1 /* 2 * Copyright (c) 1999, 2016, 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 #include "utilities/globalDefinitions.hpp" 26 #include "prims/jvm.h" 27 #include "semaphore_posix.hpp" 28 #include "runtime/frame.inline.hpp" 29 #include "runtime/interfaceSupport.hpp" 30 #include "runtime/os.hpp" 31 #include "utilities/vmError.hpp" 32 33 #include <signal.h> 34 #include <unistd.h> 35 #include <sys/resource.h> 36 #include <sys/utsname.h> 37 #include <pthread.h> 38 #include <semaphore.h> 39 #include <signal.h> 40 41 // Todo: provide a os::get_max_process_id() or similar. Number of processes 42 // may have been configured, can be read more accurately from proc fs etc. 43 #ifndef MAX_PID 44 #define MAX_PID INT_MAX 45 #endif 46 #define IS_VALID_PID(p) (p > 0 && p < MAX_PID) 47 48 // Check core dump limit and report possible place where core can be found 49 void os::check_dump_limit(char* buffer, size_t bufferSize) { 50 int n; 51 struct rlimit rlim; 52 bool success; 53 54 char core_path[PATH_MAX]; 55 n = get_core_path(core_path, PATH_MAX); 56 57 if (n <= 0) { 58 jio_snprintf(buffer, bufferSize, "core.%d (may not exist)", current_process_id()); 59 success = true; 60 #ifdef LINUX 61 } else if (core_path[0] == '"') { // redirect to user process 62 jio_snprintf(buffer, bufferSize, "Core dumps may be processed with %s", core_path); 63 success = true; 64 #endif 65 } else if (getrlimit(RLIMIT_CORE, &rlim) != 0) { 66 jio_snprintf(buffer, bufferSize, "%s (may not exist)", core_path); 67 success = true; 68 } else { 69 switch(rlim.rlim_cur) { 70 case RLIM_INFINITY: 71 jio_snprintf(buffer, bufferSize, "%s", core_path); 72 success = true; 73 break; 74 case 0: 75 jio_snprintf(buffer, bufferSize, "Core dumps have been disabled. To enable core dumping, try \"ulimit -c unlimited\" before starting Java again"); 76 success = false; 77 break; 78 default: 79 jio_snprintf(buffer, bufferSize, "%s (max size %lu kB). To ensure a full core dump, try \"ulimit -c unlimited\" before starting Java again", core_path, (unsigned long)(rlim.rlim_cur >> 10)); 80 success = true; 81 break; 82 } 83 } 84 85 VMError::record_coredump_status(buffer, success); 86 } 87 88 int os::get_native_stack(address* stack, int frames, int toSkip) { 89 #ifdef _NMT_NOINLINE_ 90 toSkip++; 91 #endif 92 93 int frame_idx = 0; 94 int num_of_frames; // number of frames captured 95 frame fr = os::current_frame(); 96 while (fr.pc() && frame_idx < frames) { 97 if (toSkip > 0) { 98 toSkip --; 99 } else { 100 stack[frame_idx ++] = fr.pc(); 101 } 102 if (fr.fp() == NULL || fr.cb() != NULL || 103 fr.sender_pc() == NULL || os::is_first_C_frame(&fr)) break; 104 105 if (fr.sender_pc() && !os::is_first_C_frame(&fr)) { 106 fr = os::get_sender_for_C_frame(&fr); 107 } else { 108 break; 109 } 110 } 111 num_of_frames = frame_idx; 112 for (; frame_idx < frames; frame_idx ++) { 113 stack[frame_idx] = NULL; 114 } 115 116 return num_of_frames; 117 } 118 119 120 bool os::unsetenv(const char* name) { 121 assert(name != NULL, "Null pointer"); 122 return (::unsetenv(name) == 0); 123 } 124 125 int os::get_last_error() { 126 return errno; 127 } 128 129 bool os::is_debugger_attached() { 130 // not implemented 131 return false; 132 } 133 134 void os::wait_for_keypress_at_exit(void) { 135 // don't do anything on posix platforms 136 return; 137 } 138 139 // Multiple threads can race in this code, and can remap over each other with MAP_FIXED, 140 // so on posix, unmap the section at the start and at the end of the chunk that we mapped 141 // rather than unmapping and remapping the whole chunk to get requested alignment. 142 char* os::reserve_memory_aligned(size_t size, size_t alignment) { 143 assert((alignment & (os::vm_allocation_granularity() - 1)) == 0, 144 "Alignment must be a multiple of allocation granularity (page size)"); 145 assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned"); 146 147 size_t extra_size = size + alignment; 148 assert(extra_size >= size, "overflow, size is too large to allow alignment"); 149 150 char* extra_base = os::reserve_memory(extra_size, NULL, alignment); 151 152 if (extra_base == NULL) { 153 return NULL; 154 } 155 156 // Do manual alignment 157 char* aligned_base = (char*) align_size_up((uintptr_t) extra_base, alignment); 158 159 // [ | | ] 160 // ^ extra_base 161 // ^ extra_base + begin_offset == aligned_base 162 // extra_base + begin_offset + size ^ 163 // extra_base + extra_size ^ 164 // |<>| == begin_offset 165 // end_offset == |<>| 166 size_t begin_offset = aligned_base - extra_base; 167 size_t end_offset = (extra_base + extra_size) - (aligned_base + size); 168 169 if (begin_offset > 0) { 170 os::release_memory(extra_base, begin_offset); 171 } 172 173 if (end_offset > 0) { 174 