os_bsd.cpp revision 3151:86ce3208eb18
1/* 2 * Copyright (c) 1999, 2012, 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 } 571 572#ifdef __APPLE__ 573 // Apple's Java6 has "." at the beginning of java.library.path. 574 // OpenJDK on Windows has "." at the end of java.library.path. 575 // OpenJDK on Linux and Solaris don't have "." in java.library.path 576 // at all. To ease the transition from Apple's Java6 to OpenJDK7, 577 // "." is appended to the end of java.library.path. Yes, this 578 // could cause a change in behavior, but Apple's Java6 behavior 579 // can be achieved by putting "." at the beginning of the 580 // JAVA_LIBRARY_PATH environment variable. 581 { 582 char *t = ld_library_path; 583 // that's +3 for appending ":." and the trailing '\0' 584 ld_library_path = (char *) malloc(strlen(t) + 3); 585 sprintf(ld_library_path, "%s:%s", t, "."); 586 free(t); 587 } 588#endif 589 590 Arguments::set_library_path(ld_library_path); 591 } 592 593 /* 594 * Extensions directories. 595 * 596 * Note that the space for the colon and the trailing null are provided 597 * by the nulls included by the sizeof operator (so actually one byte more 598 * than necessary is allocated). 599 */ 600 { 601#ifdef __APPLE__ 602 char *buf = malloc(strlen(Arguments::get_java_home()) + 603 sizeof(EXTENSIONS_DIR) + system_ext_size); 604 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" 605 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home()); 606#else 607 char *buf = malloc(strlen(Arguments::get_java_home()) + 608 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR)); 609 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR, 610 Arguments::get_java_home()); 611#endif 612 613 Arguments::set_ext_dirs(buf); 614 } 615 616 /* Endorsed standards default directory. */ 617 { 618 char * buf; 619 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR)); 620 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); 621 Arguments::set_endorsed_dirs(buf); 622 } 623 } 624 625#ifdef __APPLE__ 626#undef SYS_EXTENSIONS_DIR 627#endif 628#undef malloc 629#undef getenv 630#undef EXTENSIONS_DIR 631#undef ENDORSED_DIR 632 633 // Done 634 return; 635} 636 637//////////////////////////////////////////////////////////////////////////////// 638// breakpoint support 639 640void os::breakpoint() { 641 BREAKPOINT; 642} 643 644extern "C" void breakpoint() { 645 // use debugger to set breakpoint here 646} 647 648//////////////////////////////////////////////////////////////////////////////// 649// signal support 650 651debug_only(static bool signal_sets_initialized = false); 652static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; 653 654bool os::Bsd::is_sig_ignored(int sig) { 655 struct sigaction oact; 656 sigaction(sig, (struct sigaction*)NULL, &oact); 657 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) 658 : CAST_FROM_FN_PTR(void*, oact.sa_handler); 659 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) 660 return true; 661 else 662 return false; 663} 664 665void os::Bsd::signal_sets_init() { 666 // Should also have an assertion stating we are still single-threaded. 667 assert(!signal_sets_initialized, "Already initialized"); 668 // Fill in signals that are necessarily unblocked for all threads in 669 // the VM. Currently, we unblock the following signals: 670 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden 671 // by -Xrs (=ReduceSignalUsage)); 672 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all 673 // other threads. The "ReduceSignalUsage" boolean tells us not to alter 674 // the dispositions or masks wrt these signals. 675 // Programs embedding the VM that want to use the above signals for their 676 // own purposes must, at this time, use the "-Xrs" option to prevent 677 // interference with shutdown hooks and BREAK_SIGNAL thread dumping. 678 // (See bug 4345157, and other related bugs). 679 // In reality, though, unblocking these signals is really a nop, since 680 // these signals are not blocked by default. 681 sigemptyset(&unblocked_sigs); 682 sigemptyset(&allowdebug_blocked_sigs); 683 sigaddset(&unblocked_sigs, SIGILL); 684 sigaddset(&unblocked_sigs, SIGSEGV); 685 sigaddset(&unblocked_sigs, SIGBUS); 686 sigaddset(&unblocked_sigs, SIGFPE); 687 sigaddset(&unblocked_sigs, SR_signum); 688 689 if (!ReduceSignalUsage) { 690 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { 691 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); 692 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); 693 } 694 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { 695 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); 696 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); 697 } 698 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { 699 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); 700 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); 701 } 702 } 703 // Fill in signals that are blocked by all but the VM thread. 704 sigemptyset(&vm_sigs); 705 if (!ReduceSignalUsage) 706 sigaddset(&vm_sigs, BREAK_SIGNAL); 707 debug_only(signal_sets_initialized = true); 708 709} 710 711// These are signals that are unblocked while a thread is running Java. 712// (For some reason, they get blocked by default.) 713sigset_t* os::Bsd::unblocked_signals() { 714 assert(signal_sets_initialized, "Not initialized"); 715 return &unblocked_sigs; 716} 717 718// These are the signals that are blocked while a (non-VM) thread is 719// running Java. Only the VM thread handles these signals. 720sigset_t* os::Bsd::vm_signals() { 721 assert(signal_sets_initialized, "Not initialized"); 722 return &vm_sigs; 723} 724 725// These are signals that are blocked during cond_wait to allow debugger in 726sigset_t* os::Bsd::allowdebug_blocked_signals() { 727 assert(signal_sets_initialized, "Not initialized"); 728 return &allowdebug_blocked_sigs; 729} 730 731void os::Bsd::hotspot_sigmask(Thread* thread) { 732 733 //Save caller's signal mask before setting VM signal mask 734 sigset_t caller_sigmask; 735 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); 736 737 OSThread* osthread = thread->osthread(); 738 osthread->set_caller_sigmask(caller_sigmask); 739 740 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); 741 742 if (!ReduceSignalUsage) { 743 if (thread->is_VM_thread()) { 744 // Only the VM thread handles BREAK_SIGNAL ... 745 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); 746 } else { 747 // ... all other threads block BREAK_SIGNAL 748 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); 749 } 750 } 751} 752 753#ifndef _ALLBSD_SOURCE 754////////////////////////////////////////////////////////////////////////////// 755// detecting pthread library 756 757void os::Bsd::libpthread_init() { 758 // Save glibc and pthread version strings. Note that _CS_GNU_LIBC_VERSION 759 // and _CS_GNU_LIBPTHREAD_VERSION are supported in glibc >= 2.3.2. Use a 760 // generic name for earlier versions. 761 // Define macros here so we can build HotSpot on old systems. 762# ifndef _CS_GNU_LIBC_VERSION 763# define _CS_GNU_LIBC_VERSION 2 764# endif 765# ifndef _CS_GNU_LIBPTHREAD_VERSION 766# define _CS_GNU_LIBPTHREAD_VERSION 3 767# endif 768 769 size_t n = confstr(_CS_GNU_LIBC_VERSION, NULL, 0); 770 if (n > 0) { 771 char *str = (char *)malloc(n); 772 confstr(_CS_GNU_LIBC_VERSION, str, n); 773 os::Bsd::set_glibc_version(str); 774 } else { 775 // _CS_GNU_LIBC_VERSION is not supported, try gnu_get_libc_version() 776 static char _gnu_libc_version[32]; 777 jio_snprintf(_gnu_libc_version, sizeof(_gnu_libc_version), 778 "glibc %s %s", gnu_get_libc_version(), gnu_get_libc_release()); 779 os::Bsd::set_glibc_version(_gnu_libc_version); 780 } 781 782 n = confstr(_CS_GNU_LIBPTHREAD_VERSION, NULL, 0); 783 if (n > 0) { 784 char *str = (char *)malloc(n); 785 confstr(_CS_GNU_LIBPTHREAD_VERSION, str, n); 786 // Vanilla RH-9 (glibc 2.3.2) has a bug that confstr() always tells 787 // us "NPTL-0.29" even we are running with BsdThreads. Check if this 788 // is the case. BsdThreads has a hard limit on max number of threads. 789 // So sysconf(_SC_THREAD_THREADS_MAX) will return a positive value. 790 // On the other hand, NPTL does not have such a limit, sysconf() 791 // will return -1 and errno is not changed. Check if it is really NPTL. 792 if (strcmp(os::Bsd::glibc_version(), "glibc 2.3.2") == 0 && 793 strstr(str, "NPTL") && 794 sysconf(_SC_THREAD_THREADS_MAX) > 0) { 795 free(str); 796 os::Bsd::set_libpthread_version("bsdthreads"); 797 } else { 798 os::Bsd::set_libpthread_version(str); 799 } 800 } else { 801 // glibc before 2.3.2 only has BsdThreads. 802 os::Bsd::set_libpthread_version("bsdthreads"); 803 } 804 805 if (strstr(libpthread_version(), "NPTL")) { 806 os::Bsd::set_is_NPTL(); 807 } else { 808 os::Bsd::set_is_BsdThreads(); 809 } 810 811 // BsdThreads have two flavors: floating-stack mode, which allows variable 812 // stack size; and fixed-stack mode. NPTL is always floating-stack. 813 if (os::Bsd::is_NPTL() || os::Bsd::supports_variable_stack_size()) { 814 os::Bsd::set_is_floating_stack(); 815 } 816} 817 818///////////////////////////////////////////////////////////////////////////// 819// thread stack 820 821// Force Bsd kernel to expand current thread stack. If "bottom" is close 822// to the stack guard, caller should block all signals. 823// 824// MAP_GROWSDOWN: 825// A special mmap() flag that is used to implement thread stacks. It tells 826// kernel that the memory region should extend downwards when needed. This 827// allows early versions of BsdThreads to only mmap the first few pages 828// when creating a new thread. Bsd kernel will automatically expand thread 829// stack as needed (on page faults). 830// 831// However, because the memory region of a MAP_GROWSDOWN stack can grow on 832// demand, if a page fault happens outside an already mapped MAP_GROWSDOWN 833// region, it's hard to tell if the fault is due to a legitimate stack 834// access or because of reading/writing non-exist memory (e.g. buffer 835// overrun). As a rule, if the fault happens below current stack pointer, 836// Bsd kernel does not expand stack, instead a SIGSEGV is sent to the 837// application (see Bsd kernel fault.c). 838// 839// This Bsd feature can cause SIGSEGV when VM bangs thread stack for 840// stack overflow detection. 841// 842// Newer version of BsdThreads (since glibc-2.2, or, RH-7.x) and NPTL do 843// not use this flag. However, the stack of initial thread is not created 844// by pthread, it is still MAP_GROWSDOWN. Also it's possible (though 845// unlikely) that user code can create a thread with MAP_GROWSDOWN stack 846// and then attach the thread to JVM. 847// 848// To get around the problem and allow stack banging on Bsd, we need to 849// manually expand thread stack after receiving the SIGSEGV. 850// 851// There are two ways to expand thread stack to address "bottom", we used 852// both of them in JVM before 1.5: 853// 1. adjust stack pointer first so that it is below "bottom", and then 854// touch "bottom" 855// 2. mmap() the page in question 856// 857// Now alternate signal stack is gone, it's harder to use 2. For instance, 858// if current sp is already near the lower end of page 101, and we need to 859// call mmap() to map page 100, it is possible that part of the mmap() frame 860// will be placed in page 100. When page 100 is mapped, it is zero-filled. 861// That will destroy the mmap() frame and cause VM to crash. 862// 863// The following code works by adjusting sp first, then accessing the "bottom" 864// page to force a page fault. Bsd kernel will then automatically expand the 865// stack mapping. 866// 867// _expand_stack_to() assumes its frame size is less than page size, which 868// should always be true if the function is not inlined. 869 870#if __GNUC__ < 3 // gcc 2.x does not support noinline attribute 871#define NOINLINE 872#else 873#define NOINLINE __attribute__ ((noinline)) 874#endif 875 876static void _expand_stack_to(address bottom) NOINLINE; 877 878static void _expand_stack_to(address bottom) { 879 address sp; 880 size_t size; 881 volatile char *p; 882 883 // Adjust bottom to point to the largest address within the same page, it 884 // gives us a one-page buffer if alloca() allocates slightly more memory. 885 bottom = (address)align_size_down((uintptr_t)bottom, os::Bsd::page_size()); 886 bottom += os::Bsd::page_size() - 1; 887 888 // sp might be slightly above current stack pointer; if that's the case, we 889 // will alloca() a little more space than necessary, which is OK. Don't use 890 // os::current_stack_pointer(), as its result can be slightly below current 891 // stack pointer, causing us to not alloca enough to reach "bottom". 892 sp = (address)&sp; 893 894 if (sp > bottom) { 895 size = sp - bottom; 896 p = (volatile char *)alloca(size); 897 assert(p != NULL && p <= (volatile char *)bottom, "alloca problem?"); 898 p[0] = '\0'; 899 } 900} 901 902bool os::Bsd::manually_expand_stack(JavaThread * t, address addr) { 903 assert(t!=NULL, "just checking"); 904 assert(t->osthread()->expanding_stack(), "expand should be set"); 905 assert(t->stack_base() != NULL, "stack_base was not initialized"); 906 907 if (addr < t->stack_base() && addr >= t->stack_yellow_zone_base()) { 908 sigset_t mask_all, old_sigset; 909 sigfillset(&mask_all); 910 pthread_sigmask(SIG_SETMASK, &mask_all, &old_sigset); 911 _expand_stack_to(addr); 912 pthread_sigmask(SIG_SETMASK, &old_sigset, NULL); 913 return true; 914 } 915 return false; 916} 917#endif 918 919////////////////////////////////////////////////////////////////////////////// 920// create new thread 921 922static address highest_vm_reserved_address(); 923 924// check if it's safe to start a new thread 925static bool _thread_safety_check(Thread* thread) { 926#ifdef _ALLBSD_SOURCE 927 return true; 928#else 929 if (os::Bsd::is_BsdThreads() && !os::Bsd::is_floating_stack()) { 930 // Fixed stack BsdThreads (SuSE Bsd/x86, and some versions of Redhat) 931 // Heap is mmap'ed at lower end of memory space. Thread stacks are 932 // allocated (MAP_FIXED) from high address space. Every thread stack 933 // occupies a fixed size slot (usually 2Mbytes, but user can change 934 // it to other values if they rebuild BsdThreads). 935 // 936 // Problem with MAP_FIXED is that mmap() can still succeed even part of 937 // the memory region has already been mmap'ed. That means if we have too 938 // many threads and/or very large heap, eventually thread stack will 939 // collide with heap. 940 // 941 // Here we try to prevent heap/stack collision by comparing current 942 // stack bottom with the highest address that has been mmap'ed by JVM 943 // plus a safety margin for memory maps created by native code. 944 // 945 // This feature can be disabled by setting ThreadSafetyMargin to 0 946 // 947 if (ThreadSafetyMargin > 0) { 948 address stack_bottom = os::current_stack_base() - os::current_stack_size(); 949 950 // not safe if our stack extends below the safety margin 951 return stack_bottom - ThreadSafetyMargin >= highest_vm_reserved_address(); 952 } else { 953 return true; 954 } 955 } else { 956 // Floating stack BsdThreads or NPTL: 957 // Unlike fixed stack BsdThreads, thread stacks are not MAP_FIXED. When 958 // there's not enough space left, pthread_create() will fail. If we come 959 // here, that means enough space has been reserved for stack. 960 return true; 961 } 962#endif 963} 964 965#ifdef __APPLE__ 966// library handle for calling objc_registerThreadWithCollector() 967// without static linking to the libobjc library 968#define OBJC_LIB "/usr/lib/libobjc.dylib" 969#define OBJC_GCREGISTER "objc_registerThreadWithCollector" 970typedef void (*objc_registerThreadWithCollector_t)(); 971extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; 972objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; 973#endif 974 975// Thread start routine for all newly created threads 976static void *java_start(Thread *thread) { 977 // Try to randomize the cache line index of hot stack frames. 978 // This helps when threads of the same stack traces evict each other's 979 // cache lines. The threads can be either from the same JVM instance, or 980 // from different JVM instances. The benefit is especially true for 981 // processors with hyperthreading technology. 982 static int counter = 0; 983 int pid = os::current_process_id(); 984 alloca(((pid ^ counter++) & 7) * 128); 985 986 ThreadLocalStorage::set_thread(thread); 987 988 OSThread* osthread = thread->osthread(); 989 Monitor* sync = osthread->startThread_lock(); 990 991 // non floating stack BsdThreads needs extra check, see above 992 if (!_thread_safety_check(thread)) { 993 // notify parent thread 994 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 995 osthread->set_state(ZOMBIE); 996 sync->notify_all(); 997 return NULL; 998 } 999 1000#ifdef _ALLBSD_SOURCE 1001 // thread_id is pthread_id on BSD 1002 osthread->set_thread_id(::pthread_self()); 1003#else 1004 // thread_id is kernel thread id (similar to Solaris LWP id) 1005 osthread->set_thread_id(os::Bsd::gettid()); 1006 1007 if (UseNUMA) { 1008 int lgrp_id = os::numa_get_group_id(); 1009 if (lgrp_id != -1) { 1010 thread->set_lgrp_id(lgrp_id); 1011 } 1012 } 1013#endif 1014 // initialize signal mask for this thread 1015 os::Bsd::hotspot_sigmask(thread); 1016 1017 // initialize floating point control register 1018 os::Bsd::init_thread_fpu_state(); 1019 1020#ifdef __APPLE__ 1021 // register thread with objc gc 1022 if (objc_registerThreadWithCollectorFunction != NULL) { 1023 objc_registerThreadWithCollectorFunction(); 1024 } 1025#endif 1026 1027 // handshaking with parent thread 1028 { 1029 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); 1030 1031 // notify parent thread 1032 osthread->set_state(INITIALIZED); 1033 sync->notify_all(); 1034 1035 // wait until os::start_thread() 1036 while (osthread->get_state() == INITIALIZED) { 1037 sync->wait(Mutex::_no_safepoint_check_flag); 1038 } 1039 } 1040 1041 // call one more level start routine 1042 thread->run(); 1043 1044 return 0; 1045} 1046 1047bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { 1048 assert(thread->osthread() == NULL, "caller responsible"); 1049 1050 // Allocate the OSThread object 1051 OSThread* osthread = new OSThread(NULL, NULL); 1052 if (osthread == NULL) { 1053 return false; 1054 } 1055 1056 // set the correct thread state 1057 osthread->set_thread_type(thr_type); 1058 1059 // Initial state is ALLOCATED but not INITIALIZED 1060 osthread->set_state(ALLOCATED); 1061 1062 thread->set_osthread(osthread); 1063 1064 // init thread attributes 1065 pthread_attr_t attr; 1066 pthread_attr_init(&attr); 1067 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); 1068 1069 // stack size 1070 if (os::Bsd::supports_variable_stack_size()) { 1071 // calculate stack size if it's not specified by caller 1072 if (stack_size == 0) { 1073 stack_size = os::Bsd::default_stack_size(thr_type); 1074 1075 switch (thr_type) { 1076 case os::java_thread: 1077 // Java threads use ThreadStackSize which default value can be 1078 // changed with the flag -Xss 1079 assert (JavaThread::stack_size_at_create() > 0, "this should be set"); 1080 stack_size = JavaThread::stack_size_at_create(); 1081 break; 1082 case os::compiler_thread: 1083 if (CompilerThreadStackSize > 0) { 1084 stack_size = (size_t)(CompilerThreadStackSize * K); 1085 break; 1086 } // else fall through: 1087 // use VMThreadStackSize if CompilerThreadStackSize is not defined 1088 case os::vm_thread: 1089 case os::pgc_thread: 1090 case os::cgc_thread: 1091 case os::watcher_thread: 1092 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); 1093 break; 1094 } 1095 } 1096 1097 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); 1098 pthread_attr_setstacksize(&attr, stack_size); 1099 } else { 1100 // let pthread_create() pick the default value. 1101 } 1102 1103#ifndef _ALLBSD_SOURCE 1104 // glibc guard page 1105 pthread_attr_setguardsize(&attr, os::Bsd::default_guard_size(thr_type)); 1106#endif 1107 1108 ThreadState state; 1109 1110 { 1111 1112#ifndef _ALLBSD_SOURCE 1113 // Serialize thread creation if we are running with fixed stack BsdThreads 1114 bool lock = os::Bsd::is_BsdThreads() && !os::Bsd::is_floating_stack(); 1115 if (lock) { 1116 os::Bsd::createThread_lock()->lock_without_safepoint_check(); 1117 } 1118#endif 1119 1120 pthread_t tid; 1121 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); 1122 1123 pthread_attr_destroy(&attr); 1124 1125 if (ret != 0) { 1126 if (PrintMiscellaneous && (Verbose || WizardMode)) { 1127 perror("pthread_create()"); 1128 } 1129 // Need to clean up stuff we've allocated so far 1130 thread->set_osthread(NULL); 1131 delete osthread; 1132#ifndef _ALLBSD_SOURCE 1133 if (lock) os::Bsd::createThread_lock()->unlock(); 1134#endif 1135 return false; 1136 } 1137 1138 // Store pthread info into the OSThread 1139 osthread->set_pthread_id(tid); 1140 1141 // Wait until child thread is either initialized or aborted 1142 { 1143 Monitor* sync_with_child = osthread->startThread_lock(); 1144 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 1145 while ((state = osthread->get_state()) == ALLOCATED) { 1146 sync_with_child->wait(Mutex::_no_safepoint_check_flag); 1147 } 1148 } 1149 1150#ifndef _ALLBSD_SOURCE 1151 if (lock) { 1152 os::Bsd::createThread_lock()->unlock(); 1153 } 1154#endif 1155 } 1156 1157 // Aborted due to thread limit being reached 1158 if (state == ZOMBIE) { 1159 thread->set_osthread(NULL); 1160 delete osthread; 1161 return false; 1162 } 1163 1164 // The thread is returned suspended (in state INITIALIZED), 1165 // and is started higher up in the call chain 1166 assert(state == INITIALIZED, "race condition"); 1167 return true; 1168} 1169 1170///////////////////////////////////////////////////////////////////////////// 1171// attach existing thread 1172 1173// bootstrap the main thread 1174bool os::create_main_thread(JavaThread* thread) { 1175 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); 1176 return create_attached_thread(thread); 1177} 1178 1179bool os::create_attached_thread(JavaThread* thread) { 1180#ifdef ASSERT 1181 thread->verify_not_published(); 1182#endif 1183 1184 // Allocate the OSThread object 1185 OSThread* osthread = new OSThread(NULL, NULL); 1186 1187 if (osthread == NULL) { 1188 return false; 1189 } 1190 1191 // Store pthread info into the OSThread 1192#ifdef _ALLBSD_SOURCE 1193 osthread->set_thread_id(::pthread_self()); 1194#else 1195 osthread->set_thread_id(os::Bsd::gettid()); 1196#endif 1197 osthread->set_pthread_id(::pthread_self()); 1198 1199 // initialize floating point control register 1200 os::Bsd::init_thread_fpu_state(); 1201 1202 // Initial thread state is RUNNABLE 1203 osthread->set_state(RUNNABLE); 1204 1205 thread->set_osthread(osthread); 1206 1207#ifndef _ALLBSD_SOURCE 1208 if (UseNUMA) { 1209 int lgrp_id = os::numa_get_group_id(); 1210 if (lgrp_id != -1) { 1211 thread->set_lgrp_id(lgrp_id); 1212 } 1213 } 1214 1215 if (os::Bsd::is_initial_thread()) { 1216 // If current thread is initial thread, its stack is mapped on demand, 1217 // see notes about MAP_GROWSDOWN. Here we try to force kernel to map 1218 // the entire stack region to avoid SEGV in stack banging. 