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