os::release_memory(extra_base + begin_offset + size, end_offset); 175 } 176 177 return aligned_base; 178 } 179 180 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) { 181 return vsnprintf(buf, len, fmt, args); 182 } 183 184 void os::Posix::print_load_average(outputStream* st) { 185 st->print("load average:"); 186 double loadavg[3]; 187 os::loadavg(loadavg, 3); 188 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]); 189 st->cr(); 190 } 191 192 void os::Posix::print_rlimit_info(outputStream* st) { 193 st->print("rlimit:"); 194 struct rlimit rlim; 195 196 st->print(" STACK "); 197 getrlimit(RLIMIT_STACK, &rlim); 198 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 199 else st->print("%luk", rlim.rlim_cur >> 10); 200 201 st->print(", CORE "); 202 getrlimit(RLIMIT_CORE, &rlim); 203 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 204 else st->print("%luk", rlim.rlim_cur >> 10); 205 206 // Isn't there on solaris 207 #if !defined(TARGET_OS_FAMILY_solaris) && !defined(TARGET_OS_FAMILY_aix) 208 st->print(", NPROC "); 209 getrlimit(RLIMIT_NPROC, &rlim); 210 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 211 else st->print("%lu", rlim.rlim_cur); 212 #endif 213 214 st->print(", NOFILE "); 215 getrlimit(RLIMIT_NOFILE, &rlim); 216 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 217 else st->print("%lu", rlim.rlim_cur); 218 219 st->print(", AS "); 220 getrlimit(RLIMIT_AS, &rlim); 221 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 222 else st->print("%luk", rlim.rlim_cur >> 10); 223 st->cr(); 224 } 225 226 void os::Posix::print_uname_info(outputStream* st) { 227 // kernel 228 st->print("uname:"); 229 struct utsname name; 230 uname(&name); 231 st->print("%s ", name.sysname); 232 #ifdef ASSERT 233 st->print("%s ", name.nodename); 234 #endif 235 st->print("%s ", name.release); 236 st->print("%s ", name.version); 237 st->print("%s", name.machine); 238 st->cr(); 239 } 240 241 bool os::get_host_name(char* buf, size_t buflen) { 242 struct utsname name; 243 uname(&name); 244 jio_snprintf(buf, buflen, "%s", name.nodename); 245 return true; 246 } 247 248 bool os::has_allocatable_memory_limit(julong* limit) { 249 struct rlimit rlim; 250 int getrlimit_res = getrlimit(RLIMIT_AS, &rlim); 251 // if there was an error when calling getrlimit, assume that there is no limitation 252 // on virtual memory. 253 bool result; 254 if ((getrlimit_res != 0) || (rlim.rlim_cur == RLIM_INFINITY)) { 255 result = false; 256 } else { 257 *limit = (julong)rlim.rlim_cur; 258 result = true; 259 } 260 #ifdef _LP64 261 return result; 262 #else 263 // arbitrary virtual space limit for 32 bit Unices found by testing. If 264 // getrlimit above returned a limit, bound it with this limit. Otherwise 265 // directly use it. 266 const julong max_virtual_limit = (julong)3800*M; 267 if (result) { 268 *limit = MIN2(*limit, max_virtual_limit); 269 } else { 270 *limit = max_virtual_limit; 271 } 272 273 // bound by actually allocatable memory. The algorithm uses two bounds, an 274 // upper and a lower limit. The upper limit is the current highest amount of 275 // memory that could not be allocated, the lower limit is the current highest 276 // amount of memory that could be allocated. 277 // The algorithm iteratively refines the result by halving the difference 278 // between these limits, updating either the upper limit (if that value could 279 // not be allocated) or the lower limit (if the that value could be allocated) 280 // until the difference between these limits is "small". 281 282 // the minimum amount of memory we care about allocating. 283 const julong min_allocation_size = M; 284 285 julong upper_limit = *limit; 286 287 // first check a few trivial cases 288 if (is_allocatable(upper_limit) || (upper_limit <= min_allocation_size)) { 289 *limit = upper_limit; 290 } else if (!is_allocatable(min_allocation_size)) { 291 // we found that not even min_allocation_size is allocatable. Return it 292 // anyway. There is no point to search for a better value any more. 293 *limit = min_allocation_size; 294 } else { 295 // perform the binary search. 296 julong lower_limit = min_allocation_size; 297 while ((upper_limit - lower_limit) > min_allocation_size) { 298 julong temp_limit = ((upper_limit - lower_limit) / 2) + lower_limit; 299 temp_limit = align_size_down_(temp_limit, min_allocation_size); 300 if (is_allocatable(temp_limit)) { 301 lower_limit = temp_limit; 302 } else { 303 upper_limit = temp_limit; 304 } 305 } 306 *limit = lower_limit; 307 } 308 return true; 309 #endif 310 } 311 312 const char* os::get_current_directory(char *buf, size_t buflen) { 313 return getcwd(buf, buflen); 314 } 315 316 FILE* os::open(int fd, const char* mode) { 317 return ::fdopen(fd, mode); 318 } 319 320 void os::flockfile(FILE* fp) { 321 ::flockfile(fp); 322 } 323 324 void os::funlockfile(FILE* fp) { 325 ::funlockfile(fp); 326 } 327 328 // Builds a platform dependent Agent_OnLoad_<lib_name> function name 329 // which is used to find statically linked in agents. 