1219 // It is also useful to get around the heap-stack-gap problem on SuSE 1220 // kernel (see 4821821 for details). We first expand stack to the top 1221 // of yellow zone, then enable stack yellow zone (order is significant, 1222 // enabling yellow zone first will crash JVM on SuSE Bsd), so there 1223 // is no gap between the last two virtual memory regions. 1224 1225 JavaThread *jt = (JavaThread *)thread; 1226 address addr = jt->stack_yellow_zone_base(); 1227 assert(addr != NULL, "initialization problem?"); 1228 assert(jt->stack_available(addr) > 0, "stack guard should not be enabled"); 1229 1230 osthread->set_expanding_stack(); 1231 os::Bsd::manually_expand_stack(jt, addr); 1232 osthread->clear_expanding_stack(); 1233 } 1234#endif 1235 1236 // initialize signal mask for this thread 1237 // and save the caller's signal mask 1238 os::Bsd::hotspot_sigmask(thread); 1239 1240 return true; 1241} 1242 1243void os::pd_start_thread(Thread* thread) { 1244 OSThread * osthread = thread->osthread(); 1245 assert(osthread->get_state() != INITIALIZED, "just checking"); 1246 Monitor* sync_with_child = osthread->startThread_lock(); 1247 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); 1248 sync_with_child->notify(); 1249} 1250 1251// Free Bsd resources related to the OSThread 1252void os::free_thread(OSThread* osthread) { 1253 assert(osthread != NULL, "osthread not set"); 1254 1255 if (Thread::current()->osthread() == osthread) { 1256 // Restore caller's signal mask 1257 sigset_t sigmask = osthread->caller_sigmask(); 1258 pthread_sigmask(SIG_SETMASK, &sigmask, NULL); 1259 } 1260 1261 delete osthread; 1262} 1263 1264////////////////////////////////////////////////////////////////////////////// 1265// thread local storage 1266 1267int os::allocate_thread_local_storage() { 1268 pthread_key_t key; 1269 int rslt = pthread_key_create(&key, NULL); 1270 assert(rslt == 0, "cannot allocate thread local storage"); 1271 return (int)key; 1272} 1273 1274// Note: This is currently not used by VM, as we don't destroy TLS key 1275// on VM exit. 1276void os::free_thread_local_storage(int index) { 1277 int rslt = pthread_key_delete((pthread_key_t)index); 1278 assert(rslt == 0, "invalid index"); 1279} 1280 1281void os::thread_local_storage_at_put(int index, void* value) { 1282 int rslt = pthread_setspecific((pthread_key_t)index, value); 1283 assert(rslt == 0, "pthread_setspecific failed"); 1284} 1285 1286extern "C" Thread* get_thread() { 1287 return ThreadLocalStorage::thread(); 1288} 1289 1290////////////////////////////////////////////////////////////////////////////// 1291// initial thread 1292 1293#ifndef _ALLBSD_SOURCE 1294// Check if current thread is the initial thread, similar to Solaris thr_main. 1295bool os::Bsd::is_initial_thread(void) { 1296 char dummy; 1297 // If called before init complete, thread stack bottom will be null. 1298 // Can be called if fatal error occurs before initialization. 1299 if (initial_thread_stack_bottom() == NULL) return false; 1300 assert(initial_thread_stack_bottom() != NULL && 1301 initial_thread_stack_size() != 0, 1302 "os::init did not locate initial thread's stack region"); 1303 if ((address)&dummy >= initial_thread_stack_bottom() && 1304 (address)&dummy < initial_thread_stack_bottom() + initial_thread_stack_size()) 1305 return true; 1306 else return false; 1307} 1308 1309// Find the virtual memory area that contains addr 1310static bool find_vma(address addr, address* vma_low, address* vma_high) { 1311 FILE *fp = fopen("/proc/self/maps", "r"); 1312 if (fp) { 1313 address low, high; 1314 while (!feof(fp)) { 1315 if (fscanf(fp, "%p-%p", &low, &high) == 2) { 1316 if (low <= addr && addr < high) { 1317 if (vma_low) *vma_low = low; 1318 if (vma_high) *vma_high = high; 1319 fclose (fp); 1320 return true; 1321 } 1322 } 1323 for (;;) { 1324 int ch = fgetc(fp); 1325 if (ch == EOF || ch == (int)'\n') break; 1326 } 1327 } 1328 fclose(fp); 1329 } 1330 return false; 1331} 1332 1333// Locate initial thread stack. This special handling of initial thread stack 1334// is needed because pthread_getattr_np() on most (all?) Bsd distros returns 1335// bogus value for initial thread. 1336void os::Bsd::capture_initial_stack(size_t max_size) { 1337 // stack size is the easy part, get it from RLIMIT_STACK 1338 size_t stack_size; 1339 struct rlimit rlim; 1340 getrlimit(RLIMIT_STACK, &rlim); 1341 stack_size = rlim.rlim_cur; 1342 1343 // 6308388: a bug in ld.so will relocate its own .data section to the 1344 // lower end of primordial stack; reduce ulimit -s value a little bit 1345 // so we won't install guard page on ld.so's data section. 1346 stack_size -= 2 * page_size(); 1347 1348 // 4441425: avoid crash with "unlimited" stack size on SuSE 7.1 or Redhat 1349 // 7.1, in both cases we will get 2G in return value. 1350 // 4466587: glibc 2.2.x compiled w/o "--enable-kernel=2.4.0" (RH 7.0, 1351 // SuSE 7.2, Debian) can not handle alternate signal stack correctly 1352 // for initial thread if its stack size exceeds 6M. Cap it at 2M, 1353 // in case other parts in glibc still assumes 2M max stack size. 1354 // FIXME: alt signal stack is gone, maybe we can relax this constraint? 1355#ifndef IA64 1356 if (stack_size > 2 * K * K) stack_size = 2 * K * K; 1357#else 1358 // Problem still exists RH7.2 (IA64 anyway) but 2MB is a little small 1359 if (stack_size > 4 * K * K) stack_size = 4 * K * K; 1360#endif 1361 1362 // Try to figure out where the stack base (top) is. This is harder. 1363 // 1364 // When an application is started, glibc saves the initial stack pointer in 1365 // a global variable "__libc_stack_end", which is then used by system 1366 // libraries. __libc_stack_end should be pretty close to stack top. The 1367 // variable is available since the very early days. However, because it is 1368 // a private interface, it could disappear in the future. 1369 // 1370 // Bsd kernel saves start_stack information in /proc/<pid>/stat. Similar 1371 // to __libc_stack_end, it is very close to stack top, but isn't the real 1372 // stack top. Note that /proc may not exist if VM is running as a chroot 1373 // program, so reading /proc/<pid>/stat could fail. Also the contents of 1374 // /proc/<pid>/stat could change in the future (though unlikely). 1375 // 1376 // We try __libc_stack_end first. If that doesn't work, look for 1377 // /proc/<pid>/stat. If neither of them works, we use current stack pointer 1378 // as a hint, which should work well in most cases. 1379 1380 uintptr_t stack_start; 1381 1382 // try __libc_stack_end first 1383 uintptr_t *p = (uintptr_t *)dlsym(RTLD_DEFAULT, "__libc_stack_end"); 1384 if (p && *p) { 1385 stack_start = *p; 1386 } else { 1387 // see if we can get the start_stack field from /proc/self/stat 1388 FILE *fp; 1389 int pid; 1390 char state; 1391 int ppid; 1392 int pgrp; 1393 int session; 1394 int nr; 1395 int tpgrp; 1396 unsigned long flags; 1397 unsigned long minflt; 1398 unsigned long cminflt; 1399 unsigned long majflt; 1400 unsigned long cmajflt; 1401 unsigned long utime; 1402 unsigned long stime; 1403 long cutime; 1404 long cstime; 1405 long prio; 1406 long nice; 1407 long junk; 1408 long it_real; 1409 uintptr_t start; 1410 uintptr_t vsize; 1411 intptr_t rss; 1412 uintptr_t rsslim; 1413 uintptr_t scodes; 1414 uintptr_t ecode; 1415 int i; 1416 1417 // Figure what the primordial thread stack base is. Code is inspired 1418 // by email from Hans Boehm. /proc/self/stat begins with current pid, 1419 // followed by command name surrounded by parentheses, state, etc. 1420 char stat[2048]; 1421 int statlen; 1422 1423 fp = fopen("/proc/self/stat", "r"); 1424 if (fp) { 1425 statlen = fread(stat, 1, 2047, fp); 1426 stat[statlen] = '\0'; 1427 fclose(fp); 1428 1429 // Skip pid and the command string. Note that we could be dealing with 1430 // weird command names, e.g. user could decide to rename java launcher 1431 // to "java 1.4.2 :)", then the stat file would look like 1432 // 1234 (java 1.4.2 :)) R ... ... 1433 // We don't really need to know the command string, just find the last 1434 // occurrence of ")" and then start parsing from there. See bug 4726580. 1435 char * s = strrchr(stat, ')'); 1436 1437 i = 0; 1438 if (s) { 1439 // Skip blank chars 1440 do s++; while (isspace(*s)); 1441 1442#define _UFM UINTX_FORMAT 1443#define _DFM INTX_FORMAT 1444 1445 /* 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 */ 1446 /* 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 */ 1447 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, 1448 &state, /* 3 %c */ 1449 &ppid, /* 4 %d */ 1450 &pgrp, /* 5 %d */ 1451 &session, /* 6 %d */ 1452 &nr, /* 7 %d */ 1453 &tpgrp, /* 8 %d */ 1454 &flags, /* 9 %lu */ 1455 &minflt, /* 10 %lu */ 1456 &cminflt, /* 11 %lu */ 1457 &majflt, /* 12 %lu */ 1458 &cmajflt, /* 13 %lu */ 1459 &utime, /* 14 %lu */ 1460 &stime, /* 15 %lu */ 1461 &cutime, /* 16 %ld */ 1462 &cstime, /* 17 %ld */ 1463 &prio, /* 18 %ld */ 1464 &nice, /* 19 %ld */ 1465 &junk, /* 20 %ld */ 1466 &it_real, /* 21 %ld */ 1467 &start, /* 22 UINTX_FORMAT */ 1468 &vsize, /* 23 UINTX_FORMAT */ 1469 &rss, /* 24 INTX_FORMAT */ 1470 &rsslim, /* 25 UINTX_FORMAT */ 1471 &scodes, /* 26 UINTX_FORMAT */ 1472 &ecode, /* 27 UINTX_FORMAT */ 1473 &stack_start); /* 28 UINTX_FORMAT */ 1474 } 1475 1476#undef _UFM 1477#undef _DFM 1478 1479 if (i != 28 - 2) { 1480 assert(false, "Bad conversion from /proc/self/stat"); 1481 // product mode - assume we are the initial thread, good luck in the 1482 // embedded case. 1483 warning("Can't detect initial thread stack location - bad conversion"); 1484 stack_start = (uintptr_t) &rlim; 1485 } 1486 } else { 1487 // For some reason we can't open /proc/self/stat (for example, running on 1488 // FreeBSD with a Bsd emulator, or inside chroot), this should work for 1489 // most cases, so don't abort: 1490 warning("Can't detect initial thread stack location - no /proc/self/stat"); 1491 stack_start = (uintptr_t) &rlim; 1492 } 1493 } 1494 1495 // Now we have a pointer (stack_start) very close to the stack top, the 1496 // next thing to do is to figure out the exact location of stack top. We 1497 // can find out the virtual memory area that contains stack_start by 1498 // reading /proc/self/maps, it should be the last vma in /proc/self/maps, 1499 // and its upper limit is the real stack top. (again, this would fail if 1500 // running inside chroot, because /proc may not exist.) 1501 1502 uintptr_t stack_top; 1503 address low, high; 1504 if (find_vma((address)stack_start, &low, &high)) { 1505 // success, "high" is the true stack top. (ignore "low", because initial 1506 // thread stack grows on demand, its real bottom is high - RLIMIT_STACK.) 1507 stack_top = (uintptr_t)high; 1508 } else { 1509 // failed, likely because /proc/self/maps does not exist 1510 warning("Can't detect initial thread stack location - find_vma failed"); 1511 // best effort: stack_start is normally within a few pages below the real 1512 // stack top, use it as stack top, and reduce stack size so we won't put 1513 // guard page outside stack. 1514 stack_top = stack_start; 1515 stack_size -= 16 * page_size(); 1516 } 1517 1518 // stack_top could be partially down the page so align it 1519 stack_top = align_size_up(stack_top, page_size()); 1520 1521 if (max_size && stack_size > max_size) { 1522 _initial_thread_stack_size = max_size; 1523 } else { 1524 _initial_thread_stack_size = stack_size; 1525 } 1526 1527 _initial_thread_stack_size = align_size_down(_initial_thread_stack_size, page_size()); 1528 _initial_thread_stack_bottom = (address)stack_top - _initial_thread_stack_size; 1529} 1530#endif 1531 1532//////////////////////////////////////////////////////////////////////////////// 1533// time support 1534 1535// Time since start-up in seconds to a fine granularity. 1536// Used by VMSelfDestructTimer and the MemProfiler. 1537double os::elapsedTime() { 1538 1539 return (double)(os::elapsed_counter()) * 0.000001; 1540} 1541 1542jlong os::elapsed_counter() { 1543 timeval time; 1544 int status = gettimeofday(&time, NULL); 1545 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count; 1546} 1547 1548jlong os::elapsed_frequency() { 1549 return (1000 * 1000); 1550} 1551 1552// XXX: For now, code this as if BSD does not support vtime. 1553bool os::supports_vtime() { return false; } 1554bool os::enable_vtime() { return false; } 1555bool os::vtime_enabled() { return false; } 1556double os::elapsedVTime() { 1557 // better than nothing, but not much 1558 return elapsedTime(); 1559} 1560 1561jlong os::javaTimeMillis() { 1562 timeval time; 1563 int status = gettimeofday(&time, NULL); 1564 assert(status != -1, "bsd error"); 1565 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); 1566} 1567 1568#ifndef CLOCK_MONOTONIC 1569#define CLOCK_MONOTONIC (1) 1570#endif 1571 1572#ifdef __APPLE__ 1573void os::Bsd::clock_init() { 1574 // XXXDARWIN: Investigate replacement monotonic clock 1575} 1576#elif defined(_ALLBSD_SOURCE) 1577void os::Bsd::clock_init() { 1578 struct timespec res; 1579 struct timespec tp; 1580 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && 1581 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { 1582 // yes, monotonic clock is supported 1583 _clock_gettime = ::clock_gettime; 1584 } 1585} 1586#else 1587void os::Bsd::clock_init() { 1588 // we do dlopen's in this particular order due to bug in bsd 1589 // dynamical loader (see 6348968) leading to crash on exit 1590 void* handle = dlopen("librt.so.1", RTLD_LAZY); 1591 if (handle == NULL) { 1592 handle = dlopen("librt.so", RTLD_LAZY); 1593 } 1594 1595 if (handle) { 1596 int (*clock_getres_func)(clockid_t, struct timespec*) = 1597 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_getres"); 1598 int (*clock_gettime_func)(clockid_t, struct timespec*) = 1599 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_gettime"); 1600 if (clock_getres_func && clock_gettime_func) { 1601 // See if monotonic clock is supported by the kernel. Note that some 1602 // early implementations simply return kernel jiffies (updated every 1603 // 1/100 or 1/1000 second). It would be bad to use such a low res clock 1604 // for nano time (though the monotonic property is still nice to have). 1605 // It's fixed in newer kernels, however clock_getres() still returns 1606 // 1/HZ. We check if clock_getres() works, but will ignore its reported 1607 // resolution for now. Hopefully as people move to new kernels, this 1608 // won't be a problem. 1609 struct timespec res; 1610 struct timespec tp; 1611 if (clock_getres_func (CLOCK_MONOTONIC, &res) == 0 && 1612 clock_gettime_func(CLOCK_MONOTONIC, &tp) == 0) { 1613 // yes, monotonic clock is supported 1614 _clock_gettime = clock_gettime_func; 1615 } else { 1616 // close librt if there is no monotonic clock 1617 dlclose(handle); 1618 } 1619 } 1620 } 1621} 1622#endif 1623 1624#ifndef _ALLBSD_SOURCE 1625#ifndef SYS_clock_getres 1626 1627#if defined(IA32) || defined(AMD64) 1628#define SYS_clock_getres IA32_ONLY(266) AMD64_ONLY(229) 1629#define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y) 1630#else 1631#warning "SYS_clock_getres not defined for this platform, disabling fast_thread_cpu_time" 1632#define sys_clock_getres(x,y) -1 1633#endif 1634 1635#else 1636#define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y) 1637#endif 1638 1639void os::Bsd::fast_thread_clock_init() { 1640 if (!UseBsdPosixThreadCPUClocks) { 1641 return; 1642 } 1643 clockid_t clockid; 1644 struct timespec tp; 1645 int (*pthread_getcpuclockid_func)(pthread_t, clockid_t *) = 1646 (int(*)(pthread_t, clockid_t *)) dlsym(RTLD_DEFAULT, "pthread_getcpuclockid"); 1647 1648 // Switch to using fast clocks for thread cpu time if 1649 // the sys_clock_getres() returns 0 error code. 1650 // Note, that some kernels may support the current thread 1651 // clock (CLOCK_THREAD_CPUTIME_ID) but not the clocks 1652 // returned by the pthread_getcpuclockid(). 1653 // If the fast Posix clocks are supported then the sys_clock_getres() 1654 // must return at least tp.tv_sec == 0 which means a resolution 1655 // better than 1 sec. This is extra check for reliability. 1656 1657 if(pthread_getcpuclockid_func && 1658 pthread_getcpuclockid_func(_main_thread, &clockid) == 0 && 1659 sys_clock_getres(clockid, &tp) == 0 && tp.tv_sec == 0) { 1660 1661 _supports_fast_thread_cpu_time = true; 1662 _pthread_getcpuclockid = pthread_getcpuclockid_func; 1663 } 1664} 1665#endif 1666 1667jlong os::javaTimeNanos() { 1668 if (Bsd::supports_monotonic_clock()) { 1669 struct timespec tp; 1670 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp); 1671 assert(status == 0, "gettime error"); 1672 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); 1673 return result; 1674 } else { 1675 timeval time; 1676 int status = gettimeofday(&time, NULL); 1677 assert(status != -1, "bsd error"); 1678 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); 1679 return 1000 * usecs; 1680 } 1681} 1682 1683void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { 1684 if (Bsd::supports_monotonic_clock()) { 1685 info_ptr->max_value = ALL_64_BITS; 1686 1687 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past 1688 info_ptr->may_skip_backward = false; // not subject to resetting or drifting 1689 info_ptr->may_skip_forward = false; // not subject to resetting or drifting 1690 } else { 1691 // gettimeofday - based on time in seconds since the Epoch thus does not wrap 1692 info_ptr->max_value = ALL_64_BITS; 1693 1694 // gettimeofday is a real time clock so it skips 1695 info_ptr->may_skip_backward = true; 1696 info_ptr->may_skip_forward = true; 1697 } 1698 1699 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time 1700} 1701 1702// Return the real, user, and system times in seconds from an 1703// arbitrary fixed point in the past. 1704bool os::getTimesSecs(double* process_real_time, 1705 double* process_user_time, 1706 double* process_system_time) { 1707 struct tms ticks; 1708 clock_t real_ticks = times(&ticks); 1709 1710 if (real_ticks == (clock_t) (-1)) { 1711 return false; 1712 } else { 1713 double ticks_per_second = (double) clock_tics_per_sec; 1714 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; 1715 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; 1716 *process_real_time = ((double) real_ticks) / ticks_per_second; 1717 1718 return true; 1719 } 1720} 1721 1722 1723char * os::local_time_string(char *buf, size_t buflen) { 1724 struct tm t; 1725 time_t long_time; 1726 time(&long_time); 1727 localtime_r(&long_time, &t); 1728 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", 1729 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, 1730 t.tm_hour, t.tm_min, t.tm_sec); 1731 return buf; 1732} 1733 1734struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { 1735 return localtime_r(clock, res); 1736} 1737 1738//////////////////////////////////////////////////////////////////////////////// 1739// runtime exit support 1740 1741// Note: os::shutdown() might be called very early during initialization, or 1742// called from signal handler. Before adding something to os::shutdown(), make 1743// sure it is async-safe and can handle partially initialized VM. 1744void os::shutdown() { 1745 1746 // allow PerfMemory to attempt cleanup of any persistent resources 1747 perfMemory_exit(); 1748 1749 // needs to remove object in file system 1750 AttachListener::abort(); 1751 1752 // flush buffered output, finish log files 1753 ostream_abort(); 1754 1755 // Check for abort hook 1756 abort_hook_t abort_hook = Arguments::abort_hook(); 1757 if (abort_hook != NULL) { 1758 abort_hook(); 1759 } 1760 1761} 1762 1763// Note: os::abort() might be called very early during initialization, or 1764// called from signal handler. Before adding something to os::abort(), make 1765// sure it is async-safe and can handle partially initialized VM. 1766void os::abort(bool dump_core) { 1767 os::shutdown(); 1768 if (dump_core) { 1769#ifndef PRODUCT 1770 fdStream out(defaultStream::output_fd()); 1771 out.print_raw("Current thread is "); 1772 char buf[16]; 1773 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); 1774 out.print_raw_cr(buf); 1775 out.print_raw_cr("Dumping core ..."); 1776#endif 1777 ::abort(); // dump core 1778 } 1779 1780 ::exit(1); 1781} 1782 1783// Die immediately, no exit hook, no abort hook, no cleanup. 1784void os::die() { 1785 // _exit() on BsdThreads only kills current thread 1786 ::abort(); 1787} 1788 1789// unused on bsd for now. 1790void os::set_error_file(const char *logfile) {} 1791 1792 1793// This method is a copy of JDK's sysGetLastErrorString 1794// from src/solaris/hpi/src/system_md.c 1795 1796size_t os::lasterror(char *buf, size_t len) { 1797 1798 if (errno == 0) return 0; 1799 1800 const char *s = ::strerror(errno); 1801 size_t n = ::strlen(s); 1802 if (n >= len) { 1803 n = len - 1; 1804 } 1805 ::strncpy(buf, s, n); 1806 buf[n] = '\0'; 1807 return n; 1808} 1809 1810intx os::current_thread_id() { return (intx)pthread_self(); } 1811int os::current_process_id() { 1812 1813 // Under the old bsd thread library, bsd gives each thread 1814 // its own process id. Because of this each thread will return 1815 // a different pid if this method were to return the result 1816 // of getpid(2). Bsd provides no api that returns the pid 1817 // of the launcher thread for the vm. This implementation 1818 // returns a unique pid, the pid of the launcher thread 1819 // that starts the vm 'process'. 1820 1821 // Under the NPTL, getpid() returns the same pid as the 1822 // launcher thread rather than a unique pid per thread. 1823 // Use gettid() if you want the old pre NPTL behaviour. 