 5645 if (_counter > 0) { // no wait needed 5646 _counter = 0; 5647 status = pthread_mutex_unlock(_mutex); 5648 assert (status == 0, "invariant") ; 5649 OrderAccess::fence(); 5650 return; 5651 } 5652 5653#ifdef ASSERT 5654 // Don't catch signals while blocked; let the running threads have the signals. 5655 // (This allows a debugger to break into the running thread.) 5656 sigset_t oldsigs; 5657 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 5658 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 5659#endif 5660 5661 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 5662 jt->set_suspend_equivalent(); 5663 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 5664 5665 if (time == 0) { 5666 status = pthread_cond_wait (_cond, _mutex) ; 5667 } else { 5668 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 5669 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 5670 pthread_cond_destroy (_cond) ; 5671 pthread_cond_init (_cond, NULL); 5672 } 5673 } 5674 assert_status(status == 0 || status == EINTR || 5675 status == ETIMEDOUT, 5676 status, "cond_timedwait"); 5677 5678#ifdef ASSERT 5679 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 5680#endif 5681 5682 _counter = 0 ; 5683 status = pthread_mutex_unlock(_mutex) ; 5684 assert_status(status == 0, status, "invariant") ; 5685 // If externally suspended while waiting, re-suspend 5686 if (jt->handle_special_suspend_equivalent_condition()) { 5687 jt->java_suspend_self(); 5688 } 5689 5690 OrderAccess::fence(); 5691} 5692 5693void Parker::unpark() { 5694 int s, status ; 5695 status = pthread_mutex_lock(_mutex); 5696 assert (status == 0, "invariant") ; 5697 s = _counter; 5698 _counter = 1; 5699 if (s < 1) { 5700 if (WorkAroundNPTLTimedWaitHang) { 5701 status = pthread_cond_signal (_cond) ; 5702 assert (status == 0, "invariant") ; 5703 status = pthread_mutex_unlock(_mutex); 5704 assert (status == 0, "invariant") ; 5705 } else { 5706 status = pthread_mutex_unlock(_mutex); 5707 assert (status == 0, "invariant") ; 5708 status = pthread_cond_signal (_cond) ; 5709 assert (status == 0, "invariant") ; 5710 } 5711 } else { 5712 pthread_mutex_unlock(_mutex); 5713 assert (status == 0, "invariant") ; 5714 } 5715} 5716 5717 5718/* Darwin has no "environ" in a dynamic library. */ 5719#ifdef __APPLE__ 5720#include <crt_externs.h> 5721#define environ (*_NSGetEnviron()) 5722#else 5723extern char** environ; 5724#endif 5725 5726// Run the specified command in a separate process. Return its exit value, 5727// or -1 on failure (e.g. can't fork a new process). 5728// Unlike system(), this function can be called from signal handler. It 5729// doesn't block SIGINT et al. 5730int os::fork_and_exec(char* cmd) { 5731 const char * argv[4] = {"sh", "-c", cmd, NULL}; 5732 5733 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 5734 // pthread_atfork handlers and reset pthread library. All we need is a 5735 // separate process to execve. Make a direct syscall to fork process. 5736 // On IA64 there's no fork syscall, we have to use fork() and hope for 5737 // the best... 5738 pid_t pid = fork(); 5739 5740 if (pid < 0) { 5741 // fork failed 5742 return -1; 5743 5744 } else if (pid == 0) { 5745 // child process 5746 5747 // execve() in BsdThreads will call pthread_kill_other_threads_np() 5748 // first to kill every thread on the thread list. Because this list is 5749 // not reset by fork() (see notes above), execve() will instead kill 5750 // every thread in the parent process. We know this is the only thread 5751 // in the new process, so make a system call directly. 5752 // IA64 should use normal execve() from glibc to match the glibc fork() 5753 // above. 5754 execve("/bin/sh", (char* const*)argv, environ); 5755 5756 // execve failed 5757 _exit(-1); 5758 5759 } else { 5760 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 5761 // care about the actual exit code, for now. 5762 5763 int status; 5764 5765 // Wait for the child process to exit. This returns immediately if 5766 // the child has already exited. */ 5767 while (waitpid(pid, &status, 0) < 0) { 5768 switch (errno) { 5769 case ECHILD: return 0; 5770 case EINTR: break; 5771 default: return -1; 5772 } 5773 } 5774 5775 if (WIFEXITED(status)) { 5776 // The child exited normally; get its exit code. 5777 return WEXITSTATUS(status); 5778 } else if (WIFSIGNALED(status)) { 5779 // The child exited because of a signal 5780 // The best value to return is 0x80 + signal number, 5781 // because that is what all Unix shells do, and because 5782 // it allows callers to distinguish between process exit and 5783 // process death by signal. 5784 return 0x80 + WTERMSIG(status); 5785 } else { 5786 // Unknown exit code; pass it through 5787 return status; 5788 } 5789 } 5790} 5791 5792// is_headless_jre() 5793// 5794// Test for the existence of xawt/libmawt.so or libawt_xawt.so 5795// in order to report if we are running in a headless jre 5796// 5797// Since JDK8 xawt/libmawt.so was moved into the same directory 5798// as libawt.so, and renamed libawt_xawt.so 5799// 5800bool os::is_headless_jre() { 5801 struct stat statbuf; 5802 char buf[MAXPATHLEN]; 5803 char libmawtpath[MAXPATHLEN]; 5804 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 5805 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 5806 char *p; 5807 5808 // Get path to libjvm.so 5809 os::jvm_path(buf, sizeof(buf)); 5810 5811 // Get rid of libjvm.so 5812 p = strrchr(buf, '/'); 5813 if (p == NULL) return false; 5814 else *p = '\0'; 5815 5816 // Get rid of client or server 5817 p = strrchr(buf, '/'); 5818 if (p == NULL) return false; 5819 else *p = '\0'; 5820 5821 // check xawt/libmawt.so 5822 strcpy(libmawtpath, buf); 5823 strcat(libmawtpath, xawtstr); 5824 if (::stat(libmawtpath, &statbuf) == 0) return false; 5825 5826 // check libawt_xawt.so 5827 strcpy(libmawtpath, buf); 5828 strcat(libmawtpath, new_xawtstr); 5829 if (::stat(libmawtpath, &statbuf) == 0) return false; 5830 5831 return true; 5832} 5833