330 // Parameters: 331 // sym_name: Symbol in library we are looking for 332 // lib_name: Name of library to look in, NULL for shared libs. 333 // is_absolute_path == true if lib_name is absolute path to agent 334 // such as "/a/b/libL.so" 335 // == false if only the base name of the library is passed in 336 // such as "L" 337 char* os::build_agent_function_name(const char *sym_name, const char *lib_name, 338 bool is_absolute_path) { 339 char *agent_entry_name; 340 size_t len; 341 size_t name_len; 342 size_t prefix_len = strlen(JNI_LIB_PREFIX); 343 size_t suffix_len = strlen(JNI_LIB_SUFFIX); 344 const char *start; 345 346 if (lib_name != NULL) { 347 name_len = strlen(lib_name); 348 if (is_absolute_path) { 349 // Need to strip path, prefix and suffix 350 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) { 351 lib_name = ++start; 352 } 353 if (strlen(lib_name) <= (prefix_len + suffix_len)) { 354 return NULL; 355 } 356 lib_name += prefix_len; 357 name_len = strlen(lib_name) - suffix_len; 358 } 359 } 360 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2; 361 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread); 362 if (agent_entry_name == NULL) { 363 return NULL; 364 } 365 strcpy(agent_entry_name, sym_name); 366 if (lib_name != NULL) { 367 strcat(agent_entry_name, "_"); 368 strncat(agent_entry_name, lib_name, name_len); 369 } 370 return agent_entry_name; 371 } 372 373 int os::sleep(Thread* thread, jlong millis, bool interruptible) { 374 assert(thread == Thread::current(), "thread consistency check"); 375 376 ParkEvent * const slp = thread->_SleepEvent ; 377 slp->reset() ; 378 OrderAccess::fence() ; 379 380 if (interruptible) { 381 jlong prevtime = javaTimeNanos(); 382 383 for (;;) { 384 if (os::is_interrupted(thread, true)) { 385 return OS_INTRPT; 386 } 387 388 jlong newtime = javaTimeNanos(); 389 390 if (newtime - prevtime < 0) { 391 // time moving backwards, should only happen if no monotonic clock 392 // not a guarantee() because JVM should not abort on kernel/glibc bugs 393 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected in os::sleep(interruptible)"); 394 } else { 395 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 396 } 397 398 if (millis <= 0) { 399 return OS_OK; 400 } 401 402 prevtime = newtime; 403 404 { 405 assert(thread->is_Java_thread(), "sanity check"); 406 JavaThread *jt = (JavaThread *) thread; 407 ThreadBlockInVM tbivm(jt); 408 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 409 410 jt->set_suspend_equivalent(); 411 // cleared by handle_special_suspend_equivalent_condition() or 412 // java_suspend_self() via check_and_wait_while_suspended() 413 414 slp->park(millis); 415 416 // were we externally suspended while we were waiting? 417 jt->check_and_wait_while_suspended(); 418 } 419 } 420 } else { 421 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 422 jlong prevtime = javaTimeNanos(); 423 424 for (;;) { 425 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 426 // the 1st iteration ... 427 jlong newtime = javaTimeNanos(); 428 429 if (newtime - prevtime < 0) { 430 // time moving backwards, should only happen if no monotonic clock 431 // not a guarantee() because JVM should not abort on kernel/glibc bugs 432 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected on os::sleep(!interruptible)"); 433 } else { 434 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 435 } 436 437 if (millis <= 0) break ; 438 439 prevtime = newtime; 440 slp->park(millis); 441 } 442 return OS_OK ; 443 } 444 } 445 446 //////////////////////////////////////////////////////////////////////////////// 447 // interrupt support 448 449 void os::interrupt(Thread* thread) { 450 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 451 "possibility of dangling Thread pointer"); 452 453 OSThread* osthread = thread->osthread(); 454 455 if (!osthread->interrupted()) { 456 osthread->set_interrupted(true); 457 // More than one thread can get here with the same value of osthread, 458 // resulting in multiple notifications. We do, however, want the store 459 // to interrupted() to be visible to other threads before we execute unpark(). 