1824 1825 // if you are looking for the result of a call to getpid() that 1826 // returns a unique pid for the calling thread, then look at the 1827 // OSThread::thread_id() method in osThread_bsd.hpp file 1828 1829 return (int)(_initial_pid ? _initial_pid : getpid()); 1830} 1831 1832// DLL functions 1833 1834#define JNI_LIB_PREFIX "lib" 1835#ifdef __APPLE__ 1836#define JNI_LIB_SUFFIX ".dylib" 1837#else 1838#define JNI_LIB_SUFFIX ".so" 1839#endif 1840 1841const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } 1842 1843// This must be hard coded because it's the system's temporary 1844// directory not the java application's temp directory, ala java.io.tmpdir. 1845#ifdef __APPLE__ 1846// macosx has a secure per-user temporary directory 1847char temp_path_storage[PATH_MAX]; 1848const char* os::get_temp_directory() { 1849 static char *temp_path = NULL; 1850 if (temp_path == NULL) { 1851 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); 1852 if (pathSize == 0 || pathSize > PATH_MAX) { 1853 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); 1854 } 1855 temp_path = temp_path_storage; 1856 } 1857 return temp_path; 1858} 1859#else /* __APPLE__ */ 1860const char* os::get_temp_directory() { return "/tmp"; } 1861#endif /* __APPLE__ */ 1862 1863static bool file_exists(const char* filename) { 1864 struct stat statbuf; 1865 if (filename == NULL || strlen(filename) == 0) { 1866 return false; 1867 } 1868 return os::stat(filename, &statbuf) == 0; 1869} 1870 1871void os::dll_build_name(char* buffer, size_t buflen, 1872 const char* pname, const char* fname) { 1873 // Copied from libhpi 1874 const size_t pnamelen = pname ? strlen(pname) : 0; 1875 1876 // Quietly truncate on buffer overflow. Should be an error. 1877 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { 1878 *buffer = '\0'; 1879 return; 1880 } 1881 1882 if (pnamelen == 0) { 1883 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); 1884 } else if (strchr(pname, *os::path_separator()) != NULL) { 1885 int n; 1886 char** pelements = split_path(pname, &n); 1887 for (int i = 0 ; i < n ; i++) { 1888 // Really shouldn't be NULL, but check can't hurt 1889 if (pelements[i] == NULL || strlen(pelements[i]) == 0) { 1890 continue; // skip the empty path values 1891 } 1892 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, 1893 pelements[i], fname); 1894 if (file_exists(buffer)) { 1895 break; 1896 } 1897 } 1898 // release the storage 1899 for (int i = 0 ; i < n ; i++) { 1900 if (pelements[i] != NULL) { 1901 FREE_C_HEAP_ARRAY(char, pelements[i]); 1902 } 1903 } 1904 if (pelements != NULL) { 1905 FREE_C_HEAP_ARRAY(char*, pelements); 1906 } 1907 } else { 1908 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); 1909 } 1910} 1911 1912const char* os::get_current_directory(char *buf, int buflen) { 1913 return getcwd(buf, buflen); 1914} 1915 1916// check if addr is inside libjvm[_g].so 1917bool os::address_is_in_vm(address addr) { 1918 static address libjvm_base_addr; 1919 Dl_info dlinfo; 1920 1921 if (libjvm_base_addr == NULL) { 1922 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo); 1923 libjvm_base_addr = (address)dlinfo.dli_fbase; 1924 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); 1925 } 1926 1927 if (dladdr((void *)addr, &dlinfo)) { 1928 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; 1929 } 1930 1931 return false; 1932} 1933 1934bool os::dll_address_to_function_name(address addr, char *buf, 1935 int buflen, int *offset) { 1936 Dl_info dlinfo; 1937 1938 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) { 1939 if (buf != NULL) { 1940 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { 1941 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); 1942 } 1943 } 1944 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; 1945 return true; 1946 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) { 1947 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), 1948 buf, buflen, offset, dlinfo.dli_fname)) { 1949 return true; 1950 } 1951 } 1952 1953 if (buf != NULL) buf[0] = '\0'; 1954 if (offset != NULL) *offset = -1; 1955 return false; 1956} 1957 1958#ifdef _ALLBSD_SOURCE 1959// ported from solaris version 1960bool os::dll_address_to_library_name(address addr, char* buf, 1961 int buflen, int* offset) { 1962 Dl_info dlinfo; 1963 1964 if (dladdr((void*)addr, &dlinfo)){ 1965 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 1966 if (offset) *offset = addr - (address)dlinfo.dli_fbase; 1967 return true; 1968 } else { 1969 if (buf) buf[0] = '\0'; 1970 if (offset) *offset = -1; 1971 return false; 1972 } 1973} 1974#else 1975struct _address_to_library_name { 1976 address addr; // input : memory address 1977 size_t buflen; // size of fname 1978 char* fname; // output: library name 1979 address base; // library base addr 1980}; 1981 1982static int address_to_library_name_callback(struct dl_phdr_info *info, 1983 size_t size, void *data) { 1984 int i; 1985 bool found = false; 1986 address libbase = NULL; 1987 struct _address_to_library_name * d = (struct _address_to_library_name *)data; 1988 1989 // iterate through all loadable segments 1990 for (i = 0; i < info->dlpi_phnum; i++) { 1991 address segbase = (address)(info->dlpi_addr + info->dlpi_phdr[i].p_vaddr); 1992 if (info->dlpi_phdr[i].p_type == PT_LOAD) { 1993 // base address of a library is the lowest address of its loaded 1994 // segments. 1995 if (libbase == NULL || libbase > segbase) { 1996 libbase = segbase; 1997 } 1998 // see if 'addr' is within current segment 1999 if (segbase <= d->addr && 2000 d->addr < segbase + info->dlpi_phdr[i].p_memsz) { 2001 found = true; 2002 } 2003 } 2004 } 2005 2006 // dlpi_name is NULL or empty if the ELF file is executable, return 0 2007 // so dll_address_to_library_name() can fall through to use dladdr() which 2008 // can figure out executable name from argv[0]. 2009 if (found && info->dlpi_name && info->dlpi_name[0]) { 2010 d->base = libbase; 2011 if (d->fname) { 2012 jio_snprintf(d->fname, d->buflen, "%s", info->dlpi_name); 2013 } 2014 return 1; 2015 } 2016 return 0; 2017} 2018 2019bool os::dll_address_to_library_name(address addr, char* buf, 2020 int buflen, int* offset) { 2021 Dl_info dlinfo; 2022 struct _address_to_library_name data; 2023 2024 // There is a bug in old glibc dladdr() implementation that it could resolve 2025 // to wrong library name if the .so file has a base address != NULL. Here 2026 // we iterate through the program headers of all loaded libraries to find 2027 // out which library 'addr' really belongs to. This workaround can be 2028 // removed once the minimum requirement for glibc is moved to 2.3.x. 2029 data.addr = addr; 2030 data.fname = buf; 2031 data.buflen = buflen; 2032 data.base = NULL; 2033 int rslt = dl_iterate_phdr(address_to_library_name_callback, (void *)&data); 2034 2035 if (rslt) { 2036 // buf already contains library name 2037 if (offset) *offset = addr - data.base; 2038 return true; 2039 } else if (dladdr((void*)addr, &dlinfo)){ 2040 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); 2041 if (offset) *offset = addr - (address)dlinfo.dli_fbase; 2042 return true; 2043 } else { 2044 if (buf) buf[0] = '\0'; 2045 if (offset) *offset = -1; 2046 return false; 2047 } 2048} 2049#endif 2050 2051 // Loads .dll/.so and 2052 // in case of error it checks if .dll/.so was built for the 2053 // same architecture as Hotspot is running on 2054 2055#ifdef __APPLE__ 2056void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { 2057 void * result= ::dlopen(filename, RTLD_LAZY); 2058 if (result != NULL) { 2059 // Successful loading 2060 return result; 2061 } 2062 2063 // Read system error message into ebuf 2064 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 2065 ebuf[ebuflen-1]='\0'; 2066 2067 return NULL; 2068} 2069#else 2070void * os::dll_load(const char *filename, char *ebuf, int ebuflen) 2071{ 2072 void * result= ::dlopen(filename, RTLD_LAZY); 2073 if (result != NULL) { 2074 // Successful loading 2075 return result; 2076 } 2077 2078 Elf32_Ehdr elf_head; 2079 2080 // Read system error message into ebuf 2081 // It may or may not be overwritten below 2082 ::strncpy(ebuf, ::dlerror(), ebuflen-1); 2083 ebuf[ebuflen-1]='\0'; 2084 int diag_msg_max_length=ebuflen-strlen(ebuf); 2085 char* diag_msg_buf=ebuf+strlen(ebuf); 2086 2087 if (diag_msg_max_length==0) { 2088 // No more space in ebuf for additional diagnostics message 2089 return NULL; 2090 } 2091 2092 2093 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); 2094 2095 if (file_descriptor < 0) { 2096 // Can't open library, report dlerror() message 2097 return NULL; 2098 } 2099 2100 bool failed_to_read_elf_head= 2101 (sizeof(elf_head)!= 2102 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ; 2103 2104 ::close(file_descriptor); 2105 if (failed_to_read_elf_head) { 2106 // file i/o error - report dlerror() msg 2107 return NULL; 2108 } 2109 2110 typedef struct { 2111 Elf32_Half code; // Actual value as defined in elf.h 2112 Elf32_Half compat_class; // Compatibility of archs at VM's sense 2113 char elf_class; // 32 or 64 bit 2114 char endianess; // MSB or LSB 2115 char* name; // String representation 2116 } arch_t; 2117 2118 #ifndef EM_486 2119 #define EM_486 6 /* Intel 80486 */ 2120 #endif 2121 2122 #ifndef EM_MIPS_RS3_LE 2123 #define EM_MIPS_RS3_LE 10 /* MIPS */ 2124 #endif 2125 2126 #ifndef EM_PPC64 2127 #define EM_PPC64 21 /* PowerPC64 */ 2128 #endif 2129 2130 #ifndef EM_S390 2131 #define EM_S390 22 /* IBM System/390 */ 2132 #endif 2133 2134 #ifndef EM_IA_64 2135 #define EM_IA_64 50 /* HP/Intel IA-64 */ 2136 #endif 2137 2138 #ifndef EM_X86_64 2139 #define EM_X86_64 62 /* AMD x86-64 */ 2140 #endif 2141 2142 static const arch_t arch_array[]={ 2143 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 2144 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, 2145 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, 2146 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, 2147 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 2148 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, 2149 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, 2150 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, 2151 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, 2152 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, 2153 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, 2154 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, 2155 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, 2156 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, 2157 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, 2158 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} 2159 }; 2160 2161 #if (defined IA32) 2162 static Elf32_Half running_arch_code=EM_386; 2163 #elif (defined AMD64) 2164 static Elf32_Half running_arch_code=EM_X86_64; 2165 #elif (defined IA64) 2166 static Elf32_Half running_arch_code=EM_IA_64; 2167 #elif (defined __sparc) && (defined _LP64) 2168 static Elf32_Half running_arch_code=EM_SPARCV9; 2169 #elif (defined __sparc) && (!defined _LP64) 2170 static Elf32_Half running_arch_code=EM_SPARC; 2171 #elif (defined __powerpc64__) 2172 static Elf32_Half running_arch_code=EM_PPC64; 2173 #elif (defined __powerpc__) 2174 static Elf32_Half running_arch_code=EM_PPC; 2175 #elif (defined ARM) 2176 static Elf32_Half running_arch_code=EM_ARM; 2177 #elif (defined S390) 2178 static Elf32_Half running_arch_code=EM_S390; 2179 #elif (defined ALPHA) 2180 static Elf32_Half running_arch_code=EM_ALPHA; 2181 #elif (defined MIPSEL) 2182 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; 2183 #elif (defined PARISC) 2184 static Elf32_Half running_arch_code=EM_PARISC; 2185 #elif (defined MIPS) 2186 static Elf32_Half running_arch_code=EM_MIPS; 2187 #elif (defined M68K) 2188 static Elf32_Half running_arch_code=EM_68K; 2189 #else 2190 #error Method os::dll_load requires that one of following is defined:\ 2191 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K 2192 #endif 2193 2194 // Identify compatability class for VM's architecture and library's architecture 2195 // Obtain string descriptions for architectures 2196 2197 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; 2198 int running_arch_index=-1; 2199 2200 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) { 2201 if (running_arch_code == arch_array[i].code) { 2202 running_arch_index = i; 2203 } 2204 if (lib_arch.code == arch_array[i].code) { 2205 lib_arch.compat_class = arch_array[i].compat_class; 2206 lib_arch.name = arch_array[i].name; 2207 } 2208 } 2209 2210 assert(running_arch_index != -1, 2211 "Didn't find running architecture code (running_arch_code) in arch_array"); 2212 if (running_arch_index == -1) { 2213 // Even though running architecture detection failed 2214 // we may still continue with reporting dlerror() message 2215 return NULL; 2216 } 2217 2218 if (lib_arch.endianess != arch_array[running_arch_index].endianess) { 2219 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); 2220 return NULL; 2221 } 2222 2223#ifndef S390 2224 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { 2225 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); 2226 return NULL; 2227 } 2228#endif // !S390 2229 2230 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { 2231 if ( lib_arch.name!=NULL ) { 2232 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 2233 " (Possible cause: can't load %s-bit .so on a %s-bit platform)", 2234 lib_arch.name, arch_array[running_arch_index].name); 2235 } else { 2236 ::snprintf(diag_msg_buf, diag_msg_max_length-1, 2237 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", 2238 lib_arch.code, 2239 arch_array[running_arch_index].name); 2240 } 2241 } 2242 2243 return NULL; 2244} 2245#endif /* !__APPLE__ */ 2246 2247// XXX: Do we need a lock around this as per Linux? 2248void* os::dll_lookup(void* handle, const char* name) { 2249 return dlsym(handle, name); 2250} 2251 2252 2253static bool _print_ascii_file(const char* filename, outputStream* st) { 2254 int fd = ::open(filename, O_RDONLY); 2255 if (fd == -1) { 2256 return false; 2257 } 2258 2259 char buf[32]; 2260 int bytes; 2261 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { 2262 st->print_raw(buf, bytes); 2263 } 2264 2265 ::close(fd); 2266 2267 return true; 2268} 2269 2270void os::print_dll_info(outputStream *st) { 2271 st->print_cr("Dynamic libraries:"); 2272#ifdef _ALLBSD_SOURCE 2273#ifdef RTLD_DI_LINKMAP 2274 Dl_info dli; 2275 void *handle; 2276 Link_map *map; 2277 Link_map *p; 2278 2279 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) { 2280 st->print_cr("Error: Cannot print dynamic libraries."); 2281 return; 2282 } 2283 handle = dlopen(dli.dli_fname, RTLD_LAZY); 2284 if (handle == NULL) { 2285 st->print_cr("Error: Cannot print dynamic libraries."); 2286 return; 2287 } 2288 dlinfo(handle, RTLD_DI_LINKMAP, &map); 2289 if (map == NULL) { 2290 st->print_cr("Error: Cannot print dynamic libraries."); 2291 return; 2292 } 2293 2294 while (map->l_prev != NULL) 2295 map = map->l_prev; 2296 2297 while (map != NULL) { 2298 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); 2299 map = map->l_next; 2300 } 2301 2302 dlclose(handle); 2303#elif defined(__APPLE__) 2304 uint32_t count; 2305 uint32_t i; 2306 2307 count = _dyld_image_count(); 2308 for (i = 1; i < count; i++) { 2309 const char *name = _dyld_get_image_name(i); 2310 intptr_t slide = _dyld_get_image_vmaddr_slide(i); 2311 st->print_cr(PTR_FORMAT " \t%s", slide, name); 2312 } 2313#else 2314 st->print_cr("Error: Cannot print dynamic libraries."); 2315#endif 2316#else 2317 char fname[32]; 2318 pid_t pid = os::Bsd::gettid(); 2319 2320 jio_snprintf(fname, sizeof(fname), "/proc/%d/maps", pid); 2321 2322 if (!_print_ascii_file(fname, st)) { 2323 st->print("Can not get library information for pid = %d\n", pid); 2324 } 2325#endif 2326} 2327 2328 2329void os::print_os_info(outputStream* st) { 2330 st->print("OS:"); 2331 2332 // Try to identify popular distros. 2333 // Most Bsd distributions have /etc/XXX-release file, which contains 2334 // the OS version string. Some have more than one /etc/XXX-release file 2335 // (e.g. Mandrake has both /etc/mandrake-release and /etc/redhat-release.), 2336 // so the order is important. 2337 if (!_print_ascii_file("/etc/mandrake-release", st) && 2338 !_print_ascii_file("/etc/sun-release", st) && 2339 !_print_ascii_file("/etc/redhat-release", st) && 2340 !_print_ascii_file("/etc/SuSE-release", st) && 2341 !_print_ascii_file("/etc/turbobsd-release", st) && 2342 !_print_ascii_file("/etc/gentoo-release", st) && 2343 !_print_ascii_file("/etc/debian_version", st) && 2344 !_print_ascii_file("/etc/ltib-release", st) && 2345 !_print_ascii_file("/etc/angstrom-version", st)) { 2346 st->print("Bsd"); 2347 } 2348 st->cr(); 2349 2350 // kernel 2351 st->print("uname:"); 2352 struct utsname name; 2353 uname(&name); 2354 st->print(name.sysname); st->print(" "); 2355 st->print(name.release); st->print(" "); 2356 st->print(name.version); st->print(" "); 2357 st->print(name.machine); 2358 st->cr(); 2359 2360#ifndef _ALLBSD_SOURCE 2361 // Print warning if unsafe chroot environment detected 2362 if (unsafe_chroot_detected) { 2363 st->print("WARNING!! "); 2364 st->print_cr(unstable_chroot_error); 2365 } 2366 2367 // libc, pthread 2368 st->print("libc:"); 2369 st->print(os::Bsd::glibc_version()); st->print(" "); 2370 st->print(os::Bsd::libpthread_version()); st->print(" "); 2371 if (os::Bsd::is_BsdThreads()) { 2372 st->print("(%s stack)", os::Bsd::is_floating_stack() ? "floating" : "fixed"); 2373 } 2374 st->cr(); 2375#endif 2376 2377 // rlimit 2378 st->print("rlimit:"); 2379 struct rlimit rlim; 2380 2381 st->print(" STACK "); 2382 getrlimit(RLIMIT_STACK, &rlim); 2383 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2384 else st->print("%uk", rlim.rlim_cur >> 10); 2385 2386 st->print(", CORE "); 2387 getrlimit(RLIMIT_CORE, &rlim); 2388 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2389 else st->print("%uk", rlim.rlim_cur >> 10); 2390 2391 st->print(", NPROC "); 2392 getrlimit(RLIMIT_NPROC, &rlim); 2393 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2394 else st->print("%d", rlim.rlim_cur); 2395 2396 st->print(", NOFILE "); 2397 getrlimit(RLIMIT_NOFILE, &rlim); 2398 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2399 else st->print("%d", rlim.rlim_cur); 2400 2401#ifndef _ALLBSD_SOURCE 2402 st->print(", AS "); 2403 getrlimit(RLIMIT_AS, &rlim); 2404 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 2405 else st->print("%uk", rlim.rlim_cur >> 10); 2406 st->cr(); 2407 2408 // load average 2409 st->print("load average:"); 2410 double loadavg[3]; 2411 os::loadavg(loadavg, 3); 2412 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]); 2413 st->cr(); 2414#endif 2415} 2416 2417void os::pd_print_cpu_info(outputStream* st) { 2418 // Nothing to do for now. 2419} 2420 2421void os::print_memory_info(outputStream* st) { 2422 2423 st->print("Memory:"); 2424 st->print(" %dk page", os::vm_page_size()>>10); 2425 2426#ifndef _ALLBSD_SOURCE 2427 // values in struct sysinfo are "unsigned long" 2428 struct sysinfo si; 2429 sysinfo(&si); 2430#endif 2431 2432 st->print(", physical " UINT64_FORMAT "k", 2433 os::physical_memory() >> 10); 2434 st->print("(" UINT64_FORMAT "k free)", 2435 os::available_memory() >> 10); 2436#ifndef _ALLBSD_SOURCE 2437 st->print(", swap " UINT64_FORMAT "k", 2438 ((jlong)si.totalswap * si.mem_unit) >> 10); 2439 st->print("(" UINT64_FORMAT "k free)", 2440 ((jlong)si.freeswap * si.mem_unit) >> 10); 2441#endif 2442 st->cr(); 2443 2444 // meminfo 2445 st->print("\n/proc/meminfo:\n"); 2446 _print_ascii_file("/proc/meminfo", st); 2447 st->cr(); 2448} 2449 2450// Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific 2451// but they're the same for all the bsd arch that we support 2452// and they're the same for solaris but there's no common place to put this. 2453const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR", 2454 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG", 2455 "ILL_COPROC", "ILL_BADSTK" }; 2456 2457const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV", 2458 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES", 2459 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" }; 2460 2461const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" }; 2462 2463const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" }; 2464 2465void os::print_siginfo(outputStream* st, void* siginfo) { 2466 st->print("siginfo:"); 2467 2468 const int buflen = 100; 2469 char buf[buflen]; 2470 siginfo_t *si = (siginfo_t*)siginfo; 2471 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen)); 2472 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) { 2473 st->print("si_errno=%s", buf); 2474 } else { 2475 st->print("si_errno=%d", si->si_errno); 2476 } 2477 const int c = si->si_code; 2478 assert(c > 0, "unexpected si_code"); 2479 switch (si->si_signo) { 2480 case SIGILL: 2481 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]); 2482 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2483 break; 2484 case SIGFPE: 2485 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]); 2486 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2487 break; 2488 case SIGSEGV: 2489 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]); 2490 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2491 break; 2492 case SIGBUS: 2493 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]); 2494 st->print(", si_addr=" PTR_FORMAT, si->si_addr); 2495 break; 2496 default: 2497 st->print(", si_code=%d", si->si_code); 2498 // no si_addr 2499 } 2500 2501 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && 2502 UseSharedSpaces) { 2503 FileMapInfo* mapinfo = FileMapInfo::current_info(); 2504 if (mapinfo->is_in_shared_space(si->si_addr)) { 2505 st->print("\n\nError accessing class data sharing archive." \ 2506 " Mapped file inaccessible during execution, " \ 2507 " possible disk/network problem."); 2508 } 2509 } 2510 st->cr(); 2511} 2512 2513 2514static void print_signal_handler(outputStream* st, int sig, 2515 char* buf, size_t buflen); 2516 2517void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { 2518 st->print_cr("Signal Handlers:"); 2519 print_signal_handler(st, SIGSEGV, buf, buflen); 2520 print_signal_handler(st, SIGBUS , buf, buflen); 2521 print_signal_handler(st, SIGFPE , buf, buflen); 2522 print_signal_handler(st, SIGPIPE, buf, buflen); 2523 print_signal_handler(st, SIGXFSZ, buf, buflen); 2524 print_signal_handler(st, SIGILL , buf, buflen); 2525 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); 2526 print_signal_handler(st, SR_signum, buf, buflen); 2527 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); 2528 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); 2529 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); 2530 print_signal_handler(st, BREAK_SIGNAL, buf, buflen); 2531} 2532 2533static char saved_jvm_path[MAXPATHLEN] = {0}; 2534 2535// Find the full path to the current module, libjvm or libjvm_g 2536void os::jvm_path(char *buf, jint buflen) { 2537 // Error checking. 2538 if (buflen < MAXPATHLEN) { 2539 assert(false, "must use a large-enough buffer"); 2540 buf[0] = '\0'; 2541 return; 2542 } 2543 // Lazy resolve the path to current module. 2544 if (saved_jvm_path[0] != 0) { 2545 strcpy(buf, saved_jvm_path); 2546 return; 2547 } 2548 2549 char dli_fname[MAXPATHLEN]; 2550 bool ret = dll_address_to_library_name( 2551 CAST_FROM_FN_PTR(address, os::jvm_path), 2552 dli_fname, sizeof(dli_fname), NULL); 2553 assert(ret != 0, "cannot locate libjvm"); 2554 char *rp = realpath(dli_fname, buf); 2555 if (rp == NULL) 2556 return; 2557 2558 if (Arguments::created_by_gamma_launcher()) { 2559 // Support for the gamma launcher. Typical value for buf is 2560 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at 2561 // the right place in the string, then assume we are installed in a JDK and 2562 // we're done. Otherwise, check for a JAVA_HOME environment variable and 2563 // construct a path to the JVM being overridden. 2564 2565 const char *p = buf + strlen(buf) - 1; 2566 for (int count = 0; p > buf && count < 5; ++count) { 2567 for (--p; p > buf && *p != '/'; --p) 2568 /* empty */ ; 2569 } 2570 2571 if (strncmp(p, "/jre/lib/", 9) != 0) { 2572 // Look for JAVA_HOME in the environment. 2573 char* java_home_var = ::getenv("JAVA_HOME"); 2574 if (java_home_var != NULL && java_home_var[0] != 0) { 2575 char* jrelib_p; 2576 int len; 2577 2578 // Check the current module name "libjvm" or "libjvm_g". 2579 p = strrchr(buf, '/'); 2580 assert(strstr(p, "/libjvm") == p, "invalid library name"); 2581 p = strstr(p, "_g") ? "_g" : ""; 2582 2583 rp = realpath(java_home_var, buf); 2584 if (rp == NULL) 2585 return; 2586 2587 // determine if this is a legacy image or modules image 2588 // modules image doesn't have "jre" subdirectory 2589 len = strlen(buf); 2590 jrelib_p = buf + len; 2591 2592 // Add the appropriate library subdir 2593 snprintf(jrelib_p, buflen-len, "/jre/lib"); 2594 if (0 != access(buf, F_OK)) { 2595 snprintf(jrelib_p, buflen-len, "/lib"); 2596 } 2597 2598 // Add the appropriate client or server subdir 2599 len = strlen(buf); 2600 jrelib_p = buf + len; 2601 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); 2602 if (0 != access(buf, F_OK)) { 2603 snprintf(jrelib_p, buflen-len, ""); 2604 } 2605 2606 // If the path exists within JAVA_HOME, add the JVM library name 2607 // to complete the path to JVM being overridden. Otherwise fallback 2608 // to the path to the current library. 2609 if (0 == access(buf, F_OK)) { 2610 // Use current module name "libjvm[_g]" instead of 2611 // "libjvm"debug_only("_g")"" since for fastdebug version 2612 // we should have "libjvm" but debug_only("_g") adds "_g"! 2613 len = strlen(buf); 2614 snprintf(buf + len, buflen-len, "/libjvm%s%s", p, JNI_LIB_SUFFIX); 2615 } else { 2616 // Fall back to path of current library 2617 rp = realpath(dli_fname, buf); 2618 if (rp == NULL) 2619 return; 2620 } 2621 } 2622 } 2623 } 2624 2625 strcpy(saved_jvm_path, buf); 2626} 2627 2628void os::print_jni_name_prefix_on(outputStream* st, int args_size) { 2629 // no prefix required, not even "_" 2630} 2631 2632void os::print_jni_name_suffix_on(outputStream* st, int args_size) { 2633 // no suffix required 2634} 2635 2636//////////////////////////////////////////////////////////////////////////////// 2637// sun.misc.Signal support 2638 2639static volatile jint sigint_count = 0; 2640 2641static void 2642UserHandler(int sig, void *siginfo, void *context) { 2643 // 4511530 - sem_post is serialized and handled by the manager thread. When 2644 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We 2645 // don't want to flood the manager thread with sem_post requests. 2646 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) 2647 return; 2648 2649 // Ctrl-C is pressed during error reporting, likely because the error 2650 // handler fails to abort. Let VM die immediately. 2651 if (sig == SIGINT && is_error_reported()) { 2652 os::die(); 2653 } 2654 2655 os::signal_notify(sig); 2656} 2657 2658void* os::user_handler() { 2659 return CAST_FROM_FN_PTR(void*, UserHandler); 2660} 2661 2662extern "C" { 2663 typedef void (*sa_handler_t)(int); 2664 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); 2665} 2666 2667void* os::signal(int signal_number, void* handler) { 2668 struct sigaction sigAct, oldSigAct; 2669 2670 sigfillset(&(sigAct.sa_mask)); 2671 sigAct.sa_flags = SA_RESTART|SA_SIGINFO; 2672 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); 2673 2674 if (sigaction(signal_number, &sigAct, &oldSigAct)) { 2675 // -1 means registration failed 2676 return (void *)-1; 2677 } 2678 2679 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); 2680} 2681 2682void os::signal_raise(int signal_number) { 2683 ::raise(signal_number); 2684} 2685 2686/* 2687 * The following code is moved from os.cpp for making this 2688 * code platform specific, which it is by its very nature. 2689 */ 2690 2691// Will be modified when max signal is changed to be dynamic 2692int os::sigexitnum_pd() { 2693 return NSIG; 2694} 2695 2696// a counter for each possible signal value 2697static volatile jint pending_signals[NSIG+1] = { 0 }; 2698 2699// Bsd(POSIX) specific hand shaking semaphore. 2700#ifdef __APPLE__ 2701static semaphore_t sig_sem; 2702#define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) 2703#define SEM_WAIT(sem) semaphore_wait(sem); 2704#define SEM_POST(sem) semaphore_signal(sem); 2705#else 2706static sem_t sig_sem; 2707#define SEM_INIT(sem, value) sem_init(&sem, 0, value) 2708#define SEM_WAIT(sem) sem_wait(&sem); 2709#define SEM_POST(sem) sem_post(&sem); 2710#endif 2711 2712void os::signal_init_pd() { 2713 // Initialize signal structures 2714 ::memset((void*)pending_signals, 0, sizeof(pending_signals)); 2715 2716 // Initialize signal semaphore 2717 ::SEM_INIT(sig_sem, 0); 2718} 2719 2720void os::signal_notify(int sig) { 2721 Atomic::inc(&pending_signals[sig]); 2722 ::SEM_POST(sig_sem); 2723} 2724 2725static int check_pending_signals(bool wait) { 2726 Atomic::store(0, &sigint_count); 2727 for (;;) { 2728 for (int i = 0; i < NSIG + 1; i++) { 2729 jint n = pending_signals[i]; 2730 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { 2731 return i; 2732 } 2733 } 2734 if (!wait) { 2735 return -1; 2736 } 2737 JavaThread *thread = JavaThread::current(); 2738 ThreadBlockInVM tbivm(thread); 2739 2740 bool threadIsSuspended; 2741 do { 2742 thread->set_suspend_equivalent(); 2743 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 2744 ::SEM_WAIT(sig_sem); 2745 2746 // were we externally suspended while we were waiting? 2747 threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); 2748 if (threadIsSuspended) { 2749 // 2750 // The semaphore has been incremented, but while we were waiting 2751 // another thread suspended us. We don't want to continue running 2752 // while suspended because that would surprise the thread that 2753 // suspended us. 2754 // 2755 ::SEM_POST(sig_sem); 2756 2757 thread->java_suspend_self(); 2758 } 2759 } while (threadIsSuspended); 2760 } 2761} 2762 2763int os::signal_lookup() { 2764 return check_pending_signals(false); 2765} 2766 2767int os::signal_wait() { 2768 return check_pending_signals(true); 2769} 2770 2771//////////////////////////////////////////////////////////////////////////////// 2772// Virtual Memory 2773 2774int os::vm_page_size() { 2775 // Seems redundant as all get out 2776 assert(os::Bsd::page_size() != -1, "must call os::init"); 2777 return os::Bsd::page_size(); 2778} 2779 2780// Solaris allocates memory by pages. 2781int os::vm_allocation_granularity() { 2782 assert(os::Bsd::page_size() != -1, "must call os::init"); 2783 return os::Bsd::page_size(); 2784} 2785 2786// Rationale behind this function: 2787// current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable 2788// mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get 2789// samples for JITted code. Here we create private executable mapping over the code cache 2790// and then we can use standard (well, almost, as mapping can change) way to provide 2791// info for the reporting script by storing timestamp and location of symbol 2792void bsd_wrap_code(char* base, size_t size) { 2793 static volatile jint cnt = 0; 2794 2795 if (!UseOprofile) { 2796 return; 2797 } 2798 2799 char buf[PATH_MAX + 1]; 2800 int num = Atomic::add(1, &cnt); 2801 2802 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", 2803 os::get_temp_directory(), os::current_process_id(), num); 2804 unlink(buf); 2805 2806 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); 2807 2808 if (fd != -1) { 2809 off_t rv = ::lseek(fd, size-2, SEEK_SET); 2810 if (rv != (off_t)-1) { 2811 if (::write(fd, "", 1) == 1) { 2812 mmap(base, size, 2813 PROT_READ|PROT_WRITE|PROT_EXEC, 2814 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); 2815 } 2816 } 2817 ::close(fd); 2818 unlink(buf); 2819 } 2820} 2821 2822// NOTE: Bsd kernel does not really reserve the pages for us. 2823// All it does is to check if there are enough free pages 2824// left at the time of mmap(). This could be a potential 2825// problem. 2826bool os::commit_memory(char* addr, size_t size, bool exec) { 2827 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2828#ifdef __OpenBSD__ 2829 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 2830 return ::mprotect(addr, size, prot) == 0; 2831#else 2832 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, 2833 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); 2834 return res != (uintptr_t) MAP_FAILED; 2835#endif 2836} 2837 2838#ifndef _ALLBSD_SOURCE 2839// Define MAP_HUGETLB here so we can build HotSpot on old systems. 2840#ifndef MAP_HUGETLB 2841#define MAP_HUGETLB 0x40000 2842#endif 2843 2844// Define MADV_HUGEPAGE here so we can build HotSpot on old systems. 2845#ifndef MADV_HUGEPAGE 2846#define MADV_HUGEPAGE 14 2847#endif 2848#endif 2849 2850bool os::commit_memory(char* addr, size_t size, size_t alignment_hint, 2851 bool exec) { 2852#ifndef _ALLBSD_SOURCE 2853 if (UseHugeTLBFS && alignment_hint > (size_t)vm_page_size()) { 2854 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; 2855 uintptr_t res = 2856 (uintptr_t) ::mmap(addr, size, prot, 2857 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS|MAP_HUGETLB, 2858 -1, 0); 2859 return res != (uintptr_t) MAP_FAILED; 2860 } 2861#endif 2862 2863 return commit_memory(addr, size, exec); 2864} 2865 2866void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { 2867#ifndef _ALLBSD_SOURCE 2868 if (UseHugeTLBFS && alignment_hint > (size_t)vm_page_size()) { 2869 // We don't check the return value: madvise(MADV_HUGEPAGE) may not 2870 // be supported or the memory may already be backed by huge pages. 2871 ::madvise(addr, bytes, MADV_HUGEPAGE); 2872 } 2873#endif 2874} 2875 2876void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) { 2877 ::madvise(addr, bytes, MADV_DONTNEED); 2878} 2879 2880void os::numa_make_global(char *addr, size_t bytes) { 2881} 2882 2883void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { 2884} 2885 2886bool os::numa_topology_changed() { return false; } 2887 2888size_t os::numa_get_groups_num() { 2889 return 1; 2890} 2891 2892int os::numa_get_group_id() { 2893 return 0; 2894} 2895 2896size_t os::numa_get_leaf_groups(int *ids, size_t size) { 2897 if (size > 0) { 2898 ids[0] = 0; 2899 return 1; 2900 } 2901 return 0; 2902} 2903 2904bool os::get_page_info(char *start, page_info* info) { 2905 return false; 2906} 2907 2908char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { 2909 return end; 2910} 2911 2912#ifndef _ALLBSD_SOURCE 2913// Something to do with the numa-aware allocator needs these symbols 2914extern "C" JNIEXPORT void numa_warn(int number, char *where, ...) { } 2915extern "C" JNIEXPORT void numa_error(char *where) { } 2916extern "C" JNIEXPORT int fork1() { return fork(); } 2917 2918 2919// If we are running with libnuma version > 2, then we should 2920// be trying to use symbols with versions 1.1 2921// If we are running with earlier version, which did not have symbol versions, 2922// we should use the base version. 2923void* os::Bsd::libnuma_dlsym(void* handle, const char *name) { 2924 void *f = dlvsym(handle, name, "libnuma_1.1"); 2925 if (f == NULL) { 2926 f = dlsym(handle, name); 2927 } 2928 return f; 2929} 2930 2931bool os::Bsd::libnuma_init() { 2932 // sched_getcpu() should be in libc. 2933 set_sched_getcpu(CAST_TO_FN_PTR(sched_getcpu_func_t, 2934 dlsym(RTLD_DEFAULT, "sched_getcpu"))); 2935 2936 if (sched_getcpu() != -1) { // Does it work? 2937 void *handle = dlopen("libnuma.so.1", RTLD_LAZY); 2938 if (handle != NULL) { 2939 set_numa_node_to_cpus(CAST_TO_FN_PTR(numa_node_to_cpus_func_t, 2940 libnuma_dlsym(handle, "numa_node_to_cpus"))); 2941 set_numa_max_node(CAST_TO_FN_PTR(numa_max_node_func_t, 2942 libnuma_dlsym(handle, "numa_max_node"))); 2943 set_numa_available(CAST_TO_FN_PTR(numa_available_func_t, 2944 libnuma_dlsym(handle, "numa_available"))); 2945 set_numa_tonode_memory(CAST_TO_FN_PTR(numa_tonode_memory_func_t, 2946 libnuma_dlsym(handle, "numa_tonode_memory"))); 2947 set_numa_interleave_memory(CAST_TO_FN_PTR(numa_interleave_memory_func_t, 2948 libnuma_dlsym(handle, "numa_interleave_memory"))); 2949 2950 2951 if (numa_available() != -1) { 2952 set_numa_all_nodes((unsigned long*)libnuma_dlsym(handle, "numa_all_nodes")); 2953 // Create a cpu -> node mapping 2954 _cpu_to_node = new (ResourceObj::C_HEAP) GrowableArray<int>(0, true); 2955 rebuild_cpu_to_node_map(); 2956 return true; 2957 } 2958 } 2959 } 2960 return false; 2961} 2962 2963// rebuild_cpu_to_node_map() constructs a table mapping cpud id to node id. 2964// The table is later used in get_node_by_cpu(). 2965void os::Bsd::rebuild_cpu_to_node_map() { 2966 const size_t NCPUS = 32768; // Since the buffer size computation is very obscure 2967 // in libnuma (possible values are starting from 16, 2968 // and continuing up with every other power of 2, but less 2969 // than the maximum number of CPUs supported by kernel), and 2970 // is a subject to change (in libnuma version 2 the requirements 2971 // are more reasonable) we'll just hardcode the number they use 2972 // in the library. 2973 const size_t BitsPerCLong = sizeof(long) * CHAR_BIT; 2974 2975 size_t cpu_num = os::active_processor_count(); 2976 size_t cpu_map_size = NCPUS / BitsPerCLong; 2977 size_t cpu_map_valid_size = 2978 MIN2((cpu_num + BitsPerCLong - 1) / BitsPerCLong, cpu_map_size); 2979 2980 cpu_to_node()->clear(); 2981 cpu_to_node()->at_grow(cpu_num - 1); 2982 size_t node_num = numa_get_groups_num(); 2983 2984 unsigned long *cpu_map = NEW_C_HEAP_ARRAY(unsigned long, cpu_map_size); 2985 for (size_t i = 0; i < node_num; i++) { 2986 if (numa_node_to_cpus(i, cpu_map, cpu_map_size * sizeof(unsigned long)) != -1) { 2987 for (size_t j = 0; j < cpu_map_valid_size; j++) { 2988 if (cpu_map[j] != 0) { 2989 for (size_t k = 0; k < BitsPerCLong; k++) { 2990 if (cpu_map[j] & (1UL << k)) { 2991 cpu_to_node()->at_put(j * BitsPerCLong + k, i); 2992 } 2993 } 2994 } 2995 } 2996 } 2997 } 2998 FREE_C_HEAP_ARRAY(unsigned long, cpu_map); 2999} 3000 3001int os::Bsd::get_node_by_cpu(int cpu_id) { 3002 if (cpu_to_node() != NULL && cpu_id >= 0 && cpu_id < cpu_to_node()->length()) { 3003 return cpu_to_node()->at(cpu_id); 3004 } 3005 return -1; 3006} 3007 3008GrowableArray<int>* os::Bsd::_cpu_to_node; 3009os::Bsd::sched_getcpu_func_t os::Bsd::_sched_getcpu; 3010os::Bsd::numa_node_to_cpus_func_t os::Bsd::_numa_node_to_cpus; 3011os::Bsd::numa_max_node_func_t os::Bsd::_numa_max_node; 3012os::Bsd::numa_available_func_t os::Bsd::_numa_available; 3013os::Bsd::numa_tonode_memory_func_t os::Bsd::_numa_tonode_memory; 3014os::Bsd::numa_interleave_memory_func_t os::Bsd::_numa_interleave_memory; 3015unsigned long* os::Bsd::_numa_all_nodes; 3016#endif 3017 3018bool os::uncommit_memory(char* addr, size_t size) { 3019#ifdef __OpenBSD__ 3020 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD 3021 return ::mprotect(addr, size, PROT_NONE) == 0; 3022#else 3023 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, 3024 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); 3025 return res != (uintptr_t) MAP_FAILED; 3026#endif 3027} 3028 3029bool os::create_stack_guard_pages(char* addr, size_t size) { 3030 return os::commit_memory(addr, size); 3031} 3032 3033// If this is a growable mapping, remove the guard pages entirely by 3034// munmap()ping them. If not, just call uncommit_memory(). 3035bool os::remove_stack_guard_pages(char* addr, size_t size) { 3036 return os::uncommit_memory(addr, size); 3037} 3038 3039static address _highest_vm_reserved_address = NULL; 3040 3041// If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory 3042// at 'requested_addr'. If there are existing memory mappings at the same 3043// location, however, they will be overwritten. If 'fixed' is false, 3044// 'requested_addr' is only treated as a hint, the return value may or 3045// may not start from the requested address. Unlike Bsd mmap(), this 3046// function returns NULL to indicate failure. 3047static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { 3048 char * addr; 3049 int flags; 3050 3051 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; 3052 if (fixed) { 3053 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); 3054 flags |= MAP_FIXED; 3055 } 3056 3057 // Map uncommitted pages PROT_READ and PROT_WRITE, change access 3058 // to PROT_EXEC if executable when we commit the page. 3059 addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE, 3060 flags, -1, 0); 3061 3062 if (addr != MAP_FAILED) { 3063 // anon_mmap() should only get called during VM initialization, 3064 // don't need lock (actually we can skip locking even it can be called 3065 // from multiple threads, because _highest_vm_reserved_address is just a 3066 // hint about the upper limit of non-stack memory regions.) 3067 if ((address)addr + bytes > _highest_vm_reserved_address) { 3068 _highest_vm_reserved_address = (address)addr + bytes; 3069 } 3070 } 3071 3072 return addr == MAP_FAILED ? NULL : addr; 3073} 3074 3075// Don't update _highest_vm_reserved_address, because there might be memory 3076// regions above addr + size. If so, releasing a memory region only creates 3077// a hole in the address space, it doesn't help prevent heap-stack collision. 3078// 3079static int anon_munmap(char * addr, size_t size) { 3080 return ::munmap(addr, size) == 0; 3081} 3082 3083char* os::reserve_memory(size_t bytes, char* requested_addr, 3084 size_t alignment_hint) { 3085 return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); 3086} 3087 3088bool os::release_memory(char* addr, size_t size) { 3089 return anon_munmap(addr, size); 3090} 3091 3092static address highest_vm_reserved_address() { 3093 return _highest_vm_reserved_address; 3094} 3095 3096static bool bsd_mprotect(char* addr, size_t size, int prot) { 3097 // Bsd wants the mprotect address argument to be page aligned. 3098 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); 3099 3100 // According to SUSv3, mprotect() should only be used with mappings 3101 // established by mmap(), and mmap() always maps whole pages. Unaligned 3102 // 'addr' likely indicates problem in the VM (e.g. trying to change 3103 // protection of malloc'ed or statically allocated memory). Check the 3104 // caller if you hit this assert. 3105 assert(addr == bottom, "sanity check"); 3106 3107 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); 3108 return ::mprotect(bottom, size, prot) == 0; 3109} 3110 3111// Set protections specified 3112bool os::protect_memory(char* addr, size_t bytes, ProtType prot, 3113 bool is_committed) { 3114 unsigned int p = 0; 3115 switch (prot) { 3116 case MEM_PROT_NONE: p = PROT_NONE; break; 3117 case MEM_PROT_READ: p = PROT_READ; break; 3118 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; 3119 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; 3120 default: 3121 ShouldNotReachHere(); 3122 } 3123 // is_committed is unused. 3124 return bsd_mprotect(addr, bytes, p); 3125} 3126 3127bool os::guard_memory(char* addr, size_t size) { 3128 return bsd_mprotect(addr, size, PROT_NONE); 3129} 3130 3131bool os::unguard_memory(char* addr, size_t size) { 3132 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); 3133} 3134 3135bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { 3136 bool result = false; 3137#ifndef _ALLBSD_SOURCE 3138 void *p = mmap (NULL, page_size, PROT_READ|PROT_WRITE, 3139 MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB, 3140 -1, 0); 3141 3142 if (p != (void *) -1) { 3143 // We don't know if this really is a huge page or not. 3144 FILE *fp = fopen("/proc/self/maps", "r"); 3145 if (fp) { 3146 while (!feof(fp)) { 3147 char chars[257]; 3148 long x = 0; 3149 if (fgets(chars, sizeof(chars), fp)) { 3150 if (sscanf(chars, "%lx-%*x", &x) == 1 3151 && x == (long)p) { 3152 if (strstr (chars, "hugepage")) { 3153 result = true; 3154 break; 3155 } 3156 } 3157 } 3158 } 3159 fclose(fp); 3160 } 3161 munmap (p, page_size); 3162 if (result) 3163 return true; 3164 } 3165 3166 if (warn) { 3167 warning("HugeTLBFS is not supported by the operating system."); 3168 } 3169#endif 3170 3171 return result; 3172} 3173 3174/* 3175* Set the coredump_filter bits to include largepages in core dump (bit 6) 3176* 3177* From the coredump_filter documentation: 3178* 3179* - (bit 0) anonymous private memory 3180* - (bit 1) anonymous shared memory 3181* - (bit 2) file-backed private memory 3182* - (bit 3) file-backed shared memory 3183* - (bit 4) ELF header pages in file-backed private memory areas (it is 3184* effective only if the bit 2 is cleared) 3185* - (bit 5) hugetlb private memory 3186* - (bit 6) hugetlb shared memory 3187*/ 3188static void set_coredump_filter(void) { 3189 FILE *f; 3190 long cdm; 3191 3192 if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) { 3193 return; 3194 } 3195 3196 if (fscanf(f, "%lx", &cdm) != 1) { 3197 fclose(f); 3198 return; 3199 } 3200 3201 rewind(f); 3202 3203 if ((cdm & LARGEPAGES_BIT) == 0) { 3204 cdm |= LARGEPAGES_BIT; 3205 fprintf(f, "%#lx", cdm); 3206 } 3207 3208 fclose(f); 3209} 3210 3211// Large page support 3212 3213static size_t _large_page_size = 0; 3214 3215void os::large_page_init() { 3216#ifndef _ALLBSD_SOURCE 3217 if (!UseLargePages) { 3218 UseHugeTLBFS = false; 3219 UseSHM = false; 3220 return; 3221 } 3222 3223 if (FLAG_IS_DEFAULT(UseHugeTLBFS) && FLAG_IS_DEFAULT(UseSHM)) { 3224 // If UseLargePages is specified on the command line try both methods, 3225 // if it's default, then try only HugeTLBFS. 