460 OrderAccess::fence(); 461 ParkEvent * const slp = thread->_SleepEvent ; 462 if (slp != NULL) slp->unpark() ; 463 } 464 465 // For JSR166. Unpark even if interrupt status already was set 466 if (thread->is_Java_thread()) 467 ((JavaThread*)thread)->parker()->unpark(); 468 469 ParkEvent * ev = thread->_ParkEvent ; 470 if (ev != NULL) ev->unpark() ; 471 472 } 473 474 bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 475 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 476 "possibility of dangling Thread pointer"); 477 478 OSThread* osthread = thread->osthread(); 479 480 bool interrupted = osthread->interrupted(); 481 482 // NOTE that since there is no "lock" around the interrupt and 483 // is_interrupted operations, there is the possibility that the 484 // interrupted flag (in osThread) will be "false" but that the 485 // low-level events will be in the signaled state. This is 486 // intentional. The effect of this is that Object.wait() and 487 // LockSupport.park() will appear to have a spurious wakeup, which 488 // is allowed and not harmful, and the possibility is so rare that 489 // it is not worth the added complexity to add yet another lock. 490 // For the sleep event an explicit reset is performed on entry 491 // to os::sleep, so there is no early return. It has also been 492 // recommended not to put the interrupted flag into the "event" 493 // structure because it hides the issue. 494 if (interrupted && clear_interrupted) { 495 osthread->set_interrupted(false); 496 // consider thread->_SleepEvent->reset() ... optional optimization 497 } 498 499 return interrupted; 500 } 501 502 503 504 static const struct { 505 int sig; const char* name; 506 } 507 g_signal_info[] = 508 { 509 { SIGABRT, "SIGABRT" }, 510 #ifdef SIGAIO 511 { SIGAIO, "SIGAIO" }, 512 #endif 513 { SIGALRM, "SIGALRM" }, 514 #ifdef SIGALRM1 515 { SIGALRM1, "SIGALRM1" }, 516 #endif 517 { SIGBUS, "SIGBUS" }, 518 #ifdef SIGCANCEL 519 { SIGCANCEL, "SIGCANCEL" }, 520 #endif 521 { SIGCHLD, "SIGCHLD" }, 522 #ifdef SIGCLD 523 { SIGCLD, "SIGCLD" }, 524 #endif 525 { SIGCONT, "SIGCONT" }, 526 #ifdef SIGCPUFAIL 527 { SIGCPUFAIL, "SIGCPUFAIL" }, 528 #endif 529 #ifdef SIGDANGER 530 { SIGDANGER, "SIGDANGER" }, 531 #endif 532 #ifdef SIGDIL 533 { SIGDIL, "SIGDIL" }, 534 #endif 535 #ifdef SIGEMT 536 { SIGEMT, "SIGEMT" }, 537 #endif 538 { SIGFPE, "SIGFPE" }, 539 #ifdef SIGFREEZE 540 { SIGFREEZE, "SIGFREEZE" }, 541 #endif 542 #ifdef SIGGFAULT 543 { SIGGFAULT, "SIGGFAULT" }, 544 #endif 545 #ifdef SIGGRANT 546 { SIGGRANT, "SIGGRANT" }, 547 #endif 548 { SIGHUP, "SIGHUP" }, 549 { SIGILL, "SIGILL" }, 550 { SIGINT, "SIGINT" }, 551 #ifdef SIGIO 552 { SIGIO, "SIGIO" }, 553 #endif 554 #ifdef SIGIOINT 555 { SIGIOINT, "SIGIOINT" }, 556 #endif 557 #ifdef SIGIOT 558 // SIGIOT is there for BSD compatibility, but on most Unices just a 559 // synonym for SIGABRT. The result should be "SIGABRT", not 560 // "SIGIOT". 561 #if (SIGIOT != SIGABRT ) 562 { SIGIOT, "SIGIOT" }, 563 #endif 564 #endif 565 #ifdef SIGKAP 566 { SIGKAP, "SIGKAP" }, 567 #endif 568 { SIGKILL, "SIGKILL" }, 569 #ifdef SIGLOST 570 { SIGLOST, "SIGLOST" }, 571 #endif 572 #ifdef SIGLWP 573 { SIGLWP, "SIGLWP" }, 574 #endif 575 #ifdef SIGLWPTIMER 576 { SIGLWPTIMER, "SIGLWPTIMER" }, 577 #endif 578 #ifdef SIGMIGRATE 579 { SIGMIGRATE, "SIGMIGRATE" }, 580 #endif 581 #ifdef SIGMSG 582 { SIGMSG, "SIGMSG" }, 583 #endif 584 { SIGPIPE, "SIGPIPE" }, 585 #ifdef SIGPOLL 586 { SIGPOLL, "SIGPOLL" }, 587 #endif 588 #ifdef SIGPRE 589 { SIGPRE, "SIGPRE" }, 590 #endif 591 { SIGPROF, "SIGPROF" }, 592 #ifdef SIGPTY 593 { SIGPTY, "SIGPTY" }, 594 #endif 595 #ifdef SIGPWR 596 { SIGPWR, "SIGPWR" }, 597 #endif 598 { SIGQUIT, "SIGQUIT" }, 599 #ifdef SIGRECONFIG 600 { SIGRECONFIG, "SIGRECONFIG" }, 601 #endif 602 #ifdef SIGRECOVERY 603 { SIGRECOVERY, "SIGRECOVERY" }, 604 #endif 605 #ifdef SIGRESERVE 606 { SIGRESERVE, "SIGRESERVE" }, 607 #endif 608 #ifdef SIGRETRACT 609 { SIGRETRACT, "SIGRETRACT" }, 610 #endif 611 #ifdef SIGSAK 612 { SIGSAK, "SIGSAK" }, 613 #endif 614 { SIGSEGV, "SIGSEGV" }, 615 #ifdef SIGSOUND 616 { SIGSOUND, "SIGSOUND" }, 617 #endif 618 #ifdef SIGSTKFLT 619 { SIGSTKFLT, "SIGSTKFLT" }, 620 #endif 621 { SIGSTOP, "SIGSTOP" }, 622 { SIGSYS, "SIGSYS" }, 623 #ifdef SIGSYSERROR 624 { SIGSYSERROR, "SIGSYSERROR" }, 625 #endif 626 #ifdef SIGTALRM 627 { SIGTALRM, "SIGTALRM" }, 628 #endif 629 { SIGTERM, "SIGTERM" }, 630 #ifdef SIGTHAW 631 { SIGTHAW, "SIGTHAW" }, 632 #endif 633 { SIGTRAP, "SIGTRAP" }, 634 #ifdef SIGTSTP 635 { SIGTSTP, "SIGTSTP" }, 636 #endif 637 { SIGTTIN, "SIGTTIN" }, 638 { SIGTTOU, "SIGTTOU" }, 639 #ifdef SIGURG 640 { SIGURG, "SIGURG" }, 641 #endif 642 { SIGUSR1, "SIGUSR1" }, 643 { SIGUSR2, "SIGUSR2" }, 644 #ifdef SIGVIRT 645 { SIGVIRT, "SIGVIRT" }, 646 #endif 647 { SIGVTALRM, "SIGVTALRM" }, 648 #ifdef SIGWAITING 649 { SIGWAITING, "SIGWAITING" }, 650 #endif 651 #ifdef SIGWINCH 652 { SIGWINCH, "SIGWINCH" }, 653 #endif 654 #ifdef SIGWINDOW 655 { SIGWINDOW, "SIGWINDOW" }, 656 #endif 657 { SIGXCPU, "SIGXCPU" }, 658 { SIGXFSZ, "SIGXFSZ" }, 659 #ifdef SIGXRES 660 { SIGXRES, "SIGXRES" }, 661 #endif 662 { -1, NULL } 663 }; 664 665 // Returned string is a constant. For unknown signals "UNKNOWN" is returned. 