3226 if (FLAG_IS_DEFAULT(UseLargePages)) { 3227 UseHugeTLBFS = true; 3228 } else { 3229 UseHugeTLBFS = UseSHM = true; 3230 } 3231 } 3232 3233 if (LargePageSizeInBytes) { 3234 _large_page_size = LargePageSizeInBytes; 3235 } else { 3236 // large_page_size on Bsd is used to round up heap size. x86 uses either 3237 // 2M or 4M page, depending on whether PAE (Physical Address Extensions) 3238 // mode is enabled. AMD64/EM64T uses 2M page in 64bit mode. IA64 can use 3239 // page as large as 256M. 3240 // 3241 // Here we try to figure out page size by parsing /proc/meminfo and looking 3242 // for a line with the following format: 3243 // Hugepagesize: 2048 kB 3244 // 3245 // If we can't determine the value (e.g. /proc is not mounted, or the text 3246 // format has been changed), we'll use the largest page size supported by 3247 // the processor. 3248 3249#ifndef ZERO 3250 _large_page_size = IA32_ONLY(4 * M) AMD64_ONLY(2 * M) IA64_ONLY(256 * M) SPARC_ONLY(4 * M) 3251 ARM_ONLY(2 * M) PPC_ONLY(4 * M); 3252#endif // ZERO 3253 3254 FILE *fp = fopen("/proc/meminfo", "r"); 3255 if (fp) { 3256 while (!feof(fp)) { 3257 int x = 0; 3258 char buf[16]; 3259 if (fscanf(fp, "Hugepagesize: %d", &x) == 1) { 3260 if (x && fgets(buf, sizeof(buf), fp) && strcmp(buf, " kB\n") == 0) { 3261 _large_page_size = x * K; 3262 break; 3263 } 3264 } else { 3265 // skip to next line 3266 for (;;) { 3267 int ch = fgetc(fp); 3268 if (ch == EOF || ch == (int)'\n') break; 3269 } 3270 } 3271 } 3272 fclose(fp); 3273 } 3274 } 3275 3276 // print a warning if any large page related flag is specified on command line 3277 bool warn_on_failure = !FLAG_IS_DEFAULT(UseHugeTLBFS); 3278 3279 const size_t default_page_size = (size_t)Bsd::page_size(); 3280 if (_large_page_size > default_page_size) { 3281 _page_sizes[0] = _large_page_size; 3282 _page_sizes[1] = default_page_size; 3283 _page_sizes[2] = 0; 3284 } 3285 UseHugeTLBFS = UseHugeTLBFS && 3286 Bsd::hugetlbfs_sanity_check(warn_on_failure, _large_page_size); 3287 3288 if (UseHugeTLBFS) 3289 UseSHM = false; 3290 3291 UseLargePages = UseHugeTLBFS || UseSHM; 3292 3293 set_coredump_filter(); 3294#endif 3295} 3296 3297#ifndef _ALLBSD_SOURCE 3298#ifndef SHM_HUGETLB 3299#define SHM_HUGETLB 04000 3300#endif 3301#endif 3302 3303char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) { 3304 // "exec" is passed in but not used. Creating the shared image for 3305 // the code cache doesn't have an SHM_X executable permission to check. 3306 assert(UseLargePages && UseSHM, "only for SHM large pages"); 3307 3308 key_t key = IPC_PRIVATE; 3309 char *addr; 3310 3311 bool warn_on_failure = UseLargePages && 3312 (!FLAG_IS_DEFAULT(UseLargePages) || 3313 !FLAG_IS_DEFAULT(LargePageSizeInBytes) 3314 ); 3315 char msg[128]; 3316 3317 // Create a large shared memory region to attach to based on size. 3318 // Currently, size is the total size of the heap 3319#ifndef _ALLBSD_SOURCE 3320 int shmid = shmget(key, bytes, SHM_HUGETLB|IPC_CREAT|SHM_R|SHM_W); 3321#else 3322 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); 3323#endif 3324 if (shmid == -1) { 3325 // Possible reasons for shmget failure: 3326 // 1. shmmax is too small for Java heap. 3327 // > check shmmax value: cat /proc/sys/kernel/shmmax 3328 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax 3329 // 2. not enough large page memory. 3330 // > check available large pages: cat /proc/meminfo 3331 // > increase amount of large pages: 3332 // echo new_value > /proc/sys/vm/nr_hugepages 3333 // Note 1: different Bsd may use different name for this property, 3334 // e.g. on Redhat AS-3 it is "hugetlb_pool". 3335 // Note 2: it's possible there's enough physical memory available but 3336 // they are so fragmented after a long run that they can't 3337 // coalesce into large pages. Try to reserve large pages when 3338 // the system is still "fresh". 3339 if (warn_on_failure) { 3340 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno); 3341 warning(msg); 3342 } 3343 return NULL; 3344 } 3345 3346 // attach to the region 3347 addr = (char*)shmat(shmid, req_addr, 0); 3348 int err = errno; 3349 3350 // Remove shmid. If shmat() is successful, the actual shared memory segment 3351 // will be deleted when it's detached by shmdt() or when the process 3352 // terminates. If shmat() is not successful this will remove the shared 3353 // segment immediately. 3354 shmctl(shmid, IPC_RMID, NULL); 3355 3356 if ((intptr_t)addr == -1) { 3357 if (warn_on_failure) { 3358 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err); 3359 warning(msg); 3360 } 3361 return NULL; 3362 } 3363 3364 return addr; 3365} 3366 3367bool os::release_memory_special(char* base, size_t bytes) { 3368 // detaching the SHM segment will also delete it, see reserve_memory_special() 3369 int rslt = shmdt(base); 3370 return rslt == 0; 3371} 3372 3373size_t os::large_page_size() { 3374 return _large_page_size; 3375} 3376 3377// HugeTLBFS allows application to commit large page memory on demand; 3378// with SysV SHM the entire memory region must be allocated as shared 3379// memory. 3380bool os::can_commit_large_page_memory() { 3381 return UseHugeTLBFS; 3382} 3383 3384bool os::can_execute_large_page_memory() { 3385 return UseHugeTLBFS; 3386} 3387 3388// Reserve memory at an arbitrary address, only if that area is 3389// available (and not reserved for something else). 3390 3391char* os::attempt_reserve_memory_at(size_t bytes, char* requested_addr) { 3392 const int max_tries = 10; 3393 char* base[max_tries]; 3394 size_t size[max_tries]; 3395 const size_t gap = 0x000000; 3396 3397 // Assert only that the size is a multiple of the page size, since 3398 // that's all that mmap requires, and since that's all we really know 3399 // about at this low abstraction level. If we need higher alignment, 3400 // we can either pass an alignment to this method or verify alignment 3401 // in one of the methods further up the call chain. See bug 5044738. 3402 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); 3403 3404 // Repeatedly allocate blocks until the block is allocated at the 3405 // right spot. Give up after max_tries. Note that reserve_memory() will 3406 // automatically update _highest_vm_reserved_address if the call is 3407 // successful. The variable tracks the highest memory address every reserved 3408 // by JVM. It is used to detect heap-stack collision if running with 3409 // fixed-stack BsdThreads. Because here we may attempt to reserve more 3410 // space than needed, it could confuse the collision detecting code. To 3411 // solve the problem, save current _highest_vm_reserved_address and 3412 // calculate the correct value before return. 3413 address old_highest = _highest_vm_reserved_address; 3414 3415 // Bsd mmap allows caller to pass an address as hint; give it a try first, 3416 // if kernel honors the hint then we can return immediately. 3417 char * addr = anon_mmap(requested_addr, bytes, false); 3418 if (addr == requested_addr) { 3419 return requested_addr; 3420 } 3421 3422 if (addr != NULL) { 3423 // mmap() is successful but it fails to reserve at the requested address 3424 anon_munmap(addr, bytes); 3425 } 3426 3427 int i; 3428 for (i = 0; i < max_tries; ++i) { 3429 base[i] = reserve_memory(bytes); 3430 3431 if (base[i] != NULL) { 3432 // Is this the block we wanted? 3433 if (base[i] == requested_addr) { 3434 size[i] = bytes; 3435 break; 3436 } 3437 3438 // Does this overlap the block we wanted? Give back the overlapped 3439 // parts and try again. 3440 3441 size_t top_overlap = requested_addr + (bytes + gap) - base[i]; 3442 if (top_overlap >= 0 && top_overlap < bytes) { 3443 unmap_memory(base[i], top_overlap); 3444 base[i] += top_overlap; 3445 size[i] = bytes - top_overlap; 3446 } else { 3447 size_t bottom_overlap = base[i] + bytes - requested_addr; 3448 if (bottom_overlap >= 0 && bottom_overlap < bytes) { 3449 unmap_memory(requested_addr, bottom_overlap); 3450 size[i] = bytes - bottom_overlap; 3451 } else { 3452 size[i] = bytes; 3453 } 3454 } 3455 } 3456 } 3457 3458 // Give back the unused reserved pieces. 3459 3460 for (int j = 0; j < i; ++j) { 3461 if (base[j] != NULL) { 3462 unmap_memory(base[j], size[j]); 3463 } 3464 } 3465 3466 if (i < max_tries) { 3467 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); 3468 return requested_addr; 3469 } else { 3470 _highest_vm_reserved_address = old_highest; 3471 return NULL; 3472 } 3473} 3474 3475size_t os::read(int fd, void *buf, unsigned int nBytes) { 3476 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); 3477} 3478 3479// TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation. 3480// Solaris uses poll(), bsd uses park(). 3481// Poll() is likely a better choice, assuming that Thread.interrupt() 3482// generates a SIGUSRx signal. Note that SIGUSR1 can interfere with 3483// SIGSEGV, see 4355769. 3484 3485int os::sleep(Thread* thread, jlong millis, bool interruptible) { 3486 assert(thread == Thread::current(), "thread consistency check"); 3487 3488 ParkEvent * const slp = thread->_SleepEvent ; 3489 slp->reset() ; 3490 OrderAccess::fence() ; 3491 3492 if (interruptible) { 3493 jlong prevtime = javaTimeNanos(); 3494 3495 for (;;) { 3496 if (os::is_interrupted(thread, true)) { 3497 return OS_INTRPT; 3498 } 3499 3500 jlong newtime = javaTimeNanos(); 3501 3502 if (newtime - prevtime < 0) { 3503 // time moving backwards, should only happen if no monotonic clock 3504 // not a guarantee() because JVM should not abort on kernel/glibc bugs 3505 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 3506 } else { 3507 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 3508 } 3509 3510 if(millis <= 0) { 3511 return OS_OK; 3512 } 3513 3514 prevtime = newtime; 3515 3516 { 3517 assert(thread->is_Java_thread(), "sanity check"); 3518 JavaThread *jt = (JavaThread *) thread; 3519 ThreadBlockInVM tbivm(jt); 3520 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 3521 3522 jt->set_suspend_equivalent(); 3523 // cleared by handle_special_suspend_equivalent_condition() or 3524 // java_suspend_self() via check_and_wait_while_suspended() 3525 3526 slp->park(millis); 3527 3528 // were we externally suspended while we were waiting? 3529 jt->check_and_wait_while_suspended(); 3530 } 3531 } 3532 } else { 3533 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 3534 jlong prevtime = javaTimeNanos(); 3535 3536 for (;;) { 3537 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 3538 // the 1st iteration ... 3539 jlong newtime = javaTimeNanos(); 3540 3541 if (newtime - prevtime < 0) { 3542 // time moving backwards, should only happen if no monotonic clock 3543 // not a guarantee() because JVM should not abort on kernel/glibc bugs 3544 assert(!Bsd::supports_monotonic_clock(), "time moving backwards"); 3545 } else { 3546 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 3547 } 3548 3549 if(millis <= 0) break ; 3550 3551 prevtime = newtime; 3552 slp->park(millis); 3553 } 3554 return OS_OK ; 3555 } 3556} 3557 3558int os::naked_sleep() { 3559 // %% make the sleep time an integer flag. for now use 1 millisec. 3560 return os::sleep(Thread::current(), 1, false); 3561} 3562 3563// Sleep forever; naked call to OS-specific sleep; use with CAUTION 3564void os::infinite_sleep() { 3565 while (true) { // sleep forever ... 3566 ::sleep(100); // ... 100 seconds at a time 3567 } 3568} 3569 3570// Used to convert frequent JVM_Yield() to nops 3571bool os::dont_yield() { 3572 return DontYieldALot; 3573} 3574 3575void os::yield() { 3576 sched_yield(); 3577} 3578 3579os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;} 3580 3581void os::yield_all(int attempts) { 3582 // Yields to all threads, including threads with lower priorities 3583 // Threads on Bsd are all with same priority. The Solaris style 3584 // os::yield_all() with nanosleep(1ms) is not necessary. 3585 sched_yield(); 3586} 3587 3588// Called from the tight loops to possibly influence time-sharing heuristics 3589void os::loop_breaker(int attempts) { 3590 os::yield_all(attempts); 3591} 3592 3593//////////////////////////////////////////////////////////////////////////////// 3594// thread priority support 3595 3596// Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER 3597// only supports dynamic priority, static priority must be zero. For real-time 3598// applications, Bsd supports SCHED_RR which allows static priority (1-99). 3599// However, for large multi-threaded applications, SCHED_RR is not only slower 3600// than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out 3601// of 5 runs - Sep 2005). 3602// 3603// The following code actually changes the niceness of kernel-thread/LWP. It 3604// has an assumption that setpriority() only modifies one kernel-thread/LWP, 3605// not the entire user process, and user level threads are 1:1 mapped to kernel 3606// threads. It has always been the case, but could change in the future. For 3607// this reason, the code should not be used as default (ThreadPriorityPolicy=0). 3608// It is only used when ThreadPriorityPolicy=1 and requires root privilege. 3609 3610#if defined(_ALLBSD_SOURCE) && !defined(__APPLE__) 3611int os::java_to_os_priority[CriticalPriority + 1] = { 3612 19, // 0 Entry should never be used 3613 3614 0, // 1 MinPriority 3615 3, // 2 3616 6, // 3 3617 3618 10, // 4 3619 15, // 5 NormPriority 3620 18, // 6 3621 3622 21, // 7 3623 25, // 8 3624 28, // 9 NearMaxPriority 3625 3626 31, // 10 MaxPriority 3627 3628 31 // 11 CriticalPriority 3629}; 3630#elif defined(__APPLE__) 3631/* Using Mach high-level priority assignments */ 3632int os::java_to_os_priority[CriticalPriority + 1] = { 3633 0, // 0 Entry should never be used (MINPRI_USER) 3634 3635 27, // 1 MinPriority 3636 28, // 2 3637 29, // 3 3638 3639 30, // 4 3640 31, // 5 NormPriority (BASEPRI_DEFAULT) 3641 32, // 6 3642 3643 33, // 7 3644 34, // 8 3645 35, // 9 NearMaxPriority 3646 3647 36, // 10 MaxPriority 3648 3649 36 // 11 CriticalPriority 3650}; 3651#else 3652int os::java_to_os_priority[CriticalPriority + 1] = { 3653 19, // 0 Entry should never be used 3654 3655 4, // 1 MinPriority 3656 3, // 2 3657 2, // 3 3658 3659 1, // 4 3660 0, // 5 NormPriority 3661 -1, // 6 3662 3663 -2, // 7 3664 -3, // 8 3665 -4, // 9 NearMaxPriority 3666 3667 -5, // 10 MaxPriority 3668 3669 -5 // 11 CriticalPriority 3670}; 3671#endif 3672 3673static int prio_init() { 3674 if (ThreadPriorityPolicy == 1) { 3675 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 3676 // if effective uid is not root. Perhaps, a more elegant way of doing 3677 // this is to test CAP_SYS_NICE capability, but that will require libcap.so 3678 if (geteuid() != 0) { 3679 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { 3680 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); 3681 } 3682 ThreadPriorityPolicy = 0; 3683 } 3684 } 3685 if (UseCriticalJavaThreadPriority) { 3686 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; 3687 } 3688 return 0; 3689} 3690 3691OSReturn os::set_native_priority(Thread* thread, int newpri) { 3692 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK; 3693 3694#ifdef __OpenBSD__ 3695 // OpenBSD pthread_setprio starves low priority threads 3696 return OS_OK; 3697#elif defined(__FreeBSD__) 3698 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); 3699#elif defined(__APPLE__) || defined(__NetBSD__) 3700 struct sched_param sp; 3701 int policy; 3702 pthread_t self = pthread_self(); 3703 3704 if (pthread_getschedparam(self, &policy, &sp) != 0) 3705 return OS_ERR; 3706 3707 sp.sched_priority = newpri; 3708 if (pthread_setschedparam(self, policy, &sp) != 0) 3709 return OS_ERR; 3710 3711 return OS_OK; 3712#else 3713 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); 3714 return (ret == 0) ? OS_OK : OS_ERR; 3715#endif 3716} 3717 3718OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { 3719 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) { 3720 *priority_ptr = java_to_os_priority[NormPriority]; 3721 return OS_OK; 3722 } 3723 3724 errno = 0; 3725#if defined(__OpenBSD__) || defined(__FreeBSD__) 3726 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); 3727#elif defined(__APPLE__) || defined(__NetBSD__) 3728 int policy; 3729 struct sched_param sp; 3730 3731 pthread_getschedparam(pthread_self(), &policy, &sp); 3732 *priority_ptr = sp.sched_priority; 3733#else 3734 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); 3735#endif 3736 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); 3737} 3738 3739// Hint to the underlying OS that a task switch would not be good. 3740// Void return because it's a hint and can fail. 3741void os::hint_no_preempt() {} 3742 3743//////////////////////////////////////////////////////////////////////////////// 3744// suspend/resume support 3745 3746// the low-level signal-based suspend/resume support is a remnant from the 3747// old VM-suspension that used to be for java-suspension, safepoints etc, 3748// within hotspot. Now there is a single use-case for this: 3749// - calling get_thread_pc() on the VMThread by the flat-profiler task 3750// that runs in the watcher thread. 3751// The remaining code is greatly simplified from the more general suspension 3752// code that used to be used. 3753// 3754// The protocol is quite simple: 3755// - suspend: 3756// - sends a signal to the target thread 3757// - polls the suspend state of the osthread using a yield loop 3758// - target thread signal handler (SR_handler) sets suspend state 3759// and blocks in sigsuspend until continued 3760// - resume: 3761// - sets target osthread state to continue 3762// - sends signal to end the sigsuspend loop in the SR_handler 3763// 3764// Note that the SR_lock plays no role in this suspend/resume protocol. 3765// 3766 3767static void resume_clear_context(OSThread *osthread) { 3768 osthread->set_ucontext(NULL); 3769 osthread->set_siginfo(NULL); 3770 3771 // notify the suspend action is completed, we have now resumed 3772 osthread->sr.clear_suspended(); 3773} 3774 3775static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { 3776 osthread->set_ucontext(context); 3777 osthread->set_siginfo(siginfo); 3778} 3779 3780// 3781// Handler function invoked when a thread's execution is suspended or 3782// resumed. We have to be careful that only async-safe functions are 3783// called here (Note: most pthread functions are not async safe and 3784// should be avoided.) 3785// 3786// Note: sigwait() is a more natural fit than sigsuspend() from an 3787// interface point of view, but sigwait() prevents the signal hander 3788// from being run. libpthread would get very confused by not having 3789// its signal handlers run and prevents sigwait()'s use with the 3790// mutex granting granting signal. 3791// 3792// Currently only ever called on the VMThread 3793// 3794static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { 3795 // Save and restore errno to avoid confusing native code with EINTR 3796 // after sigsuspend. 3797 int old_errno = errno; 3798 3799 Thread* thread = Thread::current(); 3800 OSThread* osthread = thread->osthread(); 3801 assert(thread->is_VM_thread(), "Must be VMThread"); 3802 // read current suspend action 3803 int action = osthread->sr.suspend_action(); 3804 if (action == SR_SUSPEND) { 3805 suspend_save_context(osthread, siginfo, context); 3806 3807 // Notify the suspend action is about to be completed. do_suspend() 3808 // waits until SR_SUSPENDED is set and then returns. We will wait 3809 // here for a resume signal and that completes the suspend-other 3810 // action. do_suspend/do_resume is always called as a pair from 3811 // the same thread - so there are no races 3812 3813 // notify the caller 3814 osthread->sr.set_suspended(); 3815 3816 sigset_t suspend_set; // signals for sigsuspend() 3817 3818 // get current set of blocked signals and unblock resume signal 3819 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); 3820 sigdelset(&suspend_set, SR_signum); 3821 3822 // wait here until we are resumed 3823 do { 3824 sigsuspend(&suspend_set); 3825 // ignore all returns until we get a resume signal 3826 } while (osthread->sr.suspend_action() != SR_CONTINUE); 3827 3828 resume_clear_context(osthread); 3829 3830 } else { 3831 assert(action == SR_CONTINUE, "unexpected sr action"); 3832 // nothing special to do - just leave the handler 3833 } 3834 3835 errno = old_errno; 3836} 3837 3838 3839static int SR_initialize() { 3840 struct sigaction act; 3841 char *s; 3842 /* Get signal number to use for suspend/resume */ 3843 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { 3844 int sig = ::strtol(s, 0, 10); 3845 if (sig > 0 || sig < NSIG) { 3846 SR_signum = sig; 3847 } 3848 } 3849 3850 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, 3851 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); 3852 3853 sigemptyset(&SR_sigset); 3854 sigaddset(&SR_sigset, SR_signum); 3855 3856 /* Set up signal handler for suspend/resume */ 3857 act.sa_flags = SA_RESTART|SA_SIGINFO; 3858 act.sa_handler = (void (*)(int)) SR_handler; 3859 3860 // SR_signum is blocked by default. 