666 const char* os::Posix::get_signal_name(int sig, char* out, size_t outlen) { 667 668 const char* ret = NULL; 669 670 #ifdef SIGRTMIN 671 if (sig >= SIGRTMIN && sig <= SIGRTMAX) { 672 if (sig == SIGRTMIN) { 673 ret = "SIGRTMIN"; 674 } else if (sig == SIGRTMAX) { 675 ret = "SIGRTMAX"; 676 } else { 677 jio_snprintf(out, outlen, "SIGRTMIN+%d", sig - SIGRTMIN); 678 return out; 679 } 680 } 681 #endif 682 683 if (sig > 0) { 684 for (int idx = 0; g_signal_info[idx].sig != -1; idx ++) { 685 if (g_signal_info[idx].sig == sig) { 686 ret = g_signal_info[idx].name; 687 break; 688 } 689 } 690 } 691 692 if (!ret) { 693 if (!is_valid_signal(sig)) { 694 ret = "INVALID"; 695 } else { 696 ret = "UNKNOWN"; 697 } 698 } 699 700 if (out && outlen > 0) { 701 strncpy(out, ret, outlen); 702 out[outlen - 1] = '\0'; 703 } 704 return out; 705 } 706 707 int os::Posix::get_signal_number(const char* signal_name) { 708 char tmp[30]; 709 const char* s = signal_name; 710 if (s[0] != 'S' || s[1] != 'I' || s[2] != 'G') { 711 jio_snprintf(tmp, sizeof(tmp), "SIG%s", signal_name); 712 s = tmp; 713 } 714 for (int idx = 0; g_signal_info[idx].sig != -1; idx ++) { 715 if (strcmp(g_signal_info[idx].name, s) == 0) { 716 return g_signal_info[idx].sig; 717 } 718 } 719 return -1; 720 } 721 722 int os::get_signal_number(const char* signal_name) { 723 return os::Posix::get_signal_number(signal_name); 724 } 725 726 // Returns true if signal number is valid. 727 bool os::Posix::is_valid_signal(int sig) { 728 // MacOS not really POSIX compliant: sigaddset does not return 729 // an error for invalid signal numbers. However, MacOS does not 730 // support real time signals and simply seems to have just 33 731 // signals with no holes in the signal range. 732 #ifdef __APPLE__ 733 return sig >= 1 && sig < NSIG; 734 #else 735 // Use sigaddset to check for signal validity. 736 sigset_t set; 737 if (sigaddset(&set, sig) == -1 && errno == EINVAL) { 738 return false; 739 } 740 return true; 741 #endif 742 } 743 744 // Returns: 745 // NULL for an invalid signal number 746 // "SIG<num>" for a valid but unknown signal number 747 // signal name otherwise. 748 const char* os::exception_name(int sig, char* buf, size_t size) { 749 if (!os::Posix::is_valid_signal(sig)) { 750 return NULL; 751 } 752 const char* const name = os::Posix::get_signal_name(sig, buf, size); 753 if (strcmp(name, "UNKNOWN") == 0) { 754 jio_snprintf(buf, size, "SIG%d", sig); 755 } 756 return buf; 757 } 758 759 #define NUM_IMPORTANT_SIGS 32 760 // Returns one-line short description of a signal set in a user provided buffer. 761 const char* os::Posix::describe_signal_set_short(const sigset_t* set, char* buffer, size_t buf_size) { 762 assert(buf_size == (NUM_IMPORTANT_SIGS + 1), "wrong buffer size"); 763 // Note: for shortness, just print out the first 32. That should 764 // cover most of the useful ones, apart from realtime signals. 765 for (int sig = 1; sig <= NUM_IMPORTANT_SIGS; sig++) { 766 const int rc = sigismember(set, sig); 767 if (rc == -1 && errno == EINVAL) { 768 buffer[sig-1] = '?'; 769 } else { 770 buffer[sig-1] = rc == 0 ? '0' : '1'; 771 } 772 } 773 buffer[NUM_IMPORTANT_SIGS] = 0; 774 return buffer; 775 } 776 777 // Prints one-line description of a signal set. 778 void os::Posix::print_signal_set_short(outputStream* st, const sigset_t* set) { 779 char buf[NUM_IMPORTANT_SIGS + 1]; 780 os::Posix::describe_signal_set_short(set, buf, sizeof(buf)); 781 st->print("%s", buf); 782 } 783 784 // Writes one-line description of a combination of sigaction.sa_flags into a user 785 // provided buffer. Returns that buffer. 786 const char* os::Posix::describe_sa_flags(int flags, char* buffer, size_t size) { 787 char* p = buffer; 788 size_t remaining = size; 789 bool first = true; 790 int idx = 0; 791 792 assert(buffer, "invalid argument"); 793 794 if (size == 0) { 795 return buffer; 796 } 797 798 strncpy(buffer, "none", size); 799 800 const struct { 801 // NB: i is an unsigned int here because SA_RESETHAND is on some 802 // systems 0x80000000, which is implicitly unsigned. Assignining 803 // it to an int field would be an overflow in unsigned-to-signed 804 // conversion. 