3861 // 4528190 - We also need to block pthread restart signal (32 on all 3862 // supported Bsd platforms). Note that BsdThreads need to block 3863 // this signal for all threads to work properly. So we don't have 3864 // to use hard-coded signal number when setting up the mask. 3865 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); 3866 3867 if (sigaction(SR_signum, &act, 0) == -1) { 3868 return -1; 3869 } 3870 3871 // Save signal flag 3872 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); 3873 return 0; 3874} 3875 3876static int SR_finalize() { 3877 return 0; 3878} 3879 3880 3881// returns true on success and false on error - really an error is fatal 3882// but this seems the normal response to library errors 3883static bool do_suspend(OSThread* osthread) { 3884 // mark as suspended and send signal 3885 osthread->sr.set_suspend_action(SR_SUSPEND); 3886 int status = pthread_kill(osthread->pthread_id(), SR_signum); 3887 assert_status(status == 0, status, "pthread_kill"); 3888 3889 // check status and wait until notified of suspension 3890 if (status == 0) { 3891 for (int i = 0; !osthread->sr.is_suspended(); i++) { 3892 os::yield_all(i); 3893 } 3894 osthread->sr.set_suspend_action(SR_NONE); 3895 return true; 3896 } 3897 else { 3898 osthread->sr.set_suspend_action(SR_NONE); 3899 return false; 3900 } 3901} 3902 3903static void do_resume(OSThread* osthread) { 3904 assert(osthread->sr.is_suspended(), "thread should be suspended"); 3905 osthread->sr.set_suspend_action(SR_CONTINUE); 3906 3907 int status = pthread_kill(osthread->pthread_id(), SR_signum); 3908 assert_status(status == 0, status, "pthread_kill"); 3909 // check status and wait unit notified of resumption 3910 if (status == 0) { 3911 for (int i = 0; osthread->sr.is_suspended(); i++) { 3912 os::yield_all(i); 3913 } 3914 } 3915 osthread->sr.set_suspend_action(SR_NONE); 3916} 3917 3918//////////////////////////////////////////////////////////////////////////////// 3919// interrupt support 3920 3921void os::interrupt(Thread* thread) { 3922 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3923 "possibility of dangling Thread pointer"); 3924 3925 OSThread* osthread = thread->osthread(); 3926 3927 if (!osthread->interrupted()) { 3928 osthread->set_interrupted(true); 3929 // More than one thread can get here with the same value of osthread, 3930 // resulting in multiple notifications. We do, however, want the store 3931 // to interrupted() to be visible to other threads before we execute unpark(). 3932 OrderAccess::fence(); 3933 ParkEvent * const slp = thread->_SleepEvent ; 3934 if (slp != NULL) slp->unpark() ; 3935 } 3936 3937 // For JSR166. Unpark even if interrupt status already was set 3938 if (thread->is_Java_thread()) 3939 ((JavaThread*)thread)->parker()->unpark(); 3940 3941 ParkEvent * ev = thread->_ParkEvent ; 3942 if (ev != NULL) ev->unpark() ; 3943 3944} 3945 3946bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 3947 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 3948 "possibility of dangling Thread pointer"); 3949 3950 OSThread* osthread = thread->osthread(); 3951 3952 bool interrupted = osthread->interrupted(); 3953 3954 if (interrupted && clear_interrupted) { 3955 osthread->set_interrupted(false); 3956 // consider thread->_SleepEvent->reset() ... optional optimization 3957 } 3958 3959 return interrupted; 3960} 3961 3962/////////////////////////////////////////////////////////////////////////////////// 3963// signal handling (except suspend/resume) 3964 3965// This routine may be used by user applications as a "hook" to catch signals. 3966// The user-defined signal handler must pass unrecognized signals to this 3967// routine, and if it returns true (non-zero), then the signal handler must 3968// return immediately. If the flag "abort_if_unrecognized" is true, then this 3969// routine will never retun false (zero), but instead will execute a VM panic 3970// routine kill the process. 3971// 3972// If this routine returns false, it is OK to call it again. This allows 3973// the user-defined signal handler to perform checks either before or after 3974// the VM performs its own checks. Naturally, the user code would be making 3975// a serious error if it tried to handle an exception (such as a null check 3976// or breakpoint) that the VM was generating for its own correct operation. 3977// 3978// This routine may recognize any of the following kinds of signals: 3979// SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. 3980// It should be consulted by handlers for any of those signals. 3981// 3982// The caller of this routine must pass in the three arguments supplied 3983// to the function referred to in the "sa_sigaction" (not the "sa_handler") 3984// field of the structure passed to sigaction(). This routine assumes that 3985// the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. 3986// 3987// Note that the VM will print warnings if it detects conflicting signal 3988// handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". 3989// 3990extern "C" JNIEXPORT int 3991JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, 3992 void* ucontext, int abort_if_unrecognized); 3993 3994void signalHandler(int sig, siginfo_t* info, void* uc) { 3995 assert(info != NULL && uc != NULL, "it must be old kernel"); 3996 JVM_handle_bsd_signal(sig, info, uc, true); 3997} 3998 3999 4000// This boolean allows users to forward their own non-matching signals 4001// to JVM_handle_bsd_signal, harmlessly. 4002bool os::Bsd::signal_handlers_are_installed = false; 4003 4004// For signal-chaining 4005struct sigaction os::Bsd::sigact[MAXSIGNUM]; 4006unsigned int os::Bsd::sigs = 0; 4007bool os::Bsd::libjsig_is_loaded = false; 4008typedef struct sigaction *(*get_signal_t)(int); 4009get_signal_t os::Bsd::get_signal_action = NULL; 4010 4011struct sigaction* os::Bsd::get_chained_signal_action(int sig) { 4012 struct sigaction *actp = NULL; 4013 4014 if (libjsig_is_loaded) { 4015 // Retrieve the old signal handler from libjsig 4016 actp = (*get_signal_action)(sig); 4017 } 4018 if (actp == NULL) { 4019 // Retrieve the preinstalled signal handler from jvm 4020 actp = get_preinstalled_handler(sig); 4021 } 4022 4023 return actp; 4024} 4025 4026static bool call_chained_handler(struct sigaction *actp, int sig, 4027 siginfo_t *siginfo, void *context) { 4028 // Call the old signal handler 4029 if (actp->sa_handler == SIG_DFL) { 4030 // It's more reasonable to let jvm treat it as an unexpected exception 4031 // instead of taking the default action. 4032 return false; 4033 } else if (actp->sa_handler != SIG_IGN) { 4034 if ((actp->sa_flags & SA_NODEFER) == 0) { 4035 // automaticlly block the signal 4036 sigaddset(&(actp->sa_mask), sig); 4037 } 4038 4039 sa_handler_t hand; 4040 sa_sigaction_t sa; 4041 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; 4042 // retrieve the chained handler 4043 if (siginfo_flag_set) { 4044 sa = actp->sa_sigaction; 4045 } else { 4046 hand = actp->sa_handler; 4047 } 4048 4049 if ((actp->sa_flags & SA_RESETHAND) != 0) { 4050 actp->sa_handler = SIG_DFL; 4051 } 4052 4053 // try to honor the signal mask 4054 sigset_t oset; 4055 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); 4056 4057 // call into the chained handler 4058 if (siginfo_flag_set) { 4059 (*sa)(sig, siginfo, context); 4060 } else { 4061 (*hand)(sig); 4062 } 4063 4064 // restore the signal mask 4065 pthread_sigmask(SIG_SETMASK, &oset, 0); 4066 } 4067 // Tell jvm's signal handler the signal is taken care of. 4068 return true; 4069} 4070 4071bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { 4072 bool chained = false; 4073 // signal-chaining 4074 if (UseSignalChaining) { 4075 struct sigaction *actp = get_chained_signal_action(sig); 4076 if (actp != NULL) { 4077 chained = call_chained_handler(actp, sig, siginfo, context); 4078 } 4079 } 4080 return chained; 4081} 4082 4083struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { 4084 if ((( (unsigned int)1 << sig ) & sigs) != 0) { 4085 return &sigact[sig]; 4086 } 4087 return NULL; 4088} 4089 4090void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { 4091 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4092 sigact[sig] = oldAct; 4093 sigs |= (unsigned int)1 << sig; 4094} 4095 4096// for diagnostic 4097int os::Bsd::sigflags[MAXSIGNUM]; 4098 4099int os::Bsd::get_our_sigflags(int sig) { 4100 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4101 return sigflags[sig]; 4102} 4103 4104void os::Bsd::set_our_sigflags(int sig, int flags) { 4105 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4106 sigflags[sig] = flags; 4107} 4108 4109void os::Bsd::set_signal_handler(int sig, bool set_installed) { 4110 // Check for overwrite. 4111 struct sigaction oldAct; 4112 sigaction(sig, (struct sigaction*)NULL, &oldAct); 4113 4114 void* oldhand = oldAct.sa_sigaction 4115 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 4116 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 4117 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && 4118 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && 4119 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { 4120 if (AllowUserSignalHandlers || !set_installed) { 4121 // Do not overwrite; user takes responsibility to forward to us. 4122 return; 4123 } else if (UseSignalChaining) { 4124 // save the old handler in jvm 4125 save_preinstalled_handler(sig, oldAct); 4126 // libjsig also interposes the sigaction() call below and saves the 4127 // old sigaction on it own. 4128 } else { 4129 fatal(err_msg("Encountered unexpected pre-existing sigaction handler " 4130 "%#lx for signal %d.", (long)oldhand, sig)); 4131 } 4132 } 4133 4134 struct sigaction sigAct; 4135 sigfillset(&(sigAct.sa_mask)); 4136 sigAct.sa_handler = SIG_DFL; 4137 if (!set_installed) { 4138 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 4139 } else { 4140 sigAct.sa_sigaction = signalHandler; 4141 sigAct.sa_flags = SA_SIGINFO|SA_RESTART; 4142 } 4143 // Save flags, which are set by ours 4144 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); 4145 sigflags[sig] = sigAct.sa_flags; 4146 4147 int ret = sigaction(sig, &sigAct, &oldAct); 4148 assert(ret == 0, "check"); 4149 4150 void* oldhand2 = oldAct.sa_sigaction 4151 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 4152 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 4153 assert(oldhand2 == oldhand, "no concurrent signal handler installation"); 4154} 4155 4156// install signal handlers for signals that HotSpot needs to 4157// handle in order to support Java-level exception handling. 4158 4159void os::Bsd::install_signal_handlers() { 4160 if (!signal_handlers_are_installed) { 4161 signal_handlers_are_installed = true; 4162 4163 // signal-chaining 4164 typedef void (*signal_setting_t)(); 4165 signal_setting_t begin_signal_setting = NULL; 4166 signal_setting_t end_signal_setting = NULL; 4167 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 4168 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); 4169 if (begin_signal_setting != NULL) { 4170 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, 4171 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); 4172 get_signal_action = CAST_TO_FN_PTR(get_signal_t, 4173 dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); 4174 libjsig_is_loaded = true; 4175 assert(UseSignalChaining, "should enable signal-chaining"); 4176 } 4177 if (libjsig_is_loaded) { 4178 // Tell libjsig jvm is setting signal handlers 4179 (*begin_signal_setting)(); 4180 } 4181 4182 set_signal_handler(SIGSEGV, true); 4183 set_signal_handler(SIGPIPE, true); 4184 set_signal_handler(SIGBUS, true); 4185 set_signal_handler(SIGILL, true); 4186 set_signal_handler(SIGFPE, true); 4187 set_signal_handler(SIGXFSZ, true); 4188 4189#if defined(__APPLE__) 4190 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including 4191 // signals caught and handled by the JVM. To work around this, we reset the mach task 4192 // signal handler that's placed on our process by CrashReporter. This disables 4193 // CrashReporter-based reporting. 4194 // 4195 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes 4196 // on caught fatal signals. 4197 // 4198 // Additionally, gdb installs both standard BSD signal handlers, and mach exception 4199 // handlers. By replacing the existing task exception handler, we disable gdb's mach 4200 // exception handling, while leaving the standard BSD signal handlers functional. 4201 kern_return_t kr; 4202 kr = task_set_exception_ports(mach_task_self(), 4203 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, 4204 MACH_PORT_NULL, 4205 EXCEPTION_STATE_IDENTITY, 4206 MACHINE_THREAD_STATE); 4207 4208 assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); 4209#endif 4210 4211 if (libjsig_is_loaded) { 4212 // Tell libjsig jvm finishes setting signal handlers 4213 (*end_signal_setting)(); 4214 } 4215 4216 // We don't activate signal checker if libjsig is in place, we trust ourselves 4217 // and if UserSignalHandler is installed all bets are off 4218 if (CheckJNICalls) { 4219 if (libjsig_is_loaded) { 4220 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); 4221 check_signals = false; 4222 } 4223 if (AllowUserSignalHandlers) { 4224 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); 4225 check_signals = false; 4226 } 4227 } 4228 } 4229} 4230 4231#ifndef _ALLBSD_SOURCE 4232// This is the fastest way to get thread cpu time on Bsd. 4233// Returns cpu time (user+sys) for any thread, not only for current. 4234// POSIX compliant clocks are implemented in the kernels 2.6.16+. 4235// It might work on 2.6.10+ with a special kernel/glibc patch. 4236// For reference, please, see IEEE Std 1003.1-2004: 4237// http://www.unix.org/single_unix_specification 4238 4239jlong os::Bsd::fast_thread_cpu_time(clockid_t clockid) { 4240 struct timespec tp; 4241 int rc = os::Bsd::clock_gettime(clockid, &tp); 4242 assert(rc == 0, "clock_gettime is expected to return 0 code"); 4243 4244 return (tp.tv_sec * NANOSECS_PER_SEC) + tp.tv_nsec; 4245} 4246#endif 4247 4248///// 4249// glibc on Bsd platform uses non-documented flag 4250// to indicate, that some special sort of signal 4251// trampoline is used. 4252// We will never set this flag, and we should 4253// ignore this flag in our diagnostic 4254#ifdef SIGNIFICANT_SIGNAL_MASK 4255#undef SIGNIFICANT_SIGNAL_MASK 4256#endif 4257#define SIGNIFICANT_SIGNAL_MASK (~0x04000000) 4258 4259static const char* get_signal_handler_name(address handler, 4260 char* buf, int buflen) { 4261 int offset; 4262 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); 4263 if (found) { 4264 // skip directory names 4265 const char *p1, *p2; 4266 p1 = buf; 4267 size_t len = strlen(os::file_separator()); 4268 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 4269 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); 4270 } else { 4271 jio_snprintf(buf, buflen, PTR_FORMAT, handler); 4272 } 4273 return buf; 4274} 4275 4276static void print_signal_handler(outputStream* st, int sig, 4277 char* buf, size_t buflen) { 4278 struct sigaction sa; 4279 4280 sigaction(sig, NULL, &sa); 4281 4282 // See comment for SIGNIFICANT_SIGNAL_MASK define 4283 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 4284 4285 st->print("%s: ", os::exception_name(sig, buf, buflen)); 4286 4287 address handler = (sa.sa_flags & SA_SIGINFO) 4288 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 4289 : CAST_FROM_FN_PTR(address, sa.sa_handler); 4290 4291 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { 4292 st->print("SIG_DFL"); 4293 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { 4294 st->print("SIG_IGN"); 4295 } else { 4296 st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); 4297 } 4298 4299 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask); 4300 4301 address rh = VMError::get_resetted_sighandler(sig); 4302 // May be, handler was resetted by VMError? 4303 if(rh != NULL) { 4304 handler = rh; 4305 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; 4306 } 4307 4308 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags); 4309 4310 // Check: is it our handler? 4311 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || 4312 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { 4313 // It is our signal handler 4314 // check for flags, reset system-used one! 4315 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { 4316 st->print( 4317 ", flags was changed from " PTR32_FORMAT ", consider using jsig library", 4318 os::Bsd::get_our_sigflags(sig)); 4319 } 4320 } 4321 st->cr(); 4322} 4323 4324 4325#define DO_SIGNAL_CHECK(sig) \ 4326 if (!sigismember(&check_signal_done, sig)) \ 4327 os::Bsd::check_signal_handler(sig) 4328 4329// This method is a periodic task to check for misbehaving JNI applications 4330// under CheckJNI, we can add any periodic checks here 4331 4332void os::run_periodic_checks() { 4333 4334 if (check_signals == false) return; 4335 4336 // SEGV and BUS if overridden could potentially prevent 4337 // generation of hs*.log in the event of a crash, debugging 4338 // such a case can be very challenging, so we absolutely 4339 // check the following for a good measure: 4340 DO_SIGNAL_CHECK(SIGSEGV); 4341 DO_SIGNAL_CHECK(SIGILL); 4342 DO_SIGNAL_CHECK(SIGFPE); 4343 DO_SIGNAL_CHECK(SIGBUS); 4344 DO_SIGNAL_CHECK(SIGPIPE); 4345 DO_SIGNAL_CHECK(SIGXFSZ); 4346 4347 4348 // ReduceSignalUsage allows the user to override these handlers 4349 // see comments at the very top and jvm_solaris.h 4350 if (!ReduceSignalUsage) { 4351 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); 4352 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); 4353 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); 4354 DO_SIGNAL_CHECK(BREAK_SIGNAL); 4355 } 4356 4357 DO_SIGNAL_CHECK(SR_signum); 4358 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); 4359} 4360 4361typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); 4362 4363static os_sigaction_t os_sigaction = NULL; 4364 4365void os::Bsd::check_signal_handler(int sig) { 4366 char buf[O_BUFLEN]; 4367 address jvmHandler = NULL; 4368 4369 4370 struct sigaction act; 4371 if (os_sigaction == NULL) { 4372 // only trust the default sigaction, in case it has been interposed 4373 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); 4374 if (os_sigaction == NULL) return; 4375 } 4376 4377 os_sigaction(sig, (struct sigaction*)NULL, &act); 4378 4379 4380 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; 4381 4382 address thisHandler = (act.sa_flags & SA_SIGINFO) 4383 ? CAST_FROM_FN_PTR(address, act.sa_sigaction) 4384 : CAST_FROM_FN_PTR(address, act.sa_handler) ; 4385 4386 4387 switch(sig) { 4388 case SIGSEGV: 4389 case SIGBUS: 4390 case SIGFPE: 4391 case SIGPIPE: 4392 case SIGILL: 4393 case SIGXFSZ: 4394 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); 4395 break; 4396 4397 case SHUTDOWN1_SIGNAL: 4398 case SHUTDOWN2_SIGNAL: 4399 case SHUTDOWN3_SIGNAL: 4400 case BREAK_SIGNAL: 4401 jvmHandler = (address)user_handler(); 4402 break; 4403 4404 case INTERRUPT_SIGNAL: 4405 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); 4406 break; 4407 4408 default: 4409 if (sig == SR_signum) { 4410 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); 4411 } else { 4412 return; 4413 } 4414 break; 4415 } 4416 4417 if (thisHandler != jvmHandler) { 4418 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); 4419 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); 4420 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); 4421 // No need to check this sig any longer 4422 sigaddset(&check_signal_done, sig); 4423 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { 4424 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); 4425 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); 4426 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); 4427 // No need to check this sig any longer 4428 sigaddset(&check_signal_done, sig); 4429 } 4430 4431 // Dump all the signal 4432 if (sigismember(&check_signal_done, sig)) { 4433 print_signal_handlers(tty, buf, O_BUFLEN); 4434 } 4435} 4436 4437extern void report_error(char* file_name, int line_no, char* title, char* format, ...); 4438 4439extern bool signal_name(int signo, char* buf, size_t len); 4440 4441const char* os::exception_name(int exception_code, char* buf, size_t size) { 4442 if (0 < exception_code && exception_code <= SIGRTMAX) { 4443 // signal 4444 if (!signal_name(exception_code, buf, size)) { 4445 jio_snprintf(buf, size, "SIG%d", exception_code); 4446 } 4447 return buf; 4448 } else { 4449 return NULL; 4450 } 4451} 4452 4453// this is called _before_ the most of global arguments have been parsed 4454void os::init(void) { 4455 char dummy; /* used to get a guess on initial stack address */ 4456// first_hrtime = gethrtime(); 4457 4458 // With BsdThreads the JavaMain thread pid (primordial thread) 4459 // is different than the pid of the java launcher thread. 4460 // So, on Bsd, the launcher thread pid is passed to the VM 4461 // via the sun.java.launcher.pid property. 4462 // Use this property instead of getpid() if it was correctly passed. 4463 // See bug 6351349. 4464 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); 4465 4466 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); 4467 4468 clock_tics_per_sec = CLK_TCK; 4469 4470 init_random(1234567); 4471 4472 ThreadCritical::initialize(); 4473 4474 Bsd::set_page_size(getpagesize()); 4475 if (Bsd::page_size() == -1) { 4476 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", 4477 strerror(errno))); 4478 } 4479 init_page_sizes((size_t) Bsd::page_size()); 4480 4481 Bsd::initialize_system_info(); 4482 4483 // main_thread points to the aboriginal thread 4484 Bsd::_main_thread = pthread_self(); 4485 4486 Bsd::clock_init(); 4487 initial_time_count = os::elapsed_counter(); 4488 4489#ifdef __APPLE__ 4490 // XXXDARWIN 4491 // Work around the unaligned VM callbacks in hotspot's 4492 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on 4493 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces 4494 // alignment when doing symbol lookup. To work around this, we force early 4495 // binding of all symbols now, thus binding when alignment is known-good. 4496 _dyld_bind_fully_image_containing_address((const void *) &os::init); 4497#endif 4498} 4499 4500// To install functions for atexit system call 4501extern "C" { 4502 static void perfMemory_exit_helper() { 4503 perfMemory_exit(); 4504 } 4505} 4506 4507// this is called _after_ the global arguments have been parsed 4508jint os::init_2(void) 4509{ 4510#ifndef _ALLBSD_SOURCE 4511 Bsd::fast_thread_clock_init(); 4512#endif 4513 4514 // Allocate a single page and mark it as readable for safepoint polling 4515 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 4516 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" ); 4517 4518 os::set_polling_page( polling_page ); 4519 4520#ifndef PRODUCT 4521 if(Verbose && PrintMiscellaneous) 4522 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); 4523#endif 4524 4525 if (!UseMembar) { 4526 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); 4527 guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page"); 4528 os::set_memory_serialize_page( mem_serialize_page ); 4529 4530#ifndef PRODUCT 4531 if(Verbose && PrintMiscellaneous) 4532 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); 4533#endif 4534 } 4535 4536 os::large_page_init(); 4537 4538 // initialize suspend/resume support - must do this before signal_sets_init() 4539 if (SR_initialize() != 0) { 4540 perror("SR_initialize failed"); 4541 return JNI_ERR; 4542 } 4543 4544 Bsd::signal_sets_init(); 4545 Bsd::install_signal_handlers(); 4546 4547 // Check minimum allowable stack size for thread creation and to initialize 4548 // the java system classes, including StackOverflowError - depends on page 4549 // size. Add a page for compiler2 recursion in main thread. 4550 // Add in 2*BytesPerWord times page size to account for VM stack during 4551 // class initialization depending on 32 or 64 bit VM. 4552 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, 4553 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 4554 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); 4555 4556 size_t threadStackSizeInBytes = ThreadStackSize * K; 4557 if (threadStackSizeInBytes != 0 && 4558 threadStackSizeInBytes < os::Bsd::min_stack_allowed) { 4559 tty->print_cr("\nThe stack size specified is too small, " 4560 "Specify at least %dk", 4561 os::Bsd::min_stack_allowed/ K); 4562 return JNI_ERR; 4563 } 4564 4565 // Make the stack size a multiple of the page size so that 4566 // the yellow/red zones can be guarded. 4567 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, 4568 vm_page_size())); 4569 4570#ifndef _ALLBSD_SOURCE 4571 Bsd::capture_initial_stack(JavaThread::stack_size_at_create()); 4572 4573 Bsd::libpthread_init(); 4574 if (PrintMiscellaneous && (Verbose || WizardMode)) { 4575 tty->print_cr("[HotSpot is running with %s, %s(%s)]\n", 4576 Bsd::glibc_version(), Bsd::libpthread_version(), 4577 Bsd::is_floating_stack() ? "floating stack" : "fixed stack"); 4578 } 4579 4580 if (UseNUMA) { 4581 if (!Bsd::libnuma_init()) { 4582 UseNUMA = false; 4583 } else { 4584 if ((Bsd::numa_max_node() < 1)) { 4585 // There's only one node(they start from 0), disable NUMA. 4586 UseNUMA = false; 4587 } 4588 } 4589 // With SHM large pages we cannot uncommit a page, so there's not way 4590 // we can make the adaptive lgrp chunk resizing work. If the user specified 4591 // both UseNUMA and UseLargePages (or UseSHM) on the command line - warn and 4592 // disable adaptive resizing. 4593 if (UseNUMA && UseLargePages && UseSHM) { 4594 if (!FLAG_IS_DEFAULT(UseNUMA)) { 4595 if (FLAG_IS_DEFAULT(UseLargePages) && FLAG_IS_DEFAULT(UseSHM)) { 4596 UseLargePages = false; 4597 } else { 4598 warning("UseNUMA is not fully compatible with SHM large pages, disabling adaptive resizing"); 4599 UseAdaptiveSizePolicy = false; 4600 UseAdaptiveNUMAChunkSizing = false; 4601 } 4602 } else { 4603 UseNUMA = false; 4604 } 4605 } 4606 if (!UseNUMA && ForceNUMA) { 4607 UseNUMA = true; 4608 } 4609 } 4610#endif 4611 4612 if (MaxFDLimit) { 4613 // set the number of file descriptors to max. print out error 4614 // if getrlimit/setrlimit fails but continue regardless. 4615 struct rlimit nbr_files; 4616 int status = getrlimit(RLIMIT_NOFILE, &nbr_files); 4617 if (status != 0) { 4618 if (PrintMiscellaneous && (Verbose || WizardMode)) 4619 perror("os::init_2 getrlimit failed"); 4620 } else { 4621 nbr_files.rlim_cur = nbr_files.rlim_max; 4622 4623#ifdef __APPLE__ 4624 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if 4625 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must 4626 // be used instead 4627 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); 4628#endif 4629 4630 status = setrlimit(RLIMIT_NOFILE, &nbr_files); 4631 if (status != 0) { 4632 if (PrintMiscellaneous && (Verbose || WizardMode)) 4633 perror("os::init_2 setrlimit failed"); 4634 } 4635 } 4636 } 4637 4638#ifndef _ALLBSD_SOURCE 4639 // Initialize lock used to serialize thread creation (see os::create_thread) 4640 Bsd::set_createThread_lock(new Mutex(Mutex::leaf, "createThread_lock", false)); 4641#endif 4642 4643 // at-exit methods are called in the reverse order of their registration. 4644 // atexit functions are called on return from main or as a result of a 4645 // call to exit(3C). There can be only 32 of these functions registered 4646 // and atexit() does not set errno. 4647 4648 if (PerfAllowAtExitRegistration) { 4649 // only register atexit functions if PerfAllowAtExitRegistration is set. 4650 // atexit functions can be delayed until process exit time, which 4651 // can be problematic for embedded VM situations. Embedded VMs should 4652 // call DestroyJavaVM() to assure that VM resources are released. 4653 4654 // note: perfMemory_exit_helper atexit function may be removed in 4655 // the future if the appropriate cleanup code can be added to the 4656 // VM_Exit VMOperation's doit method. 4657 if (atexit(perfMemory_exit_helper) != 0) { 4658 warning("os::init2 atexit(perfMemory_exit_helper) failed"); 4659 } 4660 } 4661 4662 // initialize thread priority policy 4663 prio_init(); 4664 4665#ifdef __APPLE__ 4666 // dynamically link to objective c gc registration 4667 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); 4668 if (handleLibObjc != NULL) { 4669 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); 4670 } 4671#endif 4672 4673 return JNI_OK; 4674} 4675 4676// this is called at the end of vm_initialization 4677void os::init_3(void) { } 4678 4679// Mark the polling page as unreadable 4680void os::make_polling_page_unreadable(void) { 4681 if( !guard_memory((char*)_polling_page, Bsd::page_size()) ) 4682 fatal("Could not disable polling page"); 4683}; 4684 4685// Mark the polling page as readable 4686void os::make_polling_page_readable(void) { 4687 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { 4688 fatal("Could not enable polling page"); 4689 } 4690}; 4691 4692int os::active_processor_count() { 4693#ifdef _ALLBSD_SOURCE 4694 return _processor_count; 4695#else 4696 // Bsd doesn't yet have a (official) notion of processor sets, 4697 // so just return the number of online processors. 4698 int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN); 4699 assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check"); 4700 return online_cpus; 4701#endif 4702} 4703 4704void os::set_native_thread_name(const char *name) { 4705#if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 4706 // This is only supported in Snow Leopard and beyond 4707 if (name != NULL) { 4708 // Add a "Java: " prefix to the name 4709 char buf[MAXTHREADNAMESIZE]; 4710 snprintf(buf, sizeof(buf), "Java: %s", name); 4711 pthread_setname_np(buf); 4712 } 4713#endif 4714} 4715 4716bool os::distribute_processes(uint length, uint* distribution) { 4717 // Not yet implemented. 4718 return false; 4719} 4720 4721bool os::bind_to_processor(uint processor_id) { 4722 // Not yet implemented. 4723 return false; 4724} 4725 4726/// 4727 4728// Suspends the target using the signal mechanism and then grabs the PC before 4729// resuming the target. Used by the flat-profiler only 4730ExtendedPC os::get_thread_pc(Thread* thread) { 4731 // Make sure that it is called by the watcher for the VMThread 4732 assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); 4733 assert(thread->is_VM_thread(), "Can only be called for VMThread"); 4734 4735 ExtendedPC epc; 4736 4737 OSThread* osthread = thread->osthread(); 4738 if (do_suspend(osthread)) { 4739 if (osthread->ucontext() != NULL) { 4740 epc = os::Bsd::ucontext_get_pc(osthread->ucontext()); 4741 } else { 4742 // NULL context is unexpected, double-check this is the VMThread 4743 guarantee(thread->is_VM_thread(), "can only be called for VMThread"); 4744 } 4745 do_resume(osthread); 4746 } 4747 // failure means pthread_kill failed for some reason - arguably this is 4748 // a fatal problem, but such problems are ignored elsewhere 4749 4750 return epc; 4751} 4752 4753int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) 4754{ 4755#ifdef _ALLBSD_SOURCE 4756 return pthread_cond_timedwait(_cond, _mutex, _abstime); 4757#else 4758 if (is_NPTL()) { 4759 return pthread_cond_timedwait(_cond, _mutex, _abstime); 4760 } else { 4761#ifndef IA64 4762 // 6292965: BsdThreads pthread_cond_timedwait() resets FPU control 4763 // word back to default 64bit precision if condvar is signaled. Java 4764 // wants 53bit precision. Save and restore current value. 4765 int fpu = get_fpu_control_word(); 4766#endif // IA64 4767 int status = pthread_cond_timedwait(_cond, _mutex, _abstime); 4768#ifndef IA64 4769 set_fpu_control_word(fpu); 4770#endif // IA64 4771 return status; 4772 } 4773#endif 4774} 4775 4776//////////////////////////////////////////////////////////////////////////////// 4777// debug support 4778 4779static address same_page(address x, address y) { 4780 int page_bits = -os::vm_page_size(); 4781 if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits)) 4782 return x; 4783 else if (x > y) 4784 return (address)(intptr_t(y) | ~page_bits) + 1; 4785 else 4786 return (address)(intptr_t(y) & page_bits); 4787} 4788 4789bool os::find(address addr, outputStream* st) { 4790 Dl_info dlinfo; 4791 memset(&dlinfo, 0, sizeof(dlinfo)); 4792 if (dladdr(addr, &dlinfo)) { 4793 st->print(PTR_FORMAT ": ", addr); 4794 if (dlinfo.dli_sname != NULL) { 4795 st->print("%s+%#x", dlinfo.dli_sname, 4796 addr - (intptr_t)dlinfo.dli_saddr); 4797 } else if (dlinfo.dli_fname) { 4798 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase); 4799 } else { 4800 st->print("<absolute address>"); 4801 } 4802 if (dlinfo.dli_fname) { 4803 st->print(" in %s", dlinfo.dli_fname); 4804 } 4805 if (dlinfo.dli_fbase) { 4806 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); 4807 } 4808 st->cr(); 4809 4810 if (Verbose) { 4811 // decode some bytes around the PC 4812 address begin = same_page(addr-40, addr); 4813 address end = same_page(addr+40, addr); 4814 address lowest = (address) dlinfo.dli_sname; 4815 if (!lowest) lowest = (address) dlinfo.dli_fbase; 4816 if (begin < lowest) begin = lowest; 4817 Dl_info dlinfo2; 4818 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr 4819 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) 4820 end = (address) dlinfo2.dli_saddr; 4821 Disassembler::decode(begin, end, st); 4822 } 4823 return true; 4824 } 4825 return false; 4826} 4827 4828//////////////////////////////////////////////////////////////////////////////// 4829// misc 4830 4831// This does not do anything on Bsd. This is basically a hook for being 4832// able to use structured exception handling (thread-local exception filters) 4833// on, e.g., Win32. 4834void 4835os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, 4836 JavaCallArguments* args, Thread* thread) { 4837 f(value, method, args, thread); 4838} 4839 4840void os::print_statistics() { 4841} 4842 4843int os::message_box(const char* title, const char* message) { 4844 int i; 4845 fdStream err(defaultStream::error_fd()); 4846 for (i = 0; i < 78; i++) err.print_raw("="); 4847 err.cr(); 4848 err.print_raw_cr(title); 4849 for (i = 0; i < 78; i++) err.print_raw("-"); 4850 err.cr(); 4851 err.print_raw_cr(message); 4852 for (i = 0; i < 78; i++) err.print_raw("="); 4853 err.cr(); 4854 4855 char buf[16]; 4856 // Prevent process from exiting upon "read error" without consuming all CPU 4857 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } 4858 4859 return buf[0] == 'y' || buf[0] == 'Y'; 4860} 4861 4862int os::stat(const char *path, struct stat *sbuf) { 4863 char pathbuf[MAX_PATH]; 4864 if (strlen(path) > MAX_PATH - 1) { 4865 errno = ENAMETOOLONG; 4866 return -1; 4867 } 4868 os::native_path(strcpy(pathbuf, path)); 4869 return ::stat(pathbuf, sbuf); 4870} 4871 4872bool os::check_heap(bool force) { 4873 return true; 4874} 4875 4876int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { 4877 return ::vsnprintf(buf, count, format, args); 4878} 4879 4880// Is a (classpath) directory empty? 4881bool os::dir_is_empty(const char* path) { 4882 DIR *dir = NULL; 4883 struct dirent *ptr; 4884 4885 dir = opendir(path); 4886 if (dir == NULL) return true; 4887 4888 /* Scan the directory */ 4889 bool result = true; 4890 char buf[sizeof(struct dirent) + MAX_PATH]; 4891 while (result && (ptr = ::readdir(dir)) != NULL) { 4892 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { 4893 result = false; 4894 } 4895 } 4896 closedir(dir); 4897 return result; 4898} 4899 4900// This code originates from JDK's sysOpen and open64_w 4901// from src/solaris/hpi/src/system_md.c 4902 4903#ifndef O_DELETE 4904#define O_DELETE 0x10000 4905#endif 4906 4907// Open a file. Unlink the file immediately after open returns 4908// if the specified oflag has the O_DELETE flag set. 4909// O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c 4910 4911int os::open(const char *path, int oflag, int mode) { 4912 4913 if (strlen(path) > MAX_PATH - 1) { 4914 errno = ENAMETOOLONG; 4915 return -1; 4916 } 4917 int fd; 4918 int o_delete = (oflag & O_DELETE); 4919 oflag = oflag & ~O_DELETE; 4920 4921 fd = ::open(path, oflag, mode); 4922 if (fd == -1) return -1; 4923 4924 //If the open succeeded, the file might still be a directory 4925 { 4926 struct stat buf; 4927 int ret = ::fstat(fd, &buf); 4928 int st_mode = buf.st_mode; 4929 4930 if (ret != -1) { 4931 if ((st_mode & S_IFMT) == S_IFDIR) { 4932 errno = EISDIR; 4933 ::close(fd); 4934 return -1; 4935 } 4936 } else { 4937 ::close(fd); 4938 return -1; 4939 } 4940 } 4941 4942 /* 4943 * All file descriptors that are opened in the JVM and not 4944 * specifically destined for a subprocess should have the 4945 * close-on-exec flag set. If we don't set it, then careless 3rd 4946 * party native code might fork and exec without closing all 4947 * appropriate file descriptors (e.g. as we do in closeDescriptors in 4948 * UNIXProcess.c), and this in turn might: 4949 * 4950 * - cause end-of-file to fail to be detected on some file 4951 * descriptors, resulting in mysterious hangs, or 4952 * 4953 * - might cause an fopen in the subprocess to fail on a system 4954 * suffering from bug 1085341. 4955 * 4956 * (Yes, the default setting of the close-on-exec flag is a Unix 4957 * design flaw) 4958 * 4959 * See: 4960 * 1085341: 32-bit stdio routines should support file descriptors >255 4961 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed 4962 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 4963 */ 4964#ifdef FD_CLOEXEC 4965 { 4966 int flags = ::fcntl(fd, F_GETFD); 4967 if (flags != -1) 4968 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 4969 } 4970#endif 4971 4972 if (o_delete != 0) { 4973 ::unlink(path); 4974 } 4975 return fd; 4976} 4977 4978 4979// create binary file, rewriting existing file if required 4980int os::create_binary_file(const char* path, bool rewrite_existing) { 4981 int oflags = O_WRONLY | O_CREAT; 4982 if (!rewrite_existing) { 4983 oflags |= O_EXCL; 4984 } 4985 return ::open(path, oflags, S_IREAD | S_IWRITE); 4986} 4987 4988// return current position of file pointer 4989jlong os::current_file_offset(int fd) { 4990 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); 4991} 4992 4993// move file pointer to the specified offset 4994jlong os::seek_to_file_offset(int fd, jlong offset) { 4995 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); 4996} 4997 4998// This code originates from JDK's sysAvailable 4999// from src/solaris/hpi/src/native_threads/src/sys_api_td.c 5000 5001int os::available(int fd, jlong *bytes) { 5002 jlong cur, end; 5003 int mode; 5004 struct stat buf; 5005 5006 if (::fstat(fd, &buf) >= 0) { 5007 mode = buf.st_mode; 5008 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { 5009 /* 5010 * XXX: is the following call interruptible? If so, this might 5011 * need to go through the INTERRUPT_IO() wrapper as for other 5012 * blocking, interruptible calls in this file. 5013 */ 5014 int n; 5015 if (::ioctl(fd, FIONREAD, &n) >= 0) { 5016 *bytes = n; 5017 return 1; 5018 } 5019 } 5020 } 5021 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { 5022 return 0; 5023 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { 5024 return 0; 5025 } else if (::lseek(fd, cur, SEEK_SET) == -1) { 5026 return 0; 5027 } 5028 *bytes = end - cur; 5029 return 1; 5030} 5031 5032int os::socket_available(int fd, jint *pbytes) { 5033 if (fd < 0) 5034 return OS_OK; 5035 5036 int ret; 5037 5038 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); 5039 5040 //%% note ioctl can return 0 when successful, JVM_SocketAvailable 5041 // is expected to return 0 on failure and 1 on success to the jdk. 5042 5043 return (ret == OS_ERR) ? 0 : 1; 5044} 5045 5046// Map a block of memory. 5047char* os::map_memory(int fd, const char* file_name, size_t file_offset, 5048 char *addr, size_t bytes, bool read_only, 5049 bool allow_exec) { 5050 int prot; 5051 int flags; 5052 5053 if (read_only) { 5054 prot = PROT_READ; 5055 flags = MAP_SHARED; 5056 } else { 5057 prot = PROT_READ | PROT_WRITE; 5058 flags = MAP_PRIVATE; 5059 } 5060 5061 if (allow_exec) { 5062 prot |= PROT_EXEC; 5063 } 5064 5065 if (addr != NULL) { 5066 flags |= MAP_FIXED; 5067 } 5068 5069 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, 5070 fd, file_offset); 5071 if (mapped_address == MAP_FAILED) { 5072 return NULL; 5073 } 5074 return mapped_address; 5075} 5076 5077 5078// Remap a block of memory. 5079char* os::remap_memory(int fd, const char* file_name, size_t file_offset, 5080 char *addr, size_t bytes, bool read_only, 5081 bool allow_exec) { 5082 // same as map_memory() on this OS 5083 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, 5084 allow_exec); 5085} 5086 5087 5088// Unmap a block of memory. 5089bool os::unmap_memory(char* addr, size_t bytes) { 5090 return munmap(addr, bytes) == 0; 5091} 5092 5093#ifndef _ALLBSD_SOURCE 5094static jlong slow_thread_cpu_time(Thread *thread, bool user_sys_cpu_time); 5095 5096static clockid_t thread_cpu_clockid(Thread* thread) { 5097 pthread_t tid = thread->osthread()->pthread_id(); 5098 clockid_t clockid; 5099 5100 // Get thread clockid 5101 int rc = os::Bsd::pthread_getcpuclockid(tid, &clockid); 5102 assert(rc == 0, "pthread_getcpuclockid is expected to return 0 code"); 5103 return clockid; 5104} 5105#endif 5106 5107// current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) 5108// are used by JVM M&M and JVMTI to get user+sys or user CPU time 5109// of a thread. 5110// 5111// current_thread_cpu_time() and thread_cpu_time(Thread*) returns 5112// the fast estimate available on the platform. 5113 5114jlong os::current_thread_cpu_time() { 5115#ifdef __APPLE__ 5116 return os::thread_cpu_time(Thread::current(), true /* user + sys */); 5117#elif !defined(_ALLBSD_SOURCE) 5118 if (os::Bsd::supports_fast_thread_cpu_time()) { 5119 return os::Bsd::fast_thread_cpu_time(CLOCK_THREAD_CPUTIME_ID); 5120 } else { 5121 // return user + sys since the cost is the same 5122 return slow_thread_cpu_time(Thread::current(), true /* user + sys */); 5123 } 5124#endif 5125} 5126 5127jlong os::thread_cpu_time(Thread* thread) { 5128#ifndef _ALLBSD_SOURCE 5129 // consistent with what current_thread_cpu_time() returns 5130 if (os::Bsd::supports_fast_thread_cpu_time()) { 5131 return os::Bsd::fast_thread_cpu_time(thread_cpu_clockid(thread)); 5132 } else { 5133 return slow_thread_cpu_time(thread, true /* user + sys */); 5134 } 5135#endif 5136} 5137 5138jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { 5139#ifdef __APPLE__ 5140 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); 5141#elif !defined(_ALLBSD_SOURCE) 5142 if (user_sys_cpu_time && os::Bsd::supports_fast_thread_cpu_time()) { 5143 return os::Bsd::fast_thread_cpu_time(CLOCK_THREAD_CPUTIME_ID); 5144 } else { 5145 return slow_thread_cpu_time(Thread::current(), user_sys_cpu_time); 5146 } 5147#endif 5148} 5149 5150jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 5151#ifdef __APPLE__ 5152 struct thread_basic_info tinfo; 5153 mach_msg_type_number_t tcount = THREAD_INFO_MAX; 5154 kern_return_t kr; 5155 mach_port_t mach_thread; 5156 5157 mach_thread = pthread_mach_thread_np(thread->osthread()->thread_id()); 5158 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); 5159 if (kr != KERN_SUCCESS) 5160 return -1; 5161 5162 if (user_sys_cpu_time) { 5163 jlong nanos; 5164 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; 5165 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; 5166 return nanos; 5167 } else { 5168 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); 5169 } 5170#elif !defined(_ALLBSD_SOURCE) 5171 if (user_sys_cpu_time && os::Bsd::supports_fast_thread_cpu_time()) { 5172 return os::Bsd::fast_thread_cpu_time(thread_cpu_clockid(thread)); 5173 } else { 5174 return slow_thread_cpu_time(thread, user_sys_cpu_time); 5175 } 5176#endif 5177} 5178 5179#ifndef _ALLBSD_SOURCE 5180// 5181// -1 on error. 5182// 5183 5184static jlong slow_thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { 5185 static bool proc_pid_cpu_avail = true; 5186 static bool proc_task_unchecked = true; 5187 static const char *proc_stat_path = "/proc/%d/stat"; 5188 pid_t tid = thread->osthread()->thread_id(); 5189 int i; 5190 char *s; 5191 char stat[2048]; 5192 int statlen; 5193 char proc_name[64]; 5194 int count; 5195 long sys_time, user_time; 5196 char string[64]; 5197 char cdummy; 5198 int idummy; 5199 long ldummy; 5200 FILE *fp; 5201 5202 // We first try accessing /proc/<pid>/cpu since this is faster to 5203 // process. If this file is not present (bsd kernels 2.5 and above) 5204 // then we open /proc/<pid>/stat. 5205 if ( proc_pid_cpu_avail ) { 5206 sprintf(proc_name, "/proc/%d/cpu", tid); 5207 fp = fopen(proc_name, "r"); 5208 if ( fp != NULL ) { 5209 count = fscanf( fp, "%s %lu %lu\n", string, &user_time, &sys_time); 5210 fclose(fp); 5211 if ( count != 3 ) return -1; 5212 5213 if (user_sys_cpu_time) { 5214 return ((jlong)sys_time + (jlong)user_time) * (1000000000 / clock_tics_per_sec); 5215 } else { 5216 return (jlong)user_time * (1000000000 / clock_tics_per_sec); 5217 } 5218 } 5219 else proc_pid_cpu_avail = false; 5220 } 5221 5222 // The /proc/<tid>/stat aggregates per-process usage on 5223 // new Bsd kernels 2.6+ where NPTL is supported. 5224 // The /proc/self/task/<tid>/stat still has the per-thread usage. 5225 // See bug 6328462. 5226 // There can be no directory /proc/self/task on kernels 2.4 with NPTL 5227 // and possibly in some other cases, so we check its availability. 5228 if (proc_task_unchecked && os::Bsd::is_NPTL()) { 5229 // This is executed only once 5230 proc_task_unchecked = false; 5231 fp = fopen("/proc/self/task", "r"); 5232 if (fp != NULL) { 5233 proc_stat_path = "/proc/self/task/%d/stat"; 5234 fclose(fp); 5235 } 5236 } 5237 5238 sprintf(proc_name, proc_stat_path, tid); 5239 fp = fopen(proc_name, "r"); 5240 if ( fp == NULL ) return -1; 5241 statlen = fread(stat, 1, 2047, fp); 5242 stat[statlen] = '\0'; 5243 fclose(fp); 5244 5245 // Skip pid and the command string. Note that we could be dealing with 5246 // weird command names, e.g. user could decide to rename java launcher 5247 // to "java 1.4.2 :)", then the stat file would look like 5248 // 1234 (java 1.4.2 :)) R ... ... 