805 unsigned int i; 806 const char* s; 807 } flaginfo [] = { 808 { SA_NOCLDSTOP, "SA_NOCLDSTOP" }, 809 { SA_ONSTACK, "SA_ONSTACK" }, 810 { SA_RESETHAND, "SA_RESETHAND" }, 811 { SA_RESTART, "SA_RESTART" }, 812 { SA_SIGINFO, "SA_SIGINFO" }, 813 { SA_NOCLDWAIT, "SA_NOCLDWAIT" }, 814 { SA_NODEFER, "SA_NODEFER" }, 815 #ifdef AIX 816 { SA_ONSTACK, "SA_ONSTACK" }, 817 { SA_OLDSTYLE, "SA_OLDSTYLE" }, 818 #endif 819 { 0, NULL } 820 }; 821 822 for (idx = 0; flaginfo[idx].s && remaining > 1; idx++) { 823 if (flags & flaginfo[idx].i) { 824 if (first) { 825 jio_snprintf(p, remaining, "%s", flaginfo[idx].s); 826 first = false; 827 } else { 828 jio_snprintf(p, remaining, "|%s", flaginfo[idx].s); 829 } 830 const size_t len = strlen(p); 831 p += len; 832 remaining -= len; 833 } 834 } 835 836 buffer[size - 1] = '\0'; 837 838 return buffer; 839 } 840 841 // Prints one-line description of a combination of sigaction.sa_flags. 842 void os::Posix::print_sa_flags(outputStream* st, int flags) { 843 char buffer[0x100]; 844 os::Posix::describe_sa_flags(flags, buffer, sizeof(buffer)); 845 st->print("%s", buffer); 846 } 847 848 // Helper function for os::Posix::print_siginfo_...(): 849 // return a textual description for signal code. 850 struct enum_sigcode_desc_t { 851 const char* s_name; 852 const char* s_desc; 853 }; 854 855 static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t* out) { 856 857 const struct { 858 int sig; int code; const char* s_code; const char* s_desc; 859 } t1 [] = { 860 { SIGILL, ILL_ILLOPC, "ILL_ILLOPC", "Illegal opcode." }, 861 { SIGILL, ILL_ILLOPN, "ILL_ILLOPN", "Illegal operand." }, 862 { SIGILL, ILL_ILLADR, "ILL_ILLADR", "Illegal addressing mode." }, 863 { SIGILL, ILL_ILLTRP, "ILL_ILLTRP", "Illegal trap." }, 864 { SIGILL, ILL_PRVOPC, "ILL_PRVOPC", "Privileged opcode." }, 865 { SIGILL, ILL_PRVREG, "ILL_PRVREG", "Privileged register." }, 866 { SIGILL, ILL_COPROC, "ILL_COPROC", "Coprocessor error." }, 867 { SIGILL, ILL_BADSTK, "ILL_BADSTK", "Internal stack error." }, 868 #if defined(IA64) && defined(LINUX) 869 { SIGILL, ILL_BADIADDR, "ILL_BADIADDR", "Unimplemented instruction address" }, 870 { SIGILL, ILL_BREAK, "ILL_BREAK", "Application Break instruction" }, 871 #endif 872 { SIGFPE, FPE_INTDIV, "FPE_INTDIV", "Integer divide by zero." }, 873 { SIGFPE, FPE_INTOVF, "FPE_INTOVF", "Integer overflow." }, 874 { SIGFPE, FPE_FLTDIV, "FPE_FLTDIV", "Floating-point divide by zero." }, 875 { SIGFPE, FPE_FLTOVF, "FPE_FLTOVF", "Floating-point overflow." }, 876 { SIGFPE, FPE_FLTUND, "FPE_FLTUND", "Floating-point underflow." }, 877 { SIGFPE, FPE_FLTRES, "FPE_FLTRES", "Floating-point inexact result." }, 878 { SIGFPE, FPE_FLTINV, "FPE_FLTINV", "Invalid floating-point operation." }, 879 { SIGFPE, FPE_FLTSUB, "FPE_FLTSUB", "Subscript out of range." }, 880 { SIGSEGV, SEGV_MAPERR, "SEGV_MAPERR", "Address not mapped to object." }, 881 { SIGSEGV, SEGV_ACCERR, "SEGV_ACCERR", "Invalid permissions for mapped object." }, 882 #ifdef AIX 883 // no explanation found what keyerr would be 884 { SIGSEGV, SEGV_KEYERR, "SEGV_KEYERR", "key error" }, 885 #endif 886 #if defined(IA64) && !defined(AIX) 887 { SIGSEGV, SEGV_PSTKOVF, "SEGV_PSTKOVF", "Paragraph stack overflow" }, 888 #endif 889 #if defined(__sparc) && defined(SOLARIS) 890 // define Solaris Sparc M7 ADI SEGV signals 891 #if !defined(SEGV_ACCADI) 892 #define SEGV_ACCADI 3 893 #endif 894 { SIGSEGV, SEGV_ACCADI, "SEGV_ACCADI", "ADI not enabled for mapped object." }, 895 #if !defined(SEGV_ACCDERR) 896 #define SEGV_ACCDERR 4 897 #endif 898 { SIGSEGV, SEGV_ACCDERR, "SEGV_ACCDERR", "ADI disrupting exception." }, 899 #if !defined(SEGV_ACCPERR) 900 #define SEGV_ACCPERR 5 901 #endif 902 { SIGSEGV, SEGV_ACCPERR, "SEGV_ACCPERR", "ADI precise exception." }, 903 #endif // defined(__sparc) && defined(SOLARIS) 904 { SIGBUS, BUS_ADRALN, "BUS_ADRALN", "Invalid address alignment." }, 905 { SIGBUS, BUS_ADRERR, "BUS_ADRERR", "Nonexistent physical address." }, 906 { SIGBUS, BUS_OBJERR, "BUS_OBJERR", "Object-specific hardware error." }, 907 { SIGTRAP, TRAP_BRKPT, "TRAP_BRKPT", "Process breakpoint." }, 908 { SIGTRAP, TRAP_TRACE, "TRAP_TRACE", "Process trace trap." }, 909 { SIGCHLD, CLD_EXITED, "CLD_EXITED", "Child has exited." }, 910 { SIGCHLD, CLD_KILLED, "CLD_KILLED", "Child has terminated abnormally and did not create a core file." }, 911 { SIGCHLD, CLD_DUMPED, "CLD_DUMPED", "Child has terminated abnormally and created a core file." }, 912 { SIGCHLD, CLD_TRAPPED, "CLD_TRAPPED", "Traced child has trapped." }, 913 { SIGCHLD, CLD_STOPPED, "CLD_STOPPED", "Child has stopped." }, 914 { SIGCHLD, CLD_CONTINUED,"CLD_CONTINUED","Stopped child has continued." }, 915 #ifdef SIGPOLL 916 { SIGPOLL, POLL_OUT, "POLL_OUT", "Output buffers available." }, 917 { SIGPOLL, POLL_MSG, "POLL_MSG", "Input message available." }, 918 { SIGPOLL, POLL_ERR, "POLL_ERR", "I/O error." }, 919 { SIGPOLL, POLL_PRI, "POLL_PRI", "High priority input available." }, 920 { SIGPOLL, POLL_HUP, "POLL_HUP", "Device disconnected. [Option End]" }, 921 #endif 922 { -1, -1, NULL, NULL } 923 }; 924 925 // Codes valid in any signal context. 926 const struct { 927 int code; const char* s_code; const char* s_desc; 928 } t2 [] = { 929 { SI_USER, "SI_USER", "Signal sent by kill()." }, 930 { SI_QUEUE, "SI_QUEUE", "Signal sent by the sigqueue()." }, 931 { SI_TIMER, "SI_TIMER", "Signal generated by expiration of a timer set by timer_settime()." }, 932 { SI_ASYNCIO, "SI_ASYNCIO", "Signal generated by completion of an asynchronous I/O request." }, 933 { SI_MESGQ, "SI_MESGQ", "Signal generated by arrival of a message on an empty message queue." }, 934 // Linux specific 935 #ifdef SI_TKILL 936 { SI_TKILL, "SI_TKILL", "Signal sent by tkill (pthread_kill)" }, 937 #endif 938 #ifdef SI_DETHREAD 939 { SI_DETHREAD, "SI_DETHREAD", "Signal sent by execve() killing subsidiary threads" }, 940 #endif 941 #ifdef SI_KERNEL 942 { SI_KERNEL, "SI_KERNEL", "Signal sent by kernel." }, 943 #endif 944 #ifdef SI_SIGIO 945 { SI_SIGIO, "SI_SIGIO", "Signal sent by queued SIGIO" }, 946 #endif 947 948 #ifdef AIX 949 { SI_UNDEFINED, "SI_UNDEFINED","siginfo contains partial information" }, 950 { SI_EMPTY, "SI_EMPTY", "siginfo contains no useful information" }, 951 #endif 952 953 #ifdef __sun 954 { SI_NOINFO, "SI_NOINFO", "No signal information" }, 955 { SI_RCTL, "SI_RCTL", "kernel generated signal via rctl action" }, 956 { SI_LWP, "SI_LWP", "Signal sent via lwp_kill" }, 957 #endif 958 959 { -1, NULL, NULL } 960 }; 961 962 const char* s_code = NULL; 963 const char* s_desc = NULL; 964 965 for (int i = 0; t1[i].sig != -1; i ++) { 966 if (t1[i].sig == si->si_signo && t1[i].code == si->si_code) { 967 s_code = t1[i].s_code; 968 s_desc = t1[i].s_desc; 969 break; 970 } 971 } 972 973 if (s_code == NULL) { 974 for (int i = 0; t2[i].s_code != NULL; i ++) { 975 if (t2[i].code == si->si_code) { 976 s_code = t2[i].s_code; 977 s_desc = t2[i].s_desc; 978 } 979 } 980 } 981 982 if (s_code == NULL) { 983 out->s_name = "unknown"; 984 out->s_desc = "unknown"; 985 return false; 986 } 987 988 out->s_name = s_code; 989 out->s_desc = s_desc; 990 991 return true; 992 } 993 994 void os::print_siginfo(outputStream* os, const void* si0) { 995 996 const siginfo_t* const si = (const siginfo_t*) si0; 997 998 char buf[20]; 999 os->print("siginfo:"); 1000 1001 if (!si) { 1002 os->print(" <null>"); 1003 return; 1004 } 1005 1006 const int sig = si->si_signo; 1007 1008 os->print(" si_signo: %d (%s)", sig, os::Posix::get_signal_name(sig, buf, sizeof(buf))); 1009 1010 enum_sigcode_desc_t ed; 1011 get_signal_code_description(si, &ed); 1012 os->print(", si_code: %d (%s)", si->si_code, ed.s_name); 1013 1014 if (si->si_errno) { 1015 os->print(", si_errno: %d", si->si_errno); 1016 } 1017 1018 // Output additional information depending on the signal code. 1019 1020 // Note: Many implementations lump si_addr, si_pid, si_uid etc. together as unions, 1021 // so it depends on the context which member to use. For synchronous error signals, 1022 // we print si_addr, unless the signal was sent by another process or thread, in 1023 // which case we print out pid or tid of the sender. 1024 if (si->si_code == SI_USER || si->si_code == SI_QUEUE) { 1025 const pid_t pid = si->si_pid; 1026 os->print(", si_pid: %ld", (long) pid); 1027 if (IS_VALID_PID(pid)) { 1028 const pid_t me = getpid(); 1029 if (me == pid) { 1030 os->print(" (current process)"); 1031 } 1032 } else { 1033 os->print(" (invalid)"); 1034 } 1035 os->print(", si_uid: %ld", (long) si->si_uid); 1036 if (sig == SIGCHLD) { 1037 os->print(", si_status: %d", si->si_status); 1038 } 1039 } else if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || 1040 sig == SIGTRAP || sig == SIGFPE) { 1041 os->print(", si_addr: " PTR_FORMAT, p2i(si->si_addr)); 1042 #ifdef SIGPOLL 1043 } else if (sig == SIGPOLL) { 1044 os->print(", si_band: %ld", si->si_band); 1045 #endif 1046 } 1047 1048 } 1049 1050 int os::Posix::unblock_thread_signal_mask(const sigset_t *set) { 1051 return pthread_sigmask(SIG_UNBLOCK, set, NULL); 1052 } 1053 1054 address os::Posix::ucontext_get_pc(const ucontext_t* ctx) { 1055 #ifdef TARGET_OS_FAMILY_linux 1056 return Linux::ucontext_get_pc(ctx); 1057 #elif defined(TARGET_OS_FAMILY_solaris) 1058 return Solaris::ucontext_get_pc(ctx); 1059 #elif defined(TARGET_OS_FAMILY_aix) 1060 return Aix::ucontext_get_pc(ctx); 1061 #elif defined(TARGET_OS_FAMILY_bsd) 1062 return Bsd::ucontext_get_pc(ctx); 1063 #else 1064 VMError::report_and_die("unimplemented ucontext_get_pc"); 1065 #endif 1066 } 1067 1068 void os::Posix::ucontext_set_pc(ucontext_t* ctx, address pc) { 1069 #ifdef TARGET_OS_FAMILY_linux 1070 Linux::ucontext_set_pc(ctx, pc); 1071 #elif defined(TARGET_OS_FAMILY_solaris) 1072 Solaris::ucontext_set_pc(ctx, pc); 1073 #elif defined(TARGET_OS_FAMILY_aix) 1074 Aix::ucontext_set_pc(ctx, pc); 1075 #elif defined(TARGET_OS_FAMILY_bsd) 