5249 // We don't really need to know the command string, just find the last 5250 // occurrence of ")" and then start parsing from there. See bug 4726580. 5251 s = strrchr(stat, ')'); 5252 i = 0; 5253 if (s == NULL ) return -1; 5254 5255 // Skip blank chars 5256 do s++; while (isspace(*s)); 5257 5258 count = sscanf(s,"%c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu", 5259 &cdummy, &idummy, &idummy, &idummy, &idummy, &idummy, 5260 &ldummy, &ldummy, &ldummy, &ldummy, &ldummy, 5261 &user_time, &sys_time); 5262 if ( count != 13 ) return -1; 5263 if (user_sys_cpu_time) { 5264 return ((jlong)sys_time + (jlong)user_time) * (1000000000 / clock_tics_per_sec); 5265 } else { 5266 return (jlong)user_time * (1000000000 / clock_tics_per_sec); 5267 } 5268} 5269#endif 5270 5271void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 5272 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 5273 info_ptr->may_skip_backward = false; // elapsed time not wall time 5274 info_ptr->may_skip_forward = false; // elapsed time not wall time 5275 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 5276} 5277 5278void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { 5279 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits 5280 info_ptr->may_skip_backward = false; // elapsed time not wall time 5281 info_ptr->may_skip_forward = false; // elapsed time not wall time 5282 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned 5283} 5284 5285bool os::is_thread_cpu_time_supported() { 5286#ifdef __APPLE__ 5287 return true; 5288#elif defined(_ALLBSD_SOURCE) 5289 return false; 5290#else 5291 return true; 5292#endif 5293} 5294 5295// System loadavg support. Returns -1 if load average cannot be obtained. 5296// Bsd doesn't yet have a (official) notion of processor sets, 5297// so just return the system wide load average. 5298int os::loadavg(double loadavg[], int nelem) { 5299 return ::getloadavg(loadavg, nelem); 5300} 5301 5302void os::pause() { 5303 char filename[MAX_PATH]; 5304 if (PauseAtStartupFile && PauseAtStartupFile[0]) { 5305 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); 5306 } else { 5307 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); 5308 } 5309 5310 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); 5311 if (fd != -1) { 5312 struct stat buf; 5313 ::close(fd); 5314 while (::stat(filename, &buf) == 0) { 5315 (void)::poll(NULL, 0, 100); 5316 } 5317 } else { 5318 jio_fprintf(stderr, 5319 "Could not open pause file '%s', continuing immediately.\n", filename); 5320 } 5321} 5322 5323 5324// Refer to the comments in os_solaris.cpp park-unpark. 5325// 5326// Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can 5327// hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. 5328// For specifics regarding the bug see GLIBC BUGID 261237 : 5329// http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. 5330// Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future 5331// will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar 5332// is used. (The simple C test-case provided in the GLIBC bug report manifests the 5333// hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() 5334// and monitorenter when we're using 1-0 locking. All those operations may result in 5335// calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version 5336// of libpthread avoids the problem, but isn't practical. 5337// 5338// Possible remedies: 5339// 5340// 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. 5341// This is palliative and probabilistic, however. If the thread is preempted 5342// between the call to compute_abstime() and pthread_cond_timedwait(), more 5343// than the minimum period may have passed, and the abstime may be stale (in the 5344// past) resultin in a hang. Using this technique reduces the odds of a hang 5345// but the JVM is still vulnerable, particularly on heavily loaded systems. 5346// 5347// 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead 5348// of the usual flag-condvar-mutex idiom. The write side of the pipe is set 5349// NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) 5350// reduces to poll()+read(). This works well, but consumes 2 FDs per extant 5351// thread. 5352// 5353// 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread 5354// that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing 5355// a timeout request to the chron thread and then blocking via pthread_cond_wait(). 5356// This also works well. In fact it avoids kernel-level scalability impediments 5357// on certain platforms that don't handle lots of active pthread_cond_timedwait() 5358// timers in a graceful fashion. 5359// 5360// 4. When the abstime value is in the past it appears that control returns 5361// correctly from pthread_cond_timedwait(), but the condvar is left corrupt. 5362// Subsequent timedwait/wait calls may hang indefinitely. Given that, we 5363// can avoid the problem by reinitializing the condvar -- by cond_destroy() 5364// followed by cond_init() -- after all calls to pthread_cond_timedwait(). 5365// It may be possible to avoid reinitialization by checking the return 5366// value from pthread_cond_timedwait(). In addition to reinitializing the 5367// condvar we must establish the invariant that cond_signal() is only called 5368// within critical sections protected by the adjunct mutex. This prevents 5369// cond_signal() from "seeing" a condvar that's in the midst of being 5370// reinitialized or that is corrupt. Sadly, this invariant obviates the 5371// desirable signal-after-unlock optimization that avoids futile context switching. 5372// 5373// I'm also concerned that some versions of NTPL might allocate an auxilliary 5374// structure when a condvar is used or initialized. cond_destroy() would 5375// release the helper structure. Our reinitialize-after-timedwait fix 5376// put excessive stress on malloc/free and locks protecting the c-heap. 5377// 5378// We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. 5379// It may be possible to refine (4) by checking the kernel and NTPL verisons 5380// and only enabling the work-around for vulnerable environments. 5381 5382// utility to compute the abstime argument to timedwait: 5383// millis is the relative timeout time 5384// abstime will be the absolute timeout time 5385// TODO: replace compute_abstime() with unpackTime() 5386 5387static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { 5388 if (millis < 0) millis = 0; 5389 struct timeval now; 5390 int status = gettimeofday(&now, NULL); 5391 assert(status == 0, "gettimeofday"); 5392 jlong seconds = millis / 1000; 5393 millis %= 1000; 5394 if (seconds > 50000000) { // see man cond_timedwait(3T) 5395 seconds = 50000000; 5396 } 5397 abstime->tv_sec = now.tv_sec + seconds; 5398 long usec = now.tv_usec + millis * 1000; 5399 if (usec >= 1000000) { 5400 abstime->tv_sec += 1; 5401 usec -= 1000000; 5402 } 5403 abstime->tv_nsec = usec * 1000; 5404 return abstime; 5405} 5406 5407 5408// Test-and-clear _Event, always leaves _Event set to 0, returns immediately. 5409// Conceptually TryPark() should be equivalent to park(0). 5410 5411int os::PlatformEvent::TryPark() { 5412 for (;;) { 5413 const int v = _Event ; 5414 guarantee ((v == 0) || (v == 1), "invariant") ; 5415 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ; 5416 } 5417} 5418 5419void os::PlatformEvent::park() { // AKA "down()" 5420 // Invariant: Only the thread associated with the Event/PlatformEvent 5421 // may call park(). 5422 // TODO: assert that _Assoc != NULL or _Assoc == Self 5423 int v ; 5424 for (;;) { 5425 v = _Event ; 5426 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 5427 } 5428 guarantee (v >= 0, "invariant") ; 5429 if (v == 0) { 5430 // Do this the hard way by blocking ... 5431 int status = pthread_mutex_lock(_mutex); 5432 assert_status(status == 0, status, "mutex_lock"); 5433 guarantee (_nParked == 0, "invariant") ; 5434 ++ _nParked ; 5435 while (_Event < 0) { 5436 status = pthread_cond_wait(_cond, _mutex); 5437 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... 5438 // Treat this the same as if the wait was interrupted 5439 if (status == ETIMEDOUT) { status = EINTR; } 5440 assert_status(status == 0 || status == EINTR, status, "cond_wait"); 5441 } 5442 -- _nParked ; 5443 5444 // In theory we could move the ST of 0 into _Event past the unlock(), 5445 // but then we'd need a MEMBAR after the ST. 5446 _Event = 0 ; 5447 status = pthread_mutex_unlock(_mutex); 5448 assert_status(status == 0, status, "mutex_unlock"); 5449 } 5450 guarantee (_Event >= 0, "invariant") ; 5451} 5452 5453int os::PlatformEvent::park(jlong millis) { 5454 guarantee (_nParked == 0, "invariant") ; 5455 5456 int v ; 5457 for (;;) { 5458 v = _Event ; 5459 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ; 5460 } 5461 guarantee (v >= 0, "invariant") ; 5462 if (v != 0) return OS_OK ; 5463 5464 // We do this the hard way, by blocking the thread. 5465 // Consider enforcing a minimum timeout value. 5466 struct timespec abst; 5467 compute_abstime(&abst, millis); 5468 5469 int ret = OS_TIMEOUT; 5470 int status = pthread_mutex_lock(_mutex); 5471 assert_status(status == 0, status, "mutex_lock"); 5472 guarantee (_nParked == 0, "invariant") ; 5473 ++_nParked ; 5474 5475 // Object.wait(timo) will return because of 5476 // (a) notification 5477 // (b) timeout 5478 // (c) thread.interrupt 5479 // 5480 // Thread.interrupt and object.notify{All} both call Event::set. 5481 // That is, we treat thread.interrupt as a special case of notification. 5482 // The underlying Solaris implementation, cond_timedwait, admits 5483 // spurious/premature wakeups, but the JLS/JVM spec prevents the 5484 // JVM from making those visible to Java code. As such, we must 5485 // filter out spurious wakeups. We assume all ETIME returns are valid. 5486 // 5487 // TODO: properly differentiate simultaneous notify+interrupt. 5488 // In that case, we should propagate the notify to another waiter. 5489 5490 while (_Event < 0) { 5491 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); 5492 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 5493 pthread_cond_destroy (_cond); 5494 pthread_cond_init (_cond, NULL) ; 5495 } 5496 assert_status(status == 0 || status == EINTR || 5497 status == ETIMEDOUT, 5498 status, "cond_timedwait"); 5499 if (!FilterSpuriousWakeups) break ; // previous semantics 5500 if (status == ETIMEDOUT) break ; 5501 // We consume and ignore EINTR and spurious wakeups. 5502 } 5503 --_nParked ; 5504 if (_Event >= 0) { 5505 ret = OS_OK; 5506 } 5507 _Event = 0 ; 5508 status = pthread_mutex_unlock(_mutex); 5509 assert_status(status == 0, status, "mutex_unlock"); 5510 assert (_nParked == 0, "invariant") ; 5511 return ret; 5512} 5513 5514void os::PlatformEvent::unpark() { 5515 int v, AnyWaiters ; 5516 for (;;) { 5517 v = _Event ; 5518 if (v > 0) { 5519 // The LD of _Event could have reordered or be satisfied 5520 // by a read-aside from this processor's write buffer. 5521 // To avoid problems execute a barrier and then 5522 // ratify the value. 5523 OrderAccess::fence() ; 5524 if (_Event == v) return ; 5525 continue ; 5526 } 5527 if (Atomic::cmpxchg (v+1, &_Event, v) == v) break ; 5528 } 5529 if (v < 0) { 5530 // Wait for the thread associated with the event to vacate 5531 int status = pthread_mutex_lock(_mutex); 5532 assert_status(status == 0, status, "mutex_lock"); 5533 AnyWaiters = _nParked ; 5534 assert (AnyWaiters == 0 || AnyWaiters == 1, "invariant") ; 5535 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { 5536 AnyWaiters = 0 ; 5537 pthread_cond_signal (_cond); 5538 } 5539 status = pthread_mutex_unlock(_mutex); 5540 assert_status(status == 0, status, "mutex_unlock"); 5541 if (AnyWaiters != 0) { 5542 status = pthread_cond_signal(_cond); 5543 assert_status(status == 0, status, "cond_signal"); 5544 } 5545 } 5546 5547 // Note that we signal() _after dropping the lock for "immortal" Events. 5548 // This is safe and avoids a common class of futile wakeups. In rare 5549 // circumstances this can cause a thread to return prematurely from 5550 // cond_{timed}wait() but the spurious wakeup is benign and the victim will 5551 // simply re-test the condition and re-park itself. 5552} 5553 5554 5555// JSR166 5556// ------------------------------------------------------- 5557 5558/* 5559 * The solaris and bsd implementations of park/unpark are fairly 5560 * conservative for now, but can be improved. They currently use a 5561 * mutex/condvar pair, plus a a count. 5562 * Park decrements count if > 0, else does a condvar wait. Unpark 5563 * sets count to 1 and signals condvar. Only one thread ever waits 5564 * on the condvar. Contention seen when trying to park implies that someone 5565 * is unparking you, so don't wait. And spurious returns are fine, so there 5566 * is no need to track notifications. 5567 */ 5568 5569#define MAX_SECS 100000000 5570/* 5571 * This code is common to bsd and solaris and will be moved to a 5572 * common place in dolphin. 5573 * 5574 * The passed in time value is either a relative time in nanoseconds 5575 * or an absolute time in milliseconds. Either way it has to be unpacked 5576 * into suitable seconds and nanoseconds components and stored in the 5577 * given timespec structure. 5578 * Given time is a 64-bit value and the time_t used in the timespec is only 5579 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for 5580 * overflow if times way in the future are given. Further on Solaris versions 5581 * prior to 10 there is a restriction (see cond_timedwait) that the specified 5582 * number of seconds, in abstime, is less than current_time + 100,000,000. 5583 * As it will be 28 years before "now + 100000000" will overflow we can 5584 * ignore overflow and just impose a hard-limit on seconds using the value 5585 * of "now + 100,000,000". This places a limit on the timeout of about 3.17 5586 * years from "now". 5587 */ 5588 5589static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { 5590 assert (time > 0, "convertTime"); 5591 5592 struct timeval now; 5593 int status = gettimeofday(&now, NULL); 5594 assert(status == 0, "gettimeofday"); 5595 5596 time_t max_secs = now.tv_sec + MAX_SECS; 5597 5598 if (isAbsolute) { 5599 jlong secs = time / 1000; 5600 if (secs > max_secs) { 5601 absTime->tv_sec = max_secs; 5602 } 5603 else { 5604 absTime->tv_sec = secs; 5605 } 5606 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; 5607 } 5608 else { 5609 jlong secs = time / NANOSECS_PER_SEC; 5610 if (secs >= MAX_SECS) { 5611 absTime->tv_sec = max_secs; 5612 absTime->tv_nsec = 0; 5613 } 5614 else { 5615 absTime->tv_sec = now.tv_sec + secs; 5616 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; 5617 if (absTime->tv_nsec >= NANOSECS_PER_SEC) { 5618 absTime->tv_nsec -= NANOSECS_PER_SEC; 5619 ++absTime->tv_sec; // note: this must be <= max_secs 5620 } 5621 } 5622 } 5623 assert(absTime->tv_sec >= 0, "tv_sec < 0"); 5624 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); 5625 assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); 5626 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); 5627} 5628 5629void Parker::park(bool isAbsolute, jlong time) { 5630 // Optional fast-path check: 5631 // Return immediately if a permit is available. 5632 if (_counter > 0) { 5633 _counter = 0 ; 5634 OrderAccess::fence(); 5635 return ; 5636 } 5637 5638 Thread* thread = Thread::current(); 5639 assert(thread->is_Java_thread(), "Must be JavaThread"); 5640 JavaThread *jt = (JavaThread *)thread; 5641 5642 // Optional optimization -- avoid state transitions if there's an interrupt pending. 5643 // Check interrupt before trying to wait 5644 if (Thread::is_interrupted(thread, false)) { 5645 return; 5646 } 5647 5648 // Next, demultiplex/decode time arguments 5649 struct timespec absTime; 5650 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all 5651 return; 5652 } 5653 if (time > 0) { 5654 unpackTime(&absTime, isAbsolute, time); 5655 } 5656 5657 5658 // Enter safepoint region 5659 // Beware of deadlocks such as 6317397. 5660 // The per-thread Parker:: mutex is a classic leaf-lock. 5661 // In particular a thread must never block on the Threads_lock while 5662 // holding the Parker:: mutex. If safepoints are pending both the 5663 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. 5664 ThreadBlockInVM tbivm(jt); 5665 5666 // Don't wait if cannot get lock since interference arises from 5667 // unblocking. Also. check interrupt before trying wait 5668 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { 5669 return; 5670 } 5671 5672 int status ; 5673 if (_counter > 0) { // no wait needed 5674 _counter = 0; 5675 status = pthread_mutex_unlock(_mutex); 5676 assert (status == 0, "invariant") ; 5677 OrderAccess::fence(); 5678 return; 5679 } 5680 5681#ifdef ASSERT 5682 // Don't catch signals while blocked; let the running threads have the signals. 5683 // (This allows a debugger to break into the running thread.) 5684 sigset_t oldsigs; 5685 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); 5686 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); 5687#endif 5688 5689 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 5690 jt->set_suspend_equivalent(); 5691 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() 5692 5693 if (time == 0) { 5694 status = pthread_cond_wait (_cond, _mutex) ; 5695 } else { 5696 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ; 5697 if (status != 0 && WorkAroundNPTLTimedWaitHang) { 5698 pthread_cond_destroy (_cond) ; 5699 pthread_cond_init (_cond, NULL); 5700 } 5701 } 5702 assert_status(status == 0 || status == EINTR || 5703 status == ETIMEDOUT, 5704 status, "cond_timedwait"); 5705 5706#ifdef ASSERT 5707 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); 5708#endif 5709 5710 _counter = 0 ; 5711 status = pthread_mutex_unlock(_mutex) ; 5712 assert_status(status == 0, status, "invariant") ; 5713 // If externally suspended while waiting, re-suspend 5714 if (jt->handle_special_suspend_equivalent_condition()) { 5715 jt->java_suspend_self(); 5716 } 5717 5718 OrderAccess::fence(); 5719} 5720 5721void Parker::unpark() { 5722 int s, status ; 5723 status = pthread_mutex_lock(_mutex); 5724 assert (status == 0, "invariant") ; 5725 s = _counter; 5726 _counter = 1; 5727 if (s < 1) { 5728 if (WorkAroundNPTLTimedWaitHang) { 5729 status = pthread_cond_signal (_cond) ; 5730 assert (status == 0, "invariant") ; 5731 status = pthread_mutex_unlock(_mutex); 5732 assert (status == 0, "invariant") ; 5733 } else { 5734 status = pthread_mutex_unlock(_mutex); 5735 assert (status == 0, "invariant") ; 5736 status = pthread_cond_signal (_cond) ; 5737 assert (status == 0, "invariant") ; 5738 } 5739 } else { 5740 pthread_mutex_unlock(_mutex); 5741 assert (status == 0, "invariant") ; 5742 } 5743} 5744 5745 5746/* Darwin has no "environ" in a dynamic library. */ 5747#ifdef __APPLE__ 5748#include <crt_externs.h> 5749#define environ (*_NSGetEnviron()) 5750#else 5751extern char** environ; 5752#endif 5753 5754// Run the specified command in a separate process. Return its exit value, 5755// or -1 on failure (e.g. can't fork a new process). 5756// Unlike system(), this function can be called from signal handler. It 5757// doesn't block SIGINT et al. 5758int os::fork_and_exec(char* cmd) { 5759 const char * argv[4] = {"sh", "-c", cmd, NULL}; 5760 5761 // fork() in BsdThreads/NPTL is not async-safe. It needs to run 5762 // pthread_atfork handlers and reset pthread library. All we need is a 5763 // separate process to execve. Make a direct syscall to fork process. 5764 // On IA64 there's no fork syscall, we have to use fork() and hope for 5765 // the best... 5766 pid_t pid = fork(); 5767 5768 if (pid < 0) { 5769 // fork failed 5770 return -1; 5771 5772 } else if (pid == 0) { 5773 // child process 5774 5775 // execve() in BsdThreads will call pthread_kill_other_threads_np() 5776 // first to kill every thread on the thread list. Because this list is 5777 // not reset by fork() (see notes above), execve() will instead kill 5778 // every thread in the parent process. We know this is the only thread 5779 // in the new process, so make a system call directly. 5780 // IA64 should use normal execve() from glibc to match the glibc fork() 5781 // above. 5782 execve("/bin/sh", (char* const*)argv, environ); 5783 5784 // execve failed 5785 _exit(-1); 5786 5787 } else { 5788 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't 5789 // care about the actual exit code, for now. 5790 5791 int status; 5792 5793 // Wait for the child process to exit. This returns immediately if 5794 // the child has already exited. */ 5795 while (waitpid(pid, &status, 0) < 0) { 5796 switch (errno) { 5797 case ECHILD: return 0; 5798 case EINTR: break; 5799 default: return -1; 5800 } 5801 } 5802 5803 if (WIFEXITED(status)) { 5804 // The child exited normally; get its exit code. 5805 return WEXITSTATUS(status); 5806 } else if (WIFSIGNALED(status)) { 5807 // The child exited because of a signal 5808 // The best value to return is 0x80 + signal number, 5809 // because that is what all Unix shells do, and because 5810 // it allows callers to distinguish between process exit and 5811 // process death by signal. 5812 return 0x80 + WTERMSIG(status); 5813 } else { 5814 // Unknown exit code; pass it through 5815 return status; 5816 } 5817 } 5818} 5819 5820// is_headless_jre() 5821// 5822// Test for the existence of xawt/libmawt.so or libawt_xawt.so 5823// in order to report if we are running in a headless jre 5824// 5825// Since JDK8 xawt/libmawt.so was moved into the same directory 5826// as libawt.so, and renamed libawt_xawt.so 5827// 5828bool os::is_headless_jre() { 5829 struct stat statbuf; 5830 char buf[MAXPATHLEN]; 5831 char libmawtpath[MAXPATHLEN]; 5832 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; 5833 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; 5834 char *p; 5835 5836 // Get path to libjvm.so 5837 os::jvm_path(buf, sizeof(buf)); 5838 5839 // Get rid of libjvm.so 5840 p = strrchr(buf, '/'); 5841 if (p == NULL) return false; 5842 else *p = '\0'; 5843 5844 // Get rid of client or server 5845 p = strrchr(buf, '/'); 5846 if (p == NULL) return false; 5847 else *p = '\0'; 5848 5849 // check xawt/libmawt.so 5850 strcpy(libmawtpath, buf); 5851 strcat(libmawtpath, xawtstr); 5852 if (::stat(libmawtpath, &statbuf) == 0) return false; 5853 5854 // check libawt_xawt.so 5855 strcpy(libmawtpath, buf); 5856 strcat(libmawtpath, new_xawtstr); 5857 if (::stat(libmawtpath, &statbuf) == 0) return false; 5858 5859 return true; 5860} 5861