1076 Bsd::ucontext_set_pc(ctx, pc); 1077 #else 1078 VMError::report_and_die("unimplemented ucontext_get_pc"); 1079 #endif 1080 } 1081 1082 char* os::Posix::describe_pthread_attr(char* buf, size_t buflen, const pthread_attr_t* attr) { 1083 size_t stack_size = 0; 1084 size_t guard_size = 0; 1085 int detachstate = 0; 1086 pthread_attr_getstacksize(attr, &stack_size); 1087 pthread_attr_getguardsize(attr, &guard_size); 1088 pthread_attr_getdetachstate(attr, &detachstate); 1089 jio_snprintf(buf, buflen, "stacksize: " SIZE_FORMAT "k, guardsize: " SIZE_FORMAT "k, %s", 1090 stack_size / 1024, guard_size / 1024, 1091 (detachstate == PTHREAD_CREATE_DETACHED ? "detached" : "joinable")); 1092 return buf; 1093 } 1094 1095 1096 os::WatcherThreadCrashProtection::WatcherThreadCrashProtection() { 1097 assert(Thread::current()->is_Watcher_thread(), "Must be WatcherThread"); 1098 } 1099 1100 /* 1101 * See the caveats for this class in os_posix.hpp 1102 * Protects the callback call so that SIGSEGV / SIGBUS jumps back into this 1103 * method and returns false. If none of the signals are raised, returns true. 1104 * The callback is supposed to provide the method that should be protected. 1105 */ 1106 bool os::WatcherThreadCrashProtection::call(os::CrashProtectionCallback& cb) { 1107 sigset_t saved_sig_mask; 1108 1109 assert(Thread::current()->is_Watcher_thread(), "Only for WatcherThread"); 1110 assert(!WatcherThread::watcher_thread()->has_crash_protection(), 1111 "crash_protection already set?"); 1112 1113 // we cannot rely on sigsetjmp/siglongjmp to save/restore the signal mask 1114 // since on at least some systems (OS X) siglongjmp will restore the mask 1115 // for the process, not the thread 1116 pthread_sigmask(0, NULL, &saved_sig_mask); 1117 if (sigsetjmp(_jmpbuf, 0) == 0) { 1118 // make sure we can see in the signal handler that we have crash protection 1119 // installed 1120 WatcherThread::watcher_thread()->set_crash_protection(this); 1121 cb.call(); 1122 // and clear the crash protection 1123 WatcherThread::watcher_thread()->set_crash_protection(NULL); 1124 return true; 1125 } 1126 // this happens when we siglongjmp() back 1127 pthread_sigmask(SIG_SETMASK, &saved_sig_mask, NULL); 1128 WatcherThread::watcher_thread()->set_crash_protection(NULL); 1129 return false; 1130 } 1131 1132 void os::WatcherThreadCrashProtection::restore() { 1133 assert(WatcherThread::watcher_thread()->has_crash_protection(), 1134 "must have crash protection"); 1135 1136 siglongjmp(_jmpbuf, 1); 1137 } 1138 1139 void os::WatcherThreadCrashProtection::check_crash_protection(int sig, 1140 Thread* thread) { 1141 1142 if (thread != NULL && 1143 thread->is_Watcher_thread() && 1144 WatcherThread::watcher_thread()->has_crash_protection()) { 1145 1146 if (sig == SIGSEGV || sig == SIGBUS) { 1147 WatcherThread::watcher_thread()->crash_protection()->restore(); 1148 } 1149 } 1150 } 1151 1152 #define check_with_errno(check_type, cond, msg) \ 1153 do { \ 1154 int err = errno; \ 1155 check_type(cond, "%s; error='%s' (errno=%s)", msg, os::strerror(err), \ 1156 os::errno_name(err)); \ 1157 } while (false) 1158 1159 #define assert_with_errno(cond, msg) check_with_errno(assert, cond, msg) 1160 #define guarantee_with_errno(cond, msg) check_with_errno(guarantee, cond, msg) 1161 1162 // POSIX unamed semaphores are not supported on OS X. 1163 #ifndef __APPLE__ 1164 1165 PosixSemaphore::PosixSemaphore(uint value) { 1166 int ret = sem_init(&_semaphore, 0, value); 1167 1168 guarantee_with_errno(ret == 0, "Failed to initialize semaphore"); 1169 } 1170 1171 PosixSemaphore::~PosixSemaphore() { 1172 sem_destroy(&_semaphore); 1173 } 1174 1175 void PosixSemaphore::signal(uint count) { 1176 for (uint i = 0; i < count; i++) { 1177 int ret = sem_post(&_semaphore); 1178 1179 assert_with_errno(ret == 0, "sem_post failed"); 1180 } 1181 } 1182 1183 void PosixSemaphore::wait() { 1184 int ret; 1185 1186 do { 1187 ret = sem_wait(&_semaphore); 1188 } while (ret != 0 && errno == EINTR); 1189 1190 assert_with_errno(ret == 0, "sem_wait failed"); 1191 } 1192 1193 bool PosixSemaphore::trywait() { 1194 int ret; 1195 1196 do { 1197 ret = sem_trywait(&_semaphore); 1198 } while (ret != 0 && errno == EINTR); 1199 1200 assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed"); 1201 1202 return ret == 0; 1203 } 1204 1205 bool PosixSemaphore::timedwait(struct timespec ts) { 1206 while (true) { 1207 int result = sem_timedwait(&_semaphore, &ts); 1208 if (result == 0) { 1209 return true; 1210 } else if (errno == EINTR) { 1211 continue; 1212 } else if (errno == ETIMEDOUT) { 1213 return false; 1214 } else { 1215 assert_with_errno(false, "timedwait failed"); 1216 return false; 1217 } 1218 } 1219 } 1220 1221 #endif // __APPLE__